ObjectiveNoninvasive imaging by positron emission tomography (PET) of macrophages in inflamed joints of patients with rheumatoid arthritis (RA) may allow early detection of disease activity. We undertook this study to investigate whether rheumatoid synovitis can be visualized by PET using the tracer 11C‐(R)‐PK11195, which binds to peripheral benzodiazepine receptors (PBRs) on macrophages.MethodsKnee joints of 11 RA patients with active arthritis of at least 1 knee joint were imaged with 11C‐(R)‐PK11195 PET. Tissue uptake of 11C‐(R)‐PK11195 was quantified. PET was followed by arthroscopy of the most inflamed knee joint of each RA patient. Synovial tissue samples were subjected to immunohistochemical staining.Results11C‐(R)‐PK11195 uptake on the PET scans was significantly higher in severely inflamed joints than in joints with moderate or mild signs of inflammation. In addition, tracer uptake in contralateral uninflamed knee joints of RA patients was significantly higher than in uninflamed joints of control patients without inflammatory joint disease, suggesting the presence of subclinical disease activity. PET tracer uptake in joints correlated significantly with PBR staining in the sublining of synovial tissue. PBR staining correlated significantly with CD68 staining of macrophages.Conclusion11C‐(R)‐PK11195 PET imaging allows noninvasive in vivo imaging of macrophages in rheumatoid synovitis and possibly even in subclinical synovitis. Noninvasive visualization of macrophages may be useful both for detecting early synovitis and for monitoring synovitis activity during treatment.

ABSTRACT:The radical graft polymerization of vinyl monomers from inorganic ultrafine particles, such as silica, titanium oxide, and ferrite, by use of azo groups introduced onto their surface was investigated. The introduction of azo groups onto the ultrafine particles was achieved by the reaction of glycidyl groups, which were introduced by the reaction of hydroxyl groups on the surface with 3-glycidoxypropyltrimethoxysilane, with 4,4'-azobis(4-cyanopentanoic acid). The amounts of azo groups introduced onto silica, titanium oxide, and ferrite were determined to be 0.07, 0.05, and 0.03 mmol g ·· 1 , respectively. The polymerization of vinyl monomers, such as methyl methacrylate (MMA), styrene, and N-vinylcarbazole (NVC), was found to be initiated by radicals formed by the decomposition of the azo groups. During the polymerization, the polymer was effectively grafted onto these surfaces through propagation from the surfaces; the percentage of grafting of polyMMA onto silica, titanium oxide, and ferrite reached to 45

SUVmax, a metabolic semiquantitative parameter, shows a significant correlation with the molecular subtype of breast cancer, and is useful for predicting the luminal A or HER2-positive subtype.

A stress-operated memory device consisting of an ellipsoidal magnetic particle array and an electrostrictive grid is proposed. In the device, the magnetic state of the particle can be controlled only by the magnetostriction effect. Each particle is located at the intersection of the grid and has an in-plane uniaxial anisotropy. A pair of electric contacts is connected to the end of each wire. In the writing process, the driving voltages are simultaneously applied to two pairs of the selected contacts. This allows to apply a local electric field whose direction and amplitude can be regulated by varying the voltage intensity and polarity. The exerting stress on the magnetic particle results in the linear magnetostriction and hence an additional anisotropy energy in the particle. The in-plane total energy minimum, corresponding to the magnetization direction, follows the local electric field. Consequently the magnetization of the single magnetic particle located at the intersection can therefore be selectively switched.