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C Tse

Publications and source records attributed to C Tse.

23 records · Page 2Linked to original sources
PubMed1979

Structure of polyadenylic acid in the ribonucleic acid of Saccharomyces cerevisiae.

Investigations of the structure of polyadenylic acid [poly(A)] in yeast have shown that there are two classes of poly(A) distinguished by size and kinetics of synthesis. Each class is found directly on the 3' end of messenger RNA. One class contains poly(A) molecules ranging from 60 to less than 20 nucleotides long. The longest molecules in this poly(A) class are the first to become labeled when cells are exposed to [3H]adenine. Label then appears in progressively smaller molecules. The second class of poly(A) is about 20 nucleotides long. The length homogeneity of this class and the presence in nuclear DNA of many copies of a polythymidylate sequence which is the same length suggests that this poly(A) is synthesized by transcription from DNA.

Adenosine↗
PubMedDate not supplied

[RNA isolation and purification methods].

Recent advances in human, bacterial and viral genome projects and the development of quantitative real-time reverse transcription-polymerase chain reaction methods offer the possibility of analysing a large number of gene transcripts. These molecular developments represent an important advancein the field of genetics, cancer, virology, bacteriology and hematology. A limiting step remains the isolation of high quality mRNA purified from biological samples. This review describes the different methods used to isolate mRNA from biological samples and to verify RNA integrity and gives precise details about RNA storage conditions.

Blotting, Northern↗
PubMedDate not supplied

[Real time PCR methodology for quantification of nucleic acids].

The polymerase chain reaction (PCR) has become an essential tool for molecular biologists and its introduction into nucleic acids detection systems has revolutionized the quantitative analysis of DNA and RNA. The technique has rapidly evolved over the last few years and the growing interest in quantitative applications of the PCR has favoured the development of real-time quantitative PCR. In this paper, we review, after presentation of the theorical aspects of PCR, the basic principles of real-time PCR with the introduction of the concept of threshold cycle. More precisely, we describe the novel assay formats that greatly simplify the protocols used for the detection of specific nucleic acids. We focus on the actual four technologies that enable sequence detection in a closed tube and that are SYBR Green I, TaqMan probes, Hybridization probes and Molecular Beacon probes. We then discuss the different quantification strategies in real time PCR and compare the competiting instruments on the market. The most important real-time PCR applications in clinical biology are also described.

Clinical Protocols↗
PubMedDate not supplied

[Current aspects of the evaluation of ERBB2 activation in breast cancer. Therapeutic perspectives].

The ERBB2 (HER-2/neu) protooncogene encodes a transmembrane protein with an intracellular tyrosine kinase activity. It is principally activated by gene amplification and its product, the erbB2 protein, becomes oncogenic when overexpressed. Quantitative PCR is both a simple and reliable method for the evaluation of ERBB2 activation, whereas immunoenzymatic methods allow quantitative determination of erbB2 protein in tissue and sera. ERBB2 amplification and/or surexpression is actually recognized as a prognostic factor in breast cancer and would be predictive in the therapeutic response. It might lead also to new therapeutic modalities using specific targeted drugs.

Biomarkers, Tumor↗