Uncertainty of a hybrid surface temperature sensor for silicon wafers and comparison with an embedded thermocouple.

We have developed a user-friendly hybrid surface temperature sensor. The uncertainties of temperature readings associated with this sensor and a thermocouple embedded in a silicon wafer are compared. The expanded uncertainties (k=2) of the hybrid temperature sensor and the embedded thermocouple are 2.

Alkyl-fluorinated thymidine derivatives for imaging cell proliferation II. Synthesis and evaluation of N3-(2-[18F]fluoroethyl)-thymidine.

We prepared N(3)-(2-[(18)F]fluoroethyl)-thymidine ([(18)F]NFT202) and examined its potential as a positron emission tomography (PET) ligand for imaging cellular proliferation. [(18)F]NFT202 was synthesized from 3',5'-di-O-toluoyl-N(3)-(2-p-toluenesulfoxyethyl)-thymidine in a two-step reaction. N(3)-(2-fluoroethyl)-[2-(14)C]thymidine ([(14)C]NFT202) was also synthesized from [2-(14)C]thymidine in a one-step reaction.

Alkyl-fluorinated thymidine derivatives for imaging cell proliferation I. The in vitro evaluation of some alkyl-fluorinated thymidine derivatives.

Derivatives of 2'-deoxyuridine that contain fluoroalkyl groups at the C5 position and derivatives of thymidine that contain fluoroalkyl groups at the N3 position were synthesized and examined in three in vitro assays designed to evaluate their potential as radiopharmaceuticals for imaging cellular proliferation. Three of the former nucleosides and five of the latter were synthesized. The three assays were as follows: (a) phosphoryl transfer assay, which showed that all three of the former nucleosides and four of the latter ones were phosphorylated by recombinant human thymidine kinase 1 (TK1) and that N(3)-(2-fluoroethyl)-thymidine (NFT202) was the most potent substrate of the eight nucleosides studied; (b) transport assay, which indicated that all eight nucleosides had good affinity for an 6-[(4-nitrobenzyl)thio]-9-beta-d-ribofuranosylpurine-sensitive mouse erythrocyte nucleoside transporter, with inhibition constants in the range of 0.

Pharmacokinetics and metabolism of 5-125I-iodo-4'-thio-2'-deoxyuridine in rodents.

Unlabelled: Pharmacokinetics and metabolite analysis of radioiodinated 5-iodo-4'-thio-2'-deoxyuridine (ITdU), a potential tumor cell proliferation-imaging agent, were investigated in rodents.

Methods: Blood and urine metabolites of radiolabeled ITdU were analyzed by thin-layer chromatography in rats. Tissue fractionation studies in mice were also performed to investigate the incorporation of (125)I-ITdU into DNA.

Development of radioiodinated nucleoside analogs for imaging tissue proliferation: comparisons of six 5-iodonucleosides.

The aim of this study was to determine the most suitable iodonucleoside analogs for use in tissue proliferation imaging by means of single photon emission tomography (SPECT). In this study, 5-[(125)I]iodo-(2-deoxy-2-fluoro-4-thio-beta-D-arabinofuranosyl)uracil ([(125)I]FITAU, 1E) and 5-[(125)I]iodo-1-methyl-(2-deoxy-2-bromo-beta-D-arabinofuranosyl)uracil ([(125)I]IMBAU, 1F) were synthesized and their biological data were compared with previously published results regarding 4'-thio nucleoside analogs and the reference compound 5-[(125)I]iodo-(2-deoxy-2-fluoro-beta-D-arabinofuranosyl)uracil ([(125)I]FIAU, 1D). 5-Iodo-(2-deoxy-2-fluoro-beta-D-arabinofuranosyl)uracil (FIAU, 2D), 5-iodo-(2-deoxy-2-fluoro-4-thio-beta-D-arabinofuranosyl)uracil (FITAU, 2E), and 5-iodo-1-methyl-(2-deoxy-2-bromo-beta-D-arabinofuranosyl)uracil (IMBAU, 2F) were successfully labeled with (125)I and their in vitro cytosolic thymidine kinase (TK(1)) phosphorylation, recombinant thymidine phosphorylase enzymatic catabolism, TK(1)-dependent cell uptake, and in vivo biodistribution in normal mice were evaluated.