UVA-Induced Immune Suppression Through an Oxidative Pathway

Although ultraviolet B (UVB) irradiation induces local immune or systemic immune suppression, depending on the dose, the immune suppression by ultraviolet A (UVA) has not been fully investigated. In this study, we investigated the effect of UVA on the immune response in vitro and in vivo. The effect of UVA on the antigen-presenting function of epidermal cells was measured in terms of antigen-specific T cell proliferation. A murine epidermal cell suspension was exposed to UVA in vitro, pulsed with trinitrobenzenesulfonic acid, and cultured with T cells prepared from syngeneic mice previously sensitized with trinitrochlorobenzene. UVA (5–20 J per cm2) suppressed the antigenpresenting function of epidermal cells in a dose-dependent manner, accompanied with suppression of the expression of costimulatory molecules on Langerhans cells. In order to investigate the effect of an antioxidant on the immune suppression, an epidermal cell suspension was irradiated with UVA in the presence or absence of glutathione. The suppressions of antigen-presenting function and ICAM-1 expression were significantly prevented by glutathione in a dose-dependent manner. Further, the effect of UVA on the immune response at the induction phase of contact hypersensitivity was evaluated in terms of lymph node cell proliferation ex vivo. UVA irradiation suppressed the endogenous proliferation of lymph node cells in trinitrochlorobenzene-painted mice, and this suppression was significantly reversed by the application of glutathione to the skin during irradiation. These results suggest that UVA-induced immune suppression may be mediated by reactive oxygen species, at least in part

Concise, Single-Step Synthesis of Sulfur-Enriched Graphene: Immobilization of Molecular Clusters and Battery Applications

[Abstract]: The concise synthesis of sulfur-enriched Graphene for battery applications is reported. The direct treatment of graphene oxide (GO) with the commercially available Lawesson’s reagent produced sulfur-enriched-reduced GO (S-rGO). Various techniques, such as X-ray photoelectron spectroscopy (XPS), confirmed the occurrence of both sulfur functionalization and GO reduction. Also fabricated was a nanohybrid material by using S-rGO with polyoxometalate (POM) as a cathode-active material for a rechargeable battery. Transmission electron microscopy (TEM) revealed that POM clusters were individually immobilized on the S-rGO surface. This battery, based on a POM/S-rGO complex, exhibited greater cycling stability for the charge-discharge process tan a battery with nanohybrid materials positioned between the POM and nonenriched rGO. These results demonstrate that the use of sulfur-containing groups on a graphene surface can be extended to applications such as the catalysis of electrochemical reactions and electrodes in other battery systems.This work was financially supported by MEXT/JSPS KAKENHI (15K21073, 19K15539 to H.O., 16H06350, 16H02248 to H.S. and 18H04528, 17H03048, 18H04491 to H.Y.) and in part by research grants from Nippon Shokubai Co. Ltd., Kondo Zaidan, JGC-S Scholarship Foundation. We acknowledged financial support from the European Union’s Horizon2020 research and innovation program under Grant Agreements 696656 and 785219 Graphene Flagship. This work was also supported by the Spanish Ministry of Economy and Competitiveness MINECO (projects IJCI-2016-31113), by the University of Trieste, and Consorzio Interuniversitario Nazionale per la Scienza e Tecnologia dei Materiali (INSTM). MP, as the recipient of the AXA Chair, is grateful to the AXA Research Fund for financial support. This work was performed under the Maria de Maeztu Units of Excellence Program from the Spanish State Research Agency—Grant No. MDM-2017-0720. We also thank Prof. Yuta Nishina (Okayama University) for providing graphene oxide samples.MEXT/JSPS KAKENHI; 15K21073MEXT/JSPS KAKENHI; 19K15539MEXT/JSPS KAKENHI; 16H06350MEXT/JSPS KAKENHI; 16H02248MEXT/JSPS KAKENHI; 18H04528MEXT/JSPS KAKENHI; 17H03048MEXT/JSPS KAKENHI; 18H0449

キュウセイスイエンノビョウインオヨビビョウタイセイリコトニPhospholipase Aノカンヨニツイテ

京都大学0048新制・課程博士医学博士甲第1182号医博第401号新制||医||165(附属図書館)2892UT51-47-B452京都大学大学院医学研究科外科系専攻(主査)教授 本庄 一夫, 教授 木村 忠司, 教授 半田 肇学位規則第5条第1項該当Kyoto UniversityDA

Non-linear analyses of strain in flip chip packages improved by the measurement using the digital image correlation method

Numerical methods like the finite element (FE) method are often used to evaluate the reliability of electronic packages. However, the accuracy of non-linear numerical analyses should be confirmed by experimental measurements. In this study, we evaluated the strain distribution in flip chip (FC) packages with multi-layered printed circuit boards (PCBs) by combining the digital image correlation method (DICM) and the non-linear FE method, considering the viscoelasticity of resins and the elastoplasticity and creep of solder alloy. Four types of FC package consisting of two types of buildup (BU) resin and two types of underfill (UF) resin were evaluated. The distributions of strain on the cutting sections of FC packages were measured using the DICM with microphotographs obtained by a confocal laser scanning microscope (CLSM). The strain measurements showed that the UF resin with the low coefficient of thermal expansion (CTE) reduced thermal strain around a solder bump, and the BU resin with the low CTE reduced the strain concentration along the interface between a Si chip and a solder bump. We performed the non-linear FE analyses while taking into account the viscoelastic Poisson’s ratio of the UF resin and the constant instantaneous Poisson’s ratio. The result of the FE analyses with the constant instantaneous Poisson’s ratio did not correspond with the strain measurements using the DICM. The normal strain in a solder bump was less than that obtained by the measurement, and the direction of a shear strain band in a solder bump was different from that measured using the DICM. On the other hand, the FE analyses considering the viscoelastic Poisson’s ratio showed good agreement with the strain measurements using the DICM. The strain measurement using the DICM improved the accuracy of the non-linear FE analysis of microelectronic packages effectively