PubMed HealthSearch

Biomedical subjects

O Prokop

Publications and source records attributed to O Prokop.

At least 19 recordsLinked to original sources

Stain analysis using oligonucleotide probes specific for simple repetitive DNA sequences.

The use of oligonucleotide fingerprinting is evaluated in practical forensic work, using both artificially and systematically produced stains as well as actual case work material. The probes (CAC5/(GTG)5 are superior because of their individualizing potential in comparatively fresh specimens with little DNA degradation, whereas (GACA)4, still produces substantial information when high molecular weight DNA is lacking. The overall limitations and the advantages of this technology are discussed in detail and compared to the classical minisatellite probes.

Blood Stains

Studies on the use of monoclonal antibodies in the investigation of blood stains contaminated by bacteria.

On the basis of some models (bacteria and animal blood groups), it was demonstrated that monoclonal antibody-preparations obviously possess a much higher specificity against the ABO-properties of human than the usual human antisera or lectins. The behaviour of polyclonal and monoclonal reagents for ABO-determination should now be tested in comparative studies using contaminated blood stain material. The results presented in this paper suggest advantages in using monoclonal antibodies.

ABO Blood-Group System

[The Herbst-Volkheimer effect].

More than 150 years ago the foundations were laid for the so-called HERBST effect which was subsequently forgotten. In the sixties the phenomenon was rediscovered by VOLKHEIMER at the Charité Hospital in Berlin and then reviewed through many experiments and publications. What is meant by the HERBST effect? If an experimental animal or even human being is given a larger amount of maize starch or also biscuits or some other products containing starch, starch bodies can be detected rapidly in venous blood already after minutes or half an hour later and in the urine after one hour and later. The term "persorption" has been coined for this interesting phenomenon. It is indeed surprising that it has met with so little attention. As a matter of fact, it constitutes the basis for our understanding of peroral immunization and of allergies. In the same way, feeding of carbon particles results in their appearance and detection in blood, kidney and urine. The same result is obtained by the intake of diatoms and what is even more important with meat fibres. I hope you are aware of the implications. When Professor NAGAI stayed in Berlin, we tried to receive the phenomenon. Since only a few cell nuclei are necessary for "genetic fingerprinting" we thought that after intake of 200 or 400 g of raw meat the type of food eaten could be determined from the urinary sediment by means of the fingerprint method which would be of forensic significance. Therefore, we eat meat and raw liver and examined the urinary sediment.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

Preparation of high-titre anti-P1 sera for blood typing in man.

For the last 25 years, antisera for testing P1 in man have been obtained by i.v. injections in goats using hydatid cyst fluid from livers of pigs infected by Echinococcus granulosus. Due to the fact that this antigen has become very rare today, efforts have been made by the authors to substitute it by different antigens and to save antigen by modifying the technique of immunisation as well. By this, very high titres up to 1:4096 could be reached after specification absorption.

Animals

[Blood groups and disease].

The inquiry for the sense of blood group polymorphisms (enzyme groups and serum groups included) and their significance for the constitution and also disposition to diseases is for the time being absolutely legitimate. But it is shown that the field--scarcely a new hereditary blood factor has been detected--becomes a subject of speculations, possibly of the teleological kind: "For which purpose is the factor existing?", or even "Why has God made up the factor?". The hypotheses developing on that are often extremely suggestive and incorrect hypotheses on the first opportunity sometimes reappear like a "cork-tumbler". Finally only a few hard facts remain. This is shown with the help of the systems AB0, Duffy, HLA, Hp and Pi.

Antibody Formation

B and T lymphocyte mitogenic properties in a snake venom.

From the crude snake venom of Agkistrodon rhodostoma two mitogenic principles could be detected: A potent T-lymphocyte stimulating anti-beta-D-galactose specific lectin with a molecular mass of about 18 kD and a very strong B-lymphocyte mitogenic factor. Whereas the lectin could be purified by affinity chromatography and characterized as a cell agglutinating, but not precipitating lectin, the highly active B-lymphocyte mitogen could be separated but not characterized. Both factors are much stronger than the mitogens known so far.

Animals

Haptoglobin: an immunoregulatory role in tuberculosis?

A significant correlation was found between levels of haptoglobin in sera from Indonesian patients with tuberculosis and the extent to which these sera suppressed mitogen-driven activation of normal lymphocytes in vitro. As in a previous study we showed that there was an inverse relationship between haptoglobin levels and the circulating lymphocyte count in the same group of patients, it is now suggested that this protein has an immunoregulatory role in tuberculosis. Similar observations have been made by other workers on patients with cancer. There was no difference in the distribution of the 3 allotypes of haptoglobin in patients and healthy subjects nor was there any association between such allotypes and the lymphocyte count, the dermal reactivity to tuberculin or the degree of suppression.

Agglutination Tests

Snake venom lectins: a new group of T- and B-cell mitogenic anti-galactans.

A new group of vertebrate lectins has been discovered in snake venom preparations. These lectins are cell agglutinating, but not glycoconjugate precipitating. The specificity is directed towards receptors with terminal D-galactose, beta-linked. From the crude preparations strong T- and potent B-cell mitogens can be obtained by fractionation. The T-cell mitogenic lectin could be characterized as an anti-galactan, which reacts with group B streptococci of type II, and with the other types only after neuraminidase treatment. For comparison, other lectins have been tested with group B streptococci, too.

Agglutination

[Anti-P1 production in the blood of Columba domestica].

After intravenous immunization of six rabbits with washed red cells from a pigeon (columba domestica), anti-P1 of very good quality was obtained after 8-12 injections. The sera indicate human blood cells of type P1 equally well as do anti-P1 of goat (immunized with echinococci cyst fluid).

Animals

[Determination of haptoglobin by agglutination with anti-Hp on latex particles].

Human sera are able to agglutinate latex particles sensitized with antihaptoglobin serum produced from sheep. The agglutination depends on the haptoglobin types. Similar to the agglutination of T4-streptococci the titer of Hp 1-1 is very low and the titers of sera of the types Hp 2-1 and Hp 2-2 are 1:160 or higher.

Agglutination Tests

[Haptoglobins, streptococcus agglutination and streptococcal infections].

The haptoglobins in man and in mammals react with streptococci bearing the T4-antigen. Hp 2-2 and Hp 2-1 react with high titres like complete agglutinins while Hp 1-1 acts like a blocking antibody. It is surprising to observe the similarity of the behaviour of the haptoglobins and of IgG and IgM. Streptococci carrying Hp 1-1 yield a positive Coombs-test. The Coombs-serum however, is an anti-human-haptoglobin-body from sheep. By means of supplements it has been possible to increase partly considerably the titres of Hp 2-1 and Hp 2-2 against the streptococci.

Agglutination