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Abstract Background [F-18]fluorodeoxyglucose positron emission tomography/computed tomography is routinely used for assessing Takayasu arteritis patients. However, extra-vessel [F-18]fluorodeoxyglucose uptake has not been evaluated in detail in these patients. We aimed to describe the extent and distribution of extra-vascular [F-18]fluorodeoxyglucose uptake on positron emission tomography/computed tomography in Takayasu arteritis patients. Seventy-three [F-18]fluorodeoxyglucose positron emission tomography/computed tomography scans from 64 consecutive Takayasu arteritis patients (59 women, mean age, 35.4 years; range, 13 to 71 years) and 40 scans from age-matched controls (36 women, mean age, 37.8 years; range, 13 to 70 years) were examined. We graded [F-18]fluorodeoxyglucose uptake in large vessels using a 4-point scale and evaluated extra-vessel findings. Factors correlated with disease activity were examined. We evaluated the relationship between disease activity according to the National Institutes of Health score with extra-vessel findings, as well as other inflammatory markers (e.g., white blood cell count and C-reactive protein level). Results Extra-vessel involvement was present in 50 of 73 (68.4%) scans, specifically at the following sites: lymph nodes, 1.4%; thyroid glands, 17.8%; thymus, 11.0%; spleen, 1.4%; vertebrae, 45.2%; and pelvic bones, 9.6%. Takayasu arteritis patients had higher [F-18]fluorodeoxyglucose uptake in the spine (P = 0.03) and thyroid glands (P = 0.003) than did controls; uptake in other regions was comparable between groups. Compared with inactive patients, those with active Takayasu arteritis had a higher number of [F-18]fluorodeoxyglucose uptake sites in the vasculature (P = 0.001). Finally, patients with a National Institutes of Health score of ≥ 1 had significantly higher extra-vascular involvement (P = 0.008). Conclusions Extra-vessel [F-18]fluorodeoxyglucose uptake may be present in the context of Takayasu arteritis-related inflammatory processes. Information on extra-vascular [F-18]fluorodeoxyglucose uptake may be useful for detecting and evaluating inflammatory processes when interpreting positron emission tomography/computed tomography scans obtained from Takayasu arteritis patients.

Grignard reagents (R²MgBr; R² = Me, p-tolyl) regioselectively attacked the α-carbon of the bridgehead double bond of methyl- and benzylazafulleroids (only R² = Me) in contrast to the β-carbon attack for tosylazafulleroid. A DFT calculation proved the α-addition through the favorable interaction of Mg and the bridged nitrogen atom. The α-adduct further underwent methylation on basic treatment with methyl iodide. [ABSTRACT FROM AUTHOR]

Antioxidant activity of hydroxylated fullerenes, so-called fullerenols, against lipid peroxyl radical was evaluated by β-carotene bleaching assay. All samples showedmoderate to high antioxidant activity (%AOA), especially for C60(OH)12 (70.1) and C60(OH)44 (66.0) as compared with 8, 24, 26, and 36 hydroxylated ones (31.7-62.8).The detection of the possible products was conducted in the model reaction of both fullerenols and C60 with methyl linoleate by MALDI-TOF-MS. These results suggested that the two possible mechanisms, such as C-addition to double bonds and H-abstraction from-OH groups, are involved in the present radical scavenging reaction. [ABSTRACT FROM AUTHOR]

A kinetic study has been made of the BF 3-mediated ring opening of two rigid conformers (α and β) of m- and p-dimethyl-substituted homobenzoquinone epoxides spiro-linked with a twist-boat dibenzocycloheptene ring as compared with the conformationally mobile epoxides bearing diphenyl groups. The rates of the regioselective ring opening were dependent on the topological alignment of the dibenzocycloheptene ring as well as the substitution pattern of the quinone dimethyl groups, indicating π-aryl participated orbital interaction with the vacant Walsh orbital of the oxirane ring. [ABSTRACT FROM AUTHOR]

The kinetics of the thermal rearrangement of a series of novel cyclopropyl-substituted 5,6 open fulleroids to the 6,6 closed methanofullerenes have been investigated in comparison with the aryl-substituted homologues. The cyclopropyl group markedly accelerated the rates due to the stereoelectronically favorable -conjugative effects in the radical-like 1,5 shift of the transient 5,6 closed isomers, overriding the geometrically constrained aryl group. [ABSTRACT FROM AUTHOR]

Novel single electron transfer (SET) reaction of dienamine with C60 is presented. The generated dienamine radical cation underwent a 1,6-hydrogen shift followed by a radical-ion coupling with a C60 radical anion to give pyrrolidinofullerene. The radical process was proven by spin-trapping experiments as well as DFT calculations. [ABSTRACT FROM AUTHOR]

The acid-induced reaction of bis(p-chlorophenyl)homobenzoquinone epoxide gave the dual ipso/ortho intramolecular SE2-Ar products associated with π-aryl participated oxirane ring opening, whereas bis(p-tolyl)- and diphenyl-substituted homologues provided only the ortho products. [ABSTRACT FROM AUTHOR]

We studied the kinetics of the Diels–Alder reaction of Li+-encapsulated [60]fullerene with 1,3-cyclohexadiene and characterized the obtained product, [Li+@C60(C6H8)](PF6–). Compared with empty C60, Li+@C60 reacted 2400-fold faster at 303 K, a rate enhancement that corresponds to lowering the activation energy by 24.2 kJ mol–1. The enhanced Diels–Alder reaction rate was well explained by DFT calculation at the M06-2X/6-31G(d) level of theory considering the reactant complex with dispersion corrections. The calculated activation energies for empty C60 and Li+@C60 (65.2 and 43.6 kJ mol–1, respectively) agreed fairly well with the experimentally obtained values (67.4 and 44.0 kJ mol–1, respectively). According to the calculation, the lowering of the transition state energy by Li+ encapsulation was associated with stabilization of the reactant complex (by 14.1 kJ mol–1) and the [4 + 2] product (by 5.9 kJ mol–1) through favorable frontier molecular orbital interactions. The encapsulated Li+ ion catalyzed the Diels–Alder reaction by lowering the LUMO of Li+@C60. This is the first detailed report on the kinetics of a Diels–Alder reaction catalyzed by an encapsulated Lewis acid catalyst rather than one coordinated to a heteroatom in the dienophile. [ABSTRACT FROM AUTHOR]