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K Goerttler

Publications and source records attributed to K Goerttler.

At least 73 records · Page 4Linked to original sources
PubMed1980

Synthesis in vitro of keratin polypeptides directed by mRNA isolated from newborn and adult mouse epidermis.

A method is described which allows the isolation of undegraded total cellular RNA from living epidermis in a one-step procedure. Epidermal tissue is homogenized in 4 M guanidinium thiocyanate/2% sarkosyl buffer and centrifuged through a 5.7 M CsCl cushion. Under appropriate density conditions in the homogenate, large amounts of RNA are sedimented free of DNA and protein to the bottom of the tubes. A prerequisite for the applicability of this method is the preparation of pure epidermis under conditions which efficiently inactivate endogenous RNases. Oligo(dT) affinity chromatography of total RNA yields 3-4% of polyadenylated RNA. Translation of poly(A)-rich fractions from both newborn and adult mouse epidermis in a cell-free reticulocyte system leads to the synthesis of proteins with electrophoretic mobilities identical to those of native keratin polypeptides of the corresponding tissue. Similar to native keratin polypeptides, these proteins are highly insoluble and can selectively be enriched by high-salt extraction of the translation assays. The CNBr cleavage pattern of these purified proteins is identical to that of native keratins. There is no evidence for the synthesis of precursors of these proteins.

Aging↗
PubMed1979

Microflowfluorometric evaluation of homeostasis in cultured epidermal cells.

In isolating and culturing in vitro populations of basal cells from adult guinea pig skin, it has been possible to show that these cells are sensitive to both G1 and G2 inhibitions. Only a small fraction (10 percent or less) of the G1 blocked cell population would be governed by G1 inhibitory messages released by suprabasal, maturing keratinocytes. As regards the G2 block in vitro experiments confirm that basal cells produce a G2 blocker to which about 9 per cent or less are susceptible. In conclusion basal cells in culture are sensitive to homeostatic regulation as in vivo.

Animals↗
PubMed1979

Quantitative cytology of the positive region in flow sorted vaginal smears.

Fifty-one gynecologic specimens were collected from three women's hospitals and mailed in a prefixed status to our laboratory. The specimens were classified into a negative, a suspicious, a postradiation, and a positive group. After single cell dispersion the samples were stained for DNA and protein, analyzed, and sorted in the dual laser equipped Heidelberg flow analyzer sorter (HEIFAS). Particles with elevated DNA values (beyond 3.5 ploidy) and with intermediate protein values were sorted as the positive fraction directly on microscopic slides. After restaining according to Papanicolaou, they were re-evaluated cytologically and identified as tumor cells, dysplastic cells and false alarms. The latter consist of doublets and aggregates of more than two cells, binucleated cells, sperm aggregates and epithelial cells contaminated with bacteria. The different groups showed significant differences regarding the total rate of aggregates to single cells. In general, false alarms were very frequent in the positive region and impeded the statistical classification of the sample. The reduction of false alarms is a prerequisite for prescreening with flow instrumentation.

Cervix Uteri↗
PubMed1979

The Heidelberg flow analyzer and sorter (HEIFAS) approach on the prescreening of uterine cancer.

A dual laser flow system has been proved and used with a novel staining method for simultaneous quantitative DNA and protein analysis. A diamidinophenylindole compound (DAPI) for DNA has been employed in combination with sulforhodamine (SR 101) for protein. With this dye mixture various cell types of the cervical smear could be identified. Despite some overlapping, clusters of leukocytes, endocervicals, (para)basals, intermediates, superficials and dys/neoplastic cells together with artificial events could be discriminated. Up to now the problem of negative cells which create positive signals (false alarms) in the dys/neoplastic region could not be sufficiently solved.

Cervix Uteri↗
PubMed1979

Systemic two-stage carcinogenesis in the epithelium of the forestomach of mice using 7,12-dimethylbenz(a)anthracene as initiator and the phorbol ester 12-O-tetradecanoylphorbol-13-acetate as promoter.

In a modified two-stage carcinogenesis experiment, the effectiveness of the initiator 7,12-dimethylbenz(a)anthracene (DMBA) and the tumor-promoting phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA) in the epithelium of the forestomach of the mouse has been investigated. Fifty mice were treated intragastrically with a single dose of DMBA (50 mg/kg body weight), followed by repeated intragastric administration of TPA (10 mg/kg body weight) over a period of 35 weeks. In comparison with the corresponding control groups (no treatment, DMBA initiation only, and TPA treatment only), the initiated and promoted group clearly showed the highest tumor incidence in the target organ (45 tumor-bearing animals of 50 animals). No tumors of the forestomach were found in the untreated control group and the TPA-treated group, whereas in the DMBA-initiated group, ten animals had developed tumors of the forestomach. In addition to the mouse skin model for two-stage carcinogenesis, the mouse forestomach appears to respond to DMBA initiation-TPA promotion. This organ provides an additional tissue with which to investigate tumor promotion and further to ascertain specific parameters of the promotion step.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1978

High incidence of spontaneous transplantable tumours in BDX rats.

Untreated male and female BDX rats were observed over a period of 30 months for spontaneous tumours of a size suitable for transplantation. At the age of 13-30 months 60/97 animals developed tumours, 53 of which were considered as malignant, and 7 as benign tumours. The spectrum of malignant tumours included sarcomas of connective tissue and bone, skin carcinomas, tumours of the lung, the gastrointestinal tract, the genito-urinary tract, the mammary glands, the testis, the adrenal glands and also sarcomas of the neural system and malignancies of the lymphoreticular system. Out of 41 tumours implanted s.c., 34 of them could be passaged further. The primary latent period varied between 1 and 12 months.

Animals↗
PubMed1978

Transmaternal modification of the Berenblum/Mottram experiment in mice.

The classical 2-stage carcinogenesis experiment has been modified in that the carcinogen DMBA was applied to pregnant mother animals at different dose levels and different time intervals during pregnancy. Promotion with the phorbol ester TPA was performed as usual by application of the promoter on the back skin of mice of the F-1 generation. It can be shown that it is possible to initiate fetal epidermal cells by transmaternal route and to promote them to produce visible skin tumors post natum. Tumor promotion by TPA is not restricted to the epidermis, since a broad spectrum of tumors of internal organs can be demonstrated in the initiated and promoted animals. This more general promoting activity of TPA--which implies its absorption and distribution throughout the whole body--has not yet been described. In addition, especially sensitive phases during fetal life with regard to initiation of cells by the carcinogen can be demonstrated. These phases comprise the last third of pregnancy and coincide with a high proliferative activity and the onset of differentiation of the fetal epidermis. The results emphasize the important role of prenatal carcinogenesis and demonstrate the increased risk also to the human organism by either prenatal initiation or postnatal promotion.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1978

On the existence of 'arrested G2 cells' in mouse epidermis.

It has been postulated that mouse epidermis contains two populations of resting cells, one of which is blocked at the G1-S boundary and the other between G2 and mitosis. The 'arrested G2 cells' were estimated, by the labelled mitosis method, to comprise 5-10% of the epidermal population and presumed to function as a 'reserve pool' which could be activated by wounding. A comprehensive search has now been carried out for arrested G2 cells in mouse epidermis using the direct methods of single cell and flow through cytophotometry. No evidence was obtained which supports the existence of such a cell compartment. Suitable control experiments were carried out to ensure that G2 cells were not lost during the isolation of epidermal nuclei.

Aging↗
PubMed1977

Epidermal intercellular relationships during carcinogenesis and cocarcinogenesis as revealed by scanning electron microscopy.

Investigations with the scanning electron microscope were carried out on the skin of 80 NMRI mice after treating them with small doses of the carcinogenic substance DMBA and the cocarcinogenic agent TPA, respectively. The results were correlated with histologic, transmission electron microscope and autoradiographic observations. The epidermis of TPA-treated animals was markedly hyperplastic with an orderly arrangement of cell layers. Autoradiographically only the basal cells were heavily labelled. With the scanning and transmission electron microscope a reduced number of intercellular connections and dilatation of the intercellular spaces could be detected. After treatment with DMBA the epidermis was only moderately hyperplastic but severely dysplastic with 3H-thymidine-labelled cells in the upper layers. The most characteristic findings were the loss of the intercellular connections, especially the lateral ones, and a pronounced dilatation of the intercellular spaces. The results obtained with the scanning electron microscope were quantified using morphometrical methods.

9,10-Dimethyl-1,2-benzanthracene↗