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Biomedical subjects

K Goerttler

Publications and source records attributed to K Goerttler.

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

Extended application of flow microfluorometry by means of dual laser excitation.

A dual laser beam excitation device for flow analysis of biological particles has been developed. The aid of this arrangement is to increase the range of fluorescent agents employed so far in quantitative and qualitative cytochemistry. Combining an argon ion and a helium-cadmium laser two color fluorescence measurements were performed employing propidium iodide as a DNA stain and fluorescamine which stains total protein in fixed cells. Energy transfer processes between the antibiotic and DNA specific dye mithramycin and propidium iodide both being bound to nuclear chromatin were analyzed. Utilization of energy transfer processes is generally discussed as a mean to extract information about the structure and conformation of nuclear chromatin in situ. The application of a crypton ion laser with three lines near 400 nm and a single line at 350 nm having a light output in each range of nearly one Watt gives the opportunity of utilizing DNA fluorochromes which have an excitation maximum in the deep blue region, DNA spectra are shown employing mithramycin, the benzimidazol derivative 33258 (Hoechst) and the indol compound DAPI which has a high DNA specificity combined with a great stability under UV illumination. By separating two focussed laser beams at their intersecting points with the liquid sample stream the trajectory of each flowing cell crosses the beams sequentially, which causes a solitary dual excitation of each cell. The advantages of a solitary excitation device compared with a simultaneous one is discussed.

DNA↗
PubMed1977

Monodispersal and deoxyribonucleic acid analysis of prostatic cell nuclei.

We collected prostatic glands from 50 unselected autopsies at the Pathology Institute and compared their histologic sections with cytologic preparations and with results of photometric measurements of isolated prostatic cells and isolated nuclei. The results obtained with single cell photometry and flow-through cytophotometry proved to be comparable with one another and with the results of the cytologic and histologic studies. With these methods of cytophotometry we could differentiate inflammatory conditions, microcarcinomas and frank carcinomas from normal and hyperplastic prostatic tissue. We had difficulties, however, preparing adequate suspensions of cell nuclei from chronic fibrosing prostatitis. Our results indicate that it should be possible for diagnostic purposes to combine the technique of fine needle biopsy of the prostate with that of flow-through cytophotometry and to use the combined techniques for studying diseases of other organs.

Adenocarcinoma↗
PubMed1976

Diaplacental carcinogenesis: initiation with the carcinogens dimethylbenzanthracene (DMBA) and urethane during fetal life and postnatal promotion with the phorbol ester TPA in a modified 2-stage Berenblum/Mottram experiment.

Diaplacental initiation with the carcinogens DMBA or urethane followed by topical treatment of mice of F-1 generation with the tumor promotor TPA led to the formation of benign and malignant tumors on the back skin and also in various internal organs. (This system constitutes a modified 2-stage experiment based on the early schemes of Berenblum and Mottram.) Application of either the carcinogens or the tumor promoter alone did not lead to the formation of tumors within one year. The highest skin papilloma yield was obtained with mice initiated with DMBA from the 16--19th day of fetal life. The highest total tumor yield was obtained after initiation from day 18--21st. The combination urethane/TPA also promoted the formation of tumors of the skin and other organs. The significance of this modified prenatal-postnatal initiation/promotion scheme in human pathology is discussed.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1976

Computer assistance in multiparameter flow microphotometry of mammalian cells.

Flow system technology enables the biological and medical experimenter to investigate the distribution spectra of various cellular characteristics separately or in parameter combination on the basis of ultrarapid single cell measurements. A typical rate of recognition is about 1000 to 5000 cells per second and the precision of measurements and their statistical relevance has been previously unobtainable. According to the approach of the multiparameter analysis and high data rate, computer assistance in flow system technology is given primary consideration. In this study three different kinds of software controlled modes in data acquisition are demonstrated: normal acquisition and linear accumulation of single parameters, spectra accumulation of two correlated parameters of each single cell and documentation as linear, two- or three-dimensional distribution pattern, and linear accumulation of two correlated parameters simultaneously with their actual signal-to-signal ratio. A first attempt to analyze distribution spectra was the application of the entropy of the structure routinely used in cybernetics. This function seems to be a measure for determining the degree of synchrony in an appropriate pretreated cell population. A special mathematical strategy has been applied to the linear spectra cellular DNA content, whose advantage is the quantitative extraction of the fractions concerning the various phases of the life cycle cells. The validity of this special curve fitting procedure has been proven on various experimental cell populations.

Animals↗
PubMed1976

Improved tumour yields by means of a TPA-DMBA-TPA variation of the Berenrlum-Mottram experiment on the back skin of NMRI mice. The effect of stationary hyperplasia without inflammation.

Application of the phorbol ester TPA to the back skin of NMRI mice 14 times within a period of 7 weeks causes a stationary hyperplasia, with a corresponding increase in the labelling index of the basal cells from 1% to 14%. By initiation of skin, which has been pretreated with TPA in this way, with the carcinogen DMBA, followed by continued treatment with TPA (initiation-promotion corresponding to the classical Berenblum-Mottram experiment) the tumour yield (papillomas, carcinomas) is very much higher than that obtained using the scheme of the normal Berenblum-Mottram experiment. The preliminary induction of a stationary hyperplasia with high rates of nucleic acid synthesis must be considered an important co-factor in epidermal carcinogenesis.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1975

[Cerebral granular cell tumor in the rat after intraperitoneal application of aflatoxin b1 during pregnancy (author's transl)].

On a rat, which has spontaneous died 12 months after 4 times i.p. application of aflatoxin during pregnancy, there has been found a frontal tumor barely of the size of a pepper-corn which came out from the leptomeninx. A comparison to the Abrikossoff tumor concerning the light- and electron-microscope as well as the nucleic-acid concentration is justified. The protein content of the granula of the tumor cells is higher than the values known in the granular-cell myoblastoma of man.

Aflatoxins↗
PubMed1975

The influence of non-cytotoxic concentrations of the herbicide 2,4-dichlorophenoxyacetic acid on the DNA synthesis in cultured vertebrate cells.

The influence of the herbicide 2,4-Dichlorophenoxyacetic acid on the growth of cultured chicken muscle cells was studied by observing morphological changes and by cytophotometric measurement of the DNA content of individual cells. DNA-synthesis curves were derived from the distribution of DNA values. No marked effects were observed at a concentration of 60 mug per liter. In contrast, doses of 600 mug per liter caused a loss in cell differentiation consisting of a partial lack of polar orientation, diminished formation of fibers, and an increase of the N/C ratio. The nuclear matrix of desoxyribonucleoprotein (DNP) changed to a more heteropycnotic structure. Isolated cell necroses were found after 44 hrs of exposure. When compared to the controls, the relative DNA synthesis time was found to be prolonged 1.5-fold. The number of cells in the G2 phase decreased during 44 hrs of exposure. It is concluded from these results that the dosedependent growth inhibition of 2,4-D on vertebrate cells in culture takes effect during DNA synthesis. The morphological changes of the nuclear structure suggests that 2,4-D directly affects the template activity of the DNP matrix.

2,4-Dichlorophenoxyacetic Acid↗