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K Lipp

Publications and source records attributed to K Lipp.

11 recordsLinked to original sources
PubMed1980

Dexamethasone binding to chromatin, inhibition of in vitro RNA synthesis, and therapeutic effect on human lymphosarcoma.

A very high degree of specific dexamethasone binding to chromatin and a marked in vitro inhibition of RNA-synthesizing capacity of purified lymphoma cell nuclei was found to correlate closely with the very strong cytolethal effect of glucocorticoids on lymphoma cells (in this case neither B- nor T-cells) of a young patient, whose condition rapidly and unexpectedly deteriorated after a total dose fo 90 mg of Prednisone given during a two day period; and in spite of prophylactic antihyperuricaemia treatment, the patient subsequently died. In this case the amount of glucocorticoid bound specifically by lymphoma chromatin was about 400% larger than is normally found in chromatin isolated from normal human thymus cells in persons on this age. The in vitro inhibition of RNA-Synthesizing activity measured with the aggregate enzyme and with isolated nuclei from lymphoma cell-nuclei by dexamethasone correlates closely to the specific dexamethasone binding capacity of chromatin. Thus a better prediction of the therapeutic effect of such lymphosarcoma cells to glucocorticoid may be possible.

Child↗
PubMed1977

RNA synthesizing activities and glucocorticoid binding capacities in thymus cells during rat development.

This investigation was designed to study specific glucocorticoid binding to cytoplasmic fraction and nuclei of thymus cells during rat development and to find out whether these data can be correlated to changes of RNA synthesizing activity of nuclei and cytoplasm. The dexamethasone binding capacity of cytoplasm rose rapidly in rats weighing up to 125 g and decreased significantly in animals weighing more than 160 g. Hormone binding to nuclei revealed similar but less pronounced changes. RNA synthesizing activity of nuclei measured by [3H]uridine incorporation in vitro decreased from 57 +/- 4.6 dpm/microng DNA in young to 23 +/- 2.2 dpm/microng DNA in adult rats. RNA synthesizing activity of the cytoplasmic fraction fell 21.6% and that of purified polymerase IIIB fell 27.8% during development. Inhibition of RNA synthesis by dexamethasone applied in vivo and in vitro showed age-dependent differences. The RNA synthesizing capacity of nuclei was inhibited up to 39% in animals weighing 130 g and only 9% in aging rats. Similar changes were observed by incubation of intact thymocytes with and without hormone. The observed inhibitory effect of dexamethasone on RNA synthesis is well correlated to changes of cytoplasmic hormone receptor capacities during development.

Age Factors↗
PubMed1976

[Template activity of chromatin and DNA-dependent RNA polymerase III during postnatal development (author's transl)].

The template-activity of chromatin isolated from liver nuclei of developing rats increases sharply at birth and decreases remarkable until the 10th day. Between the 10th and the 40th day a slow increase was shown in template activity of chromatin tested with purified E.-coli RNA-polymerase (EC 2.7.7.6). We correlated these findings with changes of RNA-polymerase III-activity in rat liver during development.

Age Factors↗