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Biomedical subjects

J Sýkora

Publications and source records attributed to J Sýkora.

At least 19 recordsLinked to original sources
PubMed1992

[Significance of the complement fixation reaction in the diagnosis of the acute phase of lymphatic toxoplasmosis].

In a group of 300 sera of subjects with clinically suspect nodular toxoplasmosis the authors tested by the IgM ELISA reaction in the reverse order the importance of the complement-fixation reaction for assessment of the acute stage of the infection. In view of the revealed prolonged detection of IgM antibodies the authors used quantitative evaluation of the reaction; they consider based on a probability pattern of antibody response coefficients of 10 and above important for differentiation of a recent infection. For the suggested method of evaluation it was confirmed that low CFR titres (1:8, 1:16, 1:32) imply usually (89.5%) latent infection, titres of 1:64 chronic (42.8%) and latent infection (57.2%); in no instance onset of the disease was involved. From the titre of 1:128 onwards there is a proportional increase of the probable detection of acute infections (titre 1:1024 as much as 72.7%. However, even high titres are not unequivocal evidence of recent infection. In view of the equivocal interpretation of results of the CFR the authors recommend for assessment of the acute stage of the nodular form of toxoplasmosis examination of the suspect subject by the CFR and in case of a medium or high level assessment of IgM by the ELISA method focused on the level and dynamics of the coefficient.

Acute Disease↗
PubMed1992

[Cryptosporidium species in persons with HIV infection].

Oocysts of Cryptosporidium sp. were detected in the faeces of 65 subjects with the HIV virus, using the concentrating flotation method in a sugar solution and differential staining with methyl violet. In positive cases (a total of 16 subjects) continuous as well as intermittent excretion of oocysts in faeces was recorded, the longest excretion period being up to 15 months. The presented findings of oocysts confirm that Cryptosporidium sp. is a common intestinal pathogenic organism in the investigated group of subjects, and with regard to its pathogenity and opportunistic character they must be subjected to regular parasitological examinations.

Animals↗
PubMed1992

Toxoplasmic antibodies in sera of HIV-infected persons.

The sera of 67 HIV-infected persons without clinical signs of Toxoplasma gondii infection and sera of 777 immunocompetent persons from three distinct regions of Czechoslovakia were examined for the presence of toxoplasmic antibodies using the complement-fixation test (CFT). Additionally Toxoplasma positive HIV+ individuals were re-examined for the presence of IgG and IgM toxoplasmic antibodies by ELISA methods. Results show that overall prevalence of toxoplasmic antibodies is not significantly greater in HIV-positive subjects (29.8%) than in the general population (26.1%). Similarities between these two tested groups were also documented by a close correlation of their geometrical means of titres (13.9 versus 14.5). All 20 HIV-infected patients who were positive in CFT were positive in ELISA IgG reaction, and none in ELISA IgM reaction. The detected antibody levels were suggestive of a latent Toxoplasma infection only. But because of the risk of the infection reactivation all of these patients should be attended to on a systematic basis.

Adolescent↗
PubMed1991

[Induction of experimental pneumocystosis, detection and primary isolation of Pneumocystis carinii].

The described model of experimental pneumocystosis is based on the induction of natural latent infection of P. carinii in Wistar strain laboratory rats. As to pharmacological inducing agents immunosuppresive preparations such as Hydrocortisone sol. inj. (Spofa), Cyclosporin A (Merck) and Dexamethasone (Spofa) were used whereby the latter was effective in up 50%. As to non-pharmacological inducing agents, the authors used in combination with the tested inducers a low protein diet (less than 8% protein in the diet); for suppression of associated bacterial contamination tetracycline was added to drinking water. From the infected lungs by two different methods two types of antigens were prepared 1) PCL antigen (Pneumocystis carinii lavage antigen) isolated by rinsing of the lungs and 2) PCWD antigen (P. carinii whole digest antigen) isolated by digestion of the lungs with collagenase and trypsin. Cysts of P. carinii were detected by staining according to Giemsa (staining of internal structures of nuclear cysts) and by modified staining with toluidine blue O (staining of the cyst wall). For isolation of the antigen and for detection of cysts a combination of the two described methods seems to be best.

Animals↗
PubMed1990

[Characterization of vertebrogenic pain using the short form of the McGill Pain Questionnaire].

A Czech translation of the short form McGill Pain Questionnaire was tested in a group of patients suffering from pain of vertebrogenic origin. The results support the hypothesis that the questionnaire will be an asset in various disciplines of medical practice. While taking up little time it provides a comprehensive and valid picture of the quality and intensity of pain experienced by the patient. The results indicated that the questionnaire can differentiate between different syndromes of pain and is sensitive to the effect of placebo.

Adult↗
PubMed1990

[Determination of antitoxoplasma IgM antibodies using the ELISA method].

The described ELISA method was developed for the examination of antitoxoplasmatic IgM. It is a double, i.e. 4-layer sandwich with the following layers: 1. anti. IgM antibody, 2. the examined serum in a uniform dilution of 1:100, 3. antigen + antitoxoplasmatic conjugate, 4. combined in a mixture prepared in advance. Thus the reaction is shorter but also more sensitive. The components in all three steps are combined for one hour at 37 degrees C. The entire process takes four hours. With regard to the course of the final answer in this type of ELISA reaction it is better to express the results by the level of the attained plateau of optic density than by a titre. The sera are thus examined in a uniform dilution of 1:100 and the results are expressed by a coefficient, the ratio of optic density of the examined serum to the optic density of the pooled negative control serum. By this evaluation the deviation of the mean is reduced to one half, i.e. V = 12.6%. The coefficient does not depend on the contents of specific IgM in a linear fashion, but an antibody change of 1:2 changes it about 1.55 times.

Animals↗
PubMed1990

[Occurrence of Borrelia antibodies in field hares (Lepus europaeus)].

Using the indirect haemagglutination reaction with an antigenic extract from Borrelia recurrentis, the author assessed in the hare the incidence of Borrelia antibodies, incl. antibodies against Borrelia burgdorferi, the causal agent of Lyme borreliosis, a multisystemic disease with natural foci, a disease transmitted mostly by ticks of the genus Ixodes. Sera of 113 hares from 11 localities in the CSSR examined by this method reacted in 41.6% by titres within the range from 1 : 16 to 1 : 512, only 26.5% sera reacted by titres of 1 : 64 and more. Positive values were recorded throughout the year with a maximum in the summer months, there was no age dependence, the incidence was more frequent in adults than juveniles (28.04% and 22.2% resp.). The mean positivity of the three most frequent localities was 28%, with a variation of +/- 5.3%. Despite the hitherto not proved incidence of Borrelia in positive subjects we may assume, based on crossed reactivity of Borrelia recurrentis and Borrelia burgdorferi and analogously with North American representatives of the hare family, the presence of this infectious agent also in the field hare.

Animals↗
PubMed1990

[Interpretation of antitoxoplasma antibody findings].

Between reactions assessing one class of immunoglobulins and reactions detecting all serum immunoglobulins comprehensively such as CFT, there is, as might be expected, a very poor quantitative correlation and thus in individual sera the result of one reaction cannot be reliably added to the result of another (CFT:ELISA/IgG). Even the correlation between reactions focused on the same Ig class (ELISA/IgG: IFT/IgG) is no better. Among reactions assessing specific IgM we consider ELISA/IgM better than IFT/IgM because there is not the risk of false negativity caused by concurrence of IgG. A combination of ELISA/IgG and ELISA/IgM gives good results as a statistical group: the distribution of results revealed agglomerations of sera corresponding to the assumed age of the infection derived from the generally accepted pattern of antibody formation. The applicability of the combination of these two reactions alone for evaluation of individual sera is a promising procedure but awaits further confirmation. Long-term investigations revealed within two years after infection a marked decline of CFT antibodies in the majority of cases but it was not sufficiently clear in ELISA/IgG. Despite the technical advantages of ELISA reactions, elimination af the CFT reaction is not foreseen in the near future. As the minimal combination of methods which provides adequate information we may consider at the present time CFT for assessment of total antibodies and ELISA/IgM for more marked differentiation of the acute stage. Evaluation of the lowest CFR titres considered hitherto as "practically negative" must be obviously revised in subjects with immunosuppression and organ donors for transplantation.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Effect of cortisone on Toxoplasma gondii infection studied by electron microscopy.

The ultrastructural features of cortisone effect on the early development and formation of Toxoplasma gondii tissue cysts were examined in the brains of experimental mice on days 8-47 post inoculation. The cortisone was injected subcutaneously into mice twice a week: 1) at the early acute phase, 5 days post infection, and 2) at the transition phase of development, 12 days post infection. The disturbed regulation of the host-parasite relationship due to the effect of cortisone showed itself in an increase of T. gondii tachyzoites, cystozoites, and cysts not only by intracellular but also by as yet not described extracellular division. The persisting parasitaemia induced by tachyzoites and the earlier development and differentiation of cysts resulted in the cyst rupture releasing a highly resistant antigen of cystozoite type. The toxoplasmic encephalitis had a lethal effect in all mice. The tachyzoites penetrated into many types of cells, but a predilection of development into cysts was detected in neurons and astrocytes. According to the character of host cells, two types of cysts arose: less resistant electron-transparent cysts in neurons often rupturing or budding and more resistant electron-dense cysts in astrocytes.

Animals↗
PubMed1990

[Clinical contribution of the examination of immunoglobulins and albumin in the feces in children (a group of 610 patients 1-18 years of age].

The authors submit their experience with the examination of immunoglobulins and albumin in the faeces of patients with different diseases of the gastrointestinal tract. The presence of antibodies IgA, sIgA, IgM and albumin were assessed in lavages from the rectum or supernatant of the faeces, using the qualitative method of double immunodifussion according to Ouchterlony. A normal finding is characterized by the presence of IgA, sIgA. For evaluation of the clinical importance and applicability of the examination method the authors draw attention to the importance of asessing the degree of positive or negative correlation between findings and the final diagnosis. The authors present three basic pictures; acute inflammation, chronic inflammation, non-inflammatory exsudation (exsudative enteropathy). They analyze the clinical application of different findings and their practical impact. They give an account of limiting factors in the evaluation of the presence of immunoglobulins and albumin in faeces.

Adolescent↗
PubMed1990

[The occurrence of antibodies to Borrelia in dogs].

Using the method of indirect hemagglutination and an antigenic extract of Borrelia recurrentis the occurrence of antibodies to borrelias was investigated in 169 sera of dogs from two groups with different exposure to vectors. A significant difference in the serum positivity of dogs coming to Prague outpatient veterinary wards (53.7%) and of dogs coming from laboratory packs (20.9%) confirms the participation of dogs in the epidemiology of Lyme borreliosis, indicates the influence of the environment with free living vectors and the frequency of host exposure also in the town agglomeration. The highest occurrence of positivity in summer months--July-August) corresponds to the incidence of vectors, the great infestation of which along with the determined serological positivity is a precondition of the clinical manifestation of dog diseases in the CSSR territory.

Animals↗
PubMed1989

[Determination of antitoxoplasma IgG antibodies using the ELISA method].

The described ELISA reaction is suggested as a method for examination of antitoxoplasmatic IgG antibodies. It is a simple, i.e. three-layer sandwich with the following layers: 1. antigen 2. the examined serum either in serial dilution or single dilution 1:300 and 3. a peroxidase anti-IgG conjugate with a final conclusive step, i.e. a substrate solution with OPD. Sera and conjugate are allowed to bind for 30 mins. at 37 degrees C and the substrate solution with OPD is allowed to act for 15 mins., also at 37 degrees C, and thus the entire reaction lasts about two and half hours. The authors describe alternative procedures with standard serum of a known number of international units (I.U.) or without it, evaluated optically or by a photometer. In the version with standard serum evaluated optically we compare the different localization of equally stained wells in the series of serially diluted (4n) examined and standard serum and thus we assess, based on the different dilutions the number of I.U. in the examined serum. If we compare the sera with the serum standard by means of a photometer, we examine them in a single dilution of 1:300 and compare the resulting optical density (OD) with the calibration curve made with four dilutions of the standard. The calibration curve is plotted on a scale which straightens it approximately at an angle close to the optimal 45 degrees and which makes it possible to take readings of interpolated international units.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

Pilot performance is increased after alternating hypo- and hypergravity states.

An increase of performance of six experienced pilots in a complex in-flight aerobatics test repeated after a period of alternating zero-hypergravity conditions, lasting for 30 minutes, was observed, if compared with the same test before such exposition. There was no difference in the increase of the pilot performance, if the in-flight test was repeated after a period of rest of the same duration. We conclude that in experienced pilots adaptation to a complex in-flight test remains uninfluenced by alternating zero-hypergravity conditions, realized in a light transport plane. Perhaps adaptation to alternating gravity conditions is implemented better than to full weightlessness in experienced subjects. This is to be proved in real space flights.

Adaptation, Physiological↗