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PubMedDate not supplied

[Comparative analysis of the antigenic composition of the hemagglutinins of influenza viruses A/England/42/72, A/Port Chalmers/73 and A/USSR/053/74].

The presence of three antigenic determinants was demonstrated by the method of selective adsorption of inhibitor-free sera (HI test) and complement-fixation test (CFT) in hemagglutinins (HA) of influenza A/Port Chalmers/73 and A/USSR/053/74 viruses. These variants with closely similar antigenic composition have two antigenic determinants related with NA of A/England/42/72 virus, whereas the third antigenic determinant is specific only for them and is lacking in A/England/42/72 virus NA. According to the results obtained the antigenic composition of HA of these viruses may be designated in the following way: A/England/42/72--H3 H6 H7, A/Port Chalmers/73 and A/USSR/053/74--H3 H7 H8. A method is suggested for preparation of monospecific serum to the antigenic determinant H3 common to all variants of the Hong Kong variety of influenza virus. This serum is free from nonspecific inhibitors, contains no antibody to the host cell antigens and may be used both in CFT and HI test for rapid identification of new influenza virus isolates.

Antigens, Viral↗
PubMed1984

Consistent patterns in the contact of domestic animals with tick-borne encephalitis virus in the eastern part of the Russian plain.

Hemagglutination inhibition test (HIT), neutralization test (NT) and complement fixation test (CFT) were used to serologically examine goats and cows in the southern area of the Kirov region and in the Udmurt ASSR. A total of 1641 sera of goats and 1414 sera of cows were examined for the presence on antibodies against tick-borne encephalitis virus. The tests showed a relatively intensive contact of goats and cows with TBE virus in the forests of the eastern part of the Russian Plain: HIT was positive in 27% of goat sera and 17% of cow sera, virus-neutralizing antibodies were detected in 25% of sera of goats and the positivity of CFT was recorded in 32% of goat sera and 29% of cow sera. The relative number of immune animals differed considerably from locality to locality. The localities with great numbers of immune animals were characterized by a distinct increase in the incidence of adult ticks Ixodes persulcatus. The immunization of domestic animals in the natural foci of infection was found to be season-dependent: the highest immunity rates were observed at the end of summer and in the autumn. The seasonal variations in animal immunity are demonstrated in detail on adult goats. Towards the spring time some serum antibodies, namely virus neutralizing antibodies and antihemagglutinins, tended to disappear in a certain number of animals. A similar, but somewhat different pattern of immunization could be observed in cows. In contrast to goats, cows appeared to be less susceptible to the tick-borne encephalitis virus infection, which was substantiated by both serologic data obtain in this study and the data reported in the literature. In the natural foci of TBE virus infection grazing goats and cows had the most intensive contact with the pathogenic agent in the first year of their lives.

Age Factors↗
PubMedDate not supplied

[The background of the serological cross-reaction between Yersinia and Brucella and the possibility of differential diagnostics by the ELISA technique and the electroimmuno assay (rocket electrophoresis) (author's transl)].

A strong serological cross-reaction appears between different species of genus Brucella and Yersinia enterocolitica (Y.e.) serotype 0--9, which seriously complicates the diagnostic works of brucellosis and yersiniosis both in humans and animals. This cross-reaction makes it impossible to perform a differential serological diagnosis using common routine procedures such as the agglutination test and the complement fixation test. By the use of immunological, immunochemical and structural chemical methods it has been shown that the common antigenic structures of Brucella and Yersinia are situated in the lipopolysaccharides (LPS) of the cellwalls. In order to do structure analysis gaschromatography in combination with mass spectrometry of LPS from Brucella and Yersinia bacteria has been achieved. The results show that two monosaccharides (glucose and galactose) constitute common components of the LPS-molecules. A discovered cross-reaction between Y.e. 0--9 and Salmonella urbana (0--30) confirms the hypothesis that glucose and galactose are responsible for the serological cross-reaction between Brucella and Y.e. 0--9. An enzyme-linked immunosorbent assay (ELISA) has been developed in order to be used as a differential routine test. The results show that by using ELISA, a differentiation between antibodies against Y.e. 0--9 and B. abortus can be done with high sensitivity and accuracy. Another differential diagnostic system has been developed by the use of electroimmuno assay (rocket electrophoresis). This method raises the possibility of a rapid and a simple qualitative differentiation of antibodies against Brucella and Yersinia.

Agglutination Tests↗
PubMed1995

[Occurrence of Coxiella burnetti antibodies in cattle, sheep and small terrestrial mammals in the western region of Bohemia].

The prevalence of antibodies to C. burnetii was studied in the Karlovy Vary district (the Czech Republic) between 1987 and 1989. Sera of cows, sheep and heart eluates of small ground mammals were tested using the complement fixation test with C. burnetii antigen in phase II (Bodibion, Mevak Nitra, Slovakia). Titers greater or equal to 8 or 10 were considered as positive. Cows from two large-scale farms were tested four times (the average number of every sampling was 339 cows). Their seroprevalences varied from 0.3 to 4.3% and from 0.3 to 10.6% on the first and second farm, respectively. The highest seroprevalences were on both farms in July, 1987. No clinical signs of Q-fever were observed in cows from these farms. In May, 1988, sera of 96 sheep from two farms were tested. No antibodies to C. burnetii were detected. A total of 488 small ground mammals from 9 various localities was tested. Antibodies were ascertained in one Common Vole (Microtus arvalis) at a titer of 10 and in one Bank Vole (Clethrionomys glareolus) at a titer of 2560. At present, some strains of C. burnetii occur in cattle and small ground mammals in the study area but these strains do not cause the clinical Q fever as they did in the same area at the beginning of the fifties.

Animals↗
PubMed1995

Prevalence of antibodies to Toxoplasma gondii in army dogs in the Czech Republic and Slovak Republic.

Army dogs, mostly German Sheep-dogs, were tested for antibodies to T. gondii using Sabin-Feldman dye test (DT) and complement fixation test (CFT). Titers greater than or equal to 4 and 10 were considered as positive in DT and CFT, respectively. Seroprevalences in the group of 720 dogs from the civil sector of different areas in the former Czechoslovakia were 39.3% and 15.4% in DT and CFT, respectively. During dogs' stay in army seroprevalences decreased only slowly. The decrease was probably due to less possibility to contact sources of infection--dogs were fed with cooked food, kept in pens with a high level of hygiene, and cats were very rare there. Nevertheless, some dogs in the army training centre were infected by T. gondii in that way of dog rearing.

Animals↗
PubMed1994

Diagnosis of Babesia caballi infections in horses by enzyme-linked immunosorbent assay (ELISA) and western blot.

From Babesia caballi in vitro cultures a preparation of 100% infected erythrocytes was obtained. From this, B. caballi antigens were extracted with the detergent 3-[(3-Cholamidopropyl)-dimethylammonio]-1-propane-sulfonate (CHAPS) and used as ELISA antigens. A control antigen of normal erythrocytes from the same donor horse was prepared in an identical manner. The ELISA and Western blot were validated by testing of sera from horses experimentally infected with B. caballi or B. equi or not infected with Babesia spp. ELISA and Western blot results were compared with those obtained by the immunofluorescence antibody test (IFAT) and complement fixation test (CFT). The sensitivity of the ELISA of 98.3% obtained for sera from day 14 after infection was superior to the Western blot (94.9%), the IFAT (96.6%) and the CFT (28.8%). No positive results were obtained in the ELISA and Western blot with 106 sera from horses not infected with Babesia spp. resulting in a calculated specificity of 100% for both tests. Cross reactions of B. equi-positive sera did occur to a larger extent in the ELISA (20%) than in the IFAT (4%). No cross reactions were observed with the Western blot and the CFT. The higher sensitivity of the ELISA was also demonstrated by testing of 132 field sera: more positive results were obtained by ELISA (112) as compared to IFAT (92) or CFT (41). The validity of these results was confirmed by testing of sera by Western blot. The ELISA as the most sensitive test provides the best method for the identification of carrier horses to prevent the introduction into non-endemic areas (export testing).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMedDate not supplied

[A comparative evaluation of different immunological reactions in the diagnosis of pseudotuberculosis].

To study humoral response in patients with the generalized form of pseudotuberculosis, the agglutination test, the passive hemagglutination test and the complement fixation test with antigen obtained from "Virion" (Switzerland) were used. The study of the dynamics of antibody formation to outer membrane proteins (OMP) and Yersinia pseudotuberculosis (pYV+ and pYV-) lipopolysaccharide (LPS) revealed that the synthesis of antibodies to OMP, controlled by inv gene, exceeded the synthesis of antibodies to LPS at all periods of the disease, which determined the necessity of further study of the role of OMP in pathogenesis and in the formation of humoral response. On the basis of the study of the occurrence of antigens a high diagnostic effectiveness the enzyme immunoassay for the detection of Y. pseudotuberculosis antigens, mainly at the first stage of the disease, was noted.

Acute Disease↗
PubMed1997

Serological findings obtained in cattle herds immunised with the Brucella melitensis Rev.1 and the B. abortus B19 vaccine in Mongolia.

To reduce the economic losses caused by Brucella abortus infection under the conditions of nomadic cattle breeding, more than half million cattle over 3 months of age (excluding male animals) were immunised with the B. melitensis Rev.1 vaccine in 7 provinces of Mongolia in the first year of a programme (1987). In the second year, only heifer calves over 3 months of age, yearling animals not vaccinated in the first year, as well as heifers over 2 years of age and cows were vaccinated. The vaccine was administered subcutaneously at a dose of 5 x 10(9) viable organisms. In co-operatives that had used the B. abortus B19 vaccine, the existing vaccination programme was maintained, and all cattle over 3 months of age (except male animals) were vaccinated with a dose of 5 x 10(10) viable organisms, using the same vaccination programme as in herds immunised with the Rev.1 vaccine. Before vaccination, two serological tests were carried out at an interval of 20-25 days to determine the incidence of Brucella infection. Serum samples were tested by the Rose Bengal test (RBT), serum agglutination test (SAT) and complement fixation test (CFT). An infection rate of 3.8-35% was found in the herds tested. Animals serologically positive for brucellosis were removed from the herds. Fifteen to 21 days after vaccination, blood samples were taken from 10% of the animals in all immunised herds. The serum samples were tested by SAT and CFT to check the seroconversion rate. In herds immunised with the Rev.1 vaccine 90% of the cows and 92.7% of the heifers were seropositive, while the seropositivity rate of B19-vaccinated cows and heifers was 68.8% and 89.7%, respectively. The serological status of the vaccinated animals was checked not only immediately after vaccination but also 12 months thereafter (in B19-vaccinated cows also 24 months after vaccination). After Rev.1 vaccination, antibodies were present in 7% of the cows, 4.6% of the 3-year-old heifers, 3.1% of the 2-year-old heifers, and 1.6% of the 1-year-old animals. By comparison, 13.2% of the cows vaccinated with the B. abortus B19 vaccine were serologically positive 2 years after immunisation. As regards the B19-vaccinated heifers, 7.9%, 5% and 2.7% of the 3-year-old, 2-year-old and 1-year-old animals, respectively, were serologically positive even 12 months after vaccination.

Animals↗
PubMedDate not supplied

[Immunodiagnosis in 647 suspected clinical cases of toxoplasmosis].

Though Toxoplasma gondii can cause severe pathology in human, in most of the cases it produces only asymptomatic infection. So, it is important to dispose some methods capables to discriminate between acute and chronic infections. An indirect hemagglutination test (IHAT), dye test (DT) and complement fixation test (CFT) were performed in 647 sera from patients suspected of having toxoplasmosis infection. IHAT and DT titer > or = 4 and CFT > or = 5 were considered positive. Titers were classified as follows: low (4-16), median (64-512) and high (> or = 1000) for IHAT and DT. The pathologies for demanding these serological tests were: adenopathies (58), nephropathies (72), neuropathies (30), obstetrical problems (65), opthalmopathies (147), AIDS (237) and miscellaneous (37). Global positivity of 49.5% and 4.5% for IHAT/DT and CFT respectively were found. The positivity for the different groups were: adenopathies (48.3% and 13.8%), nephropathies (43.1% and 1.4%), neuropathies (26.7% and 3.3%), obstetrical problems (40.0% and 0.0%), ophthalmopathies (59.9% and 8.2%), AIDS (52.1% and 2.5%) and miscellaneous (40.5% and 2.7%) for IHAT/DT and CFT respectively. Low and median titers for IHAT/DT were found in 81.3% of cases. A high agreement in frequency of concordant and discordant titers of IHAT/DT and CFT, indicating a recent or acute infection was observed. This fact was more relevant in adenopathies, ophthalmopathies (uveitis) and AIDS groups.

Adolescent↗
PubMed1975

[The antigenic structure of Toxoplasma gondii. III. Behavior of human sera as compared with purified antigens].

263 human serum samples obtained from 9 controls and 42 patients with clinical diagnosis suggestive for toxoplasmosis were examined by means of Sabin and Feldman's dye test (DT) in comparison with complement fixation test (CF) with a whole toxoplasma antigen. 6 out of 9 controls and 21 out of 42 patients showed analogous behaviour in both methods while the remaining ones behaved differently. 24 out of the 42 patients as well as the 9 controls were chosen between these two groups (showing concordant or discordant DT/CF behaviour) to determine the presence or absence of anti-"polysaccharide" and anti-"protein" antibodies against purified antigens by means of CF test. Presence of anti-polysaccharide antibodies was shown in 15 subjects (4 out of 17 "DT/CF discordant" groups) and antiprotien antibodies in 8 patients (2 and 6 respectively in the two groups). Antibodies against these two purified antigens were never shown in the 9 normal people. Critical as well as hypothetical implications concerning the results so far obtained are discussed.

Antibodies↗
PubMed1975

[Autoimmune factors in cerebral circulatory disorders associated with hypertension and atherosclerosis of the cerebral vessels].

In 160 patients with disorders of brain circulation in cerebral atherosclerosis, 68 normals and 38 patients with different neurological diseases (a control group), a special study was undertaken to study the antibrain antibodies with the aid of a complement fixation test (CFT), and a test of complement utilization (CUT). Positive results in the CFT and CUT were seen in patients with ischemic strokes and transient disorders of brain circulation. The formation of antibodies to brain tissues depends upon their type, duration of the disease and is more characteristic of the rehabilitation period. In studying autoimmune processes in patients with disordered brain circulation previous diseases should be taken into consideration (brain trauma, epilepsy, strokes). The existence of antibrain antibodies correlates with the intensity of the process.

Adult↗
PubMed1983

Seroepidemiological survey of maedi-visna virus infection in sheep and goat flocks in Quebec.

Maedi-visna, a chronic viral disease of adult sheep characterized by progressive dyspnoea or neurological manifestations, was first recognized and described clinically in Canada in 1970. Seroepidemiological study was conducted in sheep and goats in various areas of Quebec. Sera of 10% of the animals of selected flocks were collected and specific antibodies against maedi-visna virus were tested by a modified direct complement fixation test. Results show seropositive rate of 67.6% for Sherbrooke sheep; of 40.5, 41.1 and 47.1% for Quebec, Saint-Hyacinthe and Nicolet sheep respectively and only 29.2 and 20.0% positive sera in l'Assomption and Rimouski animals. Prevalence rate of positive goats varied according to geographic areas (0 to 36.8%). Statistical analysis of various factors, e.g. age, breed, mode of raising, origin and size of flock showed no relation between these factors and the geographic areas. But, some clinical problems in the sheep flocks such as cough, rapid breathing, mortality and abortion were associated with high infection rate (greater than or equal to 50%) to maedi-visna virus. In goats, no correlation was demonstrated between these clinical signs and serological results. Our results suggest that it is important to consider this disease in an adequate program of preventive medicine in Quebec.

Animals↗
PubMed1977

Uterine toxoplasma infections and repeated abortions.

Serologic testing for Toxoplasma antibodies (dye test, indirect fluorescent antibody test on serum, and complement-fixation test) was done in 96 women with habitual abortions and 61 women with sporadic abortions. In 61 of these women, endometrial biopsies were examined for content of T. gondii (animal inoculation procedures, immunofluorescence microscopy). Control subjects were 59 women with no spontaneous abortions. In seven patients (one control patient and six with habitual abortion), tachyzoites of T. gondii were observed in repeated biopsies from the endometrium and in menstrual blood by the immunofluorescence method. In no case, however, could T. gondii be isolated from the endometrium by inoculations. Moreover, the serologic results obtained among the patients with habitual abortion did not differ significantly from those obtained among the ones with sporadic abortion or among the control subjects. Five of the women with Toxoplasma-positive endometrium were serologically negative. Treatment of the Toxoplasma-positive women with antitoxoplasma drugs led to removal of parasites from the endometrium. T. gondii was not observed in the semen of the husbands.

Abortion, Habitual↗
PubMed1979

Complement fixing activities of normal mammalian sera for homologous and heterologous sperm.

The species of the natural anti-sperm antibodies found in normal mammals have been assessed using complement fixation tests. Heated rabbit sera showed complement fixing activity with both rabbit and guinea pig sperm, indicating that rabbit natural anti-sperm antibodies do not show clear cut species specificity in these interactions. On average, rabbit sera reacted more strongly with rabbit sperm that with guinea pig sperm but the difference fell short of statistical significance (P < 0.05) and there was considerable variation between sera in their anti-sperm activities. There were, however, clear species differences between rabbit and guinea pig sera in that heated guinea pig sera showed significantly weaker anti-sperm activity than heated rabbit sera (P < 0.005). Mouse vas sperm showed greater complement fixing activities (in combination with mouse serum) than did epididymal sperm (P = 0.05). These results are discussed in relation to possible functions of natural anti-sperm antibodies.

Animals↗
PubMed1995

[Hypersensitivity pneumonitis caused by a home humidifier].

A 33-year-old man was admitted complaining of a fever, dyspnea, and a dry cough almost every night since December of 1992. He had been using an ultrasonic humidifier at home. The chest CT scan and roentgenogram showed bilateral reticulonodular shadows. After admission, the symptoms resolved spontaneously. These findings were suggestive of hypersensitivity pneumonitis. After analysis of fluid obtained by bronchoalveolar lavage and of a specimen obtained by transbronchial biopsy, "humidifier lung" was diagnosed. Ten species of microorganisms were isolated from the water left in the patient's humidifier. On precipitation and complement fixation tests of the patients serum, the results were positive for three of those microorganisms: Flavobacterium multivorum, Yersinia pseudotuberculosis, and Aureobacterium liquefaciens. The titer on the complement fixation test increased immediately after a provocation test. The laboratory results suggest that at least one of these three microorganisms was the causative antigen in this case.

Adult↗
PubMed1976

[Epidemiology of human and animal brucellosis in western Africa. The results of six studies in the Ivory Coast, Upper Volta, and Nigeria].

Brucellosis has a two-fold importance in public health: the transmission of the disease to man by contact with animals or ingestion of raw milk is of direct importance; of indirect importance is the loss of animal protein. The authors have carried out ten epidemiological investigations in different bio-climatic zones of West Africa. More than 120 villages were evaluated. In each village, 100 persons were chosen at random and all or part of the animal population was also studied. Three tests were used for man: the melitin intradermal reaction, the sero-agglutination test of Wright and the complement fixation test. Three tests were used for the animals, the "ring-test" and the same serologic tests used for humans. The results indicated that brucellosis in animals exists in all regions but with varying rates. The bovine species seems to be the most contaminated. The enzooty becomes more widespread towards the South. Human brucellosis was not found to be of great importance in the regions mainly populated by farmers. Shepherds and their families in these zones, however, were found to have been infected. The highest percentage of infected humans was found in the sahelian zone (in Dori 30% of the intradermal reactions and 10% of serologies were positive for humans) in spite of a rather low infection rate among animals (6%-8% ring-tests positive among cattle). The majority of the population are shepherds and close cohabitation with animals is common. A basic dietary constituent is milk, which is often consumed raw (variable according to ethnic group), and provides the principal source of animal protein. Adults were found to have a significantly higher intradermal reaction rate in most of the regions studied. The positivity rate was higher in men than in women. In non-pastoral areas the shepherds and their families had a singificantly higher positivity rate than the general population. Ethnic differences were found. Also considered in this paper are intradermal reaction sizes, the relation between intradermal and serologic results, the modes of human transmission of the disease, and the relationship between human and animal forms of brucellosis.

Adult↗
PubMed1978

International standard for anti-Brucella abortus serum: comparison of the complement-fixing activity of the first and second international standards and the EEC standard.

Although the three standards have similar agglutinating activities, it was found that the first International Standard had about half the complement-fixing activity of the second International Standard and the EEC standard. The complement-fixing activities of the latter two standards were similar. On the basis of these results, showing that the agglutination and complement-fixation tests measure different biological activities in anti-Brucella abortus sera, the WHO Expert Committee on Biological Standardization in 1976 assigned separate unitages of agglutinating and complement-fixing activity to the second International Standard for Anti-Brucella abortus Serum.

Agglutination Tests↗
PubMedDate not supplied

Studies of flocks with high mortality from lymphoid leukosis.

Two pairs of commercial white-egg parent flocks were selected for study, because one of each pair was observed to be dying with lymphoid leukosis at a high rate. The proportion of each flock producing eggs with lymphoid leukosis virus in the albumen was studied. In one pair the rate of birds shedding was no different in the high- and low-mortality flocks. The total rate of shedding was lower in the other pair, but the rate was higher in the high-mortality flock. These data indicate that the rate of virus infection is not always proportional to the development of lymphoid leukosis, and that other environmental factors may play a role. Direct complement-fixation tests on the albumens which were positive for lymphoid leukosis virus showed that group-specific antigen could be detected in 83%. Therefore, the direct complement-fixation test can be used on albumens as a rough estimate of shedding rate.

Animals↗