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Biomedical subjects

M Hagedorn

Publications and source records attributed to M Hagedorn.

At least 109 records · Page 6Linked to original sources
PubMed1977

Effects of arsenic cell metabolism and cell proliferation: cytogenetic and biochemical studies.

Chromosome analysis of lymphocytes from patients who had been exposed to arsenic showed frequent structural and numerical aberrations, even with an interval of decades since the last exposure. The in vitro addition of sodium arsenate induced the same chromosome changes--even to extreme of chromosome pulverizations--upon lymphocyte cultures from healthy subjects. Radioactive incorporation studies showed that arsenate was able to inhibit dose-dependently the incorporation of radioactively labeled nucleotide in RNA and DNA. Beyond that, arsenic blocked the cells in the S- and G2-phase. A general explanation for the inhibitory effect of inorganic arsenic on cell metabolism is the known strong affinity of arsenic to enzymes, especially to those containing sulfhydryl groups.

Aged↗
PubMed1976

Comparative studies of the incorporation inhibition of radioactive nucleotides and amino acids in vitro under the influence of adriamycin, bleomycin, and sodium arsenate.

The incorporation of 14C-marked nucleotides and amino acids into the nucleic acids and into the cellular protein of PHA-stimulated human lymphocytes was inhibited variably by increasing doses of Adriamycin, Bleomycin and Na2HAsO4. The findings, which were obtained with the aid of the liquid scintillation counter and partly by means of 14C-thymidine-marked autoradiographies shows clearly that Adriamycin causes the strongest incorporation inhibition. In contrast to this, the inhibition caused by Bleomycin and arsenate is considerably less destructive. It was shown by means of cytophoto metrical examinations that Adriamycin is capable of fixing cells in the G2 phase and in the S phase. Cells react similarly to Bleomycin and arsenate. The differential inhibition of nucleic acid and protein metabolism induced by Adriamycin, Bleomycin and arsenate is correlated with a varying responsiveness of lymphocytes to the cytostatically effective substances.

Arsenates↗
PubMed1976

[Recurrent skin tumors and their surgical management].

Recurrences of basal cell carcinomas and squamous cell carcinomas are possible in cases of radiation before surgical treatment. This inadequacy occurs in general, if the emphasis of the treatment was on the cosmetical point and therefore the necessary radical therapy had been neglected. Furthermore cicatrizing basal cell carcinomas are prone to recurrences, after only a macroscopical tumor extirpation had been carried out. In special cases of epidermal tumor recurrences our dermato-surgical proceedings are demonstrated. The repair of large skin defects, caused by surgical treatment, requires methods of plastic and reconstructive surgery. Should there be any doubt whether the therapy is radical enough, material for microscopical examination should be taken immediately.

Aged↗
PubMed1976

Monocytopoiesis in chronic eczematous diseases, psoriasis vulgaris, and mycosis fungoides.

Monocytopoiesis and blood monocytes were examined in 8 patients with disseminated chronic eczematous diseases, 8 patients with disseminated psoriasis vulgaris, and 8 patients with mycosis fungoides in plaque or tumor stage. Monocytopoiesis was moderately stimulated in all these patients. The stimulation manifested itself by: (1) a rise in relative number of promonocytes in bone marrow in all patients with eczema, in 1 out of 8 patients with psoriasis, and in 7 out of 9 examinations in patients with mycosis fungoides; (2) a rise in [3H]thymidine labeling indices of medullar promonocytes (8/8 eczema, 7/7 psoriasis, 8/9 mycosis fungoides); and (3) a rise in the naphthol-AS-D-chloroacetate esterase activity of blood monocytes, indicating premature monocyte marrow egress (3/5 eczema, 7/8 psoriasis, 9/9 mycosis fungoides). In eczema and psoriasis the mean enhancement of monocytopoietic activity was similar but less pronounced than in mycosis fungoides. In the latter disease there was no correlation between measured parameters and visible skin lesions. The results were interpreted as indicative of increased monocyte consumption by pathologic, immunologic, and/or inflammatory processes.

Adult↗
PubMed1975

Myocardial damage during protracted anaphylactic shock in guinea pigs.

In ovalbumin-sensitized, mepyramine-treated guinea pigs protracted anaphylactic shock was elicited by i.v. injection of antigen. Diffuse or focal necrosis of myocardial cells was found in animals which died in protracted shock, as well as perivascular and interstitial edema. The antigen effects could be partially imitated by i.v. infusion of high amounts of adrenaline into nonsensitized guinea pigs. When adrenaline was infused during protracted anaphylactic shock, the catecholamine effects did not add to the histological effects of the antigen. Rather, the morphological alterations in the hearts were reduced, whereas the survival times were not increased, but decreased. - The findings are discussed in view of the nature of protracted anaphylactic shock.

Anaphylaxis↗
PubMed1975

[Fumaric acid monoethylester: Effect on DNA-synthesis and preliminary findings in experimental studies in animals (author's transl)].

The incorporation of 14C-Thymidin into DNA of cultured human lymphocytes is depressed by added fumaric acid monoethylester (FSME) depending on the dosage of FSME. The decreased radioactivity in DNA as measured by scintillation counting is paralleled by a concomitant decrease in the labelling index in autoradiograms. Decreasing radioactivity is therefore due to a lower number of DNA synthesizing cells. No selective inhibition of proliferation during one of the cell cycle phases was observed. Especially a G2-block known from other cytostaties is absent. A mean dosis of 6.88 mg FSME per g body weight administered intraperitoneally is lethal to mice. The animal die from diffuse necroses of heart muscle cell. Alterations of other organs are less prominent. At lower doses of FSME the morphology of the organs investigated is altered to a smaller degree.

Animals↗
PubMed1975

Mycosis fungoides with marked brain involvement--a case report.

The clinical course of a patient with mycosis fungoides, which could be confirmed histologically in the premycotic stage, 2 years after the onset of the disease is reported. The disease led to death after a further 3 years, during which the infiltrative and tumorous stage had appeared. At autopsy, apart from the skin changes typical for mycosis fungoides, involvement of the pia mater, plexus chorioideus, cerebrum and cerebellum was established. This constituted the only manifestation of the disease in the internal organ systems. There were no detectable neurological defects.

Adolescent↗
PubMed1975

Pathogenetic aspects of bromocarbamide intoxication.

In bromocarbamide intoxication in humans, as in rabbits, the predominant feature is the endothelial damage characterized by desquamation and vacuolisation, followed by interstitial oedema. Consumption coagulopathy, as observed in some cases of human bromocarbamide intoxication and also in our experimental model, can be prevented by anti-coagulant therapy with heparin and also, as could be shown in rabbits, with aggregation-inhibiting agents. These findings strongly suggest that consumption coagulopathy is only a secondary phenomenon which develops in the course of primary endothelial damage. Similarities in the histological findings of endothelial damage between bromocarbamide intoxication in humans and in rabbits and the so-called "Adalin purpura", which can be observed after chronic use of bromocarbamide, are discussed.

Animals↗
PubMed1975

[Intravital microscopy and post mortem histology of burn shock in rabbits (author's transl)].

This paper describes results of intravital microscopic observations of the mesenteric blood and lymph vessels of the rabbit. 20% of the surface of the skin of these rabbits were burned. Immediately after producing the shock, general unspecific symptoms were seen: decrease of circulatory flow, aggregates of erythrocytes. Specific alterations consisted in leukocyte sticking, platelet aggregation, hemolysis and stasis. Vascular spasm and hemorrhage were conspicuously absent. These microcirculatory features were compared with those of different forms of shock. There was a striking similarity with the characteristics of the burn shock with the endotoxin shock. On the other hand hemorrhagic and traumatic shock exhibited similar phenomena, thus forming a second distinct group of shock as seen from a microcirculatory point. Differentiation between the groups is only possible from the specific features of microcirculation failure. These results confirm the view point, that different forms of shock evoke different pathological reactions in the terminal vascular bed.

Animals↗