Detection of influenza A(H1N1)v virus by real-time RT-PCR.

Influenza A(H1N1)v virus was first identified in April 2009. A novel real-time RT-PCR for influenza A(H1N1)v virus was set up ad hoc and validated following industry-standard criteria. The lower limit of detection of the assay was 384 copies of viral RNA per ml of viral transport medium (95% confidence interval: 273-876 RNA copies/ml). Specificity was 100% as assessed on a panel of reference samples including seasonal human influenza A virus H1N1 and H3N2, highly pathogenic avian influenza A virus H5N1 and porcine influenza A virus H1N1, H1N2 and H3N2 samples. The real-time RT-PCR assay for the influenza A matrix gene recommended in 2007 by the World Health Organization was modified to work under the same reaction conditions as the influenza A(H1N1)v virus-specific test. Both assays were equally sensitive. Clinical applicability of both assays was demonstrated by screening of almost 2,000 suspected influenza (H1N1)v specimens, which included samples from the first cases of pandemic H1N1 influenza imported to Germany. Measuring influenza A(H1N1)v virus concentrations in 144 laboratory-confirmed samples yielded a median of 4.6 log RNA copies/ml. The new methodology proved its principle and might assist public health laboratories in the upcoming influenza pandemic.

[Thrombangiitis obliterans: diagnosis and therapy in light of new immunological findings]. / Thrombangiitis obliterans: Diagnose und Therapie im Licht neuer immunologischer Befunde.

Thrombangiitis obliterans, a segmental, multilocal, inflammatory disease of the small and medium-sized arteries and veins, is characterized by the relatively juvenile onset of the disease, the peripheral localization of the arterial occlusions and by phlebitis saltans. Other diagnostic criteria are the absence of risk factors typical of atherosclerosis (except smoking), strictly localized occlusion on angiography, phasic clinical course, and exclusion of either collagen disease or essential thrombocytosis. A possible immunopathogenesis for the disease is increasingly favored. In our own study of 33 patients the complement factor C4 was increased in 54.6%, the antielastin antibodies were found at a titre of 1:8 in 57.1% and the immuncomplexes in 23.3%. In only 1 case was the histocompatibility antigen HLA B 12 absent. In view of these immunologic findings and also the fact that phlebitis saltans as a symptom of the disease can be suppressed by salicylates and corticosteroids, but not by anticoagulants, the following therapy is proposed: high doses of acetylsalicylic acid during the acute stage of the illness, or, if this regimen fails, a trial with corticosteroids or immunosuppressive agents.

Transmission of incoherent light between ronchi grids.

The use of Ronchi grids for the detection or measurement of small angular changes is well known. In some applications, such as instruments for the measurement of strain or displacement, the question of linearity of calibration over an extended angular range is important. In this paper we treat the question of such linearity on the basis of physical optics. We conclude that although arbitrary combinations of wavelength or wavelength range, grating space, focal length, and beam width generally yield a nonlinear calibration, special combinations of these parameters result in a highly linear curve over an extended range.