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Biomedical subjects

J Schumann

Publications and source records attributed to J Schumann.

At least 91 records · Page 5Linked to original sources
PubMed1977

[Experimental examinations about the proliferation and radiotherapy after administration of Vincristin and Adriamycin (author's transl)].

Cytophotometric examinations of solid carcinomas of Ehrlich in mice don't show a considerable cyto-cinetic effect after administration of Vincristin. On the other hand, Adriamycin causes in the same tumor a significant stop in the G2 + M phase with a synchronization factor of 1,4 to 1,5 related to G2. The following experiment with the combined Adriamycin and radiotherapy demonstrates with a statistical significance lying about 5% that an immediate radiotherapeutic success can be obtained which is even increased by a partial synchronization. A considerably enriched G2 + M phase as a result of the administration of Adriamyzin is proven by a first cyto-cinetic examination of human cancerous tissue. A possible clinical therapy scheme is discussed.

Animals↗
PubMed1976

[The effect of bencyclane hydrogen fumarate (Fludilate) on the adhesion of tumor cells in vivo and in vitro].

Bencyclane hydrogen fumarate (Fludilat) was tested on the stickiness of tumor cells in vivo and in vitro. It was intended to determine whether Fludilat reduced the cancer cell stickiness in vitro, and if the survival time of cancer cell carrying animals can be increased with Fludilat in vivo, or in combination with a cytostatic. For the in vitro trials, concentrations from 0.001 mg/ml to 1 mg/ml medium were chosen. The survival trial on NMRI-mice with Nemeth-Kellner lymphosarcoma was performed in three groups, each with 4-5 sub-groups: Control group--Fludilat 5 mg, 10 mg, 20 mg/kg bodyweight, Bleomycin--50 mg/kg bodyweight, 100 mg/kg bodyweight, 250 mg/kg bodyweight, Bleomycin 50 mg/kg bodyweight + Fludilat 5 mg/kg bodyweight, Bleomycin 100 mg/kg + Fludilat 10 mg/kg bodyweight, Bleomycin 250 mg/kg + Fludilat 20 mg/kg bodyweight. The sequence of deaths was determined, and the 50% survival time was taken as criterium for the effect of the treatment. The in vitro trials showed a complete removal of the monolayer of the tumor cells from the bottom of the culture flask, in doses of 0.01-1 mg/ml medium. In the in vivo trial an increase in the 50% survival time could be achieved in all groups. The results of combined therapy of Fludilat and Bleomycin were striking. In comparison to the control animals, the treated animals showed that the occurrence of solid abdominal metastases from the Nemeth-Kellner lymphosarcoma could be almost completely prevented, especially at high doses. The Ca++-antagonistic effect, in changing the surface of the cells, is discussed as a mechanism of action.

Animals↗
PubMed1976

Irradiation treatment of inoperable squamous cell carcinomas of the oral cavity and oropharynx after partial synchronisation.

Bleomycin has proved to be an efficacious cyclus-synchronising drug in the sense that it arrests the radiosensitive G2-phase directly. In comparison with 5-Fluor-uracil, Bleomycin possesses a more effective cell-kinetics. An analytical clinical remission with the application of Bleomycin, coupled with a higher incidence of local and general side effects.

Bleomycin↗
PubMed1976

DNA histogram analysis of human hemopoietic cells.

The proliferative activity of human neoplasms may be an important determinant for therapeutic management. The advent of automated flow-through systems measuring cellular DNA content by means of fluorescence has considerably facilitated the analysis of cellular kinetics. Using a pulse cytophotometer ICP-11 (Phywe Co., Göttingen, Germany), three different fluorescent staining techniques for DNA histogram measurement on human hemopoietic cells were tested: mithramycin, ethidium bromide, and a combination of ethidium bromide and mithramycin. Employing the tritiated thymidine labeling index as reference standard for comparison with the DNA histogram-derived S-phase fractions, linear correlations were obtained using ethidium bromide alone and ethidium bromide in combination with mithramycin as staining techniques. The fluorescence intensity was increased fourfold to fivefold by the use of the two-dye combination, resulting in a substantial decrease in the coefficient of variation of DNA histograms to 1.5%-2%. This augmented histogram resolution is an important codition for detecting small-degree numeric chromosomal aberrations and discrete drug perturbation effects.

DNA↗
PubMed1976

Pulse cytophotometric analysis of cell cycle perturbation with bleomycin in vitro.

The kinetic response of a human lymphoma cell line to bleomycin has been analyzed, using an ICP-11 pulse cytophotometer. Bleomycin induced a delay of the cell-cycle traverse in G2 phase, the extent and recovery of which depended on drug concentration, exposure time, and cell cycle stage where treatment was applied. Different phase sensitivity for lethal damage (G2 phase) and kinetic response (early S phase) were documented. Recovery from G2 block did not predict for unimpaired reproductive capacity.

Bleomycin↗
PubMed1975

[The problems surrounding subtotal struma resection in hyperthyroidism with endocrinous Ophthalmopathy (author's transl)].

Observation of 39 patients who had undergone surgery for hyperthyroidism with or without endocrine ophthalmopathy between 1965 and 1972 indicate that this type of therapy involves no higher risk than do medication of radiological measures as far as the course of ophthalmic changes is concerned. Examination of the basal and the TRH-stimulated TSH concentrations i.s. argues against any primarily pituitary cause for progressive ophthalmopathy after surgery. In addition, it elucidates the almost inevitable postoperative development of preclinical hypothyroidism while the clinical condition is still euthyroid, and indicates the necessity of constant postoperative hormone substitution.

Goiter↗
PubMed1975

[First clinical results of radiotherapy following partial synchronization by bleomycin].

On the Ehrlich-ascites tumor and on the solide Ehrlich carcinoma of the mouse, bleomycin causes a large fixation in the (G2+M)-phase of the cell cycle of the tumor cells. Even in certain human solide tumors, after the application of bleomycin in a predetermined period an increase of the G2 portion of the proliferating cells can be observed. By individual control which can be peraformed rapidly and with high accuracy by impulse cytophotometry, this partial synchronisation effect can be used for radiotherapy.

Animals↗
PubMed1975

[Radiotherapy of inoperable orofacial squamous epithelial carcinomas following pharmacologically induced partial synchronization].

A therapeutical method of inoperable squamous cell carcinomas based on cell kinetics has been applied since 1969 by using 5-fluorine-uracil. Impulse cytophotometric tests did not confirm the degree of partial synchronization due to 5FU that had been assumed so far on the basis of autoradiographic techniques. The results obtained in 46 patients with inoperable malignant epithelial tumors of the maxillo-facial region that were better than those obtained with radiological therapy only, can to a certain extent be contributed to 5FU. First impulse cytophotometric findings in biopsies of animal and human tumors show that Bleomycin clearly produced partial synchronization due to a reversible stop in the radiation-sensitive G2 phase.

Aged↗