Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 24 (1973), S. 287-303 
    ISSN: 1432-0533
    Keywords: S-100 Protein ; Experimental Neurogenic Tumors ; Nitrosourea ; Rat ; Complement Fixation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary S-100 protein, a soluble protein restricted to the nervous system, was measured by complement fixation in 51 neurogenic and non-neurogenic tumors produced by either methylnitrosourea or ethylnitrosourea in three different strains of rats. Nineteen of the 51 neurogenic tumors were neoplasms of the central nervous system (18 of the brain, 1 of the spinal cord). They were diagnosed morphologically as 5 mixed gliomas, 4 anaplastic gliomas, 4 glioependymomas, 1 ependymoma, 3 gliosarcomas, and 2 unclassified tumors. With the exception of one anaplastic glioma and one gliosarcoma, all other central nervous system tumors contained S-100 protein, ranging from 0.005–0.13% of the total 35000 g supernatant protein. S-100 protein was also demonstrated in 21 of the 22 tumors of the peripheral nervous system, originating from the trigeminal nerves, the spinal roots, and from peripheral nerves. The average S-100 protein content of these tumors was 0.2% (range 0.02–1.6%). A possible correlation between S-100 protein content and tumor differentiation must be evaluated. S-100 protein was detected in only one of 10 neoplasms morphologically classified as non-neurogenic (7 sarcomas, 2 carcinomas, and 1 hemangioendothelioma). On the basis of its S-100 protein content, one tumor was reclassified as a neurosarcoma. The sensitivity and the high degree of specificity of the S-100 protein assay makes it a useful biochemical tool for the identification of neurogenic tumors. The presence of S-100 protein must be considered as a definitive indication for neural cell participation in neoplastic growth.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The rate of RNA synthesis in synchronously growing HeLa S3 cells was determined as a function of position in the cell generation cycle. Measurements throughout the cycle of both the rate of incorporation of radioactively-labeled uridine and of the total amount of RNA indicate that (1) the rate of RNA synthesis is constant (or increases only slightly) during G1, approximately doubles during the first half of S, and then remains constant during the remainder of S and G2, and (2) cells attain the average G1 rate of RNA synthesis very early in G1, and maintain the average G2 rate until mitosis.If the initiation of DNA synthesis is blocked, the acceleration of RNA synthesis is markedly reduced or eliminated. Further experiments in which DNA synthesis was inhibited at different times in S, or to varying degrees from the beginning of S, suggest that the extent to which RNA synthesis is accelerated depends on the amount of DNA duplicated. These data also indicate that duplication of the first half, and in particular the first few per cent, of the DNA complement results in a disproportionate acceleration of RNA synthesis.The possibility that fluctuations in the sizes of precursor pools may lead to misinterpretation of labeled-uridine incorporation data was examined. Experiments indicate that in this system pool fluctuations do not cause invalid measures of RNA synthesis.It is concluded that RNA synthesis occurs throughout interphase, but undergoes a two-fold increase in rate which is dependent on the duplication of DNA.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 75 (1970), S. 329-339 
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The synthesis of a protein unique to the nervous system, the “S100-protein,” has been studied in a clonal line of rat glial cells. It has been shown that these cells do not begin to accumulate “S100-protein” until the cultures enter a phase of density-dependent inhibition of cell proliferation. Further experiments indicate that the regulation of “S100-protein” accumulation resides at least in part in an interaction involving the cell surface.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 78 (1971), S. 145-151 
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Adaptation of monolayer cultures of a clonal line of rat glial cells to suspension culture resulted in the nearly complete loss of certain surface antigens. This change in surface antigenicity was paralleled by the loss of the ability of the cells to accumulate in vitro a protein specific to the nervous system (“S100-protein”). In contrast, when glial cells were co-cultivated in monolayer culture with another cell line apparently lacking these surface antigens, the number of these antigens was markedly increased. The possibility of a causal relationship between the changes in the surface antigenicity and the expression of differentiated function is considered.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The rates of synthesis of various species of RNA were examined in synchronously growing HeLa cells as a function of stage in the cell generation cycle. The synthesis of each RNA species examined occurs throughout interphase, but undergoes a two-fold increase in rate during early S which is dependent on the duplication of DNA; blocking the initiation of DNA synthesis also blocks the acceleration of RNA synthesis. To explain the data, a model is discussed in which the acceleration of RNA synthesis during early S is regulated by the number of active cistrons present; thus, as the genome is duplicated, more template is available for transcription, and the rate of RNA synthesis increases. Some implications of the model, and experimental evidence bearing on them, are also discussed.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...