Melanins are implicated in the pathogenesis of several important human diseases. This study confirmed the presence of melanin particles in Candida albicans in vitro and during infection. Dark particles were isolated from the digestion of C. albicans cultures and from infected tissue, as established by electron microscopy and immunofluorescence techniques.

In this paper we describe evaluation and characterization of a novel assay that combines immunomagnetic separation and a fluorescently stained bacteriophage for detection of Escherichia coli O157:H7 in broth. When it was combined with flow cytometry, the fluorescent-bacteriophage assay (FBA) was capable of detecting 10(4) cells/ml. A modified direct epifluorescent-filter technique (DEFT) was em...

The detection of immunoglobulin M (IgM) antibodies to cytomegalovirus-induced late antigens by an indirect immunofluorescence assay was improved by the use of monoclonal antibodies to human IgM. Nonspecific background fluorescence was absent, facilitating the reading of the slides and the detection of a specific fluorescence reaction in sera with low levels of specific IgM. Moreover, the indire...

In this study, we collected serum from 82 randomly selected patients from a rural area in Jaguapitã county, Paraná State. All sera were subjected to indirect immunofluorescence assay (IFA) to detect IgG antibodies against T. gondii. Serum titers >/=+ 16 were considered positive. Of the 82 evaluated sera, 68 (82.9%) were positive to toxoplasmosis and 14 (17.1%) were non-reactive. The most common...

It is technically impractical for many clinical laboratories to use the direct immunofluorescence assay for identifying and serogrouping clinical isolates of Legionella. We compared the results obtained with the direct immunofluorescence assay with the results of a simple and less-demanding slide agglutination test for identifying 15 serogroups representing seven Legionella species. The slide a...

An experimental study was conducted to evaluate the potential presence of porcine circovirus type 2 (PCV2) in the semen of infected boars. Four mature boars were inoculated intranasally with PCV2 isolate LHVA-V53 propagated on PK15 cells. Two boars inoculated with the supernatant of noninfected PK15 cells were kept as controls. Serum samples were collected from all boars at 4, 7, 11, 13, 18, 21...

Between 2007 and 2010, the Netherlands experienced one of the largest outbreaks of Q fever. Since asymptomatic Coxiella burnetii infection has been associated with maternal and obstetric complications, evidence about the effectiveness of routine screening during pregnancy in outbreak areas is needed. We performed a clustered randomised controlled trial during the Dutch outbreak, in which 55 mid...

Antinuclear antibodies (ANA) represent the main diagnostic markers for systemic autoimmune disease (AD), although their presence can be detected in blood donors. The aim of this study was to study ANA prevalence in healthy subjects of different racial groups, exposed to the same environmental factors, in order to understand the relevance of genetics or environment in determining autoimmunity. W...

Pitfalls in the method for demonstrating antinuclear antibodies (ANA) by the indirect immunofluorescence technique are described and the use of international standard preparations outlined. Determination of the optimal border dilution dividing positive from negative results is discussed. Each laboratory is a unique setting; it must define its own method, which should rarely be changed. One shou...