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S Schiemann

Publications and source records attributed to S Schiemann.

14 recordsLinked to original sources
PubMed1998

Molecular analysis of two mammary carcinoma cell lines at the transcriptional level as a model system for progression of breast cancer.

As a model system for the identification of genes involved in the progression of human breast cancer, differential gene expression in cell lines MCF-7 and MCF-7ADR was investigated. The latter cell line is derived from the former. Cell line MCF-7 is estrogen receptor-positive, vimentin-negative and uninvasive in the Matrigel outgrowth assay and in the nude mouse, while MCF-7ADR is estrogen receptor-negative, hormone-resistant, vimentin-positive, invasive in the Matrigel outgrowth assay and in the nude mouse and resistant to adriamycin due to overexpression of glycoprotein gp170. We have shown that tumor progression in this model system is mediated by transcriptional regulation of mitochondria-related genes, proteases, transmembrane receptors and cell cycle-related gene proteins. Among the genes differentially regulated at the transcriptional level in the cell lines MCF-7 and MCF-7ADR are a new mitochondrial transcript, mitochondrial creatine kinase, matrix metalloproteinase-1, stromelysin-3, urokinase and its receptor, tissue factor, E-cadherin, epidermal growth factor receptor, transmembrane proteins Mat-8 and progression associated protein (PAP), cyclin E, cyclin-dependent kinase-2 and cell cycle inhibitory proteins p16, p21 and p27.

Animals↗
PubMed1994

Adenosine and homocysteine together enhance TNF-mediated cytotoxicity but do not alter activation of nuclear factor-kappa B in L929 cells.

This paper shows that a combination of adenosine and homocysteine potentiates TNF-alpha-mediated cytotoxicity, but does not modulate activation of NF-kappa B transcription factor controlling the expression of various TNF-alpha-inducible genes. Adenosine and homocysteine at concentrations (1 mM each) that enhance TNF-alpha-induced cytotoxicity accumulate S-adenosyl-L-homocysteine (AdoHcy), a potent inhibitor of S-adenosyl-L-methionine-dependent methylation reactions. In addition, preloading L929 cells with AdoHcy resulted in enhanced responses to TNF-alpha, suggesting that AdoHcy potentiates TNF-alpha-induced cytotoxicity. Moreover, the combination of adenosine and homocysteine changed the dependency of the TNF-alpha-mediated cytolysis on reactive oxygen intermediates. In the absence of adenosine and homocysteine TNF-alpha-mediated cytotoxicity was inhibited by antioxidants such as butylated hydroxyanisole and pyrrolidine dithiocarbamate. In the presence of adenosine and homocysteine, however, TNF-alpha-mediated cytotoxicity is not inhibited by these antioxidants. A L929 subclone, defective in the respiratory chain, resisted the cytotoxic action of TNF-alpha, but was rendered TNF-alpha sensitive in the presence of adenosine and homocysteine. Unlike TNF-alpha-mediated cytotoxicity, the TNF-alpha-induced activation of NF-kappa B was inhibited by antioxidants regardless whether adenosine and homocysteine were present or absent in the culture medium. In conclusion, a combination of adenosine and homocysteine selectively modulates TNF-alpha-mediated cytotoxicity without changing the TNF-alpha-induced activation of NF-kappa B. Our results could facilitate the development of strategies that permit dissection of cytotoxic and gene-activating pathways.

Adenosine↗
PubMed1978

[Experiences gained from the establishment of a complex physical therapy program for the management of female urinary incontinence].

Reported in this paper are preliminary experiences so far obtained from a complex physiotherapeutic programme for conservative and pre-operative treatment of functional urinary incontinence in women. Included in this pilot study were 82 patients of whom 23 (28 per cent) were continent on termination of the therapy, while another 38 (46 per cent) had improved to an extent where they abandoned their original intention to undergo surgery for incontinence. Complex physiotherapy may add favourably to the spectrum of possible therapeutic approaches, provided its proper and differentiated coordination with the generally known surgical approaches.

Electric Stimulation Therapy↗
PubMed1976

[Investigations on the mechanism of the activity of urea upon the epidermis (author's transl)].

As a reaction of the epidermis subsequent upon contact with urea, a thinning is ascertainable 5 days later, for which corresponding enzymological and autoradiographical findings cause to presume the DNA being the working point. Further information about the mechanism of this reaction was obtained first by short time tests, whence by means of 3H thymidine autoradiography not later than the second day after contact with urea a decreased number of cells synthesizing DNA in the stratum basale were to be secured. These findings obtained using the model of the guinea-pig's ear are also ascertainable in the human skin, an unspecified effect, also to be released by other non-electrolytes, having been excluded by controls of glucose replacing urea. The quick invasion of urea into the epidermis, deducible from the short time tests, was proved by 14C traced urea, ascertainable not later than 15 min after its contact with the skin amongst the blood - even if in little activity. Hence, the urea enters into the cutis speedily, releasing there a disturbance in the process of the epidermal proliferation, which conducts in the sequel to an epidermal thinning.

Animals↗
PubMedDate not supplied

New genes potentially involved in breast cancer metastasis.

Identification of new genes involved in the pathogenesis of breast cancer opens new avenues for improved diagnostic markers and new molecular targets for improved treatment of this malignancy. In the following we review genes with proved involvement in invasion and metastasis of breast cancer as well as genes which exhibit an expression pattern that correlates with invasion and metastasis.

Amino Acid Sequence↗
PubMedDate not supplied

[The social function of the hospital].

Issuing from the statements to the change of the social institution hospital in the course of history the experiment is undertaken to outline the social function of the hospital on the conditions of the developed socialist society.

Aged↗
PubMedDate not supplied

[Determination of biologic aging within the scope of the Halberstadt Gerontologic Study. 4. Some theoretical and methodologic considerations on the future development of assessment tests].

With regard to the test-set developed by RIES and co-workers for the purpose of determination of the biological age the authors again refer to the necessity of a corresponding catalogue of methods with a view to the measurement of work capacity and of health condition at the age. Theoretic problems concerning the examination of functional parameters are discussed. Proposals to a theory-related continued development of work capacity and of health condition are presented, especially to master common problems of daily life at the age.

Activities of Daily Living↗
PubMedDate not supplied

[Determination of biologic aging within the scope of the Halberstadt gerontologic study. 1. Preliminary remarks, on Partial Index I (prevailing physical area].

Within the bounds of the Halberstadt study it is undertaken, to register the health condition and the work capacity of elderly people. To this purpose the Leipzig test set for the determination of biological age examination and its applicability is discussed. The experience shows, that this test set with the discussed task specific modifications can be applied. Character and extent of the necessary modifications, which result for the partial index I (prevalent physical range) are presented in this first information.

Aged↗
PubMedDate not supplied

[Determination of biologic aging within the scope of the Halberstadt gerontologic study. 3. Partial Index III (prevailing social area)].

In the third information on the application of the Leipzig test set for the determination of biological age within the bounds of the Halberstadt study the partial index III (prevalent social range) is submitted to critical consideration. The Leningrad Assessment Scale is compared with the Halberstadt questionnaire programme.

Activities of Daily Living↗
PubMedDate not supplied

Differential gene expression in human mammary carcinoma cells: identification of a new member of a receptor family.

Differential gene expression in mammary carcinoma cell lines MCF-7 and MCF-7ADR was investigated by Differential Display Technique. These two cell lines represent a model system for progression of mammary carcinoma: MCF-7 is estradiol-dependent for growth, estrogen-receptor positive, tamoxifen responsive, vimentin negative, Adriamycin sensitive and not invasive in vitro or in vivo while MCF-7ADR is estradiol-independent for growth, estrogen-receptor negative, tamoxifen resistant, vimentin positive, Adriamycin resistant and invasive in vitro and in vivo. Here we describe the identification of a new receptor expressed exclusively in MCF-7ADR. The receptor covers 157 amino acids with a predicted topology of four transmembrane and two extracellular domains. Additional members of the gene family are: peripheral membrane protein PMP22, epithelial membrane protein EMP-1 and squamous cell differentiation marker CL-20.

Amino Acid Sequence↗
PubMedDate not supplied

Assignment of the human progression associated protein (PAP) to chromosome 12p12.3.

Analysis of mammary carcinoma cell lines MCF-7 and MCF-7ADR by differential display resulted in the identification of a new putative transmembrane protein, PAP (Progression Associated Protein). Cell lines MCF-7 and MCF-7ADR represent a model system for the identification of genes involved in the clinical progression of human breast cancer. According to the functions assigned to some members of its family, PAP might be involved in cell cycle regulation and cell-cell interactions. Here we describe the chromosomal localization of the PAP gene by the use of fluorescence in situ hybridization (FISH) with two different genomic DNA probes, derived from the 3'-untranslated and the 5'-translated region of the PAP cDNA sequence. The results of the chromosomal localization experiments indicate that the PAP gene is located on human chromosome 12p12.3.

Breast Neoplasms↗