The pharmacokinetics, excretion, and tissue distribution of [(14)C]-labeled polyethylene glycol-alanine (PEG-Ala) were determined after slow bolus administration into the femoral vein of male CD-1 mice. The pharmacokinetics of PEG-Ala in blood and plasma revealed a biphasic elimination with a terminal half-life of 20 h. Eighty-five percent of the excreted material was voided in the urine and th...

Atovaquone is an antiprotozoal compound with good in vitro stability against metabolic inactivation. Previous human studies which did not involve radiolabelling had not accounted for a substantial proportion of the dose. The possible metabolism of atovaquone in men was examined in a radiolabelling study involving four healthy male volunteers. Radioactivity was eliminated almost exclusively via ...

The pathway for the biosynthesis of new cardiolipin was investigated in the isolated perfused intact rat heart. Isolated rat hearts were perfused in the Langendorff mode for up to 60 min with Krebs-Henseleit buffer containing 0.1 microM [U-14C]glycerol. Analysis of radioactivity incorporated into phospholipids in the organic phase revealed an increase in radioactivity incorporated into phosphat...

Radioactivity in adrenal medullary chromaffin cells of the mouse was examined by autoradiographic methods 15 min to 1 hr after an intraperitoneal injection of 3H-dopa. In the normal control mice, the concentration of radioactivity was significantly higher in the A cells than in the NA cells, whereas in the hypophysectomized mice (9 days after operation by the transauricular method) the radioact...

The fission rate during JCO criticality accident is estimated from fission-product (FP) radioactivities in a uranium solution sample taken from the preparation basin 20 days after the accident. The FP radioactivity data are taken from a report by JAERI released in the Accident Investigation Committee. The total fission number is found quite dependent on the FP radioactivities and estimated to b...

OBJECTIVE Arterial input function represents the delivery of intravascular tracer to the brain. The optimal setting of this function is essential for measuring regional cerebral blood flow (rCBF) based on the microsphere model using N-isopropyl-4-[123I]iodoamphetamine (123I-IMP), in which the arterial 123I-IMP concentration (integral value) during the initial 5 min is usually applied. We develo...

An oceanographic investigation within 1.0km radius of Fukushima Daiichi nuclear power plant (FDNPP) was carried out in September 2013, independent of the Government of Japan. Samples of seawater and seafloor sand were collected near the sewage outlets and in front of the harbor at the FDNPP. The level of seawater radioactivity did not show evidence of immediate harm to the health of the people....

Positron emission tomography (PET) is a new tracer technique by which short-lived radionuclides, such as 11C are used for labeling drugs, amino acids and other compounds. The concentration in the various organs is determined non-invasively after I.V. injection. Positrons, emitted by 11C attract an electron, and the two masses are annihilated by emitting photons. These can be registered by exter...

Some analytical functions were tested for goodness of fit to standard curves in radio-immunoassays of insulin (Hales & Randle, 1963). Letting a, b and c be parameters, and y the radioactivity measured at an insulin concentration of x, excellent fit was obtained with the function 1/(y+c)=ax+b. This function was associated with a smaller variance around y and a greater number of sign changes for ...

Polycyclic aromatic hydrocarbons (PAHs) are lipophilic organic pollutants occurring widely in the terrestrial environment. To study the transfer of PAHs in the food chain, pigs have been fed with milk spiked either with [(14)C]phenanthrene or with [(14)C]benzo[a]pyrene. The analysis of blood radioactivity showed that both PAHs were absorbed with a maximum concentration at 5--6 h after milk inge...