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IgG4 has been implicated in a diverse set of complex pathologies – e.g. autoimmune pancreatitis (AIP), idiopathic membranous nephropathy – and carries unique features including lack of activation of the classical complement pathway and a dynamic Fab-arm exchange. We recently showed that the rheumatoid factor (RF)-like activity of IgG4 is achieved through a hitherto unknown, Fc–Fc (and not Fab–Fc as is the case in classical RF; CRF) interaction; hence the name, novel RF (NRF). Here, we further explore the resemblance/difference between CRF and NRF. As heterophilic interactions of human IgM RF (CRF) are well known, we checked whether this is the case for IgG4. Human IgG4 showed variable reactivity to animal IgGs: reacting intensely with rabbit and mouse IgGs, but weakly with others. The binding to rabbit IgG was not through the Fab (as in CRF) but via the Fc piece, as was recently shown for human IgG (NRF). This binding correlates with the IgG4 concentration per se and could therefore be of diagnostic usage and incidentally explain some observed interferences in biological assays. In conclusion, here is defined a novel heterophilic antibody interaction and is established the universality of the unique Fc–Fc binding, both involving IgG4. [ABSTRACT FROM AUTHOR]

The analysis of occlusal relationship is important for the success of dental treatment. Three-dimensional (3D) computer models of upper and lower dental casts can play a significant role. In this study, we proposed and applied a new method in actual clinical assessment to measure dental casts with occlusal relationship by using a micro-focus X-ray CT system. We examined the modelling accuracy by comparing multiple 3D images taken by shifting the dental cast position. Modelling accuracy was confirmed as 0·03 mm. One occlusal treatment in clinical practice was selected as a case example. The dental casts and bite impression, taken before treatment, were scanned and the occlusal contacts and distance distribution between the upper and lower casts were visualized by a coloured map and overlaid on the computer models. Distances between the upper and lower casts of selected points were compared before and after the treatment. Initially, the subject had early contact on the anterior teeth, where distance was measured as 0·04 mm, and only one area measured less than 0·15 mm. After treatment, five areas measured less than 0·15 mm. Also, by comparing the dental cast models taken before and after occlusal adjustment of the tooth, the position and amount of adjustment were visualized. We successfully demonstrated the quantitative clinical assessment of occlusal treatment. [ABSTRACT FROM AUTHOR]

Summary On the basis of the procedure for controlling the spins of atoms using circularly polarized evanescent light proposed by Hori et al. [(1996) Abstracts of the 1st Asia-Pacific Workshop on Near-field Optics] we discuss the influence of boundary conditions on the probability of spontaneous emission and thus on the spin polarization efficiency, which was not considered in the Hori et al. study. Using the Carniglia–Mandel mode expansion of electromagnetic fields, we derive the spontaneous emission and spin polarization probabilities of atoms near a dielectric surface, and show the atom–surface distance dependence and refractive index dependence. Numerical evaluation for the 6P 1/2 –6S 1/2 transition of a Cs atom indicates an increase in the efficiency of spin polarization by 30%. [ABSTRACT FROM AUTHOR]

Summary Using density operator formalism, we discuss interdot excitation energy transfer dynamics driven by the optical near-field and phonon bath reservoir, as well as coherent excitation dynamics of a quantum dot system. As an effective interaction between quantum dots induced by the optical near-field, the projection operator method gives a renormalized dipole interaction, which is expressed as a sum of the Yukawa functions and is used as the optical near-field coupling of quantum dots. We examine one- and two-exciton dynamics of a three-quantum dot system suggesting a nanometric photonic switch, and numerically obtain a transfer time comparable with the recent experimental results for CuCl quantum dots. [ABSTRACT FROM AUTHOR]

Examines the state-selective optical near-field resonant ionization spectroscopy of atoms near a dielectric surface. Detection of optical near-fields using atomic probes; Observation of polarization nature of the optical near-field and the states of mesoscopic electronic systems; Manipulation of spin polarized electronic devices on the nanometer scale.

Objective: Adipokines may influence inflammatory and/or immune responses. This study was undertaken to examine whether adiponectin affects the production of prostaglandin E(2) (PGE(2)) by rheumatoid arthritis synovial fibroblasts (RASFs)., Methods: Synovial tissue was obtained from patients with RA who were undergoing joint replacement surgery. Fibroblast-like cells from the third or fourth passage were used as RASFs. Expression of adiponectin receptor messenger RNA (mRNA) and protein was detected. PGE(2) (converted from arachidonic acid) was measured by enzyme-linked immunosorbent assay (ELISA). Expression of mRNA and protein for cyclooxygenase 2 (COX-2) and membrane-associated PGE synthase 1 (mPGES-1), key enzymes involved in PGE(2) synthesis, was detected in RASFs. The effects of RNA interference (RNAi) targeting the adiponectin receptor genes and the receptor signal inhibitors were examined. The influence of adiponectin on NF-kappaB activation in RASFs was measured with an ELISA kit., Results: Adiponectin receptors were detected in RASFs. Adiponectin increased both COX-2 and mPGES-1 mRNA and protein expression by RASFs in a time- and concentration-dependent manner. PGE(2) production by RASFs was also increased by the addition of adiponectin, and this increase was inhibited by RNAi for the adiponectin receptor gene, or coincubation with the receptor signal inhibitors. Enhancement of NF-kappaB activation by adiponectin as well as by interleukin-1beta was observed in RASFs., Conclusion: Our findings indicate that adiponectin induces COX-2 and mPGES-1 expression, resulting in the enhancement of PGE(2) production by RASFs. Thus, adiponectin may play a role in the pathogenesis of synovitis in RA patients.

A patient with chronic eosinophilic leukemia and a unique complex chromosomal translocation 46,XY,t(3;9;5)(q25;q34;q33) who had elevated blood interleukin-5 is reported. Complete cytogenetic remission was induced by interferon-alpha after treatment failure with corticosteroids and cytotoxic drugs. Severe cardiopulmonary symptoms due to hypereosinophilia and thromboembolic complication improved dramatically in the first 6 months of interferon therapy. Since it is known that the gene encoding for interleukin-5 resides on the long arm of chromosome 5, it may be possible that the chromosomal translocation in our patient resulted in overproduction of this cytokine, and our findings may be helpful for understanding the pathogenesis of this disorder.