Bacterial pneumonia can increase serum concentration of clozapine

Concentrations of serum clozapine, C-reactive protein (CRP) and alpha1 acid glycoprotein were greatly increased during a bacterial pneumonia in a 53-year-old woman. As the pneumonia subsided, and CRP and alpha1 acid glycoprotein normalised, serum clozapine concentration also decreased to the previous level. An increased serum clozapine and a lowered N-desmethylclozapine to clozapine ratio during the infection suggest a decreased cytochrome P(450) (CYP)1A2 activity. Cytokine-mediated CYP1A2 suppression is discussed.     

Comparison of polyclonal and monoclonal antibodies to Actinomyces and Arachnia species

Polyclonal (PoAbs) and monoclonal (MoAbs) antibodies were produced to Actinomyces israelii serotypes 1 and 2, to Actinomyces naeslundii, and to Arachnia propionica, and their specificities were studied by an enzyme immunoassay (EIA). All PoAbs except those to A. propionica reacted also with at least one other Actinomyces species. Only the MoAb to A. naeslundii proved to be more specific than the corresponding PoAbs. This MoAb did not crossreact with other Actinomyces or Arachnia species, nor with any other anaerobic or aerobic bacteria studied by inhibition EIA. Immunoblotting studies indicated that the antibody specific to A. naeslundii is directed against a large molecular weight antigen (greater than 150 kd), probably polysaccharide in nature. The produced PoAbs and MoAbs can be used for further analyses of the antigenic determinants of different Actinomyces and Arachnia species.     

Association of rheumatoid arthritis disease activity and antibodies to periodontal bacteria with serum lipoprotein profile in drug naive patients

Abstract

Objective: We investigated lipid concentrations, particle sizes and antibodies binding to periodontal bacteria Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis and to malondialdehyde-acetaldehyde (MAA) modified low-density lipoprotein in immunoglobulin (Ig) class A, G and M among patients with newly diagnosed rheumatoid arthritis (RA) in a population-based cohort.

Methods: Concentrations and sizes of lipoprotein particles analysed by proton nuclear magnetic resonance spectroscopy and antibody levels to MAA modified low-density lipoprotein were studied at baseline and after one-year of follow-up. Serum Ig A and G class antibodies to periodontal bacteria were determined at baseline.

Results: Sixty-three patients were divided into tertiles according to disease activity by disease activity score with 28 joint count and erythrocyte sedimentation rate (ESR) (<3.9, 3.9–4.7, >4.7). Small low-density lipoprotein concentration was lowest in the tertile with the highest disease activity. In high-density lipoprotein, the concentrations of total, medium and small particles decreased with disease activity. The particle size in low-density lipoprotein associated with disease activity and the presence of antibodies to P. gingivalis. Ig G and M antibodies to MAA modified low-density lipoprotein correlated with disease activity. Inflammation associated changes faded by one year.

Conclusions: Drug naive RA patients had proatherogenic changes in lipid profiles, but they were reversible, when inflammation diminished.

• Key messages

• Patients with drug naive rheumatoid arthritis showed proatherogenic lipid profiles.

• Reversible changes in lipid profiles can be achieved as response to inflammation suppression.

• Active therapy aimed at remission is essential in all patients with rheumatoid arthritis.

     

Elongation and plasmonic activity of embedded metal nanoparticles following heavy ion irradiation

Shape modification of embedded nanoparticles by swift heavy ion (SHI) irradiation is an effective way to produce nanostructures with controlled size, shape, and orientation. In this study, randomly oriented gold nanorods embedded in SiO₂ are shown to re-orient along the ion beam direction. The degree of orientation depends on the irradiation conditions and the nanorod''s initial size. SHI irradiation was also applied to modify spherical metallic nanoparticles embedded in Al₂O₃. The results showed that they elongate due to the irradiation comparably to those embedded in SiO₂. Metallic nanostructures embedded in dielectric matrices can exhibit localized surface plasmon (LSP) modes. The elongated nanoparticles investigated by means of dark-field spectroscopy showed two discrete peaks which correspond to longitudinal and transverse modes.

Shape modification of embedded nanoparticles by swift heavy ion (SHI) irradiation is an effective way to produce nanostructures with controlled size, shape, and orientation.     

Characterization of a hamster brain cell line persistently infected with measles virus

Summary A persistent infection of measles virus in hamster brain cell cultures was established. Hamster brain cells were transformed with a human papovavirus strain BK and infected with a wild-type measles virus in order to get the cell line persistently infected with measles virus. About 75 per cent of these M-HB/MVB-cells were measles virus-infected. The cells released only small amount of infectious virus and produced low levels of interferon-like activity into the growth medium. During the first 50 passages no large syncytia typical of a lytic measles virus infection were seen. The products of measles virus infection in the cells and in cell culture fluids were followed at two temperatures. Another cell line persistently infected with measles virus (Lu-carrier-cells, 28) was investigated in parallel. In both cell lines measles antigens were cytoplasmic, but during the observation period large amounts of measles nucleocapsid accumulated in the nuclei of the M-HB/MVB-cells. The virus-specific protein synthesis in M-HB/MVB-cells was weak and the intracellular amount of immunoreactive measles nucleocapsid was only 50 per cent (600 ng/10⁵ infected cells) of that (1200 ng/10⁵ cells) found in Lu-carrier-cells. Also the release of nucleocapsid was minimal in hamster brain cells. The decreased temperature had no clear-cut effect on virus-specific protein synthesis or on the release of the virus-specific products.With 3 Figures