scholarly journals Molluscum contagiosum: serology and electron microscopy findings in twenty one patients

Author(s):  
M. E. F. Fonseca ◽  
R. D. Machado ◽  
M. I. M. Liberto ◽  
G. Marcolino

Twenty one cases of molluscum contagiosum virus disease were collected for electron microscopical and serological tests. Molluscum virus was detected in the crust, inside the vacuoles formed in the keratinocytes cells. The patients developed specific antibodies to the virus detected by complement fixation test.

1976 ◽  
Vol 76 (2) ◽  
pp. 287-298 ◽  
Author(s):  
G. S. Allan ◽  
R. J. Chappel ◽  
P. Williamson ◽  
D. J. McNaught

SUMMARYBrucella-specific antibodies of different immunoglobulin classes were quantitatively evaluated with respect to their efficiency in serological tests for bovine brucellosis.IgM reacted more efficiently than IgG1and IgG2in both the Rose Bengal plate test and serum agglutination test. The complement fixation test was found to be slightly more sensitive to IgM than to IgG1and did not react to IgG2.IgM was, however, partly inactivated when heated at 60°C. in the presence of serum.


2004 ◽  
Vol 87 (4) ◽  
pp. 965-971 ◽  
Author(s):  
Donatella Nannini ◽  
Manuela Tittarelli ◽  
Lucilla Ricci ◽  
Annamaria Conte ◽  
Bernardo Di Emidio ◽  
...  

Abstract A model interlaboratory testing scheme was developed by the Italian National Reference Laboratory for Brucellosis. This scheme was planned for both qualitative (Rose Bengal Plate Test; RBPT) and quantitative (Complement Fixation Test; CFT) serological tests and involved a total of 42 laboratories. In the preparation of this scheme, reference was made to general protocols and guidelines and to methods reported in the literature, which were applicable to analytical chemistry laboratories. Six field sera from naturally infected animals, one positive serum at a titer below the European Union (EU) positivity threshold, and 5 sera positive at titers between 20 and 851 International Units of Complement Fixation Test (IUCFT)/mL plus one negative serum were used to produce a panel of test sera. To evaluate laboratory performances in the quantitative test for each tested sample examined, z-scores based on robust summary statistics (the median and normalized interquartile range) were used. To evaluate overall laboratory performance, 2 types of combined z-scores were used: Rescaled Sum of Scores and Sum of Squared Scores. In the case of the qualitative test (RBPT), results were analyzed by a Bayesian approach. A Beta distribution, based on the result of each laboratory, was calculated and used to estimate the probability of each laboratory giving a correct result and its uncertainty.


1960 ◽  
Vol 6 (4) ◽  
pp. 453-462 ◽  
Author(s):  
N. A. Labzoffsky ◽  
A. E. Kelen

Methods of preparation of "whole" and type-specific antigens from leptospiral cultures for use in the complement fixation test are outlined. Leptospiral cultures grown in Korthof's medium were treated with pyridine and after appearance of a copious precipitate were centrifuged. The supernatants were dialyzed and after concentration by pervaporation were used as "whole" antigens. Type-specific antigens were prepared from acetone precipitates of filtrates of "whole" antigens. Considerable cross reaction was observed with "whole" antigens prepared from L. pomona, L. canicola, and L. icterohaemorrhagiae and their respective rabbit hyperimmune sera, although titers with homologous sera were invariably higher. These cross reactions, however, were not as pronounced with sera from cattle naturally infected with L. pomona, where approximately 43% of the sera reacted with homologous antigen only. No reactions were observed between the type-specific antigen and any of the heterologous sera employed. It has also been shown that with experimental sera type-specific antibodies appeared earlier and persisted longer than group-specific antibodies. In view of the above observations the use of polyvalent antigen for routine screening of leptospiral antisera is advocated. Type-specific antigens are recommended for use in more precise diagnosis.


1960 ◽  
Vol 15 (6) ◽  
pp. 375-378
Author(s):  
Arno Geissler ◽  
Wolfgang Müller-Ruchholtz ◽  
Else Knake

The immunization of highly inbred Wistar rats with a Benzpyrene-Sarcoma produced in this strain did not stimulate the formation of circulating tumor-specific antibodies. In these studies the complement fixation test, the colloid-complement fixation test, the ring precipitin test, the agar-gel-diffusion technic of Ouchterlony and tissue cultures for the study of cytotoxic antibodies were used.


2021 ◽  
Vol 15 (1) ◽  
pp. 71-78
Author(s):  
Ch. Georgiou

The purpose of the research is developing a method for obtaining erythrocyte antigens containing and not containing Trypanosoma equiperdum and T. evansi DNA, which can later be used in serological reactions to differentiate these types of Trypanosoma.Materials and methods. The studies were conducted in the Protozoology Laboratory and the Vyshnevolotsk Branch of the Federal State Budget Scientific Institution “Federal Scientific Centre VIEV RAS”, as well as livestock farms of the Russian Federation and other countries using clinical, microscopic, hematological, parasitological, biomolecular and serological methods.Results and discussion. Studies carried out for the first time have shown that it is possible to use erythrocyte antigens containing the T. equiperdum and T. evansi DNA obtained after 3-fold administration to mice and rabbits of a mixture of trypanosomal antigen with addition of 1.0 ml of an adjuvant (aluminum hydroxide), and bleeding of animals at 25 to 30 days. The formed precipitate was used as an antigen for serological tests. Experiments have shown that blood for preparation of positive serum can be taken when antibodies are in titers of 1:20 in the Prolonged Complement Fixation Test, and at least 1:400 in the Indirect Hemagglutination Test and ELISA, and for negative serum when horse blood serum reacts negatively with antigens of T. equiperdum and T. evansi in the Prolonged Complement Fixation Test, Indirect Hemagglutination Test and ELISA. The test systems of the Prolonged Complement Fixation Test, Indirect Hemagglutination Test and ELISA prepared by us with antigens containing and not containing T. equiperdum and T. evansi DNA resulted in creating a universal test system (Indirect Hemagglutination Test) for differentiating T. equiperdum from T. evansi.


1993 ◽  
Vol 4 (1) ◽  
pp. 43-46 ◽  
Author(s):  
Laila Sekla ◽  
Walter Stackiw ◽  
Gudrun Eibisch ◽  
Donna Kolton

Objectives: To report an epidemic ofMycoplasma pneumoniaein Manitoba and to discuss the limitations of the serodiagnostic tests used.Design: A retrospective analysis of the results of a province-wide serological testing for respiratory infections caused byM pneumoniae,using a complement fixation test and an indirect immunofluorescent antibody test for the detection of immunoglobulin (Ig) M antibodies.Material: From April 1, 1987, to March 31, 1991, 12,804 sera were tested and a serological diagnosis of recentM pneumoniaeinfections were established in 509 (3.97%). From April 1 to September 30, 1991, an additional 2088 persons were tested; the 158 (7.5%) recent cases ofM pneumoniaewere subjected to analysis.Results: Compared with the previous three years, an increase in the number of recent cases ofM pneumoniaewas first noticed in July 1990 which persisted until September 1991. Of 856 single sera tested, 59 (6.8%) were recentM pneumoniaeinfections and 56 (96.1%) of these were positive for IgM antibodies. Of the 616 persons who submitted paired sera, 99 (16%) were recent infections, but only 46 (46.4%) had IgM antibodies. Primary infections (ie, positive for IgM antibodies) were detected in 102 (64.5%) and reinfections (ie, positive complement fixation test only) in the remaining 56 persons with recentM pneumoniaeinfections. Primary infections were detected more frequently in the ‘under 16’ than in the ‘over 16’ year age group (75% versus 55.8% of the recent cases ofM pneumoniaein each age group). Reinfections were more common in the older age group. Of the 158 recent cases ofM pneumoniae,30.3% had a pneumonia; of these, 21 (55.2%) were under the age of 16 years.Discussion:M pneumoniaeis an important cause of morbidity. Serological tests are used for the diagnosis despite their limitations. The detection of IgM antibodies in acute serum establishes a diagnosis of primaryM pneumoniae;however, their absence does not excludeM pneumoniae. Asecond (convalescent) blood test is required to diagnose all primary infections. To diagnose all reinfections, paired sera should be tested by complement fixation.Summary: Manitoba experienced an epidemic ofM pneumoniaein 1990–91. Properly selected serological tests can provide a specific and rapid diagnosis.


1949 ◽  
Vol 47 (2) ◽  
pp. 132-141 ◽  
Author(s):  
A. M. Blomfield ◽  
R. R. A. Coombs ◽  
N. H. Hole

1. Anti-mallein sera produced in thirteen species of mammals (including man) and one species of bird have been examined by the haemolytic complement fixation test using guinea-pig complement, and by the conglutinating complement absorption test using pig, horse and cat complements. Two methods of fixation have been used and compared, namely, fixation for half an hour at room temperature and fixation overnight at 4° C.2. The complement of the horse proved to be the most sensitive in nearly every case in demonstrating the specific antibodies in the different sera; in the few instances where it was not markedly the most sensitive it was for practical purposes the equal of any other complement used, independent of the method of fixation. This is clearly indicated in the text figures.3. The effects of overnight fixation on the titres obtained with the different complements are discussed.4. The sera of six fowls inoculated with mallein failed to show fixation of any of the four complements in the presence of the homologous antigen. The presence of immune bodies was demonstrated however by the Indirect Complement Fixation technique of Rice (1948b).


1962 ◽  
Vol 8 (4) ◽  
pp. 545-554 ◽  
Author(s):  
A. E. Kelen ◽  
L. Ayllon-Leindl ◽  
N. A. Labzoffsky

The principle of the indirect fluorescent antibody-staining procedure was adapted for use in the serodiagnosis of toxoplasmosis and the technique compared with other serological tests most commonly employed at present.The results obtained with normal and immune rabbit sera as well as human patients' sera indicate that the indirect fluorescent antibody test for toxoplasmosis is specific in a degree comparable to the complement fixation test, and is sensitive enough for routine laboratory use, its sensitivity being somewhat higher than that of the complement fixation test. The Sabin–Feldman dye test gave positive results with human sera from cases clinically unrelated to toxoplasmosis much more frequently and usually in higher titers than did the complement fixation and the fluorescent antibody tests. On the other hand, the dye test showed a few negative results on sera for which the other tests proved to be positive. The indirect fluorescent antibody test for toxoplasmosis is safer and simpler to perform than the dye test, as living organisms are not used in the test, and prepared smears of killed toxoplasma suspension on cover slips can be kept antigenically active in the frozen state for at least 6 months.The indirect fluorescent antibody test for toxoplasmosis is recommended for use in the serodiagnosis of toxoplasmosis either as a single test or as a supplementary test for checking complement fixation negative sera or the results obtained by the dye test.


Sign in / Sign up

Export Citation Format

Share Document