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Sample records for 3h 14c 32p

  1. Lethal Effect on Bacterium of Decay of Incorporated Radioactive Atoms (3H, 14C, 32P)

    The biological effect of decay of 3H, 14C and 32P incorporated into a bacterium depends on the nature of the organic molecule labelled, on the position of the isotope within it and on the isotope itself. In sum, results obtained to date show that: The decay of 3H atoms incorporated into certain macromolecules of a bacterium causes sterilization through ionization by the ß- particle emitted; transmutation is of negligible importance. This self-irradiation is comparable in effect with X-rays and is affected in a similar manner by the same factors: temperature, presence of a radioprotector, radiosensitivity of the strain. Decay of 14C or 32P atoms incorporated into bacterial DNA is lethal because of the transmutation effect; ionizations produced by emitted ß- particles may be disregarded. Survival curves for 32P transmutations depend on the experimental conditions. Some of the results obtained with 32P are similar to those obtained with X-rays, e.g. effects of temperature, radical capture and oxygen, while others are similar to those of u.v. light, e.g., effect of growth conditions. Comparative tests made with 32P indicate that the recoil energy of transmutation is not the phenomenon responsible for the lethal effect observed. Comparison of the results obtained after X-irradiation or decay of 3H or 32P incorporated into the DNA of bacteria of the same strain of E. coli shows that the efficiency of a 32P transmutation is about four times greater than that of an ionization produced at random within the same DNA. (author)

  2. Synthesis of psilocin labelled with 14C and 3H

    14C- and 3H-labelled psilocin (4-hydroxy-N,N-dimethyl-tryptamine), the principal, active agent of hallucinogenic mushrooms, was synthesized from 2-methyl-3-nitrophenol via 4-benzyloxyindole. 14C-Labelled potassium cyanide was reacted with 4-benzyloxygramine (obtained from 4-benzyloxyindole) to give 14C-4-benzyloxy-3-indole acetic acid, an intermediate for 14C-psilocin synthesis. 3H-Labelled lithium aluminium hydride was used to react with 4-benzyloxy-3-indole-N,N-dimethyl-glyoxylamide (obtained from 4-benzyloxyindole) to give 3H-4-benzyloxy-psilocin which was debenzylated to form 3H-psilocin. (author)

  3. Synthesis of 3H and 14C labelled changrolin

    3 kinds of [14C] and [3H] changrolin labelled at different positions (I, II, III) were prepared. The synthesis of I is as follows: (Scheme 1): Heating 5-bromoanthranilic acid with formamide yielded IV, which on heating with POCl3 gave V. Condensation of V with 4-aminophenol and Mannich reaction produced 6-bromochangrolin (VI). Catalytic dehalogenation of VI with tritium gas gave I. The synthesis of II was started from (14C) formamide and anthranilic acid. Labelled 4-chloroquine obtained was condensed with Mannich base (VII) directly (Scheme 2). III was prepared by 1 step with (14C) formaldehyde (Scheme 1)

  4. Plasmid DNA labelled with 14C or 3H

    Plasmid DNA labelled with 14C or 3H in thymine was isolated from the thymine-dependent strain of Escherichia coli 15 SPT bacteria. The specific activity of the plasmid DNA preparations lay in the range from 0.5 to 20 MBq/mg, their relative molecular weight was 1.7 x 106 dalton. Molecular weight, preparation purity, and the degree of damage of the plasmid DNA molecules were examined by UV absorption spectroscopy, by gel electrophoresis, and by electron micrography. The quality of the [thymine-2-14C] plasmid DNA was verified in a diagnostic test for the determination of the anti-dsDNA bonding activity in human serum. (author). 1 tab., 5 figs., 30 refs

  5. Lymphokine-induced uptake of [14C]glucosamine, [14C]glucose, and [3H]leucine by macrophages

    Lymphokine-activated (LK+) and control (LK-) macrophages were cultured for 66 h and then pulsed with [14C]glucosamine. Uptake of [14C]glucosamine was greater in LK+ than in LK- cultures. If, after 66 h, the medium was replaced with fresh medium and then pulsed with either [14C]glucose or [14C]glucosamine, the uptake of isotope was greatly reduced compared to cultures with no change of medium. However, uptake of both radiolabeled substances was still found to be greater in LK+ cultures than in LK- cultures. Although uptake of both substances was enhanced by lymphokines, the uptake kinetics of each isotope was different. Under similar conditions the uptake of [3H]leucine was not enhanced by lymphokine activation. These data are interpreted to mean that LK+ macrophages are metabolically stimulated and utilize more glucose and glucosamine. The difference in kinetics implies a different utilization by macrophages for each substance

  6. Measuring techniques for environmental 3H, 14C and 222Rn by liquid scintillation counter

    Measuring techniques for environmental 3H, 14C and 222Rn with a liquid scintillation counter have been studied. 3H in environmental water was enriched by electrolysis and measured with a low background liquid scintillation counter. By this technique, 3H concentration of ground water, river water, sea water and rain water at Tokyo was founded to be 0.1 ∼ 2.5 Bq/1. 14C in taurine and ethyl-alcohol was measured directly liquid scintillation counter. By this 14C measuring, natural products, contain low level 14C, were distinguished from synthesised products contain no 14C. 222Rn in toluene extracted from environmental water or air was measured by scintillation pulse interval analysis method. By this technique, 222Rn was able to be measured under very low background counting rate, 0.03cpm, and high efficiency. (author)

  7. Establishing release limits for 3H, 14C, 85Kr, and 129I

    Tritium (3H), 14C, 85Kr, and 129I are the most important globally dispersed radionuclides released from the nuclear fuel cycle. In this paper, we investigate whether global transport of these radionuclides could also be important in assessing doses to individuals in critical groups of the population

  8. The serum 14C-triolein/3H-oleic acid assimilation test for differential diagnosis of maldigestion and malabsorption

    In 125 consecutive patients the measurement of serum radioactivities after simultaneous ingestion of 14C-triolein and 3H-oleic acid was investigated as a test of lipid assimilation. The sum of the 2-h and 4-h concentrations of 14C in serum (se(2+4)14C) was most useful as an index of lipid assimilation, and the 2-h serum 3H/14C ratio (se-3H/14C) reflected lipid digestion. Normal values were se(2+4)14C >= 1.0% of the dose ingested per litre serum and se-3H/14C14C correlated significantly with faecal fat (r = -0.56, P 7 g/day. False-negative values appeared mainly in the patients with moderate steatorrhoea and gastrointestinal anastomoses. Only one false-positive se(2+4)14C value was found. Se-3H/14C was abnormal in 24 of the 34 patients with maldigestion with two false-positive results. When the results of se(2+4)14C and se-3H/14C were combined, the predictive value of the test result '' normal lipid assimilation'' was 0.75, that of the test result ''maldigestion'' was 0.93 and that of ''malabsorption'' 0.71. It is concluded that the serum 14C-triolein/3H-oleic acid assimilation test is convenient and inexpensive and may be useful when quantitative faecal collections are not available

  9. Environmental 14C and 3H activities: global trends and local contamination

    The anthropogenic disturbance of natural distributions of radiocarbon ( 14C) and tritium (3H) due to the release of bomb-produced isotopes occurred after the World War II and at the same time the monitoring of these isotopes started at several stations in the world. Radioactive isotopes 14C and 3H, together with the stable isotopes 2H and 18O, are very important tracers in environmental, climatological and hydrological studies. Monitoring of environmental levels of 14C and 3H in Croatia started more then 20 years ago, while that of the stable isotopes somewhat later. The monitoring was performed at the three types of stations: a) 'clean-air' sites, which are supposed to reflect only the global disturbance of the atmospheric isotope concentrations, b) in a densely populated industrial center, where the effect of intense fossil-fuel combustion is expected, and local contamination from institutions using radioactive-labeled material is also possible, and c) at locations around the Nuclear Power Plant Krsko. The mean yearly 3H activities in precipitation continuously decrease since the beginning of monitoring approaching slowly the natural equilibrium. The monthly 3H activities show seasonal variations, with maximum in early summer and minimum in early winter. Both seasonal variations and the decrease of the mean yearly values are typical for continental stations of the Northern Hemisphere. At the sampling site located at the Institute, several periods of higher 3H activities were observed, due to the local contamination with the tritium-labeled material. The 14C concentration in the atmosphere shows also the continuous decrease of the mean yearly values and superposed seasonal fluctuations, with higher activity during summer. Seasonal peak-to-peak variations are higher in the area of the city of Zagreb than at the clean-air site on the mountain (about 1000 m a.s.l.). This difference is caused by the introduction of CO2 (containing no 14C isotope) produced by fossil

  10. Implementing methods for 3h and 14c measurement in organic waste samples

    The paper presents the results obtained from the implementation of the 3H and 14C measurement methods on the TriCarb 3110TR using Normal Count Mode (typical count rate > 500CPM). Two types of organic solutions were used: 3H in toluene, with activity of 44886.51dpm/ml and 14C SPEC-CHEC solution with activity of 929000dpm/ml. To determinate counting efficiency and calculate DPM (Disintegrations Per Minute), quench curves must be performed for each radionuclide. These curves are obtained using a quench standards set, each containing the same amount of nuclide with varying amounts of quenching agent. The high values obtained by both methods for efficiency recovery of 3H and 14C indicate very good measurement efficiency (for tritium in the range 0-18.6keV, the minimum acceptable efficiency is 60% while for carbon-14 in the range 0-156keV, the minimum acceptable efficiency is 95%). (authors)

  11. Kinetics of [32P]orthophosphate and [3H]thymidine incorporation into newly replicating DNA in vivo

    Nuclear DNA can be empirically subdivided into three populations: (1) bulk DNA or low salt-soluble DNA (75%), (2) high salt-soluble DNA (23%), and (3) matrix DNA which remains tightly bound to the nuclear matrix (2%). Newly replicating DNA is associated with the nuclear matrix in regenerating rat liver. To study the incorporation of DNA precursors into replicating DNA via the salvage vs the de novo pathway, 100μCi [3H]thymidine (3H-Thd) and 5mCi [32P]orthophosphate (32P/sub i/) were injected into the hepatic portal vein of partially hepatectomized rats. Increasing time of 3H-Thd incorporation showed the label is chased from matrix DNA to bulk DNA. After a 10 min pulse, 13% of the total specific activity is associated with bulk DNA and 57% with matrix DNA. After 30 min, 32% and 36% of the total specific activity remain associated with bulk and matrix DNA, respectively, indicating that most of the 3H has been chased from the matrix DNA. In contrast, after injection of 32P/sub i/, the amount of label in matrix DNA increases to a maximum at 30 min and only then begins to decrease. At 10 min the specific activity/total specific activity of bulk DNA is 7% and of matrix DNA is 66% vs 8% and 82% after 30 min. The kinetic pattern of 32P/sub i/ incorporation differs dramatically from that of 3H-Thd suggesting (a) the incorporation of de novo precursors lags significantly behind that of precursors entering through the salvage pathway, or (b) there may be two distinct classes of replication forks

  12. Using 14C and 3H to understand groundwater flow and recharge in an aquifer window

    A. P. Atkinson

    2014-06-01

    14C ages are between 100 and 10 000 years. 3H activities are negligible in most of the groundwater and groundwater electrical conductivity in individual areas remains constant over the period of study. Although diffuse local recharge is evident, the depth to which it penetrates is limited to the upper 10 m of the aquifer. Rather, groundwater in the Gellibrand Valley predominantly originates from the regional recharge zone, the Barongarook High, and acts as a regional discharge zone where upward head gradients are maintained annually, limiting local recharge. Additionally, the Gellibrand River does not recharge the surrounding groundwater and has limited bank storage. 14C ages and Cl concentrations are well correlated and Cl concentrations may be used to provide a first-order estimate of groundwater residence times. Progressively lower chloride concentrations from 10 000 years BP to the present day are interpreted to indicate an increase in recharge rates on the Barongarook High.

  13. Using 14C and 3H to understand groundwater flow and recharge in an aquifer window

    Atkinson, A. P.; Cartwright, I.; Gilfedder, B. S.; Cendón, D. I.; Unland, N. P.; Hofmann, H.

    2014-12-01

    Knowledge of groundwater residence times and recharge locations is vital to the sustainable management of groundwater resources. Here we investigate groundwater residence times and patterns of recharge in the Gellibrand Valley, southeast Australia, where outcropping aquifer sediments of the Eastern View Formation form an "aquifer window" that may receive diffuse recharge from rainfall and recharge from the Gellibrand River. To determine recharge patterns and groundwater flow paths, environmental isotopes (3H, 14C, δ13C, δ18O, δ2H) are used in conjunction with groundwater geochemistry and continuous monitoring of groundwater elevation and electrical conductivity. The water table fluctuates by 0.9 to 3.7 m annually, implying recharge rates of 90 and 372 mm yr-1. However, residence times of shallow (11 to 29 m) groundwater determined by 14C are between 100 and 10 000 years, 3H activities are negligible in most of the groundwater, and groundwater electrical conductivity remains constant over the period of study. Deeper groundwater with older 14C ages has lower δ18O values than younger, shallower groundwater, which is consistent with it being derived from greater altitudes. The combined geochemistry data indicate that local recharge from precipitation within the valley occurs through the aquifer window, however much of the groundwater in the Gellibrand Valley predominantly originates from the regional recharge zone, the Barongarook High. The Gellibrand Valley is a regional discharge zone with upward head gradients that limits local recharge to the upper 10 m of the aquifer. Additionally, the groundwater head gradients adjacent to the Gellibrand River are generally upwards, implying that it does not recharge the surrounding groundwater and has limited bank storage. 14C ages and Cl concentrations are well correlated and Cl concentrations may be used to provide a first-order estimate of groundwater residence times. Progressively lower chloride concentrations from 10

  14. 3H- and 14C-labelling of the aromatase inhibitor ZK 138723

    It has been known for several years that the growth of certain neoplastic disorders - especially breast cancer in women -depends on the serum level of estrogen. One strategy of lowering the estrogen formation is to inhibit the action of the enzyme aromatase, which catalyzes the final step in estrogen biosynthesis in humans. For this purpose nonsteroidal compounds seem to offer advantages as compared to the classical steroid derivatives regarding intensity and duration of effect as well as selectivity to other cytochrome P450 enzymes. The competitive aromatase inhibitor ZK138723 is such a nonsteroidal compound. It was labelled with 3H and 14C to be used for further pharmacological investigations. (author)

  15. Radiochemical analysis of 3H, 14C, 55Fe, 63Ni in waste samples

    Full text: In the nuclear waste from decommissioning of a nuclear facility, most of the beta activity is contributed from 14C, 3H, 55Fe, and 63Ni, especially in the first 10 years after the close of reactor. The determination of these radionuclides in radioactive waste is important for decommissioning and disposal of the waste. 14C, 3H, and 63Ni I are pure beta emitter; and 55Fe decay by electron capture. It is therefore necessary to decompose sample and separate individual radionuclide from matrix element and other interfering nuclides before measurement of their radioactivity. In our laboratory, analytical methods have been developed for the determination of these radionuclides in various nuclear wastes for the decommissioning of nuclear facilities. An oxidizing combustion method has been developed to decompose graphite, concrete, metals, and other solid samples. 14C and 3H released from the sample are separated trapped and measured by liquid scintillation counter (LSC). By this method the sample preparation time can be shortened to only 2-3 minutes. The detection limit of this method for 14C and tritium are 0.96 and 0.58 Bq/g graphite and 0.11 and 0.06 Bq/g concrete respectively. The interference of other radionuclides in samples is insignificant. A radiochemical separation procedure based on precipitation, ion exchange and extraction chromatography have been developed for the determination of 55Fe and 63Ni. The decontamination factors of the developed method are higher than 104 for the interfering radionuclides. The chemical recoveries for both Fe and Ni are higher than 80%. The detection limits of this method are 0.018 Bq for 55Fe and 0.014 Bq for 63Ni. The developed method has been successfully applied for the analysis of heavy concrete, graphite, steel, aluminium, and lead from nuclear reactor and the estimation of inventories of these radionuclides in nuclear waste have been carried out. In addition, the methods were also applied for the analysis of

  16. Threshold groundwater ages and young water fractions estimated from 3H, 3He, and 14C

    Kirchner, James; Jasechko, Scott

    2016-04-01

    It is widely recognized that a water sample taken from a running stream is not described by a single age, but rather by a distribution of ages. It is less widely recognized that the same principle holds true for groundwaters, as indicated by the commonly observed discordances between model ages obtained from different tracers (e.g., 3H vs 14C) in the same sample. Water age distributions are often characterized by their mean residence times (MRT's). However, MRT estimates are highly uncertain because they depend on the shape of the assumed residence time distribution (in particular on the thickness of the long-time tail), which is difficult or impossible to constrain with data. Furthermore, because MRT's are typically nonlinear functions of age tracer concentrations, they are subject to aggregation bias. That is, MRT estimates derived from a mixture of waters with different ages (and thus different tracer concentrations) will systematically underestimate the mixture's true mean age. Here, building on recent work with stable isotope tracers in surface waters [1-3], we present a new framework for using 3H, 3He and 14C to characterize groundwater age distributions. Rather than describing groundwater age distributions by their MRT, we characterize them by the fraction of the distribution that is younger or older than a threshold age. The threshold age that separates "young" from "old" water depends on the characteristics of the specific tracer, including its history of atmospheric inputs. Our approach depends only on whether a given slice of the age distribution is younger or older than the threshold age, but not on how much younger or older it is. Thus our approach is insensitive to the tails of the age distribution, and is therefore relatively unaffected by uncertainty in the distribution's shape. Here we show that concentrations of 3H, 3He, and 14C are almost linearly related to the fractions of water that are younger or older than specified threshold ages. These

  17. Using 3H and 14C to constrain the degree of closed-system dissolution of calcite in groundwater

    Highlights: ► δ13C and 87Sr/86Sr in Ovens groundwater imply substantial carbonate dissolution. ► 3H vs. 14C imply negligible closed-system calcite dissolution. ► Calcite dissolution largely open-system process. ► Recognising open-system calcite dissolution important for dating deeper groundwater. - Abstract: This study uses 3H concentrations, 14C activities (a14C), 87Sr/86Sr ratios, and δ13C values to constrain calcite dissolution in groundwater from the Ovens catchment SE Australia. Taken in isolation, the δ13C values of dissolved organic C (DIC) and 87Sr/86Sr ratios in the Ovens groundwater imply that there has been significant calcite dissolution. However, the covariance of 3H and 14C and the calculated initial 14C activities (a014C) imply that most groundwater cannot have dissolved more than 20% of 14C-free calcite under closed-system conditions. Rather, calcite dissolution must have been partially an open-system process allowing 13C and 14C to re-equilibrate with CO2 in the unsaturated zone. Recognising that open-system calcite dissolution has occurred is important for dating deeper groundwater that is removed from its recharge area in this and other basins. The study is one of the first to use 14C and 3H to constrain the degree of calcite dissolution and illustrates that it is a valuable tool for assessing geochemical processes in recharge areas

  18. Methylphenidate-like stimulants in vitro release [3H]tyramines but not [14C]dopamine

    The effects of methylphenidate, cocaine, nomifensine and amfonelic acid on the simultaneous uptake and release of [14C]dopamine and [3H]p-tyramine or [3H]m-tyramine were examined in rat striatal slices. While the uptake of each amine was inhibited equally by each drug, only [3H]tyramines were released. The d-amphetamine-induced release of [14C]dopamine and [3H]p-tyramine was antagonized by these drugs. These findings suggest that the tyramines can be transported independently from dopamine. (Auth.)

  19. Synthesis of N-(4-pyridyl[14C]carbonylamino)-1,2,[3H]3,6-tetrahydropyridine and the mono-labelled [14C]- and [3H]-analogues

    Reaction of isonicotinic [14C] acid hydrazide with the Zinke salt afforded N-(4-pyridyl [14C] carbonylimino)pyridinium yield (A) in 81% chemical yield. Sodium borohydride reduction of (A) gave N-(4-pyridyl [14C] carbonylamino)-1,2,3,6-tetrahydropyridine in 60% chemical yield with a specific activity of 6.17 mCi mM-1. Alternatively reduction of N-(4-pyridylcarbonylimino) pyridinium yield using absolute ethanol and [3H]-water as solvent yielded N-(4-pyridylcarbonylamino)-1,2,[3H]3,6-tetrahydropyridine in 52.6% chemical yield with a specific activity of 1.14 mCi mM-1. N-(4-Pyridyl[14C]carbonylamino-1,2,[3H]3,6-tetrahydropyridine was similarly prepared by sodium borohydride reduction of (A) using absolute ethanol and [3H]-water as solvent in 46% chemical yield with specific activities of 1.31 and 5.66 mCi mM-1 respectively for [3H] and [14C]. (author)

  20. Influence of boron nutrition on net uptake and efflux of 32P and 14C-glucose in Helianthus annuus roots and cell cultures of Daucus carota

    32P and 14C-glucose uptake were reduced under B deficiency in both Daucus cell suspensions and Helianthus roots. Similarly, efflux rates were found to be smaller in B deficient material. Efflux rates tended to be more affected than net uptake of both 32P and glucose. This may explain why sunflower roots showed a higher glucose net uptake immediately after transferring from a B sufficient to a B deficient nutrient solution. The data confirm earlier findings of B as an essential element for membrane function and integrity. B-deficiency effects could be reversed by the addition of B within less than one hour. Cell suspensions reacted similarly to roots with respect to B deficiency and may thus be suitable for further research on B deficiency effects. (orig.)

  1. Synthesis of 14C- and 3H-labelled 4-(4-nitrophenyl)aminophenylisothiocyanate (Go 9333/CGP 4540; amoscanate)

    Amoscanate, a broad spectrum anthelmintic, labelled with carbon-14 on the isothiocyanate carbon atom was prepared in an overall yield of 13% at a specific activity of 4.13 μCi/mg from potassium [14C]thiocyanate. The 4-nitro[U-14C]phenyl ring labelled compound was synthesized in 20.4% overall yield from [U-14C]aniline at a specific activity of 12.2 μCi/mg. The corresponding tritiated compound was prepared from 4-amino[2-3H]acetanilide at 112 μCi/mg. Labelling with tritium in the aromatic ring bearing the isothiocyanate group was achieved by catalysed halogen-tritium replacement. However, for pharmacokinetic and metabolism studies in experimental animals, the 14C- and 3H-labels associated with the phenylisothiocyanate moiety subsequently proved disadvantageous because of the instability of the labels in vivo. (author)

  2. Respiratory strategy is a major determinant of [3H]water and [14C]chlorpyrifos uptake in aquatic insects

    Buchwalter, D.B.; Jenkins, J.J.; Curtis, L.R.

    2002-01-01

    Despite the extensive use of aquatic insects to evaluate freshwater ecosystem health, little is known about the underlying factors that result in sensitivity differences between taxa. Organismal characteristics (respiratory strategy and body size) were used to explore the rates of [3H]H2O and [14)C]chlorpyrifos accumulation in aquatic insects. Ten aquatic insect taxa, including ephemeropteran, trichopteran, dipteran, hemipteran, and coleopteran species, were exposed to [14C]chlorpyrifos (240 ng??L-1) and [3H]H2O for up to 12 h. Because exchange epithelial surfaces on the)integument are permeable to water, [3H]H2O was used as a quantitative surrogate for exposed cellular surface area.) [14C]Chlorpyrifos uptake rates were highly correlated with water permeability in all 10 taxa tested and largely covaried with body size and respiratory strategy. Rates were highest among smaller organisms on a per-weight basis and in taxa with relatively large external cellular surfaces such as gills. Air-breathing taxa were significantly less permeable to both [3)HH20 and [14C)C]chlorpyrifos. A method for labeling exposed epithelial surfaces with a fluorescent dye was developed. This technique allowed discrimination between exchange epithelium and barrier tissue on the integument. Fluorescent dye distributions on the body surface provided a rapid method for estimating exposed epithelium consistent with [3H]H2O and [14)C]chlorpyrifos accumulation.

  3. Standardization of 3H, 14C and 63Ni radiation sources by calorimetric method

    The calorimetric method of determination of activity of radionuclides 3H, 14C and 63Ni with low mean energies of β-particles has, as compare to other methods which had been used for determination of activity of these nuclides, a number of advantages, because a nuclide to be measured can be introduced into the calorimeter in any physical and chemical state. It is not necessary to distroy integrity ane leek-proofness of a source wnich can be of arbitrary type. There is no correction for absorption and self-absorption of β-particles and measuring instruments are relatively simple. As a limitation of this method is it's low sensitivity which can be owercomed by means of application of modern high sensitivity calorimeters. Such calorimeters have been developed in the Mendeleev All-Union research Institute. The calorimetric installation consists of 3 independent β-calorimeters of differential-double type, working in the regime of heat equilibrium and beeng intended for different by sise and shape sources. Then, there are thermostatting device of special desighn and electric measuring device. Number of thermocouples in each calorimeter is from 75 to 120 and sensitivity of calorimeters is from 2.45x10-7 to 4.5x10-7 Bt/mm depending on the type of calorimeter. Calorimeters are intended for measuring activities from 109 to 1012 Bk. Error of measurement of activities equals 0.8-1.5% (with confidence level of 0.99%). The main portion of error consists of error in the medium energy β-spectra. The calorimeter error itself is much more lower. Soueces, which have been measured in the calorimeter than can be used for preparation of solutions and sources of lower activity

  4. Uptake of [3H]PAH and [14C]urate into isolated proximal tubular segments of the pig kidney

    Segments of proximal convoluted (PCT) and proximal straight (PST) tubules of minipigs and normal-sized pigs were microdissected (without collagenase treatment) and incubated (30 min, 370C, pH 7.4) in Ringer solution (under O2) containing [3H]PAH (3.10-5 M) or [14C]urate (9.10-5 M) and, in inhibitor studies, probenecid, pyrazinoic acid (PZA), urate, or PAH, all at 1 mM. In both strains the uptake of [3H]PAH expressed as mean T/M ratio (cpm per ml tissue water/cpm per ml incubation medium) was significantly higher (P14C]urate. In eight minipigs the T/M was 4.9 +/- 0.5 in 24 PCT and 2 +/- 0.2 in 25 PST. In normal-sized pigs the T/M was 3.8 +/- 0.3 in 35 PCT (five pigs) and 1.9 +/- 0.4 in eight PST (two pigs). In inhibitor studies urate significantly depressed the uptake of [3H]PAH, and unlabeled PAH depressed the uptake of [14C]urate. PZA significantly inhibited the uptake of [14C]urate but not that of [3H]PAH, whereas probenecid had a strong inhibitory efect on the uptake of both compounds. These results suggest that [14C]urate and [3H]PAH are transported by a transport system located mainly in the proximal convoluted tubule. These findings are in contrast in the findings are in contrast to the findings obtained in rabbits in which the transport system of PAH and urate is mainly located in the proximal part of the pars recta

  5. Effects of hyperglycemia on glucose production and utilization in humans. Measurement with [3H]-2-, [3H]-3-, and [14C]-6-glucose

    Studies with tritiated isotopes of glucose have demonstrated that hyperglycemia per se stimulates glucose utilization and suppresses glucose production in humans. These conclusions rely on the assumption that tritiated glucose provides an accurate measure of glucose turnover. However, if in the presence of hyperglycemia the isotope either loses its label during futile cycling or retains its label during cycling through glycogen, then this assumption is not valid. To examine this question, glucose utilization and glucose production rates were measured in nine normal subjects with a simultaneous infusion of [3H]-2-glucose, an isotope that may undergo futile cycling but does not cycle through glycogen; [14C]-6-glucose, an isotope that may cycle through glycogen but does not futile cycle; and [3H]-3-glucose, an isotope that can both undergo futile cycling and cycle through glycogen. In the postabsorptive state at plasma glucose concentration of 95 mg X dl-1, glucose turnover determined with [14C]-6-glucose (2.3 +/- 0.1 mg X kg-1 X min-1) was greater than that determined with [33H]glucose (2.1 +/- 0.1 mg X kg-1 X min-1, P = 0.002) and slightly less than that determined with [3H]-2-glucose (2.7 +/- 0.2 mg X kg-1 X min-1, P = 0.08). Plasma glucose was then raised from 95 to 135 to 175 mg X dl-1 while insulin secretion was inhibited, and circulating insulin, glucagon, and growth hormone concentrations were maintained constant by infusion of these hormones and somatostatin. Glucose production and utilization rates determined with [14C]-6-glucose continued to be less than those determined with [3H]-2-glucose and greater than those seen with [3H]-3-glucose

  6. Effect of aldicarb on growth and radio-carbon (14C) and radio-phosphorus (32P) assimilation by Rhizobium japonicum

    In vitro studies on the effect of aldicarb (2-methyl-2-(methyl thio) propionaldehde-o-methyl carbamoyl oxime), a soil applied systemic insecticide, on Rhizobium japonicum revealed that the chemical (at 1,2 and 5 ppm levels) stimulated the growth of the organism initially upto 48 hr which declined thereafter upto 72 hr. The incorporation of 14C-glucose by the cells considerably reduced due to the insecticide treatment. The production of extracellular, water-soluble slime (polysacchardes) was also reduced considerably with increased concentrations of the chemical. However, the incorporation of 14C-radio-activity in the extracellular slime generally enhanced due to the treatment, upto 6 hr after injection of the radioactivity, which declined significantly later at 15 hr, indicating a qualitative difference in the extracellular polysaccharides produced by the insecticide treated cells. The insecticide treatment drastically reduced the incorporation of 32P-disodium hydrogen phosphate into Rhizobium cells, but enhanced the specific activity of the extracellular polysacchrides. (author)

  7. Reduced permeation of 14C-sucrose, 3H-mannitol and 3H-inulin across blood-brain barrier in nephrectomized rats

    Experiments were carried out to determine if changes in the concentration-time profile of a blood-borne radiotracer such as 14C-sucrose would spuriously alter measurements of its permeation across the blood-brain barrier (permeability-area product, PA) based on a 2-compartment (plasma/brain) simple diffusion model. Anesthetized rats which were bilaterally nephrectomized and given a standard intravenous bolus injection of 14C-sucrose, 3H-mannitol or 3H-inulin exhibited an elevated plasma tracer concentration compared to control animals. However, tracer concentration measured in brain parenchyma after 30 min was not proportionally elevated, and PA calculated from the ratio, parenchymal tracer concentration: plasma concentration-time integral, was significantly reduced below control values. In control rats, distortion and elevation of the plasma 14C-sucrose profile by continuous intravenous infusion did not result in lowered PA values. This suggested that the lowering of PA by nephrectomy reflected reduced cerebrovascular permeability or area or other cerebral influence rather than a deficiency in the 2-compartment model for PA measurement

  8. Energy Metabolism and Transfer of 3H and 14C in Mammals and Birds - Energy metabolism and transfer of 3H and 14C in mammals, birds, and fish

    The transfer of 3H and 14C in environment needs to be modelled differently than that of other radionuclides released from nuclear facilities because hydrogen and carbon are key components of biological tissues and the carbon and hydrogen life cycles. A detailed understanding of the behaviour of 3H and 14C in the food chain is essential because 3H may be released in large quantities from CANDU (Canadian Deuterium Uranium) reactors and future thermonuclear reactors, and 14C accumulates in the environment because of its long half-life. In recent years, the authors published both a simple and a complex dynamic metabolic model for 3H and 14C transfer to farm and wild animals. The models applications for wild animals were restricted to few examples. There is an increased interest to extend the models for a larger selection of wild animals, birds and fish to support developments such as the International Commission for Radiological Protection (ICRP) environmental protection framework. In this paper we describe activities to expand 3H and 14C models to cover a wider range of wildlife. The updated model of the dynamics of tritium transfer in aquatic food chains (AQUATRIT model) developed by the authors was successfully tested for small and large (trout) fish. Wild mammals and birds generally have a lower fat content than domestic species and must adapt to variable environmental conditions. The body mass is an important parameter involved in radionuclide transfer. The environmental temperature, type of animal, and diet must also be considered. The model input parameters for wild mammals are poorly defined because the experimental data are too few and the intraspecific variability is higher than that for farm and laboratory mammals. In the present study, our previously published approach considering the use of energy metabolism and the link between energy and organic matter turnover rate at the whole body and organ level is expanded for selected mammals, birds and fish. A

  9. Energy Metabolism and Transfer of {sup 3}H and {sup 14}C in Mammals and Birds - Energy metabolism and transfer of {sup 3}H and {sup 14}C in mammals, birds, and fish

    Melintescu, Anca; Galeriu, Dan [' Horia Hulubei' National Institute for Physics and Nuclear Engineering, Department of Environmental Physics and Life, 30 Reactorului St., POB MG-6, Bucharest-Magurele, RO-077125 (Romania); Beresford, Nicholas A. [NERC Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Av. Bailrigg, Lancaster LA1 4AP (United Kingdom)

    2014-07-01

    The transfer of {sup 3}H and {sup 14}C in environment needs to be modelled differently than that of other radionuclides released from nuclear facilities because hydrogen and carbon are key components of biological tissues and the carbon and hydrogen life cycles. A detailed understanding of the behaviour of {sup 3}H and {sup 14}C in the food chain is essential because {sup 3}H may be released in large quantities from CANDU (Canadian Deuterium Uranium) reactors and future thermonuclear reactors, and {sup 14}C accumulates in the environment because of its long half-life. In recent years, the authors published both a simple and a complex dynamic metabolic model for {sup 3}H and {sup 14}C transfer to farm and wild animals. The models applications for wild animals were restricted to few examples. There is an increased interest to extend the models for a larger selection of wild animals, birds and fish to support developments such as the International Commission for Radiological Protection (ICRP) environmental protection framework. In this paper we describe activities to expand {sup 3}H and {sup 14}C models to cover a wider range of wildlife. The updated model of the dynamics of tritium transfer in aquatic food chains (AQUATRIT model) developed by the authors was successfully tested for small and large (trout) fish. Wild mammals and birds generally have a lower fat content than domestic species and must adapt to variable environmental conditions. The body mass is an important parameter involved in radionuclide transfer. The environmental temperature, type of animal, and diet must also be considered. The model input parameters for wild mammals are poorly defined because the experimental data are too few and the intraspecific variability is higher than that for farm and laboratory mammals. In the present study, our previously published approach considering the use of energy metabolism and the link between energy and organic matter turnover rate at the whole body and organ

  10. Autoradiography of 3H- and 14C-Thymidine in Bone Marrow by a Double-Emulsion Technique

    In the present work a new method has been developed to study the generation time of bone- marrow cells in cultures, after double labelling with 3H- and 14C-thymidine, by means of a double-emulsion autoradiographic technique. In such an investigation it is not practicable to use a single thick layer of emulsion since this prevents satisfactory staining of the bone marrow cells with Giemsa stain. If the specimen is stained before making the autoradiograph it must be covered with a protective layer to retain the stain and this absorbs a large proportion of the 3H-electrons. The technique adopted is a modification of the method described by Baserga and Nemeroff. The bone-marrow smear is covered with a very thin layer of the fine-grain Gevaert emulsion NUC 715. After an exposure suitable for the 3H-thymidine (1-5 d)the emulsion is processed and the bone marrow can be stained adequately through the thin emulsion. It is then dipped in a 7% solution of celloidin in amyl acetate to protect the stain during subsequent procedures (celloidin in ether-alcohol mixture removes the stain). The specimen is then dipped in Kodak NTB-2 emulsion having a larger grain size than the first emulsion, and exposed to 14C-electrons (2-6 weeks). The second emulsion can then be processed without affecting the staining of the bone-marrow smear. The celloidin layer is sufficiently thick to absorb all 3H-electrons so that an increase in grain density in the second emulsion is due to 14C electrons only. Moreover the celloidin layer still permits good autoradiographic resolution in the second emulsion. Autoradiographs in the first and second emulsion are easily recognised by the difference in grain size. It is thus possible to distinguish between cells containing only 3H-thymidine and only 14C-thymidine or both 3H- and 14C-thymidine. The interpretation of the results will be discussed. (author)

  11. 14C-leucine, 35S-methionine 3H-lysine, 14C-3-O-methyl-glucose and 3H-ABA transport in developing maize embryos

    To understand the development of the maize embryo the authors have studied the transport of 14C-leucine, 35S-methionine, 3H-lysine, 14C-3-O-methyl-glucose, and 3H-abscisic acid in isolated Tx5855 or sweet corn embryos. pH optima ranged from pH 4.2 for methionine, pH 5.0 and pH 5.75 for leucine, pH 6.5 for lysine, to pH 5.5-6.5 for 3-O-methyl-glucose. Uptake rates of all radiolabelled compounds were linear during the first three hrs of incubation. Only leucine showed a saturable component with an apparent Km 10-4M. When comparing the uptake rates during the entire range of embryogenesis in inbred line TX5855, leucine and 3-O-methyl-glucose show parallel changes in uptake rates (moles/gm fw/hr or moles/embryo/hr). In isolated sweet corn embryos, ABA (10-5 to 10-8M) showed no effect on 3-O-methyl-glucose or methionine uptake, but showed a 25-40% increase in leucine and lysine uptake as compared with no ABA addition. These characterizations of metabolite uptake provide a basis for the design of future studies with isolated maize embryos

  12. Improving of Quality Control and Quality Assurance in 14C and 3H Laboratory; Participation in the IAEA Model Project

    Full text: Users of laboratory's analytical results are increasingly requiring demonstrable proofs of the reliability and credibility of the results using internationally accepted standards, because the economic, ecological, medical and legal decisions based on laboratory results need to be accepted nationally and internationally. Credibility, respect and opportunities of the laboratories are improved when objective evidence on the reliability and quality of the results can be given. This is achieved through inculcation of a quality culture through definition of well-defined procedures and controls and operational checks characteristic of quality assurance and quality control (Q A/QC). IAEA launched in 1999 a two-and-a-half year model project entitled Quality Control and Quality Assurance of Nuclear Analytical Techniques with participation of laboratories using alpha, beta and/or gamma spectrometry from CEE and NIS countries. The project started to introduce and implement QA principles in accordance with the ISO-17025 guide, leading eventually to a level at which the QA system is self-sustainable and might be appropriate for formal accreditation or certification by respective national authorities. Activities within the project consist of semi-annual reports, two training workshops, two inspection visits of the laboratories by IAEA experts and proficiency tests. The following topics were considered: organisation requirements, acceptance criteria and non-conformance management of QC, internal and external method validation, statistical analyses and uncertainty evaluation, standard operation procedures and quality manual documentation. 14C and 3H Laboratory of the Rudjer Boskovic Institute has been one of ten laboratories participating in the Project. In the Laboratory all the procedures required in the quality control were included implicitly, while during the Model Project much effort has been devoted to elaboration of explicit documentation. Since the beginning of

  13. Designing of 14C, 3H-labeled liposomal preparations and their distribution in inner organs of experimental animals

    Full text: Development of methods for introduction of drug liposomal forms into practice is an urgent task for medicine and radiobiology. Per oral way of administration of the medications has been unexplored properly yet. Preservation of their stability in the gastro-intestinal tract is the essential requirement to the liposomes. Literature data and our studies showed that the elevated saturation of fatty acids and viscosity of liposomal membrane bilayer increases their stability to acidic and alkaline media of the digestive system. To prepare the liposome we used 14C,H-labeled lipids isolated from tissues by means of preparative chromatography after administration of D(1-614C)glucose (specific radioactivity 100 mkCu/mM) as well as of D(1-3H)-galactose (specific radioactivity 900 mkCU/mM) to 10 rats. Organ-specific liposomes were prepared in accordance with the special method without ultrasound processing to administered them with milk per orally to rats by means of a gastric probe. Before administration of 14C,3H liposomes the animals were not fed for 16-20 hours for complete emptying of the gastrointestinal tract. Under these conditions 1-1.5 hours after administration of liposomes their maximum amount was absorbed from he intestine. We found tissue specificity of the liposome administered. If the amount of administered liposomes for each tissue to be taken for 100%, in target organs their distribution (in %) would be as follows: 0.30/0.39 in the heart, 0.54/0.06 in the skeletal muscle, 0.4/0.6 in the brain, 4.2/10.2 in the spleen, 2.9/6.1 in the pancreas, 5.1/1.2 in the kidney. In these experiments liposomes had covering of 14C,3H-glycosphingolipids of the spleen. Under these conditions 3H-cAMP in the form of liposomes was administered to mice per orally to measure radioactivity (in cpm 100mg of tissue) in the organs. The values were as follows: 77±6.3 in the liver, 750±47 in the spleen, 250±19 in the kidney, 70±77 in the heart, 267±21 in the lung and 95

  14. Adrenal androgen 11β- and 19-hydroxylation: a study on kinetic isotope effect and metabolic switching of 3H and 14C labeled substrates

    Monooxygenations at 11β and 19 are two main metabolic pathways of androstenedione (A) by sheep and dog adrenals and could be catalyzed by a single cytochrome P-450 as observed for deoxycorticosterone metabolism with the bovine adrenal cytochrome P-450/sub 11β/. They found an unusually high apparent kinetic isotope effect (k/sub H//k/sub T/ = 11.7) on the 19-hydroxylation of [19-3H3, 4-14C]A with sheep and dog adrenal homogenates. They therefore attempted to assess the inverse secondary kinetic isotope effect of the simultaneously occurring 11β-hydroxylation. The substrate (16.1μM and 14.7μM, 3H/14C = 15.1 and 21.9 for sheep and dog, respectively) was incubated with adrenal tissue homogenate in the presence of NADPH for 1-10 min. The products were mixed with carrier standards and purified through TLC, acetylation, and countercurrent distribution to show constant 3H/14C ratio. The 3H/14C ratios of the major [19-3H3, 4-14C]-11β-OHA were found to be elevated 1.1-1.2 fold whereas those of [19-3H2, 4-14C]-19-OHA were decreased to 0.06 and the recovered A showed 0.95-0.99 of the initial ratio. While they observed a metabolic switching between the 2β- and 19-hydroxylations of [19-3H3, 4-14C]A with human placental aromatase (Fronckowiak and Osawa), it is suggested that adrenal non-aromatizing androgen 19-hydroxylation operates a metabolic switching with the 11β-hydroxylation

  15. Metabolism of high density lipoproteins reconstituted with [3H]cholesteryl ester and [14C]cholesterol in the rat, with special reference to the ovary

    In order to study the metabolism of high density lipoprotein (HDL)-carried sterol in the rat, human HDL was reconstituted with [14C]cholesterol and [3H]cholesteryl ester. After iv injection into immature PMSG-human CG primed rats pretreated with 4-aminopyrazolopyrimidine and aminoglutethimide, there was time-dependent accumulation of 3H and 14C in various organs which reached a maximum by 15-90 min. On a milligram wet weight basis, uptake of 3H and 14C was greatest in the adrenals, next in ovaries, followed by the liver, with little uptake by kidneys and spleen. On an organ basis, accumulation was greatest by the liver. Coadministration of excess unlabeled HDL, but not human low density lipoprotein, reduced accumulation of radioactivity by the ovaries and adrenals by 60%, indicating a specific and saturable uptake process. Granulosa cells cultured in lipoprotein-deficient medium with reconstituted HDL formed 3H- and 14C-labeled 20 alpha-hydroxypregn-4-en-3-one. Over a 24-h period, utilization of both [14C]cholesterol and [3H]cholesteryl ester was linear, but rates of utilization of the two sterol moieties were not parallel. Lysosomotropic agents had no effect on utilization of either free or esterified cholesterol for steroidogenesis but reduced degradation of 125I-labeled low density lipoprotein apoprotein. These findings lend further support to the concept of a distinct HDL pathway in steroidogenic cells of the rat

  16. Quality assurance for 14C and 3H measurements by GPC and LSC counting methods in the Zagreb Laboratory

    Laboratory for Measurements of Low-level Radioactivity of the Rudjer Boskovic Institute in Zagreb, Croatia, has been measuring 14C since 1968 and 3H since 1976 by applying gas (CH4) proportional counting (GPC) technique. By purchasing a Quantulus 1220 ultra low-level liquid scintillation counter (LSC) in 2002 two methods of chemical preparation of 14C samples have been implemented: a CO2 absorption method and a benzene synthesis method. The procedures for LSC measurement of both isotopes have been established. A 'good laboratory practice' was introduced since the beginning of the measurements in the Laboratory. The Laboratory Manual issued in 1994 covered most technical procedures required by the QC/QA system and management, including calibration of measurements, traceability, trackability and statistical evaluation of results. Laboratory participated in 4 radiocarbon and five tritium interlaboratory comparisons. A great progress in implementation of quality system was achieved during the participation in the IAEA project RER/2/004 'Quality Control and Quality Assurance of Nuclear Analytical Techniques' (1999-2001). The new Quality Assurance Manual includes the following documents conformed with ISO 17025 requirements: 6 administrative documents, 3 technical documents, 5 administrative procedures, 14 technical procedures, 3 documents of method validations, description of 3 programs and databases, 12 forms, 14 log books, 2 action plans, 3 lists of equipment and expenditures, and documentation on Laboratory personnel. Laboratory took part in three IAEA audits and two proficiency tests, and a constant progress was established. During the participation in the IAEA project a specific problem was the non-existence of implementation of quality system at the Institute level. Last year a new quality manager of the Institute was designated and the first version of the new Institute Quality Manual in accordance with ISO 17025 requirements was issued. Harmonization of the

  17. Synthesis of [3,5-14C]trachelanthamidine and [5-3H]isoretronecanol and their incorporation into the retronecine moiety of riddelliine in Senecio riddellii

    (+/-)-[3,5-14C]Trachelanthamidine and (+/-)-[5-3H]isoretronecanol, which are diastereomers, were prepared from potassium [14C]cyanide and [5-3H]proline, respectively. These compounds and [1,4-14C]putrescine were administered to Senecio riddellii plants resulting in the formation of labeled riddelliine, in which almost all the radioactivity was located in its retronecine moiety. The activity of the beta-alanine obtained by degradation of the retronecine was consistent with specific labeling of this pyrrolizidine base at the expected positions. The extremely high absolute incorporation (15.1, 22.1%) of trachelanthamidine into riddelliine strongly favors this 1-hydroxymethylpyrrolizidine as the one on the main biosynthetic pathway to retronecine. The lower incorporation (0.75%) of isoretronecanol may represent a minor or aberrant pathway to retronecine

  18. Estimation of rat muscle blood flow by microdialysis probes perfused with ethanol, [14C]ethanol, and 3H2O

    Stallknecht, B; Donsmark, M; Enevoldsen, L H;

    1999-01-01

    rates ranging from 0 to 21 ml. 100 g-1. min-1. The microdialysis probes were perfused at 2 microliter/min with perfusate containing ethanol, [14C]ethanol, and 3H2O. Within and between experiments outflow-to-inflow ratios (o/i) generally varied inversely with blood flow. When a low flow or no flow was...

  19. Over-estimation of glucose-6-phosphatase activity in brain in vivo. Apparent difference in rates of [2-3H]glucose and [U-14C]glucose utilization is due to contamination of precursor pool with 14C-labeled products and incomplete recovery of 14C-labeled metabolites

    Significant dephosphorylation of glucose 6-phosphate due to glucose-6-phosphatase activity in rat brain in vivo was recently reported. The evidence was an apparent more rapid 3H than 14C loss from the glucose pool and faster [2-3H]glucose than [U-14C]glucose utilization following pulse labeling of the brain with [2-3H,U-14C]glucose. Radiochemical purity of the glucose and quantitative recovery of the labeled products of glucose metabolism isolated from the brain were obviously essential requirements of their study, but no evidence for purity and recovery was provided. When we repeated these experiments with the described isolation procedures, we replicated the results, but found that: 1) the precursor glucose pool contained detritiated, 14C-labeled contaminants arising from glucose metabolism, particularly 2-pyrrolidone-5-carboxylic acid derived from [14C]glutamine; 2) [14C]glucose metabolite were not quantitatively recovered; 3) the procedure used to isolate the glucose itself produced detritiated, 14C-labeled derivatives of [2-3H,U-14C]glucose. These deficiencies in the isolation procedures could fully account for the observations that were interpreted as evidence of significant glucose 6-phosphate dephosphorylation by glucose-6-phosphatase activity. When glucose was isolated by more rigorous procedures and its purity verified in the present studies, no evidence for such activity in rat brain was found

  20. Differential blood-brain barrier permeabilities to [14C]sucrose and [3H]inulin after osmotic opening in the rat

    The blood-brain barrier (B-BB) in 3-month-old rats was opened unilaterally by infusing 1.8 m L(+)arabinose in water into the internal carotid artery through a catheter in the external carotid. Two poorly penetrating uncharged test radiotracers of differing molecular weight and size, [14C]sucrose (340 daltons, radius 5 A) and [3H]inulin (5500 daltons, radius 15 A), were simultaneously injected i.v. in untreated rats, or rats at 1, 30, or 50 min after infusion of hypertonic arabinose solution. Evans-blue solution was injected 5 min prior to osmotic treatment as a visual indicator of barrier integrity. In regions of uninfused control brains, the [14C]sucrose permeability-surface area (PA) product approximated 10(-5) s-1, whereas PA was not measurable for [3H]inulin. In arabinose-infused animals, PA products on the ipsilateral hemisphere for both [14C]sucrose and [3H]inulin were markedly elevated 6 min after infusion, but decreased by 35 and 55 min. In nearly all regions, statistically significant differences were not found between 6-min [14C]sucrose- and [3H]inulin-PA values (P greater than 0.05). However, at 35 and 55 min in most regions, the PA for [3H]inulin was significantly lower (P less than 0.05) than PA for [14C]sucrose. The results indicated that the B-BB closed more rapidly to larger than to smaller molecules after osmotic treatment and were consistent with a pore model for osmotic B-BB opening

  1. Synthesis of singly 2H-, 3H-, and 14C- and doubly labeled acetaminophen, phenacetin, and p-acetanisidine

    Several efficient procedures for the synthesis of deuterium, tritium, and 14C-labeled acetaminophen, phenacetin, and p-acetanisidine are described. p-Aminophenol was acylated by the appropriate acetic anhydride under mild conditions yielding labeled acetaminophen. With O-alkylation using NaCH2SOCH3 and appropriate labeled and unlabeled alkyl halides, labeled phenacetin and p-acetanisidine were also obtained. Phenacetin labeled both with 14C on the acyl group and deuterium on the ethoxy group was synthesized in high yield by acylation of p-phenetidine-d5. The last compound was obtained by acid hydrolysis of phenacetin-d5 synthesized previously. (author)

  2. Differential labeling of the subunits of respiratory complex III with [3H]succinic anhydride, [14C]succinic anhydride, and p-diazobenzene-[35S]sulfonate

    Exposure of antimycin-treated Complex III (ubiquinol-cytochrome c reductase) purified from bovine heart mitochondria to [3H]succinic anhydride plus [35S]p-diazobenzenesulfonate (DABS) resulted in somewhat uniform relative labeling of the eight measured subunits of the complex by [3H]succinic anhydride. In contrast, relative labeling by [35S]DABS was similar to [3H]succinic anhydride for the subunits of high molecular mass, i.e., core proteins, cytochromes, and the iron-sulfur protein, but greatly reduced for the polypeptides of molecular mass below 15 kDa. With Complex II depleted in the iron-sulfur protein the relative labeling of core protein I by exposure of the complex to [3H]succinic anhydride was significantly enhanced, whereas labeling of the polypeptides represented by SDS-PAGE bands 7 and 8 was significantly inhibited. Dual labeling of the subunits of Complex III by 14C- and 3H-labeled succinic anhydride before and after dissociation of the complex by sodium dodecyl sulfate, respectively, was measured with the complex in its oxidized, reduced, and antimycin-inhibited states. Subunits observed to be most accessible or reactive to succinic anhydride were core protein II, the iron-sulfur protein, and polypeptides of SDS-PAGE bands 7,8, and 9. Two additional polypeptides of molecular masses 23 and 12kDa, not normally resolved by gel-electrophoresis, were detected. Reduction of the complex resulted in a significant change of 14C/3H labeling ratio of core protein only, whereas treatment of the complex with antimycin resulted in decreases in 14C/3H labeling ratios of core proteins I and II, cytochrome c1, and a polypeptide of molecular mass 13kDa identified as an antimycin-binding protein

  3. Comprehensive analysis of collagen metabolism in vitro using [4(3H)]/[14C]proline dual-labeling and polyacrylamide gel electrophoresis

    A method to simultaneously quantify the production, secretion, and prolyl hydroxylation of individual types of collagen in cell culture samples has been developed. Collagens were biosynthetically labeled with a mixture of [14C]proline and [4-3H]proline. The labeled collagens were isolated and their component alpha-chains were resolved by sodium dodecyl sulfate/polyacrylamide gel electrophoresis. Migration of the collagen alpha-chains was determined by fluorography, and radioactivity in excised bands was quantified by scintillation counting. [14C]Proline labeling of collagen chains was used to determine the production and secretion of the different types of collagen. The ratios of the component alpha 1(I) and alpha 2(I) chains of type I collagen were also determined in this way. Prolyl hydroxylation of collagen alpha-chains was readily determined by measurement of their 3H:14C ratios. Following 4-hydroxylation, 3H was lost from the [4-3H]proline with alteration of this ratio. This dual-labeling method is suitable for the comprehensive analysis of collagen metabolism in multiple samples

  4. Low-level liquid scitillation counting for quantification of annual {sup 3}H and {sup 14}C concentrations in tree disks

    Kopka, B. [Goettingen Univ. (Germany). Isotopenlaboratorium fuer Biologische und Medizinische Forschung; Schikowski, J. [Goettingen Univ. (Germany). Isotopenlaboratorium fuer Biologische und Medizinische Forschung; Porstendoerfer, J. [Goettingen Univ. (Germany). Isotopenlaboratorium fuer Biologische und Medizinische Forschung

    1997-03-01

    The government of Schleswig Holstein funded a study to perform the retrospective determination of airborne {sup 3}H and {sup 14}C concentrations. It is well known, that in tree rings most of the hydrogen and cabron is fixed after insertion in the matrix of wood and that the radionuclide concentration correlates with former airborne activity concentrations. For the retrospective study wood disks of trees located in the region near the nuclear power plant of Kruemmel and control disks of unsuspected areas were selected. The hydrogen of the wood was transformed to water and the carbon to carbondioxide by classical oxidation processes (combustion in a furnace). The contents of {sup 3}H in the water and {sup 14}C of the carbondioxide (solved in scintillation liquid) were determined by liquid scintillation counting, using a low-level counter (type Quantulus 1220, Wallac). (orig.)

  5. Application of the efficiency tracing method to the liquid scintillation metrology of 3H and 14C dual-labelled samples

    Two calculation procedures have been tested for the application of the efficiency tracing method to the activity determination of 3H and 14C dual- -labelled samples in the liquid scintillation metrology. A procedure Ieads to the statement of a linear equations system as a function of the quenching parameter, while the other one uses a least-square algorithm to fit the total count rate against the quenching parameter. The first procedure is strongly sensitive to the statistical uncertainty on the partial efficiencies and produces discrepancies which may reach more than 100% compared to the real values. The second procedure leads to more reliable results, showing discrepancies between 0.1% and 0.6% for the 3H activity and between 0.6% and 5% for the 14C activity, as that the efficiency tracing method can be applied to the metro- logy of dual-labelled samples of 3H and 14C by means of this procedure. (Author) 7 refs

  6. Measurement of fat absorption using [3H]glycerol triether and [14C]glycerol trioleate in man

    A direct test of lipid absorption has been developed using [2H] glycerol triether as a lipid marker and [14C] glycerol trioleate as the test lipid. Percentage absorption of triolein is calculated from the isotope ratio ingested and excreted in faeces. Absorption in 25 normal subjects ranged from 96.4-100% (mean 98.6, S.D. +- 1.15). In 24 patients with known pancreatic or small intestinal disease and steatorrhoea absorption ranged from 0.01% to 89.9%. The test has also been assessed by comparison with a standard Lundh test and faecal fat estimation in 34 patients. (Auth.)

  7. Over-estimation of glucose-6-phosphatase activity in brain in vivo. Apparent difference in rates of [2-3H]glucose and [U-14C]glucose utilization is due to contamination of precursor pool with 14C-labeled products and incomplete recovery of 14C-labeled metabolites.

    Dienel, G A; Nelson, T; Cruz, N F; Jay, T; Crane, A M; Sokoloff, L

    1988-12-25

    Significant dephosphorylation of glucose 6-phosphate due to glucose-6-phosphatase activity in rat brain in vivo was recently reported (Huang, M., and Veech, R.L. (1982) J. Biol. Chem. 257, 11358-11363). The evidence was an apparent more rapid 3H than 14C loss from the glucose pool and faster [2-3H]glucose than [U-14C]glucose utilization following pulse labeling of the brain with [2-3H,U-14C]glucose. Radiochemical purity of the glucose and quantitative recovery of the labeled products of glucose metabolism isolated from the brain were obviously essential requirements of their study, but no evidence for purity and recovery was provided. When we repeated these experiments with the described isolation procedures, we replicated the results, but found that: 1) the precursor glucose pool contained detritiated, 14C-labeled contaminants arising from glucose metabolism, particularly 2-pyrrolidone-5-carboxylic acid derived from [14C]glutamine; 2) [14C]glucose metabolite were not quantitatively recovered; 3) the procedure used to isolate the glucose itself produced detritiated, 14C-labeled derivatives of [2-3H,U-14C]glucose. These deficiencies in the isolation procedures could fully account for the observations that were interpreted as evidence of significant glucose 6-phosphate dephosphorylation by glucose-6-phosphatase activity. When glucose was isolated by more rigorous procedures and its purity verified in the present studies, no evidence for such activity in rat brain was found. PMID:2848837

  8. Internal dosimetry of a chylomicron-like emulsion doubly-labeled with 3H-TG and {sup 14}C-CE in humans

    Marcato, Larissa A.; Carvalho, Diego V.S.; Santos, Robinson A.; Hamada, Margarida M.; Mesquita, Carlos H. de [Energy and Nuclear Research Institute (IPEN/CNEN/SP), Sao Paulo, SP (Brazil); Vinagre, Carmen [University of Sao Paulo, SP (Brazil). The Heart Institute of the Medical School Hospital; Maranhao, Raul C. [University of Sao Paulo, SP (Brazil). Faculty of Pharmaceutical Sciences

    2010-07-01

    Full text: This paper describes a research about the calculation of the effective equivalent doses to which participants are exposed when submitted to studies that use artificial lipid emulsions doubly-labeled with radioactive tracers {sup 14}C and {sup 3}H. Several studies have used these emulsions in order to improve the knowledge of the biodistribution parameters of plasma lipoproteins. In the particular case of studies with chylomicron-like emulsion doubly- labeled with radioactive cholesteryl esters ({sup 14}C-CE) and triacylglycerols ({sup 3}H-TG) the dosimetric calculations was estimated indirectly. Initially, the LIA limits suggested by ICRP no 26 for {sup 3}H and {sup 14}C were used, however the LIA parameter is dependent on the chemical form of the labeled product and these parameters have not been scheduled yet for artificial lipoproteins. In particular for the {sup 14}C-CE, the internal dose in humans was estimated from the allometric theory using data from the biodistribution in rats with approximately 0.4 kg. The purpose of this paper is to improve the estimation of the effective equivalent dose in humans in order to contribute to future studies that will utilize artificial lipoproteins. For this study, chylomicron-like emulsion containing radioactive lipids were injected intravenously in bolus into the volunteers and aliquots of blood were collected at predetermined intervals of time. The activity of each aliquot was measured in liquid scintillator using a spectrometer. The plasmatic radioactive decay curves were determined and subsequently the kinetic parameters and effective equivalent doses were calculated using the ANACOMP software. It was proposed a kinetic model consisting of eight compartments for the biodistribution of plasma lipoproteins in humans. (author)

  9. Underestimation of glucose turnover measured with [6-3H]- and [6,6-2H]- but not [6-14C]glucose during hyperinsulinemia in humans

    Recent studies indicate that hydrogen-labeled glucose tracers underestimate glucose turnover in humans under conditions of high flux. The cause of this underestimation is unknown. To determine whether the error is time-, pool-, model-, or insulin-dependent, glucose turnover was measured simultaneously with [6-3H]-, [6,6-2H2]-, and [6-14C]glucose during a 7-h infusion of either insulin (1 mU.kg-1.min-1) or saline. During the insulin infusion, steady-state glucose turnover measured with both [6-3H]glucose (8.0 +/- 0.5 mg.kg-1.min-1) and [6,6-2H2]glucose (7.6 +/- 0.5 mg.kg-1.min-1) was lower (P less than .01) than either the glucose infusion rate required to maintain euglycemia (9.8 +/- 0.7 mg.kg-1.min-1) or glucose turnover determined with [6-14C]glucose and corrected for Cori cycle activity (9.8 +/- 0.7 mg.kg-1.min-1). Consequently negative glucose production rates (P less than .01) were obtained with either [6-3H]- or [6,6-2H2]- but not [6-14C]glucose. The difference between turnover estimated with [6-3H]glucose and actual glucose disposal (or 14C glucose flux) did not decrease with time and was not dependent on duration of isotope infusion. During saline infusion, estimates of glucose turnover were similar regardless of the glucose tracer used. High-performance liquid chromatography of the radioactive glucose tracer and plasma revealed the presence of a tritiated nonglucose contaminant. Although the contaminant represented only 1.5% of the radioactivity in the [6-3H]glucose infusate, its clearance was 10-fold less (P less than .001) than that of [6-3H]glucose. This resulted in accumulation in plasma, with the contaminant accounting for 16.6 +/- 2.09 and 10.8 +/- 0.9% of what customarily is assumed to be plasma glucose radioactivity during the insulin or saline infusion, respectively (P less than .01)

  10. Co-permeability of 3H-labeled water and 14C-labeled organic acids across isolated plant cuticles. Investigating cuticular paths of diffusion and predicting cuticular transpiration

    Penetration of 3H-labeled water (3H2O) and the 14C-labeled organic acids benzoic acid ([14C]BA), salicylic acid ([14C]SA), and 2,4-dichlorophenoxyacetic acid ([14C]2,4-D) were measured simultaneously in isolated cuticular membranes of Prunus laurocerasus L., Ginkgo biloba L., and Juglans regia L. For each of the three pairs of compounds (3H2O/[14C]BA, 3H2O/[14C]SA, and 3H2O/[14C]2,4-D) rates of cuticular water penetration were highly correlated with the rates of penetration of the organic acids. Therefore, water and organic acids penetrated the cuticles by the same routes. With the combination 3H2O/[14C]BA, co-permeability was measured with isolated cuticles of nine other plant species. Permeances of 3H2O of all 12 investigated species were highly correlated with the permeances of [14C]BA (r2 = 0.95). Thus, cuticular transpiration can be predicted from BA permeance. The application of this experimental method, together with the established prediction equation, offers the opportunity to answer several important questions about cuticular transport physiology in future investigations

  11. Absorption of 14C-stearic acid and 3H-palmitic acid from the intestines of a re-entrant cannulated sheep

    A sheep fitted with a rumen cannula, a simple cannula at the proximal end and a re-entrant cannula at the ileal end of the duodenum, was fed with a normal diet of hay and concentrate. Chromic oxide impregnated on paper and equivalent to 1.5 g, was daily pushed through the rumen during the preliminary feeding period. On the day of the experiment, a mixture of 3H-methyl palmitate and 14C-methyl stearate was introduced into the rumen and the samples of blood, digesta from rumen, upper and lower cannulae were collected at 3 h intervals over a period of 36 hours. The 3H and 14C specific activity time curves of palmitic, stearic and total fatty acids showed a sort of precursor product relationship, in the order of rumen upper and lower cannula, but such a curve for serum lipoprotein fatty acids gave two to three peaks. The percentage absorption between upper and lower cannula was 83.5 for total fatty acids, 85.4 for palmitic acid and 85.2 for stearic acid. (author)

  12. Metabolism of 3H- and 14C-labeled glutamate, proline, and alanine in normal and adrenalectomized rats using different sites of tracer administration and sampling.

    Said, H M; Chenoweth, M; Dunn, A

    1989-08-01

    Alanine, glutamate and proline labeled with 14C and 3H were infused into fasted normal and adrenalectomized rats. Alanine was administered by the A-V mode (arterial administration-venous sampling), and glutamate and proline by both the A-V and V-A (venous administration-arterial sampling) modes. The kinetics of 14C alanine and 14C glutamate differed markedly from those of the tritium-labeled compounds, but there was little difference in the kinetics of 3H and 14C proline. The replacement rate calculated from the A-V mode for glutamate was about half that obtained in the V-A mode, but there was little difference with proline. The masses of the amino acids (total content of amino acids in the body) were calculated from the washout curves of the tritium-labeled compounds after the infusion of tracer was terminated. The masses for the normal rats were 407 mumol/kg for alanine, 578 mumol/kg for glutamate and 296 mumol/kg for proline. The so-called distribution spaces calculated conventionally from total masses and the amino acid concentrations in plasma are much greater than the volume of the body, reflecting the fact that amino acid concentrations in tissues greatly exceed those in plasma. Adrenalectomy markedly affected the kinetics of the three amino acids, and their replacement rates were greatly reduced. The proline and glutamate masses were reduced by at least one half, while that of alanine was unchanged. Adrenalectomy markedly reduced the conversion of proline to glutamate. The hydrocortisone regimen used in this study restored the metabolism of alanine and glutamate to normal, but had no effect on that of proline. PMID:2569659

  13. Effect of hypoxia on the incorporation of [2-3H] glycerol and [1-14C[-palmitate into lipids of various brain regions

    The lipid metabolism in guinea pig brain after intermittent hypoxia, prolonged for 80 hrs, was markedly impaired. The in vivo incorporation of [2-3H] glycerol and [1-14C] palmitate into lipids of microsomes, mitochondria, myelin, and synaptosomes, purified form cerebral hemispheres, was significantly lower in the hypoxic animals than in the controls. The same effect was observed on the incorporation of labeled precursors into lipids of mitochondria purified from cerebellum and brainstem. In particular, the labeling of th major phospholipids present - ie, phosphatidylcholine (PC) and phosphatidylethanolamine (PE) - in the mitochondria of the three brain regions examined decreased after hypoxic treatment

  14. Metabolism of [4-14C]progesterone and [7-3H]pregnenolone by human ovaries perfused in vitro

    Nine human ovaries were perfused in vitro with [4-14C]progesterone and in addition one ovary with [7-3H]pregnenolone. From the perfusate unchanged progesterone and five different metabolites were isolated: 20αdihydroprogesterone, 17α-hydroxyprogesterone, 16α-hydroxyprogesterone, 5α-pregnane-3,20-dione and 4-androstene-3,17-dione. In the ovarian tissue saturated pregnane derivatives were the main metabolites. When α3Hωpregnenolone and α14Cωprogesterone were perfused simultaneously a stimulation of deltasub(4-5)-isomerase and 3β-dehydrogenase activity by HCG was demonstrated. (author)

  15. Degradation in vitro of [3H]lysine and [14C]leucine-labelled protein by proteases from developing normal and opaque-2 Zea mays endosperm

    During later stages of kernel development total lysine content per endosperm in normal and opaque-2 maize endosperms decreased in spite of net increase in total protein. The proteolytic enzymes increased during development until 25 d after pollination and later declined in both normal and opaque-2 endosperms. Release of lysine in vitro from [3H]lysine and [14C]leucine-labelled normal maize endosperm proteins by proteases from developing normal maize endosperms was higher than in opaque-2 endosperms towards later stages of maturity. Present study suggests that lysine-liberating proteases present in endosperms also contribute to decrease in lysine and consequently the quality of protein. (author)

  16. Labelling of glycerolipids in the cotyledons of developing oilseeds by [1-14C] acetate and brace2-3H] glycerol

    3-sn-Phosphatidylcholine was identified as the major lipid in cotyledons from the developing seeds of soya bean, linseed and safflower when tissue was steamed before lipid extraction. Incubation for up to 3h changed the composition of this lipid and of diacylglycerol. Labelling studies, including pulse-chase experiments, were carried out with [1-14C] acetate and [2-3H] glycerol supplied to detached cotyledons. The results suggest a rapid turnover of 3-sn-phosphatidylcholine during triacylglycerol accumu-lation in developing oilseeds, and are consistent with the operation of a biosynthetic route whereby oleate initially esterified to the phospholipid is first desaturated, then polyunsaturated fatty acids transferred to triacylglycerol, via diacylglycerol. The possible role of oleoyl phosphatidylcholine as a substrate for oleate desaturation is discussed. (author)

  17. Glucose turnover in kelp bass (Paralabrax sp.): in vivo studies with [6-3H,6-14C]glucose

    [6-3H,6-14C]glucose was injected via an indwelling arterial cannula in free-swimming, fed, and fasted kelp bass to determine hepatic glucose production, peripheral glucose uptake, minimal glucose mass, mean transit time, and the percent of carbon recycling under the two different nutritional states. Mean plasma glucose levels remained unchanged in fed and fasted fish (48 +- 8 vs. 43 +- 8 mg/100 ml). During steady-state conditions, glucose replacement rates of fed and fasted fish determined with [6-3H]glucose are similar (0.035 +- 0.006 vs. 0.025 +- 0.003 mg/min per 100 g) and do not differ from rates determined with [6-14C]glucose (0.035 +- 0.005 vs. 0.026 +- 0.002). The minimal glucose masses and the mean transit times determined with both isotopes are also similar suggesting that plasma glucose levels and glucose turnover are maintained in fish fasted up to 40 days with no apparent increase in carbon recycling. Nonsteady-state isotope experiments suggest that these fish can alter rates of hepatic glucose production and peripheral uptake in response to hyper- and hypoglycemia

  18. The synthesis of taurine-conjugated bile acids and bile acid sulfates labeled with 14C or 3H in the taurine moiety

    Studies of bile acid transport systems require radio-labeled taurine-conjugated bile acids with high specific activity. An established procedure was optimized to provide mild, fast, and effective conjugation of radio-labeled taurine with different types of bile acids, including those with labile 7α-hydroxy-3-oxo-Δ4 or 3β, 7α-dihydroxy-Δ5 structures. Taurine labeled with 14C or 3H was reacted with excess bile acid anhydride formed from the tributylamine salt and ethylchloroformate (2/1 M/M) in aqueous dioxane for 15 min at room temperature. The yields were higher than 95% and less than 2% side products were formed. Bile acid sulfates were conjugated with 14C- or 3H-labeled taurine by using N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline as the coupling reagent. The products were effectively purified by chromatography of the sodium salts on Sephadex LH-20. The yields of taurine-conjugated bile acid sulfates were 65-70%. (author)

  19. Determination of Carbon-14 (14C) and Tritium (3H) in the graphite thermal column of a IRT-2000 research reactor in Sofia

    Radiocarbon has average, and tritium has low level of radiotoxicity, but both are easily absorbable radionuclide from the body as due to their chemical nature they are included in almost all the chemical compounds involved in metabolic chains and in structure of proteins and biological macromolecules. Due to above mentioned reasons, the analysis and determination of these two major radionuclides is very significant for radiation protection for both the public and the environment as well as for occupational exposure of personnel. This publication describes the detailed procedure for determining the concentration of 3H and 14C in samples selected at the stage 'partial dismantling' of the research nuclear reactor IRT-2000 reconstruction. The procedure consists graphite sample thermal burning in the tubing muffle furnace at a maximum temperature of 850'0C. After combustion the gas mixture passes through a CuO catalyst, heated to 450-5000C and through a series of traps for 3H and 14C capturing. The captured CO2+ 14CO2 as Na2CO3 in NaOH precipitates with BaCl2 as BaCO3 and it is followed by a liquid scintillation spectrometry measurements

  20. A multi-isotope (B, Sr, O, H) and age dating (3H-3He, 14C) study of groundwater from Salinas Valley, California

    This study investigates the chemical and isotopic compositions of groundwater from Salinas Valley, California in order to constrain the origin and rates of groundwater contamination. We use an array of geochemical, environmental isotopes of water (18O/16O, D/H, 3H-3He) and dissolved salts (11B/10B, 87Sr/86Sr, 14C) to establish a reliable conceptual model for the basin. The basin consists of a deep, confined '400-foot aquifer' overlying the '180-foot aquifer' and a perched aquifer, all made up of sand, gravels, clays, and alluvial deposits. Our 3H-3He, 14C, and δ18O results show different replenishment zones and rates in the basin: (1) rapid replenishment (14C concentrations of 72 to 98 pmc) in the perched and 180-foot aquifers in the northern area; (2) fast arrival (15 years) of 18O- and NO3-enriched agriculture-return flows in the unconfined 180-foot aquifer in the central valley; (3) young water recharge (6 to 20 years) fi-om the Salinas River, which is enriched in 18O and D relative to GMWL, occurs in the southern basin; and (4) travel time of >10,000 years (14C = 21.3 PMC) in the deep 400-foot aquifer in the northern area of the valley, indicating pristine slow recharge. We identified several different end-member saline components with distinguishable chemical and isotopic fingerprints: (1) agriculture return flow in the perched aquifer (e.g., high NO3 and SO4, low 87Sr/86Sr 0.7082, δ11B = 19 per mille); (2) salt-water intrusion in the northern basin (e.g., low Na/Cl, marine Br/Cl, high Ca/Mg, δ11B = 17 to 38 per mille, 87Sr/86Sr = 0.7088 to 0.7096; (3) non-marine saline water in the southern part of the valley (e.g., high SO4, high Na/Cl, δ11B = 24 to 30 per mille, 87Sr/86Sr = 0.70852). The geochemical and isotopic fingerprints of the different water sources enables us to delineate the impact of these sources in different areas of the valley as well as to evaluate the origin of the saline, Sod-enriched plume, that is located north of Salinas City Our data

  1. [4,5-3H]lysine:[14C]lysine dual-label method to measure lysine hydroxylation in collagen

    A new method has been developed to determine the extent of lysine hydroxylation in newly synthesized collagen. This method relies on the measurement of changes in the ratio of [3H]lysine:[14C]lysine in collagenase digests, resulting from loss of tritium from the C-5 position of lysine during hydroxylation. Lysine hydroxylation can be measured in the presence of large amounts of noncollagen proteins, and simultaneous quantitation of the relative rates of collagen and non-collagen protein production is obtained. The dual-label lysine method is simple, rapid, and accurate. There was a very good correlation between this method and column chromatography procedures currently used for the measurement of lysine hydroxylation

  2. Problems occurring while carrying out cost-benefit analysis for 3H, 14C, 85Kr, iodine and aerosols in nuclear facilities

    Up to now the retention of radioactive material for nuclear facilities has been based on the maximum individual dose. The maximum individual dose can locally be lowered considerably by higher dissolution. In general, the collective doses are not lowered by this. In order to set up regulations concerning collective doses, the new recommmendations of the ICRP are very welcome. However, the costs of detriment and the period to be considered have not yet been defined. Therefore there are no fixed methods for carrying out a cost-benefit analysis. Furthermore, for nuclear technology the costs and the effectiveness of the retention of radioactive material for non-realized facilities can only be quoted roughly, which makes a cost-benefit analysis more difficult. A cost-benefit analysis for the retention of radioactive material in nuclear power plants with LWRs and reprocessing plants of the PUREX process has been carried out with best estimate data. The results show that the development of further retention facilities for nuclear power plants is not justifiable except possibly for a 14C retention with a decontamination factor (DF) of 2 to 4. For reprocessing plants 3H should be retained with a DF of 6, 14C with a factor of about 20, 129I with a factor of about 200 and the aerosols with a factor of about 109. Whether 85Kr should be retained after a cost-benefit analysis depends on the applied costs of detriment. For 200 US dollar/man.rem 85Kr should be retained with a DF of 100. Nearly the same result occurs, if 2x107 Ci 85Kr per year get into the reprocessing plant instead of 1.2x107 Ci 85Kr per year as assumed here and costs of detriment of 100 dollar/man.rem. The problems occurring while carrying out the cost-benefit analysis are discussed. (author)

  3. Single-injection method for evaluation of renal function with 14C-inulin and 3H-tetraethylammonium bromide in dogs and cats

    A double-isotope single-injection method without urine collection for the estimation of glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) in dogs and cats was evaluated. The GFR was determined, using 14C-inulin and ERPF was determined, using [3H]tetraethylammonium bromide. Using a modified single exponential, 1-compartment mathematical model, the renal clearance of these solutes was estimated with a plasma radioactivity disappearance curve constructed from samples collected over a 150-minute time period. In 25 dogs, GFR, ERPF, and filtration fraction were 3.55 +/- 0.14 ml/kg/min, 10.51 +/- 0.72 ml/kg/min, and 0.34 +/- 0.02, respectively. In 25 cats, GFR, ERPF, and filtration fraction were 3.24 +/- 0.14 ml/kg/min, 8.14 +/- 0.53 ml/kg/min, and 0.39 +/- 0.02, respectively. This time-efficient and reliable method, using beta-emitting isotopes, yielded renal functional values well within the normal ranges reported by a variety of other isotopic and nonisotopic procedures. The advantages of the present procedure over previous double-isotope single-injection methods include the use of less costly, lower energy-using, and less penetrating beta emittors, as well as a shortened blood sampling schedule

  4. Effect of hypoxia on the uptake of [methyl-3H]choline, [1-14C] acetate and [18F]FDG in cultured prostate cancer cells

    Introduction: Choline, acetate and glucose ([2-18F]fluoro-2-deoxyglucose, [18F]FDG) analogs are under investigation as positron emission tomography (PET) tracers for the imaging of prostate cancer; however, their response to tumor hypoxia has not been clarified. Methods: The uptake of [methyl-3H]choline, [1-14C]acetate and [18F]FDG was monitored in androgen-independent PC-3 cells and androgen-sensitive LNCaP cells under aerobic or anoxic conditions. The effect of androgen depletion was also examined. Results: PC-3 cells exhibited aerobic choline and acetate uptake five to six times higher than FDG uptake, whereas LNCaP cells showed choline uptake 2.2-fold higher than acetate uptake and 10-fold higher than FDG uptake. After 4 h of anoxia, PC-3 cells showed an 85% increase in FDG uptake, a 15% decrease in choline uptake and a 36% increase in acetate uptake, whereas LNCaP cells showed a 212% increase in FDG uptake, a 28% decrease in choline uptake and no change in acetate uptake. Androgen depletion resulted in a marked decrease in the uptake of all tracers in LNCaP cells but no changes in PC-3 cells. Conclusion: In aerobic conditions, both PC-3 and LNCaP cells exhibited an order of uptake preference as follows: choline>acetate>FDG. In hypoxic cells, the order is reversed, reflecting diverse biochemical responses to hypoxia. These findings may help to explain PET imaging findings of the diverse responses of these tracers in different stages and locations of prostate cancer. Androgen depletion markedly suppressed the uptake of all three tracers in LNCaP cells, which suggests the potential for underestimation of the disease state when PET imaging is performed subsequent to antiandrogen therapy

  5. Using 14C and 3H to delineate a recharge 'window' into the Perth Basin aquifers, North Gnangara groundwater system, Western Australia.

    Meredith, Karina; Cendón, Dioni I; Pigois, Jon-Philippe; Hollins, Suzanne; Jacobsen, Geraldine

    2012-01-01

    The Gnangara Mound and the underlying Perth Basin aquifers are the largest source of groundwater for the southwest of Australia, supplying between 35 and 50% of Perth's potable water (2009-2010). However, declining health of wetlands on the Mound coupled with the reduction in groundwater levels from increased irrigation demands and drier climatic conditions means this resource is experiencing increased pressures. The northern Gnangara is an area where the Yarragadee aquifer occurs at shallow depths (~50 m) and is in direct contact with the superficial aquifer, suggesting the possibility of direct recharge into a generally confined aquifer. Environmental isotopes ((14)C and (3)H) and hydrochemical modelling were used to assess the presence of a recharge 'window' as well as understand the groundwater residence time within different aquifers. Forty-nine groundwater samples were collected from depths ranging from 11 to 311 m below ground surface. The isotopic variation observed in the superficial aquifer was found to be controlled by the different lithologies present, i.e. quartz-rich Bassendean Sand and carbonate-rich sediments of the Ascot Formation. Rainfall recharge into the Bassendean Sand inherits its dissolved inorganic carbon from the soil CO(2). Organic matter throughout the soil profile is degraded by oxidation leading to anoxic/acidic groundwater, which if in contact with the Ascot Formation leads to enhanced dissolution of carbonates. Hydrochemical mass balance modelling showed that carbonate dissolution could contribute 1-2 mmol kg(-1) of carbon to groundwaters recharged through the Ascot Formation. The corrected groundwater residence times of the Yarragadee aquifer in the northern part of the study area ranged from 23 to 35 ka, while waters in the southeastern corner ranged from sub-modern to 2 ka. Groundwater ages increase with distance radiating from the recharge 'window'. This study delineates a recharge 'window' into the commonly presumed confined

  6. Stereochemical determination of carbon partitioning between photosynthesis and photorespiration in C3 plants: use of (3R)-D-[3-3H1, 3-14C]glyceric acid

    When (3R)-D-[3-3H1,3-14C]glyceric acid is supplied in tracer amounts to illuminated tobacco leaf discs, the acid penetrates to the chloroplasts without loss of 3H, and is phosphorylated there. Subsequent metabolism associated with the reductive photosynthetic cycle fully conserves 3H. Oxidation of ribulose bisphosphate (RuBP) by RuBP carboxylase-oxygenase (EC 4.1.1.39) results in the formation of (2R)-[2-3H1, 14C]glycolic acid which, on oxidation by glycolate oxidase (EC 1.1.3.1), releases 3H to water. Loss of 3H from the combined photosynthetic and photorespiratory systems is, therefore, associated with the oxidative photorespiratory loop. Assuming steady-state conditions and a basic metabolic model, the fraction of RuBP oxidized and the photorespiratory carbon flux relative to gross or net CO2 fixation can be calculated from the fraction of supplied 3H retained in the triose phosphates exported from the chloroplasts. This retention can be determined from the 3H:14C ratio for glucose obtained from isolated sucrose. The dependence of 3H retention upon O2 and CO2 concentrations can be deduced by assuming simple competitive kinetics for RuBP carboxylase-oxygenase. The experimental results confirmed the stereochemical assumptions made. Under conditions of negligible photorespiration 3H retention was essentially complete. The change in 3H retention with O2 and CO2 concentrations were investigated. For leaf discs (upper surface up) in normal air, it was estimated that 39% of the RuBP was oxidized, 32% of the fixed CO2 was photorespired, and the photorespiration rate was 46% of the net photosynthetic CO2 fixation rate. These are minimal estimates, as it is assumed that the only source of photorespired CO2 is glycine decarboxylation

  7. Using 14C and 3H to delineate a recharge ‘window’ into the Perth Basin aquifers, North Gnangara groundwater system, Western Australia

    The Gnangara Mound and the underlying Perth Basin aquifers are the largest source of groundwater for the southwest of Australia, supplying between 35 and 50% of Perth's potable water (2009–2010). However, declining health of wetlands on the Mound coupled with the reduction in groundwater levels from increased irrigation demands and drier climatic conditions means this resource is experiencing increased pressures. The northern Gnangara is an area where the Yarragadee aquifer occurs at shallow depths (∼ 50 m) and is in direct contact with the superficial aquifer, suggesting the possibility of direct recharge into a generally confined aquifer. Environmental isotopes (14C and 3H) and hydrochemical modelling were used to assess the presence of a recharge ‘window’ as well as understand the groundwater residence time within different aquifers. Forty-nine groundwater samples were collected from depths ranging from 11 to 311 m below ground surface. The isotopic variation observed in the superficial aquifer was found to be controlled by the different lithologies present, i.e. quartz-rich Bassendean Sand and carbonate-rich sediments of the Ascot Formation. Rainfall recharge into the Bassendean Sand inherits its dissolved inorganic carbon from the soil CO2. Organic matter throughout the soil profile is degraded by oxidation leading to anoxic/acidic groundwater, which if in contact with the Ascot Formation leads to enhanced dissolution of carbonates. Hydrochemical mass balance modelling showed that carbonate dissolution could contribute 1–2 mmol kg−1 of carbon to groundwaters recharged through the Ascot Formation. The corrected groundwater residence times of the Yarragadee aquifer in the northern part of the study area ranged from 23 to 35 ka, while waters in the southeastern corner ranged from sub-modern to 2 ka. Groundwater ages increase with distance radiating from the recharge ‘window’. This study delineates a recharge ‘window’ into the commonly presumed

  8. Using {sup 14}C and {sup 3}H to delineate a recharge 'window' into the Perth Basin aquifers, North Gnangara groundwater system, Western Australia

    Meredith, Karina, E-mail: kmj@ansto.gov.au [Australian Nuclear Science and Technology Organisation, Institute for Environmental Research, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia); Cendon, Dioni I. [Australian Nuclear Science and Technology Organisation, Institute for Environmental Research, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia); Pigois, Jon-Philippe [Department of Water, PO Box K822 Perth WA 6842 (Australia); Hollins, Suzanne; Jacobsen, Geraldine [Australian Nuclear Science and Technology Organisation, Institute for Environmental Research, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia)

    2012-01-01

    The Gnangara Mound and the underlying Perth Basin aquifers are the largest source of groundwater for the southwest of Australia, supplying between 35 and 50% of Perth's potable water (2009-2010). However, declining health of wetlands on the Mound coupled with the reduction in groundwater levels from increased irrigation demands and drier climatic conditions means this resource is experiencing increased pressures. The northern Gnangara is an area where the Yarragadee aquifer occurs at shallow depths ({approx} 50 m) and is in direct contact with the superficial aquifer, suggesting the possibility of direct recharge into a generally confined aquifer. Environmental isotopes ({sup 14}C and {sup 3}H) and hydrochemical modelling were used to assess the presence of a recharge 'window' as well as understand the groundwater residence time within different aquifers. Forty-nine groundwater samples were collected from depths ranging from 11 to 311 m below ground surface. The isotopic variation observed in the superficial aquifer was found to be controlled by the different lithologies present, i.e. quartz-rich Bassendean Sand and carbonate-rich sediments of the Ascot Formation. Rainfall recharge into the Bassendean Sand inherits its dissolved inorganic carbon from the soil CO{sub 2}. Organic matter throughout the soil profile is degraded by oxidation leading to anoxic/acidic groundwater, which if in contact with the Ascot Formation leads to enhanced dissolution of carbonates. Hydrochemical mass balance modelling showed that carbonate dissolution could contribute 1-2 mmol kg{sup -1} of carbon to groundwaters recharged through the Ascot Formation. The corrected groundwater residence times of the Yarragadee aquifer in the northern part of the study area ranged from 23 to 35 ka, while waters in the southeastern corner ranged from sub-modern to 2 ka. Groundwater ages increase with distance radiating from the recharge 'window'. This study delineates a recharge

  9. Synthesis of (3,5-/sup 14/C)trachelanthamidine and (5-/sup 3/H)isoretronecanol and their incorporation into the retronecine moiety of riddelliine in Senecio riddellii

    Leete, E.; Rana, J.

    1986-09-01

    (+/-)-(3,5-/sup 14/C)Trachelanthamidine and (+/-)-(5-/sup 3/H)isoretronecanol, which are diastereomers, were prepared from potassium (/sup 14/C)cyanide and (5-/sup 3/H)proline, respectively. These compounds and (1,4-/sup 14/C)putrescine were administered to Senecio riddellii plants resulting in the formation of labeled riddelliine, in which almost all the radioactivity was located in its retronecine moiety. The activity of the beta-alanine obtained by degradation of the retronecine was consistent with specific labeling of this pyrrolizidine base at the expected positions. The extremely high absolute incorporation (15.1, 22.1%) of trachelanthamidine into riddelliine strongly favors this 1-hydroxymethylpyrrolizidine as the one on the main biosynthetic pathway to retronecine. The lower incorporation (0.75%) of isoretronecanol may represent a minor or aberrant pathway to retronecine.

  10. Role of leucine in isoprenoid metabolism. Incorporation of (3-/sup 13/C)leucine and of (2-/sup 3/H,4-/sup 14/C)-. beta. ,. beta. -dimethyl-acrylic acid into phytosterols by tissue cultures of Andrographis paniculata

    Anastasis, P.; Freer, I.; Overton, K.; Rycroft, D.; Singh, S.B. (Glasgow Univ. (UK). Dept. of Chemistry)

    1985-02-01

    (3-/sup 13/C)Leucine is incorporated into phytosterols by tissue cultures of Andrographis paniculata by breakdown to acetyl-CoA and its subsequent incorporation via (3S)-3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) and mevalonic acid; (2-/sup 3/H,4-/sup 14/C)-..beta..,..beta..-dimethylacrylic acid also is not incorporated intact.

  11. Use of radioactive glucosamine in the perfused rat liver to prepare α1-acid glycoprotein (orosomucoid) with 3H- or 14C-labelled sialic acid and N-acetylglucosamine residues

    A method was developed whereby [1-14C]glucosamine was used in a perfused rat liver system to prepare over 2 mg of α1-acid glycoprotein with highly radioactive sialic acid and glucosamine residues. The liver secreted radioactive α1-acid glycoprotein over a 4-6 h period, and this glycoprotein was purified from the perfusate by chromatography on DEAE-cellulose at pH3.6. The sialic acid on the isolated glycoprotein had a specific radioactivity of 3.1 Ci/mol, whereas the glucosamine-specific radioactivity was 4.3 Ci/mole. The latter amino-sugar residues on the isolated protein were only 13-fold less radioactive than the initially added [1-14C]glucosamine. Orosomucoid with a specific radioactivity of 31.3 μCi/mg of protein was obtainable by using [6-3H]glucosamine. Many other radioactive glycoproteins were found to be secreted into the perfusate by the liver. Thus this experimental system should prove useful for obtaining other serum glycoproteins with highly radioactive sugar moieties. (author)

  12. A Multi-Isotope (B, Sr, O, H, C) and Age Dating (3H-3He, 14C) Study of Ground Water From Salinas Valley, California: Hydrochemistry, Dynamics, and Contamination Processes

    Vengosh, A; Gill, J; Davisson, M L; Hudson, B G

    2001-08-01

    The chemical and isotopic ({sup 11}B/{sup 10}B, {sup 87}Sr/{sup 86}Sr, {sup 18}O/{sup 16}O, {sup 2}H/H, {sup 13}C/{sup 12}C, {sup 14}C, {sup 3}He/{sup 3}H) compositions of groundwater from the upper aquifer system of the Salinas Valley in coastal central California were investigated in order to delineate the origin and processes of groundwater contamination in this complex system. The Salinas Valley has a relatively deep, confined ''400-foot'' aquifer, overlain by a ''180-foot'' aquifer, and a shallower perched aquifer, all made up of alluvial sand, gravel, and clay deposits. Groundwater from the aquifers have different {sup 14}C ages; fossil ({sup 14}C = 21.3 pmc) for the 400-foot, and modern ({sup 14}C = 72.2 to 98.2 pmc) for the 180-foot. Fresh groundwater in all aquifers is recharged naturally and artificially and through the Salinas River. The two modes of recharge can be distinguished chemically. We identified several different saline components with distinguishable chemical and isotopic fingerprints. (1) Salt-water intrusion in the northern basin has Cl concentrations up to 1700 mg/l, a Na/Cl ratio seawater, {delta}{sup 11}B between +17 and +38 per mil, and {sup 87}Sr/{sup 86}Sr between 0.7088 and 0.7096. Excess dissolved Ca, relative to the expected concentration for simple dilution of seawater, correlates with {sup 87}Sr/{sup 86}Sr ratios, suggesting base exchange reaction with clay minerals. (2) Agriculture return flow is high in NO{sub 3} and SO{sub 4}, with a {sup 87}Sr/{sup 86}Sr = 0.7082, {delta}{sup 11}B = 19 per mil; and {delta}{sup 13}C between -23 and -17 per mil. The {sup 3}H-{sup 3}He ages (5-17 years) and {sup 14}C data suggest vertical infiltration rates of irrigation water of 3 to 10 m/yr. (3) Non-marine saline water in the southern part of the valley has high TDS up to 3800 mg/l, high SO{sub 4}, Na/Cl ratio >1, {delta}{sup 11}B between +24 and +30 per

  13. Modelling 14C transfer in terrestrial environments in response to chronic and accidental 14C releases.

    Le Dizès, S.

    2011-01-01

    Concern about the quantity of carbon-14 (14C) released for several decades from nuclear facilities has prompted several modelling approaches of 14C behaviour in the environment. The TOCATTA model aims at estimating 14C (and 3H) transfers in terrestrial ecosystems exposed to atmospheric 14C (and 3H) releases from nuclear facilities under normal operating or accidental conditions. The model belongs to the larger framework of the SYMBIOSE modelling and simulation platform that aims at assessing ...

  14. A balance study of /sup 14/C-labelled /sup 3/H-imidazo(4,5-f)quinolin-2-amines (IQ and MeIQ) in rats

    Sjoedin, P.; Jaegerstad, M.

    1984-03-01

    The absorption and excretion of /sup 14/C-labelled 2-amino-3-methylimidazo(4,5-f)quinoline (IQ) and 2-amino-3,4-dimethylimidazo(4,5-f)quinoline (MeIQ) were studied in rats of both sexes. The excretion was rapid and within 24 hr more than 90% of the radioactivity had left the rats. After 72 hr the faecal excretion of both compounds was approximately 45-65% and the corresponding excretion via the urine amounted to 37-49%. Only 1-2% was left in the carcasses and less than 0.2% was found in the expired air. About 70% of the IQ and 80% of the MeIQ was found in the bile fluid in a separate 24-hr study. The two compounds had different biliary excretion patterns and the mutagenicity of the bile correlated closely with the excretion of radioactivity.

  15. Photosynthetic carbon assimilation in C/sub 3/- and C/sub 4/-plants. Tracer experiments using /sup 3/H, /sup 14/C, /sup 13/C and /sup 18/O

    Ohhama, Tamiko (Tokyo Univ. (Japan). Inst. of Applied Microbiology)

    1982-09-01

    The photosynthetic mechanisms of plants have become to be well understood by the use of radioactive and stable isotopes. This review included the distribution of /sup 14/C in photosynthetic intermediates by assimilation with /sup 14/CO/sub 2/, resultant CO/sub 2/ receptors, Calvin cycle, C/sub 4/ photosynthetic pathway, differences between the photosynthetic pathway for C/sub 3/-plants and that for C/sub 4/-plants, photorespiration, glycolate pathway, the yield of photosynthetic quanta and the relationship between assimilation with /sup 14/CO/sub 2/ and /sup 13/C values. Reference was made to the photosynthetic mechanism in /sup 13/C-NMR follow-up with /sup 13/CO/sub 2/.

  16. 2012 Rose Site 32P

    US Fish and Wildlife Service, Department of the Interior — Underwater Site 32P was established off Rose Atoll, American Samoa by Dr. James Maragos, U.S. Fish & Wildlife Service, on August 2, 2004. With a start point...

  17. 2004 Rose Site 32P

    US Fish and Wildlife Service, Department of the Interior — Underwater Site 32P was established off Rose Atoll, American Samoa by Dr. James Maragos, U.S. Fish & Wildlife Service, on August 2, 2004. With a start point...

  18. Natural 14C variations

    This thesis deals with the natural variations in the atmospheric 14C activity, their geophysical origin and their impact on radiocarbon dating. Studies confirm the idea that one is dealing with a mechanism of a certain regularity. The correlation between a 14C variation during the Little Ice Age and the absence of sunspots on the solar surface suggest the sun to be responsible for some kind of modulation of the galactic cosmic ray spectrum. The background of a changing natural 14C level is relevant when studying the antropogenic perturbation of the atmospheric 14C concentration by the addition of CO2 from fossil fuel combustion. The results presented point to a Suess effect over the past 150 years of about 20 per thousand, but also show a local dilution effect. If this local effect is present over large continental parts of the Northern Hemisphere this will put limits to the use of tree ring 14C measurements for testing carbon reservoir models. Finally the influence of 14C variations upon the interpretations of 14C dates for archaeological and geological purposes has been investigated. It is shown that care must be taken especially in the interpretation of highly accurate 14C data of material only covering a few years of growth. One geological example illustrates that 14C variations can easily be interpretated as alternating fast and slow rises of the sea level. (Auth.)

  19. Measurements and hydrological applications of 3H and 14C

    A survey is given on the occurence of T and C14 in the environment and pertinent low-level measuring techniques. T is used as artificial tracer for flow studies in laboratory and field tests. Examples are presented for the use of environmental T and C14 to investigate shallow and deep groundwater and brines, and their interrelation with precipitation and surface water. Problems of sampling of deep groundwater are dealt with. (orig.)

  20. 32P-postlabelling methods for cyclic DNA adducts.

    Watson, W P; Crane, A E; Steiner, S

    1993-01-01

    32P-Postlabelling procedures coupled with HPLC have been developed to detect and measure a range of cyclic DNA adducts formed by bifunctional genotoxic agents. The methods are based on reverse-phase HPLC, particularly column-switching HPLC, to enrich adduct 3'-monophosphates before labelling. Following 3'-dephosphorylation of the 3'5'-[5'-32P]bisphosphates with nuclease P1, the resulting 5'-[32P]monophosphate adducts are resolved, identified and characterized by co-chromatography with synthetic reference standards. The procedures have been applied to a number of cyclic adducts including those formed by chloroacetaldehyde, glycidaldehyde and malonaldehyde. In general, labelling efficiencies measured as chromatographed 5'-[32P]monophosphates were in the range 30-40%. However, the values for the malonaldehyde deoxyguanosine adduct were much lower. The techniques have been applied to studies on the formation of DNA adducts in the skin of male C3H mice treated cutaneously with glycidaldehyde. The HPLC-32P-postlabelling analysis of epidermal DNA hydrolysates indicated that a single major cyclic adduct was formed by reaction with deoxyadenosine residues in mouse skin DNA. The adduct was identified as a hydroxymethyl ethenodeoxyadenosine adduct by comparison with a synthetic standard. This adduct was highly fluorescent and it was possible to make quantitative comparisons of the amounts of adduct determined by either HPLC-32P-postlabelling or HPLC-fluorescence detection. PMID:8225493

  1. The enzymatic preparation of [α-32P]nucleoside triphosphates, cyclic [32P]AMP, and cyclic [32P]GMP

    A method has been developed for the enzymatic preparation of α-32P-labelled ribo- and deoxyribonucleoside triphosphates, cyclic [32P]AMP, and cyclic [32P]GMP of high specific radioactivity and in high yield from 32Psub(i). The method also enables the preparation of [γ-32P]ATP, [γ-32P]GTP, [γ-32P]ITP, and [γ-32P]-dATP of very high specific activity and in high yield. (Auth.)

  2. The remaining percentage of 32P after burning of sulphur tablet containing 32P

    Three types of sulphur tablet containing 32P are made artificially. The remaining percentage of 32P after burning of three types of sulphur tablets containing 32P is 98.1 ± 1.3% for 1st and 2nd types and 97.2 ± 2.8% for 3rd type

  3. Secretin enhances [14C]erythritol clearance in unanesthetized dogs

    To determine the effect of secretin infusion on clearance of inert markers into bile, unanesthetized dogs fitted with Thomas cannulas received continuous infusions of [14C]erythritol and [3H]inulin throughout study. Taurocholic acid administered sequentially at 9.0, 20.0, and 40.0 mumol/min enhanced [14C]erythritol clearance, and GIH secretin (3 units/min) administered along with TCA (40.0 mumol/min) increased [14C]erythritol clearance from 4.9 +/- 1.2 ml/10 min to 6.8 +/- 1.3 ml/10 min (P less than 0.001), but simultaneously measured [3H]inulin clearance was unaltered. Secretin alone also increased [14C]erythritol clearance but did not alter [3H]inulin clearance. The increase in [14C]erythritol clearance per unit increase in bile flow was less during secretin infusion than TCA. Thus, secretin increases [14C]erythritol transport through restricted channels, probably distal to the canaliculi. [14C]Erythritol may not be an accurate marker for canalicular bile flow in dogs during secretin infusion

  4. Synthesis of barbituric acid-2 14C and alloxan-2 14C from urea 14C

    Urea 14C and ethyl malonate have given rise to barbituric acid with a 93 per cent yield. The latter has been converted into its benzylidene derivative with a 81 per cent yield. Oxidation of the latter, by chromic oxide in anhydrous acetic acid provided alloxan-2 14C with 60 per cent yield. Purity of the compounds has been checked by paper chromatography. (author)

  5. The synthesis of [2-3H2] taurine and [2-3H2] hypotaurine

    The synthesis of [2-3H2]-2-aminoethanesulfonate [2-3H]-taurine by the reduction of cyanomethanesulfonic acid with tritium gas is described. The conversion of [2-3H]-taurine and its 14C and 35S isotopic forms to 2-aminoethanesulfinate (hypotaurine) was accomplished by converting taurine to its corresponding sulfonyl chloride and reducing the latter with metallic zinc. (author)

  6. The early history of (32) P as a radioactive tracer in biochemical research: A personal memoir.

    Gest, Howard

    2005-05-01

    The concept of using radioactive isotopes as "tracers" of chemical conversions was conceived and developed by inorganic chemist Georg de Hevesy (Nobel Laureate in Chemistry 1943). In 1935, he began to apply the technique to various biological processes using (32) P, and his experiments revealed the dynamic character of physiology and metabolism. Following de Hevesy's lead, Samuel Ruben (University of California, Berkeley) exploited (32) P in 1937-38 for investigation of phospholipid metabolism. Between 1937 and 1940, Ruben and colleague Martin Kamen spearheaded tracer studies in various biological systems using (32) P, short-lived (11) C, and other radioactive isotopes. During this period, Kamen was responsible for cyclotron-produced radioactive tracers and was able to sustain de Hevesy's research by supplying him with (32) P. In 1940, Ruben and Kamen discovered long-lived (14) C, which later proved to be a very powerful tool for analysis of complex biochemical processes, such as the path of carbon in photosynthesis. Between 1946 and 1950, (32) P was used in studies of bacteriophage replication and photosynthetic metabolism. This memoir surveys the history of these early investigations. PMID:21638569

  7. Spring mobilization of storage /sup 32/P in gingko trees

    Shim, K.K. (City Univ. of Seoul, Korea); Chung, K.H.; Kwon, S.H.

    1978-01-01

    The labelled phosphorus was supplied to the roots of 1-year-old gingko (Gingko biloba L.) trees during dormant period in the glass house and the mobilization of stored /sup 32/P determined in the following early growing season. /sup 32/P was detected in all growing tissues, the level of radioactivity being greatest in the root tissues over the 4-week sampling period. At dormant period, only 0.44% of /sup 32/P was found in storage tissues although the accumulation of /sup 32/P occurred especially in root tissues. During early growing season, /sup 32/P was transported from root tissues to new growing tissues. Eight percent of the initial /sup 32/P in storage tissues was transported to new growing tissues. During the period, the /sup 32/P in the bud tissues increased about 12 fold.

  8. Spring mobilization of storage 32P in gingko trees

    The labelled phosphorus was supplied to the roots of 1-year-old gingko (Gingko biloba L.) trees during dormant period in the glass house and the mobilization of stored 32P determined in the following early growing season. 32P was detected in all growing tissues, the level of radioactivity being greatest in the root tissues over the 4-week sampling period. At dormant period, only 0.44% of 32P was found in storage tissues (bark, wood and bud) although the accumulation of 32P occurred especially in root tissues. During early growing season, 32P was transported from root tissues to new growing tissues (buds). Eight percent of the initial 32P in storage tissues was transported to new growing tissues. During this period, the 32P in the bud tissues increased about 12 fold. (author)

  9. Thermophilic Anaerobic Biodegradation of [14C]Lignin, [14C]Cellulose, and [14C]Lignocellulose Preparations

    Benner, Ronald; Hodson, Robert E.

    1985-01-01

    Thermophilic (55°C) anaerobic enrichment cultures were incubated with [14C-lignin]lignocellulose, [14C-polysaccharide]lignocellulose, and kraft [14C]lignin prepared from slash pine, Pinus elliottii, and 14C-labeled preparations of synthetic lignin and purified cellulose. Significant but low percentages (2 to 4%) of synthetic and natural pine lignin were recovered as labeled methane and carbon dioxide during 60-day incubations, whereas much greater percentages (13 to 23%) of kraft lignin were ...

  10. Development of the new distillation method for 32P production

    32P as a pure β-ray emitter is widely used in nuclear medicine, genetic engineering, biological research, etc. The production process of 32P is mainly based on sulfur distillation after natural 32S(n,p)32P reaction. In this study, a new distillation process for 32P production has been developed and applied for production of 32P. Distillation and condensation of sulfur in the capsule occurred at about 180 .deg. C under 0.1 torr pressure and the distillation rate of sulfur dependened on the temperature of distillation zone. In the typical case, it took 1.5 - 2 hours for the complete distillation of 1 g of sulfur under 0.1 torr pressure and the recovery yield of sulfur was near 100%. Sulfur target in the evacuated capsule was irradiated for 72 hours in HANARO reactor and the fast neutron flux of irradiation hole was 2.8x1014 n/cm2·sec. The irradiated target was distilled at 220 .deg. C and then leached out 32P residue on the capsule surface. The yield of 32P was 8 mCi per 1g of natural sulfur and the qulity analysis of the final product was carried out for radionuclidic purity, radiochemical purity and solid residue. It is expected that the developed process can be useful for production of around 100 mCi 32P and also can be applied to produce 33P using enriched 33S targets

  11. Ultra-low-level measurements of 3H and 14C in wines and champagne

    Scherer, U. W.; Jacobi, M.; Castillo, J.; Förstel, D. H.

    Methods to measure low concentrations of tritium and radiocarbon in wine and champagne, respectively, have been tested by using liquid scintillation counting after chemical sample processing. It could be shown that tritium activity was too low to be measured by our standard low-level liquid scintillation counter, WALLAC Guardian 1414. Positive results could be achieved when using a WALLAC Quantulus. The methods will be established as standard methods to detect forgeries and to improve consumer safety.

  12. Synthesis of carbonyl-14C labelled 'acetochlor'

    Carbonyl-14C labelled 'acetochlor' (2-chloro-N-ethoxymethyl-N-(2-ethyl-6-methylphenyl)acetamide) was prepared by chlorination of acetic-1-14C acid obtained from barium radiocarbonate to monochloroacetic-1-14C acid which was further chlorinated to monochloroacetyl-1-14C chloride. The addition reaction of this latter with 2-ethyl-6-methylene aniline gave a chloromethyl derivative the ethanolysis of which resulted in 'acetochlor' labelled in its carbonyl carbon. The overall radiochemical yield is 51%. (author)

  13. A study of 32P-phosphate uptake in a plant by a real-time RI imaging system

    It is very important to visualize the process of nutrient absorption and distribution to study the physiological activity of the plant. We developed a real-time radioisotope (RI) imaging system, where RI tracers were applied to the plant sample. This system allowed the quantitative measurement concerning the uptake of nutrients labeled with radioisotopes, such as 45Ca, 35S, 32P and 14C as long as several days. The β-rays emitted from the sample were converted to light by a CsI(Tl) scintillator and were guided to a highly sensitive CCD camera. The scintillator surface was covered with an Al plate to avoid LED light penetration but allow selected β-ray penetration. We employed Lotus japonicus for the plant sample and observed the 32P-phosphate absorption in roots and the accumulation to the aboveground part of the plant. The environment condition of daytime and night was simulated by the ON/OFF of LED timer and the accumulation manner of the 32P-phosphate in roots and leaves during daytime and night was analyzed. The accumulation of 32P-phosphate in leaves was highly dependant on light irradiation and higher when the LEDs was turned on, whereas the absorption of 32P-phosphate in root was higher when the LEDs was turned off. The transfer function concerning the transportation of phosphate within the plant during the developmental stage was obtained from the analysis of 32P uptake images. We are now trying to get specific moving images of each radioisotope when two kinds of isotopes, such as 32P and 32S, were applied at the same time to the plant, through an image analysis. (orig.)

  14. Measurement of fecal 14C excretion

    Simultaneous measurements of fecal 14C and expired 14CO2 in the breath are necessary to evaluate patients with various ileal abnormalities and bile salt malabsorption. Following the oral ingestion of the labeled bile acid, glycine-[I-14C]cholic acid, detection of increased fecal 14C without abnormal expiration of 14CO2 identifies patients with ileal resection. This contrasts with the normal fecal 14C content and abnormal expired 14CO2 found in patients with bacterial overgrowth. Fecal 14C content was determined by utilizing Van Slyke combustion of the specimen and trapping the liberated 14CO2 with Scintisorb C. The method is simple, rapid, and accurate, and expands the diagnostic usefulness of the bile salt absorption test

  15. Synthesis of 14C labelled acrylic derivatives: diethyl [3-14C] methylidenemalonate and isobutyl [3-14C] cyanoacrylate

    Isobutyl [3-14C] cyanoacrylate and diethyl [3-14C] methylidenemalonate were synthesized by the intermediate of their protective Diels-Alder adduct with anthracene. These adducts were obtained in a one-pot procedure by Knoevenagel condensation of [14C] paraformaldehyde with isobutyl cyanoacetate and diethyl malonate respectively in the presence of a basic catalyst and anthracene. The adducts are stable crystalline compounds easily purified by recrystallization. The olefinic target compounds were obtained in high chemical and radiochemical purity (>99%) by thermolysis at 2200C in mineral oil in the presence of maleic anhydride. (author)

  16. Incorporation of 14C from [14C]phenylalanine into condensed tannin of sorghum grain

    A procedure is described for obtaining condensed tannin from sorghum [Sorghum bicolor (L.) Moench] seeds metabolically labeled from [14C]phenylalanine. The [14C]tannin should be useful in determining the metabolic fate of dietary condensed tannin

  17. Dry extraction of 14C02 and 14C0 from Antarctic ice

    Roijen, J.J. van; Bintanja, R.; Borg, R. van den; Broeke, M.R. van den; Jong, A.F.M. de; Oerlemans, J.

    1994-01-01

    A dry extraction method was used to obtain trapped CO, of 2-5 kg ice samples from a blue ice zone in East Antarctica. In situ produced 14C was also extracted in 14C0, and 14C0 concentrations at a ratio of 3.4 f 0.9. Correction of trapped 14C0, from in situ resulted in ice dates in the range 5-15 ka.

  18. Synthesis of steroids 14C-4: acetates of 19-nor-testosterone and testosterone

    The acetates of 19-nor-testosterone 4-14C and testosterone 4-11C have been prepared from ICH3H814C with respective yields of 32 percents and 56 percents in report of ICH3-14C. The cyclization in acid medium has given correct yields in opposition with the cyclization in alkaline medium that gives low yields for the testosterone and negative yields for the 19-nor-testosterone

  19. 14C-carbaryl residues in hazelnut.

    Yücel, Ulkü; Ilim, Murat; Aslan, Nazife

    2006-01-01

    A hazelnut ocak (shrub growing form) in the field in Black Sea region of Turkey was treated with commercial carbaryl insecticide spiked with 14C-carbaryl. Three months later, the harvested hazelnuts were separated into husk, shell, and kernel components, then homogenized and analyzed. The total and unextractable (bound) 14C-residues were determined by combustion and the extractable 14C-residues were obtained by extracting the samples with methanol. Concentrated extracts were first analyzed by thin layer chromatography (TLC). The extracts were also subjected to a series of liquid-liquid extraction procedures for clean-up and the final extracts were analyzed by high performance liquid chromatography (HPLC). Crude hazelnut oil was also extracted with hexane and analyzed for total 14C-residue. A total of 1.3% of applied radioactivity was recovered from the total nut harvested, with 0.04%, 0.06%, and 1.2% present in shell, kernel, and husk, respectively. The results show that the inedible husk and shell contained 95.7% 14C, whereas the edible kernel contained 4.3% of the total 14C recovered. The terminal 14C-residue in hazelnut kernel and oil did not contain carbaryl and/or its metabolite naphthol. PMID:16785168

  20. Chemical digestion and radionuclidic assay of TiNi-encapsulated 32P intravascular brachytherapy sources

    A very quantitative, destructive assay procedure was devised for accurately measuring the 32P activity content of TiNi-encapsulated intravascular brachytherapy sources and was applied to four different sources (termed 'seeds') which were developed and provided by Guidant Intravascular Intervention (formerly NeoCardia). These seeds are intended for use in the prophylactic treatment of restenosis following balloon angioplasty in heart-disease patients. The assays involved the dissolution of the TiNi jacket, extraction of the activity from the internal 32P-containing source material, quantitative solution transfers, and a gravimetrically-based dilution; followed by liquid scintillation (LS) spectrometry of the resulting master solution with 3H-standard efficiency tracing using composition-matched LS cocktails. The LS spectrometry utilized a previously-developed method for resolving the always-present 33P impurity. The protocol included provisions for accounting for all possible losses of 32P in the digestion procedure (based on radiochemical tracing experiments), for any unrecovered activity in the remaining source material, and for any residual activity in the solution-transfer and containing vessels. Sections of the TiNi jackets adjacent to the cut-off active seed portions were also assayed for any contained activity. Such destructive assays were required for relating measurements of the absorbed dose spatial distribution for the seeds to theoretic dose modelling and for establishing calibration factors for subsequent non-destructive radionuclidic measurements on the seeds

  1. (14C)-glucose metabolism during shoot bud development in cultured cotyledon explants of Pinus radiata

    Excised cotyledons of Pinus radiata D. Don cultured under shoot-forming (plus benzyladenine) and non shoot-forming (minus benzyladenine) conditions for 10 and 21 days were fed U-[14C]-glucose for 3 h in the light followed by a 3 h chase period. The labelling of individual metabolites as well as 14C incorporation into protein was assessed. It was found that the general metabolic patterns were qualitatively the same in shoot-forming and non shoot-forming conditions, however, metabolism leading to respiration as well as to the synthesis of some amino acids and protein synthesis was enhanced in the shoot-forming cultures. (author)

  2. Synthesis of [5-14C]-dodecane and [8-14C]-hexadecane

    [5-14C]-Dodecane and [8-14C]-hexadecane were synthesized starting with [1-14C]-octanoic acid. The carboxylic acid was reduced to 1-octanol, which was esterified to n-octyl p-toluenesulfonate. Following a Corey-House procedure, the sulfonate was either reacted with Li[Cu(butyl)2] to [5-14C]-dodecane (40% overall yield), or with Li[Cu(octyl)2] to [8-14C]-hexadecane (24% overall yield). The lithium di-alkyl cuprates were prepared from butyl lithium and n-octyl bromide, respectively. Preliminary experiments with non-labeled compounds using a Wittig reaction as chain extension step, turned out to be less favourable. The Corey-House route provides a simple method for the synthesis of specifically 14C-labeled alkanes from commercially available [1-14C]-carboxylic acids. (author)

  3. Synthesis of ethanol 14C-1

    The direct reduction by LiAlH4, of a suspension of anhydrous sodium acetate in tetra-hydro-furfuryl-oxy-tetra-hydro-pyran is described. This study has shown that the ethanol thus obtained is impure and that the yields are erratic. On the contrary the reduction of acetyl chloride 1-14C by LiAlH4, in 'diethyl carbitol' leads to ethanol 1-14C of satisfactory purity with a yield of about 71 percent. (author)

  4. Multiple DNA adducts in lymphocytes of smokers and nonsmokers determined by 32P-postlabeling analysis

    Identification of DNA adducts in peripheral lymphocytes could serve as a means of monitoring human exposure to potential genotoxic agents. In the study, DNA from peripheral lymphocytes of smokers and nonsmokers was examined for adducts by the P1 nuclease 32P-post-labeling technique. Thin layer chromatography (TLC) maps from both groups revealed multiple DNA adducts which ranged from no adducts for one individual to six adducts for a different individual. The total DNA adduct concentrations were approximately one adduct in 10 to the seventh-10 to the eighth power normal nucleotides. Comparison of the adduct TLC profiles revealed individual variation in both pattern and level of DNA adducts. The type and amount of adduct was not influenced by smoking history and remained unchanged in four out of six subjects who were resampled after a one month interval. One adduct detected in lymphocyte DNA co-migrated on TLC with an adduct derived by in vitro incubation of lymphocytes with benzo(a)pyrene (B(a)P). The 3H-nucloside values were consistent with values obtained by 32P-postlabeling of the same sample (correlation coefficient of 0.88). No relationship was apparent between the capacity of lymphocytes to form a (3H)-B(a)P-derived adduct in vitro and the concentration of the adduct, or total adducts present in untreated lymphocytes

  5. Experimental study on 32P uptake in vivo

    Disturbances in the development of the teeth which were caused by internal irradiation of 32P were studied using rats of Wister strain about one month old. The experiment with a dose of 7 μc/g of 32P showed that 4 of 30 rats died within 90 days of observation. The experiment with a dose of 10 μc/g of 32P showed that none of the rats survived longer than 18 days. Correlationship was found among increase and decrease of the body weight, myelogram of the femoral bone, and ability of the tooth development. The disturbances showed a peak about 20 days after the administration of 32P and then subsided. As regards the relationship between the mechanisms of tooth formation and tooth eruption, reformation of the dentine was noted but no recovery of tooth eruption was noted 30 days after 32P-administration. Some recovery from disturbance of the tooth formation could be observed after 30 days of the administration of 32P. 90 days after the administration, dentin formation could still be noted in the apical part, while germ cells of the tooth had been destroyed completely and peridental tissues had also been destroyed remarkably. Persistent osteoid dentin, characteristic of disturbance of the incisor due to internal irradiation, proliferated in a shape of a belt along the dentin blastocytes in the labial side, gradually infiltrating into the center of the dental pulp. The osteoid dentin proliferated in a shape of lump in the dental germ of the lingual side. In the experiments with 7 μc/g, there was left a possibility of maintaining vital power of rats judging from their weights and myelogram of the femoral bone, while the dose had destructive effects on the incisors. This was substantiated by the fact that the absorbed dose of the incisor was highest among those of the hard tissues. (Ueda, J.)

  6. Use of 32P in aluminum sensibility tests with bean

    Four greenhouse experiments were conducted to study the possibility of using 32P in aluminium tolerance tests of bean (Phaseolus vulgaris L.). The cultivars were previously classified according to dry matter yield date by regression analysis as aluminium tolerant (C20-Mulatinho Paulista; C26-Ricobaio 1014 and C33-Roxo 750) and aluminium sensitive (C17-Jamapa; C28-Rio Tibagi and C34-Tambo). Chopped roots from plant grown in a complete nutrient solution during 30 days and submerged in another solution containing aluminium showed to be a reliable indicator of 32P absorption efficiency to aluminium tolerant and sensitive cultivars. (M.A.C.)

  7. Radioactive waste with 14C in Argentina

    14C is a long half-life radioisotope, which is present in radioactive waste generated during the operation and decommissioning of nuclear power plants. 14C can also be found in waste generated by medical diagnostic laboratories or any one generated by fields that deal with research and development (mainly connected with the biochemists area). According to international precedents the disposal of 14C based on the final amount found in radioactive waste and its chemical form have conditioned the design and operation of the facilities (either because of the amount of it or the chemical form in which 14C was present). We have to take into account that the design of facilities for radioactive waste disposal is included among the obligations of the National Radioactive Waste Management Program (PNGRR). It is absolutely necessary to count with enough information about the characteristics of any waste containing 14C that is generated in Argentina, in order to be able to fulfil the requirements previously mentioned. The main characteristics of interest in the frame of the present project are: a) the principal reactions that take place for the formation of 14C; b) The specific concentration of activity in materials where this radio nuclei is formed or is accumulated; c) To know which is the current step in the process of managing these wastes (in Argentina and all over the world). Either if it refers to bulk or conditioned storage, inside the generating facility; d) Transportation possibilities of 14C under these conditions; e) The accumulated volume and the generation rate of this kind of waste in Argentina. This paper presents an initial collection and evaluation of the information related to the characteristics already mentioned, having gathered published material from the literature and information in the PNGRR up to this moment. The description of the characteristics of the radioactive waste containing 14C from nuclear power plants, hospitals and research and

  8. 14C Behaviour in PWR coolant

    Although 14C is produced in relatively small amounts in PWR coolant, it is important to know its fate, for example whether it is released by gaseous discharge, removed by absorption on ion exchange (IX) resins or deposited on the fuel pin surfaces. 14C can exist in a range of possible chemical forms: inorganic carbon compounds (probably mainly CO2), elemental carbon, and organic compounds such as hydrocarbons. This paper presents results from a preliminary survey of the possible reactions of 14C in PWR coolant. The main conclusions of the study are: - A combination of thermal and radiolytic reactions controls the chemistry of 14C in reactor coolant. A simple chemical kinetic model predicts that CH3OH would be the initial product from radiolytic reactions of 14C following its formation from 17O. CH3OH is predicted to arise as a result of reactions of OH. with CH4 and CH3, and it persists because there is no known radiation chemical reduction mechanism. - Thermodynamic considerations show that CH3OH can be thermally reduced to CH4 in PWR conditions, although formation of CO2 from small organics is the most thermodynamically favourable outcome. Such reactions could be catalysed on active nickel surfaces in the primary circuit. - Limited plant data would suggest that CH4 is the dominant form in PWR and CO2 in BWR. This implies that radiation chemistry may be important in determining the speciation. - Addition of acetate does not affect the amount of 14C formed, but the addition of large amounts of stable carbon would lead to a large range of additional products, some of which would be expected to deposit on fuel pin surfaces as high molecular weight hydrocarbons. However, the subsequent thermal decomposition reactions of these products are not known. - Acetate addition may represent a small input of 12C compared with organic material released from CVCS resins, although the importance of this may depend on whether that is predominantly soluble material or suspended

  9. Current trend of researches on 14C transfer modelling in human and livestock

    Safety of nuclear energy is one of the major tasks in the debate nowadays on future energy resources in the context of climate change and resource vulnerability. There are needed robust dosimetric models for humans as well as reliable predictions of radionuclide dynamics in farm animals and crops and wild species. 14C and 3H need special consideration in the context of waste safety, heavy water reactors and the proposed fusion reactor, as well as fuel reprocessing plants. 14C is unusual, in that it is isotope of macro-elements which form the basis of animal tissues and feed. There are few published values describing the transfer of 14C from feed to animal derived food products under steady state conditions. We recommend that the concentration ratio between feed and animal product activity concentrations can be used as it is less variable than the transfer coefficient. As a result of the close biological and chemical link between OBT and organic carbon, the biological half-times of 14C and 3H in organic forms are likely to be the same and models for 3H and 14C share common parameters. We have recently shown that the currently used single organic compartment models, as used in the ICRP approach, are not appropriate to describe the dynamics of 14C and 3H in mammals as they underestimate long term retention considerably. After an overview of present models in literature, we concentrate on the new developed metabolic model for mammals and test examples (no calibration) are presented for rat, sheep and cow milk. The dosimetric implication of the model will be investigated for further model extension. (author)

  10. Study of the reaction 14 C (p,p) 14 C

    The study of the elastic scattering of polarized protons in 14 C, it has been very limited. Some angular distributions exists to low energy, as well as measures of excitation functions to several angles for the differential section and the vectorial analyzer power. A detailed study of the elastic scattering of protons by 14 C, it give us experimental information of the excited states in 15 N. The study of these states, is since of considerable interest it is not very easy to obtain a target of 14 C also in a reaction 14 C (p,p) 14 C is possible to obtain information of levels in 15 N to an excitation energy EX >14.95 MeV. (Author)

  11. Translocation of 14C-assimilates and 14C-herbicides in cow parsnip (Heracleum sphondylium)

    In cow parsnip translocation fo 14CO2, 14C-2,4-D and 14C-2,4,5-T was investigated during four growth phases. It was intended to find out the quantitative correlation between the translocation of phenoxy herbicides and assimilates. The gas exchange used for 14CO2 application is described. Before shoot extension, the root of the plants is the prefered target for assimilates and 2,4-D. Close quantitative correlation was found between the respective 14C activities as regards direction of translocation and radioactivity per dry weight. Similar results were found with 2,4,5-T. At flowering 14C activity moves clearly into the shoot and the inflorescence. At seed maturity, rhizomes and roots take in the 14C activity preferably. Consequently, two growing phases are recommended for optimal weed control by phenoxy compounds, especially 2,4-D: before shooting or after flowering, if sufficient assimilating leaves are left. (orig.)

  12. Biokinetic and dosimetric investigations of 14C-labeled substances in man using AMS

    Up to now, radiation dose estimates from radiopharmaceuticals, labeled with pure β-emitting radionuclides, e.g., 14C or 3H have been very uncertain. Using accelerator mass spectrometry (AMS) we have derived new and improved data for 14C-triolein and 14C-urea and are currently running a program related to the biokinetics and dosimetry of 14C-glycocholic acid and 14C-xylose. The results of our investigations have made it possible to widen the indications for the clinical use of the 14C-urea test for Helicobacter pylori infection in children. The use of ultra-low activities, which is possible with AMS (down to 1/1000 of that used for liquid scintillation counting), has opened the possibility for metabolic investigations on children as well as on other sensitive patient groups like new-borns, and pregnant or breast-feeding women. Using the full potential of AMS, new 14C-labeled drugs could be tested on humans at a much earlier stage than today, avoiding uncertain extrapolations from animal models

  13. Applications of 10Be, 14C, and 32Si to geological questions

    Radiometric dating is regarded as fundamental to any modern timescale calibration. In terms of available isotopic dating and tracing tools in environmental sciences, the cosmogenic isotopes stand out because of their application in the range from the very recent up to the middle Miocene. At IGNS, three long-lived cosmogenic isotopes can be measured. 14C (half life=5730 years) and 10Be (half-life = 1.5 Ma) are measured by Accelerator Mass Spectrometry (AMS) of 10Be/9Be and 14C/13C ratios, while 32Si (half-life > 140 years) is measured by radioactive decay counting of its daughter-product 32P. The main advantage of AMS over decay counting is the relatively small amount of sample material needed. AMS has made it feasible to measure ultra-low concentrations of long-lived isotopes such as 10Be. (author)

  14. Leaf absorption of 32P in the pumpkin

    The author presents a method to study the influence of various factors of the absorption of 32P applied under the form of phosphates by a plant cultivated in conditions ensuring a normal development. Experiments provided indications on leaf absorption and 32P transport by pumpkin leaves: phosphor 32 is absorbed and then quickly transported into the different organs of the plant (24 hours after treatment, it is present in aerial and underground parts), the quantity of absorbed phosphor increases with phosphor concentration in the applied solution, atmosphere humidity is an important factor for phosphor penetration into the leaves, plants absorb phosphor in darkness as well as in light, and the absorption of phosphor is not modified when applied with low glucose concentrations

  15. 14C measurements in aquifers with methane

    A survey of various groundwater systems indicates that methane is a common trace constituent and occasionally a major carbon species in groundwaters. Thermocatalytic methane had delta13CCH4 > -45%0 and microbially-produced or biogenic methane had delta13CCH4 0. Groundwaters containing significant biogenic methane had abnormally heavy delta13C values for the inorganic carbon. Thermocatalytic methane had no apparent effect on the inorganic carbon. Because methanogenesis seriously affects the carbon isotope geochemistry of groundwaters, the correction of raw 14C ages of affected groundwaters must consider these effects. Conceptual models are developed which adjust the 14C activity of the groundwater for the effects of methanogenesis and for the dilution of carbon present during infiltration by simple dissolution of rock carbonate. These preliminary models are applied to groundwaters from the Alliston sand aquifer where methanogenesis has affected most samples. In this system, methanogenic bacteria using organic matter present in the aquifer matrix as substrate, have added inorganic carbon to the groundwater which has initiated further carbonate rock dissolution. These processes have diluted the inorganic carbon 14C activity. (orig.)

  16. Photoproton cross section for 14C

    Using bremsstrahlung, the 14C(γ,p) reaction cross section has been measured from threshold to 29 MeV. The integrated cross section up to 30 MeV is 18±3 MeV mb. Above 23.5 MeV, the reported cross section includes a contribution, estimated at 3.5 MeV mb, due to the 14C(γ,d) and 14Cγ,pn) reactions. Essentially the entire 14C(γ,p) cross section results from decay of T> dipole states. From knowledge of other decay channels estimates of the cross section, integrated to 30 MeV for the T and T> components of the giant resonance (GDR) of 81 MeV mb and 43 MeV mb are obtained. The splitting of the mean energies of the GDR isospin components is 8.5 MeV. Comparisons with several shell-model calculations are made with the data, and general agreement is found. A comparison of photonuclear absorption cross sections for 12,1314C and 16,17,18 O shows dramatic redistribution of dipole strength as neutrons are added to the core nuclei. 41 refs., 1 tab., 7 figs

  17. 14C analysis via intracavity optogalvanic spectroscopy

    A new ultra sensitive laser-based analytical technique, intracavity optogalvanic spectroscopy (ICOGS), allowing extremely high sensitivity for detection of 14C-labeled carbon dioxide has recently been demonstrated. Capable of replacing accelerator mass spectrometers (AMS) for many applications, the technique quantifies zeptomoles of 14C in sub micromole CO2 samples. Based on the specificity of narrow laser resonances coupled with the sensitivity provided by standing waves in an optical cavity, and detection via impedance variations, limits of detection near 10-1514C/12C ratios have been obtained with theoretical limits much lower. Using a 15 W 14CO2 laser, a linear calibration with samples from 5 x 10-15 to >1.5 x 10-12 in 14C/12C ratios, as determined by AMS, was demonstrated. Calibration becomes non-linear over larger concentration ranges due to interactions between CO2 and buffer gas, laser saturation effects and changes in equilibration time constants. The instrument is small (table top), low maintenance and can be coupled to GC or LC input. The method can also be applied to detection of other trace entities. Possible applications include microdosing studies in drug development, individualized sub-therapeutic tests of drug metabolism, carbon dating and real time monitoring of atmospheric radiocarbon.

  18. Decomposition and excretion of 32P-naled in milk

    The 32P-labelled organophosphorus insecticide naled is decomposed in milk in vitro at 5 0C with a half-life of 35 h with dichlorvos as a metabolite, that is also formed at short time heating and UV-irradiation. The recovery in milk powder is 25% (naled + dichlorvos) of the initial concentration. Following spray application of 0.05 mg naled/kg body mass to 2 lactating cows, 5 - 8 ppb of naled and 7 - 9 ppb of dichlorvos were found in the milk 5 h after application, not exceeding the tolerance level of 0.02 mg/kg according to regulations in the GDR. (author)

  19. Forensic applications of 14C at CIRCE

    The decreasing trend of the radiocarbon pulse produced during the atmospheric tests of nuclear weapons (bomb-carbon) coupled with high sensitivity accelerator mass spectrometry (AMS) measurements, drastically increased the precision of radiocarbon age determinations since the second part of the sixties, allowing the application of radiocarbon AMS to a wide range of studies previously not directly involving conventional radiocarbon dating (i.e. food authenticity, forensic, biochemistry). In the framework of authenticity evaluation of artworks, high precision radiocarbon (14C) AMS measurements (ΔR/R 14C dating achieved high precision measurements opening the opportunity to these kinds of applications. This paper presents the main results obtained from radiocarbon measurements on a set of bone samples analyzed for the determination of the post-mortem interval in the framework of an unsolved case investigated by the Rome prosecutor office. The chronological characterization of the wooden support of the “Acerenza portrait” is also presented with the aim to evaluate its age and to further investigate the possibility to attribute this artwork to Leonardo da Vinci. Bomb-14C dating on the lipid and collagen fractions of bones allows the evaluation of the year of the death of the individuals by means of ad hoc calibration data sheet with the typical few years precision and difference between collagen apparent age and the year of death appeared in agreement with the age of one individual estimated by dating of tooth collagen. Conventional radiocarbon dating on both wood and wood extracted cellulose leads to an estimation of the portrait wood board age (2σ) of 1459–1524 AD (57% relative probability), 1571–1631 AD interval (42% relative probability).and 1559–1563 AD (1% relative probability). These results attribute with the highest relative probability an age comprised within the life span of Leonardo (1452–1519) to the support.

  20. Synthesis of dexamethasone-4-14C

    The bismethylenedioxy (BMD) derivative of dexamethasone 2 was silylated with trimethylchlorosilane and imidazole in dimethylformamide to give the 11β-trimethylsilyloxy BMD derivative 3. The Δ1-double bond in 3 was hydrogenated over 5% palladium on carbon to give the Δ4-3-oxo steroid 4. Oxidation of 4 with potassium permanganate-sodium metaperiodate gave the seco-acid 5 which on subsequent treatment with acetic anhydride; sodium acetate and triethylamine gave the enol-lactone 6. The enol-lactone 6 was reacted with 14C-methylmagnesium iodide to give an adduct 7a which on heating at reflux with lithium 2,6-di-t-butylphenoxide in dioxane gave the Δ4-3-oxo derivative 8. Compound 8 was heated at reflux with m-iodylbenzoic acid and diphenyl diselenide in toluene to give the Δsup(1,4)-3-oxo steroid 9. The protecting BMD and silyl groups were removed in a single step by reaction with aqueous trifluoroacetic acid containing 2N hydrochloric acid at room temperature to give dexamethasone-4-14C 10. (author)

  1. Forensic applications of 14C at CIRCE

    Marzaioli, F.; Fiumano, V.; Capano, M.; Passariello, I.; Cesare, N. De.; Terrasi, F.

    2011-12-01

    The decreasing trend of the radiocarbon pulse produced during the atmospheric tests of nuclear weapons (bomb-carbon) coupled with high sensitivity accelerator mass spectrometry (AMS) measurements, drastically increased the precision of radiocarbon age determinations since the second part of the sixties, allowing the application of radiocarbon AMS to a wide range of studies previously not directly involving conventional radiocarbon dating (i.e. food authenticity, forensic, biochemistry). In the framework of authenticity evaluation of artworks, high precision radiocarbon ( 14C) AMS measurements (Δ R/ R Leonardo da Vinci. Bomb- 14C dating on the lipid and collagen fractions of bones allows the evaluation of the year of the death of the individuals by means of ad hoc calibration data sheet with the typical few years precision and difference between collagen apparent age and the year of death appeared in agreement with the age of one individual estimated by dating of tooth collagen. Conventional radiocarbon dating on both wood and wood extracted cellulose leads to an estimation of the portrait wood board age (2σ) of 1459-1524 AD (57% relative probability), 1571-1631 AD interval (42% relative probability).and 1559-1563 AD (1% relative probability). These results attribute with the highest relative probability an age comprised within the life span of Leonardo (1452-1519) to the support.

  2. Pharmacokinetics and tissue distribution of 14C-5-aminosalicylic acid (14C-5-ASA) in rats

    5-Aminosalicylic acid (5-ASA) is effective in the treatment of ulcerative colitis and Crohn's disease. As part of a preclinical metabolism profile with 5-ASA, we evaluated the tissue level and distribution of 14C-5-ASA in rats. Biodistribution of 14C-radioactivity was determined in the major organs of rats after a single oral dose (34 mg/kg; 15 uci/rat). Data from tissue area under the curve (AUC 0-72) indicated that the highest amounts of radioactivity were retained in cecum (481.1 hr.ug.equ/gm), colon-rectum (178.5 hr.ug.equ/gm), ileum (166.7 hr.ug.equ/gm), jejunum (65.5 hr.ug.equ/gm), followed by kidneys (58.0 hr.ug.equ/gm) and liver (14.8 hr.ug.equ/gm). The radioactivity retained in tissues at 72 hours postdose was wither nondetectable or less than 0.1 ppm. The radioactivity concentration in blood was highest at 0.5 hr (tmax) postdose and the terminal half-life (t1/2) of 14C-radioactivity (5-ASA + metabolite) was 2.7 hours. 14C-5-ASA is absorbed and distributed in the body. The greatest amount of 14C-radioactivity was found in the stomach and GI tract. 14C-5-ASA was eliminated completely (44.9% in the urine, 51.7% in the feces) 72 hours after administration without significant tissue retention

  3. Forensic applications of 14C at CIRCE

    Marzaioli, F.; Fiumano, V.; Capano, M.; Passariello, I.; Cesare, N. De.; Terrasi, F.

    2011-12-01

    The decreasing trend of the radiocarbon pulse produced during the atmospheric tests of nuclear weapons (bomb-carbon) coupled with high sensitivity accelerator mass spectrometry (AMS) measurements, drastically increased the precision of radiocarbon age determinations since the second part of the sixties, allowing the application of radiocarbon AMS to a wide range of studies previously not directly involving conventional radiocarbon dating (i.e. food authenticity, forensic, biochemistry). In the framework of authenticity evaluation of artworks, high precision radiocarbon ( 14C) AMS measurements (Δ R/ R < 0.3%) reduce the conventional uncertainty of the dating to few decades, allowing precise age estimation of materials containing carbon (C). The Centre for Isotopic Research on Cultural and Environmental heritage (CIRCE) during its activity on AMS 14C dating achieved high precision measurements opening the opportunity to these kinds of applications. This paper presents the main results obtained from radiocarbon measurements on a set of bone samples analyzed for the determination of the post-mortem interval in the framework of an unsolved case investigated by the Rome prosecutor office. The chronological characterization of the wooden support of the "Acerenza portrait" is also presented with the aim to evaluate its age and to further investigate the possibility to attribute this artwork to Leonardo da Vinci. Bomb- 14C dating on the lipid and collagen fractions of bones allows the evaluation of the year of the death of the individuals by means of ad hoc calibration data sheet with the typical few years precision and difference between collagen apparent age and the year of death appeared in agreement with the age of one individual estimated by dating of tooth collagen. Conventional radiocarbon dating on both wood and wood extracted cellulose leads to an estimation of the portrait wood board age (2σ) of 1459-1524 AD (57% relative probability), 1571-1631 AD interval (42

  4. Production of 14C-labeled gas in BACTEC Neisseria Differentiation kits by Neisseria cinerea.

    Boyce, J M; Mitchell, E B; Knapp, J S; Buttke, T M

    1985-01-01

    Six strains of Neisseria cinerea were tested in BACTEC Neisseria Differentiation kits (Johnston Laboratories, Inc., Towson, Md.), and all yielded positive glucose growth indices and negative maltose and fructose growth indices. These results were similar to those achieved with Neisseria gonorrhoeae. However, most of the N. cinerea isolates tested yielded 3-h glucose growth indices that were lower than those obtained with gonococci. 14C-labeled gas was produced significantly faster (P less tha...

  5. Biosynthesis of riboflavin. Enzymatic formation of the xylene moiety from [14C]ribulose 5-phosphate.

    Nielsen, P; Neuberger, G; Floss, H G; Bacher, A

    1984-02-14

    We have studied the enzymatic formation of the xylene ring of riboflavin using cell extracts from the flavinogenic yeast Candida guilliermondii. 5-Amino-6-ribitylamino-2,4(1H,3H)-pyrimidinedione or its 5'-phosphate could serve as substrates. In addition, a pentose phosphate or pentulose phosphate was required. Experiments with [14C]ribulose 5-phosphate gave evidence for the incorporation of the ribulose carbon atoms except C-4 into the xylene ring of the vitamin. PMID:6546684

  6. Quantifying 32P-labeled and unlabeled nucleic acids

    Recombinant DNA technology depends on detection methods for nucleic acids compatible with amounts ranging from picograms to grams and from tenths of a microliter to liters. In practical terms there are three basic techniques: (1) absorbance methods suitable for a minimum concentration of micrograms per milliliter, (2) fluorescence methods capable of detecting nanograms of DNA and micrograms of RNA, and (3) methods based on the detection of 32P. Because of the overwhelming importance in molecular biology of the third group, this chapter will stress exquisitely sensitive methods for measuring radioactivity in very small volumes. An illustration in which an enzyme-catalyzed reaction performed in 20 μl is monitored by consuming less than 2% of the total volume will be presented

  7. Essential thrombocythemia treated with oral sup(32)P

    A 65-year old man was admitted due to protracted gum bleeding after dental surgery. The peripheral blood smear showed thrombocytosis(1,160,000/mm3) with bizarre, giant platelets. The paltelet adhesiveness revealed 28% (normal control 31-85%) by Salzman method and the platelet aggregation revealed moderately delayed response to collagen, but normal responsiveness to A.D,P, and no responsiveness to epinephrine, the spleen scan(sup(99m)Tc-NaTcO4) showed the finding of splenic infraction. The gum bleeding ceased after transfusion of 8 units of platelet rich plasma, and he was treated with oral sup(32)P(2.5mCi/m2) under the diagnosis of essential thrombocythemia. The platelet count returned toward normal 2 months after treatment, and he was in good healthy condition. (Author)

  8. [Disintegration and elimination of 32P-naled in milk].

    Dedek, W; Scheybal, A; Gabrio, T; Kirst, E

    1981-01-01

    The organophosphorus insecticide naled (O,O-dimethyl-O,O-(1,2-dibromo-2,2-dichloroethyl)-phosphate, labeled by 32P] is degraded in milk in vitro at 5 degrees C with a half-life of 35 h with dichlorvos as a metabolite, that is also formed at short time heating and UV-irradiation. The recovery in milk powder is 25% (naled + dichlorvos) of the initial concentration. Following spray application of 0,05 mg naled/kg body mass to 2 lactating cows, 5-8 ppb of naled and 7-9 ppb of dichlorvos were found in the milk 5 h p.a., not exceeding the given tolerance level of 0,02 mg/kg in the German Democratic Republic. PMID:7290169

  9. Phosphate fertilizer studies using 32P dilution technique

    Agronomic effectiveness of highly soluble phosphate fertilizers for annual crop production is well known and documented. In recent years considerable research effort has been focused on search for alternative means of cheaper forms of P fertilizers to fill the needs of poor farmers, who has limited capital availability for purchase of fertilizers. Since some countries in the world have naturally occurring phosphate rocks (PR), the most appealing alternative is for direct application of PR. The low capital and energy inputs required to prepare these PR for use makes it the cheapest mineral P fertilizers possible. Thailand, Sri Lanka, Indonesia and Vietnam are some countries in the Asian region blessed with natural PR. Coupled with the inherently acidic and P deficient soils found in this region, research on direct application of these PR for crop production is indeed timely. Studies done in the temperate regions on direct application of PR have concluded that PR are not suitable for use in intensive agricultural system, because PR cannot maintain a sufficiently high P concentration in the soil solution for high crop yields. Research in direct application of PR to acidic soils of the Asian region have proven otherwise. The use of radioactive 32P isotope has helped in quantification of the amounts of P from the PR tested being utilized by the crop, and its distribution in the plant can also be monitored. In Malaysia, highly reactive North Carolina phosphate rock has been found to be as effective as triple superphosphate, where a total of about 18% of the P fertilizer applied was utilized by three consecutive crops of sweet corn grown under field conditions. Initial glasshouse screening of efficacy of PR can also be determined by the use of the 32P isotope. (author). 16 refs, 6 figs, 6 tabs

  10. Synthesis of [methyl-14C]crotonobetaine from DL-[methyl-14C]carnitine

    The causes of carnitine deficiency syndromes are not completely understood, but decomposition of L-carnitine in vivo is likely to be involved. Carnitine is metabolized to γ-butyrobetaine, and crotonobetaine is probably an intermediate in this pathway. To validate experimentally the precursor-product relationship between the three physiologically occuring γ-betaines - L-carnitine, crotonobetaine, γ-butyrobetaine - labelling with stable or radioactive isotopes became necessary. Methyl-labelled carnitine isomers (L(-)-, D(+)- or DL-) or γ-butyrobetaine can be easily synthesized by methylation of 4-amino-3-hydroxybutyric acid isomers or 4-aminobutyric acid, respectively. Because of problems with the 4-aminocrotonic acid, we synthesized labelled crotonbetaine from labelled carnitine. Thus, DL-[methyl-14C]carnitine was dehydrated by reaction with concentrated sulfuric acid. After removal of the latter the products were separated and purified by ion exchange chromatography on DOWEX 50 WX8 (200 - 400 mesh) and gradient elution with hydrochloric acid. In addition to the labelled main product [methyl-14C]crotonobetaine (yield about 50 %), [methyl-14C]glycine betaine and [methyl-14C]acetonyl-trimethylammonium (ATMA) were formed. The end products were identified by combined thin layer chromatography/autoradiography and quantified by liquid scintillation counting. (Author)

  11. A novel synthesis of ethanolamine-2-14C

    Ethanolamine-2-14C was prepared by the reduction of benzyloxycarbonyl-glycine-1-14C methyl ester. The reduction was carried out with calcium borohydride and the protecting group was removed by hydrogenolysis. (author)

  12. Rarotonga Radiocarbon (delta 14C) for 1950 to 1997

    National Oceanic and Atmospheric Administration, Department of Commerce — Rarotonga coral radiocarbon (14C) timeseries. Coral radiocarbon (Delta-14C) on untreated, low-speed drilled samples. Precision is +/- 4 per mil as documented by an...

  13. 14C-glucose binding assay of the glucose transporter binding sites in muscular cell membrane

    A method of determining the binding sites of glucose transporter in rat muscular cell membrane was introduced. The crude products of cell membrane form the skeletal muscle of control and insulin treated rats were prepared, and then fractionated in sucrose gradient. Both plasma membrane and microsome membrane were incubated with D-[U-14C] glucose respectively for the measurement of radioactivity and Scatchard plot analysis. It was found that the binding sites of glucose transporter in plasma membrane and intracellular membrane were 5.6 nmol 14C-glucose/mg protein and 8.7 nmol 14C-glucose-mg protein respectively at basic state. Insulin treatment in experimental groups caused approximately 146% increase in plasma membrane fraction and 88% decrease in intracellular membrane fraction. Moreover, the kinetic data of Scatchard plot curve were similar to those of the [3H]-cytochalasin B binding assay. D-[U-14C] glucose binding assay of glucose transporter binding sites in muscular cell membrane is simple, easy and practicable. The D-[U-14C] glucose is commercially available

  14. Endosulfan - 14C: degradation in soil

    The degradation of (14C) endosulfan was studied after incubation in sterilized and non-sterilized samples of three oxisols, most frequently cultivated with cotton, in Brazil. In sterilized soils the extracted residues were about 80% the bound residues varied from 6 to 14% and the total residues, from 90 to 102%, presenting small variation during a period of 160 days of incubation. The non-sterilized soils, after 160 days of incubation, showed 38, 45 and 43% of extracted residue; 34, 23 and 30% of bound residue; and 72, 68 and 73% of total residue. The evolution of CO2 was very low in the three soil types, being 0.3% and 0.4% in sterilized and non-sterilized soils, respectively, during a period of 48 days of incubation. These low values showed that no great mineralization of endosulfan occurred in this period. TLC analyses of extracted residue showed differences for sterilized and non-sterilized soils. In sterilized soil appeared alpha endosulfan, beta endosulfan, endosulfan sulfate, while in non-sterilized soils appeared alpha and beta endosulfan, endosulfan sulfate and endosulfan diol. (author)

  15. Synthesis of 1-[14C]methyl-1H-tetrazole-5-thiol([14C]NMTT) and [NMTT-[14C

    The title compounds were prepared for metabolic studies, with the 14C labelling being made at methyl of the 1-methyl-1H-tetrazol-5-ylthio (NMTT) group in overall radiochemical yields of 26% and 22% based on barium [14C]carbonate, respectively. (author)

  16. Autoradiographic disposition of [1-methyl-14C]- and [2-14C]caffeine in mice

    Male, C57B1/6J mice received either [1-methyl-14C]caffeine or [2-14C]caffeine via the tail vein at a dose of 0.7 or 11 mg/kg, respectively. At 0.1, 0.33, 1, 3, 9, and 24 hr after treatment, the mice were anesthetized with ether and frozen by immersion in dry ice/hexane. The mice were processed for whole-body autoradiography by the Ullberg technique; this procedure does not allow thawing or contact with solvents. All autoradiographs revealed some retention of radioactivity at early time intervals in the lacrimal glands, seminal vesicle fluid, nasal and olfactory epithelium, and retinal melanocytes. The remaining portion of the animal was densitometrically uniform except for the lower levels noted in the CNS and adipose tissues. Excretion of radioactivity by the liver and kidneys seems to be the major routes of elimination. Localization in the liver at late time intervals was confined principally to the centrilobular region. Late sites of retention, observed only after [1-methyl-14C]caffeine administration, included the pancreas, minor and major salivary glands, splenic red pulp, thymal cortex, bone marrow, and gastrointestinal epithelium. Sites of localization present in both studies included the olfactory epithelium, lacrimal glands, hair follicles, and retinal melanocytes. Further studies are needed to determine whether the localization at these various sites is due to metabolic degradation, active transport, or possibly a specific receptor interaction

  17. Fractionation of applied 32P labeled TSP in calcareous soils

    Calcareous dark brown red soil (calcixerollic xerochrept) from northern Syria was used in a pot experiment to study the fate of triple super phosphate fertilizer (TSP) with and without a crop (Local durum wheat (Triticum turgidum L. group durum (Desf)) c v. Bohouth). The soil received 17μg P/g soil of 32 P labeled TSP, and samples were collected from soils and plants at successive dates. Soil inorganic P was ≅94% of total soil P, with only 50-80% being soluble. Calcium phosphate compounds were the dominant fraction (≤68%) of the soluble inorganic soil P followed by occluded iron phosphate (≤48%) and all other fractions were ≤9%. Isotopic measurements showed that ≅ 50% of fertilizer P was nonexchangeable within 2 days, and TSP values in each fraction of soil inorganic P fluctuated in relatively similar proportions to the concentrations of fractions in soil. Available P (soil and TSP) in cropped soil was more than that in the uncropped soil, and plants had no effect on the distribution of P from fertilizer amongst the different P fractions. (author)

  18. An overview of DNA fingerprinting with sup 32 P nucleotides

    Pappas, G.G.

    1992-01-01

    The DNA probes radiolabeled with {sup 32}P, a primary tool employed by researchers in the life sciences for > 20 yr, are used by private companies, state-run laboratories, and the FBI to generate autoradiographs displaying the unique banding patterns that constitute the DNA fingerprint. The ability to identify an individual or animal from a biological sample has profound implications. Unidentified bodies, unrecognizable remains, and missing children can be tested and the DNA fingerprint compared to those of family members for positive identification. Paternity can be established before a child's birth. Immigration disputes can easily be resolved. Other uses include pedigree determination and testing for cell-line cross-contamination. Using a DNA fingerprint to determine the guilt or innocence of an individual allegedly involved in a violent crime is very controversial and has great legal and moral implications for society. Forensic laboratories have been challenged to ensure a level of quality control and quality assurance consistent with the weight given to these tests when used as evidence in a court of law.

  19. An overview of DNA fingerprinting with 32P nucleotides

    The DNA probes radiolabeled with 32P, a primary tool employed by researchers in the life sciences for > 20 yr, are used by private companies, state-run laboratories, and the FBI to generate autoradiographs displaying the unique banding patterns that constitute the DNA fingerprint. The ability to identify an individual or animal from a biological sample has profound implications. Unidentified bodies, unrecognizable remains, and missing children can be tested and the DNA fingerprint compared to those of family members for positive identification. Paternity can be established before a child's birth. Immigration disputes can easily be resolved. Other uses include pedigree determination and testing for cell-line cross-contamination. Using a DNA fingerprint to determine the guilt or innocence of an individual allegedly involved in a violent crime is very controversial and has great legal and moral implications for society. Forensic laboratories have been challenged to ensure a level of quality control and quality assurance consistent with the weight given to these tests when used as evidence in a court of law

  20. Muon capture on 3H

    Golak, J; Witala, H; Topolnicki, K; Kamada, H; Nogga, A; Marcucci, L E

    2016-01-01

    The muon capture on 3H leading to muonic neutrino and three neutrons in the final state is studied under full inclusion of final state interactions. Predictions for the three-body break-up of 3H are calculated with the AV18 potential, augmented by the Urbana IX three-nucleon force. Our results are based on the single nucleon weak current operator comprising the dominant relativistic corrections. This work is a natural extension of our investigations of the muon capture on 3He leading to 3H or n+d or n+n+p and muonic neutrino in the final state, presented in Phys. Rev. C90, 024001 (2014).

  1. 14C AMS dating Yongcheon cave

    The biggest island in South Korea is Jeju Island, which lies 80 km south of the mainland and has one shield volcano, Mt. Halla. The volcanic island and its lava tubes were added to the world heritage list by UNESCO in 2007. Among the many lava tubes on the island, a unique cave had been accidentally found in 2005 while some workers were replacing a telephone pole. Until the discovery, it had been completely isolated from the outside by naturally-built sand blocks. Yongcheon cave is a lime-decorated lava tube showing both the properties of a volcanic lava tube and a limestone cave. This cave, about 3 km in length, is acknowledged to be the best of this type in the world and includes a large clean-water lake, lava falls, and richly developed speleothems inside it. Even though there is archaeological evidence from well preserved pottery that ancient people entered this place, the preservation of artifacts was ensured by a geological change that made later entrance difficult. We have collected charcoal samples scattered around the cave and dated them using AMS. Ages were in the range of ca. 1570-1260 BP (A.D. 340–880) and this corresponds to the Ancient Three Kingdoms and the Unified Silla era in Korean history. The 14C AMS measurement results presented in this paper on wood charcoal provide precise dates which will be very useful not only to clarify the nature of human activities in this cave but also to provide reference dates when comparing other dating methods.

  2. {sup 14}C AMS dating Yongcheon cave

    Lee, J.H., E-mail: jefflee@snu.ac.kr [AMS Lab., NCIRF, Seoul National University, Seoul 151-742 (Korea, Republic of); Choe, K. [AMS Lab., NCIRF, Seoul National University, Seoul 151-742 (Korea, Republic of); Kim, J.C. [Dept. of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of); Choi, S.H.; Kang, J.; Song, S.; Song, Y.M. [AMS Lab., NCIRF, Seoul National University, Seoul 151-742 (Korea, Republic of); Jang, J.G. [Jeju National Museum, Jeju 690-782 (Korea, Republic of)

    2013-01-15

    The biggest island in South Korea is Jeju Island, which lies 80 km south of the mainland and has one shield volcano, Mt. Halla. The volcanic island and its lava tubes were added to the world heritage list by UNESCO in 2007. Among the many lava tubes on the island, a unique cave had been accidentally found in 2005 while some workers were replacing a telephone pole. Until the discovery, it had been completely isolated from the outside by naturally-built sand blocks. Yongcheon cave is a lime-decorated lava tube showing both the properties of a volcanic lava tube and a limestone cave. This cave, about 3 km in length, is acknowledged to be the best of this type in the world and includes a large clean-water lake, lava falls, and richly developed speleothems inside it. Even though there is archaeological evidence from well preserved pottery that ancient people entered this place, the preservation of artifacts was ensured by a geological change that made later entrance difficult. We have collected charcoal samples scattered around the cave and dated them using AMS. Ages were in the range of ca. 1570-1260 BP (A.D. 340-880) and this corresponds to the Ancient Three Kingdoms and the Unified Silla era in Korean history. The {sup 14}C AMS measurement results presented in this paper on wood charcoal provide precise dates which will be very useful not only to clarify the nature of human activities in this cave but also to provide reference dates when comparing other dating methods.

  3. Modelling the transfer of 3H and 14C into the environment - lessons learn from IAEA's EMRAS project

    Future development of nuclear energy in the frame of climate change and sustainable development needs an increased safety and consequently, robust models of environmental transfer of radio-nuclides. Tritium and Carbon are life elements and must be treated separately from trace elements. The IAEA promoted EMRAS (Environmental Modelling for Radiation Safety) project in order to decrease uncertainties in the predictive capability of environmental models, including the cases of aquatic and biota. To understand the processes and models reliability, nine scenarios have been developed. The Working Group contributed to the Revision of 'Handbook of parameter values for the prediction of radionuclide transfer in temperate environments' TRS 364, as well. The main task of this paper is to propose ways for models' predictive power improvements, based on lessons learnt from EMRAS' exercises. (author)(tk)

  4. Uptake of 3H-choline and synthesis of 3H-acetylcholine by human penile corpus cavernosum

    The neuroeffectors which relax penile smooth muscle and lead to erection are unknown; physiological studies of human corpus cavernosum, in vitro, have suggested a significant role of cholinergic neurotransmission. To further characterize the importance of cholinergic nerves, biopsies of human corpus cavernosum were obtained at the time of penile prosthesis implantation. Tissues were incubated in 3H-choline (10-5M, 80 Ci/mmol) in oxygenated physiological salt solution at 370C, pH 7.4 for 1 hour. Radiolabelled compounds were extracted with perchloric acid (0.4 M) and acetylcholine and choline were separated by HPLC; 14C-acetylcholine was used as internal standard. 3H-choline was accumulated by the tissues (20 +/- 1.9 fmol/mg), and 3H-acetylcholine was synthesized (4.0 +/- 1.1 fmol/mg). In control experiments, heating of the tissue blocked synthesis of 3H-acetylcholine. Inhibition of high affinity choline transport by hemicholinium-3 (10-5M) diminished tissue accumulation of 3H-choline and significantly reduced the synthesis of 3H-acetylcholine (0.5 +/ 0.2 fmol/mg, p < 0.05). These results provide direct evidence of neuronal accumulation of choline and enzymatic conversion to acetylcholine in human corpus cavernosum. Taken together with the physiological studies, it can be concluded that cholinergic neurotransmission in human corpus cavernosum plays a role in penile erection

  5. Increased [32P]-phosphorylation of tryptic peptides of erythrocyte spectrin in Duchenne muscular dystrophy

    Increased [32P]-incorporation in tryptic peptides of the erythrocyte membrane protein spectrin Band 2 in Duchenne muscular dystrophy (DMD) was studied in a consecutive series of 10 matched DMD/control pairs. Spectrin was [32P]-phosphorylated by cyclic AMP-independent endogenous membrane protein kinase in the presence of [gamma-32P]ATP. [32P]-labeled spectrin was isolated, purified, and subjected to tryptic cleavage with excess trypsin. The resulting peptides were separated on a high-resolution 5%/15% stacking SDS--polyacrylamide gel electrophoresis system. Liquid scintillation counting was performed on sequential slices of unstained gels. A broad [32P]-labeled band containing a number of [32P]-polypeptides was found to be more highly [32P]-phosphorylated in DMD patients than in their matched controls. This band migrated with an apparent molecular mass of 4.8-5.2 kilodaltons and contained approximately 55% of total [32P] radioactivity covalently bound to spectrin peptides. These data demonstrated an increased [32P]-phosphorylation of an identifiable tryptic peptide fraction in DMD that is consistent with previous reports of increased spectrin Band 2 [32P]-phosphorylation in DMD

  6. Fate of 14C-labelled compounds in marine environment

    Model ecosystems have played an important role in predicting environmental behavior of agrochemicals. The microcosms used in these studies generally include soil units containing usual biotic components common for that ecosystem. In present studies, scope of two such ecosystems has been extended to study the fate of 14C-labelled pesticides in marine environment. 14C-labelled pesticides used in these studies were chlorpyrifos, DDT and HCH. Two systems were developed in laboratory simulating marine environment to study the fate of these pesticides. The first system was developed in an all glass aquarium tank with marine sediments, seawater, clams and algae and is referred to as marine ecosystem. The second system was developed to permit the total 14C-mass balance studies. It contained marine sediments under moist (60% water holding capacity) or flooded conditions and it is referred to as continuous flow system. Fate of 14C-DDT was studied in marine ecosystem while degradation of 14C-chlorpyrifos and 14C-HCH was studied in continuous flow system. 14C-DDT did not bioaccumulate in clams while at the end of 60 days 50% of the applied 14C-activity was present in sediment fraction of marine ecosystem. 14C-HCH degradation showed about 22-26% mineralization while 45-55% of the applied activity was recovered as organic volatiles. No significant bound residues were formed. 14C-chorpyrifos underwent considerable degradation in marine environment. TCP was the major degradation product. (author)

  7. Method of preparing orotic acid labelled with radioisotope 14C

    The method is presented of universally labelled (U-14C)-orotic acid of a mole activity higher than 250 mCi/mMole. The Claisen condensation with (1,2-14C)-oxalic acid ethylester and (1,2-14C)-acetic acid ethylester having mole activities higher than 50 mCi/milliatom 14C results in the sodium salt of (U-14C)-oxalacetic acid ethylester. When reacted with S-methyl-(14C)-isothiouronium iodide (having an activity higher than 50 mCi/mMole), the substance yields S-methyl-(U-14C)-2-thioorotic acid ethylester whose hydrolysis in an acid medium results in (U-14C)-orotic acid. The (U-14C)-orotic acid can easily be separated from the reaction mixture in the form of precipitate which chemically and radiochemically is almost pure. When an inactive oxalic acid ethylester is used for synthesis, (2,4,5-14C)-orotic acid of a mole activity higher than 150 mCi/mMole can be prepared using the procedure described. (B.S.)

  8. 32P-postlabelling analysis of DNA adducted with urinary mutagens from smokers of black tobacco.

    Peluso, M; Castegnaro, M; Malaveille, C; Talaska, G; Vineis, P; Kadlubar, F; Bartsch, H

    1990-08-01

    In order to characterize the tobacco-derived mutagens excreted in the urine of tobacco smokers, 32P-postlabelling techniques were used to examine DNA adducts formed from these mutagens with calf thymus DNA in the presence of a metabolic activation system (rat liver S9, Aroclor 1254-induced, with or without acetyl coenzyme A). Using either nuclease P1 or butanol extraction procedures, four-six and three spots, respectively, were reproducibly found on the autoradiograms in the case of the urine extract from two smokers of black tobacco. Using the urinary extract from a non-smoker, only three faint spots were detected after nuclease P1 enrichment. DNA adducts produced in smokers' urine were then compared with those formed by four N-hydroxyarylamines, N-hydroxy-2-amino-3,8-dimethyl-3H-imidazo[4,5-f]quinoxaline, N-hydroxy-2-amino-3-methyl-imidazo[4,5-f]quinoxaline, N-hydroxy-2-naphthylamine and N-hydroxy-4-aminobiphenyl. Visual inspection revealed that none of the reference aromatic amines contributed to the adduct pattern produced by the urinary mutagen(s). However, primary aromatic amines are mainly implicated as urinary mutagens because: (i) they produce frameshift mutations in Salmonella typhimurium strains, (ii) they are easily extractable with blue cotton and (iii) their mutagenicity is abolished by a nitrite treatment procedure for deamination. PMID:2387016

  9. Contribution of soil-32P, fertilizer-32P and VA mycorrhizal fungi to phosphorus nutrition of corn plant

    32P labelled fertilizer and five synthetic phosphates (dicalcium phosphate, octocalcium phosphate, iron phosphate, aluminium phosphate and apatite), which were used to simulate inorganic phosphates such as Ca2-P, Ca8-P, FeP, Al-P and Ca10-P in calcareous soil, were applied to corn plants inoculating with and without vesicular-arbuscular (VA) mycorrhizal fungi in a calcareous soil. The results showed that VA mycorrhizal fungi and dicalcium phosphate, octocalcium phosphate, iron phosphate, aluminium phosphate promoted growth and increased phosphorus content of corn plant. The four synthetic phosphates except apatite had higher contributions to corn plant growth than VA mycorrhizal fungi. Contributions of fertilizer-P, soil-P and synthetic phosphates to phosphorus nutrition of corn plant were in order of synthetic phosphates (except apatite) > soil- P > fertilizer-P. Inoculating with VA mycorrhizal fungi increased the contribution of soil-P and decreased the contribution of synthetic phosphates, but did not affect the contribution of fertilizer-P

  10. Brachytherapy on restenosis. {sup 32}P radioisotope in animal model

    Bergoc, R.; Rivera, E.; Cocca, C.; Martin, G.; Cricco, G. [Buenos Aires Univ. (Argentina). School of Pharmacy and Biochemistry; Croci, M.; Guzman, L.

    2000-05-01

    Despite a notorious decline in age-adjusted death rates for cardiovascular pathologies, coronary artery disease still remains as the main cause of mortality above the age of 40 in men and 60 in women. More than 25% of death in persons over the age of 35 are due to coronary disease. In about 50% of men and 30% of women, the first manifestation of the disease is an acute myocardial infarction and 10% a sudden cardiac death. In Argentina it is estimated that in 1998 about 100.000-115.000 people suffered as first manifestation of coronary illness a myocardial acute infarct. Angioplasty has an important and well established site in the treatment of the coronary illness and restenosis represents the principal complication of this method for myocardial re-vascularization. About a 35-40% of treated arteries present restenosis within the first six month the intervention with the concomitant need of re-interventions, re-hospitalizations, by-pass surgery, work discontinuity and the high cost for the health system. A number of drugs were tested as anti-restenosis: anticoagulants, aspirin, antispasmodics and lipid-lowering agents but none was clearly efficient; also, experimental studies in which intravascular irradiation with different source types and energies, radiation doses and doses rate to prevent restenosis was utilized; however, there is no consensus in many aspects of this intravascular brachytherapy. The first step in this work was to induce the experimental model in rabbits. Afterwards, by means of the balloon methodology and stent implantation, brachytherapy experiments were carried out to evaluate the biological effect on different layers of arteries, with different Doses using a beta particle emitting radioisotope ({sup 32}P). The arteriosclerotic lesions were induced in New Zealand rabbits through the administration of a diet with high cholesterol content. Angioplastic interventions on femoral arteries were done with balloon methodology and controlled by

  11. Brachytherapy on restenosis. 32P radioisotope in animal model

    Despite a notorious decline in age-adjusted death rates for cardiovascular pathologies, coronary artery disease still remains as the main cause of mortality above the age of 40 in men and 60 in women. More than 25% of death in persons over the age of 35 are due to coronary disease. In about 50% of men and 30% of women, the first manifestation of the disease is an acute myocardial infarction and 10% a sudden cardiac death. In Argentina it is estimated that in 1998 about 100.000-115.000 people suffered as first manifestation of coronary illness a myocardial acute infarct. Angioplasty has an important and well established site in the treatment of the coronary illness and restenosis represents the principal complication of this method for myocardial re-vascularization. About a 35-40% of treated arteries present restenosis within the first six month the intervention with the concomitant need of re-interventions, re-hospitalizations, by-pass surgery, work discontinuity and the high cost for the health system. A number of drugs were tested as anti-restenosis: anticoagulants, aspirin, antispasmodics and lipid-lowering agents but none was clearly efficient; also, experimental studies in which intravascular irradiation with different source types and energies, radiation doses and doses rate to prevent restenosis was utilized; however, there is no consensus in many aspects of this intravascular brachytherapy. The first step in this work was to induce the experimental model in rabbits. Afterwards, by means of the balloon methodology and stent implantation, brachytherapy experiments were carried out to evaluate the biological effect on different layers of arteries, with different Doses using a beta particle emitting radioisotope (32P). The arteriosclerotic lesions were induced in New Zealand rabbits through the administration of a diet with high cholesterol content. Angioplastic interventions on femoral arteries were done with balloon methodology and controlled by fluoroscopy

  12. 3H-Penciclovir (3H-PCV) Uptake Assay

    Sekar, Thillai V; Paulmurugan, Ramasamy

    2016-01-01

    Thymidine Kinase from human Herpes simplex virus type 1 (HSV1-TK) in combination with specific substrate prodrug nucleotide analogue ganciclovir (GCV) has been widely used as suicidal therapeutic gene for cancer gene therapy. HSV1, and its mutant (HSV1-sr39TK) with improved substrate specificity, were used as reporter genes for PET-imaging of various biological functions in small animals, by combining with radiolabeled substrates such as 18F-FHBG and 124I-FIAU. 3H-Penciclovir (PCV) uptake assay is a method of choice used to determine the expression level of HSV1-TK in mammalian cells and tissues. HSV1-TK phosphorylate PCV and result in the formation of penciclovir monophosphate, and its subsequent phopsphorylation by cellular TK lead to the formation of penciclovir triphosphate, which is trapped selectively in cells expressing HSV-TK. 3H-Penciclovir enables the detection of penciclovir uptake of mammalian cells and tissues by radioactive procedures such as scintillation counting. Here we describe the protocol to carry out 3H-Penciclovir uptakes in mammalian cells.

  13. 14C Carbofuran residue in rice-fish ecosystem model

    14-C-carbofuran in the form of 14-C-Furada 3G was applied with doses of 0, 2, and 4 g/m2 to a rice-fish ecosystem model consisting of water, soil, rice, plant, and fish (Cyprinus carpio) in tanks of the size 1 m length, 1 m width, and 0.5 m depth. 14-C-carbofuran was released from 14-C-Furadan 3G, entered into the water, absorbed by plant root, and then distributed into the whole plant. A part of the 14-C-carbofuran was absorbed and retained by soil. In both doses of 4 and 2 g/m2, the 14-C-Furadan 3G was toxic to Cyprinus carpio under this experiment condition. (author). 5 refs, 5 figs, 6 tabs

  14. Transfer of 14C to prenatal and neonatal rats from their mothers exposed to 14C compounds by ingestion

    The transfer of 14C through placenta or milk was investigated and the radiation dose to fetal and newborn rats was estimated. Female rats at gestational stages or after delivery were exposed to 14C in the form of sodium bicarbonate, thymidine and lysine by a single ingestion. Radioactivity in maternal tissues and conceptuses (placenta, fetal membrane and fetus) and in the newborn was determined at various times after ingestion. After exposure to these 14C compounds, there was no significant difference between the 14C concentration in the fetus and that in the maternal tissues, suggesting that the placenta has no effect in preventing or accelerating the placental transfer of 14C. The concentration and content of 14C in the fetus and newborn were, however, dependent on the chemical form of 14C and on the prenatal or neonatal stage at the time of ingestion. The result of the dose estimation showed that 14C-lysine gave significantly higher prenatal and neonatal doses than 14C-sodium bicarbonate or 14C-thymidine. (author)

  15. Distribution of [14C]-tofenacine in rat brain after intravenous, intraperitoneal and multiple oral dosage

    The distribution of radioactivity in the rat brain at 5 min after 10 mg/kg of 14C-labelled N-methyl-2[(omethyl-a-phenylbenzyl)oxy]ethylamine, [14C]-tofenacine-hydrochloride, the active constituent of Elamolsup(R) and Tofacinesup(R), i.v. showed a heterogeneous pattern correlating well with what is known about perfusion and capillarization of brain areas. With the passage of time total brain radioactivity decreased rapidly and radioactivity was redistributed. Both processes occurred simultaneously so that a nearly homogeneous pattern was found at 1 h after i.v. administration. The outer layers of the hippocampus were then the only brain areas with a higher concentration of radioactivity. On i.p. administration of 25 mg/kg of [14C]-tofenacine-hydrochloride maximum brain radioactivity was observed at 30 min, the distribution pattern resembling that seen at 5 min after i.v. dosage. Its further time course corresponded to that of the i.v. series. On multiple oral administration of [14C]-tofenacine-hydrochloride (4 doses of 25 mg/kg at 3-h intervals), maximal radioactivity in the rat brain was observed at 120 min after the last dose. Again the distribution was heterogeneous. A model comprising a central compartment and twob brain compartments, representing areas of high and low perfusion, respectively, allows a quantitative explanation of the phenomena observed. (orig./GSE)

  16. Design and bioevaluation of a 32P-patch for brachytherapy of skin diseases

    The purpose of this study was to design and evaluate a 32P patch for brachytherapy of skin diseases. We employed Phosphoric-32P-acid and Chromic 32P-phosphate in combination with natural rubber or silicone to produce the patches. Stability studies in vitro to evaluate the leakage of radioactivity, autoradiographic studies to evaluate homogeneity and shielding, as well as therapeutic efficacy in an animal model of skin cancer of the selected 32P patch were performed. The 32P-silicone-patch demonstrated its safety for external application. Tumor growth was arrest and complete regressions of tumors were seen in some other cases with 40 Gy applied in a single-dose scheme. In conclusion, the 32P-silicone-patch is easy to prepare and use in the treatment of skin diseases

  17. Design and bioevaluation of a {sup 32}P-patch for brachytherapy of skin diseases

    Salgueiro, M.J. [Radioisotope Laboratory, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires (Argentina)], E-mail: jsalgueiro@ffyb.uba.ar; Duran, H. [Radiobiology Department, National Atomic Energy Commission (CNEA) Buenos Aires, CONICET and School of Science and Technology, University of San Martin, San Martin (Argentina); Palmieri, M. [Biodiversity and Experimental Biology Department, School of Exact and Natural Sciences, University of Buenos Aires, Buenos Aires (Argentina); Pirchio, R. [Dosimetry Department, National Atomic Energy Commission (CNEA) Buenos Aires (Argentina); Nicolini, J.; Ughetti, R. [Research and Development Department, Laboratorios Bacon SAIC (Argentina); Papparella, M.L. [Pathology Department, School of Dentistry, University of Buenos Aires, Buenos Aires (Argentina); Casale, G. [Research and Development Department, Laboratorios Bacon SAIC (Argentina); Zubillaga, M. [Radioisotope Laboratory, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires (Argentina)

    2008-03-15

    The purpose of this study was to design and evaluate a {sup 32}P patch for brachytherapy of skin diseases. We employed Phosphoric-{sup 32}P-acid and Chromic {sup 32}P-phosphate in combination with natural rubber or silicone to produce the patches. Stability studies in vitro to evaluate the leakage of radioactivity, autoradiographic studies to evaluate homogeneity and shielding, as well as therapeutic efficacy in an animal model of skin cancer of the selected {sup 32}P patch were performed. The {sup 32}P-silicone-patch demonstrated its safety for external application. Tumor growth was arrest and complete regressions of tumors were seen in some other cases with 40 Gy applied in a single-dose scheme. In conclusion, the {sup 32}P-silicone-patch is easy to prepare and use in the treatment of skin diseases.

  18. Incorporation of [3H]Leucine and [3H]Valine into Protein of Freshwater Bacteria: Uptake Kinetics and Intracellular Isotope Dilution

    Jørgensen, Niels O. G.

    1992-01-01

    Incorporation of [3H]leucine and [3H]valine into proteins of freshwater bacteria was studied in two eutrophic lakes. Incorporation of both amino acids had a saturation level of about 50 nM external concentration. Only a fraction of the two amino acids taken up was used in protein synthesis. At 100 nM, the bacteria respired 91 and 78% of leucine and valine taken up, respectively. Respiration of 3H and 14C isotopes of leucine gave similar results. Most of the nonrespired leucine was recovered i...

  19. Low-level 14C methane oxidation rate measurements modified for remote field settings

    Pack, M. A.; Pohlman, J.; Ruppel, C. D.; Xu, X.

    2012-12-01

    Aerobic methane oxidation limits atmospheric methane emissions from degraded subsea permafrost and dissociated methane hydrates in high latitude oceans. Methane oxidation rate measurements are a crucial tool for investigating the efficacy of this process, but are logistically challenging when working on small research vessels in remote settings. We modified a low-level 14C-CH4 oxidation rate measurement for use in the Beaufort Sea above hydrate bearing sediments during August 2012. Application of the more common 3H-CH4 rate measurement that uses 106 times more radioactivity was not practical because the R/V Ukpik cannot accommodate a radiation van. The low-level 14C measurement does not require a radiation van, but careful isolation of the 14C-label is essential to avoid contaminating natural abundance 14C measurements. We used 14C-CH4 with a total activity of 1.1 μCi, which is far below the 100 μCi permitting level. In addition, we modified field procedures to simplify and shorten sample processing. The original low-level 14C-CH4 method requires 6 steps in the field: (1) collect water samples in glass serum bottles, (2) inject 14C-CH4 into bottles, (3) incubate for 24 hours, (4) filter to separate the methanotrophic bacterial cells from the aqueous sample, (5) kill the filtrate with sodium hydroxide (NaOH), and (6) purge with nitrogen to remove unused 14C-CH4. Onshore, the 14C-CH4 respired to carbon dioxide or incorporated into cell material by methanotrophic bacteria during incubation is quantified by accelerator mass spectrometry (AMS). We conducted an experiment to test the possibility of storing samples for purging and filtering back onshore (steps 4 and 6). We subjected a series of water samples to steps 1-3 & 5, and preserved with mercuric chloride (HgCl2) instead of NaOH because HgCl2 is less likely to break down cell material during storage. The 14C-content of the carbon dioxide in samples preserved with HgCl2 and stored for up to 2 weeks was stable

  20. Incorporation of 14C in chemical constituents of algal cells

    Two marine algal species Dunaliella premodecta, Chlamydemonas sp. and one fresh water species Scenedesmus obliquus were studied for 14C incorporation under laboratory conditions. The uptake of 14C in dry marine algal species was found to be more compared to that in fresh water species for the same initial concentration in the respective media. A sequential extraction technique was employed to study the distribution of 14C in different organic constituents. 14C fixation was found to be more in fatty acid fractions followed by protein and nucleoprotein fraction. (author). 13 refs., 2 tabs

  1. Bound residues of 14C-carbofuran in soil

    Mineralization of 14C-carbofuran (2,3 dihydro-2,2-dimethyl-7-benzofuranyl-methylcarbamate) to 14CO2 as well as the formation of extractable and bound 14C-residues in clay loam soil were investigated under laboratory conditions. The 14C-carbofuran rapidly mineralized to 14CO2 and, after 20 days of incubation, 35.6% of the applied 14C was lost as 14CO2. The steady decrease of extractable 14C-residues was accomplished by a corresponding increase of bound 14C-residues over a 20-day incubation period. At the end of the experiment, the extractable and bound 14C-residues amounted to 7% and 59%, respectively, of applied radiocarbon. The soil containing bound 14C-residues was fractionated into humic substances. The humic acid, fulvic acid and humin fractions contained 22.39%, 26.04% and 17.56%, respectively, of the applied radiocarbon. The amount of 14C in microbial biomass was 15%. (author)

  2. Structure of T=2 24Ne from 14C on 14C

    The 14C(14C,α) reaction at 22 MeV was used to study T=2 24Ne. Charged particles were detected with a Si detector telescope at 0 deg., and γ transitions in coincidence were detected with an array of three Compton-suppressed 'clover' detectors and seven Compton-suppressed single Ge crystals. The α-γ and α-γ-γ coincidence data were analyzed to study the structure of 24Ne. Twenty-two new γ lines were assigned to 14 new levels. Angular distribution measurements provided spin assignments and restrictions to a number of levels. Likely candidates were found for the lowest 5+ and 6+ levels. All but one of the 12 states predicted to lie below 6 MeV by shell model calculations using the universal s-d interaction were observed. The rms deviation in excitation energies among these is 190 keV, and there is a tendency for the observed levels to lie somewhat higher than the predicted ones. A comparison of the structure of 24Ne with its neighbors suggests a significant shell gap above the νd5/2 orbital in agreement with the large d5/2-s1/2 gap implied by the effective single-particle energies in the universal s-d shell model interaction

  3. Behaviour of 14C-sulfadiazine and 14C-difloxacin during manure storage

    The persistence of sulfadiazine, difloxacin, and their metabolites has been investigated in stored manure. The manure collected from sulfadiazine (14C-SDZ) and difloxacin (14C-DIF) treated pigs contained N-acetylsulfadiazine (Ac-SDZ), 4-hydroxy-SDZ (4-OH-SDZ), and sarafloxacin (SARA) as the main metabolites, respectively along with their parent compounds. Manures were stored separately at 10 oC and 20 oC at various moisture levels. About 96-99% of the radioactivity remained in extractable parent compounds and their metabolites after 150 d of storage. The formation of non-extractable residue and the rate of mineralization were both negligible in manure containing SDZ and DIF. During storage SDZ concentration increased as a result of the deacetylation of Ac-SDZ, whose concentration decreased proportionally. Hence the environmental effects may be underestimated if the parent compound alone is considered for environmental risk assessment. About 11% and 14% of 4-OH-SDZ were lost after 20 and 40 d of storage; thereafter its concentration increased relatively, highlighting hydroxylation of SDZ. DIF degraded very slowly (7% loss after 150 d) during the storage of manure; in contrast the concentration of SARA decreased rapidly (72-90% loss after 150 d). Dilution of manure and storage at higher temperatures for a reasonable period of time enhanced the rate of reactions of SDZ, DIF and their related metabolites.

  4. Behaviour of (14)C-sulfadiazine and (14)C-difloxacin during manure storage.

    Lamshöft, Marc; Sukul, Premasis; Zühlke, Sebastian; Spiteller, Michael

    2010-03-01

    The persistence of sulfadiazine, difloxacin, and their metabolites has been investigated in stored manure. The manure collected from sulfadiazine ((14)C-SDZ) and difloxacin ((14)C-DIF) treated pigs contained N-acetylsulfadiazine (Ac-SDZ), 4-hydroxy-SDZ (4-OH-SDZ), and sarafloxacin (SARA) as the main metabolites, respectively along with their parent compounds. Manures were stored separately at 10 degrees C and 20 degrees C at various moisture levels. About 96-99% of the radioactivity remained in extractable parent compounds and their metabolites after 150d of storage. The formation of non-extractable residue and the rate of mineralization were both negligible in manure containing SDZ and DIF. During storage SDZ concentration increased as a result of the deacetylation of Ac-SDZ, whose concentration decreased proportionally. Hence the environmental effects may be underestimated if the parent compound alone is considered for environmental risk assessment. About 11% and 14% of 4-OH-SDZ were lost after 20 and 40d of storage; thereafter its concentration increased relatively, highlighting hydroxylation of SDZ. DIF degraded very slowly (7% loss after 150d) during the storage of manure; in contrast the concentration of SARA decreased rapidly (72-90% loss after 150d). Dilution of manure and storage at higher temperatures for a reasonable period of time enhanced the rate of reactions of SDZ, DIF and their related metabolites. PMID:20022355

  5. Behaviour of {sup 14}C-sulfadiazine and {sup 14}C-difloxacin during manure storage

    Lamshoeft, Marc; Sukul, Premasis; Zuehlke, Sebastian [Institute of Environmental Research (INFU), TU Dortmund, Otto-Hahn-Strasse 6, D-44227 Dortmund (Germany); Spiteller, Michael, E-mail: M.Spiteller@infu.uni-dortmund.de [Institute of Environmental Research (INFU), TU Dortmund, Otto-Hahn-Strasse 6, D-44227 Dortmund (Germany)

    2010-03-01

    The persistence of sulfadiazine, difloxacin, and their metabolites has been investigated in stored manure. The manure collected from sulfadiazine ({sup 14}C-SDZ) and difloxacin ({sup 14}C-DIF) treated pigs contained N-acetylsulfadiazine (Ac-SDZ), 4-hydroxy-SDZ (4-OH-SDZ), and sarafloxacin (SARA) as the main metabolites, respectively along with their parent compounds. Manures were stored separately at 10 {sup o}C and 20 {sup o}C at various moisture levels. About 96-99% of the radioactivity remained in extractable parent compounds and their metabolites after 150 d of storage. The formation of non-extractable residue and the rate of mineralization were both negligible in manure containing SDZ and DIF. During storage SDZ concentration increased as a result of the deacetylation of Ac-SDZ, whose concentration decreased proportionally. Hence the environmental effects may be underestimated if the parent compound alone is considered for environmental risk assessment. About 11% and 14% of 4-OH-SDZ were lost after 20 and 40 d of storage; thereafter its concentration increased relatively, highlighting hydroxylation of SDZ. DIF degraded very slowly (7% loss after 150 d) during the storage of manure; in contrast the concentration of SARA decreased rapidly (72-90% loss after 150 d). Dilution of manure and storage at higher temperatures for a reasonable period of time enhanced the rate of reactions of SDZ, DIF and their related metabolites.

  6. Determination of phagocytosis of 32P-labeled Staphylococcus aureus by bovine polymorphonuclear leukocytes

    A procedure for the measurement of phagocytosis by bovine polymorphonuclear leukocytes (PMN) of 32P-labeled Staphylococcus aureus was modified so that a larger number of samples could be compared in a single run, and smaller volumes of sample, PMN, and 32P-labeled S aureus could be used. Results were highly reproducible, with a coefficient of variation between duplicate determinations of less than or equal to 2%. Lysostaphin was prepared from the supernatant of S staphylolyticus and was compared with a commercially available preparation. Effects of lysostaphin on PMN and influence of incubation media on release of 32P from 32P-labeled S aureus by lysostaphin were examined

  7. The 32P test and other methods in the diagnosis of intraocular tumours

    Why the 32P test was reintroduced into The Netherlands for the diagnosis of intraocular tumours and how the present study was started is explained. The physical features of 32P and the biochemical behaviour of radioactive phosphate in healthy and neoplastic tissue are described. The complications, which can be encountered after the administration of 32P, are mentioned. A review of the 32P test in ophthalmology is given, with special attention to the methods used and the development of instruments for the measurements. The way in which the 32P test was performed in this study is described. The 32P test results obtained in the patients of this study are described. A good diagnostic accuracy of the 32P test was present in the 192 lesions located in the posterior segment, with a correct result obtained in 186 patients. Only three malignant and three benign lesions showed an incorrect test result. The results obtained with scintigraphy, fluorescein angiography, perimetry, transillumination, and ultrasonography are given and compared with data in the literature. The value of fluorescein angiography, perimetry, and the 32P test for the diagnosis of various lesions, with relevance to the differential diagnosis of a choroidal tumour, is described. The 32P tests performed in 12 patients with an extraocular lesion are mentioned. (Auth.)

  8. Synthesis of [3-14C]-L-tryptophan and 5'-hydroxy-[3-14C]-L-tryptophan

    The synthesis of selectively labeled [3-14C]-L-tryptophan and its derivative 5'-hydroxy-[3-14C]-L-tryptophan using chemical and multienzymatic methods is reported. The key intermediate for this synthesis, 3-14C]-DL-alanine was obtained from 14CH3I as a result of its condensation with N- (diphenylmethylene)glycine tert-butyl ester. Next, the mixture containing [3-14C]-DL-alanine, indole or 5-hydroxyindole has been converted to [3-14C]-L-tryptophan or 5'-hydroxy-[3-14C]-L-tryptophan, respectively, in a one-pot multienzymatic reaction using four enzymes: -amino acid oxidase, catalase, glutamic-pyruvic transaminase and tryptophanase. (author)

  9. [14C]-Sucrose uptake by guard cell protoplasts of pisum sativum, argenteum mutant

    Guard cells rely on import for their supply with reduced carbon. The authors tested by silicone oil centrifugation the ability of guard cell protoplasts to accumulated [14C]-sucrose. Uptake rates were corrected after measurement of 14C-sorbitol and 3H2O spaces. Sucrose uptake followed biphasic kinetics, with a high-affinity component below 1 mM external sucrose (apparent Km 0.8 mM at 25C) and a low-affinity nonsaturable component above. Uptake depended on pH (optimum at pH 5.0). Variations in the concentrations of external KCl, CCCP, and valinomycin indicated that about one-half of the sucrose uptake rate could be related to an electrochemical gradient across the plasmalemma. Total uptake rates measured at 5 mM external sucrose seem to be sufficient to replenish emptied plastids with starch within a few hours

  10. Production of 14C-labeled gas in BACTEC Neisseria Differentiation kits by Neisseria cinerea

    Six strains of Neisseria cinerea were tested in BACTEC Neisseria Differentiation kits (Johnston Laboratories, Inc., Towson, Md.), and all yielded positive glucose growth indices and negative maltose and fructose growth indices. These results were similar to those achieved with Neisseria gonorrhoeae. However, most of the N. cinerea isolates tested yielded 3-h glucose growth indices that were lower than those obtained with gonococci. 14C-labeled gas was produced significantly faster by N. gonorrhoeae than by N. cinerea. Additional studies suggested that the 14C-labeled gas produced by N. cinerea was carbon dioxide. N. cinerea strains were similar to Branhamella catarrhalis strains because both species failed to produce detectable acid from glucose, maltose, sucrose, fructose, and lactose in cysteine-tryptic agar media. However, in contrast to N. cinerea strains, B. catarrhalis strains did not metabolize glucose in BACTEC Neisseria Differentiation kits

  11. Root-uptake of {sup 14}C derived from acetic acid and {sup 14}C transfer to rice edible parts

    Ogiyama, Shinichi [Office of Biospheric Assessment for Waste Disposal, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba-shi 263-8555 (Japan)], E-mail: ogiyama@nirs.go.jp; Suzuki, Hiroyuki [Graduate School of Pharmaceutical Sciences, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba-shi 263-5522 (Japan); Inubushi, Kazuyuki [Graduate School of Horticulture, Chiba University, 648 Matsudo, Matsudo-shi 271-8510 (Japan); Takeda, Hiroshi; Uchida, Shigeo [Office of Biospheric Assessment for Waste Disposal, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba-shi 263-8555 (Japan)

    2010-02-15

    Three types of culture experiments using paddy rice (Oryza sativa L.) were performed to examine root-uptake of {sup 14}C in the form of acetic acid: double pot experiment (hydroponics), wet culture experiment (submerged sand medium), and chamber experiment (hydroponics and submerged sand medium). The {sup 14}C radioactivity in the plant, mediums, and atmospheric carbon dioxide ({sup 14}CO{sub 2}) in the chamber were determined, and the distribution of {sup 14}C in the plant was visualized using autoradiography. In the double pot experiment, the shoot of the plant and the lower root which was soaked in the culture solution had {sup 14}C radioactivity, but the upper root which did not have contact with the solution had none. There were also {sup 14}C radioactivity in the grains and roots in the wet culture experiment. Results of the chamber experiment showed that {sup 14}CO{sub 2} gas was released from the culture solution in both types of cultures. Results indicated that the {sup 14}C-acetic acid absorbed by rice plant through its root would be very small. Most of the {sup 14}C-acetic acid was transformed into gaseous forms either in the culture solution or rhizosphere. A relatively longer time would be needed to assimilate {sup 14}C derived from acetic acid to grain parts after it was once absorbed by the shoot through the root. Availability of {sup 14}C for the plant in sand culture was considered to be decreased compared with that for the plant in the hydroponics experiment. It was suggested that rice plant absorbed and assimilated {sup 14}C through the plant roots not because of uptake of {sup 14}C-acetic acid but because of uptake of {sup 14}C in gaseous forms such as {sup 14}CO{sub 2}.

  12. Root-uptake of 14C derived from acetic acid and 14C transfer to rice edible parts

    Three types of culture experiments using paddy rice (Oryza sativa L.) were performed to examine root-uptake of 14C in the form of acetic acid: double pot experiment (hydroponics), wet culture experiment (submerged sand medium), and chamber experiment (hydroponics and submerged sand medium). The 14C radioactivity in the plant, mediums, and atmospheric carbon dioxide (14CO2) in the chamber were determined, and the distribution of 14C in the plant was visualized using autoradiography. In the double pot experiment, the shoot of the plant and the lower root which was soaked in the culture solution had 14C radioactivity, but the upper root which did not have contact with the solution had none. There were also 14C radioactivity in the grains and roots in the wet culture experiment. Results of the chamber experiment showed that 14CO2 gas was released from the culture solution in both types of cultures. Results indicated that the 14C-acetic acid absorbed by rice plant through its root would be very small. Most of the 14C-acetic acid was transformed into gaseous forms either in the culture solution or rhizosphere. A relatively longer time would be needed to assimilate 14C derived from acetic acid to grain parts after it was once absorbed by the shoot through the root. Availability of 14C for the plant in sand culture was considered to be decreased compared with that for the plant in the hydroponics experiment. It was suggested that rice plant absorbed and assimilated 14C through the plant roots not because of uptake of 14C-acetic acid but because of uptake of 14C in gaseous forms such as 14CO2.

  13. The use of 14C ethanolamine as a precursor

    Two new 2 chloroethyl nitrosoureas were labelled on two positions by 14C starting from Na14CN and using 14C ethanolamine as intermediate, i.e. on the carbon 2 of the 2 chloro ethyl group and on the carbon 2 of the cysteamine part. (author)

  14. Application of AMS 14C measurements to criminal investigations

    14C variations of atmospheric CO2 as well as carbonaceous fraction of living materials, such as collagen from tooth and bone, tissue, skin, hair, nail, etc., of modern humans are influenced by 14C produced artificially by nuclear bomb tests in the atmosphere from late 1950s to early 1960s. By careful investigation of 14C concentration of tree rings and human body samples formed in this time intervals, we can establish a relationship of their 14C concentrations with calendar year. By applying this relation to a sample whose 14C concentration can be measured, we can estimate the formation age of the sample. In addition, sources of the chemicals that were used in some criminal cases can be possibly identified, by their carbon isotope ratios (13C/12C and 14C/12C). This method of age determination has been applied to a forensic study, i.e., two criminal cases of murder. For each case, by comparing the measured 14C abundances of several pieces of hair and one tooth (the third molar) from the body with the annual change on concentrations of bomb-produced 14C, the time of death of the body and the age of the victim were estimated. The estimated values were consistent with the real ones that were revealed by the confession of the real murderers. (author)

  15. Rectal absorption of homatropine [14C] methylbromide in the rat

    Homatropine [14C]methylbromide (HMB-14C) was administered to rats by intramuscular injection, oral gavage and rectal suppository. Plasma concentrations of 14C were measured over the subsequent 12 h. Peak plasma concentrations were higher and achieved more rapidly after rectal administration than by other routes whether HMB-14C was administered in a water-soluble suppository base or in aqueous solution. Twelve h after the suppositories were inserted and retained 28% of the 14C had been excreted in the urine while 56% remained in the large intestine. Unlabelled HMB, given in rectal suppositories to anaesthetized rats, caused prompt blockade of the effects of vagal stimulation on pulse rate and of intravenous acetylcholine on blood pressure. These results confirm the rapid rectal absorption of the drug. (author)

  16. Radiocarbon 14C differentiation of sparkling and carbonated wines

    Specific 14C-activities, percent of modern 14C-activity, and calculated percent of fermentation CO2 are presented for CO2 contained in commercial sparkling wines, labeled as champagne or produced by the bulk (charmat) process. These data are given for the production years 1976-1982. The survey encompassed effervescent wines produced in Spain, Italy, West Germany, California, and New York. Addition of synthetic CO2 to approximately 40 samples represented as sparkling wines was indicated by low 14C-activities of CO2 in these wines. Data for 14C-activity were also presented for the ethanol distilled from sparkling wines for the years 1977-1980. In all cases, the 14C-activity of ethanol was appropriate to the year of vintage

  17. Percutaneous absorption of [14C]DDT and [14C]benzo[a]pyrene from soil

    The objective was to determine percutaneous absorption of DDT and benzo[a]pyrene in vitro and in vivo from soil into and through skin. Soil (Yolo County 65-California-57-8; 26% sand, 26% clay, 48% silt) was passed through 10-, 20-, and 48-mesh sieves. Soil then retained by 80-mesh was mixed with [14C]-labeled chemical at 10 ppm. Acetone solutions at 10 ppm were prepared for comparative analysis. Human cadaver skin was dermatomed to 500 microns and used in glass diffusion cells with human plasma as the receptor fluid (3 ml/hr flow rate) for a 24-hr skin application time. With acetone vehicle, DDT (18.1 +/- 13.4%) readily penetrated into human skin. Significantly less DDT (1.0 +/- 0.7%) penetrated into human skin from soil. DDT would not partition from human skin into human plasma in the receptor phase (less than 0.1%). With acetone vehicle, benzo[a]pyrene (23.7 +/- 9.7%) readily penetrated into human skin. Significantly less benzo[a]pyrene (1.4 +/- 0.9%) penetrated into human skin from soil. Benzo[a]pyrene would not partition from human skin into human plasma in the receptor phase (less than 0.1%). Substantivity (skin retention) was investigated by applying 14C-labeled chemical to human skin in vitro for only 25 min. After soap and water wash, 16.7 +/- 13.2% of DDT applied in acetone remained absorbed to skin. With soil only 0.25 +/- 0.11% of DDT remained absorbed to skin. After soap and water wash 5.1 +/- 2.1% of benzo[a]pyrene applied in acetone remained absorbed to skin. With soil only 0.14 +/- 0.13% of benzo[a]pyrene remained absorbed to skin

  18. Impact of atmospheric 14C to the karst environment

    Naturally cosmic-ray produced radiocarbon 14C is a part of the CO2 cycle and through the atmosphere-biosphere-hydrosphere exchange process it has been introduced to the environment. Anthropogenic disturbance of the natural 14C activity caused by nuclear tests, nuclear power plants and also by fossil fuel combustion has been recorded in the atmospheric CO2. The karst environment including water, carbonate sediment and soil, where exchange processes within the CO2-HCO3 -CaCO3 system play an important role, is very sensitive to any change in the atmosphere and response to the contamination is very fast. 14C activity of atmospheric CO2 has been continuously measured in monthly samples in Zagreb area since 1983. Seasonal variations have been observed, as well as steady decrease of yearly mean values. Influence of fossil fuel combustion in the city area during winter months was also observed. Few examples of isotopic study in karst environment in Croatia and Slovenia will be presented: 1) The influence of atmospheric 14C activity to the recent carbonate precipitated in the surface water in form of tufa in the Plitvice Lakes, Korana, Krka and Zrmanja rivers in Croatia, and Krka river in Slovenia; 2) 14C activity in recent speleothems from several caves in Croatia and Postojna Cave in Slovenia; 3) Distribution of 14C activity in the surface soil in Plitvice Lakes and Postojna areas; 4) 14C activity of atmospheric CO2 inside and outside the Postojna Cave, 5) 14C activity in recent plants (aquatic and terrestrial) and shells. The stable isotopes δ 13C and δ 18O for some of the samples above will be presented too. Distribution of 14C in the karst environment will be discussed and compared with 14C activity of atmospheric CO2

  19. Radiophosphorus (/sup 32/P) treatment of bone marrow disorders in dogs: 11 cases (1970-1987)

    Smith, M.; Turrel, J.M.

    1989-01-01

    Between March 1970 and February 1987, radiophosphorus (/sup 32/P) was used to treat bone marrow disorders in 6 dogs; 4 had polycythemia vera and 2 had essential thrombocythemia. Activities of /sup 32/P given initially ranged from 2.4 to 3.3 mCi/m2. Four dogs responded well to /sup 32/P treatment, with gradual resolution of high RBC or platelet counts. Two of these dogs died of intercurrent disease unrelated to their bone marrow disorder, before blood counts could be stabilized. Two dogs did not respond to the initial /sup 32/P treatment nor to additional treatments with /sup 32/P, and had clinical signs and blood counts stabilized by use of phlebotomy or chemotherapeutic agents. We reviewed and analyzed 5 other cases of bone marrow disorders in dogs treated with /sup 32/P and included the findings from their records with the records of our 6 dogs in this retrospective analysis. Of the 8 dogs with polycythemia vera treated with /sup 32/P, 5 were given a single treatment that controlled clinical signs and blood counts for the remainder of the follow-up period. Of the 3 dogs treated for thrombocytosis with /sup 32/P, 2 had blood counts that responded to a single treatment.

  20. 14C-age tracers in global ocean circulation models

    Koeve, W.; Wagner, H.; Kähler, P.; Oschlies, A.

    2015-07-01

    The natural abundance of 14C in total CO2 dissolved in seawater (DIC) is a property applied to evaluate the water age structure and circulation in the ocean and in ocean models. In this study we use three different representations of the global ocean circulation augmented with a suite of idealised tracers to study the potential and limitations of using natural 14C to determine water age, which is the time elapsed since a body of water has been in contact with the atmosphere. We find that, globally, bulk 14C-age is dominated by two equally important components, one associated with ageing, i.e. the time component of circulation, and one associated with a "preformed 14C-age". The latter quantity exists because of the slow and incomplete atmosphere-ocean equilibration of 14C particularly in high latitudes where many water masses form. In the ocean's interior, preformed 14C-age behaves like a passive tracer. The relative contribution of the preformed component to bulk 14C-age varies regionally within a given model, but also between models. Regional variability in the Atlantic Ocean is associated with the mixing of waters with very different end members of preformed 14C-age. Here, variations in the preformed component over space and time mask the circulation component to an extent that its patterns are not detectable from bulk 14C-age. Between models, the variability of preformed 14C-age can also be considerable (factor of 2), related to the combination of physical model parameters, which influence circulation dynamics or gas exchange. The preformed component was found to be very sensitive to gas exchange and moderately sensitive to ice cover. In our model evaluation, the choice of the gas-exchange constant from within the currently accepted range of uncertainty had such a strong influence on preformed and bulk 14C-age that if model evaluation would be based on bulk 14C-age, it could easily impair the evaluation and tuning of a model's circulation on global and regional

  1. Helicobacter pylori infection studies using 14C UBT method

    Carbon 14 (14C) is a naturally occurring radioactive isotope of carbon. The half-life of 14C is about 5,730 years, and it decays by emitting a low energy beta (â) particle of mean energy 49 KeV. The biological half life of 14C is 10 to 12 days. 14C is present in the environment and in all organic materials and behaves in the environment in the same manner as other carbon isotopes. In medicine, 14C can be injected to study abnormalities of metabolism that underlie diabetes, gout, anaemia and acromegaly (adult 'gigantism'), and for diagnosis of Helicobacterpylori (H pylori), The discovery H Pylori by Warren and Marshall in 1982 changed the approach to treat peptic ulcer disease (PUD), Since then H pylori has been the focus of clinical research and debate. The causal relationship between H pylori infection and chronic gastritis is well established, H pylori infection is one of the most common human infections worldwide. This organism has been shown to infect over half of the world's population. By the application of radiation much progress has been made worldwide in the field of medicine. This article presents the application of 14C Urea Breath Test (14C UBT) for the diagnosis of the H pylori bacteria which present in the stomach and duodenum, 14C UBT relies on the urease activity of H pylori to detect the presence of active infection. Board of Radiation and Isotope Technology (BRIT), Mumbai has developed 14C UBT method and already in regular practice in many hospitals across the country. Orally administered 14C urea will be hydrolyzed into ammonia (NH4) and 14C labelled carbon dioxide (14CO2). The presence of a significant amount of (14CO2) in the exhaled breath indicates active H pylori infection. 14C UBT is relatively inexpensive, is easy to perform, and does not require endoscopy. 14C UBT has proved to be one of the most accurate methods for assessing H pylori status. The ionizing radiation dose involved in this test is extremely low, much lower than the

  2. Myo-inositol-14C, phytic acid-14C and ferric phytate-14C metabolism through microbian action in an andosol soil

    The myo-inositol-14C, phytic acid-14C and ferric phytate-14C compounds were incubated in an andosol soil at 70% of the field capacity and at 36.5 deg C during twelve days. These compounds suffered a microbian oxidation at 14CO2 of 61.0, 1.9 and 0% respectively. The fixation of the phytic acid-14C was observed through the fast decrease in the metabolism, due to the formation of complexes with the Fe and Al (phytates). The myo-inositol-14C metabolism was reduced by a factor of nine at the second incubation day. The following mechanisms were observed in the myo-inositol metabolism: (i) adsorption of the inositol by the soil minerals, (ii) adsorption by humic acids, (iii) myo-inositol phosphorylation and (iv) epimerization of myo-inositol to chiro-inositol. It was found that the (i) and (ii) formation depends on the soil microbian activity. The (i), (ii) and (iii) interactions were considered as possible mechanisms for the inhibition of the myo-inositol microbian oxidation. The inhibition of the myo-inositol oxidation through adsorption or phosphorylation is considered as a chemical blockade for the hydroaxial group, avoiding this way a microbian oxidation stereospecific of this hydroxil group. (author)

  3. Effects of Pseudomonas species on the release of bound 14C residues from soil treated with [14C]atrazine

    The release of bound (nonextractable) 14C residues from soil previously treated with [14C]atrazine was investigated by incubation of the solvent-extracted soil with two species of Pseudomonas capable of metabolizing atrazine. The two species, 192 and 194, released bound 14C residues from the soil. Addition of glucose, known to increase microbiological activities, to the incubated soil appeared to enhance the release of soil-bound 14C residues, in particular in the presence of Pseudomonas species 192. The 14C bound residues in soil, mainly present as the parent compound and its hydroxy and monodealkylated analogues, were released into the incubation mixture and were subsequently metabolized by the two species involving dechlorination and dealkylation

  4. Dating human DNA with the 14C bomb peak

    In 1963 the limited nuclear test ban treaty stopped nuclear weapons testing in the atmosphere. By then the addition from bomb-produced 14C had doubled the 14C content of the atmosphere. Through the CO2 cycle this excess exchanged with the hydrosphere and biosphere leading to a rapidly decreasing 14C level in the atmosphere. Today we are almost back to the pre-nuclear level. As a consequence all people on Earth who lived during the second half of the 20th century were exposed to this rapidly changing 14C signal. A few years ago, a group at the Department of Cell and Molecular Biology of the Karolinska Institute in Stockholm started to use the 14C bomb peak signal in DNA to determine retrospectively the age of cells from various parts of the human body (brain, heart, fat). In a collaboration with this group, we have studied the age of olfactory bulb neurons in the human brain. For this investigation, 14C AMS measurements were developed at VERA for very small carbon samples in the range from 2 to 4 micrograms. In the presentation the general concept of 14C bomb peak dating of human DNA and several applications are discussed.

  5. 14C in the deep water of the east Atlantic

    The renewal of east Atlantic deep water and its large-scale circulation and mixing have been studied in observed distributions of temperature, silicate, ΣCO2, and 14C. 14C variations in northeast Atlantic deep water below 3500m depth are small. Δ14C values range from - 100 per thousand to - 125 per thousand. 14C bottom water concentrations decrease from Δ14C = -117 per thousand in the Sierra Leone Basin to Δ14C = -123 per thousand in the Iberian Basin and are consistent with a mean northward bottom water flow. The characteristic of the water that flows from the west Atlantic through the Romanche Trench into the east Atlantic was determined by inspection of theta/Δ14C and theta/SiO2 diagrams. A mean potential temperature of theta = 1.50 +/- .050C was found for the inflowing water. A multi-box model including circulation, mixing, and chemical source terms in the deep water has been formulated. Linear programming and least-squares techniques have been used to obtain the transport and source parameters of the model from the observed tracer fields. Model calculations reveal an inflow through the Romanche Trench from the west Atlantic, which predominates over any other inflow (5 +/- 2) Sv (potential temperature 1.500C), a convective turnover of (150 +/- 50) years and a vertical apparent diffusivity of (4 +/- 1) cm2/s. Chemical source terms are in the expected ranges

  6. Aspects of the metabolism of U-14C arginine, U-14C histidine and U-14C lysine by adult female Glossina morsitans during pregnancy

    U-14C arginine, U-14C histidine or U-14C lysine was injected into haemolymph of pregnant female Glossina morsitans. Radioactivity was detected in the post-parturient female and its larval offspring mostly in arginine or histidine, but in the case of lysine injection radioactivity was detected in the two life stages in lysine lipids and a range of nonessential amino acids. The pattern of radioactivity in the developing oocyte and larva was related to growth characteristics of these young stages. Whereas arginine and histidine were mostly excreted unchanged, lysine derived radioactivity was detected in the excreted uric acid and expired carbon dioxide; radioactivity in such products was greater in early than late pregnancy. (author)

  7. Application of AMS 14C measurements to criminal investigations

    14C variations of atmospheric CO2 as well as carbonaceous materials of human body, such as collagen fractions from teeth and bone, tissue, hair, nail, etc., of modern humans dead or alive, are influenced by 14C produced artificially by nuclear bomb tests in the atmosphere from late 1950s to early 1960s. By careful investigation of 14C concentration of tree rings and human tissue samples formed in this time ranges, we can establish a relation between their 14C concentrations and calendar year. By applying this relation to a sample whose 14C concentration can be measured, we can estimate the formation age of the sample. In addition, sources of the drugs that were used in some criminal cases can be possibly identified by the analysis of their carbon isotope ratios (13C/12C and 14C/12C). This method of age determination was applied to a forensic study; i.e., to two similar cases of murder. One of the two cases is for a dead body of a modern human who was killed in 1978 and buried under the floor of the house owned by the murderer. The body was excavated in 2004 according to the confession by the murderer. 14C abundances of several pieces of hair and one tooth (the third molar) from the body were measured with accelerator mass spectrometry (AMS), and compared with the annual change on concentrations of bomb-produced 14C. The time of death of the body was estimated to be at around 1977, and her age was from 30 to 37 years old at that time. These estimations were consistent with the real values that were revealed after the case was solved by the confession of the real murderer who gave himself up to the police. For the other case, 14C analysis was also consistent with the fact revealed by police investigations as well as by the confession of the real murderer.

  8. Effects of chronic ethanol intake on metabolic conversions of 14C erucic acid by the livers of rat fed with rapeseed or ground nut oil

    The effects of addition of ethanol to diets containing rapeseed or ground nut oil on the metabolic conversion of 14 14C erudic and 9-10 3H oleic acid were studied in the rat liver. Whatever the diet more 14C than 3H radioactivity was recovered in liver lipids 2 and 19 hours after injection of labelled fatty acids. Ethanol has little effect on this incorporation. Only small amounts of 3H oleic acid were converted. In all cases, the metabolic conversion of erucic acid was identical: the main part of 14C was not recovered as erucic acid but was present in other mono unsaturated fatty acids n-9:oleic acid (18:1), which was the most labelled acid, 16:1, 20:1 and nervonic acid (24:1). The amount of erucic acid converted to shorter chain fatty acids was unchanged by addition of ethanol but the alcohol increased the proportion of 14C radioactivity recovered as nervonic acid. This latter effect was opposite to the effect of rapeseed oil diet, which consisted in a decrease in the conversion of erucic to nervonic acid. A high amount of 14C radioactivity was recovered in the F.F.A. fraction of the liver as an unknown compound (13 and 80% of 14C radioacitivty respectively after 2 and 19h). Its identification is presently under investigation

  9. 14C-carbaryl residues in cotton seed products

    14C-Methyl and 14C-ring-labelled carbaryl were used to study the magnitude and fate of the insecticide residues in cotton seed products and in the plant. 14C-Residues were found to be 0.08-0.09, 0.23-0.30 and 0.05 ppm in the seed, oil and cake respectively. In the oil, the residue was resolved into four compounds two of which were identified as carbaryl and 1-naphthol. Residues taken up from the soil did not exceed 0.3 ppm after the first week and declined to 0.1 ppm after five weeks. (author)

  10. Preparation of D-[U-14C]galactose and α-D-[U-14C]galactose-1-phosphate

    Optically pure D-[U-14C]galactose was prepared on a preparatory scale using the galactokinase enzyme. The suggested procedure allows to also prepare a α-D-[U-14C]galactose-1-phosphate and L-[U-14]galactose giving good yield. The experiments proved that the raw fraction isolated from yeast of the Kluyveromyces fragilis strain or the Kluyveromyces lactis strain shows sufficient activity. Phosphorylation of D-[U-14C]galactose practically terminates after 30 mins of incubation. DL-[U-14C]galactose isolated using preparatory paper chromatography from the acid hydrolyzate of [U-14C] polysaccharide is a satisfactory radioactive precursor. The developed preparation procedure theoretically contributed towards the further elucidation of the problem of the proportional representation of galactose stereo-isomers in extracellular polysaccharide isolated from red algae. In this respect data in the literature differ and some sources state a significantly higher propertion of L-galactose. The experiments showed that [U-14C] polysaccharide isolated from the red algae Porphyridium cruentum prevalently contains D-[U-14C]galactose, which confirms the process of enzyme reaction. (author). 1 tab., 4 refs

  11. 14C and tritium dynamics in wild mammals: a metabolic model

    The protection of biota from ionising radiations needs reliable predictions of radionuclide dynamics in wild animals. Data specific for many wild animals radionuclide combinations is lacking and a number of approaches including allometry have been proposed to address this. However, for 14C and tritium, which are integral components of animals tissues and their diets, a different approach is needed in the absence of experimental data. Here we propose a metabolically based model which can be parameterized predominantly on the basis of published metabolic data. We begin with a metabolic definition of the 14C and OBT loss rate (assumed to be the same) from the whole body and also specific organs, using available information on field metabolic rate and body composition. The mammalian body is conceptually partitioned into compartments (body water, viscera, adipose, muscle, blood and remainder) and a simple model defined using net maintenance and growth needs of mammals. Intake and excretion, and transfer to body water are modelled using basic metabolic knowledge and published relationships. The model is tested with data from studies using rats and sheep. It provides a reliable prediction for whole body and muscle activity concentrations without the requirement for any calibration specific to 3H and 14C. Predictions from the model for representative wild mammals (as selected to be reference organisms within international programmes) are presented. Potential developments of a metabolic model for birds and the application of our work to human food chain modelling are also discussed. (author)

  12. Evaluation of errors in the 14C method of primary production measurement

    Membrane filtration is an integral part of the 14C method of measuring primary productivity in natural waters. Polycarbonate, cellulose ester, and glass-fiber filters retan about 0.0003, 0.09, and 0.24 mg water per mm2 surface area. The [14C]bicarbonate in this retained water must be eliminated before the filter is assayed for radioactivity. Airdrying, desiccator-drying in the presence or absence of a CO2 absorbant, and oven-drying are only partially effective decontamination procedures; washing with pH 2 filtered lake water removes most of the contaminating activity. A plot (dpm.filter-1 vs. volume filtered) is used to diagnose the efficiency of decontamination. A simple and safe decontamination procedure is shown to eliminate effectively all residual [14C]bicarbonate activity. Membrane filters are placed in scintillation vials, 0.1 to 1.0 ml of 0.5 N HCl is added, and, after a 2 to 3-h interval, the scintillation fluor is added

  13. Residues of 14C-cyolane in cottonseed products

    The systemic insecticide cyolane [2-(0,0-diethylphosphoryl)-imino-1,3-dithiolane] was prepared from 14C-ethanol, phosphorus oxychloride and 2-amino-1,3-dithiolane. Cotton plants were treated with two applications of the insecticide under conditions of local agricultural practice. 14C-residues in the crude oil and cake of the harvested cotton seeds amounted to 1.63 and 0.014 mg/kg respectively. About 50% of the 14C-activity present in the crude oil was found to be eliminated by simulated commercial processes used for refining of the oil. Alkali treatment and bleaching removed 16% and 25% of the radioactive residues respectively. Winterization of the bleached oil at 5-70C for 3 days effected a further elimination of 13%. 14C-residues in the cotton seed products and in the samples of the refined oil were characterized and the main constituents identified using chromatographic techniques. (author)

  14. Determination of 14C content in fermentation alcohols

    The measuring of activity in 14C of ethylic alcohol permits to distinguish fermentation alcohol from synthetic alcohol. This activity is used to determine the corresponding percentages of these alcohols in cases of mixture

  15. Forensic applications of 14C bomb-pulse dating

    After a brief review of the basics of 14C bomb-pulse dating, this paper presents two unique forensic applications. Particular attention is dedicated to the use of the 14C bomb-pulse to establish the time of harvest of illicit drugs such as heroin and opium. Preliminary measurements of 14C concentrations in milligram samples taken from seized drugs are presented. 14C bomb-pulse dating can determine whether drug distribution originates from stockpiles or recent manufacture, and support the action of law enforcement authorities against criminal organisations involved in drug trafficking. In addition, we describe the dating of wine vintages for a number of authenticated single label vintage red wines from the Barossa Valley - South Australia. Our results show that radiocarbon dating can be used to accurately determine wine vintages and therefore reveal the addition of unrelated materials of natural and synthetic origin

  16. Forensic applications of 14C bomb-pulse dating

    Zoppi, U.; Skopec, Z.; Skopec, J.; Jones, G.; Fink, D.; Hua, Q.; Jacobsen, G.; Tuniz, C.; Williams, A.

    2004-08-01

    After a brief review of the basics of 14C bomb-pulse dating, this paper presents two unique forensic applications. Particular attention is dedicated to the use of the 14C bomb-pulse to establish the time of harvest of illicit drugs such as heroin and opium. Preliminary measurements of 14C concentrations in milligram samples taken from seized drugs are presented. 14C bomb-pulse dating can determine whether drug distribution originates from stockpiles or recent manufacture, and support the action of law enforcement authorities against criminal organisations involved in drug trafficking. In addition, we describe the dating of wine vintages for a number of authenticated single label vintage red wines from the Barossa Valley - South Australia. Our results show that radiocarbon dating can be used to accurately determine wine vintages and therefore reveal the addition of unrelated materials of natural and synthetic origin.

  17. Forensic applications of {sup 14}C bomb-pulse dating

    Zoppi, U. E-mail: ugo@ansto.gov.au; Skopec, Z.; Skopec, J.; Jones, G.; Fink, D.; Hua, Q.; Jacobsen, G.; Tuniz, C.; Williams, A

    2004-08-01

    After a brief review of the basics of {sup 14}C bomb-pulse dating, this paper presents two unique forensic applications. Particular attention is dedicated to the use of the {sup 14}C bomb-pulse to establish the time of harvest of illicit drugs such as heroin and opium. Preliminary measurements of {sup 14}C concentrations in milligram samples taken from seized drugs are presented. {sup 14}C bomb-pulse dating can determine whether drug distribution originates from stockpiles or recent manufacture, and support the action of law enforcement authorities against criminal organisations involved in drug trafficking. In addition, we describe the dating of wine vintages for a number of authenticated single label vintage red wines from the Barossa Valley - South Australia. Our results show that radiocarbon dating can be used to accurately determine wine vintages and therefore reveal the addition of unrelated materials of natural and synthetic origin.

  18. Determination of phagocytosis in periodontitis postjuvenilis using 14C

    In 20 patients with periodontitis and 10 healthy controls phagocytosis was determined using 14C-labelled Staphylococcus aureus. The decrease of phagocytosis found in the diseased patients was significant

  19. Effect of HF leaching on 14C dates of pottery

    This paper presents the experiments with 14C dating of two potsherds, which contained carbon dispersed rather homogeneously in their clay fabric. After AAA treatment, the potsherds still appeared to be contaminated with young carbon, presumably connected with humic acids. To make removal of humic acids more effective, we treated the sherds with HF acid of different concentration. The 14C results obtained demonstrate that HF treatment indeed helps to remove humic contaminants, but it also mobilizes carbon bound to raw clay, which may make 14C dates too old. We conclude therefore, that using a simple combination of HF and AAA treatment seems insufficient in reliable 14C dating of carbon homogeneously dispersed in the volume of potsherds.

  20. Patient risk of 14C-urea breath test

    Helicobacter Pylori bacteria infection is determined by activity measurement of the exhaled 14C-carbon dioxide formed from 14C-urea in stomach. About 37 kBq of capsulated 14C -urea is administered to the patient. Because 14C is a weak beta emitter, patients receive certain radiation dose. This could be the only drawback of this method. Because of that in this paper the effective dose has been determined. On that basis the patient risk has been estimated. The results show that the patient effective dose is at the level of the daily background radiation. So, from the radiation protection point of view this method is very safe. Including other excellent performances of the method like sensitivity, selectivity, noninvasivity, fastness and low costs, it could be recommended in diagnosis and eradication of Helicobacter Pylori infections. (author)

  1. 14C-age tracers in global ocean circulation models

    W. Koeve

    2014-10-01

    Full Text Available The natural abundance of 14C in total CO2 dissolved in seawater is a property applied to evaluate the water age structure and circulation in the ocean and in ocean models. In this study we use three different representations of the global ocean circulation augmented with a suite of idealised tracers to study the potential and limitations of using natural 14C to determine water age, the time elapsed since a body of water had contact with the atmosphere. We find that, globally, bulk 14C-age is dominated by two equally important components, one associated with aging, i.e. the time component of circulation and one associated with a "preformed 14C-age". This latter quantity exists because of the slow and incomplete atmosphere/ocean equilibration of 14C in particular in high latitudes where many water masses form. The relative contribution of the preformed component to bulk 14C-age varies regionally within a given model, but also between models. Regional variability, e.g. in the Atlantic Ocean is associated with the mixing of waters with very different end members of preformed 14C-age. In the Atlantic, variations in the preformed component over space and time mask the circulation component to an extent that its patterns are not detectable from bulk 14C-age alone. Between models the variability of age can also be considerable (factor of 2, related to the combinations of physical model parameters, which influence circulation dynamics, and gas exchange in the models. The preformed component was found to be very sensitive to gas exchange and moderately sensitive to ice cover. In our model evaluation exercise, the choice of the gas exchange constant from within the current range of uncertainty had such a strong influence on preformed and bulk 14C-age that if model evaluation would be based on bulk 14C-age it could easily impair the evaluation and tuning of a models circulation on global and regional scales. Based on the results of this study, we propose

  2. Transplacental and mammary passage of radioactivity in rats treated vaginally and orally with [14C]propranolol

    Single doses (10 mg/kg) of an aqueous solution of [14C]propranolol were administered either orally (po) or intravaginally (ivg) on gestational d 15, or on postpartum d 7-10. Upon ivg administration, [14C]propranolol was quickly transferred to systemic circulation and the mean blood [14C] concentrations were significantly greater during the first 0.25-2 h than in po dosed counterparts. About 98% of the ivg applied dose was absorbed after 6 h in gravid rats, and the combined 6-h excretions of radioactivity in the urine (ivg = 24.6%; po = 22.9%) and feces (ivg = 16.8%; po = 14.6%) were equivalent in both groups. At the end of 6 h, the levels of [14C] in the urinary bladder, adrenal, uterus, ovary, spleen, skeletal muscle, brain, heart, lung and fat were significantly higher in ivg treated rats than po dosed animals. Compared with the maternal plasma (ivg = 0.76; po = 0.88 microgram/ml), the mean concentrations of [14C] in the placentas were similar in both groups, while the amounts of [14C] were three to five times lower in the amniotic fluids and the fetuses of both po and ivg treated dams. In lactating rats, over 99% of the administered radioactivity was absorbed from the vagina within 6 h. The blood concentrations of [14C] were significantly elevated at 0.5 and 1 h in the per vaginam treated animals, and afterward the disappearance rate of [14C] followed a similar course in both groups. Following ivg application, the milk radioactivity peaked at 0.5 h and declined rapidly. However, the appearance of [14C] in milk was rather slow after oral dosing: the milk [14C] peaked between 2 and 3 h posttreatment and remained steady thereafter. The milk to blood (M/B) [14C] concentration ratios were markedly greater during 0.5 to 1 h in the ivg group than in their po dosed counterparts

  3. Preparation of 14C-catechins by tea cell culture

    The preparation of 14C labelled catechins was studied by feeding 14C labelled precursor to tea cultured cells. Two labelled precursors were tested and their effects were compared. The dynamics of absorption and transformation of fed precursors were analyzed and the effects of pre-culture as well as UV light pretreatment on product labelling rate were evaluated. Product analysis was also made by HSCCC and HPLC techniques

  4. Radiochemical synthesis of 14C-labelled pesticides

    Radioisotopic derivatives of pesticides labelled with either 14C or tritium are indispensable experimental tools for toxicology or metabolism studies required for registration of new compounds. The radiochemical synthetic pathways leading to the preparation of 14C-labelled pesticides of high specific activity, good chemical/radiochemical yield, and high radiochemical purity are presented for three groups of pesticides; triazines, aryl-haloids, and organometallic compounds. (N.T.). 10 refs., 1 tab

  5. 14C-Metampicillin stability in several physiological sera

    Degradation of 14C-metampicillin incorporated to several physiological sera for medical uses has been studied. Influence of environmental conditions as well as possible interaction with the solvent have been specially analyzed. Degradation level of the labelled multiplication has been determined and its degradation products have been separated by using chromatographic and radiochemical methods. Likewise, the 14C-metam picill synthesis has been described. Finally, the results obtained have been discussed and evaluated. (Author) 9 refs

  6. Study on the dynamics in absorption of 32P by hybrid wheat at elongate stage

    The dynamics of absorbing 32P of hybrid wheat at elongate stage is studied under pot culture conditions. The results show that the absorption capacity of hybrid wheat to 32P is in agreement with regression equation. The increased extent of absorption for them is greater than that for parent with time, and the reduction rate of absorption is lower than the parent significantly. Their root activity is much higher than that of the parent, too. The overall heterotic vigor of hybrid wheat on the absorption capacity to 32P is the sum of that of all organs

  7. A modified method for synthesis of [γ-32P] labelled adenosine triphosphate

    Production of [γ-32P]-ATP using three glycolysis enzymatic reaction i.e. glyceraldehyde 3-phosphate dehydrogenase, 3-phosphoglyceric phosphokinase and lactate dehydrogenase has been conducted. dl-glyceraldehyde 3-phosphate, Adenosine Diphosphate and H332PO4 was used as precursors for this reaction. Purification of [γ-32P]-ATP was performed by using DEAE-Sephadex column chromatography. The result suggested that this simple method could be used for producing [γ-32P]-ATP to support the provision of radiolabeled nucleotide for biotechnology research in Indonesia. (author)

  8. Synthesis of [14C]-labelled dihydropyridine calcium channel entry blockers: nicardipine-[4[14C] and RS-93522-[4-14C

    The Hantzsch synthesis has been applied to the general preparation of 4-aryl-dihydropyridines labelled in the metabolically stable 4-position of the dihydropyridine ring. The synthesis is based on the preparation of a key common intermediate, m-nitrobenzaldehyde-[formyl-14C], in high yield from Ba14CO3. (author)

  9. {sup 14}C in human diet in three Spanish locations; {sup 14}C en dieta humana en tres localizaciones espanolas

    Gomez Martinez, I.; Santos Arevalo, F. J.; Manjon, G.; Garcia-Tenorio, R.

    2011-07-01

    {sup 14}C reach humans via the diet. In this study we present the results of diet samples from three locations type Spanish, Seville, Caceres and Tenerife. These diets are collected quarterly and historical dates back to early 2008.

  10. Metabolic Fate of [(14)C]Diuron and [(14)C]Linuron in Wheat (Triticum aestivum) and Radish (Raphanus sativus).

    Pascal-Lorber, Sophie; Alsayeda, Haifaa; Jouanin, Isabelle; Debrauwer, Laurent; Canlet, Cécile; Laurent, François

    2010-01-01

    Metabolism of xenobiotics in plants usually occurs in three phases, phase I (primary metabolism), phase II (conjugation processes), and phase III (storage). The uptake and metabolism of [(14)C]diuron and [(14)C]linuron were investigated in wheat and radish. Seeds were sown in quartz sand and irrigated with a nutrient solution of either radioactive herbicide. Plants were harvested after two weeks, and metabolites were extracted and then analyzed by radio-reverse-high-performance liquid chromat...

  11. Determination of phagocytosis of /sup 32/P-labeled Staphylococcus aureus by bovine polymorphonuclear leukocytes

    Dulin, A.M.; Paape, M.J.; Weinland, B.T.

    1984-04-01

    A procedure for the measurement of phagocytosis by bovine polymorphonuclear leukocytes (PMN) of /sup 32/P-labeled Staphylococcus aureus was modified so that a larger number of samples could be compared in a single run, and smaller volumes of sample, PMN, and /sup 32/P-labeled S aureus could be used. Results were highly reproducible, with a coefficient of variation between duplicate determinations of less than or equal to 2%. Lysostaphin was prepared from the supernatant of S staphylolyticus and was compared with a commercially available preparation. Effects of lysostaphin on PMN and influence of incubation media on release of /sup 32/P from /sup 32/P-labeled S aureus by lysostaphin were examined.

  12. Uptake and distribution of 32P in the budded and self-rooted grape varieties

    In the self-rooted and budded varieties of grape (Vitis vinifera L.), the total P and 32P contents were high in 'Anabee-Shahi', but low in in 'Muscat'. The growing shoots contained more P than old stems and roots in all the varieties. In the budded plants, 'Kali Sahebi' scion budded on 'Anab-e-Shani showed the maximum 32P and total P in the shoots, but 'Muscat' scion budded on 'Anab-e-Shahi' accumulated more P in the roots and very low 32P in the growing shoots. Auto-radiographs of shoots also showed that 'Kali Sahebi' budded on 'Anab-e-Shani' rootstock accumulated more 32P in the shoots. (author)

  13. Root activity studies of cashew plants (Anacardium Occidentale L.) using 32P radioisotope

    In this preliminary study, we are looking at levels 32P and depths of soil injections on uptake by plants using the injection techniques in root activity studies. 32P activities can be detected in the leaves and flower parts of plants two weeks after injection in the soil. Reasonable count rate can be obtained by using lower level of 32P (1.6 mCi/tree) than recommended (5 mCi/tree). 32P counts were higher in younger than older leaves. Flowers had the least count. Differences in injection depths (5 and 15 cm) could not be detected. Differences in count rate were detected due to position of leaves and flowers (upper and lower canopy) in some of the sampling intervals. (author)

  14. Optimization time synthesis of nucleotide labelled [γ-32P]-ATP

    Adenosine triphosphate-labelled with γ-32P([γ-32p]-ATP) has been widely used in the biotechnology research, usually as a tracer to study aspects of physiological and pathological processes. In order to support biotechnology research in Indonesia, a process for production of [γ-32P]-ATP with enzymatic reaction was used as precursors DL-glyceraldehydde 3-phosphate, Adenosine Diphosphate (ADP) and H332PO4, and enzyme glyceraldehid 3-phosphate dehydrogenase, 3-phosphoglyceryc phosphokinase and lactate dehydrogenase. Optimization of incubation time labeled nucleotide synthesis process is performed to find the optimum conditions, in terms of the most advantageous time in the synthesis process. With the success of the synthesis and optimization is done incubation time of synthesis labeled nucleotide, the result suggested can be used for producing [γ-32P] -ATP to support the provision of radiolabeled nucleotide for biotechnology research in Indonesia. (author)

  15. Reactor production and separation of no-carrier added 32P for medical applications

    Phosphorous-32 is an attractive and widely used therapeutic radionuclide owing to its favorable nuclear characteristics. The major application of 32P is the treatment option for a distinct subgroup of elderly patients with polycythemia vera and leukemia. The tremendous prospects associated with the use of 32P along with the challenge of providing 32P of acceptable specific activity and purity amenable for in vivo therapy, led to development of a 32P production strategy. The 32S(n,p)32P route of production provide the scope of obtaining high specific activities or no carrier added (NCA) 32P. In a typical batch of 14 nos. of neutron irradiated Al containers, each containing 18 g of sulphur, were processed. In the quest for an effective separation method to isolate micro gram of 32P formed during the neutron irradiation of sulphur, the prospect of using distillation under reduced pressure to achieve complete removal of sulfur seemed to be an effective proposition and motivated us to adopt. The experimental parameters that influence the distillation were identified and a careful control has been exercised to ensure complete removal of sulphur from 32P within reasonable time period. The 32P remained in the distillation flask was quantitatively collected by leaching with 0.05 N HCl with gentle heating at 80℃ for 3 hours. In the light of the perceived need to remove cationic impurities from the 32P leachate, it was passed through an ion-exchange chromatography column containing a cation exchange resin (Dowex 50 x 8 H+, 100-200 mesh) wherein all the cationic impurities get trapped and H332PO4 solution was collected as effluent. Recognizing the fact that H332PO4 produced is to be used for clinical applications, a thorough quality assessment was carried out. Radionuclidic purity was ascertained by a measurement of its half-life. In order to establish the absence of extraneous gamma emitting radionuclide impurities, gamma spectrum of the appropriately diluted samples of 32P

  16. Characterization of 14C in Swedish light water reactors.

    Magnusson, Asa; Aronsson, Per-Olof; Lundgren, Klas; Stenström, Kristina

    2008-08-01

    This paper presents the results of a 4-y investigation of 14C in different waste streams of both boiling water reactors (BWRs) and pressurized water reactors (PWRs). Due to the potential impact of 14C on human health, minimizing waste and releases from the nuclear power industry is of considerable interest. The experimental data and conclusions may be implemented to select appropriate waste management strategies and practices at reactor units and disposal facilities. Organic and inorganic 14C in spent ion exchange resins, process water systems, ejector off-gas and replaced steam generator tubes were analyzed using a recently developed extraction method. Separate analysis of the chemical species is of importance in order to model and predict the fate of 14C within process systems as well as in dose calculations for disposal facilities. By combining the results of this investigation with newly calculated production rates, mass balance assessments were made of the 14C originating from production in the coolant. Of the 14C formed in the coolant of BWRs, 0.6-0.8% was found to be accumulated in the ion exchange resins (core-specific production rate in the coolant of a 2,500 MWth BWR calculated to be 580 GBq GW(e)(-1) y(-1)). The corresponding value for PWRs was 6-10% (production rate in a 2,775 MWth PWR calculated to be 350 GBq GW(e)(-1) y(-1)). The 14C released with liquid discharges was found to be insignificant, constituting less than 0.5% of the production in the coolant. The stack releases, routinely measured at the power plants, were found to correspond to 60-155% of the calculated coolant production, with large variations between the BWR units. PMID:18617793

  17. Radioactive 32P incorporation in liver of mice fed with Aspergillus terreus contaminated feed

    The distribution of 32P during toxicosis due to Aspergillus terreus, a common food contaminant, reported to procedure the toxin terreic acid, in addition to few others, was studied in mice. Radioactive 32P was injected intraperitoneally to the control mice and the experimental ones, which were fed with Aspergillus terreus contaminated feed, as well as the toxin terreic acid. After 24 hrs, both control and experimental animals were sacrificed. 32P incorporation in various fractions of liver were studied. 0.5 cm3 of each fractions was spread on a planchette and dried at 60 deg C. 32P activity was measured using a thin end window Geiger Mueller tube connected to Panax-type 100 C counter. No corrections were necessary for self absorption. In mice, fed with the contaminated feed, more 32P got incorporated in the nucleic acid fraction than seen in protein, barium soluble and barium insoluble fractions, whereas 32P incorporation in lipid fraction was lower. (T.G.)

  18. 32P-labeled hydroxyapatite particles for use in radiation synovectomy

    Radionuclides decaying by emission of β- particles of varying energies have been proposed for treating arthritis of various joints. Hydroxyapatite (HA) (Ca10(PO4)6(OH)2) is a preferred substrate for developing radiochemical agents for management of arthritis. Reactor produced 32P was evaluated for its suitability for preparation of a potent radiolabeled agent for the treatment of arthritis based on HA particles. 32P is produced by both (n,γ) and (n,p) routes from red phosphorus and elemental sulfur respectively. The preparation of 32P labeled HA particles (particle size 2-10 μm) was carried out using 10 mg HA at pH 7-8. The maximum achievable specific activity of 222 MBq 32P/mg of P in Dhruva research reactor employing radiative neutron capture reactions on red P has limitations in its utility in HA formulation, however, using no carrier added (NCA) 32P, HA could be labeled in high radiochemical purity (>95%). The radiolabeled particulates showed excellent in vitro stability at room temperature. Intra-articular injection of 32P-HA particles in the knee joint showed complete retention of activity within the synovial cavity with no measurable activity leaching out from the joint till 14 d post injection, in case of Wistar rats bearing arthritis. (author)

  19. Internal radiotherapy using 32P colloid or microsphere for refractory solid tumors

    The aim of this work was to study the effectiveness of 32P colloids or microspheres, by arterial interventional administration or stromal injection in the treatment of refractory solid tumors. By arterial intervention, under the guidance of computerized tomography, X-ray, ultrasonogram, or under direct vision of the surgical field, 32P microspheres (259-685 MBq) or radioactive colloid (281-666 MBq) was administered to 60 cases with refractory solid tumors. Tumor inhibition rate, side effects, survival period, and so on were observed. The tumor growth was obviously inhibited after the intratumoral injection of 32P colloid. The average survival time in the 60 cases was 35 months with a high tumor inhibition rate (93.4%). Thirty-one cases were completely relieved (51.7%), and 25 cases achieved partial remission (PR, 41.7%). One case with right lobe hepatocellular carcinoma has survived 90 months. The drug was ineffective only in four cases, including one patient who died of gastrointestinal hemorrhage and three of hepatic failure. No other obvious side effects were observed. Intratumoral necrosis, intense fibrosis in the tumor mass, and an integrated capsule encompassing the tumor were revealed by histological examination. Arterial interventional administration or stromal injection with 32P microspheres or colloid revealed a very fair clinical effectiveness in the treatment of refractory solid tumors. The range of safe effective dosage for 32P glass microspheres and 32P chromic phosphate in one treatment course is 555-740 MBq and 185-370 MBq, respectively. (author)

  20. Measuring the 14C content in liquid scintillators

    Enqvist, T.; Barabanov, I. R.; Bezrukov, L. B.; Gangapshev, A. M.; Gavrilyuk, Y. M.; Grishina, V. Yu; Gurentsov, V. I.; Hissa, J.; Joutsenvaara, J.; Kazalov, V. V.; Krokhaleva, S.; Kutuniva, J.; Kuusiniemi, P.; Kuzminov, V. V.; Kurlovich, A. S.; Loo, K.; Lubsandorzhiev, B. K.; Lubsandorzhiev, S.; Morgalyuk, V. P.; Novikova, G. Y.; Pshukov, A. M.; Sinev, V. V.; Słupecki, M.; Trzaska, W. H.; Umerov, Sh I.; Veresnikova, A. V.; Virkajärvi, A.; Yanovich, Y. A.; Zavarzina, V. P.

    2016-05-01

    We are going to perform a series of measurements where the 14C/12 C ratio will be measured from several liquid scintillator samples with a dedicated setup. The setup is designed with the aim of measuring ratios smaller than 10-18. Measurements take place in two underground laboratories: in the Baksan Neutrino Observatory, Russia and in the Pyhäsalmi mine, Finland. In Baksan the measurements started in 2015 and in Pyhäsalmi they start in the beginning of 2015. In order to fully understand the operation of the setup and its background contributions a development of simulation packages has also been started. Low-energy neutrino detection with a liquid scintillator requires that the intrinsic 14C content in the liquid is extremely low. In the Borexino CTF detector at Gran Sasso, Italy the 14C/12C ratio of 2 × 10-18 has been achieved being the lowest 14C concentration ever measured. In principle, the older the oil or gas source that the liquid scintillator is derived of and the deeper it situates, the smaller the 14C/12C ratio is supposed to be. This, however, is not generally the case, and the ratio is probably determined by the U and Th content of the local environment.

  1. In vitro synthesis and purification of UDP-[14C] galacturonate

    Pectins comprise a major component of the cell wall and much research has focused on degradation of pectins during ripening and senescence. However, little research has been conducted on pectin synthesis, partly due to a lack of commercial availability of UDP-[14C]galacturonic acid for use as a substrate in assaying galacturonan synthase. We report on the modification and integration of several procedures to synthesize UDP-[14C] galacturonic acid from commercially available UDP-[14C]glucuronic acid. A microsomal pellet containing UDP-D-glucuronate-4-epimerase was extracted from 5-day-old mung bean hypocotyls (Phaseolus aureus) and radish roots (Raphanus sativus L.) by ultracentrifugation at 30,000 rpm for 50 min. The UDP-[14C]galacturonic acid produced was separated from remaining UDP-[14C]glucuronic acid and other products by electrophoresis in pyridine:acetate:H2O on silica gel. Spots were detected by autoradiography, eluted with 80% ethanol, and purified using anion exchange chromatography

  2. Algal photosynthetic activity measurement by 14C uptake, (1)

    There are many sample preparation techniques for 14C-labeled phytoplankton for radioactivity measurement by liquid scintillation counting. A number of sample preparation procedures were tested to identify the ones most suitable for the intended experiments. The following results were obtained: 1. The calculated radioactivity of solubilized samples were about 10% lower than that of combusted samples. This was caused by settling out of algal cells. 2. The agreement between calculated radioactivity of solubilized samples and combusted samples was improved by the addition of Cab-O-Sil. 3. Virtually all of the residual inorganic 14C radioactivity was removed during drying. 4. The loss of 14C radioactivity caused by formaldehyde fixation differed from species to species. Based on these results, the following procedure was selected for use in our experiments: 1. After incubation with 14C, the 14C-labeled phytoplankton samples were immediately filtered and rinsed with filtered seawater under low illumination. 2. The filters were then dried in a vacuum desiccator with sodalime and silica gel. 3. The dried filters were solubilized with ethylene glycol monomethyl ether-toluene fluor which contains PPO, POPOP, and Cab-O-Sil. 4. The activity of solubilized samples was measured using liquid scintillation counting. (author)

  3. Whole-body autoradiographic study on the distribution of pivampicillin-14C labeled at the ampicillin and ester moieties in mice, as compared with those of ampicillin-14C, formaldehyde-14C and pivalic acid-14C

    The distribution of pivampicillin-14C labeled at the phenylglycyl and the oxymethylene moieties and ampicillin-14C were investigated by whole-body autoradiography after oral administration to mice. The distribution of formaldehyde-14C and pivalic acid-14C was also investigated for comparison. The results revealed that, i) pivampicillin is absorbed from intestine much more rapidly and to a larger extent than ampicillin, ii) the distribution pattern was, however, the same for the two drugs, being mainly restricted to the excretory organs such as the liver, kidney, gall and urinary bladders and intestinal tract, and iii) the oxymethylene moiety, the ester group, showed a completely different distribution pattern, being distributed in the bone marrow, pancreas, intestinal mucosa, spleen and thymus; the pattern being the same as that after administration of formaldehyde-14C. It was therefore suggested that pivampicillin is hydrolyzed in vivo to form ampicillin and formaldehyde before entering into the general circulation and that formaldehyde formed is partly incorporated into the general metabolic pathways in the tissues of a rapid cell division or protein synthesis. Pivalic acid, which is to be liverated simultaneously, was shown to be well absorbed, distributed in the bone, kidney, olfactory bulb, salivary gland and some adipose tissues and finally excreted into the urine mostly as its conjugated forms. (author)

  4. Temporal distribution of bomb 14C in a forest soil

    Patterns of 14C enrichment in the superficial plant debris and mineral soil horizons of an established woodland have been monitored at regular intervals during the past 15 years. These data are compared with a model evaluation of carbon turnover based on the recorded changes in atmospheric 14C concentration since AD 1900. Leaf litter and decomposing plant debris are characterized by steady-state turnover values of ca 2 and ca 8 years, respectively. A two-component system of fast (≤20 yr) and slow (ca 350 yr) cycling carbon is indicated for the surface (0-5cm) soil humus; below 10cm, the fast component is rare (14C to the soil carbon pool

  5. Persistence of 14C maneb in lettuce plants an soil

    Maneb residue is studied on lettuce plant and soil after spraying on greenhouse with 14C maneb. The residues declined with time. After 37 days from the application, 14C maneb residues in water extracts declined to 1,5. 10-2ug/g from 5,8. 10-1ug/g of the zero day sample in lettuce plants and 4,6. 10-3ug/g from 1,73. 10-1ug/g in soil. The 14C internals residues in lettuce and soil increase respectively till 16 days and 24 days, then decrease to 88% and 4,05% after 37 days. ETU was present in lettuce plant after 8 days then decreases with time. Two metabolites were identified by TLC (EU,ETU)

  6. Synthesis of paclitaxel-C3`-{sup 14}C

    Walker, D.G.; Standridge, R.T.; Swigor, J.E. [Bristol-Myers-Squibb Co., Syracuse, NY (United States). Pharmaceutical Research Inst.

    1995-12-31

    Reductive cleavage of the C13 side chain of paclitaxel (3) followed by regioselective silylation gave 7-triethylsilybaccatin lll (6). Successive reaction of L-threonine methyl ester hydrochloride (7) with tertbutoxydiphenylchlorosilane, benzaldehyde-C7-{sup 14}C and acetoxyacetyl chloride/triethylamine gave a 92:8 ratio (NMR) of azetidinones in 57% yield from 7. Removal of the chiral auxiliary, and 3-O-triethylsilylation and N-benzoylation provided (3R,4S)-cis-1-benzoyl-3-O-(triethylsilyl)-4-phenylazetidin-2-one-C 4-{sup 14}C (18). Coupling of 18 and 6 followed by deprotection gave 1.12 g of paclitaxel-C3`-{sup 14}C having a specific activity of 16.4 mCi/mmol and a radiochemical purity of 96%. (Author).

  7. Transformation of Straw 14C in Ultisol and Vertisol

    WANGZHIMING; HUANGDONGMAI; 等

    1998-01-01

    Laboratory incubation was conducted to investigate transformation of straw 14C in Ultisol and Vertisol under aerobic conditiol for 112 d at 30℃,Dried and ground 14C-labeled rice and majze straws sere mixed with the soils at the rate of 2.5g kg-1 ,Decomposition of the straw C and native soil C both revealed two stages,being faster during the intial day,and slower thereafter,About 37.33%-48.80% of the straw C and 4.22%-6.83% of the native soil C decomposed by the end of the incubation.The kinds of the straws only slightly influenced the rates of their decomposition in soils,however,some retardation was found in Ultisol at the intial decomposition stage due to its lowr pH.Positvie priming effects were observed in the soils spplied with straw ,and the rate of priming effect ranged from 7.23% to 13.80%.Net losses of native soil C were found under such incubation conditions ,except Ultisol with rice straw.Soil biomass of and 14C decreased gradually with incubation time,and seemed to be consistent with the decomposition patterns of straw C and native soil C.The ratio of biomass 12C to biomass 14C ranged from 1.35 to 3.37 .soil biomass C occupied 1.17%-2.32% of the total soil organic C,and the proportion of biomass 14C to the residual 14C varied from 7.3% to 14.3%.

  8. A new 14C AMS facility at IUAC, New Delhi

    A new state of art Accelerator Mass Spectrometry (AMS) facility for 14C has been developed at IUAC. This facility is based on the 0.5 MV Pelletron accelerator and an Automated Graphitization Equipment (AGE). In addition to the 14C measurements, this system has the capability to perform 10Be and 26AI measurements also. The system is called XCAMS i.e., Compact, Accelerator Mass Spectrometer eXtended for 10Be and 26AI. A detailed description of the newly developed AMS facility and the recent measurements will be discussed

  9. Verification of the dispersion model by airborne carbon 14C

    This paper provides insight in the verification of the Lagrangean dispersion model for dose calculation in the environment. The verification method was based on the measurement of the airborne carbon 14C concentration which can be slightly increased close to the nuclear power plant. The results proved that this method is sensitive enough and that the sensitivity analysis can be used for model verification or for identification of possible improvements of the used meteorological data. The Lagrangean model is used at Krsko nuclear power plant (NPP) for calculation of dispersion coefficients and dose in the environment. To show compliance with the authorized dose limits it is required to present a realistic calculation of the dose to the public. This is a numerical model designed to calculate air pollution dispersion in the area of 25km x 25km. The model uses on-line local meteorological measurements. The same model was already verified for another location around a coal- fired power plant based on emission and environmental measurements of SO2. Krsko NPP is placed near the Sava River in a semiopened basin surrounded by several hills. The region is characterized by low winds and frequent thermal inversions. This paper presents a verification of the short range dispersion model based on the fact that the airborne carbon 14C concentration can be slightly increased close to the nuclear power plant. Other radioactive effluents are not detectable in the environment and carbon 14C measurements are accurate enough to detect small deviations from natural 14C levels and to compare them with the calculated concentration based on 14C effluents. The most of airborne 14C is released during the refuelling outage. Within the pre-selected period of ten days, increased effluents of 14C in the form of CO2 were sampled from the plant ventilation. The average atmospheric dispersion parameters were calculated for two locations in the environment where CO2 sampling plates were installed

  10. AMS of {sup 14}C at low energies

    Suter, M.; Huber, R.; Jacob, S. [ETHZ, Zurich (Switzerland); Synal, H.A. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-09-01

    At the ETH/PSI AMS facility {sup 14}C test measurements have been performed at low terminal voltages of 0.5 and 1 MV in order to study the feasibility of AMS with very small accelerators. These experiments have demonstrated that interfering molecules ({sup 13}CH and {sup 12}CH{sub 2}) in charge states 1{sup +} and 2{sup +} can be destroyed in an adequate Ar gas stripper. These new results imply the feasibility of a new generation of very small accelerator systems for {sup 14}C. (author) 1 fig., 3 refs.

  11. Biliary excretion of intravenous [14C] omeprazole in humans

    We have studied the biliary excretion of [14C] omeprazole in humans. The study was performed in eight healthy subjects and the technique used was based on multiple marker dilution principles with double-lumen tubes placed in both the stomach and intestine. The results obtained show a 16% biliary excretion of [14C] omeprazole. These data suggest a minimal spillover of omeprazole from the gastric mucosa into the gastric lumen in humans. The results also agree with previous data of the fecal recovery of radiolabeled omeprazole that suggest that the fecal excretion of intravenous omeprazole in humans is entirely accounted for by biliary excretion

  12. Bioaccumulation factor for 32P measured in bluegill, Lepomis macrochirus, and catfish, Ictalurus punctatus

    The ratio of the bioaccumulation factors for 32P and phosphorus was determined for edible tissue in two species of freshwater fish by measuring the specific activity (32P activity per milligram phosphorus) in muscle relative to feed. The 32P tracer was added to the feed at a uniform level throughout the study. Feeding was at two levels: ad libitum and at a lower but constant intake per body weight. In the main experiment, bluegill were maintained in a large flow-through tank and sacrificed at approximately weekly intervals for 51 d of 32P accumulation and 28 d of depuration to compare the specific activity with values predicted with a calculational model. In experiments performed in smaller aquaria, the specific activity in bluegill and catfish muscle was compared at two feeding levels and two temperatures. In addition, unfed fish were exposed to 32P in water at a known specific activity to determine the extent of phosphorus uptake directly from water. The pattern of specific activity increase and decrease in fish muscle during the accumulation/depuration experiment was consistent with a one-compartment model, so that specific activity ratios at steady state could be predicted from measurements during relatively brief exposures. On this basis, the ratio of the bioaccumulation factors of 32P and phosphorus in fish feeding ad libitum was 0.081 for bluegill and 0.17 for catfish. Hence, at a mean phosphorus bioaccumulation factor of 70,000, the factors for 32P are 6000 and 12,000, respectively. The ratios were less at lower phosphorus intakes associated with lower feeding rates; moreover, the lesser value for bluegill occurred at a much lower phosphorus intake than by catfish

  13. Fractionation of phosphorus added as a vegetal residue (32 P) and a fertilizer (32 P) between soil, plant and microbial biomass

    Sugar cane straw and/or P-fertilizer phosphorus-32 labelled were added to a Red Yellow podzolic soil from Goiana-PE. The treated samples were used in a pot experiment, growing sorghum plants for 4 and 6 weeks, and in an incubation experiment with incubation periods of 1, 2, 3, 4 and 6 weeks without plants in order to follow the dynamics of the P added. After each harvest and incubation period the soil were analysed for 31 P and 32 P in the microbial biomass and in sequential extracts with resin (Pi), 0.5 M Na H Co3 (Pi, Po) and 0.1 N NaOH (Pi, Po). The 31 P and 32 P contents of the sorghum in the pot experiment were also determined. (author)

  14. Methods for treating and conditioning of 14C containing health care waste

    Health care radioactive waste was previously accepted at Necsa and disposed of on this site in near-surface trenches. This practice was terminated by the regulator during 1997 and since then waste drums have been stored and have now become a Necsa liability. These waste drums containing unknown quantities of 14C. About 2500 drums have been accumulated over the years at the Necsa site. The 14C and 3H contents could not be determined with non-destructive assay methods. A study to minimize the further accumulation of 14C containing health care waste was undertaken and some new regulations implemented to prevent further increase of the liability.The bio-hazardous nature of the waste proved to be the main complication in the development of appropriate characterization and conditioning methods. Possible methods to sterilize the waste as a first step were consequently investigated, and this regards two interesting options received attention. The first was the so-called Stericycle ETD process, during which the waste is shredded in an enclosed environment and then sterilized by means of a technique known as Electro Thermal De-activation, and the second was sterilization with Gamma rays. The latter method had the advantage that shredding and repacking were not required.Once the waste was sterilized the waste could be characterized. The most practical method to do this was to compact the drum in a supercompactor and to analyze the liquid released from the drum during compaction in a laboratory.Reasonably accurate estimates of the 14C contents of the waste packages were obtained in this way and at the same time the waste volume to be disposed of was reduced by at least a factor of four. The option to dispose of the waste without doing any quantification of the 14C was also investigated. This option does not require the waste drums to be opened and therefore no sterilization is required. Characterization is in this case limited to assaying the drums for nuclides that can be

  15. Insulin and thyroxine effect on 32P incorporation in the phospholipids of chicken intestinal mucosa

    Trials were conducted with 56-day-old broiler chickens. The effect was followed up of insulin and alloxan as well as of L-thyroxine and 6-methylthiouracil on 32P incorporation in phospholipids of the duodenal mucosa. A segment of the duodenum was isolated and Na2H32PO4 was introduced therein. The lipids were extracted from duodenal mucosa and the individual phospholipids were separated by means of thin layer chromatography on sillica gel-G. Radioactivity was determined of individual phospholipid fractions. Blood glucose level was studied in insulin and alloxan-treated chickens. The inference was drawn that insulin significantly enhances 32P incorporation in the phospholipids in broiler chicken duodenal mucosa. The drop in blood glucose in insulin-treated chickens is inversely proportional to 32 P inclusion in individual phospholipids of duodenal mucosa. L-thyroxine exerts positive effect in chickens concerning 32P incorporation in lecithin and lysolecithin, this effect being negative with respect to sphingomyelin, cephalin and cardiolipin. Thyroid gland inhibition by 6-methylthiouracil induces negligible decline in 32P inclusion. (author)

  16. Preparation and evaluation of various 32P sources for intravascular brachytherapy

    A relatively high per cent of restenoses, being a long-term complication of percutaneous transluminal coronary angioplasty (PTCA), can be significantly reduced by short-range ionizing radiation applied locally, immediately after PTCA. In search for dosimetrically favourable and easy to handle radiation sources for this purpose, we tried a pure β- emitter 32P (t1/2=14.3 days). Ways of preparation of 32 P sources were the following: (1) Neutron activation of 31P layers implanted into metallic surfaces by ionic methods; (2) Conversion coating of metallic surfaces in aqueous solutions containing 32PO43- ions; (3) Direct application of Na2H32 PO4 solutions in the angioplasty balloon. It was shown that: (1) 32 P sources obtained by 31 P ion implantation followed by neutron activation can be useful, but only if activation of the support material by thermal neutrons is negligible; (2) Phosphate layers on stainless steel surface exhibit rather poor adhesion. Similar layers on titanium require further studies; (3) Liquid 32 P sources ensure very good radial dose distribution but only utmost care in filling the balloon can give a reliable activity-dose dependence. Dosimetry of liquid sources, performed in a PMMA phantom by thermoluminescence method showed that 32 P sources of radioactive concentration of 200 MBq/cm3 can deposit therapeutic dose during about 12 min of exposition. TL detectors manufactured for this purpose in our laboratory show very good spatial resolution and can be recommended for similar studies. (author)

  17. Changes of decay rates of radioactive 111In and 32P induced by mechanic motion

    2007-01-01

    The changes of decay rates of radionuclide 111In(electron capture) and 32P(β decay) induced by exter-nal mechanic motion are studied. The results indicate that,in the external circular rotation in clockwise and anticlockwise centrifuge on Northern Hemisphere(radius 8 cm,2000 r/min) ,the half life of 111In compared with the referred(2.83 d) is decreased at 2.83% and increased at 1.77%,respectively;the half life of 32P compared with the referred(14.29 d) is decreased at 3.78% and increased at 1.75%,respec-tively. When the clockwise and anticlockwise rotations increase to 4000 r/min,the half life of 111In is decreased at 11.31% and increased at 6.36%,respectively;the half life of 32P is decreased at 10.08% and increased at 4.34%,respectively. When the circular rotation is removed,the decay rates of 111In and 32P return back to the referred,respectively. It is found that the external circular rotations in clockwise and anticlockwise centrifuge selectively increased and decreased the decay rates of 111In and 32P,respec-tively,and the effects are strongly dependent on the strength of circular rotation. It is suggested that these effects may be caused by the chiral interaction.

  18. Synthesis of [sup 14]C-radiolabeled ractopamine hydrochloride

    Terando, N.H. (DowElanco, Greenfield Labs., Greenfield, IN (United States))

    1992-09-01

    Ractopamine HC1 was uniformly labeled with carbon-14 in one of two phenyl rings as a requirement for animal metabolism studies. The six-step synthesis was completed in a 14% yield. Product instability on silica gel complicated purification, but development of a chromatographic method afforded ractopamine HCl-[sup 14]C with a radiochemical purity of 98.2%. (author).

  19. Synthesis of 14C-radiolabeled ractopamine hydrochloride

    Ractopamine HC1 was uniformly labeled with carbon-14 in one of two phenyl rings as a requirement for animal metabolism studies. The six-step synthesis was completed in a 14% yield. Product instability on silica gel complicated purification, but development of a chromatographic method afforded ractopamine HCl-14C with a radiochemical purity of 98.2%. (author)

  20. Photosynthetic incorporation of 14C by Stevia rebaudiana

    The photosynthetic incorporation of 14 by Stevia rebaudiana specimens was investigated. The 14C incorporation, when the isotope was furnished to the plant in form of 14CO2, was rapid. After 24 hours, the radioactivity has been incorporated into a great number of compounds including pigments, terpenes, glucose, cellulose and also stevioside and its derivatives. (M.A.C.)

  1. Biomonitoring of 14C in the vicinity of NPPs

    Světlík, Ivo; Molnár, M.; Svingor, E.; Rinyu, L.; Futó, I.; Michálek, V.

    Brasov : IRPA, 2007, s. 1-10. [IRPA Regional Congress for Central and Eastern Europe. Brasov (RO), 24.09.2007-28.09.2007] Institutional research plan: CEZ:AV0Z10480505 Keywords : 14C excess * Suess effect * biota monitoring * nuclear power plants Subject RIV: DG - Athmosphere Sciences, Meteorology

  2. Biokinetic studies on 14C-chitosan in rats

    The absorption and the basic metabolism of chitosan in rats are investigated. The results indicated that 14C-chitosan from gastrointestinal tract was absorbed, metabolized and excreted quickly without re-bioavailability. The radioactive compounds perhaps with specifically chemical forms in serum, liver and the contents of small intestines were separated on GPC column and measured by radioactivity counting. A big pile of peaks with the retention volume almost same as that of standard 14C-chitosan and another sharp one with the retention volume in the range of higher molecular weight same as that of BSA were discovered in analysis respectively for contents of intestine and serum or liver. The sharp peak would disappear if the proteins contained in the serum or liver were removed. In addition, and interesting tail peak, followed with the pile ones and eluted with the retention volume of lower molecular weight range same as that of chitooligosaccharides was also found in each of the 3 samples, ignoring the protein removal or not. These results suggested that most of 14C-chitosan was not to be digested in intestine. On the other hand, a small amount of 14C-chitosan was likely to be absorbed directly or after degraded to small molecular compounds into blood, liver and other tissues, and then connected with the proteins. Perhaps it is these trace materials that were playing important roles in reduction of the bioavailability of radiostrontium in rats

  3. The synthesis of [14C] C I pigment violet 19

    For the custom synthesis of radiolabeled compounds in the authors laboratory, aside from spectroscopic examination, their identity and radiochemical purity is routinely corroborated by demonstration of cochromatography with an authentic cold standard. In the synthesis of [14C] red pigment 1 for the Cosmetic Toiletry and Fragrance Association, its insolubility precluded this. The preparation as well as characterization of 1 is described

  4. Fungal bio-degradation of 14C-parathion

    14'C-parathion (670 Bq) was applied to mineral salt medium (MSM) to examine and evaluate its biodegradation by some fungi. The studied isolates were Alternaria alternate, Fusarium oxysporim and trichoderma viride. The inoculated media were incubated at 30 oC for periods of 2, 4, 6 and 8 days. Ta each interval, mycelia were separated from nutrient solution and extracted for its radioactivity. However, non extractable compounds were liberated by combustion. Quantitative and qualitative analysis were carried out for the radioactive compound in mycelia l extracts and residues as well as the fungal culture filtrate. Balance sheet for total recovered radioactive compounds was concluded 14'C-parathion metabolism was expressed as original compound, polar metabolite, non polar metabolites and non extractable residues and then degradation rate was calculated. araesults indicated that there was continuous penetration for the radioactivity into mycelia tissues and the maximum, accumulation was recorded by Fusarium Oxysporium. The fungi under investigation showed considerable variations regarding their capacity to degrade the radioactive pesticide. Trichoderma viride exhibited the maximum capability to catabolism the the 14C-parathion as it exerted the maximum degradation rate. Fusarium and Alternate alter nata showed less degradation rates for the 14C- pesticide under investigation. (Author)

  5. Extraction of in situ cosmogenic 14C from olivine

    Pigati, J.S.; Lifton, N.A.; Timothy, Jull A.J.; Quade, Jay

    2010-01-01

    Chemical pretreatment and extraction techniques have been developed previously to extract in situ cosmogenic radiocarbon (in situ 14C) from quartz and carbonate. These minerals can be found in most environments on Earth, but are usually absent from mafic terrains. To fill this gap, we conducted numerous experiments aimed at extracting in situ 14C from olivine ((Fe,Mg)2SiO4). We were able to extract a stable and reproducible in situ 14C component from olivine using stepped heating and a lithium metaborate (LiBO2) flux, following treatment with dilute HNO3 over a variety of experimental conditions. However, measured concentrations for samples from the Tabernacle Hill basalt flow (17.3 ?? 0.3 ka4) in central Utah and the McCarty's basalt flow (3.0 ?? 0.2 ka) in western New Mexico were significantly lower than expected based on exposure of olivine in our samples to cosmic rays at each site. The source of the discrepancy is not clear. We speculate that in situ 14C atoms may not have been released from Mg-rich crystal lattices (the olivine composition at both sites was ~Fo65Fa35). Alternatively, a portion of the 14C atoms released from the olivine grains may have become trapped in synthetic spinel-like minerals that were created in the olivine-flux mixture during the extraction process, or were simply retained in the mixture itself. Regardless, the magnitude of the discrepancy appears to be inversely proportional to the Fe/(Fe+Mg) ratio of the olivine separates. If we apply a simple correction factor based on the chemical composition of the separates, then corrected in situ 14C concentrations are similar to theoretical values at both sites. At this time, we do not know if this agreement is fortuitous or real. Future research should include measurement of in situ 14C concentrations in olivine from known-age basalt flows with different chemical compositions (i.e. more Fe-rich) to determine if this correction is robust for all olivine-bearing rocks. ?? 2010 by the Arizona

  6. Reconstructing Ocean Circulation using Coral (triangle)14C Time Series

    Kashgarian, M; Guilderson, T P

    2001-02-23

    We utilize monthly {sup 14}C data derived from coral archives in conjunction with ocean circulation models to address two questions: (1) how does the shallow circulation of the tropical Pacific vary on seasonal to decadal time scales and (2) which dynamic processes determine the mean vertical structure of the equatorial Pacific thermocline. Our results directly impact the understanding of global climate events such as the El Nino-Southern Oscillation (ENSO). To study changes in ocean circulation and water mass distribution involved in the genesis and evolution of ENSO and decadal climate variability, it is necessary to have records of climate variables several decades in length. Continuous instrumental records are limited because technology for continuous monitoring of ocean currents (e.g. satellites and moored arrays) has only recently been available, and ships of opportunity archives such as COADS contain large spatial and temporal biases. In addition, temperature and salinity in surface waters are not conservative and thus can not be independently relied upon to trace water masses, reducing the utility of historical observations. Radiocarbon in sea water is a quasi-conservative water mass tracer and is incorporated into coral skeletal material, thus coral {sup 14}C records can be used to reconstruct changes in shallow circulation that would be difficult to characterize using instrumental data. High resolution {Delta}{sup 14}C timeseries such as ours, provide a powerful constraint on the rate of surface ocean mixing and hold great promise to augment one time oceanographic surveys. {Delta}{sup 14}C timeseries such as these, not only provide fundamental information about the shallow circulation of the Pacific, but can also be directly used as a benchmark for the next generation of high resolution ocean models used in prognosticating climate. The measurement of {Delta}{sup 14}C in biological archives such as tree rings and coral growth bands is a direct record of

  7. Design and construction of a prototype for the obtention of {sup 32}P; Diseno y construccion de un prototipo para la obtencion de {sup 32}P

    Duarte A, C

    2003-07-01

    The {sup 32} P are a pure emitting radioisotope of maximum energy of 1.71 MeV with half life of 14.28 days that he has applications in the industry, in agriculture, in medicine, in biology and in ecology (6,11,12,13,17,21,22,23,24,25,26,27,28,29,30,31,32 33).The {sup 32} P can be used in the industry like radiotracer in the investigation of some operations and processes and as element of measurement of some industrial meters. In agriculture is used as radiotracer (29) in the investigation of diverse biological processes that have to do with the production of diverse nutritious products. In medicine has uses but very therapeutic mainly in the treatment of some become cancerous (28, 31, 25, 27) in the diagnosis of blood disorders (24) and like part of materials of production of aortic prosthesis (6). The {sup 32} P are also used in the molecular investigation in biology and in genetics (33), and in studies of ecosystems (32) and of DNA (22). One can obtain the {sup 32} P by means of diverse nuclear reactions depending on the material used as matter it prevails, since it doesn't exist in the nature. But anyone in the ways of obtaining it it should imply a process of radiochemical separation that involves so many steps like they are required, depending on the material used as matter prevails, of the purity with which he wants himself to obtain and of the resources that it has available. The objective of this work was design, to build and to prove a prototype to obtain the {sup 32} P to leave of the irradiation of S {alpha} with fast neutrons at experimental level, which implies also to design a process that contemplates diverse stages and procedures for each one of them. The process was outlined in five stages: matter purification prevails, preparation of irradiation capsules, irradiation of irradiation capsules, transport and opening capsules of irradiation and radiochemical separation. In the last stage it was where uses the prototype of radiochemical separation

  8. Some observations indicating a low brain uptake of [3H]Nle11-Substance P

    The studies concerning the problem of whether an exogenous neuropeptide is able to enter the brain tissue were extended to the undecapeptide Substance P (SP). The amount of radioactivity 15 s after intracarotid injection of [3H]Nle11-SP or [14C]inulin was determined in 18 brain regions and the anterior pituitary of male rats. As compared to the reference [14C]inulin, the amount of radioactivity was higher after [3H]Nle11-SP injection (0.233 +- 0.039%, p < 0.001). Statistically significant differences could be found particularly in cortical and caudal areas as well as in the circumventricular organs studied. These observations do not refute the assumption that a low brain uptake of the labelled neuropeptide occurred due to an accumulation within structures of the blood-brain barrier and/or a penetration of the barrier system. (author)

  9. Comparison of the efficacy of biodegradable and non-biodegradable scintillation liquids on the counting of tritium- and [14C]- labeled compounds

    The widespread use of 3H and 14C in research has generated a large volume of waste mixed with scintillation liquid, requiring an effective control and appropriate storage of liquid radioactive waste. In the present study, we compared the efficacy of three commercially available scintillation liquids, Optiphase Hi Safe 3, Ultima-GoldTM AB (biodegradable) and Insta-Gel-XF (non-biodegradable), in terms of [14 C]-glucose and [3 H]-thymidine counting efficiency. We also analyzed the effect of the relative amount of water (1.6 to 50%), radioisotope concentration (0.1 to 100 nCi/ml), pH (2 to 10) and color of the solutions (samples containing 0.1 to 1.0 mg/ml of Trypan blue) on the counting efficiency in the presence of these scintillation liquids. There were few significant differences in the efficiency of 14C and 3H counting obtained with biodegradable or non-biodegradable scintillation liquids. However, there was an 83 and 94% reduction in the efficiency of 14 C and 3 H counting, respectively, in samples colored with 1 mg/ml Trypan blue, but not with 0.1 mg/ml, independent of the scintillation liquid used. Considering the low cost of biodegradable scintillation cocktails and their efficacy, these results show that traditional hazardous scintillation fluids may be replaced with the new safe biodegradable fluids without impairment of 3 H and 14 C counting efficiency. The use of biodegradable scintillation cocktails minimizes both human and environmental exposure to hazardous solvents. In addition, some biodegradable scintillation liquids can be 40% less expensive than the traditional hazardous cocktails. (author)

  10. Behavior of 32P, 35S, 36Cl and 42K in magnesium oxide

    A separation method of 32P from 35S using magnesium oxide as adsorbent of radiophosphorus is described. The behaviour of 32P and 35S, both carrier-free, on magnesium oxide, individually, in dependence of the amount of the adsorbent, of mixing time, of the pH of the loading solution and of potassium chloride concentration, is studied. The separation of the mentioned radioisotopes, using a misture of them, is also analysed. In order to apply this method to the routine production of carrier-free 35S by potassium chloride irradiation, the adsorption behaviour of the chloride and potassium on magnesium oxide using radioactive tracers of these elements, is studied. The separation of 35S from 32P is analyzed by the maximum range of β- particles in aluminum. The absorption curves are presented and compared. (Author)