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Sample records for absorption distribution excretion

  1. The absorption, distribution, metabolism and excretion of procyanidins.

    Zhang, Liang; Wang, Yijun; Li, Daxiang; Ho, Chi-Tang; Li, Junsong; Wan, Xiaochun

    2016-03-16

    Procyanidins (PAs) are polyphenols in plant food that have many health benefits, including cancer prevention, cardiovascular protection and diabetes prevention. PAs have been known to have low oral bioavilability. In this review, we summarize the published results on the ADME (absorption, distribution, metabolism and excretion) of PAs in vivo and in vitro. After oral administration, in the stomach the decomposition of PAs is highly dependent on the pH value of gastric juice, which is also affected by food intake. In the small intestine, PA polymers and oligomers with DP > 4 are not directly absorbed in vivo, but minor PA monomers and dimers could be detected in the plasma. Methylated and glucuronidated PA dimers and monomers are the main metabolites of PAs in plasma. In the colon, PAs are catabolized by colonic microflora into a series of low molecular weight phenolic acids, such as phenyl valerolactone, phenylacetic acids and phenylpropionic acids. We reviewed the degradation of PAs in gastric digestion, the absorption of PAs in the small intestine and the metabolic pathway of PAs by colonic microflora. To clearly explain the in vivo pharmacokinetics of PAs, a systematic comparative analysis on previously published data on PAs was conducted. PMID:26814915

  2. Absorption, distribution and excretion of the colour fraction of Caramel Colour IV in the rat.

    Selim, S; Chappel, C I; Schoenig, G P

    1992-05-01

    Caramel Colour IV prepared from [U-14C]glucose was ultrafiltered in order to isolate the high molecular weight colour fraction (HMCF). The colour fraction that was non-permeable to a 10,000-Da porosity membrane, contained 84% of the colour, 22% of the solids and 24% of the radioactivity of the [14C]Caramel Colour IV. The absorption, distribution and excretion of [14C]HMCF were evaluated in male rats after administration of single or multiple oral doses of the material at a dosage level of 2.5 g/kg body weight. Rats on the multiple oral dosage regimen were given unlabelled HMCF in their drinking water for 13 days before the administration of a bolus dose of [14C]HMCF on day 14. On both dosage regimens, the predominant route of excretion was by way of the faeces. Less than 3% of the administered radioactivity was excreted in the urine and only a negligible amount was found in the expired air. More than 99% of the administered radioactivity was excreted within 96 hr. The principal tissues in which radioactivity was found were the mesenteric lymph nodes, liver, kidney and tissues of the gastro-intestinal tract. No major differences were observed in the absorption, distribution or excretion patterns between the single and multiple oral dose regimens. PMID:1644386

  3. Comparative absorption, distribution, and excretion of titanium dioxide and zinc oxide nanoparticles after repeated oral administration

    Cho, Wan-Seob; Kang, Byeong-Cheol; Lee, Jong Kwon; Jeong, Jayoung; Che, Jeong-Hwan; Seok, Seung H

    2013-01-01

    BACKGROUND:The in vivo kinetics of nanoparticles is an essential to understand the hazard of nanoparticles. Here, the absorption, distribution, and excretion patterns of titanium dioxide (TiO2) and zinc oxide (ZnO) nanoparticles following oral administration were evaluated.METHODS:Nanoparticles were orally administered to rats for 13 weeks (7 days/week). Samples of blood, tissues (liver, kidneys, spleen, and brain), urine, and feces were obtained at necropsy. The level of Ti or Zn in each sam...

  4. Identification of Absorption, Distribution, Metabolism, and Excretion (ADME) Genes Relevant to Steatosis Using a Differential Gene Expression Approach

    Absorption, distribution, metabolism, and excretion (ADME) parameters represent important connections between exposure to chemicals and the activation of molecular initiating events of Adverse Outcome Pathways (AOPs) in cellular, tissue, and organ level targets. ADME parameters u...

  5. Absorption, tissue distribution, and excretion of tritium-labeled ivermectin in cattle, sheep, and rat

    Tritium-labeled ivermectin was studied in cattle, sheep, and rat for absorption, tissue residue distribution, and excretion at doses of 0.3 mg/kg of body weight. The drug was absorbed by various dosing routes. By intraruminal and subcutaneous dosing routes, highest tissue residues were present in fat and liver of cattle, with half-lives of 6-8 and 4-5 days, respectively. Shorter half-lives (1-2 days) were observed in sheep and rat. The tissue residue distribution pattern was essentially the same for all species studied and similar in male and female rats. With doses of tritium-labeled avermectin B1a ranging from 0.06 to 7.5 mg/kg of body weight, plasma and tissue residue concentrations increased proportionally with the dose. When ivermectin was administered by various routes (ip, sc, iv, oral, and intraruminal), blood residue levels converged to 20-50 ppb 4 h after dosing and then depleted at similar rate regardless of the dosing route. Ivermectin was excreted primarily in the feces, with only less than 2% of the doses being eliminated in the urine in all three species studied

  6. Studies on absorption, distribution, excretion and metabolism of 3H-1α-hydroxycholecalciferol in vitamin D deficient rats

    The absorption, distribution, excretion and metabolism of 2-3H-1α-OH-D3 (4.2 Ci/mmol) were studied in vitamin D deficient rats in comparison with the normal rats after oral or intravenous dosing. (1) Maximum blood level of administered radioactivity was observed at 8 hours after oral administration with apparent half life of 3.8 days. This blood level was higher than that in normal rat. (2) As in the normal rat, administered radioactivity was distributed relatively high in the liver, while any other specific distribution or accumulation was not observed in the another tissues, which was consistent to the finding in the normal rat. The tissue levels of the radioactivity were higher than these in the normal rat. (3) Urinary excretion of administered radioactivity was significantly higher, fecal and biliary excretion was significantly lower than that in the normal rat after intravenous dosing. (4) Relative percentage of 3H-1α, 25-(OH)2-D3 content to 3H-1α-OH-D3 content in tissues and blood was higher than that in the normal one. Above results suggest that in the vitamin D deficient state, the tissue accumulation of 1α-OH-D3 was significantly augmented than in the normal rat, thus resulting increased bioavailability of its active metabolite, 1α, 25-(OH)2-D3. (author)

  7. Absorption, distribution, metabolism, and excretion of the novel antibacterial prodrug tedizolid phosphate.

    Ong, Voon; Flanagan, Shawn; Fang, Edward; Dreskin, Howard J; Locke, Jeffrey B; Bartizal, Kenneth; Prokocimer, Philippe

    2014-08-01

    Tedizolid phosphate is a novel antibacterial prodrug with potent activity against Gram-positive pathogens. In vitro and in vivo studies demonstrated that the prodrug is rapidly converted by nonspecific phosphatases to the biologically active moiety tedizolid. Single oral dose radiolabeled (14)C-tedizolid phosphate kinetic studies in human subjects (100 µCi in 204 mg tedizolid phosphate free acid) confirmed a rapid time to maximum tedizolid concentration (Tmax, 1.28 hours), a long terminal half-life (10.6 hours), and a Cmax of 1.99 µg/ml. Metabolite analysis of plasma, fecal, and urine samples from rats, dogs, and humans confirmed that tedizolid is the only measurable metabolite in plasma after intravenous (in animals only) or oral administration and that tedizolid sulfate is the major metabolite excreted from the body. Excellent mass balance recovery was achieved and demonstrated that fecal excretion is the predominant (80-90%) route of elimination across species, primarily as tedizolid sulfate. Urine excretion accounted for the balance of drug elimination but contained a broader range of minor metabolites. Glucuronidation products were not detected. Similar results were observed in rats and dogs after both intravenous and oral administration. The tedizolid metabolites showed less potent antibacterial activity than tedizolid. The observations from these studies support once daily dosing of tedizolid phosphate and highlight important metabolism and excretion features that differentiate tedizolid phosphate from linezolid. PMID:24875463

  8. Absorption, distribution and excretion of inhaled hydrogen fluoride in the rat

    Morris, J.B.

    1979-01-01

    Rats were subjected to whole body HF exposure for 6 hrs or to nose-only HF exposure for 1 hr. Total and/or ionic fluoride concentrations in selected tissues were determined at various times following exposure. In rats sacrificed 6 hrs after whole body exposure, dose-dependent increases in lung, plasma, and kidney total and ionic fluoride concentration occurred. Rats excreted more fluoride in the urine after whole body exposure than could be explained by the amount of HF inhaled. Considerable evidence suggests that airborne HF deposits on fur and is then ingested due to preening activity. Urinary fluoride excretion was increased by nose-only exposure. The urinary fluoride excretion accounted for approximately twice the fluoride estimated to be inhaled during exposure. Tissue fluoride concentrations were elevated immediately after nose-only exposure. Fluoride concentrations in lung and kidney returned to control levels within 12 hrs. Plasma fluoride concentration was slightly elevated 24 hrs after the start of the 1 hr exposure but was at control levels at 96 hrs. Immediately following nose-only exposure, lung ionic fluoride concentrations were less than plasma ionic fluoride concentrations suggesting that the fluoride in the lung had reached that site via plasma transport rather than by inhalation. A dose-dependent increase in plasma ionic fluoride concentration occurred after upper respiratory tract HF exposure providing strong evidence that fluoride is absorbed systemically from that site. The plasma ionic fluoride concentration after upper respiratory tract exposure was of sufficient magnitude to account for the plasma fluoride concentrations observed in intact nose-only exposed rats. (ERB)

  9. Determination of drug-like properties of a novel antileishmanial compound: In vitro absorption, distribution, metabolism, and excretion studies

    Mondal Susanta

    2009-01-01

    Full Text Available In drug discovery research, the compounds should not only to be potent and selective but also must possess acceptable pharmacokinetic properties such as absorption, distribution, metabolism, and excretion (ADME to increase success rate in clinical studies. Objective: Exploration of drug-like properties of 2-(2-methylquinolin-4-ylamino-N-phenyl acetamide, a potent antileishmanial compound by performing some in vitro ADME experiments along with validation of such studies. Materials and Methods: Experimental protocols were established and validated for stability (in PBS pH7.4, simulated gastric and intestinal fluid, solubility, permeability, distribution coefficient (Log D, plasma protein binding and metabolism by rat liver microsomes by using spectrophotometer or HPLC. Methods were considered valid if the results of the standard compounds matched with reported results or within acceptable range or with proper ranking (high-medium-low. Results: The compound was found to be stable (>95% remaining in all stability studies and aqueous solubility was 299.7 ± 6.42 μM. The parallel artificial membrane permeability assay (PAMPA indicated its medium permeability (Log Pe = -5.53 ± 0.01. The distribution coefficients (Log D in octanol/PBS and cyclohexane/PBS systems were found to be 0.54 and -1.33, respectively. The plasma protein binding study by the equilibrium dialysis method was observed to be 78.82 ± 0.13% while metabolism by Phase-I enzymes for 1 hour at 37°C revealed that 36.07 ± 4.15% of the compound remained after metabolism. Conclusion: The methods were found to be very useful for day-to-day ADME studies. All the studies with the antileishmanial compound ascertained that the compound bears optimum pharmacokinetic properties to be used orally as a potential drug for the treatment of leishmaniasis.

  10. Evaluation of in vitro absorption, distribution, metabolism, and excretion (ADME) properties of mitragynine, 7-hydroxymitragynine, and mitraphylline.

    Manda, Vamshi K; Avula, Bharathi; Ali, Zulfiqar; Khan, Ikhlas A; Walker, Larry A; Khan, Shabana I

    2014-05-01

    Mitragyna speciosa (kratom) is a popular herb in Southeast Asia, which is traditionally used to treat withdrawal symptoms associated with opiate addiction. Mitragynine, 7-hydroxymitragynine, and mitraphylline are reported to be the central nervous system active alkaloids which bind to the opiate receptors. Mitraphylline is also present in the bark of Uncaria tomentosa (cat's claw). Several therapeutic properties have been reported for these compounds but limited information is available on the absorption and distribution properties. This study focuses on evaluating the absorption, distribution, metabolism, and excretion (ADME) properties of these compounds and their effect on major efflux transporter P-glycoprotein, using in vitro methods. Quantitative analysis was performed by the Q-TOF LC-MS system. Mitragynine was unstable in simulated gastric fluid with 26 % degradation but stable in simulated intestinal fluid. 7-Hydroxymitragynine degraded up to 27 % in simulated gastric fluid, which could account for its conversion to mitragynine (23 %), while only 6 % degradation was seen in simulated intestinal fluid. Mitraphylline was stable in simulated gastric fluid but unstable in simulated intestinal fluid (13.6 % degradation). Mitragynine and 7-hydroxymitragynine showed moderate permeability across Caco-2 and MDR-MDCK monolayers with no significant efflux. However, mitraphylline was subjected to efflux mediated by P-glycoprotein in both Caco-2 and MDR-MDCK monolayers. Mitragynine was found to be metabolically stable in both human liver microsomes and S9 fractions. In contrast, both 7-hydroxymitragynine and mitraphylline were metabolized by human liver microsomes with half-lives of 24 and 50 min, respectively. All three compounds exhibited high plasma protein binding (> 90 %) determined by equilibrium dialysis. Mitragynine and 7-hydroxymitragynine inhibited P-glycoprotein with EC50 values of 18.2 ± 3.6 µM and 32.4 ± 1.9 µM, respectively

  11. Influence of dietary calcium on phosphorus absorption and excretion and on phosphorus-33 distribution in laying hens

    An experiment was conducted using isotope-dilution and comparative balance techniques to estimate urinary and fecal P excretion of laying hens fed different levels of dietary Ca. Two levels of dietary Ca (3.46 and 4.2%) were fed to eight hens for 30 days. After 30 days, 50 microCi of the radioisotope 33P was injected intramuscularly to label endogenous P. On the 2nd day after 33P dosing and at 1 h postoviposition, plasma, liver, kidney, femur bone, whole egg, ileum, ileal digesta, and excreta samples were collected from each hen. Results showed a favorable effect of increasing dietary Ca consumption (2.91 vs 3.57 g/hen per day): femur ash increased (P less than .08), excreta P decreased (P less than .03), and urinary P decreased (P less than .06). The P content of ileal digesta was not affected by dietary Ca intake, but excreta P was greater for hens consuming less Ca, indicating that, during the collection period, excretion of P in urine was increased by the low Ca diet. Endogenous P secretions constituted less than 1% of the P in ileal digesta and excreta samples and this proportion was not changed by dietary Ca consumed

  12. Absorption, distribution, metabolism and excretion of selenium following oral administration of elemental selenium nanoparticles or selenite in rats

    Löschner, Katrin; Hadrup, Niels; Hansen, Marianne;

    2014-01-01

    A suspension of nanoparticles of BSA-stabilized red amorphous elemental selenium (Se) or an aqueous solution of sodium selenite was repeatedly administered by oral gavage for 28 days at 0.05 mg/kg bw/day (low dose) or at 0.5 mg/kg bw/day (high dose) as Se to female rats. Prior to administration......, the size distribution of the Se nanoparticles was characterized by dynamic light scattering and transmission electron microscopy, which showed that the particles’ mean diameter was 19 nm and ranged in size from 10-80 nm. Following administration of the high dose of Se nanoparticles or selenite the...... concentration of Se was determined by ICP-MS in liver, kidney, urine, feces, stomach, lungs, plasma at µg/g level and in brain and muscle tissue at sub-µg/g level. In order to test if any elemental Se was present in liver, kidney or feces, an in situ derivatization selective to elemental Se was made by...

  13. Alkali absorption and citrate excretion in calcium nephrolithiasis

    Sakhaee, K.; Williams, R. H.; Oh, M. S.; Padalino, P.; Adams-Huet, B.; Whitson, P.; Pak, C. Y.

    1993-01-01

    The role of net gastrointestinal (GI) alkali absorption in the development of hypocitraturia was investigated. The net GI absorption of alkali was estimated from the difference between simple urinary cations (Ca, Mg, Na, and K) and anions (Cl and P). In 131 normal subjects, the 24 h urinary citrate was positively correlated with the net GI absorption of alkali (r = 0.49, p mEq/day). Both urinary citrate and net GI alkali absorption increased, yielding a significantly positive correlation (r = 0.62, p reduced citrate excretion was largely dietary in origin as a result of low net alkali absorption (from a probable relative deficiency of vegetables and fruits or a relative excess of animal proteins).

  14. Alkali absorption and citrate excretion in calcium nephrolithiasis

    Sakhaee, K.; Williams, R. H.; Oh, M. S.; Padalino, P.; Adams-Huet, B.; Whitson, P.; Pak, C. Y.

    1993-01-01

    The role of net gastrointestinal (GI) alkali absorption in the development of hypocitraturia was investigated. The net GI absorption of alkali was estimated from the difference between simple urinary cations (Ca, Mg, Na, and K) and anions (Cl and P). In 131 normal subjects, the 24 h urinary citrate was positively correlated with the net GI absorption of alkali (r = 0.49, p < 0.001). In 11 patients with distal renal tubular acidosis (RTA), urinary citrate excretion was subnormal relative to net GI alkali absorption, with data from most patients residing outside the 95% confidence ellipse described for normal subjects. However, the normal relationship between urinary citrate and net absorbed alkali was maintained in 11 patients with chronic diarrheal syndrome (CDS) and in 124 stone-forming patients devoid of RTA or CDS, half of whom had "idiopathic" hypocitraturia. The 18 stone-forming patients without RTA or CDS received potassium citrate (30-60 mEq/day). Both urinary citrate and net GI alkali absorption increased, yielding a significantly positive correlation (r = 0.62, p < 0.0001), with the slope indistinguishable from that of normal subjects. Thus, urinary citrate was normally dependent on the net GI absorption of alkali. This dependence was less marked in RTA, confirming the renal origin of hypocitraturia. However, the normal dependence was maintained in CDS and in idiopathic hypocitraturia, suggesting that reduced citrate excretion was largely dietary in origin as a result of low net alkali absorption (from a probable relative deficiency of vegetables and fruits or a relative excess of animal proteins).

  15. Quantitative aspects of phosphorus absorption and excretion in horses

    Bueno, Ives Claudio da Silva; Abdalla, Adibe Luiz; Vitti, Dorinha Miriam Silber Schmidt [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil). Lab. de Nutricao Animal]. E-mails: icsbueno@cena.usp.br; abdalla@cena.usp.br; dovitti@cena.usp.br; Furtado, Carlos Eduardo [Universidade Estadual de Maringa, PR (Brazil). Dept. de Zootecnia]. E-mail: cefurtado@uem.br

    2007-07-01

    Phosphorus (P) is one of the most polluting nutrients because of high husbandry concentrations in restricted areas. The present study compiles data from previous studies dealing with true digestibility of different P levels in diets for horses. Database consisted of results from two experiments carried out at the Centre for Nuclear Energy in Agriculture (CENA/USP), using horses fed different levels of P (n=28). True absorption of phosphorus was determined by isotopic dilution technique, using {sup 32}P as tracer. All parameters (P{sub ING}: ingested P; P{sub ABS}: absorbed P; P{sub FECTOT}: total faecal P excretion; P{sub FECENDO}: endogenous faecal P; P{sub URI}: total urinary excretion; and P{sub RET}: retained P) were normalized according to body weight (BW) and linear and quadratic regressions between P{sub ING} and the other parameters were tested. No quadratic effect was observed. P{sub ING} ranged from 41 to 264 mg/kg BW. Faecal P excretion was affected by intake, analysing by total (P{sub FECTOT} = 0.888 (S.E. 0.058) P{sub ING} - 29.40 (S.E. 8.14) (P<0.0001; RMSE=20.37; R{sup 2}=0.90) or by endogenous fraction (P{sub FECENDO} = 0.095 (S.E. 0.029) P{sub ING} + 12.10 (S.E. 4.16) (P=0.0034; RMSE=10.41; {sup R}2=0.29). Urinary P excretion was not affected by intake (P=0.35), although ranging from 0.06 to 59.20 mg/kg BW. The same occurred for P{sub RET} (P=0.25) ranging from -13.69 to 88.78 mg/kg BW. P absorption also was affect by P intake (P{sub ABS} = 0.195 (S.E. 0.060) P{sub ING} + 42.19 (S.E. 8.45) (P=0.0031; RMSE=21.15; R{sup 2}=0.29). The present study showed that only a small part of ingested P was absorbed, i.e. most of ingested P was excreted via faeces, contributing for environmental pollution. (author)

  16. Tissue distribution and excretion pattern of 51Cr in animals

    To study distribution and excretion pattern of chromium, 51CrCl3 was orally administered in doses of 66.6 μCi to each rat. Lungs, liver and testis accumulated relatively higher radioactivity earlier and this accumulation persisted in liver and testis for 192 hr. The lungs, heart muscles and gall bladder showed a gradual decline after initial uptake whereas in kidney and spleen it continued to increase as a function of time. Uptake of 51Cr per unit weight of the small intestine was greater than the stomach and the large intestine. On an average, 70.15 percent of the orally administered 51Cr was excreted in faeces within 192 hr of dosing. In the second experiment, six male kids weighing 23.87 kg, on an average, were given orally 500 μCi of 51Cr. Kids were maintained on concentrate mixture and green berseem which contained 0.43 ppm and 0.195 ppm chromium, respectively. The balance studies revealed that 94.93 percent of the total 51Cr dose was excreted in the faeces and 1.93 percent in the urine during 7 day period. Net absorption of 51Cr was, however, only 9.0 percent. (auth.)

  17. Pharmacokinetics, tissue distribution, and excretion of zinc oxide nanoparticles

    Baek M

    2012-06-01

    Full Text Available Miri Baek,1,* Hae-Eun Chung,1,* Jin Yu,1,* Jung-A Lee,1 Tae-Hyun Kim,2 Jae-Min Oh,2 Won-Jae Lee,3 Seung-Min Paek,3 Jong Kwon Lee,4 Jayoung Jeong, 4 Jin-Ho Choy,5 Soo-Jin Choi1 1Department of Food Science and Technology, Seoul Women's University, Seoul, 2Department of Chemistry and Medical Chemistry, College of Science and Technology, Yonsei University, Wonju, Gangwondo; 3Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, Taegu, 4Toxicological Research Division, National Institute of Food and Drug Safety Evaluation, Chungchungbuk-do, 5Center for Intelligent Nano-Bio Materials, Department of Bioinspired Science and Department of Chemistry and Nano Science, Ewha Womans University, Seoul, Republic of Korea*These authors contributed equally to this workBackground: This study explored the pharmacokinetics, tissue distribution, and excretion profile of zinc oxide (ZnO nanoparticles with respect to their particle size in rats.Methods: Two ZnO nanoparticles of different size (20 nm and 70 nm were orally administered to male and female rats, respectively. The area under the plasma concentration-time curve, tissue distribution, excretion, and the fate of the nanoparticles in organs were analyzed.Results: The plasma zinc concentration of both sizes of ZnO nanoparticles increased during the 24 hours after administration in a dose-dependent manner. They were mainly distributed to organs such as the liver, lung, and kidney within 72 hours without any significant difference being found according to particle size or rat gender. Elimination kinetics showed that a small amount of ZnO nanoparticles was excreted via the urine, while most of nanoparticles were excreted via the feces. Transmission electron microscopy and x-ray absorption spectroscopy studies in the tissues showed no noticeable ZnO nanoparticles, while new Zn-S bonds were observed in tissues.Conclusion: ZnO nanoparticles of different size were not easily

  18. Docking mode of delvardine and its analogues into the p66 domain of HIV-1 reverse transcriptase: screening using molecular mechanics-generalized born/surface area and absorption, distribution, metabolism and excretion properties

    Dipankar Sengupta; Deeptak Verma; Pradeep K Naik

    2007-12-01

    Delvardine and its structural derivatives are important non-nucleoside HIV-1 reverse transcriptase inhibitors (NNRTIs). In this work, 15 delvardine analogues were studied. A free energy-of-binding (FEB) expression was developed in the form of an optimized linear combination of van der Waal (vdW), electrostatic, solvation and solvent-accessible surface area (SASA) energy terms. The solvation energy terms estimated by generalized born/surface area (GB/SA) play an important role in predicting the binding affinity of delvardine analogues. Out of 15 derivatives, substitution of CH3 with H at the Y and R positions, as well as substitution of SO2CH3 with only CH2 at the Z position in S2, S8 and S12 analogues, were found to be the most potent (glide score = –7.60, –8.06 and –7.44; pIC50 = 7.28, 7.37 and 7.64) in comparison with the template delvardine (which is used currently as the drug candidate). All the three analogues also passed the absorption, distribution, metabolism and excretion (ADME) screening and Lipinski’s rule of 5, and have the potential to be used for second-generation drug development. The work demonstrates that dock molecular mechanics-generalized born/surface area (MM–GB/SA–ADME) is a promising approach to predict the binding activity of ligands to the receptor and further screen for a successful candidate drug in a computer-aided rational drug design.

  19. The distribution and excretion of nerve growth factor in mice

    Nerve growth factor (NGF) was iodolabelled with chloramine-T method and its distribution and excretion in mice were investigated. The results showed that the highest levels were found in superior cervical ganglia, thyroid, bile, kidneys and adrenals between 20-30 min after injection, and the peak time in most tissues was also found at 20-30 min. About 72.55% of the injected dose was excreted in stool and urine, among them 65.6% was excreted in urine and only 7.0% in stool within 72 h after intramuscular injection

  20. Tissue distribution, excretion and blood distribution of [3H]-acetylshikonin in mice by sample oxidizer

    Objective: To study the tissue distribution, excretion and blood distribution of [3H]-acetylshikonin in mice by Sample Oxidizer pretreatment technology. Methods: After 0.5% carboxymethyl cellulose suspension containing [3H] - acetylshikonin was administered by gastric gavage at the dose of 120 mg/kg(2.96 x 107 Bq/kg), the tissue, feces, urine and blood samples of the mice were collected. The samples were pretreated by Sample Oxidizer. The radioactivity was determined by Liquid Scintillation Analyzer Tn-Card 29007R. Results: After oral administration of [3H]-acetylshikonin 120 mg/kg with 2.96 x 107 Bq/kg to mice, [3H]-acetylshikonin was mainly distributed in the stomach and intestine, secondarily in the gallbladder, liver, kidneys, lungs, and least in the brain and spinal cord. The cumulative radioactivity rate of the feces and urine was(68.5±3.3)% and (17.6±3.1)% within 271 h, respectively. The total excretion rate was (86.1±5.5)%. Besides, the exploratory study was carried out on acetylshikonin the existing form of in blood, allocation in plasma and blood cells, binding mode and binding rates of plasma proteins. Conclusions: Acetylshikonin has a relatively low absorption rate and wide distribution in mice, and is excreted completely more by fecal route than by urine. Acetylshikonin exits as a binding form in mouse blood. Allocation of acetylshikonin in mouse plasma and blood cells is nearly 4:1. Plasma protein binding rates of three levels (high, medium and low) are (94.7±O.44)%, (94.7±0.29)% and (95.4±0.13)%, respectively. The binding between acetylshikonin and human plasma protein is the coexistence of covalent bonding and hydrophobic interaction. (authors)

  1. Viscous Food Matrix Influences Absorption and Excretion but Not Metabolism of Blackcurrant Anthocyanins in Rats

    Walton, M.C.; Hendriks, W.H.; Broomfield, A.M.; McGhie, T.K.

    2009-01-01

    The aim of the present study was to investigate the effect of a simultaneous intake of food and anthocyanins (ACNs) on ACN absorption, metabolism, and excretion. Blackcurrant ACNs (BcACNs) were dissolved in water with or without the addition of oatmeal and orally administered to rats, providing appr

  2. Absorption and excretion of black currant anthocyanins in human and Watanabe Heritable Hyperlipidemic rabbits

    Nielsen, I. L.. F.; Ravn-Haren, Gitte; Dragsted, L. O.;

    2003-01-01

    Anthocyanins are thought to protect against cardiovascular diseases. Watanabe heritable hyperlipidemic (WHHL) rabbits are hypercholesterolemic and used as a model of the development of atherosclerosis. To compare the uptake and excretion of anthocyanins in humans and WHHL rabbits, single-dose black...... currant anthocyanin studies were performed. Procedures for workup and analyses of urine and plasma samples containing anthocyanins were developed with high recoveries (99 and 81%, respectively) and low limits of quantification (greater than or equal to 6.6 and greater than or equal to 1.1 nM, respectively......). The excretion and absorption of anthocyanins from black currant juice were found to be within the same order of magnitude in the two species regarding urinary excretion within the first 4 h (rabbits, 0.035%; humans, 0.072%) and t(ma)x (rabbits, similar to30 min; humans, similar to45 min). A food...

  3. Determination of iron absorption and excretion by whole-body counting

    Using a whole-body counter, the authors have studied 59Fe absorption and loss in 8 normal subjects and in 30 iron deficient patients. Results showed that whole-body counting provided an excellent and simple method for iron retention measurements, obviating many inaccuracies of previous technic. Normal absorption of radio iron with this procedure has ranged from 9 per cent to 20 per cent of the administered tracer in normal subjects, with a mean of 15 per cent. A significant increase in 59Fe absorption was noted in 21 iron-deficient patients in whom the retention ranged from 40 to 100 per cent. However, 3 iron-deficient patients were found to have low absorption, and their severe iron deficiency could be correlated with this defect in absorption. This method permits also the determination of the rate of iron excretion during the following months and therefore the study of the mechanism of some pathological loss. (authors)

  4. Alginate enhances excretion and reduces absorption of strontium and cesium in rats

    Alginate (ALA), which is an intercellular polysaccharide associated with brown algae, is used as a food additive, a health food and a medicine. Here, we first examined the adsorption of strontium (Sr) and cesium (Cs) by ALA in vitro, and then evaluated the effects of ALA on absorption and excretion of Sr and Cs in rats, in order to evaluate its potential usefulness for minimizing radiation damage from materials released after a nuclear accident. Both Sr and Cs were concentration-dependently adsorbed by sodium alginate (ALA-Na) in vitro. In rats given diet containing either ALA-Na or calcium alginate (ALA-Ca) for two weeks, the plasma concentration of Sr gradually decreased compared with the controls (normal diet); however, in the case of Cs, the plasma concentration was decreased only in the ALA-Ca group, but not the ALA-Na group. Moreover, we examined the effect of preadministration of diet containing either ALA-Na or ALA-Ca on absorption of Sr and Cs administered orally as the chloride salts to rats. Absorption of both Sr and Cs was reduced in the ALA-Ca group, while absorption of only Sr was reduced in the ALA-Na group. Safety assessments indicated that ALA-Ca is safer than ALA-Na. These results indicate that ALA-Ca reduces absorption and promotes excretion of both Sr and Cs, while ALA-Na does so only for Sr. (author)

  5. Tissue distribution and excretion of n-methyl-2-pyrolidone in male and female rats

    N-methyl-2-pyrrolidone (NMP) belongs to solvents widely used in the petrochemical industry a well as in the production of pesticides, veterinary drugs and paint removers. NMP is easily absorbed from respiratory tract, digestive system and through the skin. It is a compound of slight acute toxicity that also displays moderate irritating activity. The aim of this study was to assess tissue distribution and excretion following a single intraperitoneal NPM administration. Tissue distribution and excretion of NMP following administration of a single dose of 250 mg/kg body weight (350 kBq/rat) was investigated using 14C. Blood plasma (6 rats per time point) were sampled up to 72 h after administration and determination of radioactivity. Male and female rats (4 animals per time point) were decapitated at appropriate time intervals and examined tissues were removed for determination of radioactivity. Excretion of 14C in urine and feces were also measured. All radioactivity measurements were carried out using a Rakbetta 1209 (LKB, Sweden) liquid scintillation counter. The highest in 14C activity in tissues and internal organs of female and male rats was observed 4 h after administration of the compound. The highest accumulation was in dected in the muscles and fat tissue as well as the liver and testicles. During 72 h following administration, approximately 80% of the dose was excreted in urine. Elimination of the compound in feces was far less significant: only about 5% of the dose was excreted at once. The results of the study indicate that there are no significant differences in 14C-NMP tissue distribution between male and female rats; NPM absorption from the peritoneal cavity to blood is rapid, disappearance from plasma is monophase and kidneys are the main route of excretion of NMP and/ or its metabolites from the rat body after administration of a dose equal to 10% of L50. The ability to accumulate NMP and/or its metabolites in testes and seminal vesicles may be the

  6. Accumulation, distribution and excretion of 134Cs and 65Zn by the green mussels (Perna Viridis)

    Two important radionuclides 134Cs and 65Zn were applied to study the accumulation, distribution and excretion of radioactive nuclides in organs and tissues of green mussel Perna Viridis. the results showed that the uptake rate of 134Cs by green mussels was very low and the concentration factor (CF) for 134Cs in the byssus approximated to 1. This CF value was lower than that of other tissues and organs of mussels, but its excretion rate was much higher than that of soft tissues. It was also found that the byssus of mussels had a special ability to accumulate 65Zn. Concentration factor (CF) for 65Zn in the byssus could reach as high as 900, which was much higher than that of any other tissues. However, its excretion rate was lower than that of other tissues and organs. The uptake rate of 65Zn by soft tissues was markedly higher than that of 134Cs. The mussels could also highly concentrate the low level 65Zn even if specific activity of 65Zn was very low in the environmental seawater. Results of radioactive trace experiments showed that the absorption of 134Cs and 65Zn by Perna Viridis was selective

  7. Pharmacokinetics, bioavailability, tissue distribution, excretion, and metabolite identification of methoxyflavones in Kaempferia parviflora extract in rats.

    Mekjaruskul, Catheleeya; Jay, Michael; Sripanidkulchai, Bungorn

    2012-12-01

    Kaempferia parviflora (KP) is an herbal plant in the family of Zingiberaceae. KP mainly contains methoxyflavones, especially 5,7-dimethoxyflavone (DMF), 5,7,4'-trimethoxyflavone (TMF), and 3,5,7,3',4'-pentamethoxyflavone (PMF). The present study was designed to characterize the pharmacokinetics, including bioavailability, distribution, excretion, and identification of metabolites after administration of a KP ethanolic extract. Male rats were orally or intravenously administered a 250 mg/kg concentration of a KP extract, and blood samples were obtained at selected times to determine pharmacokinetic parameters of PMF, TMF, and DMF. For distribution and excretion studies, the organs, urine, and feces samples were collected at various times after oral administration of a larger (750 mg/kg) dose of KP extract. Methoxyflavones in the biological samples were quantified by high-performance liquid chromatography-UV, and the metabolites in urine and feces were further identified by using liquid chromatography-tandem mass spectrometry. After oral administration, concentrations of the three methoxyflavones quickly approached their maximal concentration, ranging from 0.55 to 0.88 μg/ml within 1 to 2 h after administration, and then were gradually excreted with half-lives of 3 to 6 h. The methoxyflavones showed low oral bioavailability of 1 to 4%. Three methoxyflavones were detected at their highest levels in liver followed by kidney. They were also found in lung, testes, and brain. After absorption, organ distribution, and metabolism, the components of KP were mainly eliminated through urine in the forms of demethylated, sulfated, and glucuronidated products and as demethylated metabolites in the feces. The parent compounds were found to have 0.79, 1.76, and 3.10% dose recovery in urine and 1.06, 1.77, and 0.96% dose recovery in feces for PMF, TMF, and DMF, respectively. These studies are the first to describe the pharmacokinetics of KP extract to provide the information on

  8. Absorption, metabolism and excretion of flavanones from single portions of orange fruit and juice and effects of anthropometric variables and contraceptive pill use on flavanone excretion

    Brett, Gary M.; Hollands, Wendy; Needs, Paul W.; Teucher, Birgit; Dainty, Jack R.; Davis, Barry D.; Brodbelt, Jennifer S.; Kroon, Paul A.

    2012-01-01

    Oranges are rich sources of flavonoids that are bioactive and may protect against age-related diseases. The absorption of orange flavanones may be affected by factors such as processing and subject anthropometric variables, and the bioactivity of the absorbed phytochemicals depends on how they are metabolised during absorption. In a randomised cross-over study, twenty subjects consumed a single portion of orange fruit (150 g) or juice (300 g) that contained the flavanones narirutin and hesperidin, and an additional 109 subjects across a broad age range (18–80 years) consumed the juice. Flavanone metabolites were measured in regularly collected samples of plasma and urine. After consumption of fruit or juice, flavanone conjugates, but not the aglycones, were detected in plasma and urine. The flavanone conjugates were shown to include the 7- and 4′-O-monoglucuronides of naringenin, the 7- and 3′-O-monoglucuronides of hesperetin, two hesperetin diglucuronides and a hesperetin sulfo-glucuronide, but no aglycones or rutinosides. Analysis of the plasma pharmacokinetic and urinary excretion data on a dose-adjusted basis indicated no difference in absorption or excretion of either flavanone between the fruit and juice matrices. In the extended urinary excretion dataset the individual variation was very large (range 0–59 % urinary yield). There was a small but significant (P<0·05) decrease in the excretion of hesperetin (but not naringenin) with increasing age (P<0·05), but the effects of sex, BMI and contraceptive pill use were shown not to be associated with the variation in flavanone excretion. PMID:18710603

  9. Distribution, excretion, and metabolism of butylbenzyl phthalate in the rat

    The disposition of butylbenzyl phthalate (BBP), a widely used plasticizer, was evaluated after oral and iv administration to rats. Male Fischer-344 rats were dosed with [14C]BBP at 2, 20, 200, or 2000 mg/kg po or 20 mg/kg iv to determine the effects of dose on rates and routes of excretion. In 24 h, 61-74% of the dose was excreted in the urine and 13-19% in the feces at 2-200 mg/kg. At the 2000-mg/kg dose, 16% of the 14C was excreted in the urine and 57% in the feces. Urinary 14C was composed of monophthalate derivatives (MP: 10-42% of the dose) and glucuronides of these monophthalate derivatives (2-21% of the dose). At 4 h after iv administration of BBP (20 mg/kg), 53-58% of the dose was excreted in the bile of anesthetized rats. No parent compound was found in the bile, but monobutyl phthalate-glucuronide and monobenzyl phthalate-glucuronide (26% and 13% of the dose, respectively) and trace amounts of free monoesters (2% of the dose) and unidentified metabolites (14% of the dose) were present. Although BBP is an asymmetric diester with the potential of forming equal amounts of monbutyl phthalate (MBuP) and monobenzyl phthalate (MBeP), larger quantities of MBuP were formed (MBuP = 44% versus MBeP = 16% of the dose). The half-lives of BBP, MP, and total 14C in blood (20 mg/kg, iv) were 10 min, 5.9 h, and 6.3 h, respectively. This study indicates that BBP is rapidly metabolized and that the major route of excretion of metabolites is biliary. These metabolites are reabsorbed and ultimately eliminated in the urine

  10. Absorption, conjugation and excretion of the flavanones, naringenin and hesperetin from alpha-rhamnosidase-treated orange juice in human subjects

    Bredsdorff, Lea; Nielsen, I.L.F.; Rasmussen, S.E.;

    2010-01-01

    We have determined the absorption, conjugation and excretion of naringenin-7-O-rutinosicle (narirutin) compared to the corresponding glucoside in an orange juice matrix in human subjects. Healthy volunteers (eight men and eight women), in a double blind, randomised, crossover study, consumed orange......-rhamnosidase-treated orange juice was increased about 4-fold (P...

  11. Determination of iron absorption and excretion by whole-body counting; Determination de l'absorption et de l'excretion du fer par la methode de comptage global humain

    Hollard, D.; Benabid, Y.; Berard, M.; Bonnin, J.; Darnault, J.; Millet, M. [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1969-07-01

    Using a whole-body counter, the authors have studied {sup 59}Fe absorption and loss in 8 normal subjects and in 30 iron deficient patients. Results showed that whole-body counting provided an excellent and simple method for iron retention measurements, obviating many inaccuracies of previous technic. Normal absorption of radio iron with this procedure has ranged from 9 per cent to 20 per cent of the administered tracer in normal subjects, with a mean of 15 per cent. A significant increase in {sup 59}Fe absorption was noted in 21 iron-deficient patients in whom the retention ranged from 40 to 100 per cent. However, 3 iron-deficient patients were found to have low absorption, and their severe iron deficiency could be correlated with this defect in absorption. This method permits also the determination of the rate of iron excretion during the following months and therefore the study of the mechanism of some pathological loss. (authors) [French] L'utilisation de la methode de comptage humain global a permis aux auteurs d'etudier l'absorption et l'excretion du fer-59 chez 8 sujets temoins et 30 sujets hyposideremiques. Les resultats montrent que cette technique simple et directe offre de nombreux avantages sur les methodes employees jusqu'a maintenant pour cette determination. La valeur normale de l'absorption du fer chez les temoins est d'environ 15 pour cent de la dose ingeree. Ce chiffre est tres fortement augmente chez 21 sujets hyposideremiques, pouvant atteindre 100 pour cent de la dose ingeree. Par contre, pour 3 malades, cette absorption est si faible qu'elle suggere une carence par defaut d'absorption. Cette methode permet egalement de suivre l'excretion du fer au cours des mois qui suivent l'examen et de determiner le mecanisme de fuites anormales. (auteurs)

  12. Tissue distribution and excretion of 125I-lidamycin in mice and rats

    You-Ping Liu; Quan-Sheng Li; Yu-Rong Huang; Chang-Xiao Liu

    2005-01-01

    AIM: To investigate the tissue distribution, urinary and fecal excretions of 125I-lidamycin (125I-C-1027) in mice and its biliary excretion in rats.METHODS: The total radioactivity assay (RA method) and the radioactivity assay after precipitation with 200 mL/L trichloroacetic acid (TCA-RA method) were used to dete-rmine the tissue distribution, and the urinary and fecal excretions of 125I-C-1027 in mice and its biliary excretion in rats.RESULTS: Tissue concentrations reached the peak at the fifth minute after administration of 125I-C-1027 to mice. The highest concentration was in kidney, and the lowest in brain at all test-time points. The organs of the concentrations of 125I-C-1027 from high to low were kidney, lung, liver, stomach, spleen, uterus, ovary, intestine, muscle, heart, testis, fat, and brain in mice. The accumulative excretionamounts of 0-24 h, and 0-96 h after administration of125I-C-1027 were 68.36 and 71.64% in urine, and 2.60 and 3.21% in feces of mice, respectively, and the accumulative excretion amount of 0-24 h was 3.57% in bile in rats.CONCLUSION: Our results reflect the characteristics of the tissue distribution, urinary and fecal excretions of 125IC-1027 in mice and the biliary excretion of 125I-C-1027and its metabolites in rats, and indicate that 125I-C-1027and its metabolites are mainly distributed in kidney, and excreted in urine.

  13. Actual problems of the distribution of radioisotopes and the kinetics of their excretion

    The paper deals with the character of the distribution of radioisotopes (Cs, Rb, Sr, Ca, Ba, Ra, Ce, La, Pm, Sb, Te, Pu, Y, Zr, Ru, Nb, Po), depending on the way and rhythm of their administration, the physiological state of the organism and physico-chemical factors. It was shown that 10 to 18% of some radioisotopes (Cs137, Nb95, Zr95, Y91, Ru106, and Ce144) were retained in the lungs when administered by inhalation. Caesium and especially strontium are absorbed from the lungs extremely rapidly, while the absorption of ruthenium, cerium and particularly plutonium is slow. The type of distribution of radioactive isotopes does not depend on the species of the animal, as is sometimes the case with the kinetics of their elimination. The rate of Ce144 removal from canine and feline liver is exceedingly low, unlike that in rats, m ice, guinea pigs and rabbits. The amount of the deposited material and the kinetics of its elimination in case of Sr90 and Pu239 are determined by the rhythm and duration of the isotope intake. From the data presented it can be seen that the results of experiments with a single injection do not always characterize the kinetics of the accumulation of the isotope in cases of its continuous administration. Chelate compounds (EDTA, hexametaphosphate - HMP), isotope and non-isotope carriers, and the pH of the original solution change the distribution of hydrolysed elements (cerium, yttrium) and do not affect the type of distribution of elements that are highly-soluble in water. When the pH of the original solution increases, the amount of cerium and yttrium deposition also increases in the organs containing much reticuloendothelial elements (liver, spleen) and decreases in the skeleton and kidneys. The acceleration of the Ce144 and Y91 excretion caused by the chelate compounds (EDTA, HMP) is delayed with the increase of the pH of the original solution. (author)

  14. Effect of natural zeolite on radiocesium excretion and distribution in rats

    The effect was studied of the addition of natural zeolite (clinoptilolite) to food on 134Cs excretion and distribution following oral internal contamination of laboratory rats. With the diet containing 2.5, 5 and 10% zeolite, 134Cs excretion in feces increased while retention of the radionuclide dropped in the liver, kidneys, spleen and the femoral muscle. The decontamination effect was observed of preventive administration of zeolite and of the administration of the sorbent 24 hours after a single internal contamination. (author). 5 figs., 2 tabs., 12 refs

  15. Comparative effects of three dithiocarbamates on tissue distribution and excretion of cadmium in mice

    The effects of sodium N-benzyl-D-glucamine dithiocarbamate (BGD), sodium N-p-hydroxymethylbenzyl-D-glucamine dithiocarbamate (HBGD), and sodium N-p-carboxybenzyl-D-glucamine dithiocarbamate (CBGD), which were newly synthesized, on the distribution and excretion of cadmium were compared in mice exposed to cadmium. Mice were injected with 109CdCl2 (1 mg Cd/kg and 74 KBq of 109Cd/one animal) and 30 min or 24 h later, they were injected with the dithiocarbamates (400 mumols/kg). At 30 min after treatment with cadmium, these chelating agents significantly enhanced the biliary excretion of cadmium, and HBGD and CBGD significantly increased the urinary excretion of the metal. At 24 h after cadmium injection, BGD and HBGD significantly increased the biliary excretion of cadmium and HBGD was the most effective on the biliary excretion of the metal. These chelating agents were effective in mobilizing cadmium from the liver and kidney at 30 min after cadmium treatment. HBGD showed the largest effectiveness on the depression of cadmium contents in the liver and kidney. At 24 h after cadmium treatment, only HBGD among these chelating agents significantly reduced the cadmium contents in the liver and kidney. These results show that the injection of HBGD at both 30 min and 24 h after cadmium treatment can much more effectively mobilize cadmium from the body mainly through the bile without redistribution of cadmium to other tissues, such as brain, testes, and heart, than injection of BGD and CBGD

  16. Influence of food tannins on certain aspects of iron metabolism : Part 1 -- Absorption and excretion in normal and anemic rats

    Studies on absorption and excretion of iron by isotopic and non-isotopic methods in normal and hemolytic anemic rats indicate that dietary food tannins at a dose of 0.5 mg/kg body wt/day tend to increase iron excretion in normal rats but more iron is absorbed or retained in tannin-fed anemic rats and absorption of iron is comparable to that in normal control. Both in vivo and in vitro tannin at a high dose (2.0 mg/kg body wt/day) inhibits the iron absorption in experimental animals. The interference of food tannins (0.5 kg/mg body wt/day) with absorption of iron (59Fe) varies with plant species from which tannin has been prepared. Normal iron balance in tannin-fed (0.5 mg/kg body wt/day) anemic rats may result from increased assimilation of tannin-bound iron in intestinal mucosa, and absorbed tannin appears to remove unabsorbed iron. (auth.)

  17. Relationship between concentration and exposed area on absorption and excretion of T-2 mycotoxin through rabbit skin

    T-2 mycotoxin is a severe skin irritant that can be lethal via the dermal route. A non-occlusive barrier model was developed to study the effects of concentration and size of the exposed area on the absorption rate of toxin in rabbit skin. The skin was shaved and, twenty-four hours later, varying concentrations of both [4H]-labeled and unlabeled T0 toxin in DMSO were painted on the surface. A barrier, consisting of a mesh-jacketed, half-inch foam pad with a hole in the center, was applied to the skin. In order to assess absorption, lethality and excretion were used as endpoints, and dosage, area, and concentration (μ g/cm2) were varied. At doses of 5, 10, and 15 mg/kg of T-2 toxin in DMSO applied to a 200 cm2 area, lethality was 0 of 2, 6 of 11, and 6 of 6 rabbits, respectively. This suggests a direct dose-response relationship. However, at a dose of 10 mg/kg applied in a 100 cm2 area, there were no deaths in 4 rabbits. This indicates a lower rate of absorption at this higher concentration. The percentage of [3H]-toxin excreted was higher at lower doses of T-2 toxin and reduced at higher concentrations. The authors conclude that area, dose, and concentration of applied toxin can influence the amount of T-2 toxin that is absorbed through the skin

  18. Effect of Hibiscus sabdariffa L. Dried Calyx Ethanol Extract on Fat Absorption-Excretion, and Body Weight Implication in Rats

    Carvajal-Zarrabal, O.; Hayward-Jones, P. M.; Z. Orta-Flores; C. Nolasco-Hipólito; Barradas-Dermitz, D. M.; Aguilar-Uscanga, M. G.; Pedroza-Hernández, M. F.

    2009-01-01

    The effect of Hibiscus sabdariffa L. (Hs) calyx extract on fat absorption-excretion and body weight in rats, was investigated. Rats were fed with either a basal diet (SDC = Control diet) or the same diet supplemented with Hs extracts at 5%, 10% and 15% (SD5, SD10 and SD15). Only SD5 did not show significant increases in weight, food consumption and efficiency compared to SDC. The opposite occurred in SD15 group which showed a significant decrease for these three parameters. The SD10 responses...

  19. Excretion, distribution and metabolism of 1,2,4-trichlorobenzene in rats

    1,2,4-Trichlorobenzene (TCB) labeled with C-14 was given perorally to rats at a dosage of 50 mg/kg for excretion and distribution studies. About 66% and 17% of the oral dose was excreted in the urine and feces, respectively, within 7 days. Trapped radioactivity in the expired air amounted to 2.1% of the dose, but production of labeled carbon dioxide was negligible. Tissue residues were evenly distributed throughout the organs and tissues examined, except for the adipose tissue which consistently had a little higher concentration. The urinary, fecal and expiratory metabolites were identified. Free 2,4,5- and 2,3,5-trichlorophenol (TCP) and their conjugates were mainly detected in the urine. 5- or 6-sulfhydryl, methylthio, methylsulfoxide and methylsulfone derivatives of TCB were also detected as minor metabolites. Dichlorobenzenes and unchanged TCB were confirmed in the expired air. Reductive dechlorination seems to be catalysed by intestinal microflora enzymes. (orig.)

  20. Tissue distribution and excretion kinetics of orally administered silica nanoparticles in rats

    Lee JA

    2014-12-01

    Full Text Available Jeong-A Lee,1 Mi-Kyung Kim,1 Hee-Jeong Paek,1 Yu-Ri Kim,2 Meyoung-Kon Kim,2 Jong-Kwon Lee,3 Jayoung Jeong,3 Soo-Jin Choi1 1Department of Food Science and Technology, Seoul Women’s University, Seoul, Republic of Korea; 2Department of Biochemistry and Molecular Biology, Korea University Medical School and College, Seoul, Republic of Korea; 3Toxicological Research Division, National Institute of Food and Drug Safety Evaluation, Chungchungbuk–do, Republic of Korea Purpose: The effects of particle size on the tissue distribution and excretion kinetics of silica nanoparticles and their biological fates were investigated following a single oral administration to male and female rats. Methods: Silica nanoparticles of two different sizes (20 nm and 100 nm were orally administered to male and female rats, respectively. Tissue distribution kinetics, excretion profiles, and fates in tissues were analyzed using elemental analysis and transmission electron microscopy. Results: The differently sized silica nanoparticles mainly distributed to kidneys and liver for 3 days post-administration and, to some extent, to lungs and spleen for 2 days post-administration, regardless of particle size or sex. Transmission electron microscopy and energy dispersive spectroscopy studies in tissues demonstrated almost intact particles in liver, but partially decomposed particles with an irregular morphology were found in kidneys, especially in rats that had been administered 20 nm nanoparticles. Size-dependent excretion kinetics were apparent and the smaller 20 nm particles were found to be more rapidly eliminated than the larger 100 nm particles. Elimination profiles showed 7%–8% of silica nanoparticles were excreted via urine, but most nanoparticles were excreted via feces, regardless of particle size or sex. Conclusion: The kidneys, liver, lungs, and spleen were found to be the target organs of orally-administered silica nanoparticles in rats, and this organ

  1. Three-week psyllium-husk supplementation: effect on plasma cholesterol concentrations, fecal steroid excretion, and carbohydrate absorption in men.

    Abraham, Z D; Mehta, T

    1988-01-01

    This study was conducted to determine the effect of psyllium husk on plasma total and lipoprotein cholesterol in healthy human subjects and to elucidate possible hypocholesterolemic mechanisms. Seven males were given a nutritionally controlled diet based on their usual intake for x = 3 wk followed by 3 wk in which 21 g/d per person psyllium husk was added to the basal diet. After 10 d and after 3 wk of psyllium supplementation, total, low-density, and high-density cholesterol were reduced (p less than 0.002, p less than 0.01, and p less than 0.03, respectively). Fecal steroid excretion, determined from 5-d collections, was not affected by psyllium supplementation. Although psyllium tended to delay lipid absorption, plasma triglycerides, retinyl esters, glucose, insulin, and glucagon quantitated during meal tolerance tests given on the last day of each diet period were not different (p greater than 0.05). Thus the cholesterol-lowering mechanism of psyllium may not involve increased bile acid excretion or decreases in nutrient absorption. PMID:2827455

  2. Distribution and excretion of arsenic in cynomolgus monkey following repeated administration of diphenylarsinic acid

    Kobayashi, Yayoi [National Institute for Environmental Studies, Environmental Health Sciences Division, Tsukuba, Ibaraki (Japan); Negishi, Takayuki [Aoyama Gakuin University, Department of Chemistry and Biological Science, Tokyo (Japan); Mizumura, Ayano; Watanabe, Takayuki [Chiba University, Graduate School of Pharmaceutical Sciences, Chiba (Japan); Hirano, Seishiro [Chiba University, Graduate School of Pharmaceutical Sciences, Chiba (Japan); National Institute for Environmental Studies, Research Center for Environmental Risk, Tsukuba, Ibaraki (Japan)

    2008-08-15

    Diphenylarsinic acid (DPAA), a possible product of degradation of arsenic-containing chemical weapons, was detected in well water in Kamisu City, Ibaraki Prefecture, Japan, in 2003. Although some individuals in this area have been affected by drinking DPAA-containing water, toxicological findings on DPAA are limited. To elucidate the mechanism of its toxicity, it is necessary to determine the metabolic behavior of DPAA in the body. In this study, pregnant cynomolgus monkeys at the 50th day of pregnancy were used. The monkeys were treated daily with 1.0 mg DPAA/kg body weight using a nasogastric tube, and the distribution and excretion of arsenic were examined after the repeated administration and 198-237 days after the last administration of DPAA. Fecal excretion was higher than urinary excretion (ca. 3:2 ratio), and arsenic accumulated in the hair and erythrocytes. Distribution of DAPP to plasma and hemolyzed erythrocytes was also examined by high-performance liquid chromatography-inductively coupled argon plasma mass spectrometry (HPLC-ICP MS). Two peaks were found in the elution profile of arsenic, due to free and probably protein-bound DPAA. The protein-bound arsenic compounds were presumably trivalent diphenylarsenic compounds, since free DPAA was recovered after treatment of heat-denatured samples with hydrogen peroxide. (orig.)

  3. Absorption, metabolism and excretion of diethylene glycol (DEG) in rat and dog

    DEG is a major industrial chemical with considerable consumer exposure. Ingestion of DEG by children and dogs is a common occurrence. DEG metabolism has been reported to proceed with the cleavage of the ether bond, forming oxalic acid and other two-carbon products. DEG toxicity is attributed to the effect of oxalic acid on the kidneys. In the present work the fate of [14C]DEG was studied in rats following iv, oral and dermal administration, and in dogs following oral administration. Dermal doses were poorly (10%) absorbed in 72 h of exposure, but oral doses were well absorbed (ca. 80%) and excreted within 24 h. In each case absorbed DEG was excreted unchanged (>50%) and as a single metabolite (10-30%). The metabolite was isolated and characterized by 13C-NMR and by chemical synthesis as 2-(hydroxy)ethoxyacetic acid. Neither oxalic acid nor other two-carbon metabolites were detected. There was no persistence of DEG or its metabolites in kidney or other organs examined. It is speculated that previous studies of the metabolism and toxicity of DEG have been confounded by the presence of ethylene glycol, which is metabolized to oxalic acid to account for much of the toxicity of commercial grades of DEG

  4. Biliary cholesterol excretion: A novel mechanism that regulates dietary cholesterol absorption

    Sehayek, Ephraim; Ono, Jennie G.; Shefer, Sarah; Nguyen, Lien B.; Wang, Nan; Batta, Ashok K.; Salen, Gerald; Smith, Jonathan D.; Tall, Alan R.; Breslow, Jan L.

    1998-01-01

    The regulation of dietary cholesterol absorption was examined in C57BL/6 and transgenic mice with liver overexpression of the scavenger receptor BI (SR-BI Tg). In C57BL/6 animals, feeding 0.02 to 1% (wt/wt) dietary cholesterol resulted in a dose-dependent decrease in the percentage of dietary cholesterol absorbed. A plot of total daily mass of dietary cholesterol absorbed versus the percentage by weight of cholesterol in the diet yielded a curve suggesting a saturable process with a Km of 0.4...

  5. Evaluating the enantioselective distribution, degradation and excretion of epoxiconazole in mice following a single oral gavage.

    Wang, Dezhen; Qiu, Jing; Zhu, Wentao; Zhang, Ping; Deng, Nian; Wang, Xinru; Wang, Yao; Zhou, Zhiqiang

    2015-01-01

    1. The enantiomeric enrichment or degradation of epoxiconazole has been reported in grape, soil, tubifex and mealworm beetle. But, little is known about its enantioselective behaviors in mammals. 2. To further understand differences in the distribution, degradation and excretion of epoxiconazole enantiomers in vivo, male CD-1 mice were selected as the test model to investigate the enantioselective behaviors after a single oral gavage. Mice were sacrificed after 1 h, 3 h, 7 h, 12 h, 24 h, 48 h, 72 h treatment, blood, tissues and excretions were collected for epoxiconazole analysis by LC-MS/MS. 3. On the Lux-Cellulose-1 chiral column, an enrichment of the second eluting (+)-epoxiconazole was generally observed, and feces and urine showed similar EF with major tissues. 4. To elucidate the potential role of intestinal bacterial flora in stereospecific degradation of epoxiconazole, mice fecal flora were cultured in vitro and incubated with epoxiconazole for 48 h. Results showed that (-)-epoxiconazole was preferentially degraded by intestinal bacterial. 5. These results may provide useful information for risk assessment of epoxiconazole on non-target animals. PMID:26108358

  6. Pharmacokinetics, distribution, metabolism, and excretion of the dual reuptake inhibitor [(14)C]-nefopam in rats.

    Yu, Jian; Solon, Eric; Shen, Helen; Modi, Nishit B; Mittur, Aravind

    2016-11-01

    1. This study examined the pharmacokinetics, distribution, metabolism, and excretion of [(14)C] nefopam in rats after a single oral administration. Blood, plasma, and excreta were analyzed for total radioactivity, nefopam, and metabolites. Metabolites were profiled and identified. Radioactivity distribution was determined by quantitative whole-body autoradiography. 2. The pharmacokinetic profiles of total radioactivity and nefopam were similar in male and female rats. Radioactivity partitioned approximately equally between plasma and red blood cells. A majority of the radioactivity was excreted in urine within 24 hours and mass balance was achieved within 7 days. 3. Intact nefopam was a minor component in plasma and excreta. Numerous metabolites were identified in plasma and urine generated by multiple pathways including: hydroxylation/oxidation metabolites (M11, M22a and M22b, M16, M20), some of which were further glucuronidated (M6a to M6c, M7a to M7c, M8a and M8b, M3a to M3d); N-demethylation of nefopam to metabolite M21, which additionally undergoes single or multiple hydroxylations or sulfation (M9, M14, M23), with some of the hydroxylated metabolites further glucuronidated (M2a to M2d). 4. Total radioactivity rapidly distributed with highest concentrations found in the urinary bladder, stomach, liver, kidney medulla, small intestine, uveal tract, and kidney cortex without significant accumulation or persistence. Radioactivity reversibly associated with melanin-containing tissues. PMID:26927982

  7. 54Mn absorption and excretion in rats fed soy protein and casein diets

    Rats were fed diets containing either soy protein or casein and different levels of manganese, methionine, phytic acid, or arginine for 7 days and then fed test meals labeled with 2 microCi of 54Mn after an overnight fast. Retention of 54Mn in each rat was measured every other day for 21 days using a whole-body counter. Liver manganese was higher (P less than 0.0001) in soy protein-fed rats (8.8 micrograms/g) than in casein-fed rats (5.2 micrograms/g); manganese superoxide dismutase activity also was higher in soy protein-fed rats than in casein-fed rats (P less than 0.01). There was a significant interaction between manganese and protein which affected manganese absorption and biologic half-life of 54Mn. In a second experiment, rats fed soy protein-test meals retained more 54Mn (P less than 0.001) than casein-fed rats. Liver manganese (8.3 micrograms/g) in the soy protein group was also higher than that (5.7 micrograms/g) in the casein group (P less than 0.0001), but manganese superoxide dismutase activity was unaffected by protein. Supplementation with methionine increased 54Mn retention from both soy and casein diets (P less than 0.06); activity of manganese superoxide dismutase increased (P less than 0.05) but liver manganese did not change. The addition of arginine to casein diets had little effect on manganese bioavailability. Phytic acid affected neither manganese absorption nor biologic half-life in two experiments, but it depressed liver manganese in one experiment. These results suggest that neither arginine nor phytic acid was the component in soy protein which made manganese more available from soy protein diets than casein diets

  8. Characteristics of pharmacokinetics, distribution and excretion of recombinant human interleukin-3 in mice

    Concentration-time profiles of 125I-labelled recombinant human interleukin-3 (125I-rhIL-3) were determined by reverse phase high performance liquid chromatography (RHPLC) after subcutaneous administration of the drug 90 μg/kg in mice. The elimination T1/2 in plasma was 1.73 h. Rapid biodegradation was found in plasma. The distribution profiles of total radioactivity were as follows: The highest level was found in urinary system. Levels in bile-enteric system, lymph nodes, bone marrow and spleen approximated that in plasma, and level in brain was the lowest. A total of (84.0 +- 9.2)% of the injected dose was excreted through urine and feces within 48 h, of which (71.9 +- 6.7)% through urine and (12.2 +- 5.3)% through feces. The RHPLC analysis revealed that kidney was one of the major organ for biodegradation

  9. Absorption Measure Distribution in Mrk 509

    Adhikari, T. P.; Różańska, A.; Sobolewska, M.; Czerny, B.

    2015-12-01

    In this paper we model the observed absorption measure distribution (AMD) in Mrk 509, which spans three orders of magnitude in ionization level with a single-zone absorber in pressure equilibrium. AMD is usually constructed from observations of narrow absorption lines in radio-quiet active galaxies with warm absorbers. We study the properties of the warm absorber in Mrk 509 using recently published broadband spectral energy distribution observed with different instruments. This spectrum is an input in radiative transfer computations with full photoionization treatment using the titan code. We show that the simplest way to fully reproduce the shape of AMD is to assume that the warm absorber is a single zone under constant total pressure. With this assumption, we found theoretical AMD that matches the observed AMD determined on the basis of the 600 ks reflection grating spectrometer XMM-Newton spectrum of Mrk 509. The softness of the source spectrum and the important role of the free-free emission breaks the usual degeneracy in the ionization state calculations, and the explicit dependence of the depths of AMD dips on density open a new path to the density diagnostic for the warm absorber. In Mrk 509, the implied density is of the order of 108 cm-3.

  10. Nickel Dermatitis - Nickel Excretion

    Menné, T.; Thorboe, A.

    1976-01-01

    Nickel excretion in urine in four females -sensitive to nickel with an intermittent dyshidrotic eruption was measured with flameless atomic absorption. Excretion of nickel was found to be increased in association with outbreaks of vesicles. The results support the idea that the chronic condition ...

  11. Tissue Distribution, Excretion and Pharmacokinetics of the Environmental Pollutant Dibenzo[def,p]chrysene in Mice.

    Sun, Yuan-Wan; El-Bayoumy, Karam; Aliaga, Cesar; Awad, Alaa S; Gowda, Krishne; Amin, Shantu; Chen, Kun-Ming

    2015-07-20

    Dibenzo[def,p]chrysene (DBP), a representative example of the class of polycyclic aromatic hydrocarbon (PAH), is known to induce tumors in multiple organ sites including the ovary, lung, mammary glands, and oral cavity in rodents. The goal of this study was to test the hypothesis that the levels of DBP and its metabolites that reach and retain the levels for an extended time in the target organs as well as the capacity of these organs to metabolize this carcinogen to active metabolites that can damage DNA may account for its tissue selective tumorigenicity. Therefore, we used the radiolabeled [(3)H] DBP to accurately assess the tissue distribution, excretion, and pharmacokinetics of this carcinogen. We also compared the levels of DBPDE-DNA adducts in a select target organ (ovary) and nontarget organs (kidney and liver) in mice treated orally with DBP. Our results showed that after 1 week, 91.40 ± 7.23% of the radioactivity was recovered in the feces; the corresponding value excreted in the urine was less than 2% after 1 week. After 24 h, the stomach had the highest radioactivity followed by the intestine and the liver; however, after 1 week, levels of the radioactivity in these organs were the lowest among tissues examined including the ovary and liver; the pharmacokinetic analysis of DBP was conducted using a one compartment open model. The level of (-)-anti-trans-DBPDE-dA in the ovaries (8.91 ± 0.08 adducts/10(7) dA) was significantly higher (p < 0.01) than the levels of adducts in kidneys (0.69 ± 0.09 adducts/10(7) dA) and livers (0.63 ± 0.11 adducts/10(7) dA). Collectively, the results of the tissue distribution and pharmacokinetic analysis may not fully support our hypothesis, but the capacity of the target organs vs nontarget organs to metabolize DBP to active intermediates that can damage DNA may account for its tissue selective tumorigenicity. PMID:26034881

  12. Quantitative analysis of absorption, metabolism, and excretion of benzoxazinoids in humans after the consumption of high- and low-benzoxazinoid diets with similar contents of cereal dietary fibres: a crossover study

    Jensen, Bettina M.; B. Adhikari, Khem; Schnoor, Heidi J.;

    2016-01-01

    PURPOSE: Benzoxazinoids (BXs) are a group of wholegrain phytochemicals with potential pharmacological properties; however, limited information exists on their absorption, metabolism, and excretion in humans. The aim of this study was to investigate the dose-dependent uptake and excretion of dietary...

  13. Studies on the relationship between cotton aphids feedding, excretion, absorption and ability of cotton varieties resisting aphids using radioactive tracer 14C

    The experments were conducted in 1980-1982. The aphids were placed on the plants after the cotton plants were exposed to 14CO2 under the sunlight for 1 hr. and then coverd with paper covering in the special photosynthesis chambers. The honey dew excreted by aphids was collected on the paper covering. Then the aphids and the paper coverings both put into scintillation liquid, and the radioactivity was determined. The results indicated that the aphids being different instars had different approximate rate of 14C absorption. 71.2% of total absorption was excreted in the form of honey dew; 28.8% of total absorption was taken by the aphid bodies (included milts) in the nymph stage, while 23.5% of total absorption was uptaken in the adult stage. The aphids feeding on the aphid-resistant cotton varieties (such as 'Junhai 1', 'Shanghai 605') had 23.5-26.7% approximate absorbing rate, whereas those on the aphid-sensitive cotton varieties (for example 'Uganda 2') had over 28.1% approximate absorbing rate. These results showed no difference from the results of field experiments

  14. Comparative effects of ten dithiocarbamate and thiuram compounds on tissue distribution and excretion of lead in rats.

    Oskarsson, A

    1987-10-01

    Combined treatment of rats with lead and disulfiram is known to cause increased levels of lead in brain and potentiation of the neurotoxicity of lead. Ten dithiocarbamate and thiuram compounds, including disulfiram, were compared for their efficacies in influencing tissue distribution of a trace dose of intravenously injected lead plus 203Pb in rats. The tested compounds were sodium diethyldithiocarbamate (DEDTC), sodium dimethyldithiocarbamate (DMDTC), tetraethylthiuram disulfide (disulfiram), a complex of zinc and manganese ethylenebisdithiocarbamate (mancozeb), manganese ethylenebisdithiocarbamate (maneb), sodium monomethyldithiocarbamate (metham), zinc propylene bisdithiocarbamate (propineb), tetramethylthiuram disulfide (thiram), zinc ethylenebisdithiocarbamate (zineb), and zinc dimethyldithiocarbamate (ziram). Pronounced effects on tissue distribution of lead were seen after peroral and subcutaneous administration of DEDTC, DMDTC, disulfiram, metham, thiram, and ziram. After peroral administration there was an increased uptake of lead in brain, liver, lung, and spleen and a decreased uptake in femur compared to control rats receiving only lead. Thiram was the most effective compound in enhancing lead uptake in brain, causing a 100-fold increase in 203Pb concentration at 72 hr survival. After subcutaneous administration, metham caused the highest increase in brain concentration of 203Pb. Fecal excretion of lead, which is the main excretory pathway, was decreased after peroral administration of disulfiram, ziram, and thiram to about 20% of the excretion in control rats at 48 hr. Urinary excretion of lead was significantly decreased in all the treated groups except the group treated with zineb. The effects on tissue distribution and excretion can be explained by in vivo formation of lipophilic complexes between lead and these compounds or their metabolites facilitating the transport of lead through cell membranes and the blood-brain barrier. Zineb, maneb

  15. Lactobacillus rhamnosus Strain GG Modulates Intestinal Absorption, Fecal Excretion, and Toxicity of Aflatoxin B1 in Rats▿

    Gratz, S.; Täubel, M.; Juvonen, R. O.; Viluksela, M.; Turner, P. C.; Mykkänen, H.; El-Nezami, H.

    2006-01-01

    In this study, the modulation of aflatoxin B1 (AFB1) uptake in rats by administration of the probiotic Lactobacillus rhamnosus GG was demonstrated. Fecal AFB1 excretion in GG-treated rats was increased via bacterial AFB1 binding. Furthermore, AFB1-associated growth faltering and liver injury were alleviated with GG treatment.

  16. Chelation in metal intoxication X: influence of different polyaminocarboxylic acids and thiol chelators in the excretion and tissue distribution of 54Mn in rat

    The influence of some selected polyaminocarboxylic acids and thiol metal binding agents on the urinary and faecal excretions of 54Mn and on the tissue distribution of 54Mn in 54MnC12 administered rats was studied to find a suitable chelating drug for Mn poisoning. HEDTA, CDTA, DTPA and TTHA were highly successful in enhancing the excretion of 54Mn and reducing the tissue levels of 54Mn in rats. The thiol chelators viz. D L-penicillamine, N-acetyl D L-penicillamine and DMS could neither influence the excretion nor the tissue distribution of 54Mn suggesting poor affinity of the metal towards sulfhydryl groups

  17. Physiologically-based pharmacokinetic modelling of distribution, bioaccumulation and excretion of POPs in Greenland sledge dogs (Canis familiaris).

    Sonne, Christian; Gustavson, Kim; Letcher, Robert J; Dietz, Rune

    2015-10-01

    We used PBPK (physiologically-based pharmacokinetic) modelling to investigate distribution, bioaccumulation and excretion of the seven POPs (persistent organic pollutants) CB-99, CB-153, HCB, oxychlordane, p,p'-DDE, BDE-47 and BDE-99 in 4 adult captive Greenland sledge dog (Canis familiaris) bitches fed minke whale (Balaenoptera acuterostrata) blubber for 500-635 days. The PBPK modelled POP concentrations in adipose tissue, liver, kidney and plasma were mostly within a factor 2 of actual measured tissue levels even for those at the lower concentration end. The excretion route for oxychlordane and CB-153 was modelled to be via faeces while lung alveolar excretion dominated for BDE-47, BDE-99, HCB, p,p'-DDE and CB-99. Furthermore the model suggested the retained mass of POPs after 500 and 635 days of exposure, respectively, to be relatively low despite these POPs being highly recalcitrant. The retention increased in the following order (% of total intake); p,p'-DDE (1%)tool in risk assessment of POPs in arctic mammals. PMID:26210746

  18. Human systemic exposure to [¹⁴C]-paraphenylenediamine-containing oxidative hair dyes: Absorption, kinetics, metabolism, excretion and safety assessment.

    Nohynek, Gerhard J; Skare, Julie A; Meuling, Wim J A; Wehmeyer, Kenneth R; de Bie, Albertus Th H J; Vaes, Wouter H J; Dufour, Eric K; Fautz, Rolf; Steiling, Winfried; Bramante, Mario; Toutain, Herve

    2015-07-01

    Systemic exposure was measured in humans after hair dyeing with oxidative hair dyes containing 2.0% (A) or 1.0% (B) [(14)C]-p-phenylenediamine (PPD). Hair was dyed, rinsed, dried, clipped and shaved; blood and urine samples were collected for 48 hours after application. [(14)C] was measured in all materials, rinsing water, hair, plasma, urine and skin strips. Plasma and urine were also analysed by HLPC/MS/MS for PPD and its metabolites (B). Total mean recovery of radioactivity was 94.30% (A) or 96.21% (B). Mean plasma Cmax values were 132.6 or 97.4 ng [(14)C]-PPDeq/mL, mean AUC(0-∞) values 1415 or 966 ng [(14)C]-PPDeq/mL*hr in studies A or B, respectively. Urinary excretion of [(14)C] mainly occurred within 24 hrs after hair colouring with a total excretion of 0.72 or 0.88% of applied radioactivity in studies A or B, respectively. Only N,N'-diacetylated-PPD was detected in plasma and the urine. A TK-based human safety assessment estimated margins of safety of 23.3- or 65-fold relative to respective plasma AUC or Cmax values in rats at the NOAEL of a toxicity study. Overall, hair dyes containing PPD are unlikely to pose a health risk since they are used intermittently and systemic exposure is limited to the detoxified metabolite N,N'-diacetyl-PPD. PMID:25846501

  19. Pharmacokinetics, tissue distribution and excretion of a recombinant fusion protein 125I-rhTNT-IL2

    This study examined the tissues distribution and pharmacokinetics of rhTNT-IL2, a fusion protein, in rats and macaques after iv. injection. The rhTNTIL2 was labeled with 125I. The 125I-rhTNT-IL2 was administered into rats and macaques at a dose of 250 μg x kg-1 and 125 μg x kg-1, respectively. Upon administration, rhTNT-IL2 declined in tri-exponentially with the half-lives of 1.78 h (T1/2α), 25.06 h (T1/2β), 114.19 h (T1/2γ) for rats and 1.87 h (T1/2α), 9.82 h (T1/2β), 43.17 h (T1/2γ) for macaques. The fraction of 125I-rhTNT-IL2 excreted in feces was low (about 1%), while the majority of 125I-rhTN-IL2 was excreted in urine. The tissue distributions showed that the liver, spleen and heart were major organs for deposition of the fusion protein in rats and macaques in 48-hour post-injection, and the fusion protein could not penetrate through blood brain barrier. (author)

  20. A Proteomics Approach to the Study of Absorption, Distribution, Metabolism, Excretion, and Toxicity

    Nordvarg, Helena; Flensburg, John; Rönn, Ola; Öhman, Johan; Marouga, Rita; Lundgren, Bo; Haid, Daniel; Malmport, Eva; Goscinski, Jan; Hörnsten, Lena; Scigelova, Michaela; Bourin, Stephanie; Garberg, Per; Woffendin, Gary; Fenyö, David

    2004-01-01

    A proteomics approach was used to identify liver proteins that displayed altered levels in mice following treatment with a candidate drug. Samples from livers of mice treated with candidate drug or untreated were prepared, quantified, labeled with CyDye DIGE Fluors, and subjected to two-dimensional electrophoresis. Following scanning and imaging of gels from three different isoelectric focusing intervals (3–10, 7–11, 6.2–7.5), automated spot handling was performed on a large number of gel spo...

  1. A proteomics approach to the study of absorption, distribution, metabolism, excretion, and toxicity.

    Nordvarg, Helena; Flensburg, John; Rönn, Ola; Ohman, Johan; Marouga, Rita; Lundgren, Bo; Haid, Daniel; Malmport, Eva; Goscinski, Jan; Hörnsten, Lena; Scigelova, Michaela; Bourin, Stephanie; Garberg, Per; Woffendin, Gary; Fenyö, David; Bergling, Hélène; Forsberg, Erik

    2004-12-01

    A proteomics approach was used to identify liver proteins that displayed altered levels in mice following treatment with a candidate drug. Samples from livers of mice treated with candidate drug or untreated were prepared, quantified, labeled with CyDye DIGE Fluors, and subjected to two-dimensional electrophoresis. Following scanning and imaging of gels from three different isoelectric focusing intervals (3-10, 7-11, 6.2-7.5), automated spot handling was performed on a large number of gel spots including those found to differ more than 20% between the treated and untreated condition. Subsequently, differentially regulated proteins were subjected to a three-step approach of mass spectrometry using (a) matrix-assisted laser desorption/ionization time-of-flight mass spectrometry peptide mass fingerprinting, (b) post-source decay utilizing chemically assisted fragmentation, and (c) liquid chromatography-tandem mass spectrometry. Using this approach we have so far resolved 121 differentially regulated proteins following treatment of mice with the candidate drug and identified 110 of these using mass spectrometry. Such data can potentially give improved molecular insight into the metabolism of drugs as well as the proteins involved in potential toxicity following the treatment. The differentially regulated proteins could be used as targets for metabolic studies or as markers for toxicity. PMID:15585823

  2. Absorption, distribution, metabolism, and excretion of macitentan, a dual endothelin receptor antagonist, in humans.

    Bruderer, Shirin; Hopfgartner, Gérard; Seiberling, Michael; Wank, Janine; Sidharta, Patricia N; Treiber, Alexander; Dingemanse, Jasper

    2012-09-01

    Macitentan is a tissue-targeting, dual endothelin receptor antagonist, currently under phase 3 investigation in pulmonary arterial hypertension. In this study the disposition and metabolism of macitentan were investigated following administration of a single oral 10 mg dose of (14)C-macitentan to six healthy male subjects. The total radioactivity in matrices was determined using liquid scintillation counting. The proposed structure of metabolites was based on mass spectrometry characteristics and, when available, confirmed by comparison with reference compounds. Mean (± SD) cumulative recovery of radioactivity from faeces and urine was 73.6% (± 6.2%) of the administered radioactive dose, with 49.7% (± 3.9%) cumulative recovery from urine, and 23.9% (± 4.8%) from faeces. In plasma, in addition to parent macitentan, ACT-132577, a pharmacologically active metabolite elicited by oxidative depropylation and the carboxylic acid metabolite ACT-373898 were identified. In urine, four entities were identified, with the hydrolysis product of ACT-373898 as the most abundant one. In faeces, five entities were identified, with the hydrolysis product of macitentan and ACT-132577 as the most abundant one. Concentrations of total radioactivity in whole blood were lower compared to plasma, which indicates that macitentan and its metabolites poorly bind to or penetrate into erythrocytes. PMID:22458347

  3. Effect of high-dose growth hormone and glutamine on body composition, urine creatinine excretion, fatty acid absorption, and essential fatty acids status in short bowel patients - A randomized, double-blind, crossover, placebo-controlled study

    Jeppesen, P.B.; Szkudlarek, J.; Høy, Carl-Erik; Mortensen, P.B.

    2001-01-01

    describes changes in body weight (BW) and composition, 24-h urine creatinine excretion, intestinal fatty acid absorption (total, saturated, unsaturated and EFA), and EFA status in relation to treatment with GH+GLN in s short bowel patients. Methods: A double-blind, crossover study between placebo and growth...... with baseline. Twenty-four-hour urine creatinine excretion did not differ between study periods. No changes in intestinal absorption of fatty acids were seen, and no changes in EFAs measured in plasma phospholipids were observed. Only 1 of 8 patients, who did not receive parenteral lipids, had a Holman...... treatment to placebo periods. The increase in LBM measured by DEXA scan, comparing treatment and baseline periods, was not accompanied by an increase in the 24-h urinary creatinine excretion and is suspected to be associated with an accumulation in extracellular fluids....

  4. Tissue distribution and excretion of the five components of Portulaca oleracea L. extract in rat assessed by UHPLC

    Wenjie Zhang

    2015-09-01

    Full Text Available The aim of the present study was to investigate the tissue distribution and excretion of five components of Portulaca oleracea L. extract (POE in rat following oral administration. A rapid, sensitive and specific ultra-high performance liquid chromatography (UHPLC method with puerarin as the internal standard was used for the quantitative analysis of five components of POE, including caffeic acid (CA, p-coumaric acid (p-CA, ferulic acid (FA, quercitrin (QUER and hesperidin (HP in rat tissues including the liver, intestine, stomach, muscle, heart, lung, brain, kidney and spleen, urine and feces. The results show that onlyp-CA and FA were found in nearly all tissues with low cumulative ratios, and CA was higher in the intestine and stomach with a slightly higher cumulative ratio in the urine and feces after 24 h. HP and QUER were found at low levels in the tissues with low cumulative ratios.

  5. Pharmacokinetics, tissue distribution, excretion, and metabolite profiling of PEGylated rFIX (nonacog beta pegol, N9-GP) in rats.

    Sternebring, Ola; Christensen, Jesper Kammersgaard; Bjørnsdottir, Inga

    2016-09-20

    Nonacog beta pegol (N9-GP) is a novel recombinant factor IX conjugated with a 40-kDa branched polyethylene glycol (PEG) to extend plasma half-life (t½) compared with native FIX, developed for the treatment of haemophilia B. This is the first time distribution, metabolism, and excretion data of N9-GP have been presented. ADME studies were performed using single i.v. doses of radiolabelled N9-GP administered to rats, focussing on the biological fate of the 40-kDa PEG. Results indicated that N9-GP-related radioactivity was distributed throughout the body, being most abundant in highly vascularised tissues, and with lowest levels seen in the central nervous system. N9-GP was cleared from plasma within 1week after dosing, while total radioactivity was eliminated more slowly, in a more pronounced biphasic manner. N9-GP seems to be cleared via receptor-mediated uptake (e.g., in the liver) or via the reticuloendothelial system with subsequent proteolysis. PEG is thereafter either cleared alongside the protein or released back into circulation. Furthermore, N9-GP-related radioactivity was excreted in both faeces and urine as 40kDa PEG and degradation products. Some PEG-related radioactivity (not in any particular organ) was present in the carcass 12weeks postdose, consistent with the long terminal elimination t½ of plasma radioactivity. As shown here for N9-GP, and previously for other protein-PEG conjugate products, disposition kinetics of conjugates and individual constituents appears to be compound specific. In addition to the size/structure of the PEG and protein moieties, protein-specific clearance pathways may contribute to the disposition of intact conjugate and PEG moiety. PMID:27378188

  6. Distribution and excretion of boron after intravenous administration of disodium mercaptoundecahydro-closo-dodecaborate to rats

    Disodium mercaptoundecahydro-closo-dodecaborate (BSH) is an important compound for boron neutron capture therapy. The pharmacokinetics of boron by BSH were studied in normal rats after rapid intravenous injection at three doses (30, 100, 300 mg/kg) or continuous infusion (100 mg/kg/ 30 min). The boron concentration in biological samples was measured by inductively coupled plasma atomic emission spectroscopy. The blood half-lives of boron in the elimination phase (t1/2 β) after rapid injection of BSH at doses of 30, 100 and 300 mg/kg were 1.7, 17 and 19 hr, respectively. AUC (32, 219 and 4030 μg·hr/ml) increased with the dose, but there was no proportionality among the values. Total clearance decreased drastically from 233 ml/hr/kg (100 mg/kg) to 38 ml/hr/kg (300 mg/kg). As boron was excreted mainly into urine, these results suggest that renal function failure might occur with dosing of 300 mg/kg. In the case of continuous infusion of 100 mg/kg of BSH for 30 min, the pharmacokinetic parameters were similar to those of rapid injection of 100 mg/kg. The highest boron concentration was observed in the kidney and the lowest in the brain. After multiple dosing of BSH at 100 mg/kg/day x 14 days, the boron concentrations in blood, liver, lung and kidney at 24 hr after the last dosing were higher than those after single dosing and were similar to those of simulated values calculated from the single dosing parameters. These results clearly indicated that boron does not accumulate unexpectedly in any tissue with multiple dosing of 100 mg/kg of BSH for two weeks. (author)

  7. Gills as a glutathione-dependent metabolic barrier in Pacific oysters Crassostrea gigas: Absorption, metabolism and excretion of a model electrophile.

    Trevisan, Rafael; Mello, Danielle F; Delapedra, Gabriel; Silva, Danilo G H; Arl, Miriam; Danielli, Naissa M; Metian, Marc; Almeida, Eduardo A; Dafre, Alcir L

    2016-04-01

    The mercapturic acid pathway (MAP) is a major phase II detoxification route, comprising the conjugation of electrophilic substances to glutathione (GSH) in a reaction catalyzed by glutathione S-transferase (GST) enzymes. In mammals, GSH-conjugates are exported from cells, and the GSH-constituent amino acids (Glu/Gly) are subsequently removed by ectopeptidases. The resulting Cys-conjugates are reabsorbed and, finally, a mercapturic acid is generated through N-acetylation. This pathway, though very well characterized in mammals, is poorly studied in non-mammalian biological models, such as bivalve mollusks, which are key organisms in aquatic ecosystems, aquaculture activities and environmental studies. In the present work, the compound 1-chloro-2,4-dinitrobenzene (CDNB) was used as a model electrophile to study the MAP in Pacific oysters Crassostrea gigas. Animals were exposed to 10μM CDNB and MAP metabolites were followed over 24h in the seawater and in oyster tissues (gills, digestive gland and hemolymph). A rapid decay was detected for CDNB in the seawater (half-life 1.7h), and MAP metabolites peaked in oyster tissues as soon as 15min for the GSH-conjugate, 1h for the Cys-conjugate, and 4h for the final metabolite (mercapturic acid). Biokinetic modeling of the MAP supports the fast CDNB uptake and metabolism, and indicated that while gills are a key organ for absorption, initial biotransformation, and likely metabolite excretion, hemolymph is a possible milieu for metabolite transport along different tissues. CDNB-induced GSH depletion (4h) was followed by increased GST activity (24h) in the gills, but not in the digestive gland. Furthermore, the transcript levels of glutamate-cysteine ligase, coding for the rate limiting enzyme in GSH synthesis, and two phase II biotransformation genes (GSTpi and GSTo), presented a fast (4h) and robust (∼6-70 fold) increase in the gills. Waterborne exposure to electrophilic compounds affected gills, but not digestive gland

  8. The effects of nutritional factors on absorption, retention and excretion of organic and inorganic mercury in mice and rats

    The industrial use of mercury compounds is declining, but naturally occurring mercury always exists. Earlier experiments have demonstrated effects of dietary fibres, high protein diets and dry milk on whole-body retention and relative organ distribution of orally and intraperitoneally administered methylmercy chloride and mercuric chloride were determined in female NMRI/born mice fed semisynthetic diets in which the energy contribution from protein (soy protein, caseinate or fish protein), or from lipids (coconut oil, cod liver oil, or soy oil), was varied or to which different amounts and types of dietary fibres (cellulose, 60% fibre tablet, pectin K, oat, corn and soy fibre) were added. The whole-body retention of both organic and inorganic mercury depended on the diet composition. Thus, highly significant reductions in whole-body retention of mercury were observed in groups of mice orally administered methylmercury chloride and fed diets with cod liver oil as lipid energy source, or diets with high amounts of soy protein or fish protein as protein energy source, compared to groups fed diets with coconut oil, soy oil, caseinate and lower amounts of fish or soy protein. In most cases, the relative organ distribution was not significantly affected by the diet composition, except that the fractional mercury deposition in the brain was increased in the groups receiving high amounts of cod liver oil compared to the group fed high amounts of coconut oil. (au) 112 p

  9. Numerical calculations of the ray trace, absorption distribution and absorption efficiency of the laser beam in spherical symmetric plasmas

    The computer code ''ABS'', which can calculate the absorption rate and distribution of the laser light in spherical symmetric plasmas has been developed. The dependences of the absorption rate and distribution on the focusing position and their wavelength dependences were obtained. It was found that with a shorter wavelength laser light, the absorption nonuniformity on the fusion pellets will be reduced as well as the absorption rate will increase. (author)

  10. Assimilation, excretion and distribution of cobalt-60 in the rat after daily ingestion of contaminated marine food products

    The results of a study of radionuclide kinetics in nine female rats fed with 60Co contaminated rations are reported. It was found that equilibrium between ingestion and excretion of cobalt is very rapidly reached (48 hr at most), fecal excretion predominates over urinary excretion, and the assimilation of cobalt is very slight (0.60%). While muscles account for the greatest percentage mass within the body and kidneys account for only a slight percentage, the greatest concentration of cobalt in the rat is seen in the kidneys; in contrast to other mammals, where the liver remains the organ where primary accumulation of cobalt is observed. (U.K.)

  11. Absorption, Metabolism, and Excretion by Freely Moving Rats of 3,4-DHPEA-EDA and Related Polyphenols from Olive Fruits (Olea europaea

    Shunsuke Kano

    2016-01-01

    Full Text Available Absorption, metabolism, and excretion of 3,4-DHPEA-EDA, oleuropein, and hydroxytyrosol isolated from olive fruits were newly evaluated after oral and intravenous administration in freely moving rats cannulated in the portal vein, jugular vein, and bile duct. Orally administered 3,4-DHPEA-EDA, an important bioactive compound in olive pomace, was readily absorbed and metabolized to hydroxytyrosol, homovanillic acid, and homovanillyl alcohol, as shown by dose-normalized 4 h area under the curve (AUC0→4 h/Dose values of 27.7, 4.5, and 4.2 μM·min·kg/μmol, respectively, in portal plasma after oral administration. The parent compound 3,4-DHPEA-EDA was not observed in the portal plasma, urine, and bile after oral and intravenous administration. Additionally, hydroxytyrosol, homovanillic acid, and homovanillyl alcohol in the portal plasma after oral administration of hydroxytyrosol showed 51.1, 22.8, and 7.1 μM·min·kg/μmol AUC0→4 h/Dose, respectively. When oleuropein, a polar glucoside, was injected orally, oleuropein in the portal plasma showed 0.9 μM·min·kg/μmol AUC0→4 h/Dose. However, homovanillic acid was detected from oleuropein in only a small amount in the portal plasma. Moreover, the bioavailability of hydroxytyrosol and oleuropein for 4 hours was 13.1% and 0.5%, respectively. Because the amount of 3,4-DHPEA-EDA in olive fruits is about 2-3 times greater than that of hydroxytyrosol, the metabolites of 3,4-DHPEA-EDA will influence biological activities.

  12. Absorption, Metabolism, and Excretion by Freely Moving Rats of 3,4-DHPEA-EDA and Related Polyphenols from Olive Fruits (Olea europaea).

    Kano, Shunsuke; Komada, Haruna; Yonekura, Lina; Sato, Akihiko; Nishiwaki, Hisashi; Tamura, Hirotoshi

    2016-01-01

    Absorption, metabolism, and excretion of 3,4-DHPEA-EDA, oleuropein, and hydroxytyrosol isolated from olive fruits were newly evaluated after oral and intravenous administration in freely moving rats cannulated in the portal vein, jugular vein, and bile duct. Orally administered 3,4-DHPEA-EDA, an important bioactive compound in olive pomace, was readily absorbed and metabolized to hydroxytyrosol, homovanillic acid, and homovanillyl alcohol, as shown by dose-normalized 4 h area under the curve (AUC0→4 h/Dose) values of 27.7, 4.5, and 4.2 μM·min·kg/μmol, respectively, in portal plasma after oral administration. The parent compound 3,4-DHPEA-EDA was not observed in the portal plasma, urine, and bile after oral and intravenous administration. Additionally, hydroxytyrosol, homovanillic acid, and homovanillyl alcohol in the portal plasma after oral administration of hydroxytyrosol showed 51.1, 22.8, and 7.1 μM·min·kg/μmol AUC0→4 h/Dose, respectively. When oleuropein, a polar glucoside, was injected orally, oleuropein in the portal plasma showed 0.9 μM·min·kg/μmol AUC0→4 h/Dose. However, homovanillic acid was detected from oleuropein in only a small amount in the portal plasma. Moreover, the bioavailability of hydroxytyrosol and oleuropein for 4 hours was 13.1% and 0.5%, respectively. Because the amount of 3,4-DHPEA-EDA in olive fruits is about 2-3 times greater than that of hydroxytyrosol, the metabolites of 3,4-DHPEA-EDA will influence biological activities. PMID:26904279

  13. Modelling the Absorption Measurement Distribution (AMD) for Mrk 509

    Adhikari, T.; Rozanska, A.; Sobolewska, M.; Czerny, B.

    2015-07-01

    Absorption Measurement Distribution (AMD) measures the distribution of absorbing column over a range of ionization parameters of the X-ray absorbers in Seyfert galaxies. In this work, we modeled the AMD in Mrk 509 using its recently published broad band Spectral Energy Distribution (SED). This SED is used as an input for radiative transfer computations with full photoionization treatment using the photoionization codes Titan and Cloudy. Assuming a photoionized medium with a uniform total pressure (gas+radiation), we reproduced the discontunity in the observed AMD distribution which is usually described as the region of thermal instability of the absorber. We also studied the structure and properties of the warm absorber in Mrk 509.

  14. Reconstructing absorption and scattering distributions in quantitative photoacoustic tomography

    Quantitative photoacoustic tomography is a novel hybrid imaging technique aiming at estimating optical parameters inside tissues. The method combines (functional) optical information and accurate anatomical information obtained using ultrasound techniques. The optical inverse problem of quantitative photoacoustic tomography is to estimate the optical parameters within tissue when absorbed optical energy density is given. In this paper we consider reconstruction of absorption and scattering distributions in quantitative photoacoustic tomography. The radiative transport equation and diffusion approximation are used as light transport models and solutions in different size domains are investigated. The simulations show that scaling of the data, for example by using logarithmic data, can be expected to significantly improve the convergence of the minimization algorithm. Furthermore, both the radiative transport equation and diffusion approximation can give good estimates for absorption. However, depending on the optical properties and the size of the domain, the diffusion approximation may not produce as good estimates for scattering as the radiative transport equation. (paper)

  15. Distribution and excretion of a new insect repellent, 14C-DEM, in the mouse after intravenous, cutaneous, and oral administration

    The distribution of 14C after administration of 14C-DEM was qualitatively similar irrespective of the administration route (intravenous, cutaneous or oral). The major accumulation sites were lacrimal and nasal glands, parotis, liver, and kidney. The main excretion was through the urine and only minor quantities through the faeces and the expired gases. It could be confirmed that the new repellent had a low skin uptake. (author)

  16. Distribution and time course of corticosterone excretion in faeces and urine of female mice with varying systemic concentrations

    Kalliokoski, Otto; Hau, Jann; Jacobsen, Kirsten R;

    2010-01-01

    Quantification of corticosterone metabolites excreted in faeces and urine is increasingly being used for assessment of preceding corticosterone concentrations in the circulation. This is a promising approach to non-invasive stress assessment in laboratory rodents. It is however unknown whether th...... currently untested for other strains of mice and species of animals, these findings add credence to the utility of faecal and urinary corticosterone as non-invasive biomarkers for physiological stress.......Quantification of corticosterone metabolites excreted in faeces and urine is increasingly being used for assessment of preceding corticosterone concentrations in the circulation. This is a promising approach to non-invasive stress assessment in laboratory rodents. It is however unknown whether the...... proportions of corticosterone metabolites excreted in faeces and urine may differ, depending on the concentration of corticosterone in blood. This uncertainty undermines the applicability of urinary and faecal corticosterone metabolite measurements as biomarkers for stress. Therefore, the terminal...

  17. Distribution and excretion of 2,3,6,2',3',6'- and 2,4,5,2',4',5'-hexachlorobiphenyl in senescent rats

    The disposition of two symmetrical [14C]hexachlorobiphenyls (HCBs), 2,3,6,2',3',6'-HCB (236) and 2,4,5,2',4',5'-HCB (245), was studied in 24-month-old male Sprague-Dawley rats after iv treatment. Because body composition changes with age, complete dissections were performed on all rats to determine the size of the skin and adipose tissue depots. More than 50% of 236 was metabolized and excreted via the bile into the feces within 2 days. In contrast, 245 redistributed from the liver, muscle, and skin to adipose tissue where it accumulated without being metabolized. Only 2% of the total dose of 245 was excreted primarily in the feces within 21 days. The data obtained in this study were compared to results previously obtained from 2- to 3-month-old rats in this laboratory (Matthews and Tuey, 1980, Toxicol. Appl. Pharmacol. 53, 377-388). Although the general pattern of HCB disposition did not change with age, i.e., metabolism and excretion of 236 versus persistence of 245, there were differences in the rates of elimination and in the tissue levels. There was enhanced metabolite retention in the muscle, skin, and adipose tissue of older animals which suggested an age-related decrease in tissue clearance. The large volume of adipose tissue in these older Sprague-Dawley rats could in part explain this observation. In general, there were few changes in decay rates from tissues or in biliary excretion. Age had a greater effect on the disposition of the persistent 245 than on the metabolizable 236. Thus, changes in body composition seemed to play a major role in age-related changes in the distribution and excretion of polychlorinated biphenyls

  18. Preclinical assessment of the distribution,metabolism, and excretion of S-propargyl-cysteine, a novel H2S donor, in Sprague-Dawley rats

    Yuan-ting ZHENG; Yi-zhun ZHU; Wei-min CAI; Jian-hua ZHU; Guo MA; Qing ZHU; Ping YANG; Bo TAN; Jin-lian ZHANG; Hai-xing SHEN; Jia-lin XU

    2012-01-01

    Aim:To study the distribution,metabolism and excretion of S-propargyl-cysteine (SPRC),a novel hydrogen sulfide (H2S) donor,after oral administration in rats.Methods:Adult Sprague-Dawley rats were used.The tissue distribution of [35S] SPRC-derived radioactivity was measured using a liquid scintillation counter.The plasma protein binding of SPRC was examined using 96-well equilibrium dialysis.The excretion of SPRC in urine,bile and feces was analyzed using the LC-MS/MS method.The major metabolites in rat biomatrices were identified using MRM information-dependent,acquisition-enhanced product ion (MRM-IDA-EPI) scans on API 4000QTrap system.Results:After oral administration of [35S] SPRC at a dose of 75 mg/kg,[35S] SPRC-derived radioactivity displayed broad biological distribution in various tissues of rats,including its target organs (heart and brain) with the highest in kidney.On the other hand,the binding of SPRC to human,rat and dog plasma protein was low.Only 2.18%±0.61% and 0.77%±0.61% of the total SPRC administered was excreted unchanged in the bile and urine.However,neither intact SPRC nor its metabolites were detected in rat feces.The major metabolic pathway in vivo (rat bile,urine,and plasma) was N-acetylation.Conclusion:The preliminary results suggest that SPRC possesses acceptable pharmacokinetic properties in rats.

  19. Retention, distribution, and excretion of 239PuO2 particles labeled with 169Yb in the Rhesus monkey after a single acute inhalation exposure

    Sixteen Rhesus monkeys were exposed to a high fired 239PuO2 aerosol labeled with 169Yb, and retention, distribution, and excretion patterns were determined. After an early rapid clearance phase, which had a half-life of less than one day, the remaining plutonium was retained in the lungs with a half-life that appeared to be greater than 500 days. By 30 days after exposure, 99 percent of the 239Pu in the body was in the lungs. At this time, 6 to 10 percent of the 169Yb burden was in the carcass and skeleton suggesting that there was dissociation of some 169Yb from the particles. The remaining 169Yb activity was in the lungs. There was little 239Pu in the liver, bone, or lymph nodes. The particulate material was cleared rapidly from the gastrointestinal and upper respiratory tracts and appeared in feces over the first four days. The level of 239Pu in feces returned to background by six days. Urinary excretion of 239Pu reached a peak by 8 to 10 days and then remained at a constant rate throughout the remainder of the experiment. These data are useful in calculating radiation dose to a variety of organs and relating this dose to the appearance of late effects from inhaled alpha-emitting particles. (U.S.)

  20. Absorption, distribution, and biliary excretion of cafestol, a potent cholesterol-elevating compound in unfiltered coffees, in mice

    Cruchten, S.T.J. van; Waart, D.R. de; Kunne, C.; Hooiveld, G.J.E.J.; Boekschoten, M.V.; Katan, M.B.; Oude Elferink, R.P.J.; Witkamp, R.F.

    2010-01-01

    Cafestol is a diterpene present in unfiltered coffees. It is the most potent cholesterol-elevating compound present in the human diet. However, the precise mechanisms underlying this effect are still unclear. In contrast, cafestol is also known as a hepatoprotective compound, which is likely to be r

  1. Identification of Absorption, Distribution, Metabolism, and Excretion (ADME) Genes Relevant to Steatosis Using a Systems Biology Approach

    Ensuring chemical safety and sustainability form a main priority of the U.S. Environmental Protection Agency. This entails efforts on multiple fronts to characterize the potential hazard posed by chemicals currently in use and those to be commercialized in the future. The use of ...

  2. INTERACTION BETWEEN GAMMA-HEXACHLOROCYCLOHEXANE AND THE GASTROINTESTINAL MICROFLORA AND THEIR EFFECT ON THE ABSORPTION, BIOTRANSFORMATION, AND EXCRETION OF PARATHION BY THE RAT

    Pretreatment of rats with the organochlorine insecticide lindane reduced the estimated absorption rate of parathion from the gastrointestinal tract. Lindane pretreatment also significantly reduced the metabolism of parathion to p-nitrophenol in vivo. Lindane pretreatment altered ...

  3. Heterotopic excretion of ioxitalamate

    Koester, O.; Figge, M.

    1980-11-01

    The relatively rare case of heterotopic excretion of a recently introduced contrast medium easily excreted by the kidney, is demonstrated by means of 2 examples. In one case, the patient complained of colicky pain in the right flank, whereas tumour nephrectomy had been performed in the other patient. The hypotheses presented in medical literature regarding ectopic excretion of contrast medium, are mentioned, but it does not appear possible to safely explain the observed extrarenal excretions.

  4. Mercury distribution in the skin of beluga (Delphinapterus leucas) and narwhal (Monodon monoceros) from the Canadian Arctic and mercury burdens and excretion by moulting.

    Wagemann, R; Kozlowska, H

    2005-12-01

    Beluga and narwhal skin as a whole (in Inuktitut known as "muktuk") is considered to be a delicacy by native Canadian and Greenland people. Individual strata of the skin, and muscle from 27 beluga from the western, and 20 narwhal from the eastern Canadian Arctic, were analyzed for mercury and the thickness and density of each skin layer was measured. Mercury was not uniformly distributed in the skin, but increased outwardly with each layer. The concentration was only 0.29 and 0.16 microg/g (wet wt) in the innermost layer (dermis) of belugas and narwhal respectively, and 1.5 and 1.4 microg/g (wet wt) in the outermost layer (degenerative epidermis) of beluga and narwhal, respectively. There was a significant (alpha=0.05) association between age and mercury concentration in each skin layer, the regression coefficients progressively increasing from the inner layer (dermis) to the outer layer: 0.011-0.063 microg/g year-1; 0.034 microg/g year-1 for skin as a whole; 0.054 microg/g year-1 for muscle. The concentration of total mercury was 0.84 and 0.59 microg/g (wet wt) in skin as a whole (muktuk) of beluga and narwhal respectively, and 0.12 and 0.03 microg/g in blubber, respectively. The average, total mercury concentration in muscle tissue was 1.4 and 0.81 microg/g wet wt, in beluga and narwhal respectively, exceeding (except for blubber) the Canadian Government's Guideline (0.5 microg/g wet wt) for fish export and consumption. The skin surface area of an average-size beluga and narwhal was estimated (6.10 and 6.50 m2, respectively), as were excretions of mercury through moulting (13,861 and 6721 microg year-1; 14 and 7 mg year-1) for belugas and narwhal, respectively. The whole-body mercury burden (699,300 microg; 700 mg) for a 1000 kg beluga and its various tissues were estimated, as was the fraction of mercury excreted by moulting (2-0.42% of the whole-body burden). Annual mercury burden increments in beluga skin, muscle and the whole body were estimated (2750; 17

  5. In vivo distribution and excretion studies and in vitro blood studies on the kinetics of lead-203 in beagle dogs

    Studies on the kinetics of the distribution of lead-203 in body fluids have been carried out in vitro, and in animal studies using beagle dogs. In vitro, the distribution of carrier free lead-203 between plasma and cells of canine blood at 370C was measured after the addition of isotope. In animal studies, activity in plasma was measured for about 150 hours, and activity in blood cells, urine and feces measured for about 400 hours after exposure to lead-203. Linear compartmental models for distribution of the isotope are presented for both in vitro and in vivo experimental systems. The models contain compartments for both untransformed lead, for isotope added in saline or citric acid, and transformed lead, as obtained by lead-203 incubation in plasma

  6. New Insights in Tissue Distribution, Metabolism, and Excretion of [3H]-Labeled Antibody Maytansinoid Conjugates in Female Tumor-Bearing Nude Rats.

    Walles, Markus; Rudolph, Bettina; Wolf, Thierry; Bourgailh, Julien; Suetterlin, Martina; Moenius, Thomas; Peraus, Gisela; Heudi, Olivier; Elbast, Walid; Lanshoeft, Christian; Bilic, Sanela

    2016-07-01

    For antibody drug conjugates (ADCs), the fate of the cytotoxic payload in vivo needs to be well understood to mitigate toxicity risks and properly design the first in-patient studies. Therefore, a distribution, metabolism, and excretion (DME) study with a radiolabeled rat cross-reactive ADC ([(3)H]DM1-LNL897) targeting the P-cadherin receptor was conducted in female tumor-bearing nude rats. Although multiple components [total radioactivity, conjugated ADC, total ADC, emtansine (DM1) payload, and catabolites] needed to be monitored with different technologies (liquid scintillation counting, liquid chromatography/mass spectrometry, enzyme-linked immunosorbent assay, and size exclusion chromatography), the pharmacokinetic data were nearly superimposable with the various techniques. [(3)H]DM1-LNL897 was cleared with half-lives of 51-62 hours and LNL897-related radioactivity showed a minor extent of tissue distribution. The highest tissue concentrations of [(3)H]DM1-LNL897-related radioactivity were measured in tumor. Complimentary liquid extraction surface analysis coupled to micro-liquid chromatography-tandem mass spectrometry data proved that the lysine (LYS)-4(maleimidylmethyl) cyclohexane-1-carboxylate-DM1 (LYS-MCC-DM1) catabolite was the only detectable component distributed evenly in the tumor and liver tissue. The mass balance was complete with up to 13.8% ± 0.482% of the administered radioactivity remaining in carcass 168 hours postdose. LNL897-derived radioactivity was mainly excreted via feces (84.5% ± 3.12%) and through urine only to a minor extent (4.15% ± 0.462%). In serum, the major part of radioactivity could be attributed to ADC, while small molecule disposition products were the predominant species in excreta. We show that there is a difference in metabolite profiles depending on which derivatization methods for DM1 were applied. Besides previously published results on LYS-MCC-DM1 and MCC-DM1, maysine and a cysteine conjugate of DM1 could be

  7. Comparative effects of ten dithiocarbamate and thiuram compounds on tissue distribution and excretion of lead in rats

    The dithiocarbamate and thiuram compounds, including disulfiram, were compared for their efficacies in influencing tissue distribution of a trace dose of intravenously injected lead plus 203Pb in rats. The tested compounds were sodium diethyldithiocarbamate (DEDTC), sodium dimethyldithiocarbamate (DMDTC), tetraethylthiuram disulfide (disulfiram), a complex of zinc and manganese ethylenebisdithiocarbamate (mancozeb), manganese ethylenebisdithiocarbamate (maneb), sodium monomethyldithiocarbamate (metham), zinc propylene bisdithiocarbamate (propineb), tetramethylthiuram disulfide (thiram), zinc ethylenebisdithiocarbamate (zineb), and zinc dimethyldithiocarbamate (ziram). The results of this study show that interactions can occur between lead and DEDTC, DMDTC, disulfiram, metham, thiram, and ziram, resulting in increased levels of lead in brain and probably potentiation of the neurotoxic effects of lead

  8. Comparative effects of ten dithiocarbamate and thiuram compounds on tissue distribution and excretion of lead in rats

    Oskarsson, A.

    1987-10-01

    The dithiocarbamate and thiuram compounds, including disulfiram, were compared for their efficacies in influencing tissue distribution of a trace dose of intravenously injected lead plus /sup 203/Pb in rats. The tested compounds were sodium diethyldithiocarbamate (DEDTC), sodium dimethyldithiocarbamate (DMDTC), tetraethylthiuram disulfide (disulfiram), a complex of zinc and manganese ethylenebisdithiocarbamate (mancozeb), manganese ethylenebisdithiocarbamate (maneb), sodium monomethyldithiocarbamate (metham), zinc propylene bisdithiocarbamate (propineb), tetramethylthiuram disulfide (thiram), zinc ethylenebisdithiocarbamate (zineb), and zinc dimethyldithiocarbamate (ziram). The results of this study show that interactions can occur between lead and DEDTC, DMDTC, disulfiram, metham, thiram, and ziram, resulting in increased levels of lead in brain and probably potentiation of the neurotoxic effects of lead.

  9. Toxicity, tissue distribution and excretion of 46ScCl3 and 46Sc-EDTA in mice

    The acute toxicity, differential distribution in tissue, and elimination of ScCl3, 46ScCl3, Sc-EDTA and 46Sc-EDTA, in mice, has been investigated. The LD50sup(24hr) doses for ScCl3 were 440 and 24 mg kg-1 respectively after intraperitioneal and intravenous injection, and 720 and 108 mg kg-1 respectively for Sc-EDTA. 46ScCl3 was extensively deposited in the liver and the spleen. 46Sc-EDTA was rapidly taken up by the kidney with subsequent elimation via the urine. While-body desaturation kinetics for 46Sc-EDTA were found to fit a three compartmental model. The fast elimination phase (T1/2 = 12.75 min; K = 0.05540 min-1) accounted for 74.6% of the dose; the intermediate phase (T1/2 = 40.2 min; K = 0.01722 min-1) for 21.8%, and the slow (T1/2 = 5351 min; K = 0.00013 min-1) for 3.6% of the dose. (author)

  10. Polarized Synchrotron Emissivities and Absorptivities for Relativistic Thermal, Power-Law, and Kappa Distribution Functions

    Pandya, Alex; Chandra, Mani; Gammie, Charles F

    2016-01-01

    Synchrotron emission and absorption determine the observational appearance of many astronomical systems. In this paper, we describe a numerical scheme for calculating synchrotron emissivities and absorptivities in all four Stokes parameters for arbitrary gyrotropic electron distribution functions, building on earlier work by Leung, Gammie, and Noble. We use this technique to evaluate the emissivities and the absorptivities for a thermal (Maxwell-J\\"uttner), isotropic power-law, and isotropic kappa distribution function. The latter contains a power-law tail at high particle energies that smoothly merges with a thermal core at low energies, as is characteristic of observed particle spectra in collisionless plasmas. We provide fitting formulae and error bounds on the fitting formulae for use in codes that solve the radiative transfer equation. The numerical method and the fitting formulae are implemented in a compact C library called ${\\tt symphony}$. We find that: the kappa distribution has a source function th...

  11. Metabolism of 2- and 3-tert-butyl-4-hydroxyanisole (2- and 3-BHA) in the rat (I): excretion of BHA in urine, feces and expired air and distribution of BHA in the main organs

    The mechanism of the carcinogenic or toxic action of BHA on rat forestomach was examined by studies on the excretion and tissue distribution of radioactivity in F344 male rats given tert-butyl or methoxylabelled 3-BHA orally. Within 2 days after a single oral dose of labelled BHA at 1 g/kg body wt, 87-96% of the 14C was excreted, mainly in urine with smaller amounts in the feces and expired air. More 14C was found in the tissues of rats given the methoxy-labelled compounds. The distributions of 14C in the forestomach and the glandular stomach were similar. At 168 h after treatment, more 14C was found in the forestomach of rats given 2-BHA than in that of rats given 3-BHA. These results indicate that excretion of BHA is rapid, that 4-0-methyl demethylation may take place readily and that demethylated methyl group may become distributed non-specifically in tissues. The carcinogenic or toxic action of BHA on the forestomach does not seem to be due to accumulation of BHA in the forestomach

  12. Pharmacokinetics, tissue distribution and excretion of 40kDa PEG and PEGylated rFVIII (N8-GP) in rats.

    Bjørnsdottir, Inga; Sternebring, Ola; Kappers, Wendela A; Selvig, Helle; Kornø, Hanne T; Kristensen, Jesper B; Bagger, Morten A

    2016-05-25

    The biologic fate of the [(3)H]PEG-moiety incorporated into N8-GP was evaluated based on single i.v. bolus doses to rats. Furthermore, the 40kDa [(3)H]PEG-moiety was given separately to rats by single i.v. bolus doses, to investigate if the pharmacokinetics were dose-dependent. For both compounds, plasma pharmacokinetics, distribution and excretion pathways were investigated, based on total radioactivity measurements ([(3)H]N8-GP: 0.17-4.1mg/kg;~1300-30,000U/kg, PEG load of ~0.03-0.7mg/kg); ([(3)H]PEG: 0.6, 1, 12, 100 and 200mg/kg). The plasma concentration of the intact N8-GP conjugate was also measured by ELISA. After single i.v. administration to rats, both [(3)H]N8-GP and [(3)H]PEG were shown to be widely distributed, mainly in highly vascularized tissues, with the lowest levels of radioactivity found in the CNS. Though a slow elimination of radioactivity was observed over the 12-week study period, approximately half of the radioactive dose of either compound was removed from the body 1week post-dose. The radioactivity was eliminated mainly via the kidney into urine but also via the liver into feces, with a larger fraction found in the feces for [(3)H]N8-GP. Elimination of the 40kDa PEG-moiety was shown to be dose-dependent with faster elimination at lower dose levels. The clinical dose of N8-GP provides a substantially lower PEG exposure (50-75U/kg; PEG load of <0.002mg/kg) when compared to the PEG doses investigated in this paper (0.03-200mg/kg). This may imply an even faster clearance of the PEG-moiety after N8-GP administration of clinically relevant doses. PMID:26517963

  13. Analytical algorithm to determine the spherical particle size distribution from spectral absorption measurements

    Zhao, Jian-Qi; Li, Jiangnan

    2015-11-01

    A modified anomalous diffraction theory (MADT) by including the effects of reflection and refraction is proposed. With respect to MADT, an analytical technique for retrieval of spherical particle size distribution (PSD), based on absorption was developed. Also, an MADT transform pair between the size distribution and the absorption spectrum was constructed. This provides a new tool to study the related particle optical properties. By Gaver-Stehfest inversion method, the derived complex-inversion formula is finally converted into the new real-inversion formula so that the measured absorption data can be applied directly. The inversion experiments show that the use of extended precision instead of double precision arithmetic can produce more reliable results at the expense of CPU time. The effects of complex refractive index on retrieval of PSD were examined. Also it was found that an appropriate reduction of the truncation number with the smoothing technique improved the anti-noise ability for the algorithm.

  14. Dermal absorption of phthalate diesters in rats

    This study examined the extent of dermal absorption of a series of phthalate diesters in the rat. Those tested were dimethyl, diethyl, dibutyl, diisobutyl, dihexyl, di(2-ethylhexyl), diisodecyl, and benzyl butyl phthalate. Hair from a skin area (1.3 cm in diameter) on the back of male F344 rats was clipped, the [14C]phthalate diester was applied in a dose of 157 mumol/kg, and the area of application was covered with a perforated cap. The rat was restrained and housed for 7 days in a metabolic cage that allowed separate collection of urine and feces. Urine and feces were collected every 24 hr, and the amount of 14C excreted was taken as an index of the percutaneous absorption. At 24 hr, diethyl phthalate showed the greatest excretion (26%). As the length of the alkyl side chain increased, the amount of 14C excreted in the first 24 hr decreased significantly. The cumulative percentage dose excreted in 7 days was greatest for diethyl, dibutyl, and diisobutyl phthalate, about 50-60% of the applied 14C; and intermediate (20-40%) for dimethyl, benzyl butyl, and dihexyl phthalate. Urine was the major route of excretion of all phthalate diesters except for diisodecyl phthalate. This compound was poorly absorbed and showed almost no urinary excretion. After 7 days, the percentage dose for each phthalate that remained in the body was minimal and showed no specific tissue distribution. Most of the unexcreted dose remained in the area of application. These data show that the structure of the phthalate diester determines the degree of dermal absorption. Absorption maximized with diethyl phthalate and then decreased significantly as the alkyl side chain length increased

  15. Tissue distribution, metabolism, and excretion of 14C-TCDD in a TCDD-susceptible and a TCDD-resistant rat straina

    A comparative study was carried out in the most TCDD-resistant [Han/Wistar (H/W), LD50>3000 μg/kg] and the most TCDD-susceptible [Long-Evans (L-E), LD50 about 10 μg/kg] rat strain to assess the significance of kinetic factors in TCDD toxicity. Young adult males of both strains were administered 5 μg/kg (1.9 μCi/kg) 14C-TCDD intraperitoneally. Four rats per strain were killed at 4 hr, 1, 4, 8, 16 and 32 days after exposure. A total of 22 tissues along with blood and serum were sampled for liquid scintillation counting. From half of the animals, daily urine and faeces were also analyzed. In addition, 3 rats per strain were given 50 μg/kg (19 μCi/kg) 14C-TCDD and prepared for whole-body autoradiography after 1, 4 or 8 days. The livers of two rats per strain killed at 4 hr, 4 or 16 days, and the excreta from two rats of both strains collected on days 1-4, 5-8, 13-16, and 29-32 after exposure were analyzed for metabolites of TCDD by high pressure liquid chromatography. The label was mainly excreted in faeces as metabolites of TCDD, and the half-life of elimination was 20.8 (L-E) or 21.9 (H/W) days. A very similar overall distribution pattern was observed in both strains irrespective of dose, and the liver was the major site of accumulation. Practically all liver 14C-activity was found as the parent compound. Moderate strain-related differences were observed in the thyriod, thymus, prostate, adrenals, and brown and white fat, where lower values were recorded in H/W rats. Site-dependent variation was detected in the brain. The results do not support the view that TCDD metabolism or disposition would have a major impact on the strain difference in TCDD lethality. (author)

  16. Automated low energy photon absorption equipment for measuring internal moisture and density distributions of wood samples

    Automated equipment for measuring the moisture and density distributions of wood samples was developed. Using a narrow beam of gamma rays, the equipment scans the wood samples, which are placed on the moving belt. The moisture measurement is based on the 241Am photon absorption technique (59.5 keV), where the difference of the linear absorption coefficients of the moist and dry wood is measured. The method requires no knowledge of the thickness of the specimen. The density estimation method is based on the measurement of the linear attenuation coefficient of wood. Comprehensive software including image processing was developed for treatment of the numerical values of the measurements. (author)

  17. Absorption of electron cyclotron waves by super-thermal electron velocity distribution in Tokamak plasmas

    We consider a Tokamak plasma in which the distribution of electron velocities in the direction paralletl to the magnetic field has a monotonically decreasing superthermal tail. A fully three-dimensional ray-tracing code is used to calculate the absorption of the extraordinary mode in the nonrelativistic limit. The results indicate that small tails (tail fraction <= 0.5%) can significantly affect wave absorption at low densities. In a high-density plasma where the extraordinary mode cutoff is present, tail electrons can cause substantial absorption. The use of a gyrotron with frequency much less than the central electron cyclotron frequency with an outside launch position is found to be verg effective in the presence of tail electrons. (author)

  18. Distribution of radiosodium in the various organs of Sorghum after root absorption

    The kinetics of Na22 migration corroborate the distribution pattern of the non-radioactive element after root absorption: the sodium content of the leaf laminae is very low whereas a building-up is observed in the conductive tissues, particularly in the roots. After absorption, sodium seems to be rapidly translocated to all the organs, then moves downwards to accumulate in the roots; this phenomenon may be a way, for the plant, to fight sodium intoxication. The absorption of radiosodium is independent of the specific activity of the nutrient solution and appears to be related to its volumic activity. Thus, sodium is not taken up selectively by the roots of Sorghum; its translocation mechanism is therefore of the passive type

  19. Polarized Synchrotron Emissivities and Absorptivities for Relativistic Thermal, Power-law, and Kappa Distribution Functions

    Pandya, Alex; Zhang, Zhaowei; Chandra, Mani; Gammie, Charles F.

    2016-05-01

    Synchrotron emission and absorption determine the observational appearances of many astronomical systems. In this paper, we describe a numerical scheme for calculating synchrotron emissivities and absorptivities in all four Stokes parameters for arbitrary gyrotropic electron distribution functions, building on earlier work by Leung, Gammie, and Noble. We use this technique to evaluate the emissivities and the absorptivities for a thermal (Maxwell–Jüttner), isotropic power-law, and an isotropic kappa distribution function. The latter contains a power-law tail at high particle energies that smoothly merges with a thermal core at low energies, as is characteristic of observed particle spectra in collisionless plasmas. We provide fitting formulae and error bounds on the fitting formulae for use in codes that solve the radiative transfer equation. The numerical method and the fitting formulae are implemented in a compact C library called symphony. We find that the kappa distribution has a source function that is indistinguishable from a thermal spectrum at low frequency and transitions to the characteristic self-absorbed synchrotron spectrum, \\propto {ν }5/2, at high frequency; the linear polarization fraction for a thermal spectrum is near unity at high frequency; and all distributions produce O(10%) circular polarization at low frequency for lines of sight sufficiently close to the magnetic field vector.

  20. Increased urinary orosomucoid excretion

    Christiansen, M S; Iversen, K; Larsen, C T;

    2009-01-01

    OBJECTIVE: In a previous study, urinary orosomucoid excretion rate (UOER) independently predicted cardiovascular mortality in patients with type 2 diabetes. The aim of the present study was to determine whether increased UOER is associated with cardiovascular risk factors such as inflammation, im...

  1. Effect of lead in the laboratory mouse. 1. Influence of pregnancy upon absorption, retention, and tissue distribution of radiolabeled lead

    Whole-body retention and excretion following a single oral dose of radiolabeled lead (203Pb) in chronically lead-exposed pregnant BK:W mice were examined over 10-13 days. This was compared with values in similarly treated nonpregnant females and in ip injected females. Whole-body and bone retention were greater in injected than in orally dosed nonpregnant females; gastrointestinal absorption was estimated from this difference. Whole-body retention in the pups was measured at birth and at the end of the experiment. Whole-body retentions in pregnant females and in their pups at birth were significantly raised after treatment at Gestational Day 17, but not after treatment at Gestational Day 11, 14, 20, 23, or 26. Pup body burdens at birth were significantly and positively correlated with maternal retention. Measurement of radioactivity in bone, kidney, brain, heart, and liver of adults at the end of the experiments showed significantly increased levels in bone and kidney from females treated at Gestational Day 17 and in bone from females treated at Gestational Day 11. Lead excretion did not differ significantly among the groups but the total lead content of the femur was significantly raised in females treated at Gestational Days 17 and 26. Thus, these experiments provide evidence that lead absorption and retention in mice are markedly increased in the latter stages of pregnancy

  2. Tissue distribution and excretion of myosmine after i.v. administration to Long-Evans rats using quantitative whole-body autoradiography

    Glas, Susanna; Tyroller, Stefan; Zwickenpflug, Wolfgang; Richter, Elmar [Ludwig-Maximilians University of Munich, Walther Straub Institute of Pharmacology and Toxicology, Munich (Germany); Steiner, Kurt; Kiefer, Gudrun [Institute of Drug Metabolism and Pharmakokinetics, Merck KGaA, Grafing (Germany)

    2007-03-15

    Occurrence of the tobacco alkaloid myosmine has been proven in various staple foods, vegetables and fruits. Myosmine can be easily activated by nitrosation yielding 4-hydroxy-1-(3-pyridyl)-butanone (HPB) and the esophageal carcinogen N'-nitrosonornicotine. Most of the reaction products after myosmine peroxidation were also identified as urinary metabolites after oral administration to rats. Whole-body autoradiography with freeze dried or multiple solvent extracted tissue sections was used to trace [2'-{sup 14}C]myosmine (0.1 mCi/kg bw) 0.1, 0.25, 1, 4 and 24 h after i.v. injection in Long-Evans rats. In addition, in vitro binding of radioactivity to esophageal and eye tissue was determined and excretion of radioactivity via urine and feces was quantified. Radioactivity is rapidly eliminated by renal excretion. Approximately 30% of the administered radioactivity was recovered in urine within the first 4 h and excretion with urine (72%) and feces (15%) was nearly complete after 24 h. A rapid concentration of radioactivity can be seen in the stomach and in the salivary and lachrymal glands. Rats killed 1 and 4 h after treatment showed by far the highest labeling in the accessory genital gland. High levels of nonextractable radioactivity were present in esophageal tissue and melanin. The half lives for the disappearance of radioactivity from various tissues are in the order of about 1 h. Eye and esophagus sections both showed nonextractable labeling after in vitro incubation with {sup 14}C-myosmine. In conclusion, the toxicological significance of myosmine accumulation in esophagus and accessory genital gland requires further investigations. Hair analysis might be applicable for myosmine biomonitoring, because of possible enrichment in melanin containing tissues. (orig.)

  3. X-ray absorption of the Hg distribution in metal-halide lamps

    Nimalasuriya, T; Zhu, X; Ridderhof, E J; Haverlag, M; Denisova, N; Stoffels, W W; Mullen, J J A M van der [Department of Applied Physics, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven (Netherlands)

    2008-01-21

    Spatial temperature profiles of metal-halide lamps have been acquired using x-ray absorption of the Hg density distribution. The temperature profiles were determined by combining the measured absorption of the spatially resolved Hg density with the wall temperature. The data analysis of x-ray absorption is extensive. After the necessary image reconstruction, the line integrated density profile needs to be Abel inverted. The solution from the Abel inversion is stabilized with the Tikhonov regularization parameter. The previous method for x-ray absorption developed in our group has been modified and improved by utilizing the following: (1) a larger outer bulb, (2) the corrections for x-ray scattering on the lamp materials, (3) an optimum value of Tikhonov regularization parameter {mu}, and (4) employing a higher degree of polynomials used for the Abel inversion. For a similar lamp as reported previously by Zhu, we found an axis temperature of 6200 K instead of 5200 K. The higher temperature is similar to what is found using optical spectroscopic methods. Typical results from a metal-halide lamp with and without salts are shown.

  4. X-ray absorption of the Hg distribution in metal-halide lamps

    Spatial temperature profiles of metal-halide lamps have been acquired using x-ray absorption of the Hg density distribution. The temperature profiles were determined by combining the measured absorption of the spatially resolved Hg density with the wall temperature. The data analysis of x-ray absorption is extensive. After the necessary image reconstruction, the line integrated density profile needs to be Abel inverted. The solution from the Abel inversion is stabilized with the Tikhonov regularization parameter. The previous method for x-ray absorption developed in our group has been modified and improved by utilizing the following: (1) a larger outer bulb, (2) the corrections for x-ray scattering on the lamp materials, (3) an optimum value of Tikhonov regularization parameter μ, and (4) employing a higher degree of polynomials used for the Abel inversion. For a similar lamp as reported previously by Zhu, we found an axis temperature of 6200 K instead of 5200 K. The higher temperature is similar to what is found using optical spectroscopic methods. Typical results from a metal-halide lamp with and without salts are shown

  5. Urinary excretion of cadmium and zinc among persons from Sweden

    Elinder, C.G.; Kjellstrom, T.; Linnman, L.; Pershagen, G.

    1978-06-01

    Cadmium and zinc concentrations in the urine of 132 Swedes, including 50 pairs of identical twins, were measured. Atomic absorption spectrophotometry procedures were developed for the analysis. Cadmium concentration increased with age and was higher among smokers than among nonsmokers. Estimated 24-hr excretion of cadmium among nonsmokers increased from about 0.25 to 0.40 ..mu..g in persons from 20 to 70 years old. The 24-hr cadmium excretions among nonsmokers in different age-groups fitted better to total kidney burden than to daily cadmium intake from food. Zinc excretion, on the other hand, decreased after the age of 20.

  6. Disorders of absorption of olive oil and albumin labelled with iodine 125 in rats receiving tetracycline

    The influence of tetracycline on absorption and distribution of olive oil and albumin labelled with iodine 125 was studied in the intestines, liver, blood and kidneys. In rats which received tetracycline in therapeutic doses no detectable changes in absorption and distribution of labelled olive oil were noticed. In rats which received the double doses, disorders of absorption and distribution were observed in the small intestine and increased retention in the liver. The higher doses of tetracycline had no significant effect on absorption of labelled albumin, but transport and excretion were disturbed. (author)

  7. Conservation of bubble size distribution during gas reactive absorption in bubble column reactors

    P. L.C. LAGE

    1999-12-01

    Full Text Available Conservation of the bubble size distribution function was applied to the reactive absorption of carbon dioxide in a bubble column reactor. The model developed was solved by the method of characteristics and by a Monte Carlo method. Simulations were carried out using simplified models for the liquid phase and for the gas-liquid mass transfer. Predictions of gas holdup and outlet gas composition showed that the concept of a mean bubble diameter is not applicable when the bubble size distribution is reasonably polydispersed. In these cases, the mass mean velocity and the numerical mean velocity of the bubbles are very different. Therefore, quantification of the polydispersion of bubbles was shown to be essential to gas-phase hydrodynamics modeling.

  8. Stress modification of the kinetic of 137Cs absorption and primary pattern of intercompartments distribution

    The kinetic of 137Cs absorption by pea seedlings and the possibility of alteration of the qualitative and quantitative characteristics of this process were investigated. Gamma irradiation of dry seeds of pea at doses of 25-50 Gy brings about a global change in the kinetic and concentration curves of the active and passive 137Cs uptake by the plant roots. The first and second phases of the kinetic curve, which mirror the passive stage of absorption, and the type of the concentration curve in general, were changed. The level of radionuclide accumulation at this passive stage and the retention for the apoplast-symplast passage increase significantly. Changes in the Michaelis-Menten parameters of the concentration curves were also observed. The changes mirror changes in the radionuclide distribution in the symplast-apoplast system. The time of 137Cs retention for the root-stem transition increased from 0.5 min to 1 min. This investigation suggests that the cation exchange capacity of the parts and structures of a plant is among the main factors which determine the primary intercompartment distribution of 137Cs as nonbiogenous mineral elements

  9. Gamma camera imaging for studying intestinal absorption and whole-body distribution of selenomethionine

    Madsen, Jan L.; Sjögreen-Gleisner, Katarina; Elema, Dennis Ringkjøbing;

    2014-01-01

    ]SeMet was retained within the body after 7 d. In contrast, the measured excretion in urine and faeces for the 7 d period was 8•2 (SD 1•1)% of the activity. Time–activity curves were generated for the whole body, stomach, liver, abdomen (other than the stomach and the liver), brain and femoral muscles. Gamma camera...

  10. Enhancement of light absorption in polyazomethines due to plasmon excitation on randomly distributed metal nanoparticles

    Wróbel, P.; Antosiewicz, T. J.; Stefaniuk, T.; Ciesielski, A.; Iwan, A.; Wronkowska, A. A.; Wronkowski, A.; Szoplik, T.

    2015-05-01

    In photovoltaic devices, metal nanoparticles embedded in a semiconductor layer allow the enhancement of solar-toelectric energy conversion efficiency due to enhanced light absorption via a prolonged optical path, enhanced electric fields near the metallic inclusions, direct injection of hot electrons, or local heating. Here we pursue the first two avenues. In the first, light scattered at an angle beyond the critical angle for reflection is coupled into the semiconductor layer and confined within such planar waveguide up to possible exciton generation. In the second, light is trapped by the excitation of localized surface plasmons on metal nanoparticles leading to enhanced near-field plasmon-exciton coupling at the peak of the plasmon resonance. We report on results of a numerical experiment on light absorption in polymer- (fullerene derivative) blends, using the 3D FDTD method, where exact optical parameters of the materials involved are taken from our recent measurements. In simulations we investigate light absorption in randomly distributed metal nanoparticles dispersed in polyazomethine-(fullerene derivative) blends, which serve as active layers in bulkheterojunction polymer solar cells. In the study Ag and Al nanoparticles of different diameters and fill factors are diffused in two air-stable aromatic polyazomethines with different chemical structures (abbreviated S9POF and S15POF) mixed with phenyl-C61-butyric acid methyl ester (PCBM) or [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM). The mixtures are spin coated on a 100 nm thick Al layer deposited on a fused silica substrate. Optical constants of the active layers are taken from spectroscopic ellipsometry and reflectance measurements using a rotating analyzer type ellipsometer with auto-retarder performed in the wavelength range from 225 nm to 2200 nm. The permittivities of Ag and Al particles of diameters from 20 to 60 nm are assumed to be equal to those measured on 100 to 200 nm thick metal films.

  11. X-ray absorption of the Hg distribution in a commercial metal-halide lamp

    Nimalasuriya, T; Zhu, X; Ridderhof, E J; Beks, M L; Haverlag, M; Denisova, N; Stoffels, W W; Mullen, J J A M van der [Department of Applied Physics, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven (Netherlands)], E-mail: T.Nimalasuriya@tue.nl

    2008-07-21

    The radial temperature profiles of a commercial metal-halide lamp and of lamps containing its individual components have been acquired using x-ray absorption of Hg density distribution. The temperature profiles were determined by combining the measured absorption of the spatially resolved Hg density with the wall temperature. The lamps studied were a commercial lamp, i.e. the Philips CDM-T 70 W/830, and identically shaped lamps containing NaI, DyI{sub 3} and TlI separately. It was found that the element Dy contracts the arc, Na broadens the arc while Tl causes the arc to have so-called 'shoulders'. Combined in the commercial lamp this leads to a wall-stabilized arc without contraction and 'shoulders'. A reproducibility test with identical lamps was also made and showed that the uncertainty in the temperature profile is about 8% for the absolute temperature and only 1.6% for the actual shape of the profile.

  12. Oral absorption and tissue distribution of a new squalenoyl anticancer nanomedicine

    Harivardhan Reddy, L.; Ferreira, Humberto; Dubernet, Catherine [Univ. Paris-Sud XI, Faculte de Pharmacie, UMR CNRS 8612, IFR 141 (France); Mouelhi, Sinda Lepetre; Desmaele, Didier [Universite Paris XI, Faculte de Pharmacie, UMR CNRS 8076 Biocis (France); Rousseau, Bernard [CEA, Bio Organic Chemistry and Labeled Compounds Division (France); Couvreur, Patrick [Univ. Paris-Sud XI, Faculte de Pharmacie, UMR CNRS 8612, IFR 141 (France)], E-mail: patrick.couvreur@u-psud.fr

    2008-05-15

    Recently, we had discovered that the linkage of nucleoside analogues to squalene, a precursor in the sterol biosynthesis, led to amphiphilic molecules, which self-organized in water as nanoassemblies of 100-300 nm in diameter, irrespective of the nucleoside analogue used. Thus, it was observed that the 4-(N)-trisnorsqualenoylgemcitabine (SQdFdC), the squalenoyl prodrug of the anticancer nucleoside analogue gemcitabine, was impressively more active than its parent compound gemcitabine, both in vitro and in vivo on experimental leukaemia. Since squalene, which is a natural constituent of shark liver and olive oil, is known to be absorbed orally, we investigated in this short note the absorption and tissue distribution of {sup 3}H-radiolabelled SQdFdC nanoassemblies comparatively to {sup 3}H-gemcitabine after oral administration to mice. Whereas gemcitabine was found to be rapidly absorbed (t{sub max} = 1 h), this compound underwent a rapid clearance from the plasma. Conversely, the SQdFdC nanoassemblies displayed slower absorption followed by the progressive tissue accumulation, and they exhibited a lower clearance rate. The accumulation of the SQdFdC nanoassemblies in tissues such as pancreas, thymus, lung, liver and spleen (except at 1 h post-administration) was similar to that of the gemcitabine, yet exhibited significantly greater penetration and retention into the stomach and intestinal tissues comparatively to gemcitabine. Thus, the SQdFdC nanoassemblies could be of potential interest in the treatment of gastrointestinal tumours by oral route.

  13. Do changes in the azimuthal distribution of maize leaves over time affect canopy light absorption?

    In maize canopies, when modelling the architecture and light regime one usually assumes leaf azimuths are distributed uniformly. Once we had demonstrated azimuthal re-orientation of maize leaves during the vegetative phase, we tested the weight of this hypothesis on the light absorbed daily by the canopy. We thus modelled the three-dimensional (3D) geometry of maize canopies with various plant densities and at different developmental stages using plant digitizing under field conditions. We simulated radiative transfer using a volume-based approach within actual and hypothetical canopies, obtained by simply rearranging leaf azimuths. Simulations indicated that changes to horizontal heterogeneity have little effect on daily light absorption efficiency. It is concluded that changes in leaf azimuths do not have to be taken into account in crop-functioning models. (author)

  14. Acidosis and Urinary Calcium Excretion

    Alexander, R Todd; Cordat, Emmanuelle; Chambrey, Régine;

    2016-01-01

    Metabolic acidosis is associated with increased urinary calcium excretion and related sequelae, including nephrocalcinosis and nephrolithiasis. The increased urinary calcium excretion induced by metabolic acidosis predominantly results from increased mobilization of calcium out of bone and...... renal tubule and then discuss why not all gene defects that cause renal tubular acidosis are associated with hypercalciuria and nephrocalcinosis....

  15. Determination of the Tissue Distribution and Excretion by Accelerator Mass Spectrometry of the Nonadecapeptide 14C-Moli1901 in Beagle dogs after Intratracheal Instillation

    Rickert, D E; Dingley, K H; Ubick, E; Dix, K J; Molina, L

    2004-07-02

    Administration of {sup 14}C-Moli1901 (duramycin, 2622U90), a 19 amino acid polycyclic peptide by intratracheal instillation (approximately 100 {micro}g) into the left cranial lobe of the lung of beagle dogs resulted in retention of 64% of the dose in the left cranial lobe for up to 28 days. In this study, we used accelerator mass spectrometry (AMS) to quantify Moli901 following administration of only 0.045 {micro}Ci of {sup 14}C-Moli901 per dog. Limits of quantitation of AMS were 0.03 (urine) to 0.3 (feces) ng equiv. Moli1901/g. Whole blood and plasma concentrations of {sup 14}C were <5ng/ml at all times after the dose. Concentrations of {sup 14}C in whole blood and plasma declined over the first day after the dose and rose thereafter, with the rise in plasma concentrations lagging behind those in whole blood. During the first 3 days after the dose, plasma accounted for the majority of {sup 14}C in whole blood, but after that time, plasma accounted for only 25-30% of the {sup 14}C in whole blood. Tissue (left and right caudal lung lobe, liver, kidney, spleen, brain) and bile concentrations were low, always less than 0.25% the concentrations found in the left cranial lung lobe. Approximately 13% of the dose was eliminated in urine and feces in 28 days, with fecal elimination accounting for about 10% of the dose. The data presented here are consistent with that obtained in other species. Moli1901 is slowly absorbed and excreted from the lung, and it does not accumulate in other tissues. Moli1901 is currently in the clinic and has proven to be safe in single dose studies in human volunteers and cystic fibrosis patients by the inhalation route. No information on the disposition of the compound in humans is available. This study in dogs demonstrates the feasibility of obtaining that information using {sup 14}C-Moli1901 and AMS.

  16. Complete Biological Evaluation of Therapeutical Radiopharmaceuticals in Rodents, Laboratory Beagles and Veterinary Patients - Preclinical Distribution-, Kinetic-, Excretion-, Internal Dosimetry-, Radiotoxicological-, Radiation Safety- and Efficacy Data

    The research and development of various novel therapeutical radiopharmaceuticals is a huge demand in many laboratories world-wide. Beside of multiple bone metastases pain-palliation and radiosynovectomy agents a number of specific radiopharmaceutical applicants mainly for oncological applications are in the pipeline. Numerous in vitro methods are available in the first line to test the radiolabelling efficiency, the possible radioactive and non-labelled impurities, the stability of the label at different conditions and mediums, and some specific characteristics of radiopharmaceutical applicants eg.: receptor binding assays, antigen-antibody assays. But, still before human clinical trials there are several questions to be solved in regards of toxicology, radiotoxicology, radiation safety and maybe most importantly the efficacy tasks. All these issues cannot be answered without animal tests. Several decades back animal tests in radiopharmacy meant only standard bioassays in a large number of healthy rodents. Later on pathological models eg.: human tumor xenografts in immunodeficient animals came-out and through them radiopharmaceutical tumor-uptake by the targets were available to evaluate in vivo as well. Xenografts are still popular and widely used models in the field but instead of wide-scaled bioassays nowadays repeated scintiscans or hybrid images (SPECT/CT, PET/CT) are more and more often used to answer kinetic-, excretion-, tumor uptake, internal dosimetry (Minimum Effective Dose, Maximum Tolerable Dose, critical organ doses, tumor doses) questions. Greater animals like laboratory Beagles are more closely in size, clinical and metabolic parameters to the human objects so playing a more perfect role of human medical doctor and especially veterinary patients. Easy to understand that many of the spontaneously occurring companion animal diseases are a good model of human pathological diseases. The need of a better diagnosis and treatment of that animals meets with

  17. Absorption and distribution of different form of nitrogen in sweet pepper

    The absorption and utilization of different form of nitrogen in sweet pepper were studied. The result showed that NH4+-N was favourable to growth of sweet pepper at seedling period and plant developing period and NO3--N was favourable at fruiting period. The utilization of the same form of nitrogen was quite different when N applied in different period. The utilization rate of nitrogen fertilizer dressed at fruiting was the highest (41.8%-45.8%), while that of the basal manure was the lowest (33.6%-36.7%). 75% of the nitrogen up taken from basal manure and fertilizer dressed in plant developing period was distributed in stems and leaves, more than 60% of nitrogen dressed in fruiting period was distributed in fruit. The analysis of fertilizer-N and soil-N in sweet pepper plant indicated that about 60% of plant-N was derived from soil-N and about 40% of plant-N was derived from fertilizer-N

  18. Comparing Spatial Distributions of Solar Prominence Mass Derived from Coronal Absorption

    Gilbert, Holly; Kilper, Gary; Alexander, David; Kucera, Therese

    2010-01-01

    In the present work we extend the use of this mass-inference technique to a sample of prominences observed in at least two coronal lines. This approach, in theory, allows a direct calculation of prominence mass and helium abundance and how these properties vary spatially and temporally. Our motivation is two-fold: to obtain a He(exp 0)/H(exp 0) abundance ratio, and to determine how the relative spatial distribution of the two species varies in prominences. The first of these relies on the theoretical expectation that the amount of absorption at each EUV wavelength is well-characterized. However, in this work we show that due to a saturation of the continuum absorption in the 625 A and 368 A lines (which have much higher opacity compared to 195 A-) the uncertainties in obtaining the relative abundances are too high to give meaningful estimates. This is an important finding because of its impact on future studies in this area. The comparison of the spatial distribution of helium and hydrogen presented here augments previous observational work indicating that cross-field diffusion of neutrals is an important mechanism for mass loss. Significantly different loss timescales for neutral He and H (helium drains much more rapidly than hydrogen) can impact prominence structure, and both the present and past studies suggest this mechanism is playing a role in structure and possibly dynamics. Section 2 of this paper contains a description of the observations and Section 3 summarizes the method used to infer mass along with the criteria imposed in choosing prominences appropriate for this study. Section 3 also contains a discussion of the problems due to limitations of the available data and the implications for determining relative abundances. We present our results in Section 4, including plots of radial-like scans of prominence mass in different lines to show the spatial distribution of the different species. The last section contains a discussion summarizing the importance

  19. Effect of high-dose growth hormone and glutamine on body composition, urine creatinine excretion, fatty acid absorption, and essential fatty acids status in short bowel patients - A randomized, double-blind, crossover, placebo-controlled study

    Jeppesen, P.B.; Szkudlarek, J.; Høy, Carl-Erik;

    2001-01-01

    Background: Positive effects of high dose growth hormone and glutamine (GH+GLN) on body composition in short bowel patients have been described. Lack of effects on intestinal absorption found in some studies has been ascribed to concomitant essential fatty acid (EFA) deficiency. This study...... hormone (mean, 0.12 mg/kg/day) plus oral (mean, 28 g/day) and parenteral glutamine (mean, 5.28/day) for 28 days. Body composition was measured by dual-energy absorptiometry (DEXA) scans. intestinal fatty acid absorption was evaluated in balance studies, and EFAs were measured in plasma phospholipids by...... index above 0.2, indicative of EFA deficiency. Air developed peripheral oedema. Conclusions: Combined high dose growth hormone and glutamine administered far 4 weeks, did not improve absorption of fatty acids or EFA status in short bowel patients. No changes in BW or composition were seen when comparing...

  20. Effect of phytohormones on absorption and distribution of ions in salt-stressed bean plants

    Zofia Starck

    2014-02-01

    Full Text Available Bean plant seedlings grown in water culture were treated for 5 days either with NaCl or with 7-times concentrated nutrient solution (diminished water potential by 3-103 hPa in both cases. Control and stressed plants were treated for 24 hrs with zeatin and GA,. NaCl-stress reduced distinctly ion absorption rate (K, Ca and P. Zeatin and GA3 promoted potassium uptake, but only in NaCI-treated plants. These hormones diminished Na accumulation in metabolically active organs but increased P- and Ca-content. In plants grown under both kind of stresses zeatin and GA3 partially reestablished the ratio of the main mono- to divalent cations, which increased in the leaves and apical part of the stressed plants. ABA introduced into the nutrient solution caused inhibition of the ion uptake (K, Ca, Mg and P. similar to that caused by NaCl-stress. The above reported results seem to confirm the supposition, that hormones act as an important factor contributing to regulation of both uptake and distribution of ions. In this way growth substances may also participate in the regulation of transport of various substances (among others - assimilates in the whole plant.

  1. Fertilizer N absorption and distribution by soybean from seedling to pod beginning

    The nitrogen assimilation and absorption by the soybean plant, especially the distribution of fertilizer N among different organs and nodes were studied during the period from seedling to pod beginning by using sand culture and staged 15N labeling method. Results were as follows: (1) total nitrogen accumulation during the five labeling experiments increased from 64.08 mg/plant in labeling experiment Ⅰ to 307.17 mg/plant in labeling experiment Ⅴ. (2) Fertilizer N accumulation in different organs exhibited different proportions during the period from seedling to pod beginning, with the highest in leaves (55.2%), 25.9% in roots and 18.9% in stems. (3) The accumulation and proportion of nodulations N increased gradually during the period from seedling to beginning, however for fertilizer N it was contrary, the soybean plant depended mainly on fertilizer-N before full bloom and then nodulations N during the period from full bloom to pod beginning. (4) Fertilizer N accumulation in leaves at different growing stages followed the order of growing leaves > newborn leaves > mature leaves. (5) Nitrogen composition of newborn leaves changed with that in total plant: fertilizer N was the primary nitrogen source from seedling to bloom beginning, and nodulations N was the primary nitrogen source from bloom beginning to pod beginning. (authors)

  2. Radio Through X-ray Spectral Energy Distributions of 38 Broad Absorption Line Quasars

    Gallagher, S C; Brandt, W N; Egami, E; Hines, D C; Priddey, R S

    2007-01-01

    We have compiled the largest sample of multiwavelength spectral energy distributions (SEDs) of Broad Absorption Line (BAL) quasars to date, from the radio to the X-ray. We present new Spitzer MIPS (24, 70, and 160 micron) observations of 38 BAL quasars in addition to data from the literature and public archives. In general, the mid-infrared properties of BAL quasars are consistent with those of non-BAL quasars of comparable luminosity. In particular, the optical-to-mid-infrared luminosity ratios of the two populations are indistinguishable. We also measure or place upper limits on the contribution of star formation to the far-infrared power. Of 22 (57%) upper limits, seven quasars have sufficiently sensitive constraints to conclude that star formation likely contributes little (<20%) to their far-infrared power. The 17 BAL quasars (45%) with detected excess far-infrared emission likely host hyperluminous starbursts with L_fir,SF=10^{13-14} L_sun. Mid-infrared through X-ray composite BAL quasar SEDs are pre...

  3. Remote sensing of vertical phytoplankton pigment distributions in the Baltic: new mathematical expressions. Part 3: Nonphotosynthetic pigment absorption factor:

    Bogdan Woźniak; Roman Majchrowski; Mirosława Ostrowska; Dariusz Ficek; Justyna Kunicka; Jerzy Dera

    2007-01-01

    This paper, part 3 of the description of vertical pigment distributions in the Baltic Sea, discusses the mathematical expression enabling the vertical distributions of the non-photosynthetic pigment absorption factor fa to be estimated. The factor fa is directly related to concentrations of the several groups of phytoplankton pigments and describes quantitatively the ratio of the light energy absorbed at given depths by photosynthetic pigments to the light energy absorbed by all the phytoplan...

  4. Reconstruction of combustion temperature and gas concentration distributions using line-of-sight tunable diode laser absorption spectroscopy

    Zhang, Zhirong; Sun, Pengshuai; Pang, Tao; Xia, Hua; Cui, Xiaojuan; Li, Zhe; Han, Luo; Wu, Bian; Wang, Yu; Sigrist, Markus W.; Dong, Fengzhong

    2016-07-01

    Spatial temperature and gas concentration distributions are crucial for combustion studies to characterize the combustion position and to evaluate the combustion regime and the released heat quantity. Optical computer tomography (CT) enables the reconstruction of temperature and gas concentration fields in a flame on the basis of line-of-sight tunable diode laser absorption spectroscopy (LOS-TDLAS). A pair of H2O absorption lines at wavelengths 1395.51 and 1395.69 nm is selected. Temperature and H2O concentration distributions for a flat flame furnace are calculated by superimposing two absorption peaks with a discrete algebraic iterative algorithm and a mathematical fitting algorithm. By comparison, direct absorption spectroscopy measurements agree well with the thermocouple measurements and yield a good correlation. The CT reconstruction data of different air-to-fuel ratio combustion conditions (incomplete combustion and full combustion) and three different types of burners (one, two, and three flat flame furnaces) demonstrate that TDLAS has the potential of short response time and enables real-time temperature and gas concentration distribution measurements for combustion diagnosis.

  5. Absorption and distribution of Zn by spring wheat in high zinc soil and effect of rhizosphere soil

    The isotope tracer technique was used to study the absorption and distribution of 65Zn by spring wheat in high zinc soil. The results showed that the distribution of 65Zn in the organs of spring wheat was in the order as stem leaf>grain>root>wheat husk; the specific activity of 65Zn and the transfer factor of 65Zn in the organs of spring wheat were in the order as root>grain>wheat husk>stem leaf. With added 65Zn increased, the absorption amount of 65Zn by spring wheat and the distribution of 65Zn in root increased. The 65Zn applied was enriched by rhizosphere soil of spring wheat

  6. Effects of heat stress on dynamic absorption process, tissue distribution and utilization efficiency of vitamin C in broilers

    The experiment was conducted to determine the effects of heat stress on ascorbic acid nutritional physiology of broilers with radioisotope technology. 3H-Vc was fed to broilers and then the blood, liver, kidney, breast muscle, and excreta were sampled to determine the dynamic absorption process, the tissue distribution and the utilization efficiency of vitamin C. The results indicated that the absorption, metabolism and mobilization of supplemented vitamin C in broilers with heat stress was faster than that in broilers without heat stress. However, the utilization efficiency of supplemented vitamin C in broilers with heat stress was not higher than that of broilers without heat stress

  7. Quantitation of phosphorus excretion in sheep by compartmental analysis

    The control of phosphorus excretion in sheep has been examined by constructing a kinetic model that contains a mechanistic set of connections between blood and gastrointestinal tract. The model was developed using experimental data from chaff-fed sheep and gives an accurate description of the absorption and excretion of 32P phosphorus in feces and urine of the ruminating sheep. These results indicated the main control site for phosphorus excretion in the ruminating sheep was the gastrointestinal tract, whereas for the non-ruminating sheep fed the liquid diet, control was exerted by the kidney. A critical factor in the induction of adaptation of phosphorus reabsorption by the kidney was the reduction in salivation, and since this response occurred independently of marked changes in the delivery of phosphorus to the kidney, a humoral factor may be involved in this communication between salivary gland and kidney

  8. Drug absorption from the irradiated rat small intestine in situ

    The absorption of acidic drugs phenobarbitone and sulphafurazole, basic drugs mecamylamine and quinidine, and a neutral drug isoniazid was studied in situ. Rats were irradiated 750 rad whole-body with 60Co and the absorption experiment was done three and six days thereafter using the cannulated small intestine of urethane-anaesthetized rats. Drug disappearance from the intestinal lumen and drug levels in the whole blood and intestinal wall were measured. In control rats phenobarbitone showed the most rapid absorption and mecamylamine the slowest. Irradiation retarded the disappearance of all drugs from the intestinal lumen on the third postirradiation day. Fluid absorption was also diminished. On the sixth postirradiation day the absorption of phenobarbitone, sulphafurazole and mecamylamine had returned to the control level, but the absorption of quinidine and isoniazid was still retarded. After i.v. administration of drugs they were not significantly excreted into the intestinal contents and irradiation did not modify excretion. The distribution of drugs between the intestinal fluid and the intestinal wall was complete in the first 10 min of experiment. Mecamylamine and quinidine were lowered in the whole blood by irradiation. Blood levels of drugs did not correlate well to the rate of disappearance of drugs from the intestinal lumen. The reversible changes in absorption induced by irradiation are probably secondary effects of irradiation on intestinal morphology, permeability and transport capacity, composition, and possibly blood flow. (orig.)

  9. Research on urinary excretion of purine derivatives in ruminants: Past, present and future

    Research on urinary excretion of purine derivatives (PD), namely allantoin, uric acid, xanthine and hypoxanthine, in ruminants have been carried out with an objective to use the excretion of these purine metabolites as a parameter to estimate the intestinal flow of microbial protein. This paper reviews the published literature, from the first paper in 1931 to the current date. The current status of understanding in some key topics is discussed. The topics include: endogenous excretion, modelling the response of PD excretion to purine absorption, calculation of microbial N supply from PD excretion, use of spot urine measurement, possible use of plasma or milk PD as an alterative index, and applications in ruminant nutrition research. This review also covers the current understanding of PD excretion in different animal species, including sheep, cattle, goats, buffaloes, llamas, camels, yak and deer. Progress in analytical methods for the determination of purine derivatives is also discussed. Finally, areas of future research are highlighted. The paper stresses the need for more studies on metabolism of PD in the tissue, the kinetics of PD in the blood and physiological processes of renal excretion, so as to understand better the mechanism that accounts for the between-species and within species variation in PD excretion. Development of simpler and more rapid methods for defining the endogenous excretion and purine input-output relationship is also an area for future work. (author)

  10. Residue strength, water absorption and pore size distributions of recycled aggregate concrete after exposure to elevated temperatures

    Kou, Shi-Cong; Poon, Chi-Sun; Etxeberria Larrañaga, Miren

    2014-01-01

    In this paper, the effects of high temperature exposure of recycled aggregate concretes in terms of residual strengths, capillary water absorption capacity and pore size distribution are discussed. Two mineral admixtures, fly ash (FA) and ground granulated blast furnace (GGBS) were used in the experiment to partially replace ordinary Portland cement for concrete production. The water to cementitious materials ratio was maintained at 0.50 for all the concrete mixes. The replacement levels of n...

  11. Optical imaging of absorption and distribution of RITC-SiO2 nanoparticles after oral administration

    Lee CM

    2014-12-01

    Full Text Available Chang-Moon Lee,1 Tai Kyoung Lee,2–5 Dae-Ik Kim,1,6 Yu-Ri Kim,7 Meyoung-Kon Kim,7 Hwan-Jeong Jeong,2–5 Myung-Hee Sohn,2–5 Seok Tae Lim2–5 1Department of Biomedical Engineering, Chonnam National University, Yeosu, Jeollanam-Do, Republic of Korea; 2Department of Nuclear Medicine, Chonbuk National University Medical School and Hospital, Jeonju, Jeollabuk-Do, Republic of Korea; 3Cyclotron Research Center, Chonbuk National University Medical School and Hospital, Jeonju, Jeollabuk-Do, Republic of Korea; 4Biomedical Research Institute, Chonbuk National University Medical School and Hospital, Jeonju, Jeollabuk-Do, Republic of Korea; 5Molecular Imaging and Therapeutic Medicine Research Center, Chonbuk National University Medical School and Hospital, Jeonju, Jeollabuk-Do, Republic of Korea; 6School of Electrical, Electronic Communication, and Computer Engineering, Chonnam National University, Yeosu, Jeollanam-Do, Republic of Korea; 7Department of Biochemistry and Molecular Biology, Korea University Medical School and College, Seounbuk-Gu, Seoul, Republic of Korea Purpose: In this study, we investigated the absorption and distribution of rhodamine B isothiocyanate (RITC-incorporated silica oxide nanoparticles(SiNPs (RITC-SiNPs after oral exposure, by conducting optical imaging, with a focus on tracking the movement of RITC-SiNPs of different particle size and surface charge. Methods: RITC-SiNPs (20 or 100 nm; positively or negatively charged were used to avoid the dissociation of a fluorescent dye from nanoparticles via spontaneous or enzyme-catalyzed reactions in vivo. The changes in the nanoparticle sizes and shapes were investigated in an HCl solution for 6 hours. RITC-SiNPs were orally administered to healthy nude mice at a dose of 100 mg/kg. Optical imaging studies were performed at 2, 4, and 6 hours after oral administration. The mice were sacrificed at 2, 4, 6, and 10 hours post-administration, and ex vivo imaging studies were performed

  12. Fiber-distributed multi-channel open-path H2S sensor based on tunable diode laser absorption spectroscopy

    Dong Chen; Wenqing Liu; Yujun Zhang; Jianguo Liu; Ruifeng Kan; Min Wang; Xi Fang; Yiben Cui

    2007-01-01

    Tunable diode laser based gas detectors are now being used in a wide variety of applications for safety and environmental interest. A fiber-distributed multi-channel open-path H2S sensor based on tunable diode laser absorption spectroscopy (TDLAS) is developed, the laser used is a telecommunication near infrared distributed feed-back (DFB) tunable diode laser, combining with wavelength modulation specby combining optical fiber technique. An on-board reference cell provides on-line sensor calibration and almost maintenance-free operation. The sensor is suitable for large area field H2S monitoring application.

  13. Hair chromium concentration and chromium excretion in tannery workers.

    Saner, G; Yüzbasiyan, V; Cigdem, S

    1984-01-01

    Hair and urine samples were collected from 34 male tannery workers and from 12 normal adults. Eighteen of the workers dealt directly with chromium and the remaining 16 (controls) worked in the offices and kitchen of the same factory. All were found to be clinically healthy. Chromium was determined by flameless atomic absorption spectroscopy. When compared with normal adult values, urinary chromium concentration, Cr/Creatinine ratio, daily chromium excretion, and hair chromium, concentrations ...

  14. Spatial and temporal variations in NO(2) distributions over Beijing, China measured by imaging differential optical absorption spectroscopy.

    Lee, Hanlim; Kim, Young J; Jung, Jinsang; Lee, Chulkyu; Heue, Klaus-Peter; Platt, Ulrich; Hu, Min; Zhu, Tong

    2009-04-01

    During the CAREBEIJING campaign in 2006, imaging differential optical absorption spectroscopy (I-DOAS) measurements were made from 08:00 to 16:00 on September 9 and 10 over Beijing, China. Detailed images of the near-surface NO(2) differential slant column density (DSCD) distribution over Beijing were obtained. Images with less than a 30-min temporal resolution showed both horizontal and vertical variations in NO(2) distributions. For DSCD to mixing ratio conversion, path length along the lines of I-DOAS lines of sight was estimated using the light-extinction coefficient and Angstrom exponent data obtained by a transmissometer and a sunphotometer, respectively. Mixing ratios measured by an in-situ NO(2) analyzer were compared with those estimated by the I-DOAS instrument. The obtained temporal and spatial variations in NO(2) distributions measured by I-DOAS for the two days are interpreted with consideration of the locations of the major NO(x) sources and local wind conditions. I-DOAS measurements have been applied in this study for estimating NO(2) distribution over an urban area with multiple and distributed emission sources. Results are obtained for estimated temporal and spatial NO(2) distributions over the urban atmosphere; demonstrating the capability of the I-DOAS technique. We discuss in this paper the use of I-DOAS measurements to estimate the NO(2) distribution over an urban area with multiple distributed emission sources. PMID:19111964

  15. A measurement plan of gas concentration and temperature distribution reconstruction based on the tunable diode laser absorption tomography

    Liu, Zhao-ran; Jin, Xing; Wang, Guang-yu; Song, Jun-ling

    2014-11-01

    Based on the tunable diode laser absorption tomography, gas concentration and temperature two-dimensional distribution reconstruction is realized using algebraic iterative reconstruction technique (ART). A measurement plan is proposed based on the beam splitting lens, and the corresponding beam arrangement is put forward. The beam splitting lenses are used in the plan to making one laser beam cross the measurement area repeatedly. Thus can raise the utilization ratio of laser beam and simplify the structure of measurement platform. A model for H2O vapor concentration and temperature distribution is assumed, and numerical simulation is utilized using two absorption transitions. The feasibility of the measurement plan is proved by the simulation experiment. The influences of initial beam angle, the number of beams and grids on the reconstructed results are analyzed numerically. A concept of phantom description method using in simulation experiments is proposed in order to getting closer to the real experiments. The phantom description method is used in the numerical simulation to evaluating concentration and temperature field reconstruction. Through this method, expected data is sampled from initial data, and reconstructed result is obtained by interpolation. The influence of random errors in projections on distribution reconstruction is also analyzed. The measurement plan can reconstruct the gas concentration and temperature distribution with a simplified measurement platform using beam splitting lenses. The feasibility of the phantom description method is also proved by the simulation experiment.

  16. Updated correlation of the absorption line blackbody distribution function for H2O based on the HITEMP2010 database

    The absorption line blackbody distribution function (ALBDF) was developed for use in global methods such as the SLW and FSK models that integrate the radiative transfer equation over the absorption coefficient rather than wavenumber. A widely used method of representing the ALBDF efficiently is a correlation in the form of a hyperbolic tangent function originally proposed by Denison and Webb. This paper reports on the generation of new coefficients to be used in the correlation for H2O using the recently released high temperature database, HITEMP2010. The updated correlation is valid for an expanded temperature range, from 400 to 3000 K, made possible by the new database. The accuracy of the new coefficients is tested and compared against the previous correlations through calculations of total emissivity and the Planck mean absorption coefficient. Solutions of the radiative transfer equation in homogeneous one-dimensional media have been performed with the SLW method using the updated ALBDF, and are compared to rigorous line-by-line calculations. The updated correlation performs very well in these calculations and shows excellent accuracy compared to the line-by-line benchmark predictions. Comparisons made with the previous coefficients show that updating the correlation was necessary in order to obtain accurate calculations. -- Highlights: ► HITEMP2010 was used to update the absorption line blackbody distribution function. ► Hyperbolic tangent form used previously was maintained. ► Temperature ceiling was extended from 2500 K up to 3000 K. ► Calculations using the updated correlation demonstrate its accuracy. ► Comparisons with the previous correlation demonstrate the need for an update

  17. Effect of quantum dot size and size distribution on the intersublevel transitions and absorption coefficients of III-V semiconductor quantum dot

    The intersublevel absorption peak energy and absorption coefficient of non-uniform quantum dot (QD) ensembles are calculated analytically. The effect of size variations and size distribution of QDs on their energy states is analyzed. The dots are considered as a quantum box with finite potential at the barriers and the size distribution described by a Gaussian function. The influence of the aspect ratio (base to height ratio) of the QDs on the optical transitions is studied. Our model predicts the dot size (height and base) accurately to determine the absorption peaks and corresponding absorption coefficient. We also compute the absorption coefficient of the QD with different size distributions to verify the results calculated using this model with the reported experimental and other theoretical results

  18. Principles and approaches to increasing radionuclide excretion from human organism under chronical intake

    The main principles for increasing natural excretion of radioactive substances incorporated by a man are suggested. These are decreasing radionuclide intakes with food, water and phlegm, as well as their absorption from digestion tract. It is suggested to use specific compounds binding individual radionuclides (salt of alginic acid, ferrocene), nonspecific entersorbents (vegetable cellulose; substances containing pectin; carbonaceous sorbent); to enhance radionuclide excretions from places of deposition into blood and later into gastrointestinal tract, urination system, perspiration system. 13 refs

  19. The absorption, utilization and distribution of nitrate 15N and ammonium 15N in Populus Tomentosa seedlings

    Effects of different nitrogen sources (NO3-, NH4+) on the absorption, distribution and utilization of nitrogen on Populus tenement's seedlings (clone 50) was studied by using the 15N trace technique. Results showed that the Populus tenement's seedlings had the same nitrogen take up pattern: tissue nitrogen content grew up after fertilization, remarkbaly rising up after one week and reached peak after 28 days. Although the treatments are different, the tissue N content was about the same between 0.6g · plant-1. The maximum absorption of NO3-15N and NH4-15N was 0.26g · plant-1 and 0.12g · plant -1, which accounted for 39.15% and 19.95% of total nitrogen, respectively. The nitrogen use efficiency (NUE) of two nitrogen sources varied gignificantly. The maximum NUE of NO3-15N reached 25.83%, nearly twice of that of NH4-15N (12.03%). Hence we conclude that Populus tomentosa seedlings (clone 50) prefer to absorb NO3-. Nitrogen distribution rate changed obviously among different organs and the trend was leaf>root>stem. In the leaf, the distribution of NO3-15N was higher than that of NH4-15N. (authors)

  20. Biliary excretion of chromium in the rat

    The relative amount of chromium excreted in rat bile after injection of Cr-III is much less than after injection of Cr-VI, about 0.1% and from 6-8% during 5 hours respectively, for corresponding dose levels. The liver to bile ratio was 50-100 for Cr-III injection for Cr-VI the ratio was 2-3. With doses up to 18 μmol Cr/kg, only Cr-III was found in bile even after injection of CR-VI.Glutathione depletion of the liver with cyclohexene oxide decreased chromium excretion in bile. Such treatment also decresed the reduction of Cr-VI to Cr-III in the liver cell as only Cr-VI was found in bile. A different distribution of Cr-III in the liver dependent on whether derived from Cr-VI or taken up by the liver as such must be assumed. Taking into account the usual low penetration of biological membranes by Cr-III, a possible active transport mechanism or a specific diffusable Cr-III compound must be postulated. (author)

  1. A one-dimensional, one-group absorption-production nodal method for neutron flux and power distributions calculations

    It is presented the absorption-production nodal method for steady and dynamical calculations in one-dimension and one group energy. It was elaborated the NOD1D computer code (in FORTRAN-IV language). Calculations of neutron flux and power distributions, burnup, effective multiplication factors and critical boron concentration were made with the NOD1D code and compared with results obtained through the CITATION code, which uses the finite difference method. The nuclear constants were produced by the LEOPARD code. (M.C.K.)

  2. The absorption, distribution, metabolism and elimination of β-(p-chlorophenyl)-GABA (Baclofen), 4

    Distribution of 14C-baclofen was studied according to the autoradiography of a whole body in SD-JCL male rats after oral administration of 14C-baclofen (100 μCi/kg). Distribution of radioactivity in kidney and liver was already apparent 15 min after administration. Radioactivity in kidney and liver was increased distribution of radioactivity in skeletal muscle was apparent 1 hr after administration. Radio and activity in various tissues decreased 3 hrs after administration. Distribution of radioactivity in brain and spinal cord remained low at any time after administration. Distribution of radioactivity of 14C-baclofen in autoradiography was consistent with that in tracer study (Yamamoto et al 1977). (auth.)

  3. SYNCHROTRON POLARIZATION AND SYNCHROTRON SELF-ABSORPTION SPECTRA FOR A POWER-LAW PARTICLE DISTRIBUTION WITH FINITE ENERGY RANGE

    We have derived asymptotic forms for the degree of polarization of the optically thin synchrotron and for synchrotron self-absorption (SSA) spectra assuming a power-law particle distribution of the form N(γ) ∼ γ–p with γ1 2, especially for a finite high-energy limit, γ2, in the case of an arbitrary pitch angle. The new results inferred concern more especially the high-frequency range x >> η2 with parameter η = γ2/γ1. The calculated SSA spectra concern instantaneous photon emission where cooling effects are not considered. They have been obtained by also ignoring likely effects such as Comptonization, pair creation and annihilation, as well as magnetic photon splitting. To that aim, in addition to the two usual absorption frequencies, a third possible one has been derived and expressed in terms of the Lambert W function based on the analytical asymptotic form of the absorption coefficient, αν, for the high-frequency range ν >> ν2 (with ν2 the synchrotron frequency corresponding to γ2). We have shown that the latter frequency may not have realistic applications in astrophysics, except in the case of an adequate set of parameters allowing one to neglect Comptonization effects. More detailed calculations and discussions are presented.

  4. Uptake, retention and excretion of strontium in man

    The absorption of strontium from the gastrointestinal tract is discussed in relation to the diet and the different components of a bread-milk diet. A brief review is given of the results obtained by using chelators and diets high in calcium in order to decrease the strontium absorption. The ratios of strontium to calcium in the different body compartments for adult man is discussed. The results of recent experimental work on normal man on a constant diet, are reviewed with particular reference to the urinary excretion and the retention of Sr85 contained in the experimental diet. The endogenous faecal excretion is also derived. These results are compared with those obtained from a single intravenous injection of radioactive strontium. For all the subjects the retention was obtained from whole-body counting using a pulse height analyser. The retention of the strontium in the skeleton is analysed and it is postulated that there are at least three degrees of binding of radioactive strontium with bone. In particular the retention several months after the dose and the relationship of this retention to the radiation dose to the skeleton from Sr90 is discussed. A formula is proposed for the evaluation of body retention of a radioactive dose of strontium from the radioactivity excreted in the urine. (author)

  5. Phosphate absorption and distribution in flue-cured tobacco under different ozone consistency by using 32P

    The absorption and distribution of phosphate in flue-cured tobacco under different ozone consistencies was studied by using 32P. The results showed that the percentage of root of whole tobacco plant assimilating 32p reduced as growing, but in stem it increased as growing in the sand culture. Root and stem of flue-cured tobacco assimilating 32P varied little in the whole growing period in the solution culture. Distribution situation in leaf with two consistencies was in the order of lower leaf>cutters leaf>upper leaf, and the ratio of radioactivity showed root>stem>lower leaf>cutters leaf>upper leaf. However, flue-cured tobacco assimilating phosphate in the two consistencies showed significantly positive correlation with length of growth period. Assimilating phosphate in the solution culture was more and faster than in the low ozone consistency culture

  6. Do changes in the azimuthal distribution of maize leaves over time affect canopy light absorption?

    Drouet, J.L.; Moulia, B.; Bonhomme, R

    1999-01-01

    Pour les couverts de maïs, les modèles d’architecture des plantes et de transferts radiatifs utilisent classiquement l’hypothèse d’une répartition aléatoire des feuilles en azimut. Ayant précédemment mis en évidence des ré-orientations azimutales des feuilles de maïs au cours de la phase végétative, nous avons testé le poids de cette hypothèse sur l’absorption journalière de lumière par le couvert. Pour cela, nous avons modélisé la géométrie en trois dimensions (3D) de couverts de maïs de den...

  7. Effective utilization of quantum-cascade distributed-feedback lasers in absorption spectroscopy

    Kosterev, A. A.; Curl, R. F.; Tittel, F. K.; Gmachl, C.; Capasso, F.; Sivco, D. L.; Baillargeon, J. N.; Hutchinson, A. L.; Cho, A. Y.

    2000-01-01

    A variable duty cycle quasi-cw frequency scanning technique was applied to reduce thermal effects resulting from the high heat dissipation of type I quantum-cascade lasers. This technique was combined with a 100-m path-length multipass cell and a zero-air background-subtraction technique to enhance detection sensitivity to a parts-in-10(9) (ppb) concentration level for spectroscopic trace-gas detection of CH4, N2O, H2O, and C2H5OH in ambient air at 7.9 micrometers. A new technique for analysis of dense high resolution absorption spectra was applied to detection of ethanol in ambient air, yielding a 125-ppb detection limit.

  8. Kidney Modelling for FDG Excretion with PET

    Huiting Qiao

    2007-07-01

    Full Text Available The purpose of this study was to detect the physiological process of FDG's filtration from blood to urine and to establish a mathematical model to describe the process. Dynamic positron emission tomography scan for FDG was performed on seven normal volunteers. The filtration process in kidney can be seen in the sequential images of each study. Variational distribution of FDG in kidney can be detected in dynamic data. According to the structure and function, kidney is divided into parenchyma and pelvis. A unidirectional three-compartment model is proposed to describe the renal function in FDG excretion. The time-activity curves that were picked up from the parenchyma, pelvis, and abdominal aorta were used to estimate the parameter of the model. The output of the model has fitted well with the original curve from dynamic data.

  9. The absorption distribution and utilization of N in different nitrogen forms by american ginsengs

    NH4+ and NO3- uptake by 2,3,4-year old Panax quinquefolium and their distribution in the plants were studied with 15N tracer in both soil and water cultures. The results showed that P. quinquefolium can absorb both NH4+ and NO3- from sprouting stage to leaf expansion stage, but the absorbing capacity for NH4+ was twice as that for NO3-, and during this period more fertilizer was distributed in stem and leaves than in roots. During the stage of root growth, however, the plants absorbed the both forms of fertilizer well, and more fertilizer was distributed in root than in stem and leaves. Of the total nitrogen content absorbed by P. quinquefolium cultured in soil, more than 80% was from soil, about 5% was from fertilizer, and the rest was from original root. It is concluded that improving fertility of soil and culturing strong root are keys to improve yield and quality of P. quinquefolium

  10. Aerosol particle number size distributions and particulate light absorption at the ZOTTO tall tower (Siberia), 2006-2009

    Heintzenberg, J.; Birmili, W.; Otto, R.; Andreae, M. O.; Mayer, J.-C.; Chi, X.; Panov, A.

    2011-08-01

    This paper analyses aerosol particle number size distributions, particulate absorption at 570 nm wavelength and carbon monoxide (CO) measured between September 2006 and January 2010 at heights of 50 and 300 m at the Zotino Tall Tower Facility (ZOTTO) in Siberia (60.8° N; 89.35° E). Average number, surface and volume concentrations are broadly comparable to former studies covering shorter observation periods. Fits of multiple lognormal distributions yielded three maxima in probability distribution of geometric mean diameters in the Aitken and accumulation size range and a possible secondary maximum in the nucleation size range below 25 nm. The seasonal cycle of particulate absorption shows maximum concentrations in high winter (December) and minimum concentrations in mid-summer (July). The 90th percentile, however, indicates a secondary maximum in July/August that is likely related to forest fires. The strongly combustion derived CO shows a single winter maximum and a late summer minimum, albeit with a considerably smaller seasonal swing than the particle data due to its longer atmospheric lifetime. Total volume and even more so total number show a more complex seasonal variation with maxima in winter, spring, and summer. A cluster analysis of back trajectories and vertical profiles of the pseudo-potential temperature yielded ten clusters with three levels of particle number concentration: Low concentrations in Arctic air masses (400-500 cm-3), mid-level concentrations for zonally advected air masses from westerly directions between 55° and 65° N (600-800 cm-3), and high concentrations for air masses advected from the belt of industrial and population centers in Siberia and Kazakhstan (1200 cm-3). The observational data is representative for large parts of the troposphere over Siberia and might be particularly useful for the validation of global aerosol transport models.

  11. Toxic metals distribution in different components of Pakistani and imported cigarettes by electrothermal atomic absorption spectrometer.

    Kazi, T G; Jalbani, N; Arain, M B; Jamali, M K; Afridi, H I; Sarfraz, R A; Shah, A Q

    2009-04-15

    It was extensively investigated that a significant flux of toxic metals, along with other toxins, reaches the lungs through smoking. In present study toxic metals (TMs) (Al, Cd, Ni and Pb) were determined in different components of Pakistani local branded and imported cigarettes, including filler tobacco (FT), filter (before and after normal smoking by a single volunteer) and ash by electrothermal atomic absorption spectrometer (ETAAS). Microwave-assisted digestion method was employed. The validity and accuracy of methodology were checked by using certified sample of Virginia tobacco leaves (ICHTJ-cta-VTL-2). The percentages (%) of TMs in different components of cigarette were calculated with respect to their total contents in FT of all branded cigarettes before smoking, while smoke concentration has been calculated by subtracting the filter and ash contents from the filler tobacco content of each branded cigarette. The highest percentage (%) of Al was observed in ash of all cigarettes, with range 97.3-99.0%, while in the case of Cd, a reverse behaviour was observed, as a range of 15.0-31.3% of total contents were left in the ash of all branded cigarettes understudy. PMID:18657905

  12. Toxic metals distribution in different components of Pakistani and imported cigarettes by electrothermal atomic absorption spectrometer

    It was extensively investigated that a significant flux of toxic metals, along with other toxins, reaches the lungs through smoking. In present study toxic metals (TMs) (Al, Cd, Ni and Pb) were determined in different components of Pakistani local branded and imported cigarettes, including filler tobacco (FT), filter (before and after normal smoking by a single volunteer) and ash by electrothermal atomic absorption spectrometer (ETAAS). Microwave-assisted digestion method was employed. The validity and accuracy of methodology were checked by using certified sample of Virginia tobacco leaves (ICHTJ-cta-VTL-2). The percentages (%) of TMs in different components of cigarette were calculated with respect to their total contents in FT of all branded cigarettes before smoking, while smoke concentration has been calculated by subtracting the filter and ash contents from the filler tobacco content of each branded cigarette. The highest percentage (%) of Al was observed in ash of all cigarettes, with range 97.3-99.0%, while in the case of Cd, a reverse behaviour was observed, as a range of 15.0-31.3% of total contents were left in the ash of all branded cigarettes understudy

  13. Absorption, distribution and utilization of radioactive phosphorus in healthy and root (wilt) diseased coconut palms

    Radioactive KH2P32O4 was fed to coconut leaves and palms under laboratory and field conditions. In healthy palms the absorption of phosphorus by roots and its accumulation in spindle and first fully opened leaves was found to be significantly higher till 9th hr as compared to that of diseased palms, but at later stages the reverse pattern was observed. The time required for 32P to reach the spindle (top-most leaf) situated at 9.5 m height in both diseased and healthy palm was found to be 3 hr only. In contrast to the leaves, the activity of 32P differed insignificantly in stem and roots of healthy and diseased palms and also the native P remained higher in the stem and roots of former palms as compared to latter. The analysis of total different fractions of phosphorus and entry of 32P in the different forms of organic phosphorus indicated that although total P was more in the case of diseased palms but the organic phosphorus especially the nucleic acid P was significantly less as compared to healthy ones. This revealed less utilization of absorbed P in the synthesis of P-constituted organic substances in diseased palms. (auth.)

  14. Enhancement of radiopharmaceutical excretion by chemical interventions

    It was shown previously that desferrioxamine (DFO) enhances urinary excretion of Ga-67. The present study is an extension of these observations to other compounds that may enhance the excretion of Tc-99m pertechnetate (Tc), Ga-67 citrate (Ga) and Tl-201 chloride (Tl). The purpose of these studies was to find methods of decreasing the radiation dose after radionuclide studies, by giving a compound that will increase the rate of excretion of the radionuclide

  15. Faecal excretion dynamic during subacute oral exposure to different Pb species in Rattus norvegicus.

    Cadková, Zuzana; Száková, Jiřina; Miholová, Daniela; Válek, Petr; Pacáková, Zuzana; Vadlejch, Jaroslav; Langrová, Iva; Jankovská, Ivana

    2013-05-01

    Faecal excretion is a basic means of detoxification upon ingestion of Pb-contaminated feed. In order to determine a time course of Pb elimination after oral exposure to two different forms of this heavy metal (lead acetate vs. phyto-bound Pb), a feeding study was carried out in experimental rats using the Pb phyto-hyperaccumulator Pistia stratiotes as a model diet. The effect of starvation on Pb excretion was further studied in rats that were fed plant material. Twelve Pb doses (7 μg Pb/1 g BW) were administered orally over a 5-week period. Faeces samples were collected 24 and 72 h post-exposure. Inductively coupled plasma optical emission spectrometry and electrothermal absorption spectrometry methods were used for determination of heavy metal concentrations. Up to 53 % of ingested Pb was rapidly eliminated from the exposed rats via faeces within 24 h after exposure. Faecal excretion in exposed rats differed significantly when compared to that of the control group. Fasting before exposure reduced Pb excretion by up to 50 %. Faecal excretions of both examined Pb forms exhibited almost identical patterns. Considerable differences were revealed concerning total excretion levels; lead acetate was excreted in amount greater extent than those of phytobound Pb. Results of our study suggest that Pb forms occurring in the P. stratiotes tissues are absorbed through the gastrointestinal tract to a greater extent than Pb from lead acetate. Therefore, higher portions of ingested Pb can be available for potential accumulation in tissues of exposed subjects. PMID:23408261

  16. Luminescent liposome labeling technology with PKH-26 solution and absorption and distribution assessment of lipid multilammelar vesicles and small liposomes in liver following intravenous administration

    This study examined the possibility to form liposomal compositions containing PKH-26 fluorescent dye and to use those compositions in order to assess absorption and tissue distribution of the liposomes in rat liver. Liposomal compositions consisted of egg lecithin and cholesterol (Sigma) in a 7:5 ratio, respectively. The dye was incorporated into the lipid layer while preparing multilammelar vesicles with the extruder. The obtained labeled liposomal compositions allowed to quantitatively assess how the vesicles are absorbed by the liver and visualize the dye distribution in different liver cells. The study presents the data on the absorption and distribution of the dye in the liver, according to the size of the lipid vesicles, 1, 2 and 24 hours after the intravenous administration. Key words : luminescent labeling, absorption of the liposomes, visualization of the liposomes, liposomal distribution in the cells, PKH -26, liver

  17. Urinary excretion of purine derivatives in Yerli Kara cattle

    The urinary excretion of purine derivatives (PD) was measured in four Yerli Kara bulls in two experiments, a fasting experiment lasting for 7 days and the other , where animals were given a diet containing 30% wheat straw and 70% compounded feed at four levels of intake (40,60,80 and 95% of voluntary feed intake). In the second experiment, which was carried out according to a 4x4 Latin Square design, four animals receiving 60 and 95% levels of intake were also given a single injection of 8- ''1''4C - uric acid via a jugular catheter. In Addition to the above two experiments the activity of xanthine oxidase and uricase in plasma, liver and intestinal mucosa obtained from Yerli Kara cattle was also determined.In the first experiment,fasting PD excretion averaged 0.691 (±0.053) mmol/kgW''0''.''7''5/d. Glomerular filtration rate GFR), tubular load and net re-absorption of allantoin between pre fasting and fasting were statistically significant (P<0.05). In the second experiment the recovery of injected 8 - ''1''4C - uric acid as total PD was 72.5 and 89.9% for 60 and 95% feeding levels, respectively. The average recovery was 81%. Plasma kinetics measured by 8 - ''1''4C - uric acid indicated that the total compartment pool size was 214.0 (±43.8) and 250.3 L (±29.5) for 60 and 95% feeding levels, respectively. GFR, tubular load and net re-absorption of uric acid and allantoin were not affected by feed intake. The allantoin : PD molar ratios changed between 0.78 to 0.93 for the four levels feed intake. There were significant correlations between PD excretion (expressed as mmol/d and μmol/kg W''0''.''7''5/d) and DDMI (kg/d and kg/kg W''0''.''7''5/d) and DOMI (kg/d)(r=0.99, P<0.01). The rate of PD excretion as a linear function of feed intake was 16.4 mmol/kg W''0''.''7''5 DDMI, 19.8 mmol/kg DDMI and 22.7 mmol/kg DOMI. Xanthine oxidase and uricase activities were; 1.34 (±0.72) and .44 (±0.05) and 0.13 (±0.03) and 0.08 (±0.03) unit/g fresh tissue in liver and

  18. [Studies on the remote measurement of the distribution of city gaseous pollutant by mobile passive differential optical absorption spectroscopy].

    Wu, Feng-cheng; Li, Ang; Xie, Pin-hua; Xu, Jin; Shi, Peng; Qin, Min; Wang, Man-hua; Wang, Jie; Zhang, Yong

    2011-03-01

    An optical remote sensing method based on passive differential optical absorption spectroscopy for the measurement of the distribution of city gaseous pollutant was studied. The passive DOAS system, which was installed in a car, successively measures the interested area (such as city, industrial area) and the column density was obtained by DOAS fitting process using the zenith scattered sunlight. The mobile DOAS was applied to measurement in Shenzhen City during the continuous six days and got the distribution of SO2, NO2 in this paper. It showed that the pollution in the west is higher than in the east. The average concentration in the west is 2.0 times higher than the eastern for SO2 and 3.6 times for NO2. And comparison of the values between mobile DOAS and the point instrument was carried out in Baguang site. There was an agreement between the two instruments, the correlation coefficient was 0.86 for SO2, while 0.57 for NO2. The results indicate that this optical remote sensing method based on passive DOAS is an effective means of rapidly determining the distribution of city gaseous pollutant. PMID:21595196

  19. Investigations on temperature distribution of satellite surfaces affected by solar absorptivity

    Liu, Y.; Pan, X. X.; Li, G. H.; Liu, X.; Jiang, L. X.

    2010-09-01

    Based on the Monte Carlo ray-tracing method, the network coefficients of thermal network model describing the radiation heat transfer among satellite surfaces is solved by considering the surface material optical characters. It is superiority to the conventional Gebhart's method in view of the grey body and the diffuse reflection assumptions. The zone leveling method is used to discrete the governing equations and the solar absorpivity is separated and considered to be an important correction parameter. Effects of the solar incidence round angle, the zenith angle and the ratio of absorpivity to emissivity (RAE) on temperature distribution are numerically simulated and discussed in detail. The higher or the lower the RAE may be lead to the alternative heating and cooling tend with a larger heating or cooling velocity of main body surfaces than the solar array surfaces. Furthermore, maximum temperature of main body is almost larger than solar arrays. Under the same RAE, solar incidence angle make a great effect on the uniform character of temperature distribution.

  20. Absorption, distribution and utilization of soil-applied 10B in apple trees

    10B utilization rate was 7.0% and 10B distribution rate in roots, trunks and newly emerged organs of pot cultured apple tree (cv. 'liao fu'/Malus ptunifolia Borkh.) was 24.4%, 46.6% and 29.0%, respectively, in one month after soil-application of 10B during shoot rapid growth period. As the aerial newly emerged organs were concerned, Bdff% in long shoots and its leaves were higher than that in other shoots and leaves, suggesting that long shoots and its leaves had stronger ability of up taking 10B. At beginning of boron application, total boron amount and Bdff% in leaves increased fast, but 10B accumulating speed in shoot, particularly in its cortex, was higher than that in leaves in the later growing season, indicating that distribution center changed with growing period. The reserved boron in root and trunk played a mediative role in boron supply to newly emerged organs, a part of reserved mobile boron could transport to newly emerged organs when roots could not absorb any boron. With soil-applied 10B of 2μg·g-1 in autumn, Bdff% in soil was found less than 5% in the spring of the third year, but Bdff% in newly emerged organs was still 20%∼30%, which suggested that a part of reserved 10B could be reused

  1. Effects of the soil aeration on nutrient absorption, 14C-assimilates distribution and storage root yield in sweet potato

    Using Ipomoea batatas (L.) Lam. cv Lushu7 and Xushu18 as materials, the effect of the soil aeration on mineral nutrition absorption, 14C-assimilates distribution in storage roots and storage root yield were studied. The results showed that the improved soil aeration could increase the content of potassium, calcium, manganese, boron and zinc in leaves, increase the content of potassium and calcium in storage roots, decrease the content of manganese, boron and zinc in storage roots, improve the transportation of 14C-assimilates, increase the starch content of storage roots and significantly increase the storage root yield. The role of mineral elements on improving the transportation of 14C-assimilates was discussed

  2. A study of the absorption and distribution of isotope-labelling tracer 65Zn in Typha latifolia

    The result of the study of the absorption and distribution of 65Zn in Typha latifoliate shows that Typha has a very powerful capacity of absorbing 65Zn. The 65Zn absorbed and accumulated by the root and rhizome of Typha was much greater than that transferred to the leaf. The capacity of absorbing 65Zn of the organs of Typha is as follows: root>rhizome>leaf. The research also shows that the quantity of 65Zn absorbed by Typha increased with the time. Moreover, the quantity of zinc absorbed by Typha increased with the concentration of 65Zn in the culture solution. But the rate of absorbing 65Zn of Typha declined after 24 hor for the concentration of 65Zn in culture solution beyond 200 mg·kg-1

  3. Biliary excretion of iron and ferritin in idiopathic hemochromatosis

    The role of biliary excretion of iron and ferritin in iron overload was studied and evaluated. Ten patients with idiopathic hemochromatosis and two groups of controls (14 gallstone patients and 16 healthy subjects) were included. Liver tissue (obtained by percutaneous or operative biopsy) was investigated with light microscopy and transmission electron microscopy in combination with x-ray microanalysis. Fasting bile samples were obtained through duodenal aspiration or at cholecystectomy. Iron was determined in liver tissue and bile using atomic absorption spectroscopy, and ferritin was determined in serum and bile with a radioimmunoassay technique. All patients with hemochromatosis had iron-positive staining as seen in light microscopy. Electron microscopy showed iron-containing proteins in the lysosomes and cytosol of liver parenchymal cells, and this observation was supported by x-ray microanalysis. Hepatic iron concentration was increased about eightfold in the patients with hemochromatosis (p less than 0.001). Biliary iron concentration, expressed per millimole of bile acid, was increased about twofold (p less than 0.05) and biliary ferritin concentration about fivefold (p less than 0.001) in hemochromatosis. Four of the patients with hemochromatosis were reexamined after completed treatment with venesection; this resulted in normalized biliary concentrations of iron and ferritin. We conclude that biliary secretion of ferritin occurs in humans and that both iron and ferritin excretion are enhanced in hepatic iron overload. The apparently limited capacity of biliary iron excretion may be of importance for the hepatic iron accumulation in hemochromatosis

  4. Excretion of Four Catechins in Tea Polyphenols in Rats

    2009-01-01

    Objective To investigate excretion profiles of the four major anti-oxidant active catechins, (-) epigallo-catechin-3-gallate (EGCG), (-) epicatechin-3-gallate (ECG), (-) epigallocatechin (EGC), and epicatechin (EC) in tea polyphenols (TP) in rats in order to provide experimental data for clinical uses and development of TP as a novel drug. Methods The above four catechins in urine, bile, and feces were simultaneously determined by high performance liquid chromatography coupled with ultraviolet absorption detector (HPLC-UV) assay with a binary gradient elution. The samples were extracted by ethyl acetate prior to HPLC. The quantification was carried out by peak area internal standard method. Following iv dosing TP 100 mg/kg to rats, the samples were collected at different time intervals up to 8 h (urine and bile) and 24 h (feces). Results The urinary Ae, 0-8 h (cumulative excretion amount over 8 h) of EGCG, ECG, EGC, and EC were, on the average, 150.83, 30.75, 116.69, and 254.56 μg, corresponding to fe, 0-8 h (cumulative excretion fraction of dose over 8 h) of 1.45%, 0.84%, 7.88%, and 10.73%, respectively; the biliary Ae, 0-8 h were 12.61, 42.64, 6.61, and 1.24 μg, corresponding to the fe, 0-8 h of 0.12%, 1.16%, 0.45%, and 0.053%,respectively. For fecal excretion, only EGCG and EGC were detected with Ae, 0-24 h of 7.38 μg (fe, 0-24 h of 0.07%) and 157 μg (fe, 0-24 h of 9.99 %), respectively. The fe, total (the total fe of 3 excretory routes) were 18.32%, 10.78%, 2.00%, and 1.64% for EGC, EC, ECG, and EGCG, respectively. Conclusion EGCG and EC are mainly excreted in urine, ECG in bile, and EGC in feces by reference to their Ae and fe. The excretion of the four catechins based on fe, total is ranked in order of EGC > EC > ECG > EGCG. Only small amount of four catechins are recovered in urine, bile, and feces, indicating an extensive metabolic conversion of catechins in the rat body.

  5. Fast spatially resolved exhaust gas recirculation (EGR) distribution measurements in an internal combustion engine using absorption spectroscopy.

    Yoo, Jihyung; Prikhodko, Vitaly; Parks, James E; Perfetto, Anthony; Geckler, Sam; Partridge, William P

    2015-09-01

    Exhaust gas recirculation (EGR) in internal combustion engines is an effective method of reducing NOx emissions while improving efficiency. However, insufficient mixing between fresh air and exhaust gas can lead to cycle-to-cycle and cylinder-to-cylinder non-uniform charge gas mixtures of a multi-cylinder engine, which can in turn reduce engine performance and efficiency. A sensor packaged into a compact probe was designed, built and applied to measure spatiotemporal EGR distributions in the intake manifold of an operating engine. The probe promotes the development of more efficient and higher-performance engines by resolving high-speed in situ CO2 concentration at various locations in the intake manifold. The study employed mid-infrared light sources tuned to an absorption band of CO2 near 4.3 μm, an industry standard species for determining EGR fraction. The calibrated probe was used to map spatial EGR distributions in an intake manifold with high accuracy and monitor cycle-resolved cylinder-specific EGR fluctuations at a rate of up to 1 kHz. PMID:26253286

  6. Remote sensing of vertical phytoplankton pigment distributions in the Baltic: new mathematical expressions. Part 3: Nonphotosynthetic pigment absorption factor:

    Bogdan Woźniak

    2007-12-01

    Full Text Available This paper, part 3 of the description of vertical pigment distributions in the Baltic Sea, discusses the mathematical expression enabling the vertical distributions of the non-photosynthetic pigment absorption factor fa to be estimated. The factor fa is directly related to concentrations of the several groups of phytoplankton pigments and describes quantitatively the ratio of the light energy absorbed at given depths by photosynthetic pigments to the light energy absorbed by all the phytoplankton pigments together (photosynthetic and photoprotecting. Knowledge of this factor is highly desirable in the construction of state-of-the-art "light-photosynthesis" models for remote-sensing purposes.    The expression enables fa to be estimated with considerable precision on the basis of two surface parameters (available from satellite observations: the total chlorophyll a concentration at the surfaceCa(0 and the spectral downward irradiance Ed(λ, 0 just below the sea surface. The expression is applicable to Baltic waters from the surface down to an optical depth of τ ≈ 5.    The verification of the model description of fa was based on 400 quasi-empirical values of this factor which were calculated on the basis of empirical values of the following parameters measured at the same depths: Ed(λ, z (or also PAR(z, apl(λ, z,and the concentrations of all the groups of phytoplankton pigments Ca(z and Cj(z (where j denotes in turn chl b, chl c, PSC, phyc, PPC. The verification shows that the errors in the values of the non-photosynthetic pigment absorption factor fa estimated using the modeldeveloped in this work are small: in practice they do not exceed 4%.    Besides the mathematical description of the vertical distribution of fa, this paper also discusses the range of variation of its values measured in the Baltic and its dependence on the trophic index of a basin and depth in the sea. In addition, the similarities and differences in the

  7. Effects of Cactus Fiber on the Excretion of Dietary Fat in Healthy Subjects: A Double Blind, Randomized, Placebo-Controlled, Crossover Clinical Investigation

    Ralf Uebelhack, MD, PhD

    2014-12-01

    Conclusions: Cactus fiber has been shown to significantly promote fecal fat excretion in healthy adults. The results of our study support the hypothesis that cactus fiber helps in reducing body weight by binding to dietary fat and increasing its excretion, thus reducing dietary fat available for absorption. ClinicalTrials.gov identifier: NCT01590667.

  8. Effects of different ratios of straw to N-fertilizer on growth of Malus hupehensis seedling and its absorption, distribution and utilization of nitrogen

    CUI Tong-Li; JIANG Yuan-Mao; PENG Fu-Tian; WEI Shao-Chong

    2012-01-01

    Aims The study was to explore the effects of different ratios of straw to N-fertilizer on growth of Malus hupehensis seedlings and 15 N absorption, distribution and utilization in them.Methods Using 15N trace technique, we measured growth parameters (plant height, basal stem diameter and dry weight) and 15N parameters (absorption, N derived from fertilizer, distribution and utilization) of two-year-old M.hupehensis seedlings and C/N ratio in soil organic matter under different straw-nitrogen ...

  9. Sexual differences in the excretion of organic and inorganic mercury by methyl mercury-treated rats

    Adult male and female Long Evans rats received 1 mumole of methyl (203Hg) mercuric chloride per kilogram sc. Whole-body retention of mercury and excretion of organic and inorganic mercury in urine and feces were monitored for 98 days after dosing. Females cleared mercury from the body more rapidly than did males. The major route of mercury excretion was feces. By 98 days after dosing, cumulative mercury excretion in feces accounted for about 51% of the dose in males and about 54% of the dose in females. For both sexes, about 33% of the dose was excreted in feces as inorganic mercury. Cumulative excretion of organic mercury in feces accounted for about 18 and 21% of the dose in males and females, respectively. Urinary excretion of mercury was quantitatively a smaller route for mercury clearance but important sexual differences in loss by this route were found. Over the 98-day experimental period, males excreted in urine about 3.2% of the dose and females excreted 7.5%. Cumulative organic Hg excretion in urine accounted for 1.8% of the dose in males and 5.3% of the dose in females. These sexual differences in urinary and fecal excretion of organic and inorganic mercury following methyl mercury treatment were consistent with previous reports of sexual differences in mercury distribution and retention in methyl mercury-treated rats, particularly sexual differences in organic mercury uptake and retention in the kidney. Relationships between body burdens of organic or inorganic Hg and output of these forms of Hg in urine and feces were also found to be influenced by the interval after MeHg treatment and by sex. Relationship between concentration of Hg in liver and feces and in kidney and urine differed for organic and inorganic Hg and depended upon sexual status and interval after MeHg treatment

  10. Quality assurance in excretion analysis

    According to the German 'Guideline for Requirements for Measuring Laboratories', the accuracy of the measurement data (bias and precision), shall be certified by internal laboratory controls and by the participation in intercomparisons. Test criteria to assess the accuracy of the results are present according to the Guideline. The preconditions for sufficient accuracy and the importance of the internal laboratory controls and of the intercomparisons are discussed. Evaluation of the intercomparisons initiated from 1981 to 98 by the Working Group Incorporation Monitoring (AKI) of the German-Swiss Radiation Protection Association shows that the majority of the laboratories performing excretion analyses fulfil the test criteria of the Guideline. However, for the different reasons presented here, the tests are less representative for the results obtained under routine conditions. In this context, greater significance is attached to own internal controls in laboratories. If the control samples are introduced randomly and anonymously into the routine analysis, than their results can create the basis for a quantitative assessment of the quality level of all laboratory results. (orig.)

  11. Hyperuricemia in acute gastroenteritis is caused by decreased urate excretion via ABCG2.

    Matsuo, Hirotaka; Tsunoda, Tomoyuki; Ooyama, Keiko; Sakiyama, Masayuki; Sogo, Tsuyoshi; Takada, Tappei; Nakashima, Akio; Nakayama, Akiyoshi; Kawaguchi, Makoto; Higashino, Toshihide; Wakai, Kenji; Ooyama, Hiroshi; Hokari, Ryota; Suzuki, Hiroshi; Ichida, Kimiyoshi; Inui, Ayano; Fujimori, Shin; Shinomiya, Nariyoshi

    2016-01-01

    To clarify the physiological and pathophysiological roles of intestinal urate excretion via ABCG2 in humans, we genotyped ABCG2 dysfunctional common variants, Q126X (rs72552713) and Q141K (rs2231142), in end-stage renal disease (hemodialysis) and acute gastroenteritis patients, respectively. ABCG2 dysfunction markedly increased serum uric acid (SUA) levels in 106 hemodialysis patients (P = 1.1 × 10(-4)), which demonstrated the physiological role of ABCG2 for intestinal urate excretion because their urate excretion almost depends on intestinal excretion via ABCG2. Also, ABCG2 dysfunction significantly elevated SUA in 67 acute gastroenteritis patients (P = 6.3 × 10(-3)) regardless of the degree of dehydration, which demonstrated the pathophysiological role of ABCG2 in acute gastroenteritis. These findings for the first time show ABCG2-mediated intestinal urate excretion in humans, and indicates the physiological and pathophysiological importance of intestinal epithelium as an excretion pathway besides an absorption pathway. Furthermore, increased SUA could be a useful marker not only for dehydration but also epithelial impairment of intestine. PMID:27571712

  12. Model for kidney-bladder excretion

    In order to calculate the effective dose, an explicit tissue weighting factor of 0.05 is given for the bladder. Consequently a model for kidney-bladder excretion is needed to calculate the additional equivalent dose to bladder wall from activity in urine. The mathematical expressions of the model were proposed in ICRP Pub. 53. However, the expressions can only be applied to the materials excreted directly through urine from body fluids. If the intakes were transferred among the tissues or organs of body successively and excreted in urine, the available expressions calculating disintegration of the intakes in urinary path and bladder contents were derived in this paper

  13. Urinary excretion of dietary Maillard reaction products in healthy adult female cats.

    van Rooijen, C; Bosch, G; Butré, C I; van der Poel, A F B; Wierenga, P A; Alexander, L; Hendriks, W H

    2016-01-01

    During processing of foods, the Maillard reaction occurs, resulting in the formation of advanced Maillard reaction products (MRP). Varying amounts of MRP have been found in commercially processed pet foods. Dietary MRP can be absorbed and contribute to the endogenous pool of MRP and possibly the etiology of age-related diseases. The aim of the present study was to determine urinary excretion of dietary MRP in cats fed commercial moist and dry foods. A pilot study with 10 cats, conducted to determine the adaptation time required for stable urinary excretion of MRP when changing to a diet with contrasting MRP content, showed an adaptation time of 1 d for all components. In the main study, 6 commercially processed dry and 6 moist diets were fed to 12 adult female cats in 2 parallel randomized, 36-d Latin square designs. The 24-h urine was collected quantitatively using modified litter boxes, and fructoselysine (FL), carboxymethyllysine (CML), and lysinoalanine (LAL) were analyzed using ultra high performance liquid chromatography (UHPLC) - mass spectrometer. Daily urinary excretion of FL and CML showed a positive relationship with daily intake in the dry ( = 0.03 and MRP were absorbed from the gastrointestinal tract of cats and excreted in the urine. The adaptation time with change in diet indicates a likely effective excretion of MRP. Minimum apparent absorption of FL, CML, and LAL was found to range between 8% and 23%, 25% and 73%, and 6% and 19%, respectively. The observed decrease in urinary recovery suggests a limiting factor in digestion, absorption, metabolism, or urinary excretion. This study shows that dietary MRP in commercial diets are absorbed and excreted via the kidneys in cats. PMID:26812325

  14. Concentration distribution of Nd{sup 3+} In Nd:Gd{sub 3}Ga{sub 5}O{sub 12} crystals studied by optical absorption method

    Sun, Dunlu; Zhang, Qingli; Wang, Zhaobing; Su, Jing; Gu, Changjiang; Wang, Aihua; Yin, Shaotang [Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, HeFei 230031 (China)

    2005-07-01

    Nd:Gd{sub 3}Ga{sub 5}O{sub 12} crystals with different concentrations of Nd{sup 3+} were grown by Czochralski method, their absorption spectra were measured at room temperature. By using the optical absorption method, the effective distribution coefficient k{sub eff} for Nd{sup 3+} in GGG was fitted to be 0.40{+-}0.01, which is higher than that of Nd{sup 3+} in YAG. The 808nm absorption cross-section was calculated to be 4.0{+-}0.2 x 10{sup -20} cm{sup -2}. The lengthways and radial concentration distribution of Nd{sup 3+} in the crystals were also analyzed and discussed. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  15. Calculation of the renal clearance by dynamic measurement of the excreted activity

    Aim: In this paper we present a new method to measure the renal slope-clearance of Tc-99m-MAG-3 in a single-shot model (Excretion-clearance). Method: A renal scintigraphy with Tc-99m-MAG-3 was performed in 22 patients. The excreted activity of the tracer in the kidneys and the bladder was dynamically measured using a double-head gamma-camera. Additionally, the total absorption over the kidneys and the bladder was determined. The Excretion-clearance was calculated in a differential and an integral variant. Simultaneously the 2-compartment-clearance (Sapirstein-clearance), the Oberhausen-clearance and the Bubeck-clearance were calculated. Results: The Sapirstein-clearance is considered as the 'goldstandard' in a single-shot modell. The correlation of the Bubeck-clearance and the Oberhausen-clearance ranged from r=0.96 to r=0.97, the Excretion-clearance (differential-method) correlated with r=0.90. The absolute difference of the clearance-values was lowest comparing the Bubeck-clearance with the Sapirstein-clearance with an average difference of 11%, whereas the Excretion-clearance revealed at least an average difference of 21% and the Oberhausen-clearance of 24%. Discussion: The Excretion-clearance requires a more complicated protocoll measuring the clearance in comparison to the Bubeck-clearance. The results of the excretion-clearance differ more from the Sapirstein-clearance with regard to the examined patient population than the Bubeck-clearance. Regarding the theoretical basis of the methods, we expect advantages of the Excretion-clearance compared with the Bubeck-clearance in patients with compartmental disproportion or with a low clearance. We are going to prove this in combination with the above mentioned methodical improvements in a further study. (orig.)

  16. Excretion of drugs in human breast milk

    Welch, R.M.; Findlay, J.W.

    1981-01-01

    The present report briefly discusses some of the morphological, physiological, and compositional aspects of animal and human breast milk and how these characteristics might be important for the accumulation of drugs and foreign compounds. In addition, a study is described confirming the presence of caffeine, codeine, morphine, phenacetin, acetaminophen, and salicylic acid in the breast milk of a lactating mother following oral administration of a combination analgesic containing aspirin, phenacetin, caffeine, and codeine. Although the study is limited to one subject, it has provided critically needed data on the rates of appearance in, and elimination of these drugs from, breast milk. A similar amount of information is presented on phenacetin, also a component of the analgesic mixture, which has not been previously reported to enter human milk. The distribution of these drugs between the slightly more acidic breast milk and the relatively neutral plasma is consistent with their weakly basic, acidic, or relatively neutral properties. In general, the study shows that codeine and morphine milk concentrations are higher than, salicylic acid milk levels are much lower than, and phenacetin, caffeine, and acetaminophen milk concentrations are relatively similar to their respective plasma levels. It is projected, from estimated steady-state milk concentrations of the drugs and their metabolites studied, that very low percentages of the therapeutic dosages (less than 0.7%) would be excreted in mother's milk, too low an amount to be clinically significant to the infant.

  17. Diagnostic Value of the Cobalt (58Co) Excretion Test in Iron Deficiency Anemia

    The diagnosis of iron deficiency rests upon the correct evaluation of body iron stores. Morphological interpretation of blood film and the red cell indices are not reliable and often absent in mild iron deficiency. Serum iron levels and iron-binding capacity are more sensitive indices of iron deficiency, but they are often normal in iron depletion and mild iron deficiency anemia. They are also subject ro many variables which may introduce substantial errors and influenced by many pathologic and physiologic states. Examination of the bone marrow aspirate for stainable iron has been regarded as one of the most sensitive and reliable diagnostic method for detecting iron deficiency, but this also has limitations. Thus, there is still need for a more practical, but sensitive and reliable substitute as a screening test of iron deficiency. Pollack et al. (1965) observed that the intestinal absorption of cobalt was raised in iron, deficient rats and Valberg et al. (1969) found that cobalt absorption was elevated in patients with iron deficiency. A direct correlation was demonstrated between the amounts of radioiron and radiocobalt absorbed. Unlike iron, excess cobalt was excreted by the kidney, the percentage of radioactivity in the urine being directly related to the percentage absorbed from the gastro-intestinal tract. Recently a test based on the urinary excretion of an oral dose of 57Co has been proposed as a method for detecting iron deficiency. To assess the diagnostic value of urinary cobalt excretion test cobaltous chloride labelled with 1 μCi of 58Co was given by mouth and the percentage of the test dose excreted in the urine was measured by a gamma counter. The mean 24 hour urinary cobalt excretion in control subjects with normal iron stores was 6.1%(1.9-15.2%). Cobalt excretion was markedly increased in patients with iron deficiency and excreted more than 29% of the dose. In contrast, patients with anemia due to causes other than iron deficiency excreted less

  18. Radioisotope studies for quantitative measurement of manganese absorption

    Purpose of the present study was to quantitatively determine the manganese absorption in growing rats by means of radioisotopes. First of all the following factors had to be investigated, which are significant for this determination: Measurability of stable and radioactive Mn in rat tissues; labelling of stable Mn and distribution of stable and radioactive Mn in the organism; verification of the isotope dilution method and of the comparative balance method with regard to its applicability for the determination of the true Mn absorption. We useed male and female Sprague-Dawley rats. The most important results are summarized in the following: in some separate tissues measurement of stable Mn was accompanied by difficulties. The measurement of radioactive Mn however, could be performed without any problems. 10 d after i.m. injection of 54Mn only 17% of the administered Mn was still detectable in the organism. However, there was no uniform tissue labelling found. Therefore it is possible to an only restricted extent to draw quantitative conclusions on the content of stable Mn. A high percentage of stable and radioactive Mn was found above all in the liver. The isotope dilution method permits by feces analysis to differentiate between unabsorbed Mn coming from the food and endogenic Mn coming from the organism itself. The effective Mn absorption was also determined by means of the comparative balance method. By means of the isotope dilution method we determined the quantitative Mn-absorption with staged Mn administration and the contribution of absorption and excretion to the homeostatic regulation mechanisms of Mn. We found that absorption and excretion help the organism to keep an almost constant Mn concentration even with a differing Mn supply. (orig./MG)

  19. Iodine excretion in school children in Copenhagen

    Rasmussen, Lone B; Kirkegaard-Klitbo, Ditte Marie; Laurberg, Peter;

    2016-01-01

    INTRODUCTION: Studies of dietary habits show a high iodine intake in children in Denmark. Iodine excretion in children has not previously been assessed. Iodine excretion in adults is below the recommended threshold, and it is therefore being discussed to increase the fortification level. The main...... objective of this study was to assess iodine excretion in children living in Copenhagen to establish whether a moderate increase in iodine fortification would lead to excess iodine intake in this group. METHODS: Children in first and fifth grade were recruited through schools in Copenhagen. In total, 244...... according to grade. The UIC was higher in children than in adults from the same area. CONCLUSIONS: The iodine excretion among schoolchildren in Copenhagen, an area with a relatively high iodine content in tap water, was within the recommended range as assessed by the UIC. An increased iodine fortification...

  20. Maggot Excretions Inhibit Biofilm Formation on Biomaterials

    Cazander, G.; Veerdonk, van de, RJM Rene; Vandenbroucke-Grauls, C. M. J. E.; Schreurs, M.W.J.; Jukema, G.N.

    2010-01-01

    Background Biofilm-associated infections in trauma surgery are difficult to treat with conventional therapies. Therefore, it is important to develop new treatment modalities. Maggots in captured bags, which are permeable for larval excretions/secretions, aid in healing severe, infected wounds, suspect for biofilm formation. Therefore we presumed maggot excretions/secretions would reduce biofilm formation. Questions/purposes We studied biofilm formation of Staphylococcus aureus, Staphylococcus...

  1. 朱砂灌胃给药后汞在孕大鼠脏器内的分布和排泄途径研究%Study on Distribution in Organs and Excretion Pathway of Mercury in Pregnant Rats after Administration of Cinnabar

    汤家铭; 米金霞; 吴文斌; 谷颖敏; 李咏梅; 夏晶; 张甦; 曹帅; 季申

    2011-01-01

    Objective: To study the distribution and excretion pathway of mercury in pregnant rats after administration of cinnabar. Methods; Compared with the reproductive toxicity test, the female SD rats after mating were randomly divided into high (1 000 mg/kg) , medium (300 mg/kg) , and low-dose (100 mg/kg) cinnabar groups, and negative control group (0.5% CMC-Na) , with ten rats in each group. The rats in different dose cinnabar groups were administered intragastrically with cinnabar from the sixth day to the fifteenth day after pregnancy, and all the rats were sacrificed on the twentieth day of pregnancy. The main organs (including heart, liver, spleen, lung, kidney, brain and uterus) , blood, placentae, fetuses and urine of the pregnant rats were obtained to detect the mercury concentration by inductively coupled plasma mass spectrometry ( ICP-MS) ; the feces were taken at different time points to determine the mercury concentration by inductively coupled plasma optical emission spectrometer (ICP-OES) ; the distribution in different organs and the excretion pathway of mercury were analyzed. Results: The mercury concentrations of the heart, liver, kidney and uterus of the rats in different dose cinnabar groups were higher than those of the rats in negative control group, and the concentration increased with the enhanced dose; there was no statistical difference on the mercury concentrations of the brain, placentae and fetuses between different dose cinnabar groups and negative control group. There were large amount of mercury in the feces on the second day after administration, and the mercury excretion accounted for 38. 2% ~ 50.4% of HgS intake; while the mercury excretion accounted for72.2% -86.6% on the tenth day after administration; The a-mount of HgS discharged in the feces decreased rapidly on the fourth day after drug discontinuation. Only extreme trace of mercury excreted from urine with dose-dependent pattern, and the mercury excretion maintained the high

  2. Enabling the Distributed Generation Market of High Temperature Fuel Cell and Absorption Chiller Systems to Support Critical and Commercial Loads

    DiMola, Ashley M.

    Buildings account for over 18% of the world's anthropogenic Greenhouse Gas (GHG) emissions. As a result, a technology that can offset GHG emissions associated with buildings has the potential to save over 9 Giga-tons of GHG emissions per year. High temperature fuel cell and absorption chiller (HTFC/AC) technology offers a relatively low-carbon option for meeting cooling and electric loads for buildings while producing almost no criteria pollutants. GHG emissions in the state of California would decrease by 7.48 million metric tons per year if every commercial building in the State used HTFC/AC technology to meet its power and cooling requirements. In order to realize the benefits of HTFC/AC technology on a wide scale, the distributed generation market needs to be exposed to the technology and informed of its economic viability and real-world potential. This work characterizes the economics associated with HTFC/AC technology using select scenarios that are representative of realistic applications. The financial impacts of various input factors are evaluated and the HTFC/AC simulations are compared to the economics of traditional building utilities. It is shown that, in addition to the emissions reductions derived from the systems, HTFC/AC technology is financially preferable in all of the scenarios evaluated. This work also presents the design of a showcase environment, centered on a beta-test application, that presents (1) system operating data gathered using a custom data acquisition module, and (2) HTFC/AC technology in a clear and approachable manner in order to serve the target audience of market stakeholders.

  3. A novel description of FDG excretion in the renal system: application to metformin-treated models

    Garbarino, S.; Caviglia, G.; Sambuceti, G.; Benvenuto, F.; Piana, M.

    2014-05-01

    This paper introduces a novel compartmental model describing the excretion of 18F-fluoro-deoxyglucose (FDG) in the renal system and a numerical method based on the maximum likelihood for its reduction. This approach accounts for variations in FDG concentration due to water re-absorption in renal tubules and the increase of the bladder’s volume during the FDG excretion process. From the computational viewpoint, the reconstruction of the tracer kinetic parameters is obtained by solving the maximum likelihood problem iteratively, using a non-stationary, steepest descent approach that explicitly accounts for the Poisson nature of nuclear medicine data. The reliability of the method is validated against two sets of synthetic data realized according to realistic conditions. Finally we applied this model to describe FDG excretion in the case of animal models treated with metformin. In particular we show that our approach allows the quantitative estimation of the reduction of FDG de-phosphorylation induced by metformin.

  4. Tissue distribution and excretion of baicalein and its main metabolite in rats by LC-MS/MS%LC-MS/MS法研究黄芩素及其主要代谢物在大鼠体内的组织分布与排泄

    柳文媛; 徐维露; 李萍; 冯锋; 丁黎

    2009-01-01

    目的:研究黄芩素及其主要代谢物黄芩苷在大鼠体内组织分布及排泄.方法:液相色谱分离采用C_(18)柱(150mm ×6.0 mm,5 μm),甲醇-10 mmol/L醋酸铵溶液(含0.5%甲酸)(70:30)为流动相;质谱检测采用ESI离子源,正离子SRM方式检测.生物样品处理采用加入磷酸盐缓冲液,以甲醇-乙腈(1:1)提取,上清液以氮气流吹干,流动相复溶进样分析.结果:大鼠灌服黄芩素,原形药物及其主要代谢物在大鼠体内分布在20~40 min及10 h呈现双峰现象,与血药浓度曲线规律一致.给药20 min后肾组织中代谢物浓度显著高于原形,胃、肝及肠中原形药物浓度高于代谢物,肺中两者接近.排泄研究显示,大鼠胆汁与尿液中代谢物浓度远高于原形药物,而在粪便中以原形药物为主.结论:黄芩素在大鼠体内吸收迅速,20~40 min迅速分布至各主要脏器,并发生生物转化.%Aim: To study the distribution and excretion of baicalein and baicalin in rats. Methods: An LC/MS method was applied. Chromatographic separation was performed on a C_(18) column( 150 mm ×6.0 mm, 5 μm) with methanol-10 mmol/L ammonium acetate (containing 0. 5% formic acid) as the mobile phase. A trip-quadrupole tandem mass spectrometer was set in positive selected reaction monitoring mode. The sample was extracted with methanol-acetonitrile( 1:1) after the addition of phosphoric buffer solution and luteolin, which acted as the internal standard. The supernatant was evaporated to dryness, and the residual was reconstituted with mobile phase and analyzed. Results: The distribution profiles of the parent drug and its main metabolite showed two peaks between 20-40 min and 8-10 h after oral administration of baicalein, which fit the plasma concentration-time profile of baicalein in rats. At 20 min after the dosing, the concentration levels of baicalein were significantly higher than those of baicalin in stomach, liver and intestines, the converse result occurred in

  5. Urinary porphyrin excretion in hepatitis C infection.

    Vogeser, M; Jacob, K; Zachoval, R

    1999-08-01

    A high prevalence of hepatitis C virus infection in porphyria cutanea tarda in some populations suggests a close link between viral hepatitis and alteration of porphyrin metabolism. Moreover, there is evidence of a role of porphyrinopathies in hepatocarcinogenesis. The aim of our study was to obtain data on the prevalence and patterns of heme metabolism alterations in patients with chronic hepatitis C virus infection. Urinary porphyrin excretion was prospectively studied in 100 consecutive outpatients with chronic hepatitis C infection without signs of photosensitivity, using an ion-pair high-performance liquid chromatography method. Increased total porphyrin excretion was found in 41 patients, with predominant excretion of coproporphyrins (whole study group: mean 146 microg/g creatinine, interquartile range 76-186; normal coproporphyrin, heptacarboxyporphyrin III increased) but the total porphyrin excretion was only slightly elevated in this case. In the whole group, total urinary porphyrin excretion correlated well with serum bilirubin and was inversely correlated with albumin and thrombin time. In conclusion, secondary coproporphyrinuria occurs frequently in heptatitis C infection, whereas in Germany, preclinical porphyria cutanea tarda seems to be rare in these patients. PMID:10536928

  6. Enhancement of radiopharmaceutical excretion by chemical interventions

    The goal was to find methods of decreasing the radiation dose after radionuclide studies, by giving a compound that will increase the rate of excretion of the radionuclide. Sprague - 1 Dawley rats were given Tc-99m pertechnetate, Ga-67 citrate or Tl-201 chloride intravenously followed at intervals of 1 to 24 hours by one of the following compounds: desferroxamine (DFO), 2,3-dimercapto-1-propanol (BAL), triethylene tetraamine hexaacetic acid (TETHA), stannous tartarate, bleomycin (BLEO), 2,3-dimercaptosuccinic acid (DMSA), diethylene-triaminepentaacetic acid (DTPA), DTPA+SnCl.2H2O, dihydroxybenzoic acid (DHB), and ferric-cyanoferrate (IT)(Prussian blue, PB). All the agents except PB are chelators. Some of these agents enhance excretion through the urinary tract (DFO), while most are excreted through the bile. PB was shown to increase Cs excrection through the G.I. tract

  7. Enhancement of radiopharmaceutical excretion by chemical interventions

    Oster, Z.H.; Som, P.; Brill, A.B.; Sacker, D.F.; Atkins, H.L.

    1982-01-01

    The goal was to find methods of decreasing the radiation dose after radionuclide studies, by giving a compound that will increase the rate of excretion of the radionuclide. Sprague - 1 Dawley rats were given Tc-99m pertechnetate, Ga-67 citrate or Tl-201 chloride intravenously followed at intervals of 1 to 24 hours by one of the following compounds: desferroxamine (DFO), 2,3-dimercapto-1-propanol (BAL), triethylene tetraamine hexaacetic acid (TETHA), stannous tartarate, bleomycin (BLEO), 2,3-dimercaptosuccinic acid (DMSA), diethylene-triaminepentaacetic acid (DTPA), DTPA+SnCl.2H/sub 2/O, dihydroxybenzoic acid (DHB), and ferric-cyanoferrate (IT)(Prussian blue, PB). All the agents except PB are chelators. Some of these agents enhance excretion through the urinary tract (DFO), while most are excreted through the bile. PB was shown to increase Cs excrection through the G.I. tract. (ACR)

  8. Tissular localization and excretion of intravenously administered silica nanoparticles of different sizes

    Xie Guangping; Sun Jiao, E-mail: jiaosun59@yahoo.com [Shanghai Jiaotong University School of Medicine, Shanghai Biomaterials Research and Testing Center, Shanghai Ninth People' s Hospital (China); Zhong Gaoren [Fudan University, School of Pharmacy (China)

    2012-01-15

    The nanotoxicology as a new subdiscipline of nanotechnology needs to be studied in vivo. To do so, it is essential to understand certain pharmacological information of the nanoparticles in vivo. Silica nanoparticles (SiNPs) have been developed for a number of biomedical uses; however, research on their tissular localization and excretion has been limited. In this study, we analyzed the localization of intravenously administered SiNPs with sizes of 20 and 80 nm in liver and spleen and quantitatively investigated the excretion of SiNPs through urine and feces. The results of the tissular localization study showed that the SiNPs were located in liver evenly; however, they were mainly accumulated in the white pulp of spleen. The quantitative excretory assay found the renal excretion being the main excretion pathway of SiNPs and indicated that the accumulated excretory rate of 80 nm SiNPs through urine was higher than that of 20 nm SiNPs because of the higher hemoconcentration. Further analysis of radioactive substances in the excreta showed the convincing confirmatory evidence that the SiNPs of both the sizes of 20 and 80 nm could be excreted through urine. These results provide important information on in vivo distribution and excretion of SiNPs.

  9. A screening model of drug absorption, distribution, metabolism and excretion in vitro%药物体外吸收、分布、代谢和排泄筛选模型

    王琳; 陈涵

    2008-01-01

    药物在吸收、分布、代谢和消除过程中具有良好的药代动力学性质和较低的毒副作用是候选药物通过临床试验的关键所在.这就需要合理的体外模型来对药物的体内行为进行预测.总结已有的、用于研究药物的吸收、分布、代谢、消除和药物毒性,基于细胞水平的体外模型.目前药物肠吸收的模型主要有动物体内实验和使用人造细胞膜、细胞系及肠组织的体外实验;约物分布模型包括药物与血清蛋白结合模型、药物向各组织分布的模型及透血脑屏障模型:药物代谢包括代谢稳定性、药物相互作用及约物毒性几方面.

  10. Intestinal excretion of metals by rats

    The excretion of 65Zn, sup(115m)Cd, 203Hg, 207Bi, 210Pb, 60Co, 64Cu, 85Sr and 86Rb in the perfused sections of the intestinal tract in vivo was investigated by the pendular perfusion method. After intravenous administration the excretion of metals was investigated in the jejunum, in the colon and in some experiments also in the ileum. The fluid net movement in the jejunum and colon was measured in dependency on the energy spectrum of the applied metal isotope by means of 14C or 3H-polyethylene glycol 2000. (orig./MG)

  11. Biodistribution and excretion of 125I ioversol in conscious dogs

    Radiolabeled ioversol was injected intravenously into two male and two female beagle dogs (6.7 to 10.4 kg) at two dose levels each (0.2 and 1.0 g I/kg). Blood levels of radioactivity were monitored at 2, 5, 10, 20, 40, 60, 90, and 120 minutes and at one and two days. Urine and feces were collected in metabolism cages for two days, at the end of which the dogs were killed and organs or tissues (kidneys, liver, spleen, lungs, thyroid glands, heart, gonads, and muscle) were sampled. Radioactivity in tissues and excreta was assayed. Biexponential disappearance of radioactivity from blood was observed in three of four dogs at each dose level. Distribution half-lives averaged 2.5 to 3.5 minutes. Elimination half-lives averaged 51 to 54 minutes. Volumes of distribution averaged 25% to 27% of body weight. No organ retention was evident at 48 hours. Recovery of ioversol in urine and feces averaged 86% to 88% of the administered dose, of which all but a few percent was recovered in urine. On chromatographic assay, ioversol accounted for an average of 103% to 109% of radioiodine, suggesting, within the experimental limits of the assay, that ioversol is excreted unchanged. No dose-related differences were evident in any of these measures. The pharmacokinetics and biodistribution of ioversol are consistent with those of other extracellularly distributed iodinated contrast agents that are excreted by the kidney

  12. Clinical study of urinary excretion of Ga-67

    Ga-67 urinary excretion was examined in 59 patients. The 72-hour urinary excretion rate ranged from 4.3 to 67.8% of the injected dose. Within the first 24 hours, 60.9% of the 72-hour urinary excretion was excreted. There was no significant difference in the Ga-67 urinary excretion rate between males and females, nor between the Ga-67 positive and negative cases. A significant negative correlation was found between the 72-hour Ga-67 urinary excretion rate and the unsaturated iron binding capacity. Notably, four patients with hyperferremia, which was considered secondary to leukemia and/or chemotherapy or liver cirrhosis, excreted more than 46.8% of Ga-67 within 72 hours. A significant negative correlation was also found between the 72-hour Ga-67 urinary excretion rate and age. Urinary excretion of Ga-67 may be related to the glomerular filtration rate, which decreases with age

  13. Regional distribution and variation of gamma-globulin absorption from the small intestine of the neonatal calf

    125I-labeled immunoglobulin (Ig)G1 in colostral whey was used to determine the region of maximum absorption of Ig from the small intestine of the neonatal calf and the variation in Ig absorption among calves at the intestinal level. In experiment 1, 5 segments (approx 5%, 35%, 60%, 80%, and 95% of the duodenocecal length) were formed in the small intestine of 9 colostrum-deprived calves shortly after birth. These segments were injected with colostral whey containing 125I-IgG1 4 hours after birth, and uptake, transfer, and absorption (defined as uptake plus transfer) were determined for each segment 2 hours later. Raw data were adjusted for the milligrams of IgG1 injected per gram of intestinal tissue to obtain the least squares mean (LSM) value. The LSM values for absorption of IgG1 from distal segments 3, 4, and 5 were significantly greater (P less than 0.05) than those values for proximal segments 1 and 2. The region of the maximum IgG1 absorption was the lower small intestine, 60% to 80% of the duodenocecal length. There was also an indication of independence between uptake and transfer in each of the segments. Significant differences (P less than 0.05) were present among calves in the LSM values for uptake and absorption, but not for transfer. In experiment 2, thoracic ducts of 8 newborn calves were cannulated 4 to 5 hours after birth. At 6 hours after birth, colostral whey with 125I-IgG1 was injected into an intestinal segment (approx 60% to 80% of the duodenocecal length)

  14. Intestinal radiocalcium transport versus urinary excretion in long term 1.25(OH)2D3 tratment

    The effects of a long-term (4-24 months) treatment with physiological doses of 1,25(OH)2D3 (without calcium supplementation) on various parameters related to calcium metabolism and renal function were investigated in postmenopausal osteoporotic patients. On 1,25(OH)2D3 treatment, the intestinal calcium absorption increased remarkably, as did urinary calcium excretion; on the other hand, hydroxyproline excretion remained unchanged, whereas the cAMP/creatinine ratio in urine decreased. No change was observed concerning blood urea nitrogen and creatinine clearance, and no renal stones developed. The conclusion is that the increase in urinary calcium excretion ocurring on long-term treatment with 1,25(OH)2D3 reflects the increase in calcium absorption without a significant resorptive component and, under the conditions of the present study, has no effect on renal function

  15. Power Functions Relating Excretion to Body Burden

    Sanders, S M J

    2003-01-01

    Formulae necessary to relate the quantity of radionuclides excreted to that assimilated in exposures that are acute and those that are multiple or continuous are derived from power function relationships. Particular attention is given to providing equations having variables for which the bioassayer can easily derive numerical values. This paper presents this data.

  16. Comparison and validation of two analytical methods for measurement of urinary sucrose and fructose excretion

    Song, Xiaoling; Navarro, Sandi L.; Diep, Pho; Thomas, Wendy K.; Razmpoosh, Elena C.; Schwarz, Yvonne; Wang, Ching-Yun; Kratz, Mario; Neuhouser, Marian L; Lampe, Johanna W.

    2013-01-01

    Urinary sugars excretion has been proposed as a potential biomarker for intake of sugars. In this study we compared two analytical methods [gas chromatography (GC) and enzymatic reactions – UV absorption] for quantifying urinary fructose and sucrose using 24-hour urine samples from a randomized cross-over controlled feeding study. All samples were successfully quantified by the GC method; however 21% and 1.9% of samples were below the detection limit of the enzymatic method for sucrose and fr...

  17. Combined assessment of intestinal disaccharidases in congenital asucrasia by differential urinary disaccharide excretion.

    Maxton, D G; Catt, S.D.; Menzies, I S

    1990-01-01

    Investigation of intestinal disaccharide hydrolysis and permeability by means of a non-invasive differential sugar absorption test was performed in a family containing two siblings with primary sucrase-isomaltase deficiency. The procedure, which depends on measurement of urinary excretion ratios after the oral administration of lactose, sucrose, palatinose, lactulose and L-rhamnose, is capable of simultaneous determination of intestinal lactase, sucrase, and isomaltase activity and lactulose:...

  18. Analysis of Correlation Between Urinal Excretion Ratio of Radioactive Iodine and Daily Urinal Excretion Volume

    Internal exposure to radionuclide results from depositing of radioactive substance within human body and is called intra-body exposure as well. Radioactive substance may find its way into human body via nose, mouth or skin and internal exposure to radionuclide is rarely ascribable to radioactive substance deposited through skin. Radioactive substances deposited in human tissues or organs do not stay there for good. Instead, they are transferred to other tissues, organs or excreted by sweat, excrements, urine and breath. However, natural excretion has its limits in terms of safeguarding human body actively against radioactive exposure. When radionuclide is deposited in human organs or tissues, diuretic or evacuant is used to induce excrements or urine to increase removal and discharging of radionuclide artificially, thereby reducing internal exposure. Therefore, we have attempted to propose an optimum approach to removing and excreting radioactive iodine by analyzing the correlation among the radioactive iodine intake ratio, daily urinal excretion ratio and volume

  19. Analysis of Correlation Between Urinal Excretion Ratio of Radioactive Iodine and Daily Urinal Excretion Volume

    Kim, Junghoon; Whang, Jooho [Kyunghee Univ., Yongin (Korea, Republic of); Kim, Teaman [The Korea Institute of Nuclear Safety, Taejon (Korea, Republic of)

    2006-07-01

    Internal exposure to radionuclide results from depositing of radioactive substance within human body and is called intra-body exposure as well. Radioactive substance may find its way into human body via nose, mouth or skin and internal exposure to radionuclide is rarely ascribable to radioactive substance deposited through skin. Radioactive substances deposited in human tissues or organs do not stay there for good. Instead, they are transferred to other tissues, organs or excreted by sweat, excrements, urine and breath. However, natural excretion has its limits in terms of safeguarding human body actively against radioactive exposure. When radionuclide is deposited in human organs or tissues, diuretic or evacuant is used to induce excrements or urine to increase removal and discharging of radionuclide artificially, thereby reducing internal exposure. Therefore, we have attempted to propose an optimum approach to removing and excreting radioactive iodine by analyzing the correlation among the radioactive iodine intake ratio, daily urinal excretion ratio and volume.

  20. Method for obtaining more precise measures of excreted organic carbon

    A new method for concentrating and measuring excreted organic carbon by lyophilization and scintillation counting is efficient, improves measurable radioactivity, and increases precision for estimates of organic carbon excreted by phytoplankton and macrophytes

  1. Modelling phosphorus intake, digestion, retention and excretion in growing and finishing pigs: model description.

    Symeou, V; Leinonen, I; Kyriazakis, I

    2014-10-01

    Low phosphorus (P) digestibility combined with intensive pig production can increase P diffuse pollution and environmental load. The aim of this paper was to develop a deterministic, dynamic model able to represent P digestion, retention and ultimately excretion in growing and finishing pigs of different genotypes, offered access to diets of different composition. The model represented the limited ability of pig endogenous phytase activity to dephosphorylate phytate as a linear function of dietary calcium (Ca). Phytate dephosphorylation in the stomach by exogenous microbial phytase enzymes was expressed by a first order kinetics relationship. The absorption of non-phytate P from the lumen of the small intestine into the blood stream was set at 0.8 and the dephosphorylated phytate from the large intestine was assumed to be indigestible. The net efficiency of using digested P was set at 0.94 and assumed to be independent of BW, and constant across genotype and sex. P requirements for both maintenance and growth were made simple functions of body protein mass, and hence functions of animal genotype. Undigested P was assumed to be excreted in the feaces in both soluble and insoluble forms. If digestible P exceeded the requirements for P then the excess digestible P was excreted through the urinary flow; thus the model represented both forms of P excretion (soluble and insoluble) into the environment. Using a UK industry standard diet, model behaviour was investigated for its predictions of P digestibility, retention and excretion under different levels of inclusion of microbial phytase and dietary Ca, and different non-phytate P : phytate ratios in the diet, thus covering a broad space of potential diet compositions. Model predictions were consistent with our understanding of P digestion, metabolism and excretion. Uncertainties associated with the underlying assumptions of the model were identified. Their consequences on model predictions, as well as the model

  2. LORRY DRIVERS WORK STRESS EVALUATED BY CATECHOLAMINES EXCRETED IN URINE

    VANDERBEEK, AJ; MEIJMAN, TF; FRINGSDRESEN, MHW; KUIPER, JI

    1995-01-01

    Objectives-To evaluate lorry drivers' work stress by measurement of adrenaline and noradrenaline excreted in the urine, and to find out which factors in their working situation are related to the excretion rates of these catecholamines. Methods-The urinary excretion of adrenaline and noradrenaline o

  3. Urinary iron excretion test in iron deficiency anemia.

    Kimura,Ikuro; Yamana,Masatoshi; NNishishita,Akira; Sugiyama,Motoharu; Miyata, Akira

    1980-01-01

    A urinary iron excretion test was carried out in 22 patients with iron deficiency anemia. The iron excretion index was significantly higher in patients with intractable iron deficiency anemia compared with normal subjects and anemic patients who were responsive to iron therapy. The findings suggest that iron excretion may be a factor that modulates the response of patients to iron therapy.

  4. Development and validation of an UPLC-MS/MS method for the quantification of ethoxzolamide in plasma and bioequivalent buffers: Applications to absorption, brain distribution, and pharmacokinetic studies

    Gao, Song; Zhao, Jing; Yin, Taijun; Ma, Yong; Xu, Beibei; Moore, Anthony N.; Dash, Pramod K.; Hu, Ming

    2015-01-01

    The purpose of this study is to develop and validate an UPLC-MS/MS method to quantify ethoxzolamide in plasma (EZ) and apply the method to absorption, brain distribution, as well as pharmacokinetic studies. A C18 column was used with 0.1% of formic acid in acetonitrile and 0.1% of formic acid in water as the mobile phases to resolve EZ. The mass analysis was performed in a triple quadrupole mass spectrometer using multiple reaction monitoring (MRM) with positive scan mode. The results show th...

  5. Comparative study of absorption and distribution of dexamethasone 3H after percutaneous or oral administration in mice and rats

    Percutaneous absorption of dexamethasone in alcoholic solution in mice and rats was low. Permeability constant measured on mice was included between 1.05 and 1.39.10-5cm/h. Under the site of application, a retention appeared in subcutaneous tissue and skeletal muscles which explained local pharmacological action. In other tissues (plasma, liver, kidney, adrenals and muscles), level of corticoid remained very low. On the contrary after oral administration, dexamethasone was present everywhere, concentration was the highest in liver and kidney

  6. The ℓ-distribution method for modeling non-gray absorption in uniform and non-uniform gaseous media

    André, Frédéric

    2016-08-01

    The ℓ-distribution modeling is proposed for radiative heat transfer in uniform and non-uniform non-gray gaseous media. The method is partly based on the application of results from the k-moment method. It combines this technique with several concepts from probability theory: the notion of rank transmutation maps allows extending the k-moment method to an infinite number of k-moments; copula models appear naturally to extend the method from uniform to non-uniform gas paths. The ℓ-distribution approach is shown to provide results: (1) more accurate - up to three orders of magnitude - than usual k-distribution approaches in uniform media, (2) as precise as correlated-k models in non-uniform situations. All these results are obtained at a computational cost lower than k-distribution models. Differences and similarities between k- and ℓ-distribution methods are discussed.

  7. Longitudinal study of the excretion patterns of thermophilic Campylobacter spp. in young pet dogs in Denmark

    Hald, Birthe; Pedersen, Karl; Wainø, Michael;

    2004-01-01

    Campylobacter-selective media CAT and modified CCDA agar at 37 and 42 C. This study comprised 366 fecal swab samples, of which 278 (76.2%) were found to be Campylobacter positive, with the following distribution of species: 75.0% Campylobacter upsaliensis, 19.4% Campylobacter jejuni, 2.1% Campylobacter lari, 0...... concurrent minor mutative changes) or independent strains. In contrast, the excreted C. jejuni isolates were much more diverse and, in most cases, only seen in one sample from each dog. A high degree of diversity among different dogs was seen. We conclude that young domestic pet dogs excreted Campylobacter...

  8. Excretion rates of uranium in urine

    Summarising the results obtained at RB Hanau, the following statements are made: For determination of the contribution of uranium excreted in urine emanating from intake through the diet, a carefully planned measuring programme should be performed with individuals whose examination delivered reliable evidence that they have not been exposed before. The measuring methods of the participating laboratories are to be monitored for comparability and reproducibility of results, for corrections to be made if necessary. In order to eliminate or flatten individual fluctuations in excretion, urine samples collected over two or more subsequent days should be used for monitoring. The highest detection limit to be required for the programme should be at least 1 mBq for one daily sample. (orig./CB)

  9. Urinary porphyrin excretion in hepatitis C infection

    Vogeser, Michael; Jacob, Karl; Zachoval, Reinhart

    1999-01-01

    A high prevalence of hepatitis C virus infection in porphyria cutanea tarda in some populations suggests a close link between viral hepatitis and alteration of porphyrin metabolism. Moreover, there is evidence of a role of porphyrinopathies in hepatocarcinogenesis. The aim of our study was to obtain data on the prevalence and patterns of heme metabolism alterations in patients with chronic hepatitis C virus infection. Urinary porphyrin excretion was prospectively studied in 100 consecutive ou...

  10. Urine alkalization facilitates uric acid excretion

    Seyama Issei

    2010-10-01

    Full Text Available Abstract Background Increase in the incidence of hyperuricemia associated with gout as well as hypertension, renal diseases and cardiovascular diseases has been a public health concern. We examined the possibility of facilitated excretion of uric acid by change in urine pH by managing food materials. Methods Within the framework of the Japanese government's health promotion program, we made recipes which consist of protein-rich and less vegetable-fruit food materials for H+-load (acid diet and others composed of less protein but vegetable-fruit rich food materials (alkali diet. Healthy female students were enrolled in this consecutive 5-day study for each test. From whole-day collected urine, total volume, pH, organic acid, creatinine, uric acid and all cations (Na+,K+,Ca2+,Mg2+,NH4+ and anions (Cl-,SO42-,PO4- necessary for the estimation of acid-base balance were measured. Results Urine pH reached a steady state 3 days after switching from ordinary daily diets to specified regimens. The amount of acid generated ([SO42-] +organic acid-gut alkai were linearly related with those of the excretion of acid (titratable acidity+ [NH4+] - [HCO3-], indicating that H+ in urine is generated by the metabolic degradation of food materials. Uric acid and excreted urine pH retained a linear relationship, where uric acid excretion increased from 302 mg/day at pH 5.9 to 413 mg/day at pH 6.5, despite the fact that the alkali diet contained a smaller purine load than the acid diet. Conclusion We conclude that alkalization of urine by eating nutritionally well-designed food is effective for removing uric acid from the body.

  11. Endogenous phosphorus excretion by sheep fed hydrolyzed sugarcane bagasse, lucerne hay and citrus pulp

    The objective of this study was to determine endogenous phosphorus excretion in sheep fed with different diets. Sixteen male growing sheep, received a basic diet with: 42% hydrolyzed sugarcane bagasse (HSB), 45% lucerne hay (LH) plus 14% hydrolyzed sugarcane bagasse, and 30% citrus pulp (CTP) plus 40% hydrolyzed sugarcane bagasse. A dose of 7.7 MBq 32P was injected into the left jugular vein of each animal. The P endogenous fecal losses were: 1.69, 2.50, 2.33 and 1.45 g/animal for treatments HSB, LH, and CTP respectively (P>0.05). The type of diet influenced slight endogenous P excretion but altered excretion of P in urine. Endogenous P excreted in feces (PF) comes mainly from saliva and represents an important loss of P. The estimation of net requirements of phosphorus (P) for ruminants includes endogenous losses, which is also essential for calculating true absorption of this mineral. Physical structure of the feed may influence endogenous losses, altering the metabolism of P and also the demand of this mineral, therefore being important to know how different feeds affect endogenous P losses. (author)

  12. Bioaccessibility and excretion of arsenic in Niu Huang Jie Du Pian pills

    Traditional Chinese medicines (TCMs) often contain significant levels of potentially toxic elements, including arsenic. Niu Huang Jie Du Pian pills were analyzed to determine the concentration, bioaccessibility (arsenic fraction soluble in the human gastrointestinal system) and chemical form (speciation) of arsenic. Arsenic excretion in urine (including speciation) and facial hair were studied after a one-time ingestion. The pills contained arsenic in the form of realgar, and although the total arsenic that was present in a single pill was high (28 mg), the low bioaccessibility of this form of arsenic predicted that only 4% of it was available for absorption into the bloodstream (1 mg of arsenic per pill). The species of arsenic that were solubilized were inorganic arsenate (As(V)) and arsenite (As(III)) but DMAA and MMAA were detected in urine. Two urinary arsenic excretion peaks were observed: an initial peak several (4-8) hours after ingestion corresponding to the excretion of predominantly As(III), and a larger peak at 14 h corresponding predominantly to DMAA and MMAA. No methylated As(III) species were observed. Facial hair analysis revealed that arsenic concentrations did not increase significantly as a result of the ingestion. Arsenic is incompletely soluble under human gastrointestinal conditions, and is metabolized from the inorganic to organic forms found in urine. Bioaccessible arsenic is comparable to the quantity excreted. Facial hair as a bio-indicator should be further tested

  13. Long term retention and excretion of 201Tl in a patient after myocardial perfusion imaging

    201Tl is widely used in nuclear medicine to carry out myocardial perfusion imaging (MPI). However, very limited data is available on long-term distribution in the body, excretion and corresponding dose. In this study we performed a 2 month follow-up of a patient who underwent MPI, by urine analysis and in vivo measurements. The biological half-life of thallium was consequently estimated to be 11.6-27 d, which is in partial agreement with previous studies. We also estimated excretion and retention of 200Tl, 201Tl and 202Tl isotopes using the biokinetic parameters from ICRP publication 53 and compared the forecast result with actual measurements. The latter demonstrated a higher urinary excretion and a higher body retention than what was expected. Our results therefore suggest that the long-term retention and consequently the effective dose coefficient for 201Tl considered in ICRP publications 53 and 80 may be slightly underestimated. (authors)

  14. Long term retention and excretion of 201Tl in a patient after myocardial perfusion imaging.

    Blanchardon, E; Challeton-de Vathaire, C; Boisson, P; Célier, D; Martin, J-C; Cassot, S; Herbelet, G; Franck, D; Jourdain, J R; Biau, A

    2005-01-01

    201Tl is widely used in nuclear medicine to carry out myocardial perfusion imaging (MPI). However, very limited data is available on long-term distribution in the body, excretion and corresponding dose. In this study we performed a 2 month follow-up of a patient who underwent MPI, by urine analysis and in vivo measurements. The biological half-life of thallium was consequently estimated to be 11.6-27 d, which is in partial agreement with previous studies. We also estimated excretion and retention of 200Tl, 201Tl and 202Tl isotopes using the biokinetic parameters from ICRP publication 53 and compared the forecast result with actual measurements. The latter demonstrated a higher urinary excretion and a higher body retention than what was expected. Our results therefore suggest that the long-term retention and consequently the effective dose coefficient for 201Tl considered in ICRP publications 53 and 80 may be slightly underestimated. PMID:15671052

  15. Effect of total pressure on the absorption line blackbody distribution function and radiative transfer in H2O, CO2, and CO

    The absorption spectrum has been generated for H2O, CO2, and CO at total pressures varying from 0.1 to 50 atm using the HITEMP 2010 spectroscopic database. From these spectra the absorption line blackbody distribution function (ALBDF) has been calculated at variable total pressure in order to understand the importance of accounting for pressure changes on this parameter. The ALBDF is used in the SLW solution method to the radiative transfer equation. ALBDF data for H2O, CO2, and CO are presented, revealing a shift in the ALBDF to lower values as total pressure increases. This shift is weaker at high temperature. The shift due to increase in mole fraction of H2O and CO2 was shown to be modest, and similar at different pressures. The ALBDF was shown to become less smooth as pressure increases. Total emissivity calculations are presented for variable total pressure, and it is seen that pressure changes account for a significant change in total emissivity. Total radiative flux and radiative flux divergence were calculated from line-by-line spectral integrations for one-dimensional layers of constant length and constant mass cases, showing that total pressure changes result in a significant impact on radiative transfer in a layer of gas. Radiative flux exiting a layer of gas can change by more than a factor of four over the pressure range investigated when the pressure change is the only variable considered. - Highlights: • The absorption spectrum is generated for H2O, CO2, and CO. • Temperature range is 400–3000 K, total pressure range from 0.1 atm to 50 atm. • The ALBDF is generated from the absorption spectrum. • The ALBDF is smoother, and decreases as total pressure is increased. • Pressure effect on radiative transfer is explored from line-by-line calculations

  16. Effect of multi-effect triazole on absorption of phosphorus and nitrogen and distribution of 14CO2-assimilates in rape plant

    By using tracer technique, the effects of Multi-Effect Triazole (MET) on uptake of 32P, 15N and distribution of 14CO2-assimilates in rape plant were studied. The experimental results showed that the foliar spraying of MET with the concentration of 150 ppm in three leaves stage could significantly increase 32P uptake by 75.34%∼101.08%, the utilization rate of base fertilizer 15NH4HCO3 by 9.10%. And the rate of photosynthesis increased by 7.44%∼31.40% in seedling stage, by 47.74% in initial flowering stage and by 47.93% in mature stage. The regulation effects of MET on distribution of 15N absorbed and 14CO2-assimilates were shown by increasing absorption of 15N and assimilates in seeds of rape plant

  17. Some factors influencing the absorption, retention and elimination of ruthenium

    The radioactive isotopes of ruthenium, Ru103 (t1/2 = 40 d) and Ru106(t1/2 = 1 yr), are formed in relatively high yield as a result of nuclear fission of U235. There is almost no information on the metabolism of ruthenium by man and the following considerations are based on investigations with rats and rabbits. The nature and extent of the hazard from radioruthenium will depend not only on the circumstances of contamination but also on the physical and chemical state of the ruthenium; Ru106 administered orally as the dioxide is absorbed from the gastro-intestinal tract to a negligible extent when it is in a particulate form with carrier present but when given as a colloid in the absence of carrier, uptake is similar to that which follows administration of the chloride (3-5%). Nitrato-derivatives of nitrosyl ruthenium may be absorbed to an even greater extent (an average of 13% is absorbed by rabbits). Absorption by rats, which are not fasted, is complete within one hour of an intragastric dose. The limited period of absorption may be explained in terms of the rate of gastric emptying and combination of ruthenium with the contents of the gut. When rats are fasted overnight before the ruthenium is administered, absorption is increased threefold-and continues over a longer period. Nitrato derivatives of nitrosyl-ruthenium, in contrast to other compounds tested, react with the wall of the upper small intestine where up to 20% of an oral dose may be retained for several hours. Although the chemical state of ruthenium influences the degree of absorption, the subsequent distribution is not greatly affected. Approximately half of the absorbed ruthenium is excreted in the urine during the first 24 h. After one month, 5 to 20% of the absorbed fraction is retained with a long biological half-life. The ruthenium is distributed throughout the body with the concentrations in the various organs seldem differing by a factor of more than five, though the distribution within a single

  18. The distribution of 35S-sulfadiazine and 14C-trimethoprim in rainbow trout, Salmo gairdneri

    The distribution of 35S-labelled sulfadiazine and 14C-labelled trimethoprim was studied in rainbow trout by use of whole body autoradiography and liquid scintillation. As compared to mammals, gastrointestinal absorption and elimination were slow. Accumulation in the skin and the uveal tract of the eye was observed for both drugs tested. The results also indicated that the bile was an important route of excretion. Considerable radioactivity was still present in the skin at 144 hr. survival time. (author)

  19. Excretion pathways and ruminal disappearance of glyphosate and its degradation product aminomethylphosphonic acid in dairy cows.

    von Soosten, D; Meyer, U; Hüther, L; Dänicke, S; Lahrssen-Wiederholt, M; Schafft, H; Spolders, M; Breves, G

    2016-07-01

    From 6 balance experiments with total collection of feces and urine, samples were obtained to investigate the excretion pathways of glyphosate (GLY) in lactating dairy cows. Each experiment lasted for 26d. The first 21d served for adaptation to the diet, and during the remaining 5d collection of total feces and urine was conducted. Dry matter intake and milk yield were recorded daily and milk and feed samples were taken during the sampling periods. In 2 of the 6 experiments, at the sampling period for feces and urine, duodenal contents were collected for 5d. Cows were equipped with cannulas at the dorsal sac of the rumen and the proximal duodenum. Duodenal contents were collected every 2h over 5 consecutive days. The daily duodenal dry matter flow was measured by using chromium oxide as a volume marker. All samples (feed, feces, urine, milk and duodenal contents were analyzed for GLY and aminomethylphosphonic acid (AMPA). Overall, across the 6 experiments (n=32) the range of GLY intake was 0.08 to 6.67mg/d. The main proportion (61±11%; ±SD) of consumed GLY was excreted with feces; whereas excretion by urine was 8±3% of GLY intake. Elimination via milk was negligible. The GLY concentrations above the limit of quantification were not detected in any of the milk samples. A potential ruminal degradation of GLY to AMPA was derived from daily duodenal GLY flow. The apparent ruminal disappearance of GLY intake was 36 and 6%. In conclusion, the results of the present study indicate that the gastrointestinal absorption of GLY is of minor importance and fecal excretion represents the major excretion pathway. A degradation of GLY to AMPA by rumen microbes or a possible retention in the body has to be taken into account. PMID:27108173

  20. Comparison of urinary excretion of radon from the human body before and after radon bath therapy

    Theoretically, the human body absorbs radon through the lungs and the skin and excretes it through the lungs and the excretory organs during radon bath therapy. To check this theory, the radon concentrations in urine samples were compared before and after radon bath therapy. During the therapy, the geometric mean (GM) and the geometric standard deviation of the radon concentration in air and in the bath water were 979 Bq m-3, 1.58 and 73.6 Bq dm-3, 1.1, respectively. Since radon was detected in each urine sample (GM around 3.0 Bq dm-3), urinary excretion of radon was confirmed. The results of this study can neither reject nor confirm the hypothesis of radon absorption through the skin. A 15 times higher increment of inhaled radon level did not cause significant changes in radon of urine samples. (authors)

  1. Urinary growth hormone excretion in acromegaly

    Main, K M; Lindholm, J; Vandeweghe, M;

    1993-01-01

    The biochemical assessment of disease activity in acromegaly still presents a problem, especially in treated patients with mild clinical symptoms. We therefore examined the diagnostic value of the measurement of urinary growth hormone (GH) excretion in seventy unselected patients with acromegaly of...... different activity by comparing it to serum GH, serum insulin-like growth factor I (IGF-I) and clinical activity. There were highly significant, positive correlations between urinary GH and serum GH, serum IGF-I as well as clinical activity score (p < 0.00005), although some overlap between the groups was...

  2. Excretion of Δ9-Tetrahydrocannabinol in Sweat

    Huestis, Marilyn A.; Scheidweiler, Karl B.; Saito, Takeshi; Fortner, Neil; Abraham, Tsadik; Gustafson, Richard A.; Smith, Michael L.

    2007-01-01

    Sweat testing is a noninvasive technique for monitoring drug exposure over a 7-day period in treatment, criminal justice, and employment settings. We evaluated Δ9-tetrahydrocannabinol (THC) excretion in 11 daily cannabis users after cessation of drug use. PharmChek® sweat patches worn for 7 days were analyzed for THC by gas chromatography-mass spectrometry (GC/MS). The limit of quantification (LOQ) for the method was 0.4 ng THC/patch. Sweat patches worn the first week of continuously monitore...

  3. Excretion of urinary cadmium, copper, and zinc in cadmium-exposed and nonexposed subjects, with special reference to urinary excretion of beta2-microglobulin and metallothionein.

    Nakajima, Maki; Kobayashi, Etsuko; Suwazono, Yasushi; Uetani, Mirei; Oishi, Mitsuhiro; Inaba, Takeya; Kido, Teruhiko; Shaikh, Zahir A; Nogawa, Koji

    2005-01-01

    The objectives of this study were to examine the association between urinary excretion of cadmium (U-Cd), copper (U-Cu), and zinc (U-Zn) and the severity of two different indicators of renal toxicity (urinary excretion of beta2-microglobulin [U-beta2-MG] and metallothionein [U-MT]) in Cd-exposed subjects compared to controls, and to assess the physiologic mechanisms by which the exposure to environmental Cd affects U-Cd, U-Cu, and U-Zn. The target population included 3508 Cd-exposed and 294 nonexposed participants who received a health survey conducted among the population of the Kakehashi River basin. Increases of U-Cd, U-beta2-MG, and U-MT in the Cd-exposed population were observed relative to excretion of these substances in controls. Regression analysis using a general linear model revealed that the correlations between U-Cd or U-Cu, and U-beta2-MG and between U-Cd, U-Cu or U-Zn, and U-MT were statistically significant in both sexes, but the correlation between U-Zn and U-beta2-MG excretion was significant only in men. These results suggest U-Cd and U-Cu is affected by dysfunction in renal tubular absorption (indicated by U-beta2-MG), whereas not only U-Cd and U-Cu but also U-Zn appear to be a function of renal cellular desquamation (indicated by U-MT). PMID:16327056

  4. The H + OCS hot atom reaction - CO state distributions and translational energy from time-resolved infrared absorption spectroscopy

    Nickolaisen, Scott L.; Cartland, Harry E.

    1993-01-01

    Time-resolved infrared diode laser spectroscopy has been used to probe CO internal and translational excitation from the reaction of hot H atoms with OCS. Product distributions should be strongly biased toward the maximum 1.4 eV collision energy obtained from 278 nm pulsed photolysis of HI. Rotations and vibrations are both colder than predicted by statistical density of states theory, as evidenced by large positive surprisal parameters. The bias against rotation is stronger than that against vibration, with measurable population as high as v = 4. The average CO internal excitation is 1920/cm, accounting for only 13 percent of the available energy. Of the energy balance, time-resolved sub-Doppler line shape measurements show that more than 38 percent appears as relative translation of the separating CO and SH fragments. Studies of the relaxation kinetics indicate that some rotational energy transfer occurs on the time scale of our measurements, but the distributions do not relax sufficiently to alter our conclusions. Vibrational distributions are nascent, though vibrational relaxation of excited CO is unusually fast in the OCS bath, with rates approaching 3 percent of gas kinetic for v = 1.

  5. Late excretion of plutonium following acquisition of known amounts

    The urinary and fecal excretion rates of plutonium 10,000 days after intravenous injection of known amounts are compared with the predictions of various models. Both Langham's and Durbin's equations underestimated the urinary excretion by about an order of magnitude; the observed fecal excretion rates were also higher than the predictions. The total excretion rate predicted by the ICRP model was in quite good agreement with the observed rate, but it overestimated it at early times (239Pu of former Manhattan Project plutonium workers, as calculated from the measured urinary excretion an application of Langham's equation. In one of these subjects the urinary excretion rate started to increase at about 6000 days, reached a maximum at about 9500 days, and declined for the next 2700 days

  6. Gastrointestinal absorption of uranium in man

    A method has been established for determining the fractional absorption of uranium directly in man. Measurements are made of the urinary excretion rates of uranium for individuals whose drinking water has a high 234U to 238U activity ratio and is the primary source of 234U in their diets. For two individuals, the values obtained for the fractional absorption of 234U were 0.004 and 0.006. The values obtained for the fractional absorption of 238U, using a literature value for the 238U intake from food, were 0.008 and 0.015. The present ICRP value is 0.20. 7 references, 1 table

  7. NONLINEAR COLOR-METALLICITY RELATIONS OF GLOBULAR CLUSTERS. V. NONLINEAR ABSORPTION-LINE INDEX VERSUS METALLICITY RELATIONS AND BIMODAL INDEX DISTRIBUTIONS OF M31 GLOBULAR CLUSTERS

    Recent spectroscopy on the globular cluster (GC) system of M31 with unprecedented precision witnessed a clear bimodality in absorption-line index distributions of old GCs. Such division of extragalactic GCs, so far asserted mainly by photometric color bimodality, has been viewed as the presence of merely two distinct metallicity subgroups within individual galaxies and forms a critical backbone of various galaxy formation theories. Given that spectroscopy is a more detailed probe into stellar population than photometry, the discovery of index bimodality may point to the very existence of dual GC populations. However, here we show that the observed spectroscopic dichotomy of M31 GCs emerges due to the nonlinear nature of metallicity-to-index conversion and thus one does not necessarily have to invoke two separate GC subsystems. We take this as a close analogy to the recent view that metallicity-color nonlinearity is primarily responsible for observed GC color bimodality. We also demonstrate that the metallicity-sensitive magnesium line displays non-negligible metallicity-index nonlinearity and Balmer lines show rather strong nonlinearity. This gives rise to bimodal index distributions, which are routinely interpreted as bimodal metallicity distributions, not considering metallicity-index nonlinearity. Our findings give a new insight into the constitution of M31's GC system, which could change much of the current thought on the formation of GC systems and their host galaxies.

  8. Potassium excretion during antinatriuresis: perspective from a distal nephron model

    Weinstein, Alan M.

    2011-01-01

    Renal excretion of Na+ and K+ must be regulated independently within the distal nephron, but is complicated by the fact that changing excretion of one solute requires adjustments in the transport of both. It is long known that hypovolemia increases Na+ reabsorption while impairing K+ excretion, even when distal Na+ delivery is little changed. Renewed interest in this micropuncture observation came with identification of the molecular defects underlying familial hyperkalemic hypertension (FHH)...

  9. Lorry drivers' work stress evaluated by catecholamines excreted in urine.

    van der Beek, A J; Meijman, T.F; Frings-Dresen, M. H.; Kuiper, J I; Kuiper, S.

    1995-01-01

    OBJECTIVES--To evaluate lorry drivers' work stress by measurement of adrenaline and noradrenaline excreted in the urine, and to find out which factors in their working situation are related to the excretion rates of these catecholamines. METHODS--The urinary excretion of adrenaline and noradrenaline of 32 lorry drivers, who also had loading and unloading activities to perform, was studied for one working day and one rest day. Each driver was asked to provide six urine samples on both days. RE...

  10. Ammonium excretion and oxygen respiration of tropical copepods and euphausiids exposed to oxygen minimum zone conditions

    Kiko, Rainer; Hauss, Helena; Buchholz, Friedrich; Melzner, Frank

    2016-04-01

    Calanoid copepods and euphausiids are key components of marine zooplankton communities worldwide. Most euphausiids and several copepod species perform diel vertical migrations (DVMs) that contribute to the export of particulate and dissolved matter to midwater depths. In vast areas of the global ocean, and in particular in the eastern tropical Atlantic and Pacific, the daytime distribution depth of many migrating organisms corresponds to the core of the oxygen minimum zone (OMZ). At depth, the animals experience reduced temperature and oxygen partial pressure (pO2) and an increased carbon dioxide partial pressure (pCO2) compared to their near-surface nighttime habitat. Although it is well known that low oxygen levels can inhibit respiratory activity, the respiration response of tropical copepods and euphausiids to relevant pCO2, pO2, and temperature conditions remains poorly parameterized. Further, the regulation of ammonium excretion at OMZ conditions is generally not well understood. It was recently estimated that DVM-mediated ammonium supply could fuel bacterial anaerobic ammonium oxidation - a major loss process for fixed nitrogen in the ocean considerably. These estimates were based on the implicit assumption that hypoxia or anoxia in combination with hypercapnia (elevated pCO2) does not result in a down-regulation of ammonium excretion. We exposed calanoid copepods from the Eastern Tropical North Atlantic (ETNA; Undinula vulgaris and Pleuromamma abdominalis) and euphausiids from the Eastern Tropical South Pacific (ETSP; Euphausia mucronata) and the ETNA (Euphausia gibboides) to different temperatures, carbon dioxide and oxygen levels to study their survival, respiration and excretion rates at these conditions. An increase in temperature by 10 °C led to an approximately 2-fold increase of the respiration and excretion rates of U. vulgaris (Q10, respiration = 1.4; Q10, NH4-excretion = 1.6), P. abdominalis (Q10, respiration = 2.0; Q10, NH4-excretion = 2.4) and

  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. Absorption and tissue distribution of radioactivity in mussels (Mytilus Galloprovincialis) exposed to low concentrations of 14C-polychlorinated biphenyl

    Mussels (Mytilus galloprovincialis) were exposed for 144 h to an isomeric 14C polychlorinated biphenyl (PCB) mixture at an initial concentration of 4.6 μg l-1. Animals were sampled after 6, 12, 24, 72 and 144 h of exposure for sex differences in PCB tissue distribution. PCB was readily absorbed within 12 h and then slowly eliminated from the body with a biological half-time of 209 h. No sexual differences were observed except with mussels sampled at 12 h, where 14C activity was significantly higher (P14C activity measured in gills appeared to be related to the PCB water concentration. 14 refs.; 3 figs.; 1 table

  13. Tunable diode laser absorption spectroscopy-based tomography system for on-line monitoring of two-dimensional distributions of temperature and H2O mole fraction

    To monitor two-dimensional (2D) distributions of temperature and H2O mole fraction, an on-line tomography system based on tunable diode laser absorption spectroscopy (TDLAS) was developed. To the best of the authors’ knowledge, this is the first report on a multi-view TDLAS-based system for simultaneous tomographic visualization of temperature and H2O mole fraction in real time. The system consists of two distributed feedback (DFB) laser diodes, a tomographic sensor, electronic circuits, and a computer. The central frequencies of the two DFB laser diodes are at 7444.36 cm−1 (1343.3 nm) and 7185.6 cm−1 (1391.67 nm), respectively. The tomographic sensor is used to generate fan-beam illumination from five views and to produce 60 ray measurements. The electronic circuits not only provide stable temperature and precise current controlling signals for the laser diodes but also can accurately sample the transmitted laser intensities and extract integrated absorbances in real time. Finally, the integrated absorbances are transferred to the computer, in which the 2D distributions of temperature and H2O mole fraction are reconstructed by using a modified Landweber algorithm. In the experiments, the TDLAS-based tomography system was validated by using asymmetric premixed flames with fixed and time-varying equivalent ratios, respectively. The results demonstrate that the system is able to reconstruct the profiles of the 2D distributions of temperature and H2O mole fraction of the flame and effectively capture the dynamics of the combustion process, which exhibits good potential for flame monitoring and on-line combustion diagnosis

  14. Tunable diode laser absorption spectroscopy-based tomography system for on-line monitoring of two-dimensional distributions of temperature and H2O mole fraction

    Xu, Lijun; Liu, Chang; Jing, Wenyang; Cao, Zhang; Xue, Xin; Lin, Yuzhen

    2016-01-01

    To monitor two-dimensional (2D) distributions of temperature and H2O mole fraction, an on-line tomography system based on tunable diode laser absorption spectroscopy (TDLAS) was developed. To the best of the authors' knowledge, this is the first report on a multi-view TDLAS-based system for simultaneous tomographic visualization of temperature and H2O mole fraction in real time. The system consists of two distributed feedback (DFB) laser diodes, a tomographic sensor, electronic circuits, and a computer. The central frequencies of the two DFB laser diodes are at 7444.36 cm-1 (1343.3 nm) and 7185.6 cm-1 (1391.67 nm), respectively. The tomographic sensor is used to generate fan-beam illumination from five views and to produce 60 ray measurements. The electronic circuits not only provide stable temperature and precise current controlling signals for the laser diodes but also can accurately sample the transmitted laser intensities and extract integrated absorbances in real time. Finally, the integrated absorbances are transferred to the computer, in which the 2D distributions of temperature and H2O mole fraction are reconstructed by using a modified Landweber algorithm. In the experiments, the TDLAS-based tomography system was validated by using asymmetric premixed flames with fixed and time-varying equivalent ratios, respectively. The results demonstrate that the system is able to reconstruct the profiles of the 2D distributions of temperature and H2O mole fraction of the flame and effectively capture the dynamics of the combustion process, which exhibits good potential for flame monitoring and on-line combustion diagnosis.

  15. Study of Absorption and Distribution of Mercury in Nerium Oleander L. on Banks of the Valdeazogues River (Chillon Station- Ciudad Real)

    The main objective of this study is to determine the absorption and distribution of mercury in oleander (Nerium oleander L.) in the Valdeazogues river, located within the mining regions of Almaden (Ciudad Real). The results show that total mercury concentrations in soil range from 116,7 ±24,3 to 350,9 ± 68,6 mg kg-1 of Hg, but the readily available fraction (soluble + exchangeable) is very low (from 0,013 to 0,017 ± 0,257 ± 0,000 mg Hg kg-1: less than 0,16% of the total concentration of mercury measured directly on the soil sample).The distribution of mercury absorbed by N. oleander is not homogeneous throughout the aerial part. In general, the concentration is significantly higher in the leaves followed by stems and fruits. According to the results, although the concentration of mercury in the plant is not very high (Leaves: 0,282 ±0,014-1,022 ± 0,110 mg Kg-1; Stems: 0,087 ± 0,011-0,354 ± 0,046 mg Kg-1; Fruits: 0,030 ± 0,003-0,077 ± 0,009 mg Kg-1), oleander has a number of characteristics (high biomass, toxicity, non-edible) that could turn into a future candidate as phyto extraction of mercury in decontamination processes. (Author) 67 refs.

  16. Improved multi-element measurement of absorption via the fecal monitoring technique

    The fecal monitoring technique for measuring the absorption of Mn, Se and Fe was studied in eight piglets using high resolution gamma spectrometry. Four day old piglets were fed a complete liquid diet for five days prior to the administration of an isotope dose (75Se, 54Mn, 59Fe) equilibrated with the milk feeding. 51CrCl3 was used as a fecal marker. Subsequently stool and urine samples were collected daily for 15-21 days. Following counting, the % fecal excretion of the administered dose was calculated. As 0 to 33% of the administered 51CrCl3 was absorbed this fecal marker is inappropriate for piglets. Results indicate that endogenous excretion for each of the isotopes was not constant but decreased exponentially with time. An improved method for calculating the endogenous excretion was therefore developed. This method is based on the pattern of endogenous excretion in comparable piglets injected intravenously with the same isotopes, and on the level of endogenous excretion in the orally fed animals in the post-absorptive phase of excretion. These findings have important implications for the estimation of endogenous excretion in future fecal monitoring absorption studies. Previous results using the latter technique have frequently underestimated true absorption

  17. Can the excretion of metabolites by bacteria be manipulated?

    Konings, Wil N.; Poolman, Bert; Driessen, Arnold J.M.

    1992-01-01

    Bacteria can release metabolites into the environment by various mechanisms. Excretion may occur by passive diffusion or by the reversal of the uptake process when the internal concentration of the metabolite exceeds the thermodynamic equilibrium level. In other cases, solutes are excreted against t

  18. A rapid method to derive horizontal distributions of trace gases and aerosols near the surface using multi-axis differential optical absorption spectroscopy

    Y. Wang

    2013-09-01

    Full Text Available We apply a novel experimental procedure for the rapid measurement of the average volume mixing ratios (VMRs and horizontal distributions of trace gases such as NO2, SO2, and HCHO in the boundary layer, which was recently suggested by Sinreich et al. (2013. The method is based on two-dimensional scanning multi-axis differential optical absorption spectroscopy (MAX-DOAS. It makes use of two facts (Sinreich et al. 2013: First, the light path for observations at 1° elevation angle traverses mainly air masses located close to the ground (typically 4. Thus, the average value of the trace gas VMR in the atmospheric layer between the surface and the altitude, for which this observation was sensitive, can be calculated. Compared to the originally proposed method, we introduce several important modifications and improvements: We apply the method only to measurements at 1° elevation angles, for which the uncertainties are especially small. Using only 1 elevation angle also allows an increased temporal resolution. We apply correction factors (and their uncertainties as function of the simultaneously modelled O4 absorption. In this way the correction factors can be directly determined according to the measured O4 dAMF. Finally, the method is extended to trace gases analysed at other wavelengths and also to the retrieval of the aerosol extinction. Depending on the atmospheric visibility, the typical uncertainty of the results ranges from about 15 to 30%. We apply the rapid method to observations of a newly developed ground-based multifunctional passive differential optical absorption spectroscopy (GM-DOAS instrument in the north-west outskirt near Hefei City in China. We report NO2, SO2, and HCHO VMRs and aerosol extinction for four azimuth angles and compare these results with those from simultaneous long-path DOAS observations. Good agreement is found (squares of the correlation coefficients for NO2, SO2, and HCHO were 0.92, 0.84, and 0.59, respectively

  19. Development of a physiologically-based computational kidney model to describe the renal excretion of hydrophilic agents in rats

    ChristophNiederalt; PhilippLengsfeld; KarinaClaaßen; RolfBurghaus; MatthiasBräutigam; HubertusPietsch

    2013-01-01

    A physiologically-based kidney model was developed to analyze the renal excretion and kidney exposure of hydrophilic agents, in particular contrast media, in rats. In order to study the influence of osmolality and viscosity changes, the model mechanistically represents urine concentration by water re-absorption in different segments of kidney tubules and viscosity dependent tubular fluid flow. The model was established using experimental data on the physiological steady state without admin...

  20. Absorption and metabolism of triclosan after application to the skin of B6C3F1 mice.

    Fang, Jia-Long; Vanlandingham, Michelle; Gamboa da Costa, Gonçalo; Beland, Frederick A

    2016-05-01

    Triclosan is used as an antimicrobial agent in personal care products, household items, medical devices, and clinical settings. Humans can receive lifelong exposures to triclosan; however, data on the toxicity and carcinogenicity after topical application are lacking. This study determined the absorption, distribution, metabolism, and excretion of triclosan after application to the skin of B6C3F1 mice. [(14) C(U)]triclosan (10 or 100 mg triclosan/kg body weight) was administered topically to mice in two separate experiments: a vehicle selection experiment using propylene glycol, ethanol, and a generic cosmetic cream, and a toxicokinetic experiment. Mice were killed up to 72 h after triclosan administration, and excreta and tissues were analyzed for radioactivity. Ethanol had the best properties of the vehicles evaluated. Maximum absorption was obtained at approximately 12 h after dosing. Radioactivity appeared in the excreta and in all tissues examined, with the highest levels in the gall bladder and the lowest levels in the brain. Triclosan was metabolized to triclosan sulfate, triclosan glucuronide, 2,4-dichlorophenol, and hydroxytriclosan. The metabolite profile was tissue-dependent and the predominant route of excretion was fecal. The AUC0-∞ and the Cmax of plasma and liver in females were greater than those in males. Slightly lower absorption was observed in mice with Elizabethan collars. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 609-623, 2016. PMID:25410937

  1. Absorption and distribution of xenobiotics.

    Standaert, F G

    1988-01-01

    Extrapolation of pharmacokinetic data between species has been simplified by the advent of more sensitive methods of analysis of chemicals in body tissues and by the capability of inexpensive computers to perform complex calculations. These new methods enable investigators to observe the rates at which target tissues reach equilibrium in different species and to develop mathematical models of these processes. The evaluation of physiological pharmacokinetics from classical or compartmental kin...

  2. A rapid method to derive horizontal distributions of trace gases and aerosols near the surface using multi-axis differential optical absorption spectroscopy

    Wang, Y.; Li, A.; Xie, P. H.; Wagner, T.; Chen, H.; Liu, W. Q.; Liu, J. G.

    2014-06-01

    We apply a novel experimental procedure for the rapid measurement of the average volume mixing ratios (VMRs) and horizontal distributions of trace gases such as NO2, SO2, and HCHO in the boundary layer, which was recently suggested by Sinreich et al. (2013). The method is based on two-dimensional scanning multi-axis differential optical absorption spectroscopy (MAX-DOAS). It makes use of two facts (Sinreich et al., 2013): first, the light path for observations at 1° elevation angle traverses mainly air masses located close to the ground (typically DOAS) instrument in the north-west outskirts near Hefei in China. We report NO2, SO2, and HCHO VMRs and aerosol extinction for four azimuth angles and compare these results with those from simultaneous long-path DOAS observations. Good agreement is found (squares of the correlation coefficients for NO2, SO2, and HCHO were 0.92, 0.85, and 0.60, respectively), verifying the reliability of this novel method. Similar agreement is found for the comparison of the aerosol extinction with results from visibility meters. Future studies may conduct measurements using a larger number of azimuth angles to increase the spatial resolution.

  3. Urinary growth hormone excretion in 657 healthy children and adults

    Main, K; Philips, M; Jørgensen, M;

    1991-01-01

    Urinary growth hormone (u-GH) excretion was measured in 547 healthy children and 110 adults by ELISA with a detection limit of 1.1 ng/l u-GH after prior concentration of the urine samples (20- to 30-fold). u-GH excretion values were significantly dependent on the pubertal stage (p less than 0.......0001) with maximum values in Tanner stage 3 for girls and 4 for boys. This corresponded to a peak in u-GH excretion between 11.5-14.5 years in girls and 12.5-16 years in boys. Additionally, u-GH excretion in adults was significantly higher than in prepubertal children (p less than 0.001). The day/night ratio...... of u-GH excretion (pg/h) was significantly higher in females than in males (p less than 0.01). In Tanner stages 1-4, u-GH excretion during the day was lower than that at night, whereas the opposite was true in late puberty and in adult women. The interindividual variation of u-GH excretion within the...

  4. Excretion of biliary compounds during intrauterine life

    Rocio IR Macias; Jose JG Marin; Maria A Serrano

    2009-01-01

    In adults, the hepatobiliary system, together with thekidney, constitute the main routes for the eliminationof several endogenous and xenobiotic compounds intobile and urine, respectively. However, during intrauterinelife the biliary route of excretion for cholephiliccompounds, such as bile acids and biliary pigments, isvery poor. Although very early in pregnancy the fetal liver produces bile acids, bilirubin and biliverdin, these compounds cannot be efficiently eliminated by the fetal hepatobiliary system, owing to the immaturity of the excretory machinery in the fetal liver. Therefore, the potentially harmful accumulation of cholephilic compounds in the fetus is prevented by their elimination across the placenta. Owing to the presence of detoxifying enzymes and specific transport systems at different locations of the placental barrier, such as the endothelial cells of chorionic vessels and trophoblast cells, this organ plays an important role in the hepatobiliary-like function during intrauterine life. The relevance of this excretory function in normal fetal physiology is evident in situations where high concentrations of biliary compounds are accumulated in the mother. This may result in oxidative stress and apoptosis, mainly in the placenta and fetal liver, which might affect normal fetal development and challenge the fate of the pregnancy. The present article reviews current knowledge of the mechanisms underlying the hepatobiliary function of the fetal-placental unit and the repercussions of several pathological conditions on this tandem.

  5. Absorption and Metabolism of Xanthophylls

    Eiichi Kotake-Nara

    2011-06-01

    Full Text Available Dietary carotenoids, especially xanthophylls, have attracted significant attention because of their characteristic biological activities, including anti-allergic, anti-cancer, and anti-obese actions. Although no less than forty carotenoids are ingested under usual dietary habits, only six carotenoids and their metabolites have been found in human tissues, suggesting selectivity in the intestinal absorption of carotenoids. Recently, facilitated diffusion in addition to simple diffusion has been reported to mediate the intestinal absorption of carotenoids in mammals. The selective absorption of carotenoids may be caused by uptake to the intestinal epithelia by the facilitated diffusion and an unknown excretion to intestinal lumen. It is well known that β-carotene can be metabolized to vitamin A after intestinal absorption of carotenoids, but little is known about the metabolic transformation of non provitamin A xanthophylls. The enzymatic oxidation of the secondary hydroxyl group leading to keto-carotenoids would occur as a common pathway of xanthophyll metabolism in mammals. This paper reviews the absorption and metabolism of xanthophylls by introducing recent advances in this field.

  6. Absorption studies

    Absorption studies were once quite popular but hardly anyone does them these days. It is easier to estimate the blood level of the nutrient directly by radioimmunoassay (RIA). However, the information obtained by estimating the blood levels of the nutrients is not the same that can be obtained from the absorption studies. Absorption studies are primarily done to find out whether some of the essential nutrients are absorbed from the gut or not and if they are absorbed, to determine how much is being absorbed. In the advanced countries, these tests were mostly done to detect pernicious anaemia where vitamin B12 is not absorbed because of the lack of the intrinsic factor in the stomach. In the tropical countries, ''malabsorption syndrome'' is quire common. In this condition, several nutrients like fat, folic acid and vitamin B12 are not absorbed. It is possible to study absorption of these nutrients by radioisotopic absorption studies

  7. Dietary intake and urinary excretion of lignans in Finnish men

    Nurmi, Tarja; Mursu, Jaakko; Peñalvo, José L;

    2010-01-01

    Finnish men consuming their habitual omnivorous diet, and measured the 24 h urinary excretion of plant and enterolignans to compare the intake and metabolism. Dietary determinants of lignan intake and their urinary excretion were also determined. The mean intake of lignans was 1224 (sd 539) mug/d, of...... only 4 % by the intake of lariciresinol. Although the assessed intake of lignans corresponded well with the urinary excretion of lignans, the enterolactone production in the human body depended more on the dietary sources of lignans than the absolute intake of lignans....

  8. Oxyproline excretion with urine in rats following EDTA salts injection

    Excretion of oxyproline and calcium with urine in rats following calcium-binding chelates (Na2H3 EDTA, CaNa2 EDTA) injected into blood was studied. It was shown that excretion of oxyproline with urine in intact rats exceeds normal values of this index (0.07 mkmol/h) by 2-2.6 fold. Highly reliable correlation was stated between excretion rate of oxyproline and calcium with urine in intact rats (correlation coefficient-0.9). A decrease in oxyproline content in urine is observed in irradiated animals. 5 refs.; 3 tabs

  9. Dietary intake and urinary excretion of lignans in Finnish men

    Nurmi, Tarja; Mursu, Jaakko; Peñalvo, José L; Poulsen, Henrik E; Voutilainen, Sari

    2010-01-01

    of plant lignans was explained 14 % by the intake of rye products and intake of coffee, and consequently 3-7 % by the intakeof water-insoluble fibre. The urinary excretion of enterolactone was explained 11 % by the intake of vegetables and rye products, 14 % by the intake of water-soluble fibre and...... which lariciresinol and pinoresinol covered 78 %. Almost half (47 %) of the intake of lignans was explained by the intake of rye products, berries, coffee, tea and roots. The urinary excretion of plant lignans corresponded to 17 % and enterolignans to 92 % of the intake of lignans. The urinary excretion...

  10. Effects of xylitol on the absorption of /sup 203/Pb in mice and cockerels

    Mykkaenen, H.M.; Salminen, S.J.

    1986-07-01

    Earlier studies have indicated that xylitol may increase the absorption and urinary excretion of dietary oxalate. It has also been indicated that xylitol increases the absorption of calcium. Intestinal absorption of lead, a divalent contaminant in the diet, is in many respects similar to that of calcium. The purpose of this study was to evaluate the effects of xylitol on the intestinal absorption of lead using two different approaches: the in situ ligated intestinal loop technique in cockerels and gastric gavage in mice.

  11. Effects of xylitol on the absorption of 203Pb in mice and cockerels

    Earlier studies have indicated that xylitol may increase the absorption and urinary excretion of dietary oxalate. It has also been indicated that xylitol increases the absorption of calcium. Intestinal absorption of lead, a divalent contaminant in the diet, is in many respects similar to that of calcium. The purpose of this study was to evaluate the effects of xylitol on the intestinal absorption of lead using two different approaches: the in situ ligated intestinal loop technique in cockerels and gastric gavage in mice

  12. Effect of dietary supplementation of essential oils mixture on performance, eggshell quality, hatchability, and mineral excretion in quail breeders.

    Olgun, Osman; Yıldız, Alp Önder

    2014-12-01

    The main aim of this study was to investigate the effect of six different levels (0, 50, 100, 200, 400, and 600 mg/kg) of phytogenic feed additive containing a mixture essential oils from thyme, black cumin, fennel, anise and rosemary on performance, eggshell quality, reproductive traits, and mineral excretion in quail breeders. In this trial, a total of 60 male and 120 female quails, 91 days old, were randomly distributed in six experimental groups. During the 60-day experiment period, birds were fed with six treatment diets. Performances, eggshell qualities, hatchability, and mineral excretion data were evaluated at the end of the experiment. Results showed that the different dietary levels of essential oil mixture had no significant effect on performance parameters, damaged eggs, eggshell weight, fertility, hatchability of fertile eggs, hatchability of set eggs, and lead and boron excretion. On the other hand, 50 mg/kg supplementation of essential oil mixture (EOM) significantly improved egg-breaking strength and eggshell thickness, and ash, calcium, phosphorus, magnesium, manganese, zinc, and cadmium excretion was significantly depressed in quail breeders supplemented with the two higher doses (400 or 600 mg/kg) of EOM. These results concluded that supplementing diets with EOM improved egg-breaking strength and decreased excretion of minerals in breeder quails. PMID:25012208

  13. Comparative analyses of action spectra of glycolate excretion ('photorespiration') and photosynthesis in the blue-green alga Anacystis nidulans

    The action spectra were determined by measuring photosynthetic H14CO-3 -fixation and 14C-glycolate excretion to the medium during 15 min exposure to light at 15 different wavelengths in the visible region using interference filters and a 2500 W high pressure Xe lamp at a constant photon flux of about 1.51 X 1019 quanta m-2. s-1 at all wavelengths. When plotted on relative scales the action spectrum of glycolate excretion lies below that of photosynthesis at all wavelengths shorter than 517 nm. As glycolate excretion had an exponential relationship to photosynthetic rates, different methods were used to analyse for a specific blue light effect which demonstrated that the relative amount of glycolate excretion was depressed by blue light compared with that by green and red. The greatest difference was observed around 460-480 nm. However, on statistical grounds it is not permitted to draw a difference spectrum which might indicate the absorption characteristics of pigment(s) involved. A hypothesis is discussed assuming that some glycolate is consumed in an oxidation process for supply of electrons to photosystem 1 when photosystem 2 is poorly excited in the blue region of the spectrum, which was the case for Anacystis used in the present investigation. (author)

  14. Endogenous zinc excretion in relation to various levels of dietary zinc intake in the mink (Mustela vison)

    Endogenous zinc excretion was studied in adult male mink fed experimental diets for 73 d, including a collection period from d 69 to 73. Dietary zinc levels were 2.8, 26 or 121 mg/kg wet weight. In accordance with the results of a methodological study, also reported here, the animals had an intramuscular injection of 65ZnCl2 12 d before the start of the collection period. Total fecal (endogenous + unabsorbed) zinc excretion for d 69-73 in the three groups was 2.3, 20.4 and 91.0 mg. The endogenous zinc excretion was 1.3, 2.0 and 6.4 mg, corresponding to 80.8, 10.6 and 6.4% of the zinc intake. Thus, the endogenous excretion was mainly important for the zinc homeostasis at low zinc intake, whereas at high intake the homeostasis was regulated via absorption from the digestive tract. The overall conclusion of the experiment was that mink are comparable to other species (including man) in regard to mechanisms controlling zinc homeostasis

  15. Persistence of urinary excretion products of benzo(a)pyrene

    Persistence of DNA-adducts has been observed in a variety of experimental circumstances and has been suggested as one potential mechanism for explaining the long-term delay before expression of proliferative disease. In this concept, a stable DNA-adduct, which is a remnant of a prior exposure in a nondividing cell, would not express the genotoxic effect until the cells were stimulated to divide, and thus explain the long-term delay in expression of cancer. An alternative view of the observation of persistent DNA-adducts, described in this communication, is the continuing replenishment of DNA adducts by formation and turnover of these adducts from exposure to a constant supply of the ultimate carcinogenic species derived from a prior exposure. It is of interest to note that virtually all experiments where ''persistent'' adducts have been observed have been high dose exposures. During the course of experiments designed to develop improved methods for detection of DNA adducts and related derivatives derived from polynuclear aromatic hydrocarbons (PAH), we observed that there was a continuous excretion of urinary derivatives of the injected benzo(a)pyrene (BaP) beyond the initial burst of detoxification. This report describes the time dependent distribution of those derivatives in blood, urine, feces, and at the site of injection. 11 refs., 5 figs., 4 tabs

  16. Absorption and Distribution of Foliar Applied Boron in Upland Cotton%陆地棉对叶面施硼的吸收和分配

    张君; 危常州; 梁远航; 李美宁; 董鹏

    2012-01-01

    In this paper we studied the absorption and distribution of foliar applied boron in upland cotton(Gossypium hirsutum L.) in a hydroponic experiment. The results showed that both boron concentration and uptake in different cotton plant organs were the greatest in the leaves, followed by the stem, and lowest in the roots, boron absorption in the cotton plants increased significantly after foliar boron application except in roots. Compared with the control treatment, boron concentration in roots decreased by 41.9% when boron was partially applied on the leaves and by 11.2% when boron was applied to all leaves. Stalk boron concentration in the partial application treatment decreased by 5.9% compared to the control, but boron concentration in cotton leaves increased by 149.1%, significantly greater than the control treatment. In the partial application treatment, the amount of boron that was transferred to untreated leaves was only 5.2%, showing that boron absorbed by leaves can be partially transferred to conductivity organs but hardly enters other leaves. In the whole plant boron application treatment, the absorption of boron increased by 22.5% in the stalk and 203.7% in leaves.%通过水培试验结合室内分析,研究陆地棉对叶面施硼的吸收和分配.结果表明:施硼显著提高植株体内的硼含量和硼吸收量;棉花各器官硼含量及硼吸收量顺序均为叶片>茎秆>根系;与根系营养吸硼处理相比,叶面施硼后棉花的根系含硼量显著降低,其中部分叶片施硼处理的棉花根系硼含量降低了41.9%,全株叶片施硼的根系硼含量降低11.2%;部分叶片施硼后棉花茎秆硼含量比根系营养吸硼处理降低了5.9%,叶片硼含量比根系营养吸硼处理增加149.1%,硼主要停留在施硼叶片中,被转移到不施硼叶片的硼含量只占5.2%,难以通过输导组织进入其他叶片;全株叶片施硼,进入茎秆的硼素比根系营养吸硼处理增加22.5%,但

  17. Absorption and metabolism of benzoic acid in growing pigs

    Kristensen, N B; Nørgaard, J V; Wamberg, S; Engbæk, M; Fernández, J A; Zacho, H D; Poulsen, H D

    2009-01-01

    Dietary benzoic acid (BA) supplementation causes a pronounced reduction in urinary pH but only small changes in blood pH. The present study aimed to investigate the portal absorption profile, hepatic metabolism of BA, and renal excretion of hippuric acid (HA) underlying the relatively small impact...

  18. Sodium intake affects urinary albumin excretion especially in overweight subjects

    Verhave, J C; Hillege, H L; Burgerhof, J G M; Janssen, W M T; Gansevoort, R T; Navis, G J; de Zeeuw, D; de Jong, P E; Postma, Maarten

    2004-01-01

    Objectives. To examine the relationship between sodium intake and urinary albumin excretion, being an established risk marker for later cardiovascular morbidity and mortality. Design. Cross-sectional cohort study using linear regression analysis. Setting: University hospital outpatient clinic. Subje

  19. Simplified excretion functions for recent recycling biokinetic models

    Recent trends in biokinetic model development have seen the replacement of a simple, schematic one-way transfer of materials between compartments with more realistic and complex linkages, including 'recycling'. In its Publications 67 and 69, ICRP proposes the use of such models for Am, Np, Pu, Ba, Ra, Sr, Pb, Fe, Th, U and 1. These models have been developed primarily with a view- to providing time-dependent organ retention data which may be used as the basis for calculations of effective dose. However, these new models may also be of value in predicting faecal and urinary excretion rates, particularly if models are adapted for non-standard subjects such as children. In this paper simplified functions for organ retention and instantaneous excretion rates are obtained from the above models, and the latter are compared with excretion functions given in ICRP Publication 54. The potential for using future biokinetic models to predict urinary and faecal excretion rates is discussed. (author)

  20. Relation of urinary calcium and magnesium excretion to blood pressure

    Kesteloot, Hugo; Tzoulaki, Ioanna; Brown, Ian J;

    2011-01-01

    Data indicate an inverse association between dietary calcium and magnesium intakes and blood pressure (BP); however, much less is known about associations between urinary calcium and magnesium excretion and BP in general populations. The authors assessed the relation of BP to 24-hour excretion...... of calcium and magnesium in 2 cross-sectional studies. The International Study of Macro- and Micro-Nutrients and Blood Pressure (INTERMAP) comprised 4,679 persons aged 40-59 years from 17 population samples in China, Japan, the United Kingdom, and the United States, and the International Cooperative Study......) of higher urinary calcium excretion (associations were smaller for diastolic BP) in INTERMAP. Qualitatively similar associations were observed in INTERSALT analyses. Associations between magnesium excretion and BP were small and nonsignificant for most of the models examined. The present data suggest...

  1. Gastrointestinal absorption factor for uranium incorporated in diet

    The gastrointestinal absorption factor (f1) for uranium incorporated in diet was estimated for a group representing the urban Indian population, by studying tha average daily ingestion and urinary excretion of U. The technique of neutron activation was employed to determine the concentration of 238U in daily diet, drinking water and urine samples. The gut absorption factor was found to be 0.016. (author)

  2. Effects of Substrate Complexing Light Rare Earth on Growth, Cd Absorption and Organ Distribution of Sweet Pepper (Capsicum annuum var. annuum)%Effects of Substrate Complexing Light Rare Earth on Growth, Cd Absorption and Organ Distribution of Sweet Pepper (Capsicum annuum var. annuum)

    2012-01-01

    [Objective] The aim was to research effects of substrate complexing light rare earth on growth, Cd absorption and organ distribution of sweet pepper to pro- vide references for development of rhizosphere regulation products in farmland seri- ously polluted. [Method] In the test, effects of substrate cakes (at the same size) and light rare earth (in different doses) on growth, Cd absorption and distribution of green peppers under stress from Cd were explored with a pot experiment. [Result] When 40 mg/kg of rare earth was added into a substrate cake, plant height of pep- per seedlings and the dry weight increased by 21.52% and 11.11%, compared with control group; when Cd was at 5.19 mg/kg (a highly graded pollution), the shoot biomass, olant biomass and dry weight of fruits all enhanced significantly, but root system changed little in the groups where substrate cakes were saved, compared with the group where the substrate cake was washed away. No matter RE was added into substrate cakes or not, root system was significantly inhibited by Cd stress (5.19 mg/kg), but RE at proper dose improved growth of green pepper and had little effect on fruit yielding. In addition, RE had little inhibition on Cd content in roots. RE at 10 mg/kg promoted Cd contents in stems and leaves, but reduced the content in fruits substantially. The regressive equation of Cd content and rare dose in leaves was as follows: y=4E-05x%0.009 6x+0.655 6, FF=0.542 6; the regression equations of Cd content in root, stem and fruit did not make sense. [Conclusion] The experiment lays foundation for further research on heavy metals rhizosphere complexing controlling.

  3. Fecal and urinary excretion of six iodothyronines in the rat

    Fecal and urinary excretion rates of six iodothyronines were assessed in the rat maintained under normal steady state physiological conditions, to gain a more comprehensive understanding of the mechanisms of control of normal thyroid hormone economy and metabolism. Groups of young adult male rats were injected with trace doses of T4, T3, rT3, 3,3'-diiodothyronine (T2), 3',5'-T2, or 3'-monoiodothyronine, each labeled with 125I, and feces and urine were collected separately for up to 10 days. Pooled fecal pellets were homogenized in saline, extracted in ethanol, evaporated under vacuum, and reconstituted in NaOH. Fecal extracts and urine were chromatographed on Sephadex G25 columns under conditions providing quantitative separations of components of interest. A new technique was also developed, based on a model of the in vitro extraction and measurement process, to correct chromatographic results for possible variable recoveries and possible artifactious degradation of radioactively labeled components. No iodothyronines or their conjugates were excreted in urine; all radioactivity was in the form of iodide. In feces, about 30% of the [125I]T3 injected was excreted as T3; and 24% of the [125I]T4 injected was excreted as T4, plus 4% as T3. Together, these results imply that about 24% of endogenous T4 production is excreted as T4 and 76% is irreversibly metabolized; and for T3, about 30% of endogenous T3 production is excreted as T3 and 70% is degraded. For the nonhormonal iodothyronines, about 6% of injected monoiodothyronine, 3% of injected 3',5'-T2, 2% of injected 3,3'-T2, and less than 1% of injected rT3 were excreted in feces as such, indicating that these substances are nearly completely deiodinated in vivo. Very little (1-7%) iodide was excreted as such in feces, which also were devoid of measurable conjugates

  4. Urinary Kallikrein Excretion in Essential and Mineralocorticoid Hypertension

    Holland, O. Bryan; Chud, James M.; Braunstein, Helen

    1980-01-01

    Urinary kallikrein excretion has been reported to be decreased in patients with essential hypertension and elevated in patients with primary aldosteronism as a reflection of mineralocorticoid activity. Low renin essential hypertension (LREH) has been postulated to result from excess production of an unknown mineralocorticoid(s). Urinary kallikrein excretion was compared in outpatients with essential hypertension, mineralocorticoid hypertension (primary aldosteronism and 17α-hydroxylase defici...

  5. Ammonia excretion in mytilid mussels is facilitated by ciliary beating.

    Thomsen, J; Himmerkus, N; Holland, N; Sartoris, F J; Bleich, M; Tresguerres, M

    2016-08-01

    The excretion of nitrogenous waste products in the form of ammonia (NH3) and ammonium (NH4 (+)) is a fundamental process in aquatic organisms. For mytilid bivalves, little is known about the mechanisms and sites of excretion. This study investigated the localization and the mechanisms of ammonia excretion in mytilid mussels. An Rh protein was found to be abundantly expressed in the apical cell membrane of the plicate organ, which was previously described as a solely respiratory organ. The Rh protein was also expressed in the gill, although at significantly lower concentrations, but was not detectable in mussel kidney. Furthermore, NH3/NH4 (+) was not enriched in the urine, suggesting that kidneys are not involved in active NH3/NH4 (+) excretion. Exposure to elevated seawater pH of 8.5 transiently reduced NH3/NH4 (+) excretion rates, but they returned to control values following 24 h acclimation. These mussels had increased abundance of V-type H(+)-ATPase in the apical membranes of plicate organ cells; however, NH3/NH4 (+) excretion rates were not affected by the V-type H(+)-ATPase specific inhibitor concanamycin A (100 nmol l(-1)). In contrast, inhibition of ciliary beating with dopamine and increased seawater viscosity significantly reduced NH3 excretion rates under control pH (8.0). These results suggest that NH3/NH4 (+) excretion in mytilid mussels takes place by passive NH3 diffusion across respiratory epithelia via the Rh protein, facilitated by the water current produced for filter feeding, which prevents accumulation of NH3 in the boundary layer. This mechanism would be energy efficient for sessile organisms, as they already generate water currents for filter feeding. PMID:27489216

  6. Excretion is Faster Than Diagenesis for Nutrient Recycling in Lake Michigan Benthos

    Aguilar, C.; Cuhel, R. L.

    2013-12-01

    nucleic acids and lipid) being excreted. Oddly, the highest quality food resources (low C:N and C:P ratios) lead to the greatest excretion of N and P nutrients in healthy organisms with high metabolic rates. This suggestion is borne out by the spatial distribution of QM excretion rates in transects across seamount-like bathymetric features in south-central Lake Michigan. On the upstream side and plateaus of Northeast and Sheboygan Reefs, where freshly advected bottom water flows across mussel communities, excretion rates in summer 2013 varied around 0.8 and 30 nmol/animal/hr (HPO4= and NH4+ respectively) for robust young adult mussels 15-20mm in length. On the downstream slope, where particles are likely reprocessed several times, nutritional quality and excretion rates were lower, especially for NH4+. Inshore shallow stations have similar rates to upstream nutrient-sufficient populations. Excretion size spectrum regressions combined with population size frequency analyses enable estimation of areal flux. N:P excretion ratios (30-40) are greater than Redfield, and consistent with growing animals nearing their late summer spawning effort. Several years of trophic gradient transects for mussel excretion, and pre- vs. post-QM porewater profiles will support these conclusions.

  7. Excretion of DTPA from human body and the effect of DTPA on the excretion of 241Am in urine

    The excretion of DTPA in urine was studied after intramuscular injection or inhalation as an aerosol. For two administration of DTPA, the excretion fraction of DTPA in urine can be described by sum of two exponent functions. For intramuscular injection, the fast removal part is about 97% of all the activity administered with a half-life of 88 minutes; the slow removal part is about 3% with a half-life of 292 minutes; the excretion rate of DTPA within 24 hours is about 99%. For inhalation of DTPA, the fast removal part is about 81% with a half-life of 92 minutes; the slow removal part is about 19% with a half-life of 624 minutes. The therapeutic effect of DTPA on 241Am is good, the average excretion of 241Am in urine after treatment is 18 times more than that before treatment

  8. Determination of dose coefficients and urinary excretion function for inhalation of carbon-14-labelled benzene

    Based on existing pharmacokinetic models for benzene, the distribution and retention of activity after inhalation of 14C-labelled benzene in humans were studied. Six different benzene concentrations from 0.1 to 10,000 ppm (corresponding to activity concentrations between 9.6 x 106 and 9.6 x 1011 Bq m-3) and five exposure times from 0.1 to 1000 min were considered. The cumulated activities in the different organs and tissues and the urinary excretion rates were observed to depend non-linearly on the activity intake. The fraction of activity removed via urine varies between 52 and 10% of the intake. Nevertheless, for times that are long compared to the exposure duration the urinary excretion rate is determined by the activity clearance from adipose tissue and thus decreases at a constant rate. This decrease is common for all exposure conditions examined and thus allowed determining a mean urinary excretion rate and corresponding dose coefficients for committed equivalent doses as well as for the effective dose. The uncertainty of the dose coefficients is estimated to be about 50% for the exposure range covered. A 14-day interval for the incorporation monitoring by urine activity counting seems to be reasonable. (author)

  9. The Excretion of Thorium X and its Daughter Products after Intravenous Injection in Man

    Thorium X (radium-224, 3.64 d half-life) has been widely used therapeutically in Germany since 1910. The main use today is for the therapy of Spondylarthrosis ankylopoetica (Morbus Bechterew-Struempell- Marie), 250-350 μc are injected intravenously in weekly doses of about 32 μc. The distribution of the gamma-emitting Th X-daughters in the human body was studied by means of a whole-body counter. Faeces and urine were measured without chemical treatment under a big Nal crystal in a mercury shield. The exhaled thoron was measured with a vibrating-reed electrometer arrangement. The measurements show a rapid decrease of the body burden during the first eight days, where about 40% of the administered Th X is excreted. After this period a rather slow excretion modus was observed. These results are compared with those of radium-226 poisoning cases. The decrease of the body burden, the amount of excreted Th X and Th B, and the exhalation of thoron can be described, in good agreement with the experimental values, in the first period by power functions, in the second period by exponential functions. An explanation of the power function model as a superposition of exponential functions is discussed. (author)

  10. Excretion of (3H)prednisolone in clinically normal and experimentally infected bovine udders

    Geleta, J.N.; Shimoda, W.; Mercer, H.D.

    1984-08-01

    The excretion rate of (3H)prednisolone from clinically normal and experimentally infected udders of 10 lactating cows was studied. Each quarter of 6 cows was injected with a single dose of (3H)prednisolone mixed with non-radioactive prednisolone equivalent to 10 mg in 10 ml of peanut oil base. Each of the remaining 4 cows was given 40 mg of nonradioactive prednisolone and (3H)prednisolone in 60% ethanol IV. Control and postadministration samples of blood, milk, and urine were examined for radioactivity. The effects of (3H)prednisolone were evaluated in the same cows, first in clinically normal udders, then 2 weeks later in udders experimentally infected with Streptococcus agalactiae. Absorption and elimination of prednisolone were the same before and after induced infection. Within 3 hours after intramammary injection, 95% of the labeled prednisolone was absorbed systemically, less than 5% of this dose was recovered in milk, and 29% was excreted in urine. After IV injection of (3H)prednisolone, less than 0.2% of the total radioactivity was recovered in milk and less than 46% was excreted in urine. Clinical mastitis induced by S agalactiae was moderate. Circulating blood leukocytes and somatic cells in the milk of normal cows remained essentially unchanged. The leukocyte response to induced infection was rapid in blood and milk. Large numbers of leukocytes were noticed in the milk and a severe leukopenia occurred. Prednisolone treatment did not alter the number of somatic cells in milk or reduce the inflammatory response of experimentally infected cows.

  11. Excretion of [3H]prednisolone in clinically normal and experimentally infected bovine udders

    The excretion rate of [3H]prednisolone from clinically normal and experimentally infected udders of 10 lactating cows was studied. Each quarter of 6 cows was injected with a single dose of [3H]prednisolone mixed with non-radioactive prednisolone equivalent to 10 mg in 10 ml of peanut oil base. Each of the remaining 4 cows was given 40 mg of nonradioactive prednisolone and [3H]prednisolone in 60% ethanol IV. Control and postadministration samples of blood, milk, and urine were examined for radioactivity. The effects of [3H]prednisolone were evaluated in the same cows, first in clinically normal udders, then 2 weeks later in udders experimentally infected with Streptococcus agalactiae. Absorption and elimination of prednisolone were the same before and after induced infection. Within 3 hours after intramammary injection, 95% of the labeled prednisolone was absorbed systemically, less than 5% of this dose was recovered in milk, and 29% was excreted in urine. After IV injection of [3H]prednisolone, less than 0.2% of the total radioactivity was recovered in milk and less than 46% was excreted in urine. Clinical mastitis induced by S agalactiae was moderate. Circulating blood leukocytes and somatic cells in the milk of normal cows remained essentially unchanged. The leukocyte response to induced infection was rapid in blood and milk. Large numbers of leukocytes were noticed in the milk and a severe leukopenia occurred. Prednisolone treatment did not alter the number of somatic cells in milk or reduce the inflammatory response of experimentally infected cows

  12. 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

  13. Changes in parasite transmission stage excretion after pheasant release.

    Villanúa, D; Acevedo, P; Höfle, U; Rodríguez, O; Gortázar, C

    2006-09-01

    The production of parasite transmission stages was investigated in the faeces of 77 farm-bred ring-necked pheasants (Phasianus colchicus). Coccidian oocysts (Eimeria sp.), and nematode eggs (Heterakis sp., and Capillaria-like eggs) were recovered before and after release but all birds were treated prior to release. Treatment with fenbendazole significantly reduced the abundance of transmission-stage excretion for all parasites, and reduced the prevalence in the case of Eimeria sp. and Heterakis sp. Nonetheless, a significant increase in the excretion abundance for all parasites and in the prevalence of Eimeria sp. and Heterakis sp. was found after release. Eggs of Ascaridia sp. were found only after releasing, suggesting infection ocurred in the wild. A negative relationship was found between the pheasant body condition and Heterakis excretion abundance and a higher abundance of Capillaria sp. eggs in female birds. No significant relationship was found between parasite excretion abundance and pheasant survival. Despite this, results suggest that an increase in the excretion of parasite transmission stages follows the release of captive pheasants into the wild. This can in part explain restocking failures, but also means that autochtonous free-living birds may become exposed to new and potentially harmful pathogens. To avoid these risks it is proposed that improved prophylactic measures should be taken. PMID:16923277

  14. Short communication: Individual cow variation in urinary excretion of phosphorus.

    Løvendahl, Peter; Sehested, Jakob

    2016-06-01

    Some dairy cows excrete large amounts of P through their urine; thus, it was speculated that a genetic defect related to their efficiency in uptake of P or recirculation of P could cause such an effect. This speculation was pursued in a cross sectional study on 139 cows (103 Holstein and 36 Jersey) from an experimental herd using repeated sampling of urine (301 samples) to investigate sources of variation in urinary P concentration (Pu). Urine samples were taken on 6 testing sessions spread over 2 mo. Each sample was obtained by mild manual stimulation of the rear udder escutcheon area. The samples were immediately assayed for pH, stored frozen, and assayed for inorganic P and creatinine. Concentrations of P and creatinine in urine, the ratio of Pu to creatinine, and pH were analyzed using a linear mixed model. The model included fixed effects of breed, parity number, and sampling session. Stage of lactation was fitted as Wilmink-type lactation curves. Random effects included additive polygenic ancestry, permanent animal effects, and residual. The distribution of Pu approximated normality except for a single sample with very high Pu and very low pH. This sample came from a cow diagnosed independently with ketosis. For the remaining samples, it was shown that Pu has low to moderate heritability (0.12) and is only moderately repeatable (0.21). Based on a small data set, it is tentatively concluded that individual differences between cows exist in their Pu, and individual differences presumably result from genetic differences. However, it remains unclear if cows with genetically lower or higher Pu will perform better on a low-P diet. PMID:26995137

  15. Preventive obesity agent montmorillonite adsorbs dietary lipids and enhances lipid excretion from the digestive tract

    Xu, Pengfei; Dai, Shu; Wang, Jing; Zhang, Jun; Liu, Jin; Wang, Fang; Zhai, Yonggong

    2016-01-01

    Western diets are typically high in fat and are associated with long-term complications such as obesity and hepatic steatosis. Because of the enjoyable taste of high-fat diets (HFDs), we are interested in determining how to decrease lipid absorption and enhance lipid excretion from the digestive tract after the consumption of eating fatty foods. Montmorillonite was initially characterized as a gastrointestinal mucosal barrier protective agent for the treatment of diarrhoea. Dietary lipid adsorbent- montmorillonite (DLA-M) was isolated and purified from Xinjiang montmorillonite clay via the water extraction method. Here, we show that DLA-M has an unexpected role in preventing obesity, hyperlipidaemia and hepatic steatosis in HFD-fed rats. Interestingly, combined application of polarized light microscopy and lipid staining analyses, showed that DLA-M crystals have dietary lipid-adsorbing ability in vitro and in vivo, which enhances lipid excretion via bowel movements. In summary, our results indicate that DLA-M prevent HFD-induced obesity. This novel dietary lipid-adsorbing agent can help prevent obesity and its comorbidities. PMID:26891902

  16. Water metabolism and modification of tritium excretion in the rat

    1. The intake and excretion of tritium were studied in rats exposed to tritiated water vapor. The metabolism of tritium was also investigated in rats given single administrations of tritiated water and in rats given daily administrations (per os or i.p.). The results were essentially in accord with those reported previously. 2. Amounts of drinking water consumed and urine excreted by rats drinking water with 0.15% saccharin were 1.5 to 2 times higher than in rats drinking tap water. The tritium activity in various tissues of rats drinking water with 0.15% saccharin decreased to about half of that of rats drinking tap water. A similar tendency was observed also in rats drinking beer. The diuretic agent sodium acetazolamide also enhanced the urinary excretion of tritium. (author)

  17. Enantioselective absorption and transformation of a novel chiral neonicotinoid [(14)C]-cycloxaprid in rats.

    Wu, Chengchen; Huang, Lei; Tang, Shenghua; Li, Zhong; Ye, Qingfu

    2016-06-01

    Neonicotinoid pesticides caused hazardous effects on pollinators and aquatic ecosystem. The new developed chiral cis-neonicotinoid cycloxaprid(CYC) is a highly potent substitute for low toxicity to bees and high efficiency on target-insects, but little is known about the metabolic dynamics of racemic CYC and its 2 enantiomers(SR and RS) in animal models. In this study, chiral separation of (14)C-labeled racemic CYC was performed in high-performance liquid chromatography under optimal conditions. For the first time that the stereoselectivity of the chiral neonicotinoid insecticide CYC was exhibited in rats after single dose oral administration using (14)C-labeled isotope trace technique. Enantioselective behaviors of racemic CYC, SR and RS were observed in blood metabolism, tissue distribution and excretion. The major deposition of (14)C were found in liver, lung, kidney and heart. After 24 h, skin and fat showed a strong bioaccumulation effect, and total excreted urine and feces of CYC, SR and RS were 50.4%, 59.7% and 74.5%, respectively. Enantiomer RS had the fastest absorption and elimination rates, and it was least bioaccumulated in rats. The results provide scientific basis and practical techniques for environmental risk assessment of chiral pesticides, especially neonicotinoids. PMID:27038208

  18. Urinary excretion of phthalates and paraben after repeated whole-body topical application in humans

    Janjua, Nadeem Rezaq; Frederiksen, Hanne; Skakkebaek, Niels E;

    2008-01-01

    Diethyl phthalate (DEP), dibutyl phthalate (DBP) and butyl paraben (BP) are man-made chemicals used in personal care products, such as lotions and creams. Exposure to these chemicals causes a variety of adverse reproductive outcomes in animal studies. Humans can be exposed to these chemicals...... were given a whole body topical application of basic cream 2 mg/cm(2) (control week) and then a cream containing 2% (w/w) of DEP, DBP and BP each (treatment week) daily. Twenty-four-hour urine samples were collected. Urinary total, and unconjugated BP, monoethyl phthalate (MEP) and monobutyl phthalate.......1%, respectively. Absorption of DEP, DBP and BP through skin could potentially contribute to adverse health effects. The three chemicals are systemically absorbed, metabolized and excreted in urine following application on the skin in a cream preparation. More DEP than DBP was absorbed, presumably because of a...

  19. Pharmacokinetics, bioavailability, metabolism and excretion of δ-viniferin in rats

    Ping Mao

    2016-05-01

    Full Text Available A highly rapid and sensitive liquid chromatographic–electrospray ionization tandem mass spectrometric (LC–ESI-MS/MS method was developed and validated for the determination of trans-δ-viniferin (Rs-1 in rat plasma, urine and feces. All biological samples were prepared by liquid–liquid extraction and hesperetin was included as an internal standard (IS. Chromatographic separation was achieved on a shim-pack XR-ODS column using a gradient mobile phase. MS/MS detection was performed by negative ion electrospray ionization. The method was sensitive with a lower limit of quantification of 1.42 ng/mL and linear over the range of 1.42–2172 ng/mL in all matrices. The method was applied to study the pharmacokinetics, bioavailability, metabolism, and excretion of Rs-1 in rats following a single oral or intravenous dose. Two metabolites, Rs-1 glucuronide and Rs-1 sulfate, were detected in plasma and in urine after administration of Rs-1. The absolute oral bioavailability of Rs-1 was 2.3%, and the total absorption rose to 31.5% with addition of its glucuronide and sulfate metabolites. Only 0.09% of the gavaged dose, including Rs-1 and metabolites, was excreted in the urine, while 60.3% was found in the feces in unchanged form. The results indicate that both poor absorption and extensive metabolism were the important factors that led to the poor bioavailability of Rs-1, which can provide a basis for further studies on structural modification and dosage form design.

  20. Pharmacokinetics, urinary excretion and dosage regimen of levofloxacin following a single intramuscular administration in cross bred calves

    Dumka, Vinod K.; Srivastava, Anil K.

    2006-01-01

    The pharmacokinetics and urinary excretion following single intramuscular administration of levofloxacin at a dose of 4 mg/kg was investigated in seven male cross bred calves. Appreciable plasma concentration of levofloxacin (0.38 ± 0.06 µg/ml) was detected at 1 min after injection and the peak plasma level of 3.07 ± 0.08 µg/ml was observed at 1 h. The drug level above MIC90 in plasma was detected up to 12 h after administration. Rapid absorption of the drug was also evident by the high value...

  1. Measuring microbial protein supply from purine excretion in Yerli Kara cattle in Turkey

    The urinary excretion of purine derivatives (PD) was measured in four Yerli Kara (Bos indicus) bulls in two experiments, a fasting experiment lasting for 7 days and the other, where animals were given a diet containing 30% wheat straw and 70% compounded feed at four levels of intake (40, 60, 80 and 95% of voluntary feed intake). In the second experiment, which was carried out according to a 4 x 4 Latin Square design, four animals receiving 60 and 95% levels of intake were also given a single injection of 8-14C-uric acid via a jugular catheter. In addition to the above two experiments, the activity of xanthine oxidase and uricase in plasma, liver and intestinal mucosa obtained from Yerli Kara cattle was also determined. In the first experiment, fasting PD excretion averaged 0.691 (± 0.053) mmol/kg W0.75/d. Glomerular filtration rate (GFR), tubular load and net re-absorption of allantoin between pre-fasting and fasting were statistically significant (P 14C-uric acid as total PD was 72.5 and 89.9% for 60 and 95% feeding levels, respectively. The average recovery was 81%. Plasma kinetics measured by 8-14C-uric acid indicated that the total compartment pool size was 214.0 (± 43.8) and 250.3 L (± 29.5) for 60 and 95% feeding levels, respectively. GFR, tubular load and net re-absorption of uric acid and allantoin were not affected by feed intake. The allantoin:PD molar ratios changed between 0.78 to 0.93 for the four levels feed intake. There were significant correlations between PD excretion (mmol/d), and DDMI (kg/d) and DOMI (kg/d) (r = 0.99, P 0.75 DDMI, 19.8 mmol/kg DDMI and 22.7 mmol/kg DOMI. Xanthine oxidase and uricase activities were: 1.34 (± 0.72) and 0.44 (± 0.05), and 0.13 (± 0.03) and 0.08 (± 0.03) unit/g fresh tissue in liver and intestinal mucosa, respectively. In plasma xanthine oxidase activity was 5.0 (± 1.2) unit/L while uricase activity was absent. (author)

  2. Modelling of absorption, distribution and physicochemical properties of AT1 receptor antagonists / Modelovanie absorpcie, distribúcie a fyzikálnochemických vlastnosti antagonistov AT1 receptorov

    Ježko Pavol

    2015-12-01

    Full Text Available The theoretical chemistry methods were used to elucidate absorption, distribution and physicochemical properties of AT1 receptor antagonists and dual angiotensin II and endothelin A receptor antagonist (PS-433540. Computed partition coefficients (ALOGPS method studied for drugs varied between 2.98 and 6.66. Neutral compounds are described as lipophilic drugs. Telmisartan is a drug with the highest lipophilicity. The neutral forms of the studied AT1 receptor antagonists are practically insoluble in water, and their computed solubilities is in interval between 2.04 and 22.65 mg/l (ALOGpS method. The calculated pKa values for tetrazolyle moiety are in the range 3.92-5.00 and for carboxylic moiety 3.12-5.50. Telmisartan (polar surface area = 72.95 A and irbesartan (polar surface area = 87.14 A belong to the AT1 receptor antagonists with increased absorption.

  3. Campylobacter infections in fattening pigs; Excretion pattern and genetic diversity

    Weijtens, M.J.B.M.; Reinders, R.D.; Urlings, H.A.P.; Plas, J. van der

    1999-01-01

    The excretion of campylobacter by eight individually housed fattening pigs was monitored during 15 weeks. Rectal faeces samples were collected six times from these pigs and twice from their mothers (seven sows). Campylobacter was cultured from these samples on Preston medium. In some pigs, samples p

  4. Excretion of depleted uranium by Gulf war veterans

    During the Persian Gulf War, in 1991, approximately 100 US military personnel had potential intakes of depleted uranium (DU), including shrapnel wounds. In 1993, the US government initiated a follow-up study of 33 Gulf War veterans who had been exposed to DU, many of whom contained embedded fragments of DU shrapnel in their bodies. The veterans underwent medical evaluation, whole-body counting, and urinalysis for uranium by kinetic phosphorescence analysis (KPA). Data are available from seven individuals who exceeded the detection limit for whole-body counting and also had elevated urinary uranium. Urinary excretion rates, in μg U g-1 creatinine, were determined in 1997 and 1999. The body contents, in mg DU, were determined in 1997; it is assumed there were no significant decreases in total body content in the interim. For the 1997 data, the mean fractional excretion was (2.4 ± 2.8) x 10-5 g-1 creatinine, and for the 1999 data, the mean was (1.1 ± 0.6) x 10-5 g-1 creatinine. However, these means are not significantly different, nor is there any correlation of excretion rate with body content. Thus, human data available to date do not provide any basis for determining the effects of particle surface area, composition and solubility, and biological processes such as encapsulation, on the excretion rate. (author)

  5. Norovirus Excretion in an Aged-Care Setting▿

    Tu, Elise T.-V.; Rowena A. Bull; Kim, Mi-Jurng; McIver, Christopher J.; Heron, Leon; Rawlinson, William D.; White, Peter A

    2008-01-01

    Norovirus genogroup II excretion during an outbreak of gastroenteritis was investigated in an aged-care facility. Viral shedding peaked in the acute stage of illness and continued for an average of 28.7 days. The viral decay rate was 0.76 per day, which corresponds to a viral half-life of 2.5 days.

  6. Effects of the antituberculous drug ethambutol on zinc absorption, turnover and distribution in rats fed diet marginal and adequate in zinc

    King, A.B.; Schwartz, R.

    1987-04-01

    Ethambutol, (CH/sub 3/CH/sub 2/-CH(CH/sub 2/OH)-NH-CH/sub 2/)/sub 2/ (EMB), is an oral antituberculous agent that is administered therapeutically over extended time periods. It has chelating properties and may affect mineral metabolism. Male weanling Sprague-Dawley rats received 0, 400 or 600 mg EMB per kilogram body weight daily by gavage for 30 d. They were fed a casein-based diet with either adequate (49 ppm) or marginal (11 ppm) zinc. Both adequate-Zn (AZn) and marginal-Zn (MZn) rats receiving EMB showed alopecia and dose-dependent reductions in feed intake, weight gain and feed efficiency. None of these changes was seen in rats fed the MZn diet without EMB. Serum and tissue zinc levels were similar in rats not receiving EMB, regardless of the dietary zinc level. Serum zinc was consistently lower in AZn and MZn rats receiving EMB than in rats without EMB. Apparent zinc absorption, measured by /sup 65/Zn balance, was higher in AZn rats receiving EMB than in AZn rats without EMB. Thus, changes in absorption could not account for lower serum zinc levels in EMB-treated rats. However, /sup 65/Zn turnover was also higher in EMB groups. This suggests that EMB may have increased urinary zinc losses resulting in reduced circulating zinc and a consequent increase in zinc absorption.

  7. Use of faecal excretion function for quick estimation of initial and existing lung burden for occupational exposure control due to 239Pu for S-class of intake

    Two functions namely initial lung deposition and lung retention per unit faecal excretion rate are constructed primarily based on the excretion pattern of four subjects exposed to 239Pu. In the absence of initial clear knowledge about the class of compound inhaled, faecal to urine excretion ratio was used to infer the type of inhaled class. Trends in the urine and faecal data had suggested that the intake was due to mixed class of plutonium compound for each case. With the assumption of 1:1 mixture of plutonium M and S class inhaled compound, faecal excretion rates for only S-class intake were worked out. Uptake inferred based on their urinary data had suggested it to be of similar level within 40% of uncertainty for 5 μm particle size distribution. Data, all the four cases, were pooled for analysis citing the similar level of intake, particle size distribution, nature and pattern of work. The function obtained was tested for S-class lung retention and faecal excretion rate value. These functions are handy tool for estimating initial lung burden and lung retention value for low level of S-class plutonium intake based on subject faecal analysis data. (authors)

  8. Recommendation to Exclude Bile-Duct-Cannulated Rats with Hyperbilirubinemia for Proper Conduct of Biliary Drug Excretion Studies.

    Kato, Koji; Hasegawa, Yoshitaka; Iwata, Katsuya; Ichikawa, Takuya; Yahara, Tohru; Tsuji, Satoshi; Sugiura, Masayuki; Yamaguchi, Jun-Ichi

    2016-08-01

    Hyperbilirubinemia (HB) is sometimes encountered following bile-duct cannulation in rats. It possibly originates from the reduced functioning of multidrug resistance-associated protein 2 (Mrp2) and subsequent adaptive alterations in the expression of Mrp3 and the organic anion transporting polypeptides (Oatps). Our aim was to clarify the importance of excluding bile-duct-cannulated (BDC) rats with HB for proper conduct of drug excretion studies. We detected HB [serum total bilirubin concentration (TBIL) ≥0.20 mg/dl] in 16% of all BDC rats prepared. The serum activities of aspartate aminotransferase, alanine aminotransferase, leucine aminopeptidase, and alkaline phosphatase were within the respective normal ranges in the BDC rats with mild HB (TBIL, 0.20-0.79 mg/dl), indicating the absence of hepatic failure. In the pharmacokinetics of pravastatin, an Oatps/Mrp2 probe drug in the BDC rats, the apparent volume of distribution and the clearance were smaller in the mild HB group as compared with the normal group, suggesting the reduction of apparent hepatic uptake and hepatobiliary elimination. The biliary excretion (percentage of dose) was significantly reduced by 54%, suggesting that the biliary efflux activity via Mrp2 was reduced to a greater extent relative to metabolic activity in hepatocytes. The serum γ-glutamyltransferase (GGT) activity correlated with TBIL and inversely correlated with biliary excretion of pravastatin, a finding which could serve as a clue to uncover the regulatory system involving cooperation between GGT and Mrp2. In conclusion, BDC rats with HB, however mild, should be excluded from drug excretion studies to avoid the risk of underestimation of the biliary excretion of drugs. PMID:27208382

  9. [Distribution and speciation of Pb in Arabidopsis thaliana shoot and rhizosphere soil by in situ synchrotron radiation micro X-ray fluorescence and X-ray absorption near edge structure].

    Shen, Ya-Ting

    2014-03-01

    In order to investigate plant reacting mechanism with heavy metal stress in organ and tissue level, synchrotron radiation micro X-ray fluorescence (micro-SRXRF) was used to determine element distribution characteristics of K, Ca, Mn, Fe, Cu, Zn, Pb in an Arabidopsis thaliana seedling grown in tailing dam soil taken from a lead-zinc mine exploration area. The results showed a regular distribution characters of K, Ca, Fe, Cu and Zn, while Pb appeared not only in root, but also in a leaf bud which was beyond previously understanding that Pb mainly appeared in plant root. Pb competed with Mn in the distribution of the whole seedling. Pb may cause the increase of oxidative stress in root and leaf bud, and restrict Mn absorption and utilization which explained the phenomenon of seedling death in this tailing damp soil. Speciation of Pb in Arabidopsis thaliana and tailing damp rhizosphere soil were also presented after using PbL3 micro X-ray absorption near edge structure (micro-XANES). By comparison of PbL3 XANES peak shape and peak position between standard samples and rhizosphere soil sample, it was demonstrated that the tailing damp soil was mainly formed by amorphous forms like PbO (64.2%), Pb (OH)2 (28.8%) and Pb3O4 (6.3%) rather than mineral or organic Pb speciations. The low plant bioavailability of Pb demonstrated a further research focusing on Pb absorption and speciation conversion is needed, especially the role of dissolve organic matter in soil which may enhance Pb bioavailability. PMID:25208420

  10. Hepcidin and its role in iron absorption

    Robson, K J

    2004-01-01

    Maintaining the correct iron balance is crucial to good health. Disorders of iron homeostasis have a global distribution. As iron is not actively excreted by the body, understanding the role of proteins involved in regulating iron uptake is essential to our understanding of disease involving iron homeostasis. Over the past 10 years, major advances have been made in understanding the genetics of iron metabolism and this has led to identification of a number of new proteins, including hepcidin,...

  11. The influence of different Ca and P ratios in feed on phosphorus turnover and endogenous excretion in growing broiler chicks by means of 32 P isotope

    Endogenous excretion and absorption (turnover) of phosphorus by male broiler chicks (14-29 day old) were quantitatively evaluated in relation to different Ca: P ratios in four groups of experimental diets: (I=1:1, II=1.5:1, III=2:1, IV=2.5:1), adlibitum. The feed mixtures contained 0.6% P in DM. in all groups. Dicalcium phosphate and calcium-Carbonate were added as sources of supplemental P and Ca in experimental diets. At 14 days of age, the chicks were injected with 32 P-Na Po4 intramuscularly in the right leg (6.037 MBq). Isotope dilution technique was used to determine endogenous fecal and renal P excretion. Calcium and phosphorus retentions in the whole-body were calculated according to the comparative slaughter technique. From retention and endogenous excretion, P turnover within the animal was determined. The following results were obtained: Turnover and endogenous excretion of phosphorus amounted (mgP/day/animal): 304, 270, 160 and 158 and 135, 109, 31 and 30 in groups (I, II, III and IV) respectively. The efficiency of utilization of feed phosphorus and calcium retention in the body amounted 36%, 34%, 26% and 24% and 43%, 29%, 21% and 17% in the four groups, respectively. A comparison of relative endogenous excretion of availability of feed phosphorus (group I=100) in the four treatments resulted in: 100:83:24:23 or 100:86:48:45, respectively 56%(I), 60%(II), 81%(III,IV) of P-turnover were retained, respectively. The ratio of relative retention to relative endogenous excretion of absorbed phosphorus was 1.27(I), 1.50(II), 4.26(III and IV), and the ratio of calcium retention to phosphorus retention in the whole body was 1.21(I), 1.25(II), 1.70(III) and 1.71(IV). (author). 47 refs., 14 figs., 15 tabs

  12. Ammonium excretion and oxygen respiration of tropical copepods and euphausiids exposed to oxygen minimum zone conditions

    Kiko, R.; Hauss, H.; Buchholz, F.; Melzner, F.

    2015-10-01

    Calanoid copepods and euphausiids are key components of marine zooplankton communities worldwide. Most euphausiids and several copepod species perform diel vertical migrations (DVMs) that contribute to the export of particulate and dissolved matter to midwater depths. In vast areas of the global ocean, and in particular in the eastern tropical Atlantic and Pacific, the daytime distribution depth of many migrating organisms corresponds to the core of the oxygen minimum zone (OMZ). At depth, the animals experience reduced temperature and oxygen partial pressure (pO2) and an increased carbon dioxide partial pressure (pCO2) compared to their near-surface nighttime habitat. Although it is well known that low oxygen levels can inhibit respiratory activity, the respiration response of tropical copepods and euphausiids to relevant pCO2, pO2 and temperature conditions remains poorly parameterized. Further, the regulation of ammonium excretion at OMZ conditions is generally not well understood. It was recently estimated that DVM-mediated ammonium supply considerably fuels bacterial anaerobic ammonium oxidation - a major loss process for fixed nitrogen in the ocean. These estimates were based on the implicit assumption that hypoxia or anoxia in combination with hypercapnia (elevated pCO2) does not result in a downregulation of ammonium excretion. Here we show that exposure to OMZ conditions can result in strong depression of respiration and ammonium excretion in calanoid copepods and euphausiids from the Eastern Tropical North Atlantic and the Eastern Tropical South Pacific. These physiological responses need to be taken into account when estimating DVM-mediated fluxes of carbon and nitrogen into OMZs.

  13. The effect of surgery on the renal excretion of beta 2-microglobulin.

    Walenkamp, G H; Vree, T B; Guelen, P J; Jongman-Nix, B

    1983-03-28

    Surgical trauma causes an increase in the renal excretion rate of beta 2-microglobulin whilst creatinine excretion is not influenced. The increase in the renal excretion rate of beta 2-microglobulin is probably the result of an increased release of beta 2-microglobulin by the cells which exceeds a maximum in the active tubular reabsorption of the compound by the proximal tubule cell. The renal excretion of beta 2-microglobulin is proportional to the relative clinical trauma score. PMID:6189646

  14. Distribution of Cold ($\\lesssim 300$K) Atomic Gas in Galaxies: Results from the GBT HI Absorption Survey Probing the Inner Halos ($\\rho<20$kpc) of Low-z Galaxies

    Borthakur, Sanchayeeta

    2016-01-01

    We present the Green Bank Telescope absorption survey of cold atomic hydrogen ($\\lesssim 300$K) in the inner halo of low-redshift galaxies. The survey aims to characterize the cold gas distribution and to address where condensation - the process where ionized gas accreted by galaxies condenses into cold gas within the disks of galaxies - occurs. Our sample consists of 16 galaxy-quasar pairs with impact parameters of $\\le$ 20kpc. We detected an HI absorber associated with J0958+3222 (NGC 3067) and HI emission from six galaxies. We also found two \\ion{Ca}{2} absorption system in the archival SDSS data associated with galaxies J0958+3222 and J1228+3706, although the sample was not selected based on the presence of metals in absorption. Our detection rate of HI absorbers with optical depths of $\\ge 0.06$ is $\\sim$7\\%. We also find that cold HI phase ($\\lesssim$300K) is 44($\\pm$18)\\% of the total atomic gas in the sightline probing J0958+3222. We find no correlation between the peak optical depth and impact parame...

  15. Effect of colchicine on rat small intestinal absorptive cells. II. Distribution of label after incorporation of [3H]fucose into plasma membrane glycoproteins

    By means of radioautography the influence was tested of various periods (5, 15, 30, 40 min, 2 hr) of pretreatment with colchicine, administered intraperitoneally to rats at a dosage of 0.5 mg/100 g of body weight, on the intracellular pathway of [3H]fucose in absorptive cells of the small intestine. Administration of colchicine for 30 min and longer time intervals causes delay in the insertion of [3H]fucose into the oligosaccharide chains of glycoconjugates in the Golgi apparatus, and results in redistribution of the label apparent over the different portions of the plasma membrane. In controls, at 2 and 4 hr after administration of [3H]fucose the apical plasma membrane is strongly labeled. Colchicine causes equalization of the reaction of apical and basolateral regions of the plasma membrane: the number of silver grains attributable to the apical plasma membrane is reduced; following treatment with colchicine, apical portions of the plasma membrane comprise 31.6 +/- 1.8% of the silver grains, 38.6 +/- 3.8% are attributable to basolateral membrane regions. The colchicine-induced equalization of the density of label of apical and basolateral regions of the plasma membrane, in addition to the occurrence of basolateral microvillus borders, suggests microtubules to be important in the maintenance of the polar organization of small intestinal absorptive cells

  16. Absorption Of Dietary Lipid Components

    Abdulkadir Hurşit

    2015-01-01

    Although the digestion and absorption of lipids that are necessary for the survival of living organisms are well known in general terms, nevertheless how different lipids to be digested, how it is distributed into the bloodstream, and how to be used by the cells, are unknown issues by most non specialist people. In recent years, knowledge of lipid digestion and absorption has expanded considerably. More insight has been gained in the mechanism of action of H + pump as a transport system in fa...

  17. Urinary albumin excretion in a population based sample of 1011 middle aged non-diabetic subjects. The Copenhagen City Heart Study Group

    Jensen, J S; Feldt-Rasmussen, B; Borch-Johnsen, K;

    1993-01-01

    Increased urinary albumin excretion rate (UAER) especially in the range of 20-200 micrograms min-1, termed microalbuminuria, has been proposed as a risk marker and predictor for cardiovascular disease in non-diabetic subjects. Thus it would be of importance to describe the distribution of UAER in...

  18. Human urinary excretion of non-persistent environmental chemicals

    Frederiksen, Hanne; Jensen, Tina Kold; Jørgensen, Niels;

    2014-01-01

    ), triclosan (TCS), and parabens because of their anti-androgenic and/or estrogenic effects. Phthalates are plasticizers used in numerous industrial products. Bisphenol A is the main component of polycarbonate plastics and epoxy resins. Parabens and TCS are antimicrobial preservatives and other phenols...... limited. In Denmark, we have no survey programs for non-persistent environmental chemicals, unlike some countries such as the USA (NHANES) and Germany (GerES). However, we have analyzed the excretion of seven parabens, nine phenols, and the metabolites of eight different phthalates in urine samples......, and to at least two of the parabens. The exposure to other non-persistent chemicals was also widespread. Our data indicate decreasing excretion of two common phthalates (di-n-butyl phthalate and di-(2-ethylhexyl) phthalate) over time....

  19. Uric acid excretion predicts increased aggression in urban adolescents.

    Mrug, Sylvie; Mrug, Michal

    2016-09-01

    Elevated levels of uric acid have been linked with impulsive and disinhibited behavior in clinical and community populations of adults, but no studies have examined uric acid in relation to adolescent aggression. This study examined the prospective role of uric acid in aggressive behavior among urban, low income adolescents, and whether this relationship varies by gender. A total of 84 adolescents (M age 13.36years; 50% male; 95% African American) self-reported on their physical aggression at baseline and 1.5years later. At baseline, the youth also completed a 12-h (overnight) urine collection at home which was used to measure uric acid excretion. After adjusting for baseline aggression and age, greater uric acid excretion predicted more frequent aggressive behavior at follow up, with no significant gender differences. The results suggest that lowering uric acid levels may help reduce youth aggression. PMID:27180134

  20. Ammonia emissions from cattle urine and dung excreted on pasture

    Laubach, J; Taghizadeh-Toosi, Arezoo; Gibbs, S J; Sherlock, R R; Kelliher, F M; Grover, S P P

    2013-01-01

    Twelve cattle were kept for three days in a circular area of 16 m radius on short pasture and fed with freshly-cut pasture. Ammonia (NH3) emissions from the urine and dung excreted by the cattle were measured with a micrometeorological mass-balance method, during the cattle presence and for 10...... subsequent days. Daily-integrated emission rates peaked on Day 3 of the experiment (last day of cattle presence) and declined steadily for five days thereafter. Urine patches were the dominant sources for these emissions. On Day 9, a secondary emissions peak occurred, with dung pats likely to be the main...... sources. This interpretation is based on simultaneous observations of the pH evolution in urine patches and dung pats created next to the circular plot. Feed and dung samples were analysed to estimate the amounts of nitrogen (N) ingested and excreted. Total N volatilised as NH3 was 19.8 (± 0.9)% of N...

  1. Absorption, Pharmacokinetics, and Safety of Triclosan after Dermal Administration▿

    Queckenberg, Christian; Meins, Jürgen; Wachall, Bertil; Doroshyenko, Oxana; Tomalik-Scharte, Dorota; Bastian, Bärbel; Abdel-Tawab, Mona; Fuhr, Uwe, 1960-

    2009-01-01

    We evaluated the pharmacokinetics and safety of the antimicrobial agent triclosan after dermal application of a 2% triclosan-containing cream to six volunteers. Percutaneous absorption calculated from urinary excretion was 5.9% ± 2.1% of the dose (mean ± standard deviation). The amount absorbed suggests that daily application of a standard adult dose would result in a systemic exposure 890 times lower than the relevant no-observed-adverse-effect level. Triclosan can be considered safe for use...

  2. Amorphous Silica Based Nanomedicine with Safe Carrier Excretion and Enhanced Drug Efficacy

    Zhang, Silu

    With recent development of nanoscience and nanotechnology, a great amount of efforts have been devoted to nanomedicine development. Among various nanomaterials, silica nanoparticle (NP) is generally accepted as non-toxic, and can provide a versatile platform for drug loading. In addition, the surface of the silica NP is hydrophilic, being favorable for cellular uptake. Therefore, it is considered as one of the most promising candidates to serve as carriers for drugs. The present thesis mainly focuses on the design of silica based nanocarrier-drug systems, aiming at achieving safe nanocarrier excretion from the biological system and enhanced drug efficacy, which two are considered as most important issues in nanomedicine development. To address the safe carrier excretion issue, we have developed a special type of selfdecomposable SiO2-drug composite NPs. By creating a radial concentration gradient of drug in the NP, the drug release occurred simultaneously with the silica carrier decomposition. Such unique characteristic was different from the conventional dense SiO2-drug NP, in which drug was uniformly distributed and can hardly escape the carrier. We found that the controllable release of the drug was primarily determined by diffusion, which was caused by the radial drug concentration gradient in the NP. Escape of the drug molecules then triggered the silica carrier decomposition, which started from the center of the NP and eventually led to its complete fragmentation. The small size of the final carrier fragments enabled their easy excretion via renal systems. Apart from the feature of safe carrier excretion, we also found the controlled release of drugs contribute significantly to the drug efficacy enhancement. By loading an anticancer drug doxorubicin (Dox) to the decomposable SiO 2-methylene blue (MB) NPs, we achieved a self-decomposable SiO 2(MB)-Dox nanomedicine. The gradual escape of drug molecules from NPs and their enabled cytosolic release by optical

  3. RENAL CLEARANCE AND URINARY EXCRETION OF CIPROFLOXACIN IN GOATS

    Z. IQBAL, I. JAVED, B. ASLAM, F. MUHAMMAD AND I. U. JAN

    2007-01-01

    The renal clearance and urinary excretion of ciprofloxacin were investigated in eight healthy female goats. In each animal, ciprofloxacin was administered intramuscularly at the rate of 5 mg/kg body weight. Following drug administration, blood and urine samples were collected at different time intervals and analyzed for ciprofloxacin and creatinine. High performance liquid chromatography (HPLC) was used to determine the drug concentration in the plasma and urine. The value of diuresis after s...

  4. Glucocorticoids increase salt appetite by promoting water and sodium excretion

    Thunhorst, Robert L.; Beltz, Terry G.; Johnson, Alan Kim

    2007-01-01

    Glucocorticoids [e.g., corticosterone and dexamethasone (Dex)], when administered systemically, greatly increase water drinking elicited by angiotensin and sodium ingestion in response to mineralocorticoids [e.g., aldosterone and deoxycorticosterone acetate (DOCA)], possibly by acting in the brain. In addition, glucocorticoids exert powerful renal actions that could influence water and sodium ingestion by promoting their excretion. To test this, we determined water and sodium intakes, excreti...

  5. Excretion of radium in relation to dietary intake

    Comprehensive measurements of the Ra226 contents of more than 200 common foods and 100 of the principal supplies of drinking water in Great Britain have been used to compare the mean intakes of radium per person from these sources, in a number of occupational groups as well as among the populations of various region; of the country. In spite of the wide range of activities present in foods, the mean intakes show little variation among the groups, the values lying between 2 and 3 pc per person per day. The drinking waters in Britain have radium contents differing by factors of up to 250 to 1, but in the majority of cases the absolute levels are so low relative to those present in the staple foods that the mean intakes from water represent only 5 to 6% of the mean total amounts of radium ingested by each individual. Only in one exceptional area of the country, representing less than 1% of the total population, is it possible for the daily intakes from water to exceed those from food. Measurements of faecal excretion resulting from the normal dietary intake have shown that in the case of young adults, the average level of Ra226 excreted in this way is 2 to 2.5 pc/d. This figure agrees with the estimates of the mean daily intakes. Human metabolic studies have shown that the large majority of each day's dietary intake of radium is excreted within 24 to 48 h, but attempts to assess the fractional retention in adults have given variable results. Measurements of the daily intakes and faecal excretions of a young child, over a period of 33 d, indicate that the retention of radium during periods of active bone growth may be as high as 10% or even more. (author)

  6. Blood pressure, sodium intake, insulin resistance, and urinary nitrate excretion.

    Facchini, F S; DoNascimento, C; Reaven, G M; Yip, J W; Ni, X P; Humphreys, M H

    1999-04-01

    The objective of this study was to investigate the relationships among various humoral factors thought to be involved in the regulation of blood pressure during high NaCl intake. Nineteen healthy subjects underwent sequential 5-day periods ingesting a low-sodium (25 mmol/d) or high-sodium (200 mmol/d) diet. Insulin resistance was assessed by the steady-state plasma glucose concentration at the end of a 3-hour insulin suppression test. Insulin resistance correlated inversely with natriuresis (P=0.04) and directly with increase in weight (P=0.03). The increase in mean arterial pressure associated with the high-sodium diet correlated directly with the gain in weight (P<0.05) and inversely with the increase in urinary nitrate excretion (P<0.0001). In a multiple regression model, more than 2/3 of the variance in mean arterial pressure was accounted for by the gain in weight and change in urinary nitrate excretion. The steady-state plasma glucose concentrations obtained with the 2 diets were similar, indicating that insulin resistance was unaffected by sodium intake. During high sodium intake, plasma renin activity and aldosterone decreased and plasma atrial natriuretic peptide increased; these changes did not correlate with the change in mean arterial pressure, insulin resistance, or change in urinary nitrate excretion. To the extent that urinary nitrate excretion reflects activity of the endogenous nitric oxide system, these results suggest that the salt sensitivity of mean arterial pressure may be related to blunted generation of endogenous nitric oxide. The results also demonstrate that insulin-resistant individuals have an impaired natriuretic response to high sodium intake. PMID:10205239

  7. Ammonia emissions from cattle urine and dung excreted on pasture

    J. Laubach

    2013-01-01

    Full Text Available Twelve cattle were kept for three days in a circular area of 16 m radius on short pasture and fed with freshly-cut pasture. Ammonia (NH3 emissions from the urine and dung excreted by the cattle were measured with a micrometeorological mass-balance method, during the cattle presence and for 10 subsequent days. Daily-integrated emission rates peaked on Day 3 of the experiment (last day of cattle presence and declined steadily for five days thereafter. Urine patches were the dominant sources for these emissions. On Day 9, a secondary emissions peak occurred, with dung pats likely to be the main sources. This interpretation is based on simultaneous observations of the pH evolution in urine patches and dung pats created next to the circular plot. Feed and dung samples were analysed to estimate the amounts of nitrogen (N ingested and excreted. Total N volatilised as NH3 was 19.8 (± 0.9% of N intake and 22.4 (± 1.3% of N excreted. The bimodal shape of the emissions time series allowed to infer separate estimates for volatilisation from urine and dung, respectively, with the result that urine accounted for 88.6 (± 2.6% of the total NH3 emissions. The emissions from urine represented 25.5 (± 2.0% of the excreted urine-N, while the emissions from dung amounted to 11.6 (± 2.7% of the deposited dung-N. Emissions from dung may have continued after Day 13 but were not resolved by the measurement technique. A simple resistance model shows that the magnitude of the emissions from dung is controlled by the resistance of the dung crust.

  8. Urinary excretion of platinum from platinum industry workers

    Schierl, R.; Fries, H. G.; van de Weyer, C.; Fruhmann, G

    1998-01-01

    OBJECTIVES: Assessment of level of exposure to platinum and platinum concentration in urine from platinum industry workers to evaluate internal exposures and excretion kinetics. METHODS: Platinum concentrations in urine samples from 34 workers were measured by adsorptive voltammetry after UV-photolysis. Morning and evening samples were taken two to six times during six months. Individual exposures were assessed by personal air sampling. Also, two male volunteers were exposed to platinum...

  9. Accumulation and excretion of radionuclides by alga Chara tomentosa

    It has been found in the course of the study of accumulation and excretion of radionuclides by alga chara tomentosa that 55Fe, 60Co, 91Y are accumulated by living and dead components of alga chara tomentosa to a far greater extent and are stronger retained than 90Sr, 137Cs, 144Ce. The main part of the absorbed quantities of all investigated nuclides (80-92%) is fixed on the surface of the plant in the ''cortex'' layer

  10. Ammonia Production, Excretion, Toxicity, and Defense in Fish: A Review

    Ip, Yuen K.; Chew, Shit F.

    2010-01-01

    Many fishes are ammonotelic but some species can detoxify ammonia to glutamine or urea. Certain fish species can accumulate high levels of ammonia in the brain or defense against ammonia toxicity by enhancing the effectiveness of ammonia excretion through active NH 4 + transport, manipulation of ambient pH, or reduction in ammonia permeability through the branchial and cutaneous epithelia. Recent reports on ammonia toxicity in mammalian brain reveal the importance of permeation of ammonia thr...

  11. Study about excretion of 210 Po in urine

    The urine of mines's workers are analysed to detect the presence of 210 Po. The results was compared with the workers and with a control population. Cigarettes samples was analysed two and confirmed the 210 presence. The control population individuals were divided in smokers and non smokers and them urine was investigated the influence of the smoke in the 210 Po excretion. (L.M.J.)

  12. Excreted Cytoplasmic Proteins Contribute to Pathogenicity in Staphylococcus aureus.

    Ebner, Patrick; Rinker, Janina; Nguyen, Minh Thu; Popella, Peter; Nega, Mulugeta; Luqman, Arif; Schittek, Birgit; Di Marco, Moreno; Stevanovic, Stefan; Götz, Friedrich

    2016-06-01

    Excretion of cytoplasmic proteins in pro- and eukaryotes, also referred to as "nonclassical protein export," is a well-known phenomenon. However, comparatively little is known about the role of the excreted proteins in relation to pathogenicity. Here, the impact of two excreted glycolytic enzymes, aldolase (FbaA) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH), on pathogenicity was investigated in Staphylococcus aureus Both enzymes bound to certain host matrix proteins and enhanced adherence of the bacterial cells to host cells but caused a decrease in host cell invasion. FbaA and GAPDH also bound to the cell surfaces of staphylococcal cells by interaction with the major autolysin, Atl, that is involved in host cell internalization. Surprisingly, FbaA showed high cytotoxicity to both MonoMac 6 (MM6) and HaCaT cells, while GAPDH was cytotoxic only for MM6 cells. Finally, the contribution of external FbaA and GAPDH to S. aureus pathogenicity was confirmed in an insect infection model. PMID:27001537

  13. Evaluation of aldosterone excretion in very low birth weight infants.

    Abdel Mohsen, Abdel Hakeem; Taha, Gamal; Kamel, Bothina A; Maksood, Mohamed Abdel

    2016-01-01

    Data about aldosterone production and excretion in the neonatal period are still few and controversial. Our objectives are to assess urinary aldosterone excretion (UAE) in very low birth weight (VLBW) infants and to identify clinical and biochemical variables that may influence this excretion. Thirty VLBW infants (14 males and 16 females), their gestational age value was 0.176 ± 0.05 μg/24 h and the mean absolute UAE was 1906 ± 271 pg/mL. There was a statistically significant positive correlation between UAE and gestational age and birth weight; also, infants with respiratory distress syndrome had higher urinary aldosterone levels than infants without respiratory distress. Only plasma sodium was a significant independent factor that negatively influenced UAE on linear regression analysis. The renin-angiotensin-aldosterone system of VLBW infants seems to be able, even immediately after birth, to respond to variations of plasma sodium concentrations; measurement of UAE constitutes an interesting method to determine aldosterone production in VLBW infants. PMID:27424689

  14. Sulfate and taurine excretion in rats after L-cysteine administration.

    Yoshida,Shigeko; Akagi,Rriko; Ubuka,Toshihiko

    1989-01-01

    Excretion of sulfate and taurine, two major metabolites of sulfur, was examined in rats to study the nutritional status of sulfur metabolism in the mammals. Rats maintained on a conventional laboratory diet excreted 1.83 +/- 0.14 mmol of free sulfate and 229.0 +/- 75.3 mumol of taurine/kg of body weight per day. When the diet was changed to a synthetic 25% casein diet, the taurine excretion decreased to 15% of the previous daily excretion, but sulfate excretion decreased only slightly. These ...

  15. The impact of gender and puberty on reference values for urinary growth hormone excretion

    Main, K M; Jarden, M; Angelo, L; Dinesen, Birthe Irene; Hertel, Niels; Juul, A; Müller, J; Skakkebaek, N E

    1994-01-01

    . Short collection periods (<6 h) were related to low values for U-GH excretion (nanograms per night; P <0.02). This time effect disappeared if U-GH excretion was expressed as picograms per h. If U-GH was related to creatinine output, there was a decrease in U-GH excretion during prepuberty, a blunting of...... creatinine. We conclude that the assay was suitable for measurement of U-GH excretion in virtually all healthy volunteers. Sex and pubertal stage as well as urinary volume and clock times for collection periods should be registeredwhen establishing a reference range for U-GH excretion and applying it for...

  16. Population specific absorption studies for some diet incorporated trace elements : comparison with ICRP data

    Daily intake and excretion can provide an important information regarding the absorption through the gastro-intestinal tract (f1 factor) of trace elements incorporated in diet. The absorption may depend upon the kind of diet consumed, the content of the fibre, protein etc and it could be quite different for two populations groups with entirely different food habits. ICRP has provided data on the intake and excretion of 63 trace elements by Caucasian population representing North American and European adults. This paper reports intake and excretion of twelve elements Na, K, Ca, Mg, Cu, Mn, Rb, Fe, Zn, Sr, Li and Cr for an urban adult Indian population group and compares with corresponding data on ICRP reference man. (author)

  17. Electronic structure, bonding, charge distribution, and x-ray absorption spectra of the (001) surfaces of fluorapatite and hydroxyapatite from first principles

    Rulis, Paul; Yao, Hongzhi; Ouyang, Lizhi; Ching, W. Y.

    2007-12-01

    Fluorapatite (FAP) and hydroxyapatite (HAP) are two very important bioceramic crystals. The (001) surfaces of FAP and HAP crystals are studied by ab initio density functional calculations using a supercell slab geometry. It is shown that in both crystals, the O-terminated (001) surface is more stable with calculated surface energies of 0.865 and 0.871J/m2 for FAP and HAP, respectively. In FAP, the two surfaces are symmetric. In HAP, the orientation of the OH group along the c axis reduces the symmetry such that the top and bottom surfaces are no longer symmetric. It is revealed that the atoms near the surface and subsurface are significantly relaxed especially in the case of HAP. The largest relaxations occurred via the lateral movements of the O ions at the subsurface level. The electronic structures of the surface models in the form of layer-by-layer resolved partial density of states for all the atoms show systematic variation from the surface region toward the bulk region. The calculated Mulliken effective charge on each type of atom and the bond order values between cations (Ca, P) and anions (O, F) show different charge transfers and bond strength variations from the bulk crystal values. Electron charge density calculations show that the surfaces of both FAP and HAP crystals are mostly positively charged due to the presence of Ca ions at the surface. The positively charged surfaces have implications for the absorption on apatite surfaces of water and other organic molecules in an aqueous environment which are an important part of its bioactivity. The x-ray absorption near-edge structure (XANES) spectra ( Ca-K , O-K , F-K , P-K , and P-L3 edges) of both the surface models and the bulk crystals are calculated and compared. The calculations use a supercell approach which takes into account the electron-core-hole interaction. It is shown that the site-specific XANES spectra show significant differences between atoms near the surface and in the bulk and are very

  18. 15N tracer methodology for absorption studies in nutrition research

    Proceeding from 15N analyses, 15N tracer methods, and a model of protein metabolism it is shown that the nitrogen balance is a useful concept for expressing the relationship between the overall nitrogen intake of the body and the nitrogen excretion. After admistering low doses of 15N-labelled substances like protein and amino acids, the kinetics of digestion and absorption can be followed by measuring the 15N abundance in serum and urine of patients. A significant delay in the nitrogen absorption indicates gastrointestinal disorders

  19. Diurnal Variation and Spatial Distribution Effects on Sulfur Speciation in Aerosol Samples as Assessed by X-Ray Absorption Near-Edge Structure (XANES)

    Siwatt Pongpiachan; Kanjana Thumanu; Warangkana Na Pattalung; Phoosak Hirunyatrakul; Itthipon Kittikoon; Kin Fai Ho; Junji Cao

    2012-01-01

    This paper focuses on providing new results relating to the impacts of Diurnal variation, Vertical distribution, and Emission source on sulfur K-edge XANES spectrum of aerosol samples. All aerosol samples used in the diurnal variation experiment were preserved using anoxic preservation stainless cylinders (APSCs) and pressure-controlled glove boxes (PCGBs), which were specially designed to prevent oxidation of the sulfur states in PM10. Further investigation of sulfur K-edge XANES spectra rev...

  20. Intestinal Npt2b Plays a Major Role in Phosphate Absorption and Homeostasis

    Sabbagh, Yves; O'Brien, Stephen P.; Song, Wenping; Boulanger, Joseph H; Stockmann, Adam; Arbeeny, Cynthia; Schiavi, Susan C.

    2009-01-01

    Intestinal phosphate absorption occurs through both a paracellular mechanism involving tight junctions and an active transcellular mechanism involving the type II sodium-dependent phosphate cotransporter NPT2b (SLC34a2). To define the contribution of NPT2b to total intestinal phosphate absorption, we generated an inducible conditional knockout mouse, Npt2b−/− (Npt2bfl/fl:Cre+/−). Npt2b−/− animals had increased fecal phosphate excretion and hypophosphaturia, but serum phosphate remained unchan...

  1. A study of the distribution of aluminium in human placental tissues based on alkaline solubilization with determination by electrothermal atomic absorption spectrometry.

    Kruger, Pamela C; Schell, Lawrence M; Stark, Alice D; Parsons, Patrick J

    2010-09-01

    Aluminium (Al) is a nonessential element known to induce neurotoxic effects, such as dialysis dementia, in patients on hemodialysis, with compromised kidney function. The role of Al in the progression of some neurodegenerative diseases, such as Alzheimer's disease (AD), is controversial, and remains unclear. The effects of Al on other vulnerable populations, such as fetuses and infants, have been infrequently studied. In the present study, Al has been measured in human placenta samples, comprising ∼160 each of placenta bodies, placenta membranes, and umbilical cords, using electrothermal atomic absorption spectrometry (ETAAS) after atmospheric pressure digestion with tetramethylammonium hydroxide (TMAH) and ethylenediaminetetraacidic acid (EDTA). The sensitivity, or characteristic mass (m(0)), for Al at the 309.3-nm line was found to be 30 ± 4 pg. The instrumental detection limit (IDL) (3s) for Al in solution was calculated as 0.72 μg L(-1) while the method detection limit (MDL) (3s) was 0.25 μg g(-1). Accuracy was assessed through analysis of quality control (QC) materials, including certified reference materials (CRMs), in-house reference materials (RMs), and spike recovery experiments, of varying matrices. Placental tissue analyses revealed geometric mean concentrations of approximately 0.5 μg g(-1) Al in placenta bodies (n = 165) and membranes (n = 155), while Al concentrations in umbilical cords (n = 154) were about 0.3 μg g(-1). Al was detected in 95% of placenta bodies, and 81% of placenta membranes, but only in 46% of umbilical cords. PMID:21072353

  2. Natural intake and excretion of thorium and uranium

    The natural content of the isotopes 238Th, 230Th and 232Th in faeces as well as 234U, 235U and 238U in drinking-water has been investigated by means of α-spectroscopy. The averaged total activity of thorium in faeces has been found to be 56,6 mBq per daily excretion, the activity of uranium in drinking water is reported to be 11.3 mBq/l. The results are in comparison with the existing data from Germany, but different to international suppositions as in UNSCEAR or ICRP 23. (orig.)

  3. Radiation dosimetry from breast milk excretion of radioiodine and pertechnetate

    Measurements were made of the activity in samples of breast milk obtained from a patient with postpartum thyroiditis following administration of [123I]sodium iodide and subsequently [99mTc]pertechnetate 24 hr later. Both 123I and 99mTc were found to be excreted exponentially with an effective half-life of 5.8 hr and 2.8 hr, respectively. Less than 10% of the activity was incorporated into breast-milk protein. After administration of [123I]sodium iodide breast feeding should be discontinued for 24-36 hr to reduce the absorbed dose to the child's thyroid

  4. Sup(123)I excretion in breast milk - additional data

    A woman with a suspected sublingual thyroid was referred for thyroid imaging with 123I-sodium iodide. On attending it was ascertained that she was currently breastfeeding her 3-month-old baby. Reference to the available literature showed little information regarding the excretion of 123I-sodium iodide in human breast milk apart from one single case. It was felt therefore that this would be an ideal opportunity to collect some useful data. Originally the presence of impurities in the radiopharmaceutical administered had been discounted as being of little significance. However, after consideration, a review of the contribution of any impurity was undertaken. (author)

  5. Pharmacokinetics: metabolism and renal excretion of quinolones in man.

    Vree, T B; Wijnands, W J; Guelen, P J; Baars, A M; Hekster, Y A

    1986-02-21

    The quinolones are relatively poorly absorbed from the gastrointestinal tract. The elimination proceeds mainly by renal excretion. The half-life of elimination depends on the molecular structure and varies between 2 and 10 h. Impaired kidney function is expected to increase the half-life of elimination, though this effect is not always observed. Since the 4-oxo-metabolites show a higher renal clearance than the parent drug, renal impairment will result in a cumulation of the metabolites in the body. PMID:3960691

  6. Sup(123)I excretion in breast milk - additional data

    Lawes, S.C. (Queen' s Medical Centre, Nottingham (United Kingdom))

    1992-07-01

    A woman with a suspected sublingual thyroid was referred for thyroid imaging with {sup 123}I-sodium iodide. On attending it was ascertained that she was currently breastfeeding her 3-month-old baby. Reference to the available literature showed little information regarding the excretion of {sup 123}I-sodium iodide in human breast milk apart from one single case. It was felt therefore that this would be an ideal opportunity to collect some useful data. Originally the presence of impurities in the radiopharmaceutical administered had been discounted as being of little significance. However, after consideration, a review of the contribution of any impurity was undertaken. (author).

  7. Estimation of uptake from censored urine excretion data

    The estimation of radionuclide uptake often involves consideration of measurements of urine excretion which may include some values reported as below the limit of detection (LOD). Data sets which contain below LOD data as well as positive results are known as censored data sets. A simple method which uses the information contained in censored data to estimate uptake is described. A Monte Carlo technique has been used to investigate the accuracy and the efficiency of the method using simulated data sets with increasing numbers of LOD data points. (author)

  8. Absorption boundary conditions for geomertical acoustics

    Jeong, Cheol-Ho

    2012-01-01

    Defining accurate acoustical boundary conditions is of crucial importance for room acoustic simulations. In predicting sound fields using phased geometrical acoustics methods, the absorption coefficients or surface impedances of the boundary surfaces can be used, but no guideline has been developed...... solutions. Two rectangular rooms with uniform and non-uniform absorption distributions are tested. It is concluded that the impedance and random incidence absorption boundary conditions produce reasonable results with some exceptions at low frequencies for acoustically soft materials....

  9. RENAL CLEARANCE AND URINARY EXCRETION OF CIPROFLOXACIN IN GOATS

    Z. IQBAL, I. JAVED, B. ASLAM, F. MUHAMMAD AND I. U. JAN

    2007-10-01

    Full Text Available The renal clearance and urinary excretion of ciprofloxacin were investigated in eight healthy female goats. In each animal, ciprofloxacin was administered intramuscularly at the rate of 5 mg/kg body weight. Following drug administration, blood and urine samples were collected at different time intervals and analyzed for ciprofloxacin and creatinine. High performance liquid chromatography (HPLC was used to determine the drug concentration in the plasma and urine. The value of diuresis after single administration of ciprofloxacin was 0.073 ± 0.014 ml/min/kg. Mean (± SE values for renal clearance of creatinine and ciprofloxacin were 1.870 ± 0.385 and 0.982 ± 0.166 ml/min/kg, respectively. The ratio between the renal clearance of ciprofloxacin and that of creatinine remained less than one, which was indicative of back diffusion. The mean (± SE value for the cumulative percent of ciprofloxacin dose excreted at 10 hours following its intramuscular administration was 13.03 ± 2.07. Based on these results, it was evident that besides glomerular filtration, renal handling of drug involved back diffusion also. It was concluded that in local goats glomerular filtration rate (GFR was lower than that reported for their foreign counterparts.

  10. Excretion technique of radioactive materials in vivo by complex formation

    To establish an excretion technique of RI metals (63Ni, 109Cd and 210Pb) in vivo, many kinds of complexing agents were developed. The performance evaluation of these agents was carried out by mouse in vivo. They are various kinds of carbohydrate formazan derivatives with deduced uni-saccharide (D-glucose, D-mannose and D-galactose) or disaccharide (maltose) and functional group (-COOH, -NH, -OH, -N=N- and pyridyl group). For example of synthesis method of, formazan derivative with maltose was described. 100 mouse with 8 to 10 g were classified to four groups. 1 group get 0.1 ml of nickel ion hemoperitoneum injection once (control). 2 group had 0.1 ml nickel ion hemoperitoneum injection at one time a day and then 0.1 ml eccritic hypodermic injection during 5 days. 3 group get 0.1 ml cadmium ion hemoperitoneum injection once (control). 4 group had 0.1 ml cadmium ion hemoperitoneum injection and then 0.1 ml eccritic hypodermic injection at one time a day for 5 days. Decay of residue was measured. PCF-maltose showed the best chemical protector against radiation in these agents. Especially, this eccritic can excrete 63Ni and 109Cd without effect on the essential metals such as calcium, magnesium and iron. (S.Y.)

  11. Red Yeast Rice Increases Excretion of Bile Acids in Hamsters

    KA-YING MA; ZE-SHENG ZHANG; SHU-XIN ZHAO; QI CHANG; YIN-MEI WONG; SAI YING VENUS YEUNG; YU HUANG; ZHEN-YU CHEN

    2009-01-01

    Objectives To investigate the hypocholesterolemic activity of red yeast rice (RYR) and its underlying mechanism. Methods Three groups of hamsters were fed either the control diet or one of the two experimental diets containing by weight 0.1% RYR (0.1RYR) or 0.3% RYR (0.3RYR). Blood (0.5 mL) was collected from the retro-orbital sinus into a heparinized capillary tube at the end of week 0,3, and 6.Plasma lipoproteins were measured using enzymatic kits, while fecal neutral and acidic sterols were quantified using a gas-liquid chromatography. Results Plasma total cholesterol was reduced by 12% in 0.1RYR group and by 18% in 0.3RYR group compared with the control value. Similarly, plasma triacylglycerol was decreased by ll% in 0.1RYR group and by 24% in 0.3RYR group. Western blotting analysis demonstrated that RYR had no effect on sterol regulatory element binding protein 2, liver X receptor, 3-hydroxy-3-methylglutary-CoA reductase, LDL receptor, and cholesterol-7α-hydroxylase. HPLC analysis confirmed that RYR contained 0.88% monacolin K.It was recently found that RYR supplementation increased excretion of fecal acidic sterols by 3-4 folds compared with the control value. Conclusion Hypocholesterolemic activity of RYR is mediated at least partially by enhancement of acidic sterol excretion.

  12. Retention and excretion of 95Zr-95Nb in humans.

    Thind, K S

    1995-12-01

    This note describes the retention and excretion of 95Zr-95Nb in humans based on a recent CANDU experience and a literature survey of reported cases. Two data bases, QUEST and INIS were used for the survey. Three reported cases were discovered: two for occupational exposures and one for public exposure from nuclear weapons fallout. Human lung retention from these three cases, plus whole body retention and some limited fecal excretion data from a recently occurred exposure at a CANDU station, were reviewed and tested against predictions based on ICRP Publication 30 model. Based on the fits of this model to the reported data it seems that the three occupational exposures exhibit class Y behavior while the public exposure exhibits class W behavior. For only one case is the chemical compound known with certainty: ZrO2. Zirconium oxides are currently classified as class W in ICRP Publications 30 and 54. This work confirms a suggestion that oxides of zirconium be classified as class Y and should be taken into account by the ICRP in its future publications. PMID:7493813

  13. K+ Excretion: The Other Purpose for Puddling Behavior in Japanese Papilio Butterflies

    Inoue, Takashi A.; Ito, Tetsuo; Hagiya, Hiroshi; Hata, Tamako; Asaoka, Kiyoshi; Yokohari, Fumio; Niihara, Kinuko

    2015-01-01

    To elucidate the purpose of butterfly puddling, we measured the amounts of Na+, K+, Ca2+, and Mg2+ that were absorbed or excreted during puddling by male Japanese Papilio butterflies through a urine test. All of the butterflies that sipped water with a Na+ concentration of 13 mM absorbed Na+ and excreted K+, although certain butterflies that sipped solutions with high concentrations of Na+ excreted Na+. According to the Na+ concentrations observed in naturally occurring water sources, water w...

  14. Renal kallikrein excretion and epigenetics in human acute kidney injury: Expression, mechanisms and consequences

    Tolwani Ashita; Khandrika Srikrishna; Malhotra Rakesh; Bouchard Josee; Yan Liying; Rao Fangwen; Biswas Nilima; Mahata Manjula; Mathew Roy O; Shih Pei-an; Kang Sun; Mehta Ravindra L; O'Connor Daniel T

    2011-01-01

    Abstract Background Renal kallikrein (KLK1) synthesis and urinary excretion are reportedly diminished during AKI (acute kidney injury) in animal models, and provision of kallikrein abrogates renal injury in this setting, but data in human AKI is limited. Therefore we first examined KLK1 renal excretion in human AKI, and then probed potential endocrine and epigenetic mechanisms for its alterations. Methods KLK1 enzymatic activity excretion was evaluated in urine from patients with established ...

  15. Renal kallikrein excretion and epigenetics in human acute kidney injury: Expression, mechanisms and consequences

    Kang, Sun; Shih, Pei-an; Mathew, Roy O; Mahata, Manjula; Biswas, Nilima; Rao, Fangwen; Yan, Liying; Bouchard, Josee; Malhotra, Rakesh; Tolwani, Ashita; Khandrika, Srikrishna; Ravindra L. Mehta; O'Connor, Daniel T.

    2011-01-01

    Abstract Background Renal kallikrein (KLK1) synthesis and urinary excretion are reportedly diminished during AKI (acute kidney injury) in animal models, and provision of kallikrein abrogates renal injury in this setting, but data in human AKI is limited. Therefore we first examined KLK1 renal excretion in human AKI, and then probed potential endocrine and epigenetic mechanisms for its alterations. Methods KLK1 enzymatic activity excretion was evaluated in urine from patien...

  16. Association of Urinary Calcium Excretion with Serum Calcium and Vitamin D Levels

    A Rathod; Bonny, O; Guessous, I; Suter, P M; Conen, D; Erne, P; Binet, I; Gabutti, L; Gallino, A; Muggli, F; Hayoz, D; Pechere-Bertschi, A; Paccaud, F.; Burnier, M.; Bochud, M

    2015-01-01

    BACKGROUND AND OBJECTIVES: Population-based data on urinary calcium excretion are scarce. The association of serum calcium and circulating levels of vitamin D [25(OH)D2 or D3] with urinary calcium excretion in men and women from a population-based study was explored. DESIGN, SETTINGS, PARTICIPANTS, & MEASUREMENTS: Multivariable linear regression was used to explore factors associated with square root-transformed 24-hour urinary calcium excretion (milligrams per 24 hours) taken as the dep...

  17. Efficient simultaneous reverse Monte Carlo modeling of pair-distribution functions and extended x-ray-absorption fine structure spectra of crystalline disordered materials

    Németh, Károly; Chapman, Karena W.; Balasubramanian, Mahalingam; Shyam, Badri; Chupas, Peter J.; Heald, Steve M.; Newville, Matt; Klingler, Robert J.; Winans, Randall E.; Almer, Jonathan D.; Sandi, Giselle; Srajer, George

    2012-02-01

    An efficient implementation of simultaneous reverse Monte Carlo (RMC) modeling of pair distribution function (PDF) and EXAFS spectra is reported. This implementation is an extension of the technique established by Krayzman et al. [J. Appl. Cryst. 42, 867 (2009)] in the sense that it enables simultaneous real-space fitting of x-ray PDF with accurate treatment of Q-dependence of the scattering cross-sections and EXAFS with multiple photoelectron scattering included. The extension also allows for atom swaps during EXAFS fits thereby enabling modeling the effects of chemical disorder, such as migrating atoms and vacancies. Significant acceleration of EXAFS computation is achieved via discretization of effective path lengths and subsequent reduction of operation counts. The validity and accuracy of the approach is illustrated on small atomic clusters and on 5500-9000 atom models of bcc-Fe and α-Fe2O3. The accuracy gains of combined simultaneous EXAFS and PDF fits are pointed out against PDF-only and EXAFS-only RMC fits. Our modeling approach may be widely used in PDF and EXAFS based investigations of disordered materials.

  18. Tunable diode laser absorption spectroscopy-based tomography system for on-line monitoring of two-dimensional distributions of temperature and H{sub 2}O mole fraction

    Xu, Lijun, E-mail: lijunxu@buaa.edu.cn; Liu, Chang; Jing, Wenyang; Cao, Zhang [School of Instrument Science and Opto-Electronic Engineering, Beihang University, Beijing 100191 (China); Ministry of Education’s Key Laboratory of Precision Opto-Mechatronics Technology, Beijing 100191 (China); Xue, Xin; Lin, Yuzhen [School of Energy and Power Engineering, Beihang University, Beijing 100191 (China)

    2016-01-15

    To monitor two-dimensional (2D) distributions of temperature and H{sub 2}O mole fraction, an on-line tomography system based on tunable diode laser absorption spectroscopy (TDLAS) was developed. To the best of the authors’ knowledge, this is the first report on a multi-view TDLAS-based system for simultaneous tomographic visualization of temperature and H{sub 2}O mole fraction in real time. The system consists of two distributed feedback (DFB) laser diodes, a tomographic sensor, electronic circuits, and a computer. The central frequencies of the two DFB laser diodes are at 7444.36 cm{sup −1} (1343.3 nm) and 7185.6 cm{sup −1} (1391.67 nm), respectively. The tomographic sensor is used to generate fan-beam illumination from five views and to produce 60 ray measurements. The electronic circuits not only provide stable temperature and precise current controlling signals for the laser diodes but also can accurately sample the transmitted laser intensities and extract integrated absorbances in real time. Finally, the integrated absorbances are transferred to the computer, in which the 2D distributions of temperature and H{sub 2}O mole fraction are reconstructed by using a modified Landweber algorithm. In the experiments, the TDLAS-based tomography system was validated by using asymmetric premixed flames with fixed and time-varying equivalent ratios, respectively. The results demonstrate that the system is able to reconstruct the profiles of the 2D distributions of temperature and H{sub 2}O mole fraction of the flame and effectively capture the dynamics of the combustion process, which exhibits good potential for flame monitoring and on-line combustion diagnosis.

  19. ABSORPTION AND BIOAVAILABILITY OF THE MINERALS IN THE MULTI-MIXTURE FOOD SUPPLEMENT: BIOLOGICAL ASSAY IN RATS

    E. HELBIG

    2008-12-01

    Full Text Available

    The absorption and bioavailability of the minerals Ca, Fe and Zn in balanced and mineral restricted diets with the addition of the food supplement multi-mixture (MM, was evaluated. A biological assay was carried out for 28 days with recently weaned Wistar rats, using 3 treatments and 8 animals in each group. The diets offered to each group were distributed as follows: CD – Control Diet (AIN-93G; CcD/MM – Control Diet + Supplement 5% MM; DRMIXc/MM – Control Diet with Mineral Restricted + Supplement 5% MM. The animals were monitored for weight; amount of diet consumed and amount of faeces excreted. They were sacrifi ced at the end of the experimental period and the pair of femurs, pancreas and liver removed for the determination of Ca, Fe and Zn. The CcD/MM diet presented absorption of Ca and Fe and bioavailability of Ca, Fe and Zn equal to that of CD, showing no statistical difference between the treatments. However the DRMIXcD/MM diet presented an increase in Ca absorption, equal absorption of Fe and an increase in the bioavailability of Ca, Fe and Zn when compared to CD. It was concluded that when fed on a balanced diet supplemented with 5% MM, there was no increase in the bioavailability of Ca, Fe or Zn, whereas when fed on a mineral defi cient diet, the group of animals that received supplementation with 5% MM, presented greater absorption and bioavailability of these minerals.

  20. Nitrogen excretion during embryonic development of the green iguana, Iguana iguana (Reptilia; Squamata).

    Sartori, M R; Taylor, E W; Abe, A S

    2012-10-01

    Development within the cleidoic egg of birds and reptiles presents the embryo with the problem of accumulation of wastes from nitrogen metabolism. Ammonia derived from protein catabolism is converted into the less toxic product urea or relatively insoluble uric acid. The pattern of nitrogen excretion of the green iguana, Iguana iguana, was determined during embryonic development using samples from allantoic fluid and from the whole homogenized egg, and in hatchlings and adults using samples of blood plasma. Urea was the major excretory product over the course of embryonic development. It was found in higher concentrations in the allantoic sac, suggesting that there is a mechanism present on the allantoic membrane enabling the concentration of urea. The newly hatched iguana still produced urea while adults produced uric acid. The time course of this shift in the type of nitrogen waste was not determined but the change is likely to be related to the water relations associated with the terrestrial habit of the adult. The green iguana produces parchment-shelled eggs that double in mass during incubation due to water absorption; the eggs also accumulate 0.02 mM of urea, representing 82% of the total measured nitrogenous residues that accumulate inside the allantois. The increase in egg mass and urea concentration became significant after 55 days of incubation then were unchanged until hatching. PMID:22710252

  1. Comparison of endogenous and radiolabeled bile acid excretion in patients with idiopathic chronic diarrhea

    Schiller, L.R.; Bilhartz, L.E.; Santa Ana, C.A. (Baylor Univ. Medical Center, Dallas, TX (USA))

    1990-04-01

    Fecal recovery of radioactivity after ingestion of a bolus of radiolabeled bile acid is abnormally high in most patients with idiopathic chronic diarrhea. To evaluate the significance of this malabsorption, concurrent fecal excretion of both exogenous radiolabeled bile acid and endogenous (unlabeled) bile acid were measured in patients with idiopathic chronic diarrhea. Subjects received a 2.5-microCi oral dose of taurocholic acid labeled with 14C in the 24th position of the steroid moiety. Endogenous bile acid excretion was measured by a hydroxysteroid dehydrogenase assay on a concurrent 72-h stool collection. Both radiolabeled and endogenous bile acid excretion were abnormally high in most patients with chronic diarrhea compared with normal subjects, even when equivoluminous diarrhea was induced in normal subjects by ingestion of osmotically active solutions. The correlation between radiolabeled and endogenous bile acid excretion was good. However, neither radiolabeled nor endogenous bile acid excretion was as abnormal as is typically seen in patients with ileal resection, and none of these diarrhea patients responded to treatment with cholestyramine with stool weights less than 200 g. These results suggest (a) that this radiolabeled bile acid excretion test accurately reflects excess endogenous bile acid excretion; (b) that excess endogenous bile acid excretion is not caused by diarrhea per se; (c) that spontaneously occurring idiopathic chronic diarrhea is often associated with increased endogenous bile acid excretion; and (d) that bile acid malabsorption is not likely to be the primary cause of diarrhea in most of these patients.

  2. Comparison of endogenous and radiolabeled bile acid excretion in patients with idiopathic chronic diarrhea

    Fecal recovery of radioactivity after ingestion of a bolus of radiolabeled bile acid is abnormally high in most patients with idiopathic chronic diarrhea. To evaluate the significance of this malabsorption, concurrent fecal excretion of both exogenous radiolabeled bile acid and endogenous (unlabeled) bile acid were measured in patients with idiopathic chronic diarrhea. Subjects received a 2.5-microCi oral dose of taurocholic acid labeled with 14C in the 24th position of the steroid moiety. Endogenous bile acid excretion was measured by a hydroxysteroid dehydrogenase assay on a concurrent 72-h stool collection. Both radiolabeled and endogenous bile acid excretion were abnormally high in most patients with chronic diarrhea compared with normal subjects, even when equivoluminous diarrhea was induced in normal subjects by ingestion of osmotically active solutions. The correlation between radiolabeled and endogenous bile acid excretion was good. However, neither radiolabeled nor endogenous bile acid excretion was as abnormal as is typically seen in patients with ileal resection, and none of these diarrhea patients responded to treatment with cholestyramine with stool weights less than 200 g. These results suggest (a) that this radiolabeled bile acid excretion test accurately reflects excess endogenous bile acid excretion; (b) that excess endogenous bile acid excretion is not caused by diarrhea per se; (c) that spontaneously occurring idiopathic chronic diarrhea is often associated with increased endogenous bile acid excretion; and (d) that bile acid malabsorption is not likely to be the primary cause of diarrhea in most of these patients

  3. Pion absorption processes

    Proton and deuteron production from low-energy pion absorption in light nuclei leading to discrete and continuum states were measured. The LEP beam line at LAMPF was used with a stack of 8 intrinsic germanium crystals. The proton energy spectra are in general characterized by a broad bump at an energy approximately corresponding to π+d → pp reaction kinematics, suggestive of pion absorption on 2 nucleons. The energy-integrated cross-section for production of deuterons has an angular distribution similar to that for production of protons. The dependence of the total pion absorption cross-section on A is explained using a semi-classical model for pion transport in nuclei. The (π+,p) as well as (π+,d) reactions generally favor transitions involving larger angular momentum transfer to the residual nucleus when states of similar nuclear structure are considered. The low-energy excitation spectra from the (π+,p) reaction are similar to the spectra from (p,d) reaction on 12C and 13C. However, a calculation of the (π+,p) cross-section using the measured (p,d) reaction with the formulation of Wilkin to relate the two reactions is in moderate disagreement with the measured (π+,p) cross-sections. The excitation spectra from the (π+,p) reaction indicte the importance of two-step processes for the reaction. The (π+,d) reaction leading to the ground state of -- residual nucleus has been seen for 7Li, 12C, and 13C targets. The measured cross section for the 12C(π+,d)10C reaction to the 2+ state is much higher than that for the ground state. For the case of 18O, no counts were seen for excitation energy of +,d) reaction

  4. Measurement of the rate of fat absorption by the 14C-triolein breath test

    To characterize the extent to which continuous measurement of the rate of 14CO2 excretion following the oral administration of 14C-labeled triolein (14C-T) would estimate the rate of absorption of triolein by the gut, ten adult male rats were fed 0.5 ml of 14C-T and the rate of production of expired labeled CO2 was measured continuously. Pairs of animals were sacrificed at 30 min intervals between 90 and 210 min and absorption rates were calculated by quantitating substrate remaining in the gut. Comparison of these rates with the cumulative excretion rates of labeled CO2 revealed a linear relationship with a correlation coefficient of 0.91. In a second experiment, adult rats received an intravenous injection of Triton WR-1339, a potent inhibitor of lipoprotein lipase, prior to receiving 14C-T. The rate of intestinal 14C-triglyceride output was determined from the increase in 14C in the blood over a 6 hr period. Comparison of the rates of intestinal secretion using Triton WR-1339 with that determined from the cumulative rates of excretion of 14CO2 revealed a correlation coefficient of 0.98. The authors conclude that rates of triglyceride absorption can be estimated in vivo by the continuous measurement of labeled CO2 excreted in breath

  5. Urinary albumin excretion. An independent predictor of ischemic heart disease

    Borch-Johnsen, K; Feldt-Rasmussen, B; Strandgaard, S;

    1999-01-01

    ischemic heart disease (IHD) in a population-based cohort. In 1983, urinary albumin and creatinine levels were measured, along with the conventional atherosclerotic risk factors, in 2085 consecutive participants without IHD, renal disease, urinary tract infection, or diabetes mellitus. The participants......Cross-sectional studies suggest that an increased urinary albumin excretion rate is associated with cardiovascular disease, dyslipidemia, and hypertension. The purpose of this study was to analyze prospectively whether the urinary albumin-to -creatinine (A/C) ratio can independently predict......, 1.3 to 3.9, P=0.002), and the 10-year disease-free survival decreased from 97% to 91% (P<0.0001) when microalbuminuria was present. An interaction between microalbuminuria and smoking was observed, and the presence of microalbuminuria more than doubled the predictive effect of the conventional...

  6. Very rapid bolus injection as routine method in excretion urography

    Weigert, F.; Wehweck, H.; Eggemann, F.

    1982-09-01

    The authors report on a comparative examination of the tolerance and diagnostic value of excretion urography using a standard dose of 50 ml of a 77% solution of the meglumine-sodium salt of ioxythalamic acid (Telebrix 380) at conventional injection speed (60-90 sec.) compared with a very rapid bolus injection (less than 10 sec.) Although the risk of severe side effects is probably the same in both cases, the rate of mild or so-called non-specific side effects is significantly lower with the more rapid type of injection. At the same time, it is possible to improve the diagnostic value with a slightly greater effort (vascular early nephrogram.

  7. Very rapid bolus injection as routine method in excretion urography

    The authors report on a comparative examination of the tolerance and diagnostic value of excretion urography using a standard dose of 50 ml of a 77% solution of the meglumine-sodium salt of ioxythalamic acid (Telebrix 380) at conventional injection speed (60-90 sec.) compared with a very rapid bolus injection (less than 10 sec.) Although the risk of severe side effects is probably the same in both cases, the rate of mild or so-called non-specific side effects is significantly lower with the more rapid type of injection. At the same time, it is possible to improve the diagnostic value with a slightly greater effort (vascular early nephrogram. (orig.)

  8. Excretion of ciprofloxacin in sweat and multiresistant Staphylococcus epidermidis

    Høiby, N; Jarløv, J O; Kemp, M;

    1997-01-01

    BACKGROUND: Staphylococcus epidermidis develops resistance to ciprofloxacin rapidly. That this antibiotic is excreted in apocrine and eccrine sweat of healthy individuals might be the reason for the development of such resistance. We assessed whether S epidermidis isolated from the axilla and nasal...... flora of healthy people could develop resistance to ciprofloxacin after a 1-week course of this antibiotic. METHODS: The concentration of ciprofloxacin in sweat was measured in seven volunteers after oral administration of 750 mg ciprofloxacin twice daily for 7 days, and the development of resistance in...... S epidermidis from axilla and nostrils was monitored during and 2 months after the treatment. Genotyping of S epidermidis was done by restriction fragment length polymorphism. FINDINGS: The mean concentration of ciprofloxacin in sweat increased during the 7 days of treatment-from 2.2 micrograms/mL 2...

  9. LOW FRACTIONAL EXCRETION OF UREA IN HYPOTHYROIDISM INDUCED HYPONATREMIA

    Algranati L

    2005-01-01

    Full Text Available RESUMEN:El hipotiroidismo puede causar alteraciones del metabolismo del agua, los electrolitos, la hemodinamia e histología renales, siendo la hiponatremia y la reducción del filtrado glomerular sus consecuencias más significativas, pero poco prevalentes. Todos estos cambios son corregibles con el suministro de hormona tiroidea exógena.La excreción fraccional de urea (EFU es un índice útil en la evaluación de la hiponatremia, pero no se ha descripto aun el valor que este índice alcanza en la hiponatremia inducida por hipotiroidismo. En el presente reporte mostramos que la EFU y excreción fraccional de sodio (EFNa fueron baja (EFU: 29% y alta (EFNa: 2.2% respectivamente en un paciente que padecía hipotiroideo severo. El tratamiento con hormona tiroidea normalizó el valor de ambos índices.ABSTRACTHypothyroidism can cause disturbance of renal hemodinamics, kidney histology, water and electrolyte metabolism, being hyponatremia and glomerular filtration reduction their low prevalent but most significant consequences. All these changes are largely corrected by substitution of exogenous thyroid hormone.Fractional excretion of urea (FEU is a useful index in the evaluation of hyponatremia. However, it was not still reported in the literature the FEU value in hyponatremia induced by hypothyroidism. Because of that we presented a case report showing that the value of FEU and fractional excretion of sodium (FENa were low (FEU: 29% and high (FENa: 2.2 % respectively in a severe hypothyroid patient. Treatment based on thyroid hormone normalized both indeces.

  10. Uptake, excretion, and radiation hazards of tritiated thymidine in humans

    Nine patients with malignant disease were given iv injections of tritiated thymidine, 0.2 mCi/kg, for tumor cell kinetics studies. Serial plasma, urine, saliva, and air vapor samples were collected variously for up to 79 days, and tritium activity was measured. The initial half-life of plasma activity was rapid. After 1 day, the activity decayed with a half-life of 10.8 days, indicating equilibration of activity with the total body water. Urine activity was over 100 times the plasma activity within 1 hr, with equilibration approaching the plasma activity after 2 days, and then decayed at a similar rate. Saliva and air vapor activity increased to plasma levels and then decayed at the same rate as did plasma activity. In the first 24 hr, approximately one-third of the total injected activity was excreted in the urine. During the first 12 days there were 54.2% urinary and 10.6% insensible losses. Maximum losses determined by extrapolation of observed data were 68% urinary and 19.5% insensible losses, or a total of 87.5%. Approximately 7% of the injected activity may represent material initially incorporated into DNA but later metabolized and excreted. The radiation dose from total body water is estimated at 0.69 rad. The estimated dose absorbed by cell nuclei from incorporated material is a maximum of 20.5 rads. These radiation doses would not seem to contraindicate injection of 0.2 mCi tritiated thymidine per kg to patients in this clinical and experimental setting. Measurements of activity in personnel and room air indicate that the use of such doses is not hazardous if appropriate precautions are followed

  11. QSAR analysis of drug excretion into human breast milk.

    Meskin, M S; Lien, E J

    1985-09-01

    Breast feeding has increased by approximately 25% in the United States during the past decade and this trend appears to be continuing. The number of drugs available to lactating women is also growing at a rapid pace. The excretion of drugs into breast-milk presents a potential danger to infants. In spite of this, little is known about the excretion of drugs into breast-milk. The ability to predict which drugs are potential hazards would be very useful in the clinical setting. This study quantitatively correlates the human milk to plasma concentration ratio of various basic and acidic drugs (log M/P) with the square root of the molecular weight, the partition coefficient (log P) and the degree of dissociation (log U/D). For basic drugs there is a negative-dependence on both log P and log U/D. High lipophilicity favours protein binding and reduces the amount of drug available for diffusion into milk. Therefore, as log P increases, the log M/P decreases. The negative-dependence on log U/D indicates that the higher the degree of dissociation of the base in plasma, the greater the log M/P will be. This fits well with the concept of ion-trapping. A strong base is more likely to be transferred and then trapped in milk which has a lower pH than plasma. For acidic drugs there is a negative-dependence on both square root (MW) and log P. The negative-dependence on square root (MW) suggests that large molecules are less likely to be able to diffuse into the milk. A negative-dependence on log P appears to hold true for bases and acids. Log M/P decreases as log P increases. This is probably due to increased protein binding by lipophilic drugs through non-specific hydrophobic interaction with plasma protein. PMID:4066977

  12. Fecal calprotectin excretion in preterm infants during the neonatal period.

    Carole Rougé

    Full Text Available BACKGROUND: Fecal calprotectin has been proposed as a non-invasive marker of intestinal inflammation in inflammatory bowel disease in adults and children. Fecal calprotectin levels have been reported to be much higher in both healthy full-term and preterm infants than in children and adults. OBJECTIVE: To determine the time course of fecal calprotectin (f-calprotectin excretion in preterm infants from birth until hospital discharge and to identify factors influencing f-calprotectin levels in the first weeks of life, including bacterial establishment in the gut. METHODOLOGY: F-calprotectin was determined using an ELISA assay in 147 samples obtained prospectively from 47 preterm infants (gestational age, and birth-weight interquartiles 27-29 weeks, and 880-1320 g, respectively at birth, and at 2-week intervals until hospital discharge. PRINCIPAL FINDINGS: Although median f-calprotectin excretion was 138 microg/g, a wide range of inter- and intra-individual variation in f-calprotectin values (from day 3 to day 78 was observed (86% and 67%, respectively. In multivariate regression analysis, f-calprotectin correlated negatively with ante and per natal antibiotic treatment (p = 0.001, and correlated positively with the volume of enteral feeding (mL/kg/d (p = 0.009, the need to interrupt enteral feeding (p = 0.001, and prominent gastrointestinal colonization by Clostridium sp (p = 0.019 and Staphylococcus sp (p = 0.047. CONCLUSION: During the first weeks of life, the high f-calprotectin values observed in preterm infants could be linked to the gut bacterial establishment.

  13. Fecal Calprotectin Excretion in Preterm Infants during the Neonatal Period

    Rougé, Carole; Butel, Marie-José; Piloquet, Hugues; Ferraris, Laurent; Legrand, Arnaud; Vodovar, Michel; Voyer, Marcel; de la Cochetière, Marie-France; Darmaun, Dominique; Rozé, Jean-Christophe

    2010-01-01

    Background Fecal calprotectin has been proposed as a non-invasive marker of intestinal inflammation in inflammatory bowel disease in adults and children. Fecal calprotectin levels have been reported to be much higher in both healthy full-term and preterm infants than in children and adults. Objective To determine the time course of fecal calprotectin (f-calprotectin) excretion in preterm infants from birth until hospital discharge and to identify factors influencing f-calprotectin levels in the first weeks of life, including bacterial establishment in the gut. Methodology F-calprotectin was determined using an ELISA assay in 147 samples obtained prospectively from 47 preterm infants (gestational age, and birth-weight interquartiles 27–29 weeks, and 880–1320 g, respectively) at birth, and at 2-week intervals until hospital discharge. Principal Findings Although median f-calprotectin excretion was 138 µg/g, a wide range of inter- and intra-individual variation in f-calprotectin values (from day 3 to day 78) was observed (86% and 67%, respectively). In multivariate regression analysis, f-calprotectin correlated negatively with ante and per natal antibiotic treatment (p = 0.001), and correlated positively with the volume of enteral feeding (mL/kg/d) (p = 0.009), the need to interrupt enteral feeding (p = 0.001), and prominent gastrointestinal colonization by Clostridium sp (p = 0.019) and Staphylococcus sp (p = 0.047). Conclusion During the first weeks of life, the high f-calprotectin values observed in preterm infants could be linked to the gut bacterial establishment. PMID:20552029

  14. Ammonia production, excretion, toxicity, and defense in fish: A Review

    Alex Y K Ip

    2010-10-01

    Full Text Available Many fishes are ammonotelic but some species can detoxify ammonia to glutamine or urea. Certain fish species can accumulate high levels of ammonia in the brain or defense against ammonia toxicity by enhancing the effectiveness of ammonia excretion through active NH4+ transport, manipulation of ambient pH, or reduction in ammonia permeability through the branchial and cutaneous epithelia. Recent reports on ammonia toxicity in mammalian brain reveal the importance of permeation of ammonia through the blood-brain barrier and passages of ammonia and water through transporters in the plasmalemma of brain cells. Additionally, brain ammonia toxicity could be related to the passage of glutamine through the mitochondrial membranes into the mitochondrial matrix. On the other hand, recent reports on ammonia excretion in fish confirm the involvement of Rhesus glycoproteins in the branchial and cutaneous epithelia. Therefore, this review focuses on both the earlier literature and the up-to-date information on the problems and mechanisms concerning the permeation of ammonia, as NH3, NH4+ or proton-neutral nitrogenous compounds, across mitochondrial membranes, the blood-brain barrier, the plasmalemma of neurons, and the branchial and cutaneous epithelia of fish. It also addresses how certain fishes with high ammonia tolerance defend against ammonia toxicity through the regulation of the permeation of ammonia and related nitrogenous compounds through various types of membranes. It is hoped that this review would revive the interests in investigations on the passage of ammonia through the mitochondrial membranes and the blood-brain barrier of ammonotelic fishes and fishes with high brain ammonia-tolerance, respectively.

  15. High-fiber rye diet increases ileal excretion of energy and macronutrients compared with low-fiber wheat diet independent of meal frequency in ileostomy subjects

    Isaksson, Hanna; Landberg, Rikard; Sundberg, Birgitta; Lundin, Eva; Hallmans, Göran; Zhang, Jie- Xian; Tidehag, Per; Bach Knudsen, Knud Erik; Moazzami, Ali A; Åman, Per

    2013-01-01

    Background:Whole-grain foods and cereal dietary fiber intake is associated with lower body weight. This may partly result from lower energy utilization of high-fiber diets.Objective: In the present study, the impact on ileal excretion of energy and macronutrients in response to a rye bread high-fiber diet compared to a refined wheat low-fiber diet was investigated. Furthermore, the effect of meal frequency on apparent absorption of nutrients was studied for the first time.Design: Ten particip...

  16. Dietary ɛ-Polylysine Decreased Serum and Liver Lipid Contents by Enhancing Fecal Lipid Excretion Irrespective of Increased Hepatic Fatty Acid Biosynthesis-Related Enzymes Activities in Rats.

    Hosomi, Ryota; Yamamoto, Daiki; Otsuka, Ren; Nishiyama, Toshimasa; Yoshida, Munehiro; Fukunaga, Kenji

    2015-03-01

    ɛ-Polylysine (EPL) is used as a natural preservative in food. However, few studies have been conducted to assess the beneficial functions of dietary EPL. The purpose of this study was to elucidate the mechanism underlying the inhibition of neutral and acidic sterol absorption and hepatic enzyme activity-related fatty acid biosynthesis following EPL intake. EPL digest prepared using an in vitro digestion model had lower lipase activity and micellar lipid solubility and higher bile acid binding capacity than casein digest. Male Wistar rats were fed an AIN-93G diet containing 1% (wt/wt) EPL or l-lysine. After 4 weeks of feeding these diets, the marked decrease in serum and liver triacylglycerol contents by the EPL diet was partly attributed to increased fecal fatty acid excretion. The activities of hepatic acetyl-coenzyme A carboxylase and glucose-6-phosphate dehydrogenase, which are key enzymes of fatty acid biosynthesis, were enhanced in rats fed EPL diet. The increased fatty acid biosynthesis activity due to dietary EPL may be prevented by the enhancement of fecal fatty acid excretion. The hypocholesterolemic effect of EPL was mediated by increased fecal neutral and acidic sterol excretions due to the EPL digest suppressing micellar lipid solubility and high bile acid binding capacity. These results show that dietary EPL has beneficial effects that could help prevent lifestyle-related diseases such as hyperlipidemia and atherosclerosis. PMID:25866749

  17. Tissue contents and urinary excretion of taurine after administration of L-cysteine and L-2-oxothiazolidine-4-carboxylate to rats.

    Ubuka,Toshihiko

    1990-06-01

    Full Text Available Tissue contents and urinary excretion of taurine were studied in rats after the administration of L-cysteine and its derivatives. Average taurine content in the liver of rats fed a 25% casein diet for 7 days increased 2-fold 2h after the intraperitoneal administration of 5 mmol of L-cysteine per kg of body weight, whereas that in rats fed a 5% casein diet for 2 days increased only slightly. The difference in the liver taurine contents between these two groups was discussed in relation to cysteine dioxygenase. Taurine contents in the heart, brain and blood did not differ significantly between these two groups or between the control and the group of rats which received L-cysteine. The increase in liver taurine concentrations after L-cysteine administration was much higher than that after L-cystine administration, suggesting a difference in their absorption. The intraperitoneal administration of 5 mmol/kg of L-2-oxothiazolidine-4-carboxylate (OTCA resulted in a 3-fold increase in liver taurine content. The average increase in taurine excretion in the 24-h urine after OTCA administration corresponded to about 6.0% and that in the next 24-h urine to about 2.6% of OTCA administered, suggesting that nearly 10% of OTCA was metabolized to taurine and excreted in the urine.

  18. Biliary excretion of platinum in a patient treated with cis-dichlorodiammineplatinum (II).

    Shelley, M. D.; Fish, R. G.; Adams, M.

    1985-01-01

    Biliary excretion of platinum was measured in a patient receiving an intravenous infusion of cis-dichlorodiammineplatinum (II). Over a 3-day period, less than 1% of the administered platinum was detected in the bile, and 47% appeared in the urine, indicating that biliary excretion is a minor route of elimination.

  19. Dietary strategies to reducing N excretion from cattle: implications for methane emissions

    Dijkstra, J.; Oenema, O.; Bannink, A.

    2011-01-01

    Ruminants turn human inedible into human edible products, but at a cost of excretion of various pollutants. Implications of dietary measures for cattle to reduce faecal and urinary nitrogen losses on methane emissions are reviewed. Reducing the dietary protein content decreases nitrogen excretion in

  20. Finding the cause of acute kidney injury: which index of fractional excretion is better?

    Gotfried, Jonathan; Wiesen, Jonathan; Raina, Rupesh; Nally, Joseph V

    2012-02-01

    The fractional excretion of urea (FEU) is a useful index for differentiating the main categories of causes of acute kidney injury, ie, prerenal causes and intrinsic causes. It may be used in preference to the more widely used fractional excretion of sodium (FENa) in situations in which the validity of the latter is limited, such as in patients taking a diuretic. PMID:22301562

  1. Urinary excretion of arsenicals following daily intake of various seafoods during a two weeks intervention

    Molin, M.; Ulven, S.M.; Dahl, L.;

    2014-01-01

    the intervention. Confirming the single dose study AB and DMA excreted were apparently endogenously formed from other arsenicals ingested. Total tAs excretion was 1386, 763 and 303μg in the cod, blue mussel and salmon groups, respectively; about twice the amounts after the single dose study indicating...

  2. Increased urinary orosomucoid excretion predicts preeclampsia in pregnant women with pregestational type 1 diabetes

    Hesse, D; Ekbom, P; Hesse, U; Damm, P; Hommel, E; Feldt-Rasmussen, B; Mathiesen, E; Christiansen, MS

    2010-01-01

    We evaluated the urinary orosomucoid excretion (UOE) as a biomarker of preeclampsia and preterm delivery in pregnant women with type 1 diabetes.......We evaluated the urinary orosomucoid excretion (UOE) as a biomarker of preeclampsia and preterm delivery in pregnant women with type 1 diabetes....

  3. Effect of low-dose heparin on urinary albumin excretion in insulin-dependent diabetes mellitus

    Myrup, B; Hansen, P M; Jensen, T;

    1995-01-01

    We investigated the effect of heparin on urinary albumin excretion in patients with insulin-dependent diabetes mellitus. 39 patients with persistent urinary albumin excretion of 30-300 mg/24 h were randomly treated for 3 months with subcutaneous injections twice daily of isotonic saline, 5000 IU...

  4. Feasibility of ICP-MS for the assessment of uranium excretion in urine

    Inductively coupled plasma mass spectrometry (ICP-MS) has been applied to the assessment of urinary uranium excretion in non-exposed subjects. The sensitivity of the method is high enough to determine 238U concentration in unprocessed urine in any subject. Data obtained so far show a significant increase of 238U excretion with age and no differences between males and females. (author)

  5. Absorption and metabolic fate of bioactive dietary benzoxazinoids in humans

    Adhikari, Khem B; Laursen, Bente B; Gregersen, Per L;

    2013-01-01

    Scope Benzoxazinoids, which are natural compounds recently identified in mature whole grain cereals and bakery products, have been suggested to have a range of pharmacological properties and health-protecting effects. There are no published reports concerned with the absorption and metabolism of...... bioactive benzoxazinoids in humans. Methods and results The absorption, metabolism, and excretion of ten different dietary benzoxazinoids were examined by LC-MS/MS by analyzing plasma and urine from 20 healthy human volunteers after daily intake of 143 μmol of total benzoxazinoids from rye bread and rye...... benzoxazinoids with abundant HBOA-Glc (219 nmol × μmol−1 of creatinine). The sulfate and glucuronide conjugates of 2-hydroxy-1,4-benzoxazin-3-one (HBOA) and 2,4-dihydroxy-1,4-benzoxazin-3-one (DIBOA) were detected in plasma and urine, indicating substantial phase II metabolism. Direct absorption of lactam...

  6. Non-invasive Sampling Strategy for Monitoring Free-ranging Mountain Gorilla (Gorilla berengi berengi) Fecal Corticoid Excretion in Bwindi Impenetrable National Park, South-Western Uganda

    J.B. Nizeyi; S.L. Monfort, N.M. Taha, M. Cranfield and K. Gilardi

    2011-01-01

    Health monitoring of the critically endangered mountain gorilla (Gorilla berengei berengei) as one of the strategies for their conservation requires establishment of non-invasive methods that do not interfere with their natural behaviors. Therefore a fecal sampling strategy was established for use in assessing their adrenocortical activity non-invasively by investigating corticoid distribution along the fecal strand, possible existence of fecal corticoid excretion rhythms and environmental ef...

  7. Diagnostic value of determination of amount of urinary excretion of proteins for early diabetic nephropathy

    Objective: To investigate the value of detection of changes of the amount of usinary excretion of albumin, β2-m, Tamm- Horsfall protein and α1-m for diagnosis of early diabetic nephropathy. Methods: The amounts of 24h urinary excretion of albumin, β2-m, Tamm-Horsfall protein and α1-m were determined with RIA in 78 patients with diabetes mellitus and 40 controls. Results: The amounts of 24h urinary excretion of albumin, β2-m, α1-m in patients with diabetes mellitus were significantly higher than those in controls (P<0.01 ), while the amount of Tamm-Horsfall protein was significantly lower (P<0.01). Among the diabetic patients, the changes of the amount of protein excretion were more pronounced in those with advanced impairment of renal function. Conclusion: Determination of amount of urinary excretion of proteins was helpful for diagnosis and assessment of early diabetic nephropathy. (authors)

  8. Effects of water deprivation on renal hydroelectrolytic excretion in chronically Trypanosoma cruzi-infected rats

    T.T. Rosa

    1995-03-01

    Full Text Available The effect of an 8 hour-period of water deprivation on fluid and electrolyte renal excretion was investigated in male Wistar rats infected with the strain São Felipe (12SF of Trypanosoma cruzi, in comparison with age and sex matched non-infected controls. The median percent reductions in the urinary flow (-40% v -63% and excretion ofsodium (-57% v-79% were smaller in chagasic than in control rats, respectively. So, chagasic rats excreted more than controls. On the other hand, the median percent decrement in the clearance of creatinine was higher in chagasic (-51% than in controls (-39%. Thus, chagasic rats showed some disturbed renal hydroelectrolytic responses to water deprivation, expressed by smaller conservation, or higher excretion of water and sodium in association with smaller glomerularfiltration rate. This fact denoted an elevation in the fractional excretion of sodium and water.

  9. The Effect of Grape Seed Proanthocyanidin Extract (GSPE on Urinary Sodium Excretion

    Gulsum Ozkan

    2013-10-01

    Full Text Available Aim: While various hormones and mediators reduce the urinary excretion of Na, other mediators such as nitric oxide (NO increase Na excretion. Grape seed proanthocyanidin extract (GSPE is a molecule that has an antioxidant effect by increasing NO levels. Our study was intended to evaluate the effect of GSPE on Na excretion. Material and Method: Fourteen rats were divided into control and GSPE groups. The control group was given 1 cm3 milk by gavage for one week, while the GSPE group was given 100 mg/kg GSPE. Seventh-day urines were collected from rats monitored over 24 h in a metabolic cage. Urinary Na excretion at the end of 24 h was investigated and the experiment concluded. Results: There was no difference between the control and GSPE groups in terms of weight, solid and liquid food intake and urine volumes. 24-hour urinary Na excretion was higher in the GSPE group (1.43±0.30 g/day compared to the control group (1.37±0.29 g/day, although the difference was not statistically significant. Na excretion was positively correlated with solid food intake (p=0.029, r=0.583  and urine volume (p<0.001, r=0.806. Discussion: Our study shows, for the first time in the literature, that GSPE increases  urinary Na excretion in healthy rats,  though not to a statistically significant extent, and that solid food intake and urine volume affect Na excretion. We think that it will be useful for the effect of GSPE on urinary Na excretion in hypertensive rats with impaired Na excretion and balance to be evaluated in future studies.

  10. 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.)

  11. D-xylose absorption

    D-xylose absorption is a laboratory test to determine how well the intestines absorb a simple sugar (D-xylose). The test ... test is primarily used to determine if nutrient absorption problems are due to a disease of the ...

  12. D-xylose absorption

    ... this page: //medlineplus.gov/ency/article/003606.htm D-xylose absorption To use the sharing features on this page, please enable JavaScript. D-xylose absorption is a laboratory test to determine ...

  13. Urinary excretion of purine derivatives as an index of microbial protein supply in cross-bred (Bos indicus x Bos taurus) cattle in tropical environment

    Four experiments were carried out to establish a response model between urinary excretion of purine derivatives (PD) and microbial production in Bos indicus x Bos taurus cross-bred cattle: LZ, MZ and HZ (3/8, 1/2 and 5/8 Bos indicus, respectively). The fasting PD excretion was considered as endogenous excretion and amounted to 268 (± 85.1), 294 (± 128.1) and 269 (± 68.4) μmol/kg W0.75 for LZ, MZ and HZ, respectively. Urinary recovery of absorbed purine bases (PB) was calculated as the urinary recovery of a single dose of intrajugular infused uric acid (1,3-15N). In HZ crossbred cattle 83% (± 20.3) of infused uric acid was recovered in the urinary PD. The relationship between duodenal purine absorption (X, mmol/d) and urinary PD excretion (Y, mmol/d) was defined in HZ crossbred cattle as Y = 0.83 X + 0.269W0.75 (± 85.1), assuming that the endogenous contribution was constant and independent of the exogenous PB supply. The activity of xanthine oxidase (EC 1.2.3.2.) was determined in HZ and MZ and was found to be higher in the liver (0.62 and 0.66 units/g, respectively) than in intestinal mucosa (0.09 and 0.03 units/g, respectively), whereas xanthine oxidase activity was practically absent in plasma of both cross breeds. The ratio PB:total N was determined in microbial extracts taken from rumen fluid of cows fed Bermuda grass (Cynodon dactylon) as the sole diet or supplemented (ratio of 80:20, grass: supplement) with gluten feed, soybean hulls or Gliricidia species and were found to range from 1.52-1.62 μmol PB/mg N. (author)

  14. A useful method to evaluate 11C-methionine uptake using positron emission tomography. Determination of the optimal scanning time for evaluation and a comparison between the tumor-to-muscle ratio and the distribution absorption ratio

    We determined the optimal scanning time for evaluating 11C-methionine uptake and then compared the usefulness of the tumor-to-muscle ratio (TMR) with the distribution absorption ratio (DAR) using positron emission tomography. Forty-two PET studies were performed to examine 42 tumorous lesions, 25 normal lung tissues, 23 normal bone marrow and 39 blood pool. In the 42 lesions examined, the TMR at 5, 10-20, 20-32 and 32-40 minutes after 11C-methionine injection, compared with that at 45-60 minutes, was 96±23%, 91±8.6%, 94±6.9% and 96±6.9%, respectively. A correlation study between the TMR and the DAR demonstrated good results in both the normal tissue (r=0.96) and the tumorous lesions (r=0.93). In conclusion, the 11C-methionine uptake can be evaluated at any time from 10 minutes after the injection of 11C-methionine and both the TMR and the DAR are considered to be useful methods for evaluating 11C-methionine uptake using positron emission tomography. (author)

  15. Development and validation of an UPLC-MS/MS method for the quantification of ethoxzolamide in blood, brain tissue, and bioequivalent buffers: applications to absorption, brain distribution, and pharmacokinetic studies.

    Gao, Song; Zhao, Jing; Yin, Taijun; Ma, Yong; Xu, Beibei; Moore, Anthony N; Dash, Pramod K; Hu, Ming

    2015-04-01

    The purpose of this study is to develop and validate an UPLC-MS/MS method to quantify ethoxzolamide in plasma (EZ) and apply the method to absorption, brain distribution, as well as pharmacokinetic studies. A C₁₈ column was used with 0.1% of formic acid in acetonitrile and 0.1% of formic acid in water as the mobile phases to resolve EZ. The mass analysis was performed in a triple quadrupole mass spectrometer using multiple reaction monitoring (MRM) with positive scan mode. The results show that the linear range of EZ is 4.88-10,000.00 nM. The intra-day variance is less than 12.43% and the accuracy is between 88.88 and 108.00%. The inter-day variance is less than 12.87% and accuracy is between 89.27 and 115.89%. Protein precipitation was performed using methanol to extract EZ from plasma and brain tissues. Only 40 μL of plasma is needed for analysis due to the high sensitivity of this method, which could be completed in less than three minutes. This method was used to study the pharmacokinetics of EZ in SD rats, and the transport of EZ in Caco-2 and MDCK-MDR1 overexpressing cell culture models. Our data show that EZ is not a substrate for p-glycoprotein (P-gp) and its entry into the brain may not limited by the blood-brain barrier. PMID:25706567

  16. Nutrition and magnesium absorption.

    Brink, E.J.

    1992-01-01

    The influence of various nutrients present in dairy products and soybean-based products on absorption of magnesium has been investigated. The studies demonstrate that soybean protein versus casein lowers apparent magnesium absorption in rats through its phytate component. However, true magnesium absorption was neither affected by soybean protein in the diet nor by supplemental phytate. The inhibitory influence of soybean protein and phytate on apparent magnesium absorption was found to be cau...

  17. Pharmacokinetics, tissue distribution and mass balance of radiolabeled dihydroartemisinin in male rats

    Weina Peter J

    2009-05-01

    Full Text Available Abstract Background Dihydroartemisinin (DHA, a powerful anti-malarial drug, has been used as monotherapy and artemisinin-based combination therapy (ACT for more than decades. So far, however, the tissue distribution and metabolic profile of DHA data are not available from animal and humans. Methods Pharmacokinetics, tissue distribution, mass balance, and elimination of [14C] DHA have been studieded in rats following a single intravenous administration. Protein binding was performed with rat and human plasma. Drug concentrations were obtained up to 192 hr from measurements of total radioactivity and drug concentration to determine the contribution by the parent and metabolites to the total dose of drug injected from whole blood, plasma, urine and faecal samples. Results Drug was widely distributed after 1 hr and rapidly declined at 24 hr in all tissues except spleen until 96 hrs. Only 0.81% of the total radioactivity was detected in rat brain tissue. DHA revealed a high binding capacity with both rat and human plasma proteins (76–82%. The concentration of total radioactivity in the plasma fraction was less than 25% of that in blood total. Metabolism of DHA was observed with high excretion via bile into intestines and approximately 89–95% dose of all conjugations were accounted for in blood, urine and faeces. However, the majority of elimination of [14C] DHA was through urinary excretion (52% dose. The mean terminal half-lives of plasma and blood radioactivity (75.57–122.13 h were significantly prolonged compared with that of unchanged DHA (1.03 h. Conclusion In rat brain, the total concentration of [14C] was 2-fold higher than that in plasma, indicating the radioactivity could easily penetrate the brain-blood barrier. Total radioactivity distributed in RBC was about three- to four-fold higher than that in plasma, suggesting that the powerful anti-malarial potency of DHA in the treatment of blood stage malaria may relate to the high RBC

  18. Effects of perindopril on expression of kidney aquaporin-2 and urine aquaporin-2 excretion in chronic heart failure rats

    欧阳邵

    2013-01-01

    Objective To determine the expression of kidneyaquaporin-2(AQP2) and urine AQP2 excretion in chronic heart failure(CHF) rats and investigate effects of perindopril on the expression and excretion of AQP2.Methods

  19. Formulation of Relationships between the Radiation Exposure of Tissues and the Excretion Rate of Nuclides

    The organization of protection against undue occupational exposure to internal radiation involves several processes: 1 1. Decisions as to the highest dose-rates, for the body or for particular organs-, that can be regarded as permissible; 2. Estimation, for all relevant nuclides, of the intakes, and of the body burdens, which would cause any such dose-rates to be reached or sustained; 3. Monitoring of exposed individuals to determine what fraction of a permissible body burden of any nuclide is retained in the body. Techniques of monitoring by whole-body counting, or by data on excretion or exhalation rates, are relevant to the Symposium. Several major problems are involved: (a) For most radionuclides, insufficient metabolic data are available to link tissue dose-rates either with body burdens or with excretion rates, at least as based on adequately large numbers of normal human subjects; (b) The large variability between different subjects in physiological functions, such as excretion or clearance rates, limits severely the inferences that can be made from isolated human observations, and restricts also the deductions as to body burden that can be drawn from the excretion rates observed in any individual; (c) The complex variation of excretion rate with time after a single intake cf many, nuclides prevents any direct deduction of body burden from excretion rate when the time course of intake is unknown, except in the special case of a nuclide which is excreted at a rate which decreases (mono-) exponentially with time since intake; (d) In particular, many radionuclides which are of particular importance because they are highly concentrated and long retained in certain organs, may show initial rapid excretion of the fraction of intake which is not so concentrated, and much slower and more prolonged excretion of the retained part. A small recent intake will thus contribute preponderating to the excretion as compared with that from a much larger and more important

  20. Evaluation of the impact of alveolar nitrogen excretion on indices derived from multiple breath nitrogen washout.

    Niklas Nielsen

    Full Text Available BACKGROUND: A large body of evidence has now accumulated describing the advantages of multiple breath washout tests over conventional spirometry in cystic fibrosis (CF. Although the majority of studies have used exogenous sulphur hexafluoride (SF6 as the tracer gas this has also led to an increased interest in nitrogen washout tests, despite the differences between these methods. The impact of body nitrogen excreted across the alveoli has previously been ignored. METHODS: A two-compartment lung model was developed that included ventilation heterogeneity and dead space (DS effects, but also incorporated experimental data on nitrogen excretion. The model was used to assess the impact of nitrogen excretion on washout progress and accuracy of functional residual capacity (FRC and lung clearance index (LCI measurements. RESULTS: Excreted nitrogen had a small effect on accuracy of FRC (1.8% in the healthy adult model. The error in LCI calculated with true FRC was greater (6.3%, and excreted nitrogen contributed 21% of the total nitrogen concentration at the end of the washout. Increasing DS and ventilation heterogeneity both caused further increase in measurement error. LCI was increased by 6-13% in a CF child model, and excreted nitrogen increased the end of washout nitrogen concentration by 24-49%. CONCLUSIONS: Excreted nitrogen appears to have complex but clinically significant effects on washout progress, particularly in the presence of abnormal gas mixing. This may explain much of the previously described differences in washout outcomes between SF6 and nitrogen.

  1. Urinary dopamine in man and rat: effects of inorganic salts on dopamine excretion.

    Ball, S G; Oats, N S; Lee, M R

    1978-08-01

    1. Plasma and urine free dopamine (3,4-dihydroxyphenethylamine) were measured in six normal male volunteer subjects and the urinary clearance of dopamine was calculated for each subject. 2. The excretion rates for free dopamine in man were greater than could be explained by simple renal clearance. It was concluded that free dopamine must, therefore, be formed in the kidney. 3. Changes in urinary dopamine excretion were studied in four groups of rats initially maintained on low sodium diet and then given equimolar dietary supplements of NaCl, NaHCO3, KCl or NH4Cl, to study the specificity of the previously observed increase in dopamine excretion after increased dietary NaCl. 4. The mean dopamine excretion increased significantly in rats given NaCl, KCl and NH4Cl, whereas dopamine excretion decreased in those given NaHCO3. 5. The failure of dopamine excretion to rise in response to loading with NaHCO3 was unexpected, and argues against a simple effect of volume expansion by the sodium ion. The increase in dopamine excretion with KCl and NH4Cl showed that this response was not specific to the sodium ion. PMID:28196

  2. High-fiber rye diet increases ileal excretion of energy and macronutrients compared with low-fiber wheat diet independent of meal frequency in ileostomy subjects

    Isaksson, Hanna; Landberg, Rikard; Sundberg, Birgitta;

    2013-01-01

    Background:Whole-grain foods and cereal dietary fiber intake is associated with lower body weight. This may partly result from lower energy utilization of high-fiber diets. Objective: In the present study, the impact on ileal excretion of energy and macronutrients in response to a rye bread high-...... independent of meal frequency. This suggests that a high intake of rye may result in lower availability of macronutrients for small intestinal digestion and absorption. A regular intake of rye may therefore have implications for weight management.......-fiber diet compared to a refined wheat low-fiber diet was investigated. Furthermore, the effect of meal frequency on apparent absorption of nutrients was studied for the first time. Design: Ten participants that had undergone ileostomy consumed standardized iso-caloric diets, including low-fiber wheat bread...

  3. Calcium absorption and achlorhydria

    Defective absorption of calcium has been thought to exist in patients with achlorhydria. The author compared absorption of calcium in its carbonate form with that in a pH-adjusted citrate form in a group of 11 fasting patients with achlorhydria and in 9 fasting normal subjects. Fractional calcium absorption was measured by a modified double-isotope procedure with 0.25 g of calcium used as the carrier. Mean calcium absorption (+/- S.D.) in the patients with achlorhydria was 0.452 +/- 0.125 for citrate and 0.042 +/- 0.021 for carbonate (P less than 0.0001). Fractional calcium absorption in the normal subjects was 0.243 +/- 0.049 for citrate and 0.225 +/- 0.108 for carbonate (not significant). Absorption of calcium from carbonate in patients with achlorhydria was significantly lower than in the normal subjects and was lower than absorption from citrate in either group; absorption from citrate in those with achlorhydria was significantly higher than in the normal subjects, as well as higher than absorption from carbonate in either group. Administration of calcium carbonate as part of a normal breakfast resulted in completely normal absorption in the achlorhydric subjects. These results indicate that calcium absorption from carbonate is impaired in achlorhydria under fasting conditions. Since achlorhydria is common in older persons, calcium carbonate may not be the ideal dietary supplement

  4. EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA); Scientific Opinion on the substantiation of a health claim related to beta-palmitate and increased calcium absorption pursuant to Article 14 of Regulation (EC) No 1924/2006

    Tetens, Inge

    triglycerides may increase calcium absorption by decreasing faecal calcium excretion as calcium soaps, albeit a significant effect on calcium absorption was demonstrated in one study only. The Panel concludes that the evidence provided is insufficient to establish a cause and effect relationship between the...

  5. High-fiber rye diet increases ileal excretion of energy and macronutrients compared with low-fiber wheat diet independent of meal frequency in ileostomy subjects

    Hanna Isaksson

    2013-12-01

    Full Text Available Background: Whole-grain foods and cereal dietary fiber intake is associated with lower body weight. This may partly result from lower energy utilization of high-fiber diets. Objective: In the present study, the impact on ileal excretion of energy and macronutrients in response to a rye bread high-fiber diet compared to a refined wheat low-fiber diet was investigated. Furthermore, the effect of meal frequency on apparent absorption of nutrients was studied for the first time. Design: Ten participants that had undergone ileostomy consumed standardized iso-caloric diets, including low-fiber wheat bread (20 g dietary fiber per day for 2 weeks followed by high-fiber rye bread (52 g dietary fiber per day for 2 weeks. The diets were consumed in an ordinary (three meals per day and a nibbling (seven meals per day meal frequency in a cross-over design. Ileal effluents were collected during 24 h at the third day of each of the four dietary periods and analyzed for gross energy and nutrient contents. Results: The results showed that intake of rye bread high-fiber diet compared to the refined wheat low-fiber diet caused an increase in ileal excretion of energy and macronutrients. The effect was independent of meal frequency. This suggests that a high intake of rye may result in lower availability of macronutrients for small intestinal digestion and absorption. A regular intake of rye may therefore have implications for weight management.

  6. Systematic review focusing on the excretion and protection roles of sweat in the skin.

    Peng, Yan; Cui, Xiao; Liu, Yanhua; Li, Yaoyin; Liu, Jian; Cheng, Biao

    2014-01-01

    The skin excretes substances primarily through sweat glands. Several conditions have been demonstrated to be associated with diminished sweating. However, few studies have concentrated on the metabolism and excretion of sweat. This review focuses on the relationship between temperature and the thermoregulatory efficacy of sweat, and then discusses the excretion of sweat, which includes the metabolism of water, minerals, proteins, vitamins as well as toxic substances. The potential role of sweat secretion in hormone homeostasis and the effects on the defense system of the skin are also clarified. PMID:24577280

  7. QSO Absorption Lines from QSOs

    Bowen, D V; Ménard, B; Chelouche, D; Inada, N; Oguri, M; Richards, G T; Strauss, M A; Vanden Berk, Daniel E; York, D G; Bowen, David V.; Hennawi, Joseph F.; Menard, Brice; Chelouche, Doron; Inada, Naohisa; Oguri, Masamune; Richards, Gordon T.; Strauss, Michael A.; Berk, Daniel E. Vanden; York, Donald G.

    2006-01-01

    We present the results of a search for metal absorption lines in the spectra of background QSOs whose sightlines pass close to foreground QSOs. We detect MgII(2796,2803) absorption in Sloan Digital Sky Survey (SDSS) spectra of four z>1.5 QSOs whose lines of sight pass within 26-98 kpc of lower redshift (z~0.5-1.5) QSOs. The 100% [4/4 pairs] detection of MgII in the background QSOs is clearly at odds with the incidence of associated (z_abs ~ z_em) systems -- absorbers which exist towards only a few percent of QSOs. Although the quality of our foreground QSO spectra is not as high as the SDSS data, absorption seen towards one of the background QSOs clearly does not show up at the same strength in the spectrum of the corresponding foreground QSO. This implies that the absorbing gas is distributed inhomogeneously around the QSO, presumably as a direct consequence of the anisotropic emission from the central AGN. We discuss possible origins for the MgII lines, including: absorption by gas from the foreground QSO h...

  8. The HI absorption "Zoo"

    Geréb, K.; Maccagni, F. M.; Morganti, R.; Oosterloo, T. A.

    2015-03-01

    We present an analysis of the H I 21 cm absorption in a sample of 101 flux-selected radio AGN (S1.4 GHz> 50 mJy) observed with the Westerbork Synthesis Radio Telescope (WSRT). We detect H I absorption in 32 objects (30% of the sample). In a previous paper, we performed a spectral stacking analysis on the radio sources, while here we characterize the absorption spectra of the individual detections using the recently presented busy function. The H I absorption spectra show a broad variety of widths, shapes, and kinematical properties. The full width half maximum (FWHM) of the busy function fits of the detected H I lines lies in the range 32 km s-1 200 km s-1). We study the kinematical and radio source properties of each group, with the goal of identifying different morphological structures of H I. Narrow lines mostly lie at the systemic velocity and are likely produced by regularly rotating H I disks or gas clouds. More H I disks can be present among galaxies with lines of intermediate widths; however, the H I in these sources is more unsettled. We study the asymmetry parameter and blueshift/redshift distribution of the lines as a function of their width. We find a trend for which narrow profiles are also symmetric, while broad lines are the most asymmetric. Among the broadest lines, more lines appear blueshifted than redshifted, similarly to what was found by previous studies. Interestingly, symmetric broad lines are absent from the sample. We argue that if a profile is broad, it is also asymmetric and shifted relative to the systemic velocity because it is tracing unsettled H I gas. In particular, besides three of the broadest (up to FW20 = 825 km s-1) detections, which are associated with gas-rich mergers, we find three new cases of profiles with blueshifted broad wings (with FW20 ≳ 500 km s-1) in high radio power AGN. These detections are good candidates for being HI outflows. Together with the known cases of outflows already included in the sample (3C 293 and

  9. {sup 14}C-Methylenebisphenylisocyanate ({sup 14}C-MDI). Study of absorption after single dermal and intradermal administration in rats

    Leibold, E.; Hoffmann, H.D.; Hildebrand, B

    1999-07-01

    The absorption, distribution and excretion of radioactivity was studied in groups of four male Wistar rats following a single dermal and intradermal administration of {sup 14}C- Methylenebisphenylisocyanate ({sup 14}C-MDI) at nominal dose levels of 4.0 and 0.4 mg/cm{sup 2} for dermal administration and 0.4 mg/animal for intradermal administration. These dose levels nominally corresponded to 40 and 4.0 mg/animal for dermal administration. Considering the animal weights, dose levels corresponded to about 140 and 14 mg/kg body weight (dermal administration) and 1.4 mg/kg body weight (intradermal administration). In the experiments with dermal administration, animals were exposed for 8 hours and sacrificed 8, 24 or 120 h after beginning of exposure. In the experiment with intradermal administration, animals were sacrificed 120 h after treatment. After dermal administration of {sup 14}C-MDI, mean recoveries of radioactivity from all dose groups were in the range from 97.86 to 108.07% of the total radioactivity administered. Generally, the largest proportion of radioactivity was found at the application site and dressing. The total amount of radioactivity absorbed (including excreta, cage wash, tissues/organs and carcass) increased with increasing sacrifice time. Dermal absorption was very low and quantitatively similar at both dose levels; maximally ca. 0.9 % of the applied radioactivity was absorbed. After intradermal administration of {sup 14}C-MDI, the mean recovery of radioactivity was 100.90 % of the radioactivity administered. The largest proportion of radioactivity was found at the application site. The total amount of radioactivity absorbed (including excreta, cage wash, tissues/organs and carcass) amounted to about 26 % of the radioactivity applied. Irrespective of the mode of administration of 1{sup 4C}-MDI, concentrations of radioactivity in tissues and organs generally were below 1 {mu}g Eq/g at 120 h after administration. In summary, the results of this

  10. Ten element contents and their distribution in fruits determinated by atomic absorption spectrometry%原子吸收光谱法测定水果中10种元素含量及分布

    蔡艳荣; 刘媛; 李玲玲; 王伟

    2011-01-01

    Objective To investigate the contents and distributions of the Zn, Cu, K, Ca, Mg, Mn, Pb, Cd, Cr and Se elements in the fruits. Methods The fruit samples were digested with wet method. Contents of zinc, copper,calcium,magnesium,potassium and manganese were determined by flame atomic absorption spectrometry (FAAS).Contents of lead, cadmium, chromium and selenium were determined by graphite furnace atomic absorption spectrometry( GFAAS). Results There existed differences for the element distribution in each part of the fruits. The contents of lead in the grapes, dried jujubes and papaya were close to the pollutant concentration limits, but their contents were lower than standard limits. The contents of chromium in the Guoguang apples, pears, dry jujubes and cherry tomatoes were higher than standard limits. Selenium was detected in the Guoguang apples, bananas, pears, dry jujubes, papaya and pomelo. The contents of copper in the grapes and dry jujubes exceeded standard limits. The contents of zinc were lower than standard limits. The calcium contents were the highest in the papaya. The contents of magnesium and manganese were the highest in the dry jujubes. The contents of potassium were higher in the dry jujubes,pomelo and cherry tomato. Conclusion The highest levels of the elements were in the seeds, and the second levels were in the skin ,the lowest levels were in the pulp. The element contents of the peel were higher than those the pulp.%目的 调查水果中锌、铜、钾、钙、镁、锰、铅、镉、铬和硒10种元素含量分布情况.方法 采用湿法消解水果样品,火焰原子吸收光谱法检测水果中的锌、铜、钾、钙、镁和锰的含量,石墨炉原子吸收光谱法检测铅、镉、铬和硒的含量.结果 10种元素在水果中各部位的分布有比较大的差异.葡萄、干枣和木瓜中铅含量接近于污染物浓度限量,但没有超过标准.国光苹果、梨、干枣和圣女果中铬的含量都超标.国光苹

  11. 不同盐度胁迫对芦荟生长和离子吸收分配的影响%Effects of Salt Concentration on Growth, Ion Absorption and Distribution of Aloe vera L.

    马艳萍

    2012-01-01

    为探索芦荟对微咸水灌溉栽培的适应性,研究不同盐浓度对其生长和离子吸收分配的影响.结果表明,长期(120天)以含盐溶液灌溉栽培,盐浓度达200 mmol/L NaCl显著抑制芦荟生长,100 mmol/LNaCl对芦荟生长的抑制作用显著减轻,50 mmol/L NaCl不抑制芦荟生长.同时,以50 mmol/L NaCl溶液灌溉对芦荟盐分离子吸收分配影响轻微,但盐浓度达100 mmol/LNaCl对芦荟影响显著:根、茎、叶中K+含量显著下降,Na+、Cl-含量显著增大,K+/Na+大幅减小.X-射线能谱分析结果进一步表明,叶片贮水组织是芦荟积累盐分离子的重要部位,但100 mmol/L NaCl胁迫下芦荟根尖和叶片细胞中的离子平衡受到显著干扰.结果说明,芦荟适于用微咸水灌溉栽培,叶片贮水组织在缓解其盐胁迫中可起重要作用.%To explore the adaptability of irrigating aloe with weakly brine water, the effects of different concentration salinity stresses on growth, ion absorption and distribution of aloe plants were investigated.Experimental results showed that irrigation with 200 mmol/L NaCl for 120 d significantly retarded aloe growth, but the negative effects of irrigating aloe with 100 mmol/L NaCl on aloe growth were significantly relieved, even irrigating with 50 mmol/L NaCl did not retard aloe growth.The effects of irrigating with 50 mmol/L NaCl on ion absorption, transportation and distribution of aloe plants were not significant, but irrigating with 100 mmol/L NaCl were significant: K + contents of root, stem and leaf significantly decreased, Na + and Cl- content significantly increased, K+Na+ ratio significantly decreased.X-ray microanalysis results further showed that leaf aqueous was a main part of accumulating salt ion but ion homeostasis in root and leaf cells of aloe plants were significantly interrupted under 100 mmol/L NaCl stress.The experiment results suggested that Aloe vera L.was suitable to be irrigated with weakly brine water, and leaf

  12. Variability of calcium absorption

    Variability in calcium absorption was estimated in three groups of normal subjects in whom Ca absorption was measured by standard isotopic-tracer methods at interstudy intervals ranging from 1 to 4 mo. Fifty absorption tests were performed in 22 subjects. Each was done in the morning after an overnight fast with an identical standard breakfast containing a Ca load of approximately 250 mg. Individual fractional absorption values were normalized to permit pooling of the data. The coefficient of variation (CVs) for absorption for the three groups ranged from 10.57 to 12.79% with the size of the CV increasing with interstudy duration. One other published study presenting replicate absorption values was analyzed in a similar fashion and was found to have a CV of absorption of 9.78%. From these data we estimate that when the standard double-isotope method is used to measure Ca absorption there is approximately 10% variability around any given absorption value within an individual human subject and that roughly two-thirds of this represents real biological variability in absorption

  13. L-Malate’s Plasma and Excretion Profile in the Treatment of Moderate and Severe Hemorrhagic Shock in Rats

    Indra N. Waack

    2016-01-01

    Full Text Available Introduction. Malate is a standard component in fluid therapy within a wide range of medical applications. To date, there are insufficient data regarding its plasma distribution, renal excretion, and metabolism after infusion. This study aimed to investigate these three aspects in a rat model of moderate and severe hemorrhagic shock (HS. Methods. Male Wistar rats were subjected to HS by dropping the mean arterial blood pressure to 25–30 mmHg (severe and 40–45 mmHg (moderate, respectively, for 60 minutes. Subsequently, reperfusion with Ringer-saline or a malate containing crystalloid solution (7 mM, 13.6 mM, and 21 mM, resp. was performed within 30 minutes, followed by an observation period of 150 minutes. Results. In the present experiments, malate rapidly disappeared from the blood, while only 5% of the infused malate was renally excreted. In the resuscitation interval the urinary citrate and succinate amounts significantly increased compared to control. Conclusion. Malate’s half-life is between 30 and 60 minutes in both, moderate and severe HS. Thus, even under traumatic conditions malate seems to be subjected to rapid metabolism with participation of the kidneys.

  14. Development of an algorithm to evaluate plutonium metabolic model for systemic retention and excretion

    Liver biliary secretion influences the plutonium (pu) content of feces. A mammillary model that incorporates the enterohepatic circulation is developed for the purpose of improving internal dose assessment amd bioassay models. This model uses a whole body uptake retention function to obtain the distribution of Pu in the body and the rates of elimination of Pu in urine and feces simultaneously. The development of the model relies on the fact that a retention function expressed by a sum of exponential terms can be depicted by a mammillary model involving the translocation of a contaminant between a central and various peripheral compartments. In this study, an algorithm is developed to compute the translocation rate constants that are consistent with the systemic retention function. The thesis provides a method that can be used to confirm and improve Pu metabolic models. This method can be extended to other elements and used to make estimates of intakes and internal radiation doses from excretion bioassay data. 70 refs., 18 figs., 12 tabs

  15. Faecal and urinary excretion of 14C-steroids in ponies

    Over a period of 4 hours the following 14C-steroid hormones (3.7 MBq = 0.1 mCi) dissolved in 0.9 % NaCl/10 % ethanol were infused i.v. in mature ponies: progesterone (3 mares), testosterone (3 stallions) oestrone and cortisol (both in 2 mares and 2 stallions). Faeces were collected immediately after defecation. In mares the urine was sampled via permanent catheters and in stallions immediately after voiding. In addition blood samples were taken from the jugular vein. The radioactivity of urine and plasma (n =470 and 194, respectively) was determined directly and that of faecal samples (n =450) after extraction or oxidation by liquid scintillation counting. The distribution of radioactivity within the faecal balls was investigated too (n = 627). In urine the maximum of radioactivity was observed during or immediately after the infusion period, whereas in faeces it was found 17 to 30 hours later. Afterwards the radioactivity declined and within 2 weeks it was below the detection limit of the method. A total of 90±11 % of the administered radioactivity was recovered, more than 90 % of it within 2.5 days after infusion. After application of progesterone, cortisol, testosterone and oestrone, 74±5, 41±5, 28±7 and 2±1 % of the recovered radioactivity were found in the faeces, whereas the remaining portions were excreted via urine. Higher concentrations of radioactivity were found in the outer layers of the faecal balls, than in the inner ones. (author)

  16. Development of a physiologically-based computational kidney model to describe the renal excretion of hydrophilic agents in rats

    Christoph eNiederalt

    2013-01-01

    Full Text Available A physiologically-based kidney model was developed to analyze the renal excretion and kidney exposure of hydrophilic agents, in particular contrast media, in rats. In order to study the influence of osmolality and viscosity changes, the model mechanistically represents urine concentration by water re-absorption in different segments of kidney tubules and viscosity dependent tubular fluid flow.The model was established using experimental data on the physiological steady state without administration of any contrast media or drugs. These data included the sodium and urea concentration gradient along the cortico-medullary axis, water reabsorption, urine flow and sodium as well as urea urine concentrations for a normal hydration state. The model was evaluated by predicting the effects of mannitol and contrast media administration and comparing to experimental data on cortico-medullary concentration gradients, urine flow, urine viscosity, hydrostatic tubular pressures and single nephron glomerular filtration rate. Finally the model was used to analyze and compare typical examples of ionic and non-ionic monomeric as well as non-ionic dimeric contrast media with respect to their osmolality and viscosity. With the computational kidney model, urine flow depended mainly on osmolality, while osmolality and viscosity were important determinants for tubular hydrostatic pressure and kidney exposure. The low diuretic effect of dimeric contrast media in combination with their high intrinsic viscosity resulted in a high viscosity within the tubular fluid. In comparison to monomeric contrast media, this led to a higher increase in tubular pressure, to a reduction in glomerular filtration rate and tubular flow and to an increase in kidney exposure.The presented kidney model can be implemented into whole body physiologically-based pharmacokinetic models and extended in order to simulate the renal excretion of lipophilic drugs which may also undergo active secretion

  17. Efficacy of a novel chitosan formulation on fecal fat excretion: a double-blind, crossover, placebo-controlled study.

    Barroso Aranda, Jorge; Contreras, Francisco; Bagchi, Debasis; Preuss, Harry G

    2002-01-01

    The ability of a novel chitosan formulation to influence gastrointestinal fat absorption in vivo was examined in a double-blind, placebo-controlled, crossover study by determining the content of total fat in feces in two groups of subjects. Twenty-nine normal healthy subjects were recruited for the study. Twenty-four participants completed the test period with the chitosan formulation, and 21 completed the placebo phase of study. During the placebo and the test periods, the subjects were administered six capsules three times daily 10 minutes before meals for three days and for the two days of the stool collection. A daily serving of six tablets of the test compound contained 2100 mg chitosan and 300 mg psyllium husk seeds. In respect to the baseline period, the test compound increased fat excretion significantly whether the test period preceded or proceeded the placebo period (ppsyllium husk seeds [+3.63 gm/day +/- 0.83 (SEM) vs. -0.15 gm/day +/- 0.94 (SEM) (p=0.004)]. The average daily increase in fecal fat of 3-4 grams over control could account for a decrease in calorie consumption of 30-40 kcal per day. A total of 19 subjects completed both parts of the study. Examining the data from these 19 subjects by ANOVA, it was found that the period when the test compounds were given was statistically significantly different from the placebo baseline, placebo experimental, and test baseline periods. Using multiple comparisons, it was ascertained that the novel formulation containing chitosan plus psyllium husk seeds increases fecal fat excretion. PMID:12939120

  18. Hyperthyroidism alters excretion of dichloroethylene metabolites into serum and bile

    Hepatotoxicity of 1,1-dichloroethylene (DCE) is enhanced in rats made hyperthyroid by excessive thryoxine (T4). Our objective was to determine if the enhancement of DCE injury by T4 was associated with alterations in the biologic fate of DCE, especially clearance of DCE metabolites into bile. Male SD rats (275 g) were injected with T4 (40μg/100 g) 3 times at 48 hr intervals (hyperthyroid, HyperT) or sham injected (euthyroid, EuT). A 8 AM, all rats had jugular and biliary cannulas positioned under pentobarbital anesthesia. At 9:30 AM, all rats received 14C-DCE (100 mg/kg) po in mineral oil. 14C-DCE metabolite levels were measured serially in blood and bile for 4 hr and in liver at 4 hr. Major observations were: Rate of biliary excretion of 14C by EuT was stable from 0.5 to 4 hr, while biliary 14C in HyperT peaked at 1 hr at a level about 100% greater then EuT but then gradually declined by 4 hr to about 50% less than EuT. Serum 14C was also stable from 2 to 4 hr in EuT, while serum 14C in HyperT continued to rise and at 4 hr, was twice that of EuT. At 4 hr, HyperT had two times more 14C covalently bound to total liver and liver mitochondria than EuT. Thus, enhancement of DCE injury by hyperthyroidism was associated with a temporal shift in DCE metabolite clearance from bile to blood and with more covalent binding of toxin to liver

  19. Metabolic excretion and retention patterns of incorporated radionuclides in reference man

    The paper gives formulae for calculating the total expected 50-year dose (TED50) and excretion rate for four patterns of uptake as well as numerical descriptions of the ICRP ''gut model'' and ''lung model''. (author)

  20. Effect of iron poly (sorbitolgluconic acid) complex on urinary cellular excretion.

    Elliott, H L; Lawrence, J R; Campbell, B C; Goldberg, A; Smart, L E

    1981-01-01

    The intramuscular injection of 250 mg iron poly (sorbitol-gluconic acid) complex caused no increase in urinary cellular or bacterial excretion in 8 patients with chronic pyelonephritis, 4 patients with non-infective renal disease, and 4 controls. However, in 4 patients with chronic infective disease of the renal tract given 500 g there was a significant increase in cellular excretion. This response was not seen in 2 control patients, nor in 2 patients with non-infective renal disease. Using a differential staining technique, this increase in urinary cellular excretion was found to be due, not to leucocytes, but to renal tubular cells. The precise significance of this is unclear, but there would be concern that the high concentration of excreted iron was providing a 'toxic' insult to susceptible, infection-damaged cells. PMID:7226874

  1. Dependency of renal thorium and uranium excretion from age and gender in non-exposed persons

    For the assessment of an occupational incorporation of thorium or uranium it is essential to know which portion of the measured activity is caused by natural sources. In the present study the daily urinary excretion of 232Th and 238U was measured in 76 healthy volunteers. None of them had a previous history of occupational exposure to thorium or uranium. The data show no difference in the excretion between male and female subjects. Whereas in adolescents only little excretion of 232Th and 238U is found, a significantly increasing variation of thorium and uranium in urine is observed with progressing age. From the data obtained an age-related upper limit of 232Th and 238U urinary excretion can be derived, which may be useful for the interpretation of a measured value due to the occupational exposure. (orig.)

  2. Splanchnic and peripheral release of 3-methylhistidine in relation to its urinary excretion in human infection

    Sjölin, J; Stjernström, H; Henneberg, S; Andersson, E; Mårtensson, J; Friman, G; Larsson, J

    1989-01-01

    The present investigation was undertaken in order to determine the release of 3-methylhistidine (3MH) from the splanchnic region and from the leg, and the contributions these make to the increase in urinary 3MH excretion in infection. Thirteen febrile patients with infection were investigated...... concluded that skeletal muscle is the source, and these results thus validate the use of urinary 3MH excretion as a marker of myofibrillar protein catabolism in infected patients....... from the splanchnic region 0.012 +/- 0.013 mumol/min. These releases of 3MH constitute 27% +/- 2% and 8% +/- 6% of the individual urinary excretions, respectively. With increasing degree of catabolism, measured as individual 3MH increase above baseline excretion or as the 3MH to creatinine ratio (3MH...

  3. Evidence that auxin-induced growth of soybean hypocotyls involves proton excretion

    Rayle, D.L. (San Diego State Univ., CA); Cleland, R.E.

    1980-09-01

    The role of H/sup +/ excretion in auxin-induced growth of soybean hypocotyl tissues has been investigated, using tissues whose cuticle was rendered permeable to protons or buffers by scarification (scrubbing). Indoleacetic acid induces both elongation and H/sup +/ excretion after a lag of 10 to 12 minutes. Cycloheximide inhibits growth and causes the tissues to remove protons from the medium. Neutral buffers (pH 7.0) inhibit auxin-induced growth of scrubbed but not intact sections; the inhibition increases as the buffers strength is increased. Both live and frozen-thawed sections, in the absence of auxin, extend in response to exogenously supplied protons. Fusicoccin induces both elongation and H/sup +/ excretion at rates greater than does auxin. These results indicate that H/sup +/ excretion is involved in the initiation of auxin-induced elongation in soybean hypocotyl tissue.

  4. Relationship Between Serum Adiponectin and Urinary Albumin Excretion Rate in Patients with Diabetes Nephropathy

    To explore the relationship between the levels of serum adiponectin and urinary albumin excretion rate in patients with type 2 diabetes nephropathy, the serum levels of adiponectin and the levels of urinary albumin excretion rate in diabetes patients before and after treatment with pioglitazone were tested by ELISA and automatic biochemical analyzer respectively. The results showed that the serum levels of adiponectin in DM and DN group were lower than that of normal controls(P<0.01), but they gradually increased with progression (P<0.01). The serum adiponectin level was positively correlated with urinary albumin excretion rate (r= 0.284, P<0.05). The urinary albumin level decreased (P<0.01) and the serum levels of adiponectin increased after treatment with pioglitazone in DN group. The serum levels of adiponectin and urinary albumin excretion rate may play important role in the indication of treatment of diabetes. (authors)

  5. Renal kallikrein excretion and epigenetics in human acute kidney injury: Expression, mechanisms and consequences

    Tolwani Ashita

    2011-06-01

    Full Text Available Abstract Background Renal kallikrein (KLK1 synthesis and urinary excretion are reportedly diminished during AKI (acute kidney injury in animal models, and provision of kallikrein abrogates renal injury in this setting, but data in human AKI is limited. Therefore we first examined KLK1 renal excretion in human AKI, and then probed potential endocrine and epigenetic mechanisms for its alterations. Methods KLK1 enzymatic activity excretion was evaluated in urine from patients with established or incipient AKI, versus healthy/non-hospital as well as ICU controls. Endocrine control of KLK1 excretion was then probed by catecholamine and aldosterone measurements in established AKI versus healthy controls. To examine epigenetic control of KLK1 synthesis, we tested blood and urine DNA for changes in promoter CpG methylation of the KLK1 gene, as well as LINE-1 elements, by bisulfite sequencing. Results Patients with early/incipient AKI displayed a modest reduction of KLK1 excretion, but unexpectedly, established AKI displayed substantially elevated urine KLK1 excretion, ~11-fold higher than healthy controls, and ~3-fold greater than ICU controls. We then probed potential mechanisms of the change. Established AKI patients had lower SBP, higher heart rate, and higher epinephrine excretion than healthy controls, though aldosterone excretion was not different. Promoter KLK1 CpG methylation was higher in blood than urine DNA, while KLK1 methylation in blood DNA was significantly higher in established AKI than healthy controls, though KLK1 methylation in urine tended to be higher in AKI, directionally consistent with earlier/incipient but not later/established changes in KLK1 excretion in AKI. On multivariate ANOVA, AKI displayed coordinate changes in KLK1 excretion and promoter methylation, though directionally opposite to expectation. Control (LINE-1 repetitive element methylation in blood and urine DNA was similar between AKI and controls. Conclusions

  6. Identification of factors associated with increased excretion of foot-and-mouth disease virus

    Bravo De Rueda, C.; Dekker, A.; Eble, P. L.; Jong, de, J.

    2014-01-01

    We investigated which variables possibly influence the amount of foot-and-mouth disease virus (FMDV) shed in secretions and excretions by FMDV infected animals, as it is likely that the amount of FMDV shed is related to transmission risk. First, in a separate analysis of laboratory data, we showed that the total amount of FMDV in secretions and excretions from infected animals is highly correlated with maximum titres of FMDV. Next, we collected data from 32 published scientific articles in wh...

  7. Total Fluoride Intake and Urinary Excretion in German Children Aged 3–6 Years

    Haftenberger, Marjolein; Viergutz, Gabriele; Neumeister, Volker; Hetzer, Gisela

    2014-01-01

    There have only been few investigations comparing total fluoride intake and the fluoride proportion excreted in urine in pre–school children. In addition, the results of available studies are conflicting. Total fluoride intake was assessed in 11 healthy children aged 3–6 years on 2 consecutive days and urinary fluoride excretion was determined. The duplicate–diet approach was used for the assessment of fluoride intake from solid and liquid foods. Fluoride intake from toothbrushing was calcula...

  8. The effect of phototherapy on urinary calcium excretion in term neonates

    Afshin Safaei Asl; Marjaneh Zarkeshl; Abtin Heidarzadeh; Shohreh Maleknejad; Kaveh Hagikhani

    2016-01-01

    Phototherapy is the most common, most effective, and least dangerous treatment method for neonatal hyperbilirubinemia and is the treatment of the first choice for neonatal icterus. Hypocalcemia is one of the lesser-known complications of phototherapy. Some studies have shown a relationship between increased urinary calcium excretion and phototherapy-induced hypocalcemia. We aimed to assess the effect of phototherapy on urinary calcium excretion in term neonates. This before-after study was pe...

  9. Selective renal vasoconstriction, exaggerated natriuresis and excretion rates of exosomic proteins in essential hypertension

    Damkjaer, M.; Jensen, Pia Hønnerup; Schwämmle, Veit;

    2014-01-01

    AimIn essential hypertension (EH), the regulation of renal sodium excretion is aberrant. We hypothesized that in mild EH, (i) abnormal dynamics of plasma renin concentration (PRC) and atrial natriuretic peptide (ANP) are responsible for the exaggerated natriuresis, and (ii) exosomic protein......). Excretion rates of exosome-related urinary proteins including apical membrane transporters were determined by proteomics-based methods. ResultsIn patients, baseline renal vascular conductance was reduced (-44%, P...

  10. Urinary Sex Steroid Excretion Levels During a Soy Intervention Among Young Girls: A Pilot Study

    Maskarinec, Gertraud; Morimoto, Yukiko; Franke, Adrian A.; Novotny, Rachel; Nordt, Frank J.; Stanczyk, Frank Z

    2005-01-01

    Soy intake early in life may protect against breast cancer later in life, possibly by altering sex hormone metabolism. We evaluated the feasibility of assessing urinary sex steroid excretion among 20 young girls aged 8–14 yr in an 8-wk trial. The girls consumed one daily soy serving, collected weekly overnight urine samples, and reported Tanner stages for breast and pubic hair development. Sex steroid excretion was measured in duplicate by gas chromatography-mass spectrometry and adjusted for...

  11. Organic acid excretion in Penicillium ochrochloron increases with ambient pH

    PamelaVrabl

    2012-04-01

    Confirming our hypothesis, the main result demonstrated that organic acid excretion in P. ochrochloron was enhanced at high external pH levels compared to low pH levels independent of the tested strain, nutrient limitation and cultivation method. We discuss these findings against the background of three hypotheses explaining organic acid excretion in filamentous fungi, i.e. overflow metabolism, charge balance and aggressive acidification hypothesis.

  12. Clinical usefulness of urinary 3-methylhistidine excretion in indicating muscle protein breakdown.

    Elia, M.; Carter, A; Bacon, S; Winearls, C G; Smith, R.

    1981-01-01

    Urinary excretion of the post-translationally modified amino-acid 3-methylhistidine, derived from the contractile proteins actin and myosin, was measured in patients with conditions associated with nitrogen loss. The ratio of 3-methylhistidine:creatinine excretion, a measure of the fractional catabolic rate of myofibrillar protein was increased in severe injury, thyrotoxicosis, neoplastic disease, prednisolone administration, and sometimes Duchenne muscular dystrophy. In myxoedema, osteomalac...

  13. Neurogenic hypertension associated with an excessively high excretion rate of catecholamine metabolites.

    Funck-Brentano, C; Pagny, J Y; Menard, J

    1987-01-01

    A 60 year old hypertensive patient suffered several cerebral infarctions. A phaeochromocytoma was suspected because the excretion rates of vanillylmandelic acid and its methoxy derivatives were raised and the patient had hypertensive crises. No tumour was found, however, by 131mI-iodobenzylguanidine scintigraphy and computed tomography of the abdomen. Moreover, the enhanced orthostatic plasma catecholamine response suggested that the high excretion rates of catecholamine metabolites were more...

  14. Effect of disturbance of the gastrointestinal microflora on the faecal excretion of Fusobacterium necrophorum biovar A.

    Smith, G. R.; Thornton, E. A.

    1993-01-01

    Oral pretreatment of mice with either a mixture of kanamycin and erythromycin or metronidazole to modify the gut microflora greatly enhanced the faecal excretion of Fusobacterium necrophorum biovar A given by mouth. This lends support to the suggestion that disturbance of the gastrointestinal microflora in animals such as cattle, which often carry the organism in the rumen, may lead to intestinal multiplication and faecal excretion, thereby providing a source of infection that may lead to nec...

  15. Determination of the excretion rate of uranium taken in from natural sources

    Based on the substantial amount of data collected by the incorporation measuring and monitoring office of Siemens AG, the natural excretion of U-238 was determined by human faeces analysis. The average excretion rate was 21 - 26 mBq per sample and day. Another value determined was the ratio between U-234 and U-238, which was found to be 2.0 on average in the population examined. (orig./CB)

  16. Urinary sulphate excretion and progression of diabetic nephropathy in Type 1 diabetes

    Andrésdóttir, G; Bakker, S J L; Hansen, H P; Parving, H-H; Rossing, P

    2013-01-01

    Hydrogen sulphide levels are reduced in many disease states, including diabetes and end-stage renal disease. We aimed to determine whether urinary sulphate excretion, as a proxy for hydrogen sulphide, was associated with progression of diabetic nephropathy.......Hydrogen sulphide levels are reduced in many disease states, including diabetes and end-stage renal disease. We aimed to determine whether urinary sulphate excretion, as a proxy for hydrogen sulphide, was associated with progression of diabetic nephropathy....

  17. Associations of ambulatory blood pressure with urinary caffeine and caffeine metabolite excretions.

    Guessous, Idris; Pruijm, Menno; Ponte, Belén; Ackermann, Daniel; Ehret, Georg; Ansermot, Nicolas; Vuistiner, Philippe; Staessen, Jan; Gu, Yumei; Paccaud, Fred; Mohaupt, Markus; Vogt, Bruno; Pechère-Bertschi, Antoinette; Pechère-Berstchi, Antoinette; Martin, Pierre-Yves; Burnier, Michel; Eap, Chin B; Bochud, Murielle

    2015-03-01

    Intake of caffeinated beverages might be associated with reduced cardiovascular mortality possibly via the lowering of blood pressure. We estimated the association of ambulatory blood pressure with urinary caffeine and caffeine metabolites in a population-based sample. Families were randomly selected from the general population of Swiss cities. Ambulatory blood pressure monitoring was conducted using validated devices. Urinary caffeine, paraxanthine, theophylline, and theobromine excretions were measured in 24 hours urine using ultrahigh performance liquid chromatography tandem mass spectrometry. We used mixed models to explore the associations of urinary excretions with blood pressure although adjusting for major confounders. The 836 participants (48.9% men) included in this analysis had mean age of 47.8 and mean 24-hour systolic and diastolic blood pressure of 120.1 and 78.0 mm Hg. For each doubling of caffeine excretion, 24-hour and night-time systolic blood pressure decreased by 0.642 and 1.107 mm Hg (both P values <0.040). Similar inverse associations were observed for paraxanthine and theophylline. Adjusted night-time systolic blood pressure in the first (lowest), second, third, and fourth (highest) quartile of paraxanthine urinary excretions were 110.3, 107.3, 107.3, and 105.1 mm Hg, respectively (P trend <0.05). No associations of urinary excretions with diastolic blood pressure were generally found, and theobromine excretion was not associated with blood pressure. Anti-hypertensive therapy, diabetes mellitus, and alcohol consumption modify the association of caffeine urinary excretion with systolic blood pressure. Ambulatory systolic blood pressure was inversely associated with urinary excretions of caffeine and other caffeine metabolites. Our results are compatible with a potential protective effect of caffeine on blood pressure. PMID:25489060

  18. Corticosterone excretion patterns and affiliative behavior over development in ravens (Corvus corax)

    Stöwe, Mareike; Bugnyar, Thomas; Schloegl, Christian; Heinrich, Bernd; Kotrschal, Kurt; Möstl, Erich

    2007-01-01

    Averse effects of social stress may be buffered by the presence of social allies, which mainly has been demonstrated in mammals and recently also in birds. However, effects of socio-positive behavior prior to fledging in relation to corticosterone excretion in altricial birds have not been investigated yet. We here monitored corticosterone excretion patterns in three groups of hand raised juvenile ravens (n=5, 6 and 11) in the nest, post-fledging (May–July) and when ravens would be independen...

  19. Excretion masses and environmental occurrence of antibiotics in typical swine and dairy cattle farms in China.

    Zhou, Li-Jun; Ying, Guang-Guo; Liu, Shan; Zhang, Rui-Quan; Lai, Hua-Jie; Chen, Zhi-Feng; Pan, Chang-Gui

    2013-02-01

    This paper evaluated the excretion masses and environmental occurrence of 11 classes of 50 antibiotics in six typical swine and dairy cattle farms in southern China. Animal feeds, wastewater and solid manure samples as well as environmental samples (soil, stream and well water) were collected in December 2010 from these farms. Twenty eight antibiotics, including tetracyclines, bacitracin, lincomycin, sulfonamides, fluoroquinolones, ceftiofur, trimethoprim, macrolides, and florfenicol, were detected in the feeds, animal wastes and receiving environments. The normalized daily excretion masses per swine and cattle were estimated to be 18.2mg/day/swine and 4.24 mg/day/cattle. Chlortetracycline (11.6 mg/day/swine), bacitracin (3.81 mg/day/swine), lincomycin (1.19 mg/day/swine) and tetracycline (1.04 mg/day/swine) were the main contributors to the normalized daily excretion masses of antibiotics per swine, while chlortetracycline (3.66 mg/day/cattle) contributed 86% of the normalized daily excretion masses of antibiotics per cattle. Based on the survey of feeds and animal wastes from the swine farms and interview with the farmers, antibiotics excreted by swine were mainly originated from the feeds, while antibiotics excreted by dairy cattle were mainly from the injection route. If we assume that the swine and cattle in China excrete the same masses of antibiotics as the selected livestock farms, the total excretion mass by swine and cattle per annum in China could reach 3,080,000 kg/year and 164,000 kg/year. Various antibiotics such as sulfonamides, tetracyclines, fluroquinolones, macrolides, trimethoprim, lincomycin and florfenicol were detected in well water, stream and field soil, suggesting that livestock farms could be an important pollution source of various antibiotics to the receiving environments. PMID:23268145

  20. Q Fever in Pregnant Goats: Pathogenesis and Excretion of Coxiella burnetii

    Hendrik-Jan Roest; Betty van Gelderen; Annemieke Dinkla; Dimitrios Frangoulidis; Fred van Zijderveld; Johanna Rebel; Lucien van Keulen

    2012-01-01

    Coxiella burnetii is an intracellular bacterial pathogen that causes Q fever. Infected pregnant goats are a major source of human infection. However, the tissue dissemination and excretion pathway of the pathogen in goats are still poorly understood. To better understand Q fever pathogenesis, we inoculated groups of pregnant goats via the intranasal route with a recent Dutch outbreak C. burnetii isolate. Tissue dissemination and excretion of the pathogen were followed for up to 95 days after ...

  1. Absorption, excretion, and retention of selenium from a high selenium yeast in men with a high intake of selenium

    Bügel, Susanne; Larsen, Erik H.; Sloth, Jens J; Flytlie, Knut; Overvad, Kim; Steenberg, Lars C.; Moesgaard, Sven

    2008-01-01

    Objective: The purpose of this study was to evaluate the pharmacokinetics of a single dose of Se from yeast given to humans with a habitual long-term daily intake at a supra-nutritional level. Research Methods & Procedures: Twelve healthy males with a daily supplemental intake of 300 mg Se as selenised yeast over 10 weeks were supplemented with a single dose of 327 mg as stable 77Se incorporated into selenised yeast manufactured by the same standardised process (SelenoPrecise©, Pharma Nord, D...

  2. Human systemic exposure to [14C]-paraphenylenediamine-containing oxidative hair dyes: Absorption, kinetics, metabolism, excretion and safety assessment

    Nohynek, G.J.; Skare, J.A.; Meuling, W.J.A.; Wehmeyer, K.R.; Bie, A.T.H.J. de; Vaes, W.H.J.; Dufour, E.K.; Fautz, R.; Steiling, W.; Bramante, M.; Toutain, H.

    2015-01-01

    Systemic exposure was measured in humans after hair dyeing with oxidative hair dyes containing 2.0% (A) or 1.0% (B) [14C]-p-phenylenediamine (PPD). Hair was dyed, rinsed, dried, clipped and shaved; blood and urine samples were collected for 48 hours after application. [14C] was measured in all mater

  3. Effect of Hibiscus sabdariffa L. Dried Calyx Ethanol Extract on Fat Absorption-Excretion, and Body Weight Implication in Rats

    O. Carvajal-Zarrabal

    2009-01-01

    , and . Only did not show significant increases in weight, food consumption and efficiency compared to . The opposite occurred in group which showed a significant decrease for these three parameters. The responses were similar to , with the exception of food consumption. In both and groups, no body weight loss was observed; however, only in the latter group was there a significantly greater amount of fatty acids found in feces. A collateral effect emerging from the study is that components of Hs extract at the intermediate and greater concentrations used in this experiment could be considered possible antiobesity agents.

  4. Short-term starvation effects on nitrogen and phosphorus excretion by the chaetognath Sagitta enflata

    Szyper, James P.

    1981-12-01

    Freshly captured Sagitta enflata exhibited specific excretion rates of ammonium and phosphate (expressed as percentage body content of N or P per hour) that were not significantly related to the size of individual animals. The degree of crowding in experimental vessels was positively correlated with specific excretion rates of ammonium. Excretion rates, under conditions that precluded feeding, decreased sharply during the first several hours' incubation time, approaching the rates exhibited by animals starved overnight. The practice of holding freshly captured zooplankton for a time before determining excretion rates may seriously affect those rates, if the animals are unable to feed. Animals captured during the day in Kaneohe Bay, Hawaii, having no food items in their guts, had mean specific excretion rates (± S.D.) of 0·81±0·51% body content of N h -1 for ammonium, and 1·29±1·24% body content of P h -1 for phosphate. Minimal estimates of natural excretion rates, made from the first hour of incubation in further experiments, were 1·19±0·47% h -1 for nitrogen and 3·8±3·95% h -1 for phosphorus. Sagitta is not a large contributor to nutrient regeneration in Kaneohe Bay.

  5. Human urinary excretion profile after smoking and oral administration of [14C]delta 1-tetrahydrocannabinol

    The urinary excretion profiles of delta 1-tetrahydrocannabinol (delta 1-THC) metabolites have been evaluated in two chronic and two naive marijuana users after smoking and oral administration of [14C]delta 1-THC. Urine was collected for five days after each administration route and analyzed for total delta 1-THC metabolites by radioactivity determination, for delta 1-THC-7-oic acid by high-performance liquid chromatography, and for cross-reacting cannabinoids by the EMIT d.a.u. cannabinoid assay. The average urinary excretion half-life of 14C-labeled delta 1-THC metabolites was calculated to be 18.2 +/- 4.9 h (+/- SD). The excretion profiles of delta 1-THC-7-oic acid and EMIT readings were similar to the excretion profile of 14C-labeled metabolites in the naive users. However, in the chronic users the excretion profiles of delta 1-THC-7-oic acid and EMIT readings did not resemble the radioactive excretion due to the heavy influence from previous Cannabis use. Between 8-14% of the radioactive dose was recovered in the urine in both user groups after oral administration. Lower urinary recovery was obtained both in the chronic and naive users after smoking--5 and 2%, respectively

  6. Excretion of 14C-labeled cyanide in rats exposed to chronic intake of potassium cyanide

    The excretion of an acute dose of 14C-labeled cyanide in urine, feces, and expired air was studied in rats exposed to daily intake of unlabeled KCN in the diet for 6 weeks. Urinary excretion was the main route of elimination of cyanide carbon in these rats, accounting for 83% of the total excreted radioactivity in 12 hr and 89% of the total excreted radioactivity in 24 hr. The major excretion metabolite of cyanide in urine was thiocyanate, and this metabolite accounted for 71 and 79% of the total urinary activity in 12 hr and 24 hr, respectively. The mean total activity excreted in expired air after 12 hr was only 4%, and this value did not change after 24 hr. Of the total activity in expired air in 24 hr, 90% was present as carbon dioxide and 9% as cyanide. When these results were compared with those observed for control rats, it was clear that the mode of elimination of cyanide carbon in both urine and breath was not altered by the chronic intake of cyanide

  7. Intestinal perfusion in the study of intestinal absorption

    Several techniques for studying absorption by means of intestinal perfusion have been developed. While the principle is simple, the practice is complicated by absorption of the solvent and by excretion of fluid into the lumen. To improve reliability a ''marker'' is incorporated into the system; it should behave as nearly as possible like the nutrient of interest, except that it should be unabsorbable. A great many markers, including several labelled with radionuclides, have been developed for use with numerous nutrients, and perfusion methods using double or triple tubes or occlusive balloons have been tested. The perfusion technique is too complicated for routine diagnostic use, but it offers at present the only possibility of studying the function of defined sections of the small intestine in the intact human. (author)

  8. Mineral absorption in relation to nutritional ecology of reindeer

    H. Staaland

    1986-06-01

    Full Text Available This paper addresses the way which absorption of minerals relate to nutritional ecology and mineral conservation processes. A latin square designed experiment was used to assess the effects of diet on mineral (Ca, Mg, K, Na absorption processes in reindeer (Rangifer tarandus L.. Three male calves were fed 3 different diets: concentrate with 25% grass meal (RF-71, lichens, and a mixed diet of lichens and RF-71. Two other male calves were fed the lichen or mixed diet, supplemented with 4 g Ca/day. Ca supplementation significantly increased fecal Ca excretion, reduced the excretion of K and Mg, but had no significant effect on Na excretion. Rates of intake and fecal exretion of Ca, Mg and K were highly correlated (P<0.001, while no correlations were found for Na. Negative digestibilities of Ca, Mg and K, and a positive Na digestibility were noted for the lichen diet. For the other diets, all minerals were in positive digestibility, and Ca supplements increased the digestibility of all minerals. Digesta from different sections of the alimentary tract were collected after termination of the experiment. Alimentary pools of Ca and K were equal for animals fed lichen or RF-71, whereas the Na pool was largest on the lichen diet and the Mg pool largest on the RF-71 diet. Rumen turnover time (rumen mineral pool size/daily mineral intake was consistently less than 3 days for Ca and Mg, but was 22 and 82 days for Na on the RF-71 and lichen diets respectively. Estimates of mineral exchange in various parts of the tract showed that the intestines play and important role in scavanging endogenously secreted minerals. Results are discussed with respect to mineral binding by lichens and the possible role of natural mineral supplements in the nutritional ecology of reindeer.

  9. Viscosity of iodinated contrast agents during renal excretion

    Objective: Modern iodinated non-ionic contrast agents (CAs) can be classified based on their molecular structure into monomeric and dimeric CAs and have at comparable iodine concentrations a different viscosity and osmolality. During their renal excretion, CAs are concentrated in the renal tubuli which might enhance the viscosity difference between monomeric and dimeric CAs. The viscosity of a CA might have an underestimated importance for renal safety, as suggested by recent publications. In this study, we investigated the viscosities of CAs at the concentrations expected to be present in renal tubules. This concentration process was simulated in vitro using dialysis. Furthermore, we investigated urine viscosity and urine flow in rodents after administration of several non-ionic monomeric and dimeric CAs. Materials and methods: To estimate the viscosity of the CAs in vivo, we performed an in vitro dialysis of monomeric and dimeric CAs at various physiological osmolalities of the renal tubulus (290, 400, 500, 700 and 1000 mOsm/kg H2O). Following the dialysis, the iodine concentrations and the viscosities of the CAs were determined. Furthermore, to investigate the concentration process in vivo, we measured the urine viscosity and the urine flow in Han Wister rats after the administration of Iopromide, Iohexol, Ioversol, Iomeprol, Iodixanol, and Iosimenol at comparable iodine concentrations. As a control, saline was injected at the same volume. Results: In vitro dialysis of the dimeric CA increased the iodine concentration and strongly increased the viscosity at all tested osmolalities. In contrast, for the monomeric agents an increase in concentration and viscosity was observed only at 700 as well 1000 mOsm/kg H2O but to a lesser extent. In summary, dialysis strongly enhanced the viscosity differences between the non-ionic monomeric and dimeric CAs. The administration of dimeric CAs leads to a strong increase in urine viscosity; this was not observed for the

  10. Viscosity of iodinated contrast agents during renal excretion

    Jost, Gregor, E-mail: Gregor.Jost@bayer.com [TRG Diagnostic Imaging, Bayer Schering Pharma AG, Berlin (Germany); Lengsfeld, Philipp, E-mail: Philipp.Lengsfeld@bayer.com [Global Medical Affairs Diagnostic Imaging, Bayer Schering Pharma AG, Berlin (Germany); Lenhard, Diana C., E-mail: Diana.Lenhard@bayer.com [TRG Diagnostic Imaging, Bayer Schering Pharma AG, Berlin (Germany); Pietsch, Hubertus, E-mail: Hubertus.Pietsch@bayer.com [TRG Diagnostic Imaging, Bayer Schering Pharma AG, Berlin (Germany); Huetter, Joachim, E-mail: Joachim.Huetter@bayer.com [TRG Diagnostic Imaging, Bayer Schering Pharma AG, Berlin (Germany); Sieber, Martin A., E-mail: Martin.Sieber@bayer.com [TRG Diagnostic Imaging, Bayer Schering Pharma AG, Berlin (Germany)

    2011-11-15

    Objective: Modern iodinated non-ionic contrast agents (CAs) can be classified based on their molecular structure into monomeric and dimeric CAs and have at comparable iodine concentrations a different viscosity and osmolality. During their renal excretion, CAs are concentrated in the renal tubuli which might enhance the viscosity difference between monomeric and dimeric CAs. The viscosity of a CA might have an underestimated importance for renal safety, as suggested by recent publications. In this study, we investigated the viscosities of CAs at the concentrations expected to be present in renal tubules. This concentration process was simulated in vitro using dialysis. Furthermore, we investigated urine viscosity and urine flow in rodents after administration of several non-ionic monomeric and dimeric CAs. Materials and methods: To estimate the viscosity of the CAs in vivo, we performed an in vitro dialysis of monomeric and dimeric CAs at various physiological osmolalities of the renal tubulus (290, 400, 500, 700 and 1000 mOsm/kg H{sub 2}O). Following the dialysis, the iodine concentrations and the viscosities of the CAs were determined. Furthermore, to investigate the concentration process in vivo, we measured the urine viscosity and the urine flow in Han Wister rats after the administration of Iopromide, Iohexol, Ioversol, Iomeprol, Iodixanol, and Iosimenol at comparable iodine concentrations. As a control, saline was injected at the same volume. Results: In vitro dialysis of the dimeric CA increased the iodine concentration and strongly increased the viscosity at all tested osmolalities. In contrast, for the monomeric agents an increase in concentration and viscosity was observed only at 700 as well 1000 mOsm/kg H{sub 2}O but to a lesser extent. In summary, dialysis strongly enhanced the viscosity differences between the non-ionic monomeric and dimeric CAs. The administration of dimeric CAs leads to a strong increase in urine viscosity; this was not observed for

  11. Zeeman atomic absorption spectroscopy

    A new method of background correction in atomic absorption spectroscopy has recently been introduced, based on the Zeeman splitting of spectral lines in a magnetic field. A theoretical analysis of the background correction capability observed in such instruments is presented. A Zeeman atomic absorption spectrometer utilizing a 50 Hz sine wave modulated magnetic field is described. (Auth.)

  12. Nutrition and magnesium absorption.

    Brink, E.J.

    1992-01-01

    The influence of various nutrients present in dairy products and soybean-based products on absorption of magnesium has been investigated. The studies demonstrate that soybean protein versus casein lowers apparent magnesium absorption in rats through its phytate component. However, true magnesium abs

  13. Petawatt laser absorption bounded

    Levy, Matthew C; Tabak, Max; Libby, Stephen B; Baring, Matthew G

    2014-01-01

    The interaction of petawatt ($10^{15}\\ \\mathrm{W}$) lasers with solid matter forms the basis for advanced scientific applications such as table-top particle accelerators, ultrafast imaging systems and laser fusion. Key metrics for these applications relate to absorption, yet conditions in this regime are so nonlinear that it is often impossible to know the fraction of absorbed light $f$, and even the range of $f$ is unknown. Here using a relativistic Rankine-Hugoniot-like analysis, we show for the first time that $f$ exhibits a theoretical maximum and minimum. These bounds constrain nonlinear absorption mechanisms across the petawatt regime, forbidding high absorption values at low laser power and low absorption values at high laser power. For applications needing to circumvent the absorption bounds, these results will accelerate a shift from solid targets, towards structured and multilayer targets, and lead the development of new materials.

  14. Association of Urinary Calcium Excretion with Serum Calcium and Vitamin D Levels

    Rathod, Anita; Bonny, Olivier; Guessous, Idris; Suter, Paolo M.; Conen, David; Erne, Paul; Binet, Isabelle; Gabutti, Luca; Gallino, Augusto; Muggli, Franco; Hayoz, Daniel; Péchère-Bertschi, Antoinette; Paccaud, Fred

    2015-01-01

    Background and objectives Population-based data on urinary calcium excretion are scarce. The association of serum calcium and circulating levels of vitamin D [25(OH)D2 or D3] with urinary calcium excretion in men and women from a population-based study was explored. Design, settings, participants, & measurements Multivariable linear regression was used to explore factors associated with square root–transformed 24-hour urinary calcium excretion (milligrams per 24 hours) taken as the dependent variable with a focus on month-specific vitamin D tertiles and serum calcium in the Swiss Survey on Salt Study. Results In total, 624 men and 669 women were studied with mean ages of 49.2 and 47.0 years, respectively (age range=15–95 years). Mean urinary calcium excretion was higher in men than in women (183.05 versus 144.60 mg/24 h; P<0.001). In adjusted models, the association (95% confidence interval) of square root urinary calcium excretion with protein–corrected serum calcium was 1.78 (95% confidence interval, 1.21 to 2.34) mg/24 h per milligram per deciliter in women and 0.59 (95% confidence interval, −0.11 to 1.29) mg/24 h per milligram per deciliter in men. Men in the third 25(OH)D3 tertile had higher square root urinary calcium excretion than men in the first tertile (0.99; 95% confidence interval, 0.36 to 1.63 mg/24 h per nanogram per milliliter), and the corresponding association was 0.32 (95% confidence interval, −0.22 to 0.85) mg/24 h per nanogram per milliliter in women. These sex differences were more marked under conditions of high urinary sodium or urea excretions. Conclusions There was a positive association of serum calcium with urinary calcium excretion in women but not men. Vitamin 25(OH)D3 was associated with urinary calcium excretion in men but not women. These results suggest important sex differences in the hormonal and dietary control of urinary calcium excretion. PMID:25518946

  15. Absorção e redistribuição de nitrogênio (15N em Citrus mitis Bl Absorption and distribution of nitrogen (15N in Citrus mitis Bl

    WILLIAM NATALE

    2002-04-01

    Full Text Available Com a avaliação da eficiência de uso do nitrogênio, tem-se melhor entendimento dos aspectos nutricionais e respostas à adubação. O presente ensaio teve por objetivo estudar a absorção e redistribuição de nitrogênio (15N em Citrus mitis Bl.. As fontes de fertilizante utilizadas foram: sulfato de amônio, uréia, nitrato de cálcio e nitrato de potássio. O delineamento experimental utilizado foi inteiramente casualizado, com 4 tratamentos e 3 repetições. Foram realizadas duas amostragens, aos 10 e 20 dias após a aplicação do adubo marcado, a fim de determinar os teores de N nas diferentes partes da planta. Através dos resultados, verificou-se que não houve efeito dos tratamentos sobre o peso de matéria seca e conteúdo de N nas plantas. A eficiência de absorção de N variou com a natureza do fertilizante nitrogenado e com a época de amostragem, ao passo que a redistribuição do N não foi afetada. A eficiência máxima de absorção do N variou de 14% (uréia e 31% (sulfato de amônio, respectivamente, aos 10 e 20 dias após a aplicação do 15N.The absorption of nitrogen fertiliser labelled with 15N was studied in Citrus mitis Bl. The sources of N fertiliser used were ammonium sulfate, urea, calcium nitrate and potassium nitrate. All of them were applied in soil. A completely randomised design was utilised. The distribution of N in the different parts of the plants was determined after 10 and 20 days. There were no difference among treatments on plant dry matter weight and N content. The highest recovery of labelled N after 10 days was obtained with urea (14%. In the second sampling (20 days, the highest recovery was accomplished with ammonium sulfate (31%.

  16. Urinary iodine excretion in relation to goiter prevalence in households of goiter endemic and non endemic regions of Ethiopia

    A Survey of goiter prevalence, among population of five endemic and four non endemic regions of Ethiopia was carried out prior to the distribution of iodate d salt. urine samples were collected from 327 subjects selected by systematic random sampling from endemic and 276 taken as non endemic. The lowest mean urinary iodine excretion (UIE) value was recorded in Bure (22 micro gl/day) and the highest in Alemmaya (148 micro gl/day). The highest goiter rate ( percent TGR) was recorded in Sawla 55.6 %) and the lowest (0.6 %) in Yabello. Iodine content of drinking was in the range of 0.4 - 48.5 micro gl. Iodine content of water source was correlated positively ( r0.8399) with the mean of UIE and TGR, however, indicates that sites considered as non endemic seem to be affected by iodine deficiency. The study results urge the need for intervention in controlling Iodine Deficiency Disorders. 3 tab

  17. Nitrogen excretion in dairy cow, beef and veal cattle, pig, and rabbit farms in Northern Italy

    Giovanni Bittante

    2010-01-01

    Full Text Available Reference values for N excretion of different livestock production systems are required for the application of the Nitrate Directive (91/676/EC. A survey aimed to estimate N excretion from on-farm measurements of feed consumption and performance of dairy cows (104 herds, 9,984 cows, growing cattle (40 farms, 40,157 young bulls, veal calves (34 farms, 49,206 calves, growing pigs (39 farms, 161,278 pigs and rabbits (54 farms, 65,664 reproducing does was conducted in Veneto from 2002 to 2003. N excretion was computed as the difference between N consumption and N retained in animal products. Dairy cow yielded 8,366 ± 1,646 kg/year of milk, consumed 6,600 ± 928 kg/year of DM, containing 2.45 ± 0.2 % DM of N, and excreted 116 ± 25 kg of N/year. No significant correlation was found between milk yield and N excretion, but the correlation between dietary N concentration and N excretion was significant (r=0.66. For growing cattle, the following mean values were achieved: daily gain 1.25 ± 0.19 kg/d; feed conversion ratio 6.9 ± 0.9 kg of DM/kg, rounds/year 1.66 ± 0.38. Nitrogen consumed, retained and excreted were, respectively, 68.7 ± 5.4, 11.4 ± 1.9 and 57.3 ± 4.9 kg/place/year. For veal calves, N consumed was 24.1 ± 1.9 kg/place/year, 12.1 ± 0.8 kg of which were retained in the body and 12.0 ± 1.5 kg were excreted. For heavy pig production, N consumed, per place and per year, averaged 19.0 ± 1.9 kg, N retained was 5.2 ± 0.5 kg and N excreted was 13.8 ± 0.4 kg. In the close-cycle rabbit farms, the doe and the relative growing rabbits (43 sold per year consumed 11.2 ± 2.2 kg, retained 3.8 ± 0.7 kg and excreted 7.4 ± 1.5 kg N/doe/year. Nitrogen excretion estimated in this work can be considered as representative of some of the main animal production systems of the North-East of Italy. These values should not be considered as fixed, otherwise the implementation of the various strategies to reduce N excretion would not be possible. They

  18. Factors Altering Pyruvate Excretion in a Glycogen Storage Mutant of the Cyanobacterium, Synechococcus PCC7942.

    Benson, Phoebe J; Purcell-Meyerink, Diane; Hocart, Charles H; Truong, Thy T; James, Gabriel O; Rourke, Loraine; Djordjevic, Michael A; Blackburn, Susan I; Price, G D

    2016-01-01

    Interest in the production of carbon commodities from photosynthetically fixed CO2 has focused attention on cyanobacteria as a target for metabolic engineering and pathway investigation. We investigated the redirection of carbon flux in the model cyanobacterial species, Synechococcus elongatus PCC 7942, under nitrogen deprivation, for optimized production of the industrially desirable compound, pyruvate. Under nitrogen limited conditions, excess carbon is naturally stored as the multi-branched polysaccharide, glycogen, but a block in glycogen synthesis, via knockout mutation in the gene encoding ADP-glucose pyrophosphorylase (glgC), results in the accumulation of the organic acids, pyruvate and 2-oxoglutarate, as overflow excretions into the extracellular media. The ΔglgC strain, under 48 h of N-deprivation was shown to excrete pyruvate for the first time in this strain. Additionally, by increasing culture pH, to pH 10, it was possible to substantially elevate excretion of pyruvate, suggesting the involvement of an unknown substrate/proton symporter for export. The ΔglgC mutant was also engineered to express foreign transporters for glucose and sucrose, and then grown photomixotrophically with exogenous organic carbon supply, as added 5 mM glucose or sucrose during N- deprivation. Under these conditions we observed a fourfold increase in extracellular pyruvate excretion when glucose was added, and a smaller increase with added sucrose. Although the magnitude of pyruvate excretion did not correlate with the capacity of the ΔglgC strain for bicarbonate-dependent photosynthetic O2 evolution, or with light intensity, there was, however, a positive correlation observed between the density of the starter culture prior to N-deprivation and the final extracellular pyruvate concentration. The factors that contribute to enhancement of pyruvate excretion are discussed, as well as consideration of whether the source of carbon for pyruvate excretion might be derived from

  19. Molecular absorption in Cen A on VLBI scales

    Van Langevelde, H J; Beasley, A

    2004-01-01

    Centaurus A, the nearest AGN shows molecular absorption in the millimeter and radio regime. By observing the absorption with VLBI, we try to constrain the distribution of the gas, in particular whether it resides in the circumnuclear region. Analysis of VLBA observations in four OH and two H2CO transitions is presented here, as well as molecular excitation models parameterized with distance from the AGN. We conclude that the gas is most likely associated with the tilted molecular ring structure observed before in molecular emission and IR continuum. The formaldehyde absorption shows small scale absorption which requires a different distribution than the hydroxyl.

  20. Quasar Absorption Studies

    Mushotzky, Richard (Technical Monitor); Elvis, Martin

    2004-01-01

    The aim of the proposal is to investigate the absorption properties of a sample of inter-mediate redshift quasars. The main goals of the project are: Measure the redshift and the column density of the X-ray absorbers; test the correlation between absorption and redshift suggested by ROSAT and ASCA data; constrain the absorber ionization status and metallicity; constrain the absorber dust content and composition through the comparison between the amount of X-ray absorption and optical dust extinction. Unanticipated low energy cut-offs where discovered in ROSAT spectra of quasars and confirmed by ASCA, BeppoSAX and Chandra. In most cases it was not possible to constrain adequately the redshift of the absorber from the X-ray data alone. Two possibilities remain open: a) absorption at the quasar redshift; and b) intervening absorption. The evidences in favour of intrinsic absorption are all indirect. Sensitive XMM observations can discriminate between these different scenarios. If the absorption is at the quasar redshift we can study whether the quasar environment evolves with the Cosmic time.

  1. Absorção e distribuição de chumbo em plantas devetiver, jureminha e algaroba Absorption and distribution of lead in vetiver, mimosa and mesquite plants

    Jailson do Carmo Alves

    2008-06-01

    , and studies concerning heavy metal tolerance, absorption and distribution in plants are essential for the success of such programs. This study was carried out to evaluate the tolerance, absorption and distribution of lead (Pb in vetiver grass [Vetiveria zizanioides (L. Nash], mimosa [Desmanthus virgatus (L. Willd] and mesquite trees [Prosopis juliflora (SW DC] subjected to increasing lead doses in solution. The experiment was conducted under a screenhouse, at the DSER/CCA/UFPB, Areia-PB, Brazil. The species were grown in nutrient solution containing increasing Pb levels (0, 50, 100 and 200 mg L-1 during a 45-day exposure period. An entirely randomized split-plot design was used with three replicates. The main plot was represented by the plant species and the subplot by Pb levels. The increased Pb levels caused significant reductions of dry mass of the root, shoot and whole plant (root + shoot in the three species under study. Based on critical toxicity levels, the tolerance of vetiver to Pb contamination was higher than in the other species. In vetiver and mesquite plants, the roots were the component most sensitive to Pb contamination, whereas a similar response to Pb by all plant components was observed for mimosa. Total Pb concentrations and content in plant compartments were significantly affected by the increasing Pb levels in solution, and a higher accumulation of this element was observed in the roots of the three species under study. The highest Pb concentration and content were found in all compartments of vetiver, which suggests a high potential of this grass for phytoremediation of Pb-contaminated areas.

  2. The effects of the calcium-restricted diet of urolithiasis patients with absorptive hypercalciuria type II on risk factors for kidney stones and osteopenia

    Faassen, A. van; Ploeg, E.M.C. van der; Habets, H.M.L.; Meer, R. van der; Hermus, R.J.J.; Janknegt, R.A.

    1998-01-01

    The calcium (Ca)-restricted diet of urolithiasis patients with absorptive hypercalciuria type II may decrease Ca excretion but increase biochemical markers of risk for osteopenia. We randomly allocated 25 patients from six hospitals into an experimental group (Ca restriction to 500 mg/day, oxalate-r

  3. Estimation of molar absorptivities and pigment sizes for eumelanin and pheomelanin using femtosecond transient absorption spectroscopy

    Piletic, Ivan R.; Matthews, Thomas E.; Warren, Warren S.

    2009-11-01

    Fundamental optical and structural properties of melanins are not well understood due to their poor solubility characteristics and the chemical disorder present during biomolecular synthesis. We apply nonlinear transient absorption spectroscopy to quantify molar absorptivities for eumelanin and pheomelanin and thereby get an estimate for their average pigment sizes. We determine that pheomelanin exhibits a larger molar absorptivity at near IR wavelengths (750nm), which may be extended to shorter wavelengths. Using the molar absorptivities, we estimate that melanin pigments contain ˜46 and 28 monomer units for eumelanin and pheomelanin, respectively. This is considerably larger than the oligomeric species that have been recently proposed to account for the absorption spectrum of eumelanin and illustrates that larger pigments comprise a significant fraction of the pigment distribution.

  4. The effect of plane of nutrition on the urinary purine derivative excretion in sheep and goats

    An experiment was conducted to determine the effect of plane of nutrition on purine derivative excretion and to develop a set of model equations that relate intake to the purine derivative (PD) excretion in sheep and goats. Four male Sabi sheep and four male Small-East African goats (four months old) were used. The trial was a 4 x 4 Latin square cross-over design to examine the response of PD excretion to feed intake. The four diets consisted of star grass (Cynodon nlemfuensis) hay fed ad libitum, and at 85, 70 or 55% of ad libitum. Total PD excretion increased with the increase in feed intake for both sheep and goats. However, the increase did not reach statistical significance (P > 0.05). The model equations relating digestible organic matter intake (X) to PD excretion (Y) were Y = 2.97 X + 0.15 (R2=0.72) and Y = 5.86 X - 0.33 (R2=0.99) for sheep and goats respectively. (author)

  5. Diurnal variation of the human urinary TRH excretion measured by radioimmunoassay

    Urine TRH was estimated by the radioimmunoassay which was accomplished according to the method of Bassiri and Utiger. Minimum detectable dose of TRH was 25 pg and recovery of TRH ranged from 72% to 112% in our laboratory. Intraassay coefficients of variation were 5.4% to 14.0% and interassay variations were 10.6% to 15.0%. Of the TRH analogues tested, only two (Ser-His-Pro-NH2, Thr-His-Pro-NH2) had potent reactivity to anti-TRH serum in large dose of 100 ng/tube. Urine samples were kept at -200C after adjusted to pH 3.0 because the inactivation of TRH in urine was markedly dependent on temperature and pH value. Using this radioimmunoassay, diurnal variation of the urinary TRH excretion at regular intervals in normal subjects was observed. Peak TRH excretion occurred arond early morning, while minimum of the excretion was observed around noon. Total urinary TRH excretion of 24 hours was 817-1579 ng (M+-SE: 1241+-89 ng) in normal subjects. In patients with chronic renal failure, urinary excretions of TRH was obviously lower than those of normal subjects. (auth.)

  6. Evaluation of nutrient excretion and retention in broilers submitted to different nutritional strategies

    AL Graña

    2013-06-01

    Full Text Available An experiment was carried out to evaluate the effects of different nutritional strategies on nitrogen (N, phosphorus (P and calcium (Ca balance and on copper (Cu, manganese (Mn and zinc (Zn excretion in broilers during the periods of 1 to 21 days and 1 to 46 days of age. Four hundred male Cobb-500 broilers were used. A randomized block experimental design was applied, including five treatments with eight replicates of 10 birds each. A five-phase feeding program was adopted (1-8, 9-21, 22-33, 34-40 and 41-46 days of age. Treatments consisted of a control diet (C with typical protein level and low amino acid supplementation; a reduced-protein diet supplemented with synthetic amino acids formulated on ideal protein concept (IP; C with phytase (C+PHY supplementation; C with inorganic-organic mineral supplementation (C+MIN; and a diet formulated on ideal protein (IP basis, and supplemented with phytase and organic and inorganic minerals (IP+PHY+MIN. IP and IP+PHY+MIN diets reduced nitrogen excretion in 13.6 and 13.1% respectively, and promoted the same nitrogen retention (g/bird and retention efficiency as compared to the diet with typical crude protein level. C+PHY and IP+PHY+MIN reduced phosphorus, calcium and manganese excretion, and improved phosphorus retention. C+MIN and IP+PHY+MIN reduced manganese excretion, but did not influence copper or zinc excretion.

  7. Patterns of 1-hydroxypyrene excretion in volunteers exposed to pyrene by the dermal route

    Viau, C.; Vyskocil, A. [University of Montreal, Montreal, PQ (Canada)

    1995-02-24

    The urinary excretion profiles following exposure to pyrene were established in one psoriasic patient under treatment with a coal tar-based shampoo and in two other volunteers exposed to a single dose of 100{mu}1 creosote and, in a separate experiment, to five consecutive daily dermal applications of 500{mu}g pyrene on 200 cm{sup 2} of the inner face of the forearms. Timed micturitions were collected for up to 48 h following exposure. Both in the psoriasic patient and in the volunteers exposed to creosote, the excretion peaks between 10 and 15 h after application and first-order apparent half lives of 11.5-15 h can be calculated for the elimination phase. Compatible with these observations, repeated exposure to pyrene in the volunteers causes an increase in peak and trough urinary 1-hydroxypyrene (1-OHP) values for the first few days following the first exposure. These results suggest that the difference between beginning-of-shift/beginning of work week and beginning-of-shift/end of work week 1-OHP excretion should reflect the average exposure of the week in workers having a constant exposure to pyrene. The difference between the beginning and end-of-shift excretion values of a given day should reflect the exposure of that day but the maximum excretion would be attained a few hours after termination of exposure.

  8. The variability and dietary dependence of urinary oxalate excretion in recurrent calcium stone formers.

    Brown, J M; Stratmann, G; Cowley, D M; Mottram, B M; Chalmers, A H

    1987-07-01

    Twenty-two recurrent calcium stone formers had 24-h urinary oxalate excretions on their home diets which were significantly greater than those of 30 normal subjects (0.48 +/- 0.23 mmol/d; mean +/- SD compared with 0.31 +/- 0.11; P less than 0.01). The stone formers also demonstrated marked day to day variability in oxalate excretion indicating that a single normal urinary oxalate measurement did not exclude significant hyperoxaluria at other times. On a hospital diet containing 1000 mg calcium per day, urinary oxalate excretion fell significantly from 0.48 +/- 0.23 mmol/d to 0.32 +/- 0.12; P less than 0.01. As the urinary calcium excretion in and out of hospital was similar, it seems unlikely that low calcium intake at home was responsible for the hyperoxaluria. All patients had recurrent symptomatic stone disease and had been advised to avoid foods rich in oxalate. Whilst poor compliance is a possible explanation for the variability in oxalate excretion, we believe it is more likely that there is an inadvertent intake of oxalogenic precursors in their diet. As normal subjects do not demonstrate hyperoxaluria on similar home diets, stone formers may have a metabolic defect in the handling of these precursors. PMID:3662388

  9. Biliary excretion of essential trace elements in rats under oxidative stress caused by selenium deficiency

    Yamasaki, Kosuke; Tsukada, Masamichi [Meiji University, School of Agriculture, Kawasaki, Kanagawa (Japan); Sakuma, Yasunobu; Sasaki, Junya; Matsuoka, Keisuke; Honda, Chikako; Endo, Kazutoyo [Showa Pharmaceutical University, Department of Physical Chemistry, Machida, Tokyo (Japan); Matsumoto, Ken-ichiro; Anzai, Kazunori [National Institute of Radiological Science, Research Center for Charged Particle Therapy, Chiba (Japan); Enomoto, Shuichi [The Institute of Physical and Chemical Research (RIKEN), Radioisotope Technology Division, Cyclotron Center, Wako, Saitama (Japan); Okayama University, Department of Analytical Chemistry, School of Pharmacy, Okayama (Japan)

    2011-11-15

    The excretion of essential trace elements, namely, Se, Sr, As, Mn, Co, V, Fe, and Zn into the bile of Se-deficient (SeD) Wistar male rats was studied using the multitracer (MT) technique, and instrumental neutron activation analysis (INAA). Normal and Se-control (SeC) rat groups were used as reference groups to compare the effects of Se levels on the behaviors of the essential trace elements. The excretion (% dose) of Se, Sr, As, Mn, Co, and V increased with Se levels in the liver. The biliary excretion of Mn and As dramatically enhanced for SeC rats compared with SeD rats, while that of V accelerated a little for SeC rats. The radioactivity levels of {sup 59}Fe and {sup 65}Zn in the MT tracer solution were insufficient to measure their excretion into bile. The role of glutathione and bilirubin for biliary excretion of the metals was discussed in relation to Se levels in rat liver. (orig.)

  10. Renal thorium and uranium excretion in non-exposed subjects: influence of age and gender

    The excretion of 238U and 232Th was investigated by ICP-MS in a group of 30 males (mean age 41 ± 18 years, range 7 to 73 years) and 33 females (43 ± 21 years, 11 to 84 years). For the thorium excretion, the geometric mean is 34 μBq/day (SD 1.90) for the whole group, 40 μBq/day (SD 2.01) for the males and 30 μBq/day (SD 1.78) for the females. The difference between the males and females is statistically insignificant. A certain increase in the excretion was observed with increasing age but the correlation coefficient of the linear relationship is statistically insignificant. For uranium, the geometric means (SD) for the whole group, the male subgroup, and the female subgroup, in μBq/day, are 237 (2.50), 287 (2.09), and 200 (2.81). The difference between the two subgroups is statistically insignificant. The excretion increases slightly with age; the correlation coefficient of the linear relationship is statistically significant. The day-to-day fluctuations in the excretion of both Th and U are considerable. (P.A.)

  11. Zeeman atomic absorption spectrometry

    The design and development of a Zeeman atomic absorption spectrometer for trace element analysis are described. An instruction manual is included which details the operation, adjustment, and maintenance. Specifications and circuit diagrams are given

  12. Late excretion rates of 226Ra and 210Pb following occupational or iatrogenic exposure. I. 226Ra

    The urinary and fecal excretion rates of 226Ra have been determined for 53 subjects who had been exposed to 226Ra; 25 had been radium dial painters, 16 were iatrogenic (medical) cases and 12 were former radium chemists. The mean coefficient of elimination, CE (fraction of body content excreted annually), was significantly lower for the medical cases than for dial painters. The mean ratio of urinary-to-fecal excretion rates was 3.0 +- 0.7%

  13. Renal ammonia excretion in response to hypokalemia: effect of collecting duct-specific Rh C glycoprotein deletion

    Lee, Hyun-Wook; Verlander, Jill W.; Bishop, Jesse M.; Handlogten, Mary E.; Han, Ki-Hwan; Weiner, I. David

    2012-01-01

    The Rhesus factor protein, Rh C glycoprotein (Rhcg), is an ammonia transporter whose expression in the collecting duct is necessary for normal ammonia excretion both in basal conditions and in response to metabolic acidosis. Hypokalemia is a common clinical condition associated with increased renal ammonia excretion. In contrast to basal conditions and metabolic acidosis, increased ammonia excretion during hypokalemia can lead to an acid-base disorder, metabolic alkalosis, rather than mainten...

  14. Assessment of fetal exposure risk following seminal excretion of a therapeutic IgG4 (T-IgG4) monoclonal antibody using a rabbit model.

    Breslin, William J; Hilbish, Kim G; Page, Todd J; Coutant, David E

    2014-09-01

    Studies were conducted in New Zealand White rabbits to assess the seminal transfer, vaginal absorption, and placental transfer of a therapeutic monoclonal antibody (T-IgG4). T-IgG4 was administered by intravenous injection (IV) in males and by IV and intravaginal routes in females. Low levels of T-IgG4 were excreted into seminal plasma (100- to 370-fold lower than serum concentrations) and absorbed following vaginal dosing (three orders of magnitude lower than IV administration). On gestation day 29 (GD29), fetal serum T-IgG4 levels were 1.5-fold greater than maternal levels following IV dosing. The fetal T-IgG4 exposure ratio for seminal transfer vs. direct maternal IV dosing was estimated to be 1.3×10(-8). Applying human serum T-IgG4 exposure data to the model, the estimated human T-IgG4 serum concentration from seminal transfer was 3.07×10(-7)μg/mL, an exposure level at least 1000-fold lower than the T-IgG4-ligand dissociation constant (Kd) and at least seven orders of magnitude lower than the in vivo concentration producing 20% inhibition of the target (EC20). These data indicate that excretion of a T-IgG4 into semen would not result in a biologically meaningful exposure risk to the conceptus of an untreated partner. PMID:24863471

  15. Chemical forms of calcium in CA,Zn- and Ca,Cd-containing grains excreted by tobacco trichomes

    Sarret, G.; Isaure, M.-P. [Environmental Geochemistry Group, LGIT, Univ. of Grenoble and CNRS, Grenoble cedex 9 (France)], E-mail: geraldine.sarret@ujf-grenoble.fr; Marcus, M.A. [Advanced Light Source (ALS), Lawrence Berkeley National Lab, Berkeley, California (United States); Harada, E. [Environmental Geochemistry Group, LGIT, Univ. of Grenoble and CNRS, Grenoble cedex 9 (France); Div. of Forest Resources, College of Forest Sciences, Kangwon National Univ., Chunchon, Kangwon-do (Korea, Republic of); Choi, Y.-E. [Div. of Forest Resources, College of Forest Sciences, Kangwon National Univ., Kangwon-do (Korea, Republic of); Pairis, S. [Inst. Neel CNRS-UJF, Dept. Matiere Condensee, Materiaux et Fonctions, Pole Instrumentation (Microscopie Electronique), Grenoble cedex 9 (France); Fakra, S. [Advanced Light Source (ALS), Lawrence Berkeley National Lab, Berkeley, California (United States); Manceau, A. [Environmental Geochemistry Group, LGIT, Univ. of Grenoble and CNRS, Grenoble cedex 9 (France)

    2007-10-15

    Tobacco (Nicotiana tabacum L. cv. Xanthi) plants exposed to toxic levels of zinc and cadmium excrete metals through their leaf trichomes (epidermal hairs) as Zn,Ca- and Cd,Ca-containing grains. Little is known about the nature and formation mechanism of these precipitates. The chemical, crystalline, and noncrystalline compositions of individual grains produced by tobacco were studied by scanning electron microscopy coupled with energy dispersive X-ray analysis (SEM-EDX), micro-X-ray diffraction ({mu}XRD), and calcium K-edge micro X-ray absorption near edge structure ({mu}XANES) spectroscopy. Zinc is predominantly incorporated in calcite and cadmium in calcite and vaterite. Aragonite, which occurs occasionally, does not seem to contain trace metals. In addition to being precipitated in its three possible polymorphic forms, calcite, aragonite, and vaterite, calcium is also speciated as amorphous CaCO{sub 3} and possibly organic Ca in some grains. Most often, a particular grain consists of two or more crystalline and noncrystalline phases. The observed variability of intra- and inter-grain elemental and phase composition suggests that this biomineralization process is not constrained by biological factors but instead results from thermodynamically and kinetically controlled reactions. This study illustrates the potential of laterally resolved X-ray synchrotron radiation techniques ({mu}XRD and {mu}XANES) to study biomineralization and metal immobilization processes in plants. (author)

  16. The excretion of isotope in urea and ammonia for estimating protein turnover in man with [15N]glycine

    Four normal adults were given [15N]-glycine in a single dose either orally or intravenously. Rates of whole-body protein turnover were estimated from the excretion of 15N in ammonia and in urea during the following 9 h. The rate derived from urea took account of the [15N]urea retained in body water. In postabsorptive subjects the rates of protein synthesis given by ammonia were equal to those from urea, when the isotope was given orally, but lower when an intravenous dose was given. In subjects receiving equal portions of food every 2 h rates of synthesis calculated from ammonia were much lower than those from urea whether an oral or intravenous isotope was given. Comparison of rates obtained during the postabsorptive and absorptive periods indicated regulation by food intake primarily of synthesis when measurements were made on urea, but regulation primarily of breakdown when measurements were made on ammonia. These inconsistencies suggest that changes in protein metabolism might be assessed better by correlating results given by different end-products, and it is suggested that the mean value given by urea and ammonia will be useful for this purpose. (author)

  17. Chemical forms of calcium in CA,Zn- and Ca,Cd-containing grains excreted by tobacco trichomes

    Tobacco (Nicotiana tabacum L. cv. Xanthi) plants exposed to toxic levels of zinc and cadmium excrete metals through their leaf trichomes (epidermal hairs) as Zn,Ca- and Cd,Ca-containing grains. Little is known about the nature and formation mechanism of these precipitates. The chemical, crystalline, and noncrystalline compositions of individual grains produced by tobacco were studied by scanning electron microscopy coupled with energy dispersive X-ray analysis (SEM-EDX), micro-X-ray diffraction (μXRD), and calcium K-edge micro X-ray absorption near edge structure (μXANES) spectroscopy. Zinc is predominantly incorporated in calcite and cadmium in calcite and vaterite. Aragonite, which occurs occasionally, does not seem to contain trace metals. In addition to being precipitated in its three possible polymorphic forms, calcite, aragonite, and vaterite, calcium is also speciated as amorphous CaCO3 and possibly organic Ca in some grains. Most often, a particular grain consists of two or more crystalline and noncrystalline phases. The observed variability of intra- and inter-grain elemental and phase composition suggests that this biomineralization process is not constrained by biological factors but instead results from thermodynamically and kinetically controlled reactions. This study illustrates the potential of laterally resolved X-ray synchrotron radiation techniques (μXRD and μXANES) to study biomineralization and metal immobilization processes in plants. (author)

  18. Benzene exposure assessed by metabolite excretion in Estonian oil shale mineworkers: influence of glutathione s-transferase polymorphisms

    Sørensen, Mette; Poole, Jason; Autrup, Herman;

    2004-01-01

    oil shale mine were compared with the excretion in workers engaged in various production assignments above ground. In addition, possible modifying effects of genetic polymorphisms in glutathione S-transferases T1 (GSTT1), M1 (GSTM1), and P1 (GSTP1) on the excretion of S-PMA and t,t-MA were......,t-MA and S-PMA excretion were significantly higher in smokers compared with nonsmokers. Subjects carrying the GSTT1 wild-type excreted higher concentrations of S-PMA than subjects carrying the null genotype, suggesting that it is a key enzyme in the glutathione conjugation that leads to S-PMA. The results...

  19. Effect of calcium from dairy and dietary supplements on faecal fat excretion: a meta-analysis of randomized controlled trials

    Christensen, R.; Lorenzen, Janne Kunchel; Svith, Carina Roholm;

    2009-01-01

    Observational studies have found that dietary calcium intake is inversely related to body weight and body fat mass. One explanatory mechanism is that dietary calcium increases faecal fat excretion. To examine the effect of calcium from dietary supplements or dairy products on quantitative faecal...... fat excretion, we performed a systematic review with meta-analysis. We included randomized, controlled trials of calcium (supplements or dairy) in healthy subjects, where faecal fat excretion was measured. Meta-analyses used random-effects models with changes in faecal fat excreted expressed as...

  20. Radiation Absorption Mechanism in Nonvolatile MNOS Structure

    2002-01-01

    The γ-ray radiation will speed up the discharge of the stored charge in nonvolatile MNOS structure. The radiation absorption mechanism to enhance the discharge is discussed. A direct radiation emission model from the interface traps distributing both in energy level and in space is given. The theoretical results based on this model are in good agreement with experimental measurement.

  1. Excretion of 131I by freshwater catfish (Ictalurus punctatus) and bluegill (Lepomis macrochirus)

    Fish in waters to which wastes from nuclear power stations are discharged accumulate radionuclides for a short time during batch discharges and then eliminate them during the longer intervals between discharges. Hence, the elimination rates of radionuclides are of importance in computing radiation doses to humans who eat fish caught in these waters. The excretion rates of 131I in two freshwater fish species were studied. Findings show that 131I is excreted quite rapidly by both species. 131I loss from fish muscle during deep frying was also measured and found to be 20 +- 4%. It is concluded that the practice of simply applying a concentration factor to convert the concentration in water to that in fish, without considering excretion, grossly overestimates the dose to the consumer, and that further studies should be made to identify other nuclides that behave similarly. (author)

  2. Excretion of Aflatoxin M1 in milk of goats fed diet contaminated by Aflatoxin B1

    Gianni Battacone

    2010-01-01

    Full Text Available An experiment was carried out to study the excretion of aflatoxin M1(AFM1 in milk of three goats fed a single dose (0.8mg/head of pure aflatoxin B1 (AFB1. The values of AFM1 concentration excreted in milk was highly variable among goats, even if the pattern of excretion over time was very similar among the three animals. AFM1 was first detected at the milking performed 1h after the AFB1 administration. The highest values of AFM1 concentration in milk were reached 3 and 6h after the AFB1 intake. The trend of clearance of AFM1 in milk over time was expressed by a decreasing exponential equation. AFM1 concentration was below the EU maximum allowed level (50 ng/L in milk collected 36 h after the AFB1 administration.

  3. Urinary estrogen excretion and concentration of serum human placental lactogen in pregnancies following legally induced abortion

    Obel, E B; Madsen, Mette

    1980-01-01

    Feto-placental function was assessed by 24-hour excretion of estrogen in urine and by the concentration of human Placental Lactogen (hPL) in serum in pregnant women whose previous pregnancy was terminated by legally induced abortion. The mean 24-hour excretion of estrogens in urine and the mean...... increased frequency of dysfunction of the feto-placental unit during the last part of pregnancy in women with previous legally induced abortion. These findings indicate that legal abortion does not seem to increase the frequency of retarded intrauterine growth in a subsequent pregnancy....... concentration of hPL in serum were no lower in this group than in women without previous induced abortion. Neither was the frequency of a low 24-hour excretion of estrogens in urine or low concentration of hPL in serum (values less than mean - 1.96 s) found to be increased. This study could not demonstrate an...

  4. Interaction between the renal excretion rates of beta 2-microglobulin and tobramycin in man.

    Vree, T B; Zweens, K; Huige, P J; Guelen, P J; Jongman-Nix, B

    1984-03-27

    The renal excretion rate of beta 2-microglobulin in man is 127 +/- 98 ng/min at alkaline urine pH (pH 7). Tobramycin, up to intravenous doses of 160 mg (2 mg/kg) does not increase the renal excretion rate of beta 2-microglobulin. Tobramycin must have less affinity than gentamicin for the tubular system for active reabsorption of amino groups containing organic compounds. Due to this reduced affinity tobramycin will be absorbed less by the proximal tubular cells, which may be one of the reasons for tobramycin being less toxic than gentamicin. beta 2-Microglobulin excretion can be used as a parameter for the relative binding affinity of aminoglycosides. PMID:6370509

  5. Urinary excretion of biomarkers of oxidatively damaged DNA and RNA in hereditary hemochromatosis

    Broedbaek, Kasper; Poulsen, Henrik E; Weimann, Allan; Kom, Ghainsom D; Schwedhelm, Edzard; Nielsen, Peter; Böger, Rainer H

    2009-01-01

    after phlebotomy treatment the excretion of the RNA oxidation product 8-oxoGuo returned to control values and the excretion of the DNA product 8-oxo-7,8-dihydro-2'-deoxyguanosine was reduced by 30%. In patients with hereditary hemochromatosis oxidative stress on nucleic acids is an important feature of......Oxidatively generated damage to nucleic acids is considered to play a significant role in carcinogenesis, and it has been shown that people with hereditary hemochromatosis are at increased risk of cancer. In this study we used a new refined liquid chromatography-tandem mass spectrometry method to...... measure the urinary excretion of oxidatively generated 8-oxo-7,8-dihydroguanine and related 2'-deoxyribonucleoside and ribonucleoside derivatives in hereditary hemochromatosis patients, and we investigated the effect of treatment on the levels of these modifications. The study was carried out as a...

  6. Nitrogen excretion in rats on a protein-free diet and during starvation

    Chwalibog, André; Sawosz, Ewa; Niemiec, Tomasz;

    2008-01-01

    Nitrogen balances (six days) were determined in male Wistar rats during feeding a diet with sufficient protein or a nearly protein-free diet (n = 2 x 24), and then during three days of starvation (n = 2 x 12). The objective was to evaluate the effect of protein withdrawal on minimum nitrogen...... excretion in urine (UN), corresponding to endogenous UN, during feeding and subsequent starvation periods. The rats fed the protein free-diet had almost the same excretion of urinary N during feeding and starvation (165 and 157 mg/kg W(0.75)), while it was 444 mg/kg W(0.75) in rats previously fed with...... protein, demonstrating a major influence of protein content in a diet on N excretion during starvation. Consequently, the impact of former protein supply on N losses during starvation ought to be considered when evaluating minimum N requirement necessary to sustain life....

  7. Excretion of purine base derivatives after intake of bacterial protein meal in pigs

    Hellwing, Anne Louise Frydendahl; Tauson, Anne-Helene; Skrede, A.

    2007-01-01

    Bacterial protein meal has a high content ofprotein but also of RNA and DNA. Sixteen barrows were allocated to four diets containing increasing levels of bacterial protein meal (BPM), from weaning to 80 kg live weight, to evaluate whether the RNA and DNA contents of BPM influenced the retention...... of nitrogen. It was hypothesised that an increased intake of RNA and DNA would lead to an increased urinary excretion of purine base derivatives and increased plasma concentrations. Retention of nitrogen was unaffected by dietary content of BPM (P=0.08) and the urinary excretion of purine base derivatives...... increased with increasing dietary content of BPM. No differences in fasting plasma concentration of uric acid, xanthine and hypoxanthine were observed. It can therefore be concluded that increasing levels of dietary BPM maintained protein accretion and led to changes in excretion of purine detrivatices...

  8. Effect of 14 days of bed rest on urine metabolite excretion and plasma enzyme levels

    Pace, N.; Grunbaum, B. W.; Kodama, A. M.; Rahlmann, D. F.; Newsom, B. D.

    1974-01-01

    After 1 week of ambulatory base-line measurement, a group of 8 men 19-26 years of age remained continuously recumbent for 14 days. Studies were continued for 1 week following the prolonged recumbency. Urine excretion rates for a number of constituents were determined 2 days before bed rest, on day 14 of bed rest, and day 6 after bed rest. Blood plasma samples were also obtained at these times, and analyzed for several enzymes. On day 14 of bed rest significant increases were observed in urine excretion of total osmotically-active substances, magnesium, calcium, phosphate, creatinine, hydroxyproline, and 17-OH corticosteroids. A decrease occurred in urinary glucose excretion. Plasma levels of alkaline phosphatase and LDH-3 were depressed, while plasma GPT was elevated. Many of these changes persisted on day 6 after bed rest, and are interpreted as concomitants of the disuse atrophy of the musculoskeletal system that characterizes prolonged bed rest and weightlessness.

  9. Effect of fruit juice intake on urinary quercetin excretion and biomarkers of antioxidative status

    Young, J. F.; Nielsen, S. E.; Haraldsdottir, J.;

    1999-01-01

    Background: Epidemiologic studies suggest that foods rich in flavonoids might reduce the risk of cardiovascular disease. Objective: Our objective was to investigate the effect of intake of flavonoid-containing black currant and apple juice on urinary excretion of quercetin and on markers of...... oxidative status. Design: This was a crossover study with 3 doses of juice (750, 1000, and 1500 mL) consumed for 1 wk by 4 women and 1 man corresponding to an intake of 4.8, 6.4, and 9.6 mg quercetin/d. Results: Urinary excretion of quercetin increased significantly with dose and with time. The fraction...... excreted in urine was 0.29-0.47%. Plasma quercetin did not change with juice inter vention, Plasma ascorbate increased during intervention because of the ascorbate in the juice. Total plasma malondialdehyde decreased with time during the 1500-mL juice intervention, indicating reduced lipid oxidation in...

  10. Urinary albumin excretion rate and cardiovascular disease in Spaniard type 2 diabetic patients.

    Relimpio, F; Pumar, A; Losada, F; Molina, J; Maynar, A; Acosta, D; Astorga, R

    1997-05-01

    To assess the prevalence of urinary albumin excretion abnormalities and their associations with cardiovascular disease or its classical risk factors in type 2 diabetes mellitus, 1348 clinic-proceeding patients have been studied retrospectively. The overnight urinary albumin excretion rate, blood pressure, smoking, ophthalmic and cardiovascular status, current therapies, estimates of glycemic control, plasma lipids, serum creatinine and uric acid have been ascertained. 767 (56.8%) patients were found normoalbuminuric, 461 (34.1%) microalbuminuric and 120 (8.9%) macroalbuminuric. In bivariate analyses, the urinary albumin excretion rate had statistically significant (P creatinine, uric acid, triglycerides, high density lipoprotein (HDL)-cholesterol and apolipoprotein B. Borderline statistically significant (P creatinine, HbA1c, male sex and hypertension were sequentially selected as independently associated with macroalbuminuria. Micro and macroalbuminuria are frequent abnormalities associated with poorly controlled and complicated disease, with overt cardiovascular disease and its classical risk factors as well as with the male sex. PMID:9229197

  11. Impaired left-ventricular function in insulin-dependent diabetic patients with increased urinary albumin excretion

    Kelbaek, H; Jensen, T; Feldt-Rasmussen, B; Christensen, N J; Richter, E A; Deckert, T; Nielsen, S L

    1991-01-01

    Cardiac function was studied in 30 patients with insulin-dependent diabetes mellitus. Three groups, matched for age and diabetes duration, were defined as: group I (n = 10), normal urinary albumin excretion less than 30 mg 24 h-1; group II (n = 10), incipient diabetic nephropathy (urinary albumin...... excretion in the range of 30-300 mg 24 h-1); and group III (n = 10), clinical diabetic nephropathy (urinary albumin excretion greater than 300 mg 24 h-1). Ten non-diabetic subjects matched for sex and age served as controls. The left-ventricular end-diastolic volume measured by radionuclide cardiography was......, at rest and during exercise, lower in group II and III compared with controls (p less than 0.05), while intermediate values were found in group I. The cardiac output was similar in the control group and group I; it was reduced, but not significantly so (p = 0.10), in group III and was significantly...

  12. Seven-effect absorption refrigeration

    DeVault, Robert C.; Biermann, Wendell J.

    1989-01-01

    A seven-effect absorption refrigeration cycle is disclosed utilizing three absorption circuits. In addition, a heat exchanger is used for heating the generator of the low absorption circuit with heat rejected from the condenser and absorber of the medium absorption circuit. A heat exchanger is also provided for heating the generator of the medium absorption circuit with heat rejected from the condenser and absorber of the high absorption circuit. If desired, another heat exchanger can also be provided for heating the evaporator of the high absorption circuit with rejected heat from either the condenser or absorber of the low absorption circuit.

  13. Percutaneous absorption of triclocarban in rat and man.

    Howes, D; Black, J G

    1976-06-01

    The route and rate of excretion by rats of the germicide (1 4 C) Triclocarban formerly called trichlorocarbanilide, given by parenteral injection has been investigated. Blood levels based on radioactivity and by chemical determination after parenteral injection have been compared with those obtained after topical application of (1 4 C) Triclocarban in soaps and in dimethylformamide (DMF) through occluded rat skin has been studied. Other soaps and a hand cleanser containing (1 4 C) Triclocarban have been applied to rat skin without occlusion and the effects of duration of contact, concentration and the use of a solubilizer have been investigated. In humans, absorption of Triclocarban through skin after bathing daily for 28 days has been investigated by chemical analysis of blood and urine. The data show that elimination by the rat is rapid and complete principally via the faeces. Blood levels after parenteral injection are low and comparison of the radioactivity and chemical determinations suggest rapid metabolism of the Triclocarban. After application to the skin, blood levels based on 1 4 C are very low. Absorption of (1 4 C) Triclocarban through occluded rat skin was greater from DMF than from soaps. With non-occluded rat skin, absorption from soaps was less and was dependent on concentration but independent of duration of contact. The use of a solubilizer did not increase absorption through skin. No measurable Triclocarban (less than 25 ppb) was present in blood and urine samples of volunteers during or shortly after a 28-day intensive bathing regimen. PMID:941165

  14. Absorption spectra of quasars and the structure of the Universe

    The analysis of the distribution of the distances between the systems of absorption lines in the quasars' spectra and the comparison of this distribution with the distribution of the distances between superclusters in the deep optical surveys are carried out. It is shown that the systems of absorption lines are connected with superclusters of galaxies. The comparison of the absorbing gas parameters with the data for coronae of the Galaxy and of the Magellanic Clouds confirms this connection and permits to revise conclusions of the theory on the properties of superclusters. The problem of unidentified absorption lines in the quasars spectra is discussed

  15. 棕榈酸在三酰甘油中的位置分布对大鼠营养吸收的影响%Effect of positional distribution of palmitic acid in triglycerides on the absorption of the nutrition in rats

    宋秋; 刘亚东; 李晓敏; 杨丽杰

    2012-01-01

    The impacts of the position of palmitic acid in triglyceride on the absorption of fatty acids and mineral were studied. Feeding experiment was performed by using four groups of young male Wistar rats. Fat raw materials with different proportions of sn-2 position palmitic acid were added into fat-free diets which were the OPO ( 1,3- dioleoyl- 2- palmitoyl triglyceride ) structural fat, the vegetable oil mixture with imitating the composition of OPO,the infant formula containing OPO and the common infant formula. The proportions of the experimental fat in each groups were all 10% ,as for the sn-2 position palmitic acid in four groups were respectively 45.40% ,13.29% ,48.04% ,and 28.66%. After 2 weeks feeding,the contents of lipid,calcium and magnesium in the fecal were analyzed. The results showed that the fat absorption after intake of OPO and the infant formula containing OPO were higher than the other two groups significantly with much less calcium excreting. In conclusion,high content of sn-2 position palmitic acid could promote the absorption of fat in rats, reduce the formation of fatty acid soap and improve the calcium absorption.%研究了棕榈酸在三酰甘油中的不同位置分布对脂肪酸及矿质元素吸收的影响。以幼龄雄性Wistar大鼠为动物模型,将含不同比例sn-2位棕榈酸的脂肪原料添加到无脂饲料中,分别为:OPO(1,3-二油酸-2-棕榈酸甘油酯)结构脂肪,组成模拟OPO的混合植物油,含OPO的婴儿配方奶粉以及常规婴儿配方奶粉。饲料实验脂肪含量均为10%,各组sn-2位棕榈酸相对含量分别为45.40%、13.29%、48.04%、28.66%。喂养两周后,分析大鼠粪便中的脂质及钙、镁元素。结果显示,OPO组和OPO婴儿配方奶粉组的大鼠对脂肪的吸收显著高于另外两组,并且钙排泄较少。由此可得出结论:高含量的sn-2位棕榈酸可以促进大鼠对脂肪的吸收,减少脂肪酸皂的形成,并能改善对钙的吸收。

  16. Percutaneous absorption of tritium-gas-contaminated pump oil

    Trivedi, A. [Radiation Biology and Health Physics Branch, Ontario (Canada)

    1995-08-01

    One of the radiological problems encountered in tritium handling facilities is the hazards associated with tritium`s ability to label and degrade organic materials. Experiments in which male hairless rats have been contaminated with tritium-gas-contaminated pump oil have demonstrated that tritium deposited on the skin provides an input of organically bound tritium and tritiated water in the body. The accumulation of organically bound tritium at the point of contact in the skin and in various tissues influenced tritium excretion in urine and feces. The retention of tritium in the body showed that tritium was mainly metabolized and assimilated as organically bound tritium. The distribution of tritiated water was rapid and uniform in the whole-body. Analyses of tritium excreted in animal urine and feces showed that a significant level of organically bound tritium was excreted shortly after exposure. The highest concentration of tritium activity was measured in the exposed area of the skin. An increased level of tritium accumulation in the liver and kidneys was seen. Dose calculations showed that the exposed skin had the highest dose, and the skin dose was primarily due to the retention of organically bound tritium at the point of contact. The interpretation of these data has indicated that the retention of short-term organically bound tritium in the skin may be a dominant factor for dosimetry purposes. 19 refs., 5 figs., 4 tabs.

  17. Percutaneous absorption of tritium-gas-contaminated pump oil

    Trivedi, A

    1995-07-01

    One of the radiological problems encountered in tritium handling facilities is the hazards associated with tritium's ability to label and degrade organic materials. Experiments in which male hairless rats have been contaminated with tritium-gas-contaminated pump oil have demonstrated that tritium deposited on the skin provides an input of organically bound tritium and tritiated water in the body. The accumulation of organically bound tritium at the point of contact in the skin and in various tissues influenced tritium excretion in urine and feces. The retention of tritium in the body showed that tritium was mainly metabolized and assimilated as organically bound tritium. The distribution of tritiated water was rapid and uniform in the whole-body. Analyses of tritium excreted in animal urine and feces showed that a significant level of organically bound tritium was excreted shortly after exposure. The highest concentration of tritium activity was measured in the exposed area of the skin. An increased level of tritium accumulation in the liver and kidneys was seen. Dose calculations showed that the exposed skin had the highest dose, and the skin dose was primarily due to the retention of organically bound tritium at the point of contact. The interpretation of these data has indicated that the retention of short-term organically bound tritium in the skin may be a dominant factor for dosimetry purposes. (author)

  18. Percutaneous absorption of tritium-gas-contaminated pump oil

    One of the radiological problems encountered in tritium handling facilities is the hazards associated with tritium's ability to label and degrade organic materials. Experiments in which male hairless rats have been contaminated with tritium-gas-contaminated pump oil have demonstrated that tritium deposited on the skin provides an input of organically bound tritium and tritiated water in the body. The accumulation of organically bound tritium at the point of contact in the skin and in various tissues influenced tritium excretion in urine and feces. The retention of tritium in the body showed that tritium was mainly metabolized and assimilated as organically bound tritium. The distribution of tritiated water was rapid and uniform in the whole-body. Analyses of tritium excreted in animal urine and feces showed that a significant level of organically bound tritium was excreted shortly after exposure. The highest concentration of tritium activity was measured in the exposed area of the skin. An increased level of tritium accumulation in the liver and kidneys was seen. Dose calculations showed that the exposed skin had the highest dose, and the skin dose was primarily due to the retention of organically bound tritium at the point of contact. The interpretation of these data has indicated that the retention of short-term organically bound tritium in the skin may be a dominant factor for dosimetry purposes. (author)

  19. Nitrogen excretion factors of livestock in the European Union: a review.

    Velthof, Gerard L; Hou, Yong; Oenema, Oene

    2015-12-01

    Livestock manures are major sources of nutrients, used for the fertilisation of cropland and grassland. Accurate estimates of the amounts of nutrients in livestock manures are required for nutrient management planning, but also for estimating nitrogen (N) budgets and emissions to the environment. Here we report on N excretion factors for a range of animal categories in policy reports by member states of the European Union (EU). Nitrogen excretion is defined in this paper as the total amount of N excreted by livestock per year as urine and faeces. We discuss the guidelines and methodologies for the estimation of N excretion factors by the EU Nitrates Directive, the OECD/Eurostat gross N balance guidebook, the EMEP/EEA Guidebook and the IPCC Guidelines. Our results show that N excretion factors for dairy cattle, other cattle, pigs, laying hens, broilers, sheep, and goats differ significantly between policy reports and between countries. Part of these differences may be related to differences in animal production (e.g. production of meat, milk and eggs), size/weight of the animals, and feed composition, but partly also to differences in the aggregation of livestock categories and estimation procedures. The methodologies and data used by member states are often not well described. There is a need for a common, harmonised methodology and procedure for the estimation of N excretion factors, to arrive at a common basis for the estimation of the production of manure N and N balances, and emissions of ammonia (NH3 ) and nitrous oxide (N2 O) across the EU. PMID:25959675

  20. Comparison of urinary iodine excretion in pregnant women with and without goiter and their newborns

    Setoodeh A

    1999-07-01

    Full Text Available Iodine availability for the maternal thyroid is reduced during pregnancy as a result of the loss of the nutrient by increased renal clearance, and competition by the fetoplacental unit. So with a marginal iodine intake, pregnancy constitutes a stimulus for both the maternal and fetal thyroids. On the other hand, iodine deficiency in the first trimester of pregnancy results in impaired development of the central nervous system, lack of T4 then results in smaller brain size associated with fewer neurons which are also shorter in length. This cross-sectional study was undertaken to evaluate pregnant women and their newborns, these two susceptible groups to IDD in an endemic area such as Shiraz. Urinary excretion of iodine as iodine (µg/dl/creatinine (gr ratios in two groups of pregnant women, one group without goiter (52.88% and the other with goiter (grade Ib and II 47.2% and their newborns were compared. There was no significant difference in urinary excretion of iodine in mothers and newborns of the 2 groups. In all newborns even in those of mothers excreting <50 mg iodine/gr creatinine, there was a significantly greater excretion of iodine probably due to increased renal clearance of iodine by the immature kidney, and their excretion of iodine was not parallel to those of mothers. There was no significant difference between weight, height and head circumference of the two groups of newborns. It is concluded that iodine excretion in neonates can not be used as an indicator of iodine deficiency disorder. In iodine deficient areas pregnancy justifies monitoring thyroid function and volume and therapeutic intervention to avoid hypothyroxinemia and goiterogenesis in both mother and newborn. Likewise neonatal thyroid screening constitutes a valuable and sensitive index for detecting the presence of iodine deficiency.

  1. The role of sphinter of Boyden in bile excretion and its regulating factors

    Jing Guo Wei; Yao Cheng Wang; Qing Jiang Meng

    2000-01-01

    AIM To investigate the role of sphincter of Boyden in bile excretion and its regulating factors.METHODS Perfusion manometry, choledocho-cineradiography, reaction of the sphincter of Boyden toendogenous cholecystokinin (CCK) and immunohistochemical quantitative analysis were performed in 16dogs to study the motility and morphology of the sphincter of Boyden in experimental (postcholecystectomy)group ( n = 8) and the control group (n = 8).RESULTS The bile duct surrounded by SB was a low-pressure lumen (10.0 ± 2.0 mmHg), in which thepressure was significantly different (P<0.01, t = 6. 195) from the basal pressure of the high-pressure area ofsphincter of Oddi (SO), its basal pressure (SOBP) was 16.9±0.5 mmHg. The SB was an enlarged ampulladuring bile excretion interval, and showed active contraction during bile excretion. Intrinsic CCK could causediastole of SO, but does not affect the systole and diastole of SB. After cholecystectomy, spastic contractionpersisted in SB, which could not be relieved by intrinsic CCK. The sensitivity to CCK of SO was decreased,and the evacuation time of media prolonged (27.0±3.4 min vs precholecystectomy 17.l±0.9min P<0.01,t =7.961). In immunohistochemistry analysis, the contents of a-actin, myosin in the SB of experimentalgroup showed no increase. Under electronic microscope, the main changes were 3D structuraldisarrangement of the cell framework, distortion of the microfilaments, swelling and aggregation ofmitochondria at the nuclear side.CONCLUSION The excretion of bile can be divided into two types, physiological bile excretion with a drivemainly caused by the contraction of SB, and the other, functional bile excretion with a drive mainly causedby the contraction of gallbladder. It seems that the function of SB was controlled by vagus, whereas SO wasmore sensitive to the intrinsic CCK, The intact gallbladder is an elemental factor of functional coordinationof SB and SO.

  2. Lead Excretion in Spanish Children with Autism Spectrum Disorder

    Milagros Fuentes-Albero

    2015-02-01

    Full Text Available Among epigenetic factors leading to increased prevalence of juvenile neuropsychiatric disorders, including autism spectrum disorder, exposure to metals, such as lead (Pb have led to conflicting results. The aim of the present study was to determine the levels of Pb in the urine of children with autism spectrum disorder (ASD compared with typically developing children (TD age- and sex-matched, and to analyze any association between core symptoms of ASD, special diets, supplements intake or prescription drugs and the concentration of Pb. The study was performed in a group of children with ASD (n = 35, average age 7.4 ± 0.5 years and TD (n = 34, average age 7.7 ± 0.9 years. Measurement of lead in urine was performed by atomic absorption spectrometry; symptoms of ASD were analyzed by diagnostic and statistical manual of mental disorders (DMS-IV using the questionnary ADI-R. Careful clinical evaluation was also undertaken and statistical analysis was done taking into account any possible confounding factor.

  3. Effects of the restriction of food and water intake on the distribution and retention of radioiodine in mice

    The effects of the restriction of food and water intakes on gastrointestinal absorption, distribution to organs and excretion of 131I were investigated in C3H/He mice. The animals were divided into four groups and administered orally 37 kBq carrier-free Na 131I in 0.25 ml normal saline. One group of animals was given food and water ad libitum throughout the experimental period. Food and water to the remaining groups were restricted before and/or after the administration of 131I. The animals in each group were sacrificed 4 h and 24 h after administration, and the activity of 131I in thyroid, blood, liver, kidney, gastrointestinal tract, urine, feces, and carcass was measured. There was a significant increase in the retention of 131I in the thyroid and the concentration of 131I in the blood due to the restriction of food and water after the administration of 131I. In contrast, a significant decrease in the urinary excretion was observed in these animals. In those animals, which fasted before administration only, the retention of 131I in the thyroid and other organs were decreased. Therefore, for an accurate diagnosis and effective therapy with radioiodine as well as effective radiation protection, the intake of food and water should be taken into account. (author)

  4. The Effect of Chlorothiazide on Caesium-137 Excretion in Human Subjects

    The present study was carried out to determine factors that influence caesium metabolism in normal human subjects with particular interest in finding a therapeutic regimen for reducing the body burden of caesium. Since caesium and potassium are chemically similar, and are both localized in the intracellular compartment of the body, principally in muscle, it seemed possible that chlorothiazide, which has a marked potassium diuretic effect, might also increase caesium excretion. Four normal subjects were given a single dose of 0.1 μc of caesium-137 by mouth. Two subjects were given chlorothiazide 2.0 g/d for a total of three consecutive days starting 1 h after the caesium intake. The chlorothiazide dose was repeated at two weeks. The other two subjects were used as controls. The body burden of caesium-137 was measured by a whole-body counter at intervals up to 320 d. Daily urine collections were made for three control days and 20 d following caesium intake. The samples were analysed for electrolytes and caesium activity. Although chlorothiazide increased K excretion to 1. 5 times the control values, it had no significant effect on caesium excretion or in reducing the body burden of caesium. In all subjects a small fraction of caesium (10-20%) was excreted rapidly with a biological half-life (T),) of less than 1 d. The remainder was excreted at a constant rate with Tb of 90 to 155 d. More than 70% of the caesium eliminated from the body per day was excreted by the kidney. Tb of K was also calculated by the formula TbK = Total body K/Urine K x 0,693 x 0,8 assuming 80% of the total potassium excreted is by kidney. Tb of K was 35 to 42 d. The discrimination ratio TbCs/TbK was 2.1 to 3.8. These results demonstrate that caesium and potassium are not utilized interchangeably. Caesium is retained preferentially over potassium and changes in potassium turnover have no effect on caesium turnover. Studies are being carried out at the present time to determine the effect of

  5. Beta-2-microglobulin excretion: an indicator of long term nephrotoxicity during cis-platinum treatment?

    Sørensen, P G; Nissen, Mogens Holst; Groth, S; Rørth, M

    1985-01-01

    To evaluate the value of beta-2-microglobulin as an indicator of acute and long-term cis-platinum-induced nephrotoxicity, 51Cr-EDTA clearance and serum concentration and urinary excretion of beta-2-microglobulin were measured in 18 patients treated with a regimen including cis-platinum. Before......-microglobulin remained unchanged. The decrease in 51Cr-EDTA clearance was not correlated to either the peak increase in the beta-2-microglobulin excretion or to the time of occurrence of the peak (R = 0.3). Thus, it is not possible to predict the long-term nephrotoxicity of cis-platinum by measuring the beta-2...

  6. Excretion pattern of aflatoxins in buffalo milk and carry-over in mozzarella cheese

    A. Gualla

    2011-03-01

    Full Text Available Some raw materials, used in animal feeding, can be contaminated by aflatoxins (AF. All the mammals that ingest AFB1, excrete small amounts of the hydroxylated metabolite aflatoxin M1 (AFM1 in their milk (Wood 1991. In the case of cow’s milk, the percentage excreted is 1-3% of that ingested (Veldman et al. 1992. AFM1 has been categorised as a class 2B, possible human carcinogen. AFM1 is associated with the protein fraction of milk and hence it is carried-over to cheese and to other milk products (Brackett and Marth, 1982....

  7. Impact of supervised cardiac rehabilitation on urinary albumin excretion in patients with cardiovascular disease.

    Kimura, Sahika; Ueda, Yuka; Ise, Takayuki; Yagi, Shusuke; Iwase, Takashi; Nishikawa, Koji; Yamaguchi, Koji; Yamada, Hirotsugu; Soeki, Takeshi; Wakatsuki, Tetsuzo; Katoh, Shinsuke; Akaike, Masashi; Yasui, Natsuo; Sata, Masataka

    2015-01-01

    Urinary albumin excretion is a predictor of cardiovascular death. Cardiac rehabilitation (CR) with exercise training (ET) has been shown to improve exercise capacity and prognosis in patients with cardiovascular disease (CVD). However, it remains unclear whether CR reduces urinary albumin excretion in CVD patients. We performed a retrospective, observational study using data obtained from 98 male CVD patients without macroalbuminuria and estimated glomerular filtration rate (eGFR) creatinine ratio (ACR) was significantly decreased in the supervised group at 6 months after enrollment (43 ± 71 mg/g to 17 ± 20 mg/g creatinine, P CVD and reduction in cardiovascular morbidity and mortality in CVD patients. PMID:25742947

  8. Estimating rumen microbial protein supply for indigenous ruminants using nuclear and purine excretion techniques in Indonesia

    The microbial protein supply to ruminants can be estimated based on the amount of purine derivatives (PD) excreted in the urine. Four experiments were conducted to evaluate the PD excretion method for Bali and Ongole cattle. In the first experiment, six male, two year old Bali cattle (Bos sondaicus) and six Ongole cattle (Bos indicus) of similar sex and age, were used to quantify the endogenous contribution to total PD excretion in the urine. In the second experiment, four cattle from each breed were used to examine the response of PD excretion to feed intake. 14C-uric acid was injected in one single dose to define the partitioning ratio of renal:non-renal losses of plasma PD. The third experiment was conducted to examine the ratio of purine N:total N in mixed rumen microbial population. The fourth experiment measured the enzyme activities of blood, liver and intestinal tissues concerned with PD metabolism. The results of the first experiment showed that endogenous PD excretion was 145 ± 42.0 and 132 ± 20.0 μmol/kg W0.75/d, for Bali and Ongole cattle, respectively. The second experiment indicated that the proportion of plasma PD excreted in the urine of Bali and Ongole cattle was 0.78 and 0.77 respectively. Hence, the prediction of purine absorbed based on PD excretion can be stated as Y = 0.78 X + 0.145 W0.75 and Y = 0.77 X + 0.132 W0.75 for Bali and Ongole cattle, respectively. The third experiment showed that there were no differences in the ratio of purine N:total N in mixed rumen microbes of Bali and Ongole cattle (17% vs 18%). The last experiment, showed that intestinal xanthine oxidase activity of Bali cattle was lower than that of Ongole cattle (0.001 vs 0.015 μmol uric acid produced/min/g tissue) but xanthine oxidase activity in the blood and liver of Bali cattle was higher than that of Ongole cattle (3.48 vs 1.34 μmol/min/L plasma and 0.191 vs 0.131 μmol/min/g liver tissue). Thus, there was no difference in PD excretion between these two breeds

  9. Effect of natural zeolite (clinoptilolite) on the excretion and deposition of radiostrontium in laboratory rats

    The effect of addition of the natural zeolite clinoptilolite to the diet on the excretion and deposition of 85Sr was examined in laboratory rats after a single peroral contamination. A significant increase in the total excreted activity and a decrease in the deposition of radiostrontium in the femur and tail vertebrae were observed on the administration of 5% or 10% zeolite. In time dependence measurements, the decontamination effect of the sorbent was only observed after its preventive administration. (author). 6 figs., 4 tabs

  10. Apparent gut excretion of Tc-99m-DISIDA in case of extrahepatic biliary atresia

    Patient had DISIDA scan at 39 days of age to exclude biliary atresia. Gut excretion was seen 18 h after injection and the diagnosis of neonatal hepatitis was made. Because of continued elevated liver function values, liver biopsy was performed and demonstrated findings consistent with biliary atresia. Exploratory laparotomy performed 8 days after the scan showed patient cystic duct, bule duct, and gall-bladder, but an atretic common hepatic duct. This case is an example of documented biliary atresia demonstrating gut excretion on the DISIDA scan. (orig.)

  11. Serum Level and 24hr. Excretion Pattern of Potassium Following the Intake of Combined Oral Contraceptives

    S. Kamyab

    1978-01-01

    Full Text Available Serum level and 24hr urinary excretion pattern of potassium have been studied in 104 healthy women, aged 18-44 years, using combined • oral contraceptives for a period of 3-48 months, and results h av e been compared with those obtained from 21 healthy controls of the same clinic. aged 19-40 years, using IUD. There was no sign ificant change observed in s erum potassium level, but 24hr urinary excretion pattern of potassium decreased significantly in 90% of the individuals equivalent to 2. &- 78 . 3% of the mean control, possibly due to a retention of potas sium in the cells.

  12. Ambulatory blood pressure and urinary albumin excretion in clinically healthy subjects

    Clausen, Peter Vilhelm; Jensen, J S; Borch-Johnsen, K;

    1998-01-01

    A slightly elevated urinary albumin excretion rate (UAER) is a predictor of atherosclerotic cardiovascular disease. The mechanism is unknown, but moderate office blood pressure elevation has been demonstrated as part of a clustering of known atherosclerotic risk factors in subjects with elevated...... increased urinary loss of albumin could not be solely related to the higher blood pressure. In conclusion, apparently healthy subjects with elevated UAER had slightly but significantly higher 24-hour systolic and diastolic blood pressure levels in addition to increased blood pressure loads but normal...... circadian variation. The demonstrated differences in blood pressure may offer a partial explanation for the association between elevated urinary albumin excretion and atherosclerotic cardiovascular risk....

  13. Variation of natural 232Th excretion in non-exposed persons

    Urinary excretion of 232Th was assessed in occupationally non-exposed persons by means of inductively coupled plasma-mass spectrometry (ICP-MS). Measurements were performed in 55 healthy subjects. Mean daily 232Th excretion was 47±26 μBq x d-1 (range 17-121 μBq x d-1). Results obtained showed no statistically significant correlation with age and no differences were found between males and females. The impact on the assessment of intakes by workers is discussed. (author)

  14. Regularity of nutrient absorption and distribution in different organs of Camellia oleifera at seedling stage%油茶苗期不同器官对各营养元素的吸收及养分间分配规律

    曹继钊; 唐健; 何应会; 覃其云; 宋贤冲

    2012-01-01

    In order to study nutrient absorption and distribution regularity in different organs of Camellia oleifera at seedling stage, the nutrient contents in 150 seedlings were determined and the correlation of distribution between different elements was analyzed. The results show that the N content is the highest, followed by K and Ca contents, Cu and B contents are the lowest. Absorption and distribution of N, P and K in leaves exists the relationship of mutual influence and promotion at seedling stage, but that in roots and stems has no significant correlation. Absorption and distribution of the nutrients exists an obvious regularity at seedling stage, so the new special fertilizer for C. oleifera at seedling stage can be developed based the regularity.%为了弄清油茶苗期不同器官对营养元素的吸收分配规律,对150株油茶苗期不同器官的营养元素含量进行了测定,分析了各营养元素之间分配的相关性.结果表明:N含量最高,K和Ca含量次之,Cu和B含量最低;油茶苗期叶片中主要营养元素N、P和K的吸收分配存在相互影响与相互促进的关系,而其根与茎中N、P和K的吸附分配没有显著的相关性.苗期的油茶对各营养元素的吸收分配存在明显的规律性,可以针对营养吸收分配规律开发新型油茶苗期专用肥.

  15. Vitamin A absorption

    Investigation of the absorption of vitamin A and related substances is complicated by the multiplicity of forms in which they occur in the diet and by the possibility that they may be subject to different mechanisms of absorption. Present knowledge of these mechanisms is inadequate, especially in the case of carotenoids. Numerous tests of absorption have been developed. The most common has been the biochemical measurement of the rise in plasma vitamin A after an oral dose of retinol or retinyl ester, but standardization is inadequate. Radioisotope tests based upon assay of serum or faecal activity following oral administration of tritiated vitamin A derivaties hold considerable promise, but again standardization is inadequate. From investigations hitherto performed it is known that absorption of vitamin A is influenced by several diseases, although as yet the consistency of results and the correlation with other tests of intestinal function have often been poor. However, the test of vitamin A absorption is nevertheless of clinical importance as a specialized measure of intestinal function. (author)

  16. Central cooling: absorptive chillers

    Christian, J.E.

    1977-08-01

    This technology evaluation covers commercially available single-effect, lithium-bromide absorption chillers ranging in nominal cooling capacities of 3 to 1,660 tons and double-effect lithium-bromide chillers from 385 to 1,060 tons. The nominal COP measured at operating conditions of 12 psig input steam for the single-effect machine, 85/sup 0/ entering condenser water, and 44/sup 0/F exiting chilled-water, ranges from 0.6 to 0.65. The nominal COP for the double-effect machine varies from 1.0 to 1.15 with 144 psig entering steam. Data are provided to estimate absorption-chiller performance at off-nominal operating conditions. The part-load performance curves along with cost estimating functions help the system design engineer select absorption equipment for a particular application based on life-cycle costs. Several suggestions are offered which may be useful for interfacing an absorption chiller with the remaining Integrated Community Energy System. The ammonia-water absorption chillers are not considered to be readily available technology for ICES application; therefore, performance and cost data on them are not included in this evaluation.

  17. Percutaneous absorption from soil.

    Andersen, Rosa Marie; Coman, Garrett; Blickenstaff, Nicholas R; Maibach, Howard I

    2014-01-01

    Abstract Some natural sites, as a result of contaminants emitted into the air and subsequently deposited in soil or accidental industrial release, have high levels of organic and non-organic chemicals in soil. In occupational and recreation settings, these could be potential sources of percutaneous exposure to humans. When investigating percutaneous absorption from soil - in vitro or vivo - soil load, particle size, layering, soil "age" time, along with the methods of performing the experiment and analyzing the results must be taken into consideration. Skin absorption from soil is generally reduced compared with uptake from water/acetone. However, the absorption of some compounds, e.g., pentachlorophenol, chlorodane and PCB 1254, are similar. Lipophilic compounds like dichlorodiphenyltrichloroethane, benzo[A]pyrene, and metals have the tendency to form reservoirs in skin. Thus, one should take caution in interpreting results directly from in vitro studies for risk assessment; in vivo validations are often required for the most relevant risk assessment. PMID:25205703

  18. Gastrointestinal absorption of neptunium in primates: effect of ingested mass, diet, and fasting

    Absorption and retention of neptunium were determined in baboons after intragastric administration of neptunium nitrate solutions at pH 1. The effects of mass, diet, and fasting on absorption were studied. At higher mass levels (400-800 micrograms Np/kg), absorption was about 1%; at lower mass intakes (0.0009-0.005 micrograms Np/kg), absorption was reduced by 10- to 20-fold. The addition of an oxidizing agent (Fe3+) increased gastrointestinal absorption and supported the hypothesis of a reduction of Np (V) when loss masses were ingested. Diets depleted of or enriched with hydroxy acids did not modify retention of neptunium but increased urinary excretion with increasing hydroxy acid content. The diet enriched with milk components reduced absorption by a factor of 5. Potatoes increased absorption and retention by a factor 5, not necessarily due to the effect of phytate. Fasting for 12 or 24 h increased retention and absorption by factors of about 3 and 10, respectively. Data obtained in baboons when low masses of neptunium were administered suggest that the f1 factor used by ICRP should be decreased. However, fasting as encountered in certain nutritional habits is a factor to be taken into consideration

  19. Revisiting Absorptive Capacity

    de Araújo, Ana Luiza Lara; Ulhøi, John Parm; Lettl, Christopher

    Absorptive capacity has mostly been perceived as a 'passive' outcome of R&D investments. Recently, however, a growing interest into its 'proactive' potentials has emerged. This paper taps into this development and proposes a dynamic model for conceptualizing the determinants of the complementary...... learning processes of absorptive capacity, which comprise combinative and adaptive capabilities. Drawing on survey data (n=169), the study concludes that combinative capabilities primarily enhance transformative and exploratory learning processes, while adaptive capabilities strengthen all three learning...... processes, with emphasis on exploitative learning. Before concluding, the paper addresses implications for theory and practice and limitations of this study....

  20. Effects of administration of potassium- and sodiumchlorides on faecal excretions and salivary and alimentary concentrations of, Na, K, 134Cs, Ca, Mg and P in reindeer fed a lichen diet

    Hans Staaland

    1998-02-01

    Full Text Available A comparison of the effects of administration of 350 mmol d-1 of KC1 or NaCl on faecal excretions, salivary concentrations and concentrations and pools of Na, K, 134Cs, Ca, Mg, P, and water in the alimentary tract of reindeer was carried out using three groups of three 10 months old reindeer fed a lichen diet. One group was used as a control group with no mineral supplementation. The level of K supplementation mimicked K intakes from summer pastures. NaCl was given at a rate which would mimic intake from salt licks by domestic ruminants of similar body size. Treatment with KC1 increased the salivary and alimentary concentrations and the alimentary pool sizes of K and faecal excretion of K increased. A decrease in l34Cs concentrations in all parts of the gastrointestinal tract indicated greater absorption of 134Cs during the KC1 treatment than in NaCl treated and control animals. Increased intake of Na or K had no significant effect on the digestibility of the lichen diet, but urine production increased. Little effects on pools or concentrations of Ca, Mg and P were observed. NaCl treatment increased urinary and faecal excretion of Na, but did not affect the metabolism of any of the other studied minerals.