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Sample records for 13co2 excretion tmax

  1. Field Measurements of Respiratory Del13CO2 and Photodegradation

    NASA Astrophysics Data System (ADS)

    van Asperen, H.; Sabbatini, S.; Nicolini, G.; Warneke, T.; Papale, D.; Notholt, J.

    2014-12-01

    Carbon decomposition dynamics have been studied in a variety of ecosystems and its variation can mostly be explained in terms of environmental variables (e.g. temperature and precipitation). However, carbon dynamics in arid, water limited regions have shown to be very different and are still largely unknown. Several studies have indicated the importance of photodegradation, the direct breakdown of organic matter by sunlight, in these arid regions. A FTIR (Fourier Transform Infrared Spectrometer) was set up to continuously measure concentrations of CO2, CH4, N2O, CO as well as del13C in CO2. The FTIR was connected to 2 different flux measurement systems: a Flux Gradient system and 2 flux chambers, providing a continuous data set of gas concentrations and biosphere-atmosphere gas fluxes at different heights and scales. Field measurements showed photodegradation induced carbon fluxes. Also, respiratory del13CO2 was determined by use of Keeling plots, and was determined to vary between -25‰ and -21‰. A clear diurnal pattern in respiratory del13CO2 was found, suggesting either different (dominant) respiratory processes between day and night or the effect of diffusive fractionation.

  2. The 13C-mixed triglyceride breath test in healthy adults: determinants of the 13CO2 response.

    PubMed

    Kalivianakis, M; Verkade, H J; Stellaard, F; van der Were, M; Elzinga, H; Vonk, R J

    1997-05-01

    Defects in lipolysis due to pancreatic insufficiency can be diagnosed by the mixed triglyceride (MTG) 13CO2 breath test. However, the effects of various test conditions on the 13CO2 response have only been partially elucidated. In healthy adults, we performed the 13CO2 mixed triglyceride breath test and we compared (a) the inter- and intra-individual variation in the 13CO2 response; (b) the effect of two different test meals; (c) the effect of an additional meal during the test; and (d) the effect of physical exercise during the test. Upon repeating the test in the same individual (test meal cream), repeatability coefficients were large, with respect to either time to maximum 13C excretion rate (3.8 h). maximum 13C excretion rate (4.9% 13C dose h-1) or cumulative recovery of 13C over the 9-h study period (22.7% 13C dose). The cumulative 13C expiration over 9 h obtained with the test meal composed of cream was quantitatively similar to that obtained with bread and butter: 42.2 +/- 8.4% and 47.7 +/- 6.3% respectively. Fasting for 9 h during the test resulted in similar 13C expiration rates and cumulative 13C expiration (43.4% +/- 7.2%) when compared with consumption of an additional meal 3 h after the start of the test (38.3 +/- 5.3%). The 13CO2 response increased in five out of seven subjects, but decreased in the other two, when moderate exercise was performed (bicycle ergometer, 50 W for 5 h). We conclude that the repeatability of the MTG test in healthy adults is low. The present results indicate that a solid and a liquid test meal, containing a similar amount of fats, give similar cumulative 13CO2 responses, and that stringent prolonged fasting during the test is unnecessary. Standardization of physical activity seems preferable, since the unequivocal effects of moderate exercise on the 13CO2 response were observed in the individuals studied. PMID:9179552

  3. Impact of oceanic circulation changes on atmospheric δ13CO2

    NASA Astrophysics Data System (ADS)

    Menviel, L.; Mouchet, A.; Meissner, K. J.; Joos, F.; England, M. H.

    2015-12-01

    δ13CO2 measured in Antarctic ice cores provides constraints on oceanic and terrestrial carbon cycle processes linked with millennial-scale and glacial/interglacial changes in atmospheric CO2. However, the interpretation of δ13CO2 is not straightforward. Using two Earth system models of intermediate complexity we perform a set of sensitivity experiments in which the formation rates of North Atlantic Deep Water (NADW), North Pacific Deep Water (NPDW), Antarctic Bottom Water (AABW) and Antarctic Intermediate Water (AAIW) are varied. We study the impact of these circulation changes on atmospheric δ13CO2 as well as on the oceanic δ13C distribution. In general, we find that the formation rates of AABW, NADW, NPDW and AAIW are negatively correlated with changes in δ13CO2: namely strong oceanic ventilation decreases atmospheric δ13CO2. However, since large scale ocean circulation reorganizations also impact nutrient utilization and the Earth's climate the relationship between atmospheric δ13CO2 levels and ocean ventilation rate is not unequivocal. In both models atmospheric δ13CO2 is very sensitive to changes in AABW formation rates: increased AABW formation enhances the upwelling of low δ13C waters to the surface and decreases atmospheric δ13CO2. By contrast, the impact of NADW changes on atmospheric δ13CO2 is less robust and might be model dependent.

  4. Impact of oceanic circulation changes on atmospheric δ13CO2

    NASA Astrophysics Data System (ADS)

    Menviel, L.; Mouchet, A.; Meissner, K. J.; Joos, F.; England, M. H.

    2015-11-01

    δ13CO2 measured in Antarctic ice cores provides constraints on oceanic and terrestrial carbon cycle processes linked with millennial-scale changes in atmospheric CO2. However, the interpretation of δ13CO2 is not straightforward. Using carbon isotope-enabled versions of the LOVECLIM and Bern3D models, we perform a set of sensitivity experiments in which the formation rates of North Atlantic Deep Water (NADW), North Pacific Deep Water (NPDW), Antarctic Bottom Water (AABW), and Antarctic Intermediate Water (AAIW) are varied. We study the impact of these circulation changes on atmospheric δ13CO2 as well as on the oceanic δ13C distribution. In general, we find that the formation rates of AABW, NADW, NPDW, and AAIW are negatively correlated with changes in δ13CO2: namely, strong oceanic ventilation decreases atmospheric δ13CO2. However, since large-scale oceanic circulation reorganizations also impact nutrient utilization and the Earth's climate, the relationship between atmospheric δ13CO2 levels and ocean ventilation rate is not unequivocal. In both models atmospheric δ13CO2 is very sensitive to changes in AABW formation rates: increased AABW formation enhances the transport of low δ13C waters to the surface and decreases atmospheric δ13CO2. By contrast, the impact of NADW changes on atmospheric δ13CO2 is less robust and might be model dependent. This results from complex interplay between global climate, carbon cycle, and the formation rate of NADW, a water body characterized by relatively high δ13C.

  5. Biosynthesis of Nudicaulins: A (13) CO2 -pulse/chase labeling study with Papaver nudicaule.

    PubMed

    Tatsis, Evangelos C; Eylert, Eva; Maddula, Ravi Kumar; Ostrozhenkova, Elena; Svatoš, Aleš; Eisenreich, Wolfgang; Schneider, Bernd

    2014-07-21

    Nudicaulins are unique alkaloids responsible for the yellow color of the petals of some papaveraceaous plants. To elucidate the unknown biosynthetic origin of the skeleton, a (13) CO2 -pulse/chase experiment was performed with growing Papaver nudicaule plants. (13) C NMR analysis revealed more than 20 multiple (13) C-enriched isotopologues in nudicaulins from the petals of (13) CO2 -labeled plants. The complex labeling pattern was compared with the isotopologue composition of a kaempferol derivative that was isolated from petals of the same (13) CO2 -labeled plants. The deconvolution of the labeling profiles indicated that the nudicaulin scaffold is assembled from products or intermediates of indole metabolism, the phenylpropanoid pathway, and the polyketide biosynthesis. Naringenin-type compounds and tryptophan/tryptamine are potential substrates for the condensation reaction finally generating the aglycone skeleton of nudicaulins.

  6. Measurements of substrate oxidation using (13)CO 2-breath testing reveals shifts in fuel mix during starvation.

    PubMed

    McCue, Marshall D; Pollock, Erik D

    2013-12-01

    Most fasting animals are believed to sequentially switch from predominantly utilizing one metabolic substrate to another from carbohydrates, to lipids, then to proteins. The timing of these physiological transitions has been estimated using measures of substrate oxidation including changes in respiratory exchange ratios, blood metabolites, nitrogen excretion, or enzyme activities in tissues. Here, we demonstrate how (13)CO2-breath testing can be used to partition among the oxidation of distinct nutrient pools in the body (i.e., carbohydrates, lipids, and proteins) that have become artificially enriched in (13)C. Seventy-two Swiss Webster mice were raised to adulthood on diets supplemented with (13)C-1-L-leucine, (13)C-1-palmitic acid, (13)C-1-D-glucose, or no tracer. Mice were then fasted for 72 h during which [Formula: see text], [Formula: see text], δ(13)C of exhaled CO2, body temperature, body mass, and blood metabolites (i.e., glucose, ketone bodies, and triacylglycerols) were measured. The fasting mice exhibited reductions in body mass (29 %), body temperature (3.3 °C), minimum observed metabolic rates (24 %), and respiratory exchange ratio (0.18), as well as significant changes in blood metabolites; but these responses were not particularly indicative of changes in oxidative fuel mixture. Measurements of endogenous nutrient oxidation by way of (13)CO2-breath testing revealed a decrease in the rate of oxidation of carbohydrates from 61 to 10 % of the total energy expenditure during the first 6 h without food. This response was mirrored by a coincidental increase in rate of endogenous lipid oxidation from 18 to 64 %. A transient peak in carbohydrate oxidation occurred between 8 and 14 h, presumably during increased glycogen mobilization. A well-defined period of protein sparing between 8 and 12 h was observed where endogenous protein oxidation accounted for as little as 8 % of the total energy expenditure. Thereafter, protein oxidation continually

  7. New ice core records on the glacial/interglacial change in atmospheric δ13CO2

    NASA Astrophysics Data System (ADS)

    Fischer, H.; Schmitt, J.; Schneider, R.; Elsig, J.; Lourantou, A.; Leuenberger, M.; Stocker, T. F.; Koehler, P.; Lavric, J.; Raynaud, D. P.; Chappellaz, J. A.

    2010-12-01

    The reconstruction of δ13CO2 using Antarctic ice cores promises a deeper understanding on the causes of past atmospheric CO2 changes. Previous measurements on the Taylor Dome ice core over the last 30,000 years (Smith et al., 1999) indicated marine processes to be dominating the significant δ13CO2 changes over the transition, whereas glacial δ13CO2 was only slightly depleted relative to the Holocene (Leuenberger et al., 1992; Smith et al., 1999). However, significant uncertainty and the low temporal resolution of the Taylor Dome δ13CO2 data prevented a more detailed interpretation. Recently, substantial improvements have been made in the analysis and the resolution of ice core δ13CO2 records (Elsig et al., 2009; Lourantou et al., 2010). With these and new measurements presented here, three independent δ13CO2 data sets over the last glacial/interglacial transition have now been derived from the two EPICA and the Talos Dome ice cores. Two of the methods use traditional dry extraction techniques with a reproducibility of 0.07-0.1‰. The third method uses a novel sublimation technique with a reproducibility of 0.05‰. Here we compare the data sets, their analytical setups and discuss their joint information as well as their differences. The three records provide a more detailed picture on the temporal evolution of δ13CO2 and confirm two pronounced isotope minima between 18-12,000 years BP in parallel to the two major phases of CO2 increase (Lourantou et al., 2010; Smith et al., 1999) as also reflected in marine sediments (Marchitto et al., 2007; Skinner et al., 2010). Accordingly, a release of old carbon from the deep ocean is most likely responsible for a large part of the long-term increase in atmospheric CO2 in this time interval. However, the fast CO2 jumps at a round 12,000 and 14,000 years BP may be partly of terrestrial origin (Elsig, 2009; Köhler et al., 2010b). The new sublimation data set provides also unambiguous δ13CO2 data for clathrate ice in

  8. Ecological and Molecular Study of Soil Chemoautotrophic Microorganisms via the Sequestration of Atmospheric 13CO2

    NASA Astrophysics Data System (ADS)

    Hart, K. M.; Kelleher, B.; Allen, C.; Simpson, A.

    2009-05-01

    Soil Organic Matter (SOM) is the most complicated biomaterial on Earth and stores significantly more carbon than is currently present in the atmosphere [1]. It has been recently reported that humic material in SOM is a highly complex mixture of microbial and plant biopolymers and not a distinct chemical fraction as previously thought [2]. Furthermore, it has been reported that the microbial biomass contribution to SOM is not comprised of mainly humic materials and that in fact the contribution to SOM by soil microorganisms has been seriously underestimated [3]. Therefore, the question arises if we underestimate microbial biomass in soil do we also underestimate carbon sequestration by soil microbes? Soil microorganisms consist of a large range of diverse species with soil bacteria contributing a large proportion of the biomass content. Autotrophs are organisms that can produce organic compounds from CO2 as the sole carbon source, using either light (photoautotroph) or inorganic reactions (chemoautotroph) as the energy source. The aim of this project is to enrich chemoautotrophic soil microbes with carbon-13 (13C) sequestered as 13CO2. Once labeled, these target microbes can be differentiated from other microbes using techniques such as Stable Isotope Probing (SIP) and carbon NMR. This enrichment is facilitated via incubation in a custom built environmental chamber and the controlled introduction of 13CO2. Before introduction of 13CO2 the chambers capabilities had to be fully characterized to ensure that it was fit for purpose. Mixed cultures of soil chemoautotrophic microorganisms were propagated from different soils and data collected using the environmental chamber demonstrated that CO2 fluctuations mimicked the natural activity of actively growing chemoautotrophic cultures. Therefore using this soil slurry approach, a mixed culture of soil autotrophs will be exposed to 13CO2 prior to the harvesting of the microbial biomass. Ion chromatographic analysis of the

  9. 13CO2 breath tests in non-invasive hepatological diagnosis

    PubMed Central

    Musialik, Joanna; Kasicka-Jonderko, Anna; Buschhaus, Magdalena

    2015-01-01

    In liver diagnostics, a simple, non-invasive test with high sensitivity and specificity is permanently being sought in order to assess the degree of liver damage. In addition to liver biopsy, algorithms using blood parameters or elastometry are used in clinical practice. However, these methods do not provide information about the true liver reserve, so the liver breath test seem to be a promising diagnostic tool. The basis of this test depends on the ability of particular hepatocyte enzyme systems to metabolise a tested substance labelled with a stable carbon isotope. The kinetics of 13CO2 elimination with expiratory air then permits quantitative assessment of the functional liver reserve and the degree of organ damage. In this paper the most commonly used tests, grouped according to the main metabolic pathways, are described. The usefulness of liver breath tests in specific clinical situations, both as a diagnostic and prognostic tool, is presented. PMID:25960807

  10. Tracing photosynthetic carbon in leaves with nanoSIMS after 13CO2 labelling

    NASA Astrophysics Data System (ADS)

    Dannoura, Masako; Takeuchi, Miyuki; Kominami, Yuji; Takanashi, Satoru; Kenichi, Yoshimura; Ataka, Mioko

    2015-04-01

    To understand the carbon allocation of the tree and forest ecosystem, it is important to consider the residence time of carbon in different pools at suitable time scales. For example the carbon used for respiration will stay a few minutes to a few days in the tree, the carbon used for storage or structure of leaves will stay months to years, and the carbon used for wood structure, it will stay over the whole lifespan of the tree. The leaves are the entrance of carbon in trees where it can be used for foliage growth and maintenance or exported to the other organs or the other forest ecosystem compartments. Tracing carbon isotope using NanoSIMS technique is one of useful methods to estimate where and how long the carbon stay in the tree organs. In this study, 13CO2 pulse labelling were conducted and 13C was measured by IRMS to see the amount of C remaining in the leaves with time.NanoSIMS was used to localize where the labelled C remained within the leaf tissue. Twice labelling were done on branches of Quercus serrata at FFPRI(Forest and Forest Products research Institute) in Kyoto, Japan. The first labelling was in 30 April 2012 when the leaves start flushing and the second one was in 29 May 2012 when the leaves were completely deployed. For both labelling experiment, one branch was selected and covered with transparent plastic bag. CO2 concentration was recorded with IRGA and air temperature inside the chamber was monitored. Then 13CO2 was injected into the bag, and after 1 hour, the bag was removed and the branch was again exposed to ambient air. Leaves were collected before and 10-12 times after labelling and their isotope compositions were measured by IRMS. The leaf collected just after labelling and 6 days after labelling were used for NanoSIMS observation. Samples for nanoSIMS were preserved in glutaraldehyde and then embed in epoxy resin. The sliced sample were placed on the silicon wafer and observed by NanoSIMS 50L(Cameca, France). The 13C was highest just

  11. Disequilibrium of 13CO2 fluxes between photosynthesis and respiration in North American temperate forest biomes

    NASA Astrophysics Data System (ADS)

    Lai, C.; Ehleringer, J.; Schauer, A.; Tans, P.; Hollinger, D.; Paw U, K.; Wofsy, S.

    2003-12-01

    We report the first weekly dataset of seasonal and interannual variability in δ 13C of CO2 fluxes from dominant forest ecosystems in the US. We observed large variations in the δ 13C of respired biosphere-atmosphere fluxes (δ 13CR) across 3 temperate coniferous and deciduous forest ecosystems (-24.9 +/- 0.4 to -31.3 +/- 0.6 per mil). Values of δ 13CR were significantly correlated with growing-season soil water availability. By analyzing daytime flask measurements collected at the top of canopies, we estimated an annual mean, flux-weighted δ 13C of net ecosystem CO2 exchange fluxes (δ 13Cnet). Combining δ 13CR and δ 13Cnet, along with eddy-covariance measured fluxes, we estimated regional discrimination against 13C during photosynthesis (Δ A) for these 3 forest ecosystems. Our approach allows for examination of the interannual correlations between gross primary production fluxes and Δ A that could potentially modulate atmospheric 13C budget. The results showed that C3 forests in temperate regions in the U.S. exhibited a slight isotopic disequilibrium (< 1 per mil) on an annual basis, despite significant seasonal variations in respired δ 13CO2 values (> 3 per mil). Such subtle isotopic disequilibrium however, when associated with enormous one-way gross fluxes, can effectively affect atmospheric 13C budget.

  12. 13C Tracking after 13CO2 Supply Revealed Diurnal Patterns of Wood Formation in Aspen.

    PubMed

    Mahboubi, Amir; Linden, Pernilla; Hedenström, Mattias; Moritz, Thomas; Niittylä, Totte

    2015-06-01

    Wood of trees is formed from carbon assimilated in the photosynthetic tissues. Determining the temporal dynamics of carbon assimilation, subsequent transport into developing wood, and incorporation to cell walls would further our understanding of wood formation in particular and tree growth in general. To investigate these questions, we designed a (13)CO2 labeling system to study carbon transport and incorporation to developing wood of hybrid aspen (Populus tremula × tremuloides). Tracking of (13)C incorporation to wood over a time course using nuclear magnetic resonance spectroscopy revealed diurnal patterns in wood cell wall biosynthesis. The dark period had a differential effect on (13)C incorporation to lignin and cell wall carbohydrates. No (13)C was incorporated into aromatic amino acids of cell wall proteins in the dark, suggesting that cell wall protein biosynthesis ceased during the night. The results show previously unrecognized temporal patterns in wood cell wall biosynthesis, suggest diurnal cycle as a possible cue in the regulation of carbon incorporation to wood, and establish a unique (13)C labeling method for the analysis of wood formation and secondary growth in trees.

  13. Terrestrial cycling of 13CO2 by photosynthesis, respiration, and biomass burning in SiBCASA

    NASA Astrophysics Data System (ADS)

    van der Velde, I. R.; Miller, J. B.; Schaefer, K.; van der Werf, G. R.; Krol, M. C.; Peters, W.

    2014-12-01

    We present an enhanced version of the SiBCASA terrestrial biosphere model that is extended with (a) biomass burning emissions from the SiBCASA carbon pools using remotely sensed burned area from the Global Fire Emissions Database (GFED), (b) an isotopic discrimination scheme that calculates 13C signatures of photosynthesis and autotrophic respiration, and (c) a separate set of 13C pools to carry isotope ratios into heterotrophic respiration. We quantify in this study the terrestrial exchange of CO2 and 13CO2 as a function of environmental changes in humidity and biomass burning. The implementation of biomass burning yields similar fluxes as CASA-GFED both in magnitude and spatial patterns. The implementation of isotope exchange gives a global mean discrimination value of 15.2‰, ranges between 4 and 20‰ depending on the photosynthetic pathway in the plant, and compares favorably (annually and seasonally) with other published values. Similarly, the isotopic disequilibrium is similar to other studies that include a small effect of biomass burning as it shortens the turnover of carbon. In comparison to measurements, a newly modified starch/sugar storage pool propagates the isotopic discrimination anomalies to respiration much better. In addition, the amplitude of the drought response by SiBCASA is lower than suggested by the measured isotope ratios. We show that a slight increase in the stomatal closure for large vapor pressure deficit would amplify the respired isotope ratio variability. Our study highlights the importance of isotope ratio observations of 13C to assess and improve biochemical models like SiBCASA, especially with regard to the allocation and turnover of carbon and the responses to drought.

  14. Decoding Biosynthetic Pathways in Plants by Pulse-Chase Strategies Using 13CO2 as a Universal Tracer †

    PubMed Central

    Bacher, Adelbert; Chen, Fan; Eisenreich, Wolfgang

    2016-01-01

    13CO2 pulse-chase experiments monitored by high-resolution NMR spectroscopy and mass spectrometry can provide 13C-isotopologue compositions in biosynthetic products. Experiments with a variety of plant species have documented that the isotopologue profiles generated with 13CO2 pulse-chase labeling are directly comparable to those that can be generated by the application of [U-13C6]glucose to aseptically growing plants. However, the application of the 13CO2 labeling technology is not subject to the experimental limitations that one has to take into account for experiments with [U-13C6]glucose and can be applied to plants growing under physiological conditions, even in the field. In practical terms, the results of biosynthetic studies with 13CO2 consist of the detection of pairs, triples and occasionally quadruples of 13C atoms that have been jointly contributed to the target metabolite, at an abundance that is well above the stochastic occurrence of such multiples. Notably, the connectivities of jointly transferred 13C multiples can have undergone modification by skeletal rearrangements that can be diagnosed from the isotopologue data. As shown by the examples presented in this review article, the approach turns out to be powerful in decoding the carbon topology of even complex biosynthetic pathways. PMID:27429012

  15. Constraining Ecosystem Gross Primary Production and Transpiration with Measurements of Photosynthetic 13CO2 Discrimination

    NASA Astrophysics Data System (ADS)

    Blonquist, J. M.; Wingate, L.; Ogeé, J.; Bowling, D. R.

    2011-12-01

    The stable carbon isotope composition of atmospheric CO2 (δ13Ca) can provide useful information on water use efficiency (WUE) dynamics of terrestrial ecosystems and potentially constrain models of CO2 and water fluxes at the land surface. This is due to the leaf-level relationship between photosynthetic 13CO2 discrimination (Δ), which influences δ13Ca, and the ratio of leaf intercellular to atmospheric CO2 mole fractions (Ci / Ca), which is related to WUE and is determined by the balance between C assimilation (CO2 demand) and stomatal conductance (CO2 supply). We used branch-scale Δ derived from tunable diode laser absorption spectroscopy measurements collected in a Maritime pine forest to estimate Ci / Ca variations over an entire growing season. We combined Ci / Ca estimates with rates of gross primary production (GPP) derived from eddy covariance (EC) to estimate canopy-scale stomatal conductance (Gs) and transpiration (T). Estimates of T were highly correlated to T estimates derived from sapflow data (y = 1.22x + 0.08; r2 = 0.61; slope P < 0.001) and T predictions from an ecosystem model (MuSICA) (y = 0.88x - 0.05; r2 = 0.64; slope P < 0.001). As an alternative to estimating T, Δ measurements can be used to estimate GPP by combining Ci / Ca estimates with Gs estimates from sapflow data. Estimates of GPP were determined in this fashion and were highly correlated to GPP values derived from EC (y = 0.82 + 0.07; r2 = 0.61; slope P < 0.001) and GPP predictions from MuSICA (y = 1.10 + 0.42; r2 = 0.50; slope P < 0.001). Results demonstrate that the leaf-level relationship between Δ and Ci / Ca can be extended to the canopy-scale and that Δ measurements have utility for partitioning ecosystem-scale CO2 and water fluxes.

  16. Method for tracing simulated CO2 leak in terrestrial environment with a 13CO2 tracer

    NASA Astrophysics Data System (ADS)

    Moni, Christophe; Rasse, Daniel

    2013-04-01

    Facilities for the geological storage of carbon dioxide (CO2) as part of carbon capture and storage (CCS) schemes will be designed to prevent any leakage from the defined 'storage complex'. However, developing regulations and guidance throughout the world (e.g. the EC Directive and the USEPA Vulnerability Evaluation Framework) recognize the importance of assessing the potential for environmental impacts from CO2 storage. RISCS, a European (FP7) project, aims to improve understanding of those impacts that could plausibly occur in the hypothetical case that unexpected leakage occurs. As part of the RISCS project the potential impacts that an unexpected CO2 leaks might have on a cropland ecosystems was investigated. A CO2 exposure field experiment based on CO2 injection at 85 cm depth under an oats culture was designed. To facilitate the characterization of the simulated leaking zone the gas used for injection was produced from natural gas and had a δ13C of -46‰. The aim of the present communication is to depict how the injected gas was traced within the soil-vegetation-atmosphere continuum using 13CO2 continuous cavity ring-down spectrometry (CRDS). Four subsurface experimental injection plots (6m x 3m) were set up. In order to test the effects of different intensity of leakage, the field experiment was designed as to create a longitudinal CO2 gradient for each plot. For this purpose gas supply pipes were inserted at one extremity of each plot at the base of a 45 cm thick layer of sand buried 40 cm below the surface under the clayey plough layer of Norwegian moraine soils. Soil CO2 concentration and isotopic signature were punctually recorded: 1) in the soil at 20 cm depth at 6 positions distributed on the central transect, 2) at the surface following a (50x50 cm) grid sampling pattern, and 3) in the canopy atmosphere at 10, 20, 30 cm along three longitudinal transects (seven sampling point per transect). Soil CO2 fluxes and isotopic signature were finally

  17. High-resolution δ13CO2 soil efflux monitoring in tree girdling experiment exposes large temporal variability

    NASA Astrophysics Data System (ADS)

    Egan, J. E.; Risk, D. A.; Nickerson, N. R.

    2011-12-01

    Carbon stable isotopes (δ13C) help us link above- and below-ground ecosystem processes, telling us about the temporal speed at which carbon cycles through plants to the soil and the amount of autotrophic respiration contributing to total soil respiration. In the past few years, we have seen rapid advances in the way we measure δ13CO2, using Tunable Diode Lasers (TDL) or Cavity Ring Down Spectroscopy (CRDS), which has helped make us aware of the high isotopic variability in natural soils. There is also growing recognition that most sampling strategies induce gas transport fractionations, which can be of high magnitude. Previous high profile studies using δ13CO2 are increasingly being called into question for these reasons, as variability or transport fractionations may have overprinted the biologic variability of interest. Our aim in this study was to conduct a girdling experiment similar to other widely cited girdling experiments, where we were interested in identifying isotopic signatures and magnitudes of respiration associated with autotrophic and heterotrophic activity, the temporal link between photosynthesis and respiration, and spatial variation within treatment plots. Our study is different from previous studies in that it relies on automated continuous CRDS measurements from several locations, using a sampling methodology that we developed specifically to address previous fractionation issues. The new methodology, called Isotopic-Forced Diffusion (Iso-FD), measures δ13CO2 efflux. It was tested in the lab and using models, and then implemented in the field for the tree girdling experiment in two 400-m2 pine plots in Antigonish County, NS, Canada. In addition to Iso-FD continuous data, spatial δ13CO2 data from gas chambers, and meteorological data were also collected in growing seasons of both 2010 and 2011. Variation was seen in bulk flux rates between the plots, and girdling both resulted in increased CO2 fluxes and decreased temporal variability in

  18. (13) CO2 /(12) CO2 exchange fluxes in a clamp-on leaf cuvette: disentangling artefacts and flux components.

    PubMed

    Gong, Xiao Ying; Schäufele, Rudi; Feneis, Wolfgang; Schnyder, Hans

    2015-11-01

    Leaks and isotopic disequilibria represent potential errors and artefacts during combined measurements of gas exchange and carbon isotope discrimination (Δ). This paper presents new protocols to quantify, minimize, and correct such phenomena. We performed experiments with gradients of CO2 concentration (up to ±250 μmol mol(-1) ) and δ(13) CCO2 (34‰), between a clamp-on leaf cuvette (LI-6400) and surrounding air, to assess (1) leak coefficients for CO2 , (12) CO2 , and (13) CO2 with the empty cuvette and with intact leaves of Holcus lanatus (C3 ) or Sorghum bicolor (C4 ) in the cuvette; and (2) isotopic disequilibria between net photosynthesis and dark respiration in light. Leak coefficients were virtually identical for (12) CO2 and (13) CO2 , but ∼8 times higher with leaves in the cuvette. Leaks generated errors on Δ up to 6‰ for H. lanatus and 2‰ for S. bicolor in full light; isotopic disequilibria produced similar variation of Δ. Leak errors in Δ in darkness were much larger due to small biological : leak flux ratios. Leak artefacts were fully corrected with leak coefficients determined on the same leaves as Δ measurements. Analysis of isotopic disequilibria enabled partitioning of net photosynthesis and dark respiration, and indicated inhibitions of dark respiration in full light (H. lanatus: 14%, S. bicolor: 58%).

  19. Repeat-pulse 13CO2 labeling of canola and field pea: implications for soil organic matter studies.

    PubMed

    Sangster, Amy; Knight, Diane; Farrell, Richard; Bedard-Haughn, Angela

    2010-10-15

    Both the quantity and quality of plant residues can impact soil properties and processes. Isotopic tracers can be used to trace plant residue decomposition if the tracer is homogeneously distributed throughout the plant. Continuous labeling will homogeneously label plants but is not widely accessible because elaborate equipment is needed. In order to determine if the more accessible repeat-pulse labeling method could be used to trace plant residue decomposition, this labeling procedure was employed using (13)CO(2) to enrich field pea and canola plants in a controlled environment. Plants were exposed weekly to pulses of 33 atom% (13)CO(2) and grown to maturity. The distribution of the label throughout the plant parts (roots, stem, leaves, and pod) and biochemical fractions (ADF and ADL) was determined. The label was not homogeneously distributed throughout the plant; in particular, the pod fractions were less enriched than other fractions indicating the importance of continuing labeling well into plant maturity for pod-producing plants. The ADL fraction was also less enriched than the ADF fraction. Because of the heterogeneity of the label throughout the plant, caution should be applied when using the repeat-pulse method to trace the fate of (13)C-labeled residues in the soil. However, root contributions to below-ground C were successfully determined from the repeat-pulse labeled root material, as was (13)C enrichment of soil within the top 15 cm. Canola contributed more above- and below-ground residue C than field pea; however, canola was also higher in ADF and ADL fractions indicating a more recalcitrant residue.

  20. Tracking the oxidative kinetics of carbohydrates, amino acids and fatty acids in the house sparrow using exhaled 13CO2.

    PubMed

    McCue, M D; Sivan, O; McWilliams, S R; Pinshow, B

    2010-03-01

    Clinicians commonly measure the (13)CO(2) in exhaled breath samples following administration of a metabolic tracer (breath testing) to diagnose certain infections and metabolic disorders. We believe that breath testing can become a powerful tool to investigate novel questions about the influence of ecological and physiological factors on the oxidative fates of exogenous nutrients. Here we examined several predictions regarding the oxidative kinetics of specific carbohydrates, amino acids and fatty acids in a dietary generalist, the house sparrow (Passer domesticus). After administering postprandial birds with 20 mg of one of seven (13)C-labeled tracers, we measured rates of (13)CO(2) production every 15 min over 2 h. We found that sparrows oxidized exogenous amino acids far more rapidly than carbohydrates or fatty acids, and that different tracers belonging to the same class of physiological fuels had unique oxidative kinetics. Glycine had a mean maximum rate of oxidation (2021 nmol min(-1)) that was significantly higher than that of leucine (351 nmol min(-1)), supporting our prediction that nonessential amino acids are oxidized more rapidly than essential amino acids. Exogenous glucose and fructose were oxidized to a similar extent (5.9% of dose), but the time required to reach maximum rates of oxidation was longer for fructose. The maximum rates of oxidation were significantly higher when exogenous glucose was administered as an aqueous solution (122 nmol min(-1)), rather than as an oil suspension (93 nmol min(-1)), supporting our prediction that exogenous lipids negatively influence rates of exogenous glucose oxidation. Dietary fatty acids had the lowest maximum rates of oxidation (2-6 nmol min(-1)), and differed significantly in the extent to which each was oxidized, with 0.73%, 0.63% and 0.21% of palmitic, oleic and stearic acid tracers oxidized, respectively.

  1. Unraveling carbohydrate transport mechanisms in young beech trees (Fagus sylvatica f. purpurea) by 13CO2 efflux measurements from stem and soil

    NASA Astrophysics Data System (ADS)

    Thoms, Ronny; Muhr, Jan; Keitel, Claudia; Kayler, Zachary; Gavrichkova, Olga; Köhler, Michael; Gessler, Arthur; Gleixner, Gerd

    2016-04-01

    Transport mechanisms of soluble carbohydrates and diurnal CO2 efflux from tree stems and surrounding soil are well studied. However, the effect of transport carbohydrates on respiration and their interaction with storage processes is largely unknown. Therefore, we performed a set of 13CO2 pulse labeling experiments on young trees of European beech (Fagus sylvatica f. purpurea). We labeled the whole tree crowns in a closed transparent plastic chamber with 99% 13CO2 for 30 min. In one experiment, only a single branch was labeled and removed 36 hours after labeling. In all experiments, we continuously measured the 13CO2 efflux from stem, branch and soil and sampled leaf and stem material every 3 h for 2 days, followed by a daily sampling of leaves in the successive 5 days. The compound specific δ 13C value of extracted soluble carbohydrates from leaf and stem material was measured by high-performance liquid chromatography linked with an isotope ratio mass spectrometer (HPLC-IRMS). The 13CO2 signal from soil respiration occurred only few hours after labeling indicating a very high transport rate of carbohydrates from leaf to roots and to the rhizosphere. The label was continuously depleted within the next 5 days. In contrast, we observed a remarkable oscillating pattern of 13CO2 efflux from the stem with maximum 13CO2 enrichment at noon and minima at night time. This oscillation suggests that enriched carbohydrates are respired during the day, whereas in the night the enriched sugars are not respired. The observed oscillation in stem 13CO2 enrichment remained unchanged even when only single branches were labelled and cut right afterwards. Thus, storage and conversion of carbohydrates only occurred within the stem. The δ13C patterns of extracted soluble carbohydrates showed, that a transformation of transitory starch to carbohydrates and vice versa was no driver of the oscillating 13CO2 efflux from the stem. Carbohydrates might have been transported in the phloem to

  2. Seasonal variations of belowground carbon transfer assessed by in situ 13CO2 pulse labelling of trees

    NASA Astrophysics Data System (ADS)

    Epron, D.; Ngao, J.; Dannoura, M.; Bakker, M. R.; Zeller, B.; Bazot, S.; Bosc, A.; Plain, C.; Lata, J. C.; Priault, P.; Barthes, L.; Loustau, D.

    2011-05-01

    Soil CO2 efflux is the main source of CO2 from forest ecosystems and it is tightly coupled to the transfer of recent photosynthetic assimilates belowground and their metabolism in roots, mycorrhiza and rhizosphere microorganisms feeding on root-derived exudates. The objective of our study was to assess patterns of belowground carbon allocation among tree species and along seasons. Pure 13CO2 pulse labelling of the entire crown of three different tree species (beech, oak and pine) was carried out at distinct phenological stages. Excess 13C in soil CO2 efflux was tracked using tuneable diode laser absorption spectrometry to determine time lags between the start of the labelling and the appearance of 13C in soil CO2 efflux and the amount of 13C allocated to soil CO2 efflux. Isotope composition (δ13C) of CO2 respired by fine roots and soil microbes was measured at several occasions after labelling, together with δ13C of bulk root tissue and microbial carbon. Time lags ranged from 0.5 to 1.3 days in beech and oak and were longer in pine (1.6-2.7 days during the active growing season, more than 4 days during the resting season), and the transfer of C to the microbial biomass was as fast as to the fine roots. The amount of 13C allocated to soil CO2 efflux was estimated from a compartment model. It varied between 1 and 21 % of the amount of 13CO2 taken up by the crown, depending on the species and the season. While rainfall exclusion that moderately decreased soil water content did not affect the pattern of carbon allocation to soil CO2 efflux in beech, seasonal patterns of carbon allocation belowground differed markedly between species, with pronounced seasonal variations in pine and beech. In beech, it may reflect competition with the strength of other sinks (aboveground growth in late spring and storage in late summer) that were not observed in oak. We report a fast transfer of recent photosynthates to the mycorhizosphere and we conclude that the patterns of carbon

  3. Evaluating the Community Land Model in a pine stand with 13CO2 labeling and shading manipulations

    NASA Astrophysics Data System (ADS)

    Mao, J.; Ricciuto, D. M.; Thornton, P. E.; Warren, J. M.; King, A. W.; Shi, X.; Iversen, C. M.; Norby, R. J.

    2015-05-01

    Carbon allocation and flow through ecosystems regulate land surface-atmosphere CO2 exchange and thus is a key, albeit uncertain, component of mechanistic models. The Partitioning in Trees and Soil (PiTS) experiment-model project tracked carbon allocation through a young Pinus taeda stand following pulse-labeling with 13CO2 and two levels of shading. The field component of this project provided process-oriented data that was used to evaluate and improve terrestrial biosphere model simulations of rapid shifts in carbon allocation and hydrological dynamics under varying environmental conditions. Here we tested the performance of the Community Land Model version 4 (CLM4) in capturing short-term carbon and water dynamics in relation to manipulative shading treatments, and the timing and magnitude of carbon fluxes through various compartments of the ecosystem. For CLM4 to closely simulate pretreatment conditions, we calibrated select model parameters with pretreatment observational data. Compared to CLM4 simulations with default parameters, CLM4 with calibrated model parameters was able to better simulate pretreatment vegetation carbon pools, light response curves, and other initial states and fluxes of carbon and water. Over a 3 week treatment period, the calibrated CLM4 generally reproduced the impacts of shading on average soil moisture at 15-95 cm depth, transpiration, relative change in stem carbon, and soil CO2 efflux rate, although some discrepancies in the estimation of magnitudes and temporal evolutions existed. CLM4, however, was not able to track the progression of the 13CO2 label from the atmosphere through foliage, phloem, roots or surface soil CO2 efflux, even when optimized model parameters were used. This model bias arises, in part, from the lack of a short-term non-structural carbohydrate storage pool and progressive timing of within-plant transport, thus indicating a need for future work to improve the allocation routines in CLM4. Overall, these types

  4. Evaluating the Community Land Model in a pine stand with shading manipulations and 13CO2 labeling

    DOE PAGES

    Mao, Jiafu; Ricciuto, Daniel M.; Thornton, Peter E.; Warren, Jeffrey M.; King, Anthony Wayne; Shi, Xiaoying; Iversen, Colleen M.; Norby, Richard J.

    2016-02-03

    Carbon partitioning and flow through ecosystems regulates land surface atmosphere CO2 exchange and thus is a key, albeit uncertain component of mechanistic models. The Partitioning in Trees and Soil (PiTS) experiment-model project tracked C partitioning through a young Pinus taeda stand following pulse-labeling with 13CO2 and two levels of shading. The field component of this project provided process-oriented data that was used to evaluate and improve terrestrial biosphere model simulations of rapid shifts in carbon partitioning and hydrological dynamics under varying environmental conditions. Here we tested the performance of the Community Land Model version 4 (CLM4) in capturing short-term carbonmore » and water dynamics in relation to manipulative shading treatments, and the timing and magnitude of carbon fluxes through various compartments of the ecosystem. To constrain CLM4 to closely simulate pretreatment conditions, we calibrated select model parameters with the pretreatment observational data. Compared to CLM4 simulations with default parameters, CLM4 with calibrated model parameters was better able to simulate pretreatment vegetation carbon pools, light response curves, and other initial states and fluxes of carbon and water. Over a 3-week treatment period, the calibrated CLM4 generally reproduced the impacts of shading on average soil moisture at 15-95 cm depth, transpiration, relative change in stem carbon, and soil CO2 efflux rate, although some discrepancies in the estimation of magnitudes and temporal evolutions existed. CLM4, however, was not able to track the progression of the 13CO2 label from the atmosphere through foliage, phloem, roots or surface soil CO2 efflux, even when optimized model parameters were used. This model bias arises, in part, from the lack of a short-term non-structural carbohydrate storage pool and progressive timing of within-plant transport, thus indicating a need for future work to improve the allocation routines in CLM4

  5. 13C Tracking after 13CO2 Supply Revealed Diurnal Patterns of Wood Formation in Aspen1

    PubMed Central

    Mahboubi, Amir; Linden, Pernilla; Moritz, Thomas

    2015-01-01

    Wood of trees is formed from carbon assimilated in the photosynthetic tissues. Determining the temporal dynamics of carbon assimilation, subsequent transport into developing wood, and incorporation to cell walls would further our understanding of wood formation in particular and tree growth in general. To investigate these questions, we designed a 13CO2 labeling system to study carbon transport and incorporation to developing wood of hybrid aspen (Populus tremula × tremuloides). Tracking of 13C incorporation to wood over a time course using nuclear magnetic resonance spectroscopy revealed diurnal patterns in wood cell wall biosynthesis. The dark period had a differential effect on 13C incorporation to lignin and cell wall carbohydrates. No 13C was incorporated into aromatic amino acids of cell wall proteins in the dark, suggesting that cell wall protein biosynthesis ceased during the night. The results show previously unrecognized temporal patterns in wood cell wall biosynthesis, suggest diurnal cycle as a possible cue in the regulation of carbon incorporation to wood, and establish a unique 13C labeling method for the analysis of wood formation and secondary growth in trees. PMID:25931520

  6. Seasonal variations of belowground carbon transfer assessed by in situ 13CO2 pulse labelling of trees

    NASA Astrophysics Data System (ADS)

    Epron, D.; Ngao, J.; Dannoura, M.; Bakker, M. R.; Zeller, B.; Bazot, S.; Bosc, A.; Plain, C.; Lata, J. C.; Priault, P.; Barthes, L.; Loustau, D.

    2011-02-01

    Soil CO2 efflux is the main source of CO2 from forest ecosystems and it is tightly coupled to the transfer of recent photosynthetic assimilates belowground and their metabolism in roots, mycorrhiza and rhizosphere microorganisms feeding on root-derived exudates. The objectives of our study were to assess patterns of belowground carbon allocation among tree species and along seasons. Pure 13CO2 pulse labelling of the entire crown of three different tree species (beech, oak and pine) was carried out at distinct phenological stages. Excess 13C in soil CO2 efflux was tracked using tunable diode laser absorption spectrometry to determine time lags between the start of the labelling and the appearance of 13C in soil CO2 efflux and the amount of 13C allocated to soil CO2 efflux. Isotope composition (δ13C) of CO2 respired by fine roots and soil microbes was measured at several occasions after labelling, together with δ13C of bulk root tissue and microbial carbon. Time lags ranged from 0.5 to 1.3 days in beech and oak and were longer in pine (1.6-2.7 days during the active growing season, more than 4 days during the resting season), and the transfer of C to the microbial biomass was as fast as to the fine roots. The amount of 13C allocated to soil CO2 efflux was estimated from a compartment model. Seasonal patterns of carbon allocation to soil CO2 efflux differed markedly between species, with pronounced seasonal variations in pine and beech. In beech, it may reflect competition with other sinks (aboveground growth in late spring and storage in late summer) that were not observed in oak.

  7. Multiscale observations of CO2, 13CO2, and pollutants at Four Corners for emission verification and attribution.

    PubMed

    Lindenmaier, Rodica; Dubey, Manvendra K; Henderson, Bradley G; Butterfield, Zachary T; Herman, Jay R; Rahn, Thom; Lee, Sang-Hyun

    2014-06-10

    There is a pressing need to verify air pollutant and greenhouse gas emissions from anthropogenic fossil energy sources to enforce current and future regulations. We demonstrate the feasibility of using simultaneous remote sensing observations of column abundances of CO2, CO, and NO2 to inform and verify emission inventories. We report, to our knowledge, the first ever simultaneous column enhancements in CO2 (3-10 ppm) and NO2 (1-3 Dobson Units), and evidence of δ(13)CO2 depletion in an urban region with two large coal-fired power plants with distinct scrubbing technologies that have resulted in ∆NOx/∆CO2 emission ratios that differ by a factor of two. Ground-based total atmospheric column trace gas abundances change synchronously and correlate well with simultaneous in situ point measurements during plume interceptions. Emission ratios of ∆NOx/∆CO2 and ∆SO2/∆CO2 derived from in situ atmospheric observations agree with those reported by in-stack monitors. Forward simulations using in-stack emissions agree with remote column CO2 and NO2 plume observations after fine scale adjustments. Both observed and simulated column ∆NO2/∆CO2 ratios indicate that a large fraction (70-75%) of the region is polluted. We demonstrate that the column emission ratios of ∆NO2/∆CO2 can resolve changes from day-to-day variation in sources with distinct emission factors (clean and dirty power plants, urban, and fires). We apportion these sources by using NO2, SO2, and CO as signatures. Our high-frequency remote sensing observations of CO2 and coemitted pollutants offer promise for the verification of power plant emission factors and abatement technologies from ground and space.

  8. Multiscale observations of CO2, 13CO2, and pollutants at Four Corners for emission verification and attribution.

    PubMed

    Lindenmaier, Rodica; Dubey, Manvendra K; Henderson, Bradley G; Butterfield, Zachary T; Herman, Jay R; Rahn, Thom; Lee, Sang-Hyun

    2014-06-10

    There is a pressing need to verify air pollutant and greenhouse gas emissions from anthropogenic fossil energy sources to enforce current and future regulations. We demonstrate the feasibility of using simultaneous remote sensing observations of column abundances of CO2, CO, and NO2 to inform and verify emission inventories. We report, to our knowledge, the first ever simultaneous column enhancements in CO2 (3-10 ppm) and NO2 (1-3 Dobson Units), and evidence of δ(13)CO2 depletion in an urban region with two large coal-fired power plants with distinct scrubbing technologies that have resulted in ∆NOx/∆CO2 emission ratios that differ by a factor of two. Ground-based total atmospheric column trace gas abundances change synchronously and correlate well with simultaneous in situ point measurements during plume interceptions. Emission ratios of ∆NOx/∆CO2 and ∆SO2/∆CO2 derived from in situ atmospheric observations agree with those reported by in-stack monitors. Forward simulations using in-stack emissions agree with remote column CO2 and NO2 plume observations after fine scale adjustments. Both observed and simulated column ∆NO2/∆CO2 ratios indicate that a large fraction (70-75%) of the region is polluted. We demonstrate that the column emission ratios of ∆NO2/∆CO2 can resolve changes from day-to-day variation in sources with distinct emission factors (clean and dirty power plants, urban, and fires). We apportion these sources by using NO2, SO2, and CO as signatures. Our high-frequency remote sensing observations of CO2 and coemitted pollutants offer promise for the verification of power plant emission factors and abatement technologies from ground and space. PMID:24843169

  9. Evaluating the Community Land Model in a pine stand with shading manipulations and 13CO2 labeling

    NASA Astrophysics Data System (ADS)

    Mao, J.; Ricciuto, D. M.; Thornton, P. E.; Warren, J. M.; King, A. W.; Shi, X.; Iversen, C. M.; Norby, R. J.

    2016-02-01

    Carbon allocation and flow through ecosystems regulates land surface-atmosphere CO2 exchange and thus is a key, albeit uncertain, component of mechanistic models. The Partitioning in Trees and Soil (PiTS) experiment-model project tracked carbon allocation through a young Pinus taeda stand following pulse labeling with 13CO2 and two levels of shading. The field component of this project provided process-oriented data that were used to evaluate terrestrial biosphere model simulations of rapid shifts in carbon allocation and hydrological dynamics under varying environmental conditions. Here we tested the performance of the Community Land Model version 4 (CLM4) in capturing short-term carbon and water dynamics in relation to manipulative shading treatments and the timing and magnitude of carbon fluxes through various compartments of the ecosystem. When calibrated with pretreatment observations, CLM4 was capable of closely simulating stand-level biomass, transpiration, leaf-level photosynthesis, and pre-labeling 13C values. Over the 3-week treatment period, CLM4 generally reproduced the impacts of shading on soil moisture changes, relative change in stem carbon, and soil CO2 efflux rate. Transpiration under moderate shading was also simulated well by the model, but even with optimization we were not able to simulate the high levels of transpiration observed in the heavy shading treatment, suggesting that the Ball-Berry conductance model is inadequate for these conditions. The calibrated version of CLM4 gave reasonable estimates of label concentration in phloem and in soil surface CO2 after 3 weeks of shade treatment, but it lacks the mechanisms needed to track the labeling pulse through plant tissues on shorter timescales. We developed a conceptual model for photosynthate transport based on the experimental observations, and we discussed conditions under which the hypothesized mechanisms could have an important influence on model behavior in larger-scale applications

  10. Exercise and the oxidation and storage of glucose, maize-syrup solids and sucrose determined from breath 13CO2.

    PubMed

    Leese, G P; Thompson, J; Scrimgeour, C M; Rennie, M J

    1996-01-01

    In order to determine which of maize syrup solids, glucose and sucrose were more readily oxidised during exercise and least readily oxidised afterwards, the rates of oxidation of three almost identical isoenergetic solutions of carbohydrates (330 ml of 18.5% w/v solutions of glucose, maize syrup solids and sucrose, 989-1050 kJ total energy) naturally enriched with 13C were examined at rest and during and after 1 h uphill walking at 75% maximum oxygen uptake (VO2max) in nine subjects [mean (SEM) VO2max, 45.4 (0.9) ml.kg-1.min-1]. Rates of production of expired 13CO2 were used to estimate rates of oxidation of each exogenous substrate. Energy expenditure and the contributions from total carbohydrate and fat oxidation were calculated from whole-body gas exchange. At rest, maize syrup solids were oxidised less than sucrose during the 1st h [glucose 2.7 (0.2) g.h-1, maize syrup solids 1.9 (0.3) g.h-1, sucrose 3.7 (0.2) g.h-1; maize syrup solids vs sucrose P < 0.01], but this difference disappeared after a further 3 h at rest [glucose 8.3 (0.5) g.h-1, maize syrup solids 7.7 (0.5) g.h-1, sucrose 8.1 (0.4) g.h-1]. During exercise, all the carbohydrates were oxidised to the same extent [glucose 23.0 (2.8) g.h-1, maize syrup solids 23.9 (3.4) g.h-1, sucrose 27.5 (2.6) g.h-1) but during 4 h of recovery after exercise, maize syrup solids were oxidised least [glucose 4.6 (0.1) g.h-1, maize syrup solids 3.7 (0.1) g.h-1, sucrose 6.4 (0.1) g.h-1; P < 0.05] suggesting that it may be stored to a greater extent. The results suggest that 18.5% glucose, maize syrup solids and sucrose solutions were equally well oxidised during exercise. During recovery from exercise maize syrup solids were oxidised less than glucose, which in turn was oxidised less than sucrose.

  11. Partitioning net ecosystem carbon exchange into net assimilation and respiration using 13CO2 measurements: A cost-effective sampling strategy

    NASA Astrophysics Data System (ADS)

    OgéE, J.; Peylin, P.; Ciais, P.; Bariac, T.; Brunet, Y.; Berbigier, P.; Roche, C.; Richard, P.; Bardoux, G.; Bonnefond, J.-M.

    2003-06-01

    The current emphasis on global climate studies has led the scientific community to set up a number of sites for measuring the long-term biosphere-atmosphere net CO2 exchange (net ecosystem exchange, NEE). Partitioning this flux into its elementary components, net assimilation (FA), and respiration (FR), remains necessary in order to get a better understanding of biosphere functioning and design better surface exchange models. Noting that FR and FA have different isotopic signatures, we evaluate the potential of isotopic 13CO2 measurements in the air (combined with CO2 flux and concentration measurements) to partition NEE into FR and FA on a routine basis. The study is conducted at a temperate coniferous forest where intensive isotopic measurements in air, soil, and biomass were performed in summer 1997. The multilayer soil-vegetation-atmosphere transfer model MuSICA is adapted to compute 13CO2 flux and concentration profiles. Using MuSICA as a "perfect" simulator and taking advantage of the very dense spatiotemporal resolution of the isotopic data set (341 flasks over a 24-hour period) enable us to test each hypothesis and estimate the performance of the method. The partitioning works better in midafternoon when isotopic disequilibrium is strong. With only 15 flasks, i.e., two 13CO2 nighttime profiles (to estimate the isotopic signature of FR) and five daytime measurements (to perform the partitioning) we get mean daily estimates of FR and FA that agree with the model within 15-20%. However, knowledge of the mesophyll conductance seems crucial and may be a limitation to the method.

  12. Biogenic volatile organic compounds (BVOCs) emission of Scots pine under drought stress - a 13CO2 labeling study to determine de novo and pool emissions under different treatments

    NASA Astrophysics Data System (ADS)

    Lüpke, M.

    2015-12-01

    Plants emit biogenic volatile organic compounds (BVOCs) to e.g. communicate and to defend herbivores. Yet BVOCs also impact atmospheric chemistry processes, and lead to e.g. the built up of secondary organic aerosols. Abiotic stresses, such as drought, however highly influence plant physiology and subsequently BVOCs emission rates. In this study, we investigated the effect of drought stress on BVOCs emission rates of Scots pine trees, a de novo and pool emitter, under controlled climate chamber conditions within a dynamic enclosure system consisting of four plant chambers. Isotopic labeling with 13CO2 was used to detect which ratio of emissions of BVOCs derives from actual synthesis and from storage organs under different treatments. Additionally, the synthesis rate of the BVOCs synthesis can be determined. The experiment consisted of two campaigns (July 2015 and August 2015) of two control and two treated trees respectively in four controlled dynamic chambers simultaneously. Each campaign lasted for around 21 days and can be split into five phases: adaptation, control, dry-out, drought- and re-watering phase. The actual drought phase lasted around five days. During the campaigns two samples of BVOCs emissions were sampled per day and night on thermal desorption tubes and analyzed by a gas chromatograph coupled with a mass spectrometer and a flame ionization detector. Additionally, gas exchange of water and CO2, soil moisture, as well as leaf and chamber temperature was monitored continuously. 13CO2 labeling was performed simultaneously in all chambers during the phases control, drought and re-watering for five hours respectively. During the 13CO2 labeling four BVOCs emission samples per chamber were taken to identify the labeling rate on emitted BVOCs. First results show a decrease of BVOCs emissions during the drought phase and a recovery of emission after re-watering, as well as different strength of reduction of single compounds. The degree of labeling with 13

  13. Clinically-relevant reperfusion in acute ischemic stroke MTT performs better than Tmax and TTP

    PubMed Central

    Kong, Linglong; Zhu, Hongtu; Vo, Katie D.; Powers, William J.; Lin, Weili; Lee, Jin-Moo

    2014-01-01

    Background While several MRI parameters are used to assess tissue perfusion during hyperacute stroke, it is unclear which is optimal for measuring clinically-relevant reperfusion. We directly compared MTT prolongation (MTTp), TTP, and time-to-maximum (Tmax) to determine which best predicted neurological improvement and tissue salvage following early reperfusion. Methods Acute ischemic stroke patients underwent three MRI's: <4.5hr (tp1), at 6hr (tp2), and at 1 month after onset. Perfusion deficits at tp1 and tp2 were defined by MTTp, TTP, or Tmax beyond four commonly-used thresholds. Percent reperfusion (%Reperf) was calculated for each parameter and threshold. Regression analysis was used to fit %Reperf for each parameter and threshold as a predictor of neurological improvement [defined as admission National Institutes of Health Stroke Scale (NIHSS) – 1 month NIHSS (ΔNIHSS)] after adjusting for baseline clinical variables. Volume of reperfusion, for each parameter and threshold, was correlated with tissue salvage, defined as tp1 perfusion deficit volume – final infarct volume. Results 50 patients were scanned at 2.7 hours and 6.2 hours after stroke onset. %Reperf predicted ΔNIHSS for all MTTp thresholds, for Tmax > 6s and > 8s, but for no TTP thresholds. Tissue salvage significantly correlated with reperfusion for all MTTp thresholds and with Tmax > 6s, while there was no correlation with any TTP threshold. Among all parameters, reperfusion defined by MTTp was most strongly associated with ΔNIHSS (MTTp>3s, p=0.0002) and tissue salvage (MTTp> 3s and 4s, P<0.0001). Conclusion MTT-defined reperfusion was the best predictor of neurological improvement and tissue salvage in hyperacute ischemic stroke. PMID:24500786

  14. Effects of waterlogging on carbon assimilate partitioning in the Zoigê alpine wetlands revealed by 13CO2 pulse labeling.

    PubMed

    Gao, Jun-Qin; Gao, Ju-Juan; Zhang, Xue-Wen; Xu, Xing-Liang; Deng, Zhao-Heng; Yu, Fei-Hai

    2015-01-01

    Waterlogging has been suggested to affect carbon (C) turnover in wetlands, but how it affects C allocation and stocks remains unclear in alpine wetlands. Using in situ (13)CO2 pulse labelling, we investigated C allocation in both waterlogged and non-waterlogged sites in the Zoigê wetlands on the Tibetan Plateau in August 2011. More than 50% of total (13)C fixed by photosynthesis was lost via shoot respiration. Shoots recovered about 19% of total (13)C fixed by photosynthesis at both sites. Only about 26% of total fixed (13)C was translocated into the belowground pools. Soil organic C pool accounted for 19% and roots recovered about 5-7% of total fixed (13)C at both sites. Waterlogging significantly reduced soil respiration and very little (13)C was lost via soil respiration in the alpine wetlands compared to that in grasslands. We conclude that waterlogging did not significantly alter C allocations among the C pools except the (13)CO2 efflux derived from soil respiration and that shoots made similar contributions to C sequestration as the belowground parts in the Zoigê alpine wetlands. Therefore, changes in waterlogging due to climate change will not affect C assimilate partitioning but soil C efflux. PMID:25797457

  15. Effects of waterlogging on carbon assimilate partitioning in the Zoigê alpine wetlands revealed by 13CO2 pulse labeling.

    PubMed

    Gao, Jun-Qin; Gao, Ju-Juan; Zhang, Xue-Wen; Xu, Xing-Liang; Deng, Zhao-Heng; Yu, Fei-Hai

    2015-03-23

    Waterlogging has been suggested to affect carbon (C) turnover in wetlands, but how it affects C allocation and stocks remains unclear in alpine wetlands. Using in situ (13)CO2 pulse labelling, we investigated C allocation in both waterlogged and non-waterlogged sites in the Zoigê wetlands on the Tibetan Plateau in August 2011. More than 50% of total (13)C fixed by photosynthesis was lost via shoot respiration. Shoots recovered about 19% of total (13)C fixed by photosynthesis at both sites. Only about 26% of total fixed (13)C was translocated into the belowground pools. Soil organic C pool accounted for 19% and roots recovered about 5-7% of total fixed (13)C at both sites. Waterlogging significantly reduced soil respiration and very little (13)C was lost via soil respiration in the alpine wetlands compared to that in grasslands. We conclude that waterlogging did not significantly alter C allocations among the C pools except the (13)CO2 efflux derived from soil respiration and that shoots made similar contributions to C sequestration as the belowground parts in the Zoigê alpine wetlands. Therefore, changes in waterlogging due to climate change will not affect C assimilate partitioning but soil C efflux.

  16. 13CO2/12CO2 ratio analysis in exhaled air by lead-salt tunable diode lasers for noninvasive diagnostics in gastroenterology

    NASA Astrophysics Data System (ADS)

    Stepanov, Eugene V.; Zyrianov, Pavel V.; Miliaev, Valerii A.; Selivanov, Yurii G.; Chizhevskii, Eugene G.; Os'kina, Svetlana; Ivashkin, Vladimir T.; Nikitina, Elena I.

    1999-07-01

    An analyzer of 13CO2/12CO2 ratio in exhaled air based on lead-salt tunable diode lasers is presented. High accuracy of the carbon isotope ratio detection in exhaled carbon dioxide was achieved with help of very simple optical schematics. It was based on the use of MBE laser diodes operating in pulse mode and on recording the resonance CO2 absorption at 4.2 micrometers . Special fast acquisition electronics and software were applied for spectral data collection and processing. Developed laser system was tested in a clinical train aimed to assessment eradication efficiency in therapy of gastritis associated with Helicobacter pylori infection. Data on the 13C-urea breath test used for P.pylori detection and obtained with tunable diode lasers in the course of the trail was compared with the results of Mass-Spectroscopy analysis and histology observations. The analyzer can be used also for 13CO2/12CO2 ratio detection in exhalation to perform gastroenterology breath test based on using other compounds labeled with stable isotopes.

  17. Riverine GHG emissions: one year of CO2, 13CO2 and CH4 flux measurements on Vistula river in Krakow, southern Poland

    NASA Astrophysics Data System (ADS)

    Jasek, Alina; Wachniew, Przemyslaw; Zimnoch, Miroslaw

    2013-04-01

    Terrestrial surface waters are generally considered to be sources of carbon dioxide and methane, because respiration of organic matter via aerobic and anaerobic pathways causes supersaturation of surface waters with respect to CO2 and CH4, respectively. In rivers, these processes are influenced by such anthropogenic factors as changes of land-use, wastewater and alteration of river channels. The research object is Vistula, the largest Polish river. It has the length of 1047 km and annual runoff of 6.2x1010m3. The urban section of Vistula in Krakow receives large amounts of organic matter from highly urbanized catchment and point discharges of urban waste waters within the city limits. The river was sampled regularly at three points: the entrance to the city, the center and the point where Vistula leaves the agglomeration. A floating chamber coupled with Picarro G2101-i analyzer was applied to quantify CO2, 13CO2 and CH4 fluxes leaving the surface of the river. A floating chamber was equipped with sensors to measure air pressure, temperature and humidity inside the chamber and the temperature of water. The chamber was equipped with a set of floats and an anchor. The measurements started in October 2011, and were repeated with approximately monthly frequency. Physicochemical properties of water (temperature, conductivity, pH, CO2 partial pressure over the water surface and alkalinity) were also measured during each measurement campaign. In addition, at each site short-term variability of the measured fluxes was also investigated. Additionally, short-term variability of the measured fluxes of CO2, 13CO2 and CH4 were performed in all three sites. The results indicate that fluxes of CO2 released from the river are comparable with the soil emissions of this gas measured in Krakow area. The δ13CO2 signature of riverine CO2 flux allowed to identify decomposition of C3 organic matter as the major source of this gas. No distinct seasonal variability of the CO2 emission and

  18. Determination of de novo and pool emissions of terpenes from four common boreal/alpine trees by 13CO2 labelling and PTR-MS analysis.

    PubMed

    Ghirardo, Andrea; Koch, Kristine; Taipale, Risto; Zimmer, Ina; Schnitzler, Jörg-Peter; Rinne, Janne

    2010-05-01

    Boreal forests emit a large amount of monoterpenes into the atmosphere. Traditionally these emissions are assumed to originate as evaporation from large storage pools. Thus, their diurnal cycle would depend mostly on temperature. However, there is indication that a significant part of the monoterpene emission would originate directly from de novo synthesis. By applying 13CO2 fumigation and analyzing the isotope fractions with proton transfer reaction mass spectrometry (PTR-MS) and classical GC-MS, we determined the fractions of monoterpene emissions originating from de novo biosynthesis in Pinus sylvestris (58%), Picea abies (33.5%), Larix decidua (9.8%) and Betula pendula (100%). Application of the observed split between de novo and pool emissions from P. sylvestris in a hybrid emission algorithm resulted in a better description of ecosystem scale monoterpene emissions from a boreal Scots pine forest stand.

  19. 13CO2 pulse labelling of plants in tandem with stable isotope probing: methodological considerations for examining microbial function in the rhizosphere.

    PubMed

    Griffiths, Robert I; Manefield, Mike; Ostle, Nick; McNamara, Niall; O'Donnell, Anthony G; Bailey, Mark J; Whiteley, Andrew S

    2004-07-01

    Recently developed 13CO2 pulse labelling and stable isotope probing (SIP) methods offer the potential to track 13C-labelled plant photosynthate into phylogenetic groups of microbial taxa in the rhizosphere, permitting an examination of the link between soil microbial diversity and carbon flow in situ. We tested the feasibility of this approach to detect functional differences in microbial communities utilising recently fixed plant photosynthate in moisture perturbed grassland turfs. Specifically, we addressed two questions: (1) How does moisture perturbation (three treatments; continual wetting, drying, and drying followed by rewetting) affect the assimilation of 13C-labelled exudates carbon into the soil microbial community?; (2) Can 13C deposited in soil from pulse-labelled plants be used to identify microbes utilising plant exudates using SIP methodologies? Net CO2 fluxes showed that prior to 13CO2 pulse labelling, all treatments were photosynthetically active, but differences were observed in night time respiration, indicating moisture treatments had impacted on net CO2 efflux. Measurements of pulse-derived 13C incorporated into soil RNA over 2 months showed that there was only evidence of 13C enrichment in the continuously wetted treatments. However, isotopic values represented only a 0.1-0.2 13C at.% increase over natural abundance levels and were found to be insufficient for the application of RNA-SIP. These findings reveal that in this experimental system, the microbial uptake of labelled carbon from plant exudates is low, and further optimisation of methodologies may be required for application of SIP to natural plant-soil systems where 13C tracer dilution is a consideration. PMID:15177910

  20. IRAM 30 m large scale survey of {sup 12}CO(2-1) and {sup 13}CO(2-1) emission in the Orion molecular cloud

    SciTech Connect

    Berné, O.; Cernicharo, J.; Marcelino, N.

    2014-11-01

    Using the IRAM 30 m telescope, we have surveyed a 1 × 0.°8 part of the Orion molecular cloud in the {sup 12}CO and {sup 13}CO (2-1) lines with a maximal spatial resolution of ∼11'' and spectral resolution of ∼0.4 km s{sup –1}. The cloud appears filamentary, clumpy, and with a complex kinematical structure. We derive an estimated mass of the cloud of 7700 M {sub ☉} (half of which is found in regions with visual extinctions A{sub V} below ∼10) and a dynamical age for the nebula of the order of 0.2 Myr. The energy balance suggests that magnetic fields play an important role in supporting the cloud, at large and small scales. According to our analysis, the turbulent kinetic energy in the molecular gas due to outflows is comparable to turbulent kinetic energy resulting from the interaction of the cloud with the H II region. This latter feedback appears negative, i.e., the triggering of star formation by the H II region is inefficient in Orion. The reduced data as well as additional products such as the column density map are made available online (http://userpages.irap.omp.eu/∼oberne/Olivier{sub B}erne/Data).

  1. 13CO2/12CO2 isotope ratio analysis in human breath using a 2 μm diode laser

    NASA Astrophysics Data System (ADS)

    Sun, Mingguo; Cao, Zhensong; Liu, Kun; Wang, Guishi; Tan, Tu; Gao, Xiaoming; Chen, Weidong; Yinbo, Huang; Ruizhong, Rao

    2015-04-01

    The bacterium H. pylori is believed to cause peptic ulcer. H. pylori infection in the human stomach can be diagnosed through a CO2 isotope ratio measure in exhaled breath. A laser spectrometer based on a distributed-feedback semiconductor diode laser at 2 μm is developed to measure the changes of 13CO2/12CO2 isotope ratio in exhaled breath sample with the CO2 concentration of ~4%. It is characterized by a simplified optical layout, in which a single detector and associated electronics are used to probe CO2 spectrum. A new type multi-passes cell with 12 cm long base length , 29 m optical path length in total and 280 cm3 volume is used in this work. The temperature and pressure are well controlled at 301.15 K and 6.66 kPa with fluctuation amplitude of 25 mK and 6.7 Pa, respectively. The best 13δ precision of 0.06o was achieved by using wavelet denoising and Kalman filter. The application of denoising and Kalman filter not only improved the signal to noise ratio, but also shorten the system response time.

  2. Carbon Allocation of 13CO2-labeled Photoassimilate in Larix gmelinii Saplings - A Physiological Basis for Isotope Dendroclimatology in Eastern Siberia.

    NASA Astrophysics Data System (ADS)

    Kagawa, A.; Sugimoto, A.; Maximov, T. C.

    2006-12-01

    Tree-ring density and widths have been successfully used to reconstruct summer temperatures in high- northern latitudes, although a discrepancy between tree-growth and temperature has been found for recent decades. The so-called "reduced sensitivity" of tree rings to summer temperatures has been observed especially strongly in northern Siberia (Briffa et al., 1998) and drought stress (increased water use efficiency) arose from global warming and/or increasing CO2 are suggested as causes (Barber et al. 2000, Saurer et al. 2004). By using carbon isotope ratio as an indicator of drought stress and ring-width/density as indicators of growth, we can clarify how drought stress caused by recent global warming affects wood formation of Siberian trees. However, isotope dendroclimatology is still in its infancy and our understanding of basic physiological processes of isotope signal transfer from leaves to tree rings is insufficient. In order to understand translocation, storage, and allocation of photoassimilate to different organs of trees, we pulse- labeled ten L. gmelinii growing in a continuous permafrost zone with stable 13CO2. We studied seasonal course of carbon allocation patterns of photoassimilate among needles, branches, stem and roots and also how spring, summer, and autumn photoassimilate is later used for both earlywood and latewood formation. About half of the carbon in new needles was derived from stored material. The starch pool in non- needle parts, which can be used for xylem formation, drew about 43 percent of its carbon from previous year's photoassimilate, suggesting that carbon storage is the key mechanism behind autocorrelation in (isotope) dendroclimatology. Analysis of intra-annual 13C of the tree rings formed after the labeling revealed that earlywood contained photoassimilate from the previous summer and autumn as well as from the current spring. Latewood was mainly composed of photoassimilate from the current year's summer/autumn, although it

  3. Rapid, Long-term Monitoring of CO2 Concentration and δ13CO2 at CCUS Sites Allows Discrimination of Leakage Patterns from Natural Background Values

    NASA Astrophysics Data System (ADS)

    Galfond, B.; Riemer, D. D.; Swart, P. K.

    2014-12-01

    In order for Carbon Capture Utilization and Storage (CCUS) to gain wide acceptance as a method for mitigating atmospheric CO2 concentrations, schemes must be devised to ensure that potential leakage is detected. New regulations from the US Environmental Protection Agency require monitoring and accounting for Class VI injection wells, which will remain a barrier to wide scale CCUS deployment until effective and efficient monitoring techniques have been developed and proven. Monitoring near-surface CO2 at injection sites to ensure safety and operational success requires high temporal resolution CO2 concentration and carbon isotopic (δ13C) measurements. The only technologies currently capable of this rapid measurement of δ13C are optical techniques such as Cavity Ringdown Spectroscopy (CRDS). We have developed a comprehensive remote monitoring approach using CRDS and a custom manifold system to obtain accurate rapid measurements from a large sample area over an extended study period. Our modified Picarro G1101-i CRDS allows for automated rapid and continuous field measurement of δ13CO2 and concentrations of relevant gas species. At our field site, where preparations have been underway for Enhanced Oil Recovery (EOR) operations, we have been able to measure biogenic effects on a diurnal scale, as well as variation due to precipitation and seasonality. Taking these background trends into account, our statistical treatment of real data has been used to improve signal-to-noise ratios by an order of magnitude over published models. Our system has proven field readiness for the monitoring of sites with even modest CO2 fluxes.

  4. Quantifying protein synthesis and degradation in Arabidopsis by dynamic 13CO2 labeling and analysis of enrichment in individual amino acids in their free pools and in protein.

    PubMed

    Ishihara, Hirofumi; Obata, Toshihiro; Sulpice, Ronan; Fernie, Alisdair R; Stitt, Mark

    2015-05-01

    Protein synthesis and degradation represent substantial costs during plant growth. To obtain a quantitative measure of the rate of protein synthesis and degradation, we supplied (13)CO2 to intact Arabidopsis (Arabidopsis thaliana) Columbia-0 plants and analyzed enrichment in free amino acids and in amino acid residues in protein during a 24-h pulse and 4-d chase. While many free amino acids labeled slowly and incompletely, alanine showed a rapid rise in enrichment in the pulse and a decrease in the chase. Enrichment in free alanine was used to correct enrichment in alanine residues in protein and calculate the rate of protein synthesis. The latter was compared with the relative growth rate to estimate the rate of protein degradation. The relative growth rate was estimated from sequential determination of fresh weight, sequential images of rosette area, and labeling of glucose in the cell wall. In an 8-h photoperiod, protein synthesis and cell wall synthesis were 3-fold faster in the day than at night, protein degradation was slow (3%-4% d(-1)), and flux to growth and degradation resulted in a protein half-life of 3.5 d. In the starchless phosphoglucomutase mutant at night, protein synthesis was further decreased and protein degradation increased, while cell wall synthesis was totally inhibited, quantitatively accounting for the inhibition of growth in this mutant. We also investigated the rates of protein synthesis and degradation during leaf development, during growth at high temperature, and compared synthesis rates of Rubisco large and small subunits of in the light and dark. PMID:25810096

  5. Quantifying protein synthesis and degradation in Arabidopsis by dynamic 13CO2 labeling and analysis of enrichment in individual amino acids in their free pools and in protein.

    PubMed

    Ishihara, Hirofumi; Obata, Toshihiro; Sulpice, Ronan; Fernie, Alisdair R; Stitt, Mark

    2015-05-01

    Protein synthesis and degradation represent substantial costs during plant growth. To obtain a quantitative measure of the rate of protein synthesis and degradation, we supplied (13)CO2 to intact Arabidopsis (Arabidopsis thaliana) Columbia-0 plants and analyzed enrichment in free amino acids and in amino acid residues in protein during a 24-h pulse and 4-d chase. While many free amino acids labeled slowly and incompletely, alanine showed a rapid rise in enrichment in the pulse and a decrease in the chase. Enrichment in free alanine was used to correct enrichment in alanine residues in protein and calculate the rate of protein synthesis. The latter was compared with the relative growth rate to estimate the rate of protein degradation. The relative growth rate was estimated from sequential determination of fresh weight, sequential images of rosette area, and labeling of glucose in the cell wall. In an 8-h photoperiod, protein synthesis and cell wall synthesis were 3-fold faster in the day than at night, protein degradation was slow (3%-4% d(-1)), and flux to growth and degradation resulted in a protein half-life of 3.5 d. In the starchless phosphoglucomutase mutant at night, protein synthesis was further decreased and protein degradation increased, while cell wall synthesis was totally inhibited, quantitatively accounting for the inhibition of growth in this mutant. We also investigated the rates of protein synthesis and degradation during leaf development, during growth at high temperature, and compared synthesis rates of Rubisco large and small subunits of in the light and dark.

  6. In situ 13CO2 pulse labelling of field-grown eucalypt trees revealed the effects of potassium nutrition and throughfall exclusion on phloem transport of photosynthetic carbon.

    PubMed

    Epron, Daniel; Cabral, Osvaldo Machado Rodrigues; Laclau, Jean-Paul; Dannoura, Masako; Packer, Ana Paula; Plain, Caroline; Battie-Laclau, Patricia; Moreira, Marcelo Zacharias; Trivelin, Paulo Cesar Ocheuze; Bouillet, Jean-Pierre; Gérant, Dominique; Nouvellon, Yann

    2016-01-01

    Potassium (K) is an important limiting factor of tree growth, but little is known of the effects of K supply on the long-distance transport of photosynthetic carbon (C) in the phloem and of the interaction between K fertilization and drought. We pulse-labelled 2-year-old Eucalyptus grandis L. trees grown in a field trial combining K fertilization (+K and -K) and throughfall exclusion (+W and -W), and we estimated the velocity of C transfer by comparing time lags between the uptake of (13)CO2 and its recovery in trunk CO2 efflux recorded at different heights. We also analysed the dynamics of the labelled photosynthates recovered in the foliage and in the phloem sap (inner bark extract). The mean residence time of labelled C in the foliage was short (21-31 h). The time series of (13)C in excess in the foliage was affected by the level of fertilization, whereas the effect of throughfall exclusion was not significant. The velocity of C transfer in the trunk (0.20-0.82 m h(-1)) was twice as high in +K trees than in -K trees, with no significant effect of throughfall exclusion except for one +K -W tree labelled in the middle of the drought season that was exposed to a more pronounced water stress (midday leaf water potential of -2.2 MPa). Our results suggest that besides reductions in photosynthetic C supply and in C demand by sink organs, the lower velocity under K deficiency is due to a lower cross-sectional area of the sieve tubes, whereas an increase in phloem sap viscosity is more likely limiting phloem transport under drought. In all treatments, 10 times less (13)C was recovered in inner bark extracts at the bottom of the trunk when compared with the base of the crown, suggesting that a large part of the labelled assimilates has been exported out of the phloem and replaced by unlabelled C. This supports the 'leakage-retrieval mechanism' that may play a role in maintaining the pressure gradient between source and sink organs required to sustain high

  7. The effect of physical back-diffusion of 13CO2 tracer on the coupling between photosynthesis and soil CO2 efflux in grassland.

    PubMed

    Burri, Susanne; Sturm, Patrick; Baur, Thomas; Barthel, Matti; Knohl, Alexander; Buchmann, Nina

    2014-01-01

    Pulse labelling experiments provide a common tool to study short-term processes in the plant-soil system and investigate below-ground carbon allocation as well as the coupling of soil CO(2) efflux to photosynthesis. During the first hours after pulse labelling, the measured isotopic signal of soil CO(2) efflux is a combination of both physical tracer diffusion into and out of the soil as well as biological tracer release via root and microbial respiration. Neglecting physical back-diffusion can lead to misinterpretation regarding time lags between photosynthesis and soil CO(2) efflux in grassland or any ecosystem type where the above-ground plant parts cannot be labelled in gas-tight chambers separated from the soil. We studied the effects of physical (13)CO(2) tracer back-diffusion in pulse labelling experiments in grassland, focusing on the isotopic signature of soil CO(2) efflux. Having accounted for back-diffusion, the estimated time lag for first tracer appearance in soil CO(2) efflux changed from 0 to 1.81±0.56 h (mean±SD) and the time lag for maximum tracer appearance from 2.67±0.39 to 9.63±3.32 h (mean±SD). Thus, time lags were considerably longer when physical tracer diffusion was considered. Using these time lags after accounting for physical back-diffusion, high nocturnal soil CO(2) efflux rates could be related to daytime rates of gross primary productivity (R(2)=0.84). Moreover, pronounced diurnal patterns in the δ(13)C of soil CO(2) efflux were found during the decline of the tracer over 3 weeks. Possible mechanisms include diurnal changes in the relative contributions of autotrophic and heterotrophic soil respiration as well as their respective δ(13)C values. Thus, after accounting for physical back-diffusion, we were able to quantify biological time lags in the coupling of photosynthesis and soil CO(2) efflux in grassland at the diurnal time scale.

  8. In situ 13CO2 pulse labelling of field-grown eucalypt trees revealed the effects of potassium nutrition and throughfall exclusion on phloem transport of photosynthetic carbon.

    PubMed

    Epron, Daniel; Cabral, Osvaldo Machado Rodrigues; Laclau, Jean-Paul; Dannoura, Masako; Packer, Ana Paula; Plain, Caroline; Battie-Laclau, Patricia; Moreira, Marcelo Zacharias; Trivelin, Paulo Cesar Ocheuze; Bouillet, Jean-Pierre; Gérant, Dominique; Nouvellon, Yann

    2016-01-01

    Potassium (K) is an important limiting factor of tree growth, but little is known of the effects of K supply on the long-distance transport of photosynthetic carbon (C) in the phloem and of the interaction between K fertilization and drought. We pulse-labelled 2-year-old Eucalyptus grandis L. trees grown in a field trial combining K fertilization (+K and -K) and throughfall exclusion (+W and -W), and we estimated the velocity of C transfer by comparing time lags between the uptake of (13)CO2 and its recovery in trunk CO2 efflux recorded at different heights. We also analysed the dynamics of the labelled photosynthates recovered in the foliage and in the phloem sap (inner bark extract). The mean residence time of labelled C in the foliage was short (21-31 h). The time series of (13)C in excess in the foliage was affected by the level of fertilization, whereas the effect of throughfall exclusion was not significant. The velocity of C transfer in the trunk (0.20-0.82 m h(-1)) was twice as high in +K trees than in -K trees, with no significant effect of throughfall exclusion except for one +K -W tree labelled in the middle of the drought season that was exposed to a more pronounced water stress (midday leaf water potential of -2.2 MPa). Our results suggest that besides reductions in photosynthetic C supply and in C demand by sink organs, the lower velocity under K deficiency is due to a lower cross-sectional area of the sieve tubes, whereas an increase in phloem sap viscosity is more likely limiting phloem transport under drought. In all treatments, 10 times less (13)C was recovered in inner bark extracts at the bottom of the trunk when compared with the base of the crown, suggesting that a large part of the labelled assimilates has been exported out of the phloem and replaced by unlabelled C. This supports the 'leakage-retrieval mechanism' that may play a role in maintaining the pressure gradient between source and sink organs required to sustain high

  9. Investigating the impact of light and water status on the exchange of COS, 13CO2, CO18O and H218O from bryophytes

    NASA Astrophysics Data System (ADS)

    Gimeno, Teresa; Royles, Jessica; Ogee, Jerome; Jones, Samuel; Burlett, Regis; West, Jason; Sauze, Joana; Wohl, Steven; Genty, Bernard; Griffiths, Howard; Wingate, Lisa

    2016-04-01

    Terrestrial surfaces are often covered by photoautotrophic communities that play a significant role in the biological fixation of C and N at the global scale. Bryophytes (mosses, liverworts and hornworts) are key members in these communities and are especially adapted to thrive in hostile environments, by growing slowly and surviving repeated dehydration events. Consequently, bryophyte communities can be extremely long-lived (>1500yrs) and can serve as valuable records of historic climate change. In particular the carbon and oxygen isotope compositions of mosses can be used as powerful proxies describing how growing season changes in atmospheric CO2 and rainfall have changed in the distant past over the land surface. Interpreting the climate signals of bryophyte biomass requires a robust understanding of how changes in photosynthetic activity and moisture status regulate the growth and isotopic composition of bryophyte biomass. Thus theoretical models predicting how changes in isotopic enrichment and CO2 discrimination respond to dehydration and rehydration are used to tease apart climatic and isotopic source signals. Testing these models with high resolution datasets obtained from new generation laser spectrometers can provide more information on how these plants that lack stomata cope with water loss. In addition novel tracers such as carbonyl sulfide (COS) can also be measured at high resolution and precision (<5ppt) and used to constrain understanding of diffusional and enzymatic limitations during dehydration and rehydration events in the light and the dark. Here, we will present for the first time simultaneous high-resolution chamber measurements of COS, 13CO2, CO18O and H218O fluxes by a bryophyte species (Marchantia sp.) in the light and during the dark, through complete desiccation cycles. Our measurements consistently reveal a strong enrichment dynamic in the oxygen isotope composition of transpired water over the dessication cycle that caused an increase

  10. Using eddy covariance of CO2, 13CO2 and CH4, continuous soil respiration measurements, and PhenoCams to constrain a process-based biogeochemical model for carbon market-funded wetland restoration

    NASA Astrophysics Data System (ADS)

    Oikawa, P. Y.; Baldocchi, D. D.; Knox, S. H.; Sturtevant, C. S.; Verfaillie, J. G.; Dronova, I.; Jenerette, D.; Poindexter, C.; Huang, Y. W.

    2015-12-01

    We use multiple data streams in a model-data fusion approach to reduce uncertainty in predicting CO2 and CH4 exchange in drained and flooded peatlands. Drained peatlands in the Sacramento-San Joaquin River Delta, California are a strong source of CO2 to the atmosphere and flooded peatlands or wetlands are a strong CO2 sink. However, wetlands are also large sources of CH4 that can offset the greenhouse gas mitigation potential of wetland restoration. Reducing uncertainty in model predictions of annual CO2 and CH4 budgets is critical for including wetland restoration in Cap-and-Trade programs. We have developed and parameterized the Peatland Ecosystem Photosynthesis, Respiration, and Methane Transport model (PEPRMT) in a drained agricultural peatland and a restored wetland. Both ecosystem respiration (Reco) and CH4 production are a function of 2 soil carbon (C) pools (i.e. recently-fixed C and soil organic C), temperature, and water table height. Photosynthesis is predicted using a light use efficiency model. To estimate parameters we use a Markov Chain Monte Carlo approach with an adaptive Metropolis-Hastings algorithm. Multiple data streams are used to constrain model parameters including eddy covariance of CO2, 13CO2 and CH4, continuous soil respiration measurements and digital photography. Digital photography is used to estimate leaf area index, an important input variable for the photosynthesis model. Soil respiration and 13CO2 fluxes allow partitioning of eddy covariance data between Reco and photosynthesis. Partitioned fluxes of CO2 with associated uncertainty are used to parametrize the Reco and photosynthesis models within PEPRMT. Overall, PEPRMT model performance is high. For example, we observe high data-model agreement between modeled and observed partitioned Reco (r2 = 0.68; slope = 1; RMSE = 0.59 g C-CO2 m-2 d-1). Model validation demonstrated the model's ability to accurately predict annual budgets of CO2 and CH4 in a wetland system (within 14% and 1

  11. Quantifying Protein Synthesis and Degradation in Arabidopsis by Dynamic 13CO2 Labeling and Analysis of Enrichment in Individual Amino Acids in Their Free Pools and in Protein1[OPEN

    PubMed Central

    Fernie, Alisdair R.; Stitt, Mark

    2015-01-01

    Protein synthesis and degradation represent substantial costs during plant growth. To obtain a quantitative measure of the rate of protein synthesis and degradation, we supplied 13CO2 to intact Arabidopsis (Arabidopsis thaliana) Columbia-0 plants and analyzed enrichment in free amino acids and in amino acid residues in protein during a 24-h pulse and 4-d chase. While many free amino acids labeled slowly and incompletely, alanine showed a rapid rise in enrichment in the pulse and a decrease in the chase. Enrichment in free alanine was used to correct enrichment in alanine residues in protein and calculate the rate of protein synthesis. The latter was compared with the relative growth rate to estimate the rate of protein degradation. The relative growth rate was estimated from sequential determination of fresh weight, sequential images of rosette area, and labeling of glucose in the cell wall. In an 8-h photoperiod, protein synthesis and cell wall synthesis were 3-fold faster in the day than at night, protein degradation was slow (3%–4% d−1), and flux to growth and degradation resulted in a protein half-life of 3.5 d. In the starchless phosphoglucomutase mutant at night, protein synthesis was further decreased and protein degradation increased, while cell wall synthesis was totally inhibited, quantitatively accounting for the inhibition of growth in this mutant. We also investigated the rates of protein synthesis and degradation during leaf development, during growth at high temperature, and compared synthesis rates of Rubisco large and small subunits of in the light and dark. PMID:25810096

  12. Urinary Adiponectin Excretion

    PubMed Central

    von Eynatten, Maximilian; Liu, Dan; Hock, Cornelia; Oikonomou, Dimitrios; Baumann, Marcus; Allolio, Bruno; Korosoglou, Grigorios; Morcos, Michael; Campean, Valentina; Amann, Kerstin; Lutz, Jens; Heemann, Uwe; Nawroth, Peter P.; Bierhaus, Angelika; Humpert, Per M.

    2009-01-01

    OBJECTIVE Markers reliably identifying vascular damage and risk in diabetic patients are rare, and reports on associations of serum adiponectin with macrovascular disease have been inconsistent. In contrast to existing data on serum adiponectin, this study assesses whether urinary adiponectin excretion might represent a more consistent vascular damage marker in type 2 diabetes. RESEARCH DESIGN AND METHODS Adiponectin distribution in human kidney biopsies was assessed by immunohistochemistry, and urinary adiponectin isoforms were characterized by Western blot analysis. Total urinary adiponectin excretion rate was measured in 156 patients with type 2 diabetes who had a history of diabetic nephropathy and 40 healthy control subjects using enzyme-linked immunosorbent assay. Atherosclerotic burden was assessed by common carotid artery intima-media-thickness (IMT). RESULTS A homogenous staining of adiponectin was found on the endothelial surface of glomerular capillaries and intrarenal arterioles in nondiabetic kidneys, whereas staining was decreased in diabetic nephropathy. Low-molecular adiponectin isoforms (∼30–70 kDa) were detected in urine by Western blot analysis. Urinary adiponectin was significantly increased in type 2 diabetes (7.68 ± 14.26 vs. control subjects: 2.91 ± 3.85 μg/g creatinine, P = 0.008). Among type 2 diabetic patients, adiponectinuria was associated with IMT (r = 0.479, P < 0.001) and proved to be a powerful independent predictor of IMT (β = 0.360, P < 0.001) in multivariable regression analyses. In a risk prediction model including variables of the UK Prospective Diabetes Study coronary heart disease risk engine urinary adiponectin, but not the albumin excretion rate, added significant value for the prediction of increased IMT (P = 0.007). CONCLUSIONS Quantification of urinary adiponectin excretion appears to be an independent indicator of vascular damage potentially identifying an increased risk for vascular events. PMID:19509019

  13. Short-term carbon dynamics in a temperate heathland upon six years of exposure to elevated CO2 concentration, drought and warming: Evidence from an in-situ 13CO2 pulse-chase experiment

    NASA Astrophysics Data System (ADS)

    Ambus, P.; Reinsch, S.; Sárossy, Z.; Egsgaard, H.; Jakobsen, I.; Michelsen, A.; Schmidt, I.; Nielsen, P.

    2013-12-01

    An in-situ 13CO2 pulse-labeling experiment was carried out in a temperate heathland (8 oC MAT, 610 mm MAP) to study the impact on short-term carbon (C) allocation as affected by elevated CO2 concentration (+120 ppm), prolonged summer droughts (ca. -43 mm) and warming (+1 oC). The study was carried out six years after the climate treatments were initiated and took place in the early growing season in May in vegetation dominated by grasses, mainly Deschampsia flexuosa. Newly assimilated C (13C from the pulse-label) was traced into vegetation, soil and soil microorganisms and belowground respiration 1, 2 and 8 days after pulse-labeling. The importance of the microbial community in C utilization was investigated using 13C enrichment patterns in different microbial functional groups on the basis of phospholipid fatty acid (PLFA) profiles. Climate treatments did not affect microorganism abundance in soil or rhizosphere fractions in terms of total PLFA-C concentration. Elevated CO2 significantly reduced the abundance of gram-negative bacteria (17:0cy), but did not affect the abundance of decomposers (fungi and actinomycetes) in rhizosphere fractions. Drought favored the bacterial community in rhizosphere fractions whereas warming reduced the abundance of gram-negative bacteria (19:0cy) and changed the actinomycetes community (10Me16:0, 10Me18:0). Fastest and highest utilization of recently assimilated C was observed in rhizosphere associated gram-negative bacteria followed by gram-positive bacteria. The utilization of recently assimilated C by the microbial community was faster under elevated CO2 conditions compared to ambient. The 13C assimilation by green plant tissue and translocation to roots was significantly reduced by the extended summer drought. Under elevated CO2 conditions we observed an increased amount of 13C in the litter fraction. The assimilation of 13C by vegetation was not changed when the climate factors were applied in combination. The total amount of

  14. Absorption and excretion of black currant anthocyanins in humans and watanabe heritable hyperlipidemic rabbits.

    PubMed

    Nielsen, Inge Lise F; Dragsted, Lars O; Ravn-Haren, Gitte; Freese, Riitta; Rasmussen, Salka E

    2003-04-23

    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 (> or =6.6 and > or =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(max) (rabbits, approximately 30 min; humans, approximately 45 min). A food matrix effect was detected in rabbits, resulting in the absorption of a higher proportion of the anthocyanins from black currant juice than from an aqueous citric acid matrix. In humans the absorption and urinary excretion of anthocyanins from black currant juice were found to be proportional with dose and not influenced by the ingestion of a rice cake. In both species a larger proportion of the anthocyanin rutinosides than of the glucosides was absorbed, whereas the structure of the aglycon had no influence on the absorption and excretion. The anthocyanins had no effect in rabbits on the antioxidant capacity of plasma measured as Trolox equivalent antioxidant capacity and ferruc reducing ability of plasma. PMID:12696978

  15. Mathematical formulation of Tmax-Tstop method for LM-OSL and its experimental validation on α-Al2O3:C

    NASA Astrophysics Data System (ADS)

    Soni, Anuj; Mishra, D. R.

    2016-05-01

    A mathematical formulation and its experimental validation on α-Al2O3:C for evaluating the number of OSL components has been described. The method consists of various partial bleaching steps of LM-OSL curve and as a result, the peak position (Tmax) of the resultant curve shifts if the system contains multiple components. However, for single component system the peak position of the resultant curve doesn't change on partial bleaching for a phosphor obeying first order kinetics. The method has been theoretically formulated for single and multiple component system with different order of kinetics and validated experimentally on the commercial α-Al2O3:C OSL phosphor. The slope of the curve between shift in Tmax and bleaching time gives the number of the OSL components and measure of their closeness in terms of photoionization cross-section. Based on this result, the photoionization cross-section of the two embedded peaks in the LM-OSL curve of α-Al2O3:C were found to be 1.51 × 10-18 cm2 and 5.02 × 10-19 cm2 using CW-OSL and NL-OSL method.

  16. Quantifying the effect of Tmax extreme events on local adaptation to climate change of maize crop in Andalusia for the 21st century

    NASA Astrophysics Data System (ADS)

    Gabaldon, Clara; Lorite, Ignacio J.; Ines Minguez, M.; Lizaso, Jon; Dosio, Alessandro; Sanchez, Enrique; Ruiz-Ramos, Margarita

    2015-04-01

    Extreme events of Tmax can threaten maize production on Andalusia (Ruiz-Ramos et al., 2011). The objective of this work is to attempt a quantification of the effects of Tmax extreme events on the previously identified (Gabaldón et al., 2013) local adaptation strategies to climate change of irrigated maize crop in Andalusia for the first half of the 21st century. This study is focused on five Andalusia locations. Local adaptation strategies identified consisted on combinations of changes on sowing dates and choice of cultivar (Gabaldón et al., 2013). Modified cultivar features were the duration of phenological phases and the grain filling rate. The phenological and yield simulations with the adaptative changes were obtained from a modelling chain: current simulated climate and future climate scenarios (2013-2050) were taken from a group of regional climate models at high resolution (25 km) from the European Project ENSEMBLES (http://www.ensembles-eu.org/). After bias correcting these data for temperature and precipitation (Dosio and Paruolo, 2011; Dosio et al., 2012) crop simulations were generated by the CERES-maize model (Jones and Kiniry, 1986) under DSSAT platform, previously calibrated and validated. Quantification of the effects of extreme Tmax on maize yield was computed for different phenological stages following Teixeira et al. (2013). A heat stress index was computed; this index assumes that yield-damage intensity due to heat stress increases linearly from 0.0 at a critical temperature to a maximum of 1.0 at a limit temperature. The decrease of crop yield is then computed by a normalized production damage index which combines attainable yield and heat stress index for each location. Selection of the most suitable adaptation strategy will be reviewed and discussed in light of the quantified effect on crop yield of the projected change of Tmax extreme events. This study will contribute to MACSUR knowledge Hub within the Joint Programming Initiative on

  17. Urinary MDMA, MDA, HMMA, and HMA Excretion Following Controlled MDMA Administration to Humans

    PubMed Central

    Abraham, Tsadik T.; Barnes, Allan J.; Lowe, Ross H.; Spargo, Erin A. Kolbrich; Milman, Garry; Pirnay, Stephane O.; Gorelick, David A.; Goodwin, Robert S.; Huestis, Marilyn A.

    2011-01-01

    3,4-Methylenedioxymethamphetamine (MDMA), or ecstasy, is excreted as unchanged drug, 3,4-methylenedioxyamphetamine (MDA), and free and glucuronidated/sulfated 4-hydroxy-3-methoxymethamphetamine (HMMA), and 4-hydroxy-3-methoxyamphetamine (HMA) metabolites. The aim of this paper is to describe the pattern and timeframe of excretion of MDMA and its metabolites in urine. Placebo, 1.0 mg/kg, and 1.6 mg/kg oral MDMA doses were administered double-blind to healthy adult MDMA users on a monitored research unit. All urine was collected, aliquots were hydrolyzed, and analytes quantified by gas chromatography–mass spectrometry. Median Cmax, Tmax, ratios, first and last detection times, and detection rates were determined. Sixteen participants provided 916 urine specimens. After 1.6 mg/kg, median Cmax were 21,470 (MDMA), 2229 (MDA), 20,793 (HMMA), and 876 ng/mL (HMA) at median Tmax of 13.9, 23.0, 9.2 and 23.3 h. In the first 24 h, 30.2–34.3% total urinary excretion occurred. HMMA last detection exceeded MDMA’s by more than 33 h after both doses. Identification of HMMA as well as MDMA increased the ability to identify positive specimens but required hydrolysis. These MDMA, MDA, HMMA, and HMA pharmacokinetic data may be useful for interpreting workplace, drug treatment, criminal justice, and military urine drug tests. Measurement of urinary HMMA provides the longest detection of MDMA exposure yet is not included in routine monitoring procedures. PMID:19874650

  18. Viscous food matrix influences absorption and excretion but not metabolism of blackcurrant anthocyanins in rats.

    PubMed

    Walton, Michaela C; Hendriks, Wouter H; Broomfield, Anne M; McGhie, Tony 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 approximately 250 mg total ACNs per kilogram BW. Blood, urine, digesta, and tissue samples of the stomach, jejunum, and colon were subsequently collected at 0.25, 0.5, 1, 2, 3, 7, and 24 h. Identification and quantification of ACNs were carried out by Reversed phase-high-performance liquid chromatography (RP-HPLC) and liquid chromatography-mass spectrometry (LC-MS). Four major ACNs were present in the blackcurrant extract: delphinidin 3-O-glucoside, delphinidin 3-O-rutinoside, cyanidin 3-O-glucoside, and cyanidin 3-O-rutinoside. In plasma, the 4 ACNs of blackcurrant were identified and quantified. The time to reach maximal total ACN plasma concentration (C(max) BcACN/water = 0.37 +/- 0.07 micromol/L; C(max) BcACN/oatmeal = 0.20 +/- 0.05 micromol/L) occurred faster after BcACN/water (t(max)= 0.25 h), than after BcACN/oatmeal administration (t(max)= 1.0 h). In digesta and tissue samples, the 4 original blackcurrant ACNs were detected. The relative concentration of rutinosides in the digesta increased during their passage through the gastrointestinal tract, while the glucosides decreased. Maximum ACN excretion in urine occurred later after BcACN/oatmeal than after BcACN/water administration (3 compared with 2 h). The 4 original ACNs of blackcurrant in their unchanged form, as well as several metabolites, were identified in the urine samples of both groups. The simultaneous intake of food affects ACN absorption and excretion in the urine, but not metabolism.

  19. Preparation of an amorphous sodium furosemide salt improves solubility and dissolution rate and leads to a faster Tmax after oral dosing to rats.

    PubMed

    Nielsen, Line Hagner; Gordon, Sarah; Holm, René; Selen, Arzu; Rades, Thomas; Müllertz, Anette

    2013-11-01

    crystalline free acid, respectively. The promising properties of the amorphous salt in vitro were further evaluated in an in vivo study, where solid dosage forms of the amorphous salt, amorphous and crystalline free acid and a solution of furosemide were administered orally to rats. The amorphous salt exhibited a significantly faster Tmax compared to the solution and amorphous and crystalline free acid. Cmax for the solution was significantly higher compared to the three furosemide forms. No significant difference was found in AUC and absolute bioavailability for the solution, crystalline free acid and the two amorphous forms of furosemide. It can be concluded that the higher IDR and higher apparent solubility of the amorphous salt resulted in a faster Tmax compared to the amorphous and crystalline free acid. PMID:24075980

  20. Absorption, Distribution, Excretion, and Pharmacokinetics of 14C-Pyronaridine Tetraphosphate in Male and Female Sprague-Dawley Rats

    PubMed Central

    Park, Sang Hyun; Pradeep, Kannampalli

    2010-01-01

    The main objective of this investigation was to determine the absorption, distribution, excretion, and pharmacokinetics of the antimalarial drug pyronaridine tetraphosphate (PNDP) in Sprague-Dawley rats. Following oral administration of a single dose (10 mg/Kg) of 14C-PNDP, it was observed that the drug was readily absorbed from the small intestine within 1 hour following oral administration and was widely distributed in most of the tissues investigated as determined from the observed radioactivity in the tissues. The peak value of the drug in the blood was reached at around 8 hours postadministration, and radioactivity was detected in most of the tissues from 4 hours onwards. 14C-PNDP showed a poor permeability across the blood-brain barrier, and the absorption, distribution, and excretion of 14C-PNDP were found to be gender-independent as both male and female rats showed a similar pattern of radioactivity. Excretion of the drug was predominantly through the urine with a peak excretion post 24 hours of administration. A small amount of the drug was also excreted in the feces and also in the breath. It was found that the Cmax, AUC (0-inf), and Tmax values were similar to those observed in the Phase II clinical trials of pyronaridine/artesunate (Pyramax) conducted in Uganda. PMID:20379367

  1. Ammonia excretion by Azobacter chroococcum

    SciTech Connect

    Narula, N.; Lakshminarayana, K.; Tauro, P.

    1981-02-01

    In recent years, research has focused attention on the development of biological systems for nitrogen fixation. In this report, two strains of Azotobacter chroococcum are identified which can excrete as much as 45 mg ammonia/ml of the culture broth in a sucrose supplemented synthetic medium.

  2. Cytomegalovirus excretion in gnotobiotic pigs.

    PubMed Central

    Edington, N.; Watt, R. G.; Plowright, W.

    1976-01-01

    Germ-free piglets were infected intranasally with porcine cytomegalovirus (PCMV) at 1 day (group A) or 3 weeks of age (group B). Viraemia and virus excretion by the nasal, pharyngeal and conjunctival routes was studied up to the time of death or to 12 weeks. Virus was also sought in tissues at death or at slaughter, as well as in a few urine samples. Viraemia was detected in group A between days 5 and 19 after infection and in group B between days 14 and 16 inclusive. The chief route of virus excretion was the nasal mucosa, followed by the pharynx and conjunctiva; the maximal duration of excretion by these routes was 32, 25 and 14 days for pigs of group A and 9, 7 and 4 days for group B. The quantity of virus was also greater in the former group, of which died of generalized PCMV infection. A viruria was demonstrated in 2 animals. Antibody detectable in indirect immunofluorescence (IIF) tests appeared towards the end of the third week, reaching maximal titres at 5 to 7 weeks after infection. The mean peak titre of antibody in group B was lower than in group A. Corticosteroid treatment at days 56--62 after infection resulted in some recrudescence of virus excretion, accompanied in group B by about a twofold increase in IIF antibody. PCMV was isolated in cultures of lung macrophages from 4 of 7 animals killed at about 12 weeks after inoculation. PMID:185292

  3. Gonadotropin excretion and body composition.

    PubMed

    Penny, R; Goldstein, I P; Frasier, S D

    1978-02-01

    Urinary follicle stimulating hormone (FSH) and luteinizing hormone (LH) excretion was correlated with calculated total body water (TBW) and body fat (BF) in 140 normal girls and 142 normal boys, ages 3 to 16 years. In girls, there was a significant increase in gonadotropin excretion at the time of a significant increase in BF as a percent of body weight and decrease in TBW as a percent of body weight. Pubertal changes in body composition were seen in girls at the same chronological age and stage of puberty as increased gonadotropin excretion. Similar findings were observed in boys. Pubertal changes in body composition (an increase in TBW as a percent of body weight and decrease of BF as a percent of body weight) accompanied significantly increased gonadotropin excretion. Both developmental changes were seen at the same chronological age and stage of puberty. Our findings are consistent with the hypothesis that characteristic changes in body composition as well as the other hallmarks of puberty, including menarche in girls, result from increased gonadotropin and gonadal steroid secretion. They do not support the hypothesis that changes of body composition trigger increased hypothalamic function and hormone secretion leading to the subsequent events of puberty. PMID:634687

  4. Human pharmacology of ayahuasca: subjective and cardiovascular effects, monoamine metabolite excretion, and pharmacokinetics.

    PubMed

    Riba, Jordi; Valle, Marta; Urbano, Gloria; Yritia, Mercedes; Morte, Adelaida; Barbanoj, Manel J

    2003-07-01

    The effects of the South American psychotropic beverage ayahuasca on subjective and cardiovascular variables and urine monoamine metabolite excretion were evaluated, together with the drug's pharmacokinetic profile, in a double-blind placebo-controlled clinical trial. This pharmacologically complex tea, commonly obtained from Banisteriopsis caapi and Psychotria viridis, combines N,N-dimethyltryptamine (DMT), an orally labile psychedelic agent showing 5-hydroxytryptamine2A agonist activity, with monoamine oxidase (MAO)-inhibiting beta-carboline alkaloids (harmine, harmaline, and tetrahydroharmine). Eighteen volunteers with prior experience in the use of psychedelics received single oral doses of encapsulated freeze-dried ayahuasca (0.6 and 0.85 mg of DMT/kg of body weight) and placebo. Ayahuasca produced significant subjective effects, peaking between 1.5 and 2 h, involving perceptual modifications and increases in ratings of positive mood and activation. Diastolic blood pressure showed a significant increase at the high dose (9 mm Hg at 75 min), whereas systolic blood pressure and heart rate were moderately and nonsignificantly increased. Cmax values for DMT after the low and high ayahuasca doses were 12.14 ng/ml and 17.44 ng/ml, respectively. Tmax (median) was observed at 1.5 h after both doses. The Tmax for DMT coincided with the peak of subjective effects. Drug administration increased urinary normetanephrine excretion, but, contrary to the typical MAO-inhibitor effect profile, deaminated monoamine metabolite levels were not decreased. This and the negligible harmine plasma levels found suggest a predominantly peripheral (gastrointestinal and liver) site of action for harmine. MAO inhibition at this level would suffice to prevent first-pass metabolism of DMT and allow its access to systemic circulation and the central nervous system.

  5. Predicting nitrogen excretion from cattle.

    PubMed

    Reed, K F; Moraes, L E; Casper, D P; Kebreab, E

    2015-05-01

    Manure nitrogen (N) from cattle production facilities can lead to negative environmental effects, such as contribution to greenhouse gas emissions, leaching and runoff to aqueous ecosystems leading to eutrophication, and acid rain. To mitigate these effects and to improve the efficiency of N use, accurate prediction of N excretion and secretions are required. A genetic algorithm was implemented to select models to predict fecal, urinary, and total manure N excretions, and milk N secretions from 3 classes of animals: lactating dairy cows, heifers and dry cows, and steers. Two tiers of model classes were developed for each category of animals based on model input requirements. A total of 6 models for heifers and dry cows and steers and an additional 2 models for lactating dairy cattle were developed. Evaluation of the models using K-fold cross validation based on all data and using the most recent 6 yr of data showed better prediction for total manure N and fecal N compared with urinary N excretion, which was the most variable response in the database. Compared with extant models from the literature, the models developed in this study resulted in a significant improvement in prediction error for fecal and urinary N excretions from lactating cows. For total manure production by lactating cows, extant and new models were comparable in their prediction ability. Both proposed and extant models performed better than the prediction methods used by the US Environmental Protection Agency for the national inventory of greenhouse gases. Therefore, the proposed models are recommended for use in estimation of manure N from various classes of animals. PMID:25747829

  6. Predicting nitrogen excretion from cattle.

    PubMed

    Reed, K F; Moraes, L E; Casper, D P; Kebreab, E

    2015-05-01

    Manure nitrogen (N) from cattle production facilities can lead to negative environmental effects, such as contribution to greenhouse gas emissions, leaching and runoff to aqueous ecosystems leading to eutrophication, and acid rain. To mitigate these effects and to improve the efficiency of N use, accurate prediction of N excretion and secretions are required. A genetic algorithm was implemented to select models to predict fecal, urinary, and total manure N excretions, and milk N secretions from 3 classes of animals: lactating dairy cows, heifers and dry cows, and steers. Two tiers of model classes were developed for each category of animals based on model input requirements. A total of 6 models for heifers and dry cows and steers and an additional 2 models for lactating dairy cattle were developed. Evaluation of the models using K-fold cross validation based on all data and using the most recent 6 yr of data showed better prediction for total manure N and fecal N compared with urinary N excretion, which was the most variable response in the database. Compared with extant models from the literature, the models developed in this study resulted in a significant improvement in prediction error for fecal and urinary N excretions from lactating cows. For total manure production by lactating cows, extant and new models were comparable in their prediction ability. Both proposed and extant models performed better than the prediction methods used by the US Environmental Protection Agency for the national inventory of greenhouse gases. Therefore, the proposed models are recommended for use in estimation of manure N from various classes of animals.

  7. Salt excretion in Suaeda fruticosa.

    PubMed

    Labidi, Nehla; Ammari, Manel; Mssedi, Dorsaf; Benzerti, Maali; Snoussi, Sana; Abdelly, C

    2010-09-01

    Suaeda fruticosa is a perennial "includer" halophyte devoid of glands or trichomes with a strong ability of accumulating and sequestrating Na(+) and Cl(-). We were interested in determining whether leaf cuticle salt excretion could be involved as a further mechanism in salt response of this species after long-term treatment with high salinity levels. Seedlings had been treated for three months with seawater (SW) diluted with tap water (0, 25, 50 and 75% SW). Leaf scanning electron microscopy revealed a convex adaxial side sculpture and a higher accumulation of saline crystals at the lamina margin, with a large variability on repartition and size between treatments. No salt gland or salt bladder was found. Threedimensional wax decorations were the only structures found on leaf surface. Washing the leaf surface with water indicated that sodium and chloride predominated in excreted salts, and that potassium was poorly represented. Optimal growth of whole plant was recorded at 25% SW, correlating with maximum Na(+) and Cl(-) absolute secretion rate. The leaves of plants treated with SW retained more water than those of plants treated with tap water due to lower solute potential, especially at 25% SW. Analysis of compatible solute, such as proline, total soluble carbohydrates and glycinebetaine disclosed strong relationship between glycinebetaine and osmotic potential (r = 0.92) suggesting that tissue hydration was partly maintained by glycinebetaine accumulation. Thus in S. fruticosa , increased solute accumulation associated with water retention, and steady intracellular ion homeostasis confirms the "includer" strategy of salt tolerance previously demonstrated. However, salt excretion at leaf surface also participated in conferring to this species a capacity in high salinity tolerance.

  8. Purine and pyrimidine excretion in psoriasis

    PubMed Central

    Simmonds, H. A.; Bowyer, A.

    1974-01-01

    1 Urinary purine excretion has been investigated in two healthy controls and two patients with psoriasis, one a hyperuricaemic, one a normouricaemic. No difference was detected between the patients and controls. Therapy with allopurinol effectively lowered blood and urinary uric acid levels and produced a deficit in total urinary oxypurine excretion in both controls and patients with psoriasis. The concomitant increase in xanthine excretion was greater than the increase in hypoxanthine excretion and xanthine/hypoxanthine ratios (average 0.70 and 1.0 prior to therapy) were increased by allopurinol to an average of 3.0 and 3.8 respectively in the two groups. Allopurinol also reduced the excretion of 8-hydroxy-7-methyl guanine but no effect on the excretion levels of other minor purine bases was noted. 2 Allopurinol was metabolized similarly by both patients and controls, 84% of the administered allopurinol being accounted for as urinary metabolites. 74% of the drug in the urine was excreted as oxipurinol, 26% as unchanged allopurinol plus allopurinol riboside, the remainder being oxipurinol riboside. 3 Pseudouridine excretion in 25 healthy controls was 86.5 ± 17.8 mg/24 hours. Pseudouridine excretion was not excessive in the patients with psoriasis and was not altered by allopurinol therapy. 4 No abnormality or difference in purine or pyrimidine excretion in either patient was detected prior to or during therapy which could be related to the epidermal lesion. PMID:22454896

  9. [Renal calcium excretion and urolithiasis].

    PubMed

    Aruga, Seiji; Honma, Yukio

    2011-10-01

    Patients with urolithiasis have been increasing in the world, especially morbidity of calcium nephrolithiasis has been increasing in the advanced countries. The changes in the environmental factors including alternation of diet are said to be associated with the increment of morbidity of kidney stone. Idiopathic hypercalciuria is one of the most important risk factor of calcium nephrolithiasis and is classified into absorptive, resorptive, and renal leak. Though the origins of these three types of hypercalciuria are different, increased bone resorption and increased calcium absorption from gut tend to be observed simultaneously. Not only genetic abnormalities in the proteins which are involved in calcium metabolisms but environmental factors such as high sodium intake and chronic acid load caused by increased ingestion of animal protein have been considered to be associated with increased urinary calcium excretion. Renal metabolisms of oxalate and phosphate which are important compositions of calcium containing stone, uric acid as a promoter and citrate as a inhibitor of nephrolithiasis are also described.

  10. Synergism between maggot excretions and antibiotics.

    PubMed

    Cazander, Gwendolyn; Pawiroredjo, Janity S; Vandenbroucke-Grauls, Christina M J E; Schreurs, Marco W J; Jukema, Gerrolt N

    2010-01-01

    Maggots are successfully used to treat severe, infected wounds. This study investigated whether maggot excretions/secretions influence the antibacterial activity of different antibiotics. Minimal inhibitory concentrations and minimal bactericidal concentrations (MBC) were determined of gentamicin and flucloxacillin for Staphylococcus aureus, of penicillin for Streptococcus pyogenes, of amoxicillin and vancomycin for Enterococcus faecalis, of gentamicin for Enterobacter cloacae, and of gentamicin, tobramycin, and ciprofloxacin for Pseudomonas aeruginosa by checkerboard titration. A range of concentrations of antibiotics in combination with excretions/secretions was examined to investigate the potential of maggot excretions/secretions to affect antibacterial activity. The results showed a dose-dependent increase of the antibacterial effect of gentamicin in the presence of excretions/secretions on S. aureus. Minimal concentrations and MBC of gentamicin decreased, respectively, 64- and 32-fold. The MBC of flucloxacillin and excretions/secretions against S. aureus were also decreased. The other antibiotic and excretions/secretions combinations exerted an indifferent effect. Excretions/secretions alone did not have any antibacterial effect. The synergism between gentamicin and maggot excretions/secretions could be of direct importance in clinical practice, because it could allow the use of lower doses of gentamicin and thus minimize the risk of gentamicin-related side effects.

  11. Salivary and urinary excretion and plasma-saliva concentration ratios of isoniazid in the presence of Co-administered ciprofloxacin.

    PubMed

    Ofoefule, Sabinus I; Obodo, Chioma E; Orisakwe, Orish E; Afonne, Johnson O; Ilondu, Ndidiamaka A; Agbasi, Patrick U; Anusiem, Chikere A; Maduka, Steve O; Ilo, Cajetan E

    2002-01-01

    Salivary and urinary excretion and plasma-saliva concentration ratios of isoniazid (INH) in the absence and presence of ciprofloxacin (CP) were investigated in healthy female volunteers. Results obtained indicated an absorption form of interaction between INH and CP. This led to delay in gastric emptying and onset of absorption of INH in the upper part of the gastrointestinal tract, resulting in a corresponding delay in the onset of salivary and urinary excretion of the drugs. There was a 1-hour reduction in the time to attain peak saliva concentration of INH (tmax), an insignificant difference in peak saliva concentration (Cmax), and a significant (P = 0.05) increase in AUC(0-24h) of INH in the presence of CP. Cumulative amount of INH excreted in the urine increased approximately 38% in the presence of CP. The calculated plasma-saliva concentration ratios of INH were reduced in the presence of CP and were slightly lower than the experimental values. This indicates increased amount of the drug secreted into saliva in the presence of CP and possible buccal partitioning of the drug. Overall, results of the current study indicate that CP delayed the onset but not the extent of INH absorption. Therefore, concurrent administration of the two drugs was considered relatively safe, and the absorption interaction that may have occurred may not be of reasonable clinical consequence.

  12. The effects of uphill vs. level-grade high-intensity interval training on VO2max, Vmax, V(LT), and Tmax in well-trained distance runners.

    PubMed

    Ferley, Derek D; Osborn, Roy W; Vukovich, Matthew D

    2013-06-01

    Uphill running represents a frequently used and often prescribed training tactic in the development of competitive distance runners but remains largely uninvestigated and unsubstantiated as a training modality. The purpose of this investigation included documenting the effects of uphill interval training compared with level-grade interval training on maximal oxygen consumption (VO2max), the running speed associated with VO2max (Vmax), the running speed associated with lactate threshold (V(LT)), and the duration for which Vmax can be sustained (Tmax) in well-trained distance runners. Thirty-two well-trained distance runners (age, 27.4 ± 3.8 years; body mass, 64.8 ± 8.9 kg; height, 173.6 ± 6.4 cm; and VO2max, 60.9 ± 8.5 ml·min(-1)·kg(-1)) received assignment to an uphill interval training group (G(Hill) = 12), level-grade interval training group (G(Flat) = 12), or control group (G(Con) = 8). G(Hill) and G(Flat) completed 12 interval and 12 continuous running sessions over 6 weeks, whereas G(Con) maintained their normal training routine. Pre- and posttest measures of VO2max, Vmax, V(LT), and Tmax were used to assess performance. A 3 × 2 repeated measures analysis of variance was performed for each dependent variable and revealed a significant difference in Tmax in both G(Hill) and G(Flat) (p < 0.05). With regard to running performance, the results indicate that both uphill and level-grade interval training can induce significant improvements in a run-to-exhaustion test in well-trained runners at the speed associated with VO2max but that traditional level-grade training produces greater gains.

  13. The relationship between kallikrein and water excretion and the conditional relationship between kallikrein and sodium excretion.

    PubMed Central

    Mills, I H; Ward, P E

    1975-01-01

    1. The renal kallikrein-kinin system has previously been linked with renal control of sodium and water excretion. The present investigations were carried out to examine more closely these relationships. 2. In physiological studies with rabbits, urinary kallikrein was measured by a modification of the [3-H]TAME method. 3. With rabbits on free sodium and water intake, urinary kallikrein was positively correlated with both sodium and water excretion. Kallikrein excretion was also negatively correlated with urinary osmolality. 4. In rabbits on chronic high and low sodium diets, urinary kallikrein was positively correlated with urinary volume but not with sodium excretion. 5. In rabbits held to a constant fluid intake but with sodium intake changed, urinary kallikrein was not correlated with sodium excretion. 6. These results indicate that the positive correlation of kallikrein excretion with sodium excretion under conditions of free sodium and water intake may be only secondary to the positive relationship of kallikrein excretion with urinary volume. 7. The results of the present investigations do not support the hypothesis that the renal kallikrein-kinin system is necessarily involved in renal control of sodium excretion under normal conditions but it is where a change in sodium intake leads to a change in fluid intake and consequently of urinary volume. 8. In the above experiments, urinary kallikrein was always positively correlated with urinary volume and negatively correlated with urinary osmolality. This may indicate a functional relationship between renal kallikrein and water excretion. PMID:1133793

  14. Maggot excretions affect the human complement system.

    PubMed

    Cazander, Gwendolyn; Schreurs, Marco W J; Renwarin, Lennaert; Dorresteijn, Corry; Hamann, Dörte; Jukema, Gerrolt N

    2012-01-01

    The complement system plays an important role in the activation of the inflammatory response to injury, although inappropriate complement activation (CA) can lead to severe tissue damage. Maggot therapy is successfully used to treat infected wounds. In this study, we hypothesized that maggot excretions/secretions influence CA in order to modulate the host's inflammatory response. Therefore, the effect of maggot excretions on CA was investigated in preoperatively and postoperatively obtained sera from patients. Our results show that maggot excretions reduce CA in healthy and postoperatively immune-activated human sera up to 99.9%, via all pathways. Maggot excretions do not specifically initiate or inhibit CA, but break down complement proteins C3 and C4 in a cation-independent manner and this effect proves to be temperature tolerant. This study indicates a CA-reducing substrate that is already successfully used in clinical practice and may explain part of the improved wound healing caused by maggot therapy. Furthermore, the complement activation-reducing substance present in maggot excretions could provide a novel treatment modality for several diseases, resulting from an (over)active complement system.

  15. Enhancement of radiopharmaceutical excretion by chemical interventions

    SciTech Connect

    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)

  16. Clinical study of urinary excretion of Ga-67

    SciTech Connect

    Nakano, S.; Hasegawa, Y.; Ibuka, K.; Hashizume, T.; Noguchi, A.; Kojima, J.; Sasakuma, F.; Ishigami, S. )

    1990-04-01

    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.

  17. Urinary excretion of Iopamidol following intrathecal administration.

    PubMed

    Pitrè, D; Zingales, M F; Trevisan, C

    1983-01-01

    No iodinated compound other than Iopamidol was found in the urine of subjects who received intrathecal injection of 10 ml of Iopamiro "300". The compound was neither metabolized nor altered in its optical configuration and urinary iodide content was always in the normal range. Between 72 and 85% of injected Iopamidol was excreted within 72 h of injection.

  18. Urine protein excretion and swimming events.

    PubMed

    Poortmans, J R; Engels, M F; Sellier, M; Leclercq, R

    1991-07-01

    To determine total urinary protein, albumin (ALB), and beta 2-microglobulin (beta 2m) excretion rates in relation to different speeds, 12 males were studied while swimming distances of 100, 600, and 2,000 m at maximal speed. Venous blood lactate concentrations rose to 16.1, 11.6, and 4.5 mmol.l-1 after the 100, 600, and 2,000 m events, while plasma volumes were reduced by 11.3, 7.7, and 5.5%, respectively. ALB urine excretion increased to 110-120 micrograms.min-1 after the 100 and 600 m swims and to 56 micrograms.min-1 after 2,000 m (resting values: 9 micrograms.min-1). In the meantime, the beta 2m excretion rate increased 21 and 10 times the resting values, respectively, for the two shorter swims, with no change for the longer one. Progressive plasma volume reduction was associated with the increase of the protein excretion rate. As evidenced by the creatinine clearance, the glomerular filtration rate did not change for the 100 m swim but dropped by 23 and 35% for the 600 and 2,000 m ones, respectively. On the other hand, the ALB clearance increases were elevated for the three swims, while the beta 2m clearance increases were inversely related to the swimming speeds. The data showed a relationship between the rate of protein excretion and the speed of the swim, and the reduction of plasma volume. The findings could indicate a renal glomerular alteration, with an additional dysfunction of the tubular reabsorption process when the exercise load is high during swimming events. PMID:1921676

  19. Effects of methylxanthines on urinary prostaglandin E excretion in rats.

    PubMed

    Takeuchi, K; Kogo, H; Aizawa, Y

    1981-04-01

    Effect of methylxanthines (theophylline, theobromine and caffeine) on urinary prostaglandin E (PGE) excretion in male rats was studied. Oral administration of xanthines significantly increased the urinary excretion of PGE. Dose-response studies showed that the maximal excretion of urinary PGE and water was obtained by administration of theophylline (50 mg/kg), where the increase in PGE was about 20 times that of the control. The excretion of urinary sodium, potassium and chloride was also markedly increased by xanthines, particularly, theophylline. Increases in urinary PGE excretion, urine volume and electrolytes excretion were inhibited by 10 mg/kg of indomethacin administered prior to theophylline. The increase of urinary PGE excretion after theophylline administration (50 mg/kg) preceded increases in water and sodium excretion. These results suggest that renal PGE mediates, at least in part, the diuretic effect of theophylline. PMID:7311144

  20. Urinary excretion of arsenic following rice consumption.

    PubMed

    Meharg, A A; Williams, P N; Deacon, C M; Norton, G J; Hossain, M; Louhing, D; Marwa, E; Lawgalwi, Y; Taggart, M; Cascio, C; Haris, P

    2014-11-01

    Patterns of arsenic excretion were followed in a cohort (n = 6) eating a defined rice diet, 300 g per day d.wt. where arsenic speciation was characterized in cooked rice, following a period of abstinence from rice, and other high arsenic containing foods. A control group who did not consume rice were also monitored. The rice consumed in the study contained inorganic arsenic and dimethylarsinic acid (DMA) at a ratio of 1:1, yet the urine speciation was dominated by DMA (90%). At steady state (rice consumption/urinary excretion) ∼40% of rice derived arsenic was excreted via urine. By monitoring of each urine pass throughout the day it was observed that there was considerable variation (up to 13-fold) for an individual's total arsenic urine content, and that there was a time dependent variation in urinary total arsenic content. This calls into question the robustness of routinely used first pass/spot check urine sampling for arsenic analysis. PMID:25145278

  1. Chylomicrons enhance endotoxin excretion in bile.

    PubMed Central

    Read, T E; Harris, H W; Grunfeld, C; Feingold, K R; Calhoun, M C; Kane, J P; Rapp, J H

    1993-01-01

    Chylomicrons prevent endotoxin toxicity and increase endotoxin uptake by hepatocytes. As a consequence, less endotoxin is available to activate macrophages, thereby reducing tumor necrosis factor secretion. To determine whether the chylomicron-mediated increase in hepatocellular uptake of endotoxin results in increased endotoxin excretion into bile, we examined bile after endotoxin administration. A sublethal dose (7 micrograms/kg) of 125I-endotoxin was incubated with either rat mesenteric lymph containing nascent chylomicrons (500 mg of chylomicron triglyceride per kg of body weight) or an equal volume of normal saline (controls) for 3 h and then infused into male Sprague-Dawley rats. Bile samples were collected via a common bile duct catheter for 24 h. Infusion of endotoxin incubated with chylomicrons increased biliary excretion of endotoxin by 67% at 3 h (P < or = 0.006) and by 20% at 24 h (P < or = 0.01) compared with infusion of endotoxin incubated in saline. Endotoxin activity, as measured by the Limulus assay, was not detected in the bile of test animals. However, endotoxin activity was detected after hot phenol-water extraction of bile, demonstrating that endotoxin is inactive in the presence of bile but retains bioactivity after hepatic processing. Since the majority of an intravenous endotoxin load has been shown to be cleared by the liver, acceleration of hepatocyte clearance and biliary excretion of endotoxin may represent a component of the mechanism by which chylomicrons protect against endotoxin-induced lethality. PMID:8335381

  2. Urinary excretion of arsenic following rice consumption.

    PubMed

    Meharg, A A; Williams, P N; Deacon, C M; Norton, G J; Hossain, M; Louhing, D; Marwa, E; Lawgalwi, Y; Taggart, M; Cascio, C; Haris, P

    2014-11-01

    Patterns of arsenic excretion were followed in a cohort (n = 6) eating a defined rice diet, 300 g per day d.wt. where arsenic speciation was characterized in cooked rice, following a period of abstinence from rice, and other high arsenic containing foods. A control group who did not consume rice were also monitored. The rice consumed in the study contained inorganic arsenic and dimethylarsinic acid (DMA) at a ratio of 1:1, yet the urine speciation was dominated by DMA (90%). At steady state (rice consumption/urinary excretion) ∼40% of rice derived arsenic was excreted via urine. By monitoring of each urine pass throughout the day it was observed that there was considerable variation (up to 13-fold) for an individual's total arsenic urine content, and that there was a time dependent variation in urinary total arsenic content. This calls into question the robustness of routinely used first pass/spot check urine sampling for arsenic analysis.

  3. Ammonia excretion in aquatic and terrestrial crabs.

    PubMed

    Weihrauch, Dirk; Morris, Steve; Towle, David W

    2004-12-01

    The excretory transport of toxic ammonia across epithelia is not fully understood. This review presents data combined with models of ammonia excretion derived from studies on decapod crabs, with a view to providing new impetus to investigation of this essential issue. The majority of crabs preserve ammonotely regardless of their habitat, which varies from extreme hypersaline to freshwater aquatic environments, and ranges from transient air exposure to obligate air breathing. Important components in the excretory process are the Na+/K+(NH4+)-ATPase and other membrane-bound transport proteins identified in many species, an exocytotic ammonia excretion mechanism thought to function in gills of aquatic crabs such as Carcinus maenas, and gaseous ammonia release found in terrestrial crabs, such as Geograpsus grayi and Ocypode quadrata. In addition, this review presents evidence for a crustacean Rhesus-like protein that shows high homology to the human Rhesus-like ammonia transporter both in its amino acid sequence and in its predicted secondary structure. PMID:15579545

  4. Renal protein excretion after exercise in man.

    PubMed

    Poortmans, J R; Rampaer, L; Wolfs, J C

    1989-01-01

    Thirteen men were submitted to graded exhaustive cycle exercise to determine the kinetics of proteinuria in the recovery period. Venous blood samples were analysed for haematocrit, lactate, creatinine, total protein and albumin for 1 h following exercise. Urine samples were collected during a 3-h recovery period. Total protein, albumin, and creatinine levels were determined for these samples. Total protein and albumin urinary excretion increased to 581 and 315 micrograms min-1, respectively, at the end of the 1st h of recovery as compared to 42 and 15 micrograms.min-1 for resting values. Plasma volume returned to pre-exercise levels between 30 and 60 min after cessation of exercise, while urinary total protein and albumin content still remained above the resting values for the following 2 h. Both post-exercise urinary total protein and albumin excretion followed a logarithmic decline with the same half-life of 54 min, thus requiring about 4 h to regain resting values. The reduction of plasma volume and the degree of dehydration do not seem to be involved in the process. The present study indicates the delayed recovery of protein handling by the kidney, as compared with other biochemical parameters, and provides accurate information on the kinetics of post-exercise proteinuria. PMID:2759073

  5. Effect of monofluoroacetate on renal H+ excretion in the rat.

    PubMed

    Simonnet, H; Gauthier, C; Pellet, M V

    1979-05-01

    In order to investigate the effect of monofluoroacetate (MFA) on renal H+ excretion, anesthetized rats under mannitol diuresis were given intraperitoneally MFA and some of the acido-basic status parameters were determined. Urinary pH and pCO2 did not change after MFA administration, while urinary flow rate increased. MFA induced a decrease in H+ net excretion and in ammonia excretion. Titratable acidity did not change significantly within the experiment.

  6. Modeling single cell antibody excretion on a biosensor.

    PubMed

    Stojanović, Ivan; Baumgartner, Wolfgang; van der Velden, Thomas J G; Terstappen, Leon W M M; Schasfoort, Richard B M

    2016-07-01

    We simulated, using Comsol Multiphysics, the excretion of antibodies by single hybridoma cells and their subsequent binding on a surface plasmon resonance imaging (SPRi) sensor. The purpose was to confirm that SPRi is suitable to accurately quantify antibody (anti-EpCAM) excretion. The model showed that antibody loss by diffusion away from the sensor was less than 1%. Unexpectedly, more than 99% of the excreted antibodies were captured on the sensor. These data prove the remarkable phenomenon that the SPRi output of cellular antibody excretion and its subsequent binding, performed under the conditions described here, is directly usable for quantification of single cell antibody production rates. PMID:27040182

  7. Modeling single cell antibody excretion on a biosensor.

    PubMed

    Stojanović, Ivan; Baumgartner, Wolfgang; van der Velden, Thomas J G; Terstappen, Leon W M M; Schasfoort, Richard B M

    2016-07-01

    We simulated, using Comsol Multiphysics, the excretion of antibodies by single hybridoma cells and their subsequent binding on a surface plasmon resonance imaging (SPRi) sensor. The purpose was to confirm that SPRi is suitable to accurately quantify antibody (anti-EpCAM) excretion. The model showed that antibody loss by diffusion away from the sensor was less than 1%. Unexpectedly, more than 99% of the excreted antibodies were captured on the sensor. These data prove the remarkable phenomenon that the SPRi output of cellular antibody excretion and its subsequent binding, performed under the conditions described here, is directly usable for quantification of single cell antibody production rates.

  8. Pharmacokinetics, tissue distribution and excretion of isoalantolactone and alantolactone in rats after oral administration of Radix Inulae extract.

    PubMed

    Xu, Renjie; Zhou, Guisheng; Peng, Ying; Wang, Mengyue; Li, Xiaobo

    2015-04-28

    Radix Inulae is endemic to China and has been used in traditional medicine to treat upper body pain, emesis and diarrhoea, and to eliminate parasites. Here, an UPLC-MS/MS method was developed and applied to study the pharmacokinetics, distribution and excretion of isoalantolactone and alantolactone, which are two main active sesquiterpene lactones in Radix Inulae, in Sprague-Dawley rats following oral administration of total Radix Inulae extract. Isoalantolactone, alantolactone and osthole (internal standard) were prepared using acetonitrile precipitation, and the separation of isoalantolactone and alantolactone was achieved by isocratic elution using water (containing 0.1% formic acid) and acetonitrile as the mobile phase using a ZORBAX Eclipse Plus C18 column. The total run time was 6.4 min. The present study showed poor absorption of isoalantolactone and alantolactone in vivo. The apparent Cmax, Tmax, T1/2 and total exposure (AUC0-12h) in rat plasma were 37.8 ng/mL, 120 min, 351.7 min and 6112.3 ng-min/mL for isoalantolactone and 25.9 ng/mL, 90 min, 321.0 min and 4918.9 ng-min/mL for alantolactone, respectively. It was shown that the highest concentration was achieved in the small intestine and feces clearance was shown to be the dominant elimination pathway of the lactones.

  9. INTESTINAL EXCRETION OF ENDOGENOUS ZINC IN GUATEMALAN SCHOOL CHILDREN

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: The intestine is the major route of excretion of endogenous zinc and has a key role in maintaining zinc homeostasis. Phytate has been reported to increase these losses. Objective: To determine the rate of excretion of endogenous zinc in school-aged children in a poor rural community for ...

  10. Biphasic changes in 3-methylhistidine excretion in humans after exercise.

    PubMed

    Dohm, G L; Israel, R G; Breedlove, R L; Williams, R T; Askew, E W

    1985-05-01

    We previously reported that 3-methylhistidine excretion was increased in human subjects after a strenuous bout of exercise. Because other investigators have not corroborated this finding, we undertook the present study to investigate the conditions that result in decreased and increased 3-methylhistidine excretion in human subjects after exercise. Four experiments were performed: a cross-sectional study comparing 3-methylhistidine excretion in endurance-trained subjects with untrained controls, a longitudinal study of 3-methylhistidine excretion by female basketball players before the start of the season and again during the competitive season, an experiment to determine changes in 3-methylhistidine excretion as a result of 2 h of exercise each day for 7 consecutive days, and a study to determine changes in 3-methylhistidine excretion during 4-h intervals after a strenuous exercise bout. The 3-methylhistidine-to-creatinine ratio was approximately 20% higher for trained than nontrained subjects. In three separate experiments a biphasic change of 3-methylhistidine excretion was observed in response to exercise with an immediate decrease in the 3-methylhistidine-to-creatinine ratio during exercise followed by a prolonged increase. The magnitudes of the negative and positive responses determine whether one observes an increase, no change, or a decrease in the total daily excretion of 3-methylhistidine.

  11. Urinary copper excretion and hepatic copper concentrations in liver disease.

    PubMed

    Frommer, D J

    1981-01-01

    Urinary copper excretion was found to be increased in patients with cholestasis, hepatitis and cirrhosis, but the penicillamine-induced increment was normal. Wilson's disease patients had increased copper excretion before and after penicillamine, especially in untreated cases. Hepatic copper concentrations correlated with urinary copper excretion in cholestasis and treated Wilson's disease, but not in hepatitis or cirrhosis. In treated Wilson's disease, measurement of urinary copper excretion should be valuable in estimating the degree of removal of copper from the body during therapy. Urinary copper clearances were raised in various liver conditions, maximally in untreated Wilson's disease. It is suggested that only part of the serum non-caeruloplasmin copper is available for excretion into urine.

  12. Excretion of biliary compounds during intrauterine life

    PubMed Central

    Macias, Rocio IR; Marin, Jose JG; Serrano, Maria A

    2009-01-01

    In adults, the hepatobiliary system, together with the kidney, constitute the main routes for the elimination of several endogenous and xenobiotic compounds into bile and urine, respectively. However, during intrauterine life the biliary route of excretion for cholephilic compounds, such as bile acids and biliary pigments, is very 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. PMID:19230042

  13. Excretion of drugs in human breast milk

    SciTech Connect

    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.

  14. An isotopic study of oxalate excretion in sheep.

    PubMed

    McIntosh, G H; Belling, G B

    1975-12-01

    Intravenously injected 14C labelled oxalate was rapidly removed from the blood stream via the kidney in 2 sheep, 75% being cleared within 8 h. Mean daily urinary oxalate excretions over 5 days were 21-2 and 27-5 mg and the derived plasma oxalate concentrations were 52-6 and 74-4 mug/100 ml, respectively. Oxalate was both filtered and secreted by the renal tubule with oxalate/inulin ratios varying from 1-11 to 1-57 in 6 normal sheep. A large increase in calcium excretion induced by calcium borogluconate infusion over 5 days was accompanied by a small but consistent increase in urinary oxalate excretion relative to calcium. Oxalate in blood was to be found mainly in the plasma, there being a small (8%) proporation within erythrocytes. This is lower than that reported for man, and yet in its excretion of oxalate via the kidney the sheep appears to closely resemble man and dog.

  15. Diet and urinary excretion of lignans in female subjects.

    PubMed

    Adlercreutz, H; Fotsis, T; Heikkinen, R; Dwyer, J T; Goldin, B R; Gorbach, S L; Lawson, A M; Setchell, K D

    1981-08-01

    Lignans, a class of compounds having a 2,3-dibenzylbutane skeleton, have recently been identified for the first time in humans and animals and evidence indicating their formation by intestinal microflora has previously been established in rats and humans. In the present report the influence of diet on the biosynthesis of this new group of compounds was investigated by comparing the urinary excretion of the principal lignan, trans-2,3-bis-(3-hydroxybenzyl) -butyrolactone (enterolactone, HBBL), in 12 omnivoric and 14 vegetarian women. Young vegetarian women were found to excrete significantly greater amounts of enterolactone than omnivores, while old vegetarians excreted comparable amounts to the omnivore group. A statistically significant (P less than 0.01-0.001) correlation was found between the amount of fibre in the diet and the urinary enterolactone excretion.

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

    PubMed

    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

  17. Plasma disposition and faecal excretion of oxfendazole, fenbendazole and albendazole following oral administration to donkeys.

    PubMed

    Gokbulut, Cengiz; Akar, Ferda; McKellar, Quintin A

    2006-07-01

    Fenbendazole (FBZ), oxfendazole (fenbendazole sulphoxide, FBZSO), and albendazole (ABZ) were administered orally to donkeys at 10mg/kg bodyweight. Blood and faecal samples were collected from 1 to 120 h post-treatment. The plasma and faecal samples were analysed by high performance liquid chromatography (HPLC). The parent molecule and its sulphoxide and sulphone (FBZSO(2)) metabolites did not reach detectable concentrations in any plasma samples following FBZ administration. ABZ was also not detected in any plasma samples, but its sulphoxide and sulphone metabolites were detected, demonstrating that ABZ was completely metabolised by first-pass mechanisms in donkeys. Maximum plasma concentrations (C(max)) of FBZSO (0.49microg/mL) and FBZSO(2) (0.60microg/mL) were detected at (t(max)) 5.67 and 8.00h, respectively, following administration of FBZSO. The area under the curve (AUC) of the sulphone metabolite (10.33microg h/mL) was significantly higher than that of the parent drug FBZSO (5.17microg h/mL). C(max) of albendazole sulphoxide (ABZSO) (0.08g/mL) and albendazole sulphone (ABZSO(2)) (0.04microg/mL) were obtained at 5.71 and 8.00h, respectively, following ABZ administration. The AUC of the sulphoxide metabolite (0.84microg h/mL) of ABZ was significantly higher than that of the sulphone metabolite (0.50microg h/mL). The highest dry-faecal concentrations of parent molecules were detected at 32, 34 and 30h for FBZSO, FBZ and ABZ, respectively. The sulphide metabolite was significantly higher than the parent molecule after FBZSO administration. The parent molecule was predominant in the faecal samples following FBZ administration. After ABZ administration, the parent molecule was significantly metabolised, probably by gastrointestinal microflora, to its sulphoxide metabolite (ABZSO) that showed a similar excretion profile to the parent molecule in the faecal samples. The AUC of the parent FBZ was significantly higher than that of FBZSO and ABZ in faeces. It is

  18. Species differences in biliary excretion of benzo(a)pyrene

    SciTech Connect

    Weyand, E.H.; Bevan, D.R.

    1986-05-01

    Biliary excretion of benzo(a)pyrene (B(a)P) was investigated in rats, hamsters, and guinea pigs following intratracheal administration. (/sup 3/H)-B(a)P, in amounts of approximately 150 ng or 350 ..mu..g, was instilled into lungs and amounts of radioactivity excreted in bile were monitored for six hrs following administration. Differences in biliary excretion of (/sup 3/H)-B(a)P and/or metabolites among species were observed at low doses but not at high doses. Six hours after instillation of a low dose of B(a)P, 70, 54, and 62% of the dose was excreted in bile of rats, hamsters, and guinea pigs, respectively. Upon administration of the higher dose of B(a)P, approximately 50% of the dose was excreted in bile in six hrs by all species. Thus, rats and guinea pigs exhibit differences in biliary excretion of low and high doses of B(a)P whereas hamsters do not. Profiles of phase II metabolites in rats and hamsters were similar at both low and high doses, with the majority of metabolites being glucuronides and thioether conjugates. However, differences in relative amounts of these conjugates were observed between the two doses, with a shift towards a greater proportion of glucuronides at the higher dose. Metabolites in bile from guinea pigs were primarily thioether conjugates, which accounted for 88% of metabolites at the low dose and 95% at the high dose.

  19. Kinetic analysis of biliary lipid excretion in man and dog.

    PubMed Central

    Wagner, C I; Trotman, B W; Soloway, R D

    1976-01-01

    To understand better the mechanisms involved in biliary lipid excretion and to evaluate their role in cholesterol gallstone formation, the rates of biliary excretion of bile salts, cholesterol, and phospholipids were measured in two species, man and dog. Seven cholecystectomized patients with balloon-occludable reinfusion T-tubes were studied during intact and interrupted enterohepatic circulation and four cholecystectomized dogs were studied during interrupted enterohepatic circulation. In man and dog both cholesterol and phospholipid outputs were hyperbolically related to bile salt output by the equation y = x/(a + bx). The output curves intersected the origin and showed an initial rapid rise, followed by a slower increase to a maximum, suggesting a rate-limited mechanism. The shape of the curves permitted calculation of the theoretical maximal outputs and the rates of rise to those outputs. Comparison of these values showed that in both man and dog phospholipid output was greater than cholesterol output and that cholesterol and phospholipid were excreted at different rates. These studies (a) indicate that cholesterol, phospholipids, and bile salts are not excreted in a fixed relationship and (b) demonstrate the usefulness of the derived theoretical maximal lipid output, and the rate of rise of lipid excretion to a maximum, in evaluating the kinetics of biliary lipid excretion. PMID:943421

  20. Ammonia excretion in the freshwater planarian Schmidtea mediterranea.

    PubMed

    Weihrauch, Dirk; Chan, Ainsely C; Meyer, Heiko; Döring, Carmen; Sourial, Mary; O'Donnell, Michael J

    2012-09-15

    In aquatic invertebrates, metabolic nitrogenous waste is excreted predominately as ammonia. Very little is known, however, of the underlying mechanisms of ammonia excretion, particularly in freshwater species. Our results indicate that in the non-parasitic freshwater planarian Schmidtea mediterranea, ammonia excretion depends on acidification of the apical unstirred layer of the body surface and consequent ammonia trapping. Buffering of the environment to a pH of 7 or higher decreased the excretion rate. Inhibitor experiments suggested further that the excretion mechanism involves the participation of the V-type H(+)-ATPase and carbonic anhydrase and possibly also the Na(+)/K(+)-ATPase and Na(+)/H(+) exchangers. Alkalinization (pH 8.5, 2 days) of the environment led to a 1.9-fold increase in body ammonia levels and to a downregulation of V-ATPase (subunit A) and Rh-protein mRNA. Further, a 2 day exposure to non-lethal ammonia concentrations (1 mmol l(-1)) caused a doubling of body ammonia levels and led to an increase in Rh-protein and Na(+)/K(+)-ATPase (α-subunit) mRNA expression levels. In situ hybridization studies indicated a strong mRNA expression of the Rh-protein in the epidermal epithelium. The ammonia excretion mechanism proposed for S. mediterranea reveals striking similarities to the current model suggested to function in the gills of freshwater fish.

  1. Coordinacy of lysosomal enzyme excretion in human urine.

    PubMed Central

    Paigen, K; Peterson, J

    1978-01-01

    Assay conditions have been developed for the determination of urinary beta-glucuronidase, beta-galactosidase, alpha-galactosidase, and beta-hexosaminidase using fluorometric substrates. The assay conditions for beta-glucuronidase overcome interference by both low and high molecular weight inhibitors, a problem that has confused earlier studies of enzyme excretion. The four lysosomal enzymes are excreted corrdinately: although their absolute levels (in units per milligram of creatinine) vary during the day and from one day to the next, the ratio of one enzyme to another remains relatively constant. The lack of correlation betweem plasma and urine enzyme levels, together with the high molecular weights of these enzymes, suggests that the urinary enzymes are not derived by glomerular filtration. The lack of coordinacy with lactate dehydrogenase suggests they are not derived from exfoliated cells. by analogy with experimental animals, they may be derived from lysosomes extruded into the lumen of the proximal tubule by epithelial cells. There is considerable variation among a population of 125 healthy adult subjects for total enzyme excretion. Both total enzyme excretion and coordinacy ratios are log-normally distributed, suggesting that they are the resultants of many factors, each of which has a relative, or proportional, effect on enzyme excretion. About one-half the population variation resides in a process common to the excretion of all four enzymes (possibly the lysosome extrusion pathway), and about one-half resides in factors affecting each enzyme independently. PMID:25285

  2. Urinary chromium excretion, diurnal changes, and relationship to creatinine excretion in healthy and sick individuals of different ages.

    PubMed

    Gürson, C T; Saner, G

    1978-07-01

    Since urine is the main excretory pathway for chromium, this study was conducted to compare in normal individuals the daily urinary chromium excretion with a 4 hr sample, to investigate diurnal fluctuations of urinary chromium and age-dependent relationship between urinary chromium and creatinine excretion. The results can be summarized as 1) there was no significant difference between the observed 24 hr chromium excretion and 24 hr excretion calculated from the one 4 hr samples, 2) a diurnal variation was observed when urinary excretion was expressed as chromium per minute, but no time-related variation could be established when chromium/creatinine (Cr/Cre) ratios in samples from three different periods of the same day were compared, although a significant positive correlation existed between urinary chromium and creatinine concentration, 3) the Cr/Cre ratio was found to be age-dependent, 4) in malnourished children the Cr/Cre ratio was very high and significantly different from that of normal infants, 5) This ratio for the eight diabetics was found to be significantly higher when compared with normal adults. On the basis of these results, it is suggested that morning 4 hr urinary chromium reflects the daily chromium excretion and that the Cr/Cre ratio of single urine samples obtained during this period is a reliable criterion in the evaluation of chromium nutrition of individuals in different conditions, provided that the influence of age is taken into consideration.

  3. [Trans-intestinal cholesterol excretion (TICE): a new route for cholesterol excretion].

    PubMed

    Blanchard, Claire; Moreau, François; Cariou, Bertrand; Le May, Cédric

    2014-10-01

    The small intestine plays a crucial role in dietary and biliary cholesterol absorption, as well as its lymphatic secretion as chylomicrons (lipoprotein exogenous way). Recently, a new metabolic pathway called TICE (trans-intestinal excretion of cholesterol) that plays a central role in cholesterol metabolism has emerged. TICE is an inducible way, complementary to the hepatobiliary pathway, allowing the elimination of the plasma cholesterol directly into the intestine lumen through the enterocytes. This pathway is poorly characterized but several molecular actors of TICE have been recently identified. Although it is a matter of debate, two independent studies suggest that TICE is involved in the anti-atherogenic reverse cholesterol transport pathway. Thus, TICE is an innovative drug target to reduce -cardiovascular diseases.

  4. Quantitative urinary protein excretion in chronic renal failure.

    PubMed

    McMorrow, R G; Galla, J H; Luke, R G

    1982-01-01

    The diagnostic value of the measurement of quantitative proteinuria in patients with a creatinine clearance of less than 10 ml/min was determined in patients seen in a single center over a 5-year period. All 126 patients in whom a definitive renal diagnosis was possible were included. Patients with glomerular disease excreted 6.1 +/- 0.6 g/day and patients with interstitial disease 1.5 +/- 0.3 g/day (p less than 0.001). In individual patients with end-stage renal disease, however, measurement of urinary protein excretion excluded (with 95% confidence levels) patients with interstitial diseases only when greater than 2.9 g/day. To examine the natural history of proteinuria in progressive renal disease, urinary protein, absolute and factored for glomerular filtration rate (GFR; creatinine clearance), was determined at 10 ml/min decrements in GFR for patients with membranoproliferative glomerulonephritis, idiopathic membranous glomerulonephritis and focal glomerulosclerosis. Quantitative urinary protein excretion was relatively constant as GFR fell but did fall significantly at less than 10 ml/min but only to 4.8-7.0 g/day at even that level. Urinary protein excretion/GFR increased as GFR fell, particularly at end stage where a highly significant four-fold rise was seen; an increase also occurred in patients with primary interstitial disease. Similar data were obtained for 34 randomly selected patients after at least 1 year of chronic hemodialysis. Although a significant decline in absolute urinary protein excretion occurred during the year of dialysis to levels not different between glomerular and interstitial disease, urinary protein excretion/unit GFR remained elevated. Increased urinary protein excretion/unit GFR may result from a functional adaptation of remaining nephrons in response to declining renal mass.

  5. Urinary Sodium and Potassium Excretion and CKD Progression.

    PubMed

    He, Jiang; Mills, Katherine T; Appel, Lawrence J; Yang, Wei; Chen, Jing; Lee, Belinda T; Rosas, Sylvia E; Porter, Anna; Makos, Gail; Weir, Matthew R; Hamm, L Lee; Kusek, John W

    2016-04-01

    CKD is a major risk factor for ESRD, cardiovascular disease, and premature death. Whether dietary sodium and potassium intake affect CKD progression remains unclear. We prospectively studied the association of urinary sodium and potassium excretion with CKD progression and all-cause mortality among 3939 patients with CKD in the Chronic Renal Insufficiency Cohort Study. Urinary sodium and potassium excretion were measured using three 24-hour urine specimens, and CKD progression was defined as incident ESRD or halving of eGFR. During follow-up, 939 CKD progression events and 540 deaths occurred. Compared with the lowest quartile of urinary sodium excretion (<116.8 mmol/24 h), hazard ratios (95% confidence intervals) for the highest quartile of urinary sodium excretion (≥194.6 mmol/24 h) were 1.54 (1.23 to 1.92) for CKD progression, 1.45 (1.08 to 1.95) for all-cause mortality, and 1.43 (1.18 to 1.73) for the composite outcome of CKD progression and all-cause mortality after adjusting for multiple covariates, including baseline eGFR. Additionally, compared with the lowest quartile of urinary potassium excretion (<39.4 mmol/24 h), hazard ratios for the highest quartile of urinary potassium excretion (≥67.1 mmol/24 h) were 1.59 (1.25 to 2.03) for CKD progression, 0.98 (0.71 to 1.35) for all-cause mortality, and 1.42 (1.15 to 1.74) for the composite outcome. These data indicate that high urinary sodium and potassium excretion are associated with increased risk of CKD progression. Clinical trials are warranted to test the effect of sodium and potassium reduction on CKD progression.

  6. Homeostatic control of manganese excretion in the neonatal rat

    SciTech Connect

    Ballatori, N.; Miles, E.; Clarkson, T.W.

    1987-05-01

    Previous studies in neonatal and suckling animals showed that immature animals have a greatly diminished capacity to excrete manganese and therefore were considered to be unable to regulate tissue manganese concentrations. In contrast, the present studies indicate that suckling rats have the capacity to excrete excess manganese at rates nearly comparable to those of adults. Eight- to 10-day-old rats given a tracer dose of /sup 54/MnCl/sub 2/ (essentially carrier free), either via gavage or by intraperitoneal injection showed little elimination of the /sup 54/Mn until the 18-19th day of life, when there was an abrupt increase in the rate of the metal's excretion. However, when manganese was given in doses of 1 and 10 mg/kg, the young animals excreted from 30-70% of the dose in only 4 days, at which time a new rate of excretion was achieved. This enhanced rate of excretion remained constant until the 18-19th day of life, when it was again accelerated. Biliary excretion of manganese, the primary route for the elimination of the metal, was only 30-60% lower in 14-day-old rats compared with adults at doses ranging from tracer to 10 mg /sup 54/Mn/kg. For both the 14-day-old and adult rats, an apparent biliary transport maximum was reached at a dose of 10 mg Mn/kg. These studies indicate that the excretory pathways for manganese are well developed in the neonatal rat. The avid retention of tracer quantities of manganese by the neonate may be a consequence of the scarcity of this essential trace metal in its diet.

  7. Manure nutrient excretion by Jersey and Holstein cows.

    PubMed

    Knowlton, K F; Wilkerson, V A; Casper, D P; Mertens, D R

    2010-01-01

    The objective of this study was to evaluate feces, urine, and N excretion by Jersey and Holstein cows. Sixteen multiparous cows (n=8 per breed) were fed 2 experimental rations at calving in a switchback experimental design. Diets were 50% forage and based on corn meal (control) or whole cottonseed. Half the cows in each breed started on the control diet and half started on the whole cottonseed diet. Cows were switched to the other diet at 60 d in milk and switched back to their original diet at 165 d in milk. Pairs of cows were moved into open-circuit respiration chambers on d 49, 154, and 271 of lactation for 7-d measurement periods. While in the chambers, total collection of feed refusals, milk, recovered hair, feces, and urine was conducted. No effect of the interaction of diet and breed was observed for measures of nutrient digestibility and manure excretion. Total daily manure excretion was lower in Jersey cows than in Holstein cows, with reductions generally proportional to changes in feed intake. Jersey cows consumed 29% less feed and excreted 33% less wet feces and 28% less urine than Holstein cows. Intake, fecal, and urinary N were reduced by 29, 33, and 24%, respectively, in Jersey cows compared with Holstein cows. Equations from American Society of Agricultural and Biological Engineers underpredicted observed values for all manure measures evaluated (urine, manure solids, N, wet manure), and breed bias was observed in equations predicting excretion of urine, N, and wet manure. Although these equations include animal and dietary factors, intercepts of regression of observed values on predicted values differed between Holsteins and Jerseys for those 3 measures. No breed bias was observed in the prediction of manure solids excretion, however, making that equation equally appropriate for Jerseys and Holsteins. The effect of breed on manure and nutrient excretion has significant nutrient management implications.

  8. Biliary excretion of lecithin and cholesterol in the dog

    PubMed Central

    Wheeler, Henry O.; King, Katherine K.

    1972-01-01

    The biliary excretion rates of bile acid, lecithin, and cholesterol were measured in unanesthetized dogs after interruption of enterohepatic circulation and during infusions of sodium taurocholate, sodium glycocholate, sodium dehydrocholate, SC2644 (a bicyclic organic acid with high choleretic potency), and secretin. Both lecithin output and cholesterol output were directly related to bile acid excretion rate. The curves describing these relationships were concave downward. Molar concentration ratios of lecithin-to-bile acid declined gradually from approximately 0.4 to 0.2 as bile acid output increased from approximately 1 to 70 μmoles/min. Cholesterol-to-lecithin molar ratios were highest (0.05-0.15) at very low rates of bile acid excretion, but descended rapidly to a plateau (0.03-0.04) which was constant over the entire range of bile acid excretion rates from 10 to 70 μmoles/min. Similar lipid excretion patterns were observed during glycocholate infusion, but secretin-induced choleresis and dehydrocholate-induced choleresis were unaccompanied by any increments in lecithin or cholesterol excretion and SC2644 (which caused a marked increase in canalicular bile production as measured by erythritol clearance) caused a depression of lipid excretion. The data are consistent with the view that lecithin moves passively from cell membranes to intracanalicular micelles, that transport of cholesterol is coupled to lecithin transport, and that there is also a small amount of independent passive transport of cholesterol from membranes to micelles. A model developed on these assumptions has been shown to behave in a fashion consistent with the entire range of these observations. PMID:5024035

  9. Contribution of dietary oxalate to urinary oxalate excretion

    NASA Technical Reports Server (NTRS)

    Holmes, R. P.; Goodman, H. O.; Assimos, D. G.

    2001-01-01

    BACKGROUND: The amount of oxalate excreted in urine has a significant impact on calcium oxalate supersaturation and stone formation. Dietary oxalate is believed to make only a minor (10 to 20%) contribution to the amount of oxalate excreted in urine, but the validity of the experimental observations that support this conclusion can be questioned. An understanding of the actual contribution of dietary oxalate to urinary oxalate excretion is important, as it is potentially modifiable. METHODS: We varied the amount of dietary oxalate consumed by a group of adult individuals using formula diets and controlled, solid-food diets with a known oxalate content, determined by a recently developed analytical procedure. Controlled solid-food diets were consumed containing 10, 50, and 250 mg of oxalate/2500 kcal, as well as formula diets containing 0 and 180 mg oxalate/2500 kcal. Changes in the content of oxalate and other ions were assessed in 24-hour urine collections. RESULTS: Urinary oxalate excretion increased as dietary oxalate intake increased. With oxalate-containing diets, the mean contribution of dietary oxalate to urinary oxalate excretion ranged from 24.4 +/- 15.5% on the 10 mg/2500 kcal/day diet to 41.5 +/- 9.1% on the 250 mg/2500 kcal/day diet, much higher than previously estimated. When the calcium content of a diet containing 250 mg of oxalate was reduced from 1002 mg to 391 mg, urinary oxalate excretion increased by a mean of 28.2 +/- 4.8%, and the mean dietary contribution increased to 52.6 +/- 8.6%. CONCLUSIONS: These results suggest that dietary oxalate makes a much greater contribution to urinary oxalate excretion than previously recognized, that dietary calcium influences the bioavailability of ingested oxalate, and that the absorption of dietary oxalate may be an important factor in calcium oxalate stone formation.

  10. Isotopic Labeling of Red Cabbage Anthocyanins with Atmospheric 13-CO2

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Isotopic labeling of plants provides a unique opportunity for understanding metabolic processes. A significant challenge of isotopic labeling during plant growth is that isotopes must be administered without disrupting plant development and at sufficient levels for mass spectral analysis. We describ...

  11. Time-resolved metabolomics of a novel trebouxiophycean alga using (13)CO2 feeding.

    PubMed

    Ito, Takuro; Sugimoto, Masahiro; Toya, Yoshihiro; Ano, Yoshitaka; Kurano, Norihide; Soga, Tomoyoshi; Tomita, Masaru

    2013-09-01

    Oil-rich algae are potentially promising as next-generation biofuel feedstock. However, the productivity of oil needs to be improved for industrial use. The biosynthesis of oil and its control mechanism have not been characterized in any algae, and understanding the metabolic network is vital to achieve the precise engineering of algae metabolic pathways. "Pseudochoricystis ellipsoidea" MBIC 11204, a novel microalgal strain, accumulates a large amount of lipids in nitrogen-deficient conditions. In this study, "P. ellipsoidea" was grown in flat flasks with continuous illumination and aeration with 1% CO2 at 25°C. During the exponential growth phase, CO2 was switched to (13)C-labeled CO2 and samples were collected for time-course experiments. Seventy-eight pairs of unlabeled and uniformly (13)C-labeled metabolites were quantified using a capillary electrophoresis- and liquid chromatography-mass spectrometry for ionic primary metabolites and lipids, respectively. The (13)C-exchange indices of the metabolites were calculated from a concentration of unlabeled and uniformly-labeled metabolites. A hierarchical clustering analysis of the dynamics of the indices revealed 4 characteristic clusters, two of which represented rapidly-labeled metabolites, mainly composed of primary metabolites, while the two other clusters represented slowly-labeled metabolites, mainly composed of lipids. Moreover, the labeling order of these clusters was mainly matched to the metabolic process of Chlamydomonas reinhardtii, a model organism of green algae. In TCA cycle, anomalistically different of the labeling order was found. To the author's knowledge, this study for the first time in literature, characterize the features of global metabolism in "P. ellipsoidea." PMID:23706992

  12. Short communication: Evaluation of nitrogen excretion equations from cattle.

    PubMed

    Johnson, A C B; Reed, K F; Kebreab, E

    2016-09-01

    Nitrogen excretion in dairy manure is a precursor for N2O and NH3 formation in livestock housing, manure storage facilities, and after manure is applied to land. Nitrous oxide is a major contributor to greenhouse gas emissions, and reducing N output from dairy production facilities can reduce the amount of anthropogenic N2O entering the atmosphere. The objective of the study was to conduct a comprehensive evaluation of extant prediction models for N excretion in feces and urine using extensive literature data. A total of 45 N excretion equations were evaluated for lactating cows, heifers, and nonlactating cows and steers. These equations were evaluated with 215 treatment means from 69 published studies collected over 20 yr from 1995 to 2015. Two evaluation methods were used: the root mean square prediction error and the concordance correlation coefficient. Equations constructed using a more rigorous development process fared better than older extant equations. Equations for heifers and nonlactating cows had greater error of prediction compared with equations used for lactating cows. This could be due to limited amount of data available for construction and evaluation of the equations. Urinary N equations had greater prediction errors than other forms of excretion, possibly due to high variability in urinary N excretion and challenges in urine collection. Fecal N equations had low error bias and reached an acceptable level of precision and accuracy. PMID:27320670

  13. Renal melatonin excretion in sheep is enhanced by water diuresis.

    PubMed

    Valtonen, M; Laitinen, J T; Eriksson, L

    1993-09-01

    Diurnal variation in blood melatonin levels and renal melatonin excretion was monitored in five ewes by blood sampling and quantitative urine collection at 2-h intervals. A typical secretory pattern of melatonin was seen both in blood and urine levels and in the renal excretion of melatonin. Serum melatonin levels increased from daytime values of approximately 200 pmol/l to a mean of 800 pmol/l during darkness. Urine flow rate and urine osmolality did not show any clear diurnal rhythm. To examine whether urine flow rate affects renal melatonin excretion at night, urine was collected in three consecutive 30-min fractions, and blood was sampled in the middle of each urine collection period when the sheep were in normal water balance or after hydration. Hydration increased urine flow rate over sixfold and decreased urine osmolality well below plasma osmolality. Glomerular filtration rate, measured as creatinine clearance, did not change. Serum melatonin concentrations did not differ between hydrated and non-hydrated sheep. However, urinary melatonin excretion was 1.1 +/- 0.3 (S.E.M.) pmol/min at midnight in normal water balance, and significantly higher (2.6 +/- 0.4 pmol/min) in the hydrated state. In this study, the validity of urinary melatonin determinations as an indicator of pineal function was confirmed in normal water balance. In addition, our results suggest that a high tubular fluid load during diuresis increases urinary melatonin excretion because of decreased tubular reabsorption.(ABSTRACT TRUNCATED AT 250 WORDS)

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

    PubMed

    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.

  15. Urine excretion strategy for stem cell-generated embryonic kidneys

    PubMed Central

    Yokote, Shinya; Matsunari, Hitomi; Iwai, Satomi; Yamanaka, Shuichiro; Uchikura, Ayuko; Fujimoto, Eisuke; Matsumoto, Kei; Nagashima, Hiroshi; Kobayashi, Eiji; Yokoo, Takashi

    2015-01-01

    There have been several recent attempts to generate, de novo, a functional whole kidney from stem cells using the organogenic niche or blastocyst complementation methods. However, none of these attempts succeeded in constructing a urinary excretion pathway for the stem cell-generated embryonic kidney. First, we transplanted metanephroi from cloned pig fetuses into gilts; the metanephroi grew to about 3 cm and produced urine, although hydronephrosis eventually was observed because of the lack of an excretion pathway. Second, we demonstrated the construction of urine excretion pathways in rats. Rat metanephroi or metanephroi with bladders (developed from cloacas) were transplanted into host rats. Histopathologic analysis showed that tubular lumina dilation and interstitial fibrosis were reduced in kidneys developed from cloacal transplants compared with metanephroi transplantation. Then we connected the host animal’s ureter to the cloacal-developed bladder, a technique we called the “stepwise peristaltic ureter” (SWPU) system. The application of the SWPU system avoided hydronephrosis and permitted the cloacas to differentiate well, with cloacal urine being excreted persistently through the recipient ureter. Finally, we demonstrated a viable preclinical application of the SWPU system in cloned pigs. The SWPU system also inhibited hydronephrosis in the pig study. To our knowledge, this is the first report showing that the SWPU system may resolve two important problems in the generation of kidneys from stem cells: construction of a urine excretion pathway and continued growth of the newly generated kidney. PMID:26392557

  16. Ultra-performance liquid-chromatography with tandem mass spectrometry for rapid analysis of pharmacokinetics, biodistribution and excretion of schisandrin after oral administration of Shengmaisan.

    PubMed

    Lu, Sheng-Wen; Zhang, Ai-Hua; Sun, Hui; Yan, Guang-Li; Han, Ying; Wu, Xiu-Hong; Wang, Xi-Jun

    2013-12-01

    This study aimed to investigate the in vivo behaviors of the main components in traditional Chinese medicine (TCM) fomulae. The plasma pharmacokinetics, tissue distribution and excretion of the main component-schisandrin in rats after oral administration of a classical TCM prescription, shengmaisan (SMS), were studied by a developed and validated UPLC-MS/MS method. The separation of schisandrin was achieved on a UPLC HSS T3 column with a mobile phase consisting of acetonitrile and water at a flow rate of 0.5 mL/min by linear gradient elution. The MS/MS detection was carried out by monitoring the fragmentation of m/z 415.22 → 384.26 for schisandrin on a triple quadrupole mass spectrometer. The result showed that the method was suitable for the quantification of schisandrin in plasma, tissue and excreta samples with satisfactory selectivity, precision, accuracy, sensitivity, linearity and recovery. Pharmacokinetic results showed a rapid absorption phase with the mean Tmax of 0.17 h and a relatively slow elimination proceeding with a half-life (T1/2 ) of 5.24 ± 1.28 h. The tissue distribution showed the maximum concentration distributions of schisandrin after oral administration of SMS were in the order of small intestine > large intestine > lung > liver > kidney > spleen > heart > brain. Only 0.005-0.006% of schisandrin was recovered in feces and was not detected in urine.

  17. Internal dosimetry of plutonium using the late urinary excretion.

    PubMed

    Sharma, R C; Abani, M C

    2000-10-01

    An attempt has been made to standardize the methodology of internal dose computation from the late urinary excretion data. The methodology was selected keeping in mind the most recent ICRP publications and the results of internal dosimetry intercomparison studies reported in literature. The key element of this methodology is the PC-based computational software LUDEP 2.05, which implements the new model of the human respiratory tract. Late urinary excretion data of three male subjects involved in accidental intakes of plutonium aerosols more than 25 years ago were interpreted in terms of intakes and internal doses with the aid of the standardized methodology. An important implication of this work is that late urinary excretion data of the occupational workers of any plutonium handling facility could be used to show the compliance with the life-time dose limit.

  18. Urinary excretion of methaqualone-N-oxide in man.

    PubMed

    Reynolds, C N; Wilson, K; Burnett, D

    1976-02-01

    1. Oral administration of therapeutic doses (250 mg) of methaqualone (Melsed) to adult human subjects gives rise to the urinary excretion of methaqualone-N-oxide. This metabolite has been identified by chromatography and mass spectrometry and quantitatively determined by reduction with titanium trichloride to methaqualone which was then determined by g.l.c. 2. The N-oxide accounts for 5-9% of the dose in 24 h. 3. 2-Nitrobenzo-o-toluidide, a possible oxidation product of methaqualone-N-oxide, has not been detected. 4. The urinary excretion of unchanged methaqualone is less than 0-3% of the dose. The ease with which methaqualone-N-oxide is thermally converted to methaqualone casts doubts on the previously published figures for the urinary excretion of methaqualone.

  19. Urinary excretion pattern of methaqualone metabolites in man.

    PubMed

    Ericsson, O; Danielsson, B

    1977-01-01

    A method based on selected ion monitoring for determination of five monohydroxy metabolites of methaqualone in urine has been worked out. By means of this method the time course of metabolite excretion was studied in three healthy volunteers receiving an oral therapeutic dose of methaqualone. In all subjects the main monohydroxy metabolite was conjugated 4'-hydroxymethaqualone, but the relative importance of the five metabolites showed intersubject variation. Metabolite excretion was still going on, when urine sampling was discontinued after 70 hr. Only small amounts (less than 1% of the dose during 70 hr) of unmetabolized methaqualone were excreted. On the other hand, it was confirmed that methaqualone-N1-oxide is an important metabolite. The presence of a hydroxy methoxy metabolite of methaqualone, very probably 4'-hydroxy-5'-methoxymethaqualone, as a minor metabolite was established by comparison with authentic, synthetic material. 8-Hydroxymethaqualone and 2-nitrobenz-o-toluidide, reported by other groups, could not be detected.

  20. Quantitation of phosphorus excretion in sheep by compartmental analysis

    SciTech Connect

    Schneider, K.M.; Boston, R.C.; Leaver, D.D.

    1987-04-01

    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 /sup 32/P 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.

  1. Dynamics of renal electrolyte excretion in growing mice.

    PubMed

    Schmidt, Katharina; Ripper, Maria; Tegtmeier, Ines; Humberg, Evelyn; Sterner, Christina; Reichold, Markus; Warth, Richard; Bandulik, Sascha

    2013-01-01

    Genetically modified mice represent important models for elucidating renal pathophysiology, but gene deletions frequently cause severe failure to thrive. In such cases, the analysis of the phenotype is often limited to the first weeks of life when renal excretory function undergoes dramatic physiological changes. Here, we investigated the postnatal dynamics of urinary ion excretion in mice. The profiles of urinary electrolyte excretion of mice were examined from birth until after weaning using an automated ion chromatography system. Postnatally, mice grew about 0.4 g/day, except during two phases with slower weight gain: (i) directly after birth during adaptation to extrauterine conditions (P0-P2) and (ii) during the weaning period (P15-P21), when nutrition changed from mother's milk to solid chow and water. During the first 3 days after birth, remarkable changes in urinary Na(+), Ca(2+), Mg(2+), and phosphate concentrations occurred, whereas K(+) and Cl(-) concentrations hardly changed. From days 4-14 after birth, Na(+), Ca(2+), Mg(2+), K(+), and Cl(-) concentrations remained relatively stable at low levels. Urinary concentrations of creatinine, NH4(+), phosphate, and sulfate constantly increased from birth until after weaning. Profiles of salt excretion in KCNJ10(-/-) mice exemplified the relevance of age-dependent analysis of urinary excretion. In conclusion, the most critical phases for analysis of renal ion excretion during the first weeks of life are directly after birth and during the weaning period. The age dependence of urinary excretion varies for the different ions. This should be taken into consideration when the renal phenotype of mice is investigated during the first weeks of life. PMID:24296675

  2. Aztreonam biliary excretion in bile duct ligated jaundiced rats.

    PubMed

    Rulli, F; Muzi, M; Zanella, E; Cipriani, P; Magni, A; Giordano, A; Filadoro, F

    1991-04-01

    An experimental study was undertaken to assess aztreonam biliary concentrations in bile duct ligated jaundiced rats. The study proved that aztreonam biliary concentrations are sufficient to inhibit Gram-negative bacteria within the first and the second hour after antibiotic administration. The experimental model suggests that clinical conditions such as lithiasis or neoplasms of the biliary tree should not totally inhibit the antibiotic excretion.

  3. Predicting nitrogen excretion in commercial grazing system dairy farms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Improving nitrogen (N) management on dairy farms is best facilitated through management of dairy cow feed N intakes (NI), due to strong associations between NI, feed N use efficiencies (NUE, proportion of NI secreted as milk N) and manure N excretion (Nex). Milk urea N (MUN) has also been used as an...

  4. Excretion of intracorporeal cadmium with S-benzoylthiamin monophosphate

    SciTech Connect

    Yamamoto, J.; Kaneda, Y.

    1995-05-01

    Examination was made of the excretion of intracorporeal methylmercury into body hair by the administration of thiamin tetrahydrofurfuryl disulfide (TTFD) which caused significant increase in mercury content in human mustache. The thiamin derivative, S-benzoylthiamin monophosphate (BTMP) failed to have such effect. The mechanism of mercury excretion is thus based on the side chain structure of TTFD, mercaptan. At the start of the 20th century in Japan, many multiparae were found to have itai-itai disease, the main symptom of which is general pain. The cause of this disease was considered cadmium deposition on the bone from sourced such as soil and river water which contaminated rice and cereals. The previous system for mercury was applied based on cadmium content variation in human mustache. Although TTFD worked well in the mercury excretion system, the usual dosage of TTFD administered orally did not cause significant increase in cadmium in the mustache. BTMP appeared to exert effect by generating thiol-type thiamin. Experiments in vitro should be conducted to demonstrate the chelating effects of thiol-type thiamin. It is quite important to find evidence for cadmium excretion from human body. 3 refs., 2 figs., 2 tabs.

  5. INFLUENCE OF DIETARY ARSENIC ON URINARY ARSENIC METABOLITE EXCRETION

    EPA Science Inventory

    Influence of Dietary Arsenic on Urinary Arsenic Metabolite Excretion

    Cara L. Carty, M.S., Edward E. Hudgens, B.Sc., Rebecca L. Calderon, Ph.D., M.S.P.H., Richard Kwok, M.S.P.H., Epidemiology and Biomarkers Branch/HSD, NHEERL/US EPA; David J. Thomas, Ph.D., Pharmacokinetics...

  6. Renal Regulation of Acid-Base Balance: Ammonia Excretion.

    ERIC Educational Resources Information Center

    Tanner, George A.

    1984-01-01

    Describes an experiment which demonstrates changes in ammonia excretion and urine pH that occur in response to metabolic acidosis (induced by ammonium chloride ingestion) or metabolic alkalosis (produced by sodium bicarbonate ingestion). List of materials needed and background information are included. Typical results are provided and discussed.…

  7. Urinary Calcium Excretion After Immobilization and Spinal Fusion in Adolescents

    PubMed Central

    Millard, F. J. C.; Nassim, J. R.; Woollen, J. W.

    1970-01-01

    The effect of prolonged immobilization and spinal fusion on the urinary calcium excretion of adolescents is described. Some patients developed severe hypercalcuria, but there was considerable individual variation. No significant difference was found between the sexes nor between patients with scoliosis due to muscle weakness and idiopathic scoliosis. PMID:5427856

  8. Increased leukotriene E4 excretion in systemic mastocytosis.

    PubMed

    Butterfield, Joseph H

    2010-06-01

    Cysteinyl leukotrienes such as LTE(4) are produced by mast cells, neutrophils, eosinophils, and macrophages. LTE(4) levels have not been reported in systemic mastocytosis, a disorder with a large increase in mast cell numbers. Urinary LTE(4) from patients referred for symptoms potentially due to mast cell degranulation or systemic mastocytosis was measured by a commercial cysteinyl leukotriene enzyme immunoassay kit. The diagnosis of systemic mastocytosis was established using current World Health Organization criteria. Compared with a control group of patients with various potential mast cell-related symptoms (e.g., "spells"), patients with systemic mastocytosis had a significant (P=.01) increase in urinary LTE(4) excretion, whether expressed as LTE(4) ng/g creatinine or as LTE(4) ng/24h. There was a moderate correlation of LTE(4) ng/24h with excretion of N-methyl histamine and serum tryptase but not with urinary 11beta-prostaglandin F(2alpha) (11beta-PGF(2alpha)) excretion. LTE(4) excretion is increased in patients with systemic mastocytosis and potentially contributes to clinical symptoms.

  9. Urinary Albumin Excretion and Vascular Function in Rheumatoid Arthritis.

    PubMed

    Pieringer, Herwig; Brummaier, Tobias; Piringer, Bettina; Auer-Hackenberg, Lorenz; Hartl, Andreas; Puchner, Rudolf; Pohanka, Erich; Schmid, Michael

    2016-03-01

    Rheumatoid arthritis (RA) is associated with significant cardiovascular (CV) morbidity and mortality. Increased urinary albumin excretion is a marker of CV risk. There are only few data on urinary albumin excretion in RA patients. Aim of the present study was to investigate urinary albumin excretion in RA patients and analyze, whether there is an association between urinary albumin excretion and vascular function as measured by the augmentation index (AIx). In a total of 341 participants (215 with RA, 126 without RA) urinary albumin-creatinine ratio (ACR) was determined and the AIx was measured. The Kolmogorov-Smirnov-test was used to cluster patient groups whose distributions of ACR can be considered to be equal. A crude analysis showed a median ACR of 6.6 mg/g in the RA group and 5.7 mg/g in patients without RA (P > 0.05). In order to account for diabetes (DM) we formed 4 distinct patient groups. Group 1: RA-/DM- (n = 74); group 2: RA+/DM- (n = 195); group 3: RA-/DM+ (n = 52); group 4: RA+/DM+ (n = 20). Clustering of these groups revealed two distinct patient groups: those without RA and DM, and those with either RA or DM or both. The latter group showed statistically significant higher ACR (median 8.1 mg/g) as the former (median 4.5 mg/g). We found no significant correlation between AIx and ACR. Urinary albumin excretion in patients with RA or DM or both is higher than in subjects without RA and DM. This can be seen as a sign of vascular alteration and increased CV risk in these patients. PMID:26955238

  10. Effect of diethyl ether on the biliary excretion of acetaminophen.

    PubMed

    Watkins, J B; Siegers, C P; Klaassen, C D

    1984-10-01

    The biliary and renal excretion of acetaminophen and its metabolites over 8 hr was determined in rats exposed to diethyl ether by inhalation for 1 hr. Additional rats were anesthetized with urethane (1 g/kg ip) while control animals were conscious throughout the experiment (surgery was performed under hexobarbital narcosis: 150 mg/kg ip; 30-min duration). The concentration of UDP-glucuronic acid was decreased 80% in livers from ether-anesthetized rats but was not reduced in urethane-treated animals when compared to that in control rats. The concentration of reduced glutathione was not affected by either urethane or diethyl ether. Basal bile flow was not altered by the anesthetic agents. Bile flow rate after acetaminophen injection (100 mg/kg iv) was increased slightly over basal levels for 2 hr in hexobarbital-treated control rats, was unaltered in urethane-anesthetized animals, and was decreased throughout the 8-hr experiment in rats exposed to diethyl ether for 1 hr. In control and urethane-anesthetized animals, approximately 30-35% of the total acetaminophen dose (100 mg/kg iv) was excreted into bile in 8 hr, while only 16% was excreted in rats anesthetized with diethyl ether. Urinary elimination (60-70% of the dose) was not altered by exposure to ether. Separation of metabolites by reverse-phase high-pressure liquid chromatography showed that ether decreased the biliary elimination of unchanged acetaminophen and its glucuronide, sulfate, and glutathione conjugates by 47, 40, 49, and 73%, respectively, as compared to control rats. Excretion of unchanged acetaminophen and the glutathione conjugate into bile was depressed in urethane-anesthetized animals by 45 and 66%, respectively, whereas elimination of the glucuronide and sulfate conjugates was increased by 27 and 50%, respectively. These results indicate that biliary excretion is influenced by the anesthetic agent and that diethyl ether depresses conjugation with sulfate and glutathione as well as glucuronic

  11. Racial differences in microalbumin excretion in healthy adolescents.

    PubMed

    Hanevold, Coral D; Pollock, Jennifer S; Harshfield, Gregory A

    2008-02-01

    It has been suggested that "normal" levels of urine albumin excretion rate (AER) may be predictive of an increased risk for progression of hypertension, cardiovascular morbidity, and mortality. No data are available on the effect of race and gender on AER in normal youth. We evaluated AER in timed urine samples in subjects participating in a study of stress-induced pressure natriuresis. A total of 317 healthy, normotensive adolescents aged 15 to 18 years (155 males and 162 females; 216 blacks and 101 whites) participated in a 5-hour testing protocol, which included a 1-hour period of mental stress preceded and followed by a 2-hour rest period. AER (micrograms per minute) was determined after 60 minutes of rest, and log transformation was used to normalize the data. AER was significantly higher in blacks as compared with whites (P=0.006). We also found a race-by-sex interaction, which was driven by the low albumin excretion in white females (P=0.036). Indexing urine albumin to creatinine excretion revealed the same pattern. Among blacks, AER was also higher in subjects who demonstrated impaired stress-induced pressure natriuresis versus those with normal sodium excretion (P=0.024). AER was related to blood pressure only in African-American males. The relative elevation of AER in normotensive black adolescents and the association with impaired pressure natriuresis and blood pressure is noteworthy. These findings suggest that albumin excretion may be a marker for a population at increased risk for the development of vascular and renal injury even before the manifestation of hypertension. PMID:18172060

  12. Elevated urinary excretion of aluminium and iron in multiple sclerosis.

    PubMed

    Exley, Christopher; Mamutse, Godwin; Korchazhkina, Olga; Pye, Eleanor; Strekopytov, Stanislav; Polwart, Anthony; Hawkins, Clive

    2006-10-01

    Multiple sclerosis (MS) is a chronic, immune-mediated, demyelinating disease of the central nervous system of as yet unknown aetiology. A consensus of opinion has suggested that the disorder is the result of an interplay between environmental factors and susceptibility genes. We have used a battery of analytical techniques to determine if the urinary excretion of i) markers of oxidative damage; ii) iron and iii) the environmental toxin aluminium and its antagonist, silicon, are altered in relapsing-remitting (RRMS) and secondary progressive MS (SPMS). Urinary concentrations of oxidative biomarkers, MDA and TBARS, were not found to be useful indicators of inflammatory disease in MS. However, urinary concentrations of another potential marker for inflammation and oxidative stress, iron, were significantly increased in SPMS (P<0.01) and insignificantly increased in RRMS (P>0.05). Urinary concentrations of aluminium were also significantly increased in RRMS (P<0.001) and SPMS (P <0.05) such that the levels of aluminium excretion in the former were similar to those observed in individuals undergoing metal chelation therapy. The excretion of silicon was lower in MS and significantly so in SPMS (P<0.05). Increased excretion of iron in urine supported a role for iron dysmetabolism in MS. Levels of urinary aluminium excretion similar to those seen in aluminium intoxication suggested that aluminium may be a hitherto unrecognized environmental factor associated with the aetiology of MS. If aluminium is involved in MS then an increased dietary intake of its natural antagonist, silicon, might be a therapeutic option.

  13. Increased Renal Solute Excretion in Rats Following Space Flight

    NASA Technical Reports Server (NTRS)

    Wade, Charles E.; Moore, A. L.; Morey-Holton, E.

    1995-01-01

    Following space flight a diuresis, due to an increase in free water clearance, has been suggested in humans. To assess the effects of space flight on renal function, rats were flown in space for 14 days. Rats were divided into three groups; vivarium controls (V;n=6; housed 2/shoe box cage), flight controls (FC;n=6; group housed in a flight cage), and flight animals (F;n=6). Upon landing all animals were placed into individual metabolic cages. Urine was collected daily for 7 days and every other day for 14 days. Urine output was increased (p less than 0.05; ANOVA) following flight for 3 days. On postflight day 1, flow rates were, V=6.8 plus or minus 0.9, FC=8.711.8 and F=16.6 plus or minus 2.7 microliter/min. Excretion rates of Na+ and K+ were increased, resulting in an increased osmotic excretion rate (V=7.9 plus or minus 0.9, FC=6.1 plus or minus 0.7 and F=13.5 plus or minus 0.7 uOsm/min). Creatinine excretion rate was increased over the first two postflight days. In the absence of changes in plasma creatinine, Na+, or K+ (samples obtained immediately post flight from similar rats compared to Day 14), GFR was increased following space flight. The increased excretion of solute was thus the result of increased delivery and decreased reabsorption. Osmotic clearance was increased (V=28, FC=27 and F=51 microliter/min), while free water clearance was decreased post flight (V=-21,FC=-18 and F=-34 microliter/min). In rats, the postflight diuresis is the result of an increase in solute (osmotic) excretion with an accompanying reduction in free water clearance.

  14. Impairment of renal sodium excretion in tropical residents - phenomenological analysis

    NASA Astrophysics Data System (ADS)

    Arthur, S. K.; Aryee, P. A.; Amuasi, J.; Hesse, I. F. A.; Affram, R. K.

    There is evidence of impaired renal sodium excretion in salt-sensitive African Blacks. A decreased rate of renal sodium chloride (NaCl) excretion, low plasma renin activity and a tendency to elevated blood pressure are the hallmarks of salt sensitivity. Recent evidence indicates that increased proximal and distal tubular fluid reabsorption in some tropical residents may explain the impaired sodium excretion in these people. In this study of a cohort population, we speculated that subjects selected from that population might be salt-sensitive. We therefore measured the sodium balance in 10 normotensive male subjects over 10 consecutive days, after they had ingested a normal or a high amount of sodium, as NaCl (salt) in their diet. We quantified their renal sodium excretion rate by phenomenological analysis of their sodium balance data. We also measured plasma renin activity for 7 consecutive days in a separate group of 6 male and 4 female subjects in order to assess the state of their renin/angiotensin system. We selected all our subjects from a cohort population of 269 subjects randomly selected from a community known to have a high prevalence of primary hypertension. Our data on two separate groups of subjects from the same cohort population revealed delayed renal sodium excretion with t1/2 of about 5 days, compared to published data for normal individuals with t1/2 of less than 24 h. Also, plasma renin activity levels were low. Hence, our subjects are salt-sensitive. Quantification of their renal impairment is important for various reasons: it heightens one's appreciation of the problem of salt retention in African Blacks who are salt-sensitive and it also underlines the importance of the need for further research into the benefits of dietary salt restriction for reducing cardiovascular mortality in African populations, as has been done in some Western countries.

  15. Urinary Albumin Excretion and Vascular Function in Rheumatoid Arthritis

    PubMed Central

    2016-01-01

    Rheumatoid arthritis (RA) is associated with significant cardiovascular (CV) morbidity and mortality. Increased urinary albumin excretion is a marker of CV risk. There are only few data on urinary albumin excretion in RA patients. Aim of the present study was to investigate urinary albumin excretion in RA patients and analyze, whether there is an association between urinary albumin excretion and vascular function as measured by the augmentation index (AIx). In a total of 341 participants (215 with RA, 126 without RA) urinary albumin-creatinine ratio (ACR) was determined and the AIx was measured. The Kolmogorov-Smirnov-test was used to cluster patient groups whose distributions of ACR can be considered to be equal. A crude analysis showed a median ACR of 6.6 mg/g in the RA group and 5.7 mg/g in patients without RA (P > 0.05). In order to account for diabetes (DM) we formed 4 distinct patient groups. Group 1: RA-/DM- (n = 74); group 2: RA+/DM- (n = 195); group 3: RA-/DM+ (n = 52); group 4: RA+/DM+ (n = 20). Clustering of these groups revealed two distinct patient groups: those without RA and DM, and those with either RA or DM or both. The latter group showed statistically significant higher ACR (median 8.1 mg/g) as the former (median 4.5 mg/g). We found no significant correlation between AIx and ACR. Urinary albumin excretion in patients with RA or DM or both is higher than in subjects without RA and DM. This can be seen as a sign of vascular alteration and increased CV risk in these patients. PMID:26955238

  16. Intake and urinary excretion of sodium chloride under varying conditions of effort and environment heat

    NASA Technical Reports Server (NTRS)

    Zohar, E.; Adar, R.; Tennenbaum, J.; Kesten, M.

    1982-01-01

    Intake and urinary excretion of sodium were investigated in a group of young, healthy and acclimated men. The sodium excretions of workers and of machinists in the engine rooms of a ship were also investigated.

  17. Plasma pharmacokinetics, faecal excretion and efficacy of pyrantel pamoate paste and granule formulations following per os administration in donkeys naturally infected with intestinal strongylidae.

    PubMed

    Gokbulut, Cengiz; Aksit, Dilek; Smaldone, Giorgio; Mariani, Ugo; Veneziano, Vincenzo

    2014-09-15

    The plasma disposition, faecal excretion and efficacy of two formulations of pyrantel pamoate in donkeys were examined in a controlled trial. Three groups of seven donkeys received either no medication (control) or pyrantel paste or granule formulations at horse dosage of 20mg/kg B.W. (equals 6.94 mg/kg PYR base) of body weight. Heparinized blood and faecal samples were collected at various times between 1 and 144 h after treatment. The samples were analysed by high-performance liquid chromatography. The last detectable plasma concentration (tmax) of paste formulation was significantly earlier (36.00 h) compared with granule formulation (46.29 h). Although, there was no significant difference on terminal half lives (t1/2: 12.39 h vs. 14.86 h), tmax (14.86 h vs. 14.00) and MRT (24.80 h vs. 25.44 h) values; the Cmax (0.09 μg/ml) AUC (2.65 μgh/ml) values of paste formulation were significantly lower and smaller compared with those of granule formulation (0.21 μg/ml and 5.60 μgh/ml), respectively. The highest dry faecal concentrations were 710.46 μg/g and 537.21 μg/g and were determined at 48 h for both paste and granule formulation of PYR in donkeys, respectively. Pre-treatment EPG of 1104, 1061 and 1139 were observed for the control, PYR paste and PYR granule groups, respectively. Pre-treatment EPG were not significantly different (P>0.1) between groups. Post-treatment EPG for both PYR treatment groups were significantly different (P<0.001) from the control group until day 35. Following treatments the PYR formulations were efficient (>95% efficacy) until day 28. In all studied donkeys, coprocultures performed at day-3 revealed the presence of Cyathostomes, S. vulgaris. Faecal cultures performed on different days from C-group confirmed the presence of the same genera. Coprocultures from treated animals revealed the presence of few larvae of Cyathostomes.

  18. Prediction and evaluation of urine and urinary nitrogen and mineral excretion from dairy cattle.

    PubMed

    Nennich, T D; Harrison, J H; VanWieringen, L M; St-Pierre, N R; Kincaid, R L; Wattiaux, M A; Davidson, D L; Block, E

    2006-01-01

    Urine excretion is a substantial factor in the amount of manure that needs to be managed, and urinary N can contribute to ammonia volatilization. Development and validation of prediction equations focusing on dietary factors to decrease urine and urinary nutrient excretion will provide information for managing urine and feces separately or for other future technologies. The objective of this study was to develop equations for prediction of urine excretion and excretion of urinary N, Na, and K and to evaluate both new and previously published prediction equations for estimation of urine and urinary nutrient excretion from lactating dairy cows. Data sets from metabolism studies conducted at Washington State University were compiled and evaluated for excretion of minerals. Urine excretion averaged 24.1 kg/d and urinary nitrogen excretion ranged from 63 to 499 g/d in the calibration data set. Regression equations were developed to predict urine excretion, urinary N excretion, and urinary Na and K excretion. Predictors used in the regression equations included milk yield, body weight, dietary crude protein percentage, milk urea nitrogen, and nutrient intakes. Previously published prediction equations were evaluated using data sets from Washington State University and the University of Wisconsin. Mean and linear biases were evaluated by determining the regression of residuals on predicted values. Evaluation and validation of prediction equations are important to develop equations that will more accurately estimate urine and urinary nitrogen excretion from lactating dairy cows.

  19. Salivary excretion of rabies virus by healthy vampire bats.

    PubMed

    Aguilar-Setien, A; Loza-Rubio, E; Salas-Rojas, M; Brisseau, N; Cliquet, F; Pastoret, P P; Rojas-Dotor, S; Tesoro, E; Kretschmer, R

    2005-06-01

    Salivary excretion of rabies virus was evaluated in 14 adult vampire bats (Desmodus rotundus) intramuscularly injected with a large dose (10(6) MICLD50) of vampire rabies virus variant CASS88. Saliva samples were obtained from surviving bats every other day for 30 days, then weekly for 2 months, and finally 1 and 2 years later. Rabies virus was isolated in murine neuroblastoma cells and in randomly selected cases by PCR. Rabies virus was not detected in the saliva of any of the 11 animals that succumbed (somewhat early) to rabies challenge, nor in the control bats. In contrast, virus was detected early, and only once (days 6, 6 and 21) in each of the three animals that survived rabies challenge and remained healthy for at least 2 years after challenge. At that time even vigorous dexamethasone and cyclosporine administration failed to provoke further viral excretion.

  20. Krill excretion boosts microbial activity in the Southern Ocean.

    PubMed

    Arístegui, Javier; Duarte, Carlos M; Reche, Isabel; Gómez-Pinchetti, Juan L

    2014-01-01

    Antarctic krill are known to release large amounts of inorganic and organic nutrients to the water column. Here we test the role of krill excretion of dissolved products in stimulating heterotrophic bacteria on the basis of three experiments where ammonium and organic excretory products released by krill were added to bacterial assemblages, free of grazers. Our results demonstrate that the addition of krill excretion products (but not of ammonium alone), at levels expected in krill swarms, greatly stimulates bacteria resulting in an order-of-magnitude increase in growth and production. Furthermore, they suggest that bacterial growth rate in the Southern Ocean is suppressed well below their potential by resource limitation. Enhanced bacterial activity in the presence of krill, which are major sources of DOC in the Southern Ocean, would further increase recycling processes associated with krill activity, resulting in highly efficient krill-bacterial recycling that should be conducive to stimulating periods of high primary productivity in the Southern Ocean.

  1. Salivary excretion of rabies virus by healthy vampire bats.

    PubMed Central

    Aguilar-Setien, A.; Loza-Rubio, E.; Salas-Rojas, M.; Brisseau, N.; Cliquet, F.; Pastoret, P. P.; Rojas-Dotor, S.; Tesoro, E.; Kretschmer, R.

    2005-01-01

    Salivary excretion of rabies virus was evaluated in 14 adult vampire bats (Desmodus rotundus) intramuscularly injected with a large dose (10(6) MICLD50) of vampire rabies virus variant CASS88. Saliva samples were obtained from surviving bats every other day for 30 days, then weekly for 2 months, and finally 1 and 2 years later. Rabies virus was isolated in murine neuroblastoma cells and in randomly selected cases by PCR. Rabies virus was not detected in the saliva of any of the 11 animals that succumbed (somewhat early) to rabies challenge, nor in the control bats. In contrast, virus was detected early, and only once (days 6, 6 and 21) in each of the three animals that survived rabies challenge and remained healthy for at least 2 years after challenge. At that time even vigorous dexamethasone and cyclosporine administration failed to provoke further viral excretion. PMID:15966107

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

    PubMed

    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

  3. Excretion and metabolism of nikethamide in the horse.

    PubMed Central

    Delbeke, F. T.; Debackere, M.

    1976-01-01

    It is well known that nikethamide (N,N-diethylnicotinamide, CoramineR) is metabolized very rapidly to nicotinamide. Hence, there is difficulty in proving that nikethamide has been used as a doping substance because nicotinamide is a normal physiological metabolite in the organism as well as a vitamin preparation. However, an intermediate metabolite (N-ethylnicotinamide) was found by us in the urine of horses treated with CoramineR. This was characterized by gas chromatography/mass spectrometry, and synthesized and identified as being N-ethylnicotinamide. The excretion and metabolism of nikethamide after intramuscular injection in the horse was followed using quantitative gas chromatography of urine extracts over a period of several hours and the results of these experiments are reported. Changes in urinary pH had no significant effect upon either the metabolism or rate of excretion of the drug. PMID:11864

  4. Proteomic analysis of Taenia solium metacestode excretion-secretion proteins.

    PubMed

    Victor, Bjorn; Kanobana, Kirezi; Gabriël, Sarah; Polman, Katja; Deckers, Nynke; Dorny, Pierre; Deelder, André M; Palmblad, Magnus

    2012-06-01

    The metacestode larval stage of Taenia solium is the causal agent of a zoonotic disease called cysticercosis. The disease has an important impact on pork trade (due to porcine cysticercosis) and public health (due to human neurocysticercosis). In order to improve the current diagnostic tools and to get a better understanding of the interaction between T. solium metacestodes and their host, there is a need for more information about the proteins that are released by the parasite. In this study, we used protein sequences from different helminths, 1DE, reversed-phase LC, and MS/MS to analyze the excretion-secretion proteins produced by T. solium metacestodes from infected pigs. This is the first report of the T. solium metacestode excretion-secretion proteome. We report 76 proteins including 27 already described T. solium proteins, 17 host proteins and 32 proteins likely to be of T. solium origin, but identified using sequences from other helminths.

  5. Salivary excretion of rabies virus by healthy vampire bats.

    PubMed

    Aguilar-Setien, A; Loza-Rubio, E; Salas-Rojas, M; Brisseau, N; Cliquet, F; Pastoret, P P; Rojas-Dotor, S; Tesoro, E; Kretschmer, R

    2005-06-01

    Salivary excretion of rabies virus was evaluated in 14 adult vampire bats (Desmodus rotundus) intramuscularly injected with a large dose (10(6) MICLD50) of vampire rabies virus variant CASS88. Saliva samples were obtained from surviving bats every other day for 30 days, then weekly for 2 months, and finally 1 and 2 years later. Rabies virus was isolated in murine neuroblastoma cells and in randomly selected cases by PCR. Rabies virus was not detected in the saliva of any of the 11 animals that succumbed (somewhat early) to rabies challenge, nor in the control bats. In contrast, virus was detected early, and only once (days 6, 6 and 21) in each of the three animals that survived rabies challenge and remained healthy for at least 2 years after challenge. At that time even vigorous dexamethasone and cyclosporine administration failed to provoke further viral excretion. PMID:15966107

  6. Efficient production of ectoine using ectoine-excreting strain.

    PubMed

    Zhang, Ling-hua; Lang, Ya-jun; Nagata, Shinichi

    2009-07-01

    Halophilic bacteria strain Halomonas salina DSM 5928 was found to excrete ectoine, suggesting its potential in the development of a new method of ectoine production. We performed HPLC and LC-MS analyses that showed that Halomonas salina DSM 5928 excreted ectoine under constant extracellular osmolarity. Medium adopting monosodium glutamate as a sole source of carbon and nitrogen was beneficial for ectoine synthesis. The total concentration of ectoine was not affected by NaCl concentration in the range 0.5-2 mol l(-1). The total concentration of ectoine and productivity in a 10-l fermentor with 0.5 mol l(-1) NaCl were 6.9 g l(-1) and 7.9 g l(-1) d(-1), respectively. These findings show that Halomonas salina DSM 5928 efficiently produces ectoine at relatively low NaCl concentration. This research also indicates the potential application of free or immobilized cells for continuous culture to produce ectoine.

  7. Metabolism and excretion of [14C] verruculogen in a sheep.

    PubMed

    Perera, K P; Mantle, P G; Penny, R H

    1982-05-01

    [14C] Verruculogen (75 micrograms/kg) was given intravenously to a sheep under barbiturate anaesthesia to prevent the severe tremor and convulsions which would otherwise have occurred. Two hours later 28 per cent of the tremorgenic mycotoxin was detected in the liver, bile and small intestine. Approximately 0.5 per cent was excreted in the urine. Trace amounts of radiolabel were detected in the cortex and corpus striatum of the brain. Verruculogen was metabolised by the liver and converted completely to four more polar products, including two isomeric forms of desoxy-verruculogen and the weakly tremorgenic mycotoxin TR-2. The principal and most polar metabolite excreted is probably an isomer of TR-2. PMID:7100651

  8. III. Quantitative aspects of phosphorus excretion in ruminants.

    PubMed

    Bravo, David; Sauvant, Daniel; Bogaert, Catherine; Meschy, François

    2003-01-01

    Ruminant phosphorus excretion and metabolism were studied through a database. Faecal endogenous phosphorus is the main pathway of phosphorus excretion and averages 0.85 of total faecal phosphorus. The remaining 0.15 is unabsorbed dietary phosphorus. Faecal endogenous phosphorus is mainly unabsorbed phosphorus, with saliva being the major source, and is correlated to factors influencing saliva secretion (DM intake, physical dietary characteristics and dietary phosphorus content). Another source of faecal endogenous phosphorus is rumen microbial phosphorus that escaped solubilisation during post-rumen digestion. All factors stimulating microbial growth would increase phosphorus uptake by the rumen microbes and consequently the faecal endogenous phosphorus. Understanding the determinants of faecal endogenous phosphorus flow will help to precise the determination of net phosphorus requirements for maintenance. The role of plasma phosphorus in urinary phosphorus loss is discussed.

  9. [Body mass and excretion of phosphorus in aqueous invertebrates].

    PubMed

    Golubkov, S M

    2014-01-01

    Empirical materials on the dependence of the intensity of mineral phosphorus excretion (Ex) on the body mass (W) in invertebrates are summarized. The parameters of the average dependence of Ex on Win animals at 20 degrees C are determined. The main factors that influence the parameters ofthis dependence are discussed. It is shown that the decrease of Ex with an increase of Win animals is, as a rule, more significant compared with the decrease in the intensity of metabolism.

  10. Factors affecting urinary excretion of testosterone metabolites conjugated with cysteine.

    PubMed

    Fabregat, Andreu; Marcos, Josep; Segura, Jordi; Ventura, Rosa; Pozo, Oscar J

    2016-01-01

    The implementation of the athlete steroidal passport in doping control analysis aims to detect intra-individual changes in the steroid profile related to the abuse of anabolic steroids. In this context, the study of intrinsic variations associated with each marker is of utmost importance. In the present work, the influence of several factors in the excretion of the recently reported testosterone metabolites conjugated with cysteine (Δ(1) -AED; 1,4-androstadien-3,17-dione, Δ(6) -AED; 4,6-androstadien-3,17-dione, Δ(6) -T; 4,6-androstadien-17β-ol-3-one, and Δ(15) -AD; 15-androsten-3,17-dione) is evaluated for the first time. Degradation experiments at 37 °C proved that, although the cysteinyl moiety is released, the variation for urinary Δ(1) -AED/Δ(6) -AED, Δ(1) -AED/Δ(6) -T ratios is less than 30%. Moreover, freeze/thaw cycle testing resulted in RSDs values below 15% for all the analytes. Regarding infradian variability, moderate variations (below 40%) were observed. Additionally, notable alterations in the excretion of these compounds have been observed in the earliest stages of pregnancy. UGT2B17 polymorphism, responsible for the low T/E ratio found in some population, does not influence the excretion of cysteinyl compounds whereas the intake of exogenous substances (alcohol or 5α-reductase inhibitors) dramatically affects their excretion. The urinary concentrations of Δ(1) -AED, Δ(6) -AED, and Δ(15) -AD decreased (<50 %) after the ethanol intake, whereas after the administration of dutasteride, an important increase was observed for the concentrations of Δ(6) -AED, Δ(6) -T and Δ(15) -AD. Overall, the presented data describes the stability of the urinary cysteinyl steroids under the influence of many factors, proving their potential as suitable parameters to be included in the steroidal module of the athlete's biological passport. PMID:25917157

  11. Factors affecting urinary excretion of testosterone metabolites conjugated with cysteine.

    PubMed

    Fabregat, Andreu; Marcos, Josep; Segura, Jordi; Ventura, Rosa; Pozo, Oscar J

    2016-01-01

    The implementation of the athlete steroidal passport in doping control analysis aims to detect intra-individual changes in the steroid profile related to the abuse of anabolic steroids. In this context, the study of intrinsic variations associated with each marker is of utmost importance. In the present work, the influence of several factors in the excretion of the recently reported testosterone metabolites conjugated with cysteine (Δ(1) -AED; 1,4-androstadien-3,17-dione, Δ(6) -AED; 4,6-androstadien-3,17-dione, Δ(6) -T; 4,6-androstadien-17β-ol-3-one, and Δ(15) -AD; 15-androsten-3,17-dione) is evaluated for the first time. Degradation experiments at 37 °C proved that, although the cysteinyl moiety is released, the variation for urinary Δ(1) -AED/Δ(6) -AED, Δ(1) -AED/Δ(6) -T ratios is less than 30%. Moreover, freeze/thaw cycle testing resulted in RSDs values below 15% for all the analytes. Regarding infradian variability, moderate variations (below 40%) were observed. Additionally, notable alterations in the excretion of these compounds have been observed in the earliest stages of pregnancy. UGT2B17 polymorphism, responsible for the low T/E ratio found in some population, does not influence the excretion of cysteinyl compounds whereas the intake of exogenous substances (alcohol or 5α-reductase inhibitors) dramatically affects their excretion. The urinary concentrations of Δ(1) -AED, Δ(6) -AED, and Δ(15) -AD decreased (<50 %) after the ethanol intake, whereas after the administration of dutasteride, an important increase was observed for the concentrations of Δ(6) -AED, Δ(6) -T and Δ(15) -AD. Overall, the presented data describes the stability of the urinary cysteinyl steroids under the influence of many factors, proving their potential as suitable parameters to be included in the steroidal module of the athlete's biological passport.

  12. ABCG2 dysfunction increases serum uric acid by decreased intestinal urate excretion.

    PubMed

    Takada, Tappei; Ichida, Kimiyoshi; Matsuo, Hirotaka; Nakayama, Akiyoshi; Murakami, Keizo; Yamanashi, Yoshihide; Kasuga, Hiroshi; Shinomiya, Nariyoshi; Suzuki, Hiroshi

    2014-01-01

    ATP-binding cassette transporter G2 (ABCG2), also known as breast cancer resistance protein (BCRP), is identified as a high-capacity urate exporter and its dysfunction has an association with serum uric acid (SUA) levels and gout/hyperuricemia risk. However, pathophysiologically important pathway(s) responsible for the ABCG2-mediated urate excretion were unknown. In this study, we investigated how ABCG2 dysfunction affected the urate excretion pathways. First, we revealed that mouse Abcg2 mediates urate transport using the membrane vesicle system. The export process by mouse Abcg2 was ATP-dependent and not saturable under the physiological concentration of urate. Then, we characterized the excretion of urate into urine, bile, and intestinal lumen using in vivo mouse model. SUA of Abcg2-knockout mice was significantly higher than that of control mice. Under this condition, the renal urate excretion was increased in Abcg2-knockout mice, whereas the urate excretion from the intestine was decreased to less than a half. Biliary urate excretion showed no significant difference regardless of Abcg2 genotype. From these results, we estimated the relative contribution of each pathway to total urate excretion; in wild-type mice, the renal excretion pathway contributes approximately two-thirds, the intestinal excretion pathway contributes one-third of the total urate excretion, and the urate excretion into bile is minor. Decreased intestinal excretion could account for the increased SUA of Abcg2-knockout mice. Thus, ABCG2 is suggested to have an important role in extra-renal urate excretion, especially in intestinal excretion. Accordingly, increased SUA in patients with ABCG2 dysfunction could be explained by the decreased excretion of urate from the intestine.

  13. Urinary excretion of morphine and biosynthetic precursors in mice

    PubMed Central

    Grobe, Nadja; Lamshöft, Marc; Orth, Robert G.; Dräger, Birgit; Kutchan, Toni M.; Zenk, Meinhart H.; Spiteller, Michael

    2010-01-01

    It has been firmly established that humans excrete a small but steady amount of the isoquinoline alkaloid morphine in their urine. It is unclear whether it is of dietary or endogenous origin. There is no doubt that a simple isoquinoline alkaloid, tetrahydropapaveroline (THP), is found in human and rodent brain as well as in human urine. This suggests a potential biogenetic relationship between both alkaloids. Unlabeled THP or [1,3,4-D3]-THP was injected intraperitoneally into mice and the urine was analyzed. This potential precursor was extensively metabolized (96%). Among the metabolites found was the phenol-coupled product salutaridine, the known morphine precursor in the opium poppy plant. Synthetic [7D]-salutaridinol, the biosynthetic reduction product of salutaridine, injected intraperitoneally into live animals led to the formation of [7D]-thebaine, which was excreted in urine. [N-CD3]-thebaine was also administered and yielded [N-CD3]-morphine and the congeners [N-CD3]-codeine and [N-CD3]-oripavine in urine. These results show for the first time that live animals have the biosynthetic capability to convert a normal constituent of rodents, THP, to morphine. Morphine and its precursors are normally not found in tissues or organs, presumably due to metabolic breakdown. Hence, only that portion of the isoquinoline alkaloids excreted in urine unmetabolized can be detected. Analysis of urine by high resolution-mass spectrometry proved to be a powerful method for tracking endogenous morphine and its biosynthetic precursors. PMID:20421505

  14. Urinary excretion of morphine and biosynthetic precursors in mice.

    PubMed

    Grobe, Nadja; Lamshöft, Marc; Orth, Robert G; Dräger, Birgit; Kutchan, Toni M; Zenk, Meinhart H; Spiteller, Michael

    2010-05-01

    It has been firmly established that humans excrete a small but steady amount of the isoquinoline alkaloid morphine in their urine. It is unclear whether it is of dietary or endogenous origin. There is no doubt that a simple isoquinoline alkaloid, tetrahydropapaveroline (THP), is found in human and rodent brain as well as in human urine. This suggests a potential biogenetic relationship between both alkaloids. Unlabeled THP or [1,3,4-D(3)]-THP was injected intraperitoneally into mice and the urine was analyzed. This potential precursor was extensively metabolized (96%). Among the metabolites found was the phenol-coupled product salutaridine, the known morphine precursor in the opium poppy plant. Synthetic [7D]-salutaridinol, the biosynthetic reduction product of salutaridine, injected intraperitoneally into live animals led to the formation of [7D]-thebaine, which was excreted in urine. [N-CD(3)]-thebaine was also administered and yielded [N-CD(3)]-morphine and the congeners [N-CD(3)]-codeine and [N-CD(3)]-oripavine in urine. These results show for the first time that live animals have the biosynthetic capability to convert a normal constituent of rodents, THP, to morphine. Morphine and its precursors are normally not found in tissues or organs, presumably due to metabolic breakdown. Hence, only that portion of the isoquinoline alkaloids excreted in urine unmetabolized can be detected. Analysis of urine by high resolution-mass spectrometry proved to be a powerful method for tracking endogenous morphine and its biosynthetic precursors.

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

    PubMed

    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 <32 weeks and body weight <1500 g, were included in the study. Demographic and clinical data were recorded, within the first 72 h of life and urine and blood samples were collected for the measurement of urinary aldosterone and serum potassium, sodium, and chloride. The mean UAE 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

  16. Urinary Kallikrein Excretion in Essential and Mineralocorticoid Hypertension

    PubMed Central

    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 deficiency), and in normal subjects of the same race. No significant difference in urinary kallikrein excretion of patients with LREH vs. normal renin essential hypertension (NREH) was found for either black (4.1±0.4 vs. 4.8±0.5 esterase units (EU)/24 h, mean±SE, for 27 LREH and 38 NREH, respectively) or white patients (12.2±2.3 vs. 11.7±1.4 EU/24 h for 13 LREH and 25 NREH, respectively). Urinary kallikrein was decreased in black vs. white hypertensive patients and normal subjects. However, in patients with normal renal function (creatinine clearance ≥80 ml/min) urinary kallikrein was not significantly decreased in either black hypertensive vs. black normal subjects (4.3±0.3 vs. 5.4±0.6 EU/24 h) or in white hypertensive vs. white normal subjects (11.9±1.2 vs. 8.4±0.9 EU/24 h). In contrast, hypertensive patients with mild renal insufficiency (creatinine clearance of 41.8±78.5 ml/min) had reduced (P < 0.05) urinary kallikrein (3.3 EU/24 h with creatinine clearance of 63.6±2.0 for 24 black patients and 4.2±0.7 EU/24 h with creatinine clearance of 67.0±3.5 for 6 white patients). These results suggest that a reduction in urinary kallikrein excretion rate is an early accompaniment of hypertensive renal injury. Urinary kallikrein excretion in response to a 6-d 10-meq sodium diet and a 3-d Florinef (0.5 mg b.i.d.) administration was compared in hypertensive patients with normal renal function vs. race and age-matched normal subjects. Stimulation of urinary kallikrein

  17. Decabromodiphenyl ether in the rat: absorption, distribution, metabolism, and excretion.

    PubMed

    Morck, Anna; Hakk, Heldur; Orn, Ulrika; Klasson Wehler, Eva

    2003-07-01

    Among the group of polybrominated diphenyl ethers used as flame-retardants, the fully brominated diphenyl ether, decabromodiphenyl ether (decaBDE), is the most commonly used. Despite the large usage of decaBDE, neither the metabolic pathways nor the absorption have been addressed, and there are very few studies on its toxicology. In this work, it is shown that after a single oral dose of 14C-labeled decaBDE to rats, at least 10% of the decaBDE dose is absorbed. The major excretion route in conventional rats is via feces that contained 90% of the decaBDE dose. The excretion in bile was close to 10% of the dose and represented mainly metabolites. It cannot be excluded that greater than 10% of the oral dose had been absorbed since 65% of the radioactivity excreted in feces was metabolites. The highest concentrations on a lipid weight basis were found in plasma and blood-rich tissues, and the adipose tissue had the lowest concentration of decaBDE. After derivatization of a phenolic fraction, gas chromatography-mass spectrometry (GC/MS) analyses indicated that metabolites with five to seven bromine atoms had formed, and they possessed a guaiacol structure (a hydroxy and a methoxy group) in one of the rings. In addition, traces of nonabrominated diphenyl ethers and monohydroxylated metabolites were found by GC/MS. Metabolites, characterized by their chemical properties, were interpreted to be covalently bound to macromolecules, either proteins or lipids. In addition, water solubility was suggested. The metabolic pathway was indicated to include a reactive intermediate. PMID:12814967

  18. Urine Creatinine Excretion and Clinical Outcomes in CKD

    PubMed Central

    Di Micco, Lucia; Quinn, Robert Ross; Ronksley, Paul Everett; Bellizzi, Vincenzo; Lewin, Adriane Marlene; Cianciaruso, Bruno

    2013-01-01

    Summary Background and objectives Twenty-four–hour urine creatinine excretion is a reliable approximation of muscle mass. Whether changes in urine creatinine predict clinical outcomes in persons with CKD is unknown. This work studied the relationship between urine creatinine and patient and renal survival in people with CKD not requiring renal replacement therapy. Design, setting, participants, & measurements This longitudinal cohort study included incident stages 3–5 CKD patients referred to the renal clinic at the University Federico II in Naples between January of 1995 and December of 2005. Clinical data and urine creatinine were updated at each visit. Main outcomes were all-cause mortality and kidney failure requiring dialysis. Results This study enrolled 525 individuals and followed them for a median of 6 years (range of 4 months to 15 years). Urine creatinine excretion declined by 16 mg/d per year (95% confidence interval, 14 to 19) in participants with CKD stages 3a, 3b, and 4, and it remained stable in participants with stage 5 CKD. Per each 20 mg/d decline in urine creatinine, mortality increased by 3% (adjusted hazard ratio, 1.03; 95% confidence interval, 1.01 to 1.05), and the risk of initiating dialysis increased by 2% (adjusted hazard ratio, 1.02; 95% confidence interval, 1.01 to 1.03). These associations were independent of body mass index and GFR. Conclusions In persons with CKD stages 3 and 4, urine creatinine declines at a rate of 16 mg/d per year. Lower urine creatinine excretion predicts greater risk of kidney failure and patient mortality. PMID:24158796

  19. Iron excretion in iron dextran-overloaded mice

    PubMed Central

    Musumeci, Marco; Maccari, Sonia; Massimi, Alessia; Stati, Tonino; Sestili, Paola; Corritore, Elisa; Pastorelli, Augusto; Stacchini, Paolo; Marano, Giuseppe; Catalano, Liviana

    2014-01-01

    Background Iron homeostasis in humans is tightly regulated by mechanisms aimed to conserve iron for reutilisation, with a negligible role played by excretory mechanisms. In a previous study we found that mice have an astonishing ability to tolerate very high doses of parenterally administered iron dextran. Whether this ability is linked to the existence of an excretory pathway remains to be ascertained. Materials and methods Iron overload was generated by intraperitoneal injections of iron dextran (1 g/kg) administered once a week for 8 weeks in two different mouse strains (C57bl/6 and B6D2F1). Urinary and faecal iron excretion was assessed by inductively coupling plasma-mass spectrometry, whereas cardiac and liver architecture was evaluated by echocardiography and histological methods. For both strains, 24-hour faeces and urine samples were collected and iron concentration was determined on days 0, 1 and 2 after iron administration. Results In iron-overloaded C57bl/6 mice, the faecal iron concentration increased by 218% and 157% on days 1 and 2, respectively (p<0.01). The iron excreted represented a loss of 14% of total iron administered. Similar but smaller changes was also found in B6D2F1 mice. Conversely, we found no significant changes in the concentration of iron in the urine in either of the strains of mice. In both strains, histological examination showed accumulation of iron in the liver and heart which tended to decrease over time. Conclusions This study indicates that mice have a mechanism for removal of excess body iron and provides insights into the possible mechanisms of excretion. PMID:24960657

  20. Chlordecone impaired biliary excretion: In vivo and in vitro correlates

    SciTech Connect

    Rochelle, L.G.

    1989-01-01

    The focus of this research was to investigate mechanisms of impaired biliary excretion localized to the bile canaliculus. Two modes of chlordecone (CD) action were investigated: (1) direct effects on organic anion transport at the bile canaliculus; and/or (2) general membrane perturbation, indirectly affecting anion transport proteins. Bile canaliculi-enriched fractions (BCEF) were isolated from rat livers in order to characterize effects of CD on this domain of the plasma membranes. CD inhibited the initial rate leading to a peak Na{sup +}-stimulated ({sup 3}H)L-glutamate uptake in BCEF CD inhibition of the initial or Na{sup +}-gradient driven phase of ({sup 3}H)L-glutamate uptake suggested that CD was affecting maintenance of the Na{sup +}-gradient by the BCEF membrane vesicles. In vivo PG anion excretion was inhibited as well as in vitro ({sup 3}H)L-glutamate transport at 24 hr following in vivo CD treatment of rats. Seventy-two hr following CD treatment, rats recovered to control PG excretion levels. PG excretory performance was regained in 72 hr pretreated rats despite an increase in liver CD concentration. Liver CD concentrations in 24 hr pretreated rats were approximately 50% of the concentrations in 72 hr pretreated rats. At low CD concentrations, there was no evidence of general membrane perturbation in terms of immobilization of the lipid electron spin resonance probe, 16-doxyl stearate, in BCEF. Mobility of 16-doxyl stearate in BCEF was reduced at in vitro CD concentrations of 0.20 {mu}mol/mg protein or greater. CD did reduce hepatobiliary permeability to ({sup 14}C)mannitol in 24 and 72 hr pretreated rats; perhaps restricting movement through membrane aqueous pores.

  1. Enantioselective renal excretion of albendazole metabolites in patients with neurocysticercosis.

    PubMed

    Lanchote, V L; Takayanagui, O M; Mateus, F H

    2004-10-01

    The present study investigates the urinary excretion of the enantiomers of (+)- and (-)-albendazole sulfoxide (ASOX) and albendazole sulfone (ASON) in 12 patients with neurocysticercosis treated with albendazole for 8 days (7.5 mg/kg/12 h). Serial blood samples (0-12 h) and urine (three periods of 8 h) were collected after administration of the last dose of albendazole. Plasma and urine (+)-ASOX, (-)-ASOX, and ASON metabolites were determined by HPLC using a chiral phase column (Chiralpak AD) with fluorescence detection. The pharmacokinetic parameters (P < 0.05) for (+)-ASOX, (-)-ASOX, and ASON metabolites are reported as means (95% CI); amount excreted (Ae) = 3.19 (1.53-4.85) vs. 0.72 (0.41-1.04) vs. 0.08 (0.03-0.13) mg; plasma concentration-time area under the curve, AUC(0-24) = 3.56 (0.93-6.18) vs. 0.60 (0.12-1.08) vs. 0.38 (0.20-0.55) microg x h/ml, and renal clearance Cl(R) = 1.20 (0.66-1.73) vs. 2.72 (0.39-5.05) vs. 0.25 (0.13-0.37) l/h. Sulfone formation capacity, expressed as the Ae ratio ASON/ASOX + ASON, was 2.21 (1.43-2.99). These data point to enantioselectivity in the renal excretion of ASOX as a complementary mechanism to the metabolism responsible for the plasma accumulation of (+)-ASOX. The results also suggest that the metabolite ASON is partially eliminated as a reaction product of the subsequent metabolism.

  2. Episodic ventilation lowers the efficiency of pulmonary CO2 excretion.

    PubMed

    Malte, Christian Lind; Malte, Hans; Wang, Tobias

    2013-11-01

    The ventilation pattern of many ectothermic vertebrates, as well as hibernating and diving endotherms, is episodic where breaths are clustered in bouts interspersed among apneas of varying duration. Using mechanically ventilated, anesthetized freshwater turtles (Trachemys scripta), a species that normally exhibits this episodic ventilation pattern, we investigated whether episodic ventilation affects pulmonary gas exchange compared with evenly spaced breaths. In two separate series of experiments (a noninvasive and an invasive), ventilation pattern was switched from a steady state, with evenly spaced breaths, to episodic ventilation while maintaining overall minute ventilation (30 ml·min(-1)·kg(-1)). On switching to an episodic ventilation pattern of 10 clustered breaths, mean CO2 excretion rate was reduced by 6 ± 5% (noninvasive protocol) or 20 ± 8% (invasive protocol) in the first ventilation pattern cycle, along with a reduction in the respiratory exchange ratio. O2 uptake was either not affected or increased in the first ventilation pattern cycle, while neither heart rate nor overall pulmonary blood flow was significantly affected by the ventilation patterns. The results confirm that, for a given minute ventilation, episodic ventilation is intrinsically less efficient for CO2 excretion, thereby indicating an increase in the total bodily CO2 store in the protocol. Despite the apparent CO2 retention, mean arterial Pco2 only increased 1 Torr during the episodic ventilation pattern, which was concomitant with a possible reduction of respiratory quotient. This would indicate a shift in metabolism such that less CO2 is produced when the efficiency of excretion is reduced. PMID:23970538

  3. [Immunohistochemical study on the mechanism of excretion of methamphetamine].

    PubMed

    Kajitani, A; Kaiho, M; Mori, A; Okada, Y; Mukaida, M; Ishiyama, I

    1989-06-01

    Many methods of analysis are available to the forensic toxicologist for determining the amount of methamphetamine within human tissues, but few have the potential of histochemistry for enabling the precise site of excretion of methamphetamine to be defined. We have established a method for the demonstration of methamphetamine by immunohistochemistry, and applied this method for showing morphologically the disposition of methamphetamine. The following cells in the tissues of methamphetamine-intoxicated mice gave a strong positive reaction of the localization, which was thought to be the histological evidence of excretion of this drug: epithelial cells of the distal part of the renal tubule and of the collecting tubule, transitional epithelial cells of the bladder, liver parenchymal cells, epithelial cells of the striated duct of the salivary gland, parietal cells of the gastric gland, part of epithelial cells of the distal portion of the large intestine, secretory cells and part of epithelial cells of the ductal portion of the sweat gland, alveolar cells of the mammary gland, secretory cells of the sebaceous gland and hair medulla and cortex. These results indicated passive diffusion of methamphetamine across membranes of the cells of the distal tubule and collecting tubule of the kidney, of the bladder and of the striated duct of the salivary gland. In the parietal cells of the gastric gland, part of epithelial cells of the distal portion of the large intestine and secretory cells of the sweat gland, methamphetamine was thought to be stored and subsequently released. In the mammary gland, methamphetamine was found to be combined with casein and excreted by exocytosis. Accumulation of methamphetamine in the hair was supposed to be chiefly due to the penetration of this drug derived from tissue fluid and sebum.

  4. Value of estimating methylamalonic acid excretion in anaemia.

    PubMed

    Green, A E; Pegrum, G D

    1968-09-01

    A rapid technique suitable for routine pathology laboratories has been used to estimate methylmalonic acid excretion in a 24-hour urine collection following a 10g. valine load. Levels above 40 mg./24 hours were found only in patients with vitamin B(12) deficiency. Patients with pernicious anaemia treated more than 24 hours before urine collection and patients with other types of anaemia had methylmalonic acid levels below 25 mg./24 hours.This method of demonstrating vitamin B(12) deficiency can be applied rapidly in debilitated patients so that specific treatment can be instituted within 36 hours of admission.

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

    SciTech Connect

    Hedrick, W.R.; Di Simone, R.N.; Keen, R.L.

    1986-10-01

    Measurements were made of the activity in samples of breast milk obtained from a patient with postpartum thyroiditis following administration of (/sup 123/I)sodium iodide and subsequently (99mTc)pertechnetate 24 hr later. Both /sup 123/I 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 (/sup 123/I)sodium iodide breast feeding should be discontinued for 24-36 hr to reduce the absorbed dose to the child's thyroid.

  6. [The effect of aldosterone A on renal potassium excretion].

    PubMed

    Winther, Signe Abitz; Egfjord, Martin

    2011-01-10

    Recent studies have shown expression of the following regulatory WNK kinases in the kidney: the full-length WNK1 (L-WNK1), the shorter kidney specific WNK1 transcript (KS-WNK1), formed by alternative splicing, and WNK4. Aldosterone activates expression of KS-WNK1 and inhibits WNK4 via SGK1 - both leading to stimulation of ENaC and activation of ROMK, and increased potassium excretion. Thus, further characterization of the WNK system may lead to elucidation of the dual anti-natriuretic and kaliuretic effects of aldosterone, in situations where only activation of one of these effects is needed. PMID:21219845

  7. Quantitative estimation of urinary protein excretion by refractometry.

    PubMed

    Kumar, S; Visweswaran, K; Sobha, A; Sarasa, G; Nampoory, M R

    1992-09-01

    Quantitative estimation of proteinuria done by the refractometric method was compared with that done by the sulphosalycilic acid method and biuret method in 102 urine samples. The analysis of results by students' t test showed no statistically significant difference between the three methods. It is concluded that quantitative estimation of urinary protein excretion by refractometric method is a simple cheap and reliable method and can be performed easily in the outpatient clinic. The instrument is quite handy and can be carried in the pocket.

  8. Testosterone urinary excretion rate increases during hypergravity in male monkeys

    NASA Technical Reports Server (NTRS)

    Strollo, F.; Barger, L.; Fuller, C.

    2000-01-01

    Real and simulated microgravity impairs T secretion both in animals and in the human. To verify whether hypergravity might enhance T secretion as a consequence of an opposite mechanical effect, 6 male monkeys were centrifuged at 2 G for 3 weeks after a 1 G stabilization period lasting 3 weeks and then taken back to 1 G for 1 week and urine were collected daily for T excretion measurement. Significantly higher level were observed during the initial 2 G phase as compared to pre- and post centrifugation periods and the trend was the same during the remaining 2 G period. This may reflect changes in testicular perfusion rather than endocrine adaptation per se.

  9. Rapid Hepatobiliary Excretion of Micelle-Encapsulated/Radiolabeled Upconverting Nanoparticles as an Integrated Form

    PubMed Central

    Seo, Hyo Jung; Nam, Sang Hwan; Im, Hyung-Jun; Park, Ji-yong; Lee, Ji Youn; Yoo, Byeongjun; Lee, Yun-Sang; Jeong, Jae Min; Hyeon, Taeghwan; Who Kim, Ji; Lee, Jae Sung; Jang, In-Jin; Cho, Joo-Youn; Hwang, Do Won; Suh, Yung Doug; Lee, Dong Soo

    2015-01-01

    In the field of nanomedicine, long term accumulation of nanoparticles (NPs) in the mononuclear phagocyte system (MPS) such as liver is the major hurdle in clinical translation. On the other hand, NPs could be excreted via hepatobiliary excretion pathway without overt tissue toxicity. Therefore, it is critical to develop NPs that show favorable excretion property. Herein, we demonstrated that micelle encapsulated 64Cu-labeled upconverting nanoparticles (micelle encapsulated 64Cu-NOTA-UCNPs) showed substantial hepatobiliary excretion by in vivo positron emission tomography (PET) and also upconversion luminescence imaging (ULI). Ex vivo biodistribution study reinforced the imaging results by showing clearance of 84% of initial hepatic uptake in 72 hours. Hepatobiliary excretion of the UCNPs was also verified by transmission electron microscopy (TEM) examination. Micelle encapsulated 64Cu-NOTA-UCNPs could be an optimal bimodal imaging agent owing to quantifiability of 64Cu, ability of in vivo/ex vivo ULI and good hepatobiliary excretion property. PMID:26494465

  10. The significance of nitrate in the nitrogenous excretion of carcinus maenas

    NASA Astrophysics Data System (ADS)

    Spaargaren, D. H.

    Total inorganic-N and NH 4+-N were measured in blood and external media of shore crabs, Carcinus maenas (L.), exposed to various salinities at low (4°C) and high (20°C) temperatures. Total inorganic-N and NH 4+-N were both excreted in larger amounts at lower salinities and at the higher temperature. Nitrate excretion is highest in brackish water and decreases in both higher and lower salinities. Nitrate excretion (0.11-0.72 μmol -1·h -1) was of the same order of magnitude as NH 4 + excretion, but in brackish water NO 3 - excretion predominated, whereas at lower salinities NH 4 + excretion predominated. NO 3 - formation may serve in the detoxification of NH 4 + and the maintenance of electroneutrality. Blood NO 3 - concentrations, like blood NH 4 + concentrations, are strongly stabilized, independent of either temperature or salinity.

  11. [Basic mechanisms: absorption and excretion of cholesterol and other sterols].

    PubMed

    Cofan Pujol, Montserrat

    2014-01-01

    Cholesterol is of vital importance for vertebrate cell membrane structure and function. It is obvious that adequate regulation of cholesterol homeostasis is essential. Hypercholesterolemia promotes atherosclerosis and thereby represents a major risk factor for cardiovascular disease. The liver has been considered the major site of control in maintenance of cholesterol homeostasis. The liver facilitates clearance of (very) low density lipoprotein particles and cholesterol-containing chylomicron remnants, synthesizes cholesterol, synthesizes and secretes (nascent) high density lipoprotein particles, secretes cholesterol and bile salts to bile, and is involved in reverse cholesterol transport. In recent years, however, the importance of the intestine in many aspects of cholesterol physiology is increasingly recognized. It has become apparent that direct secretion of cholesterol from the blood compartment into the intestine, or transintestinal cholesterol excretion, plays a major role in disposal of cholesterol via the feces. This review will discuss current knowledge on the physiology of cholesterol homeostasis, with emphasis on cholesterol absorption, cholesterol synthesis and fecal excretion, and therapeutic options for hypercholesterolemia. PMID:24461630

  12. Effect of chloroquine on the urinary excretion of ciprofloxacin.

    PubMed

    Ilo, Cajetan E; Ezejiofor, Ndidi A; Agbakoba, Nneka; Brown, Sinye A; Maduagwuna, Chinonye A; Agbasi, Patrick U; Orisakwe, Orish E; Orisakweph, Orish E

    2008-01-01

    Ciprofloxacin is an inexpensive antibacterial, whereas chloroquine is an inexpensive antimalarial. The coadministration of chloroquine and ciprofloxacin is easily encountered because both drugs are commonly prescribed to patients in the tropics. Five healthy male volunteers aged 19 to 31 years who were not taking any of the prescribed medications and who had no sensitivity to either ciprofloxacin or chloroquine each received 500 mg ciprofloxacin orally with 250 mL of water, and after a 2-week washout period, 500 mg ciprofloxacin plus 600 mg chloroquine was administered orally with 250 mL of water after providing informed consent. A urine sample (7 mL) was collected just before taking the drug at 8:00 AM representing 0 hour and continued afterward at 1, 2, 4, 8, 12, and 24 hours the next day. The samples were stored at -20 degrees C until analyzed. The minimum inhibitory concentrations by diffusion through agar technique were used for the assay of urine ciprofloxacin. The rate of ciprofloxacin excretion and cumulative urine ciprofloxacin were significantly increased. The coadministration of chloroquine increased the cumulative urinary concentration and excretion rate of ciprofloxacin.

  13. Effect of chloroquine on the urinary excretion of ciprofloxacin.

    PubMed

    Ilo, Cajetan E; Ezejiofor, Ndidi A; Agbakoba, Nneka; Brown, Sinye A; Maduagwuna, Chinonye A; Agbasi, Patrick U; Orisakwe, Orish E; Orisakweph, Orish E

    2008-01-01

    Ciprofloxacin is an inexpensive antibacterial, whereas chloroquine is an inexpensive antimalarial. The coadministration of chloroquine and ciprofloxacin is easily encountered because both drugs are commonly prescribed to patients in the tropics. Five healthy male volunteers aged 19 to 31 years who were not taking any of the prescribed medications and who had no sensitivity to either ciprofloxacin or chloroquine each received 500 mg ciprofloxacin orally with 250 mL of water, and after a 2-week washout period, 500 mg ciprofloxacin plus 600 mg chloroquine was administered orally with 250 mL of water after providing informed consent. A urine sample (7 mL) was collected just before taking the drug at 8:00 AM representing 0 hour and continued afterward at 1, 2, 4, 8, 12, and 24 hours the next day. The samples were stored at -20 degrees C until analyzed. The minimum inhibitory concentrations by diffusion through agar technique were used for the assay of urine ciprofloxacin. The rate of ciprofloxacin excretion and cumulative urine ciprofloxacin were significantly increased. The coadministration of chloroquine increased the cumulative urinary concentration and excretion rate of ciprofloxacin. PMID:18806516

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

    PubMed

    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.

  15. Enhancement of anammox by the excretion of diel vertical migrators

    NASA Astrophysics Data System (ADS)

    Bianchi, Daniele; Babbin, Andrew R.; Galbraith, Eric D.

    2014-11-01

    Measurements show that anaerobic ammonium oxidation with nitrite (anammox) is a major pathway of fixed nitrogen removal in the anoxic zones of the open ocean. Anammox requires a source of ammonium, which under anoxic conditions could be supplied by the breakdown of sinking organic matter via heterotrophic denitrification. However, at many locations where anammox is measured, denitrification rates are small or undetectable. Alternative sources of ammonium have been proposed to explain this paradox, for example through dissimilatory reduction of nitrate to ammonium and transport from anoxic sediments. However, the relevance of these sources in open-ocean anoxic zones is debated. Here, we bring to attention an additional source of ammonium, namely, the daytime excretion by zooplankton and micronekton migrating from the surface to anoxic waters. We use a synthesis of acoustic data to show that, where anoxic waters occur within the water column, most migrators spend the daytime within them. Although migrators export only a small fraction of primary production from the surface, they focus excretion within a confined depth range of anoxic water where particle input is small. Using a simple biogeochemical model, we suggest that, at those depths, the source of ammonium from organisms undergoing diel vertical migrations could exceed the release from particle remineralization, enhancing in situ anammox rates. The contribution of this previously overlooked process, and the numerous uncertainties surrounding it, call for further efforts to evaluate the role of animals in oxygen minimum zone biogeochemistry.

  16. High Salt Diet Affects Renal Sodium Excretion and ERRα Expression

    PubMed Central

    Wang, Dan; Wang, Yang; Liu, Fu-Qiang; Yuan, Zu-Yi; Mu, Jian-Jun

    2016-01-01

    Kidneys regulate the balance of water and sodium and therefore are related to blood pressure. It is unclear whether estrogen-related receptor α (ERRα), an orphan nuclear receptor and transcription factor highly expressed in kidneys, affects the reabsorption of water and sodium. The aim of this study was to determine whether changes in the expressions of ERRα, Na+/K+-ATPase and epithelial sodium channel (ENaC) proteins affected the reabsorption of water and sodium in kidneys of Dahl salt-sensitive (DS) rats. SS.13BN rats, 98% homologous to the DS rats, were used as a normotensive control group. The 24 h urinary sodium excretion of the DS and SS.13BN rats increased after the 6-week high salt diet intervention, while sodium excretion was increased in DS rats with daidzein (agonist of ERRα) treatment. ERRα expression was decreased, while β- and γ-ENaC mRNA expressions were increased upon high sodium diet treatment in the DS rats. In the chromatin immunoprecipitation (CHIP) assay, positive PCR signals were obtained in samples treated with anti-ERRα antibody. The transcriptional activity of ERRα was decreased upon high salt diet intervention. ERRα reduced the expressions of β- and γ-ENaC by binding to the ENaC promoter, thereby increased Na+ reabsorption. Therefore, ERRα might be one of the factors causing salt-sensitive hypertension. PMID:27043552

  17. Urinary oxalate and glycolate excretion and plasma oxalate concentration.

    PubMed Central

    Barratt, T M; Kasidas, G P; Murdoch, I; Rose, G A

    1991-01-01

    The diagnosis of primary hyperoxaluria in young children is hampered by the lack of a reliable reference range for urinary oxalate excretion, especially in infants. We present data on urinary oxalate and glycolate excretion in 137 normal children, on the plasma oxalate concentration in 33 normal children and 53 with chronic renal failure, and on amniotic fluid oxalate concentration in 63 uncomplicated pregnancies. The urinary oxalate:creatinine molar ratios were log normally distributed: mean (range) values were less than 1 year 0.061 (0.015-0.26), 1-5 years 0.036 (0.011-0.12), 5-12 years 0.030 (0.0059-0.15), and greater than 12 years 0.013 (0.0021-0.083). Geometric mean (range) plasma oxalate concentration in the normal children was 1.53 (0.78-3.02) mumols/l and was independent of age. The mean (SD) plasma oxalate: creatinine molar ratio in these normal children and 50 with chronic renal failure was 0.033 (0.013), and was independent of age and renal function. Mean (SD) amniotic fluid oxalate concentration was 19.0 (4.3) mumols/l. PMID:2031609

  18. [Basic mechanisms: absorption and excretion of cholesterol and other sterols].

    PubMed

    Cofan Pujol, Montserrat

    2014-01-01

    Cholesterol is of vital importance for vertebrate cell membrane structure and function. It is obvious that adequate regulation of cholesterol homeostasis is essential. Hypercholesterolemia promotes atherosclerosis and thereby represents a major risk factor for cardiovascular disease. The liver has been considered the major site of control in maintenance of cholesterol homeostasis. The liver facilitates clearance of (very) low density lipoprotein particles and cholesterol-containing chylomicron remnants, synthesizes cholesterol, synthesizes and secretes (nascent) high density lipoprotein particles, secretes cholesterol and bile salts to bile, and is involved in reverse cholesterol transport. In recent years, however, the importance of the intestine in many aspects of cholesterol physiology is increasingly recognized. It has become apparent that direct secretion of cholesterol from the blood compartment into the intestine, or transintestinal cholesterol excretion, plays a major role in disposal of cholesterol via the feces. This review will discuss current knowledge on the physiology of cholesterol homeostasis, with emphasis on cholesterol absorption, cholesterol synthesis and fecal excretion, and therapeutic options for hypercholesterolemia.

  19. High Salt Diet Affects Renal Sodium Excretion and ERRα Expression.

    PubMed

    Wang, Dan; Wang, Yang; Liu, Fu-Qiang; Yuan, Zu-Yi; Mu, Jian-Jun

    2016-01-01

    Kidneys regulate the balance of water and sodium and therefore are related to blood pressure. It is unclear whether estrogen-related receptor α (ERRα), an orphan nuclear receptor and transcription factor highly expressed in kidneys, affects the reabsorption of water and sodium. The aim of this study was to determine whether changes in the expressions of ERRα, Na⁺/K⁺-ATPase and epithelial sodium channel (ENaC) proteins affected the reabsorption of water and sodium in kidneys of Dahl salt-sensitive (DS) rats. SS.13BN rats, 98% homologous to the DS rats, were used as a normotensive control group. The 24 h urinary sodium excretion of the DS and SS.13BN rats increased after the 6-week high salt diet intervention, while sodium excretion was increased in DS rats with daidzein (agonist of ERRα) treatment. ERRα expression was decreased, while β- and γ-ENaC mRNA expressions were increased upon high sodium diet treatment in the DS rats. In the chromatin immunoprecipitation (CHIP) assay, positive PCR signals were obtained in samples treated with anti-ERRα antibody. The transcriptional activity of ERRα was decreased upon high salt diet intervention. ERRα reduced the expressions of β- and γ-ENaC by binding to the ENaC promoter, thereby increased Na+ reabsorption. Therefore, ERRα might be one of the factors causing salt-sensitive hypertension. PMID:27043552

  20. Metabolism and Excretion of Trichloroethylene after Inhalation by Human Subjects

    PubMed Central

    Bartoníček, V.

    1962-01-01

    Eight volunteers were exposed to trichloroethylene vapour (1,042 μg./l.) for five hours; 51 to 64% of the inhaled trichloroethylene was retained. The concentration of trichloroethanol and trichloroacetic acid in the urine was studied daily for a three-week period; on the third day both metabolites were determined in faeces, sweat, and saliva. The concentration of trichloroacetic acid in plasma and red blood cells was studied on alternate days. Of the trichloroethylene retained, 38·0 to 49·7% was excreted in the urine as trichloroethanol and 27·4 to 35·7% as trichloroacetic acid. Of both metabolites 8·4% was excreted in the faeces. Sweat collected on the third day of the experiment contained 0·10 to 1·92 mg./100 ml. trichloroethanol and 0·15 to 0·35 mg./100 ml. trichloroacetic acid. In saliva the concentrations were 0·09 to 0·32 mg./100 ml. trichloroethanol and 0·10 to 0·15 mg./100 ml. trichloroacetic acid. The value of the expression trichloroethanol/trichloroacetic acid calculated in the urine within 22 days was within the range 1·15 to 1·81. PMID:13865497

  1. Influence of curcumin on cyclosporin-induced reduction of biliary bilirubin and cholesterol excretion and on biliary excretion of cyclosporin and its metabolites.

    PubMed

    Deters, M; Siegers, C; Hänsel, W; Schneider, K P; Hennighausen, G

    2000-06-01

    We investigated the ability of curcumin, which can be extracted from different Curcuma species, to prevent cyclosporin-induced reduction of biliary bilirubin and cholesterol excretion, and its influence on biliary excretion of cyclosporin (CS) and its metabolites in the bile fistula model in rats. I.v. injection of curcumin (25 and 50 mg/kg) after 30 min increased dose-dependently basal bile flow (30 microliters/kg/min) up to 200%, biliary bilirubin excretion (3000 pmol/kg/min) up to 150%, and biliary cholesterol excretion (22 nmol/kg/min) up to 113%. CS (30 mg/kg) reduced bile flow to 66% and biliary excretion of bilirubin and of cholesterol to 33% of the basal value 30 min after i.v. injection. I.v. administration of curcumin (25 and 50 mg/kg) 30 min after CS increased bile flow dose dependently again to 130% for 1 hour and biliary excretion of cholesterol and of bilirubin to 100% of the basal value for 30 and 150 min, respectively. Injection of curcumin 15 min before CS prevented the CS-induced drop of bile flow at 50 mg/kg and reduction of biliary bilirubin excretion already at 25 mg/kg until the end of the experiment (180 min). The CS-induced reduction of biliary cholesterol excretion, however, was not prevented by curcumin. Finally, the biliary excretions of CS (1200 ng/kg/min) and its metabolites (1200 ng/kg/min) were slightly reduced by curcumin at a dose of 50 mg/kg (to 83% of the initial values). The clinical importance of these controversial effects remains to be shown.

  2. I-131 rose bengal excretion test is not dead

    SciTech Connect

    Antico, V.F.; Denhartog, P.; Ash, J.M.; Gilday, D.L.; Houle, S.

    1985-03-01

    One hundred and thirty I-131 Rose Bengal Excretion Studies (RBI) were performed on 84 patients over nine years. In 90% (56/60) of cases with biliary atresia, the 72-hour RBI was less than or equal to 7%. In only 12.5% (3/24) of cases with neonatal hepatitis was the 72-hour RBI less than or equal to 7%. The accuracy of the test was 91% with a specificity of 88%. Thirty patients later were studied following a Kasai procedure. The RBI test reliably predicted the patency of the anastomosis. The authors conclude that the 72-hour RBI is a reliable test in the diagnosis of biliary atresia and in the documentation of biliary patency following surgery, provided adequate care is taken in stool collection and measurement.

  3. Excretion of artifactual endogenous digitalis-like factors

    SciTech Connect

    Kelly, R.A.

    1986-07-01

    Radioimmunoassays have been used to detect digoxin-like immunoreactive factors (DLF) in the plasma and urine of hypertensive patients and rats with deoxycorticosterone acetate (DOCA)-salt hypertension. DLF, partially purified from DOCA-HS urine by antidigoxin antibody immunoaffinity chromatography, was found to have a molecular weight <2000. When DOCA-HS rats were switched to the low-sodium chow, DLF excretion dropped precipitously. No measurable DLF was detected in the plasma of rats eating either chow. However, >95% of the urinary DLF could be attributed to a contaminant in the standard laboratory chow. These data document the importance of excluding nonspecific compounds and exogenous sources of DLF when sensitive radioligand and biologic assays are used to detect endogenous inhibitors of the sodium pump.

  4. Serum protein adsorption and excretion pathways of metal nanoparticles

    PubMed Central

    Vinluan, Rodrigo D; Zheng, Jie

    2015-01-01

    While the synthesis of metal nanoparticles (NPs) with fascinating optical and electronic properties have progressed dramatically and their potential biomedical applications were also well demonstrated in the past decade, translation of metal NPs into the clinical practice still remains a challenge due to their severe accumulation in the body. Herein, we give a brief review on size-dependent material properties of metal NPs and their potential biomedical applications, followed by a summary of how structural parameters such as size, shape and charge influence their interactions with serum protein adsorption, cellular uptake and excretion pathways. Finally, the future challenges in minimizing serum protein adsorption and expediting clinical translation of metal NPs were also discussed. PMID:26377047

  5. Urinary excretion of parabens in pregnant Japanese women.

    PubMed

    Shirai, Sayaka; Suzuki, Yayoi; Yoshinaga, Jun; Shiraishi, Hiroaki; Mizumoto, Yoshifumi

    2013-01-01

    Urinary excretion of free and total (free plus conjugated) forms of methyl, ethyl, n-propyl and n-butyl parabens (MP, EP, PP and BP, respectively) and their metabolite p-hydroxybenzoic acid were measured for 111 pregnant Japanese women. Frequent detection of parabens and their metabolite indicated that exposure takes place daily for pregnant Japanese women. The estrogenic potency of PP was 20 times higher than those of the other 3 parabens for the present subjects when both abundance in the urine and the relative estrogenic activity of each compound was considered. Detection of free parabens suggested dermal exposure, probably from their inclusion in personal care products. No statistical association was found between the anogenital index (birth weight-adjusted AGD) of male offspring and the concentrations of any parabens in the urine of the mothers suggesting that the parabens were not apparently estrogenically active at the exposure level of the present subjects.

  6. Alkali absorption and citrate excretion in calcium nephrolithiasis

    NASA Technical Reports Server (NTRS)

    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).

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

    PubMed Central

    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

  8. Increased Salivary Nitrite and Nitrate Excretion in Rats with Cirrhosis.

    PubMed

    Mahmoodi, Somayeh; Rahmatollahi, Mahdieh; Shahsavari, Fatemeh; Shafaroodi, Hamed; Grayesh-Nejad, Siyavash; Dehpour, Ahmad R

    2015-11-01

    Increased nitric oxide (NO) formation is mechanistically linked to pathophysiology of the extrahepatic complications of cirrhosis. NO is formed by either enzymatic or non-enzymatic pathways. Enzymatic production is catalyzed by NO synthase (NOS) while entero-salivary circulation of nitrate and nitrite is linked to non-enzymatic formation of NO under acidic pH in the stomach. There is no data on salivary excretion of nitrate and nitrite in cirrhosis. This study was aimed to investigate salivary levels of nitrate and nitrite in a rat model of biliary cirrhosis. Cirrhosis was induced by bile duct ligation (BDL). Four weeks after the operation, submandibular ducts of anesthetized BDL and control rats were cannulated with polyethylene microtube for saliva collection. Assessment of pH, nitrite and nitrate levels was performed in our research. We also investigated NOS expression by real time RT-PCR to estimate eNOS, nNOS and iNOS mRNA levels in the submandibular glands. Salivary pH was significantly lower in BDL rats in comparison to control animals. We also observed a statistically significant increase in salivary levels of nitrite as well as nitrate in BDL rats while there was no elevation in the mRNA expression of nNOS, eNOS, and iNOS in submandibular glands of cirrhotic groups. This indicates that an increased salivary level of nitrite/nitrate is less likely to be linked to increased enzymatic production of NO in the salivary epithelium. It appears that nitrate/nitrite can be transported from the blood stream by submandibular glands and excreted into saliva as entero-salivary circulation, and this mechanism may have been exaggerated during cirrhosis. PMID:26786986

  9. Stereoselectivity of biliary excretion of 2-arylpropionates in rats.

    PubMed

    Menzel, S; Beck, W S; Brune, K; Geisslinger, G

    1993-01-01

    To examine the stereoselectivity of biliary excretion, the optically pure enanatiomers of ketoprofen (KT), ibuprofen (IBU), and flurbiprofen (FLU) were intravenously administered to normal and bile duct-cannulated rats at 10 mg/kg. The recovery of total KT in bile was significantly higher after administration of (S)-KT than after (R)-KT [90.1 +/- 3.5% vs 68.8 +/- 8.2%, n = 3, P < 0.05]. In normal rats the terminal half-life of (R)-KT was significantly shorter than that of (S)-KT after administration of (R)-KT (2.2 +/- 0.6 h vs 14.3 +/- 4.9 h, n = 3, P < 0.05). The terminal half-life of both enantiomers was significantly shorter in rats with continuous bile drainage as compared to normal rats. No significant differences in pharmacokinetic parameters could be found between both enantiomers in bile duct-cannulated animals. The total amount of IBU in bile was slightly higher after administration of (S)-IBU than after (R)-IBU administration. The percentage of (R)-IBU after (R)-IBU administration, however, was very low [(R)-IBU: 1.5 +/- 0.9%, (S)-IBU: 23.4 +/- 5.8%]. In normal rats the clearance of (R)-IBU was significantly higher as compared to (S)-IBU. Differences in pharmacokinetic parameters between normal and bile duct-cannulated rats were not statistically significant due to high interindividual variability. The total recovery of FLU, which was excreted in bile to a lower extent than either KT or IBU, also tended to be greater after S-enantiomer administration. Only small amounts of (S)-FLU could be recovered in bile after (R)-FLU administration.(ABSTRACT TRUNCATED AT 250 WORDS)

  10. Relationship between endogenous 3-methylhistidine excretion and body composition.

    PubMed

    Lukaski, H C; Mendez, J; Buskirk, E R; Cohn, S H

    1981-03-01

    Fourteen healthy men (aged 20-30 yr) consumed two isocaloric, isonitrogenous diets in the sequence of a 4-day meat diet (MD) followed by a 7-day meal-free diet (MFD). Urinary 3-methylhistidine (3MH) excretion during the MD (513 +/- 21 mumol . day-1, mean +/- SE) was significantly higher (P less than 0.01) than day 3 of the MFD (230 +/- 10 mumol . day-1), after which the mean daily 3MH output was constant with a mean coefficient of variation of 4.5%. There was no change in fat-free body mass (FFBM) determined by densitometry at the start (62.3 +/- 1.8 kg) and the end (62.2 +/- 1.9 kg) of the 11-day dietary period. Mean muscle mass (MM) calculated from measurements of total-body potassium and nitrogen was 23.4 +/- 1.3 kg. Endogenous 3MH excretion was related more closely to MM (r = 0.91, P less than 0.001) than to FFBM measured by densitometry (r = 0.81, P less than 0.001). Only a low correlation coefficient (r = 0.33, P less than 0.05) was observed between 3MH and the nonmuscle component of FFBM. Urinary creatinine output also was correlated significantly with 3MH (r = 0.87; P less than 0.001) and MM (r = 0.79; P less than 0.01). It is concluded that because endogenous 3MH is significantly related to MM in man, it can be used as a marker to study in vivo total-body muscle protein degradation provided that the necessary dietary restrictions are observed.

  11. Multidrug resistance p-glycoprotein 2 is essential for the biliary excretion of indocyanine green.

    PubMed

    Huang, L; Vore, M

    2001-05-01

    Multidrug resistance P-glycoprotein 2 (Mdr2) is a phospholipid translocator in the canalicular membrane that is essential for the formation of biliary phospholipid vesicles and mixed lipid/bile salt micelles. Incorporation into biliary vesicles and micelles is thought to contribute to the hepatobiliary excretion of certain hydrophobic organic anions, such as indocyanine green (ICG). The present studies characterized the biliary excretion of two hydrophobic organic anions, ICG and estradiol-17beta(beta-D-glucuronide) (E(2)17G), in the single-pass isolated perfused liver and the biliary excretion of glutathione (GSH) in vivo in wild-type and Mdr2-/- female mice. The biliary excretion of ICG (0.4 micromol) was reduced by 90%, while the biliary excretion of total GSH was decreased by 65% in Mdr2-/- mice relative to wild-type mice. In contrast, the biliary excretion of E(2)17G (0.1 micromol) was increased by 30% in Mdr2-/- mice. These data indicate that the absence of Mdr2 differentially influences the biliary excretion of these organic anions and suggest that phospholipid vesicles and mixed micelles in bile are essential for the biliary excretion of ICG.

  12. Urinary excretion of arsenicals following daily intake of various seafoods during a two weeks intervention.

    PubMed

    Molin, M; Ulven, S M; Dahl, L; Goessler, W; Fliegel, D; Holck, M; Sloth, J J; Oshaug, A; Alexander, J; Meltzer, H M; Ydersbond, T A

    2014-04-01

    The excretion pattern of arsenic (As) species after seafood intake varies widely depending on species ingested and individual handling. We have previously reported the 72 h urinary excretion of arsenicals following a single dose of seafood. Here, we report the excretion patterns in the same 37 subjects following 15 days daily consumption of either 150 g cod, salmon, blue mussels or potato (control), followed by a 72 h period with a low-As diet. In all seafood groups, total As (tAs) in plasma and urinary excretion of tAs, arsenobetaine (AB) and dimethylarsinate (DMA) increased significantly after 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 303 μg in the cod, blue mussel and salmon groups, respectively; about twice the amounts after the single dose study indicating accumulation of arsenicals. In the cod group, rapid excretion after the single dose was associated with lower total As in blood and less accumulation after two weeks with seafood indicating lower accumulation. In the blue mussels group only, inorganic As (iAs) excretion increased significantly, whilst methylarsonate (MA) strongly increased, indicating a possible toxicological concern of repeated mussel consumption. PMID:24468672

  13. Renal excretion in coho salmon (Oncorhynchus kisutch) after acute exposure to 3-trifluoromethyl-4-nitrophenol

    USGS Publications Warehouse

    Hunn, J.B.; Allen, J.L.

    1975-01-01

    COHO SALMON (ONCORHYNCHUS KISUTCH) EXPOSED TO AN ACUTE, SUBLETHAL CONCENTRATION OF 3-TRIFLUOROMETHLY 1-4 NITROPHENOL (TFM) EXHIBITED AN INCREASED OUTPUT OF URINE WHEN COMPARED WITH CONTROLS, BUT THE URINARY EXCRETION OF NA, K, CA, MG AND C1 WAS NOT AFFECTED. ABOUT 35 TIMES MORE CONJUGATED TFM THAN FREE TFM WAS EXCRETED DURING THE 24-HOUR STUDY PERIOD.

  14. Biological monitoring of dichloropropene: Air concentrations, urinary metabolite, and renal enzyme excretion

    SciTech Connect

    Osterloh, J.D.; Wang, R.; Schneider, F.; Maddy, K. )

    1989-07-01

    Fifteen applicators of dichloropropene (DCP) were studied for personal air exposure to DCP, excretion of the metabolite of DCP (3CNAC), and excretion of the renal tubular enzyme, N-acetyl glucosaminidase (NAG). Each was studied for four 6-8 h consecutive intervals following baseline determinations of 3CNAC and NAG excretion. In accord with pilot data, 24-h urinary excretion of 3CNAC (mg) correlated well with exposure product for DCP (min exposed.mg/m{sup 3}), r = 0.854, p less than .001. A more precise correlation of the air exposure product with urinary excretion of 3CNAC was discerned by using the morning urine after the previous day of exposure (micrograms/mg of creatinine), r = 0.914, p less than .001. Four workers had clinically elevated activity of NAG (greater than 4 mU/mg creatinine) in any of their urine collections after baseline. Nine workers showed greater than 25% increases in NAG excretion when compared to baseline. Dichloropropene air exposure products of greater than 700 mg.min/m{sup 3} or excretion of greater than 1.5 mg 3CNAC/d distinguished abnormally high daily excretion of NAG. These data demonstrate a firm positive relationship between air exposure and internal exposure, and a possible subclinical nephrotoxic effect in DCP workers.

  15. Excretion of pyridinium crosslinks correlates with disease activity and appendicular bone loss in early rheumatoid arthritis.

    PubMed Central

    Gough, A K; Peel, N F; Eastell, R; Holder, R L; Lilley, J; Emery, P

    1994-01-01

    OBJECTIVE--To establish if urinary excretion rates of the collagen crosslinks pyridinoline and deoxypyridinoline, which are known to be elevated in established rheumatoid arthritis (RA), are useful markers of bone loss in this disease. METHODS--Eight hour urine collections on all patients and 52 controls were performed, and the rates of pyridinoline and deoxypyridinoline excretion were measured. Bone mineral density (BMD), by dual energy x-ray absorption, and full laboratory and clinical assessments were performed. RESULTS--The rates of excretion of pyridinoline and deoxypyridinoline were significantly increased in patients compared with controls (p < 0.001). Pyridinoline excretion was associated with increased disease activity (ESR/CRP) but not disability (HAQ score/Functional Grade), and correlated with BMD loss at the femoral neck (p < 0.01). CONCLUSION--The excretion of collagen crosslinks may be useful as markers of bone and cartilage turnover in patients with RA. PMID:8311548

  16. Excretion of the dipeptidyl peptidase-4 inhibitor linagliptin in rats is primarily by biliary excretion and P-gp-mediated efflux.

    PubMed

    Fuchs, Holger; Runge, Frank; Held, Heinz-Dieter

    2012-04-11

    Linagliptin is a selective, competitive dipeptidyl peptidase-4 (DPP-4) inhibitor, recently approved in the USA, Japan and Europe for the treatment of type 2 diabetes. It has non-linear pharmacokinetics and, unlike other DPP-4 inhibitors, a largely non-renal excretion route. It was hypothesised that P-glycoprotein (P-gp)-mediated intestinal transport could influence linagliptin bioavailability, and might contribute to its elimination. Two studies evaluated the role of P-gp-mediated transport in the bioavailability and intestinal secretion of linagliptin in rats. In the bioavailability study, male Wistar rats received single oral doses of linagliptin, 1 or 15 mg/kg, plus either the P-gp inhibitor, zosuquidar trihydrochloride, or vehicle. For the intestinal secretion study, rats underwent bile duct cannulation, and urine, faeces, and bile were collected. At the end of the study, gut content was sampled. Inhibition of intestinal P-gp increased the bioavailability of orally administered linagliptin, indicating that this transport system plays a role in limiting the uptake of linagliptin from the intestine. This effect was dependent on linagliptin dose, and could play a role in its non-linear pharmacokinetics after oral dosing. Systemically available linagliptin was mainly excreted unchanged via bile (49% of i.v. dose), but some (12%) was also excreted directly into the gut independently of biliary excretion. Thus, direct excretion of linagliptin into the gut may be an alternative excretion route in the presence of liver and renal impairment. The primarily non-renal route of excretion is likely to be of benefit to patients with type 2 diabetes, who have a high prevalence of renal insufficiency.

  17. Renal excretion of intravenously infused amoxycillin and ampicillin.

    PubMed Central

    Sjövall, J; Westerlund, D; Alván, G

    1985-01-01

    The aim of this study was to determine whether concentration-dependent renal clearance of ampicillin and amoxycillin occurs. The drugs were given as single 20 min i.v. infusions in doses ranging from 1.9 to 2.8 g to nine healthy volunteers using a cross-over design. Plasma and urinary concentrations were determined by a selective liquid chromatographic method using frequent sampling up to 10 and 30 h respectively after termination of the infusion. The renal clearance of the drugs was independent of the plasma concentration. The mean (s.d.) renal clearances of ampicillin and amoxycillin were 167 (24) and 157 (20) ml min-1 1.73 m-2 respectively. The net secretion was about 50% of the total renal clearance of both drugs. The plasma concentration and urinary excretion rate versus time curves indicated a polyexponential decline, which could be described by both a biexponential and a triexponential equation. The former proved to be more reliable, especially in the calculation of micro rate constants. There was a tendency to more sustained plasma concentrations after amoxycillin, also illustrated by a significantly lower mean (s.d.) plasma clearance of this drug, viz. 185 (30) ml min-1 1.73 m-2, as compared to ampicillin, 210 (24) ml min-1 1.73 m-2 (P less than 0.04). There were no major differences in the disposition rate constants and the distribution volumes of ampicillin and amoxycillin. The mean (s.d.) plasma half-life was 1.7 (0.3) h for both drugs. The urinary excretion rate indicated a slower terminal disposition rate however, with ampicillin and amoxycillin half-lives of 3.4 (2.0) and 3.9 (1.2) h respectively. The longer half-life in the terminal phase may be due to increased tubular reabsorption at low urinary concentrations. It was not possible to determine in this study whether the half-life was affected by changes in clearance or volume of distribution. The urinary solubility of the drugs was dependent on pH. This could explain the massive macroscopic

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

    PubMed

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

    2016-03-01

    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 bioavailability. 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

  19. Absorption and excretion of organic compounds of copper by sheep.

    PubMed

    Mahmoud, O M; Ford, E J

    1983-10-01

    When sheep are injected subcutaneously with copper calcium edetate or copper oxyquinoline sulphonate there is a rapid increase in the concentration of copper in whole blood, serum and urine within the first 24 h. When sheep are injected with copper methionate the concentration of copper in whole blood and serum rises slowly over a period of about 10 days and there is no detectable increase in urinary copper. After the injection of each of the three compounds, there was a steady increase in the caeruloplasmin activity in serum over a period of 10 to 20 days, followed by a slow fall to pre-injection activity by 40 days. There was a marked increase in the beta-globulin fraction of serum 9 days after the injection of copper methionate but not after the other 2 compounds and the amounts of 2 copper containing proteins in liver were greater 60 days after the injection of copper methionate than after the injection of the other two compounds. The copper content of the 3 organic compounds is absorbed and excreted at different rates by sheep. The amounts of copper-containing protein produced in the liver also differ according to the organic component of the compound injected. The results suggest that the lower toxicity of copper injected as methionate compared with that injected as copper calcium edetate or copper oxyquinoline sulphonate is due to the slower absorption and transport of the copper to the liver and kidney.

  20. Net acid excretion during first week of life.

    PubMed

    Chan, L L; Balfe, J W; Exeni, R; Cifuentes, R F; Bryan, M H; Atkinson, S A

    1981-03-01

    Metabolic acidosis occurs frequently in newborns. Net acid excretion (NAE) in 34 preterm and 12 term infants was measured during the first week of life. Twenty preterm infants received breast milk or formula; the remaining infants received total parenteral nutrition (TPN) -- synthetic amino acids or casein hydrolysate solution. NAE for breast milk vs formula fed infants was 5.4 +/- 0.4 and 7.8 +/- 0.6 muEq/min/m2 (mean +/- SEM). The corresponding values for the two TPN solutions in preterm infants were significantly higher at 12.5 +/- 1.4 and 19.4 +/- 3.5 muEq/min/m2. Term infants produced even greater amount of net acid, 20.6 +/- 2.9 and 35 +/- 3.7 muEq/min/m2 respectively for the two TPN solutions. Milk fed infants are less prone to acidosis because of base generated from milk consumption. Due to its inherent acidogenic effect, TPN solutions induce acidosis more readily. Infants receiving TPN are therefore required to generate a higher NAE rate to maintain acid-base homeostasis compared to milk fed infants.

  1. Excretion of Transmissible Spongiform Encephalopathy Infectivity in Urine

    PubMed Central

    Gregori, Luisa; Kovacs, Gabor G.; Alexeeva, Irina; Budka, Herbert

    2008-01-01

    The route of transmission of most naturally acquired transmissible spongiform encephalopathy (TSE) infections remains speculative. To investigate urine as a potential source of TSE exposure, we used a sensitive method for detection and quantitation of TSE infectivity. Pooled urine collected from 22 hamsters showing clinical signs of 263K scrapie contained 3.8 ± 0.9 infectious doses/mL of infectivity. Titration of homogenates of kidneys and urinary bladders from the same animals gave concentrations 20,000-fold greater. Histologic and immunohistochemical examination of these same tissues showed no indications of inflammatory or other pathologic changes except for occasional deposits of disease-associated prion protein in kidneys. Although the source of TSE infectivity in urine remains unresolved, these results establish that TSE infectivity is excreted in urine and may thereby play a role in the horizontal transmission of natural TSEs. The results also indicate potential risk for TSE transmission from human urine–derived hormones and other medicines. PMID:18760007

  2. Reduction of urinary uric acid excretion in patients with proteinuria.

    PubMed

    Zou, Huiqing; Xiang, Mingfeng; Ye, Xinming; Xiong, Yuanzhen; Xie, Baogang; Shao, Jianghua

    2015-12-01

    Serum uric acid (UA) concentration is positively associated with proteinuria. However, the relationship between proteinuria and urinary metabolites of purine metabolism remains unknown. This study developed a hydrophilic interaction chromatography (HILIC)-based HPLC method with ultraviolet detection (UV) to quantify creatinine (Cr), UA, xanthine, and hypoxanthine in human urine simultaneously. The urinary concentrations of UA and Cr obtained by our method are consistent with those measured by an autoanalyzer. The HPLC-HILIC-UV method was validated as selective and robust with simple sample preparation for measuring UA, xanthine, hypoxanthine and Cr, which is suitable for large clinical studies. The UA/Cr ratios in random urine samples were 5.5 times lower in proteinuria patients (0.077±0.008) than in healthy individuals (0.424±0.037). Moreover, the UA/hypoxanthine ratio in proteinuria patients was approximately 10 times lower than that in healthy individuals. Our findings revealed a reduced urinary UA excretion, which is one of the factors leading to increased serum UA in proteinuria patients.

  3. Assessment of urinary iodine excretion among normal Kuwaiti adults.

    PubMed

    Al-Yatama, Fatma I; Al-Bader, Maie D; Al-Mazidi, Zaidan M; Ali, Ameena; Al-Omair, Ali S; Al-Jehma, Nasser A; Mohammed, Fawziah

    2009-12-01

    This study was performed to investigate the status of iodine intake among the Kuwaiti population and its effect on thyroid function. The study group was comprised of 139 females and 86 males with a mean age of 33 and 35 years, respectively. Urinary iodine excretion (UIE) and serum free T4 (FT4), thyrotropin hormone (TSH), antiperoxidase antibodies (anti- TPOAb), and antithyroglobulin antibodies (anti-TGAb) were determined. Median UIE was 148 μg/L (within the recommended level by the World Health Organization [WHO]). However, UIE levels of <100 and <50 μg/L were detected in both male and female groups, respectively. Serum levels of TSH and FT4 were normal for all except one of the participants who suffered from hyperthyroidism, possibly as a result of elevated iodine intake, which was reflected in an increased UIE of 590 μg/L. Elevated anti-TPOAb >75 IU/mL and anti-TGAb >150 IU/mL were detected in 15% and 34% of subjects; only 10% of them had elevated levels of both anti-TPOAb and anti-TGAb. Thus, based on the WHO recommendations, the iodine intake for the Kuwaiti population is adequate. However, it is recommended that a national study be conducted by the appropriate authority in order to eliminate any artifacts which may have appeared in this study.

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

    PubMed

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

    2016-03-01

    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 bioavailability. 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.

  5. Variation of ²¹⁰Po daily urinary excretion for male subjects at environmental level.

    PubMed

    Hölgye, Z; Hýža, M; Mihalík, J; Rulík, P; Škrkal, J

    2015-05-01

    (210)Po was determined in 24-h urine of seven healthy males from Prague, Czech Republic, for ten consecutive days. The results show that for each volunteer, the urinary excretion of (210)Po changed only little from day to day in the studied time period. For two volunteers, the difference in the daily excreted (210)Po activity for two consecutive days was not significant, given the 95% confidence interval (two sigma) of the activity measurements. The same is valid for the excretion data of the other volunteers, except for some days where the differences were slightly higher. The range of daily urinary excretion of (210)Po of each volunteer in the studied time period was quite narrow. Among the volunteers, the maximum daily urinary excretion value of (210)Po was at most about a factor of 2.5 higher than the lowest excretion value. An attempt to explain the observed small inter-individual variability of (210)Po excretion in daily urine is made.

  6. Variation of ²¹⁰Po daily urinary excretion for male subjects at environmental level.

    PubMed

    Hölgye, Z; Hýža, M; Mihalík, J; Rulík, P; Škrkal, J

    2015-05-01

    (210)Po was determined in 24-h urine of seven healthy males from Prague, Czech Republic, for ten consecutive days. The results show that for each volunteer, the urinary excretion of (210)Po changed only little from day to day in the studied time period. For two volunteers, the difference in the daily excreted (210)Po activity for two consecutive days was not significant, given the 95% confidence interval (two sigma) of the activity measurements. The same is valid for the excretion data of the other volunteers, except for some days where the differences were slightly higher. The range of daily urinary excretion of (210)Po of each volunteer in the studied time period was quite narrow. Among the volunteers, the maximum daily urinary excretion value of (210)Po was at most about a factor of 2.5 higher than the lowest excretion value. An attempt to explain the observed small inter-individual variability of (210)Po excretion in daily urine is made. PMID:25712002

  7. Excretion of laccase by sycamore (Acer pseudoplatanus L.) cells. Effects of a copper deficiency.

    PubMed

    Bligny, R; Gaillard, J; Douce, R

    1986-07-15

    Copper-deprived sycamore (Acer pseudoplatanus) cells do not excrete molecules of active laccase in their culture medium. In the range of 2-100 micrograms of copper initially present per litre of nutrient solution, the total laccase activity measured in the cell suspensions at the end of the exponential phase of growth was closely proportional to the amount of added copper. However, copper-deprived cells excreted the laccase apoprotein (laccase without copper) at the same rate as copper-supplied cells excreted the active, copper-containing, laccase. When the culture medium was initially supplied with limiting amounts of copper, the active laccase was excreted until all copper molecules were metabolized. Thereafter, the laccase apoprotein was excreted. Consequently, at the end of the exponential phase of growth, the cell supernatants contained a mixture of apoprotein and copper-containing laccase. After purification and concentration, this mixture of copper-containing laccase (blue) and laccase apoprotein (slightly yellow) showed a yellow-green colour. Under copper-limiting culture conditions an equivalent decrease of Type 1, Type 2 and Type 3 Cu2+ was observed. Addition of copper to copper-deficient enzyme solutions does not result in a recovery of the enzyme activity. However, when added to copper-deficient sycamore-cell suspensions, copper induced a recovery of the excretion of active enzyme, at a normal rate, within about 10 h. The first molecules of active laccase were excreted after 3-4 h.

  8. The effect of ethanol on the urinary excretion and differential metabolism of folate compounds

    SciTech Connect

    Eisenga, B.H.

    1989-01-01

    In rats chronically fed ethanol and folate-containing diets for 12 weeks, urinary folate excretion was increased. However, no significant tissue depletion was noted unless rats were fed folate deficient diets. In rats fed folate-deficient diets urinary folate excretion was dramatically decreased at two weeks, when tissue folate stores were replete. After 16 weeks of diet treatment, the urinary excretion of an intraperitoneal dose of {sup 3}H-PteGlu was not altered in folate-deficient rats. Although acute ethanol administration (oral or intravenous) increased endogenous folate excretion that of {sup 3}H-PteGlu was not significantly altered, nor was the fractional excretion of {sup 3}H-label. To clarify this effect, the metabolism of {sup 3}H-PteGlu was studied. HPLC analysis of urine showed extensive metabolism of {sup 3}H-PteGlu to other folate substrates. Oral ethanol-treatment increased the fractional excretion of endogenous 5-CH{sub 3}-H{sub 4}PteGlu with no increase in urinary excretion or fractional excretion of other {sup 3}H-labeled derivatives. After infusion of tritium labeled 5-CH{sub 3}-H{sub 4}PteGlu, ethanol treatment increased the fractional excretion of endogenous and {sup 3}H-5-CH{sub 3}-H{sub 4}PteGlu, but not that of other folates. There was rapid uptake of {sup 3}H-label by the kidney with only 10% of the urinary {sup 3}H-label as {sup 3}H-5-CH{sub 3}-H{sub 4}PteGlu.

  9. Depletion of hepatic uridine diphosphoglucuronic acid decreases the biliary excretion of drugs.

    PubMed

    Gregus, Z; Watkins, J B; Thompson, T N; Klaassen, C D

    1983-05-01

    Hepatic levels of uridine diphosphoglucuronic acid (UDPGA) in rats decreased substantially (greater than 80%) 40 min after galactosamine (GAL) (600 mg/kg i.p.) or after 1 hr of diethyl ether (DE) narcosis. Biliary excretion of several cholephils requiring glucuronidation before excretion was reduced by GAL 76, 62, 92, 90 and 97% for bilirubin, diethylstilbestrol, iopanoic acid, phenolphthalein and valproic acid, respectively. GAL treatment caused delayed plasma clearances of the parent compounds and reductions in plasma concentrations and biliary excretions of glucuronide conjugates. The degree of this reduction was related to the maximal excretion rate of the individual compounds. For phenolphthalein glucuronide and phenol-3,6-dibromphthalein disulfonate, which do not undergo conjugation, GAL had no effect on their biliary excretion. DE-induced UDPGA depletion had no effect on phenolphthalein glucuronide excretion but reduced that of phenol-3,6-dibromphthalein disulfonate 25%. DE did not affect the plasma elimination or biliary secretion of phenolphthalein. Of the other cholephils requiring conjugation, DE reduced the excretion of bilirubin, diethylstilbestrol, iopanoic acid and valproic acid by 41, 29, 76 and 28%, respectively. DE decreased the plasma elimination of the parent compounds and the appearance of the conjugates in both plasma and bile. Reduction of glucuronide excretion into bile was less pronounced at higher doses of the cholephilic anions. Neither treatment reduced in vitro hepatic UDP-glucuronosyltransferase activity toward these substrates or substantially altered extrahepatic UDPGA concentrations. Thus, both GAL and DE decreased UDPGA to similar concentrations, but the biliary excretion of compounds requiring glucuronidation before secretion was depressed to a greater extent by GAL.

  10. Intercomparison of two cavity ring-down spectroscopy analyzers for atmospheric 13CO2 / 12CO2 measurement

    NASA Astrophysics Data System (ADS)

    Pang, Jiaping; Wen, Xuefa; Sun, Xiaomin; Huang, Kuan

    2016-08-01

    Isotope ratio infrared spectroscopy (IRIS) permits continuous in situ measurement of CO2 isotopic composition under ambient conditions. Previous studies have mainly focused on single IRIS instrument performance; few studies have considered the comparability among different IRIS instruments. In this study, we carried out laboratory and ambient measurements using two Picarro CO2δ13C analyzers (G1101-i and G2201-i (newer version)) and evaluated their performance and comparability. The best precision was 0.08-0.15 ‰ for G1101-i and 0.01-0.04 ‰ for G2201-i. The dependence of δ13C on CO2 concentration was 0.46 ‰ per 100 ppm and 0.09 ‰ per 100 ppm, the instrument drift ranged from 0.92-1.09 ‰ and 0.19-0.37 ‰, and the sensitivity of δ13C to the water vapor mixing ratio was 1.01 ‰ / % H2O and 0.09 ‰ / % H2O for G1101-i and G2201-i, respectively. The accuracy after correction by the two-point mixing ratio gain and offset calibration method ranged from -0.04-0.09 ‰ for G1101-i and -0.13-0.03 ‰ for G2201-i. The sensitivity of δ13C to the water vapor mixing ratio improved from 1.01 ‰ / % H2O before the upgrade of G1101-i (G1101-i-original) to 0.15 ‰ / % H2O after the upgrade of G1101-i (G1101-i-upgraded). Atmospheric δ13C measured by G1101-i and G2201-i captured the rapid changes in atmospheric δ13C signals on hourly to diurnal cycle scales, with a difference of 0.07 ± 0.24 ‰ between G1101-i-original and G2201-i and 0.05 ± 0.30 ‰ between G1101-i-upgraded and G2201-i. A significant linear correlation was observed between the δ13C difference of G1101-i-original and G2201-i and the water vapor concentration, but there was no significant correlation between the δ13C difference of G1101-i-upgraded and G2201-i and the water vapor concentration. The difference in the Keeling intercept values decreased from 1.24 ‰ between G1101-i-original and G2201-i to 0.36 ‰ between G1101-i-upgraded and G2201-i, which indicates the importance of consistency among different IRIS instruments.

  11. Infant botulism with prolonged faecal excretion of botulinum neurotoxin and Clostridium botulinum for 7 months.

    PubMed

    Derman, Y; Korkeala, H; Salo, E; Lönnqvist, T; Saxen, H; Lindström, M

    2014-02-01

    In Finland in April 2010, a 3-month old baby was diagnosed with type A infant botulism. He excreted botulinum neurotoxin and/or Clostridium botulinum in his faeces until November 2010. Five months of excretion was after clinical recovery and discharge from hospital. C. botulinum isolates recovered from the household dust in the patient's home were genetically identical to those found in the infant's stool samples. Long-term faecal excretion of C. botulinum may pose a possible health risk for the parents and others in close contact with the infant.

  12. Felinine excretion in domestic cat breeds: a preliminary investigation.

    PubMed

    Hagen-Plantinga, E A; Bosch, G; Hendriks, W H

    2014-06-01

    The aim of this study was to determine possible differences in felinine excretion between domesticated cat breeds. For this purpose, urine was collected from a total of 83 privately owned entire male cats from eight different breeds in the Netherlands during the period of November 2010 till November 2011. In the collected samples, free felinine and creatinine concentrations were measured. Free felinine concentrations were expressed relative to the urinary creatinine concentration to compensate for possible variations in renal output. The mean (±SD) felinine:creatinine (Fel:Cr) ratio as measured over all cats was 0.702 (±0.265). Both the Abyssinian and Sphynx breeds showed the highest Fel:Cr ratio (0.878 ± 0.162 and 0.878 ± 0.341 respectively) which significantly differed from the ratios of the British Shorthairs (0.584 ± 0.220), Birmans (0.614 ± 0.266), Norwegian Forest cats (0.566 ± 0.296) and Siberian cats (0.627 ± 0.124). The Fel:Cr ratios of the Persians (0.792 ± 0.284) and Ragdolls (0.673 ± 0.256) showed no statistical difference with either of the other breeds. A significant proportion of the observed variation between the different feline breeds could be explained by hair growth, as both hair growth and felinine production compete for available cysteine. Shorthaired and hairless cat breeds generally showed a higher Fel:Cr ratio compared to longhaired cat breeds, with the exception of Persian cats. Further research is warranted to more closely study the effect of hair growth on felinine production. PMID:23819478

  13. Urinary excretion of 1-pyrenol in automotive repair workers.

    PubMed

    Granella, M; Clonfero, E

    1993-01-01

    The urinary excretion of a pyrene metabolite was evaluated in 65 automotive repair workers whose skin was exposed to used mineral oils, and in 41 controls. Pyrene contents were determined in oily material taken from cloths used to clean various types of engines (n = 8) and were found to vary (mean +/- SD) from 2.8 +/- 0.4 ppm for dirty matter obtained from diesel truck engines to 9.3 +/- 8.2 ppm for that from petrol car engines. Tobacco smoking and polycyclic aromatic hydrocarbon (PAH)-rich diets were considered as confounding factors. At both the beginning and the end of the working week, the values of urinary 1-pyrenol were slightly higher in exposed subjects (0.178 +/- 0.150 and 0.194 +/- 0.135 mumol/mol creatinine on Monday and Friday, respectively) than in controls (0.124 +/- 0.090 mumol/mol creatinine) (Mann-Whitney test, z = 2.741, P < 0.01). The urinary 1-pyrenol values were higher in both smoking and non-smoking subjects than in controls. The highest values were found in urinary samples of smokers exposed to used mineral oils (0.259 +/- 0.201 mumol/mol creatinine). In non-smoking workers (n = 40), post-shift 1-pyrenol values were 0.154 +/- 0.105 mumol/mol creatinine, as against 0.083 +/- 0.042 mumol/mol creatinine for the 19 non-smoking controls (Mann-Whitney test, z = 2.765, P < 0.01). In automobile repair workers, urinary 1-pyrenol values before the beginning of the weekly workshift did not differ substantially from those measured at the end of the week, not being related to the subjective degree of dirty skin as stated by workers.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8144234

  14. Absorption, distribution, metabolism, and excretion of isoflavonoids after soy intake.

    PubMed

    Franke, Adrian A; Lai, Jennifer F; Halm, Brunhild M

    2014-10-01

    Soy is the major source of dietary exposure to isoflavonoids (IFLs). Accumulating evidence supports a role for soy and IFLs in the protection against many chronic diseases including cancer. After soy intake we found a biphasic IFL appearance pattern in plasma as well as in urine that we suggest to be due to IFL absorption in the small intestine (ca. 10%) during the first 2h after intake and IFL absorption in the large intestine (ca. 90%) 4-6 h after intake. While each IFL disappears from the circulation at different times excellent correlations between urinary and circulating IFL values were discovered and algorithms to convert urinary excretion values into circulating levels were established. We suggest the term 'apparent bioavailability' when using urinary data to describe IFL exposure. The IFL bioavailability was found to be influenced by gut bacteria, oral antibiotic treatment (OABX), and an individual's age and health status. While daidzein (DE) and genistein start to be absorbed minutes after intake, equol (EQ) appears in plasma only after a minimum of 8h following soy intake owing to the required transit time of DE to the colon where the conversion of DE to EQ takes place by intestinal microbiota. We have also shown that the apparent IFL bioavailability is higher in children than adults, higher in healthy versus non-healthy individuals, and decreased in children but increased in adults during OABX. Finally, we propose to use a urinary EQ/DE ratio of 0.018 with a DE threshold to identify EQ producers. With this cutoff definition we observed that EQ production is inconsistent over time in 5-30% of both premenopausal and postmenopausal women.

  15. Avosentan Reduces Albumin Excretion in Diabetics with Macroalbuminuria

    PubMed Central

    Wenzel, René R.; Littke, Thomas; Kuranoff, Susan; Jürgens, Christiane; Bruck, Heike; Ritz, Eberhard; Philipp, Thomas; Mitchell, Anna

    2009-01-01

    Despite the first-line use of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs), there is still a large need to improve the prevention and progression of diabetic nephropathy and its associated cardiovascular events. Endothelin antagonists have shown anti-inflammatory, antifibrotic, and antiproteinuric effects in experimental studies. This study was a randomized, placebo-controlled, double-blind, parallel-design, dosage-range study of the effect of the endothelin-A antagonist avosentan (SPP301) on urinary albumin excretion rate (UAER) in patients with diabetic nephropathy. We randomly assigned 286 patients with diabetic nephropathy, macroalbuminuria (UAER 0.2 to 5.6 mg/min), and BP <180/110 mmHg to 12 wk of avosentan (5, 10, 25, and 50 mg) or placebo, in addition to standard ACEI/ARB therapy. Relative to baseline, all avosentan dosages decreased mean relative UAER (−16.3 to −29.9%) compared with placebo (35.5%). Median relative UAER decreased with all avosentan dosages (−28.7 to −44.8%) compared with placebo (12.1%). Creatinine clearance and BP were unchanged at 12 wk. The main adverse events were peripheral edema (12%), mainly with high (≥25 mg) dosages of avosentan; significant increases in liver enzymes did not occur. Twenty-one (7.3%) patients experienced adverse events that led to withdrawal from study medication. In summary, the endothelin-A antagonist avosentan given in addition to standard ACEI/ARB treatment decreases UAER in patients with diabetic nephropathy and macroalbuminuria. PMID:19144760

  16. Biliary excretion of foreign compounds. Benzene and its derivatives in the rat

    PubMed Central

    Abou-El-Makarem, M. M.; Millburn, P.; Smith, R. L.; Williams, R. T.

    1967-01-01

    1. The extent of the excretion in the bile of the rat of benzene and 21 of its simple derivatives was studied. 2. Some 16 compounds of molecular weight less than 200, and including neutral molecules (benzene and toluene), aromatic acids, aromatic amines and phenols, were injected in solution intraperitoneally into biliary-cannulated rats. Metabolites in the bile were identified and estimated. The extent of biliary excretion of these compounds was low, i.e. 0–10% of the dose in 24hr., and most appeared in the bile mainly as conjugates. 3. The biliary excretion of six conjugates of molecular weight less than 300, including three glycine conjugates, one sulphate conjugate, one glucuronic acid conjugate and two acetyl derivatives, was low (less than 3% of the dose). 4. It is concluded that simple benzene derivatives of molecular weight less than about 300 are poorly excreted in rat bile. PMID:16742555

  17. Specific IgA Enhances the Transcytosis and Excretion of Hepatitis A Virus

    PubMed Central

    Counihan, Natalie A.; Anderson, David A.

    2016-01-01

    Hepatitis A virus (HAV) replicates in the liver, and is excreted from the body in feces. However, the mechanisms of HAV transport from hepatocytes to the gastrointestinal tract are poorly understood, mainly due to lack of suitable in vitro models. Here, we use a polarized hepatic cell line and in vivo models to demonstrate vectorial transport of HAV from hepatocytes into bile via the apical cell membrane. Although this transport is specific for HAV, the rate of fecal excretion in inefficient, accounting for less than 1% of input virus from the bloodstream per hour. However, we also found that the rate of HAV excretion was enhanced in the presence of HAV-specific IgA. Using mice lacking the polymeric IgA receptor (pIgR−/−), we show that a proportion of HAV:IgA complexes are transported via the pIgR demonstrating a role for specific antibody in pathogen excretion. PMID:26911447

  18. ENVIRONMENTAL FOOTPRINT OF PHARMACEUTICALS - THE SIGNIFICANCE OF FACTORS BEYOND DIRECT EXCRETION TO SEWERS

    EPA Science Inventory

    The combined excretion of active pharmaceutical ingredients (APIs) via urine and feces is considered the primary route by which APIs from human pharmaceuticals enter the environment. Disposal of unwanted, leftover medications by flushing into sewers has been considered a secondar...

  19. Evidence that auxin-induced growth of soybean hypocotyls involves proton excretion

    SciTech Connect

    Rayle, D.L.; 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.

  20. Action of steroids on H+ and NH+4 excretion in the toad urinary bladder.

    PubMed

    Frazier, L W; Zachariah, N Y

    1979-09-14

    This study was done to determine if steroid compounds will stimulate the urinary bladder of the toad to increase its capacity to acidify the urine and excrete NH+4. Aldosterone, 17 beta-estradiol, dexamethasone, pregnenolone, and cholesterol were tested on the bladder. All compounds tested were found to stimulate the rate of acidification by the bladder, above that of a paired control hemibladder. In contrast, only the steroids aldosterone and 17 beta-estradiol were found to stimulate NH+4 excretion in the bladder. Cycloheximide was found to block the action of aldosterone on the NH+4 excretion, but did not have a significant effect on the stimulation of acidification by aldosterone. We conclude that steroids stimulate H+ and NH+4 excretion in the toad urinary bladder. In addition, the NH+4 excretory system seems to be more specific to this effect than is the H+ excretory system. PMID:113550

  1. Grazing and excretion by zooplankton in the Peru upwelling system during April 1977

    NASA Astrophysics Data System (ADS)

    Dagg, M.; Cowles, T.; Whitledge, T.; Smith, S.; Howe, S.; Judkins, D.

    1980-01-01

    Rates of ingestion and excretion by adult females of the copepods Calanus chilensis, Eucalanus inermis, and Centropages brachiatus were measured in natural seawater during a cruise in the Peru upwelling system during April 1977. Simultaneously, zooplankton samples were collected for later determination of the abundance and distribution of these and other species. For these three organisms, feeding, and excretion rates of individuals are combined with information on the animal concentrations to estimate the grazing stress on the phytoplankton at each station, and to estimate the excretory nitrogen produced at each station. Comparison of grazing stresses with measured rates of primary production indicates that these large copepods were harvesting less than 5% of the daily phytoplankton production. Comparison of the nitrogen excretion rates with the amounts of excreted nitrogen in the water column indicates that less than 3% of the ambient excretory nitrogen was produced daily by these copepods. The importance of the abundant small zooplankton in the system is suggested.

  2. Interactions among lead, cadmium, and arsenic in relation to porphyrin excretion patterns.

    PubMed Central

    Fowler, B A; Mahaffey, K R

    1978-01-01

    This paper reviews the effects of lead (Pb), cadmium (Cd), and arsenic (As) on the mitrochondrion with emphasis on alteration of mitochondrial heme biosynthetic pathway. The information was used to examine results of a Pb x Cd x As interaction study which employed urinary porphyrin excretion patterns as one assessment criterion. Data from the study showed that dietary Pb produced increased urinary excretion of aminolevulinic acid (ALA) and coproporphyrin. Dietary exposure to organic or inorganic As caused increased excretion of uroporphyrin and to a lesser extent coproporphyrin, while dietary Cd caused no significant changes in urinary levels of any of the porphyrins measured. The combination of Pb plus As produced an additive effect on coproporphyrin excretion but not that of either ALA or uroporphyrin. These data are discussed in relation to utilization of urinary porphyrins for assessing toxicity and elemental interactions. PMID:720307

  3. Interindividual differences in circadian patterns of catecholamine excretion, body temperature, performance, and subjective arousal.

    PubMed

    Akerstedt, T; Fröberg, J E

    1976-12-01

    Interindividual differences in circadian rhythms of urinary catecholamine excretion, performance, self-ratings of arousal and oral temperature were studied in 80 subjects divided into three groups--morning-active, evening-active, and intermediate. Catecholamine excretion, body temperature, and self-ratings of arousal exhibited pronounced circadian variations. Morning-active subjects exceeded other groups in the 24 h level of adrenaline excretion but crest phases did not differ, occurring close to 13.00 h. No differences between groups were found for noradrenaline excretion. Crest phases occurred close to noon. Self-rated alertness exhibited a significantly earlier (14.12 h) crest phase for morning-active than for evening-active subjects (16.09 h). The performance did not differ between groups.

  4. Influence of frequent and long-term consumption of legume seeds on excretion of intestinal gases.

    PubMed

    O'Donnell, A U; Fleming, S E

    1984-07-01

    The objective of this study was to determine the influence of long-term and frequent consumption of legume seeds on the excretion of fermentation gases. This was done by comparing gas excretion for one group (B) of individuals that habitually consumed legumes to that of another group (NB) of individuals that only infrequently consumed legumes. Gas excretion was measured during one diet period (control) when they consumed their normal diets and during one diet period (bean) when they consumed 100 g (dry weight), daily, of red kidney beans. Twelve men participated in this study on an outpatient basis and received each diet for 23 days. We found that there was neither short-term (no difference throughout the 23 days) nor long-term (NB and B groups were equivalent) adaptation in the quantity of gas that was excreted. However, both groups subjectively expressed greater tolerance and less physical discomfort as the bean-consuming period continued. PMID:6430062

  5. Associations of ambulatory blood pressure with urinary caffeine and caffeine metabolite excretions.

    PubMed

    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

  6. Associations of ambulatory blood pressure with urinary caffeine and caffeine metabolite excretions.

    PubMed

    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.

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

    PubMed Central

    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 with a Na+ concentration of up to 10 mM appears to be optimal for the health of male Japanese Papilio butterflies. The molar ratio of K+ to Na+ observed in leaves was 43.94 and that observed in flower nectars was 10.93. The Na+ amount in 100 g of host plant leaves ranged from 2.11 to 16.40 mg, and the amount in 100 g of flower nectar ranged from 1.24 to 108.21 mg. Differences in host plants did not explain the differences in the frequency of puddling observed for different Japanese Papilio species. The amounts of Na+, K+, Ca2+, and Mg2+ in the meconium of both male and female butterflies were also measured, and both males and females excreted more K+ than the other three ions. Thus, the fluid that was excreted by butterflies at emergence also had a role in the excretion of the excessive K+ in their bodies. The quantities of Na+ and K+ observed in butterfly eggs were approximately 0.50 μg and 4.15 μg, respectively; thus, female butterflies required more K+ than male butterflies. Therefore, female butterflies did not puddle to excrete K+. In conclusion, the purpose of puddling for male Papilio butterflies is not only to absorb Na+ to correct deficiencies but also to excrete excessive K+. PMID:25955856

  8. The effects of unsaturated dietary fats on absorption, excretion, synthesis, and distribution of cholesterol in man

    PubMed Central

    Grundy, Scott M.; Ahrens, E. H.

    1970-01-01

    Cholesterol balance studies were carried out in 11 patients with various types of hyperlipoproteinemia to determine the mechanism by which unsaturated fats lower plasma cholesterol. Unsaturated fats produced no increase in fecal endogenous neutral steroids in 10 of 11 patients and no decrease in absorption of exogenous cholesterol in 5 patients who received cholesterol in the diet. In 8 of 11 patients no changes occurred in excretion of bile acids during the period on unsaturated fat when plasma cholesterol was declining. However, in 3 of 11 patients small but significant increases in bile acid excretion were found during this transitional period; in 2 others increases also occurred after plasma cholesterol had become constant at lower levels on unsaturated fat. Since the majority of patients showed no change in cholesterol or bile acid excretions during the transitional period, we propose that when excretion changes did occur they were probably not the cause of the plasma cholesterol change. Furthermore, turnover data and specific activity curves suggested that cholesterol synthesis was not influenced by exchange of dietary fats. Thus, excluding changes in excretion and synthesis, we conclude that it is most likely that unsaturated fats cause plasma cholesterol to be redistributed into tissue pools. We have also examined the possibility that cholesterol which is redistributed into tissues could be secondarily excreted as neutral steroids or bile acids. In at least 5 of 11 patients excretion patterns were consistent with this explanation. However, we cannot rule out that excretion changes may have been due to alterations in transit time, to changes in bacterial flora, or to transitory changes in absorption or synthesis of cholesterol or bile acids. Our conclusion that unsaturated fats cause a redistribution of cholesterol between plasma and tissue pools points to the necessity in future to explore where cholesterol is stored, to what extent stored cholesterol can

  9. K+ excretion: the other purpose for puddling behavior in Japanese Papilio butterflies.

    PubMed

    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 with a Na+ concentration of up to 10 mM appears to be optimal for the health of male Japanese Papilio butterflies. The molar ratio of K+ to Na+ observed in leaves was 43.94 and that observed in flower nectars was 10.93. The Na+ amount in 100 g of host plant leaves ranged from 2.11 to 16.40 mg, and the amount in 100 g of flower nectar ranged from 1.24 to 108.21 mg. Differences in host plants did not explain the differences in the frequency of puddling observed for different Japanese Papilio species. The amounts of Na+, K+, Ca2+, and Mg2+ in the meconium of both male and female butterflies were also measured, and both males and females excreted more K+ than the other three ions. Thus, the fluid that was excreted by butterflies at emergence also had a role in the excretion of the excessive K+ in their bodies. The quantities of Na+ and K+ observed in butterfly eggs were approximately 0.50 μg and 4.15 μg, respectively; thus, female butterflies required more K+ than male butterflies. Therefore, female butterflies did not puddle to excrete K+. In conclusion, the purpose of puddling for male Papilio butterflies is not only to absorb Na+ to correct deficiencies but also to excrete excessive K+.

  10. Behavioral and Perceived Stressor Effects on Urinary Catecholamine Excretion in Adult Samoans

    PubMed Central

    Bergey, Meredith R.; Steele, Matthew S.; Bereiter, David A.; Viali, Satupaitea; McGarvey, Stephen T.

    2011-01-01

    Objectives The effects of perceptions and behaviors related to culturally-patterned socioeconomic obligations on catecholamine excretion rates were studied in a cross-sectional sample of Samoan adults. Methods 378 participants, ages 29-62 years, from 9 villages throughout Samoa, provided timed overnight urine specimens, and self-reported perceptions and behaviors associated with contributions to one's family, aiga, and chief, matai, and communal gift exchanges, fa'alavelave. Urinary norepinephrine and epinephrine excretion rates were measured by high performance liquid chromatography with electrochemical detection. Age (≤40 vs. >40 years) and gender-specific regression models were estimated to detect associations with catecholamine excretion. Results Young women who contribute more to their matai, who consider fa'alavelave to be a financial strain, and who view their contribution to their matai to be ‘just right’, had significantly higher residence-adjusted norepinephrine excretion. Young women who contribute more to their matai, who consider fa'alavelave to be a financial strain, and who consider their contribution to their aiga not to be a burden, had higher epinephrine excretion. Older men who contribute more to their aiga and who perceive their contribution to their aiga to be ‘just right’ had increased residence-adjusted epinephrine excretion. Conclusions Individual-level perceptions and behaviors related to traditional socioeconomic obligations are a significant correlate of increased overnight catecholamine excretion rates. Higher excretion rates may be attributed to psychosocial stress arousal associated with a discordance between personal desires for upward social mobility, and family and community-based socioeconomic obligations. Changes in patterns of individual-level psychosocial stress arousal may contribute to cardiovascular disease risk in modernizing Samoans. PMID:21793091

  11. K+ excretion: the other purpose for puddling behavior in Japanese Papilio butterflies.

    PubMed

    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 with a Na+ concentration of up to 10 mM appears to be optimal for the health of male Japanese Papilio butterflies. The molar ratio of K+ to Na+ observed in leaves was 43.94 and that observed in flower nectars was 10.93. The Na+ amount in 100 g of host plant leaves ranged from 2.11 to 16.40 mg, and the amount in 100 g of flower nectar ranged from 1.24 to 108.21 mg. Differences in host plants did not explain the differences in the frequency of puddling observed for different Japanese Papilio species. The amounts of Na+, K+, Ca2+, and Mg2+ in the meconium of both male and female butterflies were also measured, and both males and females excreted more K+ than the other three ions. Thus, the fluid that was excreted by butterflies at emergence also had a role in the excretion of the excessive K+ in their bodies. The quantities of Na+ and K+ observed in butterfly eggs were approximately 0.50 μg and 4.15 μg, respectively; thus, female butterflies required more K+ than male butterflies. Therefore, female butterflies did not puddle to excrete K+. In conclusion, the purpose of puddling for male Papilio butterflies is not only to absorb Na+ to correct deficiencies but also to excrete excessive K+. PMID:25955856

  12. Drug elimination function of rat small intestine: metabolism and intraluminal excretion.

    PubMed

    Yasuhara, M; Kurosaki, Y; Kimura, T; Sezaki, H

    1984-10-15

    The metabolic and excretory function of the small intestine was investigated after oral and intravenous administration of drugs having an aromatic amino group to rats. After administration of drugs into the intestinal loop at the initial concentration of 0.1 mM, significant excretion of their N-acetylated forms into the lumen was observed. The amount of N-acetyl forms excreted in the lumen were 39.3 +/- 3.5, 63.5 +/- 20.9 and 18.0 +/- 13.8% of disappeared drugs from the lumen for p-aminobenzoic acid (PABA), p-aminosalicylic acid and sulfanilic acid, respectively. The excretion of p-acetamidobenzoic acid (Ac-PABA) after the absorption of PABA was reduced by the coadministration with salicylic acid, benzoic acid and 2,4-dinitrophenol. Salicylic acid noncompetitively inhibited the acetylation of PABA by the intestinal N-acetyltransferase. A good correlation was found between the intestinal N-acetyltransferase activities for drugs and the intraluminal excretion of N-acetyl derivatives after intestinal absorption of drugs. These results indicate that a drug having a higher susceptibility to intestinal N-acetyltransferase would undergo a greater excretion into the lumen in its N-acetyl form after intestinal absorption. After intravenous administration of PABA at a dose of 100 mumole/kg, 4.02 +/- 0.51% of dose was excreted in the lumen as Ac-PABA in 30 min. On the other hand, a significantly smaller fraction (2.72 +/- 0.68% of dose) was excreted in the lumen after intravenous injection of 100 mumole/kg of Ac-PABA. The larger excretion of Ac-PABA after administration of PABA indicates the contribution of intestinal metabolism on the transfer of PABA not only after oral, but also after intravenous administration.

  13. Excretion rates of 210Po and 210Pb in Prague inhabitants.

    PubMed

    Hölgye, Zoltán

    2013-01-01

    Excretion rates of (210)Po and (210)Pb in the urine were investigated in 40 healthy inhabitants of Prague (22 males, 18 females, age: 23-70 y, non-smokers). In 20 inhabitants the excretion rates of (210)Po and (210)Pb in faeces were also studied. The mean urinary excretion rates of (210)Po and (210)Pb were 4.1 and 6.0 mBq d(-1), respectively. It was demonstrated, statistically, that the urinary excretion rates of (210)Po and (210)Pb are higher in men than those in women. The highest excretion rates of (210)Po and (210)Pb found in the participants were 10.8 and 16.6 mBq d(-1), respectively. The mean activity ratio of (210)Po/(210)Pb in the urine was 0.73. The mean excretion rates of (210)Po and (210)Pb in faeces were 56.5 and 54.6 mBq d(-1). The mean activity ratio of (210)Po/(210)Pb in faeces was 1.0.

  14. Oxalobacter sp. reduces urinary oxalate excretion by promoting enteric oxalate secretion.

    PubMed

    Hatch, M; Cornelius, J; Allison, M; Sidhu, H; Peck, A; Freel, R W

    2006-02-01

    The primary goal of this study was to test the hypothesis that Oxalobacter colonization alters colonic oxalate transport thereby reducing urinary oxalate excretion. In addition, we examined the effects of intraluminal calcium on Oxalobacter colonization and tested the hypothesis that endogenously derived colonic oxalate could be degraded by lyophilized Oxalobacter enzymes targeted to this segment of the alimentary tract. Oxalate fluxes were measured across short-circuited, in vitro preparations of proximal and distal colon removed from Sprague-Dawley rats and placed in Ussing chambers. For these studies, rats were colonized with Oxalobacter either artificially or naturally, and urinary oxalate, creatinine and calcium excretions were determined. Colonized rats placed on various dietary treatment regimens were used to evaluate the impact of calcium on Oxalobacter colonization and whether exogenous or endogenous oxalate influenced colonization. Hyperoxaluric rats with some degree of renal insufficiency were also used to determine the effects of administering encapsulated Oxalobacter lysate on colonic oxalate transport and urinary oxalate excretion. We conclude that in addition to its intraluminal oxalate-degrading capacity, Oxalobacter interacts physiologically with colonic mucosa by inducing enteric oxalate secretion/excretion leading to reduced urinary excretion. Whether Oxalobacter, or products of Oxalobacter, can therapeutically reduce urinary oxalate excretion and influence stone disease warrants further investigation in long-term studies in various patient populations. PMID:16518326

  15. Skin contamination, airborne concentrations, and urinary metabolite excretion of propoxur during harvesting of flowers in greenhouses.

    PubMed

    Brouwer, R; van Maarleveld, K; Ravensberg, L; Meuling, W; de Kort, W; van Hemmen, J J

    1993-11-01

    In eight greenhouses used for carnation culture, workers engaged in harvesting (n = 16), were monitored for dermal and respiratory exposure and urinary excretion of propoxur. Dermal exposure of hands and forearms was estimated from dislodgable foliar residue, using a transfer factor (a measure of transfer of pesticides from leaves to the skin) and the total number of working hours. Total estimated dermal and respiratory exposure during harvesting ranged from 0.2 to 46 mg and from 3 to 278 micrograms, respectively. To study the relationship between external and internal exposure to propoxur, respiratory and dermal exposure levels were compared with the total amount of 2-isopropoxyphenol (IPP), the major metabolite of propoxur, excreted in urine in 24 hr. The Pearson correlation coefficient between dermal exposure and the total amount of excreted IPP was 0.95. A correlation coefficient of 0.84 was found between respiratory exposure and the amount of IPP excreted. The latter association was probably caused by the covariation of respiratory and dermal exposure levels (r = 0.85). Assuming negligible oral absorption, calculations indicated that dermal exposure could account for > 80% of the amount of excreted IPP. On the basis of the amount of IPP excreted, there was no reason to suspect increased health risks for workers from exposure to propoxur during harvesting.

  16. Creatinine adjustment of spot urine samples and 24 h excretion of iodine, selenium, perchlorate, and thiocyanate.

    PubMed

    Ohira, Shin-ichi; Kirk, Andrea B; Dyke, Jason V; Dasgupta, Purnendu K

    2008-12-15

    Creatinine (CR) adjustment is widely used for the estimation of urinary 24 h excretion from spot urine samples. We have compared CR-adjusted values for urinary iodine, selenium, perchlorate, and thiocyanate to measured 24 h excretion. The urine samples were collected from a cohort of 14 breastfeeding mothers with both spot samples and 24 h collection, 52 24 h and spot sample pairs where the 24 h CR value fell within the "normal" adult female CR excretion range of 0.6-1.6 g/day were considered for this analysis. In addition, a nonlactating female and a male subject provided all micturitions for 1 and 5 days, respectively. Creatinine was analyzed with a Jáffe reaction-based automated analyzer. Iodine and selenium were determined with induction coupled plasma-mass spectrometry (ICP-MS). Perchlorate and thiocyanate were measured with ion chromatography (IC)-isotope dilution tandem mass spectrometry (MS/MS). Creatinine-adjusted values were poor substitutes of the actual 24 h excretion values (average deviation +/-69, 78, 105, and 104% for iodine, selenium, perchlorate, and thiocyanate, respectively.). Over a 5 day period, the 24 h iodine excretion predicted based on creatinine adjustment of spot samples for the same individual deviated between -83.5 to +101% from the actual measured value, the minimum absolute error being 2.5%. Creatinine adjustment for estimation of 24 h excretion from spot samples was not effective for iodine, selenium, perchlorate, or thiocyanate.

  17. Daily variations in urinary excretion of luteinizing hormone and follicle stimulating hormone in idiopathic isosexual precocity.

    PubMed

    Penny, R; Olambiwonnu, N O; Frasier, S D

    1977-01-01

    The 24-hour urinary excretion of luteinizing hormone (LH) and follicle stimulating hormone (FSH) was determined for 30 days in an 8.3-year-old girl with isosexual precocity and for 25 days in a normal 11.9-year-old girl. The pattern of daily variation in urinary LH and FSH excretion observed in the girl with sexual precocity was similar to that of the normal menstrual cycle. The LH and FSH midcycle peaks were 132.5 IU/24 hours and 26.3 IU/24 hours, respectively. Excluding the midcycle peak, the daily excretion of LH was 28.4 +/- 9.3 (SD) IU/24 hours, and the excretion of FSH was 8.9 +/- 1.9 (SD) IU/24 hours, values comparable to those of normal adult females. In contrast, the daily excretion of LH in the normal 11.9-year-old girl was 6.9 +/- 1.1 (SD) IU/24 hours and FSH excretion was 3.9 +/- 0.9 (SD) IU/24 hours. No LH or FSH surge was observed. The data are consistent with early maturation of the hypothalamic-pituitary-gonadal axis in idiopathic isosexual precocity.

  18. Urea and Ammonia Metabolism and the Control of Renal Nitrogen Excretion.

    PubMed

    Weiner, I David; Mitch, William E; Sands, Jeff M

    2015-08-01

    Renal nitrogen metabolism primarily involves urea and ammonia metabolism, and is essential to normal health. Urea is the largest circulating pool of nitrogen, excluding nitrogen in circulating proteins, and its production changes in parallel to the degradation of dietary and endogenous proteins. In addition to serving as a way to excrete nitrogen, urea transport, mediated through specific urea transport proteins, mediates a central role in the urine concentrating mechanism. Renal ammonia excretion, although often considered only in the context of acid-base homeostasis, accounts for approximately 10% of total renal nitrogen excretion under basal conditions, but can increase substantially in a variety of clinical conditions. Because renal ammonia metabolism requires intrarenal ammoniagenesis from glutamine, changes in factors regulating renal ammonia metabolism can have important effects on glutamine in addition to nitrogen balance. This review covers aspects of protein metabolism and the control of the two major molecules involved in renal nitrogen excretion: urea and ammonia. Both urea and ammonia transport can be altered by glucocorticoids and hypokalemia, two conditions that also affect protein metabolism. Clinical conditions associated with altered urine concentrating ability or water homeostasis can result in changes in urea excretion and urea transporters. Clinical conditions associated with altered ammonia excretion can have important effects on nitrogen balance.

  19. Correlation of urinary nickel excretion with observed 'total' and inhalable aerosol exposures of nickel refinery workers.

    PubMed

    Werner, M A; Thomassen, Y; Hetland, S; Norseth, T; Berge, S R; Vincent, J H

    1999-12-01

    An investigation of the relationship between observed nickel aerosol exposures and urinary nickel excretion was undertaken at a Scandinavian nickel refinery. The goal of the study was to assess the impact of nickel aerosol speciation, the use of particle size-selective sampling instrumentation and adjustment of urinary levels for creatinine excretion on the usefulness of urinary nickel excretion as a marker for exposure. Urinary nickel measurements and paired 'total' and inhalable aerosol exposure measurements were collected each day for one week from refinery workers in four process areas. The mean observed urinary nickel concentration was 12 micrograms L-1 (11 micrograms of Ni per g of creatinine). The strongest relationships between urinary excretion and aerosol exposure were found when urinary nickel levels were adjusted for creatinine excretion and when exposure to only soluble forms of nickel aerosol was considered. No significant difference was observed between measures of 'total' and inhalable aerosol in the ability to predict urinary excretion patterns. In the light of these results, it is recommended that consideration be given to the chemical species distribution of nickel aerosol in the use of urinary nickel measurements as a screening tool for cancer risk in occupationally-exposed populations. PMID:11529189

  20. Diel variation in ammonia excretion, glutamine levels, and hydration status in two species of terrestrial isopods.

    PubMed

    Wright, Jonathan C; Peña-Peralta, Mariasol

    2005-01-01

    Terrestrial isopods (suborder Oniscidea) excrete most nitrogen diurnally as volatile ammonia, and ammonia-loaded animals accumulate nonessential amino acids, which may constitute the major nocturnal nitrogen pool. This study explored the relationship between ammonia excretion, glutamine storage/mobilization, and water balance, in two sympatric species Ligidium lapetum (section Diplocheta), a hygric species; and Armadillidium vulgare (Section Crinocheta), a xeric species capable of water-vapor absorption (WVA). Ammonia excretion (12-h), tissue glutamine levels, and water contents were measured following field collection of animals at dusk and dawn. In both species, diurnal ammonia excretion exceeded nocturnal excretion four- to fivefold while glutamine levels increased four- to sevenfold during the night. Most glutamine was accumulated in the somatic tissues ("body wall"). While data support the role of glutamine in nocturnal nitrogen storage, potential nitrogen mobilization from glutamine breakdown (162 micromol g(-1) in A. vulgare) exceeds measured ammonia excretion (2.5 micromol g(-1)) over 60-fold. This may serve to generate the high hemolymph ammonia concentrations (and high P(NH3)) seen during volatilization. The energetic cost of ammonia volatilization is discussed in the light of these findings. Mean water contents were similar at dusk and dawn in both species, indicating that diel cycles of water depletion and replenishment were not occurring. PMID:15578188

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

    PubMed Central

    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

  2. Twenty-four hour urinary excretion of vitamins, minerals and nitrogen by Eskimos.

    PubMed

    Ellestad-Sayed, J; Hildes, J A; Schaefer, O; Lobban, M C

    1975-12-01

    In 1971-1972, urines were collected over 24 hours from ambulatory Iglooligmiut who ranged in age from 6 to 76 years. Collections were made every 3-4 months over a calendar year. The mean of each individual's two to four collections was used as the best estimate of that person's average daily excretion for nitrogen, thiamin, riboflavin, N'-methylnicotinamide, calcium, phosphorus, and magnesium. The excretion of the three B vitamins by all age groups was high when compared with interpretive standards. Urea nitrogen comprised 80-90% of total nitrogen excreted by all age groups. Twenty-four-hour mineral excretions did not differ with age and sex group except that adult men excreted significantly more phosphorus. Urinary urea nitrogen and phosphorus were linearly related, suggesting that they have a common source; namely, meat. Winter was generally the season of lowest excretion of the nutrients assayed. Since these nutrients are available from imported foods, particularly during the winter, it would appear that even in the winter the Iglooligmiut are more dependent on hunting and fishing for sources of these nutrients than on the well-stocked commercial grocery outlets. PMID:803002

  3. Reliability of Urinary Excretion Rate Adjustment in Measurements of Hippuric Acid in Urine

    PubMed Central

    Nicolli, Annamaria; Chiara, Federica; Gambalunga, Alberto; Carrieri, Mariella; Bartolucci, Giovanni Battista; Trevisan, Andrea

    2014-01-01

    The urinary excretion rate is calculated based on short-term, defined time sample collections with a known sample mass, and this measurement can be used to remove the variability in urine concentrations due to urine dilution. Adjustment to the urinary excretion rate of hippuric acid was evaluated in 31 healthy volunteers (14 males and 17 females). Urine was collected as short-term or spot samples and tested for specific gravity, creatinine and hippuric acid. Hippuric acid values were unadjusted or adjusted to measurements of specific gravity, creatinine or urinary excretion rate. Hippuric acid levels were partially independent of urinary volume and urinary flow rate, in contrast to specific gravity and creatinine, which were both highly dependent on the hippuric acid level. Accordingly, hippuric acid was independent on urinary specific gravity and creatinine excretion. Unadjusted and adjusted values for specific gravity or creatinine were generally closely correlated, especially in spot samples. Values adjusted to the urinary excretion rate appeared well correlated to those unadjusted and adjusted to specific gravity or creatinine values. Thus, adjustment of crude hippuric acid values to the urinary excretion rate is a valid procedure but is difficult to apply in the field of occupational medicine and does not improve the information derived from values determined in spot urine samples, either unadjusted or adjusted to specific gravity and creatinine. PMID:25019265

  4. Diel variation in ammonia excretion, glutamine levels, and hydration status in two species of terrestrial isopods.

    PubMed

    Wright, Jonathan C; Peña-Peralta, Mariasol

    2005-01-01

    Terrestrial isopods (suborder Oniscidea) excrete most nitrogen diurnally as volatile ammonia, and ammonia-loaded animals accumulate nonessential amino acids, which may constitute the major nocturnal nitrogen pool. This study explored the relationship between ammonia excretion, glutamine storage/mobilization, and water balance, in two sympatric species Ligidium lapetum (section Diplocheta), a hygric species; and Armadillidium vulgare (Section Crinocheta), a xeric species capable of water-vapor absorption (WVA). Ammonia excretion (12-h), tissue glutamine levels, and water contents were measured following field collection of animals at dusk and dawn. In both species, diurnal ammonia excretion exceeded nocturnal excretion four- to fivefold while glutamine levels increased four- to sevenfold during the night. Most glutamine was accumulated in the somatic tissues ("body wall"). While data support the role of glutamine in nocturnal nitrogen storage, potential nitrogen mobilization from glutamine breakdown (162 micromol g(-1) in A. vulgare) exceeds measured ammonia excretion (2.5 micromol g(-1)) over 60-fold. This may serve to generate the high hemolymph ammonia concentrations (and high P(NH3)) seen during volatilization. The energetic cost of ammonia volatilization is discussed in the light of these findings. Mean water contents were similar at dusk and dawn in both species, indicating that diel cycles of water depletion and replenishment were not occurring.

  5. RELEASE OF INTROGENOUS SUBSTANCES BY BREWER'S YEAST. 3. SHOCK EXCRETION OF AMINO ACIDS.

    PubMed

    LEWIS, M J; PHAFF, H J

    1964-06-01

    Lewis, M. J. (University of California, Davis), and H. J. Phaff. Release of nitrogenous substances by brewers' yeast. III. Shock excretion of amino acids. J. Bacteriol. 87:1389-1396. 1964.-When Saccharomyces carlsbergensis (two strains) and S. cerevisiae (one strain) were grown in static culture and the harvested, washed cells were suspended in a solution of glucose, amino acids were suddenly released and then rapidly reabsorbed in a space of about 2 hr. The phenomenon of amino acid release, which was termed shock excretion, varied in intensity with the strain of yeast and was shown to be dependent on the size of the pool of free amino acids within the cells. Shock excretion was independent of osmotic pressure of the suspending medium, but required the presence of a fermentable sugar. d-Galactose and maltose caused shock excretion only when yeast was previously adapted to these sugars. Limiting glucose concentrations prevented reabsorption of amino acids, and a further decrease in glucose concentration also limited excretion. Shock excretion was strikingly reduced when the temperature of the suspending medium was lowered.

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

    PubMed

    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

  7. Urinary excretion of bile acid glucosides and glucuronides in extrahepatic cholestasis.

    PubMed

    Wietholtz, H; Marschall, H U; Reuschenbach, R; Matern, H; Matern, S

    1991-04-01

    Recently the formation of bile acid glucosides has been described as a novel conjugation mechanism in vitro and in vivo. In 10 patients with extrahepatic cholestasis caused by carcinoma of the head of the pancreas we investigated excretion rates and profiles of urinary bile acid glucosides. Urinary bile acid glucosides and, for comparison, bile acid glucuronides were extracted and characterized according to established methods. In controls total urinary bile acid glucoside excretion was 0.22 +/- 0.03 mumol/24 hr (mean +/- S.E.M.)-in the range of bile acid glucuronide excretion (0.41 +/- 0.06 mumol/24 hr; mean +/- S.E.M.). A gas chromatography-mass spectrometry-characterized trihydroxy bile acid glucoside of still-unknown hydroxyl positions accounted for 65% of total urinary bile acid glucosides. In extrahepatic cholestasis total urinary bile acid glucoside excretion was 0.52 +/- 0.13 mumol/24 hr (mean +/- SEM), yet significantly lower than bile acid glucuronide excretion (1.53 +/- 0.13 mumol/24 hr; mean +/- SEM; p less than 0.001). In cholestasis the primary bile acid derivatives cholic and chenodeoxycholic acid glucosides amounted to 90%, whereas the trihydroxy bile acid glucoside had decreased to 5% of total bile acid glucoside excretion, indicating its alteration during enterohepatic circulation. The data establish the composition and quantity of urinary bile acid glucosides in healthy controls and cholestasis and constitute a quantitative comparison with another glycosidic conjugation reaction, bile acid glucuronidation.

  8. Controlled exercise effects on chromium excretion of trained and untrained runners consuming a constant diet

    SciTech Connect

    Anderson, R.A.; Bryden, N.A.; Polansky, M.M.; Deuster, P.A.

    1986-03-05

    To determine if degree of training effects urinary Cr losses, Cr excretion of 8 adult trained and 5 untrained runners was determined on rest days and following exercise at 90% of maximal oxygen uptake on a treadmill to exhaustion with 30 second exercise and 30 second rest periods. Subjects were fed a constant daily diet containing 9 ..mu..g of Cr per 1000 calories to minimize changes due to diet. Maximal oxygen consumption of the trained runners was in the good or above range based upon their age and that of the untrained runners was average or below. While consuming the control diet, basal urinary Cr excretion of subjects who exercise regularly was significantly lower than that of the sedentary control subjects, 0.09 +/- 0.01 and 0.21 +/- 0.03 ..mu..g/day (mean +/- SEM), respectively. Daily urinary Cr excretion of trained subjects was significantly higher on the day of a single exercise bout at 90% of maximal oxygen consumption compared to nonexercise days, 0.12 +/- 0.02 and 0.09 +/- 0.01 ..mu..g/day, respectively. Urinary Cr excretion of 5 untrained subjects was not altered following controlled exercise. These data demonstrate that basal urinary Cr excretion and excretion in response to exercise are related to maximal oxygen consumption and therefore degree of fitness.

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

    PubMed Central

    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

  10. Geographical and temporal differences in the urinary excretion of inorganic arsenic: a Belgian population study.

    PubMed Central

    Buchet, J P; Staessen, J; Roels, H; Lauwerys, R; Fagard, R

    1996-01-01

    OBJECTIVE: This Belgian study assessed the geographical and temporal differences in the exposure of the population to inorganic arsenic, a known carcinogen. METHODS: In the CadmiBel study (1985-9) the 24 h urinary arsenic excretion was measured, as an index of recent exposure, in industrialised cities (Liège: n = 664, Charleroi: n = 291), in a rural control area (Hechtel-Eksel: n = 397), and in rural districts in which the population had possibly been exposed through the drinking water or the emissions of nonferrous smelters (Wezel: n = 93, Lommel: n = 111, and Pelt: n = 133). In the PheeCad study, in 1991-5, the rural areas (n = 609) were re-examined together with an urban control area (Leuven: n = 152). RESULTS: The CadmiBel results showed that after adjustment for sex, age, and body mass index, the 24 h arsenic excretion was on average low in Liège (91 nmol), Charleroi (155 nmol), Hechtel-Eksel (144 nmol), and Wezel (158 nmol), whereas the highest excretions were found in Lommel (570 nmol) and Pelt (373 nmol). During the PheeCad study, the mean 24 h arsenic excretion in the rural areas ranged from 81 to 111 nmol. This was lower than six years earlier and similar to the excretion in the control town (108 nmol). Longitudinal studies in 529 people living in the rural areas confirmed that their 24 h arsenic excretion had decreased (P < 0.001) from 222 to 100 nmol. As well as the drinking water, industry was likely to be a source of the increased exposure in Lommel and Pelt in 1985-9, because at that time the urinary arsenic excretion did not follow the regional differences in the arsenic content of the drinking water, because the fall in the arsenic excretion over time coincided with the implementation by industry of stricter environmental regulations, because in individual subjects the urinary arsenic excretion was inversely correlated with the distance to the nearest smelter, and because an increased arsenic excretion was only found downwind from the main

  11. Renal electrolyte excretion and renin release during calcium and parathormone infusions in conscious rabbits.

    PubMed Central

    Peart, W S; Roddis, S A; Unwin, R J

    1986-01-01

    Following a random block experimental design in each case, three repeated measurement studies were carried out in three different groups of conscious rabbits, to investigate the renal effects of increasing doses of intravenous calcium chloride (CaCl2) and bovine parathyroid hormone (PTH). In the first study, each rabbit received either CaCl2 (0.15, 0.3, 0.5 or 1.0 mg kg-1 min-1) or vehicle alone (control) for 160 min. In the second study, rabbits were given either PTH (0.15 microgram kg-1 min-1), CaCl2 (1.0 mg kg-1 min-1), PTH plus CaCl2 (0.15 microgram kg-1 min-1 and 1.0 mg kg-1 min-1, respectively) or vehicle alone; PTH was infused for just over 60 min. In the third study, a much smaller dose (0.05 mg kg-1 min-1) of CaCl2 was infused for 100 min. CaCl2 infusion produced a striking fall in fractional excretion of sodium of at least 50% (P less than 0.01), but this was not dose related, being almost maximal at the smaller doses infused. Although this effect was evident in the absence of any changes in total plasma calcium concentration at the lower doses of CaCl2, renal calcium excretion was increased between 2- and 20-fold (P less than 0.01) at all doses infused. Fractional excretion of chloride doubled at the two higher doses of CaCl2 (P less than 0.01), but potassium excretion was unchanged. There were no consistent alterations in mean arterial blood pressure, effective renal plasma flow, glomerular filtration rate or plasma renin activity (PRA); total plasma calcium concentration was consistently elevated only during infusion of the high dose by just under 1 mmol l-1. PTH infusion had no measured effect on fractional excretion of sodium or renal calcium excretion, but doubled fractional potassium excretion (P less than 0.05). Heart rate and PRA increased (P less than 0.01 and less than 0.05, respectively), the latter by 50%, but systemic pressure and renal haemodynamics were not significantly affected. By contrast, PTH infused with CaCl2 produced a 4-fold rise

  12. 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

    PubMed Central

    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

  13. Perinatal taurine exposure alters renal potassium excretion mechanisms in adult conscious rats.

    PubMed

    Roysommuti, Sanya; Malila, Pisamai; Lerdweeraphon, Wichaporn; Jirakulsomchok, Dusit; Wyss, J Michael

    2010-08-24

    Perinatal taurine exposure has long-term effects on the arterial pressure and renal function. This study tests its influence on renal potassium excretion in young adult, conscious rats. Female Sprague-Dawley rats were fed normal rat chow and given water alone (C), 3% beta-alanine in water (taurine depletion, TD) or 3% taurine in water (taurine supplementation, TS), either from conception until delivery (fetal period; TDF or TSF) or from delivery until weaning (lactation period; TDL or TSL). In Experiment 1, male offspring were fed normal rat chow and tap water, while in Experiment 2, beta-alanine and taurine were treated from conception until weaning and then female pups were fed normal rat chow and 5% glucose in drinking water (CG, TDG or TSG) or water alone (CW, TDW or TSW). At 7-8 weeks of age, renal potassium excretion was measured at rest and after an acute saline load (5% of body weight) in conscious, restrained rats. Although all male groups displayed similar renal potassium excretion, TSF rats slightly increased fractional potassium excretion at rest but not in response to saline load, whereas TDF did the opposite. Plasma potassium concentration was only slightly altered by the diet manipulations. In female offspring, none of the perinatal treatments significantly altered renal potassium excretion at rest or after saline load. High sugar intake slightly decreased potassium excretion at rest in TDG and TSG, but only the TDG group displayed a decreased response to saline load. The present data indicates that perinatal taurine exposure only mildly influences renal potassium excretion in adult male and female rats.

  14. Factors Altering Pyruvate Excretion in a Glycogen Storage Mutant of the Cyanobacterium, Synechococcus PCC7942

    PubMed Central

    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

  15. Staphylococcal Major Autolysin (Atl) Is Involved in Excretion of Cytoplasmic Proteins*

    PubMed Central

    Pasztor, Linda; Ziebandt, Anne-Kathrin; Nega, Mulugeta; Schlag, Martin; Haase, Sabine; Franz-Wachtel, Mirita; Madlung, Johannes; Nordheim, Alfred; Heinrichs, David E.; Götz, Friedrich

    2010-01-01

    Many microorganisms excrete typical cytoplasmic proteins into the culture supernatant. As none of the classical secretion systems appears to be involved, this type of secretion was referred to as “nonclassical protein secretion.” Here, we demonstrate that in Staphylococcus aureus the major autolysin plays a crucial role in release of cytoplasmic proteins. Comparative secretome analysis revealed that in the wild type S. aureus strain, 22 typical cytoplasmic proteins were excreted into the culture supernatant, although in the atl mutant they were significantly decreased. The presence or absence of prophages had little influence on the secretome pattern. In the atl mutant, secondary peptidoglycan hydrolases were increased in the secretome; the corresponding genes were transcriptionally up-regulated suggesting a compensatory mechanism for the atl mutation. Using glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as a cytoplasmic indicator enzyme, we showed that all clinical isolates tested excreted this protein. In the wall teichoic acid-deficient tagO mutant with its increased autolysis activity, GAPDH was excreted in even higher amounts than in the WT, confirming the importance of autolysis in excretion of cytoplasmic proteins. To answer the question of how discriminatory the excretion of cytoplasmic proteins is, we performed a two-dimensional PAGE of cytoplasmic proteins isolated from WT. Surprisingly, the most abundant proteins in the cytoplasm were not found in the secretome of the WT, suggesting that there exists a selection mechanism in the excretion of cytoplasmic proteins. As the major autolysin binds at the septum site, we assume that the proteins are preferentially released at and during septum formation. PMID:20847047

  16. Relationship between circadian blood pressure variation and circadian protein excretion in CKD.

    PubMed

    Agarwal, Rajiv

    2007-09-01

    Circadian blood pressure changes are blunted in patients with chronic kidney disease (CKD). Proteinuria is the most important correlate of hypertension in CKD. However, little is known about the influence of circadian blood pressure changes and variation in protein excretion rate. Furthermore, the impact of blood pressure components, e.g., mean arterial pressure and pulse pressure, on proteinuria has not been evaluated. To analyze the relationship of circadian changes in blood pressure on urinary protein excretion patterns, glomerular filtration rate was measured with iothalamate clearance and 24-h ambulatory blood pressure with SpaceLabs 90207 monitor in 22 patients with CKD. It was found that hourly protein excretion rates were 31% higher during the night. Excretion results of sodium, potassium, chloride, urea, and creatinine were also between 30 and 40% higher at night. Systolic, mean arterial, and pulse pressures but not diastolic pressure were related to daytime protein excretion rate. At night, the relationship of systolic, diastolic, and mean arterial pressures was significantly lower and essentially flat with respect to protein excretion rate, but the relationship of pulse pressure and proteinuria was not different from that seen during the day. Circadian variation in blood pressure did not impact circadian sodium excretion rate. In conclusion, these data suggest that patients with CKD have patterns of proteinuria that share different relationships with blood pressure components depending on the awake-sleep state. Pulse pressure is related to proteinuria independent of the awake-sleep state. Reducing mean arterial pressure during the day and pulse pressure during the day or night may be effective antiproteinuric strategies. PMID:17581923

  17. Comparative effects of lactulose and magnesium sulfate on urea metabolism and nitrogen excretion in cirrhotic subjects.

    PubMed

    Weber, F L; Fresard, K M

    1981-05-01

    In previous studies with cirrhotic subjects administration of oral lactulose caused a reduction in the urea production rate associated with an increase in fecal nitrogen excretion. The change in urea production rate in response to lactulose therapy was an indirect measure of a reduction in total gut ammonia production. In this study, the effect of magnesium sulfate administration was compared with lactulose therapy in 5 cirrhotic subjects to determine whether the effects of lactulose on nitrogen metabolism might be attributed to a nonspecific, cathartic effect. Both magnesium sulfate (5-15 g/day) and lactulose (40-80 g/day) caused significant and comparable increases in stool weight, solids, and total nitrogen. Only lactulose caused a reduction in fecal pH. Magnesium sulfate had no significant effect on the urea production rate or urinary nitrogen excretion, whereas lactulose caused a 25% reduction in the urea production rate and an 18% reduction in urinary nitrogen excretion. The latter was accounted for by a fall in urinary urea. Nitrogen balance was more negative during magnesium sulfate than during control or lactulose periods since magnesium sulfate increased fecal nitrogen without altering urinary nitrogen excretion. These data demonstrated that the effects of lactulose on nitrogen excretion and urea metabolism were not duplicated by equivalent cathartic doses of magnesium sulfate. PMID:7202981

  18. Changes in nephrogenous cyclic AMP excretion and plasma cyclic AMP following treatment of hyperthyroidism.

    PubMed

    Naafs, M A; van der Velden, P C; Fischer, H R; Koorevaar, G; van Duin, S; Hackeng, W H; Schopman, W; Silberbusch, J

    1984-08-01

    Plasma cyclic AMP (PcAMP) concentration and the excretion of cyclic AMP/dl GF were estimated in 11 thyrotoxic patients before and after medical treatment. PcAMP concentrations were significantly higher during hyperthyroidism (2.30 +/- 0.69 vs 1.88 +/- 0.71 nmol/dl; P less than 0.05), and total urinary cyclic AMP (TcAMP) excretion showed no significant changes (3.24 +/- 0.64 vs 3.44 +/- 1.77 nmol/dl GF). Nephrogenous (NcAMP) excretion rose significantly (1.00 +/- 0.82 vs 1.68 +/- 1.31 mmol/dl GF; P less than 0.025). The increase in NcAMP excretion correlated significantly with the decrease in serum T3 levels (r = -0.46; P less than 0.05). Serum iPTH levels showed no significant change. Both the serum Ca, corrected for serum total protein and TmPO4/GFR declined after treatment (respectively 2.44 +/- 0.13 vs 2.33 +/- 0.08 mmol/l; P less than 0.05 and 1.18 +/- 0.29 vs 1.05 +/- 0.22 mmol/l; P less than 0.05). It is concluded that the rise in NcAMP excretion corroborates the concept of increasing parathyroid activity following the treatment of hyperthyroidism. PMID:6206676

  19. Effect of dietary caffeine and theophylline on urinary calcium excretion in the adult rat.

    PubMed

    Whiting, S J; Whitney, H L

    1987-07-01

    The chronic effects of dietary caffeine or theophylline on urinary calcium excretion were investigated in the adult male rat. When caffeine was added at two concentrations, 0.75 and 1.50 g/kg diet, 24-h urinary calcium excretion rose 300 and 450% on d 7, and 200 and 330% on d 14, respectively. There were no changes in the 24-h urinary excretion of phosphate, sulfate, sodium and cAMP nor did urine volume change. The high dose of caffeine was compared to an equimolar dose of theophylline (1.39 g/kg diet) in both Wistar and Sprague-Dawley rats. Urinary calcium excretion in theophylline-treated rats was significantly greater than in caffeine-treated rats on all sampling days and in both strains of rat; the calciuric effect lasted at least 22 d. When rats were given indomethacin (3.3 mg/kg diet) the calciuria induced by caffeine and theophylline was abolished, and sodium excretion in all groups was reduced by 35-50%, but urine volume was unchanged. The calciuria of methylxanthine feeding may result from a prostaglandin-mediated process distinct from diuresis. PMID:3612301

  20. Urinary excretion of isomers of biliverdin after destruction in vivo of haemoproteins and haemin.

    PubMed Central

    Hirota, K; Yamamoto, S; Itano, H A

    1985-01-01

    The amount and isomeric composition of urinary biliverdin in rabbits were analysed by h.p.l.c. Physiological values were maintained after the injection of haemin. On the other hand, when haemoglobins from several mammalian species were injected into rabbits, the excretion of biliverdin-IX alpha and biliverdin-IX beta were increased 6-18-fold and 32-66-fold respectively over physiological excretion. Injection of myoglobin resulted in a 44-fold increase in excretion of the IX alpha-isomer. Coupled oxidation with ascorbate of haemoglobin and myoglobin by oxygen produced mainly the IX alpha- and IX beta-isomers from haemoglobin and the IX alpha-isomer from myoglobin. The destruction of part of the haem from injected haemoproteins by non-enzymic chemical degradation would account for the observed respective increases in the excretion of biliverdin isomers. The excretion of biliverdin isomers after the injection of phenylhydrazine into rabbits was similar to that after the injection of haemoglobin. PMID:4038276

  1. Ecological and sociodemographic effects on urinary catecholamine excretion in adult Samoans

    PubMed Central

    Bergey, Meredith R.; Steele, Matthew S.; Bereiter, David A.; Viali, Satupaitea; McGarvey, Stephen T.

    2013-01-01

    Background Ecological and sociodemographic correlates of stress may contribute to cardiovascular disease risk in modernizing Samoans. Aim The effects of peri-urban vs rural residence, education, occupation, caffeine intake and cigarette consumption on urinary catecholamine excretion were studied in Samoan adults. Subjects and methods Five hundred and seven participants, aged 29–69 years, were randomly selected from nine villages throughout Samoa. Sociodemographic and lifestyle factors were assessed by questionnaire. Epinephrine and norepinephrine excretion rates were measured by high performance liquid chromatography with electrochemical detection in overnight urine samples. Age (≤40 vs >40 years) and gender-specific regression models were estimated to detect associations with BMI-adjusted catecholamine excretion. Results Norepinephrine was significantly higher in peri-urban young men and older women. Epinephrine was significantly higher in peri-urban older men. Adjustment for caffeine attenuated the relationship between residence and norepinephrine in young women. Conclusion General residential exposure to modernization in urban villages is a significant correlate of increased overnight catecholamine excretion rates and is consistent with past studies. Caffeine consumption in younger women plays a complex role in stress-related catecholamine excretion. Further studies of individual level attitudinal and behavioural factors in Samoans are needed to understand psychosocial stress, physiologic arousal and health. PMID:20836724

  2. Absorption, distribution, metabolism and excretion of YM466, a novel factor Xa inhibitor, in rats.

    PubMed

    Mano, Yuji; Sonoda, Takuya; Nakamura, Eiji; Usui, Takashi; Kamimura, Hidetaka

    2004-09-01

    YM466 is a novel factor Xa inhibitor for the treatment of thrombosis. The absorption, distribution, metabolism and excretion of YM466 were investigated in male Fisher rats after a single oral administration. YM466 was absorbed rapidly from all segments of the gastrointestinal tract except the stomach. After oral dosing, the plasma concentration of (14)C-YM466 reached a maximum within 0.5 h, and declined rapidly with an elimination half-life of 0.64 h. The unchanged YM466 accounted for almost all of its radioactivity, suggesting a minimal metabolism in rats. This was also supported by the finding that no metabolites were observed in bile and urine after oral dosing of (14)C-YM466. The distribution of (14)C-YM466 in tissue was evaluated and the liver and kidney were the organs with radioactivity concentrations consistently higher than that of plasma. Cumulative biliary and urinary excretion of radioactivity in bile duct-cannulated rats was 29.5% and 7.6%, respectively, indicating prominent excretion into bile after oral dosing. This was consistent with the finding that 76.1% and 25.2% of radioactivity dosed were excreted to faeces and urine, respectively, after i.v. dosing. These results suggest that YM466 was rapidly absorbed and then subjected to biliary excretion with a minimal metabolism after oral dosing to rats. PMID:15334624

  3. Effect of octreotide acetate on the plasma concentration and urinary excretion of uridine and purine bases.

    PubMed

    Yamamoto, Tetsuya; Moriwaki, Yuji; Takahashi, Sumio; Tsutsumi, Zenta; Ka, Tsuneyoshi; Hada, Toshikazu

    2002-04-01

    To determine the effect of octreotide acetate on urinary excretion of uric acid and plasma concentration of uridine, we subcutaneously administered octreotide acetate (1 microg/kg of body weight) to 5 healthy subjects. Ninety minutes after administration, octreotide acetate increased the plasma concentration of uridine by 15% and decreased the plasma concentration of glucagon by 24% and that of insulin to below the detection limits. In addition, octreotide acetate decreased the urinary excretion of uric acid, sodium, and chloride by 60%, 40%, and 38%, respectively, at 1 hour after administration. However, octreotide acetate did not affect the concentrations of hypoxanthine, xanthine, uric acid, cyclic AMP in plasma, lactic acid and pyruvic acid in blood, urinary excretion of hypoxanthine and xanthine, or creatinine clearance. From these results, we speculated that octreotide acetate decreases the urinary excretion of uric acid by decreasing the concentration of glucagon and/or urinary excretion of sodium, and increases the plasma concentration of uridine via decreased concentrations of glucagon and insulin.

  4. Coupling between chloride absorption and base excretion in isolated skin of Rana esculenta.

    PubMed

    Ehrenfeld, J; Garcia-Romeu, F

    1978-07-01

    The net excretory fluxes of base (HCO3- or OH-) and the unidirectional fluxes of chloride were measured and their relationship examined in isolated frog skin maintained in open- or short-circuit (OC and SC) conditions. When the mucosal solution was a 2 mM choline chloride solution and the serosal solution a Ringer solution buffered with a HCO3-/CO2 mixture, the rate of base excretion was -105 +/- 10 in OC and -60 +/- 7 neq h-1 cm-2 in SC. A highly significant correlation was observed between the influx of chloride and the excretion of base. As a function of external chloride both these parameters followed saturation kinetics, Vmax being obtained for a chloride concentration below 2 mM. The removal of chloride in the external solution was followed by a 70 or 100% inhibition of base excretion in OC and SC conditions, respectively. Chloride transport is dependent on the presence of a HCO3-/CO2 mixture in the internal or the external medium. This transport, as well as base excretion, is inhibited to a considerable extent by removal of HCO3-/CO2 or by acetazolamide (10(-3) M). This investigation characterizes a saturable transport system in which chloride absorption and base excretion are coupled. PMID:307916

  5. Longitudinal gonadal steroid excretion in free-living male and female meerkats (Suricata suricatta).

    PubMed

    Moss, A M; Clutton-Brock, T H; Monfort, S L

    2001-05-01

    Slender-tailed meerkats (Suricata suricatta) are small, diurnal, cooperatively breeding mongooses of the family Herpestidae. A prerequisite to fully understanding the mating system of meerkats is the development of a normative reproductive-endocrine database. This study examined longitudinal gonadal steroid excretion in all adult and juvenile individuals of both sexes within a social group of free-living meerkats sampled across an entire breeding season. The specific objectives of this study were to (1) validate noninvasive (fecal and urinary) gonadal steroid hormone monitoring techniques in male (testosterone) and female (estrogens, progestagens) meerkats; (2) test the feasibility of using these noninvasive methods under field conditions; (3) characterize the endocrine correlates associated with the female reproductive cycle, including estrus, gestation, and postpartum estrus; (4) examine longitudinal androgen excretion in males; and (5) determine whether social status (i.e., dominant versus subordinate) affected gonadal steroid excretion. In females, the results demonstrated the physiological validity of noninvasive monitoring in meerkats by corresponding excretory hormone concentrations to major reproductive events (i.e., estrous, pregnancy, parturition). Hormone excretory patterns during estrous intervals suggested possible mechanisms whereby reproductive suppression may operate in female meerkats. In males, androgen excretion did not correspond to changes in reproductive and aggressive behaviors, suggesting that dominance, and hence breeding access to females, was not regulated strictly by gonadal steroid production. The consistency in androgen excretion among male meerkats indicated that reproductive suppression may be mediated by behavioral (i.e., intermale aggression) rather than physiological (i.e., depressed spermatogenesis) mechanisms.

  6. Characterization of Al-responsive citrate excretion and citrate-transporting MATEs in Eucalyptus camaldulensis.

    PubMed

    Sawaki, Yoshiharu; Kihara-Doi, Tomonori; Kobayashi, Yuriko; Nishikubo, Nobuyuki; Kawazu, Tetsu; Kobayashi, Yasufumi; Koyama, Hiroyuki; Sato, Shigeru

    2013-04-01

    Many plant species excrete organic acids into the rhizosphere in response to aluminum stress to protect sensitive cells from aluminum rhizotoxicity. When the roots of Eucalyptus camaldulensis, a major source of pulp production, were incubated in aluminum-toxic medium, citrate released into the solution increased as a function of time. Citrate excretion was inducible by aluminum, but not by copper or sodium chloride stresses. This indicated that citrate is the major responsive organic acid released from the roots of this plant species to protect the root tips from aluminum damage. Four genes highly homologs to known citrate-transporting multidrugs and toxic compounds exclusion proteins, named EcMATE1-4, were isolated using polymerase chain reaction-based cloning techniques. Their predicted proteins included 12 membrane spanning domains, a common structural feature of citrate-transporting MATE proteins, and consisted of 502-579 amino acids with >60 % homology to orthologous genes in other plant species. One of the homologs, designated EcMATE1, was expressed in the roots more abundantly than in the shoots and in response to both Al and low pH stresses. Ectopic expression of EcMATE1 and 3 in tobacco hairy roots enhanced Al-responsive citrate excretion. Pharmacological characterization indicated that Al-responsive citrate excretion involved a protein phosphorylation/dephosphorylation process. These results indicate that citrate excretion through citrate-transporting multidrugs and toxic compounds exclusion proteins is one of the important aluminum-tolerance mechanisms in Eucalyptus camaldulensis.

  7. Investment in boney defensive traits alters organismal stoichiometry and excretion in fish.

    PubMed

    El-Sabaawi, Rana W; Warbanski, Misha L; Rudman, Seth M; Hovel, Rachel; Matthews, Blake

    2016-08-01

    Understanding how trait diversification alters ecosystem processes is an important goal for ecological and evolutionary studies. Ecological stoichiometry provides a framework for predicting how traits affect ecosystem function. The growth rate hypothesis of ecological stoichiometry links growth and phosphorus (P) body composition in taxa where nucleic acids are a significant pool of body P. In vertebrates, however, most of the P is bound within bone, and organisms with boney structures can vary in terms of the relative contributions of bones to body composition. Threespine stickleback populations have substantial variation in boney armour plating. Shaped by natural selection, this variation provides a model system to study the links between evolution of bone content, elemental body composition, and P excretion. We measure carbon:nitrogen:P body composition from stickleback populations that vary in armour phenotype. We develop a mechanistic mass-balance model to explore factors affecting P excretion, and measure P excretion from two populations with contrasting armour phenotypes. Completely armoured morphs have higher body %P but excrete more P per unit body mass than other morphs. The model suggests that such differences are driven by phenotypic differences in P intake as well as body %P composition. Our results show that while investment in boney traits alters the elemental composition of vertebrate bodies, excretion rates depend on how acquisition and assimilation traits covary with boney trait investment. These results also provide a stoichiometric hypothesis to explain the repeated loss of boney armour in threespine sticklebacks upon colonizing freshwater ecosystems.

  8. Essential trace metal excretion from rats with lead exposure and during chelation therapy.

    PubMed

    Victery, W; Miller, C R; Goyer, R A

    1986-02-01

    Urinary excretion of lead, zinc, calcium, magnesium, iron, copper, sodium, and potassium was measured in rats daily for 1 week after a 6-week exposure to 10,000 micrograms/ml lead in drinking water. Beginning on the third day, half of the lead-exposed and control rats were injected intraperitoneally with calcium disodium ethylenediaminetetraacetate (EDTA) daily for 3 days. Whole blood, plasma, and kidney metal concentrations were determined from samples obtained at the end of the experiment. Exposure to lead increased urinary excretion, not only of lead, but also of calcium, magnesium, zinc, copper, and iron. Excretion of sodium and potassium was not altered. Chelation therapy further increased excretion of lead, zinc, copper, and iron, but not magnesium. The increase in calcium excretion during chelation treatment (beyond that resulting from lead exposure per se) was accounted for by the Ca content of CaNa2-EDTA. EDTA treatment increased renal concentration of zinc but lowered renal concentration of lead, copper, and iron. These multimetal alterations may have implications for essential metal supplementation, particularly zinc, in persons being given chelation agents for excess lead exposure and in infants and children with low-level lead exposure not necessarily requiring chelation therapy.

  9. Urinary Excretion of Neutrophil Gelatinase-Associated Lipocalin in Diabetic Rats

    PubMed Central

    Arellano-Buendía, Abraham Said; García-Arroyo, Fernando Enrique; Cristóbal-García, Magdalena; Loredo-Mendoza, María Lilia; Tapia-Rodríguez, Edilia; Sánchez-Lozada, Laura Gabriela; Osorio-Alonso, Horacio

    2014-01-01

    Recent studies suggest that tubular damage precedes glomerular damage in the progression of diabetic nephropathy. Therefore, we evaluated oxidative stress and urinary excretion of tubular proteins as markers of tubular dysfunction. Methods. Diabetes was induced in rats by streptozotocin administration (50 mg/kg). Oxidative stress was assessed by measuring the activity of catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD); additionally, expression levels of 3-nitrotyrosine (3-NT), 4-hydroxynonenal (4-HNE), and oxidized protein (OP) were quantified. Whole glomerular filtration rate (GFR) was measured. Urinary excretion of neutrophil gelatinase-associated lipocalin (uNGAL), osteopontin (uOPN), and N-acetyl-β-D-glucosaminidase (uNAG) was also determined. Results. Diabetic rats showed an increase in uNGAL excretion 7 days following induction of diabetes. Diuresis, proteinuria, albuminuria, creatinine clearance, and GFR were significantly increased by 30 days after induction. Furthermore, there was an increase in both CAT and SOD activity, in addition to 3-NT, 4-HNE, and OP expression levels. However, GPx activity was lower. Serum levels of NGAL and OPN, as well as excretion levels of uNGAL, uOPN, and uNAG, were increased in diabetics. Tubular damage was observed by 7 days after diabetes induction and was further aggravated by 30 days after induction. Conclusion. The tubular dysfunction evidenced by urinary excretion of NGAL precedes oxidative stress during diabetes. PMID:25243053

  10. Estrogen excretion patterns and plasma levels in vegetarian and omnivorous women.

    PubMed

    Goldin, B R; Adlercreutz, H; Gorbach, S L; Warram, J H; Dwyer, J T; Swenson, L; Woods, M N

    1982-12-16

    We studied 10 vegetarian and 10 nonvegetarian premenopausal women on four occasions approximately four months apart. During each study period, the participants kept three-day dietary records, and estrogens were measured in plasma, urinary, and fecal samples. Vegetarians consumed less total fat than omnivores did (30 per cent of total calories, as compared with 40 per cent) and more dietary fiber (28 g per day, as compared with 12 g). There was a positive correlation between fecal weight and fecal excretion of estrogens in both groups (P less than 0.001), with vegetarians having higher fecal weight and increased fecal excretion of estrogens. Urinary excretion of estriol was lower in vegetarians (P less than 0.05), and their plasma levels of estrone and estradiol were negatively correlated with fecal excretion of estrogen (P = 0.005). Among the vegetarians the beta-glucuronidase activity of fecal bacteria was significantly reduced (P = 0.05). We conclude that vegetarian women have an increased fecal output, which leads to increased fecal excretion of estrogen and a decreased plasma concentration of estrogen.

  11. Longitudinal gonadal steroid excretion in free-living male and female meerkats (Suricata suricatta).

    PubMed

    Moss, A M; Clutton-Brock, T H; Monfort, S L

    2001-05-01

    Slender-tailed meerkats (Suricata suricatta) are small, diurnal, cooperatively breeding mongooses of the family Herpestidae. A prerequisite to fully understanding the mating system of meerkats is the development of a normative reproductive-endocrine database. This study examined longitudinal gonadal steroid excretion in all adult and juvenile individuals of both sexes within a social group of free-living meerkats sampled across an entire breeding season. The specific objectives of this study were to (1) validate noninvasive (fecal and urinary) gonadal steroid hormone monitoring techniques in male (testosterone) and female (estrogens, progestagens) meerkats; (2) test the feasibility of using these noninvasive methods under field conditions; (3) characterize the endocrine correlates associated with the female reproductive cycle, including estrus, gestation, and postpartum estrus; (4) examine longitudinal androgen excretion in males; and (5) determine whether social status (i.e., dominant versus subordinate) affected gonadal steroid excretion. In females, the results demonstrated the physiological validity of noninvasive monitoring in meerkats by corresponding excretory hormone concentrations to major reproductive events (i.e., estrous, pregnancy, parturition). Hormone excretory patterns during estrous intervals suggested possible mechanisms whereby reproductive suppression may operate in female meerkats. In males, androgen excretion did not correspond to changes in reproductive and aggressive behaviors, suggesting that dominance, and hence breeding access to females, was not regulated strictly by gonadal steroid production. The consistency in androgen excretion among male meerkats indicated that reproductive suppression may be mediated by behavioral (i.e., intermale aggression) rather than physiological (i.e., depressed spermatogenesis) mechanisms. PMID:11316421

  12. Elevated urinary excretion of orotic acid in sheep caused by intraruminal infusion of sodium propionate.

    PubMed

    Bödeker, D; Martens, H

    1992-06-01

    1. The effect of sodium propionate on urinary excretion of orotic acid was investigated. 2. Solutions containing sodium propionate or NaCl, 750 mM/day each, were continuously infused into the rumen for 10 days. 3. During NaCl infusion, an urinary orotic acid excretion of 290 +/- 80 micrograms/day was noted. The intraruminal infusion of sodium propionate raised the concentration of propionic acid in the rumen fluid from 14.0 +/- 0.9 to 26.9 +/- 1.9 mM. 4. During this experimental period the excretion of orotic acid via urine significantly increased to 492 +/- 30 micrograms/day. Parameters of nitrogen balance were not altered by propionate. 5. It is suggested that the site of propionate action in intact sheep is in the pyrimidine synthesis pathway.

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

    NASA Astrophysics Data System (ADS)

    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

  14. [The course of the catecholamine excretion during combination anaesthesia with halothane and thalamonal (author's transl)].

    PubMed

    Freiberger, K U; Hack, G; Havers, L

    1975-11-01

    On 10 patients who had to undergo a ca. 4 hour operation of the lower abdominal region, the pattern of catecholamine excretion before, during and after operation was traced. 1. A decrease of systolic blood pressure on average of 80 mm Hg, in correlation to the concentration of Halothane and Thalamonal, was recorded. 2. The excretion of adrenaline and noradrenalin was significantly lower during anaesthesia as compared with the initial value, suggesting a depression of sympathoadrenal system. 3. The postoperative amount of adrenaline and especially noradrenaline increased markedly, when anaesthesia worn off, postoperative shivering started, and surgical wounds caused pain. 4. The excretion of urine during operation was slightly reduced, the renal output showed normal amounts, when calculated up to 24 hours. The results show, that the combined use of halothane an thalamonal because of its depressant effects on the sympathoadrenal system is capable of reducing the liberation of catecholamines during anaesthesia.

  15. Effect of 14 days of bed rest on urine metabolite excretion and plasma enzyme levels

    NASA Technical Reports Server (NTRS)

    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.

  16. The first instance of a cat excreting Echinococcus multilocularis eggs in Japan.

    PubMed

    Nonaka, Nariaki; Hirokawa, Haruki; Inoue, Takashi; Nakao, Ryo; Ganzorig, Sumiya; Kobayashi, Fumio; Inagaki, Masakazu; Egoshi, Kentaro; Kamiya, Masao; Oku, Yuzaburo

    2008-12-01

    A cat excreting Echinococcus multilocularis eggs was recently identified in Hokkaido, representing the first such observation in Japan. The cat was raised free-range and frequently ate rodents. Fecal egg examination revealed eggs of taeniids (EPG: 440) and Spirometra spp. (EPG: >1000). PCR targeting part of the mitochondrial cytochrome c oxidase subunit I gene of E. multilocularis was positive with DNA from 3 single isolated taeniid eggs, and sequence analysis of one amplicon confirmed E. multilocularis. The results indicated that the eggs of E. multilocularis distributed in Hokkaido can be excreted in cat feces, and suggested the necessity of further studies to clarify whether the eggs excreted in cat feces are infective and thus whether cats can serve as infectious source to humans in Japan.

  17. Annual pattern of fecal corticoid excretion in captive Red-tailed parrots (Amazona brasiliensis).

    PubMed

    Popp, Lucyenne G; Serafini, Patrícia P; Reghelin, Angela L S; Spercoski, Katherinne Maria; Roper, James J; Morais, Rosana N

    2008-05-01

    Annual patterns of fecal corticoid excretion were analyzed in the threatened Red-tailed parrot (Amazona brasiliensis) in captivity. Corticoid concentration over the 15 months of the study (mean +/- standard error, 12.6 +/- 0.32 ng g(-1), n = 585) was lowest around May (the southern Fall), and greatest around September (late winter), just prior to their normal breeding period. Corticoid excretion follows a seasonal pattern best explained by reproductive cycles rather than climate, although climate may be involved in the timing of corticoid excretion. Fecal corticoids also show promise as a tool to measure stress levels. We demonstrate that fecal corticoid measurement is a simple, yet efficient method for monitoring adrenocortical activity in captive, and perhaps wild, parrots. Monitoring adrenocortical activity can inform researchers about imposed stress in captivity, whether pair-bonds are forming in captive birds, and of the timing of breeding both in captivity and in nature.

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

    NASA Astrophysics Data System (ADS)

    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.

  19. Urinary sodium excretion and ambulatory blood pressure findings in patients with hypertension.

    PubMed

    Afsar, Baris; Elsurer, Rengin; Kirkpantur, Alper; Kanbay, Mehmet

    2015-03-01

    Use of ambulatory blood pressure (BP) monitoring (ABPM) allows for identification of dipping, nondipping, extreme dipping, and reverse dipping of BP. Using office BP and ABPM, hypertension subtypes can be identified: sustained normotension (SNT), white-coat hypertension, masked hypertension, and sustained hypertension. The comparison of hemodynamic parameters and salt intake has not been investigated among these patient groups. Office BP, ABPM, augmentation index (AIx), pulse wave velocity (PWV), cardiac output (CO), and total peripheral resistance (TPR) were automatically measured. Estimation of salt intake was assessed by 24-hour urinary sodium excretion. Urinary sodium excretion was not different among groups. AIx, PWV, CO, and TPR were lowest in patients with SNT. CO was lowest while AIx adjusted for a heart rate of 75 beats per minute, PWV, and TPR were highest in the extreme dipper group. No relationship was detected between hypertension subtypes and urinary sodium excretion.

  20. Effect of diet on excretion of estrogens in pre- and postmenopausal women.

    PubMed

    Goldin, B R; Adlercreutz, H; Dwyer, J T; Swenson, L; Warram, J H; Gorbach, S L

    1981-09-01

    Fecal, urinary, and plasma estrogens and plasma androgens were studied in healthy pre- and postmenopausal vegetarian and omnivorous women. Dietary histories of the subjects revealed that omnivores consumed a higher percentage of total protein and fat from animal sources. The total 72-hr fecal excretion as measured by dry weight was higher for vegetarians. Preliminary results indicate that vegetarian women excrete 2 to 3 times more estrogens in feces than do omnivores and that omnivores have about 50% higher mean plasma level of unconjugated estrone and estradiol than vegetarians. Estriol-3-glucuronide, a compound that is formed upon reabsorption of free estriol from the intestine, is found in lower concentrations in the urine of vegetarians. These data suggest that in vegetarians a greater amount of the biliary estrogens escape reabsorption and are excreted with the feces. The differences in estrogen metabolism may explain the lower incidence of breast cancer in vegetarian women.

  1. Tissue levels of (3(-14)C) coumarin in the rat: distribution and excretion.

    PubMed Central

    Piller, N. B.

    1977-01-01

    The benzo-pyrones (including coumarin) are a very effective therapy for mild thermal oedema and cases of acute and chronic lymphoedema. In this preliminary report the distribution of a single injected dose of coumarin was followed in normal tissues of rats for 100 hours. Comparisons are to be made later with drug levels in thermally injured and lymphoedematous tissues. The resluts show 7-4% of the injected dose to remain in the tissues after 100 h. During this time 30-9% was excreted in the faeces and approximately 47% excreted in the urine. At any given time most of the dose was present in the gut, muscular tissues, skin and liver. For the gut tissues this was 33%, for the muscular tissues 28%, for the skin 18% and for the liver 16%. The highest concentrations per gram of tissue were however in the kidney and liver, representing the two organs of metabolism and excretion of the coumarin. PMID:836764

  2. Benzo[a]pyrene metabolism and excretion in white suckers with chronic liver diseases

    SciTech Connect

    Smith, I.R.; Kirby, G.M.; Ferguson, H.W.; Hayes, M.A. )

    1993-05-01

    Wild white suckers (Catostomus commersoni) with diseased bile ducts excreted an oral dose of benzo[a]pyrene (BaP) into their bile as glucuronide, glutathione, and sulfo-conjugates at twice the rate of an unaffected reference population. BaP-hydroxylase (10% higher in the diseased population), glutathione-S-transferase (similar), or uridine-5[prime]-diphosphoglucuronic acid transferase (50% lower) levels did not correlate with these excretion rates. Metabolite levels were 57% higher in the liver of affected suckers than those in the liver of reference suckers, which might be due to bile retention within the diseased bile ducts. The bile duct disease affecting white suckers does not appear to restrict the metabolism and excretion of BaP.

  3. The effect of water loading on albumin excretion in type I diabetes mellitus.

    PubMed

    Wiegmann, T B; Chonko, A M; Herron, K; MacDougall, M L; Moore, W V

    1989-01-01

    An increased albumin excretion rate is recognized as an important early marker for incipient kidney disease in patients with diabetes mellitus. Many different techniques have been used, and a single void technique has been proposed as the simplest method for screening for increased albumin excretion. We evaluated a previous observation that single void samples during water diuresis yield increased albumin excretion rates. Timed day, night, and 24 hour albumin excretion rates (AER) were obtained in 35 patients with Type I diabetes mellitus. This was followed by examination of 8 consecutive half-hour specimens obtained during continued water diuresis. We compared 26 patients with low AER (less than 20 micrograms/min/24 hr sample) to 9 patients with high AER (greater than 20 and less than 200 micrograms/min/24 hr). Sampling began 60 min after the initiation of the waterload. At first, the AER in the low AER group was significantly higher than it was at night, but it decreased over 60 to 90 min of sampling to levels comparable with daytime AER. This was paralleled by a similar pattern in urine flow rate, sodium, and solute excretion. The AER in the high AER group did not increase with the water load and remained high throughout the study periods. The pattern of urine flow rate, sodium, and solute excretion was similar to that of the group with low AER. The study demonstrates that early sampling after water-induced diuresis leads to overestimation of AER in patients with low AER as compared to patients with high AER.(ABSTRACT TRUNCATED AT 250 WORDS)

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

    PubMed

    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

  5. Nitrogen excretion factors of livestock in the European Union: a review.

    PubMed

    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

  6. Excretion and ecotoxicity of pharmaceutical and personal care products in the environment.

    PubMed

    Jjemba, Patrick K

    2006-01-01

    The presence and fate of pharmaceutical and personal care products (PPCPs) in the environment is undergoing increasing scrutiny. The existing clinical pharmacokinetics and pharmacodynamics data for 81 common compounds were examined for cues of ecotoxicity. Of these the proportions excreted were available for 60 compounds (i.e., 74%). The compounds had a low (< or =0.5%), a moderately low (6-39%), a relatively high (40-69%), or a high (> or =70%) proportion of the parent compound excreted. More than half of the compounds evaluated have low or moderately low proportions of the parent compound excreted. However, the proportions excreted were negatively but moderately correlated (r = -0.50; n = 13; P = 0.08) with the concentrations of the compounds in the aquatic environment, suggesting that the compounds that have low proportions excreted may also have inherently low degradability in the environment. Solubility, logK(ow), and pKa work well in predicting the behavior of PPCPs under clinical conditions and have been used in the environmental assessment of PPCPs prior to approval. However, these parameters did not correlate with the proportion of PPCPs excreted in the environment or their concentration in the environment, underscoring the need for research into the behavior of PPCPs in the environment. PPCPs occur in low concentrations in the environment and are unlikely to elicit acute toxicity. An ecotoxicity potential that is based on chronic toxicity, bioavailability, and duration of exposure to nontarget organisms is described as a guide in assessing the potency of these compounds in the environment.

  7. Longitudinal Study of the Excretion Patterns of Thermophilic Campylobacter spp. in Young Pet Dogs in Denmark

    PubMed Central

    Hald, Birthe; Pedersen, Karl; Wainø, Michael; Jørgensen, Jens Christian; Madsen, Mogens

    2004-01-01

    The Campylobacter excretion patterns of 26 domestic pet dogs were described in a longitudinal study. The dogs entered the study between 3 and 8 months of age and were monitored until 2 years of age. They were tested monthly for Campylobacter carriage in stool samples that were cultured on the 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, 0.7% Campylobacter coli, and 2.8% Campylobacter spp. Isolates were typed by pulsed-field gel electrophoresis (PFGE) to elucidate the strain excretion pattern. All study dogs excreted Campylobacter spp. during the study period. At 3 months of age, 60% of the dogs carried Campylobacter, increasing to nearly 100% carriers at 1 year of age, whereafter the carriage rate decreased to 67% at 24 months of age. The PFGE types showed that individual dogs were often colonized by unique strains of C. upsaliensis for several months, up to 21 months or longer. These C. upsaliensis strains were either clonal (or underwent 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 spp. during the majority of their puppyhood and adolescent period. In general C. upsaliensis strains were excreted for months, with short-term interruptions by or cocolonization with other transitory Campylobacter spp., predominantly C. jejuni. C. jejuni was more prevalent in dogs between 3 months and 1 year of age than in dogs between 1 and 2 years of age. PMID:15131162

  8. Excretion of metabolites of prostacyclin and thromboxane by rats with nephrotoxic nephritis: effects of interleukin-1.

    PubMed Central

    Ward, P. S.; Fuller, R. W.; Ritter, J. M.; Cashman, S. J.; Rees, A. J.; Dollery, C. T.

    1991-01-01

    1. To obtain direct evidence of abnormal eicosanoid biosynthesis in rats injected with anti-glomerular-basement-membrane antibodies (a-GBM), products derived from thromboxane A2 (TXA2) and prostacyclin (PGI2) were measured in 24 h urine collections before and after a-GBM. 2. Administration of a-GBM (9.5 mg) caused albuminuria, decreased creatinine clearance, increased numbers of intra-glomerular neutrophils and increased excretion of TXB2, 2,3-dinor-TXB2 (products of TXA2) and 6-oxo-PGF 1 alpha and 2,3-dinor-6-oxo-PGF 1 alpha (products of PGI2) at 24 h. 3. Interleukin-1 (IL-1 beta; 5 micrograms) alone caused an increase in PGI2 metabolite excretion but had no effect on TXA2 metabolites. It had no effect on creatinine clearance but increased numbers of glomerular neutrophils by approximately 4-5 fold compared to a-GBM. 4. Pretreatment of rats with IL-1 beta before a-GBM synergistically increased albumin excretion but only additively increased eicosanoid excretion. Numbers of intra-glomerular neutrophils and creatinine clearance were unchanged compared to IL-1 beta alone. 5. The cyclo-oxygenase inhibitor, ibuprofen (10 mgkg-1 i.p., twice daily for 4 days) inhibited both serum TXB2 production and urinary prostaglandin excretion. It also caused an almost complete attenuation of albumin excretion. Creatinine clearance and glomerular neutrophils remained unchanged after a-GBM/IL-1 beta. 6. We conclude that the 50% inhibition of thromboxane production induced by ibuprofen does not modify the fall in creatinine clearance of accumulation of neutrophils in the glomerulus caused by the a-GBM. This degree of inhibition of eicosanoid production was associated with a striking decrease in proteinuria, but this may reflect a haemodynamic rather than a disease modifying action. PMID:1933130

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

    PubMed Central

    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 fructose, respectively. While the correlation between the two methods was good for fructose (Pearson correlation 0.71), the correlation was weak for sucrose (Pearson correlation 0.27). We favor the GC method due to its better sensitivity, simplicity, and the ability to quantify fructose and sucrose directly in the same run. Of the 106 samples from 53 participants with complete urine collection after two study diets, 24-hour urinary fructose excretion was significantly associated with fructose intake. The sum of 24-hour urinary fructose and sucrose was significantly associated with total sugars consumption. However, variation in intakes of sugars explained only a modest amount of variation in urinary sugars excretion. In the unadjusted models, fructose intake explained 24.3% of urinary fructose excretion; and intake of total sugars 16.3% of the sum of urinary fructose and sucrose. The adjusted models explained 44.3% of urinary fructose excretion and 41.7% of the sum of urinary fructose and sucrose. Therefore, we caution using these biomarkers to predict sugars consumption before other factors that determine urinary sugars excretion are understood. PMID:24034568

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

    PubMed

    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

  11. A membrane vesicle-based assay to enable prediction of human biliary excretion.

    PubMed

    Colombo, Federico; Poirier, Hugo; Rioux, Nathalie; Montecillo, Maria Arias; Duan, Jianmin; Ribadeneira, Maria D

    2013-10-01

    1. Prediction of biliary excretion is a challenge due to the lack of in vitro assays. Our laboratory previously demonstrated a highly significant correlation between in vitro IC50 values against mrp2 using rat canalicular liver plasma membrane vesicles and in vivo biliary excretion (Colombo et al., 2012). This study explores the possibility of predicting in vivo biliary excretion in human using membrane vesicles prepared from MDCKII cells transfected with human ABCC2. 2. In vitro MRP2 activity was determined by measuring the ATP-dependent uptake of 5(6)-carboxy-2',7'-dichlorofluorescein (CDCF) in inside-out membrane vesicles isolated from MDCK-ABCC2 cells. CDCF uptake was time- and concentration-dependent (Km of 4.0 ± 1.2 µM and a Vmax of 7.8 ± 0.9 pmol/mg/min) and inhibited by benzbromarone and MK-571 with IC50 values of 1.2 and 7.6 µM, respectively. 3. A significant linear correlation (r(2 )= 0.790) between the in vitro IC50 values from the described MRP2 assay and in vivo biliary excretion in humans was observed using 11 well-documented drugs covering low to high biliary excretions. 4. This study demonstrates, for the first time, that inhibition of CDCF uptake in MDCKII-ABCC2 vesicles not only provides a screening assay to assess MRP2 drug-drug interaction potential, but is also predictive of human MRP2-mediated biliary excretion.

  12. Sex and age differences in mercury distribution and excretion in methylmercury-administered mice

    SciTech Connect

    Hirayama, K.; Yasutake, A.

    1986-01-01

    Sex differences in mercury distribution and excretion after single administration of methylmercury chloride (MMC, 5 mg/kg were studied in mice. A sex difference in urinary mercury excretion was found in sexually mature mice (age of 7 wk) of C57BL/6N and BALB/cA strains. Males showed higher mercury levels in urine than females, though no significant difference was found in fecal mercury levels 24 h post exposure to MMC. The higher urinary excretion rates in males accounted for significant lowering of mercury levels in the brain, liver, and blood, but not in the kidney, which showed higher values. At 5 min, however, the sex difference was found only in the kidney, showing higher levels in males. Changes in mercury distribution with time were studied in C57BL/6N mice. The brain mercury increased in both sexes up to 3 d, and decreased only in males on d 5. Liver and blood mercury decreased with time in both sexes, and these were constantly higher in females than in males. Renal mercury in males decreased to similar levels to females on d 3. The sex differences at various ages were studied with C57BL/6N mice 24 h after dosing. Two-week-old mice did not show significant sex differences in the mercury distribution and excretion, and their urinary mercury levels were much lower as compared to the older mice. Urinary mercury excretion in both sexes increased at 4 wk of age and then decreased at 45 wk of age. At 4, 7, 10, and 45 wk of age, males showed higher urinary mercury levels than females. From these findings, it has been suggested that urinary mercury excretion may be related to sex hormones, especially androgens.

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

    PubMed

    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 < 0.01, respectively) and moist ( < 0.01) foods. For LAL, no significant relationship was observed. Urinary recovery (% ingested) showed a negative relationship with daily intake for FL, CML, and LAL in the dry foods ( < 0.01, < 0.01, and = 0.08, respectively) and for CML and LAL in the moist foods ( < 0.01). The observed increase in urinary excretion with increasing dietary intake indicates that dietary 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

  14. Effect of metal chelators on excretion and tissue levels of essential trace elements

    SciTech Connect

    Tandon, S.K.; Jain, V.K.; Mathur, A.K.

    1984-10-01

    The influence of one, three, and six doses of ethylenediaminetetraacetic acid (EDTA) diethylenetriaminepentaacetic acid (DTPA), and triethylenetetramine (TETA) on the urinary excretion of Ca, Cu, Fe, and Zn, and on their levels in liver, kidneys, heart, and serum in rats, was investigated to ascertain their suitability in amelioration of metal intoxication. While excretion of all the essential trace metals examined was enhanced significantly, the tissue and serum levels of some of them either increased or decreased after administration of the chelators. The results suggest depletion of some of the endogenous trace metals from the body and their intertissue redistribution following treatment with these chelating agents.

  15. Amylase: creatinine clearance ratio and urinary excretion of lysozyme in acute pancreatitis and acute duodenal perforation.

    PubMed

    Berger, G M; Cowlin, J; Turner, T J

    1976-09-18

    The amylase:creatinine clearance ratio in patients suffering from acute pancreatitis or acute duodenal perforation was higher than normal in both groups of patients. These findings cast doubt on the value of this parameter as a specific index of acute pancreatitis. The mechanism or mechanisms underlying the increased amylase excretion have not been determined. However, the markedly elevated urinary excretion of lysozyme observed in some patients suggests, by analogy, that diminished tubular reabsorption of amylase may contribute towards the elevated amylase:creatinine ratio.

  16. Consumption of sesame oil muffins decreases the urinary excretion of gamma-tocopherol metabolites in humans.

    PubMed

    Frank, Jan; Kamal-Eldin, Afaf; Traber, Maret G

    2004-12-01

    Sesame seed and oil consumption previously increased human plasma gamma-tocopherol (gamma-T) concentrations. This was attributed to the sesame lignans sesamin and sesamolin. Here, we studied the inhibition of vitamin E metabolism by a single dose of sesame oil lignans coingested with deuterated alpha- and gamma-tocopherols in human volunteers. The urinary excretion of gamma-T metabolites was significantly lower in sesame oil treated than in control subjects. Concentrations of tocopherols in blood were not affected by the treatment. In conclusion, a single dose of sesame oil, containing 136 mg sesame lignans (sesamin and sesamolin), reduces the urinary excretion of co-administered gamma-T in humans.

  17. Assessment of urinary excretion of antimalarial drugs in large-scale chemotherapeutic eradication projects

    PubMed Central

    Bruce-Chwatt, L. J.

    1959-01-01

    Assessment of the urinary excretion of an antimalarial drug is a useful means of checking the amount of drug administered and the regularity of intake. The author describes the various methods available for the qualitative and quantitative estimation of antimalarial drugs in urine and discusses their relative merits, with special reference to their suitability for use in the field. He points out the difficulties involved in estimating the urinary excretion of antimalarials in large-scale chemotherapeutic eradication projects and stress the importance of simplifying testing techniques as far as possible. PMID:13805135

  18. Neurogenic hypertension associated with an excessively high excretion rate of catecholamine metabolites.

    PubMed Central

    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 likely to be caused by the syndrome of raised catecholamines after cerebrovascular accidents than a phaeochromocytoma. A phaeochromocytoma should not be diagnosed within several months of cerebral infarction without first excluding the possibility of a hyperadrenergic state induced by cerebral infarction. PMID:3593621

  19. Refining the excretion factors of methadone and codeine for wastewater analysis - Combining data from pharmacokinetic and wastewater studies.

    PubMed

    Thai, Phong K; Lai, Foon Yin; Bruno, Raimondo; van Dyken, Emma; Hall, Wayne; O'Brien, Jake; Prichard, Jeremy; Mueller, Jochen F

    2016-09-01

    Analysing drug residues in wastewater (wastewater analysis) to monitor the consumption of those drugs in the population has become a complementary method to epidemiological surveys. In this method, the excretion factor of a drug (or the percentage of drug metabolites excreted through urine) is a critical parameter for the back-estimation of the consumption of a drug. However, this parameter is usually derived from a small database of human pharmacokinetic studies. This is true for methadone and codeine, the two most commonly used opioids and also common substances of abuse. Therefore, we aimed to refine the current excretion factors used for estimating methadone and codeine by analysing published data from the literature on the excretion of methadone, its main metabolite, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), and codeine. Our review included both human drug pharmacokinetic studies and wastewater analysis studies. We found that while the commonly used excretion factor of methadone (~27.5%) was relatively accurate, the excretion factor of EDDP, a better biomarker for methadone consumption in sewer epidemiology, should be twice that of methadone (i.e. 55%) instead of the current equal or half values. For codeine, the excretion factor should be ~30% instead of 63.5% or 10% as previously used in wastewater analysis studies. Data from wastewater analysis studies could be used in this way to refine the excretion factors of the drugs of interest. PMID:27295047

  20. Methods to Evaluate Biliary Excretion of Drugs in Humans: an Updated Review

    PubMed Central

    Ghibellini, Giulia; Leslie, Elaine M.; Brouwer, Kim L.R.

    2008-01-01

    Determining the biliary clearance of drugs in humans is very challenging because bile in not readily accessible due to the anatomy of the hepatobiliary tract. The collection of bile usually is limited to post-surgical patients with underlying hepatobiliary disease. In healthy subjects, feces typically are used as a surrogate to quantify the amount of drug excreted via non-urinary pathways. Nevertheless, it is very important to characterize hepatobiliary elimination because this is a potential site of drug interactions that might result in significant alterations in systemic or hepatic exposure. In addition to the determination of in vivo biliary clearance values of drugs, the availability of in vitro models that can predict the extent of biliary excretion of drugs in humans may be a powerful tool in the pre-clinical stages of drug development. In this review, recent advances in the most commonly used in vivo methods to estimate biliary excretion of drugs in humans are outlined. Additionally, in vitro models that can be employed to investigate the molecular processes involved in biliary excretion are discussed to present an updated picture of the new tools and techniques that are available to study the complex processes involved in hepatic drug transport. PMID:16749853

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

    SciTech Connect

    Koch, Iris; Sylvester, Steven; Lai, Vivian W.-M.; Owen, Andrew; Reimer, Kenneth J. Cullen, William R.

    2007-08-01

    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.

  2. Feed management practices to reduce manure phosphorus excretion in dairy cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus (P) is an essential mineral that needs to be supplied in sufficient quantities for maintenance and growth and milk production in dairy cattle. However, over 60% of the P consumed can be excreted in faeces with a potential to cause environmental pollution. Concern over higher levels of P i...

  3. [Studies on distribution and excretion of squalane in dogs administered for 2 weeks].

    PubMed

    Kamimura, H; Fuchigami, K; Inoue, H; Kodama, R; Yoshimura, H

    1991-05-01

    In the previous papers, we demonstrated, by using rats, that squalane (2,6,10,15,19, 23-hexamethyltetracosane) could stimulate the fecal excretion of 2,3,4,7,8-pentachlorodibenzofuran, the most important etiologic agent of Yusho, which was accumulated in the body of rat. We also reported that, in rats and dogs, squalane did not show any appreciable toxic signs during 3-month treatment, though a part of squalane was absorbed from gastrointestinal tract of dogs. In the present paper, we have investigated the elimination of absorbed squalane in beagle dogs. During the treatment with squalane orally at a dose of 1200 mg/kg/day for 14 days, the fecal excretion of squalane per day was 65-90% of the daily dose. After the treatment (on the day 14), squalane levels in blood and hair were about 30 ppm and 14640 ppm, respectively. On the day 56 after the first dosing, squalane was not detected in blood. On the day 70, squalane level in hair was reduced to about 1% of that on the day 14. Squalane levels in skin, liver, adipose tissue and small intestine on the day 70 were also reduced compared with that on the day 42. Moreover, small amount of squalane was still excreted into feces from the day 15 to the day 70. These results suggested that absorbed squalane was gradually excreted through feces and skin in dogs.

  4. Organic Anion Transporter 5 Renal Expression and Urinary Excretion in Rats with Vascular Calcification

    PubMed Central

    Hazelhoff, María Herminia; Bulacio, Romina Paula; Torres, Adriana Mónica

    2013-01-01

    It has been described renal damage in rats with vascular calcification. The organic anion transporter 5 (Oat5) is only expressed in kidney, and its urinary excretion was proposed as potential early biomarker of renal injury. The aim of this study was to evaluate the Oat5 renal expression and its urinary excretion in an experimental model of vascular calcification in comparison with traditional markers of renal injury. Vascular calcification was obtained by the administration of an overdose of vitamin D3 (300,000 IU/kg, b.w., i.m.) to male Wistar rats. Oat5 urinary abundance was evaluated by Western blotting. Traditional markers of renal injury, such as creatinine and urea plasma levels, urinary protein levels, and urinary alkaline phosphatase (AP) activity, were determined using commercial kits. Histology was assessed by hematoxylin/eosin staining. Oat5 renal expression was evaluated by Western blotting and by immunohistochemistry. An increased expression of Oat5 in renal homogenates, in apical membranes, and in its urinary excretion was observed in rats with vascular calcification. The traditional parameters used to evaluate renal function were not modified, with the exception of histology. It is possible to postulate the urinary excretion of Oat5 as a potential noninvasive biomarker of renal injury associated with vascular calcification. PMID:24199190

  5. Urinary folate excretion in chronic ethanol- and diet-treated rats

    SciTech Connect

    Collins, T.D.; McMartin, K.E.; Bairnsfather, L.

    1986-03-05

    Acute ethanol treatment of rats produces a marked increase in urinary folate excretion, which accumulates in correlation with the duration of ethanol treatment. In order to study the role of excess urinary folate excretion in the development of folate deficiency by chronic ethanol feeding, groups of male Sprague-Dawley rats were maintained for four months on one of the following liquid diets: ethanol, pair-fed control, ethanol minus folic acid, and pair-fed control minus folic acid. A fifth group was provided a control chow diet ad libitum. Blood ethanol levels were generally maintained between 80-150 mg/dl at various times of the day. Decrease in plasma and tissue folate levels occurred within four weeks in all liquid diet groups compared to chow rats and within two weeks for urinary folate levels. Greater effects were generally observed in both folate-deficient groups than in the control or ethanol group. Acute ethanol treatment of rats from the various diet groups produced increases in urinary folate excretion in all groups except the ethanol minus folic acid diet group. When the folate system of rats are compromised by dietary deprivation and/or chronic ethanol treatment, these results suggest that urinary folate excretion is greatly reduced as a conservation measure.

  6. Surface charge-mediated rapid hepatobiliary excretion of mesoporous silica nanoparticles.

    PubMed

    Souris, Jeffrey S; Lee, Chia-Hung; Cheng, Shih-Hsun; Chen, Chin-Tu; Yang, Chung-Shi; Ho, Ja-an A; Mou, Chung-Yuan; Lo, Leu-Wei

    2010-07-01

    Nanoparticle-assisted drug delivery has been emerging as an active research area in recent years. The in vivo biodistribution of nanoparticle and its following mechanisms of biodegradation and/or excretion determine the feasibility and applicability of such a nano-delivery platform in the practical clinical translation. In this work we report the synthesis of the highly positive charge, near-infrared fluorescent mesoporous silica nanoparticles (MSNs) that demonstrate rapid hepatobiliary excretion, for use as traceable drug delivery platforms of high capacity. MSNs were incorporated with near-infrared fluorescent dye indocyanine green (ICG) via covalent or ionic bonding, to derive comparable constructs of significantly different net surface charge. In vivo fluorescence imaging and subsequent inductively coupled plasma-mass spectroscopy of harvested tissues, urine, and feces revealed markedly different uptake and elimination behaviors between the two conjugations; with more highly charged moieties (+34.4 mV at pH 7.4) being quickly excreted from the liver into the gastrointestinal tract, while less charged moieties (-17.6 mV at pH 7.4) remained sequestered within the liver. Taken together, these findings suggest that charge-dependent adsorption of serum proteins greatly facilitates the hepatobiliary excretion of silica nanoparticles, and that nanoparticle residence time in vivo can be regulated by manipulation of surface charge.

  7. NHANES Data Support Link between Handling of Thermal Paper Receipts and Increased Urinary Bisphenol A Excretion.

    PubMed

    Hehn, Rebecca Simonne

    2016-01-01

    Some thermal paper receipts, commonly referred to as cash register receipts, contain high levels of bisphenol A (BPA). The goal of this study is to investigate whether increased contact with thermal paper receipts is associated with an increase in urinary BPA excretion. Individuals from the NHANES 2003-2004 survey were stratified based on occupation to compare urinary BPA excretion levels. The first major finding demonstrates that individuals with potential occupational exposure to thermal paper receipts are more likely to have detectable levels of urinary BPA compared to individuals with unlikely occupational exposure (p-value <0.001). The second major finding is that females with potential occupational exposure to thermal paper receipts have significantly higher levels of urinary BPA excretion (geometric mean (GM): 5.45 μg/L, 95% CI: (4.02, 7.39)) compared to females with unlikely occupational exposure (GM: 2.16 μg/L, 95% CI: (1.73, 2.70)). This association continues to remain statistically significant when controlling for creatinine, race, body mass index (BMI), and age. Notably, there was no statistically significant association between occupation and urinary BPA excretion among males. These results suggest that exposure to BPA from thermal paper should be considered when determining aggregate BPA exposure. PMID:26583963

  8. Aflatoxin excretion in children with kwashiorkor or marasmic kwashiorkor--a clinical investigation.

    PubMed

    de Vries, H R; Maxwell, S M; Hendrickse, R G

    1990-04-01

    A group of five children with kwashiorkor, seven with marasmic kwashiorkor and one underweight child were given an aflatoxin-free diet consisting of maize meal and milk powder. Blood specimens were collected on admission; on day 4 and 10, 24 hour urine and stool samples were collected for the first ten days. Serum, urine and stool samples were analysed for aflatoxins using high performance liquid chromatography with fluorescent detection, after various extraction and clean-up procedures. The children with kwashiorkor and marasmic kwashiorkor excreted aflatoxins in stools for up to 9 and 6 days after admission respectively. No aflatoxins were detected in the stools or urine of the underweight child. In kwashiorkor, urinary excretion ceased after 2 days, while in marasmic kwashiorkor urinary excretion persisted for 4 days. In stools, B1 was the type of aflatoxin detected most frequently in kwashiorkor and least frequently in marasmic kwashiorkor. Aflatoxin M2 was frequently detected in the stools of both groups of children. Estimates of the total amount of aflatoxin excreted by kwashiorkor and marasmic kwashiorkor indicate that these children were harbouring up to 4 micrograms/kg body weight at the time of admission. These findings establish that aflatoxins accumulate in body fluids and tissues in kwashiorkor and marasmic kwashiorkor which is only slowly eliminated.

  9. 10 CFR 35.190 - Training for uptake, dilution, and excretion studies.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Training for uptake, dilution, and excretion studies. 35.190 Section 35.190 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Unsealed...) Mathematics pertaining to the use and measurement of radioactivity; (D) Chemistry of byproduct material...

  10. 10 CFR 35.190 - Training for uptake, dilution, and excretion studies.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Training for uptake, dilution, and excretion studies. 35.190 Section 35.190 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Unsealed...) Mathematics pertaining to the use and measurement of radioactivity; (D) Chemistry of byproduct material...

  11. 10 CFR 35.190 - Training for uptake, dilution, and excretion studies.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Training for uptake, dilution, and excretion studies. 35.190 Section 35.190 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Unsealed...) Mathematics pertaining to the use and measurement of radioactivity; (D) Chemistry of byproduct material...

  12. EFFECT OF DOSE ON THE EXCRETION AND METABOLISM OF MONOMETHYLARSONIC ACID IN THE MOUSE

    EPA Science Inventory

    EFFECT OF DOSE ON THE EXCRETION AND METABOLISM OF MONOMETHYLARSONIC ACID IN THE MOUSE
    M F Hughes1, V Devesa2, B C Edwards1, C T Mitchell1, E M Kenyon1, and D J Thomas1. 1US EPA, ORD, NHEERL, ETD, Research Triangle Park, NC; 2UNC-CH, CEMALB, Chapel Hill, NC

    Monomethylar...

  13. Chronic cadmium intake results in dose-related excretion of metallothionein in urine.

    PubMed

    Shaikh, Z A; Harnett, K M; Perlin, S A; Huang, P C

    1989-02-15

    Urinary excretion of metallothionein was measured by radioimmunoassay in rats given drinking water containing 5 or 50 mg cadmium/l for up to 2 years. The metallothionein levels corresponded to the concentration of cadmium in the drinking water and increased linearly over the course of the study. These results demonstrate that urinary metallothionein is a sensitive biological indicator of oral cadmium exposure.

  14. Protein turnover and 3-methylhistidine excretion in non-pregnant, pregnant and gestational diabetic women

    SciTech Connect

    Fitch, W.L.; King, J.C.

    1986-03-01

    Protein turnover was studied in nine non-pregnant (NP) women, eight pregnant (P) and two gestational diabetic (GDM) women. Whole body protein turnover, synthesis and catabolism rates were measured using a single oral dose of /sup 15/N-glycine followed by measurement of enrichment of urinary ammonia. Urinary 3-methylhistidine (3MH) excretion was measured for three consecutive days, including the day of the protein turnover study. Whole body protein turnover and synthesis rates did not differ between the P and NP women, although the synthesis rates tended to be higher in the P group. Gestational diabetic women appeared to have considerably higher rates of both turnover and synthesis. Pregnant women excreted significantly more urinary 3MH than did non-pregnant women. GDM women appeared to have lower 3MH excretion than the P women. Correlation between 3MH excretion and protein turnover rates was nearly significant (p = .06) in the NP women, but was poorly correlated (p = .43) in the P women, suggesting that muscles may be a less important site of whole body protein turnover in pregnancy than in the non-pregnant state.

  15. Influence of oral metronidazole on the endocrine milieu and sebum excretion rate.

    PubMed

    Aizawa, H; Niimura, M; Kon, Y

    1992-12-01

    As part of a study of the mechanism of metronidazole's efficacy in the treatment of acne and rosacea, its effects on the endocrine milieu and sebum excretion rate were assessed. Thirteen healthy males received oral metronidazole treatment (500 mg/day) for 4 weeks. Serum sex hormone levels were determined in all 13 subjects and the sebum excretion rate was determined in seven of them, before and after treatment. We measured serum levels of estrone (E1), estradiol (E2), total testosterone (T), free testosterone (FT), dihydrotestosterone (DHT), dehydroepiandrosterone sulfate (DHEA-S), and sex hormone-binding globulin (SHBG). There were no significant changes in E1, T, FT, DHT, or SHBG levels, but E2 and DHEA-S levels decreased significantly after treatment. In all seven subjects in whom the sebum excretion rates were determined, the amount of facial skin surface lipids decreased significantly after treatment. These results suggest that metronidazole exerts its clinical effects through suppressing the sebum excretion by a mechanism other than anti-androgenic action. PMID:1293188

  16. NHANES Data Support Link between Handling of Thermal Paper Receipts and Increased Urinary Bisphenol A Excretion.

    PubMed

    Hehn, Rebecca Simonne

    2016-01-01

    Some thermal paper receipts, commonly referred to as cash register receipts, contain high levels of bisphenol A (BPA). The goal of this study is to investigate whether increased contact with thermal paper receipts is associated with an increase in urinary BPA excretion. Individuals from the NHANES 2003-2004 survey were stratified based on occupation to compare urinary BPA excretion levels. The first major finding demonstrates that individuals with potential occupational exposure to thermal paper receipts are more likely to have detectable levels of urinary BPA compared to individuals with unlikely occupational exposure (p-value <0.001). The second major finding is that females with potential occupational exposure to thermal paper receipts have significantly higher levels of urinary BPA excretion (geometric mean (GM): 5.45 μg/L, 95% CI: (4.02, 7.39)) compared to females with unlikely occupational exposure (GM: 2.16 μg/L, 95% CI: (1.73, 2.70)). This association continues to remain statistically significant when controlling for creatinine, race, body mass index (BMI), and age. Notably, there was no statistically significant association between occupation and urinary BPA excretion among males. These results suggest that exposure to BPA from thermal paper should be considered when determining aggregate BPA exposure.

  17. Corticosterone excretion patterns and affiliative behavior over development in ravens (Corvus corax)

    PubMed Central

    Stöwe, Mareike; Bugnyar, Thomas; Schloegl, Christian; Heinrich, Bernd; Kotrschal, Kurt; Möstl, Erich

    2015-01-01

    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 independent from their parents (September–November). We related these corticosterone excretion patterns to socio-positive behavior. Behavioral data were collected via focal sampling in each developmental period considered. We analyzed amounts of excreted immunoreactive corticosterone metabolites (CM) using enzyme immuno assays. We collected fecal samples in each developmental period considered and evaluated the most appropriate assay via an isolation stress experiment. Basal CM was significantly higher during the nestling period than post-fledging or when birds were independent. The time nestlings spent allopreening correlated negatively with mean CM. Post-fledging, individuals with higher CM levels sat close to (distance <50 cm) conspecifics more frequently and tended to preen them longer. When birds were independent and a stable rank hierarchy was established, dominant individuals were preened significantly longer than subordinates. These patterns observed in ravens parallel those described for primates, which could indicate that animal species living in a complex social environment may deal with social problems in a similar way that is not restricted to mammals or primates. PMID:18022623

  18. Cultivable alginate lyase-excreting bacteria associated with the Arctic brown alga Laminaria.

    PubMed

    Dong, Sheng; Yang, Jie; Zhang, Xi-Ying; Shi, Mei; Song, Xiao-Yan; Chen, Xiu-Lan; Zhang, Yu-Zhong

    2012-11-01

    Although some alginate lyases have been isolated from marine bacteria, alginate lyases-excreting bacteria from the Arctic alga have not yet been investigated. Here, the diversity of the bacteria associated with the brown alga Laminaria from the Arctic Ocean was investigated for the first time. Sixty five strains belonging to nine genera were recovered from six Laminaria samples, in which Psychrobacter (33/65), Psychromonas (10/65) and Polaribacter (8/65) were the predominant groups. Moreover, 21 alginate lyase-excreting strains were further screened from these Laminaria-associated bacteria. These alginate lyase-excreting strains belong to five genera. Psychromonas (8/21), Psedoalteromonas (6/21) and Polaribacter (4/21) are the predominant genera, and Psychrobacter, Winogradskyella, Psychromonas and Polaribacter were first found to produce alginate lyases. The optimal temperatures for the growth and algiante lyase production of many strains were as low as 10–20 °C, indicating that they are psychrophilic bacteria. The alginate lyases produced by 11 strains showed the highest activity at 20–30 °C, indicating that these enzymes are cold-adapted enzymes. Some strians showed high levels of extracellular alginate lyase activity around 200 U/mL. These results suggest that these algiante lyase-excreting bacteria from the Arctic alga are good materials for studying bacterial cold-adapted alginate lyases. PMID:23203272

  19. Effect of dietary fat on the fecal excretion of cholesterol and its degradation products in man

    PubMed Central

    Moore, Richard B.; Anderson, Joseph T.; Taylor, Henry L.; Keys, Ancel; Frantz, Ivan D.

    1968-01-01

    Fecal bile acid and neutral sterol excretion rates were determined in five healthy young men when serum cholesterol changes were induced by isocaloric substitution of an unsaturated (safflower oil) for a saturated fat (butter). The isotope balance method was used after the intravenous injection of cholesterol-4-14C. A feces extraction method is presented which permits essentially complete separation of fecal neutral sterols and bile acids. There was a significant increase in the total excretion of the fecal end products of cholesterol metabolism from 966 ± 42 mg/day on saturated fat to 1147 ± 45 mg/day on unsaturated fat, and the increase was equally distributed between the neutral sterol and bile acid fractions. With the substitution of dietary fats, regardless of the sequence of their feeding, there was a 28% reduction in serum cholesterol concentration during ingestion of the unsaturated fat. There were reciprocal changes in serum cholesterol levels and fecal steroid excretion with the substitution of one type of fat for the other. The changes in plasma cholesterol content were more than adequately balanced by the reciprocal changes in fecal cholesterol end product excretion. The findings in this study agree with several previous reports in supporting the hypothesis that the hypocholesteremic action of dietary unsaturated fatty acids is associated with an increase in the fecal loss of bile acids and neutral sterols. PMID:5658585

  20. Daily uranium excretion in German peacekeeping personnel serving on the Balkans compared to ICRP model prediction.

    PubMed

    Oeh, U; Li, W B; Höllriegl, V; Giussani, A; Schramel, P; Roth, P; Paretzke, H G

    2007-01-01

    An investigation was performed to assess a possible health risk of depleted uranium (DU) for residents and German peacekeeping personnel serving on the Balkans. In order to evaluate a possible DU intake, the urinary uranium excretions of volunteers were collected and analysed using inductively coupled plasma mass spectrometry (ICP-MS). In total, more than 1300 urine samples from soldiers, civil servants and unexposed controls of different genders and ages were analysed to determine uranium excretion parameters. All participating volunteers, aged 3-92 y, were grouped according to their gender and age for evaluation. The results of the investigation revealed no significant difference between the unexposed controls and the peacekeeping personnel. In addition, the geometric means of the daily urinary excretion in peacekeeping personnel, ranging from 3 to 23 ng d(-1) for different age groups, fall toward the lower end of renal uranium excretion values published for unexposed populations in literature. The measured data were compared with the International Commission on Radiological Protection prediction for the intake of natural uranium by unexposed members of the public. The two data sets are in good agreement, indicating that no relevant intake of additional uranium, either natural or DU, has appeared for German peacekeeping personnel serving on the Balkans. PMID:17567762

  1. Approaches for the identification of potential excreted/secreted proteins of Leishmania major parasites.

    PubMed

    Chenik, M; Lakhal, S; Ben Khalef, N; Zribi, L; Louzir, H; Dellagi, K

    2006-04-01

    Leishmania parasites are able to survive in host macrophages despite the harsh phagolysosomal vacuoles conditions. This could reflect, in part, their capacity to secrete proteins that may play an essential role in the establishment of infection and serve as targets for cellular immune responses. To characterize Leishmania major proteins excreted/secreted early after promastigote entry into the host macrophage, we have generated antibodies against culture supernatants of stationary-phase promastigotes collected 6 h after incubation in conditions that partially reproduce those prevailing in the parasitophorous vacuole. The screening of an L. major cDNA library with these antibodies led us to isolate 33 different cDNA clones that we report here. Sequence analysis revealed that the corresponding proteins could be classified in 3 groups: 9 proteins have been previously described as excreted/secreted in Leishmania and/or other species; 11 correspond to known proteins already characterized in Leishmania and/or other species although it is unknown whether they are excreted/secreted and 13 code for unknown proteins. Interestingly, the latter are transcribed as shown by RT-PCR and some of them are stage regulated. The L. major excreted/secreted proteins may constitute putative virulence factors, vaccine candidates and/or new drug targets.

  2. Increased urinary excretion of platelet activating factor in mice with lupus nephritis

    SciTech Connect

    Macconi, D.; Noris, M.; Benfenati, E.; Quaglia, R.; Pagliarino, G. ); Remuzzi, G. Ospedali Riuniti di Bergamo )

    1991-01-01

    Platelet activating factor (PAF) is present in urine from humans and experimental animals in normal conditions. Very little is known about changes in PAF urinary excretion under pathologic conditions and no data are available about the origin of PAF in the urine. In the present study we explored the possibility that immunologic renal disease is associated with an increase in PAF urinary excretion using gas chromatography-mass spectrometry technique. To clarify the renal or extrarenal origin of urinary PAF we evaluated whether exogenously administered PAF (1-(1{prime},2{prime}-{sup 3}H)alkyl) is filtered through the glomerulus and excreted in the urine. The results show that: (1) urine from mice with lupus nephritis in the early phase of the disease contained amounts of PAF comparable to those excreted in normal mouse urine, (2) PAF levels increased when animals started to develop high grade proteinuria, (3) after intravenous injection of ({sup 3}H) PAF In nephritic mice, a negligible amount of ({sup 3}H) ether lipid, corresponding to ({sup 3}H)1-alkyl -2-acyl-3-phosphocholine (alkyl-2-acyl-GPC), was recovered from the 24 h urine extract.

  3. Study of the Assessment Method for N Excretion in Sustainable Heavy Pigs Production

    NASA Astrophysics Data System (ADS)

    Guo, Kaijun; Liu, Fenghua; Xu, Xiaolong; Xu, Jianqin; Zoccarato, Ivo

    Italian heavy pigs, with an average slaughtering body weight of 150-170 kg, are world-wide famous for its Parma ham production. Because the requirement of market diversity, producers are interested in ham production following the procedure of Italian pork industry. However, with ever growing public concern about nitrogen (N) pollution in the environment, it is necessary to determine a suitable method to measure N excretion from heavy pig production. The N retention was calculated by factorial method and compared with estimations of other methods available in literature. The results showed that the N percentage of heavy pigs is 2.43% ± 0.07% on body weight basis and the percentage of N excretion was approximately 69.62% ± 0.20 of N intake. Regarding the N excretion of estimation methods, the proposal of Xiccato et al. was closer to reality of the heavy pig production than other methods and could be used as a standard way to calculate the N excretion. Besides the overall standard, it is opportune to make a N balance sheet for every individual farm under specific conditions. Only in this way, the farmers can realize their deficiencies and will voluntarily follow the Good Management Practice (GMP) indications so as to guarantee a sustainable development of pig production.

  4. Afferent pathways of neural reno-renal reflexes controlling sodium and water excretion in the cat.

    PubMed

    Golin, R; Genovesi, S; Stella, A; Zanchetti, A

    1987-08-01

    We have studied the role of afferent renal nerve fibres in anaesthetized cats in mediating the decrease in sodium and water excretion from the contralateral kidney caused by unilateral renal denervation. Transient denervation of one kidney obtained by cooling of the left renal nerves increases contralateral efferent renal nerve activity and decreased sodium and water excretion from the opposite kidney. The results observed in animals with intact neural pathways were compared with those obtained after the left kidney had been selectively deafferentated by cutting the dorsal roots from T9 to L4. Bilateral section of dorsal roots did not affect the increase in sodium and water excretion from the transiently denervated left kidney, but entirely abolished the decrease in sodium and water excretion from the contralateral kidney. Neither the left nor the right dorsal root section alone, affected the response of the contralateral right kidney. Our data demonstrate that afferent renal nerve fibres project bilaterally to the spinal cord and form the afferent branch of the reno-renal reflex by which one kidney can control the function of the opposite one.

  5. Uptake and excretion of ( UC)methyl bromide as influenced by exposure concentration

    SciTech Connect

    Medinsky, M.A.; Dutcher, J.S.; Bond, J.A.; Henderson, R.F.; Mauderly, J.L.; Snipes, M.B.; Mewhinney, J.A.; Cheng, Y.S.; Birnbaum, L.S.

    1985-01-01

    Uptake of methyl bromide and pathways for excretion of UC were investigated in male Fischer-344 rats after nose-only inhalation of 50, 300, 5700, or 10,400 nmol (1.6 to 310 ppm) of ( UC)methyl bromide/liter of air for 6 hr. Fractional uptake of methyl bromide decreased at the highest concentrations, 5700 and 10,400 nmol/liter, with 37 and 27% of the inhaled methyl bromide absorbed, respectively, compared to 48% at the lower levels. Total methyl bromide absorbed was 9 or 40 mol/kg body wt after exposure to 50 or 300 nmol/liter, respectively. Elimination of UC was linearly related to the amount of methyl bromide absorbed as determined from urine, feces, expired CO2, and parent compound collected for 66 hr after the end of exposure. Exhaled UCO2 was the dominant route of excretion, with from 1.2 to 110 mol (50% of amount absorbed) exhaled, and was described by a two-component negative exponential function; 85% was exhaled with t1/2 of 4 hr, and the remaining 15% was exhaled with a t1/2 of 17 hr. The rate of exhalation of UCO2 was not affected by the amount of ( UC)methyl bromide absorbed. From 0.4 to 54 mol was excreted in urine (20% of amount absorbed). The half-time for excretion of UC in urine was approximately 10 hr, and the rate of excretion was not dependent on the amount of ( UC)methyl bromide absorbed. Little UC was exhaled as methyl bromide (<4% of the dose) or excreted in feces (<2%). At the end of 66 hr, 25% of the UC absorbed remained in the rats. Liver, kidneys, adrenals, lungs, thymus, and turbinates (maxilloturbinates, ethmoturbinates, and nasal epithelial membrane) contained the highest concentrations of UC. Results indicated that uptake of inhaled methyl bromide could be saturated. Any ( UC)methyl bromide equivalents absorbed, however, would be excreted by concentration-independent mechanisms. 20 references, 5 figures, 4 tables.

  6. Sodium Excretion and the Risk of Cardiovascular Disease in Patients With Chronic Kidney Disease

    PubMed Central

    Mills, Katherine T.; Chen, Jing; Yang, Wei; Appel, Lawrence J.; Kusek, John W.; Alper, Arnold; Delafontaine, Patrice; Keane, Martin G.; Mohler, Emile; Ojo, Akinlolu; Rahman, Mahboob; Ricardo, Ana C.; Soliman, Elsayed Z.; Steigerwalt, Susan; Townsend, Raymond; He, Jiang

    2016-01-01

    IMPORTANCE Patients with chronic kidney disease (CKD) are at an increased risk of cardiovascular disease (CVD) compared with the general population. Prior studies have produced contradictory results on the association of dietary sodium intake with risk of CVD, and this relationship has not been investigated in patients with CKD. OBJECTIVE To evaluate the association between urinary sodium excretion and clinical CVD events among patients with CKD. DESIGN, SETTING, AND PARTICIPANTS A prospective cohort study of patients with CKD from 7 locations in the United States enrolled in the Chronic Renal Insufficiency Cohort Study and followed up from May 2003 to March 2013. EXPOSURES The cumulative mean of urinary sodium excretion from three 24-hour urinary measurements and calibrated to sex-specific mean 24-hour urinary creatinine excretion. MAIN OUTCOMES AND MEASURES A composite of CVD events defined as congestive heart failure, stroke, ormyocardial infarction. Events were reported every 6 months and confirmed by medical record adjudication. RESULTS Among 3757 participants (mean age, 58 years; 45% women), 804 composite CVD events (575 heart failure, 305 myocardial infarction, and 148 stroke) occurred during a median 6.8 years of follow-up. From lowest (<2894 mg/24 hours) to highest (≥4548 mg/24 hours) quartile of calibrated sodium excretion, 174, 159, 198, and 273 composite CVD events occurred, and the cumulative incidence was 18.4%, 16.5%, 20.6%, and 29.8% at median follow-up. In addition, the cumulative incidence of CVD events in the highest quartile of calibrated sodium excretion compared with the lowest was 23.2% vs 13.3% for heart failure, 10.9% vs 7.8% for myocardial infarction, and 6.4% vs 2.7% for stroke at median follow-up. Hazard ratios of the highest quartile compared with the lowest quartile were 1.36 (95% CI, 1.09–1.70; P = .007) for composite CVD events, 1.34 (95% CI, 1.03–1.74; P = .03) for heart failure, and 1.81 (95% CI, 1.08–3.02; P = .02) for

  7. Increase of lipoprotein-lipase activity in skeletal muscle during heavy exercise. Relation to epinephrine excretion.

    PubMed

    Lithell, H; Cedermark, M; Fröberg, J; Tesch, P; Karlsson, J

    1981-11-01

    As part of the training programme for Swedish elite soldiers, a 10 day march is carried out with a heavy pack under active-service conditions. Six soldiers volunteered to take part in an investigation on the energy consumption with special regard to the lipid metabolism at different levels of physical effort. The degree of physical work was evaluated by continuous heart-rate recording and analysis of the excretion of epinephrine and norepinephrine in the urine. Fasting values of triglycerides and free fatty acids in blood plasma were determined and muscle biopsies (taken in the morning and in the afternoon) were analysed for lipoprotein-lipase (LPL) activity. After an overnight fast the free fatty acids were increased only in the mornings following days of heavy physical work. The plasma triglyceride concentrations were lowest in a morning proceeded by 3 days of heavy work. The muscle LPL activity in the morning was highest after a day of heavy work and lowest after days of rest. During days of heavy work this activity increased and was higher in the afternoon than in the morning. Muscle LPL activity in the afternoon was closely related to urinary excretion of epinephrine. The data indicate that LPL activity is elevated in the working skeletal muscle increasing the access of fatty acids. The degree of elevation is related to the degree of effort as described by the urinary excretion of morning. Muscle LPL activity in the afternoon was closely related to urinary excretion of epinephrine. The data indicate that LPL activity is elevated in the working skeletal muscle increasing the access of fatty acids. The degree of elevation is related to the degree of effort as described by the urinary excretion of morning. Muscle LPL activity in the afternoon was closely related to urinary excretion of epinephrine. The data indicate that LPL activity is elevated in the working skeletal muscle increasing the access of fatty acids. The degree of elevation is related to the degree

  8. [Acceleration of the excretion of monomeric 239Pu-citrate from the body as effected by pentacyne encapsulated in liposomes].

    PubMed

    Il'in, L A; Smirnov, A A; Ivannikov, A T; Parfenova, I M

    1983-01-01

    Liposomes, obtained by a modified procedure involving reverse phases, contained 2-3-times more 14C-pentacyne than the multilayer Banchem;s liposomes. Efficiency of pentacyne encapsulated in liposomes was higher, as compared with a non-encapsulated preparation in studies of urinary excretion of monomeric 239Pu-citrate in rats. Liposomal pentacyne increased most effectively the rate of the radionuclide excretion from liver tissue and skeleton as compared with the action of non-encapsulated complex-forming agent; as a result of which the radionuclide was excreted from liver tissue at a 1.6-2-times and from skeleton--with the 1.4-times higher rates. The both preparations increased the 239Pu excretion with urine and feces. The liposomal pentacyne accelerated an additional excretion of the nuclide with urine. PMID:6353751

  9. Dynamics of virus excretion via different routes in pigs experimentally infected with classical swine fever virus strains of high, moderate or low virulence.

    PubMed

    Weesendorp, Eefke; Stegeman, Arjan; Loeffen, Willie

    2009-01-01

    Classical swine fever virus (CSFV) is transmitted via secretions and excretions of infected pigs. The efficiency and speed of the transmission depends on a multitude of parameters, like quantities of virus excreted by infected pigs. This study provides quantitative data on excretion of CSFV over time from pigs infected with a highly, moderately or low virulent strain. For each strain, five individually housed pigs were infected. Virus excretion was quantified in oropharyngeal fluid, saliva, nasal fluid, lacrimal fluid, faeces, urine and skin scraping by virus titration and quantitative Real-Time Reverse Transcription Polymerase Chain Reaction (qRRT-PCR). Infectious virus was excreted in all secretions and excretions of pigs infected with the highly and moderately virulent strain, while excretion from pigs infected with the low virulent strain was mostly restricted to the oronasal route. Pigs infected with the highly virulent strain excreted significantly more virus in all their secretions and excretions over the entire infectious period than pigs infected with the moderately or low virulent strains. An exception were the pigs that developed the chronic form of infection after inoculation with the moderately virulent strain. During the entire infectious period, they excreted the largest amounts of virus via most secretions and excretions, as they excreted virus continuously and for a long duration. This study highlights the crucial role chronically infected pigs may play in the transmission of CSFV. Furthermore, it demonstrates the importance of discriminating between strains and the clinical appearance of infection when using excretion data for modelling.

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

    PubMed

    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.

  11. Characterization of Al-responsive citrate excretion and citrate-transporting MATEs in Eucalyptus camaldulensis.

    PubMed

    Sawaki, Yoshiharu; Kihara-Doi, Tomonori; Kobayashi, Yuriko; Nishikubo, Nobuyuki; Kawazu, Tetsu; Kobayashi, Yasufumi; Koyama, Hiroyuki; Sato, Shigeru

    2013-04-01

    Many plant species excrete organic acids into the rhizosphere in response to aluminum stress to protect sensitive cells from aluminum rhizotoxicity. When the roots of Eucalyptus camaldulensis, a major source of pulp production, were incubated in aluminum-toxic medium, citrate released into the solution increased as a function of time. Citrate excretion was inducible by aluminum, but not by copper or sodium chloride stresses. This indicated that citrate is the major responsive organic acid released from the roots of this plant species to protect the root tips from aluminum damage. Four genes highly homologs to known citrate-transporting multidrugs and toxic compounds exclusion proteins, named EcMATE1-4, were isolated using polymerase chain reaction-based cloning techniques. Their predicted proteins included 12 membrane spanning domains, a common structural feature of citrate-transporting MATE proteins, and consisted of 502-579 amino acids with >60 % homology to orthologous genes in other plant species. One of the homologs, designated EcMATE1, was expressed in the roots more abundantly than in the shoots and in response to both Al and low pH stresses. Ectopic expression of EcMATE1 and 3 in tobacco hairy roots enhanced Al-responsive citrate excretion. Pharmacological characterization indicated that Al-responsive citrate excretion involved a protein phosphorylation/dephosphorylation process. These results indicate that citrate excretion through citrate-transporting multidrugs and toxic compounds exclusion proteins is one of the important aluminum-tolerance mechanisms in Eucalyptus camaldulensis. PMID:23187679

  12. Metabolism and excretion of rivaroxaban, an oral, direct factor Xa inhibitor, in rats, dogs, and humans.

    PubMed

    Weinz, C; Schwarz, T; Kubitza, D; Mueck, W; Lang, D

    2009-05-01

    Rivaroxaban is a novel, oral, direct factor Xa inhibitor for the prevention and treatment of thromboembolic disorders. The objective of this study was to investigate the in vivo metabolism and excretion of rivaroxaban in rats, dogs, and humans. Single doses of [(14)C]rivaroxaban (3 and 1 mg/kg) were administered to rats (orally/intravenously) and dogs (orally), respectively. A single oral dose of [(14)C]rivaroxaban (10 mg) was administered to healthy human males (n = 4). Plasma and excreta were collected and profiled for radioactivity. Recovery of total radioactivity was high and > or = 92% in all species. Unchanged rivaroxaban was the major compound in plasma at all time points investigated, across all species. No major or pharmacologically active circulating metabolites were detected. Rivaroxaban and its metabolites were rapidly excreted; urinary excretion of radioactivity was 25 and 52%, and fecal excretion was 67 and 43% of the dose in rats and dogs, respectively. In humans, 66% of the dose was excreted renally (36% unchanged drug) and 28% in the feces. Radioactivity profiles in excreta were similar across species. Three metabolic pathways were identified: oxidative degradation of the morpholinone moiety (major pathway) and hydrolysis of the central amide bond and of the lactam amide bond in the morpholinone ring (minor pathways). M-1, the main metabolite in excreta of all species, was eliminated via both renal and fecal/biliary routes. In total, 82 to 89% of the dose administered was assigned to unchanged rivaroxaban and its metabolites in the excreta of rats, dogs, and humans. PMID:19196845

  13. Deletion of Abcg2 has differential effects on excretion and pharmacokinetics of probe substrates in rats.

    PubMed

    Huang, Liyue; Be, Xuhai; Tchaparian, Eskouhie H; Colletti, Adria E; Roberts, Jonathan; Langley, Meghan; Ling, Yun; Wong, Bradley K; Jin, Lixia

    2012-11-01

    This study was designed to characterize breast cancer resistance protein (Bcrp) knockout Abcg2(-/-) rats and assess the effect of ATP-binding cassette subfamily G member 2 (Abcg2) deletion on the excretion and pharmacokinetic properties of probe substrates. Deletion of the target gene in the Abcg2(-/-) rats was confirmed, whereas gene expression was unaffected for most of the other transporters and metabolizing enzymes. Biliary excretion of nitrofurantoin, sulfasalazine, and compound A [2-(5-methoxy-2-((2-methyl-1,3-benzothiazol-6-yl)amino)-4-pyridinyl)-1,5,6,7-tetrahydro-4H-pyrrolo[3,2-c]pyridin-4-one] accounted for 1.5, 48, and 48% of the dose in the Abcg2(+/+) rats, respectively, whereas it was decreased by 70 to 90% in the Abcg2(-/-) rats. Urinary excretion of nitrofurantoin, a significant elimination pathway, was unaffected in the Abcg2(-/-) rats, whereas renal clearance of sulfasalazine, a minor elimination pathway, was reduced by >90%. Urinary excretion of compound A was minimal. Systemic clearance in the Abcg2(-/-) rats decreased 22, 43 (p<0.05), and 57%, respectively, for nitrofurantoin, sulfasalazine, and compound A administered at 1 mg/kg and 27% for compound A administered at 5 mg/kg. Oral absorption of nitrofurantoin, a compound with high aqueous solubility and good permeability, was not limited by Bcrp. In contrast, the absence of Bcrp led to a 33- and 11-fold increase in oral exposure of sulfasalazine and compound A, respectively. These data show that Bcrp plays a crucial role in biliary excretion of these probe substrates and has differential effects on systemic clearance and oral absorption in rats depending on clearance mechanisms and compound properties. The Abcg2(-/-) rat is a useful model for understanding the role of Bcrp in elimination and oral absorption.

  14. Roles of urea production, ammonium excretion, and amino acid oxidation in acid-base balance.

    PubMed

    Mackenzie, W

    1986-02-01

    Atkinson and colleagues recently proposed several concepts that contrast with traditional views: first, that acid-base balance is regulated chiefly by the reactions leading to urea production in the liver; second, that ammonium excretion by the kidney plays no role in acid-base homeostasis; and third, that ammonium does not stimulate ureagenesis (except indirectly). To examine these concepts, plasma ions other than bicarbonate are categorized as 1) fixed cations (Na+, K+, Ca2+, and Mg2+, symbolized M+) and anions (Cl-), 2) buffer anions (A-), 3) other anions (X-), and 4) ammonium plus charged amino groups (N+). Since electroneutrality dictates that M+ + N+ = Cl- + HCO3- + A- + X-, it follows that delta HCO3- = delta(M+ - Cl-) - delta A- - delta X- + delta N+. Therefore acid-base disturbances (changes in HCO3-) can be categorized as to how they affect bodily content and hence plasma concentration of each of these four types of ions. The stoichiometry of ureagenesis, glutamine hydrolysis, ammonium and titratable acid excretion, oxidation of neutral, acidic, and basic amino acids, and oxidation of methionine, phosphoserine, and protein are examined to see how they alter these quantities. It is concluded that 1) although ureagenesis is pH dependent and also counteracts a tendency of amino acid oxidation to cause alkalosis, this tendency is inherently limited by the hyperammonemia (delta N+) that necessarily accompanies it, 2) ammonium excretion is equivalent to hydrogen excretion in its effects on acid-base balance if, and only if, it occurs in exchange for sodium or is accompanied by chloride excretion and only when the glutamate generated by glutamine hydrolysis is oxidized.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3511732

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

    NASA Astrophysics Data System (ADS)

    Aguilar, C.; Cuhel, R. L.

    2013-12-01

    Regeneration of phytoplankton growth nutrients including ammonium (NH4+) and phosphate (HPO4=) occurs in aquatic systems worldwide through biogeochemical processes of diagenesis. Organic matter falling to the bottom accumulates in sediments, and bacterial decomposition removes oxygen from the sub-surface. Anaerobic metabolism is energetically inefficient, and bacteria a few cm below the surface respire or ferment organic matter into carbon dioxide or organic acids, excreting nitrogen (NH4+) or phosphorus inorganic 'waste'. Subsurface production of bacterial metabolic products often leads to sharp gradients in porewater concentrations of NH4+ and HPO4=, which drive diffusive flux out of the sediments into overlying water. Aquatic systems with totally aerobic water overlying anoxic sediment (e.g., Lake Michigan) have muted efflux of certain inorganic nutrients arising from organic matter decomposition. For example, NH4+ is oxidized to nitrate in the upper few mm of surficial sediments by nitrifying bacteria. Strong subsurface porewater gradients, especially of redox- or geochemically-reactive compounds, often decline to low values well below the sediment-water interface, indicating transformation by sediment bacterial populations, or by purely geochemical processes such as calcium hydroxyphosphate (apatite) precipitation. For these, little flux to the water column occurs. In Lake Michigan, neither NH4+ nor HPO4= escapes substantially from the biogeochemical barriers between their diagenetic sources and overlying waters, either before or after ecosystem alteration by invasive quagga mussels (QM). Silicate and total CO2 evade unimpeded in the same cores. The organic matter deposited from the water column is also the nutrition of benthic bivalve filter feeders such as QM in Lake Michigan, or the Asian Clam in San Francisco Bay. In animal metabolism for energy production, only the carbon component is oxidized through respiration, with NH4+ (from protein) and HPO4= (from

  16. Association of Urinary Sodium Excretion With Insulin Resistance in Korean Adolescents

    PubMed Central

    Chun, Yoon Hong; Han, Kyungdo; Kim, Do Hoon; Park, Yong Gyu; Cho, Kyung Hwan; Choi, Youn Seon; Kim, Seon Mee; Kim, Yang Hyun; Nam, Ga Eun

    2016-01-01

    Abstract High sodium intake is a well-known risk factor for elevated blood pressure and is responsible for a higher incidence of cardiovascular events. Reports have suggested an association of sodium intake with insulin resistance (IR) and type 2 diabetes mellitus in adults. However, evidence on an association between sodium intake assessed on the basis of urinary sodium excretion and IR in adolescents is scarce. The present study aimed at investigating the association between urinary sodium excretion and IR among South Korean adolescents. This population-based, cross-sectional study analyzed the data obtained from the Korea National Health and Nutrition Examination Survey (KNHANES) 2009 to 2010. The data of a total of 1353 adolescents (779 boys and 574 girls) were included in the final analysis. Spot urine samples were collected, and urinary sodium excretion was estimated by using the urinary sodium concentration (U[Na+]), U[Na+] to urinary creatinine ratio (U[Na+]/Cr), and U[Na+] to specific gravity unit (SGU) ratio (U[Na+]/SGU). IR was assessed by using the homeostasis model assessment of IR (HOMA-IR). Hierarchical multivariable logistic regression analysis was performed to assess the risk for a high HOMA-IR according to urinary sodium excretion. The mean levels of U[Na+], U[Na+]/Cr, and U[Na+]/SGU were significantly higher in subjects in the highest HOMA-IR quartile (Q4) than in subjects in the lowest, second, or third quartiles (Q1–3) of HOMA-IR. The mean values of HOMA-IR and several cardiometabolic parameters tended to progressively increase with the U[Na+], U[Na+]/Cr, and U[Na+]/SGU quartiles. Q3 of U[Na+] was at a significantly higher risk than Q1 of U[Na+] of an association with Q4 of HOMA-IR, after adjustment for confounding variables. Q3 and Q4 of U[Na+]/Cr and U[Na+]/SGU, respectively, had significantly higher risks, than the respective Q1s, of an association with Q4 of HOMA-IR. The risk of an association with Q4 of HOMA-IR demonstrated significantly

  17. Tissue dosimetry, metabolism and excretion of pentavalent and trivalent monomethylated arsenic in mice after oral administration

    PubMed Central

    Hughes, Michael F.; Devesa, Vicenta; Adair, Blakely M.; Styblo, Miroslav; Kenyon, Elaina M.; Thomas, David J.

    2008-01-01

    Exposure to monomethylarsonic acid (MMA(V)) and monomethylarsonous acid (MMA(III)) can result from their formation as metabolites of inorganic arsenic and by the use of the sodium salts of MMA(V) as herbicides. This study compared the disposition of MMA(V) and MMA(III) in adult female B6C3F1 mice. Mice were gavaged po with MMA(V), either unlabeled or labeled with 14C at two dose levels (0.4 or 40 mg As/kg). Other mice were dosed po with unlabeled MMA(III) at one dose level (0.4 mg As/kg). Mice were housed in metabolism cages for collection of excreta and sacrificed serially over 24 h for collection of tissues. MMA(V)-derived radioactivity was rapidly absorbed, distributed and excreted. By 8 h post-exposure, 80% of both doses of MMA(V) were eliminated in urine and feces. Absorption of MMA(V) was dose dependent; that is, there was less than a 100-fold difference between the two dose levels in the area under the curves for the concentration-time profiles of arsenic in blood and major organs. In addition, urinary excretion of MMA(V)-derived radioactivity in the low dose group was significantly greater (P < 0.05) than in the high dose group. Conversely, fecal excretion of MMA(V)-derived radioactivity was significantly greater (P < 0.05) in the high dose group than in the low dose group. Speciation of arsenic by hydride generation-atomic absorption spectrometry in urine and tissues of mice administered MMA(V) or MMA(III) found that methylation of MMA(V) was limited while the methylation of MMA(III) was extensive. Less than 10% of the dose excreted in urine of MMA(V)-treated mice was in the form of methylated products, whereas it was greater than 90% for MMA(III)-treated mice. In MMA(V)-treated mice, 25% or less of the tissue arsenic was in the form of dimethylarsenic, whereas in MMA(III)-treated mice, 75% or more of the tissue arsenic was in the form of dimethylarsenic. Based on urinary analysis, administered dose of MMA(V) did not affect the level of its metabolites

  18. 40 CFR Table Jj-3 to Subpart Jj of... - State-Specific Volatile Solids (VS) and Nitrogen (N) Excretion Rates for Cattle

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) and Nitrogen (N) Excretion Rates for Cattle JJ Table JJ-3 to Subpart JJ of Part 98 Protection of... Volatile Solids (VS) and Nitrogen (N) Excretion Rates for Cattle State Volatile solids excretion rate (kg VS/day/1000 kg animal mass) Dairy cows Dairy heifers Feedlot steer Feedlot heifers Nitrogen...

  19. 40 CFR Table Jj-3 to Subpart Jj of... - State-Specific Volatile Solids (VS) and Nitrogen (N) Excretion Rates for Cattle

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) and Nitrogen (N) Excretion Rates for Cattle JJ Table JJ-3 to Subpart JJ of Part 98 Protection of... Volatile Solids (VS) and Nitrogen (N) Excretion Rates for Cattle State Volatile solids excretion rate (kg VS/day/1000 kg animal mass) Dairy cows Dairy heifers Feedlot steer Feedlot heifers Nitrogen...

  20. 40 CFR Table Jj-3 to Subpart Jj of... - State-Specific Volatile Solids (VS) and Nitrogen (N) Excretion Rates for Cattle

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) and Nitrogen (N) Excretion Rates for Cattle JJ Table JJ-3 to Subpart JJ of Part 98 Protection of... Volatile Solids (VS) and Nitrogen (N) Excretion Rates for Cattle State Volatile solids excretion rate (kg VS/day/1000 kg animal mass) Dairy cows Dairy heifers Feedlot steer Feedlot heifers Nitrogen...

  1. 40 CFR Table Jj-3 to Subpart Jj of... - State-Specific Volatile Solids (VS) and Nitrogen (N) Excretion Rates for Cattle

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) and Nitrogen (N) Excretion Rates for Cattle JJ Table JJ-3 to Subpart JJ of Part 98 Protection of... Volatile Solids (VS) and Nitrogen (N) Excretion Rates for Cattle State Volatile solids excretion rate (kg VS/day/1000 kg animal mass) Dairy cows Dairy heifers Feedlot steer Feedlot heifers Nitrogen...

  2. Fecapentaene excretion and fecal mutagenicity in relation to nutrient intake and fecal parameters in humans on omnivorous and vegetarian diets.

    PubMed

    de Kok, T M; van Faassen, A; Bausch-Goldbohm, R A; ten Hoor, F; Kleinjans, J C

    1992-02-14

    Fecapentaenes are strong fecal mutagenic compounds presumably occurring in the majority of Western human individuals, and are possibly essential initiators of colon carcinogenesis. Dietary factors have been shown to influence colorectal cancer risk and to modulate both fecal mutagenicity and fecapentaene concentrations. Therefore, in this study, excretion of fecapentaenes is determined in humans consuming either vegetarian or omnivorous diets. The results show that the most predominant fecapentaene forms are excreted in higher concentrations by vegetarians. Consumption of cereal fiber, calcium and carotene as well as fecal concentrations of iso-lithocholic acid were found to correlate positively with excreted concentrations of one or more fecapentaene analogues. On average, 22% of excreted fecapentaene concentrations was found to be related to nutrient intake in stepwise regression models. Dietary calcium intake was found to be the most significant factor positively correlating with excreted fecapentaene concentrations. Intake of mono-unsaturated fatty acids or fiber from vegetables and fruit could be shown to correlate with fecapentaene excretion to a lesser degree. Despite high fecapentaene concentrations in fecal dichloromethane extracts, only 1 out of 20 samples revealed significant mutagenic activity in Salmonella typhimurium TA 100. Further, aqueous extracts of feces from omnivores appeared to be equally mutagenic as feces from vegetarians and contained non-detectable concentrations of fecapentaenes. It is concluded that dietary factors do affect excreted fecapentaene levels, but only to a relatively minor extent. Since vegetarians at low risk for colorectal cancer excrete higher concentrations of fecapentaenes, it could be hypothesized that relatively increased fecapentaene excretion in combination with antimutagenic compounds in feces represents colon cancer prevention.

  3. The effects of repeated parenteral administration of chelating agents on the distribution and excretion of uranium

    SciTech Connect

    Domingo, J.L.; Ortega, A.; Llobet, J.M.; Paternain, J.L.; Corbella, J.

    1989-04-01

    The effects of repeated ip administration of gallic acid, 4,5-dihydroxy-1,3-benzenedisulfonic acid (Tiron), diethylenetriaminepentaacetic acid (DTPA), and 5-aminosalicylic acid (5-AS) on the distribution and excretion of uranium were assessed in male Swiss mice. Only Tiron significantly increased the amount of uranium excreted into urine and feces. A significant decrease in the concentration of uranium in liver, spleen and bone was observed after administration of Tiron, whereas injection of gallic acid or DTPA resulted in a significant decrease in the concentration of the metal in the liver. The results show that Tiron was consistently the most effective chelator of those tested in the treatment of uranium poisoning after repeated daily administration of the metal.

  4. Effects of hydroalcoholic extracts of Portulaca pilosa and Achyrocline satureioides on urinary sodium and potassium excretion.

    PubMed

    Rocha, M J; Fulgencio, S F; Rabetti, A C; Nicolau, M; Poli, A; Simões, C M; Ribeiro-do-Valle, R M

    1994-07-22

    Porulaca pilosa has been used in Brazil as a traditional remedy to cause diuresis, antipyresis and analgesia. Achyrocline satureioides has been used in folk medicine as antiinflammatory, hypoglycemic, sedative and to treat gastrointestinal disorders such as diarrhea and dysentery suggesting that it may affect salt and water reabsorption by the gastrointestinal tract. In the current study, hydroalcoholic extracts of both plants were investigated in order to examine their renal effects. The results support the claim that extracts of P. pilosa present renal effects but not the popular belief that it affects diuresis. It has also been provided that, in rats, it causes an increase in K excretion without a concomitant change in water diuresis or Na excretion. Our findings also support the popular belief that A. satureioides does not apparently have renal effects and it might change renal ion transport based on observations that it affects gastrointestinal reabsorption.

  5. High-throughput approaches for evaluating absorption, distribution, metabolism and excretion properties of lead compounds.

    PubMed

    Tarbit, M H; Berman, J

    1998-06-01

    Combinatorial chemistry methods and high-throughput screening for leads in industrial drug discovery have generated a potential bottleneck in the optimisation processes that seek to align potency with good pharmacokinetics in order to produce good medicines. This has resulted in the need for higher throughput methods of screening for absorption, distribution, metabolism and excretion properties. Significant progress has been made in throughput of in vivo pharmacokinetic studies, with the introduction of cassette, or multiple-in-one, protocols. In this technique, typically up to ten compounds are administered in one dose and analysed concomitantly on the mass spectrometer. High-throughput methods in in vitro absorption, distribution, metabolism and excretion are less well-developed as yet, and current approaches comprise automation of well-established methods for absorption using cell lines and metabolism using liver microsomes.

  6. A New Model of Reverse Cholesterol Transport: EnTICEing Strategies to Stimulate Intestinal Cholesterol Excretion

    PubMed Central

    Temel, Ryan E.; Brown, J. Mark

    2015-01-01

    Cardiovascular disease (CVD) remains the largest cause of mortality in most developed countries. Although recent failed clinical trials and Mendelian randomization studies have called into question the high density lipoprotein (HDL) hypothesis, it remains well accepted that stimulating the process of reverse cholesterol transport (RCT) can prevent or even regress atherosclerosis. The prevailing model for RCT is that cholesterol from the artery wall must be delivered to the liver where it is secreted into bile before leaving the body through fecal excretion. However, many studies have demonstrated that RCT can proceed through a non-biliary pathway known as transintestinal cholesterol excretion (TICE). The goal of this review is to discuss the current state of knowledge of the TICE pathway, with emphasis on points of therapeutic intervention. PMID:25930707

  7. Genetic manipulation of a metabolic enzyme and a transcriptional regulator increasing succinate excretion from unicellular cyanobacterium

    PubMed Central

    Osanai, Takashi; Shirai, Tomokazu; Iijima, Hiroko; Nakaya, Yuka; Okamoto, Mami; Kondo, Akihiko; Hirai, Masami Y.

    2015-01-01

    Succinate is a building block compound that the U.S. Department of Energy (DOE) has declared as important in biorefineries, and it is widely used as a commodity chemical. Here, we identified the two genes increasing succinate production of the unicellular cyanobacterium Synechocystis sp. PCC 6803. Succinate was excreted under dark, anaerobic conditions, and its production level increased by knocking out ackA, which encodes an acetate kinase, and by overexpressing sigE, which encodes an RNA polymerase sigma factor. Glycogen catabolism and organic acid biosynthesis were enhanced in the mutant lacking ackA and overexpressing sigE, leading to an increase in succinate production reaching five times of the wild-type levels. Our genetic and metabolomic analyses thus demonstrated the effect of genetic manipulation of a metabolic enzyme and a transcriptional regulator on succinate excretion from this cyanobacterium with the data based on metabolomic technique. PMID:26500619

  8. Tissue dosimetry, metabolism and excretion of pentavalent and trivalent dimethylated arsenic in mice after oral administration

    SciTech Connect

    Hughes, Michael F. Devesa, Vicenta; Adair, Blakely M.; Conklin, Sean D.; Creed, John T.; Styblo, Miroslav; Kenyon, Elaina M.; Thomas, David J.

    2008-02-15

    Dimethylarsinic acid (DMA(V)) is a rat bladder carcinogen and the major urinary metabolite of administered inorganic arsenic in most mammals. This study examined the disposition of pentavalent and trivalent dimethylated arsenic in mice after acute oral administration. Adult female mice were administered [{sup 14}C]-DMA(V) (0.6 or 60 mg As/kg) and sacrificed serially over 24 h. Tissues and excreta were collected for analysis of radioactivity. Other mice were administered unlabeled DMA(V) (0.6 or 60 mg As/kg) or dimethylarsinous acid (DMA(III)) (0.6 mg As/kg) and sacrificed at 2 or 24 h. Tissues (2 h) and urine (24 h) were collected and analyzed for arsenicals. Absorption, distribution and excretion of [{sup 14}C]-DMA(V) were rapid, as radioactivity was detected in tissues and urine at 0.25 h. For low dose DMA(V) mice, there was a greater fractional absorption of DMA(V) and significantly greater tissue concentrations of radioactivity at several time points. Radioactivity distributed greatest to the liver (1-2% of dose) and declined to less than 0.05% in all tissues examined at 24 h. Urinary excretion of radioactivity was significantly greater in the 0.6 mg As/kg DMA(V) group. Conversely, fecal excretion of radioactivity was significantly greater in the high dose group. Urinary metabolites of DMA(V) included DMA(III), trimethylarsine oxide (TMAO), dimethylthioarsinic acid and trimethylarsine sulfide. Urinary metabolites of DMA(III) included TMAO, dimethylthioarsinic acid and trimethylarsine sulfide. DMA(V) was also excreted by DMA(III)-treated mice, showing its sensitivity to oxidation. TMAO was detected in tissues of the high dose DMA(V) group. The low acute toxicity of DMA(V) in the mouse appears to be due in part to its minimal retention and rapid elimination.

  9. Biliary albumin excretion induced by bile salts in rats is a pathological phenomenon

    SciTech Connect

    Ohta, M.; Kitani, K.; Kanai, S. )

    1989-09-01

    The bile to plasma 125I-albumin concentration ratio (B/P ratio) was examined before and during various bile salt infusions in male Wistar rats that had previously received iv injection of 125I-albumin. Endogenous rat albumin and IgG concentrations in the bile were also determined by a single radial immunodiffusion method. Taurocholate (TC) infusion (1.0 mumol/min/100 g body wt) significantly increased the bile flow rate in the first hr but the flow began to decline in the second hr. The B/P ratio as well as rat albumin (and IgG) excretion into the bile significantly increased as early as 15 min after the start of TC infusion, and the increase became more pronounced in the second hr, when the bile flow began to decrease. Infusion of taurochenodeoxycholate (TCDC, 0.4 mumol/min/100 g) caused a reduction in bile flow 15 min after the start of infusion but the B/P ratio increased 40 times at its peak compared with the basal value before the bile salt infusion. Simultaneous infusion of tauroursodeoxycholate (TUDC, 0.6 mumol/min/100 g) and TCDC not only abolished the cholestasis induced by TCDC but maintained stable choleresis as long as for 2 hr. During this choleretic period, the B/P ration never exceeded the basal value. The choleresis induced by either taurodehydrocholate (TDHC) or bucolome was not accompanied by enhanced albumin excretion. In rats given TDHC infusion, albumin excretion started to increase only after the bile flow began to decline following the initial choleretic period. The enhanced excretion of albumin induced by TC and TCDC is therefore suggested to be caused not by the choleresis per se but by a possible concomitant increase in the communication between sinusoids and bile canaliculi, which eventually leads to cholestasis.

  10. The influence of neuropeptides on Malpighian tubule writhing and its significance for excretion.

    PubMed

    Coast, G M

    1998-01-01

    Diuretic peptides (locustakinin and Locusta-DH) increase the spontaneous contractile activity of visceral muscle fibers associated with Malpighian tubules from the migratory locust (Locusta migratoria) at concentrations that increase urine production. Muscle activity is shown to assist the flow of material in the tubule lumen, but is not essential for diuresis. Tubule writhing also serves to reduce unstirred layers (USLs) at the basolateral surface of the epithelium and thereby facilitates the excretion of solutes entering the lumen by passive diffusion. PMID:9533634

  11. Effects of kefir on coccidial oocysts excretion and performance of dairy goat kids following weaning.

    PubMed

    Daş, Gürbüz; Ataşoğlu, Cengiz; Akbağ, Hande Işıl; Tölü, Cemil; Yurtman, Ismail Yaman; Savaş, Türker

    2012-06-01

    The aim of this study was to investigate effects of kefir, a traditional source of probiotic, on coccidial oocysts excretion and on the performance of dairy goat kids following weaning. Twin kids were randomly allocated to one of two groups at weaning. Kids of the first group received 20 ml of kefir daily for 6 weeks (KEF), while kids in the control group were given a placebo (CON). Individual faecal samples were regularly (n = 18 per kid) taken to quantify the number of coccidial oocysts per gram of faeces (OpG). There were no differences between the groups in terms of body weight development (P > 0.05) and feed consumption. Kids of both groups were not able to consume enough feed to meet their nutrient requirements during the first 3 weeks following weaning. KEF had a lower frequency of OpG positive samples than CON (P = 0.043). Kefir did not affect the maximum oocyst excretion and age of the kids at the highest oocyst excretion (P > 0.05). KEF shed numerically 35% lower coccidial oocysts than the controls, which corresponded to a statistical tendency (P = 0.074) in lowering Log-OpG in comparison to CON. While KEF had a lower frequency of OpG positive samples and tended to shed lower OPG by around one-third, the frequency of diarrhea, level of highest oocyst excretion, and performance of the kids remained unaffected. Therefore, it is concluded that overall effects of kefir do not have a significant impact on sub-clinical infection and performance in weaned kids under relatively high-hygienic farming conditions.

  12. Fluoride excretion of adults living in border regions with either water or salt fluoridation.

    PubMed

    Guindy, Joseph S; Gysin, Ralph; Kränzlin, Marius; Gasser, Thomas C; Hauck, Kirsten; Meyer, Jürg

    2006-01-01

    The canton of Basel-Stadt was the only canton in Switzerland which introduced drinking water fluoridation (DWF) at 1 ppm (mg/l). All other cantons have relied on fluoridated domestic salt at 250 ppm F as the main vehicle for basic fluoride exposure. It has been suggested that persons living and working in the DWF areas or persons commuting to the DWF areas may be exposed to higher than optimal doses of fluoride. The objective of this present study was to determine the urinary fluoride excretion of adults living and or working in neighboring areas of either salt or water fluoridation. In this study, 24-hour urine was collected from 69 healthy subjects and tested for fluoride concentration. The mean fluoride concentration for all participants was 0.55 +/- 0.25 ppm (mg/l) ranging from 1.14 to 0.09 ppm. The mean fluoride excretion was 0.95 +/- 0.47 mg F/d ranging from 0.18 to 2.12 mg F/d. The 33 subjects living in a DWF region showed a mean urine fluoride concentration of 0.64 +/- 0.24 ppm (mg/l) and a mean fluoride excretion of 1.14 +/- 0.48 mg F/d. Those 36 subjects living in a region without DWF showed a mean urine fluoride concentration of 0.47 +/- 0.24 ppm (mg/l) and a mean fluoride excretion of 0.78 +/- 0.40 mg F/d. A significant difference between the two means of the groups living in regions with or without DWF was detected when the Mann-Whitney statistical test was applied (p < 0.005). The combined intake of fluoridated drinking water and fluoridated table salt in the sub-group of 11 subjects who commuted showed an overall increase in fluoride urine concentration. The measured values, however, were not significantly different from the other sub-groups.

  13. [Intestinal absorption and urinary excretion of triethylenetetramine for Wilson's disease in rat].

    PubMed

    Kobayashi, M; Sugawara, M; Saitoh, H; Iseki, K; Miyazaki, K

    1990-10-01

    Triethylenetetramine.2.HCl (trientine, TE) is an orphan drug for the treatment of Wilson's disease. There has been no reports regarding the absorption, distribution, metabolism, and excretion in the body. In the current study, the absorption and excretion of TE in rats were examined. The observed mean percentage amount of TE absorbed at the jejunum and ileum with the loop method for 1 h was 42.0% and 22.5%, respectively. Tight junction blocking agent inhibited the absorption of TE from the jejunum loop with 27%, but the absorption of TE from the ileum loop was not affected by this blocking agent. Therefore, the main absorption route for TE might be permeation across the plasma membrane of intestinal epithelial cells. TE and amikacin, a polycationic compound like TE, bound to the brush border membrane (BBM) of rat small intestine in the absence of inorganic ions such as Na+, K+, Ca2+, Mg2+ and Cu2+. But the binding of TE to BBM was inhibited markedly under the physiological concentration of these ions. The bioavailability of TE was below 10% and the plasma levels of TE in non-fasted rats were significantly lower than that observed in fasted rats. The urinary excretion of unchanged TE during 24 h was only 3.5% of the orally administered dose. However, the urinary excretion of total TE including metabolites, though they have not been identified, was 35.7%. These results suggest that low bioavailability of TE might be due to the rapid metabolism in the body after absorption from the gastrointestinal tract.

  14. Sodium and potassium urinary excretion and dietary intake: a cross-sectional analysis in adolescents

    PubMed Central

    Gonçalves, Carla; Abreu, Sandra; Padrão, Patrícia; Pinho, Olívia; Graça, Pedro; Breda, João; Santos, Rute; Moreira, Pedro

    2016-01-01

    Background Hypertension is the leading cause for heart disease and stroke, for mortality and morbidity worldwide, and a high sodium-to-potassium intake ratio is considered a stronger risk factor for hypertension than sodium alone. Objective This study aims to evaluate sodium and potassium urinary excretion, and assess the food sources of these nutrients in a sample of Portuguese adolescents. Design A cross-sectional study with a sample of 250 Portuguese adolescents. Sodium and potassium excretion were measured by one 24-h urinary collection, and the coefficient of creatinine was used to validate completeness of urine collections. Dietary sources of sodium and potassium were assessed using a 24-h dietary recall. Results Valid urine collections were provided by 200 adolescents (118 girls) with a median age of 14.0 in both sexes (p=0.295). Regarding sodium, the mean urinary excretion was 3,725 mg/day in boys and 3,062 mg/day in girls (p<0.01), and 9.8% of boys and 22% of girls met the World Health Organization (WHO) recommendations for sodium intake. Concerning potassium, the mean urinary excretion was 2,237 mg/day in boys and 1,904 mg/day in girls (p<0.01), and 6.1% of boys and 1.7% of girls met the WHO recommendations for potassium intake. Major dietary sources for sodium intake were cereal and cereal products (41%), meat products (16%), and milk and milk products (11%); and for potassium intake, main sources were milk and milk products (21%), meat products (17%), and vegetables (15%). Conclusions Adolescents had a high-sodium and low-potassium diet, well above the WHO recommendations. Health promotion interventions are needed in order to decrease sodium and increase potassium intake. PMID:27072344

  15. Urinary excretion of uranium in adult inhabitants of the Czech Republic.

    PubMed

    Malátová, Irena; Bečková, Věra; Kotík, Lukáš

    2016-02-01

    The main aim of this study was to determine and evaluate urinary excretion of uranium in the general public of the Czech Republic. This value should serve as a baseline for distinguishing possible increase in uranium content in population living near legacy sites of mining and processing uranium ores and also to help to distinguish the proportion of the uranium content in urine among uranium miners resulting from inhaled dust. The geometric mean of the uranium concentration in urine of 74 inhabitants of the Czech Republic was 0.091 mBq/L (7.4 ng/L) with the 95% confidence interval 0.071-0.12 mBq/L (5.7-9.6 ng/L) respectively. The geometric mean of the daily excretion was 0.15 mBq/d (12.4 ng/d) with the 95% confidence interval 0.12-0.20 mBq/d (9.5-16.1 ng/d) respectively. Despite the legacy of uranium mines and plants processing uranium ore in the Czech Republic, the levels of uranium in urine and therefore, also human body content of uranium, is similar to other countries, esp. Germany, Slovenia and USA. Significant difference in the daily urinary excretion of uranium was found between individuals using public supply and private water wells as a source of drinking water. Age dependence of daily urinary excretion of uranium was not found. Mean values and their range are comparable to other countries, esp. Germany, Slovenia and USA.

  16. Discontinuous ammonia excretion and glutamine storage in littoral Oniscidea (Crustacea: Isopoda): testing tidal and circadian models.

    PubMed

    Nakamura, Maya; Wright, Jonathan C

    2013-01-01

    A key evolutionary development facilitating land colonization in terrestrial isopods (Isopoda: Oniscidea) is the intermittent liberation of waste nitrogen as volatile ammonia. Intermittent ammonia release exploits glutamine (Gln) as an intermediary nitrogen store. Here, we explore the relationship between temporal patterns of ammonia release and Gln accumulation in three littoral oniscideans from Southern California. Results are interpreted in terms of water availability, habitat, activity patterns, and ancestry. A two-way experimental design was used to test whether ammonia excretion and Gln accumulation follow a tidal or diel periodicity. Ammonia excretion was studied in the laboratory using chambers with or without available seawater and using an acid trap to collect volatile ammonia. Ligia occidentalis releases ammonia directly into seawater and accumulates Gln during low tide (48.9 ± 6.5 μmol g⁻¹ at low tide, 24.1 ± 3.0 μmol g⁻¹ at high tide), indicating that excretion is tidally constrained. Alloniscus perconvexus and Tylos punctatus can excrete ammonia directly into seawater or utilize volatilization. Both species burrow in sand by day and show a diel excretory pattern, accumulating Gln nocturnally (31.8 ± 2.7 μmol g⁻¹ at dawn and 21.8 ± 2.3 μmol g⁻¹ at dusk for A. perconvexus; 85.7 ± 15.1 μmol g⁻¹ at dawn and 25.4 ± 2.9 μmol g⁻¹ at dusk for T. punctatus) and liberating ammonia diurnally. Glutaminase shows higher activity in terrestrial (0.54-0.86 U g⁻¹) compared to intertidal (0.25-0.31 U g⁻¹) species, consistent with the need to generate high PNH₃ for volatilization. The predominant isoform in Armadillidium vulgare is phosphate dependent and maleate independent; phosphate is a plausible regulator in vivo. PMID:22836297

  17. Correlation between sodium and potassium excretion in 24- and 12-h urine samples.

    PubMed

    Mill, J G; Silva, A B T da; Baldo, M P; Molina, M C B; Rodrigues, S L

    2012-09-01

    Low-sodium and high-potassium diets have been recommended as an adjunct to prevention and treatment of hypertension. Analysis of these nutrients in 24-h urine has been considered the reference method to estimate daily intake of these minerals. However, 24-h urine collection is difficult in epidemiological studies, since urine must be collected and stored in job environments. Therefore, strategies for shorter durations of urine collection at home have been proposed. We have previously reported that collecting urine during a 12-h period (overnight) is more feasible and that creatinine clearance correlated strongly with that detected in 24-h samples. In the present study, we collected urine for 24 h divided into two 12-h periods (from 7:00 am to 7:00 pm and from 7:00 pm to 7:00 am next day). A sample of 109 apparently healthy volunteers aged 30 to 74 years of both genders working in a University institution was investigated. Subjects with previous myocardial infarction, stroke, renal insufficiency, and pregnant women were not included. Significant (P < 0.001) Spearman correlation coefficients (r s) were found between the total amount of sodium and potassium excreted in the urine collected at night and in the 24-h period (r s = 0.76 and 0.74, respectively). Additionally, the 12-h sodium and potassium excretions (means ± SD, 95% confidence interval) corresponded to 47.3 ± 11.2%, 95%CI = 45.3-49.3, and 39.3 ± 4.6%, 95%CI = 37.3-41.3, respectively, of the 24-h excretion of these ions. Therefore, these findings support the assumption that 12-h urine collected at night can be used as a reliable tool to estimate 24-h intake/excretion of sodium and potassium.

  18. Increased Klk9 Urinary Excretion Is Associated to Hypertension-Induced Cardiovascular Damage and Renal Alterations

    PubMed Central

    Blázquez-Medela, Ana M.; García-Sánchez, Omar; Quirós, Yaremi; Blanco-Gozalo, Victor; Prieto-García, Laura; Sancho-Martínez, Sandra M.; Romero, Miguel; Duarte, Juan M.; López-Hernández, Francisco J.; López-Novoa, José M.; Martínez-Salgado, Carlos

    2015-01-01

    Abstract Early detection of hypertensive end-organ damage and secondary diseases are key determinants of cardiovascular prognosis in patients suffering from arterial hypertension. Presently, there are no biomarkers for the detection of hypertensive target organ damage, most outstandingly including blood vessels, the heart, and the kidneys. We aimed to validate the usefulness of the urinary excretion of the serine protease kallikrein-related peptidase 9 (KLK9) as a biomarker of hypertension-induced target organ damage. Urinary, plasma, and renal tissue levels of KLK9 were measured by the Western blot in different rat models of hypertension, including angiotensin-II infusion, DOCA-salt, L-NAME administration, and spontaneous hypertension. Urinary levels were associated to cardiovascular and renal injury, assessed by histopathology. The origin of urinary KLK9 was investigated through in situ renal perfusion experiments. The urinary excretion of KLK9 is increased in different experimental models of hypertension in rats. The ACE inhibitor trandolapril significantly reduced arterial pressure and the urinary level of KLK9. Hypertension did not increase kidney, heart, liver, lung, or plasma KLK9 levels. Hypertension-induced increased urinary excretion of KLK9 results from specific alterations in its tubular reabsorption, even in the absence of overt nephropathy. KLK9 urinary excretion strongly correlates with cardiac hypertrophy and aortic wall thickening. KLK9 appears in the urine in the presence of hypertension as a result of subtle renal handling alterations. Urinary KLK9 might be potentially used as an indicator of hypertensive cardiac and vascular damage. PMID:26469898

  19. Urinary excretion of cortisol from rhesus monkeys (Macaca mulatta) habituated to restraint

    NASA Technical Reports Server (NTRS)

    Wade, C. E.; Ortiz, R. M.

    1997-01-01

    Use of monkeys in research has often required that they be restrained in a chair. However, chair restraint can elicit an initial neuroendocrine stress response. Also, inactivity associated with restraint can induce muscular atrophy. We proposed that prior habituation of monkeys to chair restraint would attenuate these neuroendocrine responses without causing substantial muscle wasting. Four rhesus monkeys (Macaca mulatta) were trained and habituated to a restraint chair specifically designed for spaceflight. During the study, monkeys were placed in metabolic cages for 7 days (prerestraint, Phase I), placed in a chair restraint for 18 days (Phase II), and then returned to their metabolic cages for 5 days (postrestraint, Phase III). Urine was collected between 0700-1100 daily, and measurements of cortisol, creatinine, and electrolyte concentrations were adjusted for hourly excretion rates. Body weights of the monkeys did not change between start of the prerestraint and postrestraint phases (10.3 +/- 0.8 vs. 10.3 +/- 0.9 kg, respectively). During the 3 phases, mean excretion rate of cortisol did not change (24.1 +/- 10.3, 26.7 +/- 7.7, and 19.3 +/- 5.8 microg/h, respectively). Mean excretion rate of creatinine (37.3 +/- 7.5, 37.5 +/- 12.2, and 36.9 +/- 17.1 mg/h, respectively), Na+ (3.3 +/- 1.2, 3.2 +/- 1.2, 2.2 +/- 1.8 mmol/h, respectively), and K+ (5.3 +/- 1.8, 5.4 +/- 1.6, and 4.3 +/- 2.8 mmol/h, respectively) were also not altered. Lack of an increase in excreted urinary cortisol suggested that prior habituation to chair restraint attenuated neuroendocrine responses reported previously. Also, the chair restraint method used appeared to allow adequate activity, because the monkeys did not have indices of muscle wasting.

  20. Urinary sodium excretion and kidney failure in nondiabetic chronic kidney disease.

    PubMed

    Fan, Li; Tighiouart, Hocine; Levey, Andrew S; Beck, Gerald J; Sarnak, Mark J

    2014-09-01

    Current guidelines recommend under 2 g/day sodium intake in chronic kidney disease, but there are a few studies relating sodium intake to long-term outcomes. Here we evaluated the association of mean baseline 24-h urinary sodium excretion with kidney failure and a composite outcome of kidney failure or all-cause mortality using Cox regression in 840 participants enrolled in the Modification of Diet in Renal Disease Study. Mean 24-h urinary sodium excretion was 3.46 g/day. Kidney failure developed in 617 participants, and the composite outcome was reached in 723. In the primary analyses, there was no association between 24-h urine sodium and kidney failure (HR 0.99 (95% CI 0.91-1.08)) nor on the composite outcome (HR 1.01 (95% CI 0.93-1.09)), each per 1 g/day higher urine sodium. In exploratory analyses, there was a significant interaction of baseline proteinuria and sodium excretion with kidney failure. Using a two-slope model, when urine sodium was under 3 g/day, higher urine sodium was associated with increased risk of kidney failure in those with baseline proteinuria under 1 g/day and with lower risk of kidney failure in those with baseline proteinuria of ⩾ 1 g/day. There was no association between urine sodium and kidney failure when urine sodium was ⩾ 3 g/day. Results were consistent using first baseline and time-dependent urinary sodium excretion. Thus, we noted no association of urine sodium with kidney failure. Results of the exploratory analyses need to be verified in additional studies and the mechanism explored.

  1. Urinary excretion of uranium in adult inhabitants of the Czech Republic.

    PubMed

    Malátová, Irena; Bečková, Věra; Kotík, Lukáš

    2016-02-01

    The main aim of this study was to determine and evaluate urinary excretion of uranium in the general public of the Czech Republic. This value should serve as a baseline for distinguishing possible increase in uranium content in population living near legacy sites of mining and processing uranium ores and also to help to distinguish the proportion of the uranium content in urine among uranium miners resulting from inhaled dust. The geometric mean of the uranium concentration in urine of 74 inhabitants of the Czech Republic was 0.091 mBq/L (7.4 ng/L) with the 95% confidence interval 0.071-0.12 mBq/L (5.7-9.6 ng/L) respectively. The geometric mean of the daily excretion was 0.15 mBq/d (12.4 ng/d) with the 95% confidence interval 0.12-0.20 mBq/d (9.5-16.1 ng/d) respectively. Despite the legacy of uranium mines and plants processing uranium ore in the Czech Republic, the levels of uranium in urine and therefore, also human body content of uranium, is similar to other countries, esp. Germany, Slovenia and USA. Significant difference in the daily urinary excretion of uranium was found between individuals using public supply and private water wells as a source of drinking water. Age dependence of daily urinary excretion of uranium was not found. Mean values and their range are comparable to other countries, esp. Germany, Slovenia and USA. PMID:26650830

  2. Discontinuous ammonia excretion and glutamine storage in littoral Oniscidea (Crustacea: Isopoda): testing tidal and circadian models.

    PubMed

    Nakamura, Maya; Wright, Jonathan C

    2013-01-01

    A key evolutionary development facilitating land colonization in terrestrial isopods (Isopoda: Oniscidea) is the intermittent liberation of waste nitrogen as volatile ammonia. Intermittent ammonia release exploits glutamine (Gln) as an intermediary nitrogen store. Here, we explore the relationship between temporal patterns of ammonia release and Gln accumulation in three littoral oniscideans from Southern California. Results are interpreted in terms of water availability, habitat, activity patterns, and ancestry. A two-way experimental design was used to test whether ammonia excretion and Gln accumulation follow a tidal or diel periodicity. Ammonia excretion was studied in the laboratory using chambers with or without available seawater and using an acid trap to collect volatile ammonia. Ligia occidentalis releases ammonia directly into seawater and accumulates Gln during low tide (48.9 ± 6.5 μmol g⁻¹ at low tide, 24.1 ± 3.0 μmol g⁻¹ at high tide), indicating that excretion is tidally constrained. Alloniscus perconvexus and Tylos punctatus can excrete ammonia directly into seawater or utilize volatilization. Both species burrow in sand by day and show a diel excretory pattern, accumulating Gln nocturnally (31.8 ± 2.7 μmol g⁻¹ at dawn and 21.8 ± 2.3 μmol g⁻¹ at dusk for A. perconvexus; 85.7 ± 15.1 μmol g⁻¹ at dawn and 25.4 ± 2.9 μmol g⁻¹ at dusk for T. punctatus) and liberating ammonia diurnally. Glutaminase shows higher activity in terrestrial (0.54-0.86 U g⁻¹) compared to intertidal (0.25-0.31 U g⁻¹) species, consistent with the need to generate high PNH₃ for volatilization. The predominant isoform in Armadillidium vulgare is phosphate dependent and maleate independent; phosphate is a plausible regulator in vivo.

  3. DBcAMP stimulates vesicle transport and HRP excretion in isolated perfused rat liver.

    PubMed

    Hayakawa, T; Bruck, R; Ng, O C; Boyer, J L

    1990-11-01

    To clarify the effect of adenosine 3',5'-cyclic monophosphate (cAMP) on the transcytotic vesicle pathway, we measured the biliary excretion of bile acid, phospholipid, and horseradish peroxidase (HRP) in the isolated perfused rat liver (IPRL) with or without infusion of N6,2'-O-dibutyryl-cAMP (DBcAMP). A linear relationship between bile flow and bile acid excretion was observed in both control and DBcAMP-infused livers. DBcAMP increased the y-axis intercept from 1.10 +/- 0.16 to 1.48 +/- 0.19 microliters.min-1.g liver-1 (P less than 0.01) and the slope from 6.5 +/- 1.99 to 10.77 +/- 1.71 microliters/mumol bile acid (P less than 0.01). DBcAMP also increased the biliary excretion of bile acid and phospholipid during a 1.0 mumol/min infusion of taurocholate. When HRP was pulse loaded for 1 min, HRP appeared in bile in early (4-6 min) and late (20-25 min) peaks. DBcAMP markedly increased the late peak of HRP from 0.33 +/- 0.08 to 1.15 +/- 0.32 ng.min-1.g liver-1 (P less than 0.01), a phenomenon blocked by colchicine. An electron-microscopic morphometric analysis indicated that DBcAMP increased both the density and %area of HRP-containing vesicles in the pericanalicular area, compared with controls, 18 min after a 1-min pulse of HRP. DBcAMP had no effect on the uptake rate of HRP in 4-h primary hepatocyte cultures but stimulated biliary excretion of HRP when preloaded in the IPRL. These findings indicate that cAMP regulates excretory function in part by stimulating the microtubule-dependent transcytotic vesicle transport system.

  4. Energy and nutrient deposition and excretion in the reproducing sow: model development and evaluation.

    PubMed

    Hansen, A V; Strathe, A B; Theil, P K; Kebreab, E

    2014-06-01

    Air and nutrient emissions from swine operations raise environmental concerns. During the reproduction phase, sows consume and excrete large quantities of nutrients. The objective of this study was to develop a mathematical model to describe energy and nutrient partitioning and predict manure excretion and composition and methane emissions on a daily basis. The model was structured to contain gestation and lactation modules, which can be run separately or sequentially, with outputs from the gestation module used as inputs to the lactation module. In the gestating module, energy and protein requirements for maintenance, and fetal and maternal growth were described. In the lactating module, a factorial approach was used to estimate requirements for maintenance, milk production, and maternal growth. The priority for nutrient partitioning was assumed to be in the order of maintenance, milk production, and maternal growth with body tissue losses constrained within biological limits. Global sensitivity analysis showed that nonlinearity in the parameters was small. The model outputs considered were the total protein and fat deposition, average urinary and fecal N excretion, average methane emission, manure carbon excretion, and manure production. The model was evaluated using independent data sets from the literature using root mean square prediction error (RMSPE) and concordance correlation coefficients. The gestation module predicted body fat gain better than body protein gain, which was related to predictions of body fat and protein loss from the lactation model. Nitrogen intake, urine N, fecal N, and milk N were predicted with RMSPE as percentage of observed mean of 9.7, 17.9, 10.0, and 7.7%, respectively. The model provided a framework, but more refinements and improvements in accuracy of prediction (particularly urine N) are required before the model can be used to assess environmental mitigation options from sow operations.

  5. Urinary trimethylselenonium excretion by the rat: effect of level and source of /sup 75/Se

    SciTech Connect

    Nahapetian, A.T.; Janghorbani, M.; Young, V.R.

    1983-02-01

    The purpose of this study was to explore in rats the urinary metabolites of selenium (Se), by using (/sup 75/Se)selenomethionine, (/sup 75/Se)selenocystine, and (/sup 75/Se)selenite, and to assess the effects of low and high levels of Se intake on trimethylselenonium ion (TMSe) excretion in urine. Male adult rats were adapted for 6 weeks to a commercial rat laboratory stock diet (0.25 ppm Se). They were then starved for 24 hours and given an oral dose of either low (16 micrograms Se/kg body weight) or high (1500 micrograms Se/kg body weight) Se as the test Se compounds. Appearance of radioactivity in TMSe and non-TMSe Se metabolites in urine was monitored for 48 hours. About 40% of the /sup 75/Se dose was excreted in urine. TMSe was the major urinary Se metabolite (57-69% of urinary /sup 75/Se and 16-25% of oral /sup 75/Se dose) at high, and a minor urinary Se metabolite (10% of urinary /sup 75/Se and 3-4% of oral /sup 75/Se dose) at low dose levels of Se and for all three Se test compounds. At least 80% of urinary /sup 75/Se and 26-42% of the orally administered /sup 75/Se were excreted as non-TMSe Se metabolites in urine under the latter condition. It is hypothesized that at a requirement intake of Se either a trace or no TMSe is excreted in urine, and it becomes a major excretory metabolite of Se when the dietary trace mineral intake exceeds a requirement level, probably serving as a means of detoxification.

  6. Feeding and excretion in the Afghan pika (Ochotona rufescens rufescens), a new laboratory animal.

    PubMed

    Matsuzawa, T; Nakata, M; Tsushima, M

    1981-10-01

    Food and water intake and the excretion of urine and faecal pellets during the day (0500-2100) and at night (2100-0500) were observed in Afghan pikas, rats and guineapigs fed appropriate diets. Urine composition was observed in these species after they had been fed the pika diet for 4 weeks. Rats ate more at night than did pikas or guineapigs. The pikas excreted numerous small, hard faeces and soft faeces, the latter being reingested. On the pika diet all species gained about 10% in bodyweight. Food consumption was similar to that shown by each species on its own diet. All animals fed the pika diet excreted alkaline urine. Chloride concentration in pika urine was similar to that of the rat and was significantly higher than that of the guineapig. The ratio of sodium to potassium in pika urine was 2.8 and 1.7 fold that of the rat and guineapig respectively. Osmolality of pika urine was slightly higher than that of the rat, and was 3.8 fold that of the guineapig.

  7. Trichloroethylene exposure. Simulation of uptake, excretion, and metabolism using a mathematical model.

    PubMed Central

    Fernández, J G; Droz, P O; Humbert, B E; Caperos, J R

    1977-01-01

    The absorption, distribution, and excretion of trichloroethylene, as well as the kinetics of formation and elimination of trichloroethanol (TCE) and trichloroacetic acid (TCA) were simulated by a mathematical model. The results of this model have been satisfactorily compared with those obtained experimentally from pulmonary elimination of the solvent and from urinary excretion of the metabolites. The model permitted a study of the distribution of the solvent in the different tissues of the organism as well as an evaluation of the body burden of TCE and TCA. The influence of the duration and repetition of the exposure on the urinary eliminations of TCE and TCA was studied, and showed that the excretion of the first metabolite represents the most recent exposure while that of the second is related to the average exposure of the preceding days. The study of the pulmonary elimination of trichloroethylene during single or repeated exposures showed a linear relationship between the alveolar concentration of the solvent approximately 15 hours after the end of the exposure and the quantity of trichloroethylene accumulated in the fatty tissues. PMID:843463

  8. Defective roles of ATP7B missense mutations in cellular copper tolerance and copper excretion.

    PubMed

    Zhu, Min; Dong, Yi; Ni, Wang; Wu, Zhi-Ying

    2015-07-01

    Wilson's disease (WD) is a hereditary disorder of copper metabolism resulting from mutations within ATP7B. Clinical investigations showed that ATP7B missense mutations cause a wide variety of symptoms in WD patients, which implies that those mutations might affect ATP7B function in a number of ways and each would have deleterious consequences on normal copper distribution and lead to WD. Nonetheless, it is still unknown about the influences of those mutations on ATP7B function of increasing copper excretion and enhancing cellular copper tolerance. Here we established the stable expression cell lines of wild-type (WT) ATP7B and its four missense mutants (R778L, R919G, T935M and P992L), tested cellular copper tolerance and copper excretion using those cell lines, and also observed cellular distribution of WT ATP7B proteins and those mutants in transiently transfected cells. We found that extrinsic expressing WT ATP7B reduced CuCl2-induced copper accumulation and enhanced cellular copper tolerance by accelerating copper excretion, which was selectively compromised by R778L and P992L mutations. Further investigation showed that R778L mutation disrupted the subcellular localization and trafficking of ATP7B proteins, whereas P992L mutation only affected the trafficking of ATP7B. This indicates that ATP7B missense mutants have distinct effects on cellular copper tolerance.

  9. Oral intake of ranitidine increases urinary excretion of N-nitrosodimethylamine.

    PubMed

    Zeng, Teng; Mitch, William A

    2016-06-01

    The H2-receptor antagonist, ranitidine, is among the most widely used pharmaceuticals to treat gastroesophageal reflux disease and peptic ulcers. While previous studies have demonstrated that amines can form N-nitrosamines when exposed to nitrite at stomach-relevant pH, N-nitrosamine formation from ranitidine, an amine-based pharmaceutical, has not been demonstrated under these conditions. In this work, we confirmed the production of N-nitrosodimethylamine (NDMA), a potent carcinogen, by nitrosation of ranitidine under stomach-relevant pH conditions in vitro We also evaluated the urinary NDMA excretion attributable to ingestion of clinically used ranitidine doses. Urine samples collected from five female and five male, healthy adult volunteers over 24-h periods before and after consumption of 150mg ranitidine were analyzed for residual ranitidine, ranitidine metabolites, NDMA, total N-nitrosamines and dimethylamine. Following ranitidine intake, the urinary NDMA excreted over 24h increased 400-folds from 110 to 47 600ng, while total N-nitrosamines increased 5-folds. NDMA excretion rates after ranitidine intake equaled or exceeded those observed previously in patients with schistosomiasis, a disease wherein N-nitrosamines are implicated as the etiological agents for bladder cancer. Due to metabolism within the body, urinary NDMA measurements represent a lower-bound estimate of systemic NDMA exposure. Our results suggest a need to evaluate the risks attributable to NDMA associated with chronic consumption of ranitidine, and to identify alternative treatments that minimize exposure to N-nitrosamines. PMID:26992900

  10. Urinary excretion of zinc and metabolic control of patients with diabetes type 2.

    PubMed

    Marreiro, Dilina do Nascimento; do Perpetuo Socorro C Martins, Maria; de Sousa, Simone Sady Ribeiro; Ibiapina, Véritas; Torres, Silva; Pires, Liliane Viana; do Nascimento Nogueira, Nadir; Lima, José Maria Correia; do Monte, Semíramis Jamil Hadad

    2007-01-01

    The objective of this study was to assess urinary excretion of zinc and evaluation parameters of metabolic control in type 2 diabetic patients. Thirty-one type 2 diabetic patients, of both genders, with 5.8 +/- 5.6 years average time of the disease, age range 20-60 years, were selected. Evaluation of the nutritional status was performed using anthropometric measurements. To evaluate food consumption, the 3-day alimentary log method was used, and its analysis was performed using a software. Determination of urinary zinc was by atomic absorption spectrophotometry. From the obtained results, it was concluded that 51.6% of the patients were overweight. The mean of found waist circumference was 100.4 and 92.2 cm for men and women, respectively. Blood glucose and glycated hemoglobin values were higher than reference values, and plasma albumin concentration was adequate. The median of found urinary zinc excretion was 474.9 mug/24 h, within normal standards (300-600 mug/day). Regarding diet composition, calorie and protein concentration were above recommendation, while mean zinc concentration was adequate. This data allow the conclusion that the evaluated patients presented adequate urinary zinc excretion in comparison with reference values.

  11. Stereoselectivity in bioaccumulation and excretion of epoxiconazole by mealworm beetle (Tenebrio molitor) larvae.

    PubMed

    Lv, Xiaotian; Liu, Chen; Li, Yaobin; Gao, Yongxin; Wang, Huili; Li, Jianzhong; Guo, Baoyuan

    2014-09-01

    Stereoselectivity in bioaccumulation and excretion of stereoisomers of epoxiconazole by mealworm beetle (Tenebrio molitor) larvae through dietary exposure was investigated. Liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method that use a ChiralcelOD-3R[cellulosetris-Tris-(3, 5-dichlorophenyl-carbamate)] chromatography column was applied to carry out chiral separation of the stereoisomers. Wheat bran was spiked with racemic epoxiconazole at two dose levels of 20mg/kg and 2mg/kg (dry weight) to feed T. molitor larvae. The results showed that both the doses of epoxiconazole were taken up by Tenebrio molitor larvae rapidly at the initial stages. There was a significant trend of stereoselective bioaccumulation in the larvae with a preferential accumulation of (-)-epoxiconazole in the 20mg/kg dose. The stereoselectivity in bioaccumulation in the 2mg/kg dosage was not obvious compared to the 20mg/kg group. Results of excretion indicated an active excretion is an important pathway for the larvae to eliminate epoxiconazole which was a passive transport process with non stereoselectivity. The faster elimination might be the reason for the low accumulation of epoxiconazole, as measured by bioaccumulation factor (BAF). PMID:24907454

  12. Absorption, metabolism and excretion of 14C-sultopride in the rat.

    PubMed

    Dross, K; Sillmann, P; Küster, J

    1984-01-01

    Rats received (14C)-Sultopride (St) in doses of 20 mg/kg by ip. and oral route. After ip.-administration, urinary elimination was 62% of administered dose in 72 hours, fecal excretion, 25% in 96 hours. Conversely, at 120 hours after oral administration, renal elimination was 46% and fecal elimination 34%. From these data 75% absorption of St in rat intestine may be deduced. From total excreted radioactivity (feces plus urine; ip. route) 35% is due to unchanged St. Seven metabolites were isolated from the urine. By comparison of isolated compounds with chemically synthesized putative metabolites using spectrophotometric and radiometric TLC scanning procedures 5 metabolites were identified: O-desmethylated St (DMSt; 20% of total radioactivity excreted), sulfon-desethylated St (SDESt; 13%), 5-pyrrolidine-oxo St (OSt; 3%), the product of hydrolysis of the central amide bond (MESS; 4%) and the secondary metabolite O-desmethyl-oxo St (ODMST; less than 1%). Two metabolites both minor (1% or less), remained unidentified. In guinea-pigs, metabolism of St leads almost exclusively to OSt while in mice, to DMSt.

  13. Model for antiorthostatic hypokinesia - Head-down tilt effects on water and salt excretion

    NASA Technical Reports Server (NTRS)

    Deavers, D. R.; Musacchia, X. J.; Meininger, G. A.

    1980-01-01

    Water and electrolyte excretion was investigated in antiorthostatic hypokinetic and orthostatic hypokinetic and control rats in metabolic cages. Significant (t test, P less than 0.05) diuresis, natriuresis, and kaliuresis occurred in the antiorthostatic hypokinetic subjects but did not occur in either the orthostatic hypokinetic or controls. Recovery from antiorthostatic hypokinesia was characterized by retention of water, sodium, and potassium. Patterns of changes in body weight and food and water consumption were virtually identical in antiorthostatic and orthostatic hypokinetic rats and thus could not account for the differences in renal handling of water and electrolytes. Also, differences in ingestion of food and water in controls could not account for differences in excretion of water and electrolytes between these and antiorthostatic hypokinetic rats. It was concluded that the antiorthostatic position was responsible for the diuresis and natriuresis and that the antiorthostatic hypokinetic rat appears to be a good model for the study of water and elecrolyte excretion during conditions such as bed rest, water immersion, and exposure to weightlessness.

  14. Decreased nocturnal catecholamine excretion: parameter for an overtraining syndrome in athletes?

    PubMed

    Lehmann, M; Schnee, W; Scheu, R; Stockhausen, W; Bachl, N

    1992-04-01

    The effectiveness of high performance training should be examined at short intervals in order to recognize overtraining promptly. Field or laboratory tests can usually not be performed with such frequency. Easy-to-measure biological, training-relevant parameters are being sought to use in their place. Since the importance of the sympathetic nervous system for adaptation of stress and the relationship between physical training and the activity of the sympathetic nervous system are well accepted, and since an impairment of the sympathetic nervous system is assumed in an overtraining syndrome, we examined the relevance of nocturnal "basal" urinary excretion of free catecholamines with respect to its practical application: 1. during a pilot study (training of road and track cyclists before the 1988 Olympic Games in Seoul), 2. through a 4-week prospective, experimental study in 1989 and 1990 (middle- and long-distance runners), 3. during the competitive season and winter break of a soccer team between August 1990 and April 1991. The following hypothesis was made: An overtraining or exhaustion syndrome in athletes may usually be accompanied by at least a 50% decrease in basal dopamine, noradrenaline and adrenaline excretion. When training is effective or the athletes are not exhausted, the decrease of the excretion rate--with the exception of dopamine--is more likely to be lower (noradrenaline, adrenaline). Generalization of these results requires further expansion of the experimental basis. PMID:1601559

  15. Excretion of cytoplasmic proteins in Staphylococcus is most likely not due to cell lysis.

    PubMed

    Ebner, Patrick; Rinker, Janina; Götz, Friedrich

    2016-02-01

    The excretion of cytoplasmic proteins (ECP) is a long-known phenomenon in bacteria and eukaryotes. So far, it was not possible to associate either a signal peptide-dependent or a signal peptide-independent pathway to ECP. Nevertheless 25% of the proteins found in Staphylococcus aureus supernatants were cytoplasmic proteins. Because the excreted proteins do not possess a common motive, the most widespread opinion is that ECP is due to cell lysis. This explanation seems to be too easy since several indications imply that there exists a yet unknown mechanism for ECP. Certainly, the up-regulation of autolysins as well as decreased peptidoglycan cross-linking increased ECP. However, in recent years, several evidences arose that cell lysis is not the only reason for ECP. It seems that ECP is a part of the normal cell cycle of S. aureus as it turned out that ECP with several model proteins occurs mainly during cell growth. It has common features as proteins secreted via the Sec translocon and finally the excretion site is the cross wall of dividing cells.

  16. Collagen cross-link excretion during space flight and bed rest

    NASA Technical Reports Server (NTRS)

    Smith, S. M.; Nillen, J. L.; Leblanc, A.; Lipton, A.; Demers, L. M.; Lane, H. W.; Leach, C. S.; LeBlanc, A. (Principal Investigator)

    1998-01-01

    Extended exposure to weightlessness results in bone loss. However, little information exists as to the precise nature or time course of this bone loss. Bone resorption results in the release of collagen breakdown products, including N-telopeptide and the pyridinium (PYD) cross-links, pyridinoline and deoxypyridinoline. Urinary pyridinoline and deoxypyridinoline are known to increase during bed rest. We assessed excretion of PYD cross-links and N-telopeptide before, during, and after long (28-day, 59-day, and 84-day) Skylab missions, as well as during short (14-day) and long (119-day) bed-rest studies. During space flight, the urinary cross-link excretion level was twice those observed before flight. Urinary excretion levels of the collagen breakdown products were also 40-50% higher, during short and long bed rest, than before. These results clearly show that the changes in bone metabolism associated with space flight involve increased resorption. The rate of response (i.e. within days to weeks) suggests that alterations in bone metabolism are an early effect of weightlessness. These studies are important for a better understanding of bone metabolism in space crews and in those who are bedridden.

  17. Biological Monitoring of Human Exposure to Neonicotinoids Using Urine Samples, and Neonicotinoid Excretion Kinetics

    PubMed Central

    Harada, Kouji H.; Tanaka, Keiko; Sakamoto, Hiroko; Imanaka, Mie; Niisoe, Tamon; Hitomi, Toshiaki; Kobayashi, Hatasu; Okuda, Hiroko; Inoue, Sumiko; Kusakawa, Koichi; Oshima, Masayo; Watanabe, Kiyohiko; Yasojima, Makoto; Takasuga, Takumi; Koizumi, Akio

    2016-01-01

    Background Neonicotinoids, which are novel pesticides, have entered into usage around the world because they are selectively toxic to arthropods and relatively non-toxic to vertebrates. It has been suggested that several neonicotinoids cause neurodevelopmental toxicity in mammals. The aim was to establish the relationship between oral intake and urinary excretion of neonicotinoids by humans to facilitate biological monitoring, and to estimate dietary neonicotinoid intakes by Japanese adults. Methodology/Principal Findings Deuterium-labeled neonicotinoid (acetamiprid, clothianidin, dinotefuran, and imidacloprid) microdoses were orally ingested by nine healthy adults, and 24 h pooled urine samples were collected for 4 consecutive days after dosing. The excretion kinetics were modeled using one- and two-compartment models, then validated in a non-deuterium-labeled neonicotinoid microdose study involving 12 healthy adults. Increased urinary concentrations of labeled neonicotinoids were observed after dosing. Clothianidin was recovered unchanged within 3 days, and most dinotefuran was recovered unchanged within 1 day. Around 10% of the imidacloprid dose was excreted unchanged. Most of the acetamiprid was metabolized to desmethyl-acetamiprid. Spot urine samples from 373 Japanese adults were analyzed for neonicotinoids, and daily intakes were estimated. The estimated average daily intake of these neonicotinoids was 0.53–3.66 μg/day. The highest intake of any of the neonicotinoids in the study population was 64.5 μg/day for dinotefuran, and this was <1% of the acceptable daily intake. PMID:26731104

  18. Phytoplankton uptake and excretion of assimilated nitrate in a small Canadian shield lake.

    PubMed

    Chan, H K; Campbell, N E

    1978-06-01

    Nitrate uptake in the epilemnetic waters of a small eutrophic Canadian Shield lake was studied by using a 15N method during summer stratification. Concurrent with inhibition of primary production, 3-(3,4-dichlorophenyl)-1,1-dimethylurea inhibited NO3- assimilation. Nitrate up to 1 mg of N/liter did not affect the rate of primary production during 3 h of incubation. The NO3- fertilizer added to the lake weekly was consumed through algal assimilation in about 3 days. Excretion of the photoassimilated NO3- as dissolved organic nitrogen represented a significant portion of the nutrient incorporated by the cells. Only 40% of the NO3- -15N which disappeared could be accounted for in the particulate fraction. Although the rest was presumably excreted, only 15% of the 15N label was accounted for as cationic dissolved organic nitrogen by isotope assays. These excreted organic forms were predominantly serine and glycine in the dissolved free amino acid fraction. Bacteria as well as algae might be expected to contribute to and modify the extracellular nitrogen pool. PMID:677872

  19. Turnover and urinary excretion of free and acetylated MS-222 rainbow trout, Salmo gairdneri

    USGS Publications Warehouse

    Hunn, J.B.; Schoettger, R.A.; Willford, W.A.

    1968-01-01

    Rainbow trout (Salmo gairdneri) anesthetized in 100 mg/liter of M.S. 222 at 12 C excreted the drug in free and acetylated forms via the urine during a 24-hr recovery period in freshwater. Of the M.S. 222 excreted, 77-96% was acetylated. Blood levels of free drug in anesthetized trout approximated 75% of the anesthetic concentration, but the amount of acetylated M.S. 222 was relatively insignificant. The blood and urine were cleared of the two fractions of M.S. 222 in 8 and 24 hr respectively. Low levels of aromatic amines of natural origin occurred in blood and urine and were subtracted from measurements of M.S. 222. Intraperitoneal injections of 10-100 mg/kg of M.S. 222 did not induce anesthesia; however, the 24-hr pattern of drug excretion was similar to that observed after anesthesia by immersion. Only 15-21 % of the injected dose was found in the urine, suggesting a second route of drug elimination.

  20. Absorption, metabolism, and excretion of fermented orange juice (poly)phenols in rats.

    PubMed

    Escudero-López, Blanca; Calani, Luca; Fernández-Pachón, María-Soledad; Ortega, Angeles; Brighenti, Furio; Crozier, Alan; Del Rio, Daniele

    2014-01-01

    Two milliliters of a fermented, pasteurized orange juice containing ~1% alcohol and 2.3 μmol of (poly)phenolic compounds was fed to rats by gavage after which plasma and urine collected over a 36 h period were analyzed by UHPLC-mass spectrometry. The main constituents in the juice were hesperetin and naringenin-O-glycosides, apigenin-6,8-C-diglucoside, and ferulic acid-4'-O-glucoside. Plasma contained seven flavanone glucuronides, with the principal metabolites, naringenin-7-O-glucuronide, naringenin-4'-O-glucuronide, and an isosakuranetin-O-glucuronide, peaking 6 h after intake at concentrations of ~10 nmol/L. Urinary excretion of four hesperetin glucuronides was equivalent to 0.28% of intake while that of the two naringenin glucuronides was 2.8% of intake. The plasma and urine data suggest that while some absorption occurred in the small intestine, the main site of uptake was the colon. Urine also contained dihydroferulic acid-4'-O-glucuronide and dihydroferulic acid-4'-O-sulfate which were excreted in quantities corresponding to 48.2% of the ingested ferulic acid-4'-glucoside. This indicates that the hydroxycinnamate is much more bioavailable than the flavanones in the rat model. Conversion of the ferulic acid glucoside to the dihydroferulic acid metabolites involves the action of colonic microbial glycosidases and reductases/hydrogenases followed by postabsorption phase II metabolism before renal excretion.

  1. Bioaccumulation and excretion of enantiomers of myclobutanil in Tenebrio molitor larvae through dietary exposure.

    PubMed

    Lv, Xiaotian; Liu, Chen; Li, Yaobin; Gao, Yongxin; Guo, Baoyuan; Wang, Huili; Li, Jianzhong

    2013-12-01

    The bioaccumulation and excretion of enantiomers of myclobutanil in Tenebrio molitor larvae through dietary exposure under laboratory conditions were investigated using high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) based on a ChiralcelOD-3R [cellulosetris-tris-(3, 5-dichlorophenyl-carbamate)] column. The wheat bran fed to Tenebrio molitor larvae was spiked with racemic myclobutanil at two dose levels of 20 mg/kg and 2 mg/kg (dry weight). The results showed that there was a significant trend of enantioselective bioaccumulation in the larvae with a preferential accumulation of (-)-myclobutanil in 20 mg/kg dose exposure, but it was not obviously observed in the 2 mg/kg dose group. A kinetic model considering enantiomerization between the two enantiomers based on first-order reactions was built and the rate constants were estimated to discuss the kinetic reason for the different concentrations of individual enantiomers in the larvae. The approximations implied an inversion between the two enantiomers with a relatively higher rate of the inversion from (-)-myclobutanil to (+)-myclobutanil. Meanwhile, analysis of data of excretion samples suggested the active excretion is probably an important pathway for the insect to eliminate myclobutanil rapidly with nonenantioselectivity as a passive transport process, which was consistent with the low accumulation efficiency of myclobutanil measured by BAF (bioaccumulation factor).

  2. Stereoselectivity in bioaccumulation and excretion of epoxiconazole by mealworm beetle (Tenebrio molitor) larvae.

    PubMed

    Lv, Xiaotian; Liu, Chen; Li, Yaobin; Gao, Yongxin; Wang, Huili; Li, Jianzhong; Guo, Baoyuan

    2014-09-01

    Stereoselectivity in bioaccumulation and excretion of stereoisomers of epoxiconazole by mealworm beetle (Tenebrio molitor) larvae through dietary exposure was investigated. Liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method that use a ChiralcelOD-3R[cellulosetris-Tris-(3, 5-dichlorophenyl-carbamate)] chromatography column was applied to carry out chiral separation of the stereoisomers. Wheat bran was spiked with racemic epoxiconazole at two dose levels of 20mg/kg and 2mg/kg (dry weight) to feed T. molitor larvae. The results showed that both the doses of epoxiconazole were taken up by Tenebrio molitor larvae rapidly at the initial stages. There was a significant trend of stereoselective bioaccumulation in the larvae with a preferential accumulation of (-)-epoxiconazole in the 20mg/kg dose. The stereoselectivity in bioaccumulation in the 2mg/kg dosage was not obvious compared to the 20mg/kg group. Results of excretion indicated an active excretion is an important pathway for the larvae to eliminate epoxiconazole which was a passive transport process with non stereoselectivity. The faster elimination might be the reason for the low accumulation of epoxiconazole, as measured by bioaccumulation factor (BAF).

  3. Blood pressure, obesity and urine cation excretion in two populations of the Cook Islands.

    PubMed

    Katoh, K; Yamauchi, T; Hiraiwa, K

    1990-02-01

    As part of a physical anthropological and linguistic research in the Cook Islands, blood pressure levels, the degree of obesity, and urine cation excretion were measured in the residents of Rarotonga (the most westernized) and Mangaia (a less westernized island) in 1986. The rise of blood pressure with age was observed in both sexes in each island, with the mean systolic pressures of the oldest male group (155.8 vs. 137.3 mmHg) significantly higher, and those of older female groups (137.4 vs. 127.1 and 154.7 vs. 145.9 mmHg) relatively higher in Rarotonga than in Mangaia. The mean body mass index was much the same between the two islands, but mean skinfolds at triceps and subscapular sites were thicker in Rarotonga than in Mangaia in each sex and age group. The mean sodium to potassium excretion ratio fell with age (2.97 to 0.94 in males, 2.24 to 1.09 in females) in Rarotonga, and was consistently low (1.09 to 0.73) in Mangaia. Body mass index correlated with both systolic and diastolic pressures in each sex and island group but indeces of sodium excretion did not. Obesity was considered a more important risk factor for hypertension than sodium-intake in the surveyed population, and skinfolds, related to daily physical activity, probably associated with the difference in blood pressure levels observed between the two islands. PMID:2353347

  4. Pyridoxic acid excretion during low vitamin B-6 intake, total fasting, and bed rest

    NASA Technical Reports Server (NTRS)

    Coburn, S. P.; Thampy, K. G.; Lane, H. W.; Conn, P. S.; Ziegler, P. J.; Costill, D. L.; Mahuren, J. D.; Fink, W. J.; Pearson, D. R.; Schaltenbrand, W. E.

    1995-01-01

    Vitamin B-6 metabolism in 10 volunteers during 21 d of total fasting was compared with results from 10 men consuming a diet low only in vitamin B-6 (1.76 mumol/d) and with men consuming a normal diet during bed rest. At the end of the fast mean plasma concentrations of vitamin B-6 metabolites and urinary excretion of 4-pyridoxic acid tended to be higher in the fasting subjects than in the low-vitamin B-6 group. The fasting subjects lost approximately 10% of their total vitamin B-6 pool and approximately 13% of their body weight. The low-vitamin B-6 group lost only approximately 4% of their vitamin B-6 pool. Compared with baseline, urinary excretion of pyridoxic acid was significantly increased during 17 wk of bed rest. There was no increase in pyridoxic acid excretion during a second 15-d bed rest study. These data suggest the possibility of complex interactions between diet and muscle metabolism that may influence indexes that are frequently used to assess vitamin B-6 status.

  5. Absorption, distribution, metabolism and excretion of novel phosphodiesterase type 4 inhibitor ASP3258 in rats.

    PubMed

    Ohtsu, Yoshiaki; Sonoda, Takuya; Susaki, Yoko; Tohda, Toshifumi; Fukunaga, Yasuhisa; Iwatsubo, Takafumi; Noguchi, Kiyoshi

    2015-01-01

    The potent and selective phosphodiesterase 4 inhibitor ASP3258 is a novel therapeutic agent for asthma and chronic obstructive pulmonary disease (COPD). After a single oral administration to rats, ASP3258 is rapidly absorbed with a bioavailability of 106%. In situ absorption data indicated that ASP3258 is mainly absorbed in the small intestine. Tissue distribution data after oral administration of (14)C-ASP3258 showed rapid and extensive distribution to various tissues. Excluding the gastrointestinal tract, the tissues with the highest concentrations were liver, heart and plasma. Liquid chromatography-nuclear magnetic resonance spectroscopy data revealed that O-glucuronidation of the carboxylic acid moiety of ASP3258 (formation of an acyl glucuronide) plays a key role in metabolism. No indication was found that the acyl glucuronide reacted with proteins in plasma or tissues. When (14)C-ASP3258 was orally administered to intact rats, urinary and fecal excretion accounted for 1.3% and 100.6% of the administered radioactivity, respectively. After a single oral administration of (14)C-ASP3258 to bile-cannulated rats, urinary and biliary excretion accounted for 0.7% and 93.8% of the administered radioactivity, respectively. These findings suggest that fecal excretion via bile plays an important role in the elimination of ASP3258-derived radioactivity. In vitro metabolic profiles were relatively similar among the species examined, suggesting that our findings in rats may help us to understand pharmacokinetics, efficacy and safety profiles in humans and other species.

  6. Acute sterol o-acyltransferase 2 (SOAT2) knockdown rapidly mobilizes hepatic cholesterol for fecal excretion.

    PubMed

    Marshall, Stephanie M; Gromovsky, Anthony D; Kelley, Kathryn L; Davis, Matthew A; Wilson, Martha D; Lee, Richard G; Crooke, Rosanne M; Graham, Mark J; Rudel, Lawrence L; Brown, J Mark; Temel, Ryan E

    2014-01-01

    The primary risk factor for atherosclerotic cardiovascular disease is LDL cholesterol, which can be reduced by increasing cholesterol excretion from the body. Fecal cholesterol excretion can be driven by a hepatobiliary as well as a non-biliary pathway known as transintestinal cholesterol efflux (TICE). We previously showed that chronic knockdown of the hepatic cholesterol esterifying enzyme sterol O-acyltransferase 2 (SOAT2) increased fecal cholesterol loss via TICE. To elucidate the initial events that stimulate TICE, C57Bl/6 mice were fed a high cholesterol diet to induce hepatic cholesterol accumulation and were then treated for 1 or 2 weeks with an antisense oligonucleotide targeting SOAT2. Within 2 weeks of hepatic SOAT2 knockdown (SOAT2HKD), the concentration of cholesteryl ester in the liver was reduced by 70% without a reciprocal increase in hepatic free cholesterol. The rapid mobilization of hepatic cholesterol stores resulted in a ∼ 2-fold increase in fecal neutral sterol loss but no change in biliary cholesterol concentration. Acute SOAT2HKD increased plasma cholesterol carried primarily in lipoproteins enriched in apoB and apoE. Collectively, our data suggest that acutely reducing SOAT2 causes hepatic cholesterol to be swiftly mobilized and packaged onto nascent lipoproteins that feed cholesterol into the TICE pathway for fecal excretion.

  7. Acute Sterol O-Acyltransferase 2 (SOAT2) Knockdown Rapidly Mobilizes Hepatic Cholesterol for Fecal Excretion

    PubMed Central

    Marshall, Stephanie M.; Gromovsky, Anthony D.; Kelley, Kathryn L.; Davis, Matthew A.; Wilson, Martha D.; Lee, Richard G.; Crooke, Rosanne M.; Graham, Mark J.; Rudel, Lawrence L.

    2014-01-01

    The primary risk factor for atherosclerotic cardiovascular disease is LDL cholesterol, which can be reduced by increasing cholesterol excretion from the body. Fecal cholesterol excretion can be driven by a hepatobiliary as well as a non-biliary pathway known as transintestinal cholesterol efflux (TICE). We previously showed that chronic knockdown of the hepatic cholesterol esterifying enzyme sterol O-acyltransferase 2 (SOAT2) increased fecal cholesterol loss via TICE. To elucidate the initial events that stimulate TICE, C57Bl/6 mice were fed a high cholesterol diet to induce hepatic cholesterol accumulation and were then treated for 1 or 2 weeks with an antisense oligonucleotide targeting SOAT2. Within 2 weeks of hepatic SOAT2 knockdown (SOAT2HKD), the concentration of cholesteryl ester in the liver was reduced by 70% without a reciprocal increase in hepatic free cholesterol. The rapid mobilization of hepatic cholesterol stores resulted in a ∼2-fold increase in fecal neutral sterol loss but no change in biliary cholesterol concentration. Acute SOAT2HKD increased plasma cholesterol carried primarily in lipoproteins enriched in apoB and apoE. Collectively, our data suggest that acutely reducing SOAT2 causes hepatic cholesterol to be swiftly mobilized and packaged onto nascent lipoproteins that feed cholesterol into the TICE pathway for fecal excretion. PMID:24901470

  8. Recent advances in understanding trans-epithelial acid-base regulation and excretion mechanisms in cephalopods

    PubMed Central

    Hu, Marian Y; Hwang, Pung-Pung; Tseng, Yung-Che

    2015-01-01

    Cephalopods have evolved complex sensory systems and an active lifestyle to compete with fish for similar resources in the marine environment. Their highly active lifestyle and their extensive protein metabolism has led to substantial acid-base regulatory abilities enabling these organisms to cope with CO2 induced acid-base disturbances. In convergence to teleost, cephalopods possess an ontogeny-dependent shift in ion-regulatory epithelia with epidermal ionocytes being the major site of embryonic acid-base regulation and ammonia excretion, while gill epithelia take these functions in adults. Although the basic morphology and excretory function of gill epithelia in cephalopods were outlined almost half a century ago, modern immunohistological and molecular techniques are bringing new insights to the mechanistic basis of acid-base regulation and excretion of nitrogenous waste products (e.g. NH3/NH4+) across ion regulatory epithelia of cephalopods. Using cephalopods as an invertebrate model, recent findings reveal partly conserved mechanisms but also novel aspects of acid-base regulation and nitrogen excretion in these exclusively marine animals. Comparative studies using a range of marine invertebrates will create a novel and exciting research direction addressing the evolution of pH regulatory and excretory systems. PMID:26716070

  9. Renal excretion profiles of psilocin following oral administration of psilocybin: a controlled study in man.

    PubMed

    Hasler, Felix; Bourquin, Daniel; Brenneisen, Rudolf; Vollenweider, Franz X

    2002-09-01

    In a clinical study eight volunteers received psilocybin (PY) in psychoactive oral doses of 212+/-25 microg/kg body weight. To investigate the elimination kinetics of psilocin (PI), the first metabolite of PY, urine was collected for 24 h and PI concentrations were determined by high-performance liquid chromatography with column switching and electrochemical detection (HPLC-ECD). Sample workup included protection of the unstable PI with ascorbic acid, freeze-drying, and extraction with methanol. Peak PI concentrations up to 870 microg/l were measured in urine samples from the 2-4 h collection interval. The PI excretion rate in this period was 55.5+/-33.8 microg/h. The limit of quantitation (10 microg/L) was usually reached 24 h after drug administration. Within 24 h, 3.4+/-0.9% of the applied dose of PY was excreted as free PI. Addition of beta-glucuronidase to urine samples and incubation for 5 h at 40 degrees C led to twofold higher PI concentrations, although 18+/-7% of the amount of unconjugated PI was decomposed during incubation. We conclude that in humans PI is partially excreted as PI-O-glucuronide and that enzymatic hydrolysis extends the time of detectability for PI in urine samples.

  10. Phytoplankton uptake and excretion of assimilated nitrate in a small Canadian shield lake.

    PubMed

    Chan, H K; Campbell, N E

    1978-06-01

    Nitrate uptake in the epilemnetic waters of a small eutrophic Canadian Shield lake was studied by using a 15N method during summer stratification. Concurrent with inhibition of primary production, 3-(3,4-dichlorophenyl)-1,1-dimethylurea inhibited NO3- assimilation. Nitrate up to 1 mg of N/liter did not affect the rate of primary production during 3 h of incubation. The NO3- fertilizer added to the lake weekly was consumed through algal assimilation in about 3 days. Excretion of the photoassimilated NO3- as dissolved organic nitrogen represented a significant portion of the nutrient incorporated by the cells. Only 40% of the NO3- -15N which disappeared could be accounted for in the particulate fraction. Although the rest was presumably excreted, only 15% of the 15N label was accounted for as cationic dissolved organic nitrogen by isotope assays. These excreted organic forms were predominantly serine and glycine in the dissolved free amino acid fraction. Bacteria as well as algae might be expected to contribute to and modify the extracellular nitrogen pool.

  11. Biliary excretion of radioactivity after intravenous administration of (3H)25-hydroxyvitamin D3 in man

    SciTech Connect

    Ledger, J.E.; Watson, G.J.; Compston, J.E.

    1986-04-01

    The biliary excretion of radioactivity after intravenous (3H)25-hydroxyvitamin D3 was studied in nine patients with T-tube bile drainage. The mean +/- SD 24-hr radioactivity excretion in T-tube bile expressed as a percentage of the administered dose was 6.7 +/- 2.9%; after correction for incomplete bile collection, the value obtained was 16.0 +/- 11.1%. Chloroform solubility of biliary radioactivity increased from 27.4 +/- 8.9% to 72.9 +/- 10.1% following incubation with beta-glucuronidase. High-performance liquid chromatographic analysis of chloroform extracts of bile revealed that most of the eluted radioactivity was more polar than (3H)25-hydroxyvitamin D3. No free (3H)25-hydroxyvitamin D3 was demonstrated. Thus in man, most of the biliary radioactivity excreted following (3H)25-hydroxyvitamin D3 is in the form of water-soluble compounds, mainly glucuronides. However, our results suggest that glucuronides of metabolites other than 25-OHD3 are predominantly formed.

  12. Recent advances in understanding trans-epithelial acid-base regulation and excretion mechanisms in cephalopods.

    PubMed

    Hu, Marian Y; Hwang, Pung-Pung; Tseng, Yung-Che

    2015-01-01

    Cephalopods have evolved complex sensory systems and an active lifestyle to compete with fish for similar resources in the marine environment. Their highly active lifestyle and their extensive protein metabolism has led to substantial acid-base regulatory abilities enabling these organisms to cope with CO2 induced acid-base disturbances. In convergence to teleost, cephalopods possess an ontogeny-dependent shift in ion-regulatory epithelia with epidermal ionocytes being the major site of embryonic acid-base regulation and ammonia excretion, while gill epithelia take these functions in adults. Although the basic morphology and excretory function of gill epithelia in cephalopods were outlined almost half a century ago, modern immunohistological and molecular techniques are bringing new insights to the mechanistic basis of acid-base regulation and excretion of nitrogenous waste products (e.g. NH3/NH4 (+)) across ion regulatory epithelia of cephalopods. Using cephalopods as an invertebrate model, recent findings reveal partly conserved mechanisms but also novel aspects of acid-base regulation and nitrogen excretion in these exclusively marine animals. Comparative studies using a range of marine invertebrates will create a novel and exciting research direction addressing the evolution of pH regulatory and excretory systems.

  13. Cortisol-mediated synchronization of circadian rhythm in urinary potassium excretion

    NASA Technical Reports Server (NTRS)

    Moore-Ede, M. C.; Schmelzer, W. S.; Kass, D. A.; Herd, J. A.

    1977-01-01

    Conscious chair-acclimatized squirrel monkeys (Saimiri sciureus) studied with lights on (600 lx) from 0800 to 2000 hr daily (LD 12:12) display a prominent circadian rhythm in renal potassium excretion. The characteristics of this rhythm were reproduced in adrenalectomized monkeys by infusing 5 mg cortisol and 0.001 mg aldosterone, or 5 mg cortisol alone, between 0800 and 0900 kr daily. When the timing of cortisol administration (with or without aldosterone) was phase-delayed by 8 hr, the urinary potassium rhythm resynchronized by 80% of the cortisol phase shift, but only after a transient response lasting 3-4 days. With the same daily dose of adrenal steroids given as a continuous infusion throughout each 24 hr, urinary potassium excretion showed free-running oscillations no longer synchronized to the light-dark cycle. These results indicate that the circadian rhythm of plasma cortisol concentration acts as an internal mediator in the circadian timing system, synchronizing a potentially autonomous oscillation in renal potassium excretion to environmental time cues and to other circadian rhythms within the animal.

  14. Circadian rhythm of water balance and aldosterone excretion in the whitebellied sunbird Nectarinia talatala.

    PubMed

    Fleming, P A; Gray, D A; Nicolson, S W

    2004-05-01

    Nectarivorous whitebellied sunbirds, Nectarinia talatala, demonstrate distinct circadian patterns in osmoregulatory parameters. We recorded intake of a 1 mol/l sucrose solution which enabled calculation of total water gain, and collected cloacal fluid for measurements of volume, osmolality and aldosterone concentration. These variables were assessed hourly over 12 h of photophase, and averaged over the 12-h scotophase period. Overnight, when sunbirds were in negative water balance, aldosterone concentrations and outputs were significantly higher than diurnal levels, reflecting a shut-down of cloacal fluid production. Early morning was marked by a high rate of osmotic excretion, disproportionate to water gain or cloacal fluid output, followed by steady intake and cloacal fluid output during the morning and early afternoon. Reduced water flux (decreased feeding and cloacal fluid output) during mid-afternoon was accompanied by a paradoxical decline in osmotic excretion, whilst a significant increase in the discrepancy between water intake and output was recorded as the birds effectively stored water before the scotophase. These patterns of intake and excretion may be informative in explaining drinking and foraging behaviour in the field.

  15. Extremely low level of Ag nanoparticle excretion from mice brain in in vivo experiments

    NASA Astrophysics Data System (ADS)

    Antsiferova, A.; Buzulukov, Yu; Demin, V.; Kashkarov, P.; Kovalchuk, M.; Petritskaya, E.

    2015-11-01

    Silver nanoparticle accumulation in mice organs as well as the excretion processes from them were studied. The investigation included a one-time oral administration of silver nanoparticles and a series of prolonged oral administrations of the same nanoparticles to study the long-term impact of the nanoparticles. In these experiments, the mice had been fed with colloid silver and in these prolonged experiments, administrations lasted for 2 months. The nanoparticle administration was then cancelled for one month. The elemental composition of tissue samples was studied by Nuclear Physical technique, which allowed us to obtain the masses of the key element, namely silver. It was demonstrated that silver concentrations in tissues were redistributed with time. The main result of this work was the discovery of extremely low level of silver nanoparticle excretion from mice brain (just 6% per month) following the cancellation of NP administration. However, the rates of excretion from blood and liver appeared to be rather high (about 80% per month). Thus, the accumulation effect of silver nanoparticles in the mice brain was observed, which is of great practical importance. It changes the approach to the toxicity assessment of silver nanoparticles as a result of the prolonged injection of colloidal silver.

  16. Absorption and excretion of 1-amino-2-naphthol-6-sulphonic acid in rats and rabbits.

    PubMed

    Larsen, J C; Tarding, F

    1978-01-01

    1-amino-2-naphthol-6-sulphonic acid (ANSA) and compounds of similar structure are metabolites formed by azo reduction in mammals from several commonly used food colours, e.g. Sunset Yellow FCF and Food Red 17. At our institute it has been shown that ANSA produces bile duct proliferation when given orally to rabbits. Furthermore Orange RN which by azo reduction yields ANSA (and aniline) induce the same effect in pigs (Olsen et al., 1973) but not in rats (Gaunt et al., 1971). Using 35S-labelled ANSA the absorption and excretion as well as the localisation in the liver cell of ANSA was investigated in rats and rabbits. The results after p.o. administration shows that the rabbit absorbs and excretes into the urine a significant larger amount of ANSA (30-40%) than the rat (6-13%). The results after i.v. administration shows that some 60% of the injected dose is excreted in the urine in both species. In the rat 15-20% are recovered from the faeces, while only traces (0.1-0.5%) are found in faeces of rabbits. A significant amount of ANSA was retained in the blood and the liver of both species 24 and 48 hours after administration. After differential centrifugation of liver homogenates the majority of ANSA was found in the 9000 x g supernatant.

  17. Effect of a prostacyclin analogue, iloprost, on urinary aquaporin-2 excretion in humans.

    PubMed

    Buemi, Michele; Di Pasquale, Giuseppe; Ruello, Antonella; Floccari, Fulvio; Aloisi, Carmela; Latassa, Giuseppe; Corsonello, Andrea; Sturiale, Alessio; Corica, Francesco; Frisina, Nicola

    2002-06-01

    The regulation of aquaporin-2 (AQP2) water channel excretion in the collecting duct depends mainly on the action of vasopressin (AVP). Recently, however, other regulatory factors have been identified: atrial natriuretic factor, oxytocin and prostaglandins. In healthy volunteers (5 males, 5 females; mean age 23 +/- 3 years) we therefore evaluated the effect of a stable analogue of prostacyclin-2 (PGI(2)), iloprost, on renal function and on the urinary excretion of AQP2 (U-AQP2). After 6 h of iloprost infusion, U-AQP2 increased from 0.8 +/- 0.15 to 1.8 +/- 0.2 pmol/mg creatinine (p < 0.001), while the urinary flow rate increased from 1.4 +/- 0.2 to 1.8 +/- 4 (p < 0.01). No significant change was found in the AVP serum concentration, with a basal value of 3.17 +/- 0.12 vs. 3.15 +/- 0.12 pg/ml after 6 h of prostacyclin infusion. All the values returned to pre-study levels after a recovery period of 6 h. In conclusion, the PGI(2) analogue, iloprost, can induce U-AQP2 excretion independent of AVP.

  18. Factors Associated With High Sodium Intake Based on Estimated 24-Hour Urinary Sodium Excretion

    PubMed Central

    Hong, Jae Won; Noh, Jung Hyun; Kim, Dong-Jun

    2016-01-01

    Abstract Although reducing dietary salt consumption is the most cost-effective strategy for preventing progression of cardiovascular and renal disease, policy-based approaches to monitor sodium intake accurately and the understanding factors associated with excessive sodium intake for the improvement of public health are lacking. We investigated factors associated with high sodium intake based on the estimated 24-hour urinary sodium excretion, using data from the 2009 to 2011 Korea National Health and Nutrition Examination Survey (KNHANES). Among 21,199 adults (≥19 years of age) who participated in the 2009 to 2011 KNHANES, 18,000 participants (weighted n = 33,969,783) who completed urinary sodium and creatinine evaluations were analyzed in this study. The 24-hour urinary sodium excretion was estimated using Tanaka equation. The mean estimated 24-hour urinary sodium excretion level was 4349 (4286–4413) mg per day. Only 18.5% (weighted n = 6,298,481/3,396,973, unweighted n = 2898/18,000) of the study participants consumed less the 2000 mg sodium per day. Female gender (P < 0.001), older age (P < 0.001), total energy intake ≥50 percentile (P < 0.005), and obesity (P < 0.001) were associated with high sodium intake, even after adjusting for potential confounders. Senior high school/college graduation in education and managers/professionals in occupation were associated with lower sodium intake (P < 0.001). According to hypertension management status, those who had hypertension without medication consumed more sodium than those who were normotensive. However, those who receiving treatment for hypertension consumed less sodium than those who were normotensive (P < 0.001). The number of family members, household income, and alcohol drinking did not affect 24-hour urinary sodium excretion. The logistic regression analysis for the highest estimated 24-hour urinary sodium excretion quartile (>6033 mg/day) using the

  19. Excretion of sterols from the skin of normal and hypercholesterolemic humans

    PubMed Central

    Bhattacharyya, Ashim K.; Connor, William E.; Spector, Arthur A.

    1972-01-01

    The 24 hr sterol excretion from the entire skin surface was determined in six normal and five hypercholesterolemic (Type II) patients fed a controlled, eucaloric diet containing 400 mg of plant sterols. All subjects received radiolabeled cholesterol intravenously in order to measure cholesterol turnover and exchange. The 24 hr skin surface lipids were collected subsequently at intervals of 7-10 days. Sterols were quantified and identified by a combination of thin-layer and gas-liquid chromatographic methods. The mean 24 hr excretion of cholesterol in milligrams was 82.6 in the normal subjects and 82.7 in the hypercholesterolemic patients. Cholesterol constituted 89% of the total sterol excretion through the skin surface in both groups. The specific radioactivity of cholesterol in the skin surface lipids increased gradually after the intravenous administration of the isotope. Within 4-5 wk the specific activity equaled and then remained higher than that of the plasma up to 10 wk. These specific activity curves suggested that, for at least some of skin surface cholesterol, there was a precursor-product relationship between the plasma cholesterol and the skin cholesterol. The presence of plant sterols, β-sitosterol, campesterol, and stigmasterol in the skin surface lipids of man has not been reported previously. We identified these sterols in the skin surface lipids of all of our subjects. They constituted about 7% of the total skin surface sterols. The occurrence of plant sterols in the skin surface lipids suggested that plasma sterols were transferred from the plasma into the skin. 1-2% of the skin surface sterols were tentatively identified as lathosterol and lanosterol. The present study documented that a significant amount of cholesterol was excreted from the skin surface and that probably there was a net transfer of plasma cholesterol into the skin surface lipids. Both normal subjects and hypercholesterolemic patients excreted similar amounts of cholesterol per

  20. Catecholamine excretion and circadian blood pressure profile in patients with pheochromocytoma.

    PubMed

    Dabrowska, Elzbieta; Lewandowski, Jacek; Jedrusik, Piotr; Symonides, Bartosz; Wocial, Bozena; Lapinski, Mariusz; Gaciong, Zbigniew

    2006-08-01

    Circadian blood pressure (BP) rhythm is often disturbed in patients with secondary forms of hypertension. The aim of the present article was to investigate changes in circadian BP profile parameters using two-step statistical approach by Fourier analysis in relation to day and night urinary catecholamine excretion in 35 patients with pheochromocytoma (mean age 42+/-19 years). Twenty-four-hour ambulatory BP measurements (ABPM) were obtained using the SpaceLabs 90,207 monitor. Daytime and night-time urine collection was obtained in all patients to determine circadian catecholamine excretion. Fourier analysis was applied to estimate measures of BP circadian rhythm in ABPM, including the highest (Max) and lowest (Min) systolic (SBP) and diastolic (DBP) BP values, norad (ampSBP, ampDBP), and early acrophase (APSBP, APDBP). The Fourier indices of circadian BP rhythm were: MaxSBP 153+/-28 mm Hg, MaxDBP 99+/-16 mm Hg, MinSBP 117+/-17 mm Hg, MinDBP 69+/-11 mm Hg, ampSBP 18+/-8 mm Hg, ampDBP 14+/-5 mm Hg, APSBP 10+/-5 (h), and APDBP 11+/-3 (h). Urine noradrenaline (NA), adrenaline (A), and dopamine (DA) excretion during the day (d) and night (n) were: dNA 103.5+/-89.8 microg/14 h, nNA 52+/-70.8 microg/10 h, dA 13.2+/-17.9 microg/14 h; nA 6.13+/-9.6 microg/10 h, dD 181.8+/-87.3 microg/14 h, and nD 89.3+/-59.8 microg/10 h. A positive correlation was observed between urine dNa excretion and MaxDBP (r=0.37, P<0.05), and urine nNA and urine dA excretion were correlated with APDBP (r=0.47, r=0.35, respectively, both P<0.05). Thus, in addition to the effect on mean 24-h BP values, catecholamines released by tumor may also disturb circadian BP rhythm in patients with pheochromocytoma. PMID:17102074

  1. Bicarbonate promotes BK-α/β4-mediated K excretion in the renal distal nephron.

    PubMed

    Cornelius, Ryan J; Wen, Donghai; Hatcher, Lori I; Sansom, Steven C

    2012-12-01

    Ca-activated K channels (BK), which are stimulated by high distal nephron flow, are utilized during high-K conditions to remove excess K. Because BK predominantly reside with BK-β4 in acid/base-transporting intercalated cells (IC), we determined whether BK-β4 knockout mice (β4KO) exhibit deficient K excretion when consuming a high-K alkaline diet (HK-alk) vs. high-K chloride diet (HK-Cl). When wild type (WT) were placed on HK-alk, but not HK-Cl, renal BK-β4 expression increased (Western blot). When WT and β4KO were placed on HK-Cl, plasma K concentration ([K]) was elevated compared with control K diets; however, K excretion was not different between WT and β4KO. When HK-alk was consumed, the plasma [K] was lower and K clearance was greater in WT compared with β4KO. The urine was alkaline in mice on HK-alk; however, urinary pH was not different between WT and β4KO. Immunohistochemical analysis of pendrin and V-ATPase revealed the same increases in β-IC, comparing WT and β4KO on HK-alk. We found an amiloride-sensitive reduction in Na excretion in β4KO, compared with WT, on HK-alk, indicating enhanced Na reabsorption as a compensatory mechanism to secrete K. Treating mice with an alkaline, Na-deficient, high-K diet (LNaHK) to minimize Na reabsorption exaggerated the defective K handling of β4KO. When WT on LNaHK were given NH(4)Cl in the drinking water, K excretion was reduced to the magnitude of β4KO on LNaHK. These results show that WT, but not β4KO, efficiently excretes K on HK-alk but not on HK-Cl and suggest that BK-α/β4-mediated K secretion is promoted by bicarbonaturia.

  2. A pilot study on the urinary excretion of porphyrins in human populations chronically exposed to arsenic in Mexico.

    PubMed

    García-Vargas, G G; García-Rangel, A; Aguilar-Romo, M; García-Salcedo, J; del Razo, L M; Ostrosky-Wegman, P; Cortinas de Nava, C; Cebrián, M E

    1991-05-01

    1 The aim of this pilot study was to investigate if the porphyrinuria produced by arsenic in rodents was present in humans chronically exposed to arsenic via drinking water. 2 The concentrations of uroporphyrin, coproporphyrin and total arsenic in urine were compared between 21 individuals exposed to arsenic in their drinking water (0.390 mg l-1) and 19 controls exposed to 0.012 mg l-1. 3 Arsenic-exposed individuals had significantly higher total arsenic concentrations in their urine than the control group. No increase in urinary porphyrin excretion was found in exposed individuals. However, an inversion of the coproporphyrin/uroporphyrin (COPRO/URO) ratio was observed in most exposed individuals. This inversion was caused both, by a decrease in coproporphyrin excretion and an increase in uroporphyrin excretion. 4 No demonstrable correlations between porphyrin excretion, the COPRO/URO ratio and total arsenic concentration in urine were found in exposed individuals.

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

    EPA Science Inventory

    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...

  4. Prolonged excretion of a low-pathogenicity H5N2 avian influenza virus strain in the Pekin duck

    PubMed Central

    Carranza-Flores, José Manuel; Padilla-Noriega, Luis; Loza-Rubio, Elizabeth

    2013-01-01

    H5N2 strains of low-pathogenicity avian influenza virus (LPAIV) have been circulating for at least 17 years in some Mexican chicken farms. We measured the rate and duration of viral excretion from Pekin ducks that were experimentally inoculated with an H5N2 LPAIV that causes death in embryonated chicken eggs (A/chicken/Mexico/2007). Leghorn chickens were used as susceptible host controls. The degree of viral excretion was evaluated with real-time reverse transcriptase-polymerase chain reaction (RRT-PCR) using samples from oropharyngeal and cloacal swabs. We observed prolonged excretion from both species of birds lasting for at least 21 days. Prolonged excretion of LPAIV A/chicken/Mexico/2007 is atypical. PMID:23820212

  5. Evaluation of Salt Intake, Urinary Sodium Excretion and Their Relationship to Overhydration in Chronic Kidney Disease Patients.

    PubMed

    Hallvass, Andrea E C; Claro, Lígia Maria; Gonçalves, Simone; Olandoski, Márcia; Nerbass, Fabiana Baggio; Aita, Carlos Alberto Mayora; de Moraes, Thyago Proença; Pecoits-Filho, Roberto

    2015-01-01

    The purpose of this study was to estimate sodium intake in a group of patients with chronic kidney disease (CKD) and to correlate the results with the urinary excretion values of sodium and signs of fluid overload. We included patients with CKD in different stages. Urinary sodium was measured in 24 h urine samples. Body composition monitor (BCM) was used to estimate the hydration status. Sixty patients (38 ± 15 ml/min of GFR) presented 4.14 ± 1.71 g/24 h of urinary sodium excretion. Overhydration was detected in 50% of the patients by the BCM. There was a positive correlation between the measured sodium excretion values and BCM, ICW, ECW and TBW. In conclusion, markers of overhydration evaluated by BCM were positively correlated with urinary sodium excretion.

  6. Zea mays L. extracts modify glomerular function and potassium urinary excretion in conscious rats.

    PubMed

    Velazquez, D V O; Xavier, H S; Batista, J E M; de Castro-Chaves, C

    2005-05-01

    Diuretic and uricosuric properties have traditionally been attributed to corn silk, stigma/style of Zea mays L. Although the diuretic effect was confirmed, studies of the plant's effects on renal function or solute excretion were lacking. Thus, we studied the effects of corn silk aqueous extract on the urinary excretion of water, Na+, K+, and uric acid. Glomerular and proximal tubular function and Na+ tubular handling were also studied. Conscious, unrestrained adult male rats were housed in individual metabolic cages (IMC) with continuous urine collection for 5 and 3 h, following two protocols. The effects of 25, 50, 200, 350, and 500 mg/kg body wt. corn silk extract on urine volume plus Na+ and K+ excretions were studied in water-loaded conscious rats (2.5 ml/100 g body wt.) in the IMC for 5 h (Protocol 1). Kaliuresis was observed with doses of 350 (100.42 +/- 22.32-120.28 +/- 19.70 microEq/5 h/100 g body wt.; n = 13) and 500 mg/kg body wt. (94.97+/- 29.30-134.32 +/- 39.98 microEq/5h/100 g body wt.; n = 12; p<0.01), and the latter dose resulted in diuresis as well (1.98 +/- 0.44-2.41 +/- 0.41 ml/5 h/100 g body wt.; n = 12; p<0.05). The effects of a 500 mg/kg body wt. dose of corn silk extract on urine volume, Na+, K+ and uric acid excretions, and glomerular and proximal tubular function, were measured respectively by creatinine (Cler) and Li+ (ClLi) clearances and Na+ tubular handling, in water-loaded rats (5 ml/100 g body wt.) in the IMC for 3 h (Protocol 2). Clcr (294.6 +/- 73.2, n = 12, to 241.7 +/- 48.0 microl/ min/100 g body wt.; n = 13; p<0.05) and the Na+ filtered load (41.9 +/- 10.3, n = 12, to 34.3 +/- .8, n = 13, p<0.05) decreased and ClLi and Na+ excretion were unchanged, while K+ excretion (0.1044 +/- 0.0458, n=12, to 0.2289 +/- 0.0583 microEq/min/100 body wt.; n = 13; p<0.001) increased. For Na+ tubular handling, the fractional proximal tubular reabsorption (91.5 +/- 3.5, n = 12, to 87.5 +/- 3.4%; n = 13; p<0.01) decreased, and both fractional distal

  7. Validation and Assessment of Three Methods to Estimate 24-h Urinary Sodium Excretion from Spot Urine Samples in Chinese Adults

    PubMed Central

    Peng, Yaguang; Li, Wei; Wang, Yang; Chen, Hui; Bo, Jian; Wang, Xingyu; Liu, Lisheng

    2016-01-01

    24-h urinary sodium excretion is the gold standard for evaluating dietary sodium intake, but it is often not feasible in large epidemiological studies due to high participant burden and cost. Three methods—Kawasaki, INTERSALT, and Tanaka—have been proposed to estimate 24-h urinary sodium excretion from a spot urine sample, but these methods have not been validated in the general Chinese population. This aim of this study was to assess the validity of three methods for estimating 24-h urinary sodium excretion using spot urine samples against measured 24-h urinary sodium excretion in a Chinese sample population. Data are from a substudy of the Prospective Urban Rural Epidemiology (PURE) study that enrolled 120 participants aged 35 to 70 years and collected their morning fasting urine and 24-h urine specimens. Bias calculations (estimated values minus measured values) and Bland-Altman plots were used to assess the validity of the three estimation methods. 116 participants were included in the final analysis. Mean bias for the Kawasaki method was -740 mg/day (95% CI: -1219, 262 mg/day), and was the lowest among the three methods. Mean bias for the Tanaka method was -2305 mg/day (95% CI: -2735, 1875 mg/day). Mean bias for the INTERSALT method was -2797 mg/day (95% CI: -3245, 2349 mg/day), and was the highest of the three methods. Bland-Altman plots indicated that all three methods underestimated 24-h urinary sodium excretion. The Kawasaki, INTERSALT and Tanaka methods for estimation of 24-h urinary sodium excretion using spot urines all underestimated true 24-h urinary sodium excretion in this sample of Chinese adults. Among the three methods, the Kawasaki method was least biased, but was still relatively inaccurate. A more accurate method is needed to estimate the 24-h urinary sodium excretion from spot urine for assessment of dietary sodium intake in China. PMID:26895296

  8. Ingestion of chromium(VI) in drinking water by human volunteers: Absorption, distribution, and excretion of single and repeated doses

    SciTech Connect

    Kerger, B.D.; Corbett, G.E.; Dodge, D.G.

    1997-01-01

    This study examines the magnitude of hexavalent chromium [Cr(VI)] absorption, distribution, and excretion following oral exposure to 5 and 10 mg Cr(VI)/L in drinking water administered as a single bolus dose or for 3 d at a dosage of 1 L/d. Adult male volunteers were used. In the bolus dose studies, a fairly consistent pattern of urinary chromium excretion was observed, with an average half life of about 39 h. However, 4-d total urinary chromium excretion and peak concentrations in urine and blood varied considerably among the 5 volunteers. Studies of repeated exposure to small volumes ingested at a more gradual rate showed similar urinary chromium excretion patterns but generally lower chromium uptake/excretion. These data suggest that virtually all of the ingested Cr(VI) at 5 and 10 mg Cr(VI)/L was reduced to Cr(III) before entering the bloodstream. The interindividual differences in total chromium uptake and excretion are plausibly explained by ingestion of appreciable doses on an empty stomach, likely results in the formation of well-absorbed Cr(III) organic complexes. No clinical indications of toxicity in the volunteers and the patterns of blood uptake and urinary excretion of chromium are consistent with a predominant uptake of Cr(III) organic complexes that are excreted more slowly than inorganic forms of Cr(III). Therefore, it appears that the endogenous reducing agents within the upper gastrointestinal tract and the blood provide sufficient reducing potential to prevent any substantial systemic uptake of Cr(VI) following drinking-water exposures at 5-10 mg Cr(VI)/L. Based on these data, the chemical environment in the gastrointestinal tract and the blood is effective even under relative fasting condition in reducing Cr(VI) to one or more forms of Cr(III). 54 refs., 5 figs., 1 tab.

  9. Comparison of the biliary excretion of the four isomers of bilirubin-IX in Wistar and homozygous Gunn rats.

    PubMed Central

    Blanckaert, N; Heirwegh, K P; Zaman, Z

    1977-01-01

    The biliary excretion of the four isomers of bilirubin-IX was studied in Wistar rats (JJ) and homozygous Gunn rats (jj). Synthetic preparations of 14C-labelled pigments were used. 1. After intravenous administration, the alpha-isomer was rapidly excreted in conjugated form in bile of Wistar rats. In Gunn rats excretion was insignificant. In contrast, both rat species promptly excreted the non-alpha-isomers at rates that were comparable with that found for bilirubin-IXalpha in Wistar rats. 2. In normal rats about 16% of the beta- and delta-isomers and at least 50% of the gamma-isomer were excreted as ester conjugates of the injected parent bile pigments. Conjugation of the beta- and delta-isomers had occurred exclusively at the carboxyl groups of pyrrole ring D and C respectively. For bilirubin-IXgamma no preference for any carboxyl group could be established. 3. In homozygous Gunn rats the non-alpha-isomers were apparently excreted chemically unaltered. This suggests that, as for bilirubin-IXalpha, conjugation of the non-alpha-isomers is also deficient in Gunn rats. PMID:880229

  10. Human urinary excretion profile after smoking and oral administration of ( sup 14 C)delta 1-tetrahydrocannabinol

    SciTech Connect

    Johansson, E.; Gillespie, H.K.; Halldin, M.M. )

    1990-05-01

    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 ({sup 14}C)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 {sup 14}C-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 {sup 14}C-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.

  11. Effect of metoprolol on 24-hour urinary excretion of adrenal steroids and kallikrein in patients with essential hypertension.

    PubMed Central

    Fritschka, E.; Gotzen, R.; Kittler, R.; Schöneshöfer, M.

    1984-01-01

    Treatment of fifteen patients with essential hypertension over four weeks using the beta 1-adrenoceptor blocking agent, metoprolol, resulted in a decrease in 24 h urinary excretion of kallikrein and aldosterone along with a decrease in plasma renin activity. There was no significant change in 24 h excretion rates of the free adrenal steroids deoxycorticosterone, 18-OH-deoxycorticosterone, corticosterone, cortisol or 18-OH-corticosterone during treatment, which were not significantly different from excretion rates of normal males, thus excluding inhibitory effects of adrenal steroids on urinary kallikrein activity. A positive correlation was found between plasma renin activity and urinary excretion of kallikrein during the control period and after 2 weeks on metoprolol, supporting the assumption of a preserved link between the renin-angiotensin-aldosterone system and the renal excretion of kallikrein in these patients. The decrease in kallikrein excretion during beta 1-adrenoceptor blockade in patients with essential hypertension may be explained by a reduction in sympathetic tone and by reduced activity of the renin-aldosterone system. PMID:6367871

  12. Inductively coupled plasma mass-spectrometric determination of platinum in excretion products of client-owned pet dogs.

    PubMed

    Janssens, T; Brouwers, E E M; de Vos, J P; de Vries, N; Schellens, J H M; Beijnen, J H

    2015-06-01

    Residues of antineoplastic drugs in canine excretion products may represent exposure risks to veterinary personnel, owners of pet dogs and other animal care-takers. The aim of this study was to measure the extent and duration of platinum (Pt) excretion in pet dogs treated with carboplatin. Samples were collected before and up to 21 days after administration of carboplatin. We used validated, ultra-sensitive, inductively coupled plasma-mass spectrometry assays to measure Pt in canine urine, faeces, saliva, sebum and cerumen. Results showed that urine is the major route of elimination of Pt in dogs. In addition, excretion occurs via faeces and saliva, with the highest amounts eliminated during the first 5 days. The amount of excreted Pt decreased over time but was still quantifiable at 21 days after administration of carboplatin. In conclusion, increased Pt levels were found in all measured excretion products up to 21 days after administration of carboplatin to pet dogs, with urine as the main route of excretion. These findings may be used to further adapt current veterinary guidelines on safe handling of antineoplastic drugs and treated animals. PMID:23714139

  13. Bilary and urinary excretion of five cardiac glycosides and its correlation with their physical and chemical properties.

    PubMed

    Marzo, A; Ghirardi, P

    1977-05-01

    Biliary and urinary excretion of five tritium-labelled cardiac glycosides, i.e. Ouabain, K-strophanthoside, Digoxin, Digitoxin and Deslanatoside C, were investigated in anaesthetized guinea-pigs 5 h after i.v. or enteral administration. Urinary excretion is the main route of elimination in the case of Ouabain and Deslanatoside C. Conversely, biliary excretion is predominant in the case of Digoxin and Digitoxin. K-strophanthoside is excreted both via bile and urine. In conscious guinea-pigs treated i.v. with the same cardiac glycosides the highest levels were observed in urine, bile, kidneys and liver. The relative values of those levels were in agreement with the excretion pattern observed in anaesthetized animals. An inverse linear relation (P less than 0.05) was encountered between biliary excretion rate and polarity of glycoside molecula. This correlation has been previously observed by other authors in other species, but not in the rabbit. This suggests that the correlation may not be considered generally applicable at present.

  14. The effects of ambient pH on nitrogen excretion in early life stages of the American toad (Bufo americanus).

    PubMed

    Tattersall, G J; Wright, P A

    1996-04-01

    Acidification of breeding ponds has been identified as a potential threat to the survival and health of North American amphibian populations. The effects of acid exposure on ion and acid-balance are well known, but there is little information on how environmental water pH influences nitrogen balance in amphibians. The aim of this study was to determine the effects of moderately acidic water (pH 6.0) on nitrogen excretion in early life stages of the toad, Bufo americanus. Acid exposure (pH 6.0, 54 h) resulted in a 20-80% increase in ammonia-N excretion rates in embryos and early, middle and late tadpoles stages, whereas there was no significant effect on urea-N excretion. Tissue ammonia concentrations were significantly higher (+33%) in the embryos and 35-65% lower in the three groups of tadpoles exposed to water of pH 6.0 compared to control animals (pH 8.5). In embryos, ammonia excretion accounted for greater than 90% of total nitrogen excretion (ammonia-N + urea-N), but by the late tadpole stage this value had decreased to approximately 65%. These findings indicate that exposure of embryonic and larval B. americanus to moderately acidic water disrupts nitrogen balance by increasing nitrogen loss as ammonia, with no compensatory decrease in urea excretion.

  15. Biliary manganese excretion in conscious rats is affected by acute and chronic manganese intake but not by dietary fat.

    PubMed

    Malecki, E A; Radzanowski, G M; Radzanowski, T J; Gallaher, D D; Greger, J L

    1996-02-01

    We hypothesized that biliary excretion of manganese would be sensitive to acute and chronic variations in manganese and fat intakes. In the acute study, we gavaged rats with solutions containing 54Mn with either 0, 0.2, 1 or 10 mg Mn as MnCl2. We collected bile from unanesthesized rats that were simultaneously reinfused with bile acids. Total manganese excretion (from 0.5 to 6.5 h after dosing) was proportional to the acute doses (approximately 3.4% of doses). In the chronic study, weanling rats were fed diets containing 5 or 20 g corn oil/g diet and 0.49 or 72 micrograms Mn/g diet for 8 wk and then deprived of food for 12 h before bile collection. Manganese-deficient animals excreted only 0.7% as much manganese in bile as manganese-replete animals, but this reduction was not sufficient to prevent 50-80% reduction of tissue manganese concentrations. Moreover, biliary manganese excretion (calculated for 24 h) by both manganese-deficient and manganese-replete rats (deprived of food for previous 12 h) accounted for only 1% of their manganese intake on the previous day. Dietary fat and manganese concentrations had few effects on excretion of total or individual bile acids. Ours is the first report of biliary excretion of orally administered manganese by conscious rats. PMID:8632223

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

    NASA Astrophysics Data System (ADS)

    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

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

    NASA Astrophysics Data System (ADS)

    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.

  18. Arsenic drinking water exposure and urinary excretion among adults in the Yaqui Valley, Sonora, Mexico.

    PubMed

    Meza, Maria Mercedes; Kopplin, Michael J; Burgess, Jefferey L; Gandolfi, A Jay

    2004-10-01

    The objective of this study was to determine arsenic exposure via drinking water and to characterize urinary arsenic excretion among adults in the Yaqui Valley, Sonora, Mexico. A cross-sectional study was conducted from July 2001 to May 2002. Study subjects were from the Yaqui Valley, Sonora, Mexico, residents of four towns with different arsenic concentrations in their drinking water. Arsenic exposure was estimated through water intake over 24 h. Arsenic excretion was assessed in the first morning void urine. Total arsenic concentrations and their species arsenate (As V), arsenite (As III), monomethyl arsenic (MMA), and dimethyl arsenic (DMA) were determined by HPLC/ICP-MS. The town of Esperanza with the highest arsenic concentration in water had the highest daily mean intake of arsenic through drinking water, the mean value was 65.5 microg/day. Positive correlation between total arsenic intake by drinking water/day and the total arsenic concentration in urine (r = 0.50, P < 0.001) was found. Arsenic excreted in urine ranged from 18.9 to 93.8 microg/L. The people from Esperanza had the highest geometric mean value of arsenic in urine, 65.1 microg/L, and it was statistically significantly different from those of the other towns (P < 0.005). DMA was the major arsenic species in urine (47.7-67.1%), followed by inorganic arsenic (16.4-25.4%), and MMA (7.5-15%). In comparison with other reports the DMA and MMA distribution was low, 47.7-55.6% and 7.5-9.7%, respectively, in the urine from the Yaqui Valley population (except the town of Cocorit). The difference in the proportion of urinary arsenic metabolites in those towns may be due to genetic polymorphisms in the As methylating enzymes of these populations.

  19. Urine synaptopodin excretion is an important marker of glomerular disease progression

    PubMed Central

    Kwon, Soon Kil; Kim, Seung Jung; Kim, Hye-Young

    2016-01-01

    Background/Aims: Podocytes play an important role in maintaining the glomerular filtration barrier and in formation of the slit diaphragm. Podocyte loss is associated with chronic kidney disease progression, but it is not clear whether urinary podocyte proteins in urine reflect the clinical extent of glomerular damage. We investigated the correlation between the amounts of urinary podocyte proteins and renal function and albuminuria. Methods: The study enrolled 33 patients with diabetic kidney disease or glomerular disease and measured urinary podocytes proteins using Western blotting. Urinary podocyte proteins were measured according to the density of the bands on Western blotting. We measured serum creatinine and the spot urine albumin/creatinine ratio as markers of renal damage, and compared the correlation of urinary podocyte protein in the glomerular disease patients. Results: The mean patient age was 49.3 ± 16.5 years, the mean serum creatinine level was 2.30 ± 1.76 mg/dL, and the mean albumin/creatinine ratio was 4.85 ± 3.52. Among the podocyte proteins, urine synaptopodin showed strong correlation with serum creatinine by multivariate regression analysis (p < 0.001) and showed linear correlation (r = 0.429, p < 0.01). Urine podocyte proteins were increased in patients with diabetes, and synaptopodin showed the greatest significant difference (7.68 ± 5.61 vs. 2.56 ± 3.11, p < 0.001), but this might be associated with renal impairment. The urine albumin excretion did not differ between the diabetics and non-diabetics (p = 0.73). Conclusions: Urine synaptopodin is associated with serum creatinine elevation in the patients with glomerulonephritis including diabetic kidney disease regardless of urine albumin excretion. We suggest that the urine synaptopodin level can predict glomerular damage independently of the urine albumin excretion. PMID:27604800

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

    SciTech Connect

    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.

  1. Ammonia excretion in the Atlantic hagfish (Myxine glutinosa) and responses of an Rhc glycoprotein.

    PubMed

    Edwards, Susan L; Arnold, Justin; Blair, Salvatore D; Pray, Margaret; Bradley, Rachel; Erikson, Olivia; Walsh, Patrick J

    2015-05-01

    Hagfishes, the most ancient of the extant craniates, demonstrate a high tolerance for a number of unfavorable environmental conditions, including elevated ammonia. Proposed mechanisms of ammonia excretion in aquatic organisms include vesicular NH(4)(+) transport and release by exocytosis in marine crabs, and passive NH(3) diffusion, active NH(4)(+) transport, and paracellular leakage of NH3 or NH(4)(+) across the gills of fishes. Recently, an emerging paradigm suggests that Rhesus glycoproteins play a vital role in ammonia transport in both aquatic invertebrates and vertebrates. This study has identified an Rh glycoprotein ortholog from the gills of Atlantic hagfish. The hagfish Rhcg shares a 56-60% amino acid identity to other vertebrate Rhcg cDNAs. Sequence information was used to produce an anti-hagfish Rhcg (hRhcg) antibody. We have used hRhcg to localize protein expression to epithelial cells of the gill and the skin. In addition, we have quantified hRhcg expression following exposure to elevated plasma ammonia levels. Animals exposed to a 3 mmol/kg NH(4)Cl load resulted in significantly elevated plasma ammonia concentrations compared with controls for up to 4 h postinjection. This correlated with net ammonia excretion rates that were also significantly elevated for up to 4 h postinjection. Rhcg mRNA expression in both the gill and skin was significantly elevated by 15 min and 1 h, respectively, and hRhcg protein expression in gills was significantly elevated at 2, 4, and 8 h postinjection. These results demonstrate a potential role for Rhcg in the excretion of ammonia in the Atlantic hagfish.

  2. SN2-Palmitate Reduces Fatty Acid Excretion in Chinese Formula-fed Infants

    PubMed Central

    Bar-Yoseph, Fabiana; Lifshitz, Yael; Cohen, Tzafra; Malard, Patrice; Xu, Chungdi

    2016-01-01

    ABSTRACT Objectives: Palmitic acid (PA) comprises 17% to 25% of human milk fatty acids, of which 70% to 75% are esterified to the SN2 position of the triglyceride (SN2-palmitate). In vegetable oils, which are commonly used in infant formulas, palmitate is primarily esterified to other positions, resulting in reduced calcium and fat absorption and hard stools. The aim of this study was to elucidate the effects of SN2-palmitate on nutrient excretion. Methods: In total, 171 Chinese infants were included (within 14 days of birth) in this multicenter study. Formula-fed infants were randomly assigned to receive either SN2-palmitate formula (INFAT, n = 57) or control formula (n = 57). The formulas (Biostime, China) differed only in their SN2 PA proportions. Stool was collected at 6 postnatal weeks. Results: The stool dry weight and fat content of the SN2-palmitate group were lower compared with the control group (dry weight 4.25 g vs 7.28 g, P < 0.05; fat 0.8 g vs 1.2 g, P < 0.05). The lipid component was also significantly lower for the SN2-palmitate group (0.79 g vs 1.19 g, P < 0.05). PA, representing ∼50% of the saponified fatty acids, was significantly lower in the SN2-palmitate group compared with the control group (0.3 g vs 0.7 g, P < 0.01). Breast-fed infants had a significantly lower stool dry weight, fat content, and saponified fat excretion compared with formula-fed infants (P < 0.01). Conclusions: Similar to breast milk, the SN2-palmitate infant formula primarily reduced calcium-saponified fat excretion. The results of this study further emphasize the nutritional importance of SN2-palmitate structured fat for infants. PMID:26334255

  3. Effects of sodium N-methyl-N-dithiocarboxyglucamine on cadmium distribution and excretion

    SciTech Connect

    Gale, G.R.; Shinobu, L.A.; Jones, M.M.; Atkins, L.M.; Smith, A.B.

    1984-12-17

    Sodium N-methyl-N-dithiocarboxyglucamine (MDCG) was evaluated for its efficacy in mobilizing and promoting excretion of metallothionein-bound /sup 109/Cd using mice which had received 0.03 mg of CdCl/sub 2/.2.5H/sub 2/O along with 1.0 ..mu..Ci of /sup 109/CdCl/sub 2/ three weeks earlier. The MDCG-induced change in the fecal excretion of Cd ranged from a 15-fold increase over the control rate at the lowest dose level used (2.2 mmol/kg; 684 mg/kg) up to a 72-fold increase at the highest dose (8.8 mmol/kg; 2736 mg/kg) following three daily injections. The latter treatment administered Cd over a 3-day period of observation. Urinary Cd excretion was insignificant in both the control and treated groups. The whole body burden of Cd was reduced by over 50% following seven thrice-weekly i.p. injections of MDCG at 8.8 mmol/kg. There was a 60-65% reduction in both the liver and kidney Cd levels following the same treatment regimen. Radioassay of ten other organs and tissues revealed only modest changes. Testicular Cd was decreased slightly at the highest dose level, and heart tissue from each treated group contained slightly more Cd than controls. Results indicated a rather marked specificity of MDCG in lowering the Cd content of two organs most susceptible to Cd-induced toxicity.

  4. The effect of ACTH upon faecal glucocorticoid excretion in the koala.

    PubMed

    Davies, Nicole; Gillett, Amber; McAlpine, Clive; Seabrook, Leonie; Baxter, Greg; Lunney, Daniel; Bradley, Adrian

    2013-10-01

    Environmental changes result in physiological responses of organisms, which can adversely affect population dynamics and reduce resistance to disease. These changes are expressed in chronic levels of stress. The measurement of glucocorticoid (GC) concentrations in faeces is a non-invasive method for monitoring stress in wildlife. The metabolism and excretion of steroids differ significantly between species and, as a consequence, non-invasive methods must be physiologically validated for each species. Koalas (Phascolarctos cinereus) are declining in numbers through much of their range. The role of chronic stress in koala populations has not been identified. Prior to the assessment of faecal GC concentrations in wild koala populations, the excretion timing and concentrations of GCs need to be determined. In this study, we assessed a method for identifying and measuring the concentrations of GC metabolites in faecal pellets of captive koalas following ACTH treatment. The results show that an elevation of plasma cortisol concentrations, using sustained release of ACTH, results in elevated concentrations of faecal cortisol/cortisol metabolites. Taking into account the excretion time lag, an increase in faecal cortisol metabolite concentrations corresponds to the release of GCs from the adrenal cortex as early as 36 h before faecal pellet collection. The calculations of steroid partitioning of plasma cortisol showed that the ACTH-stimulated values were significantly different from the control values for the concentrations of free, corticosteroid-binding globulin-bound and albumin-bound cortisol. This study validates the use of faecal cortisol analysis to assess the activity of the hypothalamo-pituitary-adrenocortical axis in freshly collected koala faecal pellets and indicates that the method should be suitable to assess the adrenocortical status of koalas in wild populations.

  5. Urinary Sodium and Potassium Excretion and Carotid Atherosclerosis in Chinese Men and Women

    PubMed Central

    Dai, Xiao-Wei; Wang, Cheng; Xu, Ying; Guan, Ke; Su, Yi-Xiang; Chen, Yu-Ming

    2016-01-01

    Limited studies have examined the association between sodium (Na) and potassium (K) levels and the risk of atherosclerosis. This study examined whether higher Na and Na/K levels and low K levels were independent risk factors for atherosclerosis. This community-based cross-sectional study included 3290 subjects (1067 men and 2223 women) 40 to 75 years of age in Guangzhou, China, between 2011 and 2013. Urinary excretion of Na and K were measured from the first morning void, and creatinine-adjusted values were used. The intima-media thickness (IMT) of the carotid common artery and the carotid bifurcation was measured with high-resolution B-mode ultrasonography. Dietary K and Na intake and other covariates were obtained by face-to-face interviews. A significant positive association was seen between urinary Na excretion and carotid atherosclerosis after adjustment for age, sex, and other lifestyle covariates. The odds ratios (OR) and 95% confidence interval (CI) of the highest (vs. lowest) quartile of urinary Na were 1.32 (1.04–1.66) for carotid plaques, 1.48 (1.18–1.87) for increased common carotid artery IMT, and 1.55 (1.23–1.96) for increased carotid bifurcation IMT (all p-trend < 0.01). A similar positive association was observed between urinary Na/K levels and carotid plaque and increased IMT, and between dietary Na intake and increased bifurcation IMT. Regarding potassium data, we only found a significantly lower presence of carotid plaque (OR 0.72, 95% CI 0.57–0.91) for quartile 2 (vs. 1) of urinary K. Our findings suggest that higher levels of urinary excretion Na and Na/K are significantly associated with greater presence of carotid atherosclerosis in Chinese adults. PMID:27706075

  6. Time course of chronic oral cadmium nephrotoxicity in Wistar rats: excretion of urinary enzymes.

    PubMed

    Bomhard, E M; Maruhn, D; Rinke, M

    1999-11-01

    Twelve male and female Wistar rats each received cadmium (as CdCl2) in their diet at concentrations of 0, 10, 50, and 250 ppm for 72 weeks. After 1, 4, 8, 13, 18, 26, 32, 45, 57, and 68 weeks a total of 8 enzymes from different cellular compartments of the nephron were measured. At the end of the study period, the kidneys were examined histopathologically. Concentrations up to and including 50 ppm did not induce any adverse effect. At 250 ppm, growth of male and female animals was markedly retarded. Significantly increased activities of the cytosolic phosphohexose isomerase were excreted by males and females receiving 250 ppm at all timepoints from week 13. The values of the mitochondrial glutamate dehydrogenase were mostly elevated from week 1 to 57, however, due to a wide scatter range, were only occasionally significantly different from control values. The brush border enzymes (gamma-glutamyl transferase, alkaline phosphatase and leucine arylamidase) were not changed in a relevant manner in female rats, while in 250 ppm males the excreted activity of ALP and LAP from week 1 to week 18, and that of GGT during the entire study period were significantly lower than the control values. Excretion of the lysosomal enzymes aryl sulfatase A, beta-galactosidase, and beta-N-acetyl-D-glucosaminidase was at no time influenced in a noteworthy manner. Histopathology after 72 weeks revealed chronic but also acute degenerative changes in the kidneys of 250 ppm males and females. A comparison of published data on persons having undergone high cadmium exposure with the results presented here shows remarkable differences.

  7. Urinary isothiocyanate excretion, brassica consumption, and gene polymorphisms among women living in Shanghai, China.

    PubMed

    Fowke, Jay H; Shu, Xiao-Ou; Dai, Qi; Shintani, Ayumi; Conaway, C Clifford; Chung, Fung-Lung; Cai, Qiuyin; Gao, Yu-Tang; Zheng, Wei

    2003-12-01

    Alternative measures of Brassica vegetable consumption (e.g., cabbage) may clarify the association between Brassica and cancer risk. Brassica isothiocyanates (ITCs) are excreted in urine and may provide a sensitive and food-specific dietary biomarker. However, the persistence of ITCs in the body may be brief and dependent on the activity of several Phase II enzymes, raising questions about the relationship between a single ITC measure and habitual dietary patterns. This study investigates the association between urinary ITC excretion and habitual Brassica consumption, estimated by a food frequency questionnaire, among healthy Chinese women enrolled in the Shanghai Breast Cancer Study. Participants (n = 347) completed a validated food frequency questionnaire querying habitual dietary intake during the prior 5 years and provided a fasting first-morning urine specimen. Genetic deletion of glutathione S-transferases (GSTM1/GSTT1), and single nucleotide substitutions in GSTP1 (A313G) and NAD(P)H:quinone oxidoreductase 1 (NQO1: C609T), were identified from blood DNA. Urinary ITC excretion levels were marginally higher with the GSTT1-null or GSTP1-G/G genotypes (P = 0.07, P = 0.05, respectively). Mean habitual Brassica intake was 98.3 g/day, primarily as bok choy, and Brassica intake significantly increased across quartile categories of ITC levels. The association between habitual Brassica intake and urinary ITC levels was stronger among women with GSTT1-null or GSTP1-A/A genotypes, or NQO1 T-allele, and the interaction was statistically significant across GSTP1 genotype. In conclusion, a single urinary ITC measure, in conjunction with markers of Phase II enzyme activity, provides a complementary measure of habitual Brassica intake among Shanghai women.

  8. The relationship of milk urea nitrogen to urine nitrogen excretion in Holstein and Jersey cows.

    PubMed

    Kauffman, A J; St-Pierre, N R

    2001-10-01

    The objectives of this study were to assess the relationship between urinary nitrogen excretion (UN, g/d) and milk urea nitrogen concentration (MUN, mg/dl) and whether the types of carbohydrates fed interacts with the dietary CP and the breed (size) of cows to affect this relationship. Eight multiparous cows (four Holstein and four Jersey) were fed four different diets in a 2 x 2 factorial arrangement of levels of crude protein (13 and 17%) and levels of neutral detergent fiber (30 and 40%). The experimental design was a split plot Latin square with breeds forming the main plots and diets forming the subplots. Experimental periods were 3 wk in length, with d 1 to 14 used for adjustment and d 15 to 19 used for a total collection of urine and feces. Crude protein concentrations had a significant effect on milk, milk fat and protein production, plasma urea N, MUN, and on N balance measurements (N intake, fecal and urinary N excretion, milk N production, N retention, apparent N digestibility, and N efficiency). Neutral detergent fiber levels had no effect on any production parameters or N balance measurements. The relationship between urinary N and MUN was linear over the range of MUN values observed and different for the two breeds. The breed effect on the UN-MUN relationship was no longer significant (P = 0.63) when body weight (BW) was included in the model. The optimal allometric coefficient for BW was 0.96 and was not different from 1.0. Therefore, the following equation is proposed to predict UN excretion based on MUN and BW: UN (g/d) = 0.0259 (+/- 0.0006) BW (kg) x MUN (mg/dl).

  9. Manipulation of dietary methionine+cysteine and threonine in broilers significantly decreases environmental nitrogen excretion.

    PubMed

    Donato, D C Z; Sakomura, N K; Silva, E P; Troni, A R; Vargas, L; Guagnoni, M A N; Meda, B

    2016-06-01

    The intensification of livestock have increased the emission of pollutants to the environment, leading to a growing interest in seeking strategies that minimise these emissions. Studies have shown that it is possible to manipulate diets by reducing CP levels and thus reducing nitrogen (N) excretion, without compromising performance. However, there is no knowledge of any study that has focused on reducing N excretion and relating this reduction to individual amino acids. This study investigated the effect of dietary methionine+cysteine (MC) and threonine (THR), the two most limiting amino acids for broiler production, on nitrogen excretion (NE) and nitrogen deposition (ND) and determined the efficiency of utilisation of both amino acids for protein deposition. Six trials were conducted to measure the NE and ND in broiler chickens during three rearing phases in response to dietary amino acid. The efficiency of utilisation of the amino acids was calculated by linear regression of body protein deposition and the amino acid intake. Despite the differences between sexes and phases, the efficiency of utilisation was the same, being 0.60 and 0.59 for MC and THR, respectively. The rate of NE behaved exponentially, increasing with amino acid intake, and can exceed 50% of N intake, being higher than ND. On average, for a reduction in intake of each unit of MC or THR (mg) there is a reduction of 0.5% of NE. Although this reduction seems low, considering that it corresponds to changes in one amino acid only, the impact on a large scale would be significant. Knowledge of how animals respond to NE and ND/protein deposition according to amino acid dietary content may represent new efforts towards reducing the impact on environment. PMID:27076031

  10. Nocturnal 6-hydroxymelatonin sulfate excretion in female workers exposed to magnetic fields

    SciTech Connect

    Juutilainen, J; Stevens, Richard G. ); Anderson, Larry E. ); Hansen, Norman H.; Kilpelainen, M; Kumlin, T; Laitinen, J T.; Sobell, Eugene; Wilson, Bary W. )

    2000-03-15

    The objective of this study was to determine whether daytime occupational exposure to extremely low frequency magnetic fields (MFs) suppresses nocturnal melatonin production. Sixty female volunteers were recruited. Thirty-nine worked in a garment factory, and 21 office workers served as a reference group. Exposure assessment was based on the type of sewing machine used and MF measurements around each type of machine. Eye-level MF flux density was used to classify the operators to higher (> 1 microT) and lower (0.3-1 microT) exposure categories. A third group of factory workers had diverse MF exposures from other sources. The reference group had average exposure of about 0.15 microT. Urine samples were collected on Friday and Monday for three consecutive weeks. Melatonin production was assessed as urinary 6-hydroxymelatonin sulfate (6-OHMS) excretion. The ratio of Friday morning/Monday morning 6-OHMS was used to test the hypothesis that melatonin production is suppressed after 4 days of occupational MF exposure with significant recovery during the weekend. Possible chronic suppression of melatonin production was evaluated by studying exposure-related differences in the Friday values by multivariate regression analysis. The Monday/Friday ratios were close to 1.0, suggesting that there is no increase in melatonin production over the weekend. The average 6-OHMS excretion on Friday was lower among the factory workers than in the reference group, but no monotonous dose-response was observed. Multivariate regression analysis identified MF exposure, smoking, and age as significant explanatory variables associated with decreased 6-OHMS excretion.

  11. Increased urinary excretion of 8-hydroxydeoxyguanosine in engine room personnel exposed to polycyclic aromatic hydrocarbons

    PubMed Central

    Nilsson, R; Nordlinder, R; Moen, B; Ovrebo, S; Bleie, K; Skorve, A; Hollund, B; Tagesson, C

    2004-01-01

    Background: Previous investigations indicate that engine room personnel on ships are exposed to polycyclic aromatic hydrocarbons (PAH) from oil and oil products, with dermal uptake as the major route of exposure. Several PAH are known carcinogens and mutagens. Aims: To investigate the urinary excretion of a marker for oxidative DNA damage, 8-hydroxydeoxy-guanosine (8OHdG), in engine room personnel, and to study the association between 8OHdG and 1-hydroxypyrene (1OHP), a biological marker for PAH exposure. Methods: Urine samples were collected from engine room personnel (n = 36) on 10 Swedish and Norwegian ships and from unexposed controls (n = 34) with similar age and smoking habits. The exposure to oils, engine exhaust, and tobacco smoke 24 hours prior to sampling was estimated from questionnaires. The urinary samples were frozen for later analyses of 8OHdG and 1OHP by high performance liquid chromatography. Results: Excretion in urine of 8OHdG (adjusted to density 1.022) was similar for controls (mean 18.0 nmol/l, n = 33), and for those who had been in the engine room without skin contact with oils (mean 18.7 nmol/l, n = 15). Engine room personnel who reported skin contact with oil had increased excretion of 8OHdG (mean 23.2 nmol/l, n = 19). The difference between this group and the unexposed controls was significant. The urinary levels of ln 1OHP and ln 8OHdG were significantly correlated, and the association was still highly significant when the effects of smoking and age were accounted for in a multiple regression analysis. Conclusion: Results indicate that exposure to PAH or possibly other compounds from skin contact with oils in engine rooms may cause oxidative DNA damage. PMID:15258276

  12. Urinary isothiocyanate excretion, brassica consumption, and gene polymorphisms among women living in Shanghai, China.

    PubMed

    Fowke, Jay H; Shu, Xiao-Ou; Dai, Qi; Shintani, Ayumi; Conaway, C Clifford; Chung, Fung-Lung; Cai, Qiuyin; Gao, Yu-Tang; Zheng, Wei

    2003-12-01

    Alternative measures of Brassica vegetable consumption (e.g., cabbage) may clarify the association between Brassica and cancer risk. Brassica isothiocyanates (ITCs) are excreted in urine and may provide a sensitive and food-specific dietary biomarker. However, the persistence of ITCs in the body may be brief and dependent on the activity of several Phase II enzymes, raising questions about the relationship between a single ITC measure and habitual dietary patterns. This study investigates the association between urinary ITC excretion and habitual Brassica consumption, estimated by a food frequency questionnaire, among healthy Chinese women enrolled in the Shanghai Breast Cancer Study. Participants (n = 347) completed a validated food frequency questionnaire querying habitual dietary intake during the prior 5 years and provided a fasting first-morning urine specimen. Genetic deletion of glutathione S-transferases (GSTM1/GSTT1), and single nucleotide substitutions in GSTP1 (A313G) and NAD(P)H:quinone oxidoreductase 1 (NQO1: C609T), were identified from blood DNA. Urinary ITC excretion levels were marginally higher with the GSTT1-null or GSTP1-G/G genotypes (P = 0.07, P = 0.05, respectively). Mean habitual Brassica intake was 98.3 g/day, primarily as bok choy, and Brassica intake significantly increased across quartile categories of ITC levels. The association between habitual Brassica intake and urinary ITC levels was stronger among women with GSTT1-null or GSTP1-A/A genotypes, or NQO1 T-allele, and the interaction was statistically significant across GSTP1 genotype. In conclusion, a single urinary ITC measure, in conjunction with markers of Phase II enzyme activity, provides a complementary measure of habitual Brassica intake among Shanghai women. PMID:14693750

  13. Human studies on the absorption, distribution, metabolism, and excretion of tea polyphenols.

    PubMed

    Clifford, Michael N; van der Hooft, Justin J J; Crozier, Alan

    2013-12-01

    Recent research on the bioavailability of flavan-3-ols after ingestion of green tea by humans is reviewed. Glucuronide, sulfate, and methyl metabolites of (epi)catechin and (epi)gallocatechin glucuronide reach peak nanomolar per liter plasma concentrations 1.6-2.3 h after intake, indicating absorption in the small intestine. The concentrations then decline, and only trace amounts remain 8 h after ingestion. Urinary excretion of metabolites over a 24-h period after green tea consumption corresponded to 28.5% of the ingested (epi)catechin and 11.4% of (epi)gallocatechin, suggesting higher absorption than that of most other flavonoids. The fate of (-)-epicatechin-3-O-gallate, the main flavan-3-ol in green tea, is unclear because it appears unmetabolized in low concentrations in plasma but is not excreted in urine. Possible enterohepatic recirculation of flavan-3-ols is discussed along with the impact of dose and other food components on flavan-3-ol bioavailability. Approximately two-thirds of the ingested flavan-3-ols pass from the small to the large intestine where the action of the microbiota results in their conversion to C-6-C-5 phenylvalerolactones and phenylvaleric acids, which undergo side-chain shortening to produce C-6-C-1 phenolic and aromatic acids that enter the bloodstream and are excreted in urine in amounts equivalent to 36% of flavan-3-ol intake. Some of these colon-derived catabolites may have a role in vivo in the potential protective effects of tea consumption. Although black tea, which contains theaflavins and thearubigins, is widely consumed in the Western world, there is surprisingly little research on the absorption and metabolism of these compounds after ingestion and their potential impact on health.

  14. Modelling phosphorus intake, digestion, retention and excretion in growing and finishing pig: model evaluation.

    PubMed

    Symeou, V; Leinonen, I; Kyriazakis, I

    2014-10-01

    A deterministic, dynamic model was developed, to enable predictions of phosphorus (P) digested, retained and excreted for different pig genotypes and under different dietary conditions. Before confidence can be placed on the predictions of the model, its evaluation was required. A sensitivity analysis of model predictions to ±20% changes in the model parameters was undertaken using a basal UK industry standard diet and a pig genotype characterized by British Society Animal Science as being of 'intermediate growth'. Model outputs were most sensitive to the values of the efficiency of digestible P utilization for growth and the non-phytate P absorption coefficient from the small intestine into the bloodstream; all other model parameters influenced model outputs by <10%, with the majority of the parameters influencing outputs by <5%. Independent data sets of published experiments were used to evaluate model performance based on graphical comparisons and statistical analysis. The literature studies were selected on the basis of the following criteria: they were within the BW range of 20 to 120 kg, pigs grew in a thermo-neutral environment; and they provided information on P intake, retention and excretion. In general, the model predicted satisfactorily the quantitative pig responses, in terms of P digested, retained and excreted, to variation in dietary inorganic P supply, Ca and phytase supplementation. The model performed well with 'conventional', European feed ingredients and poorly with 'less conventional' ones, such as dried distillers grains with solubles and canola meal. Explanations for these inconsistencies in the predictions are offered in the paper and they are expected to lead to further model development and improvement. The latter would include the characterization of the origin of phytate in pig diets.

  15. Metabolism and excretion studies of oral administered naringin, a putative antitussive, in rats and dogs.

    PubMed

    Liu, Menghua; Zou, Wei; Yang, Cuiping; Peng, Wei; Su, Weiwei

    2012-04-01

    Naringin, a major active flavonone glycoside from a traditional Chinese medicine Huajuhong, has been demonstrated to have activities such as peripheral antitussive, mucoregulator and anti-inflammatory. The purpose of this study was to elucidate the metabolism and mass balance of orally administered naringin in rats and dogs. After oral administration of naringin to rats and dogs at doses of 42 mg/kg and 12.4 mg/kg, respectively, metabolites in excreta were identified using a LC-Q-TOF system. The major metabolites including naringin, total naringenin (including free naringenin and its conjugates) and 4-hydroxyphenylpropionic acid in excreta were quantified by a LC-MS/MS system. Twenty-two metabolites were identified in dogs and 17 metabolites were detected in rats. The observed routes of naringin metabolism were hydroxylation, methylation, acetylation, hydrogenation, deglycosylation, dehydrogenation, glucuronidation, sulfation, glucosylation, ring-fission, oxidation, glycine conjugation and dehydroxylation. On the basis of these identified metabolites, a comprehensive metabolic pathway of naringin was proposed. About 21% of administered naringin was recovered in rat excreta in the form of naringin, total naringenin and 4-hydroxyphenylpropionic acid, and about 60% was recovered in dog excreta. The levels of 4-hydroxyphenylpropionic acid in excreta were higher than those of naringin and total naringenin, and the quantified metabolites were excreted more through feces, rather than urine. Most of these metabolites were excreted within 36 h post dose. The results of metabolism and excretion studies provide an explanation for future pharmacological and toxicological findings and are the groundwork for clinical studies.

  16. Papaverine inhibits transcytotic vesicle transport and lipid excretion into bile in isolated perfused rat liver.

    PubMed

    Hayakawa, T; Katagiri, K; Hoshino, M; Nakai, T; Ohiwa, T; Kumai, T; Miyaji, M; Takeuchi, T; Corasanti, J; Boyer, J L

    1992-10-01

    Papaverine is a nonspecific smooth muscle relaxant and a phosphodiesterase inhibitor. Its effects on biliary excretion of lipids and horseradish peroxidase were investigated in a single-pass isolated perfused rat liver model. A constant infusion of papaverine (1.6 mumol/min; 40 mumol/L) significantly increased bile flow (microliters per minute per gram of liver) before (2.03 +/- 0.09 vs. 1.0 +/- 0.06) and after sodium taurocholate infusion (2.77 +/- 0.10 vs. 1.88 +/- 0.11). However, papaverine significantly and reversibly reduced biliary excretion of phospholipids and cholesterol (nanomoles per minute per gram of liver) after a 1.0 mumol/min sodium taurocholate infusion, from 7.45 +/- 0.83 and 1.42 +/- 0.15 to 1.75 +/- 0.18 and 0.39 +/- 0.06, respectively (p less than 0.01), whereas secretion of bile acids was unaffected. When a 1-min pulse of horseradish peroxidase (25 mg) was infused in isolated perfused rat liver after a continuous infusion of N6,O-2'-dibutyryladenosine 3',5'-cyclic monophosphate (0.25 mumol/min; 6.25 mumol/L), horseradish peroxidase appeared in bile in an early (4 to 6 min) and late (20 to 25 min) peak. Papaverine significantly reduced the late peak, from 1.211 +/- 0.264 to 0.498 +/- 0.107 (p less than 0.01). Papaverine had no significant effects on either cyclic AMP or cyclic GMP in the liver and bile, although it has been reported that papaverine is a phosphodiesterase inhibitor. These findings indicate that papaverine inhibits biliary excretion of lipids but not bile acids, and they suggest that papaverine has an inhibitory effect on transcytotic vesicle transport independent of an increase of cyclic nucleotides in hepatocytes.

  17. Excretion of hexachlorobenzene and metabolites in feces in a highly exposed human population.

    PubMed Central

    To-Figueras, J; Barrot, C; Sala, M; Otero, R; Silva, M; Ozalla, M D; Herrero, C; Corbella, J; Grimalt, J; Sunyer, J

    2000-01-01

    A set of 53 individuals from a population highly exposed to airborne hexachlorobenzene (HCB) were selected to study the elimination kinetics of this chemical in humans. The volunteers provided blood, 24-hr urine, and feces samples for analysis of HCB and metabolites. The serum HCB concentrations ranged from 2.4 to 1,485 ng/mL (mean +/- SD, 124 +/- 278), confirming that this human population has the highest HCB blood levels ever reported. All analyzed feces samples contained unchanged HCB (range, 11-3,025 ng/g dry weight; mean +/- SD, 395 +/- 629). The HCB concentration in feces strongly correlated with HCB in serum (r = 0.85; p < 0.001), suggesting an equilibrium in feces/serum that is compatible with a main pulmonary entrance of the chemical and low intestinal excretion of nonabsorbed foodborne HCB. The equilibrium is also compatible with a nonbiliary passive transfer of the chemical to the intestinal lumen. Two HCB main metabolites, pentachlorophenol (PCP) and pentachlorobenzenethiol (PCBT), were detected in 51% and 54% of feces samples, respectively. All urine samples contained PCP and PCBT, confirming the conclusions of a previous study [Environ Health Perspect 105:78-83 (1997)]. The comparison between feces and urine showed that whereas daily urinary elimination of metabolites may account for 3% of total HCB in blood, intestinal excretion of unchanged HCB may account for about 6%, thus showing the importance of metabolism in the overall elimination of HCB. The elimination of HCB and metabolites by both routes, however, appears to be very small (< 0.05%/day) as compared to the estimated HCB adipose depots. Features of HCB kinetics that we present in this study, i.e., nonsaturated intestinal elimination of HCB and excretion in feces and urine of inert glutathione derivatives, may explain, in part, the absence of porphyria cutanea in this human population heavily exposed to HCB. Images Figure 1 Figure 2 PMID:10903610

  18. Metabolism and excretion of anacetrapib, a novel inhibitor of the cholesteryl ester transfer protein, in humans.

    PubMed

    Kumar, Sanjeev; Tan, Eugene Y; Hartmann, Georgy; Biddle, Zachary; Bergman, Arthur J; Dru, James; Ho, Jonathan Z; Jones, Allen N; Staskiewicz, Steve J; Braun, Matthew P; Karanam, Bindhu; Dean, Dennis C; Gendrano, Isaias Noel; Graves, Mark W; Wagner, John A; Krishna, Rajesh

    2010-03-01

    Anacetrapib is a novel cholesteryl ester transfer protein inhibitor being developed for the treatment of primary hypercholesterolemia and mixed dyslipidemia. The absorption, distribution, metabolism, and excretion of anacetrapib were investigated in an open-label study in which six healthy male subjects received a single oral dose of 150 mg and 165 microCi of [(14)C]anacetrapib. Plasma, urine, and fecal samples were collected at predetermined times for up to 14 days postdose and were analyzed for total radioactivity, the parent compound, and metabolites. The majority of the administered radioactivity (87%) was eliminated by fecal excretion, with negligible amounts present in urine (0.1%). The peak level of radioactivity in plasma (approximately 2 microM equivalents of [(14)C]anacetrapib) was achieved approximately 4 h postdose. The parent compound was the major radioactive component (79-94% of total radioactivity) in both plasma and feces. Three oxidative metabolites, M1, M2, and M3, were detected in plasma and feces and were identified as the O-demethylated species (M1) and two secondary hydroxylated derivatives of M1 (M2 and M3). Each metabolite was detected at low levels, representing excretion of metabolites by the biliary-fecal route.

  19. [Studies on distribution, excretion and subacute toxicity of squalane in dogs].

    PubMed

    Kamimura, H; Koga, N; Oguri, K; Yoshimura, H; Inoue, H; Sato, K; Ohkubo, M

    1989-05-01

    In the previous papers, we demonstrated, by using rats, that squalane (2,6,10,15,19,23-hexamethyltetracosane) could stimulate the fecal excretion of 2,3,4,7,8-pentachlorodibenzofuran, which was regarded as the most important etiologic agent of yusho among PCB and PCDF congeners found in the causal rice oil. We also reported that, in rats, squalane was not essentially absorbed from the gastrointestinal tract, and did not show any appreciable side effects during the 3-month treatment. In the present paper, we have investigated the distribution, excretion and subacute toxicity of squalane in beagle dogs. The fecal excretion of squalane accounted for about 83% of dose during the initial 2 days after administration at a single oral dose of 1,200 mg/kg to male dogs. On day 3, absorbed squalane was mostly distributed to the hair and the skin, and the concentrations in these tissues were decreased on day 6. These results suggested that most of squalane administered orally was not absorbed from the gastrointestinal tract, but a part was absorbed and excreted through the hair. In addition, squalane distributed into the liver was found to be eliminated rather slowly. A long-term (13-week) treatments with squalane orally at doses of 400 mg/kg/day or 1,200 mg/kg/day in male and female dogs, resulted also in accumulation of squalane in the liver at a level of about 3% (400 mg/kg) or about 6% (1,200 mg/kg) of the daily dose. This accumulation of squalane in the liver was highest among all the tissues. Nevertheless, no appreciable toxic signs were observed in the serum biochemical tests and the hepatic functional test for squalane groups. Therefore, squalane accumulating in the liver, did not seem to disturb the hepatic physiological functions. It was suggested also in a long-term treatment that the skin and the hair played the most important role in the elimination of squalane. In conclusion, the present studies on subacute toxicity tests suggested that squalane did not give any

  20. Urinary AASA excretion is elevated in patients with molybdenum cofactor deficiency and isolated sulphite oxidase deficiency.

    PubMed

    Mills, Philippa B; Footitt, Emma J; Ceyhan, Serkan; Waters, Paula J; Jakobs, Cornelis; Clayton, Peter T; Struys, Eduard A

    2012-11-01

    Analysis of α-aminoadipic semialdehyde is an important tool in the diagnosis of antiquitin deficiency (pyridoxine-dependent epilepsy). However continuing use of this test has revealed that elevated urinary excretion of α-aminoadipic semialdehyde is not only found in patients with pyridoxine-dependent epilepsy but is also seen in patients with molybdenum cofactor deficiency and isolated sulphite oxidase deficiency. This should be taken into account when interpreting the laboratory data. Sulphite was shown to inhibit α-aminoadipic semialdehyde dehydrogenase in vitro.

  1. Fluorescent method for the detection of excreted ribonuclease around bacterial colonies.

    PubMed

    Lanyi, J K; Lederberg, J

    1966-11-01

    Lanyi, Janos K. (Stanford University School of Medicine, Palo Alto, Calif.), and Joshua Lederberg. Fluorescent method for the detection of excreted ribonuclease around bacterial colonies. J. Bacteriol. 92:1469-1472. 1966.-A test for the release of extracellular ribonuclease by Bacillus subtilis colonles was developed. The method consists of incorporating acridine orange and ribonucleic acid into nutrient agar plates and viewing the grown bacterial colonies under ultraviolet light. Regions of ribonuclease secretion appear as dark halos around the colonies on a green fluorescent background. The theoretical basis and the utility of this test are discussed.

  2. Renal excretion in channel catfish following injection of quinaldine sulphate or 3-trifluoromethyl-4-nitrophenol

    USGS Publications Warehouse

    Allen, J.L.; Hunn, J.B.

    1977-01-01

    Channel catfish, Ictalurus punctatus Rafinesque, injected intraperitoneally with 2-methyl-quinoline sulphate (QdSO4) or 3-trifluoromethyl-4-nitrophenol (TFM) eliminate most of the dose of these compounds by extra-renal routes. Patterns of renal excretion of Na+, K+, Ca2+, Mg2+, and Cl- (pEq kg-1 h-1) appeared to be associated with the 'stress' of the urine collection technique rather than with the elimination of either compound. Concentrations of Na+, K+, Ca2+, Mg2+, and Cl- (mEq/1) were determined in urine, plasma and gall bladder bile.

  3. [LH excretion during the ovulatory cycle and during therapy with various estrogen-gestagen combinations].

    PubMed

    Göretzlehner, G; Wilken, H

    1972-11-01

    Immunochemical determination of urinary LH was carried out in 7 normally ovulating women and in 25 women treated with various combined, sequential, and depot hormonal contraceptives. In ovulatory cycles without hormone treatment an LH peak was always observed at midcycle. During treatment with Ovosiston, OZN, and Quinestrol-norethisterone acetate, no LH peak was seen. In women receiving sequential preparations (mestranol-chlormadinone acetate, estrone cyanate-chlormadinone acetate), elevated LH levels were observed during estrogen medication. LH excretion was suppressed after administration of chlormadinone acetate. LH levels were also slightly elevated before and after medication with Quinestrol-chlormadinone acatate (1 pill per month). PMID:4121480

  4. Prediction of metabolisable energy value of broiler diets and water excretion from dietary chemical analyses.

    PubMed

    Carré, B; Lessire, M; Juin, H

    2013-08-01

    Thirty various pelleted diets were given to broilers (8/diet) for in vivo measurements of dietary metabolisable energy (ME) value and digestibilities of proteins, lipids, starch and sugars from day 27 to day 31, with ad libitum feeding and total collection of excreta. Water excretion was also measured. Amino acid formulation of diets was done on the basis of ratios to crude proteins. Mean in vivo apparent ME values corrected to zero nitrogen retention (AMEn) were always lower than the AMEn values calculated for adult cockerels using predicting equations from literature based on the chemical analyses of diets. The difference between mean in vivo AMEn values and these calculated AMEn values increased linearly with increasing amount of wheat in diets (P = 0.0001). Mean digestibilities of proteins, lipids and starch were negatively related to wheat introduction (P = 0.0001). The correlations between mean in vivo AMEn values and diet analytical parameters were the highest with fibre-related parameters, such as water-insoluble cell-walls (WICW) (r = -0.91) or Real Applied Viscosity (RAV) (r = -0.77). Thirteen multiple regression equations relating mean in vivo AMEn values to dietary analytical data were calculated, with R² values ranging from 0.859 to 0.966 (P = 0.0001). The highest R² values were obtained when the RAV parameter was included in independent variables. The direct regression equations obtained with available components (proteins, lipids, starch, sucrose and oligosaccharides) and the indirect regression equations obtained with WICW and ash parameters showed similar R² values. Direct or indirect theoretical equations predicting AMEn values were established using the overall mean in vivo digestibility values. The principle of indirect equations was based on the assumption that WICW and ashes act as diluters. Addition of RAV or wheat content in variables improved the accuracy of theoretical equations. Efficiencies of theoretical equations for predicting AMEn

  5. The release, tissue distribution and excretion of mercury from experimental amalgam tattoos.

    PubMed Central

    Cox, S. W.; Eley, B. M.

    1986-01-01

    Following the subcutaneous implantation of powdered dental amalgam in guinea pigs, there was an initial extrusion of material from the healing implantation wounds. Longer-term release of mercury from the lesions was demonstrated by linear regression analysis of the mercury contents of implant sites removed after time periods of up to 2 years. Raised mercury levels were detected in the blood, bile, kidneys, liver, spleen and lungs of implanted animals; by far the highest concentrations were found in the renal cortex. Mercury was excreted with the urine and, to a lesser extent, the faeces. The pattern of mercury redistribution resembled that seen following chronic exposure to mercuric compounds. PMID:3801303

  6. The effect of zinc supplementation on the urinary excretion of elements in female athletes.

    PubMed

    Eskici, Gunay; Gunay, Mehmet; Baltaci, Abdulkerim Kasim; Mogulkoc, Rasim

    2016-01-01

    This study was carried out to find out how oral zinc supplementation to elite athletes affects the element changes in the urine. The study registered 10 female athletes who were on the women's volleyball team of Gazi University Sports Club and whose mean age, weight, and height were 14.2±0.42 years, 59.8±7.79kg and 173.6±6.15 cm. The study protocol was approved by the local ethics committee. The athletes who continued their daily routine training sessions (6 days/week) were supplemented with 220mg/day oral zinc sulfate for 4 weeks. In order to induce exhaustion, the subjects were put to a 20-meter shuttle run test before and after supplementation. A total, 7 times urine samples were collected follows as pre and post exercise before the start of the experiment and at the end (4 times), at the end of first, second and third week (3 times). Urinary levels of magnesium, phosphorus, and calcium (mg/dl), as well as zinc, copper, and selenium (μg/dl) were analyzed in the atomic emission device (ICP-MS). Arithmetic means and standard errors of the data were calculated. Kruskal Wallis test was used to determine differences between weeks. Values for which p<0,05 were considered significant. When compared to resting values, urinary excretion of copper and selenium decreased in exercise (p<0,05), but increased with zinc supplementation (p<0,05). Pre- and post-supplementation exercise resulted in reduced urinary zinc excretion (p<0,05). Zinc supplementation increased urinary zinc excretion in one-week intervals over the course of 4 weeks (p<0,05), and reduced selenium levels (p<0,05). When zinc is supplemented to athletes, the relation between the duration and dose of supplementation is important. The results of the study indicated that zinc does not have any negative effect on the urinary excretion of the concerned elements. It can thus be concluded that athletes may benefit from zinc support.

  7. The effect of zinc supplementation on the urinary excretion of elements in female athletes.

    PubMed

    Eskici, Gunay; Gunay, Mehmet; Baltaci, Abdulkerim Kasim; Mogulkoc, Rasim

    2016-01-01

    This study was carried out to find out how oral zinc supplementation to elite athletes affects the element changes in the urine. The study registered 10 female athletes who were on the women's volleyball team of Gazi University Sports Club and whose mean age, weight, and height were 14.2±0.42 years, 59.8±7.79kg and 173.6±6.15 cm. The study protocol was approved by the local ethics committee. The athletes who continued their daily routine training sessions (6 days/week) were supplemented with 220mg/day oral zinc sulfate for 4 weeks. In order to induce exhaustion, the subjects were put to a 20-meter shuttle run test before and after supplementation. A total, 7 times urine samples were collected follows as pre and post exercise before the start of the experiment and at the end (4 times), at the end of first, second and third week (3 times). Urinary levels of magnesium, phosphorus, and calcium (mg/dl), as well as zinc, copper, and selenium (μg/dl) were analyzed in the atomic emission device (ICP-MS). Arithmetic means and standard errors of the data were calculated. Kruskal Wallis test was used to determine differences between weeks. Values for which p<0,05 were considered significant. When compared to resting values, urinary excretion of copper and selenium decreased in exercise (p<0,05), but increased with zinc supplementation (p<0,05). Pre- and post-supplementation exercise resulted in reduced urinary zinc excretion (p<0,05). Zinc supplementation increased urinary zinc excretion in one-week intervals over the course of 4 weeks (p<0,05), and reduced selenium levels (p<0,05). When zinc is supplemented to athletes, the relation between the duration and dose of supplementation is important. The results of the study indicated that zinc does not have any negative effect on the urinary excretion of the concerned elements. It can thus be concluded that athletes may benefit from zinc support. PMID:26826808

  8. Absorption of cumene through the respiratory tract and excretion of dimethylphenylcarbinol in urine.

    PubMed Central

    Seńczuk, W; Litewka, B

    1976-01-01

    Experiments on the absorption of cumene and the excretion of dimethylphenylcarbinol were made on 10 healthy volunteers, five men and five women aged between 20 and 35 years. They were exposed to cumene vapours 240, 480, 720 mg/m3 under controlled conditions. It was found that the average retention of cumene vapours was about 50% which tended to diminish at the end of each exposure. Based on these results, an exposure test that allows one to calculate the absorbed cumene dose during eight hours' work with a precision of about +/- 13.5% was achieved. PMID:1276088

  9. Use of In Vitro Absorption, Distribution, Metabolism, and Excretion (ADME) Data in Bioaccumulation Assessments for Fish

    SciTech Connect

    Nichols, John W.; Erhardt, Susan; Dyer, Scott; James, Margaret O.; Moore, Margo; Plotzke, Kathleen; Segner, Helmut; Schultz, Irvin R.; Thomas, Karluss; Vasiluk, Luba; Weisbrod, Anne V.

    2007-11-01

    A scientific workshop was held in 2006 to discuss the use of in vitro Absorption, Distribution, Metabolism, and Excretion (ADME) data in chemical bioaccumulation assessments for fish. Computer-based (in silico) modeling tools are widely used to estimate chemical bioaccumulation. These in silico methods have inherent limitations that result in inaccurate estimates for many compounds. Based on a review of the science workshop participants concluded that two factors, absorption and metabolism, represent the greatest sources of uncertainty in current bioaccumulation models. Both factors can be investigated experimentally using in vitro test systems.

  10. Urinary potassium excretion and risk of developing hypertension: the prevention of renal and vascular end-stage disease study.

    PubMed

    Kieneker, Lyanne M; Gansevoort, Ron T; Mukamal, Kenneth J; de Boer, Rudolf A; Navis, Gerjan; Bakker, Stephan J L; Joosten, Michel M

    2014-10-01

    Previous prospective cohort studies on the association between potassium intake and risk of hypertension have almost exclusively relied on self-reported dietary data, whereas repeated 24-hour urine excretions, as estimate of dietary uptake, may provide a more objective and quantitative estimate of this association. Risk of hypertension (defined as blood pressure ≥140/90 mm Hg or initiation of blood pressure-lowering drugs) was prospectively studied in 5511 normotensive subjects aged 28 to 75 years not using blood pressure-lowering drugs at baseline of the Prevention of Renal and Vascular End-Stage Disease (PREVEND) study. Potassium excretion was measured in two 24-hour urine specimens at baseline (1997-1998) and midway during follow-up (2001-2003). Baseline median potassium excretion was 70 mmol/24 h (interquartile range, 57-85 mmol/24 h), which corresponds to a dietary potassium intake of ≈91 mmol/24 h. During a median follow-up of 7.6 years (interquartile range, 5.0-9.3 years), 1172 subjects developed hypertension. The lowest sex-specific tertile of potassium excretion (men: <68 mmol/24 h; women: <58 mmol/24 h) had an increased risk of hypertension after multivariable adjustment (hazard ratio, 1.20; 95% confidence interval, 1.05-1.37), compared with the upper 2 tertiles (Pnonlinearity=0.008). The proportion of hypertension attributable to low potassium excretion was 6.2% (95% confidence interval, 1.7%-10.9%). No association was found between the sodium to potassium excretion ratio and risk of hypertension after multivariable adjustment. Low urinary potassium excretion was associated with an increased risk of developing hypertension. Dietary strategies to increase potassium intake to the recommended level of 90 mmol/d may have the potential to reduce the incidence of hypertension.

  11. Magnesium, zinc, arsenic, selenium and platinum urinary excretion from cancer patients of Antofagasta region, Chile: multi-metal approach

    PubMed Central

    Pizarro, I; Rivera, L; Ávila, J; Cortés, P

    2016-01-01

    Objectives To evaluate the short-term 24 h urinary excretion of platinum, arsenic, selenium, magnesium and zinc in patients with lung cancer and with cancer other than lungs treated with cisplatin or/and carboplatin from Antofagasta, Chile. Design Urine measurements of Pt and Se were made by inductively coupled plasma optical emission spectrometry, As by hydride-generation atomic absorption spectrometry and Mg and Zn by means of flame furnace atomic absorption spectrometry. Setting All samples were provided by the Oncological Centre of Antofagasta Regional Hospital (Region of Antofagasta, Chile). Participants Ninety 24-h urine samples from cancer patients after the infusion of Pt-base drugs and 10 24-h urine samples from cancer patients not treated with metal-base drugs. Main outcome measures Concentrations of Pt, Se, As, Zn and Mg coming from 24-h urine samples. Results Pt excreted was not significantly different between patients with lung and other cancers treated with cisplatin. The excretion of Mg, Zn and Se was greater than As. Then, Pt favours the excretion of essential elements. For lung and other types of cancers treated with drugs without Pt, excretion of Mg, Zn and Se was also greater than that of As, suggesting antagonism Mg-Zn-Se–anti-cancer drug relationship. Conclusions The amounts of Mg, Zn and Se excreted were greater than for As either with or without Pt-containing drugs, suggesting antagonist Mg-Zn-Se–anti-cancer drug relationships. The excretion of As, Mg, Zn and Se is induced by Pt. Knowledge obtained can contribute to understanding the arsenic cancer mechanism and the As-Mg-Zn-Se-Pt inter-element association for lung cancer and other types of cancer. PMID:27757244

  12. The Reduction in Urinary Glutamate Excretion Is Responsible for Lowering Urinary pH in Pink Urine Syndrome.

    PubMed

    Ogawa, Susumu; Takiguchi, Junko; Shimizu, Manami; Nako, Kazuhiro; Okamura, Masashi; Kinouchi, Yoshitaka; Ito, Sadayoshi

    2016-01-01

    We frequently encounter brownish-red, cloudy urine in some obese subjects, which occurs due to pink urine syndrome (PUS). PUS is a phenomenon in which uric acid precipitates into the urine due to reduced urinary pH (UpH). The mechanism underlying urinary acidification has not been elucidated so far. UpH level is adjusted by urinary excretion of ammonia synthesized from glutamate or glutamine, suggesting that renal synthesis of ammonia from glutamate or glutamine is decreased in PUS. However, this hypothesis has not been examined yet. We therefore examined the changes in the urinary excretion of these amino acids in PUS. One-hundred-fifty male students who had undergone a physical examination were enrolled. To determine the presence [PUS (+), n = 72] or absence [PUS (-), n = 78] of PUS, urinary amino acid excretion and UpH were evaluated. Independent risk factors of lower UpH were determined using multiple regression analyses. The PUS (+) subjects, who had lower UpH values than PUS (-) subjects, showed lower urinary excretion of glutamate and some other glucogenic amino acids. Thus, UpH correlated positively with the urinary excretion of glutamate in the PUS (+) subjects. A reduction in urinary glutamate but not in glutamine excretion proved to be an independent risk factor for reduced UpH. In conclusion, PUS appears to occur when a reduction in the synthesis of ammonia from glutamate causes a decrease in UpH. Our results showed that urinary glutamate excretion was reduced in PUS because renal glutamate was consumed by a reaction different from ammonia production. PMID:27238623

  13. Urinary excretion of LH and testosterone from male rats during exposure to increased gravity: post-spaceflight and centrifugation

    NASA Technical Reports Server (NTRS)

    Ortiz, R. M.; Wade, C. E.; Morey-Holton, E.

    2000-01-01

    A dissociation between plasma luteinizing hormone (LH) and testosterone (T) appears to exist during exposure to altered gravity. The pulsatile nature of LH release and the diurnal variability of T secretion may mask or bias the effects of altered gravity on the pituitary-gonadal axis when analyzing plasma concentrations. Therefore, we examined the relationship between the excretion of urinary LH and T in male Sprague-Dawley rats during exposure to increased gravity upon return to Earth following a 14-day spaceflight (n = 6) and by 12 days of centrifugation at 2g (n = 8). Excreted LH and T were elevated on the first 3 days postflight. Excreted T was elevated between Days 1 and 8 of centrifugation; however, excreted LH was reduced on Days 2 and 3 compared with control animals. Excreted LH and T were significantly correlated (R = 0.731 and 0.706, respectively) in postspaceflight and centrifuged animals. Correlation curves had similar slopes (0.0213 and 0.023, respectively), but different y-intercepts (-1.43 and 3.32, respectively). The sustained increase in excreted T during centrifugation suggests that the pituitary-gonadal axis in postspaceflight animals may adapt quicker to increased gravity. The upward shift in the correlation curve exhibited by the centrifuged animals suggests that the sensitivity of LH-induced T release is increased in these animals. The previous dissociation between plasma LH and T during altered gravity was not observed in the present study in which excreted LH and T were measured.

  14. The Kinetics of Urinary Fumonisin B1 Excretion in Humans Consuming Maize-Based Diets

    PubMed Central

    Riley, Ronald T.; Torres, Olga; Showker, Jency L.; Zitomer, Nicholas C.; Matute, Jorge; Voss, Kenneth A.; Gelineau-van Waes, Janee; Maddox, Joyce R.; Gregory, Simon G.; Ashley-Koch, Allison E.

    2013-01-01

    Fumonisins (FB) are mycotoxins found in maize. The purpose of this study was to 1) determine the relationship between FB1, FB2 and FB3 intake and urinary excretion in humans, 2) validate a method to isolate urinary FB on C18-SPE cartridges for international shipment, and 3) test the method using samples from Guatemala. Volunteers (n=10) consumed 206 grams/day of tortillas and biscuits prepared from masa flour and a product containing maize flour. Volunteers estimated their daily urine output and samples were analyzed for FB1, FB2 and FB3 and hydrolyzed FB1. Only FB1 was detected in urine suggesting lower absorption of FB2 and FB3. Excretion was highly variable peaking soon after consumption began and decreasing rapidly after consumption stopped. Within five days after consumption ended FB1 was not detected in urine. In a study with eight volunteers, the average total urinary FB1 was 0.5% of the intake. FB1 was detected in 61% (107/177) of the samples collected in Guatemala. The results support the use of urinary FB1 to assess ongoing exposure in population based studies. However, relating the FB1 concentration in urine to dietary intake of FB by individual subjects will be complicated due to inter-individual variability and the rapidity of clearance. PMID:22815244

  15. Increased cadmium excretion in metal-adapted populations of the midge Chironomus riparius (Diptera)

    SciTech Connect

    Postma, J.F.; Nugteren, P. van; Buckert-De Jong, M.B.

    1996-03-01

    Cadmium kinetics were studied in cadmium-adapted and nonadapted field populations of the midge Chironomus riparius. Accumulation and elimination experiments were carried out using first-generation laboratory-reared animals. Differences between populations were, therefore, assumed to have a genetic basis. Larvae were dissected to analyze the guts and the remainder of the larvae separately. First-order one-compartment models were not always successful in describing accumulation processes, probably due to acclimation. No interpopulation differences were observed in larval development based on dry weights, whereas some differences existed based on pupation rate. In most cases more than 80% of the total amount of cadmium was found in the guts of all populations. Larvae from cadmium-adapted populations showed a decreased net accumulation rate as well as higher equilibrium values (15--20%) compared to nonadapted populations. In addition, cadmium excretion efficiency was increased for cadmium-adapted larvae, which was due to an increased elimination rate from the guts. It was concluded that exposure to high cadmium concentrations in the field resulted in populations of C. riparius with an increased storage capability and an increased excretion efficiency, especially regarding the guts.

  16. Biliary excretion of curcumin is mediated by multidrug resistance-associated protein 2.

    PubMed

    Lee, Joo Hyun; Oh, Ju-Hee; Lee, Young-Joo

    2012-01-01

    Curcumin has a wide spectrum of pharmacological activities, including antioxidant, anti-inflammatory, antimicrobial, and anticancer properties. Recently, its potential as effective chemoprevention against cholangiocarcinoma, a highly malignant tumor of the bile duct with limited therapeutic options, was reported. The purpose of the present study was to investigate the contribution of multidrug resistance-associated protein 2 (Mrp2) to the biliary excretion of curcumin using Sprague-Dawley rats (SDR) and Eisai hyperbilirubinemic rats (EHBR). After intravenous administration of curcumin with a loading dose of 4.5 mg/kg, followed by a constant infusion of 18 mg/kg/h to the SDR and EHBR, the pharmacokinetic parameters of curcumin were estimated. In EHBR, the total area under the bile concentration-time curve from 0 to 80 min following curcumin administration was dramatically decreased (0.094%) compared to that in SDR. In addition, the plasma-to-bile and liver-to-bile clearances were both significantly decreased compared to SDR. These results provide the first evidence that Mrp2 mediates the biliary excretion of curcumin and thus may be a major factor in the control of exposure of curcumin to the bile duct. This study may be helpful to the potential use of curcumin as a treatment for bile duct cancer, and to understanding the genetic polymorphism of Mrp2 for clinical trials of curcumin.

  17. Dapagliflozin twice daily or once daily: effect on pharmacokinetics and urinary glucose excretion in healthy subjects.

    PubMed

    Tang, W; Reele, S; Hamer-Maansson, J E; Parikh, S; de Bruin, T W A

    2015-04-01

    The primary objective of this single-centre, open-label crossover study (NCT01072578) was to assess the effect of dapagliflozin on the amount of glucose in the blood and urine in healthy volunteers when dapagliflozin was administered once a day (10 mg) versus twice a day (5 mg every 12 h) after 5 days of dosing. At steady state, the AUC(ss)₀₋₂₄ (area under the dapagliflozin curve (0-24 hours) at steady state), C(ss,av) (average concentration at steady state) between dapagliflozin 5 mg twice daily and 10 mg once daily were similar AUC(ss)₀₋₂₄ [5 mg bid, (458.0 (28.7)) and 10 mg qd, (470.0 (28.5))] and C(ss,av) [5 mg bid 18.8 (28.9)) and 10 mg qd, (19.6(28.5))], but minimum and maximum plasma levels of dapagliflozin differed significantly. Percent inhibition of renal glucose reabsorption (%IRGRA) and total urinary glucose excretion over 24 h were similar for both doses. The relationship between the mean dapagliflozin concentration and %IRGRA and the total urinary glucose excreted was well described by a maximum effect model. The results indicate that dapagliflozin may be used for either once daily or twice daily administration.

  18. Urinary Excretion of Phenolic Acids by Infants and Children: A Randomised Double-Blind Clinical Assay

    PubMed Central

    Uberos, J.; Fernández-Puentes, V.; Molina-Oya, M.; Rodríguez-Belmonte, R.; Ruíz-López, A.; Tortosa-Pinto, P.; Molina-Carballo, A.; Muñoz-Hoyos, A.

    2012-01-01

    Objectives: The present study, which is part of the ISRCTN16968287 clinical assay, is aimed at determining the effects of cranberry syrup or trimethoprim treatment for UTI. Methods: This Phase III randomised clinical trial was conducted at the San Cecilio Clinical Hospital (Granada, Spain) with a study population of 192 patients, aged between 1 month and 13 years. Criteria for inclusion were a background of recurrent UTI, associated or otherwise with vesico-ureteral reflux of any degree, or renal pelvic dilatation associated with urinary infection. Each child was randomly given 0.2 mL/Kg/day of either cranberry syrup or trimethoprim (8 mg/mL). The primary and secondary objectives, respectively, were to determine the risk of UTI and the levels of phenolic acids in urine associated with each intervention. Results: With respect to UTI, the cranberry treatment was non-inferior to trimethoprim. Increased urinary excretion of ferulic acid was associated with a greater risk of UTI developing in infants aged under 1 year (RR 1.06; CI 95% 1.024–1.1; P = 0.001). Conclusions: The results obtained show the excretion of ferulic acid is higher in infants aged under 1 year, giving rise to an increased risk of UTI, for both treatment options. PMID:23641168

  19. Radioactive excretion in human milk following administration of /sup 99m/Tc macroaggregated albumin

    SciTech Connect

    Pittard, W.B.; Merkatz, R.; Fletcher, B.D.

    1982-08-01

    Albumin-tagged sodium pertechnetate (technetium) is routinely used in nuclear medicine for scanning procedures of the lung. The rate of excretion of this radionuclide into breast milk and the resultant potential radiation hazard to the nursing infant have received little attention. Therefore the milk from a nursing mother who required a lung scan because of suspected pulmonary emboli using an intravenous injection of 4 mCi of /sup 99m/Tc macroaggregated human serum albumin was monitored. Albumin tagging severely limited the entrance of technetium into her milk and the radioactivity of the milk returned to base line by 24 hours. A total of 2.02 muCi of technetium was measured in the 24-hour milk collection after technetium injection and 94% of this amount was excreted by 15.5 hours. This amount of technetium administered orally to a newborn would deliver a total body radiation dose of .3 mrad. Therefore, an infant would receive trivial doses of radiation if breast-feeding were resumed 15.5 hours after administration of the radionuclide to the mother and nursing can clearly be resumed safely 24 hours after injection.

  20. Temporal dynamics of seed excretion by wild ungulates: implications for plant dispersal

    PubMed Central

    Picard, Mélanie; Papaïx, Julien; Gosselin, Frédéric; Picot, Denis; Bideau, Eric; Baltzinger, Christophe

    2015-01-01

    Dispersal is a key process in metapopulation dynamics as it conditions species’ spatial responses to gradients of abiotic and biotic conditions and triggers individual and gene flows. In the numerous plants that are dispersed through seed consumption by herbivores (endozoochory), the distance and effectiveness of dispersal is determined by the combined effects of seed retention time in the vector’s digestive system, the spatial extent of its movements, and the ability of the seeds to germinate once released. Estimating these three parameters from experimental data is therefore crucial to calibrate mechanistic metacommunity models of plant–herbivore interactions. In this study, we jointly estimated the retention time and germination probability of six herbaceous plants transported by roe deer (Capreolus capreolus), red deer (Cervus elaphus), and wild boar (Sus scrofa) through feeding experiments and a Bayesian dynamic model. Retention time was longer in the nonruminant wild boar (>36 h) than in the two ruminant species (roe deer: 18–36 h, red deer: 3–36 h). In the two ruminants, but not in wild boar, small and round seeds were excreted faster than large ones. Low germination probabilities of the excreted seeds reflected the high cost imposed by endozoochory on plant survival. Trait-mediated variations in retention time and germination probability among animal and plant species may impact plant dispersal distances and interact with biotic and abiotic conditions at the release site to shape the spatial patterns of dispersed plant species. PMID:26257875

  1. Tissue accumulation and urinary excretion of Cr in chromium picolinate (CrPic)-supplemented lambs.

    PubMed

    Dallago, Bruno Stéfano Lima; Lima, Bárbara Alcântara Ferreira; Braz, Shélida Vasconcelos; Mustafa, Vanessa da Silva; McManus, Concepta; Paim, Tiago do Prado; Campeche, Aline; Gomes, Edgard Franco; Louvandini, Helder

    2016-05-01

    Chromium (Cr) concentrations in liver, kidney, spleen, heart, lymph node, skeletal muscle, bone, testis and urine of lambs were measured to trace the biodistribution and bioaccumulation of Cr after oral supplementation with chromium picolinate (CrPic). Twenty-four Santa Inês lambs were treated with four different concentrations of CrPic: placebo, 0.250, 0.375 and 0.500 mg of CrPic/animal/day for 84 days. The basal diet consisted of Panicum maximum cv Massai hay and concentrate. Cr concentrations were measured by ICP-MS measuring (52)Cr as collected mass. There was a positive linear relationship between dose administered and the accumulation of Cr in the heart, lungs and testis. Urinary excretion of Cr occurred in a time and dose-dependent manner, so the longer or more dietary Cr provided, the greater excretion of the element. As some non-carcass components (such as lungs or heart) are added to bone and visceral meal to feed animals, there is a risk of bioaccumulation and biomagnification due to Cr offered as CrPic in the diet.

  2. Calcium supplementation: effect on blood pressure and urinary mineral excretion in normotensive male lactoovovegetarians and omnivores.

    PubMed

    Aalberts, J S; Weegels, P L; van der Heijden, L; Borst, M H; Burema, J; Hautvast, J G; Kouwenhoven, T

    1988-07-01

    After an initial 4-wk period, 36 healthy male subjects aged 19-28 y (14 lactoovovegetarians and 22 omnivores) were given a supplement to their usual diet of 27.9 mmol calcium/d for 5 wk. During this period 22 blood pressure measurements were taken and 30 24-h urine specimens and 15 24-h dietary records were obtained. Base-line blood pressures did not differ significantly between vegetarians and omnivores (118.3/59.3 and 119.5/60.7, respectively). At the end of the supplementation period there was a decrease in diastolic blood pressure of 1.4 mm Hg (p less than 0.10) and an unexpected increase in systolic blood pressure of 2.1 mm Hg (p less than 0.01) in the omnivores. Although not significant, the same trends were observed in the vegetarians. In both groups Ca and magnesium excretions increased significantly and phosphorus excretion decreased significantly. Blood pressure of normotensive subjects with high basal Ca intake may not be sensitive to Ca supplementation.

  3. Effect of penicillic acid on biliary excretion of indocyanine green in the mouse and rat.

    PubMed

    Chan, P K; Hayes, A W

    1981-02-01

    Penicillic acid (PA), a mycotoxin, is hepatotoxic. A study was undertaken to investigate its effects on hepatobiliary excretory function, using the anionic compounds indocyanine green (ICG), in mice and rats. Pretreatment with a single dose of PA (90 mg/kg, ip, an LD50 dose in both species) resulted in depression of ICG excretion in both species. This depression was dose- and time-dependent. Decreases of 42 and 57% in biliary excretion of ICG were observed in rats and mice 48 and 72 h after PA pretreatment, respectively. Although bile flow was depressed significantly when expressed in terms of body weight, it was not altered in mice when expressed in terms of liver weight. Bile flow was not affected in rats. While the serum ICG concentration was increased after PA treatment in both species, the liver ICG concentration was not affected. The liver-to-serum, bile-to-serum, and bile-to-liver ICG concentration ratios decreased in PA-treated animals. These data suggest that the PA-induced hepatobiliary excretory dysfunction may result from depression of both uptake of ICG into the liver and bile canlicular transport of ICG.

  4. Bioassay data and a retention-excretion model for systemic plutonium

    SciTech Connect

    Leggett, R.W.

    1984-05-01

    The estimation of systemic burdens from urinalyses has been the most common and useful method of quantifying occupational exposures to plutonium. Problems arise in using this technique, however, because of inadequate modeling of human retention, translocation, and excretion of this element. Present methods for estimating the systemic burden from urinalyses were derived to a large extent from patterns observed in the first few months after exposure, but there is now evidence that these same patterns do not persist over long periods. In this report we collect and discuss data needed for the interpretation of bioassay results for Pu. These data are used to develop a model that describes the movement, retention, and excretion of systemic Pu in the human body in terms of explicitly identified anatomical compartments. This model may be used in conjunction with existing models and/or case-specific information concerning the translocation of Pu from the respiratory or gastrointestinal tract or from wounds to the bloodstream. Attention is restricted to the behavior of Pu after it has gained access to the bloodstream. There remain significant uncertainties concerning some aspects of the movement of Pu, particularly its translocation from the liver. An attempt has been made to construct the model in such a way as to elucidate those areas needing further attention. 98 references, 18 figures, 16 tables.

  5. Colestilan decreases weight gain by enhanced NEFA incorporation in biliary lipids and fecal lipid excretion.

    PubMed

    Sugimoto-Kawabata, Kanami; Shimada, Hiroshi; Sakai, Kaoru; Suzuki, Kazuo; Kelder, Thomas; Pieterman, Elsbet J; Cohen, Louis H; Havekes, Louis M; Princen, Hans M; van den Hoek, Anita M

    2013-05-01

    Bile acid sequestrants (BASs) are cholesterol-lowering drugs that also affect hyperglycemia. The mechanism by which BASs exert these and other metabolic effects beyond cholesterol lowering remains poorly understood. The present study aimed to investigate the effects of a BAS, colestilan, on body weight, energy expenditure, and glucose and lipid metabolism and its mechanisms of action in high-fat-fed hyperlipidemic APOE*3 Leiden (E3L) transgenic mice. Mildly insulin-resistant E3L mice were fed a high-fat diet with or without 1.5% colestilan for 8 weeks. Colestilan treatment decreased body weight, visceral and subcutaneous fat, and plasma cholesterol and triglyceride levels but increased food intake. Blood glucose and plasma insulin levels were decreased, and hyperinsulinemic-euglycemic clamp analysis demonstrated improved insulin sensitivity, particularly in peripheral tissues. In addition, colestilan decreased energy expenditure and physical activity, whereas it increased the respiratory exchange ratio, indicating that colestilan induced carbohydrate catabolism. Moreover, kinetic analysis revealed that colestilan increased [(3)H]NEFA incorporation in biliary cholesterol and phospholipids and increased fecal lipid excretion. Gene expression analysis in liver, fat, and muscle supported the above findings. In summary, colestilan decreases weight gain and improves peripheral insulin sensitivity in high-fat-fed E3L mice by enhanced NEFA incorporation in biliary lipids and increased fecal lipid excretion.

  6. Urinary excretion of 3-methyladenine after consumption of fish containing high levels of dimethylamine.

    PubMed

    Fay, L B; Leaf, C D; Gremaud, E; Aeschlimann, J M; Steen, C; Shuker, D E; Turesky, R J

    1997-05-01

    The urinary excretion of the DNA alkylation product, 3-methyladenine (3-MeAde), was measured in human volunteers who were on controlled diets and consumed fresh fish, or frozen-stored fish that contained 50-fold higher levels of dimethylamine (DMA), with or without ingested nitrate. DMA potentially could react with nitrosating agents in the diet or within the body, and produce the potent carcinogen N-nitrosodimethylamine (NDMA), which can then react with DNA to form several adducts including 3-MeAde. Our findings show that there was no increase in urinary levels of 3-MeAde after consumption of fish preserved by frozen storage relative to levels after consumption of fresh fish. Furthermore, consumption of 225 mg sodium nitrate (equal to the nitrate content in a large glass of beet juice) at 1 h prior to consumption of the frozen-stored fish did not increase urinary 3-MeAde levels as would be expected if nitrate enhanced endogenous nitrosation of DMA. In contrast, urinary excretion of 3-MeAde from a volunteer who was a moderate cigarette smoker (11 cigarettes per day) was approximately 3- to 8-fold higher than dietary 3-MeAde intake. These findings indicate that consumption of high levels of DMA in fish does not result in detectable levels of NDMA formation and genetic damage as measured by the urinary biomarker 3-MeAde. PMID:9163693

  7. Effect of penicillin on fatty acid synthesis and excretion in Streptococcus mutans BHT

    SciTech Connect

    Brissette, J.L.; Pieringer, R.A.

    1985-03-01

    Treatment of exponentially growing cultures of Streptococcus mutans BHT with growth-inhibitory concentrations (0.2 microgram/ml) of benzylpenicillin stimulates the incorporation of (2-/sup 14/C) acetate into lipids excreted by the cells by as much as 69-fold, but does not change the amount of /sup 14/C incorporated into intracellular lipids. At this concentration of penicillin cellular lysis does not occur. The radioactive label is incorporated exclusively into the fatty acid moieties of the glycerolipids. During a 4-hr incubation in the presence of penicillin, the extracellular fatty acid ester concentration increases 1.5 fold, even though there is no growth or cellular lysis. An indication of the relative rate of fatty acid synthesis was most readily obtained by placing S. mutans BHT in a buffer containing /sup 14/C-acetate. Under these nongrowing conditions free fatty acids are the only lipids labeled, a factor which simplifies the assay. The addition of glycerol to the buffer causes all of the nonesterified fatty acids to be incorporated into glycerolipid. The cells excrete much of the lipid whether glycerol is present or not. Addition of penicillin to the nongrowth supporting buffer system does not stimulate the incorporation of (/sup 14/C)-acetate into fatty acids.

  8. Depression of biliary glutathione excretion by chronic ethanol feeding in the rat

    SciTech Connect

    Vendemiale, G.; Jayatilleke, E.; Shaw, S.; Lieber, C.S.

    1984-03-12

    The effects of chronic alcohol feeding on biliary glutathione excretion were studied in rats pair fed diets containing either ethanol (36% of total energy) or isocaloric carbohydrate for 4-6 weeks. An exteriorized biliary-duodenal fistula was established and total glutathione (GSH) and oxidized glutathione (GSSG) were measured. A significant decrease was observed in rats fed alcohol chronically compared to their pair fed controls in the biliary excretion of GSH (55.7 +/- 37.0 vs 243.1 +/- 29.0 ..mu..g/ml bile, p < 0.025) as well as biliary GSSG (12.5 +/- 5.0 vs 49.9 +/- 8.0 ..mu..g/ml bile, p < 0.05) and in bile flow (23.1 +/- 1.6 vs 29.2 +/- 1.3 ..mu..g/min, p < 0.05). An acute dose of ethanol tended to exaggerate the decrease on biliary GSH and GSSG in the two groups of animals. The depression in biliary GSH could not be attributed to decreased GSH synthesis since S/sup 35/-L-methionine incorporation into hepatic and biliary GSH was unchanged or even increased after chronic ethanol feeding. 22 references, 4 figures.

  9. Development of an excretion care support robot with human cooperative characteristics.

    PubMed

    Yina Wang; Shuoyu Wang

    2015-08-01

    To support care giving in an aging society with a shrinking population, various life support robots are being developed. In the authors' laboratory, an excretion care support robot (ECSR) with human cooperative characteristic has been developed to relieve the burden of caregivers and improve the quality of life for bedridden persons. This robot consists of a portable toilet with storage tank and a mobile robot which can run autonomously to conduct the cooperative work with others. Our research is focused on how to improve the motion accuracy and how the robot can cooperate with users. In this paper, to enable the ECSR could precisely move in the indoor environment, a proper controller is proposed considering the center of gravity shift and load changes. Then, to perform the cooperative task, two acceleration sensors are used to recognize the users' intended posture and position when moving from bed to toilet. The robot's target angle and position are determined by the user's posture. The effectiveness of the proposed method is verified by a pseudo excretion support experiment. PMID:26737871

  10. Importance of Residual Water Permeability on the Excretion of Water during Water Diuresis in Rats

    PubMed Central

    Cheema-Dhadli, Surinder; Chong, Chee Keong; Kim, Namhee; Kamel, Kamel S

    2010-01-01

    When the concentration of sodium (Na+) in arterial plasma (PNa) declines sufficiently to inhibit the release of vasopressin, water will be excreted promptly when the vast majority of aquaporin 2 water channels (AQP2) have been removed from luminal membranes of late distal nephron segments. In this setting, the volume of filtrate delivered distally sets the upper limit on the magnitude of the water diuresis. Since there is an unknown volume of water reabsorbed in the late distal nephron, our objective was to provide a quantitative assessment of this parameter. Accordingly, rats were given a large oral water load, while minimizing non-osmotic stimuli for the release of vasopressin. The composition of plasma and urine were measured. The renal papilla was excised during the water diuresis to assess the osmotic driving force for water reabsorption in the inner medullary collecting duct. During water diuresis, the concentration of creatinine in the urine was 13-fold higher than in plasma, which implies that ~8% of filtered water was excreted. The papillary interstitial osmolality was 600 mOsm/L > the urine osmolality. Since 17% of filtered water is delivered to the earliest distal convoluted tubule micropuncture site, we conclude that half of the water delivered to the late distal nephron is reabsorbed downstream during water diuresis. The enormous osmotic driving force for the reabsorption of water in the inner medullary collecting duct may play a role in this reabsorption of water. Possible clinical implications are illustrated in the discussion of a case example. PMID:21468191

  11. Importance of Residual Water Permeability on the Excretion of Water during Water Diuresis in Rats.

    PubMed

    Cheema-Dhadli, Surinder; Chong, Chee Keong; Kim, Namhee; Kamel, Kamel S; Halperin, Mitchell L

    2010-06-01

    When the concentration of sodium (Na(+)) in arterial plasma (P(Na)) declines sufficiently to inhibit the release of vasopressin, water will be excreted promptly when the vast majority of aquaporin 2 water channels (AQP2) have been removed from luminal membranes of late distal nephron segments. In this setting, the volume of filtrate delivered distally sets the upper limit on the magnitude of the water diuresis. Since there is an unknown volume of water reabsorbed in the late distal nephron, our objective was to provide a quantitative assessment of this parameter. Accordingly, rats were given a large oral water load, while minimizing non-osmotic stimuli for the release of vasopressin. The composition of plasma and urine were measured. The renal papilla was excised during the water diuresis to assess the osmotic driving force for water reabsorption in the inner medullary collecting duct. During water diuresis, the concentration of creatinine in the urine was 13-fold higher than in plasma, which implies that ~8% of filtered water was excreted. The papillary interstitial osmolality was 600 mOsm/L > the urine osmolality. Since 17% of filtered water is delivered to the earliest distal convoluted tubule micropuncture site, we conclude that half of the water delivered to the late distal nephron is reabsorbed downstream during water diuresis. The enormous osmotic driving force for the reabsorption of water in the inner medullary collecting duct may play a role in this reabsorption of water. Possible clinical implications are illustrated in the discussion of a case example. PMID:21468191

  12. Effect of prolactin on urinary excretion and renal haemodynamics in conscious rats.

    PubMed Central

    Bliss, D J; Lote, C J

    1982-01-01

    1. Conscious rats received a saline infusion (5.8 ml . hr-1) via a tail vein, for a 6 hr period. For the final 2 hr of this infusion period, prolactin (7.1 microgram (100 g body wt.)-1 . hr-1) was incorporated in the infusate. A control group of animals continued to receive saline alone. 2. In the first hour of prolactin administration (in comparison with the control group), urine flow, sodium output and osmolal output were all significantly reduced (P less than 0.02); there was also a reduction (P less than 0.05) in renal plasma flow (p-amino-hippurate clearance), but the filtration fraction did not alter. The changes in urinary excretion, and in renal haemodynamics, did not persist for the second hour of prolactin administration, but there was a sustained increase in body fluid volume. 3. It is possible that altered renal haemodynamics are responsible for the reduced urinary water and solute excretion which occurs during acute prolactin administration. PMID:7069622

  13. Impaired sodium excretion and salt-sensitive hypertension in corin-deficient mice.

    PubMed

    Wang, Wei; Shen, Jianzhong; Cui, Yujie; Jiang, Jingjing; Chen, Shenghan; Peng, Jianhao; Wu, Qingyu

    2012-07-01

    Corin is a protease that activates atrial natriuretic peptide, a cardiac hormone important in the control of blood pressure and salt-water balance. Here we examined the role of corin in regulating blood pressure and sodium homeostasis upon dietary salt challenge. Radiotelemetry-tracked blood pressure in corin knockout mice on a high-salt diet (4% sodium chloride) was significantly increased; however, there was no such change in similarly treated wild-type mice. In the knockout mice on the high-salt diet there was an impairment of urinary sodium excretion and an increase in body weight, but no elevation of plasma renin or serum aldosterone levels. When the knockout mice on the high-salt diet were treated with amiloride, an epithelial sodium channel blocker that inhibits renal sodium reabsorption, the impaired urinary sodium excretion and increased body weight were normalized. Amiloride treatment also reduced high blood pressure caused by the high-salt diet in these mice. Thus, the lack of corin in mice impairs their adaptive renal response to high dietary salt, suggesting that corin deficiency may represent an important mechanism underlying salt-sensitive hypertension. PMID:22418978

  14. Plutonium excretion in urine of residents living near the Rocky Flats Environmental Technology Site.

    PubMed

    Ibrahim, S A; Whicker, F W; Reuss, S K; Whicker, R D; Chapman, P L; Krahenbuhl, M P

    1999-04-01

    An assessment of current levels of 239Pu in individuals living near the Rocky Flats Environmental Technology Site was conducted. Long-term residents of areas adjacent to the Site, as well as people living well beyond any expected influence of the site, provided urine samples, which were analyzed by fission track analysis for the levels of 239Pu. The Rocky Flats Environmental Technology Site vicinity participants were selected for maximum possible exposure to environmental plutonium by virtue of residence location, length of residence, age, and outdoor lifestyle. The mean 239Pu excretion rate in urine estimated for the entire Rocky Flats group was 1.1 microBq d(-1), in contrast to that estimated for the background group (0.85 microBq d(-1)). The estimated median 239Pu excretion rate for the Rocky Flats group was 1.1 microBq d(-1), compared to 0.54 microBq d(-1) for the background group. Both parametric and non-parametric tests indicated that these differences were not statistically significant (alpha = 0.05). Measured levels of 239Pu in urine from the Rocky Flats group were low and well within the range of reported "background" values, indicating small doses and low health risks. The fission track analysis technique may not be sufficiently accurate or precise to allow definitive comparisons between two groups of subjects with near-background levels of 239Pu in urine. PMID:10086597

  15. Importance of Residual Water Permeability on the Excretion of Water during Water Diuresis in Rats.

    PubMed

    Cheema-Dhadli, Surinder; Chong, Chee Keong; Kim, Namhee; Kamel, Kamel S; Halperin, Mitchell L

    2010-06-01

    When the concentration of sodium (Na(+)) in arterial plasma (P(Na)) declines sufficiently to inhibit the release of vasopressin, water will be excreted promptly when the vast majority of aquaporin 2 water channels (AQP2) have been removed from luminal membranes of late distal nephron segments. In this setting, the volume of filtrate delivered distally sets the upper limit on the magnitude of the water diuresis. Since there is an unknown volume of water reabsorbed in the late distal nephron, our objective was to provide a quantitative assessment of this parameter. Accordingly, rats were given a large oral water load, while minimizing non-osmotic stimuli for the release of vasopressin. The composition of plasma and urine were measured. The renal papilla was excised during the water diuresis to assess the osmotic driving force for water reabsorption in the inner medullary collecting duct. During water diuresis, the concentration of creatinine in the urine was 13-fold higher than in plasma, which implies that ~8% of filtered water was excreted. The papillary interstitial osmolality was 600 mOsm/L > the urine osmolality. Since 17% of filtered water is delivered to the earliest distal convoluted tubule micropuncture site, we conclude that half of the water delivered to the late distal nephron is reabsorbed downstream during water diuresis. The enormous osmotic driving force for the reabsorption of water in the inner medullary collecting duct may play a role in this reabsorption of water. Possible clinical implications are illustrated in the discussion of a case example.

  16. Increased lactulose/rhamnose ratio during fluid load is caused by increased urinary lactulose excretion.

    PubMed

    Hallemeesch, M M; Lamers, W H; Soeters, P B; Deutz, N E

    2000-01-01

    Noninvasive assessment of intestinal permeability in vivo is based on the measurement of urinary excretion of orally administered sugar probes. It is expressed as a ratio, usually lactulose/rhamnose or 3-O-methyl-D-glucose (3-OMG)/rhamnose. In both endotoxemic and control rats that were receiving fluid, we observed an increase in the recovery of lactulose and 3-OMG but not rhamnose in both groups, suggesting an enhancement of intestinal permeability. In the measurement of intestinal permeability, all pre- and postmucosal factors are considered equal for all sugars. We hypothesized that postmucosal factors and not changes in intestinal permeability caused the increased urinary lactulose and 3-OMG recoveries observed during fluid loading. Therefore, the effects of fluid loading on urinary excretion of the sugar probes were studied in healthy rats receiving the sugars intravenously. After intravenous injection, fluid loading increased urinary lactulose recovery threefold but not that of 3-OMG and rhamnose. In conclusion, fluid loading increases the lactulose/rhamnose ratio independent of changes in intestinal permeability. The 3-OMG/rhamnose ratio is not influenced by fluid loading.

  17. Effects of season on the bathypelagic mysid Gnathophausia ingens: water content, respiration, and excretion

    NASA Astrophysics Data System (ADS)

    Hiller-Adams, Page; Childress, James J.

    1983-06-01

    Water contents, oxygen consumption rates and ammonia excretion rates of individuals of the large bathypelagic mysid Gnathophausia ingens were measured as a function of size and season (winter and summer). Individuals of the sizes studied live permanently beneath the euphotic zone. Water content, as a percent of wet weight, is higher in winter than in summer, suggesting seasonal variability in the midwater environment. Our data suggest that the seasonal change in water content increases with increasing size. We suggest that the changes are due in part to seasonal changes in food intake. Seasonal differences were not observed in wet-weight-specific rates of either respiration or ammonia excretion. Both rates decrease with increasing size. The constancy of the atomic O:N ratio and its high value (geometric mean = 44.3) indicate that the average proportions of lipid and protein metabolized by individuals were independent of size and season and that lipid stores were not sufficiently depleted, even in small animals, to cause a shift to predominantly protein metabolism in winter or summer. On the average, metabolic rates of individuals were unaffected by seasonal variation in the midwater environment.

  18. Tissue accumulation and urinary excretion of Cr in chromium picolinate (CrPic)-supplemented lambs.

    PubMed

    Dallago, Bruno Stéfano Lima; Lima, Bárbara Alcântara Ferreira; Braz, Shélida Vasconcelos; Mustafa, Vanessa da Silva; McManus, Concepta; Paim, Tiago do Prado; Campeche, Aline; Gomes, Edgard Franco; Louvandini, Helder

    2016-05-01

    Chromium (Cr) concentrations in liver, kidney, spleen, heart, lymph node, skeletal muscle, bone, testis and urine of lambs were measured to trace the biodistribution and bioaccumulation of Cr after oral supplementation with chromium picolinate (CrPic). Twenty-four Santa Inês lambs were treated with four different concentrations of CrPic: placebo, 0.250, 0.375 and 0.500 mg of CrPic/animal/day for 84 days. The basal diet consisted of Panicum maximum cv Massai hay and concentrate. Cr concentrations were measured by ICP-MS measuring (52)Cr as collected mass. There was a positive linear relationship between dose administered and the ac