悪性星細胞腫に対する放射線治療の至適線量の検討

学位の種別: 課程博士審査委員会委員 : （主査）東京大学教授 宮川 清, 東京大学准教授 桐生 茂, 東京大学講師 榎本 敦, 東京大学講師 辛 正廣, 東京大学講師 樋渡 光輝University of Tokyo(東京大学

Features of and Mechanisms Underlying Insulitis In aly/aly Male Mice as an Animal Model of Autoimmune Pancreatitis: Activation of CD11c+, CD4+, and Th2 Cells and Predominant Destruction of β-cells

Diabetes mellitus (DM) is observed in patients with autoimmune pancreatitis (AIP). The development of DM in AIP is believed to be due to blood flow obstruction of the endocrine gland that accompanies pancreatitis, as well as injury to the islets caused by inflammation. The latter is called insulitis and the detailed mechanisms underlying its development are not yet clear. The aim of the present study was to elucidate the mechanisms involved in the development of insulitis in AIP using aly mice as an animal model of AIP: results in aly/aly male mice, as the AIP group, were compared with those inaly/+ male mice as a control group. Mice in both groups were killed between 16 and 48 weeks of age, and pancreatitis and insulitis were evaluated histologically. Inflammatory and endocrine cells were evaluated by immunofluorescence staining with anti-CD4, anti-CD8, anti-CD11b, and anti-CD11c antibodies, as well as immunohistochemical analyses using insulin and glucagon antibodies. Plasma levels and the pancreatic content of interferon (IFN)-γ (as a Th1-secreted cytokine) and interleukin (IL)-4 (as a Th2-secreted cytokine) were determined. Pancreatitis was seen in aly/aly mice from 16 weeks of age and it developed gradually thereafter. Insulitis also developed gradually and was seen in mice after 24 weeks of age in association with a decrease in the number of islets. CD11c+ cells and CD4+ T cells were seen to infiltrate into the islets. Although the number of β-cells decreased with time, the number of α-cells was maintained until mice were 48 weeks of age. IFN-γ content peaked in mice at 16 weeks of age and declined rapidly from 20 weeks. There were two peaks in IL-4 content, one at 16 weeks and the other at 32 weeks, suggesting an association between IL-4 content and advanced insulitis after 32 weeks. In conclusion, the results suggest that insulitis in AIP is induced predominantly by the infiltration of CD11c+ cells and CD4+ T cells into the islets, and progression is facilitated by the imbalance of the activation of Th2 rather than Th1. Furthermore, insulitis in AIP predominantly involves β-cells rather than α-cells

Crystal structure of (μ-hydrogen disulfato)-μ-oxido-bis[(4,4′-di-tert-butyl-2,2′-bipyridine)oxidovanadium(IV/V)] acetonitrile monosolvate

The dinuclear oxidovanadium(IV/V) complex, [V2(HS2O8)O3(C18H24N2)2]·CH3CN or [V2O2(μ-O)(μ-H(SO4)2)(4,4′-tBubpy)2]·CH3CN (4,4′-tBubpy = 4,4′-di-tert-butyl-2,2′-bipyridine), has crystallographic C2 symmetry and exhibits a distorted octahedral geometry around the vanadium center, where the two 4,4′-tBubpy ligands are nearly orthogonal to each other. The two vanadium ions are linked by an oxo anion and a unique protonated sulfate anion [H(SO4)23−]. In the crystal, intermolecular C—H...π and π–π interactions between the 4,4′-tBubpy ligands are present, leading to a three-dimensional network

4,4′-Di-tert-butyl-2,2′-bipyridinium Trifluoromethanesulfonate

4,4′-Di-tert-butyl-2,2′-bipyridinium trifluoromethanesulfonate was synthesized by stirring 4,4′-Di-tert-butyl-2,2′-bipyridine with scandium(III) trifluoromethanesulfonate in acetonitrile, followed by precipitation with diethyl ether. The structure of the new compound was characterized by FT-IR, 1H, 13C{1H} and 19F{1H} NMR spectroscopy and CHN elemental analysis. This is a safe and simple method to obtain mono-protonated bipyridinium trifluoromethanesulfonate without the direct use of trifluoromethanesulfonic acid

Photoinduced Bisphosphination of Alkynes with Phosphorus Interelement Compounds and Its Application to Double-Bond Isomerization

The addition of interelement compounds with heteroatom-heteroatom single bonds to carbon-carbon unsaturated bonds under light irradiation is believed to be an atomically efficient method to procure materials with carbon-heteroatom bonds. In this study, we achieved the photoinduced bisphosphination of alkynes using the phosphorus interelement compound, tetraphenyldiphosphine monosulfide (1), to stereoselectively obtain the corresponding (E)-vic-1,2-bisphosphinoalkenes, which are important transition-metal ligands. The bisphosphination reaction was performed by mixing 1 and various alkynes and then exposing the mixture to light irradiation. Optimization of the conditions for the bisphosphination reaction resulted in a wide substrate range and excellent trans-selectivity. Moreover, the completely regioselective introduction of pentavalent and trivalent phosphorus groups to the terminal and internal positions of the alkynes, respectively, was achieved. We also found that the novel double-bond isomerization reaction of the synthesized bisphosphinated products occurred with a catalytic amount of a base under mild conditions. Our method for the photoinduced bisphosphination of carbon-carbon unsaturated compounds may have strong implications for both organic synthesis and organometallic and catalyst chemistry