Disease relevance of Thymidine-14C

• A "serum-sensitive" Escherichia coli, whose DNA was pre-labeled with [14C] thymidine, released 95 to 100% of its radioactivity upon exposure to human serum for 120 min [1].
• Tumor cell recruitment in the mouse adenocarcinoma EO 771 directly demonstrated by double labeling with [3H]- and [14C] thymidine and flow cytometry [2].
• Double-labeled autoradiography with 18F-FUdR and 14C-thymidine revealed similar brain-tumor images [3].
• Incorporation of 14C-thymidine by cells infected with African swine fever virus (ASFV) occurs in the nucleus [4].
• The acute phase of infection in four cases was characterized by high spontaneous incorporation of 14C-thymidine in the cultures, unresponsiveness of lymphocytes to rubella antigen, and absence of response, or relatively low response, to PHA [5].

High impact information on Thymidine-14C

• The location of chromosomal DNA replication forks was identified in synchronously replicating E. coli cultures by pulse labeling DNA at specific times with 14C-thymidine and following incorporation of radionucleotide into genomic Not I restriction fragments [6].
• The in vitro measurement of stimulated T lymphocyte blastogenesis by the incorporation of 14C-thymidine can be shown to be an acceptable and precise measurement with highly significant variations in blastogenesis over a 24 hr period [7].
• In the cell clone used, bFGF (but not IGF, EGF or PDGF) was mitogenic in serum-free medium, increasing 14C-thymidine uptake by a factor of 10-15 within 24 hours and doubling cell proliferation [8].
• In concentrations of 5 X 10(-7)M, DHAD caused about 40% inhibition of 14C-thymidine incorporation of MIA PaCa-2 cells [9].
• The pronase-induced release of 14C-DNA from 14C-thymidine-labelled target cells was used to assess the sensitivity of the cell lines to NK activity [10].

Chemical compound and disease context of Thymidine-14C

• In this way, we obtained images showing the characteristic distribution of 14C-thymidine and D-arginine in human fibroblasts, and of 15N-adenine in organotypic cultures of human breast cancer cells [11].
• Explants of X56, an adenocarcinoma of colon, and HXG2, an amelanotic melanoma, both maintained by serial transplantation in athymic mice, were sequentially incubated in vitro with 14C-thymidine, one of several concentrations of adriamycin, and then 3H-thymidine [12].

Biological context of Thymidine-14C

• Measurements of changes in total proteins, total DNA, cell number during the experiments, and 14C-thymidine incorporation measurements indicated no significant net growth; new cell formation was below 5% in a 5-day period; therefore, amino-acid incorporation was mainly due to protein turnover [13].
• At concentrations that blocked cell division (1.2 and 2.4 per cent), halothane inhibited incorporation of 14C-thymidine and 14C-uridine into DNA and RNA, respectively, in intact cells [14].
• Cell kinetic studies on the effect of vincristine (VCR) on cells in different cell-cycle phases were carried out using single- and double-labeling methods with 3H- and 14C-thymidine [15].
• The timing of the morphological events was related to sonographically detected ovulation and to the progress of the cell cycle determined by double labelling (3H and 14C-thymidine) of newly synthesized DNA combined with autoradiographic detection [16].
• Cytophotometry of Feulgen-stained DNA in 14C-thymidine-labeled nuclei has shown that the cells that enter the mitotic cycle are mainly diploid [17].

Anatomical context of Thymidine-14C

• Because the question of cross-reactivity betweeen BUF and BN antigen was raised, lymphocytes sensitized to BN and WF donors were differentially labeled in vitro with 3H- or 14C-thymidine [18].
• A mixture of purified DNA from hormonally-stimulated control endometrium labelled by 3H-thymidine and from decidua labelled by 14C-thymidine was ultra-centrifuged to equilibrium in a Cs2 SO4-Ag gradient [19].
• The use of 14C-thymidine-labeled fibroblasts permitted later identification of the donor cells in the collagenous linings by radioautography [20].
• Furthermore, real incorporation into DNA was found in the adipocytes when incubated in vitro in a culture medium supplemented with 14C-thymidine [21].
• The incorporation of 14C-thymidine was potentiated by a factor of 10 in the presence of equal amounts of monocytes [22].

Associations of Thymidine-14C with other chemical compounds

• Ventral and dorsolateral prostatic lobes (VP and DLP), obtained from mice at different ages and at different intervals after castration or treatment of castrated males with testosterone propionate (TP), were microdissected into two-dimensional arrays and incubated in vitro with 14C-thymidine [23].
• The findings, which were obtained with the aid of the liquid scintillation counter and partly by means of 14C-thymidine-marked autoradiographies shows clearly that Adriamycin causes the strongest incorporation inhibition [24].
• On the other hand, all three androgen derivatives, which had appeared inactive in vivo, had similar effects in vitro (as had active testosterone) as demonstrated by inhibition of Concanavalin A-induced lymphocyte activation expressed by 14C thymidine incorporation and inhibition of cell agglutination [25].
• After 3 and 6 days' culture with Kveim antigen (1, 10, 100 micrograms/ml), PPD tuberculin (2.5 micrograms/ml) and Con A (10, 20, 40 micrograms/ml) stimulation was measured as incorporation of 14C-thymidine into DNA [26].
• A sensitive alkali-unwinding assay was used to measure DNA strand breakage in Chinese hamster V79 cells caused by low-level incorporation of methyl-labelled [3H] and [14C] thymidine, and to estimate the effective dose per disintegration relative to low doses of gamma-irradiation [27].

Gene context of Thymidine-14C

• Human lymphocytes, stimulated by PHA, and exposed to increasing Na2HAsO4 concentrations, show an identical incorporation rate for 14C thymidine and 14C-TTP into the DNA [28].
• Both the uptake of 14C-thymidine and 65Zn by the cells was significantly suppressed by detachment from the extracellular matrix, suggesting that cellular zinc uptake is suppressed by growth arrest [29].
• Incorporation of 14C-thymidine by cultures of erythrocytes from rheumatoid arthritis patients and normal subjects, suggesting the presence of an L-form [30].
• The latter event was evidenced by a suppressed 14C-thymidine incorporation into thymocytes DNA in vitro, decreased thymidine kinase activity, intracellular dTTP and depletion of dCTP pools [31].
• DNA and non-histone chromosomal proteins (NHCP) of meristematic cells of maize primary roots were double labelled in vivo with [3H]- or [14C] thymidine and [14C]- or [3H]-tryptophan respectively [32].

Analytical, diagnostic and therapeutic context of Thymidine-14C

• The incorporation of 14C-thymidine into DNA was measured at 4-hr intervals from 16 to 32 hr after partial hepatectomy in groups of rats [33].
• A rapid anticancer drug screening assay by [14C] thymidine uptake in cultured human cancer cells [34].
• Double labeling autoradiography. Cell kinetic studies with 3H- and 14C-thymidine [35].
• Antigen-induced lymphocyte proliferation was studied by quantitation of 14C-thymidine uptake in cell cultures [36].
• The morphology and kinetics of the cytotoxicity reaction were studied by scanning electron microscopy and compared with release of radioactivity from 14C-thymidine-labelled target cells [37].

References