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H Krug

Publications and source records attributed to H Krug.

At least 91 records · Page 5Linked to original sources
PubMed1976

[Impulse cytophotometric investigations on tumour material (author's transl)].

By impulse cytophotometry (ICP) we can get the distribution of the frequency of cell nuclei as a function of the fluorescence intensity. The interpretation of the curves is only possible on the basis of histophysical and histochemical features. The following problems are discussed: specificity of staining with ethidium bromide, pretreatment, detritus, comparison with other independent methods. The second peak of the karyogram consists of G2-cells and, in polyploidy of tetraploid cells. This peak is often high in cell suspensions of malignant tumours; sometimes we found polyploidy up to 16c. The stem line concept is discussed. The ICP is a valuable aid in exfoliative cytology, but no screening method.

Cell Nucleus↗
PubMed1976

[Pulse cytophotometric and cytologic repeated examinations of cervical secretions as compared with histologic findings (author's transl)].

1625 cervical smears from 397 women were investigated in special cytological consultations. On the same material 693 impulse cytophotometric (ICP) measurements were made, stained with ethidium bromide after pepsination. In 207 patients the diagnosis was certain by histology. The mean height of the 4c-peak (in 0/00 of the 2c-peak) raises with the Papanicolaou grading from 38,2 in Pap. I up to 128,8 in Pap. V. In histological confirmed cases in dysplasia the mean 4c-height was 79,5 and in carcinoma 102.2. If only one ICP investigation was turned to account there are some disagreements between the ICP value and the diagnosis finally resulting from the clinical and cytological course. The differences are considerably diminished by repeated ICP investigations. Therefore ICP measurements are a valuable aid in interpreting cytodiagnostic problems. They often facilitate the choice of further diagnostic and therapeutic procedures.

Cervix Uteri↗
PubMed1976

[A mathematical model concerning the DNA-karyogram in connection with the cell cycle. I. Communication. The derivation of the DNA frequency distribution from the duration of the single phases of cell cycle (author's transl)].

Stimulated by our own experience on flow microfluorometry we establish a mathematical model concerning the connection between the duration of the single phases of cell cycle and frequency distribution of cell nuclei as a function of their DNA content. For the establishment of the equations we need some simplified suppositions. We interprete the distribution curve (DNA karyogram) as 3 superimposing portions: 1. A Gaussian distribution of G1-phase cells at the first or 2c-peak. 2. A Gaussian distribution of G2 + M phase cells at the second or 4c-peak (twofold DNA content). 3. Nuclei from the S-phase with DNA content between the mean values of the two Gaussian curves. Our model has the following pecularities: 1. The establishment of the equation for the curve and therefore the addition of the partial curves is done in a logarithmical (log-normal) system. Here we can assume the same standard deviation both for the first and the second peak. 2. The superimposing of the S-phase acts on the whole curve and not only between the mean values of the Gaussian curves. Here the integral of the Gaussian distribution is employed for the equation. The equations are elaborated for the whole curve with the periods of the single phases as parameter, for the positions of the maxima and the minimum and for the quotient of the arguments of the maxima ("rhythm of reduplication") as a function of the duration of the single phases. Some examples are given and drawn in diagrams. They demonstrate the shape of the DNA karyogram and the rhythm of reduplication as funtions of the duration of the single phases of the cell cycle. The transformation in the linear system distorts the shape of the curve up to the disappearance of the second peak. The results from the model are the base for the interpretation of DNA karyograms, originating for instance from cytophotometry, mainly from flow microfluorometry. With the model we can estimate a change in direction and quantity of the curves altered by different phases of the cell cycle.

Cell Division↗
PubMed1976

[The characterisation of malignant ovarian tumors by impulse cytophotometry (author's transl)].

31 malignant adnexal tumors were investigated by impulse cytophotometry. From the DNS distribution curves we interpreted the positions and the height of the peaks in order to get informations about ploidy and proliferation pattern. 45.2% were classified into the diploid, 29.0% into the polyploid and 12.9% into the tetraploid group. 12.9% were aneuploid. Comparing our results with chromosome analyses in the literature we found more tetraploid tumors in our material. For our polyploid curves we assume, that many of the cells in the 8c-peak remain in the corresponding G2'-Phase, not undergoing mitosis.

Adult↗
PubMed1975

[Impulse cytophotometric investigations on melanoblastoma (author's transl)].

We investigated 24 patients with melanotic tumours (under them 22 malignant melanoms). The tumour material (31 x by biopsy, 2 x by autopsy) was homogenized and stained with Ethidium bromide after pepsination. The distribution of the DNA content of the tumour cell nuclei was measured by impulse cytophotometry. The criterion for the curves was the height of the 4-c-peak in percentage of the diploid peak. Our material was divided in 3 groups: I. Without metastases. II. Metastases, slowly progressive. III. Metastases, rapidly progressive. Between the groups there were significant differences: the higher the 4-c-peak, the greater the malignancy. In the group III we mostly had tetraploid populations with the maximal peak at 4-c. The course of the disease (as seen by metastasis, effect of chemotherapy, growing in cell culture) runs parallel to the findings of impulse cytophotometry. In one case of melanosis praeblastomatosa circumscripta Dubreuilh we found a pure diploid cell population without peaks at 4-c. For prognosis (not for diagnosis) the impulse cytophotometric investigation of malignant melanoma is more suitable than the histology. In the discussion we expose the connections between proliferation and DNS distribution of cell nuclei in a tetraploid population. The terminology of cell cycle phases is extended to tetraploid populations with new terms (G', S'). In some cases we found stem lines. As shown by repeated impulse cytophotometric investigations a changing of stem lines in the DNA distribution curve is possible (change from hyperdiploid to tetraploid). The impulse cytophotometry is suitable for such investigations on melanomas.

Cell Nucleus↗