Search PubMed⌕ Search

Biomedical subjects

H Lehmann

Publications and source records attributed to H Lehmann.

At least 145 records · Page 8Linked to original sources
PubMed1981

Mapping of antigenic sites on human haemoglobin by means of monoclonal antibodies and haemoglobin variants.

Monoclonal antibodies specific for human globin chains have been prepared and the following strategy has been applied in delimiting the antigenic sites involved in antibody binding. The structural sites of the human globin subunit that might be recognised by the monoclonal antibody were deduced from comparisons of the primary structures of mammalian globin chains that did or did not react with the antibody. The involvement of individual residues at these specific sites was subsequently tested by reacting the antibody with abnormal human haemoglobins in which there was either a substitution or a deletion of one of the residues in question. The primary structural site recognised by monoclonal antibody HuHb beta 3-2(an antibody that reacts with the adult haemoglobins from man and macaque monkey, but not with those from baboon and mouse) includes the aspartic acid residue at position 52 of the beta-globin subunit.

Animals↗
PubMed1981

Haemoglobin Leiden in a South African negro. A case report.

A Black patient in whom an acute febrile illness was followed by a haemolytic crisis is presented. Investigation of the haemolytic anaemia showed the presence of an unstable haemoglobin which was found to be haemoglobin Leiden. Those members of the family who were available for investigation also had the unstable haemoglobin but showed no haemolysis. Radio-isotope studies on the patient confirmed haemolysis but showed that the spleen was not the main site of cell destruction.

Adult↗
PubMed1981

[Liver changes in Wegener's granulomatosis (author's transl)].

A 54-year-old woman is described, who had been treated with immunosuppressive therapy for Wegener's granuloma for several years. The clinical course was surprisingly long and benign. An incidental sonographic and scintigraphic finding was a change in the liver which healed at the same time as the lung lesions and which is therefore assumed to have been due to inflammatory involvement of the liver.

Azathioprine↗
PubMed1981

Zinc acetate as a precipitant of unstable haemoglobins.

Whereas the addition of four moles of zinc acetate to one of normal human haemoglobin at pH 7.4 results in a clear solution, addition to unstable haemoglobin results in precipitate formation. Within certain limits no false-positive results are obtained with methaemoglobin, and with fetal haemoglobin. With excess zinc, normal haemoglobin also precipitates, but this process is reversible and can be used for a rapid concentration of dilute solutions of normal haemoglobin.

Acetates↗
PubMed1981

Genetic control of the immune response to myoglobin. V. Analysis of the cross-reactivity of 12 myoglobins with sperm-whale myoglobin antisera of inbred mouse strains in terms of substitutions in the antigenic sites and in the environmental residues of the sites.

The determination of the entire antigenic structure of myoglobin has made it possible to focus attention on the molecular factors controlling and influencing immune recognition. Recently, using antisera raised against sperm-whale myoglobin (Mb) in six different host species and investigating their reactions with Mb from 15 species, we showed that the binding capacity of an antigenic site is influenced by substitutions within site residues as well as within the residues close (within 6.0 å) to the sites. Based on these effects it was possible to correlate, at least in qualitative terms, the expected effects of the substitutions in each Mb and its observed cross-reaction with antisera to sperm-whale Mb. In the present work, these correlations were tested using sperm-whale Mb antibodies raised in four inbred mouse strains and in which the amount of antibodies directed to each antigenic site was determined. The amounts of 125I-labelled antibodies that could be bound maximally be each of 12 Mb variants were determined. Because of genetic control, the response to some antigenic sites was not expressed and therefore permitted us to evaluate with a good degree of confidence the effects of amino acid replacements in various myoglobins upon the reactivity of the sites. The values of cross-reaction expected for each Mb variant from these considerations agreed well with the values found experimentally. The results confirm unambiguously that the major factors affecting the cross-reactions of proteins can be attributed to substitutions within the sites and within environmental residues of the sites.

Animals↗
PubMed1981

[Clinical obstetrics and perinatal mortality in 13 years (author's transl)].

Reported in this paper is a critical analysis of perinatal mortality which dropped from three to 1.1 per cent, between 1966 and 1978. The number of caesarean sections went up from two to 8.25 per cent, over the same period of time, with all indications having been foetal. No direct relationship was evident with intensive heart rate control of the foetus. The number of low-weight infants, that is less than 2,500 g in birth-weight, did not decrease in the period under review, in spite of tocolysis and cerclage. Perinatal mortality was conspicuous particularly for decline in intra-uterine and postpartum foetal deaths. There was a steady drop in uncorrected perinatal mortality, while the corrected figure remained constant over the past four years, though the rate of caesarean sections had been rising continuously. Therefore, perinatal mortality cannot be further reduced by continued increase in the number of caesarean sections. However, less low-weight births as well as improved monitoring and care of pregnant women will be answered to the problem. --Maternal mortality over the entire period under review amounted to 0.39 per thousand, against a total of 17 871 deliveries.

Breech Presentation↗
PubMed1981

[Animal studies on the tolerability of AR-L 115 BS (author's transl)].

Acute and subacute toxicity studies as well as reproduction-toxicologic investigations were carried out on the positive-inotropic substance 2[(2-methoxy-4-methylsulfinyl)phenyl]-1H-imidazo[4,5-b]pyridine (AR-L 115 BS) in various species. No undesirable side-effects or organ damage were observed in baboons after oral application of 2.5, 10 and 30 mg/kg AR-L 115 BS for 13 weeks. Beagle dogs, female miniature pigs and rats had brown-coloured urine after the substance. In miniature pigs and rats this was only observed at high dosage (mini-pig: 10 and 30 mg/kg; rat: 200 mg/kg). Changes in the ECG could be seen in the dose range of 20--40 mg/kg (dog i.v.), 30 mg/kg (dog p.o) and 200 mg/kg (rat p.o). Non-inflammatory mitral valve alterations (i.v. and p.o) as well as spot- and ring-shaped endocardial scleroses underneath the aortic valves in the region of the left cardiac outflow tract (30 mg/kg, p.o.) were found especially in female beagle dogs in the same dose range. The alterations are regarded as being of haemodynamic origin in view of the increased myocardial contractility caused by AR-L 115 BS. Phonocardiographic findings support this view. Besides, several dogs (30 mg/kg) and rats (200 mg/kg) showed myocardial scars. All male miniature pigs which had received 30 mg/kg AR-L 115 BS demonstrated an increase in heart and mitral valve weights. The results of the reproduction-toxicologic investigations gave no indication of an embryotoxic or mutagenic effect for the substance AR-L 115 BS. After comparing the results it can be concluded that the dog is the most sensitive of the species under investigation and that the results obtained in this species should not be generalised. Biochemical tests showed very similar metabolic patterns for AR-L 115 BS in baboons and man. From this it can be deduced that the results obtained in baboons are most likely to be transferable to man.

Administration, Oral↗
PubMed1981

[Method of colpo-urethrocystography. Part II: Physico-technical conditions for optimum colpo-urethrocystography (author's transl)].

The method of colpo-urethrocystography is now increasingly used in hospitals which admit women for treatment of functional urinary incontinence. Both the quality of examination and the resulting value of the method were found to depend decisively on the techniques used. The results of a systematic purpose-oriented methodological study, with 40 cases of colpo-urethro-cystography included, were evaluated, and a resulting examination programme is described which can be out with the facilities available in the GDR. Here are the most important requirements: 1. Availability of fluoroscope with image intensifier, TV connection, and high-voltage generator; 2. Use of hard rays, X-ray exposure system, HS 11 or HS 90 X-ray film, 18 X 24 in format (vertical), in conjunction with highly amplifying sheet; 3. Marking of urinary bladder by means of 250 ml of contrast fluid (20 ml Propyliodon, 40 ml Visotrast 290, 190 ml physiological salt solution) and marking of urethra, using a lipiodol-UF soaked textile wick.

Contrast Media↗