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131.
Suhyeon Kim Si-Yeon Lee Seoyoon Bae Jin-Kwan Lee Kyungrim Hwang Heounjeong Go Chang-Woo Lee 《Experimental & molecular medicine》2020,52(9):1537
Psoriasis is one of the most common immune-mediated chronic inflammatory skin diseases. However, little is known about the molecular mechanism underlying the immunological circuits that maintain innate and adaptive immune responses in established psoriasis. In this study, we found that the Pellino1 (Peli1) ubiquitin E3 ligase is activated by innate pattern-recognition receptors (PRRs), such as Toll-like receptors (TLRs), and is highly upregulated in human psoriatic skin lesions and murine psoriasis-like models. Increased Peli1 expression is strongly correlated with the immunopathogenesis of psoriasis by activating hyperproliferation of keratinocytes in the S and G2/M phases of the cell cycle and promoting chronic skin inflammation. Furthermore, Peli1-induced psoriasis-like lesions showed significant changes in the expression levels of several T helper 17 (Th17)-related cytokines, such as IL-17a, IL-21, IL-22, IL-23, and IL-24, indicating that overexpression of Peli1 resulted in the sequential engagement of the Th17 cell response. However, the overexpression of Peli1 in T cells was insufficient to trigger psoriasis, while T cells were indispensable for disease manifestation. In summary, our findings demonstrate that Peli1 is a critical cell cycle activator of innate immunity, which subsequently links Th17 cell immune responses to the psoriatic microenvironment.Subject terms: Chronic inflammation, Immunoproliferative disorders 相似文献
132.
Tjoe-hian Go 《Communications in Mathematical Physics》1975,41(2):157-173
Contrary to the eleven-parameter group consisting of Poincaré-transformations and dilatations, the group of so-called special conformal transformations can act on the Minkowski space only as a local conformal Lie transformation group. We show that the universal covering space of the compactified Minkowski space , together with an appropriate metric \(\tilde g\) on it, form a suitable Lorentz manifold that admits universal covering group of the “conformal group” of as a transitive Lie transformation group. This group respects the causality notion on usually defined on a Lorentz manifold. However, possesses only seven isometries in contrast to the well-known ten isometries on the Minkowski space , which correspond to conservation of energy-momentum and angular-momentum. 相似文献
133.
All known assignments of electronic transitions in the [Fe(CN)5NO]2? ion are inconsistent with the observed characteristics of absorption bands and with the most recent data on photoactivity. Results of more advanced calculations are presented, with Scaled INDO SCF calculations repeated for all excited states separately. In contrast to the older treatments it proves possible to explain why band I is inactive, why irradiation within the band II results in a pure exchange of NO+ and H2O and why irradiation within the frequency range of band IV results in a redox reaction, followed by exchange of NO and H2O. 相似文献
134.
135.
Mutagenicity of steviol and its oxidative derivatives in Salmonella typhimurium TM677 总被引:4,自引:0,他引:4
Stevioside is natural non-caloric sweetner isolated from Stevia rebaudiana BERTONI, which has been used as a non-caloric sugar substitute in Japan. Pezzuto et al. demonstrated that steviol shows a dose-dependent positive response in forward mutation assay using Salmonella typhimurium TM677 in the presence of metabolic activation system (Aroclor induced rat liver S9 fraction). Our studies were carried out to identify the genuine mutagenic active substance from among the eight steviol derivatives. Steviol indicate almost similar levels of mutagenicity under the presence of S9 mixture, as reported by Pezzuto et al. 15-Oxo-steviol was found to be mutagenic at the one tenth the level of steviol itself under the presence of S9 mixture. Interestingly, specific mutagenicity of the lactone derivative under the presence of S9 mixture was ten times lower than that of the lactone derivative without the addition of S9 mixture. 相似文献
136.
Random copolymers of cis- and trans-1,4-cyclohexylenedimethylene terephthalate were permitted to undergo ester-interchange reorganization at temperatures just below the melting point. As predicted from the principles of crystallization-induced reactions of semicrystalline copolymers proposed in the first two papers of this series, the copolymers were observed to undergo changes in physical properties which are associated with the conversion of a random to a block copolymer. The driving force for this antiequilibrium ordering process is believed to be the irreversible expansion of the crystalline regions following replacement of cis by trans glycol units. Solubility, crystallinity, and crystallization properties were monitored to determine the effects of copolymer composition, temperature, catalyst, and molecular weight on the reorganization rate. This type of process is also believed to be responsible for the direct preparation of block copolymers by a solid-state polycondensation reaction used in this study. 相似文献
137.
138.
Preparation of ureido group bearing polymers and their upper critical solution temperature in water
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Ami Fujihara Kohei Itsuki Naohiko Shimada Atsushi Maruyama Naoya Sagawa Toshiyuki Shikata Shin‐Ichi Yusa 《Journal of polymer science. Part A, Polymer chemistry》2016,54(18):2845-2854
Poly(2‐ureidoethylmethacrylate) (PUEMn) was synthesized via reversible addition‐fragmentation chain transfer (RAFT) radical polymerization and following polymer reaction. We prepared two PUEMn samples with different degrees of polymerization (n = 100 and 49). The polymers exhibited upper critical solution temperature (UCST) in phosphate‐buffered saline (PBS) solution. The phase separation temperature (Tp) in PBS can be controlled ranging from 17 to 55 °C by changing molecular weight of the polymer, polymer concentration, and adding NaCl concentration. The polymers in PBS formed coacervate drops by liquid–liquid phase separations below Tp. Results of the dielectric relaxation measurement, the hydration number per monomeric unit was 5 above Tp. Based on a fluorescence study, the polymer formed slightly hydrophobic environments below Tp. The liquid–liquid phase separation was occurred presumably because of weak hydrophobic interactions and intermolecularly hydrogen bonding interactions between the pendant ureido groups. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 2845–2854 相似文献
139.
Jae-Wook Kang Deug-Sang Lee Hyung-Dol Park Ji Whan Kim Won-Ik Jeong Young-Seo Park Se-Hyung Lee Kyungmoon Go Jong-Soon Lee Jang-Joo Kim 《Organic Electronics》2008,9(4):452-460
A host material containing tetraphenylsilane moiety, 9-(4-triphenylsilanyl-(1,1′,4,1′′)-terphenyl-4′′-yl)-9H-carbazole (TSTC), was synthesized for green phosphorescent organic light emitting diodes. The tetraphenylsilane moiety was introduced to provide high triplet energy level, thermal and chemical stability, and glassy properties leading to high efficiency and operational stability of the devices. Ir(ppy)3 based OLEDs using the TSTC host and DTBT (2,4-diphenyl-6-(4′-triphenylsilanyl-biphenyl-4-yl)-1,3,5-triazine) hole blocking layer (HBL) resulted in the maximum external quantum efficiency of 19.8% and the power efficiency of 59.4 lm/W. High operational stability with a half lifetime of 160,000 h at an initial luminance of 100 cd/m2 was achieved from an electrophosphorescent device using TSTC host and BAlq HBL. 相似文献
140.
Hin‐Koon Woo Eden P. Go Linh Hoang Sunia A. Trauger Benjamin Bowen Gary Siuzdak Trent R. Northen 《Rapid communications in mass spectrometry : RCM》2009,23(12):1849-1855
Mass spectrometry has become an indispensable tool for the global study of metabolites (metabolomics), primarily using electrospray ionization mass spectrometry (ESI‐MS). However, many important classes of molecules such as neutral lipids do not ionize well by ESI and go undetected. Chemical derivatization of metabolites can enhance ionization for increased sensitivity and metabolomic coverage. Here we describe the use of tris(2,4,6,‐trimethoxyphenyl)phosphonium acetic acid (TMPP‐AA) to improve liquid chromatography (LC)/ESI‐MS detection of hydroxylated metabolites (i.e. lipids) from serum extracts. Cholesterol which is not normally detected from serum using ESI is observed with attomole sensitivity. This approach was applied to identify four endogenous lipids (hexadecanoyl‐sn‐glycerol, dihydrotachysterol, octadecanol, and alpha‐tocopherol) from human serum. Overall, this approach extends the types of metabolites which can be detected using standard ESI‐MS instrumentation and demonstrates the potential for targeted metabolomics analysis. Published in 2009 by John Wiley & Sons, Ltd. 相似文献