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Background: Resveratrol is one of the most popular nutrition supplements, especially in the older population segment, yet its safety and health benefits are not fully established. This study aimed at determining bioavailability and the physiological effects of resveratrol delivered by 2 methods in a one senior patient case study. Methods: Bioavailability of resveratrol and blood chemistry parameters following the gastrointestinal and transbuccal intake were measured, respectively, by HPLC in blood and urine, and by blood chemistry analyzer. Results: The fraction of the initially administered resveratrol detected in the blood was over 15 times higher following transbuccal intake than through the gastrointestinal tract. About 36% of the ingested resveratrol was excreted in urine as 3 major metabolites, while only 11% were secreted as major metabolites following the transbuccal intake. The major metabolite in urine peaked at the same time regardless of the method of delivery. Three long-term (31 day) cycles of resveratrol supplementation by transbuccal mucoadhesive film or by ingestion did not result in any noticeable (over 5%) variation of blood chemistry, blood pressure or the overall physical condition of the patient. Conclusion: Bioavailability of resveratrol delivered through oral mucosa may be over one log higher than by swallowing, as determined by the fraction of the initial resveratrol intake in the blood and, under metabolized form, in urine. Lack of resveratrol-associated changes in blood pressure and chemistry following long term supplementation demonstrates good tolerance to high doses of resveratrol in this senior patient case study.

A reference material designed for the determination of anthropogenic and natural radionuclides in sediment, IAEA-384 (Fangataufa Lagoon sediment), is described and the results of certification are presented. The material has been certified for 8 radionuclides (40K, 60Co, 155Eu, 230Th, 238U, 238Pu, 239+240Pu and 241Am). Information values are given for 12 radionuclides (90Sr, 137Cs, 210Pb (210Po), 226Ra, 228Ra, 232Th, 234U, 235U, 239Pu, 240Pu and 241Pu). Less reported radionuclides include 228Th, 236U, 239Np and 242Pu. The reference material may be used for quality management of radioanalytical laboratories engaged in the analysis of radionuclides in the environment, as well as for the development and validation of analytical methods and for training purposes. The material is available from IAEA in 100 g units.

This study provides information on baseline concentrations of the radionuclides Cesium-137, Potassium-40 and Polonium-210 in sea mammals from the Baltic Sea. The radionuclides were analyzed in the liver, kidney and muscle of harbor porpoises, striped dolphins, and gray and ringed seals from the Polish coast by γ- and α-spectrometry. Median (137)Cs activities were 14.8, 13.2 and 23.2 Bq kg(-1) w.w. in the liver, kidney and muscles, respectively. Activities of (40)K and (210)Po in the respective tissues were found to be 79.1, 79.8 and 111 Bq kg(-1) for (40)K and 58.1, 59.2 and 32.9 Bq kg(-1) for (210)Po. The measured (137)Cs concentrations were extraordinarily high in comparison to those reported in sea mammals from other locations. However, dose assessments did not imply health effects from (137)Cs exposure in Baltic Sea mammals. Correlations between (137)Cs tissue activities and reported sea water concentrations highlight the potential use of marine mammals for biomonitoring purposes.

A certified reference material (CRM) for radionuclides in fish sample IAEA-414 (mixed fish from the Irish Sea and North Seas) is described and the results of the certification process are presented. Nine radionuclides (40K, 137Cs, 232Th, 234U, 235U, 238U, 238Pu, 239+240Pu and 241Am) were certified for this material. Information on massic activities with 95% confidence intervals is given for six other radionuclides (90Sr, 210Pb(210Po), 226Ra, 239Pu, 240Pu 241Pu). Less frequently reported radionuclides (99Tc, 129I, 228Th, 230Th and 237Np) and information on some activity and mass ratios are also included. The CRM can be used for quality assurance/quality control of the analysis of radionuclides in fish sample, for the development and validation of analytical methods and for training purposes. The material is available from IAEA, Vienna, in 100 g units.

A simple and rapid method has been developed to determine226Ra in rocks, soils, and sediments. Samples are decomposed by fusion with lithium metaborate and the melt is dissolved in a solution containing sulfates and citric acid. During the dissolution, a fine suspension of mixed barium and radium sulfates is formed. The microcrystals are collected on a membrane filter (pore size 0.1 μm) and analysed in an alpha spectrometer. Application of a133Ba tracer enables us to assess the loss of the analyte, which only rarely exceeds 10%. All analytical operations, beginning from sample decomposition to source preparation for alpha spectrometry, can be accomplished within 1 or 2 h.With uranium determination, the filtrate is spiked with a232U tracer and passed through a column loaded with a Dowex AG (1 x 4) anion-exchange resin in the sulfate form. Interfering elements are eluted with dilute sulfuric acid followed by concentrated hydrochloric acid. Uranium is eluted with water, electrodeposited on silver discs, and analysed in the alpha spectrometer. The method was tested on reference soil and sediment materials and was found to be accurate within the estimated uncertainties.

The activity concentrations of dissolved137Cs have been determined in the water column and137Cs and134Cs in the sediments and the sediment porewaters of the southern Baltic Sea. The mean activity concentration of dissolved137Cs in the Gdansk Deep declined from 109 Bq m−3in June 1986 to 61 Bq m−3in 1999. In sediments, the activity concentrations of137Cs (33-231 Bq kg−1) were highest in muds and the activity concentrations of134Cs were about 6% of the total Cs activity. The Chernobyl contribution to137Cs activity was between 43% and 77%. The porewater activity concentrations of137Cs in muddy sediments were in the range 71 to 3900 Bq m−3and were higher than those in the overlying seawater. The diffusive flux of dissolved137Cs from the muddy sediments was estimated in the range 5 to 480 Bq m−2year−1. The flux of137Cs from sediment porewaters of the southern Baltic Sea was about 45% of the total, including fluxes of137Cs from wet and dry atmospheric deposition and the fluvial inputs. The results were used to elucidate the rate of recovery of the sediments and the waters of the southern Baltic from Chernobyl-derived137Cs.

The results from numerous intercomparison exercises and proficiency tests indicate that the measurement of 90Sr in solid environmental matrices poses a problem to many analysts. The causes of the observed scatter of analytical results are not well understood and therefore difficult to remedy. In order to assess the effect of various analytical operations and measurement routines on the quality of the 90Sr data, the IAEA's Analytical Control Services have organised a proficiency test using a mineral sample spiked at three different levels with known amounts of 90Sr. This proficiency test generated considerable interest from the radioanalytical community as a total of 192 sets of samples were distributed to 158 radioanalytical laboratories world-wide. The reported data were evaluated with respect to their relative bias against the reference value and with respect to their reported overall uncertainty. The major sources of bias leading to overestimated values are ineffective purification procedures, high background values and a lack of statistical control over background values. The major sources of bias leading to an underestimation are overestimated recovery factors in part due to failure to correct for stable Sr in the sample and possibly failure to correct for quenching in liquid scintillation counting. Preliminary results for a small randomly selected group of laboratories are presented.

The characterisation of an intertidal sediment, containing enhanced levels of radioactivity, collected from the Cumbrian coast of the U.K. by the Laboratory of the Government Chemist for the Department of the Environment is described. A wide variety of radiochemical and instrumental techniques were used including α-spectrometry, β-counting, liquid scintillation counting, γ-spectrometry, X-ray spectrometry and mass spectrometry. To derive mean values of the activity concentrations of radionuclides in the material, use was made of the technique developed by Woods and Munster. This technique first critically evaluates data for technical suitability. Then, to avoid excessive manipulation of data, calculation of the weighted (the statistical weighting is the inverse of the squared uncertainties, limited so that no one result contributes more than 50%) and unweighted means is performed, along with a χ2 test. If the value of χ2/(n−1) 2 determinations, 3 with 2 determinations and 2 with single determinations. Emphasis is placed where data appeared to be discrepant (e.g. 40K and 137Cs), where widely different measurement techniques were employed (e.g. the actinides), where there were analytical “difficulties” (e.g. uranium) or where the radionuclide is not commonly measured (e.g. 155Eu, 237Np and 241Pu). The material is now available to laboratories as a reference material and it is anticipated that it will be used to validate existing procedures and to research new methods of analysis.

The kinetics of radiocesium (137Cs) uptake by natural suspended matter collected from coastal waters in the southern Baltic has been studied under laboratory conditions. The uptake of radiocesium from seawater by the suspended matter took place immediately after introduction of the isotope and attained equilibrium within a few hours. Summer and winter suspended matter displayed equal Kd values, indicating similar sorption characteristics of radiocesium. The amounts of radiocesium sorbed from sea water were proportional to the suspended matter concentration studied,i.e. up to 312 mg dry wt dm−3. The relative uptake of radiocesium by live and dead plankton appeared to be the same. The desorption of radiocesium from dead plankton proceeded more rapidly and more intensively than sorption. There are no significant differences between the Kd values for plankton determined in laboratory experiments and those found for plankton populations under field conditions.

Laboratory expriments have demonstrated that radiocaesium can be released in different proportions from Baltic sediments, depending on the type and origin of sediment, contact time and solid-to-liquid phase ratio. Rapidly accumulating sediments in areas affected by river discharge have much higher percentage of exchangeable radiocaesium than slowly accumulating marine sediments. The latter have been shown to {uptake radiocaesium from overlying sea water at high suspended loads. Pronounced radiocaesium gradients at sediment-water interface in Gda\'nsk Bay can be explained by either diffusion from pore water or desorption from sediment particles uprised by waves and/or bottom currents, or a combination of both. Desorption is likely to decrease with age of the sediment.

The main criterion in assaying strontium radionuclides is to obtain radiochemically pure strontium sources for beta-particle counting. Nuclear power plant waters contain both 89 Sr and 90 Sr accompanied by many beta-particle and gamma-ray emitting fission and neutron-activation products. The latter activities can sometimes exceed those of strontium by a factor of 10 7 . Efficient purification procedures must be used to remove these products, preferably at an initial stage of analysis to reduce the radiation risk to personnel. A method has been developed in which a water sample is passed through a prefilter installed on top of an ion-exchange column filled with Dowex-50 resin in H + form. This prefilter is impregnated with ferrocyanides and manganese dioxide and retains most of the interfering radionuclides while the underlying cation-exchanger takes up strontium ions. A few additional purification steps result in a strontium salt that is free from other radioactivity.

Concentration of Zn, Cu, Cd, Pb, Ag, Co, Ni, Cr, Mn and Fe were determined in muscle and liver of three species of penguins and other animals of the antarctic region. Liver was characterized by maximum concentrations of all the metals analyzed. The element levels in the samples assayed are in keeping with those reported previously by other authors. It is assumed that specific food habits of penguins are mainly responsible for elevated Cd levels in livers of these birds.

A new Reference Material (RM) for radionuclides in mussel (Mytilus galloprovincialis) from the Mediterranean Sea (IAEA-437) is described and the results of the certification process are presented. Four radionuclides ( 40K, 234U, 238U, and 239+240Pu) have been certified, and information values on massic activities with 95% confidence intervals are given for nine radionuclides (137Cs, 210Pb(210Po), 226Ra, 228Ra, 228Th, 230Th, 232Th, 235U, and 241Am). Results for less frequently reported radionuclides ( 90Sr, 129I, 238Pu, 239Pu, and 240Pu) are also reported. The RM can be used for quality assurance/quality control of the analysis of radionuclides in mussel samples, for the development and validation of analytical methods and for training purposes. The material is available in 200 g units.

In the paper are presented and discussed results of measurements of plutonium isotopes in the Baltic Sea, sediments and biota following the Chernobyl accident. The average 239, 240Pu level of seawater was found to be 5 mBq m−3 of which 70% constituted filterable forms (

A method was developed for the separation of strontium from large amounts of calcium which does not depend on fuming nitric acid. A sample in the form of mixed carbonates or oxides is stirred into concentrated nitric acid in the proportion 1∶7 w/v. Strontium forms insoluble nitrates while calcium remains in the solution. Two re-precipitation steps combined with an acetone wash yield a very pure strontium salt which is suitable for gravimetric determination of recovery. The method, devised originally for90Sr assay in sea water, can also be applied to solid samples which present analytical problems due to their high calcium content.

Activity coefficients of 137Cs determined during culminating flood waters in August 1997 in the estuary of the Oder River, discharging to the Pomeranian Bay as well as in the coastal and open-seawaters of the Bay, did not show enhanced levels of the nuclide as compared to those measured before the flood. It is thus concluded that the flood did not contribute to releasing the nuclide from eroded soil particles. The bioconcentration factors of 137Cs in the riverine plankton has been found to be one to two orders of magnitude higher than those determined in the Pomeranian Bay plankton.

Zinc, Cu, Cd, Pb, Ag, Ni, Co, Cr, Fe and Mn concentrations in some tissues of crabeater seal ( Lobodon carcinophagus ), leopard seal ( Hydrurga leptonyx ) and Weddell seal ( Leptonychotes weddelli ) from the Antarctic were determined. Distinct inter-tissue differences in metal concentrations in seals were observed; liver contained maximum levels of Zn, Cu, Ag and Mn, whilst kidney showed the highest levels of Cd, Ni and Co. Muscle was characterized by low concentrations of all the elements analyzed. The metal concentrations in the vertebrates analyzed were compared with those for organisms originating from various aquatic areas. Significant correlations were found between the levels of several of the metals analyzed, e.g. between renal and hepatic concentrations of Zn and Cd. Strong relationships between the hepatic concentrations of some metals were found, e.g. CdZn. These two metals also showed a significant coassociation in their renal concentrations. The slope of the regression line for renal Cd/Zn was about three times higher than the hepatic one and this may reflect a relatively high Cd exposure, probably from specific food (squid and krill) provenance, of the seals analyzed.

During the recent Swedish Antarctic research Expedition (SWEDARP 89/89) samples of surface sea water were collected on board the Stena Arctica during steaming between Gothenburg, Sweden and the Antarctic Peninsula. Radio chemical separation was performed for radio caesium on 200 l samples and for plutonium on samples between 200 and 1500 1. The results are compared with those of the GEOSECS expedition in the North and South Atlantic in 1972–73 and the Polish expedition in 1977–78. They show that radio caesium has behaved rather conservatively and that the decrease in surface water concentrations during 16 years mainly is due to physical decay. On the other hand levels of 239+240Pu have decreased by a factor of 4–5 giving a half life of 7–8 years in open Atlantic surface waters.

Radioactivity levels of natural 210Po and anthropogenic 137Cs in sea water and biota (fish and shellfish) have been estimated for the FAO fishing areas on the basis of measurements carried out in recent years. Collective doses resulting from seafood consumption are calculated for each FAO area using radioactivity data for water and biota. Good agreement is observed between the results calculated by these two methods, with the exception of the doses from 210Po via shellfish consumption. The collective effective dose commitment from 137Cs in marine food in 1990 has been estimated at 160 man Sv with an uncertainty of 50%. The corresponding dose from 210Po is 30000 man Sv with an estimated uncertainty of a factor of 5. The results confirm that the dominant contribution to doses derives from natural 210Po in fish and shellfish and that the contribution from anthropogenic 137Cs (mainly originating from nuclear weapons tests) is negligible.

Eight healthy male volunteers were given single doses of 75 mg standard and sustained-release amitriptyline in a double-blind, crossover trial. Systolic time intervals (STI) were measured hourly on drug and base-line days. Plasma amitriptyline and nortriptyline were measured hourly on drug days. To correct for diurnal variations, STI values on drug days were compared with values of base-line days at the same hour. Both formulations of amitriptyline produced initial decreases in heart rate (followed by a return to normal values) and a significant decrease in ventricular electrical systole (QTc), which began before plasma amitriptyline could be detected. One of the eight volunteers showed T wave depression following amitriptyline. The preejection period (PEPc) increased significantly in three of the eight volunteers (max 19%), and this change was due to an increase in true isovolumetric contraction time (TICT). The left ventricular ejection time (LVETc) decreased significantly in all volunteers (5%, p less than 0.001), the change being greater after sustained-release amitriptyline. Standard amitriptyline produced larger changes than sustained-release amitriptyline in QTc and PEPc. The overall increase in the PEP/LVET ratio, indicating an impairment of cardiac function, was twice as large after standard than after sustained-release amitriptyline (38% and 16%, respectively). The possible mechanisms of cardiac effects of amitriptyline are discussed. Our findings indicate that a sustained-release preparation may be safer than a standard preparation of amitriptyline, particularly if there is a risk of cardiac complications.

Within the last five years the International Laboratory of Marine Radioactivity at Monaco has organized seven intercomparison exercises worldwide on natural materials of marine origin comprising sea water (SW-N-2), sediment (SD-N-1/1, SD-N-1/2, SD-N-2), seaweed (AG-B-1) and fish flesh (MA-B-3/1, MA-B-3/2). Results on man-made (54Mn,60Co,65Zn,90Sr,99Tc,134Cs,137Cs,238Pu,239,240Pu,241Am) and natural radionuclides were collected and evaluated. Reference values were established for a number of them. In the paper are discussed various aspects of the intercomparison exercises.

A new method of227Ac determination is based on total sample decomposition, followed by preconcentration as oxalate and hydroxides, and purification from thorium isotopes and rare earths on ion-exchange columns with nitric acid. The actinium is electroplated on stainless-steel discs with near 100% yield from a water/propanol medium and measured by alpha spectrometry.225Ac is used as a yield monitor. An immediate first count gives overall tracer recovery (typically around 80%). A second count two months later gives a sensitive measure of227Ac through its decay products at 5.5–6.1 MeV. Analysis of reference samples gave satisfactory results.

This paper presents the results of an investigation from 1980 to 1985 on the content of 210Po in sea water and its accumulation in southern Baltic plankton. The mean value of the 210Po concentration in sea water has been determined to be about 0.5 mBq dm-3, with the proportion of the dissolved forms being ca 80%. It has been proved that 210Po is accumulated by plankton organisms. The mean 210Po concentration factors calculated on the basis of its content in plankton fall within the range from 5×103 to 4.2×104 and increase as follows: phytoplankton

In the paper are presented results of potassium, uranium, thorium and radium measurements performed on the natural marine sediment sample SD-N-1/2 in the framework of the IAEA-organized worldwide intercomparison exercise. Analytical methods applied in this exercise were evaluated for performance and significance of the observed discrepancies are discussed in the light of statistical and operative criteria. Possible sources of error have been identified in alpha and gamma spectrometric measurements and suggestions are given about how to avoid them. Well characterized reference materials based on natural matrices have been shown helpful in achieving better data comparability in low level measurements of environmental radioactivity.

For the past decade the International Laboratory of Marine Radioactivity at Monaco has been engaged in organizing several intercalibration exercises of radionuclide measurements on various matrices of marine origin. The comparisons of the results obtained in different series of the intercalibration exeercises show that, while the comparability of the plutonium measurements has considerably improved in recent years, the americium measurements do not yet compare favourably transuranic measurements, especially those for americium at low-levels, should still be continued in the future. These series of the intercalibration produced valuable reference materials for which probable concentrations of transuranic nuclides are known. The importance of intralaboratory analytical quality control by using these materials are emphasized for achieving sufficiently consistent and reliable results.

Bojanowski , R. (University of Illinois, Urbana), Elizabeth Gaudy, R. C. Valentine, and R. S. Wolfe . Oxamic transcarbamylase of Streptococcus allantoicus . J. Bacteriol. 87: 75–80. 1964.—An improved colorimetric assay for carbamyl oxamate, which allows the precise measurement of the activity of oxamic transcarbamylase, has been developed. Activity is maximum over the pH range from 8.3 to 8.7. A cation requirement is satisfied by 2.5 × 10 −3 m Mg ++ or Mn ++ . The equilibrium constant for the phosphorolysis of carbamyl oxamic acid is 1.6, corresponding to a negative free energy change of −285 cal per mole.

Gaudy, Elizabeth T. (University of Illinois, Urbana), R. Bojanowski, R. C. Valentine, and R. S. Wolfe . Ureidoglycolate synthetase of Streptococcus allantoicus . I. Measurement of glyoxylate and enzyme purification. J. Bacteriol. 90: 1525–1530. 1965.—A new spectrophotometric method for the determination of glyoxylate is described. The technique is based on measurement of the initial rate of formation of glyoxylic acid phenylhydrazone in neutral solution. Its advantages include rapidity and convenience, suitability for use with mixtures containing acid-labile substrates, and elimination of possibly inhibitory reagents from the enzyme incubation mixture. Ureidoglycolate synthetase, which cleaves ureidoglycolate to glyoxylate and urea, was purified from crude extracts of Streptococcus allantoicus grown on allantoin-containing medium. The purification procedures include treatment with MnCl 2 , fractionation on calcium phosphate gel, fractional precipitation with ammonium sulfate, and column chromatography on diethylaminoethyl cellulose. The final enzyme preparation was purified 77-fold and contained 35% of the total activity of the extract.

The effects of captopril versus placebo on oxygen consumption in the exercising leg have been examined using Doppler measurements of femoral flow and arteriovenous oxygen difference. Twenty patients with heart failure were randomized to captopril 25 mg (N = 10) or placebo (N = 10). Maximal supine exercise of one leg was performed before treatment and again 1 h and 4 h afterwards. Systemic haemodynamic variables were unaffected by placebo, but captopril increased stroke index at peak exercise from 26 +/- 3 to 34 +/- 3 ml beat-1 m-2 and reduced pulmonary artery wedge pressure from 26 +/- 3 to 16 +/- 3 mmHg (P less than 0.05). Despite the captopril-induced improvement in left ventricular function, exercise duration did not increase significantly and peak values for femoral flow (1059 +/- 178 to 938 +/- 134 ml min-1, P = NS), and oxygen consumption (134 +/- 26 to 111 +/- 18 ml min-1, P = NS) in the exercising leg were unaffected. Cutaneous flow, as reflected by skin temperature (27.5 +/- 0.4 to 27.6 +/- 0.4 degrees C, P = NS), was also unaffected. In the patients randomized to captopril, the acute improvement in left ventricular function was abbreviated and, after 4 h, all variables had returned towards baseline. Moreover, when the invasive studies were repeated after four weeks chronic treatment responsiveness to converting enzyme inhibition had attenuated and there were no detectable differences between the captopril and placebo groups. These data have demonstrated an acute captopril-induced improvement in left ventricular function in patients with congestive heart failure. Nevertheless the beneficial acute response was abbreviated predicting the development of early tolerance. Oxygen delivery to the exercising leg showed no tendency to increase either acutely when left ventricular function was significantly improved, or chronically when systemic responsiveness had attenuated. Thus irrespective of its effects on left ventricular function, captopril does not increase nutritive flow to exercising skeletal muscle in congestive heart failure.