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E Habermann

Publications and source records attributed to E Habermann.

At least 109 records · Page 6Linked to original sources

A radioimmunoassay for tetanus antibodies using protein A - containing Staphylococcus aureus.

To measure tetanus antibodies a trace amount of 125I-labeled tetanus toxin is mixed with appropriate dilutions of human serum or blood. The labeled antigen-antibody complexes are adsorbed to heat-killed staphylococci (Cowan I) via their surface protein A. The radioactivity of the washed solid phase is a function of the initial antibody concentration. The test allows the measurement of 6 X 10(-0) U of tetanus antitoxin in a volume of 0.03 ml. In order to avoid possible interferences, serum has to be diluted 20-fold before use. Taking that into account, the real border limit of sensitivity is 4 X 10(-3) U/ml serum. Antibodies may be measured in serum, in plasma, and even in heparinized blood. As to its sensitivity, the test compares well with the toxin neutralization procedure. It is superior to the previous radioimmunologic, enzymoimmunologic, and hemagglutination techniques with respect to sensitivity and reproducibility. It reflects the values obtained in the toxin neutralization test better than the other in vitro procedures, as shown by parallel assays of 17 sera.

Humans↗

[Snake bites].

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Humans↗

Histoautoradiography of central nervous system in rats with generalized tetanus due to 125I-toxin.

Rats were injected i.v. with 125I-tetanus toxin. In autoradiographs of the spinal cord radioactivity was found over the pericarya and in the surroundings of the motoneurones whereas grain density was less over their nuclear region. In addition, pericarya in the lateral horn of the thoracic region and also the bipolar cells of the spinal ganglia contained radioactivity. The central part and the dorsal horns of spinal cord, and the white substance did not show any appreciable radioactivity. Within the medulla oblongata, clusters of large cells representing motor nuclei, as well as some fibre tracts close to them, contained 125I. Forebrain and cerebellum remained free. According to its histoautoradiographic appearance, generalized tetanus can be described best as a combination of multiple local tetani.

Animals↗

Neurotoxicity of apamin and MCD peptide upon central application.

Besides apamin, the structurally related MCD peptide (mast cell degranulating peptide; peptide 401) is another centrally acting peptide from bee venom. In contrast to apamin, it is hardly neurotoxic upon intravenous injection in mice. Following intraventricular injection, as little as 0.3 microgram/animal produce convulsions and respiratory arrest in mice. The clinical picture differs from that elicited by apamin, and apamin is about 10 times more potent than MCD peptide when given intraventricularly. Apamin and MCD peptide injected into the spinal cord of rats in nanogram amounts, produce circumscript hyperexcitation lasting more than one day, however with complete recovery following sublethal doses. Local apamin poisoning differs from local tetanus (elicited by the same way) by its faster time course.

Animals↗

Preparation, measurement and possible use of human antitoxin against Cl. botulinum A, B, and E toxins.

Human antibodies against botulinum toxins A, B, and E have been raised by repeated injections of pentavalent toxoid in a healthy volunteer. The final titer was 3.2 U anti-A, 0.4 U anti-B, and 2.5 U anti-E/ml. In mice, the efficacy of the antitoxin decreases with the time between poisoning and application of the antiserum. The dose recommended for prophylactic purposes in man is 1 ml/kg. In overt poisoning, therapy should be started with higher titer animal serum since in animal experiments high titer sera can stop (although not reverse) the symptoms of overt botulism within an-admittedly not too broad-rnage of time and dosage. Later on, therapy can be continued with human antiserum. An inverse radioimmunassay for botulinum A antitoxin using labeled botulinum toxin and antibody-coated tubes is described. The serum is available upon request from the author.

Animals↗

Direct evidence for the specific fixation of Cl. botulinum A neurotoxin to brain matter.

Rat brain homogenate and synaptosomes from rat brain bind botulinum toxin. The binding is accompanied by partial inactivation. The binding decreases with increasing ionic strength. A considerable fixation of tetanus toxin can still be demonstrated under conditions which prevent the fixation of botulinum toxin. 2. Only the grey substance, not the white substance from bovine brain is able to bind the toxin. 3. Upon pretreatment with neuraminidase, synaptosomes lose nearly all of their binding capacity. However, neither gangliosides nor ganglioside-cerebroside mixtures nor brain extracts could replace the synaptosomes. Thus botulinum A toxin closely resembles tetanus toxin in its ability to react with (a) neuraminidase-sensitive site(s) of the grey matter of the CNS. It differs from tetanus toxin by its stronger sensitivity against ionic forces and by its failure to react with certain gangliosides.

Animals↗

The renal handling of biologically active peptides.

With the use of the protease inhibitor from bovine organs--Trasylol-- as a model, we studied the pinocytic transport of peptides in the kidney. Rats were injected with the 125I-labeled peptide and killed at different times thereafter. Kidney homogenates were subfractionated by differential and sucrose gradient centrifugation. Radioactivity was measured in the fractions in order to study the time-dependent fixation of the peptide to different cell organelles. With short survival periods, the protease inhibitor is recovered in the brush-border fraction, with longer periods, a shift towards the lysosome fraction takes place. Thus, the renal transport of the protease inhibitor consists of three steps: binding to the brush border, incorporation in micropinocytic vesicles and transport in phagolysosomes.

Animals↗