[Kinetics of uptake of phosphates and nitrates by marine multicellular algae Gelidium latifolium (Grev.) Born. et Thur].

Science.gov (United States)

Silkin, V A; Chubchikova, I N

2007-01-01

We studied nonstationary kinetics of the uptake of phosphates and nitrates by the red marine algae Gelidium latifolium (Grev.) Born et Thur. and calculated constants of the Michaelis-Menten equation for these elements. In the area of 0-3 microM, the kinetics of phosphate consumption had the following coefficients: maximum rate of uptake 0.8 micromol/(g x h), constant of half-saturation 1.745 microM. For nitrate nitrogen at 0-30 microM, an adaptive strategy of uptake kinetics was noted with change of the equation parameters with time: after 1 h, the maximum rate of uptake was 5.1 micromol/(g x h) and constant of half-saturation 19 gM, while within 2 h, the maximum rate of uptake significantly increased. This could be related to the synthesis of nitrate reductase. Coupled with the uptake of nitrates, nonstationary kinetics of the release of nitrates in the surrounding medium had a one-peak pattern: the maximum concentration of nitrites in the medium and the time of its achievement increased with the initial concentration of nitrates. The maximum concentration of nitrites was 6 to 14% of the initial concentration in the medium.

Ozone uptake, water loss and carbon exchange dynamics in annually drought-stressed Pinus ponderosa forests: measured trends and parameters for uptake modeling.

Science.gov (United States)

Panek, Jeanne A

2004-03-01

This paper describes 3 years of physiological measurements on ponderosa pine (Pinus ponderosa Dougl. ex Laws.) growing along an ozone concentration gradient in the Sierra Nevada, California, including variables necessary to parameterize, validate and modify photosynthesis and stomatal conductance algorithms used to estimate ozone uptake. At all sites, gas exchange was under tight stomatal control during the growing season. Stomatal conductance was strongly correlated with leaf water potential (R2=0.82), which decreased over the growing season with decreasing soil water content (R2=0.60). Ozone uptake, carbon uptake, and transpirational water loss closely followed the dynamics of stomatal conductance. Peak ozone and CO2 uptake occurred in early summer and declined progressively thereafter. As a result, periods of maximum ozone uptake did not correspond to periods of peak ozone concentration, underscoring the inappropriateness of using current metrics based on concentration (e.g., SUM0, W126 and AOT40) for assessing ozone exposure risk to plants in this climate region. Both Jmax (maximum CO2-saturated photosynthetic rate, limited by electron transport) and Vcmax (maximum rate of Rubisco-limited carboxylation) increased toward the middle of the growing season, then decreased in September. Intrinsic water-use efficiency rose with increasing drought stress, as expected. The ratio of Jmax to Vcmax was similar to literature values of 2.0. Nighttime respiration followed a Q10 of 2.0, but was significantly higher at the high-ozone site. Respiration rates decreased by the end of the summer as a result of decreased metabolic activity and carbon stores.

Factors influencing the in vitro uptake of mercury vapour in blood

Energy Technology Data Exchange (ETDEWEB)

Kudsk, F.N.

1969-01-01

The influence of a number of factors on the in vitro uptake of mercury vapour in blood has been investigated in order to clarify the mechanism by which mercury is oxidized in blood. The rate of mercury uptake in blood in a pure oxygen atmosphere is moderately increased, but somewhat decreased in a nitrogen atmosphere when compared with the rate of uptake in an atmospheric air phase. Increasing concentrations of methylene blue induce a very pronounced acceleration of the rate of mercury uptake in blood up to a maximum of about 10 times the normal uptake in an atmospheric air phase. Menadione shows a similar, but even more pronounced effect. The menadione-stimulated uptake is markedly inhibited by low concentrations of ethyl alcohol. Concentrations of potassium cyanide from 1/8 x 10/sup -3/ to 4 x 10/sup -3/ M cause a progressive inhibition of the mercury uptake in the blood up to a maximum of about 60%, which is very similar to the effect produced by ethyl alcohol. The investigations point to hydrogen peroxide and oxidized glutathione as agents of importance in the oxidation and uptake of mercury vapour in blood. The way in which ethyl alcohol inhibits the uptake is still unknown. Some possible mechanisms are discussed. 24 references, 4 figures, 3 tables.

Maximum physical capacity testing in cancer patients undergoing chemotherapy

DEFF Research Database (Denmark)

Knutsen, L.; Quist, M; Midtgaard, J

2006-01-01

BACKGROUND: Over the past few years there has been a growing interest in the field of physical exercise in rehabilitation of cancer patients, leading to requirements for objective maximum physical capacity measurement (maximum oxygen uptake (VO(2max)) and one-repetition maximum (1RM)) to determin...... early in the treatment process. However, the patients were self-referred and thus highly motivated and as such are not necessarily representative of the whole population of cancer patients treated with chemotherapy....... in performing maximum physical capacity tests as these motivated them through self-perceived competitiveness and set a standard that served to encourage peak performance. CONCLUSION: The positive attitudes in this sample towards maximum physical capacity open the possibility of introducing physical testing...

Assessment of the phytoremediation potential of Panicum maximum ...

African Journals Online (AJOL)

Obvious signs of phyto-toxicity however appeared in plants exposed to 120 ppm Pb2+ and Cd2+ at day twenty-three, suggesting that P. maximum may be a moderate metal accumulator. Keywords: phytoremediation, heavy metals, uptake, tissues, accumulator. African Journal of Biotechnology, Vol 13(19), 1979-1984 ...

Developing Ecological Models on Carbon and Nitrogen in Secondary Facultative Ponds

Directory of Open Access Journals (Sweden)

Aponte-Reyes Alexander

2014-07-01

Full Text Available Ecological models formulated for TOC, CO2, NH4+, NO3- and NTK, based in literature reviewed and field work were obtained monitoring three facultative secondary stabilization ponds, FSSP, pilots: conventional pond, CP, baffled pond, BP, and baffled-meshed pond, BMP. Models were sensitive to flow inlet, solar radiation, pH and oxygen content; the sensitive parameters in Carbon Model were KCOT Ba, umax Ba, umax Al, K1OX, VAl, R1DCH4, YBh. The sensitive parameters in the Nitrogen model were KCOT Ba, umax Ba, umax Al, VAl, KOPH, KOPA, r4An. The test t–paired showed a good simulating of Carbon model refers to TOC in FSSP; on the other side, the Nitrogen model showed a good simulating of NH4+. Different topological models modify ecosystem ecology forcing different transformation pathways of Nitrogen; equal transformations of the Carbon BMP topology could be achieved using lower volumes, however, a calibration for a new model would be required. Carbon and Nitrogen models developed could be coupled to hydrodynamics models for better modeling of FSSP.

Tritium uptake kinetics in crayfish (Orconectes immunis)

International Nuclear Information System (INIS)

Patrick, P.H.

1985-06-01

Uptake of tritiated water (HTO) by Orconectes immunis was investigated under laboratory conditions. Tritium uptake in the tissue-free water fraction (TFWT) was described using an exponential model. When steady-state was reached, the ratio of TFWT to HTO was approximately 0.9. Uptake of tritium in the organically-bound fraction (OBT) proceeded slowly, and had not reached steady-state after 117 days of culture. Although steady-state was never reached, the maximum observed ration of OBT to TFWT in whole animals was approximately 0.6. However, this ratio exceeded unity in the exoskeleton. Specific activity ratios of OBT between crayfish and lettuce (food source) were less than or at unity for various test conditions

Uptake of thallium-201 in enlarged thyroid glands. Concise communication

International Nuclear Information System (INIS)

Fukuchi, M.; Kido, A.; Hyodo, K.; Tachibana, K.; Onoue, K.; Morita, T.; Nagai, K.

1979-01-01

We have investigated the thyroid uptake of Tl-201 in 37 patients with various types of goiter, and in six with normal thyroids. Significant thallium uptake was found in all cases in which there was thyroid enlargement, including Graves' disease, toxic thyroid nodule, primary hypothyroidism, simple goiter, Hashimoto's disease, thyroid carcinoma, and thyroid adenoma. If goiter was absent, however, there was no demonstrable uptake - e.g., in secondary hypothyroidism, subacute thyroiditis, and the normal controls. Thallium uptake did not correlate with thyroid function tests such as BMR, T 3 -RU, T 3 , T 4 , TSH, antithyroid antibodies, or the 24-hr I-131 uptake. In 23 patients with diffuse goiter, on the other hand, maximum Tl-201 uptake correlated well with thyroid weight: r = 0.836 (p < 0.001); y = 0.02 x + 0.06

Airborne Hyperspectral Evaluation of Maximum Gross Photosynthesis, Gravimetric Water Content, and CO2 Uptake Efficiency of the Mer Bleue Ombrotrophic Peatland

Directory of Open Access Journals (Sweden)

J. Pablo Arroyo-Mora

2018-04-01

Full Text Available Peatlands cover a large area in Canada and globally (12% and 3% of the landmass, respectively. These ecosystems play an important role in climate regulation through the sequestration of carbon dioxide from, and the release of methane to, the atmosphere. Monitoring approaches, required to understand the response of peatlands to climate change at large spatial scales, are challenged by their unique vegetation characteristics, intrinsic hydrological complexity, and rapid changes over short periods of time (e.g., seasonality. In this study, we demonstrate the use of multitemporal, high spatial resolution (1 m2 hyperspectral airborne imagery (Compact Airborne Spectrographic Imager (CASI and Shortwave Airborne Spectrographic Imager (SASI sensors for assessing maximum instantaneous gross photosynthesis (PGmax in hummocks, and gravimetric water content (GWC and carbon uptake efficiency in hollows, at the Mer Bleue ombrotrophic bog. We applied empirical models (i.e., in situ data and spectral indices and we derived spatial and temporal trends for the aforementioned variables. Our findings revealed the distribution of hummocks (51.2%, hollows (12.7%, and tree cover (33.6%, which is the first high spatial resolution map of this nature at Mer Bleue. For hummocks, we found growing season PGmax values between 8 μmol m−2 s−1 and 12 μmol m−2 s−1 were predominant (86.3% of the total area. For hollows, our results revealed, for the first time, the spatial heterogeneity and seasonal trends for gravimetric water content and carbon uptake efficiency for the whole bog.

Uptake of thallium-201 in enlarged thyroid glands. Concise communication

Energy Technology Data Exchange (ETDEWEB)

Fukuchi, M.; Kido, A.; Hyodo, K.; Tachibana, K.; Onoue, K.; Morita, T.; Nagai, K.

1979-08-01

We have investigated the thyroid uptake of Tl-201 in 37 patients with various types of goiter, and in six with normal thyroids. Significant thallium uptake was found in all cases in which there was thyroid enlargement, including Graves' disease, toxic thyroid nodule, primary hypothyroidism, simple goiter, Hashimoto's disease, thyroid carcinoma, and thyroid adenoma. If goiter was absent, however, there was no demonstrable uptake - e.g., in secondary hypothyroidism, subacute thyroiditis, and the normal controls. Thallium uptake did not correlate with thyroid function tests such as BMR, T/sub 3/-RU, T/sub 3/, T/sub 4/, TSH, antithyroid antibodies, or the 24-hr I-131 uptake. In 23 patients with diffuse goiter, on the other hand, maximum Tl-201 uptake correlated well with thyroid weight: r = 0.836 (p < 0.001); y = 0.02 x + 0.06.

Evaluation of nitrogen uptake patterns in spring and winter wheat in western Oregon

International Nuclear Information System (INIS)

Baloch, D.M.; Malghani, M.A.K.; Khan, M.A.; Kakar, E.

2010-01-01

An understanding of the ground nitrogen (N) uptake pattern for wheat (Triticum aestivum L.) is essential to facilitate nitrogen management. The purpose of this study was to determine the nitrogen uptake pattern of spring and winter wheat grown in western Oregon, USA. Data used in this study were obtained from three different trials. For spring wheat rotation trials five spring wheat cultivars were used. Fertilizer N (16-16-16-4) at the rate of 140 kg ha/sup -1/ was applied at the time of planting. In small plot rotation trials five fertilizer treatments - 0, 50, 100,150 and 200 kg N ha/sup -1/ were used. Rotations include winter wheat following clover and winter wheat following oat. The N uptake and dry matter yield of winter wheat were also determined from unfertilized plots of wheat trial. The maximum N uptake for spring wheat and winter wheat were at 1100 and 2000 accumulated growing degree days (GDD), before Feekes 10, respectively. The maximum N uptake rate for spring wheat, 0.038 kg N GDD/sup -1/, occurred at 750 GDD and the peak N uptake was observed approximately 35 days after Feekes 2. Nitrogen uptake in winter wheat was significantly affected by rotations. (author)

Characterization of brown adipose tissue 18F-FDG uptake in PET/CT imaging and its influencing factors in the Chinese population

International Nuclear Information System (INIS)

Shao, Xiaonan; Shao, Xiaoliang; Wang, Xiaosong; Wang, Yuetao

2016-01-01

18 F-FDG PET/CT has been widely applied for tumor imaging. However, it is reported that many normal tissues, e.g., brown adipose tissue, can also uptake 18 F-FDG. The purpose of this study was to determine the imaging characteristics of 18 F-FDG uptake in brown adipose tissue (BAT) in PET/CT. A total of 2,944 patients who underwent PET/CT from September 2011 to March 2013 were analyzed retrospectively. Imaging features of 18 F-FDG uptake in BAT were analyzed. Univariate analysis and logistic regression analysis were performed to evaluate the effect of age, gender, cancer status, body mass index (BMI), average daily maximum temperature of imaging month and fasting plasma glucose (Glu) on the positive rate of 18 F-FDG uptake in BAT. The results showed that 1.9% (57/2944) patients had 18 F-FDG uptake in BAT. 18 F-FDG, manifested as flaky, nodular and beaded shape, was symmetrically distributed in the adipose tissues of cervical and supraclavicular, mediastinal, paravertebral, and perirenal areas. Uptake of 18 F-FDG within cervical/supraclavicular area was most common (89.5%, 51/57) with an SUV max ranging from 2.8 to 31.4. Univariate analysis showed that gender and cancer status were not significantly correlated with the BAT 18 F-FDG uptake rate. In contrast, age, BMI, Glu and average daily maximum temperature in the imaging month were significantly correlated with the BAT 18 F-FDG uptake rate (P < 0.05). Further logistic regression analysis showed that only age, BMI and average daily maximum temperature were significant (OR < 1, P < 0.05). Based on the value of OR, the most significant factor that affects BAT 18 F-FDG uptake rate was age, followed by the average daily maximum temperature and BMI. We concluded that Chinese adult has low positive rate of 18 F-FDG uptake in BAT. Cervical/Supraclavicular is the most common area with BAT 18 F-FDG uptake. Age, average daily maximum temperature and BMI are independent factors affecting 18 F-FDG uptake.

Maximum oxygen uptake and objectively measured physical activity in Danish children 6-7 years of age: the Copenhagen school child intervention study

DEFF Research Database (Denmark)

Eiberg, Stig; Hasselstrøm, Henriette; Grønfeldt, Vivian

2005-01-01

Objectives: To provide normative data on maximum oxygen uptake (V·O2MAX) and physical activity in children 6-7 years of age and analyse the association between these variables. Methods: VO2MAX was measured in 366 boys (mean (SD) 6.8 (0.4) years of age) and 332 girls (6.7 (0.4) years of age) from.......5 (6.0) v 44.8 (5.6) ml/kg/min (+8%); pgirls. The difference in VO2MAX between boys and girls decreased to +2% when expressed relative to lean body mass (LBM). Absolute VO2MAX was related to LBM, body mass, and stature (all pBoys were more physically active than girls (mean counts...... +9.4%, pboys and girls with the same VO2MAX were compared, boys were more active. The difference in physical activity between the sexes was higher when sustained activity of higher intensity was compared. Conclusions: VO2MAX is higher in boys than girls (+11%), even when...

Platinum uptake from chloride solutions using biosorbents

Directory of Open Access Journals (Sweden)

Mehmet Hakan Morcali

2013-04-01

Full Text Available Present work investigates platinum uptake from synthetically prepared, dilute platinum-bearing solutions using biomass residues, i.e. pistachio nut shell and rice husk, which are abundant in Turkey, and provides a comparison between these two biosorbents. Effects of the different uptake parameters, sorbent dosage, contact time, temperature and pH of solution on platinum uptake (% were studied in detail on a batch sorption. Before the pistachio nut shell was activated, platinum uptake (% was poor compared to the rice husk. However, after the pistachio nut shell was activated at 1000 °C under an argon atmosphere, the platinum uptake (% increased two-fold. The pistachio nut shell (original and activated and rice husk were shown to be better than commercially available activated carbon in terms of adsorption capacity. These two sorbents have also been characterized by FTIR and SEM. Adsorption equilibrium data best complied with the Langmuir isotherm model. Maximum adsorption capacities, Qmax, at 25 °C were found to be 38.31 and 42.02 mg.g- 1for the activated pistachio nut shell and rice husk, respectively. Thermodynamic calculations using the measured ∆H°, ∆S° and ∆G° values indicate that the uptake process was spontaneous and endothermic. The experimental data were shown to be fit the pseudo-second-order kinetic model.

Maximum Plant Uptakes for Water, Nutrients, and Oxygen Are Not Always Met by Irrigation Rate and Distribution in Water-based Cultivation Systems.

Science.gov (United States)

Blok, Chris; Jackson, Brian E; Guo, Xianfeng; de Visser, Pieter H B; Marcelis, Leo F M

2017-01-01

Growing on rooting media other than soils in situ -i.e., substrate-based growing- allows for higher yields than soil-based growing as transport rates of water, nutrients, and oxygen in substrate surpass those in soil. Possibly water-based growing allows for even higher yields as transport rates of water and nutrients in water surpass those in substrate, even though the transport of oxygen may be more complex. Transport rates can only limit growth when they are below a rate corresponding to maximum plant uptake. Our first objective was to compare Chrysanthemum growth performance for three water-based growing systems with different irrigation. We compared; multi-point irrigation into a pond (DeepFlow); one-point irrigation resulting in a thin film of running water (NutrientFlow) and multi-point irrigation as droplets through air (Aeroponic). Second objective was to compare press pots as propagation medium with nutrient solution as propagation medium. The comparison included DeepFlow water-rooted cuttings with either the stem 1 cm into the nutrient solution or with the stem 1 cm above the nutrient solution. Measurements included fresh weight, dry weight, length, water supply, nutrient supply, and oxygen levels. To account for differences in radiation sum received, crop performance was evaluated with Radiation Use Efficiency (RUE) expressed as dry weight over sum of Photosynthetically Active Radiation. The reference, DeepFlow with substrate-based propagation, showed the highest RUE, even while the oxygen supply provided by irrigation was potentially growth limiting. DeepFlow with water-based propagation showed 15-17% lower RUEs than the reference. NutrientFlow showed 8% lower RUE than the reference, in combination with potentially limiting irrigation supply of nutrients and oxygen. Aeroponic showed RUE levels similar to the reference and Aeroponic had non-limiting irrigation supply of water, nutrients, and oxygen. Water-based propagation affected the subsequent

Controls on seasonal patterns of maximum ecosystem carbon uptake and canopy-scale photosynthetic light response: contributions from both temperature and photoperiod.

Science.gov (United States)

Stoy, Paul C; Trowbridge, Amy M; Bauerle, William L

2014-02-01

Most models of photosynthetic activity assume that temperature is the dominant control over physiological processes. Recent studies have found, however, that photoperiod is a better descriptor than temperature of the seasonal variability of photosynthetic physiology at the leaf scale. Incorporating photoperiodic control into global models consequently improves their representation of the seasonality and magnitude of atmospheric CO2 concentration. The role of photoperiod versus that of temperature in controlling the seasonal variability of photosynthetic function at the canopy scale remains unexplored. We quantified the seasonal variability of ecosystem-level light response curves using nearly 400 site years of eddy covariance data from over eighty Free Fair-Use sites in the FLUXNET database. Model parameters describing maximum canopy CO2 uptake and the initial slope of the light response curve peaked after peak temperature in about 2/3 of site years examined, emphasizing the important role of temperature in controlling seasonal photosynthetic function. Akaike's Information Criterion analyses indicated that photoperiod should be included in models of seasonal parameter variability in over 90% of the site years investigated here, demonstrating that photoperiod also plays an important role in controlling seasonal photosynthetic function. We also performed a Granger causality analysis on both gross ecosystem productivity (GEP) and GEP normalized by photosynthetic photon flux density (GEP n ). While photoperiod Granger-caused GEP and GEP n in 99 and 92% of all site years, respectively, air temperature Granger-caused GEP in a mere 32% of site years but Granger-caused GEP n in 81% of all site years. Results demonstrate that incorporating photoperiod may be a logical step toward improving models of ecosystem carbon uptake, but not at the expense of including enzyme kinetic-based temperature constraints on canopy-scale photosynthesis.

A modified assay method for determining serotonin uptake in human platelets

International Nuclear Information System (INIS)

Arora, R.C.; Meltzer, H.Y.

1981-01-01

Effects of various experimental conditions on serotonin (5-HT) uptake in human platelets were examined. The experimental design allowed the evaluation of the effect of diffusion and other non-saturable processes on the affinity and maximum activity of the membrane pump for 5-HT uptake. Total 5-HT uptake was determined by incubating platelet-rich plasma (PRP) with increasing concentrations of serotonin at 37 0 C for 4 min. The passive uptake was measured by the addition of various 5-HT concentrations to PRP in buffer at 37 0 C, followed by immediate transfer to an ice-cold water bath. The difference between the total and passive uptake was linear for 6 min. The affinity (Ksub(m)) for active platelet serotonin uptake was 0.45 +- 0.09 μmol/l and maximal rate of uptake (V) was 10.7 +- 2.1 pmol/10 7 platelets/min. The described method provides a convenient and reliable measure of active 5-HT uptake suitable for clinical investigation. The effect of passive diffusion on kinetic parameters is discussed. (Auth.)

Differential uptake of salicylate in serum, cerebrospinal fluid, and perilymph.

Science.gov (United States)

Jastreboff, P J; Hansen, R; Sasaki, P G; Sasaki, C T

1986-10-01

After intraperitoneal administration of salicylate in anesthetized rats and guinea pigs, we found that salicylate levels in perilymph (PL) are closely related to both drug levels in cerebrospinal fluid (CSF) and in serum, with higher levels systematically observed in PL than in CSF. Further analysis suggests that salicylate is not passively transported into PL across CSF but, rather, is transported from blood directly to PL. The time course of salicylate uptake in rats reveals maximum levels at 1 1/2 hours (serum) and two to four hours (CSF and PL). On the other hand, salicylate uptake into serum and CSF of guinea pigs exhibits a longer time course, with maximum levels reached at four hours (serum) and five hours (CSF). These data, not previously available, are basic to our understanding of salicylate-related auditory effects.

[3H]Dopamine uptake by platelet storage granules in schizophrenia

International Nuclear Information System (INIS)

Rabey, J.M.; Graff, E.; Oberman, Z.; Lerner, A.; Sigal, M.

1992-01-01

[ 3 H]Dopamine (DA) uptake by platelet storage granules was determined in 26 schizophrenic male patients, paranoid type (14 acute stage; 12 in remission) and 20 age-matched, normal controls. maximum velocity (Vmax) of DA uptake was significantly higher in acute patients, than patients in remission or controls (p>0.05). The apparent Michaelis constant (kM) of DA uptake in acute patients was also significantly different from chronic patients a substantial diminution of DA uptake, while haloperidol produced a substantial diminution of DA uptake, while haloperidol (10 -4 , 10 -5 M) did not affect the assay. Considering that a DA disequilibrium in schizophrenia may be expressed not only in the brain, but also in the periphery and that an increased amount of DA accumulated in the vesicles, implies that an increased quantity of catecholamine is available for release, our findings suggest additional evidence for the role of DA overactivity in the pathophysiology of this disorder

Nitrogen deposition and prey nitrogen uptake control the nutrition of the carnivorous plant Drosera rotundifolia

Energy Technology Data Exchange (ETDEWEB)

Millett, J., E-mail: j.millett@lboro.ac.uk [Centre for Hydrological and Ecosystem Science, Department of Geography, Loughborough University, Loughborough LE11 3TU (United Kingdom); Foot, G.W. [Centre for Hydrological and Ecosystem Science, Department of Geography, Loughborough University, Loughborough LE11 3TU (United Kingdom); Svensson, B.M. [Department of Plant Ecology and Evolution, Uppsala University, Norbyvägen 18 D, SE-752 36 Uppsala (Sweden)

2015-04-15

Nitrogen (N) deposition has important negative impacts on natural and semi-natural ecosystems, impacting on biotic interactions across trophic levels. Low-nutrient systems are particularly sensitive to changes in N inputs and are therefore more vulnerable to N deposition. Carnivorous plants are often part of these ecosystems partly because of the additional nutrients obtained from prey. We studied the impact of N deposition on the nutrition of the carnivorous plant Drosera rotundifolia growing on 16 ombrotrophic bogs across Europe. We measured tissue N, phosphorus (P) and potassium (K) concentrations and prey and root N uptake using a natural abundance stable isotope approach. Our aim was to test the impact of N deposition on D. rotundifolia prey and root N uptake, and nutrient stoichiometry. D. rotundifolia root N uptake was strongly affected by N deposition, possibly resulting in reduced N limitation. The contribution of prey N to the N contained in D. rotundifolia ranged from 20 to 60%. N deposition reduced the maximum amount of N derived from prey, but this varied below this maximum. D. rotundifolia tissue N concentrations were a product of both root N availability and prey N uptake. Increased prey N uptake was correlated with increased tissue P concentrations indicating uptake of P from prey. N deposition therefore reduced the strength of a carnivorous plant–prey interaction, resulting in a reduction in nutrient transfer between trophic levels. We suggest that N deposition has a negative impact on D. rotundifolia and that responses to N deposition might be strongly site specific. - Highlights: • We measured nutrition of the carnivorous plant Drosera rotundifolia across Europe. • We measured tissue nutrient concentrations and prey and root N uptake at 16 sites. • Tissue N concentrations were a product of root N availability and prey N uptake. • N deposition reduced the maximum amount of N derived from prey. • N deposition reduced the strength of a

Nitrogen deposition and prey nitrogen uptake control the nutrition of the carnivorous plant Drosera rotundifolia

International Nuclear Information System (INIS)

Millett, J.; Foot, G.W.; Svensson, B.M.

2015-01-01

Nitrogen (N) deposition has important negative impacts on natural and semi-natural ecosystems, impacting on biotic interactions across trophic levels. Low-nutrient systems are particularly sensitive to changes in N inputs and are therefore more vulnerable to N deposition. Carnivorous plants are often part of these ecosystems partly because of the additional nutrients obtained from prey. We studied the impact of N deposition on the nutrition of the carnivorous plant Drosera rotundifolia growing on 16 ombrotrophic bogs across Europe. We measured tissue N, phosphorus (P) and potassium (K) concentrations and prey and root N uptake using a natural abundance stable isotope approach. Our aim was to test the impact of N deposition on D. rotundifolia prey and root N uptake, and nutrient stoichiometry. D. rotundifolia root N uptake was strongly affected by N deposition, possibly resulting in reduced N limitation. The contribution of prey N to the N contained in D. rotundifolia ranged from 20 to 60%. N deposition reduced the maximum amount of N derived from prey, but this varied below this maximum. D. rotundifolia tissue N concentrations were a product of both root N availability and prey N uptake. Increased prey N uptake was correlated with increased tissue P concentrations indicating uptake of P from prey. N deposition therefore reduced the strength of a carnivorous plant–prey interaction, resulting in a reduction in nutrient transfer between trophic levels. We suggest that N deposition has a negative impact on D. rotundifolia and that responses to N deposition might be strongly site specific. - Highlights: • We measured nutrition of the carnivorous plant Drosera rotundifolia across Europe. • We measured tissue nutrient concentrations and prey and root N uptake at 16 sites. • Tissue N concentrations were a product of root N availability and prey N uptake. • N deposition reduced the maximum amount of N derived from prey. • N deposition reduced the strength of a

The maximum standardized uptake value of 18 F-FDG PET scan to determine prognosis of hormone-receptor positive metastatic breast cancer

International Nuclear Information System (INIS)

Zhang, Jian; Hu, Xi-Chun; Jia, Zhen; Ragaz, Joseph; Zhang, Ying-Jian; Zhou, Min; Zhang, Yong-Ping; Li, Gang; Wang, Bi-Yun; Wang, Zhong-Hua

2013-01-01

Whether PET scan maximum standard uptake value (SUVmax) could differentiate luminal A from luminal B and help predict the survival of metastatic breast cancer (MBC) patients with luminal subtype is still unknown and need to be investigated. 305 MBC patients with luminal subtypes were screened with PET/CT. Eligible patients were prospectively followed up. In total, 134 patients were eligible for this study. SUVmax was significantly related to the number of metastatic sites and presence of visceral metastasis on univariate analysis. SUVmax could not effectively differentiate patients with luminal A from luminal B subtype. Although luminal subtype at diagnosis could predict the relapse-free interval, it could not predict progression-free survival (PFS) or overall survival (OS) after developing relapse. In contrast, SUVmax was predictive of both PFS and OS and this effect was maintained in multivariate COX regression model. SUVmax of MBC did not correlate with molecular subtypes of primary tumor. While molecular subtype may be a valuable prognostic factor at primary diagnosis of breast cancer, the SUVmax, rather than molecular subtype, does have a potential to predict independently in multivariate analysis for the PFS and OS in patients with metastatic disease of luminal subtype

Spatiotemporal variation of nitrate uptake kinetics within the maize (Zea mays L.) root system is associated with greater nitrate uptake and interactions with architectural phenes.

Science.gov (United States)

York, Larry M; Silberbush, Moshe; Lynch, Jonathan P

2016-06-01

Increasing maize nitrogen acquisition efficiency is a major goal for the 21st century. Nitrate uptake kinetics (NUK) are defined by I max and K m, which denote the maximum uptake rate and the affinity of transporters, respectively. Because NUK have been studied predominantly at the molecular and whole-root system levels, little is known about the functional importance of NUK variation within root systems. A novel method was created to measure NUK of root segments that demonstrated variation in NUK among root classes (seminal, lateral, crown, and brace). I max varied among root class, plant age, and nitrate deprivation combinations, but was most affected by plant age, which increased I max, and nitrate deprivation time, which decreased I max K m was greatest for crown roots. The functional-structural simulation SimRoot was used for sensitivity analysis of plant growth to root segment I max and K m, as well as to test interactions of I max with root system architectural phenes. Simulated plant growth was more sensitive to I max than K m, and reached an asymptote near the maximum I max observed in the empirical studies. Increasing the I max of lateral roots had the largest effect on shoot growth. Additive effects of I max and architectural phenes on nitrate uptake were observed. Empirically, only lateral root tips aged 20 d operated at the maximum I max, and simulations demonstrated that increasing all seminal and lateral classes to this maximum rate could increase plant growth by as much as 26%. Therefore, optimizing I max for all maize root classes merits attention as a promising breeding goal. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

( sup 3 H)Dopamine uptake by platelet storage granules in schizophrenia

Energy Technology Data Exchange (ETDEWEB)

Rabey, J.M.; Graff, E.; Oberman, Z. (Tel-Aviv Sourasky Medical Center (Israel)); Lerner, A.; Sigal, M. (Tel-Aviv Univ. (Israel))

1992-01-01

({sup 3}H)Dopamine (DA) uptake by platelet storage granules was determined in 26 schizophrenic male patients, paranoid type (14 acute stage; 12 in remission) and 20 age-matched, normal controls. maximum velocity (Vmax) of DA uptake was significantly higher in acute patients, than patients in remission or controls (p>0.05). The apparent Michaelis constant (kM) of DA uptake in acute patients was also significantly different from chronic patients a substantial diminution of DA uptake, while haloperidol produced a substantial diminution of DA uptake, while haloperidol (10{sup {minus}4}, 10{sup {minus}5} M) did not affect the assay. Considering that a DA disequilibrium in schizophrenia may be expressed not only in the brain, but also in the periphery and that an increased amount of DA accumulated in the vesicles, implies that an increased quantity of catecholamine is available for release, our findings suggest additional evidence for the role of DA overactivity in the pathophysiology of this disorder.

Research on the uptake of mercury 197 acetate in early bronchial cancers and on the variation of this uptake during drug therapy

International Nuclear Information System (INIS)

Gautier, H.M.

1975-01-01

Mercury 197 was proposed as a means to analyze the behavior of early bronchial cancers, especially during drug treatment. This choice was based on four facts: a hyperfixation of mercury has already been demonstrated in malignant intrathoracic tumors; the use of mercury 197 in acetate form gives higher uptake rates than those observed with bichloride; because of its properties mercury 197 is easy to use in routine radioisotopic practice; mercury toxicity is negligible with the preparation employed. The work was performed in two stages: analysis of the uptake conditions for mercury 197 in acetate form in order to detect the factors which influence this uptake and to define its limits and advantages; on the basis of the above notions, use of mercury 197 as tracer to follow the development of bronchial tumors, the aim being to observe the tumor volume variation under drug treatment (the changes in uptake rate are analyzed and the numerical results obtained used to estimate the degree of efficiency of the treatment proposed, the moment of maximum result and the start of a new tumoral growth) [fr

Uptake of uranium from sea water by microalgae

International Nuclear Information System (INIS)

Sakaguchi, Takashi; Horikoshi, Takao; Nakajima, Akira

1978-01-01

The uptake of uranium from aqueous systems especially from sea water by various microalgae was investigated. The freshwater microalgae, Chlorella regularis, Scenedesmus bijuga, Scenedesmus chloreloides, Scenedesmus obliquus, Chlamydomonas angulosa, Chlamydomonas reinhardtii, accumulated relatively large amounts of uranium from the solution containing uranium only. The concentration factors of the above mentioned algae were: Chlorella regularis 3930, Chlamydomonas 2330 - 3400, Scenedesmus 803 - 1920. The uptake of uranium from sea water by Chlorella regularis was inhibited markedly by the co-existence of carbonate ions. Chlorella cells could take up a great quantity of uranium from decarbonated sea water. The uptake of uranium was affected by the pH of sea water, and the amount of uranium absorbed was maximum at pH 5. The experiment was carried out to screen marine microalgae which have the ability to accumulate a large amount of uranium from sea water. The uptake of uranium from sea water by marine microalgae of different species turned out to be in the following decreasing order: Synechococcus > Chlamydomonas >> Chlorella > Dunaliella > Platymonas > Calothrix > Porphyridium. The amount of uranium absorbed differed markedly with different species of marine microalgae. (author)

Uptake of hazardous radionuclides within layered chalcogenide for environmental protection

Energy Technology Data Exchange (ETDEWEB)

Sengupta, Pranesh, E-mail: praneshsengupta@gmail.com [Materials Science Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Dudwadkar, N.L. [Fuel Reprocessing Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Vishwanadh, B. [Materials Science Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Pulhani, V. [Health Physics Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Rao, Rekha [Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Tripathi, S.C. [Fuel Reprocessing Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Dey, G.K. [Materials Science Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India)

2014-02-15

Highlights: • Layered chalcogenide with CdI{sub 2} crystal structure prepared by hydrothermal route. • Exploration of the possibilities for radionuclides’ uptake using layered chalcogenide. • Proposing ‘topotactic ionic substitution’ as major uptake mechanism. -- Abstract: Ensuring environmental protection in and around nuclear facilities is a matter of deep concern. Toward this, layered chalcogenide with CdI{sub 2} crystal structure has been prepared. Structural characterizations of layered chalcogenide suggest ‘topotactic ionic substitution’ as the dominant mechanism behind uptake of different cations within its lattice structure. An equilibration time of 45 min and volume to mass ratio of 30:1 are found to absorb {sup 233}U, {sup 239}Pu, {sup 106}Ru, {sup 85+89}Sr, {sup 137}Cs and {sup 241}Am radionuclides to the maximum extents.

Vertical partitioning of phosphate uptake among picoplankton groups in the low Pi Mediterranean Sea

KAUST Repository

Talarmin, Agathe Anne Gaelle; Van Wambeke, F.; Lebaron, P.; Moutin, T.

2015-01-01

Microbial transformations are key processes in marine phosphorus cycling. In this study, we investigated the contribution of phototrophic and heterotrophic groups to phosphate (Pi) uptake fluxes in the euphotic zone of the low-Pi Mediterranean Sea and estimated Pi uptake kinetic characteristics. Surface soluble reactive phosphorus (SRP) concentrations were in the range of 6-80 nmol Lg'1 across the transect, and the community Pi turnover times, assessed using radiolabeled orthophosphate incubations, were longer in the western basin, where the highest bulk and cellular rates were measured. Using live cell sorting, four vertical profiles of Pi uptake rates were established for heterotrophic prokaryotes (Hprok), phototrophic picoeukaryotes (Pic) and Prochlorococcus (Proc) and Synechococcus (Syn) cyanobacteria. Hprok cells contributed up to 82% of total Pi uptake fluxes in the superficial euphotic zone, through constantly high abundances (2.7-10.2 × 105 cells mLg'1) but variable cellular rates (6.6 ± 9.3 amol P cellg'1 hg'1). Cyanobacteria achieved most of the Pi uptake (up to 62%) around the deep chlorophyll maximum depth, through high abundances (up to 1.4 × 105 Proc cells mLg'1) and high cellular uptake rates (up to 40 and 402 amol P cellg'1 hg'1, respectively for Proc and Syn cells). At saturating concentrations, maximum cellular rates up to 132 amol P cellg'1 hg'1 were measured for Syn at station (St.) C, which was 5 and 60 times higher than Proc and Hprok, respectively. Pi uptake capabilities of the different groups likely contribute to their vertical distribution in the low Pi Mediterranean Sea, possibly along with other energy limitations.

Vertical partitioning of phosphate uptake among picoplankton groups in the low Pi Mediterranean Sea

KAUST Repository

Talarmin, Agathe Anne Gaelle

2015-02-26

Microbial transformations are key processes in marine phosphorus cycling. In this study, we investigated the contribution of phototrophic and heterotrophic groups to phosphate (Pi) uptake fluxes in the euphotic zone of the low-Pi Mediterranean Sea and estimated Pi uptake kinetic characteristics. Surface soluble reactive phosphorus (SRP) concentrations were in the range of 6-80 nmol Lg\\'1 across the transect, and the community Pi turnover times, assessed using radiolabeled orthophosphate incubations, were longer in the western basin, where the highest bulk and cellular rates were measured. Using live cell sorting, four vertical profiles of Pi uptake rates were established for heterotrophic prokaryotes (Hprok), phototrophic picoeukaryotes (Pic) and Prochlorococcus (Proc) and Synechococcus (Syn) cyanobacteria. Hprok cells contributed up to 82% of total Pi uptake fluxes in the superficial euphotic zone, through constantly high abundances (2.7-10.2 × 105 cells mLg\\'1) but variable cellular rates (6.6 ± 9.3 amol P cellg\\'1 hg\\'1). Cyanobacteria achieved most of the Pi uptake (up to 62%) around the deep chlorophyll maximum depth, through high abundances (up to 1.4 × 105 Proc cells mLg\\'1) and high cellular uptake rates (up to 40 and 402 amol P cellg\\'1 hg\\'1, respectively for Proc and Syn cells). At saturating concentrations, maximum cellular rates up to 132 amol P cellg\\'1 hg\\'1 were measured for Syn at station (St.) C, which was 5 and 60 times higher than Proc and Hprok, respectively. Pi uptake capabilities of the different groups likely contribute to their vertical distribution in the low Pi Mediterranean Sea, possibly along with other energy limitations.

Uptake study of some radionuclides by Suez Canal bottom sediment

International Nuclear Information System (INIS)

El-Shinawy, R.M.K.; Abdel Fattah, A.T.; Essa, M.W.A.

1986-01-01

Chemical and physical analyses of Suez Canal bottom sediment at its south entrance (Port Taweffek) were carried out. The sediment was separated into its particle size fractions (clay, silt and sand). The different sediment fractions can be arranged with respect to their sorption capacity as follows: clay, natural sediment, sit and sand. The increase of pH results in small increase in the uptake reaching in some cases a maximum value of pH 6 or 8. More significant increase of uptake is observed when the carrier concentration is increased from 10 -6 to 10 -2 M/L

Seasonal dynamics of 60Co uptake by freshwater algae under natural conditions

International Nuclear Information System (INIS)

Koulikov, N.V.; Trapeznikov, A.V.

1988-08-01

The data presented in the present report show that the values of 60 Co uptake coefficient in freshwater algae under naturel conditions can change 5-6 times depending on seasons, reaching maximum values in summer. Specific activity of the radionuclide in water can be essentially changed depending on the nuclear power plant operation mode. In such a nonequilibrium system it is rather questionable to use the uptake coefficient as a constant parameter for the determination of the radionuclide specific activity in water [fr

Use of gamma probe in 131I thyroid uptake studies

International Nuclear Information System (INIS)

Sarmento, Andrea Gondim Leitao

2002-11-01

Evaluation of thyroid uptake by administration of radioactive iodine is a well-defined procedure to assess patient thyroid function. In general, nuclear medicine institutions use gamma cameras coupled to pinhole collimators to perform uptake studies. With the growing use of intraoperative gamma probes in the radioguided surgical techniques, several institutions are purchasing this new and portable equipment, which can technically be also employed to assess patient's thyroid function, permitting further other applications of gamma cameras. The aim of the study was to compare thyroid uptake trails carried out with both gamma camera and intraoperative gamma probe, in order to evaluate the possible use of gamma probe for this purpose. At first a preliminary study of feasibility was carried out using a neck phantom to verify equipment efficiency with known activities of 131 I. Henceforth, work data from 12 patients undergone studies of thyroid uptakes were evaluated, 24 hours after oral administration of 370 kBq of 131 I. The maximum difference observed between the values obtained with both equipment was 60%, which demonstrated the feasibility of the proposed protocol and made clear that gamma probe can be useful for thyroid uptake studies. (author)

Silver Uptake and Reuse of Biomass by Saccharomyces cerevisiae ...

African Journals Online (AJOL)

Studies were carried out on the recovery of bound silver and reuse of Chlorella emersonii and Saccharomyces cerevisiae biomass for further silver uptake after they were placed in contact with 20mg/l silver for 30 minutes to allow for maximum binding. It was found that 0.16M nitric acid gave the best recovery rates of silver.

Characterization of cesium uptake mediated by a potassium transport system of bacteria in a soil conditioner

International Nuclear Information System (INIS)

Zhang, Pengyao; Idota, Yoko; Yano, Kentaro; Negishi, Masayuki; Kawabata, Hideaki; Arakawa, Hiroshi; Ogihara, Takuo; Morimoto, Kaori; Tsuji, Akira

2014-01-01

We found that bacteria in a commercial soil conditioner sold in Ishinomaki, Miyagi, exhibited concentrative and saturable cesium ion (Cs + ) uptake in the natural range of pH and temperature. The concentration of intracellular Cs + could be condensed at least a few times higher compared with the outside medium of the cells. This uptake appeared to be mediated by a K + transport system, since Cs + uptake was dose-dependently inhibited by potassium ion (K + ). Eadie-Hofstee plot analysis indicated that the Cs + uptake involved a single saturable process. The maximum uptake amount (J max ) was the same in the presence and absence of K + , suggesting that Cs + and K + uptakes were competitive with respect to each other. These bacteria might be useful for bioremediation of cesium-contaminated soil. (author)

Uptake studies with chondrotropic 99mTc-chondroitin sulfate in articular cartilage. Implications for imaging osteoarthritis in the knee

International Nuclear Information System (INIS)

Sobal, Grazyna; Dorotka, Ronald; Menzel, Johannes; Sinzinger, Helmut

2013-01-01

Chondroitin sulfate (CS) is an endogenous component of extracellular matrix in the cartilage and can be valuable for imaging of cartilage degeneration after radiolabeling. Data monitoring the uptake of 99m TcCS by human cartilage are rare. Radiolabeling was performed by 99m TcO 4 − /tin method at pH 5.0 in 0.5 M sodium acetate. For uptake studies human articular cartilage (n = 4, 65–79a) derived from individuals undergoing knee replacement (pieces of 3–5 mg wet weight), or frozen tissue sections (5 μ) for autoradiography (10 μCi) were used. The uptake was monitored from 10 min up to 96 h to achieve saturation. As the commercially available drug Condrosulf (IBSA, Lugano) contains Mg-stearate (0.25%) as additive (to improve its gastrointestinal resorption), we investigated the uptake ± additive. The washout of the tracer was examined by tissue incubation after uptake experiments (3 h and 24 h) with PBS-buffer for 10 min to 3 h. Using human articular cartilage the maximal uptake of 99m TcCS (specific activity of 4.1–6.1 Ci/mmol) was continuously increasing with time amounting to a maximum of 53.2% ± 3.2% with additive, versus 39.4% ± 2.3%, without additive, at saturation. Additive increased the resorption of the drug and consecutively its uptake. The washout of the tracer from cartilage after 3 h uptake amounted to 1.5% ± 0.2% with additive, versus 2.6% ± 0.5%, without. After 24 h washout was lower amounting to 1.1% ± 0.1% versus 1.75% ± 0.15%, respectively. Autoradiography revealed also a continuous increase in uptake of 99m TcCS with time. After 10 min of incubation the uptake increase was proportional to the incubation time, reaching the maximum at 48–72 h. Enhanced uptake at the surface (superficial zone) as compared to the subchondral part (deep zone) of slices, was observed. The non-specific uptake in the presence of 50-fold excess of cold CS was time-dependent up to a maximum of 15% (tissue) and 10% (autoradiography), at saturation. The

Land use/land cover and scale influences on in-stream nitrogen uptake kinetics

Science.gov (United States)

Covino, Tim; McGlynn, Brian; McNamara, Rebecca

2012-06-01

Land use/land cover change often leads to increased nutrient loading to streams; however, its influence on stream ecosystem nutrient transport remains poorly understood. Given the deleterious impacts elevated nutrient loading can have on aquatic ecosystems, it is imperative to improve understanding of nutrient retention capacities across stream scales and watershed development gradients. We performed 17 nutrient addition experiments on six streams across the West Fork Gallatin Watershed, Montana, USA, to quantify nitrogen uptake kinetics and retention dynamics across stream sizes (first to fourth order) and along a watershed development gradient. We observed that stream nitrogen (N) uptake kinetics and spiraling parameters varied across streams of different development intensity and scale. In more developed watersheds we observed a fertilization affect. This fertilization affect was evident as increased ash-free dry mass, chlorophylla, and ambient and maximum uptake rates in developed as compared to undeveloped streams. Ash-free dry mass, chlorophylla, and the number of structures in a subwatershed were significantly correlated to nutrient spiraling and kinetic parameters, while ambient and average annual N concentrations were not. Additionally, increased maximum uptake capacities in developed streams contributed to low in-stream nutrient concentrations during the growing season, and helped maintain watershed export at low levels during base flow. Our results indicate that land use/land cover change can enhance in-stream uptake of limiting nutrients and highlight the need for improved understanding of the watershed dynamics that control nutrient export across scales and development intensities for mitigation and protection of aquatic ecosystems.

High and typical 18F-FDG bowel uptake in patients treated with metformin

International Nuclear Information System (INIS)

Gontier, Eric; Bonardel, Gerald; Mantzarides, Marina; Foehrenbach, Herve; Fourme, Emmanuelle; Wartski, Myriam; Pecking, Alain-Paul; Alberini, Jean-Louis; Blondet, Cyrille; Le Stanc, Elise

2008-01-01

This prospective and bi-centric study was conducted in order to determine the impact of antidiabetic treatments (AD) on 18 F-FDG bowel uptake in type 2 diabetic patients. Fifty-five patients with previously diagnosed and treated type 2 diabetes mellitus (group 1) were divided in two subgroups: AD treatment including metformin (n=32; group 1a) and AD treatment excluding metformin (n=23; group 1b). The 95 patients without diabetes mellitus made up controls (group 2). 18 F-FDG uptake in small intestine and colon was visually graded and semi-quantitatively measured using the maximum standardized uptake value. 18 F-FDG bowel uptake was significantly increased in AD patients (group 1) as compared to controls (group 2) (p 18 F-FDG uptake in colon and, to a lesser extent, in small intestine. It raises the question of stopping metformin treatment before an 18 F-FDG PET/CT scan is performed for intra-abdominal neoplasic lesion assessment. (orig.)

Exploring the cell uptake mechanism of phospholipid and polyethylene glycol coated gold nanoparticles

International Nuclear Information System (INIS)

Hao Yuzhi; Chen Jie; Yang Xiaoyang; Huang Min; He Chuan; Song, Steven; Cui Mingyang

2012-01-01

Recently, there has been a lot of interest in using gold nanoparticles (GNPs) for biomedical applications due to their biocompatibility. To increase GNP cell uptake and circulation half-life, and to improve its bio-distribution in vivo, we chose to coat GNPs with 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-(1′-rac-glycerol) (sodium salt) (POPG) and polyethylene glycol (PEG). Two different methods were used to synthesize POPG-GNPs or PEG-GNPs, but the resulting nanoparticle sizes and morphologies were similar. Under the same incubation conditions, POPG-GNPs can be uptaken quicker than PEG-GNPs by cells—specifically, the maximum uptake was 8 h versus 16 h after incubation. In addition, the uptake amount of POPG-GNPs was more than that of PEG-GNPs. The uptake processes were confirmed by SEM and TEM images. The main reason for the greater uptake of POPG-GNPs can be attributed to the structural similarities between the POPG coating and the cell membrane as well as GNP aggregation. (paper)

The Maximum standardized uptake value is more reliable than size measurement in early follow-up to evaluate potential pulmonary malignancies following radiofrequency ablation.

Science.gov (United States)

Alafate, Aierken; Shinya, Takayoshi; Okumura, Yoshihiro; Sato, Shuhei; Hiraki, Takao; Ishii, Hiroaki; Gobara, Hideo; Kato, Katsuya; Fujiwara, Toshiyoshi; Miyoshi, Shinichiro; Kaji, Mitsumasa; Kanazawa, Susumu

2013-01-01

We retrospectively evaluated the accumulation of fluorodeoxy glucose (FDG) in pulmonary malignancies without local recurrence during 2-year follow-up on positron emission tomography (PET)/computed tomography (CT) after radiofrequency ablation (RFA). Thirty tumors in 25 patients were studied (10 non-small cell lung cancers;20 pulmonary metastatic tumors). PET/CT was performed before RFA, 3 months after RFA, and 6 months after RFA. We assessed the FDG accumulation with the maximum standardized uptake value (SUVmax) compared with the diameters of the lesions. The SUVmax had a decreasing tendency in the first 6 months and, at 6 months post-ablation, FDG accumulation was less affected by inflammatory changes than at 3 months post-RFA. The diameter of the ablated lesion exceeded that of the initial tumor at 3 months post-RFA and shrank to pre-ablation dimensions by 6 months post-RFA. SUVmax was more reliable than the size measurements by CT in the first 6 months after RFA, and PET/CT at 6 months post-RFA may be more appropriate for the assessment of FDG accumulation than that at 3 months post-RFA.

The maximum standardized uptake value of 18 F-FDG PET scan to determine prognosis of hormone-receptor positive metastatic breast cancer

Directory of Open Access Journals (Sweden)

Zhang Jian

2013-01-01

Full Text Available Abstract Background Whether PET scan maximum standard uptake value (SUVmax could differentiate luminal A from luminal B and help predict the survival of metastatic breast cancer (MBC patients with luminal subtype is still unknown and need to be investigated. Methods 305 MBC patients with luminal subtypes were screened with PET/CT. Eligible patients were prospectively followed up. Results In total, 134 patients were eligible for this study. SUVmax was significantly related to the number of metastatic sites and presence of visceral metastasis on univariate analysis. SUVmax could not effectively differentiate patients with luminal A from luminal B subtype. Although luminal subtype at diagnosis could predict the relapse-free interval, it could not predict progression-free survival (PFS or overall survival (OS after developing relapse. In contrast, SUVmax was predictive of both PFS and OS and this effect was maintained in multivariate COX regression model. Conclusions SUVmax of MBC did not correlate with molecular subtypes of primary tumor. While molecular subtype may be a valuable prognostic factor at primary diagnosis of breast cancer, the SUVmax, rather than molecular subtype, does have a potential to predict independently in multivariate analysis for the PFS and OS in patients with metastatic disease of luminal subtype.

Uptake of acidic and basic sugar derivatives in Lemna gibba G1

International Nuclear Information System (INIS)

Sanz, A.; Ullrich, C.I.

1989-01-01

The uptake of acidic and basic sugar derivatives in Lemna gibba L. was studied. Uronic acids applied to the experimental solution induced a small decrease of the membrane potential. After incubation of the plants in a 0.1 millimolar solution of these substrates, no decrease in the concentration of reducing groups in the external solution was detected. Respiration increased by 31% with 50 millimolar galacturonic acid, whereas no effect was found with the same concentration of glucuronic acid. Glucosamine caused a considerable concentration-dependent membrane depolarization. ( 14 C)glucosamine uptake followed Michaelis-Menten kinetics together with a linear component. Influx of this substrate was inhibited by glucose but the type of competition could not be clearly distinguished. Glucosamine, 50 millimolar, inhibited the respiration rate by 30%. The glucosamine uptake was pH-dependent, with maximum uptake at around pH 7. Lack of enhancement of uptake by low pH as well as the permanent membrane depolarization suggest a uniport mechanism for the charged species of the substrate and an electroneutral diffusion of the uncharged species

Hydroponic Uptake of Atrazine and Lambda-cyhalothrin in Aquatic Macrophytes

Science.gov (United States)

Bouldin, J. L.; Farris, J. L.; Moore, M. T.; Smith, S.; Cooper, C. M.

2005-05-01

Phytoremediation encompasses an array of plant-associated processes known to mitigate contaminants from soil, sediment, and water. Modification of pesticides associated with agricultural runoff includes processes directly associated with aquatic macrophytes in addition to soil geochemical modifications and associated rhizospheric degradation. Remediation attributes of two vegetative species common to agricultural drainages in the Mississippi Delta, USA, were assessed using atrazine and lambda-cyhalothrin. Concentrations used in 8-d hydroponic exposures were calculated using recommended field applications and a 5% runoff model from a 0.65-cm rainfall event on a 2.02-ha field. While greater atrazine uptake was measured in Juncus effusus, greater lambda-cyhalothrin uptake occurred in Ludwigia peploides. Maximum pesticide uptake was reached within 48 h for each exposure and subsequent translocation of pesticides to upper plant biomass occurred in macrophytes exposed to atrazine. Sequestration of 98.2% of lambda-cyhalothrin in roots of L. peploides was measured after 8 d. Translocation of lambda-cyhalothrin in J. effusus resulted in 25.4% of pesticide uptake partitioned to upper plant biomass. These individual macrophyte remediation studies measured species- and pesticide-specific uptake rates, indicating that the seasonality of pesticide applications and macrophyte emergence might interact strongly to enhance mitigation capabilities in edge-of-field conveyance structures.

Hepatic FDG Uptake is not associated with hepatic steatosis but with visceral fat volume in cancer screening

International Nuclear Information System (INIS)

Pak, Kyoung June; Kim, Seong Jang; Kim, In Joo; Kin, Keun Young; Kim, Hee Young; Kim, So Jung

2012-01-01

We aimed to evaluate the relation between visceral fat volume and fluorodeoxyglucose (FDG)uptake of the liver measured by maximum or mean standardized uptake value. We retrospectively analyzed 96 consecutive records of positron emission tomography/computed tomography (PET/CT)performed for cancer screening between May 2011 and December 2011. Subjects were divided into 2 groups according to Hounsfield unit (HU)of the liver comparing with that of the spleen. The control group (20 women, 56 men)demonstrating HU of the liver equal or greater than that of the spleen included 76 patients, while the fatty liver group (2 Women, 18 men)showing HU of the liver less than that of the spleen included 20 patients. We compared FDG uptake of the liver and visceral fat volume between two groups. We evaluated correlation of hepatic FDG uptake measured by maximum or mean standardized uptake value (SUV)with visceral fat volume and attenuation. The fatty liver disease group showed higher aspartate aminotransferase (AST)of (24.42±7.22, p=0.012), alanine aminotransferase (ALT)of (25.16±11.68, p=0.011), body mass index (BMI)of (24.58±3.29, p=0.021), and visceral fat volume (3063.53±1561.42, p=0.011)than the control group. There were no statistically significant differences of mean standardized uptake value of the liver (liver SUV mean )(2.73±0.19, p=0.723), maximum standardized uptake value of the liver (liver SUV max )(3.39±0.53, p=0.8248)and liver SUV mean /spleen SUV mean (1.13±0.10, p=0.081)between the two groups. Strong correlations were shown between liver SUV mean and BMI (r=0.609, p mean and visceral fat volume (r=0.457, p max was also strongly correlated with BMI (r=0.622, p=0.001)and visceral fat volume (r=0.547, p mean )with liver SUV mean (r=0.003, p=0.979)or liver SUV max (r=-0.120, p=0.244). Hepatic FDG uptake quantified as SUV mean of SUV max is not correlated with hepatic steatosis but with visceral fat volume in cancer screening

The development from kinetic coefficients of a predictive model for the growth of Eichhomia crassipes in the field. I. Generating kinetic coefficients for the model in greenhouse culture

Directory of Open Access Journals (Sweden)

C. F. Musil

1984-12-01

Full Text Available The kinetics of N- and P- limited growth of Eichhornia crassipes (Mart . Solms were investigated in greenhouse culture with the object of developing a model for predicting population sizes, yields, growth rates and frequencies and amounts of harvest, under varying conditions of nutrient loading and climate, to control both nutrient inputs and excessive growth in eutrophied aquatic systems. The kinetic coefficients, maximum specific growth rate (Umax, half saturation coefficient (Ks and yield coefficient (Yc were measured under N and P limitation in replicated batch culture experiments. Umax values and Ks concentrations derived under N limitation ranged from 5,37 to 8,86% d + and from 400 to 1 506 µg  N ℓ1respectively. Those derived under P limitation ranged from 4,51 to 10,89% d 1 and from 41 to 162 fig P ℓ1 respectively. Yc values (fresh mass basis determined ranged from 1 660 to 1 981 (87 to 98 dry mass basis for N and from 16 431 to 18 671 (867 to 980 dry mass basis for P. The reciprocals of Yc values (dry mass basis, expressed as percentages, adequately estimated the minimum limiting concentrations of N and P {% dry mass in the plant tissues. Kinetic coefficients determined are compared with those reported for algae. The experimental method used and results obtained are critically assessed.

The effect of the rate and method of nitrogen application on nitrogen uptake and utilization by broccoli (Brassica oleracea var. italica)

NARCIS (Netherlands)

Everaarts, A.P.; Willigen, de P.

1999-01-01

The effect of the rate and method of nitrogen application on nitrogen uptake and utilization by broccoli (Brassica oleracea var. italica) was studied in four field experiments. The methods of application were broadcast application vs band placement and split application. Maximum uptake of nitrogen

Foliar water uptake of Tamarix ramosissima from an atmosphere of high humidity.

Science.gov (United States)

Li, Shuang; Xiao, Hong-lang; Zhao, Liang; Zhou, Mao-Xian; Wang, Fang

2014-01-01

Many species have been found to be capable of foliar water uptake, but little research has focused on this in desert plants. Tamarix ramosissima was investigated to determine whether its leaves can directly absorb water from high humidity atmosphere and, if they can, to understand the magnitude and importance of foliar water uptake. Various techniques were adopted to demonstrate foliar water uptake under submergence or high atmospheric humidity. The mean increase in leaf water content after submergence was 29.38% and 20.93% for mature and tender leaves, respectively. In the chamber experiment, obvious reverse sap flow occurred when relative humidity (RH) was persistently above 90%. Reverse flow was recorded first in twigs, then in branches and stems. For the stem, the percentage of negative sap flow rate accounting for the maximum value of sap flow reached 10.71%, and its amount accounted for 7.54% of diurnal sap flow. Small rainfall can not only compensate water loss of plant by foliar uptake, but also suppress transpiration. Foliar uptake can appear in the daytime under certain rainfall events. High atmospheric humidity is beneficial for enhancing the water status of plants. Foliar uptake should be an important strategy of water acquisition for desert plants.

Foliar Water Uptake of Tamarix ramosissima from an Atmosphere of High Humidity

Directory of Open Access Journals (Sweden)

Shuang Li

2014-01-01

Full Text Available Many species have been found to be capable of foliar water uptake, but little research has focused on this in desert plants. Tamarix ramosissima was investigated to determine whether its leaves can directly absorb water from high humidity atmosphere and, if they can, to understand the magnitude and importance of foliar water uptake. Various techniques were adopted to demonstrate foliar water uptake under submergence or high atmospheric humidity. The mean increase in leaf water content after submergence was 29.38% and 20.93% for mature and tender leaves, respectively. In the chamber experiment, obvious reverse sap flow occurred when relative humidity (RH was persistently above 90%. Reverse flow was recorded first in twigs, then in branches and stems. For the stem, the percentage of negative sap flow rate accounting for the maximum value of sap flow reached 10.71%, and its amount accounted for 7.54% of diurnal sap flow. Small rainfall can not only compensate water loss of plant by foliar uptake, but also suppress transpiration. Foliar uptake can appear in the daytime under certain rainfall events. High atmospheric humidity is beneficial for enhancing the water status of plants. Foliar uptake should be an important strategy of water acquisition for desert plants.

Lower maximum standardized uptake value of fluorine-18 fluorodeoxyglucose positron emission tomography coupled with computed tomography imaging in pancreatic ductal adenocarcinoma patients with diabetes.

Science.gov (United States)

Chung, Kwang Hyun; Park, Joo Kyung; Lee, Sang Hyub; Hwang, Dae Wook; Cho, Jai Young; Yoon, Yoo-Seok; Han, Ho-Seong; Hwang, Jin-Hyeok

2015-04-01

The effects of diabetes mellitus (DM) on sensitivity of fluorine-18 fluorodeoxyglucose positron emission tomography coupled with computed tomography ((18)F-FDG PET/CT) for diagnosing pancreatic ductal adenocarcinomas (PDACs) is not well known. This study was aimed to evaluate the effects of DM on the validity of (18)F-FDG PET/CT in PDAC. A total of 173 patients with PDACs who underwent (18)F-FDG PET/CT were enrolled (75 in the DM group and 98 in the non-DM group). The maximum standardized uptake values (SUVsmax) were compared. The mean SUVmax was significantly lower in the DM group than in the non-DM group (4.403 vs 5.998, P = .001). The sensitivity of SUVmax (cut-off value 4.0) was significantly lower in the DM group than in the non-DM group (49.3% vs 75.5%, P < .001) and also lower in normoglycemic DM patients (n = 24) than in non-DM patients (54.2% vs 75.5%, P = .038). DM contributes to a lower SUVmax of (18)F-FDG PET/CT in patients with PDACs. Copyright © 2015 Elsevier Inc. All rights reserved.

Normal patterns of 18F-FDG appendiceal uptake in children

Energy Technology Data Exchange (ETDEWEB)

Reavey, Hamilton E. [Emory University, Department of Radiology and Imaging Sciences, Division of Nuclear Medicine Molecular Imaging, Atlanta, GA (United States); Alazraki, Adina L.; Simoneaux, Stephen F. [Emory University, Department of Radiology and Imaging Sciences, Division of Pediatric Imaging, Children' s Healthcare of Atlanta at Egleston, Atlanta, GA (United States)

2014-04-15

Prior to interpreting PET/CT, it is crucial to understand the normal biodistribution of fluorodeoxyglucose (FDG). It is also important to realize that the normal biodistribution can vary between adults and children. Although many studies have defined normal patterns of pediatric FDG uptake in structures like the thymus, brown fat and bone marrow, patterns of normal pediatric bowel activity, specifically uptake within the appendix, have not been well described. Active lymphoid tissue has increased FDG uptake when compared with inactive tissue. Since children have more active lymphoid tissue than adults, and because the appendix contains aggregated lymphoid tissue, we postulated that appendiceal uptake may be increased in pediatric patients. To define the normal level of appendiceal FDG activity in children by evaluating a series of consecutive FDG PET/CT scans performed for other indications. After obtaining IRB approval, we retrospectively reviewed 128 consecutive whole-body pediatric FDG PET/CT examinations obtained for a variety of clinical indications. CT scans on which the appendix could not be visualized were excluded from analysis. CT scans on which the appendix could be visualized were evaluated for underlying appendiceal pathology. Studies with appendiceal or periappendiceal pathology by CT criteria were excluded. A region of interest (ROI) was placed over a portion of each appendix and appendiceal maximum standardized uptake value (SUVmax) was calculated. If an adjacent loop of bowel activity interfered with accurate measurements of the appendix SUVmax, the scan was excluded from the analysis. A chart review was performed on patients with elevated appendiceal SUVmax values to ensure that the patients did not have clinical symptomatology suggestive of acute appendicitis. When the appendix or a portion of the appendix could be visualized and accurately measured, the SUVmax was determined. SUVmax of the appendix was compared to the SUVmax of normal liver and

Hepatic FDG Uptake is not associated with hepatic steatosis but with visceral fat volume in cancer screening

Energy Technology Data Exchange (ETDEWEB)

Pak, Kyoung June; Kim, Seong Jang; Kim, In Joo; Kin, Keun Young; Kim, Hee Young; Kim, So Jung [Pusan National Univ. Hospital, Busan (Korea, Republic of)

2012-09-15

We aimed to evaluate the relation between visceral fat volume and fluorodeoxyglucose (FDG)uptake of the liver measured by maximum or mean standardized uptake value. We retrospectively analyzed 96 consecutive records of positron emission tomography/computed tomography (PET/CT)performed for cancer screening between May 2011 and December 2011. Subjects were divided into 2 groups according to Hounsfield unit (HU)of the liver comparing with that of the spleen. The control group (20 women, 56 men)demonstrating HU of the liver equal or greater than that of the spleen included 76 patients, while the fatty liver group (2 Women, 18 men)showing HU of the liver less than that of the spleen included 20 patients. We compared FDG uptake of the liver and visceral fat volume between two groups. We evaluated correlation of hepatic FDG uptake measured by maximum or mean standardized uptake value (SUV)with visceral fat volume and attenuation. The fatty liver disease group showed higher aspartate aminotransferase (AST)of (24.42{+-}7.22, p=0.012), alanine aminotransferase (ALT)of (25.16{+-}11.68, p=0.011), body mass index (BMI)of (24.58{+-}3.29, p=0.021), and visceral fat volume (3063.53{+-}1561.42, p=0.011)than the control group. There were no statistically significant differences of mean standardized uptake value of the liver (liver SUV{sup mean})(2.73{+-}0.19, p=0.723), maximum standardized uptake value of the liver (liver SUV{sup max})(3.39{+-}0.53, p=0.8248)and liver SUV{sup mean}/spleen SUV{sup mean}(1.13{+-}0.10, p=0.081)between the two groups. Strong correlations were shown between liver SUV{sup mean} and BMI (r=0.609, p<0.001)and between liver SUV{sup mean} and visceral fat volume (r=0.457, p<0.001). Liver SUV{sup max} was also strongly correlated with BMI (r=0.622, p=0.001)and visceral fat volume (r=0.547, p<0.001). There was no significant association of mean attenuation value of the liver (liver HU{sup mean})with liver SUV{sup mean} (r=0.003, p=0.979)or liver SUV{sup max} (r

Prognostic value of tumor-to-blood standardized uptake ratio in patients with resectable non-small-cell lung cancer

Energy Technology Data Exchange (ETDEWEB)

Shin, Seung Hyeon; Pak, Kyoung June; Kim, In Joo [Dept. of Nuclear Medicine and Biomedical Research Institute, Pusan National University Hospital, Busan(Korea, Republic of); Kim, Bum Soo; Kim, Seong Jang [Dept. of Nuclear Medicine and Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan (Korea, Republic of)

2017-09-15

Previously published studies showed that the standard tumor-to-blood standardized uptake value (SUV) ratio (SUR) was a more accurate prognostic method than tumor maximum standardized uptake value (SUVmax). This study evaluated and compared prognostic value of positron emission tomography (PET) parameters and normalized value of PET parameters by blood pool SUV in non-small-cell lung cancer (NSCLC) patients who received curative surgery.

Prognostic value of tumor-to-blood standardized uptake ratio in patients with resectable non-small-cell lung cancer

International Nuclear Information System (INIS)

Shin, Seung Hyeon; Pak, Kyoung June; Kim, In Joo; Kim, Bum Soo; Kim, Seong Jang

2017-01-01

Previously published studies showed that the standard tumor-to-blood standardized uptake value (SUV) ratio (SUR) was a more accurate prognostic method than tumor maximum standardized uptake value (SUVmax). This study evaluated and compared prognostic value of positron emission tomography (PET) parameters and normalized value of PET parameters by blood pool SUV in non-small-cell lung cancer (NSCLC) patients who received curative surgery

Uptake and loss of Cesium - 134 by the snail Biomphalaria glabrata (Say, 1818)

International Nuclear Information System (INIS)

Kikuchi, O.K.; Mastro, N.L. del.

1988-07-01

The uptake and loss of Cs-134 produced in IEA-R1 reactor of IPEN was observed in fresh water adult snails. Two activites were employed: 3.700 and 18.500 Bq/1. A monochannel analyses was used for radiactivity couting and the number of egg-laying and embryo were registered. Maximum uptake occured approximately at 8 th day and the biological half-life was about 6 days. Although the egg-laying and embryo number were diminished with Cs-134 presence, it is not possible to affirm that result due to the small number of animals used. (author) [pt

Hepatic steatosis is associated with increased hepatic FDG uptake

Energy Technology Data Exchange (ETDEWEB)

Keramida, Georgia, E-mail: G.Keramida@bsms.ac.uk [Clinical Imaging Sciences Centre, Brighton Sussex Medical School, Brighton (United Kingdom); Department of Nuclear Medicine, Brighton Sussex University Hospitals NHS Trust, Brighton (United Kingdom); Potts, Jon [Department of Medicine, Brighton Sussex University Hospitals NHS Trust, Brighton (United Kingdom); Bush, Janice [Clinical Imaging Sciences Centre, Brighton Sussex Medical School, Brighton (United Kingdom); Dizdarevic, Sabina; Peters, A. Michael [Clinical Imaging Sciences Centre, Brighton Sussex Medical School, Brighton (United Kingdom); Department of Nuclear Medicine, Brighton Sussex University Hospitals NHS Trust, Brighton (United Kingdom)

2014-05-15

Objective: The use of liver as a reference tissue for semi-quantification of tumour FDG uptake may not be valid in hepatic steatosis (HS). Previous studies on the relation between liver FDG uptake and HS have been contradictory probably because they ignored blood glucose (BG). Because hepatocyte and blood FDG concentrations equalize, liver FDG uptake parallels BG, which must therefore be considered when studying hepatic FDG uptake. We therefore re-examined the relation between HS and liver uptake taking BG into account. Methods: This was a retrospective study of 304 patients undergoing routine PET/CT with imaging 60 min post-FDG. Average standard uptake value (SUV{sub ave}), maximum SUV (SUV{sub max}) and CT density (index of HS) were measured in a liver ROI. Blood pool SUV was based on the left ventricular cavity (SUV{sub LV}). Correlations were assessed using least squares fitting of continuous data. Patients were also divided into BG subgroups (<4, 4–5, 5–6, 6–8, 8–10 and 10+ mmol/l). Results: SUV{sub ave}, SUV{sub max} and SUV{sub LV} displayed similar relations with BG. SUV{sub max}/SUV{sub LV}, but not SUV{sub ave}/SUV{sub LV}, correlated significantly with BG. SUV{sub max}, but not SUV{sub ave}, correlated inversely with CT density before and after adjusting for BG. SUV{sub max}/SUV{sub ave} correlated more strongly with CT density than SUV{sub max}. CT density correlated inversely with SUV{sub max}/SUV{sub LV} but positively with SUV{sub ave}/SUV{sub LV}. Conclusions: Hepatic SUV is more influenced by BG than by HS. Its relation with BG renders it unsuitable as a reference tissue. Nevertheless, hepatic fat does correlate positively with liver SUV, although this is seen only with SUV{sub max} because SUV{sub ave} is ‘diluted’ by hepatic fat.

Incidental thyroid uptake on F-18 FDG PET/CT. Correlation with ultrasonography and pathology

International Nuclear Information System (INIS)

Kang, Bong-Joo; Baik, Jun-Hyun; Jung, So-Lyung; Park, Young-Ha; O, Joo-Hyun; Chung, Soo-Kyo

2009-01-01

The purpose of this study was to evaluate the usefulness of maximum standard uptake value (max SUV) calculated from F-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) examination and findings from ultrasonographic (US) examination on incidentally detected thyroid FDG uptake on FDG PET/CT. We collected and reviewed FDG PET/CT images performed at our institution from March 2005 to March 2008. This study included 190 subjects with increased FDG uptake of thyroid gland who later underwent thyroid US and histological examinations. Of these subjects, the uptake pattern on FDG PET/CT was classified as either diffuse or focal. The FDG uptake pattern, max SUV, and US findings were evaluated and correlated with the histological results. In the focal FDG uptake pattern cases (n=148), the mean max SUV of malignant cases was higher than that of benign cases (5.93±5.35 vs. 3.47±2.89). Of the diffuse FDG uptake cases (n=42), nodules were detected in 25 subjects (59.5%) by US examination. Thyroid nodules were well characterized on US studies, and combined findings of suspicious US features or high max SUV of focal FDG uptake lesion increased sensitivity, positive predictive value (PPV), negative predictive value (NPV), and accuracy. Focal uptake pattern and high max SUV may be helpful in differentiating benign and malignant nodules on FDG PET/CT. However, US examination provides further information, and for lesions with increased FDG uptake of thyroid, US examination should be recommended. (author)

Interaction effect on nitrogen and sulfur on growth and nutrient uptake by maize

International Nuclear Information System (INIS)

Jaggi, R.C.; Aulakh, M.S.; Dev, G.

1977-01-01

A pot culture experiment was conducted in the greenhouse on an arid brown loamy sand deficient in both available N and S with maize (Ganga-5) as the test corp. Three levels of N (0, 30, 60 ppm) as NH 4 Cl in factorial combination with three levels of S (0, 10, 20 ppm) as Na 2 35 SO 4 were replicated thrice. Application of N upto 60 ppm S significantly increased dry matter yield and uptake of N and S by maize (stem + levels) and their combined application showed sinergistic effect for both yield and uptake of these nutrients. Maximum yield of dry matter and uptake of the nutrients were obtained with the application of 60 ppm N and 20 ppm S. The radioassay data corroborated the beneficial effect of N on the efficiency of applied S. (author)

Uptake of 67Ga in the heart of rats treated with isoproterenol

International Nuclear Information System (INIS)

Sasaki, T.; Kojima, S.; Kubodera, A.

1982-01-01

Gallium-67 citrate ( 67 Ga) accumulation and various enzyme activities during the repair of rat heart with infarct-like lesions induced by isoproterenol (ISP) treatment were measured for 10 days after treatment. Serum creatine phosphokinase (CPK) and glutamic oxalacetic transaminase (GOT) activities were increased immediately after ISP treatment, reaching maximum levels of activity of 545+-64 U/ml and 542+-94 KU/ml, respectively, within 12 h. Uptake of 67 Ga in the rat heart was elevated 12 h after ISP treatment, reaching a maximum on day 1 (0.267+-0.020% dose/g heart). This pattern was essentially similar to the pattern of uronic acid content in the 1.2 M NaCl fraction, which contained mainly heparan sulfate (HS). The activity of glucose-6-phosphate dehydrogenase (G-6-PDH), a marker enzyme for fibrogenesis of damaged tissues, was also elevated 12 h after the ISP treatment, reaching a maximum of approximately 2.47 times that of the control heart on day 1. On the other hand, there were no significant changes in the 67 Ga uptake and uronic acid content in any of the fractions of the liver and kidneys. These findings suggested that HS might be an acceptor for 67 Ga accumulation during the repair of rat heart with infarct-like lesions, in accord with our previous results on CCl 4 -damaged rat liver. (orig.)

Arsenic uptake by Lemna minor in hydroponic system.

Science.gov (United States)

Goswami, Chandrima; Majumder, Arunabha; Misra, Amal Kanti; Bandyopadhyay, Kaushik

2014-01-01

Arsenic is hazardous and causes several ill effects on human beings. Phytoremediation is the use of aquatic plants for the removal of toxic pollutants from external media. In the present research work, the removal efficiency as well as the arsenic uptake capacity of duckweed Lemna minor has been studied. Arsenic concentration in water samples and plant biomass were determined by AAS. The relative growth factor of Lemna minor was determined. The duckweed had potential to remove as well as uptake arsenic from the aqueous medium. Maximum removal of more than 70% arsenic was achieved atinitial concentration of 0.5 mg/1 arsenic on 15th day of experimental period of 22 days. Removal percentage was found to decrease with the increase in initial concentration. From BCF value, Lemna minor was found to be a hyperaccumulator of arsenic at initial concentration of 0.5 mg/L, such that accumulation decreased with increase in initial arsenic concentration.

Enantio-selective molecular dynamics of (±)-o,p-DDT uptake and degradation in water-sediment system.

Science.gov (United States)

Ali, Imran; Alharbi, Omar M L; Alothman, Zeid A; Alwarthan, Abdulrahman

2018-01-01

Enantio-selective molecular dynamics of (±)-o,p-DDT uptake and degradation in water-sediment system is described. Both uptake and degradation processes of (-)-o,p-DDT were slightly higher than (+)-o,p-DDT enantiomer. The optimized parameters for uptake were 7.0μgL -1 concentration of o,p-DDT, 60min contact time, 5.0pH, 6.0gL -1 amount of reverine sediment and 25°C temperature. The maximum degradation of both (-)- and (+)-o,p-DDT was obtained with 16 days, 0.4μgL -1 concentration of o,p-DDT, pH 7 and 35°C temperature. Both uptake and degraded process followed first order rate reaction. Thermodynamic parameters indicated exothermic nature of uptake and degradation processes. Both uptake and degradation were slightly higher for (-)-enantiomer in comparison to (+)-enantiomer of o,p-DDT. It was concluded that both uptake and degradation processes are responsible for the removal of o,p-DDT from nature but uptake plays a crucial role. The percentage degradations of (-)- and (+)-o,p-DDT were 30.1 and 29.5, respectively. This study may be useful to manage o,p-DDT contamination of our earth's ecosystem. Copyright © 2017. Published by Elsevier Inc.

The uptake of radioactive phosphorus by brown trout (Salmo trutta L.) from water and food

International Nuclear Information System (INIS)

Winpenny, K.; Knowles, J.F.; Smith, D.L.

1998-01-01

Brown trout were exposed to 32 P in their tank water (7.4 Bq l -1 ) and the uptake to muscle followed over 6 weeks. A steady-state concentration factor (C ss ) of 1.7 and a biological half-time for clearance (tb1/2)) of 45 days were calculated from the results. The low C ss ) indicates that uptake from water is not a major route of 32 P accumulation in these fish. Brown trout were given a single 32 P-spiked meal, and the uptake and clearance in muscle, liver and blood followed over 6 weeks. Assimilation of the isotope by these organs was low, the maximum activity in whole muscle reaching only 0.2-0.4% of that in the meal with lower values in the other two organs. There was no appreciable clearance of 32 P from muscle during the experiment. The slow clearance of 32 P after uptake from water and lack of any clearance after uptake from food indicates that the C ss for this isotope following uptake by either route is likely to depend on radioactive decay rather than intake rate and physiological clearance. (author)

Radioiodine treatment of hyperthyroidism in patients with low thyroid iodine uptake

International Nuclear Information System (INIS)

Ruchala, M.; Sowinski, J.; Dolata, M.; Skiba, A.; Gembicki, M.; Junik, R.

2005-01-01

The aim of the study was to analyze the effectiveness of radioactive 131I in hyperthyroid patients with confirmed lowered iodine uptake as compared to patients with an uptake of over 30%. We retrospectively analyzed 53 consecutive patients aged from 29 to 84 (mean age 60 years) suffering from hyperthyroidism caused by Graves disease or toxic nodular goitre. The patients were divided into 2 sub-groups: the 1 st with a maximum iodine uptake of 18.7 ± 3.2% (range, 11 - 23%) - 24 patients; the 2 nd with a maximum iodine uptake of 27.1 ± 2.1% (range, 24 - 30%) - 29 patients. The control group consisted of 50 patients treated with 131I with an iodine uptake of over 30%. Each patient was evaluated before, and 6 months after, treatment for fT3, fT4 and TSH with ECLIA; TRAb with RIA; ultrasound with a 7.5 MHz linear probe. The volume of the thyroid gland was determined using the Gutekunst method. All these factors underwent statistical analysis and were considered along with the results of clinical examinations. Clinical remission of hyperthyroidism was evident in 79.3% of both sub-groups, in total (83.3% and 75.3%, respectively). TSH was normalized in 62.3% of these patients (54.2% and 69.0%, respectively). The mean range of TSH levels increased from 0.081 mU/ml to 4.0 mU/ml after therapy; that is, from 0.087 mU/ml to 4.97 mU/ml in the 1 st sub-group and from 0.076 mU/ml to 3.3 mU/ml in the 2 nd sub-group. The volume of the thyroid gland was uniformly significantly lower, with a mean range of 40.5 ml before treatment and 21.7 ml afterwards.The results seen in both sub-groups were similar; only age and dose of radioiodine were slightly higher in the 1 st , while mean uptake was higher in the 2 nd . By comparison of these results to those of the control patients, we observed that the values of TSH, as well as thyroid volume and evidence of clinical remission, reflected those found in the control group.The mean dose of 131I was lower in the control group, that is 11.3 m

Chloride and sodium uptake potential over an entire rotation of Populus irrigated with landfill leachate.

Science.gov (United States)

Zalesny, Jill A; Zalesny, Ronald S

2009-07-01

There is a need for information about the response of Populus genotypes to repeated application of high-salinity water and nutrient sources throughout an entire rotation. We have combined establishment biomass and uptake data with mid- and full-rotation growth data to project potential chloride (Cl-) and sodium (Na+) uptake for 2- to 11-year-old Populus in the north central United States. Our objectives were to identify potential levels of uptake as the trees developed and stages of plantation development that are conducive to variable application rates of high-salinity irrigation. The projected cumulative uptake of Cl- and Na+ during mid-rotation plantation development was stable 2 to 3 years after planting but increased steadily from year 3 to 6. Year six cumulative uptake ranged from 22 to 175 kg Cl- ha(-1) and 8 to 74 kg Na+ ha(-1), while annual uptake ranged from 8 to 54 kg Cl- ha(-1) yr(-1) and 3 to 23 kg Na+ ha(-1) yr(-1). Full-rotation uptake was greatest from 4 to 9 years (Cl-) and 4 to 8 years (Na+), with maximum levels of Cl- (32 kg ha(-1) yr(-1)) and Na+ (13 kg ha(-1) yr(-1)) occurring in year six. The relative uptake potential of Cl- and Na+ at peak accumulation (year six) was 2.7 times greater than at the end of the rotation.

Kinetics of zinc uptake and exchange by primary cultures of rat hepatocytes

International Nuclear Information System (INIS)

Pattison, S.E.; Cousins, R.J.

1986-01-01

The kinetics of 65 Zn 2+ uptake and exchange by hepatocytes in primary culture have been examined in detail to provide a basis for analyzing hormonal regulation of hepatic zinc metabolism. 65 Zn 2+ uptake was found to be a biphasic process. The slow phase represents an exchange between Zn 2+ in the medium and preexisting, intracellular zinc pools. This exchange rate was saturable with a medium zinc concentration of 9.5 microM eliciting one-half the maximum exchange rate and a maximum exchange rate of 9.9 pmol Zn 2+ . min-1 . mg protein-1 in the presence of bovine serum albumin. In the absence of albumin, a secondary, nonsaturable uptake rate was observed. The slow phase was relatively selective, and of the divalent transition metal ions tested, only Cd 2+ and Mn 2+ caused inhibition. The rate of exchange suggests total hepatocyte zinc has a turnover rate of approximately 30 h. The fast phase of 65 Zn 2+ reflects net Zn 2+ accumulation into a labile pool. The initial rates for this process were too fast to be measured accurately, but steady-state measurements allowed determination of the labile pool size. The pool dimensions saturated in the presence [Kapp = 28.6 microM; pool capacity = 0.44 nmol Zn 2+ /mg protein] and absence [Kapp = 11.8 microM; pool capacity = 0.34 nmol Zn 2+ /mg protein] of bovine serum albumin. Kinetics and equilibria of Zn 2+ uptake into the labile pool suggest that the latter acts as a source of Zn 2+ for the slow-exchange phase. Dexamethasone stimulated slow Zn 2+ exchange and also increased the labile pool size. The data suggest physiological factors alter hepatic zinc metabolism by influencing both intracellular Zn 2+ pools

Highly selective and stable carbon dioxide uptake in polyindole-derived microporous carbon materials.

Science.gov (United States)

Saleh, Muhammad; Tiwari, Jitendra N; Kemp, K Christain; Yousuf, Muhammad; Kim, Kwang S

2013-05-21

Adsorption with solid sorbents is considered to be one of the most promising methods for the capture of carbon dioxide (CO₂) from power plant flue gases. In this study, microporous carbon materials used for CO₂ capture were synthesized by the chemical activation of polyindole nanofibers (PIF) at temperatures from 500 to 800 °C using KOH, which resulted in nitrogen (N)-doped carbon materials. The N-doped carbon materials were found to be microporous with an optimal adsorption pore size for CO₂ of 0.6 nm and a maximum (Brunauer-Emmett-Teller) BET surface area of 1185 m(2) g(-1). The PIF activated at 600 °C (PIF6) has a surface area of 527 m(2) g(-1) and a maximum CO₂ storage capacity of 3.2 mmol g(-1) at 25 °C and 1 bar. This high CO₂ uptake is attributed to its highly microporous character and optimum N content. Additionally, PIF6 material displays a high CO₂ uptake at low pressure (1.81 mmol g(-1) at 0.2 bar and 25 °C), which is the best low pressure CO₂ uptake reported for carbon-based materials. The adsorption capacity of this material remained remarkably stable even after 10 cycles. The isosteric heat of adsorption was calculated to be in the range of 42.7-24.1 kJ mol(-1). Besides the excellent CO₂ uptake and stability, PIF6 also exhibits high selectivity values for CO₂ over N₂, CH₄, and H₂ of 58.9, 12.3, and 101.1 at 25 °C, respectively, and these values are significantly higher than reported values.

Thyroid uptake test

International Nuclear Information System (INIS)

Ganatra, R.D.

1992-01-01

The uptake of radioiodine by the thyroid gland is altered by the iodine content of diet or drugs. American diet has a high iodine content because each slice of the white bread contains nearly 150μg of iodine due to the bleaching process employed in the production of the bread. This carrier content of iodine reduces the uptake so much, that the normal American uptakes are usually three to four times lower than the uptakes in the developing countries. The other drawback of the thyroid uptake test is that it is affected by the iodine containing drugs. Anti-diarrhoea medications are quire common in the developing countries and many of them contain iodine moiety. Without a reliable drug history, a low thyroid uptake value may lead to a misleading conclusion

Maximum standard uptake value on pre-chemotherapeutic FDG-PET is a significant parameter for disease progression of newly diagnosed lymphoma

International Nuclear Information System (INIS)

Eo, Jae Seon; Lee, Won Woo; Chung, June Key; Lee, Myung Chul; Kim, Sang Eun

2005-01-01

F-18 FDG-PET is useful for detection and staging of lymphoma. We investigated the prognostic significance of maximum standard uptake (maxSUV) value of FDG-PET for newly diagnosed lymphoma patients before chemotherapy. Twenty-seven patients (male: female = 17: 10: age: 49±19 years) with newly diagnosed lymphoma were enrolled. Nine-teen patients suffered from B cell lymphoma, 6 Hodgkins disease and 2 T cell lymphoma. One patient was stage I, 9 stage II, 3 stage III, 1 stage IV and 13 others. All patients underwent FDG-PET before initiation of chemotherapy. MaxSUV values using lean body weight were obtained for main and largest lesion to represent maxSUV of the patients. The disease progression was defined as total change of the chemotherapeutic regimen or addition of new chemotherapeutic agent during follow up period. The observed period was 389±224 days. The value of maxSUV ranged from 3 to 18 (mean±SD = 10.6±4.4). The disease progressions occurred in 6 patients. Using Cox proportional-hazard regression analysis, maxSUV was identified as a significant parameter for the disease progression free survival (p=0.044). Kaplan-Meier survival curve analysis revealed that the group with higher maxSUV (=10.6, n=5) suffered from shorter disease progression free survival (median 299 days) than the group with lower maxSUV (<10.6, n = 22) (median 378 days, p=0.0146). We found that maxSUV on pre-chemotherapeutic F-18 FDG-PET for newly diagnosed lymphoma patients is a significant parameter for disease progression. Lymphoma patients can be stratified before initiation of chemotherapy in terms of disease progression by the value of maxSUV 10.6

Estimation of the Maximum Theoretical Productivity of Fed-Batch Bioreactors

Energy Technology Data Exchange (ETDEWEB)

Bomble, Yannick J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); St. John, Peter C [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Crowley, Michael F [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2017-10-18

A key step towards the development of an integrated biorefinery is the screening of economically viable processes, which depends sharply on the yields and productivities that can be achieved by an engineered microorganism. In this study, we extend an earlier method which used dynamic optimization to find the maximum theoretical productivity of batch cultures to explicitly include fed-batch bioreactors. In addition to optimizing the intracellular distribution of metabolites between cell growth and product formation, we calculate the optimal control trajectory of feed rate versus time. We further analyze how sensitive the productivity is to substrate uptake and growth parameters.

Comparative study of the radionuclide uptake and distribution within plants for barley and maize varieties

International Nuclear Information System (INIS)

Kostyuk, O.

1998-01-01

Differences in the Cs-134 and Sr-85 uptake by three barley and two maize varieties were investigated in a water culture experiment. In barley, the maximum differences were about 30% for cesium and 50% for strontium. The differences between the maize varieties were negligible. The maximum difference between the varieties of the two species of crops was approximately 30% for cesium and 1 70% for strontium with higher radionuclide uptake by maize. All barley varieties accumulated cesium nearly 3.5 times more effectively than strontium, whereas for the maize varieties, cesium was accumulated about 2 times more effectively. There is a large difference in the radionuclide distribution within the plants: the amount of radiocesium in the green part of plants of both species was approximately 30% of the total, while for radiostrontium it was about 80%. As a result, approximately the same amount of the radionuclides were present in the green part of plants, despite the large difference in the uptake of the radionuclides by the whole plants. It is concluded that crop selection as a provision to reduce radionuclide contamination of the food chain should only be applied taking into account the different radionuclide distributions within the plants

Muscular Oxygen Uptake Kinetics in Aged Adults.

Science.gov (United States)

Koschate, J; Drescher, U; Baum, K; Eichberg, S; Schiffer, T; Latsch, J; Brixius, K; Hoffmann, U

2016-06-01

Pulmonary oxygen uptake (V˙O2) kinetics and heart rate kinetics are influenced by age and fitness. Muscular V˙O2 kinetics can be estimated from heart rate and pulmonary V˙O2. In this study the applicability of a test using pseudo-random binary sequences in combination with a model to estimate muscular V˙O2 kinetics was tested. Muscular V˙O2 kinetics were expected to be faster than pulmonary V˙O2 kinetics, slowed in aged subjects and correlated with maximum V˙O2 and heart rate kinetics. 27 elderly subjects (73±3 years; 81.1±8.2 kg; 175±4.7 cm) participated. Cardiorespiratory kinetics were assessed using the maximum of cross-correlation functions, higher maxima implying faster kinetics. Muscular V˙O2 kinetics were faster than pulmonary V˙O2 kinetics (0.31±0.1 vs. 0.29±0.1 s; p=0.004). Heart rate kinetics were not correlated with muscular or pulmonary V˙O2 kinetics or maximum V˙O2. Muscular V˙O2 kinetics correlated with maximum V˙O2 (r=0.35; p=0.033). This suggests, that muscular V˙O2 kinetics are faster than estimates from pulmonary V˙O2 and related to maximum V˙O2 in aged subjects. In the future this experimental approach may help to characterize alterations in muscular V˙O2 under various conditions independent of motivation and maximal effort. © Georg Thieme Verlag KG Stuttgart · New York.

Nitrogen uptake and regeneration in a frontal region of the Algerian current (western Mediterranean Sea): new evaluation of new production

International Nuclear Information System (INIS)

Gentilhomme, V.; Raimbault, P.

1994-01-01

The uptake and regeneration of four forms of nitrogen (NO 3 - , NO 2 - , NH 4 + and urea) have been studied, in the euphotic layer of a frontal area (Algerian current), in relation with hydrological, chemical and biological parameters. In this area vertical stratification is pronounced; a deep chlorophyll maximum at the bottom of the euphotic layer is present. Results show the importance of measuring urea uptake and regeneration in the study of nitrogen cycling, because this component can be regenerated as rapidly as ammonia, and is a source of nitrogen for phytoplankton. Other results show the oxidation of ammonia to nitrate in the euphotic layer, and particularly at the base of this layer. This nitrification is a source or in situ regenerated nitrate, and could lead to a wrong estimation of the new production estimation. In the deep chlorophyll maximum, there is a maximum of nitrogen primary production but not a maximum of new production. In fact, regenerated production is the most important process over the whole euphotic layer of the Algerian basin. (authors). 56 refs., 2 figs., 2 tabs

Hydroponic uptake of atrazine and lambda-cyhalothrin in Juncus effusus and Ludwigia peploides.

Science.gov (United States)

Bouldin, J L; Farris, J L; Moore, M T; Smith, S; Cooper, C M

2006-11-01

Phytoremediation encompasses an array of plant-associated processes known to mitigate contaminants from soil, sediment, and water. Modification of pesticides associated with agricultural runoff includes processes directly associated with aquatic macrophytes in addition to changes in soil geochemistry and associated rhizospheric degradation. Remediation attributes of two vegetative species common to agricultural drainages in the Mississippi Delta, USA, were assessed using atrazine and lambda-cyhalothrin. Concentrations used in 8-d hydroponic exposures were calculated using recommended field applications and a 5% runoff model from a 0.65-cm rainfall event on a 2.02-ha field. While greater atrazine uptake was measured in Juncus effusus, greater lambda-cyhalothrin uptake occurred in Ludwigia peploides. Maximum pesticide uptake was reached within 48h for each exposure and subsequent translocation of pesticides to upper plant biomass occurred in macrophytes exposed to atrazine. Sequestration of 98.2% of lambda-cyhalothrin in roots of L. peploides was measured after 8d. Translocation of lambda-cyhalothrin in J. effusus resulted in 25.4% of pesticide uptake partitioned to upper plant biomass. These individual macrophyte remediation studies measured species- and pesticide-specific uptake rates, indicating that seasonality of pesticide applications and macrophyte emergence might interact strongly to enhance mitigation capabilities in edge-of-field conveyance structures.

Ouabain-sensitive Rb+ uptake in mouse eggs and preimplantation conceptuses

International Nuclear Information System (INIS)

Van Winkle, L.J.; Campione, A.L.

1991-01-01

The results of histochemical and immunocytochemical studies have been used elsewhere to support the hypothesis that Na+/K(+)-ATPase expression is initiated or increases dramatically in preimplantation mouse conceptuses just before they begin to cavitate. Moreover, localization of the enzyme in the inner membrane of the mural trophoblast is thought to be involved directly in formation and maintenance of the blastocyst cavity. Presumably, Na+/K(+)-ATPase extrudes the cation, Na+, and therefore water into the cavity. The cation transporting activity of the enzyme can be determined by measuring ouabain-sensitive Rb+ uptake by cells. Therefore, we measured Rb+ uptake in mouse eggs and preimplantation conceptuses at various stages of development. 86Rb+ uptake by conceptuses increased linearly with time for at least 60 min in medium containing 0.7 mM total Rb+ plus K+ in the absence or presence of 1.0 mM ouabain, and ouabain inhibited more than 70% of 86Rb+ uptake. The ouabain concentration at 1/2 of maximum inhibition of the ouabain-sensitive component of 86Rb+ uptake was about 10-20 microM in eggs and conceptuses at all stages of preimplantation development. Moreover, ouabain-sensitive Rb+ uptake had a twofold higher Vmax value in blastocysts than in eggs or conceptuses at earlier stages of development (i.e., approximately 173 vs 70-100 fmole.conceptus-1.min-1), although the total cell surface area also was probably about two times greater in blastocysts than in eggs or other conceptuses. Ouabain-sensitive Rb+ transport in eggs and conceptuses may have occurred via a single ouabain-sensitive Rb+ transporter with a Hill coefficient of 1.5-1.8 (Hill plots). When it was assumed that the Hill coefficient had a value of 2.0, however, eggs and conceptuses appeared to contain at least two forms of Na+/K(+)-ATPase activity

Albumin-derived peptides efficiently reduce renal uptake of radiolabelled peptides

International Nuclear Information System (INIS)

Vegt, Erik; Eek, Annemarie; Oyen, Wim J.G.; Gotthardt, Martin; Boerman, Otto C.; Jong, Marion de

2010-01-01

In peptide-receptor radionuclide therapy (PRRT), the maximum activity dose that can safely be administered is limited by high renal uptake and retention of radiolabelled peptides. The kidney radiation dose can be reduced by coinfusion of agents that competitively inhibit the reabsorption of radiolabelled peptides, such as positively charged amino acids, Gelofusine, or trypsinised albumin. The aim of this study was to identify more specific and potent inhibitors of the kidney reabsorption of radiolabelled peptides, based on albumin. Albumin was fragmented using cyanogen bromide and six albumin-derived peptides with different numbers of electric charges were selected and synthesised. The effect of albumin fragments (FRALB-C) and selected albumin-derived peptides on the internalisation of 111 In-albumin, 111 In-minigastrin, 111 In-exendin and 111 In-octreotide by megalin-expressing cells was assessed. In rats, the effect of Gelofusine and albumin-derived peptides on the renal uptake and biodistribution of 111 In-minigastrin, 111 In-exendin and 111 In-octreotide was determined. FRALB-C significantly reduced the uptake of all radiolabelled peptides in vitro. The albumin-derived peptides showed different potencies in reducing the uptake of 111 In-albumin, 111 In-exendin and 111 In-minigastrin in vitro. The most efficient albumin-derived peptide (peptide 6), was selected for in vivo testing. In rats, 5 mg of peptide 6 very efficiently inhibited the renal uptake of 111 In-minigastrin, by 88%. Uptake of 111 In-exendin and 111 In-octreotide was reduced by 26 and 33%, respectively. The albumin-derived peptide 6 efficiently inhibited the renal reabsorption of 111 In-minigastrin, 111 In-exendin and 111 In-octreotide and is a promising candidate for kidney protection in PRRT. (orig.)

Plant uptake of dual-labeled organic N biased by inorganic C uptake

DEFF Research Database (Denmark)

Rasmussen, Jim; Sauheitl, Leopold; Eriksen, Jørgen

2010-01-01

glycine or CO2-3 , but found no differences in uptake rates between these C-sources. The uptake of inorganic C to the shoot tissue was higher for maize grown in full light compared to shading, which indicates a passive uptake of inorganic C with water. We conclude that uptake of inorganic C produced...

Incidental Focal 18F FDG Uptake in the Prostate: Clinical Significance and Differential Diagnostic Criteria

International Nuclear Information System (INIS)

Cho, Suk Kyong; Choi, Joon Young; Yoo, Jang; Cheon, Miju; Lee, Ji Young; Hyun, Seung Hyup; Lee, Eun Jeong; Lee, Kyung Han; Kim, Byung Tae

2011-01-01

The extent and intensity of 18F FDG uptake in prostate cancer patients are known to be variable, and the clinical significance of focal 18F fluorodeoxyglucose ( 18F FDG) uptake that is incidentally found on positron emission tomography (PET) has not been established. We investigated the clinical significance of incidental focal prostate uptake of 18F FDG on PET/computed tomography (CT) and analyzed differential findings on PET/CT Between malignant and benign uptake. A total of 14,854 whole body 18F FDG PET/CT scans (4,806 that were conducted during cancer screening and 10,048 that were conducted to evaluate suspected of alleged cancer outside of the prostate) were retrospectively reviewed to determine the presence, location, multiplicity reviewed to determine the presence, location, multiplicity and maximum standardized uptake value (SUVmax) of focal prostate uptake and combined calcification. The final diagnosis determined by serum prostate specific antigen (PSA) level and biopsy was compared with PET findings. Incidental focal prostate uptake was observed in 148 of 14,854 scans (1.0%). Sixty seven of these 148 subjects who had diagnostic confirmation were selected for further analysis. Prostate cancer was diagnosed in nine of 67 subjects (13.4%). The remaining 58 subjects had no malignancy in the prostate based on normal serum PSA level (n=53), or elevated serum PSA level with a negative biopsy result (n=5). While 84.6% (11/13) of malignant uptake was peripherally located in the prostate glands, 60.2% (50/83) of benign uptake was centrally located (p 18F FDG uptake un the prostate is not common, the incidence of cancer with focal uptake is not low. Therefore, these findings deserve further evaluation. The location of the focal prostate uptake may help with the selection of high risk prostate cancer patients.

Inorganic carbon uptake during photosynthesis. II. Uptake by isolated Asparagus mesophyll cells during isotopic disequilibrium

International Nuclear Information System (INIS)

Espie, G.S.; Owttrim, G.W.; Colman, B.

1986-01-01

The species of inorganic carbon (CO 2 or HCO 3 - ) taken up as a source of substrate for photosynthetic fixation by isolated Asparagus sprengeri mesophyll cells is investigated. Discrimination between CO 2 or HCO 3 - transport, during steady state photosynthesis, is achieved by monitoring the changes (by 14 C fixation) which occur in the specific activity of the intracellular pool of inorganic carbon when the inorganic carbon present in the suspending medium is in a state of isotopic disequilibrium. Quantitative comparisons between theoretical (CO 2 or HCO 3 - transport) and experimental time-courses of 14 C incorporation, over the pH range of 5.2 to 7.5, indicate that the specific activity of extracellular CO 2 , rather than HCO 3 - , is the appropriate predictor of the intracellular specific activity. It is concluded, therefore, that CO 2 is the major source of exogenous inorganic carbon taken up by Asparagus cells. However, at high pH (8.5), a component of net DIC uptake may be attributable to HCO 3 - transport, as the incorporation of 14 C during isotopic disequilibrium exceeds the maximum possible incorporation predicted on the basis of CO 2 uptake alone. The contribution of HCO 3 - to net inorganic carbon uptake (pH 8.5) is variable, ranging from 5 to 16%, but is independent of the extracellular HCO 3 - concentration. The evidence for direct HCO 3 - transport is subject to alternative explanations and must, therefore, be regarded as equivocal. Nonlinear regression analysis of the rate of 14 C incorporation as a function of time indicates the presence of a small extracellular resistance to the diffusion of CO 2 , which is partially alleviated by a high extracellular concentration of HCO 3 -

Dependency of maximum goitrogenic response on some minimal level of thyroid hormone production

International Nuclear Information System (INIS)

March, B.E.; Poon, R.

1981-01-01

Thyroidal activity was studied in chicks given dietary thiouracil in conjunction with daily doses of thyroxine and with diets adequate and deficient in iodine. DL-thyroxine administered at doses up to 1.0 microgram per day for 10 to 12 days had no effect or slightly increased thyroid weight. Both the epithelial and colloid components of the thyroid gland were increased in response to thiouracil and to thiouracil in combination with low dosages of exogenous thyroxine. Radioiodine uptake was increased above the control with thiouracil and with thiouracil in conjunction with .5 and 1.0 microgram DL-thyroxine given daily. Birds receiving thiouracil, with and without exogenous thyroxine, showed a different pattern of radioiodine uptake and release than the control birds. Thiouracil-treated birds showed a rapid uptake of iodine following its administration, which was followed by a rapid decline immediately after peak accumulation, whereas in control birds thyroidal radioiodine concentration reached a plateau at the maximum concentration attained. The goitrogenic response to thiouracil was much greater when the diet was supplemented with iodine than when the diet was iodine-deficient. Thyroids under iodine deficiency contained greater percentages of epithelial tissue than with iodine-supplemented diets. Thyroid glands of chicks given thiouracil in an iodine-supplemented diet contained much more colloid than glands from iodine-deficient chicks with or without thiouracil. DL-thyroxine at a dosage of .5 microgram per day to chicks given thiouracil in an iodine-adequate diet increased, whereas higher dosages decreased thyroidal colloid. It is concluded that some minimal concentration of thyroid hormone is required for maximum goitrogenic response. It is not clear whether the response is entirely due to an effect on thyrotropin production or whether there is an effect of thyroid hormone on the thyroid gland itself

FDG uptake in cervical lymph nodes in children without head and neck cancer.

Science.gov (United States)

Vali, Reza; Bakari, Alaa A; Marie, Eman; Kousha, Mahnaz; Charron, Martin; Shammas, Amer

2017-06-01

Reactive cervical lymphadenopathy is common in children and may demonstrate increased 18 F-fluoro-deoxyglucose ( 18 F-FDG) uptake on positron emission tomography/computed tomography (PET/CT). We sought to evaluate the frequency and significance of 18 F-FDG uptake by neck lymph nodes in children with no history of head and neck cancer. The charts of 244 patients (114 female, mean age: 10.4 years) with a variety of tumors such as lymphoma and post-transplant lymphoproliferative diseases (PTLD), but no head and neck cancers, who had undergone 18 F-FDG PET/CT were reviewed retrospectively. Using the maximum standardized uptake value (SUVmax), increased 18 F-FDG uptake by neck lymph nodes was recorded and compared with the final diagnosis based on follow-up studies or biopsy results. Neck lymph node uptake was identified in 70/244 (28.6%) of the patients. In 38 patients, the lymph nodes were benign. In eight patients, the lymph nodes were malignant (seven PTLD and one lymphoma). In 24 patients, we were not able to confirm the final diagnosis. Seven out of the eight malignant lymph nodes were positive for PTLD. The mean SUVmax was significantly higher in malignant lesions (4.2) compared with benign lesions (2.1) (P = 0.00049). 18 F-FDG uptake in neck lymph nodes is common in children and is frequently due to reactive lymph nodes, especially when the SUVmax is cervical lymph nodes is higher in PTLD patients compared with other groups.

Clinical Significance of Diffuse {sup 18F} FDG Uptake in Residual Thyroid Gland after Unilateral Thyroid Lobectomy

Energy Technology Data Exchange (ETDEWEB)

Song, Hee Sung; Lee, Su Jin; Yoon, Seok Ho; Lee, Jandee; Soh, Euy Young; An, Young Sil; Yoon, Joon Kee [Ajou Univ. School of Medicine, Suwon (Korea, Republic of)

2011-09-15

We investigated the clinical significance of diffuse uptake in remaining thyroid after unilateral lobectomy for thyroid cancer. A total of 144 thyroid cancer patients who underwent {sup 18F} FDG PET/CT after lobectomy were evaluated for the presence of diffuse {sup 18F} FDG uptake with maximum SUV (SUVmax)>2.0 in the residual thyroid and placed into one of two groups: with diffuse uptake and without diffuse uptake group. Clinical, laboratory, and PET/CT parameters in both groups were compared. Correlations between SUVmax of thyroid and available parameters were analyzed. Forty two of 144 patients (29.2%) had diffuse thyroid uptake (mean SUVmax: 3.2{+-}1.1). All patients with diffuse uptake and 96 (94.1%) without diffuse uptake were receiving thyroxine therapy (P=0.09). Thyroid function tests showed that most patients were euthyroid status (78.6 vs. 85.3%, P=0.36). TgAb levels were significantly higher in patients with diffuse uptake (338.0{+-}664.6 vs. 57.3{+-}46.4, P<0.0001). Mean attenuation values in the diffuse uptake group were significantly lower (72.2{+-}15. vs. 97.0{+-}16.0, P<0.0001). An inverse correlation was found between SUVmax and mean attenuation values of residual thyroid in all patients (r=-0.57, P<0.0001) and subgroup with diffuse uptake (r=-0.31, P<0.05). In this study, diffuse {sup 18F} FDG uptake in the residual thyroid after unilateral lobectomy was a relatively frequent finding and may be associated with chronic thyroiditis. This uptake is not influenced by thyroid status or thyroxine therapy. The {sup 18F} FDG uptake is inversely correlated with mean attenuation value of thyroid.

Uptake of Cd(II Using Natural Zeolite: Batch and Continuous Fixed-Bed Studies

Directory of Open Access Journals (Sweden)

Luna M. LMarashdeh

2009-12-01

Full Text Available Uptake of Cd(II ions by natural phillipsite tuff was investigated both in shake-flask and fixed-bed columns. Equilibrium uptake, qe, was found to best fit Langmuir adsorption isotherm with a maximum value of 25.78 mg/g. Percent removal of Cd ions was close to 100% from initial metal ion concentrations in the range 50 - 75 mg/L at 5.0 g zeolite/L. Also, qe was found to vary exponentially with zeolite dose. Break points as high as 350 minutes were obtained from bed treatment at favorable conditions of a low solution flow rate and high bed depth. In batch experiments, equilibrium pH increased to < 8.0 excluding chemical precipitation as part of the removal while in fixed-beds the final pH exceeded 9.0. It is suggested that a sieve action of zeolite porous structure plays a role as an uptake mechanism in addition to the ion exchange.

Maximum Aerobic Capacity of Underground Coal Miners in India

Directory of Open Access Journals (Sweden)

Ratnadeep Saha

2011-01-01

Full Text Available Miners fitness test was assessed in terms of determination of maximum aerobic capacity by an indirect method following a standard step test protocol before going down to mine by taking into consideration of heart rates (Telemetric recording and oxygen consumption of the subjects (Oxylog-II during exercise at different working rates. Maximal heart rate was derived as 220−age. Coal miners reported a maximum aerobic capacity within a range of 35–38.3 mL/kg/min. It also revealed that oldest miners (50–59 yrs had a lowest maximal oxygen uptake (34.2±3.38 mL/kg/min compared to (42.4±2.03 mL/kg/min compared to (42.4±2.03 mL/kg/min the youngest group (20–29 yrs. It was found to be negatively correlated with age (r=−0.55 and −0.33 for younger and older groups respectively and directly associated with the body weight of the subjects (r=0.57 – 0.68, P≤0.001. Carriers showed maximum cardio respiratory capacity compared to other miners. Indian miners VO2max was found to be lower both compared to their abroad mining counterparts and various other non-mining occupational working groups in India.

Kinetics of adsorption and uptake of Cu2+ by Chlorella vulgaris: influence of pH, temperature, culture age, and cations.

Science.gov (United States)

Mehta, S K; Singh, Alpana; Gaur, J P

2002-03-01

Adsorption and uptake of Cu2+ by Chlorella vulgaris were distinguished by extracting the surface-bound Cu2+ with EDTA. The uptake of Cu2+ followed Michaelis Menten kinetics. The maximum rate of Cu2+ uptake (0.362fmolcell(-1) h(-1)) was obtained at pH 6.0. The rate of Cu2+ uptake was greater for cultures in the exponential phase of growth, and increased with a rise in temperature from 6 to 25 degrees C, thus pointing towards an active mechanism. The maximum number of Cu2+ binding sites was 3.245 fmol cell(-1) at pH 4.5. Adsorption of Cu2+ was strongly pH-dependent thereby indicating that the number and nature of metal binding sites on the cell surface change with changing chemistry of the solution. Unlike uptake, the adsorption remained unaffected by small changes in temperature. Older cultures displayed a higher Cu2+ adsorption capacity than the exponentially growing ones thus suggesting generation of new and/or additional Cu2+ binding sites on older cells of C. vulgaris. By pH titration, the cation-exchange capacity of Chlorella, measured in terms of H+/ Na+ exchange, was about 17 fmol cell(-1) at pH 10.5. Negligible cation exchange capacity at and below pH 5.0 indicated that ion exchange was not the sole mechanism of Cu2+ adsorption by Chlorella. The uptake and adsorption of Cu2+ were inhibited by 100 microM of various cations including other heavy metal ions. The general concept that cations competitively inhibit accumulation of metals in living organisms does not hold for C. vulgaris. Non-competitive, uncompetitive and mixed inhibition of Cu2+ uptake and adsorption by various cations were more common than competitive inhibition.

Heart Rate and Oxygen Uptake Kinetics in Type 2 Diabetes Patients - A Pilot Study on the Influence of Cardiovascular Medication on Regulatory Processes.

Science.gov (United States)

Koschate, Jessica; Drescher, Uwe; Baum, Klaus; Brinkmann, Christian; Schiffer, Thorsten; Latsch, Joachim; Brixius, Klara; Hoffmann, Uwe

2017-05-01

The aim of this pilot study was to investigate whether there are differences in heart rate and oxygen uptake kinetics in type 2 diabetes patients, considering their cardiovascular medication. It was hypothesized that cardiovascular medication would affect heart rate and oxygen uptake kinetics and that this could be detected using a standardized exercise test. 18 subjects were tested for maximal oxygen uptake. Kinetics were measured in a single test session with standardized, randomized moderate-intensity work rate changes. Time series analysis was used to estimate kinetics. Greater maxima in cross-correlation functions indicate faster kinetics. 6 patients did not take any cardiovascular medication, 6 subjects took peripherally acting medication and 6 patients were treated with centrally acting medication. Maximum oxygen uptake was not significantly different between groups. Significant main effects were identified regarding differences in muscular oxygen uptake kinetics and heart rate kinetics. Muscular oxygen uptake kinetics were significantly faster than heart rate kinetics in the group with no cardiovascular medication (maximum in cross-correlation function of muscular oxygen uptake vs. heart rate; 0.32±0.08 vs. 0.25±0.06; p=0.001) and in the group taking peripherally acting medication (0.34±0.05 vs. 0.28±0.05; p=0.009) but not in the patients taking centrally acting medication (0.28±0.05 vs. 0.30±0.07; n.s.). It can be concluded that regulatory processes for the achievement of a similar maximal oxygen uptake are different between the groups. The used standardized test provided plausible results for heart rate and oxygen uptake kinetics in a single measurement session in this patient group. © Georg Thieme Verlag KG Stuttgart · New York.

Quantitative Assessment of Radioisotope Uptake in Condyles by SPECT Bone Scintigraphy

Directory of Open Access Journals (Sweden)

Z. Dalili

2006-03-01

Full Text Available Statement of problem: Condylar hyperplasia of the mandible is a self limiting abnormality which can cause facial asymmetry, temporomandibular joint (TMJdysfunction and esthetic problems. Treatment planning is based on the results of isotope scanning, clinical findings and patient age. Single photon emission tomography(SPECT is considered to be a sensitive method in the calculation of condylar uptake differences.Purpose: The aim of this study was to determine the growth activity occurring in the mandibular condyles, and to devise an index of side-to-side differences in condylar activity in different individuals.Material and Methods: 38 patients, with an age range of 13 to 34 years, undergoing skeletal scintigraphy for a variety of conditions, were chosen for this study. 25 mci TC-99 was injected to all subjects in order to assess the difference between right (Rt andleft (Lt condylar uptake percentage and to calculate the Lt to Rt condylar uptake ratio.The normal index was determined.Results: The maximum amount of difference between the uptake of Rt and Lt condyles was 6.2 percent (Lt side and Rt side were 53.1 % and 46.9 %, respectively in the male patients and 5.7 percent in the female patients (Lt side and Rt side were 52.85 % and 47.15 %, respectively. The condylar activity difference and ratio of Lt to Rt condylar uptakes did not show a significant difference between the male and female groups.Conclusion: The difference between the growth activity of RT and LT normal TMJs was less than 6.2 percent.

Changes of FDG brain uptake in patients with abnormal thyroid function

International Nuclear Information System (INIS)

Huang, Wen-Sheng; Chang, Chih-Yung; Cheng, Cheng Yi

2009-01-01

Full text: Objective: To investigate FOG brain uptake in patients with hypo- and subclinical hyperthyroidism undergoing whole-body FOG PET/CT. Methods: Sixty-four patients who had received total thyroidectomy for thyroid carcinoma underwent whole-body FDG PETI CT. Thirty-two of them received imaging in subclinical hyperthyroid status (15 males; 17 females; mean age, 55 ± 14 years) while the other 32 age-matched patients underwent the scan 4 wk after thyroid hormone withdrawal (12 males; 20 females; mean age, 56 ± 13 years). Brain images were performed I h after 370 MBq intravenous injection using a dedicated PET/CT (Siemens Biograph BGO duo). FOG-uptake was quantified by the standardized uptake value (SUY), normalized to patient's body weight. The volume of brain was determined by PET with 40% maximum SUY threshold. The brain mean SUV (SUY mean) were calculated in each patient. Data were compared between the two groups. Results: The brain mean SUYs for the hypothyroid patients ranged between 3.11 and 6.35 (averaged SUY mean 5.13 ± 0.91) while those of the subclinical hyperthyroid patients varied from 3.53 to 8.29 (mean SUY mean 5.77 ± 1.04). There was a significant global reduction of brain FDG uptake in the hypothyroid group (II.] %, P < 0.0 I) but no significant changes in the sub-clinical hyperthyroid group compared to the controls. Conclusion: FDG brain uptake in subclinical hyperthyroid patients was significantly greater than that of patients with hypothyroidism, suggesting effects of thyroid hormone on cerebral glucose metabolism.

Uptake, depuration, and distribution of selenium in Daphnia and its effects on survival and ultrastructure

Energy Technology Data Exchange (ETDEWEB)

Schultz, T.W. (Pan American Univ., Edinburg, TX); Freeman, S.R.; Dumont, J.N.

1980-01-01

Selenium is an important essential nutritional trace element which has been shown to provide protection against certain other metal poisoning. However, it is a suspected carcinogen and teratogen. The uptake, depuration, and toxicity of selenium in Daphnia pulex have been examined. The LC/sub 50/ at 48 and 96 h for juvenile animals is 0.6 mg/L and 0.1 mg/L, respectively, and for adults it is 1.3 mg/L and 0.5 mg/L, respectively. Uptake in adult unfed animals is rapid, reaching a maximum at about 12 h, but depuration is slow. In fed animals, uptake is slower, reaching a maximum at 96 h, but initial depuration is followed by a slower prolonged loss. Localization in cells is primarily in the cytoplasmic compartment although evidence is presented which suggests nucleolar localization. Ultrastructural damage is detected by 16 h after exposure and is initially confined to the mitochondria. Dense deposits accumulate in the mitochondrial matrices. The nature of these deposits is unknown; they may represent a calcium- or phosphate-selenium complex. With time, the mitochondria degenerate. It is clear that relatively low concentrations of selenium are toxic to these aquatic organisms and render them incapable of survival in the natural environment. Concentrations higher than those lethal to Daphnia can be expected, at least in local areas, from the burning or conversion of fossil fuels.

Elucidating the Function of Penetratin and a Static Magnetic Field in Cellular Uptake of Magnetic Nanoparticles

Directory of Open Access Journals (Sweden)

David Stirling

2013-02-01

Full Text Available Nanotechnology plays an increasingly important role in the biomedical arena. In particular, magnetic nanoparticles (mNPs have become important tools in molecular diagnostics, in vivo imaging and improved treatment of disease, with the ultimate aim of producing a more theranostic approach. Due to their small sizes, the nanoparticles can cross most of the biological barriers such as the blood vessels and the blood brain barrier, thus providing ubiquitous access to most tissues. In all biomedical applications maximum nanoparticle uptake into cells is required. Two promising methods employed to this end include functionalization of mNPs with cell-penetrating peptides to promote efficient translocation of cargo into the cell and the use of external magnetic fields for enhanced delivery. This study aimed to compare the effect of both penetratin and a static magnetic field with regards to the cellular uptake of 200 nm magnetic NPs and determine the route of uptake by both methods. Results demonstrated that both techniques increased particle uptake, with penetratin proving more cell specific. Clathrin- medicated endocytosis appeared to be responsible for uptake as shown via PCR and western blot, with Pitstop 2 (known to selectively block clathrin formation blocking particle uptake. Interestingly, it was further shown that a magnetic field was able to reverse or overcome the blocking, suggesting an alternative route of uptake.

In vitro cellular uptake of evodiamine and rutaecarpine using a microemulsion.

Science.gov (United States)

Zhang, Yong-Tai; Huang, Zhe-Bin; Zhang, Su-Juan; Zhao, Ji-Hui; Wang, Zhi; Liu, Ying; Feng, Nian-Ping

2012-01-01

To investigate the cellular uptake of evodiamine and rutaecarpine in a microemulsion in comparison with aqueous suspensions and tinctures. A microemulsion was prepared using the dropwise addition method. Mouse skin fibroblasts were cultured in vitro to investigate the optimal conditions for evodiamine and rutaecarpine uptake with different drug concentrations and administration times. Under optimal conditions, the cellular uptake of microemulsified drugs was assayed and compared to tinctures and aqueous suspensions. Rhodamine B labeling and laser scanning confocal microscopy (LSCM) were used to explore the distribution of fluorochrome transferred with the microemulsion in fibroblasts. Cellular morphology was also investigated, using optical microscopy to evaluate microemulsion-induced cellular toxicity. The maximum cellular drug uptake amounts were obtained with a 20% concentration (v/v) of microemulsion and an 8 hour administration time. Drug uptake by mouse skin fibroblasts was lowest when the drugs were loaded in microemulsion. After incubation with rhodamine B-labeled microemulsion for 8 hours, the highest fluorescence intensity was achieved, and the fluorochrome was primarily distributed in the cytochylema. No obvious cellular morphologic changes were observed with the administration of either the microemulsion or the aqueous suspension; for the tincture group, however, massive cellular necrocytosis was observed. The lower cellular uptake with microemulsion may be due to the fact that most of the drug loaded in the microemulsion vehicle was transported via the intercellular space, while a small quantity of free drug (released from the vehicle) was ingested through transmembrane transport. Mouse skin fibroblasts rarely endocytosed evodiamine and rutaecarpine with a microemulsion as the vehicle. The microemulsion had no obvious effect on cellular morphology, suggesting there is little or no cellular toxicity associated with the administration of microemulsion on

Uptake of /sup 67/Ga in the heart of rats treated with isoproterenol

Energy Technology Data Exchange (ETDEWEB)

Sasaki, T; Kojima, S; Kubodera, A

1982-12-01

Gallium-67 citrate (/sup 67/Ga) accumulation and various enzyme activities during the repair of rat heart with infarct-like lesions induced by isoproterenol (ISP) treatment were measured for 10 days after treatment. Serum creatine phosphokinase (CPK) and glutamic oxalacetic transaminase (GOT) activities were increased immediately after ISP treatment, reaching maximum levels of activity of 545+-64 U/ml and 542+-94 KU/ml, respectively, within 12 h. Uptake of /sup 67/Ga in the rat heart was elevated 12 h after ISP treatment, reaching a maximum on day 1 (0.267+-0.020% dose/g heart). This pattern was essentially similar to the pattern of uronic acid content in the 1.2 M NaCl fraction, which contained mainly heparan sulfate (HS). The activity of glucose-6-phosphate dehydrogenase (G-6-PDH), a marker enzyme for fibrogenesis of damaged tissues, was also elevated 12 h after the ISP treatment, reaching a maximum of approximately 2.47 times that of the control heart on day 1. On the other hand, there were no significant changes in the /sup 67/Ga uptake and uronic acid content in any of the fractions of the liver and kidneys. These findings suggested that HS might be an acceptor for /sup 67/Ga accumulation during the repair of rat heart with infarct-like lesions, in accord with our previous results on CCl/sub 4/-damaged rat liver.

Evaluation of solitary pulmonary nodules by integrated PET/CT: improved accuracy by FDG uptake pattern and CT findings

International Nuclear Information System (INIS)

Joon Young Choi; Kyung Soo Lee; O Jung Kwon; Young Mog Shim; Kyung-Han Lee; Yong Choi; Yearn Seong Choe; Byung-Tae Kim

2004-01-01

Objective: FDG PET is useful to differentiate malignancy from benign lesions in the evaluation of solitary pulmonary nodules (SPNs). However, FDG PET showed false positive results in benign inflammatory lesions such as tuberculosis and organizing pneumonia. Furthermore, malignant tumors such as adenocarcinoma (AC) with bronchioloalveolar carcinoma (BAC) type had lower FDG uptake than other cell types of non-small cell lung cancer. We investigated whether FDG uptake pattern and image findings of CT for attenuation correction could improve accuracy for evaluating SPNs over SUV in integrated PET/CT imaging using FDG. Methods: Forty patients (M:F = 23:17, mean age 58.2±9.4 yrs) with non-calcified SPNs (diameter on CT 30 mm, no significant mediastinal node enlargement, no atelectasis) were included. All subjects underwent integrated PET/CT imaging using FDG. One nuclear medicine physician and 1 chest radiologist interpreted the PET and non-contrast CT images for attenuation correction, respectively. On PET images, maximum SUV of SPN was acquired, and FDG uptake pattern was categorized as diffusely increased or heterogeneously increased with upper threshold of window setting adjusted to maximum SUV of each nodule. A radiologist interpreted SPNs as benign or malignant based on CT images with lung and mediastinai window settings blinded to PET findings. Results: On pathological exam, 30 SPNs were confirmed to be malignant (11 AC with non-BAC type, 8 AC with BAC type, 8 squamous cell carcinoma, 1 adenosquamous cell carcinoma, 1 neuroendocrine carcinoma, 1 large cell carcinoma), and 10 were benign (4 tuberculosis, 3 organizing pneumonia, 2 sclerosing pneumocytoma, 1 non-specific inflammation). All 5 nodules with max SUV 7.0 except one with tuberculoma had malignancy. When only nodules with diffusely increased uptake were considered malignant in indeterminate group with max SUV of 4.0 to 7.0, PET could diagnose 5 of 9 malignant nodules with one false positive nodule. In 6 of

FDG uptake in cervical lymph nodes in children without head and neck cancer

Energy Technology Data Exchange (ETDEWEB)

Vali, Reza; Bakari, Alaa A.; Marie, Eman; Kousha, Mahnaz; Shammas, Amer [University of Toronto, Department of Diagnostic Imaging, The Hospital for Sick Children, Toronto, ON (Canada); Charron, Martin [Brampton Nuclear Services, Toronto, ON (Canada)

2017-06-15

Reactive cervical lymphadenopathy is common in children and may demonstrate increased {sup 18}F-fluoro-deoxyglucose ({sup 18}F-FDG) uptake on positron emission tomography/computed tomography (PET/CT). We sought to evaluate the frequency and significance of {sup 18}F-FDG uptake by neck lymph nodes in children with no history of head and neck cancer. The charts of 244 patients (114 female, mean age: 10.4 years) with a variety of tumors such as lymphoma and post-transplant lymphoproliferative diseases (PTLD), but no head and neck cancers, who had undergone {sup 18}F-FDG PET/CT were reviewed retrospectively. Using the maximum standardized uptake value (SUVmax), increased {sup 18}F-FDG uptake by neck lymph nodes was recorded and compared with the final diagnosis based on follow-up studies or biopsy results. Neck lymph node uptake was identified in 70/244 (28.6%) of the patients. In 38 patients, the lymph nodes were benign. In eight patients, the lymph nodes were malignant (seven PTLD and one lymphoma). In 24 patients, we were not able to confirm the final diagnosis. Seven out of the eight malignant lymph nodes were positive for PTLD. The mean SUVmax was significantly higher in malignant lesions (4.2) compared with benign lesions (2.1) (P = 0.00049). {sup 18}F-FDG uptake in neck lymph nodes is common in children and is frequently due to reactive lymph nodes, especially when the SUVmax is <3.2. The frequency of malignant cervical lymph nodes is higher in PTLD patients compared with other groups. (orig.)

Comparison of FDG Uptake with Pathological Parameters in the Well-differentiated Thyroid Cancer

International Nuclear Information System (INIS)

Choi, Woo Hee; Chung, Yong An; Kim, Ki Jun; Park, Chang Suk; Jung, Hyun Suk; Sohn, Hyung Sun; Chung, Soo Kyo; Yoo, Chang Young

2009-01-01

Differentiated thyroid cancer (DTC) has variable degree of F-18 FDG avidity. The purpose of this study was to evaluate the relationship between F-18 FDG uptake and pathological or immunohistochemical features of DTC. DTC patients who underwent both pre-operative F-18 FDG PET/CT scan and surgery were included in the study. Maximum standardized uptake values (SUVmax) of primary tumor were calculated. If the primary tumor showed no perceptibly increased F-18 FDG uptake, region of interest was drawn based on finding of CT portion of the PET/CT images. Pathological and immunohistochemical markers such as presence of lymph node (LN) metastasis and underlying thyroiditis, tumor size, Ki-67 labeling index, expressions of EGFR, COX-2, and Galectin-3 were evaluated. Total of 106 patients was included (102 papillary carcinomas, 4 follicular carcinomas). The mean SUVmax of the large tumors (above 1 cm) was significantly higher than the mean SUVmax of small (equal to or less than 1 cm) ones (7.8±8.5 vs. 3.6±3.1, p=0.004). No significant difference in F-18 FDG uptake was found according to the presence or absence of LN metastasis and underlying thyroiditis, or the degree of Ki-67 labeling index, expression of EGFR, COX-2 and Galectin-3. In conclusion, the degree of F-18 FDG uptake in DTC was associated with the size of primary tumor. But there seem to be no relationship between F-18 FDG uptake of DTC and expression of Ki-67, EGFR, COX-2 and Galectin-3

Comparison of FDG Uptake with Pathological Parameters in the Well-differentiated Thyroid Cancer

Energy Technology Data Exchange (ETDEWEB)

Choi, Woo Hee; Chung, Yong An; Kim, Ki Jun; Park, Chang Suk; Jung, Hyun Suk; Sohn, Hyung Sun; Chung, Soo Kyo; Yoo, Chang Young [College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of)

2009-02-15

Differentiated thyroid cancer (DTC) has variable degree of F-18 FDG avidity. The purpose of this study was to evaluate the relationship between F-18 FDG uptake and pathological or immunohistochemical features of DTC. DTC patients who underwent both pre-operative F-18 FDG PET/CT scan and surgery were included in the study. Maximum standardized uptake values (SUVmax) of primary tumor were calculated. If the primary tumor showed no perceptibly increased F-18 FDG uptake, region of interest was drawn based on finding of CT portion of the PET/CT images. Pathological and immunohistochemical markers such as presence of lymph node (LN) metastasis and underlying thyroiditis, tumor size, Ki-67 labeling index, expressions of EGFR, COX-2, and Galectin-3 were evaluated. Total of 106 patients was included (102 papillary carcinomas, 4 follicular carcinomas). The mean SUVmax of the large tumors (above 1 cm) was significantly higher than the mean SUVmax of small (equal to or less than 1 cm) ones (7.8{+-}8.5 vs. 3.6{+-}3.1, p=0.004). No significant difference in F-18 FDG uptake was found according to the presence or absence of LN metastasis and underlying thyroiditis, or the degree of Ki-67 labeling index, expression of EGFR, COX-2 and Galectin-3. In conclusion, the degree of F-18 FDG uptake in DTC was associated with the size of primary tumor. But there seem to be no relationship between F-18 FDG uptake of DTC and expression of Ki-67, EGFR, COX-2 and Galectin-3.

Cyclic variations in nitrogen uptake rate of soybean plants: effects of external nitrate concentration

Science.gov (United States)

Tolley-Henry, L.; Raper, C. D. Jr; Granato, T. C.; Raper CD, J. r. (Principal Investigator)

1988-01-01

Net uptake of NO3- by non-nodulated soybean plants [Glycine max (L.) Merr. cv. Ransom] growing in flowing hydroponic cultures containing 0.5, 1.0 and 10.0 mol m-3 NO3- was measured daily during a 24-d period of vegetative development to determine if amplitude of maximum and minimum rates of net NO3- uptake are responsive to external concentrations of NO3-. Removal of NO3- from the replenished solutions during each 24-h period was determined by ion chromatography. Neither dry matter accumulation nor the periodicity of oscillations in net uptake rate was altered by the external NO3- concentrations. The maxima of the oscillations in net uptake rate, however, increased nearly 3-fold in response to external NO3- concentrations. The maxima and minima, respectively, changed from 4.0 and 0.6 mmol NO3- per gram root dry weight per day at an external solution level of 0.5 mol m-3 NO3- to 15.2 and -2.7 mmol NO3- per gram root dry weight per day at an external solution level of 10.0 mol m-3 NO3-. The negative values for minimum net uptake rate from 10.0 mol m-3 NO3- solutions show that net efflux was occurring and indicate that the magnitude of the efflux component of net uptake was responsive to external concentration of NO3-.

Sex differences in gait utilization and energy metabolism during terrestrial locomotion in two varieties of chicken (Gallus gallus domesticus selected for different body size

Directory of Open Access Journals (Sweden)

Kayleigh A. Rose

2015-10-01

Full Text Available In leghorn chickens (Gallus gallus domesticus of standard breed (large and bantam (small varieties, artificial selection has led to females being permanently gravid and sexual selection has led to male-biased size dimorphism. Using respirometry, videography and morphological measurements, sex and variety differences in metabolic cost of locomotion, gait utilisation and maximum sustainable speed (Umax were investigated during treadmill locomotion. Males were capable of greater Umax than females and used a grounded running gait at high speeds, which was only observed in a few bantam females and no standard breed females. Body mass accounted for variation in the incremental increase in metabolic power with speed between the varieties, but not the sexes. For the first time in an avian species, a greater mass-specific incremental cost of locomotion, and minimum measured cost of transport (CoTmin were found in males than in females. Furthermore, in both varieties, the female CoTmin was lower than predicted from interspecific allometry. Even when compared at equivalent speeds (using Froude number, CoT decreased more rapidly in females than in males. These trends were common to both varieties despite a more upright limb in females than in males in the standard breed, and a lack of dimorphism in posture in the bantam variety. Females may possess compensatory adaptations for metabolic efficiency during gravidity (e.g. in muscle specialization/posture/kinematics. Furthermore, the elevated power at faster speeds in males may be linked to their muscle properties being suited to inter-male aggressive combat.

Uptake and loss of dissolved zinc by the stickleback gasterosteus Aculeatus l. [Zinc 65

Energy Technology Data Exchange (ETDEWEB)

Matthiessen, P.; Brafield, A.E.

1977-01-01

Uptake and loss by sticklebacks of both stable zinc and /sup 65/Zn in hard and soft water were studied for periods up to 400 h. In calcium-free water, the zinc uptake curve is approximately asymptotic over a period of 24 h, while in hard water internal Zn levels dropped at 24 h. Over 5 h, fish in hard tapwater absorb about 3 to 5 times more Zn than those in calcium-free water. There is positive linear correlation between log Zn uptake and log wet weight of fish. Whole-body concentration factors (c.f.) at 16 h reach a maximum of 12.2 (mean = 2.9), highest concentrations of Zn being found in the gills (mean c.f. = 5.1), and lowest concentrations in the gonads (mean c.f. = 0.8). Over longer periods (400 h), internal stable zinc levels of fish exposed to 1 and 4 ppM Zn/sup +2/ remain little higher than controls (max. 28%) /sup 65/Zn efflux in zinc-free water falls to zero after 5 h, more zinc (78%) being lost after uptake in tapwater than in calcium-free water (56%).

Prognostic impact of initial maximum standardized uptake value of 18F-FDG PET/CT on treatment response in patients with metastatic lung adenocarcinoma treated with erlotinib

Directory of Open Access Journals (Sweden)

Kus T

2015-12-01

Full Text Available Tulay Kus,1 Gokmen Aktas,1 Alper Sevinc,1 Mehmet Emin Kalender,1 Mustafa Yilmaz,2 Seval Kul,3 Serdar Oztuzcu,4 Cemil Oktay,5 Celaletdin Camci1 1Department of Internal Medicine, Division of Medical Oncology, Gaziantep Oncology Hospital, 2Department of Nuclear Medicine, 3Department of Biostatistics, Faculty of Medicine, 4Department of Medical Biology, Faculty of Medicine, University of Gaziantep, Gaziantep, 5Department of Radiology, Faculty of Medicine, University of Akdeniz, Antalya, Turkey Purpose: To investigate whether the initial maximum standardized uptake value (SUVmax on fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT has a prognostic significance in metastatic lung adenocarcinoma.Patients and methods: Sixty patients (24 females, mean age: 57.9±12 years with metastatic stage lung adenocarcinoma who used erlotinib and underwent 18F-FDG PET/CT at the time of diagnosis between May 2010 and May 2014 were enrolled in this retrospective study. The patients were stratified according to the median SUVmax value, which was found as 11. Progression-free survival (PFS rates for 3, 6, and 12 months were examined for SUVmax values and epidermal growth factor receptor (EGFR mutation status.Results: The number of EGFR-sensitizing mutation positive/negative/unknown was 26/17/17, respectively, and the number of patients using erlotinib at first-line, second-line, and third-line therapy was 15, 31, and 14 consecutively. The PFS rates of EGFR mutation positive, negative, and unknown patients for 3 months were 73.1%, 35.3%, and 41.2% (P=0.026, odds ratio [OR]=4.39; 95% confidence interval [CI]: 1.45–13.26, respectively. The PFS rates of EGFR positive, negative, and unknown patients for 6 months were 50%, 29.4%, and 29.4% (P=0.267, OR: 2.4; 95% CI: 0.82–6.96, respectively. The PFS rates of EGFR positive, negative, and unknown patients for 12 months were 42.3%, 29.4%, 23.5% (P=0.408, OR: 2.0; 95% CI: 0.42�

Differences in root uptake of radiocaesium by 30 plant taxa

Energy Technology Data Exchange (ETDEWEB)

Broadley, M R; Willey, N J [University of the West of England, Bristol (United Kingdom). Faculty of Applied Sciences

1998-12-31

The concentration of Cs was measured in the shoots of 30 taxa of plants after exposing the roots for 6 h to 0.1 {mu}g radiolabelled Cs g{sup -1} soil. There were maximum differences between Chenopodium quinoa and Koeleria macrantha of 20-fold in Cs concentration and 100-fold in total Cs accumulated. There was a weak relationship between Rb(K) and Cs concentration across the 30 taxa, but a strong relationship within the Gramineae and Chenopodiaceae. Taxa in the Chenopodiaceae discriminated approximately nine times less between Rb and Cs during uptake than did those in the Gramineae. The lowest Cs concentrations occurred in slow growing Gramineae and the highest in fast growing Chenopodiaceae. If radiocaesium uptake by the Chenopodiaceae during chronic exposures shows similar patterns to those reported here after acute exposure, then the food contamination implications and the potential for phytoremediation of radiocaesium contaminated soils using plants in this family may be worth investigating. (author).

Differences in root uptake of radiocaesium by 30 plant taxa

International Nuclear Information System (INIS)

Broadley, M.R.; Willey, N.J.

1997-01-01

The concentration of Cs was measured in the shoots of 30 taxa of plants after exposing the roots for 6 h to 0.1 μg radiolabelled Cs g -1 soil. There were maximum differences between Chenopodium quinoa and Koeleria macrantha of 20-fold in Cs concentration and 100-fold in total Cs accumulated. There was a weak relationship between Rb(K) and Cs concentration across the 30 taxa, but a strong relationship within the Gramineae and Chenopodiaceae. Taxa in the Chenopodiaceae discriminated approximately nine times less between Rb and Cs during uptake than did those in the Gramineae. The lowest Cs concentrations occurred in slow growing Gramineae and the highest in fast growing Chenopodiaceae. If radiocaesium uptake by the Chenopodiaceae during chronic exposures shows similar patterns to those reported here after acute exposure, then the food contamination implications and the potential for phytoremediation of radiocaesium contaminated soils using plants in this family may be worth investigating. (author)

Differences in root uptake of radiocaesium by 30 plant taxa

Energy Technology Data Exchange (ETDEWEB)

Broadley, M.R.; Willey, N.J. [University of the West of England, Bristol (United Kingdom). Faculty of Applied Sciences

1997-12-31

The concentration of Cs was measured in the shoots of 30 taxa of plants after exposing the roots for 6 h to 0.1 {mu}g radiolabelled Cs g{sup -1} soil. There were maximum differences between Chenopodium quinoa and Koeleria macrantha of 20-fold in Cs concentration and 100-fold in total Cs accumulated. There was a weak relationship between Rb(K) and Cs concentration across the 30 taxa, but a strong relationship within the Gramineae and Chenopodiaceae. Taxa in the Chenopodiaceae discriminated approximately nine times less between Rb and Cs during uptake than did those in the Gramineae. The lowest Cs concentrations occurred in slow growing Gramineae and the highest in fast growing Chenopodiaceae. If radiocaesium uptake by the Chenopodiaceae during chronic exposures shows similar patterns to those reported here after acute exposure, then the food contamination implications and the potential for phytoremediation of radiocaesium contaminated soils using plants in this family may be worth investigating. (author).

Colonic uptake patterns of F-18-FDG PET in asymptomatic adults: comparison with colonoscopic findings

International Nuclear Information System (INIS)

Pai, Moon Sun; Cho, Yoo Kyung; Jung, Sung Ae; Shim, Ki Nam; Lee, Hong Soo

2005-01-01

Physiologic intestinal FDG uptake is frequently observed in asymptomatic individuals for cancer screening FDG PET. Colonic FDG accumulation is a well-known confusing findings that interfere true cancer detection or cause false positive. The aim of this study was to evaluate the pattern and intensity of colonic uptake in whole body FDG PET in asymptomatic healthy adults and to correlate them with colonoscopic findings. We reviewed retrospectively 64 subjects (age: 27-87, M:F=31:33) who underwent both FDG PET and colonoscopy for cancer screening. FDG uptake patterns were classified as focal, segmental and diffuse. Maximum SUV were measured. The PET results were compared with colonoscopic and histologic findings. In 13 patients FDG bowel uptake was interpreted as focal, in 17 patients as segmental and in 34 patients as diffuse uptake. Six adenomas (17.6%, average diameter=5.0 mm) were found in diffuse pattern, 7 adenomas (41.1%, 5.6 mm) in segmental and 4 adenomas and 1 adenocarcinoma (38.5%, 16.4 mm) in focal uptake pattern. In patients with focal uptake, four were non-adenomatous pathologic lesions (30.8%, 2 intestinal tuberculosis, 2 mucosal ulcer). There is no difference of mean SUV between patients with adenoma and with negative colonoscopic results in each group of intestinal FDG pattern (Diffuse: 1.7 ± 0.1 vs 1.9 ± 0.5, Segmental: 4.8 ± 3.6 vs 4.2 ± 1.2, Focal: 6.5 ± 4.7 vs 3.5 ± 1.3). Large adenomas (>1 cm) can be detected more in the focal uptake pattern (4 out of 5) rather than in segmental (1 out of 7) or diffuse uptake (none) and had higher SUV (6.3 ± 4.8) than small adenomas (3.5 ± 3.0)(statistically insignificant). Focal FDG uptake is associated more often with large adenoma and other pathologic findings in colonoscopy. Segmental uptake cannot discriminate presence of adenoma from negative results, while diffuse pattern may have more chance to be normal

Thyroid Scan and Uptake

Medline Plus

Full Text Available ... for a thyroid scan is 30 minutes or less. Thyroid Uptake You will be given radioactive iodine (I-123 or I-131) in liquid or capsule form to swallow. The thyroid uptake will begin several hours to 24 hours later. Often, two separate uptake ...

Model analysis of the influence of gas diffusivity in soil on CO and H2 uptake

International Nuclear Information System (INIS)

Yonemura, S.; Yokozawa, M.; Kawashima, S.; Tsuruta, H.

2000-01-01

CO and H 2 uptake by soil was studied as a diffusion process. A diffusion model was used to determine how the surface fluxes (net deposition velocities) were controlled by in-situ microbial uptake rates and soil gas diffusivity calculated from the 3-phase system (solid, liquid, gas) in the soil. Analytical solutions of the diffusion model assuming vertical uniformity of soil properties showed that physical properties such as air-filled porosity and soil gas diffusivity were more important in the uptake process than in the emission process. To incorporate the distribution of in-situ microbial uptake, we used a 2-layer model incorporating 'a microbiologically inactive layer and an active layer' as suggested from experimental results. By numerical simulation using the 2-layer model, we estimated the effect of several factors on deposition velocities. The variations in soil gas diffusivity due to physical properties, i.e., soil moisture and air-filled porosity, as well as to the depth of the inactive layer and in-situ microbial uptake, were found to be important in controlling deposition velocities. This result shows that the diffusion process in soil is critically important for CO and H 2 uptake by soil, at least in soils with higher in-situ uptake rates and/or with large variation in soil moisture. Similar uptake rates and the difference in deposition velocity between CO and H 2 may be attributable to differences in CO and H 2 molecular diffusivity. The inactive layer is resistant to diffusion and creates uptake limits in CO and H 2 by soil. The coupling of high temperature and a thick inactive layer, common in arid soils, markedly lowers net CO deposition velocity. The temperature for maximum uptake of CO changes with depth of the inactive layer

Comparison of arsenic uptake ability of barnyard grass and rice species for arsenic phytoremediation.

Science.gov (United States)

Sultana, Razia; Kobayashi, Katsuichiro; Kim, Ki-Hyun

2015-01-01

In this research, the relative performance in arsenic (As) remediation was evaluated among some barnyard grass and rice species under hydroponic conditions. To this end, four barnyard grass varieties and two rice species were selected and tested for their remediation potential of arsenic. The plants were grown for 2 weeks in As-rich solutions up to 10 mg As L(-1) to measure their tolerance to As and their uptake capabilities. Among the varieties of plants tested in all treatment types, BR-29 rice absorbed the highest amount of As in the root, while Nipponbare translocated the maximum amount of As in the shoot. Himetainubie barnyard grass produced the highest biomass, irrespective of the quantity of As in the solution. In all As-treated solutions, the maximum uptake of As was found in BR-29 followed by Choto shama and Himetainubie. In contrast, while the bioaccumulation factor was found to be the highest in Nipponbare followed by BR-29 and Himetainubie. The results suggest that both Choto shama and Himetainubie barnyard grass varieties should exhibit a great potential for As removal, while BR-29 and Nipponbare rice species are the best option for arsenic phytoremediation.

Hydraulic Limits on Maximum Plant Transpiration

Science.gov (United States)

Manzoni, S.; Vico, G.; Katul, G. G.; Palmroth, S.; Jackson, R. B.; Porporato, A. M.

2011-12-01

Photosynthesis occurs at the expense of water losses through transpiration. As a consequence of this basic carbon-water interaction at the leaf level, plant growth and ecosystem carbon exchanges are tightly coupled to transpiration. In this contribution, the hydraulic constraints that limit transpiration rates under well-watered conditions are examined across plant functional types and climates. The potential water flow through plants is proportional to both xylem hydraulic conductivity (which depends on plant carbon economy) and the difference in water potential between the soil and the atmosphere (the driving force that pulls water from the soil). Differently from previous works, we study how this potential flux changes with the amplitude of the driving force (i.e., we focus on xylem properties and not on stomatal regulation). Xylem hydraulic conductivity decreases as the driving force increases due to cavitation of the tissues. As a result of this negative feedback, more negative leaf (and xylem) water potentials would provide a stronger driving force for water transport, while at the same time limiting xylem hydraulic conductivity due to cavitation. Here, the leaf water potential value that allows an optimum balance between driving force and xylem conductivity is quantified, thus defining the maximum transpiration rate that can be sustained by the soil-to-leaf hydraulic system. To apply the proposed framework at the global scale, a novel database of xylem conductivity and cavitation vulnerability across plant types and biomes is developed. Conductivity and water potential at 50% cavitation are shown to be complementary (in particular between angiosperms and conifers), suggesting a tradeoff between transport efficiency and hydraulic safety. Plants from warmer and drier biomes tend to achieve larger maximum transpiration than plants growing in environments with lower atmospheric water demand. The predicted maximum transpiration and the corresponding leaf water

The relation between respiratory motion artifact correction and lung standardized uptake value

International Nuclear Information System (INIS)

Yin Lijie; Liu Xiaojian; Liu Jie; Xu Rui; Yan Jue

2014-01-01

PET/CT is playing an important role in disease diagnosis and therapeutic evaluation. But the respiratory motion artifact may bring trouble in diagnosis and therapy. There are many methods to correct the respiratory motion artifact. Respiratory gated PET/CT is applied most extensively of them. Using respiratory gated PET/CT to correct respiratory motion artifact can increase the maximum standardized uptake value of lung lesion obviously, thereby improving the quality of image and accuracy of diagnosis. (authors)

Uptake of nuclides by plants

International Nuclear Information System (INIS)

Greger, Maria

2004-04-01

This review on plant uptake of elements has been prepared to demonstrate how plants take up different elements. The work discusses the nutrient elements, as well as the general uptake and translocation in plants, both via roots and by foliar absorption. Knowledge of the uptake by the various elements within the periodic system is then reviewed. The work also discusses transfer factors (TF) as well as difficulties using TF to understand the uptake by plants. The review also focuses on species differences. Knowledge necessary to understand and calculate plant influence on radionuclide recirculation in the environment is discussed, in which the plant uptake of a specific nuclide and the fate of that nuclide in the plant must be understood. Plants themselves determine the uptake, the soil/sediment determines the availability of the nuclides and the nuclides themselves can interact with each other, which also influences the uptake. Consequently, it is not possible to predict the nuclide uptake in plants by only analysing the nuclide concentration of the soil/substrate

Uptake of nuclides by plants

Energy Technology Data Exchange (ETDEWEB)

Greger, Maria [Stockholm Univ. (Sweden). Dept. of Botany

2004-04-01

This review on plant uptake of elements has been prepared to demonstrate how plants take up different elements. The work discusses the nutrient elements, as well as the general uptake and translocation in plants, both via roots and by foliar absorption. Knowledge of the uptake by the various elements within the periodic system is then reviewed. The work also discusses transfer factors (TF) as well as difficulties using TF to understand the uptake by plants. The review also focuses on species differences. Knowledge necessary to understand and calculate plant influence on radionuclide recirculation in the environment is discussed, in which the plant uptake of a specific nuclide and the fate of that nuclide in the plant must be understood. Plants themselves determine the uptake, the soil/sediment determines the availability of the nuclides and the nuclides themselves can interact with each other, which also influences the uptake. Consequently, it is not possible to predict the nuclide uptake in plants by only analysing the nuclide concentration of the soil/substrate.

Effects of pH on the growth and NH4-N uptake of Skeletonema costatum and Nitzschia closterium.

Science.gov (United States)

Gu, Xingyan; Li, Keqiang; Pang, Kai; Ma, Yunpeng; Wang, Xiulin

2017-11-30

Ocean acidification (OA) and eutrophication intensifies in coastal sea under anthropogenic impact. OA coupled with the NH 4 -N source effect in coastal water is likely to affect the planktonic ecosystem. In this work, Skeletonema costatum and Nitzschia closterium were chosen as typical species of diatom in Chinese coastal ecosystems to test the potential effect of OA and NH 4 -N. Results showed that the growth and NH 4 -N uptake of S. costatum and N. closterium were significantly inhibited by pH decline. The maximum uptake rate is higher than the maximum growth rate, implying that NH 4 -N was assimilated faster for S. costatum and N. closterium with decreasing pH. Therefore, the inhibition rate of the growth of the two diatoms by the coupling effect of OA and eutrophication (pH7.45) is higher that than in the coastal sea by the end of the 21st century (pH7.71). Copyright © 2017 Elsevier Ltd. All rights reserved.

Clinical Significance of Incidental Focal 18F-FDG Uptake in the Spinal Cord of Patients with Cancer.

Science.gov (United States)

Lim, Chae Hong; Hyun, Seung Hyup; Moon, Seung Hwan; Cho, Young Seok; Choe, Yearn Seong; Lee, Kyung-Han; Kim, Byung-Tae; Choi, Joon Young

2017-09-01

We investigated the incidence, location, and clinical significance of focal 18 F-FDG uptake of the spinal cord in patients with cancer. We reviewed the medical records of 22,937 consecutive adult patients with known or suspicious malignancy who underwent 18 F-FDG PET/CT. PET/CT scans with incidental focal spinal cord uptake were selected and retrospectively reviewed to determine the presence, location, number, and maximum standardized uptake value (SUV max ) of any focal hypermetabolic lesions of the spinal cord. In subjects with focal spinal uptake, clinical characteristics and clinical follow-up results, including follow-up PET/CT, were reviewed. Incidental focal spinal cord uptake was observed in 69 of 22,937 adult patients (incidence = 0.3%; M:F = 31:38; age, 55.8 ± 14.7 years). Seventy-eight focal hypermetabolic lesions on spinal cord in the PET/CT scans of the 69 study subjects were analyzed. The most common sites of focal spinal cord uptake were the T12 vertebra (47/78; 60.3%) and L1 vertebra (20/78; 25.6%). Multifocal cord uptake was found in 8 of 69 patients (11.6%). The average SUV max for cord uptake was 2.5 ± 0.5 (range, 1.4∼3.9). There was no clinical or imaging evidence of abnormalities in the spinal cord, both at the time of PET/CT and during clinical follow-up. Although incidental focal 18 F-FDG uptake of the spinal cord is rare in patients with cancer, it may be physiological or benign, but it should not be considered as malignant involvement. Common sites for the uptake were in the T12 and L1 spine levels.

Cadmium uptake capacity of an indigenous cyanobacterial strain, Nostoc entophytum ISC32: new insight into metal uptake in microgravity-simulating conditions.

Science.gov (United States)

Alidoust, Leila; Soltani, Neda; Modiri, Sima; Haghighi, Omid; Azarivand, Aisan; Khajeh, Khosro; Shahbani Zahiri, Hossein; Vali, Hojatollah; Akbari Noghabi, Kambiz

2016-02-01

Among nine cyanobacterial strains isolated from oil-contaminated regions in southern Iran, an isolate with maximum cadmium uptake capacity was selected and identified on the basis of analysis of morphological criteria and 16S rRNA gene sequence similarity as Nostoc entophytum (with 99% similarity). The isolate was tentatively designated N. entophytum ISC32. The phylogenetic affiliation of the isolates was determined on the basis of their 16S rRNA gene sequence. The maximum amount of Cd(II) adsorbed by strain ISC32 was 302.91 mg g(-1) from an initial exposure to a solution with a Cd(II) concentration of 150 mg l(-1). The cadmium uptake by metabolically active cells of cyanobacterial strain N. entophytum ISC32, retained in a clinostat for 6 days to simulate microgravity conditions, was examined and compared with that of ground control samples. N. entophytum ISC32 under the influence of microgravity was able to take up cadmium at amounts up to 29% higher than those of controls. The activity of antioxidant enzymes including catalase and peroxidase was increased in strain ISC32 exposed to microgravity conditions in a clinostat for 6 days, as catalase activity of the cells was more than three times higher than that of controls. The activity of the peroxidase enzyme increased by 36% compared with that of the controls. Membrane lipid peroxidation was also increased in the cells retained under microgravity conditions, up to 2.89-fold higher than in non-treated cells. Images obtained using scanning electron microscopy showed that cyanobacterial cells form continuous filaments which are drawn at certain levels, while the cells placed in a clinostat appeared as round-shaped, accumulated together and distorted to some extent.

Tc-99m-DMSA renal uptake rate and renal volume of elderly persons

International Nuclear Information System (INIS)

Ohishi, Yukihiko; Machida, Toyohei; Kido, Akira

1987-01-01

Renal function of erderly persons was evaluated by the radionuclide renal function test based on the renal uptake rate and the renal volume determined by Tc-99m-DMSA transectional tomographic images using single photon emission computed tomography (SPECT). Forty-three erderly cases (13 healthy persons and 30 patients with various types of renal disorders) aged between 60 and 87 on an average of 70 were studied and compared with results obtained from 20 healthy adults (18 - 45 years old). Renal volume was calculated from the summation of voxels in the region districted by equi-count threshold level (percentage to maximum count) on each section of the SPECT image. Attenuation correction was made by GE-STAR protocol utilizing Sorrenson's precorrection method. The renal uptake rate was expressed as a percentage of the total radioactivity detected within the renal volume, against an amount of dose injected. In the 26 kidneys of 13 healthy elderly persons, Tc-99m-DMSA renal uptake was 23 ± 5 %, which was significantly lower (p < 0.01) than that of healthy adults being 27 ± 2 %. A correlation coefficient between renal volume and uptake of 79 kidneys of 43 elderly persons was 0.5081 (p < 0.01). Creatinine clearance (Ccr) was better correlated with the total renal uptake (r = 0.6471, p < 0.01) than with the total renal volume (r = 0.3592, p < 0.01). This method is considered to be useful for clinical purpose as a test of renal function for elderly persons since it requires neither blood nor urine samples. (author)

Correlation of primary tumor FDG uptake with histopathologic features of advanced gastric cancer

International Nuclear Information System (INIS)

Kim, Hae Won; Won, Kyoung Sook; Song, Bong Il; Kang, Yu Na

2015-01-01

Histopathologic features could affect the FDG uptake of primary gastric cancer and detection rate on FDG PET/CT. The aim of this study was to evaluate the FDG uptake of primary gastric cancer by correlating it with the histopathologic features of the tumors. Fifty patients with locally advanced gastric adenocarcinoma who were referred for preoperative FDG-PET/CT scans were enrolled in this study. The detection rate of PET/CT and maximum standardized uptake values (SUV max ) of the primary tumor were compared using the WHO, Lauren, Ming and Borrmann classifications and tumor size and location. In 45 of the 50 patients (90 %), the primary gastric tumors were detected by FDG PET/CT. On comparison using the WHO classification, the detection rate and SUV max of the tubular type were significantly higher than those of the poorly cohesive type. On comparison using the Lauren and Ming classifications, the SUV maxs of the intestinal type and expanding type were significantly higher than those of the diffuse and infiltrative type, respectively. On comparison using the Borrmann classification and tumor size and location, there was no significant difference in the detection rate and SUV max of primary gastric tumors. This study demonstrates that the poorly cohesive type according to the WHO classification, diffuse type according to the Lauren classification and infiltrative type according to the Ming classification have low FDG uptake in patients with locally advanced gastric carcinoma. Understanding the relationship between primary tumor FDG uptake and histopathologic features would be helpful in detecting the primary tumor by FDG PET/CT in patients with gastric cancer

Diselenolane-mediated cellular uptake.

Science.gov (United States)

Chuard, Nicolas; Poblador-Bahamonde, Amalia I; Zong, Lili; Bartolami, Eline; Hildebrandt, Jana; Weigand, Wolfgang; Sakai, Naomi; Matile, Stefan

2018-02-21

The emerging power of thiol-mediated uptake with strained disulfides called for a move from sulfur to selenium. We report that according to results with fluorescent model substrates, cellular uptake with 1,2-diselenolanes exceeds uptake with 1,2-dithiolanes and epidithiodiketopiperazines with regard to efficiency as well as intracellular localization. The diselenide analog of lipoic acid performs best. This 1,2-diselenolane delivers fluorophores efficiently to the cytosol of HeLa Kyoto cells, without detectable endosomal capture as with 1,2-dithiolanes or dominant escape into the nucleus as with epidithiodiketopiperazines. Diselenolane-mediated cytosolic delivery is non-toxic (MTT assay), sensitive to temperature but insensitive to inhibitors of endocytosis (chlorpromazine, methyl-β-cyclodextrin, wortmannin, cytochalasin B) and conventional thiol-mediated uptake (Ellman's reagent), and to serum. Selenophilicity, the extreme CSeSeC dihedral angle of 0° and the high but different acidity of primary and secondary selenols might all contribute to uptake. Thiol-exchange affinity chromatography is introduced as operational mimic of thiol-mediated uptake that provides, in combination with rate enhancement of DTT oxidation, direct experimental evidence for existence and nature of the involved selenosulfides.

Modelling and Evaluation of Non-Linear Rootwater Uptake for Winter Cropping of Wheat and Berseem

Science.gov (United States)

GS, K.; Prasad, K. S. H.

2017-12-01

The plant water uptake is significant for study to monitor the irrigation supplied to the plant. The Richards equation has been the key governing equation to quantify the root water uptake in the vadose zone and it takes all the sources and sink terms into consideration. The β parameter or the non linearity parameter is used in this modeling to bring the non linearity in the plant root water uptake. The soil parameters are obtained by experimentation and are employed in the Van-Genuchten equation for soil moisture study. Field experiments were carried out at Civil Engineering Department IIT Roorkee, Uttarakhand, India, during the winter season of 2013 and 2014 for berseem and 2016 for wheat as per the local cropping practices. Drainage type lysimeters were installed to study the soil water balance. Soil moisture was monitored using profile probe. Precipitation and all meteorological data were obtained from the nearby gauges located at the National Institute of Hydrology, Roorkee.The moisture data and the deep percolation data were collected on a daily basis and the irrigation supply was controlled and monitored to satisfy the moisture requirements of the crops respectively.In order to study the effect of water scarcity on the crops, the plot was divided and deficited irrigation was applied for the second cropping season for Berseem.The yields for both the seasons was also measured. The solution of Richards equation as applied to the moisture movement in the root zone was modeled. For estimation of root water uptake, the governing equation is the one-dimensional mixed form of Richards' equation is employed (Ji et al., 2007; Shankar et al., 2012).The sink term in the model accounts for the root water uptake, which is utilized by the plant for transpiration. Smaxor the maximum root water uptake for the root zone on a given day must be equal to the maximum transpiration on the corresponding day The model computed moisture content and pressure head is calibrated with

Diffuse and diffuse-plus-focal uptake in the thyroid gland identified by using FDG-PET. Prevalence of thyroid cancer and Hashimoto's thyroiditis

International Nuclear Information System (INIS)

Kurata, Seiji; Ishibashi, Masatoshi; Hiromatsu, Yuji; Kaida, Hayato; Miyake, Ikuyo; Uchida, Masafumi; Hayabuchi, Naofumi

2007-01-01

The objective of this study was to investigate and evaluate the prevalence of incidental thyroid diffuse and diffuse-plus-focal fluorine-18 fluorodeoxyglucose (FDG) uptake in healthy subjects who underwent cancer screening on positron emission tomography (PET) scan, and also to evaluate the prevalence of thyroid cancer and Hashimoto's thyroiditis. We carried out a retrospective review of 1626 subjects who underwent PET scanning at our institution. Diffuse uptake was defined as FDG uptake in the whole thyroid gland, whereas diffuse-plus-focal uptake was defined as a thyroid lesion with both diffuse uptake and focal FDG uptake. The maximum standardized uptake value of the thyroid lesions was recorded and reviewed. In each selected subject with positive thyroid FDG uptake, serum thyroid-stimulating hormone, thyroid hormone, and thyroid antibodies were measured. Fine needle aspiration cytology was performed on patients with a definite nodule using ultrasonography. Twenty-nine subjects (1.78%) were identified as having either diffuse FDG uptake (n=25, 1.53%) or diffuse-plus-focal FDG uptake (n=4, 0.24%). All subjects with diffuse FDG uptake were diagnosed as having Hashimoto's thyroiditis. In 1 of the 25 subjects with diffuse FDG uptake and two of the four with diffuse-plus-focal FDG uptake, histopathologic diagnosis showed papillary thyroid carcinoma associated with Hashimoto's thyroiditis. However, PET scan did not detect papillary carcinoma associated with Hashimoto's thyroiditis in one of the three subjects. Our results suggest that although diffuse FDG uptake usually indicates Hashimoto's thyroiditis, the risk of thyroid cancer must be recognized in both diffuse FDG uptake and diffuse-plus-focal FDG uptake on PET scan. (author)

Evaluation of the relationship between physiological FDG uptake in the heart and age, blood glucose level, fasting period, and hospitalization

International Nuclear Information System (INIS)

Kaneta, Tomohiro; Hakamatsuka, Takashi; Takanami, Kentaro

2006-01-01

Positron emission tomography (PET) with fluorodeoxyglucose (FDG) is widely used for evaluation of cancer and ischemic heart disease. Recently, increased myocardial FDG uptake has been reported to be related to some types of heart disease, such as sarcoidosis. However, the physiological increased FDG uptake in the heart often mimics the abnormal high uptake in these cases. In this study, we investigated the relationships between myocardial uptake and age, blood glucose level, fasting period, and hospitalization status (inpatient vs. outpatient). A total of 159 non-diabetic patients were enrolled in the present study. Patients were imaged on a PET/CT scanner, and a three-dimensional region of interest (ROI) was drawn on the fused PET/CT image to measure the maximum standardized uptake value (SUV max ) of the whole left ventricle. No significant relationships were observed between myocardial uptake and age or fasting period. Blood glucose level showed a significant relationship (p=0.025) with myocardial uptake, but the R-square was extremely small (r 2 =0.03). With an SUV max threshold of 3.0, there was no significant difference between inpatients and outpatients. However, outpatients showed a significantly higher frequency of myocardial uptake over SUV max of 5.0 (x 2 test: p=0.046). It is difficult to predict the degree of physiological uptake in the heart from data regarding age, fasting period, or blood glucose level. Outpatients tend to show higher myocardial uptake than inpatients, which may make it difficult to detect abnormally increased uptake in the heart. A long fasting period, such as overnight fasting, is an inadequate means to reduce the physiological uptake of FDG in the heart. (author)

Physiological and tumoral uptake of 68Ga-DOTATATE. Standardized uptake values and challenges in interpretation

International Nuclear Information System (INIS)

Kuyumcu, Serkan; Oezkan, Zeynep Goezde; Sanli, Yasemin; Yilmaz, Ebru; Mudun, Ayse; Adalet, Isik; Unal, Seher

2013-01-01

The objective of this study is to determine the range of standardized uptake value (SUV) max of 68Ga-DOTA-tyr3-octreotate (DOTATATE) in normal organs and tumoral lesions and establish uptake unrelated to neuroendocrine tumors (NET). One hundred and twenty patients (57 men, 63 women), who underwent 68 Ga-DOTATATE positron emission tomography (PET)/CT imaging in our institution were analyzed. Patients were indicated for 68 Ga-DOTATATE PET/CT imaging to detect primary tumor or metastasis of suspected or previously known NET, to determine somatostatin receptor (SSTR) positivity and to detect occult source of ectopic Cushing syndrome. Normal range of uptake was calculated for the organs that were proven to have no pathology by either conventional radiological imaging or clinical follow-up, using SUV max as a semiquantitative measure. Uptake and tumor to background (T/B) ratios of tumoral lesions in liver, pancreas, bone, brain and lymph nodes were calculated. Uptakes due to lesions unrelated to NET were also documented. Significant uptake was found in spleen, kidneys, adrenal glands, liver and pituitary gland with mean SUV max of 24.67, 14.30, 13.73, 9.12 and 9.74 respectively. Uptake was measured separately for the pancreatic head and body separately, however, besides a slightly heterogeneous uptake; the difference was not statistically significant. Uptake in the tumoral lesions had high (T/B) ratios with mean SUV max of 28.72, 25.21, 18.28, 34.73 and 12.59 for liver, pancreas, bone, brain and lymph nodes, respectively. Incidental benign tumoral lesions were detected in 3 patients (2.5%) which were meningioma and fibrous dysplasia demonstrating significant and breast fibroadenoma demonstrating mild 68 Ga-DOTATATE uptake. Non-neoplastic processes were detected in 4 patients (14.1%), including postsurgical inflammation, reactive lymph nodes, arthritis and demonstrated faint to mild 68 Ga-DOTATATE uptake, with the exception of significant uptake in accessory spleen. 68 Ga

Strong association of epidermal growth factor receptor status with breast cancer FDG uptake

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Lee, Joohee; Moon, Seung Hwan; Hyun, Seung Hyup; Cho, Young Seok; Choi, Joon Young; Kim, Byung-Tae; Lee, Kyung-Han [Sungkyunkwan University School of Medicine, Department of Nuclear Medicine, Samsung Medical Center, Seoul (Korea, Republic of); Lee, Eun Jeong [Seoul Medical Center, Department of Nuclear Medicine, Seoul (Korea, Republic of); Kim, Seokhwi [Sungkyunkwan University School of Medicine, Department of Pathology, Samsung Medical Center, Seoul (Korea, Republic of)

2017-08-15

Imaging tumor FDG uptake could complement breast cancer biomarkers of risk and treatment response. Although breast cancer FDG uptake is reputedly influenced by major biomarker states, the role of epidermal growth factor receptor (EGFR) expression remains largely unexplored. This is a retrospective study that included 499 patients with primary breast cancer at initial presentation. Tumor FDG uptake was measured on pretreatment PET/CT as maximum standardized uptake value (SUVmax), and biomarkers were assessed by immunohistochemistry of tumor tissue. Regression analysis was performed for predictors of high tumor FDG uptake (SUVmax ≥ 8.6). SUVmax was higher in ER- (36.5%; 11.2 ± 6.0 vs. 8.3 ± 5.3), PR- (42.3%; 10.9 ± 6.0 vs. 8.2 ± 5.2), and triple-negative tumors (19.8%; 12.0 ± 6.9 vs. 8.7 ± 5.2; all p < 0.0001). EGFR expression (28.5%) was more frequent in ER-, PR-, triple-negative, cytokeratin 5/6 (CK5/6) + and mutant P53 (mP53) + tumors (all p < 0.0001). EGFR+ was associated with higher SUVmax among all tumors (11.9 ± 6.0 vs. 8.3 ± 5.3), ER- tumors (p < 0.0001), PR- and + tumors (p < 0.0001 and 0.027), hormone receptor- and + tumors (p < 0.0001 and 0.004), human epidermal growth factor receptor 2 (HER2)- and + tumors (p < 0.0001 and 0.006), non-triple negative tumors (p < 0.0001), CK5/6- and + tumors (p = 0.021 and <0.0001), and mP53- and + tumors (p < 0.0001 and 0.008). Tumors had high FDG uptake in 73.2% of EGFR+ and 40.6% of EGFR- tumors. On regression analysis, significant multivariate predictors of high tumor FDG uptake were large size, EGFR+ and CK5/6+ for the entire subjects, and EGFR+ and CK5/6+ for ER- and hormone receptor negative subgroups. High FDG uptake was able to sub-stratify EGFR+ tumors that were more likely to be ER- and CK5/6+, and EGFR- tumors more likely to be mP53 +. Primary breast tumor FDG uptake is strongly influenced by EGFR status beyond that by other major biomarkers including hormone receptor and HER2 status, and EGFR

Usefulness of lung and right ventricular thallium-201 uptake during single photon emission computed tomography in exercise testing of patients with coronary artery disease

International Nuclear Information System (INIS)

Matoh, Fumitaka; Tawarahara, Kei; Mikami, Naoshi

2005-01-01

Increased pulmonary or right ventricular 201 Tl uptake during the exercise test has been used as a marker of multivessel coronary artery disease. The most useful method for assessing the severity of coronary artery disease was evaluated among conventional evaluation of single photon emission computed tomography (SPECT), measurement of lung to heart uptake ratio (L/H), and right ventricular to left ventricular uptake ratio (RV/LV) on 201 Tl images during exercise testing. Regions-of-interest (4 x 4 pixels) were placed at the lung and the heart, and L/H was defined as mean lung uptake/mean heart uptake. Correspondingly, regions-of-interest (4 x 4 pixels) were placed at the RV and the LV, and RV/LV was defined as maximum RV uptake/maximum LV uptake. L/H and RV/LV on the initial image were analyzed in 216 patients (angiographically normal coronary arteries: 89, single-vessel disease: 82, multivessel disease: 45). The diagnostic value was evaluated using the receiver operating characteristic curve. All methods showed significantly higher values in patients with multivessel disease than in patients with no coronary artery disease or single-vessel disease. L/H was significantly higher in patients with prior myocardial infarction and RV/LV was significantly higher in patients without infarction. The sensitivity of only conventional SPECT evaluation for multivessel coronary artery disease was low (sensitivity 53%, specificity 94%). However, addition of evaluation of L/H and RV/LV to SPECT improved the sensitivity for multivessel coronary artery disease (sensitivity 93%, specificity 49%). The diagnostic sensitivity for multivessel coronary artery disease was improved by adding L/H and RV/LV to conventional evaluation of exercise 201 Tl SPECT. L/H and RV/LV during exercise 201 Tl imaging may provide additional information regarding the severity of coronary artery disease. (author)

Sorption-reduction coupled gold recovery process boosted by Pycnoporus sanguineus biomass: Uptake pattern and performance enhancement via biomass surface modification.

Science.gov (United States)

Shi, Chaohong; Zhu, Nengwu; Kang, Naixin; Wu, Pingxiao; Zhang, Xiaoping; Zhang, Yanhong

2017-09-01

Biorecovery is emerging as a promising process to retrieve gold from secondary resources. The present study aimed to explore the uptake pattern of Pycnoporus sanguineus biomass for gold, identify the effective functional groups in gold recovery process, and thus further intensify the process via microbial surface modification. Results showed that P. sanguineus biomass could effectively recover gold with the formation of highly crystal AuNPs without any exogeneous electron donor. Under the conditions of various initial gold concentrations (1.0, 2.0, and 3.0 mM), biomass dosage of 2.0 g/L, solution pH value of 4.0, and incubation temperature of 30°C, the uptake equilibrium established after 4, 8, and 12 h, respectively. The uptake process could be well described by pseudo-second order kinetics model (R 2  = 0.9988) and Langmuir isotherm model (R 2  = 0.9958). The maximum uptake capacity of P. sanguineus reached as high as 358.69 mg/g. Further analysis indicated that amino, carboxyl and hydroxyl groups positively contributed to the uptake process. Among them, amino group significantly favored the uptake of gold during recovery process. When P. sanguineus biomass was modified by introduction of amino group, the gold uptake process was successfully intensified by shortening the uptake period and enhancing the uptake capacity. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1314-1322, 2017. © 2017 American Institute of Chemical Engineers.

EFFECTS OF IMMOBILIZATION IN Ba-ALGINATE ON NITRILE-DEPENDENT OXYGEN UPTAKE RATES OF CANDIDA GUILLIERMONDII

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Dias João Carlos Teixeira

2001-01-01

Full Text Available Yeast cells immobilized by entrapment in Ba-alginate gel were investigated for growth pattern and respiratory activity. The oxygen uptake rates (OUR of cells entrapped in gels with 4% alginate were 5.2 and 23% lower than the OUR of 2% alginate and free cells, respectively. The mass-transfer resistance offered by the matrix and growth of the entrapped cells determine a gradient of nutrients throughout the gel which is responsible for both a lower specific growth rate of immobilized cells with respect to that of free ones, and a heterogeneous biomass distribution, with progressively increasing cellular density from the inside to the outside of the matrix. Gel-matrix polymer concentration affected the maximum oxygen uptake of immobilized growing yeast cells.

{sup 18}F-FDG uptake at the surgical margin after hepatic resection: Patterns of uptake and differential diagnosis

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Peungjesada, Silanath [University New Mexico, Department of Radiology, Albuquerque, NM (United States); Aloia, Thomas A. [University of Texas MD Anderson Cancer Center, Department of Surgical Oncology, Unit 444, Houston, TX (United States); Fox, Patricia [University of Texas MD Anderson Cancer Center, Department of Biostatistics, Unit 1411, Houston, TX (United States); Chasen, Beth [University of Texas MD Anderson Cancer Center, Department of Nuclear Medicine, Unit 1483, Houston, TX (United States); Shin, Sooyoung; Loyer, Evelyne M. [University of Texas MD Anderson Cancer Center, Department of Diagnostic Radiology, Unit 1473, Houston, TX (United States); Baiomy, Ali [Cairo University, National Cancer Center, Cairo (Egypt)

2015-08-15

To evaluate the patterns of {sup 18}F-FDG uptake at the surgical margin after hepatectomy to identify features that may differentiate benign and malignant uptake. Patients who had undergone a PET/CT after hepatectomy were identified. Delay between resection and PET/CT, presence of uptake at the surgical margin, pattern of uptake, and maximal standardized value were recorded. The PET/CT findings were correlated with contrast-enhanced CT or MRI. There were 26 patients with increased 18F-FDG uptake; uptake was diffuse in seven and focal in 19. Diffuse uptake was due to inflammation in all cases. Focal uptake was due to recurrence in 12 and inflammation in seven cases. Defining a focal pattern only as a positive for malignancy yielded 100 % sensitivity, 87 % specificity, 37 % false positive rate. As expected, SUV{sub max} was significantly higher for recurrence than inflammation, but did overlap. Contrast-enhanced CT allowed differentiation between malignant and benign uptake in all cases. F-FDG uptake after hepatectomy does not equate to recurrence and yields a high false positive rate. Diffuse uptake did not require additional evaluation in our sample. Focal uptake, however, may be due to recurrence; differentiating benign and malignant nodular uptake relies on optimal contrast-enhanced CT or MRI. (orig.)

Hepatic Pseudolymphoma with Fluorodeoxyglucose Uptake on Positron Emission Tomography

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Kazuhiro Suzumura

2017-12-01

Full Text Available A 69-year-old woman with chronic hepatitis B was admitted to our hospital with a hepatic tumor. The levels of 2 tumor markers, carcinoembryonic antigen and carbohydrate antigen 19-9, were slightly elevated; however, the α-fetoprotein and protein levels induced by vitamin K antagonist II were within the normal limits. Abdominal ultrasonography showed a well-defined peripheral hypoechoic mass that was isoechoic and homogeneous on the inside. Computed tomography showed a poorly enhanced tumor of 13 mm in diameter in the 5th segment of the liver. Fluorodeoxyglucose positron emission tomography showed a slight uptake (maximum standard uptake value 3.4 by the hepatic tumor. These findings suggested cholangiocellular carcinoma, and we performed anterior segmentectomy of the liver. A histopathological examination showed a hepatic pseudolymphoma. The patient’s postoperative course was uneventful, and she remains alive without recurrence 5 months after undergoing surgery. In most cases, hepatic pseudolymphoma is preoperatively diagnosed as a malignant tumor and a definite diagnosis is made after resection. It is therefore necessary to consider hepatic pseudolymphoma as a differential diagnosis in patients with hepatic tumors.

Uptake of Tyrosine Amino Acid on Nano-Graphene Oxide

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Hossam M. Nassef

2018-01-01

Full Text Available Graphene oxide (GO is emerging as a promising nanomaterial with potential application in the detection and analysis of amino acids, DNA, enzymes, and proteins in biological fluid samples. So, the reaction of GO with amino acids should be characterized and determined before using it in biosensing methods and devices. In this study, the reaction of tyrosine amino acid (Tyr with GO was characterized using FT-IR, UV-vis spectrophotometry, and scanning electron microscopy (SEM before its use. The optimum conditions for GO’s interaction with Tyr amino acid have been studied under variable conditions. The optimum conditions of pH, temperature, shaking time, and GO and tyrosine concentrations for the uptaking of tyrosine amino acid onto the GO’s surface from aqueous solution were determined. The SEM analysis showed that the GO supplied was in a particle size range between 5.4 and 8.1 nm. A pH of 8.4–9.4 at 25 °C and 5 min of shaking time were the optimum conditions for a maximum uptake of 1.4 μg/mL of tyrosine amino acid onto 0.2 mg/mL of GO.

Concurrent low brain and high liver uptake on FDG PET are associated with cardiovascular risk factors

International Nuclear Information System (INIS)

Nam, Hyun Yeol; Jun, Sung Min; Pak, Kyoung June; Kim, In Joo

2017-01-01

Concurrent low brain and high liver uptake are sometimes observed on fluorine-18-labeled fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET). We investigated the potential clinical significance of this uptake pattern related to metabolic syndrome (MS). We retrospectively reviewed data from 264 consecutive males who had undergone general health check-ups, including FDG PET/CT scans. After an overnight fast, the men had their peripheral blood drawn and the levels of various laboratory parameters measured; an FDG PET/CT scan was performed on the same day. We measured the maximum standardized uptake values of the brain and liver from regions of interest manually placed over the frontal cortex at the level of the centrum semiovale and the right lobe of the liver parenchyma, respectively. Fasting blood glucose (FBG; odds ratio [OR] = 1.063, p < 0.001) and glycated hemoglobin (HbA1c; OR = 3.634, p = 0.010) were the strongest predictive factors for low brain FDG uptake, whereas waist circumference (OR = 1.200, p < 0.001) and γ-glutamyl transpeptidase (OR = 1.012, p = 0.001) were the strongest predictive factors for high liver uptake. Eleven subjects (4.2%) showed concurrent low brain and high liver FDG uptake, and all but one of these subjects (90.9%) had MS. Systolic blood pressure, waist circumference, FBG, triglyceride, alanine aminotransferase, insulin resistance (measured by homeostasis model assessment), insulin, HbA1c, and body mass index were higher in subjects with this FDG uptake pattern than in those without (all, p < 0.001). Concurrent low brain and high liver FDG uptake were closely associated with MS. Moreover, subjects with this pattern had higher values for various cardiovascular risk factors than did those without

Concurrent low brain and high liver uptake on FDG PET are associated with cardiovascular risk factors

Energy Technology Data Exchange (ETDEWEB)

Nam, Hyun Yeol [Dept. of Nuclear Medicine, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon (Korea, Republic of); Jun, Sung Min [Dept. of Nuclear Medicine, Kosin University Gospel Hospital, Kosin University College of Medicine, Busan (Korea, Republic of); Pak, Kyoung June; Kim, In Joo [Dept. of Nuclear Medicine and Biomedical Research Institute, Pusan National University Hospital, Busan (Korea, Republic of)

2017-04-15

Concurrent low brain and high liver uptake are sometimes observed on fluorine-18-labeled fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET). We investigated the potential clinical significance of this uptake pattern related to metabolic syndrome (MS). We retrospectively reviewed data from 264 consecutive males who had undergone general health check-ups, including FDG PET/CT scans. After an overnight fast, the men had their peripheral blood drawn and the levels of various laboratory parameters measured; an FDG PET/CT scan was performed on the same day. We measured the maximum standardized uptake values of the brain and liver from regions of interest manually placed over the frontal cortex at the level of the centrum semiovale and the right lobe of the liver parenchyma, respectively. Fasting blood glucose (FBG; odds ratio [OR] = 1.063, p < 0.001) and glycated hemoglobin (HbA1c; OR = 3.634, p = 0.010) were the strongest predictive factors for low brain FDG uptake, whereas waist circumference (OR = 1.200, p < 0.001) and γ-glutamyl transpeptidase (OR = 1.012, p = 0.001) were the strongest predictive factors for high liver uptake. Eleven subjects (4.2%) showed concurrent low brain and high liver FDG uptake, and all but one of these subjects (90.9%) had MS. Systolic blood pressure, waist circumference, FBG, triglyceride, alanine aminotransferase, insulin resistance (measured by homeostasis model assessment), insulin, HbA1c, and body mass index were higher in subjects with this FDG uptake pattern than in those without (all, p < 0.001). Concurrent low brain and high liver FDG uptake were closely associated with MS. Moreover, subjects with this pattern had higher values for various cardiovascular risk factors than did those without.

Effect of MRI acoustic noise on cerebral fludeoxyglucose uptake in simultaneous MR-PET imaging.

Science.gov (United States)

Chonde, Daniel B; Abolmaali, Nasreddin; Arabasz, Grae; Guimaraes, Alexander R; Catana, Ciprian

2013-05-01

Integrated scanners capable of simultaneous positron emission tomography (PET) and magnetic resonance imaging (MRI) data acquisition are now available for human use. Although the scanners' manufacturers have made substantial efforts to understand and minimize the mutual electromagnetic interference between the 2 modalities, the potential physiological inference has not been evaluated. In this study, we have studied the influence of the acoustic noise produced by the magnetic resonance (MR) gradients on brain fludeoxyglucose (FDG) uptake in the Siemens MR-BrainPET prototype. Although particular attention was paid to the primary auditory cortex (PAC), a brain-wide analysis was also performed. The effects of the MR on the PET count rate and image quantification were first investigated in phantoms. Next, 10 healthy volunteers underwent 2 simultaneous FDG-PET/MR scans in the supine position with the FDG injection occurring inside the MR-BrainPET, alternating between a "quiet" (control) environment in which no MR sequences were run during the FDG uptake phase (the first 40 minutes after radiotracer administration) and a "noisy" (test) environment in which MR sequences were run for the entire time. Cortical and subcortical regions of interest were derived from the high-resolution morphological MR data using FreeSurfer. The changes in the FDG uptake in the FreeSurfer-derived regions of interest between the 2 conditions were analyzed from parametric and static PET images, and on a voxel-by-voxel basis using SPM8 and FreeSurfer. Only minimal to no electromagnetic interference was observed for most of the MR sequences tested, with a maximum drop in count rate of 1.5% and a maximum change in the measured activity of 1.1% in the corresponding images. The region of interest-based analysis showed statistically significant increases in the right PAC in both the parametric (9.13% [4.73%]) and static (4.18% [2.87%]) images. The SPM8 analysis showed no statistically significant

Effect of MRI Acoustic Noise on Cerebral FDG Uptake in Simultaneous MR-PET Imaging

Science.gov (United States)

Abolmaali, Nasreddin; Arabasz, Grae; Guimaraes, Alexander R.; Catana, Ciprian

2013-01-01

Integrated scanners capable of simultaneous PET and MRI data acquisition are now available for human use. Although the scanners’ manufacturers have made substantial efforts to understand and minimize the mutual electromagnetic interference between the two modalities, the potential physiological inference has not been evaluated. In this work, we have studied the influence of the acoustic noise produced by the MR gradients on brain FDG uptake in the Siemens MR-BrainPET prototype. While particular attention was paid to the primary auditory cortex (PAC), a brain-wide analysis was also performed. Methods The effects of the MR on the PET count rate and image quantification were first investigated in phantoms. Next, ten healthy volunteers underwent two simultaneous FDG-PET/MR scans in the supine position with the FDG injection occurring inside the MR-BrainPET, alternating between a “quiet” (control) environment in which no MR sequences were run during the FDG uptake phase (the first 40 minutes after radiotracer administration) and a “noisy” (test) case in which MR sequences were run for the entire time. Cortical and subcortical regions of interest (ROIs) were derived from the high-resolution morphological MR data using FreeSurfer. The changes in FDG uptake in the FreeSurfer-derived ROIs between the two conditions were analyzed from parametric and static PET images, and on a voxel-by-voxel basis using SPM8 and FreeSurfer. Results Only minimal to no electromagnetic interference was observed for most of the MR sequences tested, with a maximum drop in count rate of 1.5% and a maximum change in the measured activity of 1.1% in the corresponding images. The ROI-based analysis showed statistically significant increases in the right PAC in both the parametric (9.13±4.73%) and static (4.18±2.87%) images. SPM8 analysis showed no statistically significant clusters in any images when a p<0.05 (corrected) was used; however, a p<0.001 (uncorrected) resolved bilateral

Clinical significance of incidental focal "1"8F-FDG uptake in the spinal cord of patients with cancer

International Nuclear Information System (INIS)

Lim, Chae Hong; Hyun, Seung Hyup; Moon, Seung Hwan; Cho, Young Seok; Choe, Yearn Seong; Lee, Kyung Han; Kim, Byung Tae; Choi, Joon Young

2017-01-01

We investigated the incidence, location, and clinical significance of focal "1"8F-FDG uptake of the spinal cord in patients with cancer. We reviewed the medical records of 22,937 consecutive adult patients with known or suspicious malignancy who underwent "1"8F-FDG PET/CT. PET/CT scans with incidental focal spinal cord uptake were selected and retrospectively reviewed to determine the presence, location, number, and maximum standardized uptake value (SUV_m_a_x) of any focal hypermetabolic lesions of the spinal cord. In subjects with focal spinal uptake, clinical characteristics and clinical follow-up results, including follow-up PET/CT, were reviewed. Incidental focal spinal cord uptake was observed in 69 of 22,937 adult patients (incidence = 0.3%; M:F = 31:38; age, 55.8 ± 14.7 years). Seventy-eight focal hypermetabolic lesions on spinal cord in the PET/CT scans of the 69 study subjects were analyzed. The most common sites of focal spinal cord uptake were the T12 vertebra (47/78; 60.3%) and L1 vertebra (20/78; 25.6%). Multifocal cord uptake was found in 8 of 69 patients (11.6%). The average SUVmax for cord uptake was 2.5 ± 0.5 (range, 1.4∼3.9). There was no clinical or imaging evidence of abnormalities in the spinal cord, both at the time of PET/CT and during clinical follow-up. Although incidental focal "1"8F-FDG uptake of the spinal cord is rare in patients with cancer, it may be physiological or benign, but it should not be considered as malignant involvement. Common sites for the uptake were in the T12 and L1 spine levels

Clinical significance of incidental focal {sup 18}F-FDG uptake in the spinal cord of patients with cancer

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Lim, Chae Hong; Hyun, Seung Hyup; Moon, Seung Hwan; Cho, Young Seok; Choe, Yearn Seong; Lee, Kyung Han; Kim, Byung Tae; Choi, Joon Young [Dept. of Nuclear Medicine, Samsung Medical CenterSungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

2017-09-15

We investigated the incidence, location, and clinical significance of focal {sup 18}F-FDG uptake of the spinal cord in patients with cancer. We reviewed the medical records of 22,937 consecutive adult patients with known or suspicious malignancy who underwent {sup 18}F-FDG PET/CT. PET/CT scans with incidental focal spinal cord uptake were selected and retrospectively reviewed to determine the presence, location, number, and maximum standardized uptake value (SUV{sub max}) of any focal hypermetabolic lesions of the spinal cord. In subjects with focal spinal uptake, clinical characteristics and clinical follow-up results, including follow-up PET/CT, were reviewed. Incidental focal spinal cord uptake was observed in 69 of 22,937 adult patients (incidence = 0.3%; M:F = 31:38; age, 55.8 ± 14.7 years). Seventy-eight focal hypermetabolic lesions on spinal cord in the PET/CT scans of the 69 study subjects were analyzed. The most common sites of focal spinal cord uptake were the T12 vertebra (47/78; 60.3%) and L1 vertebra (20/78; 25.6%). Multifocal cord uptake was found in 8 of 69 patients (11.6%). The average SUVmax for cord uptake was 2.5 ± 0.5 (range, 1.4∼3.9). There was no clinical or imaging evidence of abnormalities in the spinal cord, both at the time of PET/CT and during clinical follow-up. Although incidental focal {sup 18}F-FDG uptake of the spinal cord is rare in patients with cancer, it may be physiological or benign, but it should not be considered as malignant involvement. Common sites for the uptake were in the T12 and L1 spine levels.

Hydraulic limits on maximum plant transpiration and the emergence of the safety-efficiency trade-off.

Science.gov (United States)

Manzoni, Stefano; Vico, Giulia; Katul, Gabriel; Palmroth, Sari; Jackson, Robert B; Porporato, Amilcare

2013-04-01

Soil and plant hydraulics constrain ecosystem productivity by setting physical limits to water transport and hence carbon uptake by leaves. While more negative xylem water potentials provide a larger driving force for water transport, they also cause cavitation that limits hydraulic conductivity. An optimum balance between driving force and cavitation occurs at intermediate water potentials, thus defining the maximum transpiration rate the xylem can sustain (denoted as E(max)). The presence of this maximum raises the question as to whether plants regulate transpiration through stomata to function near E(max). To address this question, we calculated E(max) across plant functional types and climates using a hydraulic model and a global database of plant hydraulic traits. The predicted E(max) compared well with measured peak transpiration across plant sizes and growth conditions (R = 0.86, P efficiency trade-off in plant xylem. Stomatal conductance allows maximum transpiration rates despite partial cavitation in the xylem thereby suggesting coordination between stomatal regulation and xylem hydraulic characteristics. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

Impact of second reminder invitation on uptake of screening and cancer detection in BreastCheck.

LENUS (Irish Health Repository)

Fleming, P

2012-01-01

This research aims to quantify the impact of reminder invitations on uptake and cancer detection in Ireland. Examination of BreastCheck\\'s clinical database (2000-2010) to determine number of women screened following first invitation and after reminder; comparison by age group and screening phase with outcomes of recall rate, cancer detection and true positive rates. Of 819,182 first invitations sent 448,974 (54.8%) women attended. 245,157 (66.2%) women attended after reminder invitations, increasing uptake by 29.9% to 694,131 (84.7%) and cancers detected by 1,550 (35%). Women awaiting a reminder were less likely recalled for assessment 9,555 (3.9%) than respondents to first invitation 2,887 (4.04%) (p=0.004). Younger, mainly initial women were more likely recalled for assessment after first invitation. There was no difference between cohorts for cancer detection rate or true positive rate. Reminders increased uptake, supporting international evidence. For programme efficiency attendance at first invitation is optimal. For maximum programme effectiveness attendance must be encouraged with reminders.

Uptake of radioactive strontium by fishes in relation to the calcium content of the water

International Nuclear Information System (INIS)

Chiosila, J.

1975-01-01

The study attempts to compare experimental results obtained with pseudorasbora parava with regard to 85 Sr uptake at various Ca concentrations of the water (4.20 and 50 mg/l Ca) and also to compare these results with natural conditions. The water was contaminated with 500 pCi/ml 85 SrCl 2 only at the onset of the experiments. Radiostrontium uptake is much higher with a very low calcium content of the water; maximum values are reached in about 10 days. - With low or optimum calcium contents of the water, the values are 3-5 times lower and are not reached until 30 days after radioactive contamination. The fish in this Danube water experiment took up somewhat less radioactivity than in an experiment with the same amounts of Ca and Mg in a control medium. The uptake of 85 Sr in fish in dependence of the Ca content of the water varies according to the formula F.C = 2.505 x Casup(-0.909), with Ca given in Mg/l. (orig.) [de

Comparison between FDG Uptake and Pathologic or Immunohistochemical Parametersin Pre-operative PET/CT Scan of Patient with Primary Colorectal Cancer

International Nuclear Information System (INIS)

Na, Sae Jung; Chung, Yong An; Maeng, Lee So; Kim, Ki Jun; Sohn, Kyung Myung; Kim, Sung Hoon; Sohn, Hyung Sun; Chung, Soo Kyo

2009-01-01

To evaluate the relationship between F-18 FDG uptake of tumor in PET/CT scan and pathological or immunohistochemial parameters of colorectal cancer. 147 colorectal cancer patients who underwent both pre-operative F-18 FDG PET/CT scan and surgery were included. In cases with perceptible FDG uptake in primary tumor, the maximum standardized uptake value (SUVmax) was calculated. The pathologic results such as site, size, depth of invasion (T stage), growth pattern, differentiation of primary tumor, lymph node metastasis and Dukes-Astler and Coller stage and immunohistochemical markers such as expression of EGFR, MLH1, MSH2 and Ki-67 index were reviewed. 146 out of 147 PET/CT scans with colorectal cancer showed perceptible focal FDG uptake. SUVmax showed mild positive linear correlation with size of primary tumor (r=0.277, p=0.001) and Ki-67 index (r=0.226, p=0.019). No significant difference in F-18 FDG uptake was found according to site, depth of invasion (T stage), growth pattern, differentiation of primary tumor, presence of lymph node metastasis, Dukes-Astler and Coller stage and expression of EGFR. The degree of F-18 FDG uptake in colorectal cancer was associated with the size and the degree of Ki-67 index of primary tumor. It could be thought that FDG uptake of primary tumor has a correlation with macroscopic and microscopic tumor growth

Bone uptake by di and tetraphosphonates labeled with Rhenium-188

International Nuclear Information System (INIS)

Faintuch, B.L.; Osso, J.A. Jr.; Muramoto, E.; Faintuch, S.

2002-01-01

MDP (methylenediphosphonate) and HEDP (hydroxyethylidenediphosphonate), both diphosphonates, and EDTMP (ethylenediamine tetramethylene phosphonic acid) a tetraphosphonate ligand, have been labeled with 188 Re for use in metastatic bone-pain palliation. The aim of this study was a comparison between the three complexes 188 Re-MDP, 188 Re-HEDP and 188 Re-EDTMP concerning the complexation conditions, in order to achieve maximum yield, stability and bone uptake. Methods: MDP was dissolved in water and HEDP and EDTMP were dissolved in NaOH 1N followed by decreasing pH with HCl 1N. To all mixtures stannous chloride and 188 ReO 4 were added in a nitrogen atmosphere. The preparations were heated in a boiling water bath for 15 min. The yields as well as the radiochemical stability were estimated by ITLC. Different concentrations of phosphonates and stannous chloride were evaluated. Biodistribution studies in swiss mice were done for the three 188 Re-phosphonates that presented the best radiochemical yield. Results: For 188 Re-MDP and 188 Re-HEDP the optimal ligand concentration for maximum complexation was 30 mg whereas for 188 Re-EDTMP, it was 40 mg. The best amount of SnCl 2 .2H 2 O was 2 mg/mL for MDP, 3 mg/mL for HEDP and 1 mg/mL for EDTMP. In these conditions the three complexes showed a complexation yield above 95%. All of them presented 4-hour radiochemical stability without the need for ascorbic acid solution, but for 24 hours this stability existed only in the presence of that substance otherwise re-oxidation of 188 Re occurred. All products showed a great uptake by the kidneys. 188 Re-EDTMP had the greatest uptake by the bone (3.13 ± 0.18% ID/g) followed by 188 Re-MDP (1.18 ± 0.05%ID/g) and 188 Re-HEDP (1.03 ± 0.12 %ID/g), 4 hour postinjection. 188 Re-EDTMP displayed a bone/muscle ratio of 28.5, 188 Re-MDP 4.9 and 188 Re-HEDP 4.9. Conclusion: 188 Re-EDTMP demonstrated the best potential as a radiopharmaceutical for bone cancer pain relief, encouraging further

New Synthesis of nZVI/C Composites as an Efficient Adsorbent for the Uptake of U(VI) from Aqueous Solutions.

Science.gov (United States)

Liu, Haibo; Li, Mengxue; Chen, Tianhu; Chen, Changlun; Alharbi, Njud S; Hayat, Tasawar; Chen, Dong; Zhang, Qiang; Sun, Yubing

2017-08-15

New nanoscale zerovalent iron/carbon (nZVI/C) composites were successfully prepared via heating natural hematite and pine sawdust at 800 °C under nitrogen conditions. Characterization by SEM, XRD, FTIR, and XPS analyses indicated that the as-prepared nZVI/C composites contained a large number of reactive sites. The lack of influence of the ionic strength revealed inner-sphere complexation dominated U(VI) uptake by the nZVI/C composites. Simultaneous adsorption and reduction were involved in the uptake process of U(VI) according to the results of XPS and XANES analyses. The presence of U-C/U-U shells demonstrated that innersphere complexation and surface coprecipitation dominated the U(VI) uptake at low and high pH conditions, respectively. The uptake behaviors of U(VI) by the nZVI/C composites were fitted well by surface complexation modeling with two weak and two strong sites. The maximum uptake capacity of U(VI) by the nZVI/C composites was 186.92 mg/g at pH 4.0 and 328 K. Additionally, the nZVI/C composites presented good recyclability and recoverability for U(VI) uptake in regeneration experiments. These observations indicated that the nZVI/C composites can be considered as potential adsorbents to remove radionuclides for environmental remediation.

Specific light uptake rates can enhance astaxanthin productivity in Haematococcus lacustris.

Science.gov (United States)

Lee, Ho-Sang; Kim, Z-Hun; Park, Hanwool; Lee, Choul-Gyun

2016-05-01

Lumostatic operation was applied for efficient astaxanthin production in autotrophic Haematococcus lacustris cultures using 0.4-L bubble column photobioreactors. The lumostatic operation in this study was performed with three different specific light uptake rates (q(e)) based on cell concentration, cell projection area, and fresh weight as one-, two- and three-dimensional characteristics values, respectively. The q(e) value from the cell concentration (q(e1D)) obtained was 13.5 × 10⁻⁸ μE cell⁻¹ s⁻¹, and the maximum astaxanthin concentration was increased to 150 % compared to that of a control with constant light intensity. The other optimum q e values by cell projection area (q(e2D)) and fresh weight (q( e3D)) were determined to be 195 μE m⁻² s⁻¹ and 10.5 μE g⁻¹ s⁻¹ for astaxanthin production, respectively. The maximum astaxanthin production from the lumostatic cultures using the parameters controlled by cell projection area (2D) and fresh weight (3D) also increased by 36 and 22% over that of the controls, respectively. When comparing the optimal q e values among the three different types, the lumostatic cultures using q(e) based on fresh weight showed the highest astaxanthin productivity (22.8 mg L⁻¹ day⁻¹), which was a higher level than previously reported. The lumostatic operations reported here demonstrated that more efficient and effective astaxanthin production was obtained by H. lacustris than providing a constant light intensity, regardless of which parameter is used to calculate the specific light uptake rate.

Thyroid Scan and Uptake

Medline Plus

Full Text Available ... for a thyroid scan is 30 minutes or less. Thyroid Uptake You will be given radioactive iodine ( ... for each thyroid uptake is five minutes or less. top of page What will I experience during ...

Thyroid Scan and Uptake

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Full Text Available ... Scan and Uptake Thyroid scan and uptake uses small amounts of radioactive materials called radiotracers, a special ... is a branch of medical imaging that uses small amounts of radioactive material to diagnose and determine ...

Thyroid Scan and Uptake

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Full Text Available ... uptake measurements are obtained at different times. For example, you may have uptake measurements at four to ... medicine procedures can be time consuming. It can take several hours to days for the radiotracer to ...

Thyroid Scan and Uptake

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Full Text Available ... known as a thyroid uptake. It is a measurement of thyroid function, but does not involve imaging. ... eating can affect the accuracy of the uptake measurement. Jewelry and other metallic accessories should be left ...

Thyroid Scan and Uptake

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Full Text Available ... Uptake? A thyroid scan is a type of nuclear medicine imaging. The radioactive iodine uptake test (RAIU) ... of thyroid function, but does not involve imaging. Nuclear medicine is a branch of medical imaging that ...

Circadian rhythm in ''1''5O-labeled water uptake manner of a soybean plant by PETIS (Positron Emitting Tracer Imaging System)

International Nuclear Information System (INIS)

Nakanishi, Tomoko M.; Yokota, Harumi; Tanoi, Keitaro; Furukawa, Jun; Ikeue, Natsuko; Ookuni, Yoko; Uchida, Hiroshi; Tsuji, Atsunori

2001-01-01

We present a circadian rhythm of water uptake manner in a soybean plant through realtime imaging of water, labeled with 15 O. Nitrogen gas was irradiated with deuterons accelerated by a cyclotron at Hamamatsu Photonics Co. to produce 15 O-labeled water. Then the 15 O-labeled water was supplied to a soybean plant from the root and the realtime water uptake amount was measured for 20 min by Positron Emitting Tracer Imaging System (PETIS). All the targeting positions for the measurements were stems, two points at an internode between root and the first leaves, between the first leaves and the first trifoliates and between the first trifoliates and the second trifoliates. The water uptake amount was gradually increased and showed its maximum at around 13:00, especially at the basal part of the stem. Then the water uptake activity was gradually decreased until 17:00. The water amount taken up by a plant at 13:00 was about 40% higher than that at 17:00. (author)

Thyroid Scan and Uptake

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Full Text Available ... radioactive iodine uptake test (RAIU) is also known as a thyroid uptake. It is a measurement of ... potential to identify disease in its earliest stages as well as a patient’s immediate response to therapeutic ...

RAPID NITRATE UPTAKE RATES AND LARGE SHORT-TERM STORAGE CAPACITIES MAY EXPLAIN WHY OPPORTUNISTIC GREEN MACROALGAE DOMINATE SHALLOW EUTROPHIC ESTUARIES1.

Science.gov (United States)

Kennison, Rachel L; Kamer, Krista; Fong, Peggy

2011-06-01

We quantified the effects of initial macroalgal tissue nitrogen (N) status (depleted and enriched) and varying pulses of nitrate (NO 3 - ) concentration on uptake and storage of nitrogen in Ulva intestinalis L. and Ulva expansa (Setch.) Setch. et N. L. Gardner using mesocosms modeling shallow coastal estuaries in Mediterranean climates. Uptake of NO 3 - (μmol · g dry weight [dwt] -1  · h -1 ) was measured as loss from the water after 1, 2, 4, 8, 12, and 24 h and storage as total tissue nitrogen (% dwt) and nitrate (ppm). Both species of algae exhibited a high affinity for NO 3 - across all N pulses and initial tissue contents. There was greater NO 3 - removal from the water for depleted than enriched algae across all time intervals. In the low-N-pulse treatment, U. intestinalis and U. expansa removed all measurable NO 3 - within 8 and 12 h, respectively, and in the medium and high treatments, removal was high and then decreased over time. Maximum mean uptake rates of nitrate were greater for U. expansa (∼300 μmol · g dwt -1  · h -1 ) than U. intestinalis (∼100 μmol · g dwt -1  · h -1 ); however, uptake rates were highly variable over time. Overall, U. expansa uptake rates were double those of U. intestinalis. Maximum tissue NO 3 - for U. expansa was >1,000 ppm, five times that of U. intestinalis, suggesting that U. expansa has a greater storage capacity in this cellular pool. These results showed that opportunistic green algae with differing tissue nutrient histories were able to efficiently remove nitrate from the water across a wide range of N pulses; thus, both are highly adapted to proliferate in estuarine environments with pulsed nutrient supplies. © 2011 Phycological Society of America.

Ouabain-binding and 86rubidium-uptake in lymphocytes of normal and borderline hypertensive subjects

DEFF Research Database (Denmark)

Nielsen, J R; Pedersen, K E; Johansen, Torben

1983-01-01

activity were studied in lymphocytes of nine borderline hypertensives (27 (20-36) years) and nine controls (28 (20-36) years). Maximum 3H-ouabain binding and 86Rb-uptake were taken as measures of the number of pump sites and cation pump activity, respectively. The median number of sodium/potassium pump...... to increased cation pump activity in lymphocytes of BH subjects in vitro may be interpreted as an adaptive change possibly induced by a circulating natriuretic substance....

Thyroid Scan and Uptake

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Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Thyroid Scan and Uptake Thyroid scan and uptake uses ...

Normal cerebral FDG uptake during childhood

International Nuclear Information System (INIS)

London, Kevin; Howman-Giles, Robert

2014-01-01

Current understanding of cerebral FDG uptake during childhood originates from a small number of studies in patients with neurological abnormalities. Our aim was to describe cerebral FDG uptake in a dataset of FDG PET scans in children more likely to represent a normal population. We reviewed cerebral FDG PET scans in children up to 16 years of age with suspected/proven extracranial malignancies and the following exclusions: central nervous system metastases, previous malignancies, previous chemotherapy or radiotherapy, development of cerebral metastases during therapy, neurological conditions, taking antiepileptic medication or medications likely to interfere with cerebral metabolism, and general anaesthesia within 24 h. White matter, basal ganglia, thalamus and the cerebellar cortex were analysed using regional SUV max , and the cerebral cortex, basal ganglia, thalamus and cerebellum were analysed using a regional relative uptake analysis in comparison to maximal cortical uptake. Scans from 30 patients (age range 11 months to 16 years, mean age 10 years 5 months) were included. All regions showed increasing SUV max with age. The parietal, occipital, lateral temporal and medial temporal lobes showed lower rates of increasing FDG uptake causing changing patterns of regional FDG uptake during childhood. The cortical regions showing the most intense uptake in early childhood were the parietal and occipital lobes. At approximately 7 years of age these regions had relatively less uptake than the frontal lobes and at approximately 10 years of age these regions had relatively less uptake than the thalamus. Relative FDG uptake in the brain has not reached an adult pattern by 1 year of age, but continues to change up to 16 years of age. The changing pattern is due to different regional rates of increasing cortical FDG uptake, which is less rapid in the parietal, occipital and temporal lobes than in the frontal lobes. (orig.)

Normal cerebral FDG uptake during childhood

Energy Technology Data Exchange (ETDEWEB)

London, Kevin [The Children' s Hospital at Westmead, Department of Nuclear Medicine, Sydney, NSW (Australia); University of Sydney, Discipline of Paediatrics and Child Health, Sydney Medical School, Sydney, NSW (Australia); Howman-Giles, Robert [The Children' s Hospital at Westmead, Department of Nuclear Medicine, Sydney, NSW (Australia); University of Sydney, Disciplines of Imaging and Paediatrics and Child Health, Sydney Medical School, Sydney, NSW (Australia)

2014-04-15

Current understanding of cerebral FDG uptake during childhood originates from a small number of studies in patients with neurological abnormalities. Our aim was to describe cerebral FDG uptake in a dataset of FDG PET scans in children more likely to represent a normal population. We reviewed cerebral FDG PET scans in children up to 16 years of age with suspected/proven extracranial malignancies and the following exclusions: central nervous system metastases, previous malignancies, previous chemotherapy or radiotherapy, development of cerebral metastases during therapy, neurological conditions, taking antiepileptic medication or medications likely to interfere with cerebral metabolism, and general anaesthesia within 24 h. White matter, basal ganglia, thalamus and the cerebellar cortex were analysed using regional SUV{sub max}, and the cerebral cortex, basal ganglia, thalamus and cerebellum were analysed using a regional relative uptake analysis in comparison to maximal cortical uptake. Scans from 30 patients (age range 11 months to 16 years, mean age 10 years 5 months) were included. All regions showed increasing SUV{sub max} with age. The parietal, occipital, lateral temporal and medial temporal lobes showed lower rates of increasing FDG uptake causing changing patterns of regional FDG uptake during childhood. The cortical regions showing the most intense uptake in early childhood were the parietal and occipital lobes. At approximately 7 years of age these regions had relatively less uptake than the frontal lobes and at approximately 10 years of age these regions had relatively less uptake than the thalamus. Relative FDG uptake in the brain has not reached an adult pattern by 1 year of age, but continues to change up to 16 years of age. The changing pattern is due to different regional rates of increasing cortical FDG uptake, which is less rapid in the parietal, occipital and temporal lobes than in the frontal lobes. (orig.)

Accelerated Carbonation of Steel Slags Using CO{sub 2} Diluted Sources: CO{sub 2} Uptakes and Energy Requirements

Energy Technology Data Exchange (ETDEWEB)

Baciocchi, Renato, E-mail: baciocchi@ing.uniroma2.it; Costa, Giulia [Department of Civil Engineering and Computer Science Engineering, University of Rome “Tor Vergata”, Rome (Italy); Polettini, Alessandra; Pomi, Raffaella; Stramazzo, Alessio [Department of Civil and Environmental Engineering, University of Rome “La Sapienza”, Rome (Italy); Zingaretti, Daniela [Department of Civil Engineering and Computer Science Engineering, University of Rome “Tor Vergata”, Rome (Italy)

2016-01-18

This work presents the results of carbonation experiments performed on Basic Oxygen Furnace (BOF) steel slag samples employing gas mixtures containing 40 and 10% CO{sub 2} vol. simulating the gaseous effluents of gasification and combustion processes respectively, as well as 100% CO{sub 2} for comparison purposes. Two routes were tested, the slurry-phase (L/S = 5 l/kg, T = 100°C and Ptot = 10 bar) and the thin-film (L/S = 0.3–0.4 l kg, T = 50°C and Ptot = 7–10 bar) routes. For each one, the CO{sub 2} uptake achieved as a function of the reaction time was analyzed and on this basis, the energy requirements associated with each carbonation route and gas mixture composition were estimated considering to store the CO{sub 2} emissions of a medium size natural gas fired power plant (20 MW). For the slurry-phase route, maximum CO{sub 2} uptakes ranged from around 8% at 10% CO{sub 2}, to 21.1% (BOF-a) and 29.2% (BOF-b) at 40% CO{sub 2} and 32.5% (BOF-a) and 40.3% (BOF-b) at 100% CO{sub 2}. For the thin-film route, maximum uptakes of 13% (BOF-c) and 19.5% (BOF-d) at 40% CO{sub 2}, and 17.8% (BOF-c) and 20.2% (BOF-d) at 100% were attained. The energy requirements of the two analyzed process routes appeared to depend chiefly on the CO{sub 2} uptake of the slag. For both process route, the minimum overall energy requirements were found for the tests with 40% CO{sub 2} flows (i.e., 1400−1600 MJ/t{sub CO{sub 2}} for the slurry-phase and 2220 – 2550 MJ/t{sub CO{sub 2}} for the thin-film route).

Mercury resistant bacteria from effluents of paint factory : characterisation and mercury uptake ability

International Nuclear Information System (INIS)

Yasmin, A.; Afrasayab, S.; Hasnain, S.

1998-01-01

Twelve Hg-resistant strains [SHg-13,SHg-14, SHg-15, SHg-16, SHg-17, SHg-18, SHg-19, SHg-20, SHg-21, SHg-22, SHg-23, SHg-24] were isolated from the polluted water sample taken from the outlets of ICI paint factory. They could tolerate 350-500 mu g ml/sup -1/ of HgCl/sub 2/ in the solid medium and 25-125 mu g mg/sup -1/ of HgCl/sub 2/ in the liquid medium. All strains had off-white, convex [except SHg-20 which had orange flat colonies] and circular colonies. SHg-13, SHg-15 and SHg-17 were Gram variable rods, while rest of strains had Gram -ve rods. They were strictly aerobic bacteria except SHg-16, SHg-18, SHg-22 and SHg-24 which were facilitative anaerobes. On the basis of morphological and biochemical characters strains SHg-13, Shg-14, SHg-15, SHg-17, SHg-19, SHg-20, SHg-21, SHg-23 were affiliated with family Pseudomonadaceae, whereas strains SHg-16, SHg-18, SHg-22 and SHg-24 could be grouped with family Vibranoaceae. All strains could grow in pH range from 6-9 with different optimum, SHg-14 and SHg-16 yielded maximum growth at 28 deg. C while SHg-17, SHg-18, SHg-20, SHg-22 and SHg-23 showed optimum growth at 32 deg. C, whereas rest of the strains yielded maximum growth at 37 deg. C. They conferred resistance to ampicillin and chloramphenicol, but were sensitive to streptomycin [except SHg-20, SHg-23], kanamycin [except SHg-24] and tetracycline [excluding SHg-13, SHg-18]. These isolates could tolerate a number of other metallic salts. Excluding Shg-19 all strains harbor single plasmid. These strains had the ability to uptake/transform mercury. Maximum mercury uptake was observed by SHg-14 and SHg-15. (author)

Increased muscle glucose uptake during contractions

DEFF Research Database (Denmark)

Ploug, Thorkil; Galbo, Henrik; Richter, Erik

1984-01-01

We reinvestigated the prevailing concept that muscle contractions only elicit increased muscle glucose uptake in the presence of a so-called "permissive" concentration of insulin (Berger et al., Biochem. J. 146: 231-238, 1975; Vranic and Berger, Diabetes 28: 147-163, 1979). Hindquarters from rats...... in severe ketoacidosis were perfused with a perfusate containing insulin antiserum. After 60 min perfusion, electrical stimulation increased glucose uptake of the contracting muscles fivefold. Also, subsequent contractions increased glucose uptake in hindquarters from nondiabetic rats perfused for 1.5 h......-methylglucose uptake increased during contractions and glucose uptake was negative at rest and zero during contractions. An increase in muscle transport and uptake of glucose during contractions does not require the presence of insulin. Furthermore, glucose transport in contracting muscle may only increase if glycogen...

Thyroid Scan and Uptake

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Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician ... of nuclear medicine imaging. The radioactive iodine uptake test (RAIU) is also known as a thyroid uptake. ...

FDG-PET/CT and diffusion-weighted imaging for resected lung cancer: correlation of maximum standardized uptake value and apparent diffusion coefficient value with prognostic factors.

Science.gov (United States)

Usuda, Katsuo; Funasaki, Aika; Sekimura, Atsushi; Motono, Nozomu; Matoba, Munetaka; Doai, Mariko; Yamada, Sohsuke; Ueda, Yoshimichi; Uramoto, Hidetaka

2018-04-09

Diffusion-weighted magnetic resonance imaging (DWI) is useful for detecting malignant tumors and the assessment of lymph nodes, as FDG-PET/CT is. But it is not clear how DWI influences the prognosis of lung cancer patients. The focus of this study is to evaluate the correlations between maximum standardized uptake value (SUVmax) of FDG-PET/CT and apparent diffusion coefficient (ADC) value of DWI with known prognostic factors in resected lung cancer. A total of 227 patients with resected lung cancers were enrolled in this study. FEG-PET/CT and DWI were performed in each patient before surgery. There were 168 patients with adenocarcinoma, 44 patients with squamous cell carcinoma, and 15 patients with other cell types. SUVmax was a factor that was correlated to T factor, N factor, or cell differentiation. ADC of lung cancer was a factor that was not correlated to T factor, or N factor. There was a significantly weak inverse relationship between SUVmax and ADC (Correlation coefficient r = - 0.227). In analysis of survival, there were significant differences between the categories of sex, age, pT factor, pN factor, cell differentiation, cell type, and SUVmax. Univariate analysis revealed that SUVmax, pN factor, age, cell differentiation, cell type, sex, and pT factor were significant factors. Multivariate analysis revealed that SUVmax and pN factor were independent significant prognostic factors. SUVmax was a significant prognostic factor that is correlated to T factor, N factor, or cell differentiation, but ADC was not. SUVmax may be more useful for predicting the prognosis of lung cancer than ADC values.

pH dependence of the isoproterenol-induced /sup 45/Ca net uptake into the ventricular myocardium of rats

Energy Technology Data Exchange (ETDEWEB)

Haag, R

1975-01-01

Infarction-like or disseminated myocardial necroses can be produced in rats by high doses of isoprotenerol which stimulates the decomposition of energy-rich phosphates to a maximum. The paper shows that acidoses of different genesis (peroral administration of NH/sub 4/Cl, artificial respiration with CO/sub 2/) induced experimentally can inhibit the isoproterenol-induced /sup 45/Ca net uptake and the production of necroses. The findings suggest that Ca/sup + +/ ions play a key role in the production of myocardial necroses which has not been recognized until now - that increased Ca/sup + +/ uptake into damaged myocardial fibres is a result or, at the most, an accompanying symptom of necrosis production - should therefore be discarded.

Relative Water Uptake as a Criterion for the Design of Trickle Irrigation Systems

Science.gov (United States)

Communar, G.; Friedman, S. P.

2008-12-01

Previously derived analytical solutions to the 2- and 3-dimensional water flow problems describing trickle irrigation are not being widely used in practice because those formulations either ignore root water uptake or refer to it as a known input. In this lecture we are going to describe a new modeling approach and demonstrate its applicability for designing the geometry of trickle irrigation systems, namely the spacing between the emitters and drip lines. The major difference between our and previous modeling approaches is that we refer to the root water uptake as to the unknown solution of the problem and not as to a known input. We postulate that the solution to the steady-state water flow problem with a root sink that is acting under constant, maximum suction defines un upper bound to the relative water uptake (water use efficiency) in actual transient situations and propose to use it as a design criterion. Following previous derivations of analytical solutions we assume that the soil hydraulic conductivity increases exponentially with its matric head, which allows the linearization of the Richards equation, formulated in terms of the Kirchhoff matric flux potential. Since the transformed problem is linear, the relative water uptake for any given configuration of point or line sources and sinks can be calculated by superposition of the Green's functions of all relevant water sources and sinks. In addition to evaluating the relative water uptake, we also derived analytical expressions for the steam functions. The stream lines separating the water uptake zone from the percolating water provide insight to the dependence of the shape and extent of the actual rooting zone on the source- sink geometry and soil properties. A minimal number of just 3 system parameters: Gardner's (1958) alfa as a soil type quantifier and the depth and diameter of the pre-assumed active root zone are sufficient to characterize the interplay between capillary and gravitational effects on

The influence of I-131 therapy on FDG uptake in differentiated thyroid cancer

International Nuclear Information System (INIS)

Hung Guanguei; Lee Kwowhei; Liao Peiyung; Yang Liheng; Yang Kwangtao

2008-01-01

18F-fluorodeoxyglucose positron emission tomography (FDG-PET) [or PET/computed tomography (CT)] is more likely to show false-negative results when it is performed shortly after chemotherapy and/or radiotherapy because of ''metabolic stunning''. The present study aimed to evaluate the influence of I-131 therapy on FDG uptake and the detection of recurrence or metastasis of differentiated thyroid cancer (DTC). We retrospectively enrolled 16 consecutive FDG-PET/CT studies which had been performed in patients with DTC with elevated thyroglobulin (TG) but negative I-131 whole-body scan. All studies were performed under L-thyroxine suppression. The patients were divided into groups A and B for PET/CT performed within 4 months of I-131 therapy or no such therapy, respectively. Each lesion identified on PET/CT was characterized using a 5-point scale by visual analysis: 0=definitely benign, 1=probably benign, 2=equivocal, 3=probably malignant, and 4=definitely malignant. The maximum standardized uptake value (SUV max ) in each lesion was also measured for semiquantitative analysis. We compared the visual grading and SUV max of the lesion of highest FDG uptake between groups A and B. For visual analysis, group B had significantly more patients with an uptake score of 3 or 4 than group A (80% vs. 17%, P=0.01). In addition, there were significantly more equivocal results from group A than from group B (67% vs. 10%, P=0.02). If the patients with the highest uptake scores of 2, 3, and 4 were considered to be positive for local recurrence or metastasis, there would be no significant difference between the positive rates of groups A and B (83% vs. 90%, P=0.7). However, the mean SUV max of positive results was significantly lower for group A than for group B (3.1±0.9 and 6.6±3.5 respectively, P=0.02). The preliminary results suggested that FDG uptake in DTC may be negatively influenced by I-131 therapy within 4 months, resulting in lower FDG uptake and more equivocal results

FDG uptake heterogeneity evaluated by fractal analysis improves the differential diagnosis of pulmonary nodules

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Miwa, Kenta, E-mail: kenta5710@gmail.com [Department of Nuclear Medicine, Cancer Institute Hospital of Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Division of Medical Quantum Science, Department of Health Sciences, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Inubushi, Masayuki, E-mail: inubushi@med.kawasaki-m.ac.jp [Department of Nuclear Medicine, Kawasaki Medical School, 577 Matsushima Kurashiki, Okayama 701-0192 (Japan); Wagatsuma, Kei, E-mail: kei1192@hotmail.co.jp [Department of Nuclear Medicine, Cancer Institute Hospital of Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Nagao, Michinobu, E-mail: minagao@radiol.med.kyushu-u.ac.jp [Department of Molecular Imaging and Diagnosis, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Murata, Taisuke, E-mail: taisuke113@gmail.com [Department of Nuclear Medicine, Cancer Institute Hospital of Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Koyama, Masamichi, E-mail: masamichi.koyama@jfcr.or.jp [Department of Nuclear Medicine, Cancer Institute Hospital of Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Koizumi, Mitsuru, E-mail: mitsuru@jfcr.or.jp [Department of Nuclear Medicine, Cancer Institute Hospital of Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Sasaki, Masayuki, E-mail: msasaki@hs.med.kyushu-u.ac.jp [Division of Medical Quantum Science, Department of Health Sciences, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan)

2014-04-15

Purpose: The present study aimed to determine whether fractal analysis of morphological complexity and intratumoral heterogeneity of FDG uptake can help to differentiate malignant from benign pulmonary nodules. Materials and methods: We retrospectively analyzed data from 54 patients with suspected non-small cell lung cancer (NSCLC) who were examined by FDG PET/CT. Pathological assessments of biopsy specimens confirmed 35 and 19 nodules as NSCLC and inflammatory lesions, respectively. The morphological fractal dimension (m-FD), maximum standardized uptake value (SUV{sub max}) and density fractal dimension (d-FD) of target nodules were calculated from CT and PET images. Fractal dimension is a quantitative index of morphological complexity and tracer uptake heterogeneity; higher values indicate increased complexity and heterogeneity. Results: The m-FD, SUV{sub max} and d-FD significantly differed between malignant and benign pulmonary nodules (p < 0.05). Although the diagnostic ability was better for d-FD than m-FD and SUV{sub max}, the difference did not reach statistical significance. Tumor size correlated significantly with SUV{sub max} (r = 0.51, p < 0.05), but not with either m-FD or d-FD. Furthermore, m-FD combined with either SUV{sub max} or d-FD improved diagnostic accuracy to 92.6% and 94.4%, respectively. Conclusion: The d-FD of intratumoral heterogeneity of FDG uptake can help to differentially diagnose malignant and benign pulmonary nodules. The SUV{sub max} and d-FD obtained from FDG-PET images provide different types of information that are equally useful for differential diagnoses. Furthermore, the morphological complexity determined by CT combined with heterogeneous FDG uptake determined by PET improved diagnostic accuracy.

Radioiodine uptake in inactive pulmonary tuberculosis

International Nuclear Information System (INIS)

Bakheet, S.M.; Powe, J.; Al Suhaibani, H.; Hammami, M.M.; Bazarbashi, M.

1999-01-01

Radioiodine may accumulate at sites of inflammation or infection. We have seen such accumulation in six thyroid cancer patients with a history of previously treated pulmonary tuberculosis. We also review the causes of false-positive radioiodine uptake in lung infection/inflammation. Eight foci of radioiodine uptake were seen on six iodine-123 diagnostic scans. In three foci, the uptake was focal and indistinguishable from thyroid cancer pulmonary metastases from thyroid cancer. In the remaining foci, the uptake appeared nonsegmental, linear or lobar, suggesting a false-positive finding. The uptake was unchanged, variable in appearance or non-persistent on follow-up scans and less extensive than the fibrocystic changes seen on chest radiographs. In the two patients studied, thyroid hormone level did not affect the radioiodine lung uptake and there was congruent gallium-67 uptake. None of the patients had any evidence of thyroid cancer recurrence or of reactivation of tuberculosis and only two patients had chronic intermittent chest symptoms. Severe bronchiectasis, active tuberculosis, acute bronchitis, respiratory bronchiolitis, rheumatoid arthritis-associated lung disease and fungal infection such as Allescheria boydii and aspergillosis can lead to different patterns of radioiodine chest uptake mimicking pulmonary metastases. Pulmonary scarring secondary to tuberculosis may predispose to localized radioiodine accumulation even in the absence of clinically evident active infection. False-positive radioiodine uptake due to pulmonary infection/inflammation should be considered in thyroid cancer patients prior to the diagnosis of pulmonary metastases. (orig.)

Association of primary tumour FDG uptake with clinical, histopathological and molecular characteristics in breast cancer patients scheduled for neoadjuvant chemotherapy

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Koolen, B.B.; Aukema, T.S. [Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Department of Nuclear Medicine, Amsterdam (Netherlands); Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Department of Surgical Oncology, Amsterdam (Netherlands); Vrancken Peeters, M.J.T.F.D.; Rutgers, E.J.T. [Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Department of Surgical Oncology, Amsterdam (Netherlands); Wesseling, J.; Lips, E.H. [Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Department of Pathology and Experimental Therapy, Amsterdam (Netherlands); Vogel, W.V.; Valdes Olmos, R.A. [Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Department of Nuclear Medicine, Amsterdam (Netherlands); Werkhoven, E. van [Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Department of Biometrics, Amsterdam (Netherlands); Gilhuijs, K.G.A. [Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Department of Radiology, Amsterdam (Netherlands); University Medical Centre Utrecht, Department of Radiology, Utrecht (Netherlands); Rodenhuis, S. [Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Department of Medical Oncology, Amsterdam (Netherlands)

2012-12-15

The aim of this study was to evaluate the association of primary tumour {sup 18}F-fluorodeoxyglucose (FDG) uptake with clinical, histopathological and molecular characteristics of breast cancer patients scheduled for neoadjuvant chemotherapy. Second, we wished to establish for which patients pretreatment positron emission tomography (PET)/CT could safely be omitted because of low FDG uptake. PET/CT was performed in 214 primary stage II or III breast cancer patients in the prone position with hanging breasts. Tumour FDG uptake was qualitatively evaluated to determine the possibility of response monitoring with PET/CT and was quantitatively assessed using maximum standardized uptake values (SUV{sub max}). FDG uptake was compared with age, TNM stage, histology, hormone and human epidermal growth factor receptor 2 status, grade, Ki-67 and molecular subtype in univariable and multivariable analyses. In 203 tumours (95 %) FDG uptake was considered sufficient for response monitoring. No subgroup of patients with consistently low tumour FDG uptake could be identified. In a univariable analysis, SUV{sub max} was significantly higher in patients with distant metastases at staging examination, non-lobular carcinomas, tumours with negative hormone receptors, triple negative tumours, grade 3 tumours, and in tumours with a high proliferation index (Ki-67 expression). After multiple linear regression analysis, triple negative and grade 3 tumours were significantly associated with a higher SUV{sub max}. Primary tumour FDG uptake in breast cancer patients scheduled for neoadjuvant chemotherapy is significantly higher in tumours with prognostically unfavourable characteristics. Based on tumour characteristics associated with low tumour FDG uptake, this study was unable to identify a subgroup of patients unlikely to benefit from pretreatment PET/CT. (orig.)

Approximate maximum parsimony and ancestral maximum likelihood.

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Alon, Noga; Chor, Benny; Pardi, Fabio; Rapoport, Anat

2010-01-01

We explore the maximum parsimony (MP) and ancestral maximum likelihood (AML) criteria in phylogenetic tree reconstruction. Both problems are NP-hard, so we seek approximate solutions. We formulate the two problems as Steiner tree problems under appropriate distances. The gist of our approach is the succinct characterization of Steiner trees for a small number of leaves for the two distances. This enables the use of known Steiner tree approximation algorithms. The approach leads to a 16/9 approximation ratio for AML and asymptotically to a 1.55 approximation ratio for MP.

Clearance of the high intestinal 18F-FDG uptake associated with metformin after stopping the drug

International Nuclear Information System (INIS)

Oezuelker, Tamer; Oezuelker, Filiz; Oezpacaci, Tevfik; Mert, Meral

2010-01-01

This study was done to determine whether interruption of metformin before 18 F-FDG PET/CT imaging could prevent the increased 18 F-FDG uptake in the intestine caused by this drug. Included in the study were 41 patients with known type 2 diabetes mellitus who were referred to our department for evaluation of various neoplastic diseases. Patients underwent two 18 F-FDG PET/CT scans, the first while they were on metformin and the second after they had stopped metformin. They stopped metformin and did not take any other oral antidiabetic medication starting 3 days before the second study and their blood glucose level was regulated with insulin when necessary to keep it within the range 5.55-8.33 mmol/l. FDG uptake was graded visually according to a four-point scale and semiquantitatively by recording the maximum standardized uptake value (SUVmax) in different bowel segments. A paired-samples t-test method was used to determine whether there was a significant difference between SUVmax measurements and visual analysis scores of the metabolic activity of the bowel in the PET/CT scans before and after stopping metformin. Diffuse and intense 18 F-FDG uptake was observed in bowel segments of patients, and the activity in the colon was significantly decreased both visually and semiquantitatively in PET/CT scans performed after patients stopped metformin (p 0.05). Metformin causes an increase in 18 F-FDG uptake in the bowel and stopping metformin before PET/CT study significantly decreased this unwanted uptake, especially in the colon, facilitating the interpretation of images obtained from the abdomen and preventing the obliteration of lesions. (orig.)

Augmented internalisation of ferroportin to late endosomes impairs iron uptake by enterocyte-like IEC-6 cells.

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Oates, Phillip S; Thomas, Carla

2005-08-01

Absorption of iron occurs by duodenal enterocytes, involving uptake by the divalent metal transporter-1 (DMT1) and release by ferroportin. Ferroportin responds to the hepatocyte-produced 25-amino-acid-peptide hepcidin-25 by undergoing internalisation to late endosomes that impair iron release. Ferroportin is also expressed on the apical membrane of polarised Caco-2 cells, rat intestinal cells and in IEC-6 cells (an intestinal epithelial cell line). A blocking antibody to ferroportin also impairs the uptake, but not the release, of iron. In this study IEC-6 cells were used to study the mechanism of impairment or recovery from impairment produced by the blocking antibody and the fate of DMT1 and ferroportin. Uptake of 1 muM Fe(II) was studied by adding the antibody from time 0 and after adding or removing the antibody once a steady state had been reached. Surface binding, maximum iron transport rate V(max) and transporter affinity (K(m)) were measured after impairment of iron uptake. Ferroportin and DMT1 distribution were assessed by immunofluorescence microscopy. Antibody-mediated impairment, or recovery from impairment, of Fe(II) uptake occurred within minutes. Impairment was lost when the antibody was combined with the immunizing peptide. DMT1 and ferroportin undergo internalisation to late endosomes and, in the presence of the antibody, augmented internalisation of DMT1 and ferroportin caused swelling of late endosomes. Surface binding of Fe(II) and iron transport V(max) were reduced by 50%, indicating that the antibody removed membrane-bound DMT1. The ferroportin antibody induced rapid turnover of membrane ferroportin and DMT1 and its internalisation to late endosomes, resulting in impaired Fe(II) uptake.

Scoparia dulcis (SDF7) endowed with glucose uptake properties on L6 myotubes compared insulin.

Science.gov (United States)

Beh, Joo Ee; Latip, Jalifah; Abdullah, Mohd Puad; Ismail, Amin; Hamid, Muhajir

2010-05-04

Insulin stimulates glucose uptake and promotes the translocation of glucose transporter 4 (Glut 4) to the plasma membrane on L6 myotubes. The aim of this study is to investigate affect of Scoparia dulcis Linn water extracts on glucose uptake activity and the Glut 4 translocation components (i.e., IRS-1, PI 3-kinase, PKB/Akt2, PKC and TC 10) in L6 myotubes compared to insulin. Extract from TLC fraction-7 (SDF7) was used in this study. The L6 myotubes were treated by various concentrations of SDF7 (1 to 50 microg/ml) and insulin (1 to 100 nM). The glucose uptake activities of L6 myotubes were evaluated using 2-Deoxy-D-glucose uptake assay in with or without fatty acid-induced medium. The Glut 4 translocation components in SDF7-treated L6 myotubes were detected using immunoblotting and quantified by densitometry compared to insulin. Plasma membrane lawn assay and glycogen colorimetry assay were carried out in SDF7- and insulin-treated L6 myotubes in this study. Here, our data clearly shows that SDF7 possesses glucose uptake properties on L6 myotubes that are dose-dependent, time-dependent and plasma membrane Glut 4 expression-dependent. SDF7 successfully stimulates glucose uptake activity as potent as insulin at a maximum concentration of 50 microg/ml at 480 min on L6 myotubes. Furthermore, SDF7 stimulates increased Glut 4 expression and translocation to plasma membranes at equivalent times. Even in the insulin resistance stage (free fatty acids-induced), SDF7-treated L6 myotubes were found to be more capable at glucose transport than insulin treatment. Thus, we suggested that Scoparia dulcis has the potential to be categorized as a hypoglycemic medicinal plant based on its good glucose transport properties. (c) 2010 Elsevier Ireland Ltd. All rights reserved.

(18)F-FDG uptake predicts diagnostic yield of transbronchial biopsy in peripheral lung cancer.

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Umeda, Yukihiro; Demura, Yoshiki; Anzai, Masaki; Matsuoka, Hiroki; Araya, Tomoyuki; Nishitsuji, Masaru; Nishi, Koichi; Tsuchida, Tatsuro; Sumida, Yasuyuki; Morikawa, Miwa; Ameshima, Shingo; Ishizaki, Takeshi; Kasahara, Kazuo; Ishizuka, Tamotsu

2014-07-01

Recent advances in endobronchial ultrasonography with a guide sheath (EBUS-GS) have enabled better visualization of distal airways, while virtual bronchoscopic navigation (VBN) has been shown useful as a guide to navigate the bronchoscope. However, indications for utilizing VBN and EBUS-GS are not always clear. To clarify indications for a bronchoscopic examination using VBN and EBUS-GS, we evaluated factors that predict the diagnostic yield of a transbronchial biopsy (TBB) procedure for peripheral lung cancer (PLC) lesions. We retrospectively reviewed the charts of 194 patients with 201 PLC lesions (≤3cm mean diameter), and analyzed the association of diagnostic yield of TBB with [(18)F]-fluoro-2-deoxy-d-glucose ((18)F-FDG) positron emission tomography and chest computed tomography (CT) findings. The diagnostic yield of TBB using VBN and EBUS-GS was 66.7%. High maximum standardized uptake value (SUVmax), positive bronchus sign, and ground-glass opacity component shown on CT were all significant predictors of diagnostic yield, while multivariate analysis showed only high (18)F-FDG uptake (SUVmax ≥2.8) and positive bronchus sign as significant predictors. Diagnostic yield was higher for PLC lesions with high (18)F-FDG uptake (SUVmax ≥2.8) and positive bronchus sign (84.6%) than for those with SUVmax PLC lesions. (18)F-FDG uptake and bronchus sign may indicate for the accurate application of bronchoscopy with those modalities for diagnosing PLC. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Root uptake of transuranic elements

International Nuclear Information System (INIS)

Schulz, R.K.

1977-01-01

The uptake of elements by plant roots is one of the important pathways of entry of many elements into the food chain of man. Data are cited showing plutonium concentration ratios, plant/soil, ranging from 10 -10 to 10 -3 . Concentration ratios for americium range from 10 -7 to 10 +1 . Limited experiments with curium and neptunium indicate that root uptake of curium is similar to that of americium and that plant uptake of neptunium is substantially larger than that of curium and americium. The extreme ranges of concentration ratios cited for plutonium and americium are due to a number of causes. Experimental conditions such as very intensive cropping will lead to abnormally high concentration ratios. In some experiments, addition of chelating agents markedly increased plant root uptake of transuranic elements. Particle size and composition of the source material influenced uptake of the transuranics by plants. Translocation within the plant, and soil factors such as pH and organic matter content, all affect concentration ratios

Effect of partially purified components of zoospores and mycelia of phytophthora infestans on uptake of 3H-leucine by potato tuber disks

International Nuclear Information System (INIS)

Nishimura, Norio; Tomiyama, Kohei; Doke, Noriyuki

1980-01-01

The zoosporial component of Phytophthora infestans, which was previously reported to cause reduction of 3 H-leucine uptake by potato tuber disks, was partially purified. Precipitate (A-fraction) was obtained by homogenizing zoospores with acetate buffer at pH 4.5 and centrifuging at 20,000 x g, and the A-fraction was suspended in borate buffer at pH 8.8, boiled for 1 hr and then centrifuged at 20,000 x g, giving the precipitate (B-fraction) and supernatant (C-fraction). Ten ml of 10 mM tris-HCl buffer containing 1 mM CaCl 2 at pH 7.4 was used to suspend A and B-fraction. The buffer was used as a control. A, B and C fractions obtained from 5 - 6 x 10 6 zoosprores reducted uptake of 3 H-leucine by the tuber disks of potato cv. Rishiri, but the inhibition rates caused by these fractions differed markedly. However, very high correlation was found between inhibition rates of 3 H-leucine uptake and sugar contents of these fractions. There was no difference in the inhibition rates between the zoosporial components of incompatible and compatible races, when the activities were expressed in terms of the sugar contents. The mycelial components of P. infestans extracted by the modified method of Lisker and Kuc which was used to extract phytoalexin elicitor from that of P. infestans, also had the same effect as the zoosporial components (A, B, and C-fraction) on 3 H-leucine uptake by the disks. C-fraction containing 15 μg of sugar per ml sufficed to inhibit 3 H-leucine uptake at the maximum rate, and the maximum rate of inhibition was attained within 2 hr after the zoosporial component (C-fraction containing 30 μg sugar/ml) was administered to the disks. (author)

Does the intensity of diffuse thyroid gland uptake on F-18 fluorodeoxyglucose positron emission tomography/computed tomography scan predict the severity of hypothyroidism? Correlation between maximal standardized uptake value and serum thyroid stimulating hormone levels

International Nuclear Information System (INIS)

Pruthi, Ankur; Choudhury, Partha Sarathi; Gupta, Manoj; Taywade, Sameer

2015-01-01

F-18 fluorodeoxyglucose (F-18 FDG) positron emission tomography/computed tomography (PET/CT) scan and hypothyroidism. The aim was to determine whether the intensity of diffuse thyroid gland uptake on F-18 FDG PET/CT scans predicts the severity of hypothyroidism. A retrospective analysis of 3868 patients who underwent F-18 FDG PET/CT scans, between October 2012 and June 2013 in our institution for various oncological indications was done. Out of them, 106 (2.7%) patients (79 females, 27 males) presented with bilateral diffuse thyroid gland uptake as an incidental finding. These patients were investigated retrospectively and various parameters such as age, sex, primary cancer site, maximal standardized uptake value (SUVmax), results of thyroid function tests (TFTs) and fine-needle aspiration cytology results were noted. The SUVmax values were correlated with serum thyroid stimulating hormone (S. TSH) levels using Pearson's correlation analysis. Pearson's correlation analysis. Clinical information and TFT (serum FT3, FT4 and TSH levels) results were available for 31 of the 106 patients (27 females, 4 males; mean age 51.5 years). Twenty-six out of 31 patients (84%) were having abnormal TFTs with abnormal TSH levels in 24/31 patients (mean S. TSH: 22.35 μIU/ml, median: 7.37 μIU/ml, range: 0.074-211 μIU/ml). Among 7 patients with normal TSH levels, 2 patients demonstrated low FT3 and FT4 levels. No significant correlation was found between maximum standardized uptake value and TSH levels (r = 0.115, P > 0.05). Incidentally detected diffuse thyroid gland uptake on F-18 FDG PET/CT scan was usually associated with hypothyroidism probably caused by autoimmune thyroiditis. Patients should be investigated promptly irrespective of the intensity of FDG uptake with TFTs to initiate replacement therapy and a USG examination to look for any suspicious nodules

Colonic uptake patterns of F-18-FDG PET in asymptomatic adults: correlation with colonoscopic findings

International Nuclear Information System (INIS)

Pai, M.; Cho, Y.; Shim, K

2004-01-01

Physiologic intestinal FDG uptake is frequently observed in asymptomatic individuals for cancer screening FDG PET. Colonic FDG accumulation is a well-known confusing findings that interfere true cancer detection or cause false positive. The aim of this study was to evaluate the pattern and intensity of colonic uptake in whole body FDG PET in asymptomatic healthy adults and to correlate those with colonoscopic findings. We reviewed retrospectively 64 subjects (age: 27-87, M:F = 31:33) who underwent both FDG PET and colonoscopy for cancer screening. FDG uptake pattern was classified as focal, segmental and diffuse. Maximum SUV were measured. The PET results were compared with colonoscopic and histologic findings. In 34 patients FDG bowel uptake was interpreted as diffuse(group I), in 17 patients as segmental(group II) and in 13 patients as focal uptake(group III). Six adenomas(17.6%, average diameter = 5 mm) were found in group I, 7 adenomas (41.1%, 5.57 mm) in group II and 4 adenomas and 1 adenocarcinoma (30.7%, 16.4 mm) in group III. There was no difference in averages of SUV between patients with adenoma and with negative colonoscopic results in each group of intestinal FDG pattern (group I: 1.675±1.15 vs 1.94±0.62, group II: 4.78±3.66 vs 4.23±1.13, group III: 6.50±4.68 vs 4.1±1.01). Large adenomas( >1 cm) were detected more frequently in group III (4 out of 5) rather than in group II (1 out of 7) or group I (none) and had higher SUV (6.30±4.84) than small adenomas (3.74±3.23). In group III, 4 patients without adenomas were non-physiologic(30.7%, 2 intestinal tuberculosis, 2 mucosal ulcer). Focal FDG uptake is associated more often with large adenoma and other pathologic findings in colonoscopy. Segmental uptake cannot discriminate presence of adenoma from negative results, while diffuse pattern may imply normal or having small adenomas

Characterization of cadmium uptake in Lactobacillus plantarum and isolation of cadmium and manganese uptake mutants

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Hao, Z.; Reiske, H.R.; Wilson, D.B.

1999-11-01

Two different Cd{sup 2+} uptake systems were identified in Lactobacillus plantarum. One is a high-affinity, high-velocity Mn{sup 2+} uptake system which also takes up Cd{sup 2+} and is induced by Mn{sup 2+} starvation. The calculated K{sub m} and V{sub max} are 0.26 {mu}M and 3.6 {mu}mol g of dry cell{sup {minus}1} min{sup {minus}1}, respectively. Unlike Mn{sup 2+} uptake, which is facilitated by citrate and related tricarboxylic acids, Cd{sup 2+} uptake is weakly inhibited by citrate. Cd{sup 2+} and Mn{sup 2+} are competitive inhibitors of each other, and the affinity of the system for Cd{sup 2+} is higher than that for Mn{sup 2+}. The other Cd{sup 2+} uptake system is expressed in Mn{sup 2+}-sufficient cells, and no K{sub m} can be calculated for it because uptake is nonsaturable. Mn{sup 2+} does not compete for transport through this system, nor does any other tested cation, i.e., Zn{sup 2+}, Cu{sup 2+}, Co{sup 2+}, Mg{sup 2+}, Ca{sup 2+}, Fe{sup 2+}, or Ni{sup 2+}. Both systems require energy, since uncouplers completely inhibit their activities. Two Mn{sup 2+}-dependent L. plantarum mutants were isolated by chemical mutagenesis and ampicillin enrichment. They required more than 5,000 times as much Mn{sup 2+} for growth as the parental strain. Mn{sup 2+} starvation-induced Cd{sup 2+} uptake in both mutants was less than 5% the wild-type rate. The low level of long-term Mn{sup 2+} or Cd{sup 2+} accumulation by the mutant strains also shows that the mutations eliminate the high-affinity Mn{sup 2+} and Cd{sup 2+} uptake system.

Rac1 governs exercise‐stimulated glucose uptake in skeletal muscle through regulation of GLUT4 translocation in mice

Science.gov (United States)

Nielsen, Ida L.; Kleinert, Maximilian; Møller, Lisbeth L. V.; Ploug, Thorkil; Schjerling, Peter; Bilan, Philip J.; Klip, Amira; Jensen, Thomas E.; Richter, Erik A.

2016-01-01

Key point Exercise increases skeletal muscle energy turnover and one of the important substrates for the working muscle is glucose taken up from the blood.The GTPase Rac1 can be activated by muscle contraction and has been found to be necessary for insulin‐stimulated glucose uptake, although its role in exercise‐stimulated glucose uptake is unknown.We show that Rac1 regulates the translocation of the glucose transporter GLUT4 to the plasma membrane in skeletal muscle during exercise.We find that Rac1 knockout mice display significantly reduced glucose uptake in skeletal muscle during exercise. Abstract Exercise increases skeletal muscle energy turnover and one of the important substrates for the working muscle is glucose taken up from the blood. Despite extensive efforts, the signalling mechanisms vital for glucose uptake during exercise are not yet fully understood, although the GTPase Rac1 is a candidate molecule. The present study investigated the role of Rac1 in muscle glucose uptake and substrate utilization during treadmill exercise in mice in vivo. Exercise‐induced uptake of radiolabelled 2‐deoxyglucose at 65% of maximum running capacity was blocked in soleus muscle and decreased by 80% and 60% in gastrocnemius and tibialis anterior muscles, respectively, in muscle‐specific inducible Rac1 knockout (mKO) mice compared to wild‐type littermates. By developing an assay to quantify endogenous GLUT4 translocation, we observed that GLUT4 content at the sarcolemma in response to exercise was reduced in Rac1 mKO muscle. Our findings implicate Rac1 as a regulatory element critical for controlling glucose uptake during exercise via regulation of GLUT4 translocation. PMID:27061726

Stone-ground wood pulp-reinforced polypropylene composites: Water uptake and thermal properties

Directory of Open Access Journals (Sweden)

Joan Pere López

2012-11-01

Full Text Available Two of the drawbacks of using natural-based composites in industrial applications are thermal instability and water uptake capacity. In this work, mechanical wood pulp was used to reinforce polypropylene at a level of 20 to 50 wt. %. Composites were mixed by means of a Brabender internal mixer for both non-coupled and coupled formulations. Differential scanning calorimetry (DSC and thermogravimetric analysis (TGA were used to determine the thermal properties of the composites. The water uptake behavior was evaluated by immersion of the composites in water until an equilibrium state was reached. Results of water absorption tests revealed that the amount of water absorption was clearly dependent upon the fiber content. The coupled composites showed lower water absorption compared to the uncoupled composites. The incorporation of mechanical wood pulp into the polypropylene matrix produced a clear nucleating effect by increasing the crystallinity degree of the polymer and also increasing the temperature of polymer degradation. The maximum degradation temperature for stone ground wood pulp–reinforced composites was in the range of 330 to 345 ºC.

Uptake of indium-111 labelled platelets by normal, nephrotic and transplanted kidneys

International Nuclear Information System (INIS)

Desir, G.; Lange, R.; Smith, E.; Bia, M.; Flye, M.; Kashgarian, M.; Canganelli, A.; Ezekowitz

1984-01-01

To determine the role of platelets in the genesis of renal transplant (T) rejection, the authors studied 3 groups of adult patients. Group I, n=8, had normal renal function (Cr=1 +- 0.1 mg%, Mean +- SD). Group II, n=9, had nephrotic syndrome (Cr=2.4 +- 1). Group III, n=7, consisted of 5 cadaveric (C) and 2 living related donor (LRD) T. In Group II, 1 patient had received a T 4 years prior to study. Group I and II received 448 +- 101 μCi and Group III 236 +- 51 μCi of Indium-111. In Groups I and II the first image was obtained 18 +- 6 hrs after injection. In Group II the first was obtained 6 +- 2 hr after injection and 1-3 times/day thereafter for a maximum of 7 days. Renal biopsies were obtained in all patients in Group III during imaging (n=5) or within 2 - 5 days of the last image. One patient was studied twice. In Group III, 5 patients received prednisone and azothiaprine and 2 prednisone and cyclosporine. Platelet uptake index (PUI) was calculated as the ratio of uptake over the T against a reference area. Rejection was diagnosed by biopsy. In groups I and II platelet uptake was seen only in the T patient. In Group III the PUI was 1.54 +- .13 in the rejecting T (n=5), 1.42 +- .2 in the non-rejecting T (n=3), 1.62 in a LRD non-rejecting T and 1.31 (n=2) in C non-rejecting T. In the four patients studied within 5 days of T the PUI was elevated at 1.47 +- .1. The authors conclude that: 1) platelets do not accumulate in normal or nephrotic native kidneys, 2) significant uptake occurs in the first week after C and LRD whether or not rejection is present, and 3) uptake in non-rejecting kidneys cannot be ascribed to perfusion induced endothelial injury since it was present in LRD transplants

Multi-Model Assessment of Trends and Variability in Terrestrial Carbon Uptake in India

Science.gov (United States)

Rao, A. S.; Bala, G.; Ravindranath, N. H.

2015-12-01

Indian terrestrial ecosystem exhibits large temporal and spatial variability in carbon sources and sinks due to its monsoon based climate system, diverse land use and land cover distribution and cultural practices. In this study, a multi-model based assessment is made to study the trends and variability in the land carbon uptake for India over the 20th century. Data from nine models which are a part of a recent land surface model intercomparison project called TRENDY is used for the study. These models are driven with common forcing data over the period of 1901-2010. Model output variables assessed include: gross primary production (GPP), heterotrophic respiration (Rh), autotrophic respiration (Ra) and net primary production (NPP). The net ecosystem productivity (NEP) for the Indian region was calculated as a difference of NPP and Rh and it was found that NEP for the region indicates an estimated increase in uptake over the century by -0.6 TgC/year per year. NPP for India also shows an increasing trend of 2.03% per decade from 1901-2010. Seasonal variation in the multimodel mean NPP is maximum during the southwest monsoon period (JJA) followed by the post monsoon period (SON) and is attributed to the maximum in rainfall for the region during the months of JJA. To attribute the changes seen in the land carbon variables, influence of climatic drivers such as precipitation, temperature and remote influences of large scale phenomenon such as ENSO on the land carbon of the region are also estimated in the study. It is found that although changes in precipitation shows a good correlation to the changes seen in NEP, remote drivers like ENSO do not have much effect on them. The Net Ecosystem Exchange is calculated with the inclusion of the land use change flux and fire flux from the models. NEE suggests that the region behaves as a small sink for carbon with an net uptake of 5 GtC over the past hundred years.

The role of seed coat phenolics on water uptake and early protein synthesis during germination of dimorphic seeds of halopyrum mucronatum (L.) staph

International Nuclear Information System (INIS)

Siddiqui, Z. S.; Khan, M.A.

2010-01-01

Role of seed coat phenolics on water uptake and early protein synthesis of Halopyrum mucronatum dimorphic seeds during germination were tested. Scanning electron micrographs (SEM) showed seed texture with differential deposition of secondary metabolites in both morphs. Ability of both seed morphs to retain secondary deposition was dependent on exposure to either saline or non-saline conditions. More phenols leached from the brown seed during the initial hours of soaking when compared to black seeds. Water uptake pattern was slightly different in both seed type particularly during initial hours when imbibition in black seeds showed little water uptake while in brown seeds absorption was quick in the first hour under both saline and non saline condition. Change in total protein was somewhat similar in both seeds morphs showing early increase (4 and 8 h), reaching to the maximum (12 h) and decreasing (24 and 48 h) afterward. The results are discussed in relation to seed coat phenolics, water uptake and early protein synthesis during germination. (author)

Effect of zinc and phosphorus on dry matter yield, uptake and utilization of 65Zn on Maize (Zea Mays L.) grown in a molli-soil

International Nuclear Information System (INIS)

Joshi, Megha; Shri Ram; Joshi, G.C.

2013-01-01

Zinc uptake and its utilization by Maize (Zea mays L.) variety Pragati using radiotracer 65 Zn technique along with varying levels of phosphorus treatments on dry matter yield was studied. The gamma activity was measured by calibrated NaI(Tl) gamma ray spectrometer. It was observed that zinc uptake in treatment T 2 found to be higher. However, treatment T 6 showed good growth parameters and dry matter yield. The 65 Zn activity was found maximum in roots and minimum in the leaves of maize plant. (author)

Radioiodine uptake by plants from soils

International Nuclear Information System (INIS)

Sabova, T.

1976-01-01

The uptake and accumulation of radioiodine by wheat, maize and peas from various types of soil have been studied. The uptake depends on the type of soil, on its content of organic matter and on the amount of fertilizer. Radioiodine is mainly accumulated in the roots. Accumulation in above-ground plant parts decreases in the following order: wheat, maize, peas. Uptake was highest from humus and clay soils and lowest from black and meadow soils. Application of chloride fertilizer or carrier iodine lead to an increase of radioiodine uptake in the whole plant. (author)

Effect of water management and silicon on germination, growth, phosphorus and arsenic uptake in rice.

Science.gov (United States)

Zia, Zahida; Bakhat, Hafiz Faiq; Saqib, Zulfiqar Ahmad; Shah, Ghulam Mustafa; Fahad, Shah; Ashraf, Muhammad Rizwan; Hammad, Hafiz Mohkum; Naseem, Wajid; Shahid, Muhammad

2017-10-01

Silicon (Si) is the 2nd most abundant element in soil which is known to enhance stress tolerance in wide variety of crops. Arsenic (As), a toxic metalloid enters into the human food chain through contaminated water and food or feed. To alleviate the deleterious effect of As on human health, it is a need of time to find out an effective strategy to reduce the As accumulation in the food chain. The experiments were conducted during September-December 2014, and 2016 to optimize Si concentration for rice (Oryza sativa L.) exposed to As stress. Further experiment were carried out to evaluate the effect of optimum Si on rice seed germination, seedling growth, phosphorus and As uptake in rice plant. During laboratory experiment, rice seeds were exposed to 150 and 300µM As with and without 3mM Si supplementation. Results revealed that As application, decreased the germination up to 40-50% as compared to control treatment. Arsenic stress also significantly (P management, significantly (P˂0.05) affected the plant growth, Si and As concentrations in the plant. Arsenic uptake was relatively less under aerobic conditions. The maximum As concentration (9.34 and 27.70mgkg DW -1 in shoot and root, respectively) was found in plant treated with 300µM As in absence of Si under anaerobic condition. Similarly, anaerobic condition resulted in higher As uptake in the plants. The study demonstrated that aerobic cultivation is suitable to decrease the As uptake and in rice exogenous Si supply is beneficial to decrease As uptake under both anaerobic and aerobic conditions. Copyright © 2017 Elsevier Inc. All rights reserved.

Nitrogen uptake and regeneration pathways in the equatorial Pacific: a basin scale modeling study

Directory of Open Access Journals (Sweden)

R. Le Borgne

2009-11-01

Full Text Available It is well known that most primary production is fueled by regenerated nitrogen in the open ocean. Therefore, studying the nitrogen cycle by focusing on uptake and regeneration pathways would advance our understanding of nitrogen dynamics in the marine ecosystem. Here, we carry out a basin-scale modeling study, by assessing model simulations of nitrate and ammonium, and rates of nitrate uptake, ammonium uptake and regeneration in the equatorial Pacific. Model-data comparisons show that the model is able to reproduce many observed features of nitrate, ammonium, such as the deep ammonium maximum (DAM. The model also reproduces the observed de-coupling of ammonium uptake and regeneration, i.e., regeneration rate greater than uptake rate in the lower euphotic zone. The de-coupling largely explains the observed DAM in the equatorial Pacific Ocean. Our study indicates that zooplankton excretion and remineralization of organic nitrogen play a different role in nitrogen regeneration. Rates of zooplankton excretion vary from <0.01 mmol m⁻³ d⁻¹ to 0.1 mmol m⁻³ d⁻¹ in the upper euphotic zone while rates of remineralization fall within a narrow range (0.015–0.025 mmol m⁻³ d⁻¹ . Zooplankton excretion contributes up to 70% of total ammonium regeneration in the euphotic zone, and is largely responsible for the spatial variability of nitrogen regeneration. However, remineralization provides a steady supply of ammonium in the upper ocean, and is a major source of inorganic nitrogen for the oligotrophic regions. Overall, ammonium generation and removal are approximately balanced over the top 150 m in the equatorial Pacific.

Insulin resistance and maximal oxygen uptake

DEFF Research Database (Denmark)

Seibaek, Marie; Vestergaard, Henrik; Burchardt, Hans

2003-01-01

BACKGROUND: Type 2 diabetes, coronary atherosclerosis, and physical fitness all correlate with insulin resistance, but the relative importance of each component is unknown. HYPOTHESIS: This study was undertaken to determine the relationship between insulin resistance, maximal oxygen uptake......, and the presence of either diabetes or ischemic heart disease. METHODS: The study population comprised 33 patients with and without diabetes and ischemic heart disease. Insulin resistance was measured by a hyperinsulinemic euglycemic clamp; maximal oxygen uptake was measured during a bicycle exercise test. RESULTS......: There was a strong correlation between maximal oxygen uptake and insulin-stimulated glucose uptake (r = 0.7, p = 0.001), and maximal oxygen uptake was the only factor of importance for determining insulin sensitivity in a model, which also included the presence of diabetes and ischemic heart disease. CONCLUSION...

Influence of tragacanth gum in egg white based bioplastics: Thermomechanical and water uptake properties.

Science.gov (United States)

López-Castejón, María Luisa; Bengoechea, Carlos; García-Morales, Moisés; Martínez, Inmaculada

2016-11-05

This study aims to extend the range of applications of tragacanth gum by studying its incorporation into bioplastics formulation, exploring the influence that different gum contents (0-20wt.%) exert over the thermomechanical and water uptake properties of bioplastics based on egg white albumen protein (EW). The effect of plasticizer nature was also evaluated through the modification of the water/glycerol ratio within the plasticizer fraction (fixed at 40wt.%). The addition of tragacanth gum generally yielded an enhancement of the water uptake capacity, being doubled at the highest content. Conversely, presence of tragacanth gum resulted in a considerable decrease in the bioplastic mechanical properties: both tensile strength and maximum elongation were reduced up to 75% approximately when compared to the gum-free system. Ageing of selected samples was also studied, revealing an important effect of storage time when tragacanth gum is present, possibly due to its hydrophilic character. Copyright © 2016 Elsevier Ltd. All rights reserved.

Thyroid uptake software

International Nuclear Information System (INIS)

Alonso, Dolores; Arista, Eduardo

2003-01-01

The DETEC-PC software was developed as a complement to a measurement system (hardware) able to perform Iodine Thyroid Uptake studies. The software was designed according to the principles of Object oriented programming using C++ language. The software automatically fixes spectrometric measurement parameters and besides patient measurement also performs statistical analysis of a batch of samples. It possesses a PARADOX database with all information of measured patients and a help system with the system options and medical concepts related to the thyroid uptake study

Tritiated water uptake kinetics in tissue-free water and organically-bound fractions of tomato plants

International Nuclear Information System (INIS)

Spencer, F.S.

1984-03-01

The kinetics of tritiated water (HTO) vapour uptake into tissue-free water tritium (TFWT) and organically bound tritium (OBT) fractions of tomato, Lycopersicon esculentum Mill., cv Vendor, were investigated under controlled growing conditions. Most uptake data fitted a first-order kinetic model, C t = C ∞ (1-e -kt ), where C t is the tritium concentration at time t, Ca the steady-state concentration and k the uptake rate constant. During atmospheric-HTO exposure with clean-water irrigation in open pots the TFWT k values were 0.024 ± 0.023 h -1 for new foliage, 0.104 ± 0.067 h -1 for old foliage and 0.042 ± to 0.136 h -1 for new green fruit. OBT uptake rate constants were 20 percent less for new foliage and 76 percent less for new green fruit. Under steady-state conditions the ratio of tritium specific activities of TWFT to atmospheric HTO were 0.43 in new foliage, 0.46 in old foliage and 0.19 in green fruit. Within the plant, OBT and TFWT ratios were 0.70 for new foliage, 0.63 for old foliage (maximum) and between 0.72 and 1.92 for green fruit. The greater than unity tritium specific activity ratios in green fruit were not attributed to tritium enrichment but rather to the translocation of foliar OBT to the growing fruit which contained lower specific activity TFWT derived from soil water

18F-FET and 18F-FCH uptake in human glioblastoma T98G cell lines

International Nuclear Information System (INIS)

Persico, Marco Giovanni; Buroni, Federica Eleonora; Pasi, Francesca; Lodola, Lorenzo; Aprile, Carlo; Nano, Rosanna; Hodolic, Marina

2016-01-01

Despite complex treatment of surgery, radiotherapy and chemotherapy, high grade gliomas often recur. Differentiation between post-treatment changes and recurrence is difficult. 18 F-methyl-choline ( 18 F-FCH) is frequently used in staging and detection of recurrent prostate cancer disease as well as some brain tumours; however accumulation in inflammatory tissue limits its specificity. The 18 F-ethyl-tyrosine ( 18 F-FET) shows a specific uptake in malignant cells, resulting from increased expression of amino acid transporters or diffusing through the disrupted blood-brain barrier. 18 F-FET exhibits lower uptake in machrophages and other inflammatory cells. Aim of this study was to evaluate 18 F-FCH and 18 F-FET uptake by human glioblastoma T98G cells. Human glioblastoma T98G or human dermal fibroblasts cells, seeded at a density to obtain 2 × 10 5 cells per flask when radioactive tracers were administered, grew adherent to the plastic surface at 37°C in 5% CO 2 in complete medium. Equimolar amounts of radiopharmaceuticals were added to cells for different incubation times (20 to 120 minutes) for 18 F-FCH and 18 F-FET respectively. The cellular radiotracer uptake was determined with a gamma counter. All experiments were carried out in duplicate and repeated three times. The uptake measurements are expressed as the percentage of the administered dose of tracer per 2 × 10 5 cells. Data (expressed as mean values of % uptake of radiopharmaceuticals) were compared using parametric or non-parametric tests as appropriate. Differences were regarded as statistically significant when p<0.05. A significant uptake of 18 F-FCH was seen in T98G cells at 60, 90 and 120 minutes. The percentage uptake of 18 F-FET in comparison to 18 F-FCH was lower by a factor of more than 3, with different kinetic curves. 18 F-FET showed a more rapid initial uptake up to 40 minutes and 18 F-FCH showed a progressive rise reaching a maximum after 90 minutes. 18 F-FCH and 18 F-FET are candidates

Furosemide diminishes 18F-fluoroethylcholine uptake in prostate cancer in vivo

International Nuclear Information System (INIS)

Rischke, H.C.; Beck, Teresa; Wieser, Gesche; Meyer, Philipp T.; Vach, Werner; Grosu, Anca L.; Schultze-Seemann, Wolfgang; Jilg, Cordula A.

2014-01-01

18 F-Fluoroethylcholine ( 18 F-FECh) is excreted via the urinary system with high activity accumulation in the urinary bladder. Furosemide and oral hydration can be administered concomitantly to reduce urinary activity to provide better detectability of retroperitoneal and pelvic lesions. Currently it is unknown if there is any effect of furosemide on 18 F-FECh uptake in organs, tissues and tumour lesions and the extent to which image quality along the urinary tract may be improved by furosemide. We retrospectively analysed 217 18 F-FECh PET/CT examinations from 213 patients with known prostate cancer (PCa), performed either with oral hydration (109) or furosemide 20 mg together with oral hydration (108). Maximum 18 F-FECh uptake in different organs, tissues, lymph nodes and osseous metastases was quantified in terms of standardized uptake value (SUV) in a volume of interest and compared between the two groups. To characterize the impact of furosemide on lesion detectability a three-point rating scale was used to assess the presence of focal activity spots in the ureters and of perivesicular artefacts. Patient characteristics and distribution of tumour lesions were well balanced between the two groups. Overall, SUVmax values from normal organs were increased after furosemide compared to the values in patients scanned without furosemide. Significant changes were observed in the salivary glands, liver, spleen, pancreas, kidneys, gluteus muscle and perirenal fat. SUVmax values were significantly decreased after furosemide in lymph node metastases (SUVmax 4.81 ± 2.68 vs. 6.48 ± 4.22, p = 0.0006), but not in osseous metastases. Evaluation of image quality along the urinary tract revealed significantly better depiction of the perivesicular space and significantly less focal tracer accumulation in the ureters in patients receiving furosemide, but the number of detected lymph nodes was not significantly different. Furosemide administration reduced choline uptake in

Physiological FDG uptake in the palatine tonsils

International Nuclear Information System (INIS)

Kawabe, Joji; Okamura, Terue; Shakudo, Miyuki

2001-01-01

In clinical F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) studies of the head and neck region, remarkable symmetric tonsillar FDG uptake is sometimes observed. We determined the incidence and degree of tonsillar FDG uptake and investigated the significance of tonsillar FDG uptake. Between June 1998 and August 1998, we obtained informed consent from 17 patients who were scheduled to undergo a FDG-PET study for their own disease (11 men and 6 women; aged 22 to 77 yr) and who did not have head and neck disease to perform FDG-PET scanning of the head and neck region in addition to their target organs. The incidence and degree of tonsillar FDG uptake were determined. Remarkable tonsillar FDG uptake was found in 9 patients. The SUVs of these FDG uptakes ranged from 2.48 to 6.75, with a mean of 4.29±1.20 (SD). Tonsillar FDG uptakes in the remaining 8 patients were not remarkable, and their SUVs ranged from 1.93 to 3.31, with a mean of 2.46±0.45. Head and neck disease does not appear to have been responsible for the increase in tonsillar FDG uptake. Differences among tonsillar FDG uptake in these 17 patients without head and neck disease appear to reflect differences in activity of ''physiological'' inflammation of the palatine tonsils. (author)

The effect of iodine uptake on radiation dose absorbed by patient tissues in contrast enhanced CT imaging. Implications for CT dosimetry

Energy Technology Data Exchange (ETDEWEB)

Perisinakis, Kostas; Damilakis, John [University of Crete, Department of Medical Physics, Medical School, Heraklion, Crete (Greece); University Hospital of Heraklion, Department of Medical Physics, Heraklion, Crete (Greece); Tzedakis, Antonis; Papadakis, Antonios E. [University Hospital of Heraklion, Department of Medical Physics, Heraklion, Crete (Greece); Spanakis, Kostas [University Hospital of Heraklion, Department of Radiology, Heraklion, Crete (Greece); Hatzidakis, Adam [University Hospital of Heraklion, Department of Radiology, Heraklion, Crete (Greece); University of Crete, Department of Radiology, Medical School, Heraklion, Crete (Greece)

2018-01-15

To investigate the effect of iodine uptake on tissue/organ absorbed doses from CT exposure and its implications in CT dosimetry. The contrast-induced CT number increase of several radiosensitive tissues was retrospectively determined in 120 CT examinations involving both non-enhanced and contrast-enhanced CT imaging. CT images of a phantom containing aqueous solutions of varying iodine concentration were obtained. Plots of the CT number increase against iodine concentration were produced. The clinically occurring iodine tissue uptake was quantified by attributing recorded CT number increase to a certain concentration of aqueous iodine solution. Clinically occurring iodine uptake was represented in mathematical anthropomorphic phantoms. Standard 120 kV CT exposures were simulated using Monte Carlo methods and resulting organ doses were derived for non-enhanced and iodine contrast-enhanced CT imaging. The mean iodine uptake range during contrast-enhanced CT imaging was found to be 0.02-0.46% w/w for the investigated tissues, while the maximum value recorded was 0.82% w/w. For the same CT exposure, iodinated tissues were found to receive higher radiation dose than non-iodinated tissues, with dose increase exceeding 100% for tissues with high iodine uptake. Administration of iodinated contrast medium considerably increases radiation dose to tissues from CT exposure. (orig.)

Hydrogen uptake by Azolla-Anabaena

International Nuclear Information System (INIS)

Ruschel, A.P.; Freitas, J.R. de; Silva, P.M.

1984-01-01

The hydrogen uptake in the Azolla-Anabaena system is studied. Tritium is used as tracer. Plants are incubated under different atmosphere composition: a) Air + 3 H 2 ; b) Air + CO 2 + 3 H 2 + CO; c) Air + 3 H 2 + CO; d) Air + CO 2 + 3 H 2 + CO to study the pathway of absorbed hydrogen in the Azolla - Anabaena system. Azolla-Anabaena showed greater hydrogen uptake under argonium atmosphere than under air. Carbon monoxide decreased hydrogen uptake. There are evidences of recycling of the hydrogen evolved through notrogenease. (Author) [pt

Uptake and transport of positron-emitting tracer in plants

Energy Technology Data Exchange (ETDEWEB)

Kume, Tamikazu; Matsuhashi, Shinpei; Shimazu, Masamitsu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; and others

1997-03-01

The transport of a positron-emitting isotope introduced into a plant was dynamically followed by a special observation apparatus called `Positron-Emitting Tracer Imaging System`. In the system, annihilation {gamma}-rays from the positron emitter are detected with two planer detectors (5 x 6 cm square). The water containing ca. 5 MBq/ml of {sup 18}F was fed to the cut stem of soybean for 2 min and then the images of tracer activity were recorded for 30 - 50 min. When the midrib of a leaf near the petiole was cut just before measurement, the activity in the injured leaf was decreased but detected even at the apex. This result suggests that the damaged leaf recovered the uptake of water through the lamina. Maximum tracer activities in leaves of unirradiated plant were observed within 10 min, whereas those of irradiated plant at 100 Gy were observed after over 25 min. The final activity of irradiated plant after 30 min was lower than that of unirradiated plant. In case of beans, there was a difference in the absorption behavior of the {sup 18}F-labeled water between unirradiated and irradiated samples. These results show that the system is effective to observe the uptake and transportation of water containing positron emitting tracer for the study of damage and recovery functions of plants. (author)

Transition of unsteady velocity profiles with reverse flow

Science.gov (United States)

Das, Debopam; Arakeri, Jaywant H.

1998-11-01

This paper deals with the stability and transition to turbulence of wall-bounded unsteady velocity profiles with reverse flow. Such flows occur, for example, during unsteady boundary layer separation and in oscillating pipe flow. The main focus is on results from experiments in time-developing flow in a long pipe, which is decelerated rapidly. The flow is generated by the controlled motion of a piston. We obtain analytical solutions for laminar flow in the pipe and in a two-dimensional channel for arbitrary piston motions. By changing the piston speed and the length of piston travel we cover a range of values of Reynolds number and boundary layer thickness. The velocity profiles during the decay of the flow are unsteady with reverse flow near the wall, and are highly unstable due to their inflectional nature. In the pipe, we observe from flow visualization that the flow becomes unstable with the formation of what appears to be a helical vortex. The wavelength of the instability [simeq R: similar, equals]3[delta] where [delta] is the average boundary layer thickness, the average being taken over the time the flow is unstable. The time of formation of the vortices scales with the average convective time scale and is [simeq R: similar, equals]39/([Delta]u/[delta]), where [Delta]u=(umax[minus sign]umin) and umax, umin and [delta] are the maximum velocity, minimum velocity and boundary layer thickness respectively at each instant of time. The time to transition to turbulence is [simeq R: similar, equals]33/([Delta]u/[delta]). Quasi-steady linear stability analysis of the velocity profiles brings out two important results. First that the stability characteristics of velocity profiles with reverse flow near the wall collapse when scaled with the above variables. Second that the wavenumber corresponding to maximum growth does not change much during the instability even though the velocity profile does change substantially. Using the results from the experiments and the

Cancer cell uptake behavior of Au nanoring and its localized surface plasmon resonance induced cell inactivation

International Nuclear Information System (INIS)

Chu, Che-Kuan; Tu, Yi-Chou; Chang, Yu-Wei; Chu, Chih-Ken; Chen, Shih-Yang; Chi, Ting-Ta; Kiang, Yean-Woei; Yang, Chih-Chung

2015-01-01

Au nanorings (NRIs), which have the localized surface plasmon resonance (LSPR) wavelength around 1058 nm, either with or without linked antibodies, are applied to SAS oral cancer cells for cell inactivation through the LSPR-induced photothermal effect when they are illuminated by a laser of 1065 nm in wavelength. Different incubation times of cells with Au NRIs are considered for observing the variations of cell uptake efficiency of Au NRI and the threshold laser intensity for cell inactivation. In each case of incubation time, the cell sample is washed for evaluating the total Au NRI number per cell adsorbed and internalized by the cells based on inductively coupled plasma mass spectrometry measurement. Also, the Au NRIs remaining on cell membrane are etched with KI/I 2 solution to evaluate the internalized Au NRI number per cell. The threshold laser intensities for cell inactivation before washout, after washout, and after KI/I 2 etching are calibrated from the circular area sizes of inactivated cells around the illuminated laser spot center with various laser power levels. By using Au NRIs with antibodies, the internalized Au NRI number per cell increases monotonically with incubation time up to 24 h. However, the number of Au NRI remaining on cell membrane reaches a maximum at 12 h in incubation time. The cell uptake behavior of an Au NRI without antibodies is similar to that with antibodies except that the uptake NRI number is significantly smaller and the incubation time for the maximum NRI number remaining on cell membrane is delayed to 20 h. By comparing the threshold laser intensities before and after KI/I 2 etching, it is found that the Au NRIs remaining on cell membrane cause more effective cancer cell inactivation, when compared with the internalized Au NRIs. (paper)

Maximum permissible dose

International Nuclear Information System (INIS)

Anon.

1979-01-01

This chapter presents a historic overview of the establishment of radiation guidelines by various national and international agencies. The use of maximum permissible dose and maximum permissible body burden limits to derive working standards is discussed

Change of Maximum Standardized Uptake Value Slope in Dynamic Triphasic [18F]-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Distinguishes Malignancy From Postradiation Inflammation in Head-and-Neck Squamous Cell Carcinoma: A Prospective Trial

International Nuclear Information System (INIS)

Anderson, Carryn M.; Chang, Tangel; Graham, Michael M.; Marquardt, Michael D.; Button, Anna; Smith, Brian J.; Menda, Yusuf; Sun, Wenqing; Pagedar, Nitin A.; Buatti, John M.

2015-01-01

Purpose: To evaluate dynamic [ 18 F]-fluorodeoxyglucose (FDG) uptake methodology as a post–radiation therapy (RT) response assessment tool, potentially enabling accurate tumor and therapy-related inflammation differentiation, improving the posttherapy value of FDG–positron emission tomography/computed tomography (FDG-PET/CT). Methods and Materials: We prospectively enrolled head-and-neck squamous cell carcinoma patients who completed RT, with scheduled 3-month post-RT FDG-PET/CT. Patients underwent our standard whole-body PET/CT scan at 90 minutes, with the addition of head-and-neck PET/CT scans at 60 and 120 minutes. Maximum standardized uptake values (SUV max ) of regions of interest were measured at 60, 90, and 120 minutes. The SUV max slope between 60 and 120 minutes and change of SUV max slope before and after 90 minutes were calculated. Data were analyzed by primary site and nodal site disease status using the Cox regression model and Wilcoxon rank sum test. Outcomes were based on pathologic and clinical follow-up. Results: A total of 84 patients were enrolled, with 79 primary and 43 nodal evaluable sites. Twenty-eight sites were interpreted as positive or equivocal (18 primary, 8 nodal, 2 distant) on 3-month 90-minute FDG-PET/CT. Median follow-up was 13.3 months. All measured SUV endpoints predicted recurrence. Change of SUV max slope after 90 minutes more accurately identified nonrecurrence in positive or equivocal sites than our current standard of SUV max ≥2.5 (P=.02). Conclusions: The positive predictive value of post-RT FDG-PET/CT may significantly improve using novel second derivative analysis of dynamic triphasic FDG-PET/CT SUV max slope, accurately distinguishing tumor from inflammation on positive and equivocal scans

Uptake of benzyladenine by excised watermelon cotyledons.

Science.gov (United States)

Lampugnani, M G; Fantelli, R; Longo, G P; Longo, C P; Rossi, G

1981-07-01

The uptake of 8-[(14)C]N(6)-benzyladenine (BA) was studied in excised watermelon (Citrullus vulgaris Schrad.) cotyledons 24 hours after the start of imbibition. The passive nature of this uptake is suggested by the following evidence: (a) no sign of saturation on increasing external concentration of BA; (b) no decrease in uptake under conditions that inhibit ATP synthesis; (c) no change in amount of radioactivity absorbed when cotyledons are frozen and thawed before the uptake test. About two-thirds of the radioactivity taken up is released after 12 hours of washing. If the washing is performed at 2 C very little radioactivity is released.There seems to be a correlation between the level of radioactivity (i.e. of BA + derivatives) present in the cotyledons and the magnitude of hormonal responses that are observed four days after uptake. This relationship holds regardless of whether a given level of radioactivity has been reached after a short period of uptake or after a long period of uptake followed by washing.

Iodine capsules in thyroid therapy: An individually controlled study of I-131 uptake kinetics as compared to liquid administration

International Nuclear Information System (INIS)

von Schulthess, G.K.; Seelentag, W.W.; Pfeiffer, G.; Blauenstein, P.; Bekier, A.

1984-01-01

The aim of this study was to determine the additional radiation dose sustained by parts of the patients gastric mucosa when given I-131 therapy in capsular rather than liquid form, and thus to establish the safety of this procedure. 16 patients with benign thyroid disease were studied by measuring serum radioactivity at 0, 5, 10, 20, 40, and 80 min. after administration of the capsule (120-200 MBq I131). These serum uptake values were compared to the uptake after administration of a liquid diagnostic dose of I-131 (2 MBq). From the resulting uptake curves the delay due to capsular dissolution was determined. The average dissolution time was found to be 12 min. with a large standard deviation of 7 min. Also, a theoretical curve was computed to indicate the dose rate as a function of the distance from the surface of the capsule. Based on this information the maximum dose to the gastric mucosa is of the order of 250 cGy for a therapeutic activity of 185 MBq, which is the maximum dose which may be given as single application to outpatients in Switzerland. By having the patient swallow some liquid during the first ten minutes, the capsule can be made to move around, and hence, the local radiation dose can be reduced substantially. The authors conclude, that I-131 in capsular form is a safe galenic form for therapeutic use in patients with thyroid disease. When large doses are given, administration of the dose in several capsules may be advisable

The effects of a pilates-aerobic program on maximum exercise capacity of adult women

Directory of Open Access Journals (Sweden)

Milena Mikalački

Full Text Available ABSTRACT Introduction: Physical exercise such as the Pilates method offers clinical benefits on the aging process. Likewise, physiologic parameters may be improved through aerobic exercise. Methods: In order to compare the differences of a Pilates-Aerobic intervention program on physiologic parameters such as the maximum heart rate (HRmax, relative maximal oxygen consumption (relative VO2max and absolute (absolute VOmax, maximum heart rate during maximal oxygen consumption (VO2max-HRmax, maximum minute volume (VE and forced vital capacity (FVC, a total of 64 adult women (active group = 48.1 ± 6.7 years; control group = 47.2 ± 7.4 years participated in the study. The physiological parameters, the maximal speed and total duration of test were measured by maximum exercise capacity testing through Bruce protocol. The HRmax was calculated by a cardio-ergometric software. Pulmonary function tests, maximal speed and total time during the physical test were performed in a treadmill (Medisoft, model 870c. Likewise, the spirometry analyzed the impact on oxygen uptake parameters, including FVC and VE. Results: The VO2max (relative and absolute, VE (all, P<0.001, VO2max-HRmax (P<0.05 and maximal speed of treadmill test (P<0.001 showed significant difference in the active group after a physical exercise interventional program. Conclusion: The present study indicates that the Pilates exercises through a continuous training program might significantly improve the cardiovascular system. Hence, mixing strength and aerobic exercises into a training program is considered the optimal mechanism for healthy aging.

Gastric gallium-67 uptake in gastritis

International Nuclear Information System (INIS)

Yeh, E.L.; Tisdale, P.L.; Zielonka, J.S.

1983-01-01

Even though Ga-67 imaging has been used widely in the diagnosis of malignant as well as inflammatory lesions, its uptake in the stomach has been reported in the literature mainly in gastric lymphoma and carcinoma. As shown in this case, intense gastric uptake of the radionuclide may be seen in common gastritis without malignancy. Perhaps the benign gastric uptake of Ga-67 deserves more emphasis

Effect of Na, Ca and pH on simultaneous uptake of Cd, Cu, Ni, Pb, and Zn in the water flea Daphnia magna measured using stable isotopes

International Nuclear Information System (INIS)

Komjarova, I.; Blust, R.

2009-01-01

The present study investigates the effects of Na + , Ca 2+ and pH on the kinetics of Cd, Cu, Ni, Pb, and Zn uptake in Daphnia magna at low exposure concentrations measured using a stable isotope technique. Using experimental data the uptake rate constants were calculated for each metal individually on the basis of total metal concentrations. The copper uptake was not significantly affected by variations in chemical composition of the test medium. Calcium had a suppressing effect on the uptake of Cd, Ni, Pb and Zn. Specifically, Cd and Ni uptake rate constants decreased with increases in calcium concentrations from 0.1 to 2.5 mM. The uptake of Zn and Pb was significantly suppressed only at 2.5 mM Ca. The effect of sodium was less clear. There was no effect of varying sodium concentrations on the Ni uptake rate constants. Cd and Pb showed an increase in uptake rate constants at elevated sodium concentrations (2-8 mM Na + for Cd and 8 mM Na + for Pb). A bell-shaped response on increasing Na + concentrations was observed for Zn with a maximum value of uptake rate constant at the middle value (2 mM Na + ). Variation in pH of the medium affected Cd, Ni and Zn uptake processes. When Daphnia were exposed to acidic conditions (pH 6), the Cd and Ni uptake rate constants were the highest, while similarly low values were observed at neutral and basic conditions. In contrast, the uptake rates of Zn were linearly increasing with increasing pH of the medium.

Uptake of [3H]vitamin D3 from low and high density lipoproteins by cultured human fibroblasts

International Nuclear Information System (INIS)

Shireman, R.B.; Williams, D.; Remsen, J.F.

1986-01-01

The plasma distribution and cellular uptake of [ 3 H]vitamin D 3 was studied in vitro using cultured human fibroblasts. Incubation of [ 3 H]vitamin D 3 (cholecalciferol) with plasma followed by sequential ultracentrifugal fractionation of the lipoproteins indicated that 2-4% of the radioactivity associated with the very low density lipoprotein (VLDL), 12% with low density lipoprotein (LDL), and approximately 60% with the high density lipoprotein (HDL). The remaining radioactivity, 25%, was associated with the sedimented plasma fractions. By comparison, an average of 86% of the radioactivity from [ 3 H] 1,25-dihydroxycholecalciferol associated with the sedimented plasma fractions. The uptake of [ 3 H]vitamin D 3 from plasma, LDL, or HDL was studied in cultured human cells; uptake by normal fibroblasts was greatest from LDL and least from plasma. The cellular association of vitamin D 3 was time, concentration, and temperature dependent. At a concentration of 50 μg LDL/ml of medium, the uptake of [ 3 H]vitamin D 3 from LDL at 37 0 C was rapid and reached a maximum at approximately 4 hr; it was slower from HDL but continued to increase slowly up to 24 hr. The significance of these in vitro findings is uncertain since much of the vitamin D 3 absorbed from the intestine reportedly associates with chylomicrons and is rapidly taken up by the liver

Dopamine Release and Uptake Impairments and Behavioral Alterations Observed in Mice that Model Fragile X Mental Retardation Syndrome.

Science.gov (United States)

Fulks, Jenny L; O'Bryhim, Bliss E; Wenzel, Sara K; Fowler, Stephen C; Vorontsova, Elena; Pinkston, Jonathan W; Ortiz, Andrea N; Johnson, Michael A

2010-10-20

In this study we evaluated the relationship between amphetamine-induced behavioral alterations and dopamine release and uptake characteristics in Fmr1 knockout (Fmr1 KO) mice, which model fragile X syndrome. The behavioral analyses, obtained at millisecond temporal resolution and 2 mm spatial resolution using a force-plate actometer, revealed that Fmr1 KO mice express a lower degree of focused stereotypy compared to wild type (WT) control mice after injection with 10 mg/kg (ip) amphetamine. To identify potentially related neurochemical mechanisms underlying this phenomenon, we measured electrically-evoked dopamine release and uptake using fast-scan cyclic voltammetry at carbon-fiber microelectrodes in striatal brain slices. At 10 weeks of age, dopamine release per pulse, which is dopamine release corrected for differences in uptake, was unchanged. However, at 15 (the age of behavioral testing) and 20 weeks of age, dopamine per pulse and the maximum rate of dopamine uptake was diminished in Fmr1 KO mice compared to WT mice. Dopamine uptake measurements, obtained at different amphetamine concentrations, indicated that dopamine transporters in both genotypes have equal affinities for amphetamine. Moreover, dopamine release measurements from slices treated with quinpirole, a D2-family receptor agonist, rule out enhanced D2 autoreceptor sensitivity as a mechanism of release inhibition. However, dopamine release, uncorrected for uptake and normalized against the corresponding pre-drug release peaks, increased in Fmr1 KO mice, but not in WT mice. Collectively, these data are consistent with a scenario in which a decrease in extracellular dopamine levels in the striatum result in diminished expression of focused stereotypy in Fmr1 KO mice.

Difference in F-18 FDG uptake after esophago gastroduodenoscopy and colonoscopy in healthy sedated subjects

Energy Technology Data Exchange (ETDEWEB)

Oh, Jong Ryool; Chang, Woo Jin; Bae, Seung Il; Song, In Wook; Bong, Jin Gu; Jeong, Hye Yeon; Park, So Young; Bae, Jeong Yup; Yoon, Hyun Dae [Raphael Hospital, Daegu (Korea, Republic of); Seo, Ji Hyoung [Dept. of Nuclear MedicineFatima Hospital, Daegu (Korea, Republic of)

2017-09-15

We aimed to evaluate the difference in fluorodeoxyglucose (FDG) uptake in sedated healthy subjects after they underwent esophagogastroduodenoscopy (EGD) and colonoscopy procedures. The endoscopy group (n = 29) included healthy subjects who underwent screening via F-18 FDG positron emission tomography/computed tomography (PET/CT) after an EGD and/or colonoscopy under sedation on the same day. The control group (n = 35) included healthy subjects who underwent screening via PET/CT only. FDG uptake in the tongue, uvula, epiglottis, vocal cords, esophagus, stomach, duodenum, liver, cecum, colon, anus, and muscle were compared between the two groups. Maximum standardized uptake value (SUVmax) in the tongue, pharynx, larynx, and esophagus did not significantly differ between the endoscopy and control groups. In contrast, mean SUVmax in the whole stomach was 18 % higher in the endoscopy group than in the control group (SUVmax: 2.96 vs. 2.51, P = 0.010). In the lower gastrointestinal track, SUVmax from the cecum to the rectum was not significantly different between the two groups, whereas SUVmax in the anus was 20 % higher in the endoscopy group than in the control group (SUVmax: 4.21 vs. 3.50, P = 0.002). SUVmax in the liver and muscle was not significantly different between the two groups. Mean volume of the stomach and mean cross section of the colon was significantly higher in the endoscopy group than in the control group (stomach: 313.28 cm{sup 3} vs. 209.93 cm{sup 3}, P < 0.001, colon: 8.82 cm{sup 2} vs. 5.98 cm{sup 2}, P = 0.001). EGD and colonoscopy under sedation does not lead to significant differences in SUVmax in most parts of the body. Only gastric FDG uptake in the EGD subjects and anal FDG uptake in the colonoscopy subjects was higher than uptake in those regions in the control subjects.

21 CFR 862.1715 - Triiodothyronine uptake test system.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Triiodothyronine uptake test system. 862.1715... Systems § 862.1715 Triiodothyronine uptake test system. (a) Identification. A triiodothyronine uptake test... plasma. Measurements of triiodothyronine uptake are used in the diagnosis and treatment of thyroid...

Uptake of myocardial imaging agents by rejected hearts

International Nuclear Information System (INIS)

Bergsland, J.; Carr, E.A.; Carroll, M.; Wright, J.W.; Feldman, M.J.; Massucci, J.; Bhayana, J.N.; Gona, J.M.

1985-01-01

Technetium 99 m pyrophosphate, Gallium 67 and Thallium 201 uptakes were measured in heterotopically transplanted rat hearts. Five days after transplantation, Technetium 99 m pyrophosphate, and Gallium 67 uptakes were significantly higher in allogeneic grafts than in syngeneic grafts. At an early stage of rejection (three days after transplantation), only Technetium 99 m pyrophosphate uptake in the left ventricle of allogeneic grafts showed a significant difference (p less than 0.04). At five days, Thallium 201 uptake was significantly lower in allo- than syngeneic grafts. There was a positive correlation between radionuclide uptake and histologic degree of rejection for Technetium 99 m pyrophosphate and Gallium 67 while Thallium 201 uptake correlated negatively. Analysis of variance revealed that hearts with no or minimal rejection had statistically different uptakes than hearts with mild to moderate rejection. These results suggest that uptake of imaging agents might be useful in the diagnosis of rejection of the transplanted heart

Correlation of high 18F-FDG uptake to clinical, pathological and biological prognostic factors in breast cancer

International Nuclear Information System (INIS)

Groheux, David; Moretti, Jean-Luc; Hindie, Elif; Giacchetti, Sylvie; Espie, Marc; Hamy, Anne-Sophie; Cuvier, Caroline; Porcher, Raphael; Lehmann-Che, Jacqueline; Roquancourt, Anne de; Vercellino, Laetitia

2011-01-01

The aim of this study was to determine the impact of the main clinicopathological and biological prognostic factors of breast cancer on 18 F-fluorodeoxyglucose (FDG) uptake. Only women with tumours larger than 20 mm (T2-T4) were included in order to minimize bias of partial volume effect. In this prospective study, 132 consecutive women received FDG PET/CT imaging before starting neoadjuvant chemotherapy. Maximum standardized uptake values (SUV max ) were compared to tumour characteristics as assessed on core biopsy. There was no influence of T and N stage on SUV. Invasive ductal carcinoma showed higher SUV than lobular carcinoma. However, the highest uptake was found for metaplastic tumours, representing 5% of patients in this series. Several biological features usually considered as bad prognostic factors were associated with an increase in FDG uptake: the median of SUV max was 9.7 for grade 3 tumours vs 4.8 for the lower grades (p < 0.0001); negativity for oestrogen receptors (ER) was associated with higher SUV (ER+ SUV = 5.5; ER- SUV = 7.6; p = 0.003); triple-negative tumours (oestrogen and progesterone receptor negative, no overexpression of c-erbB-2) had an SUV of 9.2 vs 5.8 for all others (p = 0005); p53 mutated tumours also had significantly higher SUV (7.8 vs 5.0; p < 0.0001). Overexpression of c-erbB-2 had no effect on the SUV value. Knowledge of the factors influencing uptake is important when interpreting FDG PET/CT scans. Also, findings that FDG uptake is highest in those patients with poor prognostic features (high grade, hormone receptor negativity, triple negativity, metaplastic tumours) is helpful to determine who are the best candidates for baseline staging. (orig.)

Uptake and transport of chromium in plants

International Nuclear Information System (INIS)

Ramachandran, V.; D'souza, T.J.; Mistry, K.B.

1980-01-01

The uptake of chromium, an important soil and water pollutant, by five different plant species was examined in nutrient culture experiments using chromium-51 as a tracer. The concentration in aerial tissues of both trivalent and hexavalent forms of chromium was the greatest in peas followed by beans, tomato and the cereals over identical uptake periods. The uptake of 51 Cr 3+ was, in general, greater than 51 CrO 4 2- . Studies with bean plants indicated that shoot uptake of both forms of chromium decreased with increasing pH and salt concentration of the external solution. Concentrations of 10 -4 M and 10 -5 M DNP inhibited 51 Cr uptake by bean shoots. (author)

The distribution of FDG at PET examinations constitutes a relative mechanism: significant effects at activity quantification in patients with a high muscular uptake

International Nuclear Information System (INIS)

Lindholm, Henry; Johansson, Ove; Jacobsson, Hans; Jonsson, Cathrine

2012-01-01

At 18 F-2-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) examinations a high tracer uptake of the skeletal muscles is sometimes encountered which can lead to reduced uptake in pathological lesions. This was evaluated in retrospect in patients being recalled for a repeat examination after reducing the muscular uptake. Ten patients with increased muscular tracer uptake were examined with FDG PET/CT on two occasions with a mean of 6 days. All patients showed at least one pathological lesion with increased tracer uptake. The muscular uptake was reduced at the second examination by informing the patient to refrain from physical activity together with pretreatment with diazepam. The maximum standardized uptake value (SUV max ) of the pathological lesion and SUV mean of certain skeletal muscles, liver, spleen, lungs, blood and certain bone marrow portions were calculated. In all patients, the muscular uptake was reduced to a normal level at visual evaluation as well as at comparison of SUVs with 25 consecutive clinical patients exhibiting a normal FDG distribution (p max increased from 2.4 to 3.7 (54 %) between the examinations (p max to the activity of any of the reference tissues/organs there was no significant difference between the studies. The distribution of FDG constitutes a relative mechanism. This must be especially considered at longitudinal examinations in the same patient at therapy evaluations. In examinations with a somehow distorted general distribution of the activity, it may be more relevant to relate the lesion activity to a reference tissue/organ than relying on SUV assessments. (orig.)

Radioiodine uptake measurements in thyroid

International Nuclear Information System (INIS)

Kadireshn, A.; Kapur, S.C.; Samuel, J.R.; Mahajan, M.K.

1988-01-01

Evaluation of thyroid function can be carried out by measuring the uptake of orally administered radioactive iodine. The results of the thyroid uptake measurements for the period 1982-1987 in Christian Medical College, Ludhiana are presented here. About 3000 patients were screened during the analysis period. (author)

Octreotide Uptake in Parathyroid Adenoma

Directory of Open Access Journals (Sweden)

Seyhan Karaçavuş

2012-08-01

Full Text Available The patient with a history of bone pain and muscle weakness, was thought to have oncogenic osteomalacia as a result of biochemical investigations and directed to Nuclear Medicine Department for a whole-body bone scintigraphy and 111In-octreotide scintigraphy. There was no focal pathologic tracer uptake, but generalized marked increase in skeletal uptake on bone scintigraphy. Octreotide scintigraphy showed accumulation of octreotide in the region of the left lobe of the thyroid gland in the neck. Thereafter, parathyroid scintigraphy was performed with technetium-99m labeled metroxy-isobutyl-isonitryl (99mTc-MIB and MIBI scan demonstrated radiotracer uptake at the same location with octreotide scintigraphy. The patient underwent left inferior parathyroidectomy and histopathology confirmed a parathyroid adenoma. Somatostatin receptor positive parathyroid adenoma may show octreotide uptake. Octreotide scintigraphy may be promising and indicate a possibility of using somatostatin analogues for the medical treatment of somatostatin receptor positive parathyroid tumors. (MIRT 2012;21:77-79

In vitro effects of toxaphene on mitochondrial calcium ATPase and calcium uptake in selected rat tissues

International Nuclear Information System (INIS)

Trottman, C.H.; Rao, K.S.P.; Morrow, W.; Uzodinma, J.E.; Desaiah, D.

1985-01-01

In vitro effects of toxaphene on Ca 2+ -ATPase activity and 45 Ca 2+ -uptake were studied in mitochondrial fractions of heart, kidney and liver tissues of rat. Mitochondrial fractions were prepared by the conventional centrifugation method. Ca 2+ -ATPase activity was determined by measuring the inorganic phosphate liberated during ATP hydrolysis. Toxaphene inhibited Ca 2+ -ATPase in a concentration dependent manner in all the three tissues. Substrate activation kinetics, with heart, kidney and liver tissue fractions, revealed that toxaphene inhibited Ca 2+ -ATPase activity non-competetively by decreasing the maximum velocity of the enzyme without affecting the enzyme-substrate affinity. Toxaphene also inhibited mitochondrial 45 Ca 2+ -uptake in the three selected tissues in a concentration dependent manner. These results indicate that toxaphene is an inhibitor of mitochondrial Ca 2+ -ATPase and calcium transport in heart, kidney and liver tissues of rat. 19 references, 5 figures

Use of gamma probe in {sup 131}I thyroid uptake studies; Utilizacao da sonda a cintilacao na captacao de {sup 131}I pela tireoide

Energy Technology Data Exchange (ETDEWEB)

Sarmento, Andrea Gondim Leitao

2002-11-01

Evaluation of thyroid uptake by administration of radioactive iodine is a well-defined procedure to assess patient thyroid function. In general, nuclear medicine institutions use gamma cameras coupled to pinhole collimators to perform uptake studies. With the growing use of intraoperative gamma probes in the radioguided surgical techniques, several institutions are purchasing this new and portable equipment, which can technically be also employed to assess patient's thyroid function, permitting further other applications of gamma cameras. The aim of the study was to compare thyroid uptake trails carried out with both gamma camera and intraoperative gamma probe, in order to evaluate the possible use of gamma probe for this purpose. At first a preliminary study of feasibility was carried out using a neck phantom to verify equipment efficiency with known activities of {sup 131} I. Henceforth, work data from 12 patients undergone studies of thyroid uptakes were evaluated, 24 hours after oral administration of 370 kBq of {sup 131} I. The maximum difference observed between the values obtained with both equipment was 60%, which demonstrated the feasibility of the proposed protocol and made clear that gamma probe can be useful for thyroid uptake studies. (author)

Use of gamma probe in {sup 131}I thyroid uptake studies; Utilizacao da sonda a cintilacao na captacao de {sup 131}I pela tireoide

Energy Technology Data Exchange (ETDEWEB)

Sarmento, Andrea Gondim Leitao

2002-11-01

Evaluation of thyroid uptake by administration of radioactive iodine is a well-defined procedure to assess patient thyroid function. In general, nuclear medicine institutions use gamma cameras coupled to pinhole collimators to perform uptake studies. With the growing use of intraoperative gamma probes in the radioguided surgical techniques, several institutions are purchasing this new and portable equipment, which can technically be also employed to assess patient's thyroid function, permitting further other applications of gamma cameras. The aim of the study was to compare thyroid uptake trails carried out with both gamma camera and intraoperative gamma probe, in order to evaluate the possible use of gamma probe for this purpose. At first a preliminary study of feasibility was carried out using a neck phantom to verify equipment efficiency with known activities of {sup 131} I. Henceforth, work data from 12 patients undergone studies of thyroid uptakes were evaluated, 24 hours after oral administration of 370 kBq of {sup 131} I. The maximum difference observed between the values obtained with both equipment was 60%, which demonstrated the feasibility of the proposed protocol and made clear that gamma probe can be useful for thyroid uptake studies. (author)

Sudden increase in atmospheric concentration reveals strong coupling between shoot carbon uptake and root nutrient uptake in young walnut trees

International Nuclear Information System (INIS)

Delaire, M.; Sigogne, M.; Beaujard, F.; Frak, E.; Adam, B.; Le Roux, X.

2005-01-01

Short-term effects of a sudden increase in carbon dioxide concentration on nutrient uptake by roots during vegetative growth was studied in young walnut trees. Rates of carbon dioxide uptake and water loss by individual trees were determined by a branch bag method from three days before and six days after carbon dioxide concentration was increased. Nutrient uptake rates were measured concurrently by a hydroponic recirculating nutrient solution system. Carbon dioxide uptake rates increased greatly with increasing atmospheric carbon dioxide; nutrient uptake rates were proportional to carbon dioxide uptake rates, except for the phosphorus ion. Daily water loss rates were only slightly affected by elevated carbon dioxide. Overall, it was concluded that in the presence of non-limiting supplies of water and nutrients, root nutrient uptake and shoot carbon assimilation are strongly coupled in the short term in young walnut trees despite the important carbon and nutrient storage capacities od woody species. 45 refs., 7 figs

Aquaporins and root water uptake

Science.gov (United States)

Water is one of the most critical resources limiting plant growth and crop productivity, and root water uptake is an important aspect of plant physiology governing plant water use and stress tolerance. Pathways of root water uptake are complex and are affected by root structure and physiological res...

Cell uptake survey of pegylated nanographene oxide.

Science.gov (United States)

Vila, M; Portolés, M T; Marques, P A A P; Feito, M J; Matesanz, M C; Ramírez-Santillán, C; Gonçalves, G; Cruz, S M A; Nieto, A; Vallet-Regi, M

2012-11-23

Graphene and more specifically, nanographene oxide (GO) has been proposed as a highly efficient antitumoral therapy agent. Nevertheless, its cell uptake kinetics, its influence in different types of cells and the possibility of controlling cellular internalization timing, is still a field that remains unexplored. Herein, different cell types have been cultured in vitro for several incubation periods in the presence of 0.075 mg ml(-1) pegylated GO solutions. GO uptake kinetics revealed differences in the agent's uptake amount and speed as a function of the type of cell involved. Osteoblast-like cells GO uptake is higher and faster without resulting in greater cell membrane damage. Moreover, the dependence on the commonly used PEG nature (number of branches) also influences the viability and cell uptake speed. These facts play an important role in the future definition of timing parameters and selective cell uptake control in order to achieve an effective therapy.

Cell uptake survey of pegylated nanographene oxide

International Nuclear Information System (INIS)

Vila, M; Nieto, A; Vallet-Regi, M; Portolés, M T; Feito, M J; Matesanz, M C; Ramírez-Santillán, C; Marques, P A A P; Gonçalves, G; Cruz, S M A

2012-01-01

Graphene and more specifically, nanographene oxide (GO) has been proposed as a highly efficient antitumoral therapy agent. Nevertheless, its cell uptake kinetics, its influence in different types of cells and the possibility of controlling cellular internalization timing, is still a field that remains unexplored. Herein, different cell types have been cultured in vitro for several incubation periods in the presence of 0.075 mg ml −1 pegylated GO solutions. GO uptake kinetics revealed differences in the agent’s uptake amount and speed as a function of the type of cell involved. Osteoblast-like cells GO uptake is higher and faster without resulting in greater cell membrane damage. Moreover, the dependence on the commonly used PEG nature (number of branches) also influences the viability and cell uptake speed. These facts play an important role in the future definition of timing parameters and selective cell uptake control in order to achieve an effective therapy. (paper)

In vivo quantification of {sup 18}F-Fdg uptake in human placenta during early pregnancy

Energy Technology Data Exchange (ETDEWEB)

Zanotti-Fregonara, P.; Jan, S.; Trebossen, R.; Maroy, R. [CEA, DSV, I2BM, SHFJ, F-91401 Orsay (France); Champion, C. [Univ Paul Verlaine Metz, Lab Phys Mol et Collis, Inst Phys, Metz (France); Hindie, E. [Hop St Antoine, AP-HP, F-75571 Paris (France); Hindie, E. [Univ Paris 07, IMDCT, IUH, Ecole Doctorale B2T, F-75221 Paris (France)

2008-07-01

{sup 18}F-FDG is the most widely used PET radiopharmaceutical. Nevertheless, no data for {sup 18}F-FDG uptake in the human placenta have been reported. We recently reported on embryo dosimetry in a woman who underwent an {sup 18}F-FDG PET/CT scan during early pregnancy. In the present work we attempt an in vivo quantification of the {sup 18}F-FDG uptake by the placenta. The 27-y-old woman received 320 MBq of {sup 18}F-FDG for a follow-up study for Hodgkin's lymphoma and was later discovered to be pregnant (embryo age 8 wk). Imaging started 1 h after injection. The maximum placental tissue uptake (SUVmax) was 2.5. This value was conservatively attributed to the entire placental volume, i.e., 45 mL, a value representative of the average dimensions of a normal placenta at 8 wk. On the basis of these measurements, placenta {sup 18}F-FDG uptake in our patient was 0.19% of the injected activity. A Monte Carlo simulation was used to derive the photon dose to the embryo from the placenta (0.022 * 10{sup -2} mGy per MBq of injected {sup 18}F-FDG) and from the surrounding amniotic fluid (0.017 * 10{sup -2} mGy MBq{sup -1}). This increases our previously calculated dose (3.3 * 10{sup -2} mGy MBq{sup -1}) by only a small fraction (1.18%), which does not justify modifying the previous estimate given the overall uncertainties. (authors)

99mTc-DPD uptake in juvenile arthritis

International Nuclear Information System (INIS)

Stender Hansen, E.; Holm, I.E.; Buenger, C.; Knudsen, V.; Noer, I.; Bach Christensen, S.

1986-01-01

Unilateral arthritis of the knee was induced in mongrel puppies by intraarticular injections of 1% Carragheenan. Bone metabolism was studied by a scintimetric technique on static 99m Tc-diphosphonate bone scans every 2nd week during the induction of arthritis for 3 months and monthly in a postarthritic phase of another 3 months. Changes in uptake of radionuclide were present after 2 weeks. The induction phase was characterized by a decreased uptake in the calcification layer of the juxta-articular growth plates and a moderately increased epiphyseal uptake. The postarthritic phase was characterized by normalization of growth plate uptake and a marked increase in epiphyseal uptake. Using contact autoradiography, the epiphyseal uptake was seen mainly in a narrow subchondral and subsynovial bone layer, around bone cysts and osteophytes, whereas central epiphyseal bone was osteopenic with decreased uptake of tracer. The study suggests that the early scintigraphic appearance of juvenile non-suppurative arthritis may be an overall decrease in uptake of 99m Tc-diphosphonate due to a depression of growth plate metabolism. (author)

Improving representation of nitrogen uptake, allocation, and carbon assimilation in the Community Land Model

Science.gov (United States)

Ghimire, B.; Riley, W. J.; Koven, C.

2013-12-01

Nitrogen is the most important nutrient limiting plant carbon assimilation and growth, and is required for production of photosynthetic enzymes, growth and maintenance respiration, and maintaining cell structure. The forecasted rise in plant available nitrogen through atmospheric nitrogen deposition and the release of locked soil nitrogen by permafrost thaw in high latitude ecosystems is likely to result in an increase in plant productivity. However a mechanistic representation of plant nitrogen dynamics is lacking in earth system models. Most earth system models ignore the dynamic nature of plant nutrient uptake and allocation, and further lack tight coupling of below- and above-ground processes. In these models, the increase in nitrogen uptake does not translate to a corresponding increase in photosynthesis parameters, such as maximum Rubisco capacity and electron transfer rate. We present an improved modeling framework implemented in the Community Land Model version 4.5 (CLM4.5) for dynamic plant nutrient uptake, and allocation to different plant parts, including leaf enzymes. This modeling framework relies on imposing a more realistic flexible carbon to nitrogen stoichiometric ratio for different plant parts. The model mechanistically responds to plant nitrogen uptake and leaf allocation though changes in photosynthesis parameters. We produce global simulations, and examine the impacts of the improved nitrogen cycling. The improved model is evaluated against multiple observations including TRY database of global plant traits, nitrogen fertilization observations and 15N tracer studies. Global simulations with this new version of CLM4.5 showed better agreement with the observations than the default CLM4.5-CN model, and captured the underlying mechanisms associated with plant nitrogen cycle.

Furosemide diminishes {sup 18}F-fluoroethylcholine uptake in prostate cancer in vivo

Energy Technology Data Exchange (ETDEWEB)

Rischke, H.C. [University of Freiburg, Department of Radiation Oncology, Freiburg (Germany); University of Freiburg, Department of Nuclear Medicine, Freiburg (Germany); Beck, Teresa; Wieser, Gesche; Meyer, Philipp T. [University of Freiburg, Department of Nuclear Medicine, Freiburg (Germany); Vach, Werner [University of Freiburg, Department of Clinical Epidemiology, Department of Medical Biometry and Medical Informatics, Freiburg (Germany); Grosu, Anca L. [University of Freiburg, Department of Radiation Oncology, Freiburg (Germany); Schultze-Seemann, Wolfgang; Jilg, Cordula A. [University of Freiburg, Department of Urology, Freiburg (Germany)

2014-11-15

{sup 18}F-Fluoroethylcholine ({sup 18}F-FECh) is excreted via the urinary system with high activity accumulation in the urinary bladder. Furosemide and oral hydration can be administered concomitantly to reduce urinary activity to provide better detectability of retroperitoneal and pelvic lesions. Currently it is unknown if there is any effect of furosemide on {sup 18}F-FECh uptake in organs, tissues and tumour lesions and the extent to which image quality along the urinary tract may be improved by furosemide. We retrospectively analysed 217 {sup 18}F-FECh PET/CT examinations from 213 patients with known prostate cancer (PCa), performed either with oral hydration (109) or furosemide 20 mg together with oral hydration (108). Maximum {sup 18}F-FECh uptake in different organs, tissues, lymph nodes and osseous metastases was quantified in terms of standardized uptake value (SUV) in a volume of interest and compared between the two groups. To characterize the impact of furosemide on lesion detectability a three-point rating scale was used to assess the presence of focal activity spots in the ureters and of perivesicular artefacts. Patient characteristics and distribution of tumour lesions were well balanced between the two groups. Overall, SUVmax values from normal organs were increased after furosemide compared to the values in patients scanned without furosemide. Significant changes were observed in the salivary glands, liver, spleen, pancreas, kidneys, gluteus muscle and perirenal fat. SUVmax values were significantly decreased after furosemide in lymph node metastases (SUVmax 4.81 ± 2.68 vs. 6.48 ± 4.22, p = 0.0006), but not in osseous metastases. Evaluation of image quality along the urinary tract revealed significantly better depiction of the perivesicular space and significantly less focal tracer accumulation in the ureters in patients receiving furosemide, but the number of detected lymph nodes was not significantly different. Furosemide administration reduced

Change of Maximum Standardized Uptake Value Slope in Dynamic Triphasic [{sup 18}F]-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Distinguishes Malignancy From Postradiation Inflammation in Head-and-Neck Squamous Cell Carcinoma: A Prospective Trial

Energy Technology Data Exchange (ETDEWEB)

Anderson, Carryn M., E-mail: carryn-anderson@uiowa.edu [Department of Radiation Oncology, University of Iowa, Iowa City, Iowa (United States); Chang, Tangel [Department of Radiation Oncology, University of Iowa, Iowa City, Iowa (United States); Graham, Michael M. [Department of Nuclear Medicine, University of Iowa, Iowa City, Iowa (United States); Marquardt, Michael D. [Department of Radiation Oncology, University of Iowa, Iowa City, Iowa (United States); Button, Anna; Smith, Brian J. [Department of Biostatistics, University of Iowa, Iowa City, Iowa (United States); Menda, Yusuf [Department of Nuclear Medicine, University of Iowa, Iowa City, Iowa (United States); Sun, Wenqing [Department of Radiation Oncology, University of Iowa, Iowa City, Iowa (United States); Pagedar, Nitin A. [Department of Otolaryngology—Head and Neck Surgery, University of Iowa, Iowa City, Iowa (United States); Buatti, John M. [Department of Radiation Oncology, University of Iowa, Iowa City, Iowa (United States)

2015-03-01

Purpose: To evaluate dynamic [{sup 18}F]-fluorodeoxyglucose (FDG) uptake methodology as a post–radiation therapy (RT) response assessment tool, potentially enabling accurate tumor and therapy-related inflammation differentiation, improving the posttherapy value of FDG–positron emission tomography/computed tomography (FDG-PET/CT). Methods and Materials: We prospectively enrolled head-and-neck squamous cell carcinoma patients who completed RT, with scheduled 3-month post-RT FDG-PET/CT. Patients underwent our standard whole-body PET/CT scan at 90 minutes, with the addition of head-and-neck PET/CT scans at 60 and 120 minutes. Maximum standardized uptake values (SUV{sub max}) of regions of interest were measured at 60, 90, and 120 minutes. The SUV{sub max} slope between 60 and 120 minutes and change of SUV{sub max} slope before and after 90 minutes were calculated. Data were analyzed by primary site and nodal site disease status using the Cox regression model and Wilcoxon rank sum test. Outcomes were based on pathologic and clinical follow-up. Results: A total of 84 patients were enrolled, with 79 primary and 43 nodal evaluable sites. Twenty-eight sites were interpreted as positive or equivocal (18 primary, 8 nodal, 2 distant) on 3-month 90-minute FDG-PET/CT. Median follow-up was 13.3 months. All measured SUV endpoints predicted recurrence. Change of SUV{sub max} slope after 90 minutes more accurately identified nonrecurrence in positive or equivocal sites than our current standard of SUV{sub max} ≥2.5 (P=.02). Conclusions: The positive predictive value of post-RT FDG-PET/CT may significantly improve using novel second derivative analysis of dynamic triphasic FDG-PET/CT SUV{sub max} slope, accurately distinguishing tumor from inflammation on positive and equivocal scans.

21 CFR 868.1730 - Oxygen uptake computer.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Oxygen uptake computer. 868.1730 Section 868.1730...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1730 Oxygen uptake computer. (a) Identification. An oxygen uptake computer is a device intended to compute the amount of oxygen consumed by a...

18F-FDG uptake in breast cancer correlates with immunohistochemically defined subtypes

International Nuclear Information System (INIS)

Koo, Hye Ryoung; Park, Jeong Seon; Kang, Keon Wook; Cho, Nariya; Chang, Jung Min; Bae, Min Sun; Kim, Won Hwa; Lee, Su Hyun; Seo, Mirinae; Moon, Woo Kyung; Kim, Mi Young; Kim, Jin You

2014-01-01

To determine whether a correlation exists between maximum standardized uptake value (SUV max ) on 18 F-fluorodeoxyglucose positron emission tomography (FDG-PET) and the subtypes of breast cancer. This retrospective study involved 548 patients (mean age 51.6 years, range 21-81 years) with 552 index breast cancers (mean size 2.57 cm, range 1.0-14.5 cm). The correlation between 18 F-FDG uptake in PET/CT, expressed as SUV max , and immunohistochemically defined subtypes (luminal A, luminal B, human epidermal growth factor receptor 2 (HER2) positive and triple negative) was analyzed. The mean SUV max value of the 552 tumours was 6.07 ± 4.63 (range 0.9-32.8). The subtypes of the 552 tumours were 334 (60 %) luminal A, 66 (12 %) luminal B, 60 (11 %) HER2 positive and 92 (17 %) triple negative, for which the mean SUV max values were 4.69 ± 3.45, 6.51 ± 4.18, 7.44 ± 4.73 and 9.83 ± 6.03, respectively. In a multivariate regression analysis, triple-negative and HER2-positive tumours had 1.67-fold (P max values, respectively, than luminal A tumours after adjustment for invasive tumour size, lymph node involvement status and histologic grade. FDG uptake was independently associated with subtypes of invasive breast cancer. Triple-negative and HER2-positive breast cancers showed higher SUV max values than luminal A tumours. circle 18 F-FDG PET demonstrates increased tissue glucose metabolism, a hallmark of cancers. (orig.)

Effect of perfluorooctane sulfonate on toxicity and cell uptake of other compounds with different hydrophobicity in green alga.

Science.gov (United States)

Liu, Wei; Zhang, Yao-Bin; Quan, Xie; Jin, Yi-He; Chen, Shuo

2009-04-01

Perfluorooctane sulfonate (PFOS) was evaluated alone and in binary mixtures with pentachlorophenol, atrazine and diuron, respectively to investigate the effects of interactions between PFOS and other compounds on the growth rate in Scenedesmus obliquus. Single application of PFOS showed no inhibition on the growth of S. obliquus below 40 mg L(-1), whereas PFOS acting with pentachlorophenol resulted in higher algal growth inhibition in comparison with pentachlorophenol alone. A maximum increase of 45% in the growth inhibition was observed at a pentachlorophenol concentration of 2.56 mg L(-1) together with a PFOS concentration of 40 mg L(-1). On the contrary, the algal growth inhibition of atrazine and diuron was depressed by PFOS. Furthermore, cell uptake was examined to gain some insights into the mechanisms of the effects of PFOS on the toxicity of the other compounds. Cell uptake of pentachlorophenol increased while that of atrazine and diuron was reduced in cells that have been exposed to PFOS. The effects of PFOS on the toxicity of pentachlorophenol, atrazine and diuron were possibly related to the influence of PFOS on the cell uptake of these hydrophobic compounds. Results suggested that PFOS influenced the cell uptake and toxicity of structurally different compounds in dissimilar manners and potentially increased the accessibility and toxicity of more hydrophobic compounds to algal cells.

Incidental focal FDG uptake in the parotid glands on PET/CT in patients with head and neck malignancy

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Seo, Young Lan; Yoon, Dae Young; Lim, Kyoung Ja; Yun, Eun Joo; Cho, Young Kwon [Hallym University College of Medicine, Department of Radiology, Kangdong Seong-Sim Hospital, Seoul (Korea, Republic of); Baek, Sora [Hallym University College of Medicine, Department of Nuclear Medicine, Kangdong Seong-Sim Hospital, Seoul (Korea, Republic of); Bae, Woo Jin; Chung, Eun Jae; Kwon, Kee Hwan [Hallym University College of Medicine, Department of Otorhinolaryngology, Ilsong Memorial Institute of Head and Neck Cancer, Kangdong Seong-Sim Hospital, Seoul (Korea, Republic of)

2015-01-15

To evaluate the prevalence and clinical significance of focal parotid lesions identified by {sup 18} F- FDG PET/CT in patients with nonparotid head and neck malignancies. From 3,638 PET/CT examinations using {sup 18} F-FDG conducted on 1,342 patients with nonparotid head and neck malignancies, we retrospectively identified patients showing incidental focal FDG uptake in the parotid glands. The diagnosis of parotid lesions was confirmed histopathologically or on imaging follow-up. Patient demographics, clinical features, maximum standardized uptake value (SUV{sub max}) on PET images, size and attenuation on corresponding contrast-enhanced CT images were assessed and correlated with the final diagnosis. The prevalence of incidental focal parotid FDG uptake on PET/CT was 2.1 % (95 % CI 1.4 - 3.0 %). Among 21 patients with focal parotid lesions confirmed histologically or on imaging follow-up, 7 (33.3 %) had malignant lesions (all metastases) and 14 (66.7 %) had benign lesions (four pleomorphic adenomas, two Warthin's tumours, one benign lymph node, one granulomatous lesion, six lesions without histopathological confirmation). There were no significant differences in age, sex, SUV{sub max} or CT findings between patients with benign and those with malignant lesions. Focal parotid FDG uptake on PET/CT in patients with head and neck malignancy warrants further investigations to ensure adequate therapy for incidental parotid lesions. (orig.)

Correlation between 5-Minute {sup 99m}Tc-Pertechnetate Uptake and 24-Hour {sup 131}I Uptake in Patients with Thyroid Disease

Energy Technology Data Exchange (ETDEWEB)

Lee, Chan Woo; Won, Kyu Chang; Yoon, Hyun Dae; Cho, In Ho; Kim, Tae Nyeun; Shin, Dong Gu; Lee, Hyoung Woo; Shim, Bong Sup; Lee, Hyun Woo [Yeungnam University School of Medicine, Daegu (Korea, Republic of)

1992-07-15

The 20-minute {sup 99m}Tc-pertechnetate uptake became readily available for routine use and it replaced {sup 131}I for thyroid imaging. However measuring thyroid uptake during a 5-minute minimizes pertechnetate uptake by the salivary glands and presence of contaminated saliva from those glands in to the pharynx and esophagus. A study was carried out to determine the suitability of the utility of a 5-minute and 20-minute interval from administration of {sup 99m}Tc-pertechnetate to imaging and uptake measurement as a replacement for the 24 hour standard originally established with {sup 131}I, and to evaluate the relationship between 5-minute {sup 99m}Tc-pertechnetate uptake and other thyroid functions. A 5-minute and 20-minute uptake of {sup 99m}Tc-pertechnetate were measured in 70 patients with thyroid disease at Yeungnam University Hospital from March 1, 1991 to Feb. 29, 1992. The results were as follows. 1) The 5-minute {sup 99m}Tc-pertechnetate uptake in Graves' disease, Hashimoto's thyroiditis, simple goiter non toxic nodular goiter, subacute thyroiditis and euthyroid were 18.2%, 14.6%, 2.8%, 3.2%, 1.2% and 1.1%, respectively. There was a significant difference between the mean of the euthyroid group and the mean of the Graves' disease. So differentiation between them can be easily made. 2) The 5 minute {sup 99m}Tc- pertechnetate thyroid uptake was well correlated with 24 hour {sup 131}I thyroid uptake (r=0.75, p<0.001). These data provided an equation for estimating the 24 hour uptake of iodide given the 5 minute pertechnetate uptake: Estimated 24-hour '1{sup 31}I thyroid Uptake = 7.188{sup *}In (5 minute {sup 99m}Tc-Pertechnetate uptake)+16.94 3) The 20-minute {sup 99m}Tc-pertechnetate thyroid uptake was well correlated with 24-hour {sup 131}I uptake (r=0.72, p<0.001) and 5-minute {sup 99m}Tc-pertechnetate thyroid uptake (r=0.96, p<0.001). 4) In the Graves' disease, The 5-minute {sup 99m}Tc-pertechnetate thyroid uptake was well

Kinetics of phosphate uptake, growth, and accumulation of cyclic diphosphoglycerate in a phosphate-limited continuous culture of Methanobacterium thermoautotrophicum.

Science.gov (United States)

Krueger, R D; Harper, S H; Campbell, J W; Fahrney, D E

1986-07-01

The archaebacterium Methanobacterium thermoautotrophicum was grown in continuous culture at 65 degrees C in a phosphate-limited medium at specific growth rates from 0.06 to 0.28 h-1 (maximum growth rate [mu max] = 0.36 h-1). Cyclic-2,3-diphosphoglycerate (cyclic DPG) levels ranged from 2 to 20 mM in Pi-limited cells, compared with about 30 mM in batch-grown cells. The Monod constant for Pi-limited growth was 5 nM. Pi uptake rates were determined by following the disappearance of 32Pi from the medium. Interrupting the H2 supply stopped the uptake of Pi and the release of organic phosphates. Little or no efflux of Pi occurred in the presence or absence of H2. Pi uptake of cells adapted to nanomolar Pi concentrations could be accounted for by the operation of one uptake system with an apparent Km of about 25 nM and a Vmax of 58 nmol of Pi per min per g (dry weight). Uptake curves at 30 microM Pi or above were biphasic due to a sevenfold decrease in Vmax after an initial phase of rapid movement of Pi into the cell. Under these conditions the growth rate slowed to zero and the cyclic DPG pool expanded before growth resumed. Thus, three properties of M. thermoautotrophicum make it well adapted to live in a low-P environment: the presence of a low-Km, high-Vmax uptake system for Pi; the ability to accumulate cyclic DPG rapidly; and a growth strategy in which accumulation of Pi and cyclic DPG takes precedence over a shift-up in growth rate when excess Pi becomes available.

Kinetics of phosphate uptake, growth, and accumulation of cyclic diphosphoglycerate in a phosphate-limited continuous culture of Methanobacterium thermoautotrophicum.

Science.gov (United States)

Krueger, R D; Harper, S H; Campbell, J W; Fahrney, D E

1986-01-01

The archaebacterium Methanobacterium thermoautotrophicum was grown in continuous culture at 65 degrees C in a phosphate-limited medium at specific growth rates from 0.06 to 0.28 h-1 (maximum growth rate [mu max] = 0.36 h-1). Cyclic-2,3-diphosphoglycerate (cyclic DPG) levels ranged from 2 to 20 mM in Pi-limited cells, compared with about 30 mM in batch-grown cells. The Monod constant for Pi-limited growth was 5 nM. Pi uptake rates were determined by following the disappearance of 32Pi from the medium. Interrupting the H2 supply stopped the uptake of Pi and the release of organic phosphates. Little or no efflux of Pi occurred in the presence or absence of H2. Pi uptake of cells adapted to nanomolar Pi concentrations could be accounted for by the operation of one uptake system with an apparent Km of about 25 nM and a Vmax of 58 nmol of Pi per min per g (dry weight). Uptake curves at 30 microM Pi or above were biphasic due to a sevenfold decrease in Vmax after an initial phase of rapid movement of Pi into the cell. Under these conditions the growth rate slowed to zero and the cyclic DPG pool expanded before growth resumed. Thus, three properties of M. thermoautotrophicum make it well adapted to live in a low-P environment: the presence of a low-Km, high-Vmax uptake system for Pi; the ability to accumulate cyclic DPG rapidly; and a growth strategy in which accumulation of Pi and cyclic DPG takes precedence over a shift-up in growth rate when excess Pi becomes available. PMID:3722128

Uranium uptake of Vetiveria zizanioides (L.) Nash

International Nuclear Information System (INIS)

Luu Viet Hung; Maslov, O.D.; Trinh Thi Thu My; Phung Khac Nam Ho; Dang Duc Nhan

2010-01-01

Uranium uptake of vetiver grass (Vetiveria zizanioides (L.) Nash) from Eutric Fluvisols (AK), Albic Acrisols (BG), Dystric Fluvisols (HP) and Ferralic Acrisols (TC) in northern Vietnam is assessed. The soils were mixed with aqueous solution of uranyl nitrate to make soils contaminated with uranium at 0, 50, 100, 250 mg/kg before planting the grass. The efficiency of uranium uptake by the grass was assessed based on the soil-to-plant transfer factor (TF U , kg·kg -1 ). It was found that the TF U values are dependent upon the soils properties. CEC facilitates the uptake and the increased soil pH could reduce the uptake and translocation of uranium in the plant. Organic matter content, as well as iron and potassium, inhibits the uranium uptake of the grass. It was revealed that the lower fertile soil, the higher uranium uptake. The translocation of uranium in root for all the soil types studied is almost higher than that in its shoot. It seems that vetiver grass could potentially be used for the purpose of phytoremediation of soils contaminated with uranium

Monocyte transferrin-iron uptake in hereditary hemochromatosis

International Nuclear Information System (INIS)

Sizemore, D.J.; Bassett, M.L.

1984-01-01

Transferrin-iron uptake by peripheral blood monocytes was studied in vitro to test the hypothesis that the relative paucity of mononuclear phagocyte iron loading in hereditary hemochromatosis results from a defect in uptake of iron from transferrin. Monocytes from nine control subjects and 17 patients with hemochromatosis were cultured in the presence of 59Fe-labelled human transferrin. There was no difference in 59Fe uptake between monocytes from control subjects and monocytes from patients with hemochromatosis who had been treated by phlebotomy and who had normal body iron stores. However, 59Fe uptake by monocytes from iron-loaded patients with hemochromatosis was significantly reduced compared with either control subjects or treated hemochromatosis patients. It is likely that this was a secondary effect of iron loading since iron uptake by monocytes from treated hemochromatosis patients was normal. Assuming that monocytes in culture reflect mononuclear phagocyte iron metabolism in vivo, this study suggests that the relative paucity of mononuclear phagocyte iron loading in hemochromatosis is not related to an abnormality in transferrin-iron uptake by these cells

Correlation of high {sup 18}F-FDG uptake to clinical, pathological and biological prognostic factors in breast cancer

Energy Technology Data Exchange (ETDEWEB)

Groheux, David; Moretti, Jean-Luc; Hindie, Elif [Department of Nuclear Medicine, Saint-Louis Hospital,Assistance publique Hopitaux de Paris, Paris Cedex 10 (France); IUH, Doctoral School, University of Paris VII, Paris (France); Giacchetti, Sylvie; Espie, Marc; Hamy, Anne-Sophie; Cuvier, Caroline [Breast Diseases Unit, Saint-Louis Hospital, Department of Medical Oncology, Paris (France); Porcher, Raphael [Saint-Louis Hospital, Department of Biostatistics and Medical Information, Paris (France); Lehmann-Che, Jacqueline [Saint-Louis Hospital, Department of Biochemistry, Paris (France); Roquancourt, Anne de [Saint-Louis Hospital, Department of Pathology, Paris (France); Vercellino, Laetitia [Department of Nuclear Medicine, Saint-Louis Hospital, Assistance publique Hopitaux de Paris, Paris Cedex 10 (France)

2011-03-15

The aim of this study was to determine the impact of the main clinicopathological and biological prognostic factors of breast cancer on {sup 18}F-fluorodeoxyglucose (FDG) uptake. Only women with tumours larger than 20 mm (T2-T4) were included in order to minimize bias of partial volume effect. In this prospective study, 132 consecutive women received FDG PET/CT imaging before starting neoadjuvant chemotherapy. Maximum standardized uptake values (SUV{sub max}) were compared to tumour characteristics as assessed on core biopsy. There was no influence of T and N stage on SUV. Invasive ductal carcinoma showed higher SUV than lobular carcinoma. However, the highest uptake was found for metaplastic tumours, representing 5% of patients in this series. Several biological features usually considered as bad prognostic factors were associated with an increase in FDG uptake: the median of SUV{sub max} was 9.7 for grade 3 tumours vs 4.8 for the lower grades (p < 0.0001); negativity for oestrogen receptors (ER) was associated with higher SUV (ER+ SUV = 5.5; ER- SUV = 7.6; p = 0.003); triple-negative tumours (oestrogen and progesterone receptor negative, no overexpression of c-erbB-2) had an SUV of 9.2 vs 5.8 for all others (p = 0005); p53 mutated tumours also had significantly higher SUV (7.8 vs 5.0; p < 0.0001). Overexpression of c-erbB-2 had no effect on the SUV value. Knowledge of the factors influencing uptake is important when interpreting FDG PET/CT scans. Also, findings that FDG uptake is highest in those patients with poor prognostic features (high grade, hormone receptor negativity, triple negativity, metaplastic tumours) is helpful to determine who are the best candidates for baseline staging. (orig.)

Hg uptake in ureteral obstructions

International Nuclear Information System (INIS)

Desgrez, J.P.; Bourguignon, M.; Raynaud, C.; CEA, 91 - Orsay

1976-01-01

In the presence of a total obstruction the results obtained with the Hg uptake test, as indeed with other functional tests, inform on the value of the kidney function at the time but have no prognostic value where repair possibilities are concerned. Some preliminary results seem to show however that very soon after the obstacle is removed, by the 10th or 15th day perhaps, quantitative functional tests may once more be used to evaluate the functional prognosis. This would mean that by waiting about two weeks after the disappearance of a total obstruction the Hg uptake test may again be used in all confidence. In order to check this deduction, which is based on slender evidence but which nevertheless has important practical implications, the measurement of the Hg uptake rate during the days following removal of the obstacle appears essential. In long-standing partial obstructions the Hg uptake rate gives an accurate assessment of the functional balance and helps considerably in the choice of therapy [fr

Measuring the serotonin uptake site using [3H]paroxetine--a new serotonin uptake inhibitor

International Nuclear Information System (INIS)

Gleiter, C.H.; Nutt, D.J.

1988-01-01

Serotonin is an important neurotransmitter that may be involved in ethanol preference and dependence. It is possible to label the serotonin uptake site in brain using the tricyclic antidepressant imipramine, but this also binds to other sites. We have used the new high-affinity uptake blocker paroxetine to define binding to this site and report it to have advantages over imipramine as a ligand

Immuno-PET of undifferentiated thyroid carcinoma with radioiodine-labelled antibody cMAb U36: application to antibody tumour uptake studies

Energy Technology Data Exchange (ETDEWEB)

Fortin, Marc-Andre [Centre Hospitalier Universitaire de Quebec and Laval University, Laboratory for Biomaterials and Bioengineering, Quebec City (Canada); Uppsala University, Biomedical Radiation Sciences, Department of Oncology, Radiology, and Clinical Immunology, Rudbeck Laboratory, Uppsala (Sweden); Salnikov, Alexei V. [Uppsala University, BMC, Department of Medical Biochemistry and Microbiology, Uppsala (Sweden); German Cancer Research Center, Division of Molecular Immunology, Heidelberg (Germany); Nestor, Marika [Uppsala University, Division of Otolaryngology and Head and Neck Surgery, Department of Surgical Sciences, Uppsala (Sweden); Heldin, Nils-Erik [Uppsala University, Department of Genetics and Pathology, Rudbeck Laboratory, Uppsala (Sweden); Rubin, Kristofer [Uppsala University, BMC, Department of Medical Biochemistry and Microbiology, Uppsala (Sweden); Lundqvist, Hans [Uppsala University, Biomedical Radiation Sciences, Department of Oncology, Radiology, and Clinical Immunology, Rudbeck Laboratory, Uppsala (Sweden)

2007-09-15

We tested the suitability of the chimeric monoclonal anti-human CD44 splice version 6 antibody (cMAb U36) for targeting and visualising human anaplastic thyroid carcinoma with PET. We also performed experiments aimed at elucidating the relation between tumour interstitial fluid pressure (TIFP) and the tumour uptake of antibodies. The affinity and specificity of the cMAb U36 for KAT-4 cells were evaluated in vitro, as was the Na{sup +}/I{sup -} symporter (NIS) expression. Biodistribution studies were performed on KAT-4 carcinoma-bearing mice injected with {sup 124}I-cMAb U36 or free iodine. Biodistribution studies were also performed in animals treated with the specific TGF-{beta}1 and -{beta}3 inhibitor Fc:T{beta}RII, which lowers TIFP. Treated and non-treated animals were scanned by microPET. Cultured human undifferentiated/anaplastic thyroid carcinoma KAT-4 cells expressed low levels of NIS and uptake of free iodine was insignificant. The cMAb U36 expressed an affinity (K{sub D}) of 11 {+-} 2 nM. Tumour radioactivity uptake reached maximum values 48 h after injection of {sup 124}I-cMAb U36 ({proportional_to}22%IA/g). KAT-4 carcinomas were readily identified in all {sup 124}I-immuno-PET images. Radioactivity tumour uptake in Fc:T{beta}RII-treated animals was significantly lower at 24 and 48 h after injection, and five times higher thyroid uptake was also noted. We successfully used {sup 124}I-cMAb U36 to visualise CD44v6-expressing human anaplastic thyroid carcinoma. Given the lack of NIS expression in KAT-4, tumour visualisation is not due to free iodine uptake. Lowering the TIFP in KAT-4 carcinomas did not increase the uptake of mAbs into tumour tissue. (orig.)

FDG uptake and glut-1 expression in primary tumors and loco-regional lymph nodes in non-small-cell lung cancer

International Nuclear Information System (INIS)

Lee, Won Woo; Nguyen, Xuan Canh; Chung, Jin Haeng; Park, So Yeon; Kim, Sang Eun

2007-01-01

FDG uptake level by primary tumors in NSCLC may affect the likelihood of malignant involvement in loco-regional lymph nodes (LNs). FDG uptake in tumors has been reported to be mediated by glucose transporter type 1 (Glut-I). Here, we investigated the correlations between primary tumors and loco-regional LNs in NSCLC regarding FDG uptake and Glut-1 expression. 126 NSCLC patients (M: F=103: 23, age=659.7y) who underwent curative resection and loco-regional LN dissection within 4 week period after FDG-PET study were enrolled. Maximum standardized uptake value (maxSUV) by PET and %Glut-1 expression by immunostaining were compared between primary tumors and FDG uptake positive loco-regional LNs. Significant correlations were found between 52 malignant LNs and 37 primary tumors in terms of maxSUV (r=0.6451, p<0.0001) and %Glut-1 expression (r=0.8341, p<0.0001). Linear regression of the relation between maxSUVs of malignant LNs (Y) and maxSUVs of primary tumors (X) yielded the expression Y = 0.5938 + 0.4808 X with an r2 value of 0.4162. On the other hand, no significant correlation was observed between 144 benign LNs and 75 primary tumors in terms of maxSUVs (r= -0.0125, p 0.8831). Moreover, %Glut-1 expressions of pathologically proven benign LNs and primary tumors were found to be correlated (r=0.3863, p=0.0004), but r2 value was low at 0.1492. High correlations were found between primary tumors and loco-regional metastatic LNs in NSCLC regarding FDG uptake and Glut-1 expression. Mediastinal LN staging of NSCLC by FDG-PET may be improved by considering the linear correlation between FDG uptakes of metastatic LNs and primary tumors

Ocean carbon uptake and storage

International Nuclear Information System (INIS)

Tilbrook, Bronte

2007-01-01

Full text: The ocean contains about 95% of the carbon in the atmosphere, ocean and land biosphere system, and is of fundamental importance in regulating atmospheric carbon dioxide concentrations. In the 1990s an international research effort involving Australia was established to determine the uptake and storage of anthropogenic C02 for all major ocean basins. The research showed that about 118 of the 244 + 20 billion tons of the anthropogenic carbon emitted through fossil fuel burning and cement production has been stored in the ocean since preindustrial times, thus helping reduce the rate of increase in atmospheric C02. The research also showed the terrestrial biosphere has been a small net source of C02 (39 ± 28 billion tons carbon) to the atmosphere over the same period. About 60% of the total ocean inventory of the anthropogenic C02 was found in the Southern Hemisphere, with most in the 30 0 S to 50 0 S latitude band. This mid-latitude band is where surface waters are subducted as Mode and Intermediate waters, which is a major pathway controlling ocean C02 uptake. High storage (23% of the total) also occurs in the North Atlantic, associated with deep water formation in that basin. The ocean uptake and storage is expected to increase in the coming decades as atmospheric C02 concentrations rise. However, a number of feedback mechanisms associated with surface warming, changes in circulation, and biological effects are likely to impact on the uptake capacity. The accumulation or storage-of the C02 in the ocean is also the major driver of ocean acidification with potential to disrupt marine ecosystems. This talk will describe the current understanding of the ocean C02 uptake and storage and a new international research strategy to detect how the ocean uptake and storage will evolve on interannual through decadal scales. Understanding the ocean response to increasing atmospheric C02 will be a key element in managing future C02 increases and establishing

Correlation of primary tumor FDG uptake with clinicopathologic prognostic factors in invasive ductal carcinoma of the breast

International Nuclear Information System (INIS)

Jo, I; Kim, Sung Hoon; Kim, Hae Won; Kang, Sung Hee; Zeon, Seok Kil; Kim, Su Jin

2015-01-01

The purpose of this study was to investigate the correlation of primary tumor FDG uptake to clinicopathological prognostic factors in invasive ductal carcinoma of the breast. We retrospectively reviewed 136 of 215 female patients with pathologically proven invasive ductal breast cancer from January 2008 to December 2011 who underwent F-18 FDG PET/CT for initial staging and follow-up after curative treatment with analysis of estrogen receptor (ER), progesterone receptor (PR) and human epithelial growth factor receptor 2 (HER2). The maximum standardized uptake value (SUV max ) of the primary breast tumor was measured and compared with hormonal receptor and HER2 overexpression status. The high SUV max of primary breast tumors is significantly correlated with the clinicopathological factors: tumor size, histologic grade, TNM stage, negativity of ER, negativity of PR, HER2 overexpression and triple negativity. The recurrent group with non-triple negative cancer had a higher SUV max compared with the non-recurrent group, though no significant difference in FDG uptake was noted between the recurrence and non-recurrent groups in subjects with triple-negative cancer. Lymph node involvement was the independent risk factor for cancer recurrence in the multivariate analysis. In conclusion, high FDG uptake in primary breast tumors is significantly correlated with clinicopathological factors, such as tumor size, histologic grade, TNM stage, negativity of the hormonal receptor, HER2 overexpression and triple negativity. Therefore, FDG PET/CT is a helpful prognostic tool to direct the further management of patients with breast cancer

Impact of blood glucose, diabetes, insulin, and obesity on standardized uptake values in tumors and healthy organs on 18F-FDG PET/CT

International Nuclear Information System (INIS)

Büsing, Karen A.; Schönberg, Stefan O.; Brade, Joachim; Wasser, Klaus

2013-01-01

Introduction: Chronically altered glucose metabolism interferes with 18 F-FDG uptake in malignant tissue and healthy organs and may therefore lower tumor detection in 18 F-FDG PET/CT. The present study assesses the impact of elevated blood glucose levels (BGL), diabetes, insulin treatment, and obesity on 18 F-FDG uptake in tumors and biodistribution in normal organ tissues. Methods: 18 F-FDG PET/CT was analyzed in 90 patients with BGL ranging from 50 to 372 mg/dl. Of those, 29 patients were diabetic and 21 patients had received insulin prior to PET/CT; 28 patients were obese with a body mass index > 25. The maximum standardized uptake value (SUV max ) of normal organs and the main tumor site was measured. Differences in SUV max in patients with and without elevated BGLs, diabetes, insulin treatment, and obesity were compared and analyzed for statistical significance. Results: Increased BGLs were associated with decreased cerebral FDG uptake and increased uptake in skeletal muscle. Diabetes and insulin diminished this effect, whereas obesity slightly enhanced the outcome. Diabetes and insulin also increased the average SUV max in muscle cells and fat, whereas the mean cerebral SUV max was reduced. Obesity decreased tracer uptake in several healthy organs by up to 30%. Tumoral uptake was not significantly influenced by BGL, diabetes, insulin, or obesity. Conclusions: Changes in BGLs, diabetes, insulin, and obesity affect the FDG biodistribution in muscular tissue and the brain. Although tumoral uptake is not significantly impaired, these findings may influence the tumor detection rate and are therefore essential for diagnosis and follow-up of malignant diseases

Self-microemulsifying drug delivery system for improving the bioavailability of huperzine A by lymphatic uptake

Directory of Open Access Journals (Sweden)

Fang Li

2017-05-01

Full Text Available Huperzine A (Hup-A is a poorly water-soluble drug with low oral bioavailability. A self-microemulsifying drug delivery system (SMEDDS was used to enhance the oral bioavailability and lymphatic uptake and transport of Hup-A. A single-pass intestinal perfusion (SPIP technique and a chylomicron flow-blocking approach were used to study its intestinal absorption, mesenteric lymph node distribution and intestinal lymphatic uptake. The value of the area under the plasma concentration–time curve (AUC of Hup-A SMEDDS was significantly higher than that of a Hup-A suspension (P<0.01. The absorption rate constant (Ka and the apparent permeability coefficient (Papp for Hup-A in different parts of the intestine suggested a passive transport mechanism, and the values of Ka and Papp of Hup-A SMEDDS in the ileum were much higher than those in other intestinal segments. The determination of Hup-A concentration in mesenteric lymph nodes can be used to explain the intestinal lymphatic absorption of Hup-A SMEDDS. For Hup-A SMEDDS, the values of AUC and maximum plasma concentration (Cmax of the blocking model were significantly lower than those of the control model (P<0.05. The proportion of lymphatic transport of Hup-A SMEDDS and Hup-A suspension were about 40% and 5%, respectively, suggesting that SMEDDS can significantly improve the intestinal lymphatic uptake and transport of Hup-A.

P-32 uptake in lentic algae

International Nuclear Information System (INIS)

Strange, J.R.; Williamson, G.D.; Fletcher, D.J.

1975-01-01

A study of the Flat Creek Embayment of Lake Sidney Lanier near Gainesville, Georgia revealed three genera of algae, Chlorococcum, Fragillaria and Nostoc, to be prominent in this eutrophic region of the lake. The algae was grown in phosphate-rich media and subsequently labelled with P-32. All species incorporated luxury amounts of phosphorus as determined by the uptake of P-32. The results indicate that the P-32 uptake is proportional to the surface-per-volume ratio. The higher surface-per-volume ratio resulted in greater uptake of P-32

Plutonium uptake by marine phytoplankton in culture

International Nuclear Information System (INIS)

Fisher, N.S.; Olson, B.L.; Bowen, V.T.

1980-01-01

At environmentally realistic atom concentrations 237 Pu tracer was used to examine Pu uptake by unialgla cultures of Thalassiosira pseudonana (live and dead), Thalassiosira sp., and Platymonas sp., as well as by glass particles. Live or dead cells and glass particles accumulated Pu at similar rates, indicating that initial uptake was a passive phenomenon. Uptake was strongly affected by the nature of particle surfaces, but much less by composition of the media. Cells from rapidly growing cultures took up more Pu, than did those from late log or senescent cultures. Acid-washed glass took up more Pu, faster, than did unwashed glass. Cells accumulated more Pu from uv-treated seawater than from seawater untreated or enriched with f/50-level EDTA or f/50 vitamins; from complete f/50 medium uptake was even less, as with f/50 trace metals + EDTA. After a shot uptake Pu was 25% removable in tracer-free media, but after 3 days of uptake none was removable in seawater or exometabolite media, and only 15% in f/50-level EDTA. The data support the hypothesis that Pu in marine environments associates with suspended particles that could act as vertical vectors for this element

Impacts of biological and procedural factors on semiquantification uptake value of liver in fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography imaging.

Science.gov (United States)

Mahmud, Mohd Hafizi; Nordin, Abdul Jalil; Ahmad Saad, Fathinul Fikri; Azman, Ahmad Zaid Fattah

2015-10-01

Increased metabolic activity of fluorodeoxyglucose (FDG) in tissue is not only resulting of pathological uptake, but due to physiological uptake as well. This study aimed to determine the impacts of biological and procedural factors on FDG uptake of liver in whole body positron emission tomography/computed tomography (PET/CT) imaging. Whole body fluorine-18 ((18)F) FDG PET/CT scans of 51 oncology patients have been reviewed. Maximum standardized uptake value (SUVmax) of lesion-free liver was quantified in each patient. Pearson correlation was performed to determine the association between the factors of age, body mass index (BMI), blood glucose level, FDG dose and incubation period and liver SUVmax. Multivariate regression analysis was established to determine the significant factors that best predicted the liver SUVmax. Then the subjects were dichotomised into four BMI groups. Analysis of variance (ANOVA) was established for mean difference of SUVmax of liver between those BMI groups. BMI and incubation period were significantly associated with liver SUVmax. These factors were accounted for 29.6% of the liver SUVmax variance. Statistically significant differences were observed in the mean SUVmax of liver among those BMI groups (Pvalue for physiological liver SUVmax as a reference standard for different BMI of patients in PET/CT interpretation and use a standard protocol for incubation period of patient to reduce variation in physiological FDG uptake of liver in PET/CT study.

Focal uptake of 68Ga-DOTATOC in the pancreas: pathological or physiological correlate in patients with neuroendocrine tumours?

International Nuclear Information System (INIS)

Al-Ibraheem, Akram; Bundschuh, Ralph Alexander; Notni, Johannes; Winter, Anna; Wester, Hans-Juergen; Schwaiger, Markus; Scheidhauer, Klemens; Buck, Andreas

2011-01-01

Neuroendocrine tumours are frequently located in the upper abdomen and especially in the pancreas. Imaging of the abdomen with somatostatin analogs such as 68 Ga-DOTA-Phe 1 -Tyr 3 -octreotide (DOTATOC) is a standard approach for imaging neuroendocrine cancer, but is still challenging due to physiological and technical considerations in this area. Therefore, the aim of this study was to further investigate the origin of 68 Ga-DOTATOC findings in the pancreas. Forty-three consecutive patients with neuroendocrine tumours were examined by 68 Ga-DOTATOC positron emission tomography (PET)/CT for staging or restaging. As imaging of the upper abdomen is frequently affected by breathing artefacts, PET and CT data were analysed for misalignment and rearranged if necessary. Any noticeable uptake in the pancreas was described. Tracer uptake in the head of the pancreas and the liver was measured by means of maximum and average standard uptake value (SUV max , SUV av ). The reference standards (malignant versus benign) for correlation with PET findings were clinical and radiological follow-up (mean follow-up time 14 months) (n = 37) or histological confirmation (n = 6). In 23 of 43 studies (54%) misalignment between PET and CT data was found with a mean value of 1.4 cm. Visual assessment demonstrated that 20 of 43 scans (46.6%) showed no uptake in the head of the pancreas. Of 43 scans, 23 (53.4%) showed noticeable uptake with focal pattern in the head of the pancreas in 10 scans and irregular pattern in 13 scans. Follow-up indicated malignant pancreatic lesions in three patients. The pancreatic head to liver SUV av ratios in these patients ranged from 1.62 to 6.85, whereas in cases of uptake without known malignancy ratios ranged from 0.56 to 1.19. Considering SUV max , the ratio ranged from 3.24 to 9.1 and from 0.84 to 1.47, respectively. No statistically significant difference was noted between uptake in the head of the pancreas and the liver in patients without malignant

Nutrient Uptake by High-Yielding Cotton Crop in Brazil

Directory of Open Access Journals (Sweden)

José Luís Vilela Vieira

2018-02-01

Full Text Available ABSTRACT: Determining nutrient uptake and accumulation rates by cotton crops is important to define management strategies, especially for transgenic varieties, which are cultivated using high-technology approaches that require substantial investment to maximize yield. Currently in Brazil, the states of Bahia and Mato Grosso are responsible for 84.4 % of the total cotton growing area. In the present study, two trials were conducted in 2013, one that involved planting FM 940 GLT, FM 980 GLT, and FM 913 GLT varieties in the state of Bahia and the other which involved FM 940 GLT and FM 980 GLT varieties in the state of Mato Grosso. The aim of the two trials was to represent the two regions that currently encompass the largest areas of cotton cultivation. Tissue samples, consisting of leaves, stems, and reproductive components, were collected eleven times during the crop cycle for determination of nutrient content and shoot dry matter. After weighing, plant tissue samples were dried and ground to determine nutrient contents. Because there were no overall differences in nutrient contents and biomass accumulation of the varieties during the crop cycle, we undertook joint analysis of the data from all varieties at each site. Favorable climatic conditions in Bahia promoted plant biomass production that was twice as much as plants grown in Mato Grosso, with cotton yields of 6.2 and 3.8 t ha−1 of lint and seed, respectively. The maximum nutrient accumulation occurred between 137-150 days after emergence (DAE for N; 143-148 for P; 172-185 for K; 100 for Ca; 144-149 for Mg; and 153-158 for S. Maximum uptake ranged from 218-362 kg ha−1 N; 26-53 kg ha−1 P; 233-506 kg ha−1 K; 91-202 kg ha−1 Ca; 28-44 kg ha−1 Mg; and 19-61 kg ha−1 S. On average, the sites revealed nutrient export of 14, 2, 23, 3, 2, and 2 kg t−1 of lint and seed for N, P, K, Ca, Mg, and S, respectively, with little variation among sites. Extraction of nutrients per area by cotton

Circadian rhythm in ''1''5O-labeled water uptake manner of a soybean plant by PETIS (Positron Emitting Tracer Imaging System)

Energy Technology Data Exchange (ETDEWEB)

Nakanishi, Tomoko M.; Yokota, Harumi; Tanoi, Keitaro; Furukawa, Jun; Ikeue, Natsuko; Ookuni, Yoko [Tokyo Univ. (Japan). Graduate School of Agricultural and Life Sciences; Uchida, Hiroshi; Tsuji, Atsunori

2001-05-01

We present a circadian rhythm of water uptake manner in a soybean plant through realtime imaging of water, labeled with {sup 15}O. Nitrogen gas was irradiated with deuterons accelerated by a cyclotron at Hamamatsu Photonics Co. to produce {sup 15}O-labeled water. Then the {sup 15}O-labeled water was supplied to a soybean plant from the root and the realtime water uptake amount was measured for 20 min by Positron Emitting Tracer Imaging System (PETIS). All the targeting positions for the measurements were stems, two points at an internode between root and the first leaves, between the first leaves and the first trifoliates and between the first trifoliates and the second trifoliates. The water uptake amount was gradually increased and showed its maximum at around 13:00, especially at the basal part of the stem. Then the water uptake activity was gradually decreased until 17:00. The water amount taken up by a plant at 13:00 was about 40% higher than that at 17:00. (author)

Factors influencing physiological FDG uptake in the intestine

International Nuclear Information System (INIS)

Yasuda, Seiei; Takahashi, Wakoh; Takagi, Shigeharu; Fujii, Hirofumi; Ide, Michiru; Shohtsu, Akira

1998-01-01

The intestine is a well-known site of physiological 18 F-fluorodeoxyglucose (FDG) accumulation in positron emission tomography (PET). To identify factors influencing physiological FDG uptake in the intestine, the intensity of FDG uptake was evaluated in a total of 1,068 healthy adults. Non-attenuation-corrected whole-body PET images were obtained for all subjects and visually evaluated. Subjects were then classified into two groups according to the intensity of intestinal FDG uptake. Sex, age, presence or absence of constipation, and serum glucose, hemoglobin A 1 c, and free fatty acid levels were compared between the two groups. High intestinal FDG uptake was observed at an overall rate of 11.0%. Sex (female), age, and bowel condition (constipation) were found to affect intestinal FDG uptake. The factors we identified lead to further questions the relationship between intestinal motility and glucose uptake that warrant further study. (author)

Electron uptake by iron-oxidizing phototrophic bacteria

Energy Technology Data Exchange (ETDEWEB)

Bose, A; Gardel, EJ; Vidoudez, C; Parra, EA; Girguis, PR

2014-02-26

Oxidation-reduction reactions underlie energy generation in nearly all life forms. Although most organisms use soluble oxidants and reductants, some microbes can access solid-phase materials as electron-acceptors or -donors via extracellular electron transfer. Many studies have focused on the reduction of solid-phase oxidants. Far less is known about electron uptake via microbial extracellular electron transfer, and almost nothing is known about the associated mechanisms. Here we show that the iron-oxidizing photoautotroph Rhodopseudomonas palustris TIE-1 accepts electrons from a poised electrode, with carbon dioxide as the sole carbon source/electron acceptor. Both electron uptake and ruBisCo form I expression are stimulated by light. Electron uptake also occurs in the dark, uncoupled from photosynthesis. Notably, the pioABC operon, which encodes a protein system essential for photoautotrophic growth by ferrous iron oxidation, influences electron uptake. These data reveal a previously unknown metabolic versatility of photoferrotrophs to use extracellular electron transfer for electron uptake.

CONSEXPO 3.0, consumer exposure and uptake models

NARCIS (Netherlands)

Veen MP van; LBM

2001-01-01

The report provides a modelling approach to consumer exposure to chemicals, based on mathematical contact, exposure and uptake models. For each route of exposure, a number of exposure and uptake models are included. A general framework joins the exposure and uptake models selected by the user. By

Cosmic shear measurement with maximum likelihood and maximum a posteriori inference

Science.gov (United States)

Hall, Alex; Taylor, Andy

2017-06-01

We investigate the problem of noise bias in maximum likelihood and maximum a posteriori estimators for cosmic shear. We derive the leading and next-to-leading order biases and compute them in the context of galaxy ellipticity measurements, extending previous work on maximum likelihood inference for weak lensing. We show that a large part of the bias on these point estimators can be removed using information already contained in the likelihood when a galaxy model is specified, without the need for external calibration. We test these bias-corrected estimators on simulated galaxy images similar to those expected from planned space-based weak lensing surveys, with promising results. We find that the introduction of an intrinsic shape prior can help with mitigation of noise bias, such that the maximum a posteriori estimate can be made less biased than the maximum likelihood estimate. Second-order terms offer a check on the convergence of the estimators, but are largely subdominant. We show how biases propagate to shear estimates, demonstrating in our simple set-up that shear biases can be reduced by orders of magnitude and potentially to within the requirements of planned space-based surveys at mild signal-to-noise ratio. We find that second-order terms can exhibit significant cancellations at low signal-to-noise ratio when Gaussian noise is assumed, which has implications for inferring the performance of shear-measurement algorithms from simplified simulations. We discuss the viability of our point estimators as tools for lensing inference, arguing that they allow for the robust measurement of ellipticity and shear.

Quantifying [{sup 18}F]fluorodeoxyglucose uptake in the arterial wall: the effects of dual time-point imaging and partial volume effect correction

Energy Technology Data Exchange (ETDEWEB)

Blomberg, Bjoern A. [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Odense University Hospital, Department of Nuclear Medicine, Odense (Denmark); Bashyam, Arjun; Ramachandran, Abhinay; Gholami, Saeid; Houshmand, Sina; Salavati, Ali; Werner, Tom; Alavi, Abass [Hospital of the University of Pennsylvania, Department of Radiology, Philadelphia, PA (United States); Zaidi, Habib [Geneva University Hospital, Division of Nuclear Medicine and Molecular Imaging, Geneva (Switzerland); University of Groningen, Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, Groningen (Netherlands)

2015-08-15

The human arterial wall is smaller than the spatial resolution of current positron emission tomographs. Therefore, partial volume effects should be considered when quantifying arterial wall {sup 18}F-FDG uptake. We evaluated the impact of a novel method for partial volume effect (PVE) correction with contrast-enhanced CT (CECT) assistance on quantification of arterial wall {sup 18}F-FDG uptake at different imaging time-points. Ten subjects were assessed by CECT imaging and dual time-point PET/CT imaging at approximately 60 and 180 min after {sup 18}F-FDG administration. For both time-points, uptake of {sup 18}F-FDG was determined in the aortic wall by calculating the blood pool-corrected maximum standardized uptake value (cSUV{sub MAX}) and cSUV{sub MEAN}. The PVE-corrected SUV{sub MEAN} (pvcSUV{sub MEAN}) was also calculated using {sup 18}F-FDG PET/CT and CECT images. Finally, corresponding target-to-background ratios (TBR) were calculated. At 60 min, pvcSUV{sub MEAN} was on average 3.1 times greater than cSUV{sub MAX} (P <.0001) and 8.5 times greater than cSUV{sub MEAN} (P <.0001). At 180 min, pvcSUV{sub MEAN} was on average 2.6 times greater than cSUV{sub MAX} (P <.0001) and 6.6 times greater than cSUV{sub MEAN} (P <.0001). This study demonstrated that CECT-assisted PVE correction significantly influences quantification of arterial wall {sup 18}F-FDG uptake. Therefore, partial volume effects should be considered when quantifying arterial wall {sup 18}F-FDG uptake with PET. (orig.)

Evaluation of a cumulative SUV-volume histogram method for parameterizing heterogeneous intratumoural FDG uptake in non-small cell lung cancer PET studies

International Nuclear Information System (INIS)

Velden, Floris H.P. van; Cheebsumon, Patsuree; Yaqub, Maqsood; Hoekstra, Otto S.; Lammertsma, Adriaan A.; Boellaard, Ronald; Smit, Egbert F.

2011-01-01

Standardized uptake values (SUV) are commonly used for quantification of whole-body [ 18 F]fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) studies. Changes in SUV following therapy, however, only provide a proper measure of response in case of homogeneous FDG uptake in the tumour. The purpose of this study was therefore to implement and characterize a method that enables quantification of heterogeneity in tumour FDG uptake. Cumulative SUV-volume histograms (CSH), describing % of total tumour volume above % threshold of maximum SUV (SUV max ), were calculated. The area under a CSH curve (AUC) is a quantitative index of tumour uptake heterogeneity, with lower AUC corresponding to higher degrees of heterogeneity. Simulations of homogeneous and heterogeneous responses were performed to assess the value of AUC-CSH for measuring uptake and/or response heterogeneity. In addition, partial volume correction and image denoising was applied prior to calculating AUC-CSH. Finally, the method was applied to a number of human FDG scans. Partial volume correction and noise reduction improved CSH curves. Both simulations and clinical examples showed that AUC-CSH values corresponded with level of tumour heterogeneity and/or heterogeneity in response. In contrast, this correspondence was not seen with SUV max alone. The results indicate that the main advantage of AUC-CSH above other measures, such as 1/COV (coefficient of variation), is the possibility to measure or normalize AUC-CSH in different ways. AUC-CSH might be used as a quantitative index of heterogeneity in tracer uptake. In response monitoring studies it can be used to address heterogeneity in response. (orig.)

Efficacy of a new tan doped sol-gel sorbent for uptake of zinc

International Nuclear Information System (INIS)

Khan, A.; Ahmed, S.; Riaz, M.; Mahmood, F.; Younas Khokhar, M.

2003-01-01

A TAN (1-(2-Thiazolylazo)-2-naphthol) doped sol gel silica sorbent (reddish colour, porous, stable, hard, non-swelling) were prepared and investigated for the removal of Zn (II) from aqueous solutions. The kinetics, adsorption isotherm, equilibration time and pH effect on the removal were studied from non competitive aqueous solution to optimize the conditions to be utilized on a large scale. Fast equilibration was observed and adsorption equilibria were reached within 30 minutes. Adsorption of zinc ions on the blank (un-doped) sol gel was found negligible. The maximum adsorption of Zn (II) ions onto the TAN doped sol-gel from single solutions were 2.33 mg/g (0.035 mmol/g). TAN doped sol gel can be regenerated through washing with a solution of 0.1 M HCl solution. The maximum regeneration value was as high as 99.0%. The TAN-doped sol gel silica is suitable at least for four adsorption-desorption cycles without experiencing considerable loss of adsorption capacity. The uptake route and the nature of the Zn-TAN complex have been discussed. (orig.)

Dependence of FDG uptake on tumor microenvironment

International Nuclear Information System (INIS)

Pugachev, Andrei; Ruan, Shutian; Carlin, Sean; Larson, Steven M.; Campa, Jose; Ling, C. Clifton; Humm, John L.

2005-01-01

Purpose: To investigate the factors affecting the 18 F-fluorodeoxyglucose ( 18 F-FDG) uptake in tumors at a microscopic level, by correlating it with tumor hypoxia, cellular proliferation, and blood perfusion. Methods and Materials: Nude mice bearing Dunning prostate tumors (R3327-AT) were injected with 18 F-FDG and pimonidazole, bromodeoxyuridine, and, 1 min before sacrifice, with Hoechst 33342. Selected tumor sections were imaged by phosphor plate autoradiography, while adjacent sections were used to obtain the images of the spatial distribution of Hoechst 33342, pimonidazole, and bromodeoxyuridine. The images were co-registered and analyzed on a pixel-by-pixel basis. Results: Statistical analysis of the data obtained from these tumors demonstrated that 18 F-FDG uptake was positively correlated with pimonidazole staining intensity in each data set studied. Correlation of FDG uptake with bromodeoxyuridine staining intensity was always negative. In addition, FDG uptake was always negatively correlated with the staining intensity of Hoechst 33342. Conclusions: For the Dunning prostate tumors studied, FDG uptake was always positively correlated with hypoxia and negatively correlated with both cellular proliferation and blood flow. Therefore, for the tumor model studied, higher FDG uptake is indicative of tumor hypoxia, but neither blood flow nor cellular proliferation

**-Postprandial pancreatic ["1"1C]methionine uptake after pancreaticoduodenectomy mirrors basal beta cell function and insulin release

International Nuclear Information System (INIS)

Steiner, Emanuel; Kazianka, Lukas; Breuer, Robert; Miholic, Johannes; Hacker, Marcus; Wadsak, Wolfgang; Mitterhauser, Markus; Stimpfl, Thomas; Reiter, Birgit; Karanikas, Georgios

2017-01-01

[S-methyl-"1"1C]-L-methionine (["1"1C]MET) uptake in the pancreas might be a central indicator of beta cell function. Since gastric emptying was recently shown to influence glycemic control in subjects after pancreaticoduodenectomy (PD, the surgical treatment of neoplasms of the pancreas head), we looked for imaginable relationships between gastric emptying, pre- and postprandial insulin concentrations, and ["1"1C]MET uptake. Nineteen tumor-free survivors after PD (age mean ± SD: 61 ± 8.7 yrs.; 10 male, 9 female) and 10 healthy controls (age: 27 ± 8.7 yrs.; 7 male, 3 female) were given a mixed test meal. One gram of paracetamol was ingested with the meal to evaluate the speed of gastric emptying. Insulin, glucose, and paracetamol plasma concentrations were measured before and over 180 minutes after ingestion. Beta cell function was calculated from fasting glucose and insulin plasma concentrations. Simultaneously, 800 MBq of ["1"1C]MET were administered and the activity (maximum tissue standardized uptake values [SUVmax]) over the pancreas was measured at 15, 30, and 60 minutes after injection. Total integrated SUVmax (area under the curve [AUC]) and incremental SUVmax were calculated. The uptake of ["1"1C]MET in the pancreas was significantly higher (p < 0.0001) in controls compared to the PD group. Gastric emptying was significantly slower in controls compared to pancreatectomy subjects (p < 0.0001). Paracetamol AUC_3_0 correlated with the SUVmax increment between 15 and 30 minutes (R"2 = 0.27, p = 0.0263), suggesting a relationship between gastric emptying and the uptake of ["1"1C]MET. Total integrated SUVmax correlated with insulin AUC_6_0 (R"2 = 0.66,p < 0.0001) in patients after PD. Multivariate regression analysis revealed insulin AUC_6_0 and beta cell function, calculated from the fasting insulin to glucose ratio, as independent predictors of "1"1C-methionine uptake, i.e. total integrated SUVmax, in patients after PD (R"2 = 0.78, p < 0.0001). Postprandial

Patterns of FDG uptake in stomach on F-18 FDG positron emission tomography: correlation with endoscopic findings

Energy Technology Data Exchange (ETDEWEB)

Chae, Min Jeong; Cheon, Gi Jeong; Lee, Sang Woo; Byun, Byung Hyun; Kim, Sung Eun; Kim, Yu Chul; Choi, Chang Woon; Lim, Sang Moo [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

2005-10-15

We often find variable degrees of FDG uptake and patterns in stomach, which can make difficult to distinguish physiologic uptake from pathologic uptake on FDG PET. The purpose of this study was to find out the significant findings of stomach on FDG PET. Thirty-eight patients who underwent both FDG PET and endoscopy within one week from Jun. 2003, to Aug. 2004 were included in this study. We reviewed 38 patients (18 for medical check up, 15 for work up of other malignancies, and 5 for the evaluation of stomach lesion). Their mean age was 56 years old (range:32 {approx} 79), men and women were 28 and 10, respectively. Two nuclear physicians evaluated five parameters on FDG PET findings of stomach with a consensus: 1) visual grades 2) maximum SUV (max.SUV) 3) focal 4) diffuse and 5) asymmetric patterns. We correlated the lesions of FDG PET findings of stomach with those of endoscopy. We considered more than equivocal findings on FDG PET as positive. The six of 38 patients were proven as malignant lesions by endoscopic biopsy and others were inflammatory lesions (ulcer in 3, chronic atrophic gastritis in 12, uncommon forms of gastritis in 5), non-inflammatory lesions (n=3), and normal stomach (n=9). By the visual analysis, malignant lesions had higher FDG uptake than the others. The max.SUV of malignant lesions was 7.95 {+-} 4.83 which was significantly higher than the other benign lesions (2.9 {+-} 0.69 in ulcer, 3.08 {+-} 1.2 in chronic atrophic gastritis, 3.2 {+-} 1.49 in uncommon forms of gastritis ( {rho} =0.044). In the appearance of stomach on FDG PET, malignant lesions were shown focal (5 of 6) and benign inflammatory lesions were shown diffuse (9 of 20) and asymmetric (14 of 20). Benign lesions and normal stomach were shown variable degrees of uptake and patterns. Some cases of benign inflammatory lesions such as ulcer and gastritis were shown focal and mimicked cancerous lesions (4 of 15). Gastric malignant lesions had higher FDG uptake and focal pattern

Patterns of FDG uptake in stomach on F-18 FDG positron emission tomography: correlation with endoscopic findings

International Nuclear Information System (INIS)

Chae, Min Jeong; Cheon, Gi Jeong; Lee, Sang Woo; Byun, Byung Hyun; Kim, Sung Eun; Kim, Yu Chul; Choi, Chang Woon; Lim, Sang Moo

2005-01-01

We often find variable degrees of FDG uptake and patterns in stomach, which can make difficult to distinguish physiologic uptake from pathologic uptake on FDG PET. The purpose of this study was to find out the significant findings of stomach on FDG PET. Thirty-eight patients who underwent both FDG PET and endoscopy within one week from Jun. 2003, to Aug. 2004 were included in this study. We reviewed 38 patients (18 for medical check up, 15 for work up of other malignancies, and 5 for the evaluation of stomach lesion). Their mean age was 56 years old (range:32 ∼ 79), men and women were 28 and 10, respectively. Two nuclear physicians evaluated five parameters on FDG PET findings of stomach with a consensus: 1) visual grades 2) maximum SUV (max.SUV) 3) focal 4) diffuse and 5) asymmetric patterns. We correlated the lesions of FDG PET findings of stomach with those of endoscopy. We considered more than equivocal findings on FDG PET as positive. The six of 38 patients were proven as malignant lesions by endoscopic biopsy and others were inflammatory lesions (ulcer in 3, chronic atrophic gastritis in 12, uncommon forms of gastritis in 5), non-inflammatory lesions (n=3), and normal stomach (n=9). By the visual analysis, malignant lesions had higher FDG uptake than the others. The max.SUV of malignant lesions was 7.95 ± 4.83 which was significantly higher than the other benign lesions (2.9 ± 0.69 in ulcer, 3.08 ± 1.2 in chronic atrophic gastritis, 3.2 ± 1.49 in uncommon forms of gastritis ( ρ =0.044). In the appearance of stomach on FDG PET, malignant lesions were shown focal (5 of 6) and benign inflammatory lesions were shown diffuse (9 of 20) and asymmetric (14 of 20). Benign lesions and normal stomach were shown variable degrees of uptake and patterns. Some cases of benign inflammatory lesions such as ulcer and gastritis were shown focal and mimicked cancerous lesions (4 of 15). Gastric malignant lesions had higher FDG uptake and focal pattern. However, benign

**-Postprandial pancreatic [{sup 11}C]methionine uptake after pancreaticoduodenectomy mirrors basal beta cell function and insulin release

Energy Technology Data Exchange (ETDEWEB)

Steiner, Emanuel; Kazianka, Lukas; Breuer, Robert; Miholic, Johannes [Medical University of Vienna, Department of Surgery, Vienna (Austria); Hacker, Marcus; Wadsak, Wolfgang; Mitterhauser, Markus [Medical University of Vienna, Department of Biomedical Imaging and Image-Guided Therapy, Division of Nuclear Medicine, Vienna (Austria); Stimpfl, Thomas; Reiter, Birgit [Medical University of Vienna, Clinical Institute of Laboratory Medicine, Forensic Toxicology, Vienna (Austria); Karanikas, Georgios [Medical University of Vienna, Department of Biomedical Imaging and Image-Guided Therapy, Division of Nuclear Medicine, Divisional Head PET-PET/CT (Nuclear Medicine), Vienna (Austria)

2017-03-15

[S-methyl-{sup 11}C]-L-methionine ([{sup 11}C]MET) uptake in the pancreas might be a central indicator of beta cell function. Since gastric emptying was recently shown to influence glycemic control in subjects after pancreaticoduodenectomy (PD, the surgical treatment of neoplasms of the pancreas head), we looked for imaginable relationships between gastric emptying, pre- and postprandial insulin concentrations, and [{sup 11}C]MET uptake. Nineteen tumor-free survivors after PD (age mean ± SD: 61 ± 8.7 yrs.; 10 male, 9 female) and 10 healthy controls (age: 27 ± 8.7 yrs.; 7 male, 3 female) were given a mixed test meal. One gram of paracetamol was ingested with the meal to evaluate the speed of gastric emptying. Insulin, glucose, and paracetamol plasma concentrations were measured before and over 180 minutes after ingestion. Beta cell function was calculated from fasting glucose and insulin plasma concentrations. Simultaneously, 800 MBq of [{sup 11}C]MET were administered and the activity (maximum tissue standardized uptake values [SUVmax]) over the pancreas was measured at 15, 30, and 60 minutes after injection. Total integrated SUVmax (area under the curve [AUC]) and incremental SUVmax were calculated. The uptake of [{sup 11}C]MET in the pancreas was significantly higher (p < 0.0001) in controls compared to the PD group. Gastric emptying was significantly slower in controls compared to pancreatectomy subjects (p < 0.0001). Paracetamol AUC{sub 30} correlated with the SUVmax increment between 15 and 30 minutes (R{sup 2} = 0.27, p = 0.0263), suggesting a relationship between gastric emptying and the uptake of [{sup 11}C]MET. Total integrated SUVmax correlated with insulin AUC{sub 60} (R{sup 2} = 0.66,p < 0.0001) in patients after PD. Multivariate regression analysis revealed insulin AUC{sub 60} and beta cell function, calculated from the fasting insulin to glucose ratio, as independent predictors of {sup 11}C-methionine uptake, i.e. total integrated SUVmax, in

Exertional oxygen uptake kinetics: a stamen of stamina?

Science.gov (United States)

Whipp, Brian J; Rossiter, H B; Ward, S A

2002-04-01

The fundamental pulmonary O(2) uptake (.VO(2)) response to moderate, constant-load exercise can be characterized as (d.VO(2)/dt)(tau)+Delta.VO(2) (t)=Delta.VO(2SS) where Delta.VO(2SS) is the steady-state response, and tau is the time constant, with the .VO(2) kinetics reflecting intramuscular O(2) uptake (.QO(2)) kinetics, to within 10%. The role of phosphocreatine (PCr) turnover in .QO(2) control can be explored using (31)P-MR spectroscopy, simultaneously with .VO(2). Although tau.VO(2) and tauPCr vary widely among subjects (approx. 20-65 s), they are not significantly different from each other, either at the on- or off-transient. A caveat to interpreting the "well-fit" exponential is that numerous units of similar Delta.VO(2SS) but with a wide tau distribution can also yield a .VO(2) response with an apparent single tau. This tau is, significantly, inversely correlated with lactate threshold and .VO(2max)(but is poorly predictive; a frail stamen, therefore), consistent with tau not characterizing a compartment with uniform kinetics. At higher intensities, the fundamental kinetics become supplemented with a slowly-developing phase, setting .VO(2)on a trajectory towards maximum .VO(2). This slow component is also demonstrable in Delta[PCr]: the decreased efficiency thereby reflecting a predominantly high phosphate-cost of force production rather than a high O(2)-cost of phosphate production. We also propose that the O(2)-deficit for the slow-component is more likely to reflect shifting Delta.VO(2SS) rather than a single one with a single tau.

Comparison between FDG Uptake and Clinicopathologic and Immunohistochemical Parameters in Pre-operative PET/CT Scan of Primary Gastric Carcinoma

International Nuclear Information System (INIS)

Han, Eun Ji; Choi, Woo Hee; Chung, Yong An; Kim, Ki Jun; Maeng, Lee So; Sohn, Kyung Myung; Jung, Hyun Suk; Sohn, Hyung Sun; Chung, Soo Kyo

2009-01-01

The purpose of this study was to find out what clinicopathologic or immunohistochemical parameter that may affect FDG uptake of primary tumor in PET/CT scan of the gastric carcinoma patient. Eighty-nine patients with stomach cancer who underwent pre-operative FDG PET/CT scans were included. In cases with perceptible FDG uptake in primary tumor, the maximum standardized uptake value (SUVmax) was calculated. The clinicopathologic results such as depth of invasion (T stage), tumor size, lymph node metastasis, tumor differentiation and Lauren's classification and immunohistochemical markers such as Ki-67 index, expression of p53, EGFR, Cathepsin D, c-erb-B2 and COX-2 were reviewed. Nineteen out of 89 gastric carcinomas showed imperceptible FDG uptake on PET/CT images. In cases with perceptible FDG uptake in primary tumor, SUVmax was significantly higher in T2, T3 and T4 tumors than T1 tumors (5.8±3.1 vs. 3.7±2.1, p=0.002). SUVmax of large tumors (above or equal to 3 cm) was also significantly higher than SUVmax of small ones (less than 3 cm) (5.7±3.2 vs. 3.7±2.0, p=0.002). The intestinal types of gastric carcinomas according to Lauren showed higher FDG uptake compared to the non-intestinal types (5.4±2.8 vs. 3.7±1.3, p=0.003). SUVmax between p53 positive group and negative group was significantly different (6.0±2.8 vs. 4.4±3.0, p=0.035). No significant difference was found in presence of LN metastasis, tumor differentiation, Ki-67 index, and expression of EGFR, Cathepsin D, c-erb-B2 and COX-2. T stage of gastric carcinoma influenced the detectability of gastric cancer on FDG PET/CT scan. When gastric carcinoma was perceptible on PET/CT scan, T stage, size of primary tumor, Lauren's classification and p53 expression were related to degree of FDG uptake in primary tumor

Mechanisms of DNA uptake by cells

Energy Technology Data Exchange (ETDEWEB)

Lacks, S.A.

1977-01-01

Three categories of cellular uptake of DNA can be distinguished. First, in the highly transformable bacteria, such as Diplococcus pneumoniae, Haemophilus influenzae and Bacillus subtilis, elaborate mechanisms of DNA transport have evolved, presumably for the purpose of genetic exchange. These mechanisms can introduce substantial amounts of DNA into the cell. Second, methods have been devised for the forced introduction of DNA by manipulation of bacterial cells under nonphysiological conditions. By such means small but significant amounts of DNA have been introduced into various bacteria, including Escherichia coli. Third, mammalian cells are able to take up biologically active DNA. This has been most clearly demonstrated with viral DNA, although the mechanism of uptake is not well understood. The intention, here, is to survey current understanding of the various mechanisms of DNA uptake. A review of experience with the bacterial systems may throw some light on the mammalian system and lead to suggestions for enhancing DNA uptake by mammalian cells.

Short-term uptake of heavy metals by periphyton algae

Energy Technology Data Exchange (ETDEWEB)

Vymazal, J.

1984-12-31

The utilization of periphyton for the removal of heavy metals from enriched small streams has been examined. By means of short-term batch laboratory experiments the courses of metal uptake have been studied. For uptake study naturally growing periphyton community and periphytic filamentous algae Cladophora glomerata and Oedogonium rivulare have been used. Uptakes of nine heavy metals (Pb, Cd, Cu, Co, Cr, Ni, Zn, Fe and Mn) have been determined during four hours exposure. In addition the influence of humic substances on heavy metals uptake has been determined. Uptake of all metals increased during four hours exposure but not in the same way. Some metals were removed continuously (Ni, Cr, Fe and Mn), other metals were removed more rapidly during the first hour or first two hours of exposure and then only slight removal continued (Cu, Pb, Cd, Co). Uptake of Zn was rather unambiguous. Results of these experiments suggest that the course of uptake for individual metals could be similar for most periphyton algae. It was established that humic substances significantly reduce heavy metals uptake. The highest decrease of uptake was observed in Cu, Cr, Co and Cd. The results of model experiments are being tested in a pilot scale with respect to the demands of engineering practice. (J.R.)

Phosphorus deficiency enhances molybdenum uptake by tomato plants

International Nuclear Information System (INIS)

Heuwinkel, H.; Kirkby, E.A.; Le Bot, J.; Marschner, H.

1992-01-01

Water culture experiments are described which provide conclusive evidence that Mo uptake by tomato plants is markedly enhanced by P deficiency. In a longterm experiment, which ran for 11 days, in marked contrast to the uptake of other nutrients, a three fold higher Mo uptake rate was observed after only four days of withdrawal of P from the nutrient medium. In contrast to the gradual increase in pH of the nutrient medium of the plants supplied with P, the pH in the medium of the -P plants fell. Throughout the growth of these plants net H+ efflux could be accounted for by excess cation over anion uptake, indicating that organic acid extrusion plays no major role in the observed fall in pH. Further evidence that Mo uptake is enhanced in P deficient tomato plants is provided in short-term nutrient solution experiments (1h and 4h) using radioactive molybdenum (99Mo). Compared with P sufficient plants, the uptake rates of 99Mo by P deficient plants were three to five times higher after 1h and nine to twelve times higher after 4h. Resupplying P during the uptake periods to deficient plants reduced the uptake rate of 99Mo to values similar to those of P sufficient plants. It is concluded that the uptake of molybdate occurs via phosphate binding/ transporting sites at the plasma membrane of root cells. Further support for this conclusion comes from exchange experiments with non-labelled molybdenum, which show a much larger amount of 99Mo exchangeable from the roots of P deficient plants

Skeletal muscle glucose uptake during dynamic exercise in humans

DEFF Research Database (Denmark)

Richter, Erik; Kiens, Bente; Saltin, Bengt

1988-01-01

uptake was not compensated for by increased uptake of free fatty acids but was accompanied by decreases in plasma insulin and increases in plasma epinephrine and norepinephrine. During work with large muscle masses, arterial lactate increased to approximately 6 mM, and net leg lactate release reverted......To study the role of muscle mass in glucoregulation, six subjects worked with the knee extensors of one leg on a specially constructed cycle ergometer. The knee extensors of one leg worked either alone or in combination with the knee extensors of the other leg and/or with the arms. Substrate usage...... to net lactate uptake. Decreased glucose uptake could not be explained by decreased perfusion. It is concluded that thigh muscle glucose uptake is affected by the size of the total muscle mass engaged in exercise. The decrease in thigh glucose uptake, when arm cranking was added and O2 uptake...

Evaluation of hilar 67Ga-citrate uptake in bronchogenic carcinoma

International Nuclear Information System (INIS)

Matsuno, Noriyo; Kuyama, Junpei; Uchida, Yoshitaka; Hatano, Osamu; Imai, Yasunori; Uno, Kimiichi; Minoshima, Satoshi.

1995-01-01

We evaluated hilar uptake on 67 Ga-citrate scintigraphy and correlated with hilar lymph node metastases in one-hundred seventeen cases (two-hundred thirty four hila) of bronchogenic carcinoma. Hilar uptake was classified into three grades independently on anterior and posterior chest views: no uptake (grade 0), uptake equal to that in the thoracic vertebrae (grade 1), and uptake higher than that in the thoracic vertebrae (grade 2). If a summed grade of anterior and posterior view was larger than 3, hilar uptake was considered as positive. In forty-four cases (forty-nine hila) with hilar lymph node metastases, positive hilar uptake was found in ten cases (eleven hila), resulting in sensitivity of 22% based on cases and 23% based on hila. In seventy-three cases (one-hundred forty-six hila) without hilar lymph node metastases, positive hilar uptake was found in six cases (ten hila), resulting in specificity of 91% based on cases and 93% based on hila. In comparison to scintigraphic findings of unilaterally positive hilar uptake, findings of bilaterally positive hilar uptake showed significantly lower accuracy in determining presence of hilar lymph node metastases. No definite correlation between hilar uptake and histopathology or 67 Ga-citrate uptake in a primary tumor was observed. The results indicate that usefulness of 67 Ga-citrate scintigraphy is limited when evaluating hilar lymph node metastases in bronchogenic carcinoma. (author)

Capturing Individual Uptake: Toward a Disruptive Research Methodology

Science.gov (United States)

Bastian, Heather

2015-01-01

This article presents and illustrates a qualitative research methodology for studies of uptake. It does so by articulating a theoretical framework for qualitative investigations of uptake and detailing a research study designed to invoke and capture students' uptakes in a first-year writing classroom. The research design sought to make uptake…

Uptake and transport of positron-emitting tracer (18F) in plants

International Nuclear Information System (INIS)

Kume, Tamikazu; Matsuhashi, Shinpei; Shimazu, Masamitsu

1997-01-01

The transport of a positron-emitting isotope introduced into a plant was dynamically followed by a special observation apparatus called Positron-Emitting Tracer Imaging System' to observe the damage and recovery functions of plants in vivo. In the system, annihilation γ-rays from the positron emitter are detected with two planar detectors (5 x 6 cm 2 ). The water containing ca. 5 MBq/ml of 18 F was fed to the cut stem of soybean for 2 min and then the images of tracer activity were recorded for 30-50 min. When the midrib of a leaf near the petiole was cut just before measurement, the activity in the injured leaf was decreased but detected even at the apex. This result suggests that the damaged leaf recovered the uptake of water through the lamina. Maximum tracer activities in leaves of unirradiated plant were observed within 10 min, whereas those of irradiated plant at 100 Gy were observed after over 25 min. The final activity of irradiated plant after 30 min was lower than that of unirradiated plant. In case of beans, there was a difference in the absorption behavior of the 18 F-labeled water between unirradiated and irradiated samples. These results show that the system is effective to observe the uptake and transportation of water containing positron emitting tracer for the study of damage and recovery functions of plants. (Author)

IDH mutation is paradoxically associated with higher {sup 18}F-FDOPA PET uptake in diffuse grade II and grade III gliomas

Energy Technology Data Exchange (ETDEWEB)

Verger, A. [APHM, La Timone Hospital, Department of Nuclear Medicine, Marseille (France); Lorraine University, Department of Nuclear Medicine and Nancyclotep Imaging Platform, CHRU Nancy, Nancy (France); Lorraine University, IADI, INSERM, UMR 947, Nancy (France); Metellus, P. [Centre Hospitalier Prive Clairval, Department of Neurosurgery, Marseille (France); Aix-Marseille University, INSERM, UMR 911, Marseille (France); Sala, Q. [APHM, La Timone Hospital, Department of Nuclear Medicine, Marseille (France); Colin, C. [Aix-Marseille University, INSERM, UMR 911, Marseille (France); Bialecki, E. [Centre Hospitalier Prive Clairval, Department of Neurosurgery, Marseille (France); Taieb, D. [APHM, La Timone Hospital, Department of Nuclear Medicine, Marseille (France); Aix-Marseille University, CERIMED, Marseille (France); Chinot, O. [Aix-Marseille University, INSERM, UMR 911, Marseille (France); APHM, La Timone Hospital, Department of Neuro-Oncology, Marseille (France); Figarella-Branger, D. [Aix-Marseille University, INSERM, UMR 911, Marseille (France); APHM, La Timone Hospital, Department of Anatomopathology, Marseille (France); Guedj, E. [APHM, La Timone Hospital, Department of Nuclear Medicine, Marseille (France); Aix-Marseille University, CERIMED, Marseille (France); Aix-Marseille University, Institut de Neurosciences de la Timone, CNRS, UMR 7289, Marseille (France); Hopital de la Timone, Service Central de Biophysique et Medecine Nucleaire, Marseille (France)

2017-08-15

The World Health Organization Classification of Tumors of the Central Nervous System has recently been updated by the integration of diagnostic and prognostic molecular parameters, giving pivotal attention to IDH mutation as a favourable factor. Amino acid PET is increasingly used in the management of gliomas, but its prognostic value is a matter of debate. The aim of this study was to assess the relationship between IDH mutation and {sup 18}F-FDOPA uptake on PET in newly diagnosed gliomas. A total of 43 patients, presenting with diffuse astrocytic and oligodendroglial grade II and III gliomas, reclassified according to the 2016 WHO classification of tumours of the CNS, were retrospectively included. They had all undergone {sup 18}F-FDOPA PET at an initial stage before surgery and histological diagnosis. {sup 18}F-FDOPA uptake values were compared between patients with and without IDH mutation in terms of maximum standardized uptake value (SUVmax) ratios between tumour and normal contralateral brain (T/N), and between tumour and striatum (T/S). Patients with IDH mutation showed higher {sup 18}F-FDOPA T/N SUVmax ratios (1.6 vs. 1.2) and T/S SUVmax ratios (0.9 vs. 0.6) than patients without IDH mutation (p < 0.05). This study showed paradoxically higher {sup 18}F-FDOPA uptake in diffuse grade II and III gliomas with IDH mutation. Despite evident interest in the management of gliomas, and especially in relation to posttherapy evaluation, our findings raise the question of the prognostic value of {sup 18}F-FDOPA uptake on PET uptake in this group of patients. This may be related to differences in amino acid integration, metabolism, or cell differentiation. (orig.)

Uptake mechanism for iodine species to black carbon.

Science.gov (United States)

Choung, Sungwook; Um, Wooyong; Kim, Minkyung; Kim, Min-Gyu

2013-09-17

Natural organic matter (NOM) plays an important role in determining the fate and transport of iodine species such as iodide (I(-)) and iodate (IO3(-)) in groundwater system. Although NOM exists as diverse forms in environments, prior iodine studies have mainly focused on uptake processes of iodide and iodate to humic materials. This study was conducted to determine the iodide and iodate uptake potential for a particulate NOM (i.e., black carbon [BC]). A laboratory-produced BC and commercial humic acid were used for batch experiments to compare their iodine uptake properties. The BC exhibited >100 times greater uptake capability for iodide than iodate at low pH of ~3, while iodide uptake was negligible for the humic acid. The uptake properties of both solids strongly depend on the initial iodine aqueous concentrations. After uptake reaction of iodide to the BC, X-ray absorption fine structure spectroscopy results indicated that the iodide was converted to electrophilic species, and iodine was covalently bound to carbon atom in polycyclic aromatic hydrocarbons present in the BC. The computed distribution coefficients (i.e., Kd values) suggest that the BC materials retard significantly the transport of iodide at low pH in environmental systems containing even a small amount of BC.

Increased Phosphorus Uptake by Wheat and Field Beans Inoculated with a Phosphorus-Solubilizing Penicillium bilaji Strain and with Vesicular-Arbuscular Mycorrhizal Fungi.

Science.gov (United States)

Kucey, R M

1987-12-01

Greenhouse and field experiments were conducted to test the effect of a P-solubilizing isolate of Penicillium bilaji on the availability of Idaho rock phosphate (RP) in a calcareous soil. Under controlled greenhouse conditions, inoculation of soils with P. bilaji along with RP at 45 mug of P per g of soil resulted in plant dry matter production and P uptake by wheat (Triticum aestivum) and beans (Phaseolus vulgaris) that were not significantly different from the increases in dry matter production and P uptake caused by the addition of 15 mug of P per g of soil as triple superphosphate. Addition of RP alone had no effect on plant growth. Addition of vesicular-arbuscular mycorrhizal fungi was necessary for maximum effect in the sterilized soil in the greenhouse experiment. Under field conditions, a treatment consisting of RP (20 kg of P per ha of soil) plus P. bilaji plus straw resulted in wheat yields and P uptake equivalent to increases due to the addition of monoammonium phosphate added at an equivalent rate of P. RP added alone had no effect on wheat growth or P uptake. The results indicate that a biological system of RP solubilization can be used to increase the availability of RP added to calcareous soils.

Uptake of SPECT radiopharmaceuticals in neocortical brain cultures

Energy Technology Data Exchange (ETDEWEB)

Jong, B.M. de; Royen, E.A. van

1989-01-01

The uptake, retention and uptake antagonism of /sup 201/Tl-DDC, /sup 201/Tl-Cl, /sup 123/I-IMP, /sup 99m/Tc-HMPAO and /sup 99m/Tc-O4/sup -/ were compared in rat neocortex cultures. /sup 201/Tl-DDC and /sup 123/I-IP revealed the highest uptake of radioactivity in the cultures. /sup 99m/Tc-HMPAO and /sup 123/I-IMP showed the highest retention of radioactivity within the tissue in washout experiments. Blocking of bioelectric activity by tetrodotoxin did not significantly affect the uptake of the radiopharmaceuticals (RPHA). Inhibition of Na K ATPase by ouabain inhibited the uptake of /sup 201/Tl-Cl (77%) and /sup 201/Tl-DDC (27%). Imipramine showed a significantly stronger inhibitory effect on /sup 123/I-IMP uptake in comparison with the effect on other RPHA. /sup 99m/Tc-O4/sup -/ was not concentrated within the cultured tissue. Under the in vitro conditions used in this study, the various RPHA were characterised by distinct differences in their interaction with cortical brain tissue.

Incidence and characteristics of uterine leiomyomas with FDG uptake

International Nuclear Information System (INIS)

Nishizawa, Sadahiko; Inubushi, Masayuki; Kido, Aki; Miyagawa, Masao; Inoue, Takeshi; Shinohara, Katsura; Kajihara, Makoto

2008-01-01

Uterine leiomyomas sometimes show focal 18 F-fluorodeoxyglucose (FDG) uptake on positron emission tomography (PET) images that may result in a false-positive diagnosis for malignant lesions. This study was conducted to investigate the incidence and characteristics of uterine leiomyomas that showed FDG uptake. We reviewed FDG-PET and pelvic magnetic resonance (MR) images of 477 pre-menopausal (pre-MP, age 42.1±7.3 years) and 880 post-MP (age 59.9±6.8 years) healthy women who underwent these tests as parts of cancer screening. Of 1357, 323 underwent annual cancer screening four times, 97 did three times, 191 did twice, and the rest were screened once. Focal FDG uptake (maximal standardized uptake value >3.0) in the pelvis was localized and characterized on co-registered PET/MR images. Uterine leiomyomas were found in 164 pre-MP and 338 post-MP women. FDG uptake was observed in 18 leiomyomas of 17 of the 164 (10.4%) pre-MP women and in 4 leiomyomas of 4 of the 338 (1.2%) post-MP women. The incidence was significantly higher in pre-MP women than in post-MP women (chi-square, P<0.001). Of the 22, 13 showed signal intensity equal to or higher than that of the myometrium on T2-weighted MR images, which suggested abundant cellularity, whereas the majority of leiomyomas without FDG uptake showed low signal intensity. Of the 13 women, 12 examined more than twice showed substantial changes in the level of FDG uptake in leiomyomas each year with FDG uptake disappearing or newly appearing. These changes were observed frequently in relation with menopause or menstrual phases. Leiomyomas with focal FDG uptake were seen in both pre- and post-MP women with a higher incidence in pre-MP women. Abundant cellularity and hormonal dependency may explain a part of the mechanisms of FDG uptake in leiomyomas. It is important to know that the level of FDG uptake in leiomyomas can change and newly appearing FDG uptake does not necessarily mean malignant transformation. (author)

Nitrite uptake by nitrogen-depleted wheat seedlings

Energy Technology Data Exchange (ETDEWEB)

Jackson, W A; Johnson, R E; Volk, R J

1974-01-01

Intact, 14-day-old nitrogen-depleted wheat (Triticum vulgare cv. Blueboy) seedlings were exposed to solutions of 0.5 mM KNO/sub 2/, 0.05 mM CaSO/sub 4/ and 1 mM sodium 2-(N-morpholino)-ethanesulfonate, pH 6.1. Nitrite uptake was determined from depletion of the ambient solution or from incorporation of /sup 15/N in the tissue. An initial nitrite uptake shoulder was followed by a relatively slow uptake rate which subsequently increased to a substantially greater rate. This accelerated phase was maintained through 24 h. Nitrite accumulated to a slight extent in the root tissues during the first few hours but declined to low values when the accelerated rate was fully developed, indicating an increase in nitrite reductase activity paralleling the increase in nitrite uptake capacity. About 50% of the nitrogen absorbed as nitrite was translocated to the shoots by 9 to 12 h. Development of the accelerated nitrite uptake rate was restricted in excised roots, in intact plants kept in darkness, by 400 ..mu..g puromycin ml/sup -1/ and by 1 mM L-ethionine. When puromycin and L-ethionine were added after the accelerated phase had been initiated, their effects were not as detrimental as when they were added at first exposure to KNO/sub 2/. The two inhibitors restricted translocation more than uptake. The data indicate an involvement of protein synthesis and a requirement for movement of a substance from shoots to roots for maximal development of the accelerated nitrite uptake phase. A requirement for protein synthesis in the transport of soluble organic nitrogen from roots to shoots is also suggested.

Effects of blood glucose level on 18F-FDG uptake for PET/CT in normal organs: A systematic review.

Directory of Open Access Journals (Sweden)

Clarice Sprinz

Full Text Available To perform a systematic review of the effect of blood glucose levels on 2-Deoxy-2-[18F]fluoro-D-glucose (18F-FDG uptake in normal organs.We searched the MEDLINE, EMBASE and Cochrane databases through 22 April 2017 to identify all relevant studies using the keywords "PET/CT" (positron emission tomography/computed tomography, "standardized uptake value" (SUV, "glycemia," and "normal." Analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses recommendations. Maximum and mean SUVs and glycemia were the main parameters analyzed. To objectively measure the magnitude of the association between glycemia and 18F-FDG uptake in different organs, we calculated the effect size (ES and the coefficient of determination (R2 whenever possible.The literature search yielded 225 results, and 14 articles met the inclusion criteria; studies included a total of 2714 (range, 51-557 participants. The brain SUV was related significantly and inversely to glycemia (ES = 1.26; R2 0.16-0.58. Although the liver and mediastinal blood pool were significantly affected by glycemia, the magnitudes of these associations were small (ES = 0.24-0.59, R2 = 0.01-0.08 and negligible (R2 = 0.02, respectively. Lung, bone marrow, tumor, spleen, fat, bowel, and stomach 18F-FDG uptakes were not influenced by glycemia. Individual factors other than glycemia can also affect 18F-FDG uptake in different organs, and body mass index appears to be the most important of these factors.The impact of glycemia on SUVs in most organs is either negligible or too small to be clinically significant. The brain SUV was the only value largely affected by glycemia.

Reproducibility of tumor uptake heterogeneity characterization through textural feature analysis in 18F-FDG PET.

Science.gov (United States)

Tixier, Florent; Hatt, Mathieu; Le Rest, Catherine Cheze; Le Pogam, Adrien; Corcos, Laurent; Visvikis, Dimitris

2012-05-01

(18)F-FDG PET measurement of standardized uptake value (SUV) is increasingly used for monitoring therapy response and predicting outcome. Alternative parameters computed through textural analysis were recently proposed to quantify the heterogeneity of tracer uptake by tumors as a significant predictor of response. The primary objective of this study was to evaluate the reproducibility of these heterogeneity measurements. Double baseline (18)F-FDG PET scans were acquired within 4 d of each other for 16 patients before any treatment was considered. A Bland-Altman analysis was performed on 8 parameters based on histogram measurements and 17 parameters based on textural heterogeneity features after discretization with values between 8 and 128. The reproducibility of maximum and mean SUV was similar to that in previously reported studies, with a mean percentage difference of 4.7% ± 19.5% and 5.5% ± 21.2%, respectively. By comparison, better reproducibility was measured for some textural features describing local heterogeneity of tracer uptake, such as entropy and homogeneity, with a mean percentage difference of -2% ± 5.4% and 1.8% ± 11.5%, respectively. Several regional heterogeneity parameters such as variability in the intensity and size of regions of homogeneous activity distribution had reproducibility similar to that of SUV measurements, with 95% confidence intervals of -22.5% to 3.1% and -1.1% to 23.5%, respectively. These parameters were largely insensitive to the discretization range. Several parameters derived from textural analysis describing heterogeneity of tracer uptake by tumors on local and regional scales had reproducibility similar to or better than that of simple SUV measurements. These reproducibility results suggest that these (18)F-FDG PET-derived parameters, which have already been shown to have predictive and prognostic value in certain cancer models, may be used to monitor therapy response and predict patient outcome.

EFFECTS OF AMELIORANT COMPOSITIONS ON NITROGEN MINERALIZATION AND UPTAKE BY SWEET CORN IN DEGRADED PEATLAND

Directory of Open Access Journals (Sweden)

Eni Maftu’ah

2014-04-01

Full Text Available Peat soil is characterized by poor nitrogen (N availability. Ameliorants are expected to rectify this problem. This research  aimed to study the effect of ameliorant on N availability and N uptake by sweet corn plant in degraded peatland. The experiment was conducted in the greenhouse in May-July 2011 and on peatland of Kalampangan Village, Palangkaraya, Central Kalimantan in September-December 2011. Burnt peat soil of Kalampangan was used in the greenhouse experiment and sweet corn was used as an indicator plant. The treatments consisted of two factors, i.e. compositions of ameliorants by weight (A1 = 80% chicken manure + 20% dolomite; A2 = 80% local farm weed + 20% dolomite; A3 = 80% mineral soil + 20% dolomite; A4 = 20% chicken manure + 20% local farm weed + 20% residue of Chinese water chestnut (Eleocharis dulcis + 20% mineral soil + 20% dolomite; and A5 = 19% chicken manure + 71.5% mineral soil + 9.5% dolomite and rates of those ameliorants (5, 10, 15, 20 and 25 t ha-1. The experiment was arranged in a completely randomized block design with three replications. Data were collected every two weeks for five times. Observations were made on soil pH, available N (NH4+, NO3-, plant height, and N uptake in root and shoot. The results showed that  treatment A1 increased soil pH and availability of NH4+ and NO3-  in peat soils at the maximum vegetative stage. Treatment A1 provided the highest N availability and N uptake by the plant. Field experiment showed that N uptake increased  with the plant yield. Optimum yield of fresh corn cob was obtained from treatment A1 at the rate of 20 t ha-1. This research reconfirms the effectiveness of chicken manure and dolomite as peat soil ameliorant.

Uptake of Cadmium by Lemna minor, a (hyper?- accumulator plant involved in phytoremediation applications

Directory of Open Access Journals (Sweden)

Bianconi D.

2013-04-01

Full Text Available Metal pollution in waters and soils is a major environmental and human health problem. Cadmium (Cd2+ is a heavy metal displaying toxic effects in plants. In this work we studied the potentiality of Lemna minor, a monocotyledonous aquatic macrophyte, to phytoremediate cadmium-polluted waters. The plants were exposed to different cadmium concentrations 0, 13, 22 and 46μM CdSO4 for a period of 24, 48 and 72 hours. Relative growth rates (RGR, bioconcentration factor (BCF, tolerance index (Ti, cadmium uptake in whole plant and maximum efficiency of PSII (Fv/Fm were measured under controlled climate conditions. RGR, Ti and Fv/Fm declined with increasing exposure time and cadmium concentrations, while the BCF and cadmium uptake showed an opposite behavior. Data analysis of RGR, BCF, Tiand FV/FM indicates that L. minor maintains a good capacity of growth, metal bioconcentration, tolerance and efficiency of PSII up to 48h in plants exposed to 13 and 22μM CdSO4. Our results exhibited that L. minor is a good cadmium accumulator and is able to remediate Cd-polluted waters, especially at low Cd concentrations.

Maximum Acceleration Recording Circuit

Science.gov (United States)

Bozeman, Richard J., Jr.

1995-01-01

Coarsely digitized maximum levels recorded in blown fuses. Circuit feeds power to accelerometer and makes nonvolatile record of maximum level to which output of accelerometer rises during measurement interval. In comparison with inertia-type single-preset-trip-point mechanical maximum-acceleration-recording devices, circuit weighs less, occupies less space, and records accelerations within narrower bands of uncertainty. In comparison with prior electronic data-acquisition systems designed for same purpose, circuit simpler, less bulky, consumes less power, costs and analysis of data recorded in magnetic or electronic memory devices. Circuit used, for example, to record accelerations to which commodities subjected during transportation on trucks.

Neutron spectra unfolding with maximum entropy and maximum likelihood

International Nuclear Information System (INIS)

Itoh, Shikoh; Tsunoda, Toshiharu

1989-01-01

A new unfolding theory has been established on the basis of the maximum entropy principle and the maximum likelihood method. This theory correctly embodies the Poisson statistics of neutron detection, and always brings a positive solution over the whole energy range. Moreover, the theory unifies both problems of overdetermined and of underdetermined. For the latter, the ambiguity in assigning a prior probability, i.e. the initial guess in the Bayesian sense, has become extinct by virtue of the principle. An approximate expression of the covariance matrix for the resultant spectra is also presented. An efficient algorithm to solve the nonlinear system, which appears in the present study, has been established. Results of computer simulation showed the effectiveness of the present theory. (author)

Maximum Power from a Solar Panel

Directory of Open Access Journals (Sweden)

Michael Miller

2010-01-01

Full Text Available Solar energy has become a promising alternative to conventional fossil fuel sources. Solar panels are used to collect solar radiation and convert it into electricity. One of the techniques used to maximize the effectiveness of this energy alternative is to maximize the power output of the solar collector. In this project the maximum power is calculated by determining the voltage and the current of maximum power. These quantities are determined by finding the maximum value for the equation for power using differentiation. After the maximum values are found for each time of day, each individual quantity, voltage of maximum power, current of maximum power, and maximum power is plotted as a function of the time of day.

FDG uptake in the stomach

International Nuclear Information System (INIS)

Yun, M. J.; Cho, H. J.; Cho, E. H.; Kim, T. S.; Kang, W. J.; Lee, J. D.

2007-01-01

This study was performed to evaluate histopathologic features of advanced gastric cancer (AGC) to predict FDG uptake on PET. 153 patients(102 men; mean age, 55 y) were diagnosed with AGC by surgery were included in this study. PET images were evaluated by visual and semi-quantitative analysis of FDG uptake in primary tumors. Primary tumors size were measured and divided according to Borrmann classification. Tumor histology was classified under WHO classification, depth of invasion and Iymphovascular invasion. The tumors were also grouped by high cellular(cellularity = 50%) and low cellular group (<50%). Microscopic growth type was based on Lauren classification. Stromal fibrosis degree and inflammatory cell infiltration amount was graded as low(none∼mild), or high(moderate∼severe). Lymph node metastases was assessed in all patients. Statistical analyses were performed to evaluate differences in SUV as to histopathologic factors. Of the 153 patients, 21 patients(14%) had primary tumor invisible on initial whole body images. After water ingestion, the tumors became visible in 15 of the 21 patients due to disappearance of physiologic stomach uptake. Polypoid or ulcerofungating tumors, high cellularity, intestinal growth pattern, and larger tumors significantly predicted increased tumor SUVs. Well or moderately differentiated adenocarcinoma tended to show high cellularity and intestinal growth pattern. Poorly differentiated adenocarcinoma had diverse spectrum of histopathology. Signet ring cell carcinomas were mostly ulceroinfiltrative or diffusely infiltrative in macroscopic type and diffuse in microscopic tumor growth. Mucinous adenocarcinomas were mostly low in cellularity. FDG uptake patterns are useful in representing histopathologic characteristics of the entire tumor in gastric cancers. The degree of FDG uptake depends on tumor size, macroscopic type, cellularity, and microscopic growth pattern and it shows no association with well known important prognostic

Characterization of Nitrogen Uptake Pattern in Malaysian Rice MR219 at Different Growth Stages Using 15N Isotope

Directory of Open Access Journals (Sweden)

Mohammad Mu’az Hashim

2015-09-01

Full Text Available Nitrogen (N use efficiency is usually less than 50%, and it remains a major problem in rice cultivation. Controlled release fertilizer (CRF technology is one of the well-known efforts to overcome this problem. The efficiency of CRF, however, is very much dependent on the timing of nutrient release. This study was conducted to determine the precise time of N uptake by rice as a guideline to develop efficient CRF. Fertilizer N uptake by rice at different growth stages was investigated by using 15N isotopic technique. Rice was planted in pots, with 15N urea as N source at the rate of 120 kg/hm2. Potassium and phosphorus were applied at the same rate of 50 kg/hm2. Standard agronomic practices were employed throughout the growing periods. Rice plants were harvested every two weeks until maturation at the 14th week and analyzed for total N and 15N content. Nitrogen derived from fertilizer was calculated. Total N uptake in plants consistently increased until the 11th week. After that, it started to plateau and finally declined. Moreover, N utilization by rice plants peaked at 50%, which occurred during the 11th week after transplanting. N derived from fertilizer in rice plants were in the range of 18.7% to 40.0% in all plant tissues. The remaining N was derived from soil. Based on this study, N release from CRF should complete by the 11th week after planting to ensure the maximum fertilizer N uptake by rice plants. Efficient CRF should contribute to higher N derived from fertilizer which also resultedin a higher total N uptake by rice plants, increasing the potential of rice to produce higher yield while at the same time of reducing loss.

Correlation of hepatic 18F-fluorodeoxyglucose uptake with fatty liver

International Nuclear Information System (INIS)

An, Young Sil; Yoon, Joon Kee; Hong, Seon Pyo; Joh, Chul Woo; Yoon, Seok Nam

2006-01-01

Liver demonstrates heterogeneous FDG uptake and sometimes it shows abnormally increased uptake even though there is no malignant tissue. However, there was no previous study to correlate these various pattern of hepatic FDG uptake with benign liver disease. Therefore, we evaluated the significance of hepatic FDG uptake associated with various clinical factors including fatty liver, liver function tests and lipid profiles. We reviewed a total of 188 patients (male/female: 120/68, mean age: 50 ± 9) who underwent PET/CT for screening of malignancy. Patients with DM, impaired glucose tolerance, previous severe hepatic disease or long-term medication history were excluded. The FDG uptake in liver was analyzed semi-quantitatively using ROI on transaxial images (segment 8) and we compared mean standardized uptake value (SUV) between fatty liver and non-fatty liver group. We also evaluated the correlation between hepatic FDG uptake and various clinical factors including serum liver function test (ALT, AST), γ -GT, total cholesterol and triglyceride concentration. The effect of alcoholic history and body mass index on hepatic FDG uptake was analyzed within the fatty liver patients. The hepatic FDG uptake of fatty liver group was significantly higher than that of non-fatty liver group. Serum total cholesterol and triglyceride concentration showed significant correlation with hepatic FDG uptake. However, there was no significant correlation between other factors (ALT, AST, and γ -GT) and FDG uptake. Also there was no difference of mean SUV between normal and abnormal groups on the basis of alcoholic history and body mass index within fatty liver patients. Fatty liver and high serum triglyceride concentration were the independent factors affecting hepatic FDG uptake according to multivariate analysis. In conclusion, hepatic FDG uptake was strongly correlated with fatty liver and serum triglyceride concentration

CHARACTERISTICS OF MAXIMUM PERFORMANCE OF PEDALING EXERCISE IN RECUMBENT AND SUPINE POSITIONS

Directory of Open Access Journals (Sweden)

Morimasa Kato

2011-09-01

Full Text Available To determine the characteristics of maximum pedaling performance in the recumbent and supine positions, maximum isokinetic leg muscle strength was measured in eight healthy male subjects during pedaling at three velocities (300°/s, 480°/s, and 660°/s, and maximum incremental tests were performed for each position. The maximum isokinetic muscle strength in the recumbent position was 210.0 ± 29.2 Nm at 300°/s, 158.4 ± 19.8 Nm at 480°/s, and 110.6 ± 13.2 at 660°/s. In contrast, the muscle strength in the supine position was 229.3 ± 36.7 Nm at 300°/s, 180. 7 ± 20.3 Nm at 480°/s, and 129.6 ± 14.0 Nm at 660°/s. Thus, the maximum isokinetic muscle strength showed significantly higher values in the supine position than in the recumbent position at all angular velocities. The knee and hip joint angles were measured at peak torque using a goniometer; the knee joint angle was not significantly different between both positions, whereas the hip joint angle was greater in the supine position than in the recumbent position (Supine position: 137.3 ± 9. 33 degree at 300°/s, 140.0 ± 11.13 degrees at 480°/s, and 141.0 ± 9.61 degrees at 660°/s. Recumbent position: 99.5 ± 12.21 degrees at 300°/s, 101.6 ± 12.29 degrees at 480°/s, and 105.8 ± 14.28 degrees at 660°/s. Peak oxygen uptake was higher in the recumbent position (50.3 ± 4.43 ml·kg-1·min-1 than in the supine position (48.7 ± 5.10 ml·kg-1·min-1. At maximum exertion, the heart rate and whole-body rate of perceived exertion (RPE were unaffected by position, but leg muscle RPE was higher in the supine position (19.5 ± 0.53 than in the recumbent position (18.8 ± 0.71. These results suggest that the supine position is more suitable for muscle strength exertion than the recumbent position, and this may be due to different hip joint angles between the positions. On the contrary, the endurance capacity was higher in the recumbent position than in the supine position. Since leg muscle

Uptake of organic nitrogen by plants

Science.gov (United States)

Torgny Nasholm; Knut Kielland; Ulrika. Ganeteg

2009-01-01

Languishing for many years in the shadow of plant inorganic nitrogen (N) nutrition research, studies of organic N uptake have attracted increased attention during the last decade. The capacity of plants to acquire organic N, demonstrated in laboratory and field settings, has thereby been well established. Even so, the ecological significance of organic N uptake for...

Gallium 67 uptake in thymic rebound

International Nuclear Information System (INIS)

Hurst, R.; Sabio, H.; Teates, C.D.

1988-01-01

We have reported a case of localized thymic enlargement and uptake of gallium 67 in a child who had received antineoplastic chemotherapy. The enlarged thymus showed normal histology, a picture consistent with thymic rebound after nonspecific stress. This case further demonstrates the need to consider thymic rebound as a cause of gallium 67 uptake in children with neoplastic diseases

Mycorrhizal infection, phosphorus uptake, and phenology in Ranunculus adoneus: implications for the functioning of mycorrhizae in alpine systems.

Science.gov (United States)

Mullen, R B; Schmidt, S K

1993-05-01

Phosphorus levels, phenology of roots and shoots, and development of vesicular arbuscular mycorrhizal (VAM) fungi were monitored for two years in natural populations of the perennial alpine herb, Ranunculus adoneus. The purpose of this study was to understand how phosphorus uptake relates to the phenology of R. adoneus and to ascertain whether arbusculus, fungal structures used for nutrient transfer, were present when maximum phosphorus accumulation was occurring. Arbuscules were only present for a few weeks during the growing season of R. adoneus and their presence corresponded with increased phosphorus accumulation in both the roots and shoots of R. adoneus. In addition, phosphorus accumulation and peaks in mycorrhizal development occurred well after plant reproduction and most plant growth had occurred. The late season accumulation of phosphorus by mycorrhizal roots of R. adoneus is stored for use during early season growth and flowering the following spring. In this way R. adoneus can flower before soils thaw and root or mycorrhizal nutrient uptake can occur.

Difference in F-18 FDG Uptake According to the Patterns of CT-Based Diagnosed Pulmonary Lymphangitic Carcinomatosis in Patients with Lung Cancer

International Nuclear Information System (INIS)

Jun, Sung Min; Kim, Yong Ki; Kim, In Ju; Kim, Seong Jang; Nam, Hyun Yeol; Kim, Bum Soo

2008-01-01

Our purpose was to evaluate F-18 FDG uptake in pulmonary lymphangitic carcinomatosis (PLC) according to CT findings and histology of lung cancer. Thirty-three lung cancer patients with PLC were enrolled in this retrospective study. All the patients had a CT-based diagnosis of PLC. Chest CT findings of PLC were classified on the basis of involvement of axial interstitium. We categorized the involvement of axial interstitium as group 1, and the involvement of peripheral interstitium only as group 2. Visual and semiquantitative analyses by F-18 FDG PET/CT were performed in the PLC lesions. At first, we analyzed the F-18 FDG uptake in the PLC by visual assessment. If abnormal uptake was seen in the PLC, we drew regions of interest in the PLC lesions to obtain the maximum SUVs (maxSUVs). Of the 33 patients, 22 had abnormal F-18 FDG uptake in the visual assessment. There was no significant difference in the frequency of abnormal F-18 FDG uptake between group 1 and group 2 (p=0.17), although the frequency of group 1 tended to be higher than group 2 (15/19 (78.9%) in group 1, 7/14 (50.0%) in group 2). However, group 1 had a higher maxSUV than group 2 (p<0.01, group 1: 2.9±1.4, group 2: 1.5±0.6). There was no significant difference in the frequency of abnormal F-18 FDG uptake and maxSUV among the histology of the lung cancers. The involvement of axial interstitium in the PLC by lung cancer has a higher maxSUV than the involvement of only peripheral interstitium

Evaluation of a cumulative SUV-volume histogram method for parameterizing heterogeneous intratumoural FDG uptake in non-small cell lung cancer PET studies

Energy Technology Data Exchange (ETDEWEB)

Velden, Floris H.P. van; Cheebsumon, Patsuree; Yaqub, Maqsood; Hoekstra, Otto S.; Lammertsma, Adriaan A.; Boellaard, Ronald [VU University Medical Center, Department of Nuclear Medicine and PET Research, PO Box 7057, Amsterdam (Netherlands); Smit, Egbert F. [VU University Medical Center, Department of Pulmonary Diseases, Amsterdam (Netherlands)

2011-09-15

Standardized uptake values (SUV) are commonly used for quantification of whole-body [{sup 18}F]fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) studies. Changes in SUV following therapy, however, only provide a proper measure of response in case of homogeneous FDG uptake in the tumour. The purpose of this study was therefore to implement and characterize a method that enables quantification of heterogeneity in tumour FDG uptake. Cumulative SUV-volume histograms (CSH), describing % of total tumour volume above % threshold of maximum SUV (SUV{sub max}), were calculated. The area under a CSH curve (AUC) is a quantitative index of tumour uptake heterogeneity, with lower AUC corresponding to higher degrees of heterogeneity. Simulations of homogeneous and heterogeneous responses were performed to assess the value of AUC-CSH for measuring uptake and/or response heterogeneity. In addition, partial volume correction and image denoising was applied prior to calculating AUC-CSH. Finally, the method was applied to a number of human FDG scans. Partial volume correction and noise reduction improved CSH curves. Both simulations and clinical examples showed that AUC-CSH values corresponded with level of tumour heterogeneity and/or heterogeneity in response. In contrast, this correspondence was not seen with SUV{sub max} alone. The results indicate that the main advantage of AUC-CSH above other measures, such as 1/COV (coefficient of variation), is the possibility to measure or normalize AUC-CSH in different ways. AUC-CSH might be used as a quantitative index of heterogeneity in tracer uptake. In response monitoring studies it can be used to address heterogeneity in response. (orig.)

Clinical significance of abnormal nonosseous soft tissue uptake of bone tracer

International Nuclear Information System (INIS)

Zhu Bao; Shang Yukun; Li Jiannan; Bai Jing; Cai Liang

2006-01-01

Objective: To evaluate the clinical significance of abnormal soft tissue uptake of bone tracer. Methods: Thirty patients with abnormal soft tissue uptake of bone tracer on 99 Tc m -methylene diphosphonic acid (MDP) skeletal imaging were analyzed. Radioactivity of soft tissue accumulated equal to or greater than the ribs were considered as abnormal. The result was compared with pathology, MRI, CT, X-ray, ultrasound, findings for evaluating its clinical significance. Results: In 7 patients with diffuse liver uptake of 99 Tc m -MDP, 6 were massive and 1 nodular liver cancer. In 2 patients with local liver uptake, one was metastatic and the other primary liver cancer. In 5 local lung uptake cases 4 were primary lung cancer and one metastatic. In 5 cases with colonic uptake 1 was schistosomiasis while the other 4 unexplainable. Subcutaneous tissue uptake was observed in 4 patients, symmetrical uptake in 2 patients with metastatic calcification microfoci in multiple myeloma, unsymmetrical uptake in 2 patients with hemangioma and abscess. Pleural uptake in 3 patients all was metastatic cancer. Abdominal uptake in 3 patients was omentum, paravertebral soft tissue metastasis and unknown cause. Breast uptake in one patient was due to breast cancer. Conclusions: There are many causes resulting in abnormal nonosseous soft tissue uptake of 99 Tc m -MDP. The final diagnosis should correlate with clinical data and other examinations. (authors)

{sup 18}F-FDG uptake in breast cancer correlates with immunohistochemically defined subtypes

Energy Technology Data Exchange (ETDEWEB)

Koo, Hye Ryoung [Seoul National University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Hanyang University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Park, Jeong Seon [Hanyang University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Kang, Keon Wook [Seoul National University College of Medicine, Department of Nuclear Medicine, Seoul (Korea, Republic of); Cho, Nariya; Chang, Jung Min; Bae, Min Sun; Kim, Won Hwa; Lee, Su Hyun; Seo, Mirinae; Moon, Woo Kyung [Seoul National University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Kim, Mi Young [Konkuk University Medical Center, Department of Radiology, Seoul (Korea, Republic of); Kim, Jin You [Pusan National University Hospital, Department of Radiology, Pusan (Korea, Republic of)

2014-03-15

To determine whether a correlation exists between maximum standardized uptake value (SUV{sub max}) on {sup 18}F-fluorodeoxyglucose positron emission tomography (FDG-PET) and the subtypes of breast cancer. This retrospective study involved 548 patients (mean age 51.6 years, range 21-81 years) with 552 index breast cancers (mean size 2.57 cm, range 1.0-14.5 cm). The correlation between {sup 18}F-FDG uptake in PET/CT, expressed as SUV{sub max}, and immunohistochemically defined subtypes (luminal A, luminal B, human epidermal growth factor receptor 2 (HER2) positive and triple negative) was analyzed. The mean SUV{sub max} value of the 552 tumours was 6.07 ± 4.63 (range 0.9-32.8). The subtypes of the 552 tumours were 334 (60 %) luminal A, 66 (12 %) luminal B, 60 (11 %) HER2 positive and 92 (17 %) triple negative, for which the mean SUV{sub max} values were 4.69 ± 3.45, 6.51 ± 4.18, 7.44 ± 4.73 and 9.83 ± 6.03, respectively. In a multivariate regression analysis, triple-negative and HER2-positive tumours had 1.67-fold (P < 0.001) and 1.27-fold (P = 0.009) higher SUV{sub max} values, respectively, than luminal A tumours after adjustment for invasive tumour size, lymph node involvement status and histologic grade. FDG uptake was independently associated with subtypes of invasive breast cancer. Triple-negative and HER2-positive breast cancers showed higher SUV{sub max} values than luminal A tumours. circle {sup 18} F-FDG PET demonstrates increased tissue glucose metabolism, a hallmark of cancers. (orig.)

Uptake of proline by the scutellum of germinating barley grain

International Nuclear Information System (INIS)

Vaeisaenen, E.; Sopanen, T.

1986-01-01

Scutella separated from germinating grains of barley (Hordeum vulgare L. cv Himalaya) took up 1 millimolar L-[ 14 C]proline at an initial rate of about 6.5 micromoles gram -1 fresh weight hour -1 (pH 5, 30 0 C). The uptake had a pH optimum at 5. The bulk of the uptake (93%) was via carrier-mediated active transport. All of the 19 L-amino acids tested at 10 millimolar concentration inhibited the mediated uptake of 1 millimolar proline, the inhibitions varying from 18 to 76%. By studying how large a fraction of the mediated uptake was inhibitable by asparagine, alanine, glutamine, and leucine, the mediated uptake was shown to be due to three components. Two of these are most probably attributable to the two nonspecific uptake systems proposed earlier to act in the uptake of glutamine and leucine. The third component was not inhibited by glutamine, asparagine, or alanine, but was inhibited by unlabeled proline and leucine. The uptake by this system was apparently carrier-mediated active transport. D-Proline inhibited this system as strongly as L-proline. Nine of the 16 L-amino tested at 50 millimolar concentrations did not inhibit the uptake of 1 millimolar proline by this system. Valine, leucine, isoleucine, and the basic amino acids were inhibitory, but in spite of this, they did not appear to be taken up by this system. It seems therefore that in addition to two nonspecific amino acid uptake systems the scutella have an uptake system which is specific for proline. It is likely that this proline-specific system accounts for the bulk of proline uptake in a germinating grain

Quantitative 99mTc diphosphonate uptake measurements

International Nuclear Information System (INIS)

Smith, M.L.

1987-01-01

There are several different techniques currently in use for quantifying diphosphonate uptake by the skeleton. These can be considered in two main categories: local bone or whole-body uptake measurements. The choice of technique depends on the clinical problem being investigated and also on available equipment an expertise. The wide variety of approaches to diphosphonate quantitation ensures that these measurements can be obtained in almost any nuclear medicine department. This chapter discusses the general factors which may influence diphosphonate uptake measurements and outlines the techniques most relevant to current clinical practice

Experimental increase in brain HIPDM uptake by hypercapnia

International Nuclear Information System (INIS)

Karatzas, N.D.; Sfakianakis, G.N.; Pappas, D.; Duncan, R.; Heal, A.; Serafini, A.; Kung, H.F.

1988-01-01

The 30-min brain uptake of [ 125 I]HIPDM was measured in conscious rats--normocapnic (n = 8), hypercapnic (n = 12), and hyperoxic (n = 6). A mean 41.2% higher uptake was found in the brains of hypercapnic animals (p less than 0.01). In the three groups of rats, brain HIPDM uptake had a negative correlation with body weight (p less than 0.001) and a positive correlation with arterial pCO 2 (p less than 0.01), when adjusted for body weight. These results indicate that HIPDM uptake with hypercapnia may be used as a provocative test to measure cerebral blood flow reserves

Metallic mercury uptake by catalase Part 1 In Vitro metallic mercury uptake by various kind of animals' erythrocytes and purified human erythrocyte catalase

OpenAIRE

劒持,堅志

1980-01-01

The uptake of metallic mercury was studied using erythrocytes with different catalase activities taken from various kind of animals. The results were: 1) The uptake of metallic mercury by erythrocytes paralleled the activity of catalase in the erythrocytes with and without hydrogen peroxide, suggesting that the erythrocyte catalase activity is related to the uptake of metallic mercury. 2) The uptake of metallic mercury occurred not only with purified human erythrocyte catalase but also with h...

Coupling nutrient uptake and energy flow in headwater streams

Energy Technology Data Exchange (ETDEWEB)

Mulholland, Patrick J [ORNL; Fellows, Christine [Griffith University, Nathan, Queensland, Australia; Valett, H. Maurice [Virginia Polytechnic Institute and State University (Virginia Tech); Dahm, Cliff [University of New Mexico, Albuquerque; Thomas, Steve [University of Nebraska

2006-08-01

Nutrient cycling and energy flow in ecosystems are tightly linked through the metabolic processes of organisms. Greater uptake of inorganic nutrients is expected to be associated with higher rates of metabolism [gross primary production (GPP) and respiration (R)], due to assimilatory demand of both autotrophs and heterotrophs. However, relationships between uptake and metabolism should vary with the relative contribution of autochthonous and allochthonous sources of organic matter. To investigate the relationship between metabolism and nutrient uptake, we used whole-stream and benthic chamber methods to measure rates of nitrate-nitrogen (NO{sub 3}-N) uptake and metabolism in four headwater streams chosen to span a range of light availability and therefore differing rates of GPP and contributions of autochthonous carbon. We coupled whole-stream metabolism with measures of NO{sub 3}-N uptake conducted repeatedly over the same stream reach during both day and night, as well as incubating benthic sediments under both light and dark conditions. NO{sub 3}-N uptake was generally greater in daylight compared to dark conditions, and although day-night differences in whole-stream uptake were not significant, light-dark differences in benthic chambers were significant at three of the four sites. Estimates of N demand indicated that assimilation by photoautotrophs could account for the majority of NO{sub 3}-N uptake at the two sites with relatively open canopies. Contrary to expectations, photoautotrophs contributed substantially to NO{sub 3}-N uptake even at the two closed-canopy sites, which had low values of GPP/R and relied heavily on allochthonous carbon to fuel R.

The effects of water management on the CO2 uptake of Sphagnum moss in a reclaimed peatland

Directory of Open Access Journals (Sweden)

C.M. Brown

2017-07-01

Full Text Available To harvest Sphagnum on a cyclic basis and rapidly accumulate biomass, active water management is necessary. The goal of this study is to determine the hydrological conditions that will maximise CO2 uptake in Sphagnum farming basins following the moss-layer transfer technique. Plot CO2 uptake doubled from the first growing season to the second, but growth was not uniform across the site. Results indicate that the seasonal oscillations in water table (WT position were more important than actual WT position for estimating Sphagnum ground cover and CO2 uptake when the seasonal WT is shallow (< -25 cm. Plots with higher productivity had a WT range (seasonal maximum – minimum less than 15 cm, a WT position which did not fluctuate more than ± 7.5 cm, and a low WT standard deviation. Each basin was a CO2 source during the second growing season, and seasonal modelled NEE ranged from 107.1 to 266.8 g CO2 m-2. Decomposition from the straw mulch accounted for over half of seasonal respiration, and the site is expected to become a CO2 sink as the straw mulch decomposes and moss cover increases. This study highlights the importance of maintaining stable moisture conditions to increase Sphagnum growth and CO2 sink functions.

Uptake and depuration of pharmaceuticals in aquatic invertebrates

International Nuclear Information System (INIS)

Meredith-Williams, Melanie; Carter, Laura J.; Fussell, Richard; Raffaelli, David; Ashauer, Roman; Boxall, Alistair B.A.

2012-01-01

The uptake and depuration of a range of pharmaceuticals in the freshwater shrimp (Gammarus pulex) and the water boatman (Notonecta glauca) was studied. For one compound, studies were also done using the freshwater snail Planobarius corneus. In G. pulex, bioconcentration factors (BCFs) ranged from 4.6 to 185,900 and increased in the order moclobemide < 5-fluoruracil < carbamazepine < diazepam < carvedilol < fluoxetine. In N. glauca BCFs ranged from 0.1 to 1.6 and increased in the order 5-fluorouracil < carbamazepine < moclobemide < diazepam < fluoxetine < carvedilol. For P. corneus, the BCF for carvedilol was 57.3. The differences in degree of uptake across the three organisms may be due to differences in mode of respiration, behaviour and the pH of the test system. BCFs of the pharmaceuticals for each organism were correlated to the pH-corrected liposome–water partition coefficient of the pharmaceuticals. - Highlights: ► One of the first studies exploring the uptake of pharmaceuticals into aquatic invertebrates. ► Data presented on uptake, depuration rates and bioconcentration for a range of pharmaceuticals. ► Uptake is correlated with the pH-corrected liposome–water partition coefficient. ► Findings can be used to better predict impacts of pharmaceuticals on the aquatic environment. - The factors affecting the degree of uptake of pharmaceuticals into aquatic invertebrates were studied. The results indicate that species traits such as respiration and behaviour of the organisms and pH-corrected liposome–water partition coefficients are important factors in determining pharmaceutical uptake.

Uptake of inorganic contaminants by pteridophytes

International Nuclear Information System (INIS)

Zheng Jiemin; Chen Ziyuan; Tang Shirong; Guangzhou Univ., Guangzhou; Ding Bingyang

2005-01-01

The review covers results at home and abroad in terms of uptake of inorganic contaminants by pteridophytes, and suggests pteridophytes' significance in phytoremediation; the mechanisms related to uptake of inorganic contaminants by pteridophytes and some methods and means used for research on the mechanism are also introduced; the authors' viewpoints on future development trends are presented in this paper. (authors)

Radio-active iodine uptake in vitiligo

Energy Technology Data Exchange (ETDEWEB)

Kumar, V.; Shankar, V.; Chaudhary, S.; Bhatia, K.K.; Mehta, L.K.; Arora, D.R. (Medical College and Hospital, Rohtak-124001 (India))

1990-01-01

Vitiligo and thyroid disease are commonly associated disorders. Twenty-two clinically euthyroid vitiligo patients were studied for functional assessment of thyroid by radioactive iodine uptake assay. Half of them showed abnormal uptake values at 24 hours. Of these patients, 90% had lower values indicating a tendency towards developing hypothyroid state. Subclinical thyroid dysfunction in vitiligo appears to be an adaptive change. (author).

Radio-active iodine uptake in vitiligo

International Nuclear Information System (INIS)

Kumar, V.; Shankar, V.; Chaudhary, S.; Bhatia, K.K.; Mehta, L.K.; Arora, D.R.

1990-01-01

Vitiligo and thyroid disease are commonly associated disorders. Twenty-two clinically euthyroid vitiligo patients were studied for functional assessment of thyroid by radioactive iodine uptake assay. Half of them showed abnormal uptake values at 24 hours. Of these patients, 90% had lower values indicating a tendency towards developing hypothyroid state. Subclinical thyroid dysfunction in vitiligo appears to be an adaptive change. (author)

Determinants in the uptake of the human papillomavirus vaccine

DEFF Research Database (Denmark)

de Casadevante, Victoria Fernández; Cuesta, Julita Gil; Cantarero Arevalo, Lourdes

2015-01-01

of HPVV uptake in Europe. Methods: We performed a systematic Pubmed, Scopus, and Science Direct search to find articles published from HPVV availability in European countries until April 2014. No age restriction was applied. We included all studies assessing factors associated with HPVV uptake. Uptake...

Methionine Uptake and Required Radiation Dose to Control Glioblastoma

Energy Technology Data Exchange (ETDEWEB)

Iuchi, Toshihiko, E-mail: tiuchi@chiba-cc.jp [Division of Neurological Surgery, Chiba Cancer Center, Chiba (Japan); Hatano, Kazuo [Division of Radiation Oncology, Tokyo Bay Advanced Imaging and Radiation Oncology Clinic, Makuhari, Chiba (Japan); Uchino, Yoshio [Division of Nuclear Medicine, Chiba Ryogo Center, Chiba (Japan); Itami, Makiko [Division of Surgical Pathology, Chiba Cancer Center, Chiba (Japan); Hasegawa, Yuzo; Kawasaki, Koichiro; Sakaida, Tsukasa [Division of Neurological Surgery, Chiba Cancer Center, Chiba (Japan); Hara, Ryusuke [Division of Radiation Oncology, Chiba Cancer Center, Chiba (Japan)

2015-09-01

Purpose: The purpose of this study was to retrospectively assess the feasibility of radiation therapy planning for glioblastoma multiforme (GBM) based on the use of methionine (MET) positron emission tomography (PET), and the correlation among MET uptake, radiation dose, and tumor control. Methods and Materials: Twenty-two patients with GBM who underwent MET-PET prior to radiation therapy were enrolled. MET uptake in 30 regions of interest (ROIs) from 22 GBMs, biologically effective doses (BEDs) for the ROIs and their ratios (MET uptake:BED) were compared in terms of whether the ROIs were controlled for >12 months. Results: MET uptake was significantly correlated with tumor control (odds ratio [OR], 10.0; P=.005); however, there was a higher level of correlation between MET uptake:BED ratio and tumor control (OR, 40.0; P<.0001). These data indicated that the required BEDs for controlling the ROIs could be predicted in terms of MET uptake; BED could be calculated as [34.0 × MET uptake] Gy from the optimal threshold of the MET uptake:BED ratio for tumor control. Conclusions: Target delineation based on MET-PET was demonstrated to be feasible for radiation therapy treatment planning. MET-PET could not only provide precise visualization of infiltrating tumor cells but also predict the required radiation doses to control target regions.

Increased muscle glucose uptake after exercise

DEFF Research Database (Denmark)

Richter, Erik; Ploug, Thorkil; Galbo, Henrik

1985-01-01

responsiveness of glucose uptake was noted only in controls. Analysis of intracellular glucose-6-phosphate, glucose, glycogen synthesis, and glucose transport suggested that the exercise effect on responsiveness might be due to enhancement of glucose disposal. After electrical stimulation of diabetic...... of glucose. At maximal insulin concentrations, the enhancing effect of exercise on glucose uptake may involve enhancement of glucose disposal, an effect that is probably less in muscle from diabetic rats.(ABSTRACT TRUNCATED AT 250 WORDS)......It has recently been shown that insulin sensitivity of skeletal muscle glucose uptake and glycogen synthesis is increased after a single exercise session. The present study was designed to determine whether insulin is necessary during exercise for development of these changes found after exercise...

Free fatty acid has a negative correlation with myocardial uptake of FDG

Energy Technology Data Exchange (ETDEWEB)

Eo, Jae Seon; Lee, Won Woo; Park, Eun Kyung; So, Young; Lee, Dong Soo; Chung, June Key; Lee, Myung Chul; Kim, Sang Eun [College of Medicine, Seoul National University, Seoul (Korea, Republic of)

2004-07-01

Free fatty acid (FFA) is a marker of insulin resistance. Myocardial uptake of FDG is influenced by insulin resistance. We investigated the correlation of FFA and myocardial uptake of FDG in whole body PET. We measured serum FFA levels in consecutive 112 patients who underwent whole body FDG PET due to malignancy work up. Twelve patients with diabetes. 13 with liver disease, 4 with suspicious ischemic heart disease. 1 with steroid therapy, and 10 with final diagnosis of benign disease were excluded. After fasting of diet or beverages for at least 6 hours, blood was aspirated at peripheral vein for measurement of FFA and glucose in serum. FDG was injected as a dose of 0.14 mCi/kg body weight. Fifty minutes later, whole body PET scan was performed from skull base to upper thigh. Maximum SUV (maxSUV) using lean body weight was obtained in heart. liver, cerebellum, muscle and malignant tissues. Finally 72 patients (M:F 45:27, age 56.9{+-}15.8 years) were enrolled. There were 27 non small cell lung cancer, 14 lymphoma, 10 esophageal cancer, 3 breast cancer, 3 colon cancer, 3 renal cell cancer, 2 melanoma, and 10 other cancers. Serum glucose level was 96.6{+-}14.3 mg/dL. Serum FFA level was 720.0{+-}315.2 uEq/L. MaxSUV of main malignant tissue ranged from 0.7 to 11.5 (mean 4.9{+-}2.6). MaxSUV of each organs were 1.0 to 14.6 (mean 4.0{+-}3.0) in heart, 2.7 to 6.4 (mean 3.9{+-}0.6) in cerebellum, 1.0 to 2.6 (mean 1.9{+-}0.3) in liver, and 0.6 to 1.1 (mean 0.8{+-}0.1) in gluteal muscle. FFA and maxSUV of heart had a negative correlation. The best fitting line was MaxSUV of Heart = -4.4583 x In(FF A) + 32.964. But FFA had no correlation with any other parameters like serum glucose level, and MaxSUV of cerebellum, muscle, liver and malignant tissues. We found a negative correlation between FFA levels and myocardial uptake of FDG. FFA modifying drugs such as nicotinic acid derivatives may have influence on myocardial uptake of FDG.

Explaining variation in the uptake of HPV vaccination in England

Directory of Open Access Journals (Sweden)

Whynes David K

2011-03-01

Full Text Available Abstract Background In England, two national programmes of HPV vaccination for girls have been instituted, a routine programme for 12- and 13-year-olds and a catch-up programme for 17- and 18-year-olds. Uptake rates across the country have been far from uniform, and this research sought to identify factors explaining the variation in uptake by locality. Methods An association between uptake, deprivation and ethnic background had been established in pilot research. The present analysis was conducted at an aggregate, Primary Care Trust (PCT, level for the first year of the programmes. Published measures of HPV vaccination uptake, material deprivation, ethnic composition of PCT populations, primary care quality, and uptake of cervical screening and of other childhood immunisations were collated. Strong evidence of collinearity amongst the explanatory variables required a factor analysis to be undertaken. This provided four independent factors, used thereafter in regression models to explain uptake by PCT. Results The factor analysis revealed that ethnic composition was associated with attitudes towards cervical screening and other childhood vaccinations, whilst material deprivation and quality of primary care were orthogonal. Ethnic composition, early childhood vaccination, cervical screening and primary care quality were found to be influential in predicting uptake in both the routine and the catch-up cohorts, although with a lower degree of confidence in the case of the last two independent variables. Lower primary care quality was significant in explaining a greater fall in vaccination uptake between the first two doses in the catch-up cohort. Greater deprivation was a significant explanatory factor for both uptake and the fall in uptake between doses for the catch-up cohort but not for uptake in the routine cohort. Conclusion These results for uptake of the first year of the national programme using aggregate data corroborate findings from

Flavonoid rutin increases thyroid iodide uptake in rats.

Directory of Open Access Journals (Sweden)

Carlos Frederico Lima Gonçalves

Full Text Available Thyroid iodide uptake through the sodium-iodide symporter (NIS is not only an essential step for thyroid hormones biosynthesis, but also fundamental for the diagnosis and treatment of different thyroid diseases. However, part of patients with thyroid cancer is refractory to radioiodine therapy, due to reduced ability to uptake iodide, which greatly reduces the chances of survival. Therefore, compounds able to increase thyroid iodide uptake are of great interest. It has been shown that some flavonoids are able to increase iodide uptake and NIS expression in vitro, however, data in vivo are lacking. Flavonoids are polyhydroxyphenolic compounds, found in vegetables present in human diet, and have been shown not only to modulate NIS, but also thyroperoxidase (TPO, the key enzyme in thyroid hormones biosynthesis, besides having antiproliferative effect in thyroid cancer cell lines. Therefore, we aimed to evaluate the effect of some flavonoids on thyroid iodide uptake in Wistar rats in vivo. Among the flavonoids tested, rutin was the only one able to increase thyroid iodide uptake, so we decided to evaluate the effect of this flavonoid on some aspects of thyroid hormones synthesis and metabolism. Rutin led to a slight reduction of serum T4 and T3 without changes in serum thyrotropin (TSH, and significantly increased hypothalamic, pituitary and brown adipose tissue type 2 deiodinase and decreased liver type 1 deiodinase activities. Moreover, rutin treatment increased thyroid iodide uptake probably due to the increment of NIS expression, which might be secondary to increased response to TSH, since TSH receptor expression was increased. Thus, rutin might be useful as an adjuvant in radioiodine therapy, since this flavonoid increased thyroid iodide uptake without greatly affecting thyroid function.

Ficus Deltoidea Enhance Glucose Uptake Activity in Cultured Muscle Cells

International Nuclear Information System (INIS)

Zainah Adam; Shafii Khamis; Amin Ismail; Muhajir Hamid

2015-01-01

Ficus deltoidea or locally known as Mas cotek is one of the common medicinal plants used in Malaysia. Our previous studies showed that this plant have blood glucose lowering effect. Glucose uptake into muscle and adipocytes cells is one of the known mechanisms of blood glucose lowering effect. This study was performed to evaluate the effect of Ficus deltoidea on glucose uptake activity into muscle cells. The cells were incubated with Ficus deltoidea extracts either alone or combination with insulin. Amount of glucose uptake by L6 myotubes was determined using glucose tracer, 2-deoxy-(1- 3 H 1 )-glucose. The results showed that Ficus deltoidea extracts at particular doses enhanced basal or insulin-mediated glucose uptake into muscle cells significantly. Hot aqueous extract enhanced glucose uptake at the low concentration (10 μg/ ml) whereas methanolic extract enhanced glucose uptake at low and high concentrations. Methanolic extract also mimicked insulin activity during enhancing glucose uptake into L^ muscle cells. Glucose uptake activity of Ficus deltoidea could be attributed by the phenolic compound presence in the plant. This study had shown that Ficus deltoidea has the ability to enhance glucose uptake into muscle cells which is partly contributed the antidiabetic activity of this plant. (author)

Factors affecting gastric uptake in whole body FDG-PET imaging

International Nuclear Information System (INIS)

Tomemori, Takashi; Kitagawa, Mami; Nakahara, Tadaki; Wu, Jin; Nakagawa, Keiichi; Uno, Kimiichi; Abe, Kinji; Tomiyoshi, Katsumi

2001-01-01

Positron emission tomography (PET) using 2-deoxy-2-[ 18 F]-fluoro-D-glucose (FDG) is very useful for the detection and staging of tumors. However, FDG is also accumulated in the normal tissues in various degrees. This physiological FDG uptake is often seen in intestine, making confusion with malignant tumor. The aim of this study was to identify factors influencing physiological FDG uptake in the stomach. A total of 136 people who underwent cancer screening or staging of tumors except for gastric cancer using FDG whole-body PET was examined (mean age: 55.6 yrs). All subjects fasted for at least 4 hours before the PET study and were administrated with FDG intravenously (mean FDG dose: 308.9 MBq). Emission images were acquired on a whole-body PET scanner and images were reconstructed without attenuation correction. The intensity of gastric uptake of FDG whole-body PET image was visually classified into 3 grades; grade 2 = the intensity of gastric uptake more than pulmonary uptake, grade 1 = the intensity of gastric uptake equal to or less than pulmonary uptake, grade 0 = no contrast between gastric uptake and background. Twenty-eight subjects (20.6%) were classified into grade 2, 42 subjects (30.9%) were grade 1 and 66 subjects (48.5%) were grade 0. Subjects' age, fasting time, FDG dose, serum glucose level, free fatty acid level and insulin level were not significantly correlated with the intensity of gastric uptake. But the subjects with higher gastric uptake tended to have anti-Helicobactor pylori (H. pylori) antibodies. The rate of having anti-H.pylori antibodies in the grade 2 group is significantly higher than the grade 1 group (85.7% vs. 72.5%, p<0.05), and that of the grade 1 group is significantly higher than the grade 0 group (72.5% vs. 42.2%, p<0.01). Gastric uptake was observed in about half of subjects. Especially, approximately 20% of all showed high gastric uptake, which was associated with H.pylori infection. Therefore, most of the subjects with high

Factors affecting gastric uptake in whole body FDG-PET imaging

Energy Technology Data Exchange (ETDEWEB)

Tomemori, Takashi; Kitagawa, Mami; Nakahara, Tadaki; Wu, Jin; Nakagawa, Keiichi; Uno, Kimiichi; Abe, Kinji; Tomiyoshi, Katsumi [Nishidai Clinic Diagnostic Imaging Center, Tokyo (Japan)

2001-06-01

Positron emission tomography (PET) using 2-deoxy-2-[{sup 18}F]-fluoro-D-glucose (FDG) is very useful for the detection and staging of tumors. However, FDG is also accumulated in the normal tissues in various degrees. This physiological FDG uptake is often seen in intestine, making confusion with malignant tumor. The aim of this study was to identify factors influencing physiological FDG uptake in the stomach. A total of 136 people who underwent cancer screening or staging of tumors except for gastric cancer using FDG whole-body PET was examined (mean age: 55.6 yrs). All subjects fasted for at least 4 hours before the PET study and were administrated with FDG intravenously (mean FDG dose: 308.9 MBq). Emission images were acquired on a whole-body PET scanner and images were reconstructed without attenuation correction. The intensity of gastric uptake of FDG whole-body PET image was visually classified into 3 grades; grade 2 = the intensity of gastric uptake more than pulmonary uptake, grade 1 = the intensity of gastric uptake equal to or less than pulmonary uptake, grade 0 = no contrast between gastric uptake and background. Twenty-eight subjects (20.6%) were classified into grade 2, 42 subjects (30.9%) were grade 1 and 66 subjects (48.5%) were grade 0. Subjects' age, fasting time, FDG dose, serum glucose level, free fatty acid level and insulin level were not significantly correlated with the intensity of gastric uptake. But the subjects with higher gastric uptake tended to have anti-Helicobactor pylori (H. pylori) antibodies. The rate of having anti-H.pylori antibodies in the grade 2 group is significantly higher than the grade 1 group (85.7% vs. 72.5%, p<0.05), and that of the grade 1 group is significantly higher than the grade 0 group (72.5% vs. 42.2%, p<0.01). Gastric uptake was observed in about half of subjects. Especially, approximately 20% of all showed high gastric uptake, which was associated with H.pylori infection. Therefore, most of the subjects

MAXIMUM NUMBER OF REPETITIONS, TOTAL WEIGHT LIFTED AND NEUROMUSCULAR FATIGUE IN INDIVIDUALS WITH DIFFERENT TRAINING BACKGROUNDS

Directory of Open Access Journals (Sweden)

Valeria Panissa

2013-04-01

Full Text Available The aim of this study was to evaluate the performance, as well as neuromuscular activity, in a strength task in subjects with different training backgrounds. Participants (n = 26 were divided into three groups according to their training backgrounds (aerobic, strength or mixed and submitted to three sessions: (1 determination of the maximum oxygen uptake during the incremental treadmill test to exhaustion and familiarization of the evaluation of maximum strength (1RM for the half squat; (2 1RM determination; and (3 strength exercise, four sets at 80�0of the 1RM, in which the maximum number of repetitions (MNR, the total weight lifted (TWL, the root mean square (RMS and median frequency (MF of the electromyographic (EMG activity for the second and last repetition were computed. There was an effect of group for MNR, with the aerobic group performing a higher MNR compared to the strength group (P = 0.045, and an effect on MF with a higher value in the second repetition than in the last repetition (P = 0.016. These results demonstrated that individuals with better aerobic fitness were more fatigue resistant than strength trained individuals. The absence of differences in EMG signals indicates that individuals with different training backgrounds have a similar pattern of motor unit recruitment during a resistance exercise performed until failure, and that the greater capacity to perform the MNR probably can be explained by peripheral adaptations.

Nitrogen and phosphorus uptake in two Idaho (USA) headwater wilderness streams.

Science.gov (United States)

Davis, Jeffrey C; Minshall, G Wayne

1999-05-01

Nitrate and phosphate solutions were released into two reaches of two central Idaho streams to determine within- and between-stream variability in uptake lengths, uptake rates, and mass transfer coefficients. Physical and biotic stream characteristics and periphyton nitrate-uptake rates in recirculating chambers were measured to determine their influence on nutrient dynamics. Phosphate uptake length did not differ among the four reaches. There were no within-stream differences in nitrate uptake lengths but they did differ between the two streams. Long nitrate uptake lengths likely were due to instream concentrations above saturation but also may have been influenced by differences in active surface area and algal abundance. Nitrate and phosphate uptake lengths were longer, and uptake rates higher, than most other published values. However, mass transfer coefficients were comparable to measurements in other streams. Mass transfer coefficients may be a better parameter for temporal and spatial comparisons of instream nutrient dynamics, and for determining the underlying causes of variability in uptake length.

Bacterial uptake of photosynthetic carbon from freshwater phytoplankton

International Nuclear Information System (INIS)

Coveney, M.F.

1982-01-01

Microheterotrophic uptake of algal extracellular products was studied in two eutrophic lakes in southern Sweden. Size fractionation was used in H 14 CO 3 uptake experiments to measure 14 C fixation in total particulate, small particulate and dissolved organic fractions. Carbon fixed in algal photosynthesis was recovered as dissolved and small particulate 14 C, representing excretion and bacterial uptake of algal products. Estimated gross extracellular release was low in these eutrophic systems, 1 to 7% of total 14 C uptake per m 2 lake surface. From 28 to 80 % of 14 C released was recovered in the small particulate fraction after ca. 4h incubation.This percentage was uniform within each depth profile, but varied directly with in situ water temperature. Laboratory time-series incubations indicated steady state for the pool of algal extracellular products on one occasion, while increasing pool size was indicated in the remaining two experiments. Uptake of photosynthetic carbon to small particles in situ was 32 to 95% of estimted heterotrophic bacterial production (as dark 14 CO 2 uptake) on four occasions. While excretion apparently was not an important loss of cabon for phytoplankton, it may have represented an important carbon source for planktonic bacteria. (author)

Bibliographical survey of radiostrontium uptake capacity and processes in aquatic plants

International Nuclear Information System (INIS)

Pally, M.; Foulquier, L.

1983-09-01

This report covers 302 articles published between 1949 and 1980 on the contamination of freshwater and marine aquatic plants by radioactive strontium. For the marine and continental environments, the results of laboratory experiments on the dynamics of radiostrontium buildup and localization, concentration factors, elimination processes, the effects of biological factors and of the environment, the activity levels and concentration factors measured in areas directly and indirectly affected by waste discharges, discrimination factors and the role of plants as radiation indicators, are examined. The radioactive strontium uptake potentials are higher for freshwater plants -especially mosses and characeae- than for marine plants. In zones not directly affected by waste discharges, the maximum activity measured is 82 pCi/kg wet weight, compared with 750 pCi/kg for freshwater plants. The peak values were observed in 1964-1965. In zones directly affected by waste discharges, the activity levels range from 15 to 1700 pCi of 90 Sr per kilogram of wet weight in the marine environment, and from 20 to 207000 pCi/kg in fresh water. This work underlines the need for greater accuracy in allowing for the ecological characteristics of each site when assessing the impact of nuclear facilities, and for thoroughly correlating field observations with laboratory experiments in order to obtain a prospective view of the potentials for radioactive strontium uptake by plants according to the activity levels present in the liquid effluents [fr

Lactate, Glucose and Oxygen Uptake in Human Brain During Recovery from Maximal Exercise

DEFF Research Database (Denmark)

Kojiro, I.; Schmalbruch, I.K.; Quistorff, B.

1999-01-01

Skeletal muscle, brain lactate uptake, brain oxygen uptake, energy metabolism, brain glucose uptake......Skeletal muscle, brain lactate uptake, brain oxygen uptake, energy metabolism, brain glucose uptake...

Physiological FDG uptake in the ovaries after hysterectomy

International Nuclear Information System (INIS)

Nishizawa, Sadahiko; Inubushi, Masayuki; Ozawa, Fukujiro; Kido, Aki; Okada, Hiroyuki

2007-01-01

It is known that focal 18 F-fluorodeoxyglucose (FDG) uptake is physiologically seen in the ovaries and uterus of premenopausal women in correlation with the menstrual cycle, which may cause false-positive diagnoses on the images of FDG positron emission tomography (PET). The objective of this study was to clarify whether women of reproductive age after hysterectomy whose ovaries were preserved, also showed physiological ovarian FDG uptake. We reviewed 26 women after hysterectomy (age 51.1±5.0 years), who underwent annual cancer screening, including FDG-PET and pelvic magnetic resonance (MR) imaging, three times. Seven women (age 45.9±5.8 years, range 34-52 years) had at least one ovary, showing changes in its appearance including the size and number of follicles on MR images each year, which suggested that the ovary was functioning. Four of the seven women showed focal FDG uptake (standardized uptake value 4.2±1.1) that corresponded to the normal ovaries on five PET examinations. Another group of 19 women (age 53.1±3.1 years, range 47-59 years) who had small ovaries without changes on MR images each year did not show FDG uptake in the ovaries. Physiological FDG uptake observed in the ovaries of women of reproductive age even after hysterectomy is reasonably common. As it is not easy to determine the hormonal cycle in these women, it is essential to correlate focal FDG uptake in the pelvis with anatomical and morphological findings on MR images to avoid false-positive diagnoses. (author)

Heavy metal uptake of Geosiphon pyriforme

Energy Technology Data Exchange (ETDEWEB)

Scheloske, Stefan E-mail: stefan.scheloske@mpi-hd.mpg.de; Maetz, Mischa; Schuessler, Arthur

2001-07-01

Geosiphon pyriforme represents the only known endosymbiosis between a fungus, belonging to the arbuscular mycorrhizal (AM) fungi, and cyanobacteria (blue-green algae). Therefore we use Geosiphon as a model system for the widespread AM symbiosis and try to answer some basic questions regarding heavy metal uptake or resistance of AM fungi. We present quantitative micro-PIXE measurements of a set of heavy metals (Cu, Cd, Tl, Pb) taken up by Geosiphon-cells. The uptake is studied as a function of the metal concentration in the nutrient solution and of the time Geosiphon spent in the heavy metal enriched medium. The measured heavy metal concentrations range from several ppm to some hundred ppm. Also the influence of the heavy metal uptake on the nutrition transfer of other elements will be discussed.

FDG uptake heterogeneity in FIGO IIb cervical carcinoma does not predict pelvic lymph node involvement.

Science.gov (United States)

Brooks, Frank J; Grigsby, Perry W

2013-12-23

Many types of cancer are located and assessed via positron emission tomography (PET) using the 18F-fluorodeoxyglucose (FDG) radiotracer of glucose uptake. There is rapidly increasing interest in exploiting the intra-tumor heterogeneity observed in these FDG-PET images as an indicator of disease outcome. If this image heterogeneity is of genuine prognostic value, then it either correlates to known prognostic factors, such as tumor stage, or it indicates some as yet unknown tumor quality. Therefore, the first step in demonstrating the clinical usefulness of image heterogeneity is to explore the dependence of image heterogeneity metrics upon established prognostic indicators and other clinically interesting factors. If it is shown that image heterogeneity is merely a surrogate for other important tumor properties or variations in patient populations, then the theoretical value of quantified biological heterogeneity may not yet translate into the clinic given current imaging technology. We explore the relation between pelvic lymph node status at diagnosis and the visually evident uptake heterogeneity often observed in 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) images of cervical carcinomas. We retrospectively studied the FDG-PET images of 47 node negative and 38 node positive patients, each having FIGO stage IIb tumors with squamous cell histology. Imaged tumors were segmented using 40% of the maximum tumor uptake as the tumor-defining threshold and then converted into sets of three-dimensional coordinates. We employed the sphericity, extent, Shannon entropy (S) and the accrued deviation from smoothest gradients (ζ) as image heterogeneity metrics. We analyze these metrics within tumor volume strata via: the Kolmogorov-Smirnov test, principal component analysis and contingency tables. We found no statistically significant difference between the positive and negative lymph node groups for any one metric or plausible combinations thereof. Additionally

FDG uptake heterogeneity in FIGO IIb cervical carcinoma does not predict pelvic lymph node involvement

International Nuclear Information System (INIS)

Brooks, Frank J; Grigsby, Perry W

2013-01-01

Many types of cancer are located and assessed via positron emission tomography (PET) using the 18F-fluorodeoxyglucose (FDG) radiotracer of glucose uptake. There is rapidly increasing interest in exploiting the intra-tumor heterogeneity observed in these FDG-PET images as an indicator of disease outcome. If this image heterogeneity is of genuine prognostic value, then it either correlates to known prognostic factors, such as tumor stage, or it indicates some as yet unknown tumor quality. Therefore, the first step in demonstrating the clinical usefulness of image heterogeneity is to explore the dependence of image heterogeneity metrics upon established prognostic indicators and other clinically interesting factors. If it is shown that image heterogeneity is merely a surrogate for other important tumor properties or variations in patient populations, then the theoretical value of quantified biological heterogeneity may not yet translate into the clinic given current imaging technology. We explore the relation between pelvic lymph node status at diagnosis and the visually evident uptake heterogeneity often observed in 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) images of cervical carcinomas. We retrospectively studied the FDG-PET images of 47 node negative and 38 node positive patients, each having FIGO stage IIb tumors with squamous cell histology. Imaged tumors were segmented using 40% of the maximum tumor uptake as the tumor-defining threshold and then converted into sets of three-dimensional coordinates. We employed the sphericity, extent, Shannon entropy (S) and the accrued deviation from smoothest gradients (ζ) as image heterogeneity metrics. We analyze these metrics within tumor volume strata via: the Kolmogorov-Smirnov test, principal component analysis and contingency tables. We found no statistically significant difference between the positive and negative lymph node groups for any one metric or plausible combinations thereof. Additionally

Maximum concentrations at work and maximum biologically tolerable concentration for working materials 1991

International Nuclear Information System (INIS)

1991-01-01

The meaning of the term 'maximum concentration at work' in regard of various pollutants is discussed. Specifically, a number of dusts and smokes are dealt with. The valuation criteria for maximum biologically tolerable concentrations for working materials are indicated. The working materials in question are corcinogeneous substances or substances liable to cause allergies or mutate the genome. (VT) [de

Selective uptake of manganese in seawater by hybrid microcapsules

International Nuclear Information System (INIS)

Kuzumaki, Takenori; Yan, Wu; Mimura, Hitoshi; Niibori, Yuichi

2008-01-01

The selective separation and recovery of low concentrated elements in seawater are very important subjects for the advancement of environmental monitoring. Selective uptake of manganese from seawater was carried out by using two kinds of microcapsules (MCs) including activated carbon (AC) and insoluble tannin (T). The adsorbents, AC and T, having affinity for manganese, were enclosed into MCs (ACMS, TMC) by sol-gel method using matrices of biopolymer (calcium alginate gel polymer, CaALG). The uptake properties and selectivity of Mn 2+ (1 ppm) for MCs were examined by batch method. Relatively large uptake percentages of Mn 2+ above 80% were obtained within 1 h, and the uptake percentage above 80% was kept at pH 3-6. The uptake order was found to be T, AC, CaALG > ACMC, TMC. The uptake of Mn 2+ decreased with increasing Na + ion concentration. This tendency depends on the swelling property of CaALG; it tends to solate in the presence of highly concentrated Na + ions. The manganese ions were adsorbed on CaALG, ACMC and TMC from seawater containing 1,000 ppm Mn 2+ . ACMC and TMC had selectivity to Mn 2+ , and, especially, the matrices of CaALG also had an excellent uptake and selectivity properties. (author)

Selenium Uptake and Volatilization by Marine Algae

Science.gov (United States)

Luxem, Katja E.; Vriens, Bas; Wagner, Bettina; Behra, Renata; Winkel, Lenny H. E.

2015-04-01

Selenium (Se) is an essential trace nutrient for humans. An estimated one half to one billion people worldwide suffer from Se deficiency, which is due to low concentrations and bioavailability of Se in soils where crops are grown. It has been hypothesized that more than half of the atmospheric Se deposition to soils is derived from the marine system, where microorganisms methylate and volatilize Se. Based on model results from the late 1980s, the atmospheric flux of these biogenic volatile Se compounds is around 9 Gt/year, with two thirds coming from the marine biosphere. Algae, fungi, and bacteria are known to methylate Se. Although algal Se uptake, metabolism, and methylation influence the speciation and bioavailability of Se in the oceans, these processes have not been quantified under environmentally relevant conditions and are likely to differ among organisms. Therefore, we are investigating the uptake and methylation of the two main inorganic Se species (selenate and selenite) by three globally relevant microalgae: Phaeocystis globosa, the coccolithophorid Emiliania huxleyi, and the diatom Thalassiosira oceanica. Selenium uptake and methylation were quantified in a batch experiment, where parallel gas-tight microcosms in a climate chamber were coupled to a gas-trapping system. For E. huxleyi, selenite uptake was strongly dependent on aqueous phosphate concentrations, which agrees with prior evidence that selenite uptake by phosphate transporters is a significant Se source for marine algae. Selenate uptake was much lower than selenite uptake. The most important volatile Se compounds produced were dimethyl selenide, dimethyl diselenide, and dimethyl selenyl sulfide. Production rates of volatile Se species were larger with increasing intracellular Se concentration and in the decline phase of the alga. Similar experiments are being carried out with P. globosa and T. oceanica. Our results indicate that marine algae are important for the global cycling of Se

[Long-Term Inhibition of FNA on Aerobic Phosphate Uptake and Variation of Phosphorus Uptake Properties of the Sludge].

Science.gov (United States)

Ma, Juan; Li, Lu; Yu, Xiao-jun; Sun, Lei-jun; Sun, Hong-wei; Chen, Yong-zhi

2015-10-01

An alternating anaerobic/oxic ( An/O) sequencing batch reactor (SBR) was employed to investigate the long-term inhibitory effect of free nitrous acid (FNA) on aerobic phosphorus uptake performance and variation of phosphorus uptake properties of the sludge by adding nitrite. The reactor was started up under the condition of 21-23 degrees C. The results showed that FNA had no impact on phosphate release and uptake capacities of the sludge. However, the specific phosphate release/uptake rates was found to be higher. As FNA concentration (measure by HNO2-N) was lower than 0.53 x 10(-3) mg x L(-1), phosphorus removal efficiency of the system was higher than 96.9%. When the FNA concentration was increased to 0.99 x 10(-3) mg x L(-1), 1.46 x 10(-3) mg x L(-1) and 1.94 x 10(-3) mg x L(-1), the phosphorus removal performance deteriorated rapidly. The phosphorus removal efficiency was recovered to 64.42%, 67.33% and 44.14% after 50, 12 and 30 days, respectively, which implied the deterioration of phosphorus removal performance caused by FNA inhibition could be recovered and long-term acclimation could shorten the recovery process. Notably, increasing nitrite consumption appeared during aerobic phase with the concentration of FNA below 1.46 x 10(-3) mg x L(-1). It was also observed that the phosphorus uptake properties of the sludge varied after long-term inhibition. Nitrate and nitrite type anoxic phosphorus uptake capacity was increased by 3.35 and 3.86 times, respectively, suggesting long-term dosing FNA may facilitate the denitrifying of polyphosphate in organisms utilizing nitrite as electron acceptor. Moreover, long-term acclimation favored sludge settling.

40 CFR 1042.140 - Maximum engine power, displacement, power density, and maximum in-use engine speed.

Science.gov (United States)

2010-07-01

... cylinders having an internal diameter of 13.0 cm and a 15.5 cm stroke length, the rounded displacement would... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Maximum engine power, displacement... Maximum engine power, displacement, power density, and maximum in-use engine speed. This section describes...

The role of skeletal blood flow in determining the uptake of sup(99m)Tc-methylene diphosphonate

International Nuclear Information System (INIS)

McCarthy, I.D.; Hughes, S.P.F.

1983-01-01

The increased uptake of bone-seeking radionuclides following a fracture has been stated to be due to an increase in bone blood flow, resulting in an increase in capillary surface area available for exchange. This paper examines the relationship between the maximum instantaneous extraction of sup(99m)Tc-MDP and blood flow in normal canine tibia. The findings, consistent with the model of capillary action proposed for muscle by Renkin and Crone, are applicable to bone. There is no evidence that in normal bone the surface area available for exchange responds to an increase in bone blood flow. (orig.)

Credal Networks under Maximum Entropy

OpenAIRE

Lukasiewicz, Thomas

2013-01-01

We apply the principle of maximum entropy to select a unique joint probability distribution from the set of all joint probability distributions specified by a credal network. In detail, we start by showing that the unique joint distribution of a Bayesian tree coincides with the maximum entropy model of its conditional distributions. This result, however, does not hold anymore for general Bayesian networks. We thus present a new kind of maximum entropy models, which are computed sequentially. ...

Gallium-67 uptake in meningeal sarcoidosis

International Nuclear Information System (INIS)

Ayres, J.G.; Hicks, B.H.; Maisey, M.N.

1986-01-01

A case of sarcoidosis limited to the central nervous system is described in which the diagnosis was suggested by high Ga-67 uptake in the cranial and spinal meninges. The diagnosis was confirmed by meningeal biopsy. Treatment with oral corticosteroids resulted in clinical improvement and marked reduction in Ga-67 uptake in the meninges. This is the first reported case of the central nervous system sarcoid diagnosed by Ga-67 imaging

The uptake of radionuclides by plants

International Nuclear Information System (INIS)

Cawse, P.A.; Turner, G.S.

1982-02-01

A review of the literature, since 1970, on the research into the uptake of radionuclides by plants, with references to earlier soil and plant studies on the fate of nuclear weapons fallout. Experimental data on the uptake of plutonium isotopes, americium 241, cesium 137, radium 226, curium 244 and neptunium 237 and details of the chemical form of the radionuclide, soil type and plant growth period are tabulated. (U.K.)

18 F-FDG uptake in focal organising pneumonia mimicking bronchial carcinoma.

Science.gov (United States)

Baha, Ayse; Yildirim, Fatma; Kokturk, Nurdan; Akdemir, Umit Ozgur; Demircan, Sedat; Turktas, Haluk

2016-11-01

Organising pneumonia (OP) is not a well-known cause of increased 18 F-FDG uptake, and the relationship of the increased 18 F-FDG uptake to clinical parameters has not been clearly identified. This study aims to assess the role of positron emission tomography-computed tomography (PET-CT) for the diagnosis of focal organised pneumonia that may mimic malignity because of mass-like lesions on the radiological images it causes. Among 40 patients of whom histopathological exams were consistent with OP, medical records of 14 focal OP patients diagnosed with surgical biopsy were evaluated retrospectively. There were 10 male (71.4%) and 4 female (28.6%) patients. The mean age at the time of diagnosis was 57.2 ± 11.7 years, ranging from 38 to 85 years. Nine subjects (64.3%) were smokers. Eleven patients (78.5%) had symptoms, the remaining 3 patients (21.5%) were asymptomatic. Three patients (21.3%) had a history of malignancy. Focal lung lesion was initially detected by chest radiography in 10 patients (71.4%) and by computed tomography (CT) scan in all patients. CT scan showed a single lesion in 12 (85.7%) patients. The lesions were located in the right lung of the half of patients (50%) and in the left lung of the other half. The median diameter of the lesions was 3.4 cm (range, 1.8-6.0 cm). PET with 18 F-FDG was performed in all patients, and hypermetabolic activity of the focal lung lesion was demonstrated in all cases. The median values of maximum standardized uptake value was 3.5 ± 2.7 (min 2.1-max 13.1). Focal OP is a discrete form of OP that is associated with unifocal lesions on radiological images, and it can easily mimic lung cancer because of positivity on PET scans. There are no specific findings of PET scan for the diagnosis of OP. © 2015 John Wiley & Sons Ltd.

Thyroid uptake of I-131 during anti-thyroid drug treatment

International Nuclear Information System (INIS)

Hoque, M.; Alam, F.; Haque, F.S.; Karim, M.A.; Fariduddin, M.

2004-01-01

Hyperthyroidism is a global ailment and its treatment is very promising either by ant-thyroid drug or by radioiodine. Iodine-131 uptake test is very important for evaluation of hyperthyroid in respect to its therapy and to exclude thyroiditis. This study was performed to observe the thyroid uptake pattern during intake of anti-thyroid medicine and workout the possibility to start I-131 therapy just after withdraw of antithyroid drug without waiting few days. In this study total 252 patient's I-131 uptake test is performed. Among the patient 135 (53.57%) were female, 117 (64.43%) were male. All this patients were hyperthyroid both clinically and biochemically. Thyroid uptake was taken to all patients at 24 hours after oral administration of 5 to 10 micro-curie of I -131. Uptake was taken by an uptake system and recorded as percentage uptake. These patients are grouped into three categories. Group-A-newly diagnosed cases, who have not taken antithyroid drug or I-131 therapy, there were 82 patients in this group, and their mean uptake was 37.12 ±18.5%. Group B - this group of patients were studied during intake of antithyroid medicine, there were 130 patients in this group and their mean uptake was 34.34±16.0%. Group-B patients were further divided in two sub-groups, patients having antithyroid drug for 1 to 3 weeks (group-B 1), group B1 have mean uptake 37±21% and those were taking antithyroid for 3 weeks to 2 years (group-B2), group B2 have uptake 34.34±20%. Group C- these patients are taken from those patients who had withdrawn antithyroid drug for 3 days to 3 months, there were 40 such patients. Group C further divided into two sub-group, group-C1 (stopped for 3-10 days) and group C2 (stopped for 11 days to 3 months). Group C1 had mean uptake 38±16% and group C2 had mean uptake 35±19%. From this study it is observed that Iodine-131 uptake percentage of untreated hyperthyroid; during antithyroid drug treatment and after withdraw of antithyroid drug almost

Retinal uptake and release of (/sup 3/H)DABA

Energy Technology Data Exchange (ETDEWEB)

Bauer, B; Ehinger, B [Lund Univ. (Sweden)

1978-03-01

The uptake of (/sup 3/H)DABA was studied in rat, guinea-pig and cat retinas in vivo and in rabbit retinas both in vivo and in vitro by autoradiography. (/sup 3/H)DABA was preferentially accumulated by a type of amacrine cell but after brief incubation or shortly after intravitreal injections there was not only a neuronal uptake but also a glial one. In guinea-pigs the glial labelling in vivo was significant also after 4 hr. The glial uptake (rabbits) was found to be saturable and temperature dependent as expected for an active uptake mechanism. The Ksub(m) of DABA uptake was 2.11 x 10/sup -5/ m and Vsub(max) 2.38 x 10/sup -5/ mol/mg/min. GABA competitively inhibited the DABA uptake. The uptake was not statistically significantly influenced by OMEGA-amino acids such as glycine, ..beta..-alanine, ..cap alpha..-alanine or epsilon-aminocaproic acid. The effect of different stimuli on the spontaneous efflux of radioactivity from (/sup 3/H)DABA preloaded rabbit retinas was studied with (/sup 3/H)DABA localized to neurons. Light flashes evoked a small but not statistically significant increased release whereas 40mM-K/sup +/ evoked an immediate and large increase. Unlabelled DABA, GABA and ..beta..-alanine (10/sup -5/M) increased the spontaneous efflux of (/sup 3/H)DABA but not glycine. It is concluded that there is in the retina of rats, guinea-pigs, cats, and rabbits, a glial high affinity uptake mechanism in addition to the neuronal uptake. DABA seems to be transported by the same mechanism as GABA in both systems. The DABA seems to be better retained in neurons than in glia in rats, cats and rabbits, which allows it to be used as a neuronal marker.

Maximum Entropy in Drug Discovery

Directory of Open Access Journals (Sweden)

Chih-Yuan Tseng

2014-07-01

Full Text Available Drug discovery applies multidisciplinary approaches either experimentally, computationally or both ways to identify lead compounds to treat various diseases. While conventional approaches have yielded many US Food and Drug Administration (FDA-approved drugs, researchers continue investigating and designing better approaches to increase the success rate in the discovery process. In this article, we provide an overview of the current strategies and point out where and how the method of maximum entropy has been introduced in this area. The maximum entropy principle has its root in thermodynamics, yet since Jaynes’ pioneering work in the 1950s, the maximum entropy principle has not only been used as a physics law, but also as a reasoning tool that allows us to process information in hand with the least bias. Its applicability in various disciplines has been abundantly demonstrated. We give several examples of applications of maximum entropy in different stages of drug discovery. Finally, we discuss a promising new direction in drug discovery that is likely to hinge on the ways of utilizing maximum entropy.

Modeling uptake kinetics of cadmium by field-grown lettuce

Energy Technology Data Exchange (ETDEWEB)

Chen Weiping [Department of Environmental Sciences, University of California, 900 University Avenue, Riverside, CA 92521 (United States)], E-mail: chenweip@yahoo.com.cn; Li Lianqing [Institute of Resources, Ecosystem and Environment of Agriculture, Nanjing Agricultural University, Nanjing 210095 (China); Chang, Andrew C.; Wu Laosheng [Department of Environmental Sciences, University of California, 900 University Avenue, Riverside, CA 92521 (United States); Kwon, Soon-Ik [Agricultural Environmental and Ecology Division, National Institute of Agricultural Science and Technology, Suwon 441-707 (Korea, Republic of); Bottoms, Rick [Desert Research and Extension Center, 1004 East Holton Road, El Centro, CA 92243 (United States)

2008-03-15

Cadmium uptake by field grown Romaine lettuce treated with P-fertilizers of different Cd levels was investigated over an entire growing season. Results indicated that the rate of Cd uptake at a given time of the season can be satisfactorily described by the Michaelis-Menten kinetics, that is, plant uptake increases as the Cd concentration in soil solution increases, and it gradually approaches a saturation level. However, the rate constant of the Michaelis-Menten kinetics changes over the growing season. Under a given soil Cd level, the cadmium content in plant tissue decreases exponentially with time. To account for the dynamic nature of Cd uptake, a kinetic model integrating the time factor was developed to simulate Cd plant uptake over the growing season: C{sub Plant} = C{sub Solution} . PUF{sub max} . exp[-b . t], where C{sub Plant} and C{sub Solution} refer to the Cd content in plant tissue and soil solution, respectively, PUF{sub max} and b are kinetic constants. - A kinetic model was developed to evaluate the uptake of Cd under field conditions.

Modeling uptake kinetics of cadmium by field-grown lettuce

International Nuclear Information System (INIS)

Chen Weiping; Li Lianqing; Chang, Andrew C.; Wu Laosheng; Kwon, Soon-Ik; Bottoms, Rick

2008-01-01

Cadmium uptake by field grown Romaine lettuce treated with P-fertilizers of different Cd levels was investigated over an entire growing season. Results indicated that the rate of Cd uptake at a given time of the season can be satisfactorily described by the Michaelis-Menten kinetics, that is, plant uptake increases as the Cd concentration in soil solution increases, and it gradually approaches a saturation level. However, the rate constant of the Michaelis-Menten kinetics changes over the growing season. Under a given soil Cd level, the cadmium content in plant tissue decreases exponentially with time. To account for the dynamic nature of Cd uptake, a kinetic model integrating the time factor was developed to simulate Cd plant uptake over the growing season: C Plant = C Solution . PUF max . exp[-b . t], where C Plant and C Solution refer to the Cd content in plant tissue and soil solution, respectively, PUF max and b are kinetic constants. - A kinetic model was developed to evaluate the uptake of Cd under field conditions

Maximum Quantum Entropy Method

OpenAIRE

Sim, Jae-Hoon; Han, Myung Joon

2018-01-01

Maximum entropy method for analytic continuation is extended by introducing quantum relative entropy. This new method is formulated in terms of matrix-valued functions and therefore invariant under arbitrary unitary transformation of input matrix. As a result, the continuation of off-diagonal elements becomes straightforward. Without introducing any further ambiguity, the Bayesian probabilistic interpretation is maintained just as in the conventional maximum entropy method. The applications o...

Uptake, accumulation and metabolic response of ferricyanide in weeping willows.

Science.gov (United States)

Yu, Xiao-Zhang; Gu, Ji-Dong

2009-01-01

The remediation potential and metabolic responses of plants to ferricyanide were investigated using pre-rooted weeping willows (Salix babylonica L.) grown hydroponically in growth chambers and treated with potassium ferricyanide. Positive responses were observed for the plants exposed to cyanide recovered in plant biomass was constant in all treatments, indicating that transport is a major limiting step for the uptake of ferricyanide by plants. The majority of the ferricyanide taken up from the growth media was possibly assimilated during transport through plants. The velocity of the removal processes can be described by Michaelis-Menten kinetics, and the half-saturation constant (K(M)) and the maximum removal capacity (v(max)) were estimated to be 228.1 mg CN L(-1) and 36.43 mg CN kg(-1) d(-1), respectively, using non-linear regression methods. These results suggest that weeping willows can take up, transport and assimilate ferricyanide; and phytoremediation is an option for cleaning up the environmental sites contaminated with cyanide complexes.

Menadione inhibits MIBG uptake in two neuroendocrine cell lines

NARCIS (Netherlands)

Cornelissen, J.; Tytgat, G. A.; van den Brug, M.; van Kuilenburg, A. B.; Voûte, P. A.; van Gennip, A. H.

1997-01-01

In this paper we report on our studies of the effect of menadione on the uptake of MIBG in the neuroendocrine cell lines PC12 and SK-N-SH. Menadione inhibits the uptake of MIBG in both cell lines in a dose-dependent manner. Inhibition of MIBG uptake is most pronounced in the PC12 cell line.

[Increased glucose uptake by seborrheic keratosis on PET scan].

Science.gov (United States)

Merklen-Djafri, C; Truntzer, P; Hassler, S; Cribier, B

2017-05-01

Positron emission tomography (PET) is an examination based upon the uptake of a radioactive tracer by hypermetabolic cells. It is primarily used in tandem with tomodensitometry (PET-TDM) for cancer staging because of its high sensitivity and specificity for the detection of metastases. However, unusually high uptake may occur with benign tumours, including skin tumours. Herein, we report an extremely rare case of pathological uptake levels resulting from seborrhoeic keratosis. A 55-year-old male patient with oesophageal squamous-cell carcinoma was referred to us following the discovery of an area of high marker uptake following PET-TDM and corresponding to a pigmented skin lesion. No other areas of suspect high uptake were seen. The lesion was surgically excised and histological examination indicated seborrhoeic keratosis. The histological appearance was that of standard seborrhoeic keratosis without any notable mitotic activity. PET-TDM is an examination that enables diagnosis of malignancy. However, rare cases have been described of increased marker uptake by benign cutaneous tumours such as histiocytofibroma, pilomatricoma and condyloma. To date, there have only been only very few cases of increased uptake due to seborrhoeic keratosis. This extremely unusual case of increased glucose uptake in PET-TDM due to seborrhoeic keratosis confirms that the hypermetabolic activity detected by this examination is not necessarily synonymous with malignancy and that confirmation by clinical and histological findings is essential. The reasons for increased metabolic activity within such benign tumours are not known. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Correlation of hepatic {sup 18}F-fluorodeoxyglucose uptake with fatty liver

Energy Technology Data Exchange (ETDEWEB)

An, Young Sil; Yoon, Joon Kee; Hong, Seon Pyo; Joh, Chul Woo; Yoon, Seok Nam [Ajou University School of Medicine, Suwon (Korea, Republic of)

2006-10-15

Liver demonstrates heterogeneous FDG uptake and sometimes it shows abnormally increased uptake even though there is no malignant tissue. However, there was no previous study to correlate these various pattern of hepatic FDG uptake with benign liver disease. Therefore, we evaluated the significance of hepatic FDG uptake associated with various clinical factors including fatty liver, liver function tests and lipid profiles. We reviewed a total of 188 patients (male/female: 120/68, mean age: 50 {+-} 9) who underwent PET/CT for screening of malignancy. Patients with DM, impaired glucose tolerance, previous severe hepatic disease or long-term medication history were excluded. The FDG uptake in liver was analyzed semi-quantitatively using ROI on transaxial images (segment 8) and we compared mean standardized uptake value (SUV) between fatty liver and non-fatty liver group. We also evaluated the correlation between hepatic FDG uptake and various clinical factors including serum liver function test (ALT, AST), {gamma} -GT, total cholesterol and triglyceride concentration. The effect of alcoholic history and body mass index on hepatic FDG uptake was analyzed within the fatty liver patients. The hepatic FDG uptake of fatty liver group was significantly higher than that of non-fatty liver group. Serum total cholesterol and triglyceride concentration showed significant correlation with hepatic FDG uptake. However, there was no significant correlation between other factors (ALT, AST, and {gamma} -GT) and FDG uptake. Also there was no difference of mean SUV between normal and abnormal groups on the basis of alcoholic history and body mass index within fatty liver patients. Fatty liver and high serum triglyceride concentration were the independent factors affecting hepatic FDG uptake according to multivariate analysis. In conclusion, hepatic FDG uptake was strongly correlated with fatty liver and serum triglyceride concentration.

Uptake of cadmium from hydroponic solutions by willows ( Salix spp ...

African Journals Online (AJOL)

Salix integra 'Weishanhu') and Yizhibi (S. integra 'Yizhibi') were chosen as model plants to evaluate their potential for uptake of cadmium from hydroponic culture and relative uptake mechanism. Cadmium uptake showed a linear increase in the ...

Prognostic value of preoperative intratumoral FDG uptake heterogeneity in patients with epithelial ovarian cancer

Energy Technology Data Exchange (ETDEWEB)

Lee, Maria; Kim, Hee Seung; Chung, Hyun Hoon; Kim, Jae-Weon; Park, Noh-Hyun; Song, Yong Sang [Seoul National University College of Medicine, Department of Obstetrics and Gynecology, Cancer Research Institute, Seoul (Korea, Republic of); Lee, Hyunjong; Cheon, Gi Jeong [Seoul National University College of Medicine, Department of Nuclear Medicine, Cancer Research Institute, Seoul (Korea, Republic of)

2017-01-15

To investigate the prognostic value of intratumoral FDG uptake heterogeneity (IFH) derived from PET/CT in patients with epithelial ovarian cancer (EOC). We retrospectively reviewed patients with pathologically proven epithelial ovarian cancer who underwent preoperative {sup 18}F-FDG PET/CT scans. PET/CT parameters such as maximum and average standardized uptake values (SUV{sub max} and SUV{sub avg}), sum of all metabolic tumour volume (MTV), cumulative total lesion glycolysis (TLG) and IFH were assessed. Regression analyses were used to identify clinicopathological and imaging variables associated with disease-free survival (DFS). Clinicopathological data were reviewed for 61 eligible patients. The median duration of DFS was 13 months (range, 6-26 months), and 18 (29.5 %) patients experienced recurrence. High IFH values were associated with tumour recurrence (P = 0.005, hazard ratio 4.504, 95 % CI 1.572-12.902). The Kaplan-Meier survival graphs showed that DFS significantly differed in groups categorized based on IFH (P = 0.002, log-rank test). Moreover, there were significant differences in DFS (P = 0.009) and IFH (P = 0.040) between patients with and without recurrence. Preoperative IFH measured by {sup 18}F-FDG PET/CT was significantly associated with EOC recurrence. FDG-based heterogeneity could be a useful and potential predicator of EOC recurrence before treatment. (orig.)

Effects of Chemical Applications to Metal Polluted Soils on Cadmium Uptake by Rice Plant

Directory of Open Access Journals (Sweden)

Yoo J. H.

2013-04-01

Full Text Available Pot experiment using metal polluted soils was conducted to investigate the effects of lime, iron and sulfur on changes in Cd availability and uptake by rice plant. Drainage and irrigation of water were performed to develop redox changes like field cultivation. Iron chloride and sodium sulfate solutions were applied to the pots in the middle of growth period of rice plant. Reactive metal pool in heavily polluted soils was slightly decreased after treatments with lime, iron chloride, sodium sulfate and combination of these chemicals. However, cadmium uptake by rice plant was significantly different across the treatments and the extent of Cd pollution. For highly polluted soils, more Cd reduction was observed in iron chloride treatments. Cd content in polished rice for iron chloride and (iron chloride+organic matter treatments was only 16-23% and 25-37% compared to control and liming, respectively. Treatment of (iron chloride+sulfate rather increased Cd content in rice. For moderately polluted soils, Cd reduction rate was the order of (OM+iron chloride > iron chloride > lime. Other treatments including sulfate rather increased Cd content in rice maximum 3 times than control. It was proposed to determine the optimum application rate of iron for minimizing hazardous effect on rice plant.

Weighted Maximum-Clique Transversal Sets of Graphs

OpenAIRE

Chuan-Min Lee

2011-01-01

A maximum-clique transversal set of a graph G is a subset of vertices intersecting all maximum cliques of G. The maximum-clique transversal set problem is to find a maximum-clique transversal set of G of minimum cardinality. Motivated by the placement of transmitters for cellular telephones, Chang, Kloks, and Lee introduced the concept of maximum-clique transversal sets on graphs in 2001. In this paper, we study the weighted version of the maximum-clique transversal set problem for split grap...

Kinetics of phosphate uptake, growth, and accumulation of cyclic diphosphoglycerate in a phosphate-limited continuous culture of Methanobacterium thermoautotrophicum.

OpenAIRE

Krueger, R D; Harper, S H; Campbell, J W; Fahrney, D E

1986-01-01

The archaebacterium Methanobacterium thermoautotrophicum was grown in continuous culture at 65 degrees C in a phosphate-limited medium at specific growth rates from 0.06 to 0.28 h-1 (maximum growth rate [mu max] = 0.36 h-1). Cyclic-2,3-diphosphoglycerate (cyclic DPG) levels ranged from 2 to 20 mM in Pi-limited cells, compared with about 30 mM in batch-grown cells. The Monod constant for Pi-limited growth was 5 nM. Pi uptake rates were determined by following the disappearance of 32Pi from the...

Uptake of rare earth elements by dryopteris erythrosora (autumn fern)

International Nuclear Information System (INIS)

Ozaki, Takuo; Enomoto, Shuichi

2001-01-01

Mechanisms of uptake of rare earth elements (REEs) were investigated, particularly those by REE accumulator species (autumn fern). Rare earth elements are practically insoluble under natural conditions, suggesting some unknown mechanisms in REE accumulator species. In the present investigation, two notable phenomena were observed. (1) Concerning the ionic-radius dependence of REE uptake by leaves, nonaccumulator species showed an extremely high uptake for Y compared with the adjacent-ionic-radius REEs in the multitracer, while accumulator species showed no anomaly. (2) REE uptake by autumn fern was influenced by the addition of chelating chemical reagents in the uptake solution, while no effect was observed for nonaccumulator species. (author)

Maximum power demand cost

International Nuclear Information System (INIS)

Biondi, L.

1998-01-01

The charging for a service is a supplier's remuneration for the expenses incurred in providing it. There are currently two charges for electricity: consumption and maximum demand. While no problem arises about the former, the issue is more complicated for the latter and the analysis in this article tends to show that the annual charge for maximum demand arbitrarily discriminates among consumer groups, to the disadvantage of some [it

Influence of drugs on myocardial iodine-123 metaiodobenzylguanidine uptake in rabbit myocardium

Energy Technology Data Exchange (ETDEWEB)

Mayer, S.; Karanikas, G.; Rodrigues, M.; Sinzinger, H. [Dept. of Nuclear Medicine, University of Vienna (Austria)

2000-03-01

About 15 years ago, iodine-123 metaiodobenzylguanidine (MIBG) myocardial imaging was introduced for the evaluation of myocardial sympathetic nerve function. Two uptake mechanisms for MIBG have so far been identified: uptake type I, a saturable, energy-dependent mechanism, and uptake type II, a non-saturable, energy-independent mechanism. We incubated isolated rabbit myocardial tissue samples with{sup 123}I-MIBG in order to assess the uptake characteristics and the influence of varying incubation conditions. Furthermore, we examined the effects of several drugs and uptake inhibitors on the myocardial uptake of MIBG. The in vitro myocardial uptake of MIBG reached a steady plateau at 23.87%{+-}3.63% after 1 h, i.e. a concentration gradient of 10, in a thermo-independent manner within a concentration range from 1.5 to 1500 {mu}M. This indicates an unsaturable uptake process in the tested concentrations. Pre-incubation with the following drugs caused a significant inhibitory effect on myocardial MIBG uptake: haloperidol, levomepromazine, metoprolol, labetalol and clomipramine. According to our findings, the uptake mechanism seems to be an unspecific process, but the concentration gradient of 10 makes passive diffusion unlikely. Further studies with uptake-II-blocking substances as well as with isolated myocardial cells will be needed to clarify the nature of the myocardial MIBG uptake mechanism. (orig.)

Root distribution pattern and nitrogen uptake of some wheat and triticale germplasms in relation to rates and methods of nitrogen application

International Nuclear Information System (INIS)

Meena, N.L.; Seth, Jagdish

1975-01-01

A field experiment was conducted under irrigated conditions with four germplasms viz. Triticale(70-2), and wheat varieties HD 4502(durum), Kalyan Sona and Moti (aestivums) at the Indian Agricultural Research Institute Farm, New Delhi, during rabi season of 1972-73. The treatments comprised of three rates of nitrogen viz. 0,60 and 120 kg/ha and two methods of nitrogen application viz. (1) soil + foliar and (2) soil. The root distribution of the four germplasms, studied by 32 P injection technique was increased both vertically and horizontally with the addition of nitrogen. Root distribution of triticale was observed to be deep and spreading in habit, while durum proved to be shallow rooted and compact in nature. The total uptake of nitrogen was significantly increased with higher rates of nitrogen in all the germplasms. The maximum uptake of nitrogen was observed in the durum wheat. (author)

Actin-cytoskeleton rearrangement modulates proton-induced uptake

Energy Technology Data Exchange (ETDEWEB)

Ben-Dov, Nadav [Department of Physiology and Pharmacology, Faculty of Medicine, Tel-Aviv University, 69978 Tel-Aviv (Israel); Korenstein, Rafi, E-mail: korens@post.tau.ac.il [Department of Physiology and Pharmacology, Faculty of Medicine, Tel-Aviv University, 69978 Tel-Aviv (Israel)

2013-04-15

Recently it has been shown that elevating proton concentration at the cell surface stimulates the formation of membrane invaginations and vesicles accompanied by an enhanced uptake of macromolecules. While the initial induction of inward membrane curvature was rationalized in terms of proton-based increase of charge asymmetry across the membrane, the mechanisms underlying vesicle formation and its scission are still unknown. In light of the critical role of actin in vesicle formation during endocytosis, the present study addresses the involvement of cytoskeletal actin in proton-induced uptake (PIU). The uptake of dextran-FITC is used as a measure for the factual fraction of inward invaginations that undergo scission from the cell's plasma membrane. Our findings show that the rate of PIU in suspended cells is constant, whereas the rate of PIU in adherent cells is gradually increased in time, saturating at the level possessed by suspended cells. This is consistent with pH induced gradual degradation of stress-fibers in adherent cells. Wortmannin and calyculin-A are able to elevate PIU by 25% in adherent cells but not in suspended cells, while cytochalasin-D, rapamycin and latrunculin-A elevate PIU both in adherent and suspended cells. However, extensive actin depolymerization by high concentrations of latrunculin-A is able to inhibit PIU. We conclude that proton-induced membrane vesiculation is restricted by the actin structural resistance to the plasma membrane bending. Nevertheless, a certain degree of cortical actin restructuring is required for the completion of the scission process. - Highlights: ► Acidification of cells' exterior enhances uptake of macromolecules by the cells. ► Disruption of actin stress fibers leads to enhancement of proton induced uptake. ► Extensive depolymerization of cellular actin attenuates proton-induced uptake.

Uranium uptake by hydroponically cultivated crop plants

Energy Technology Data Exchange (ETDEWEB)

Soudek, Petr; Petrova, Sarka [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR, v.v.i. and Crop Research Institute, v.v.i., Rozvojova 263, 162 05 Prague 6 (Czech Republic); Benesova, Dagmar [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR, v.v.i. and Crop Research Institute, v.v.i., Rozvojova 263, 162 05 Prague 6 (Czech Republic); Faculty of Environment Technology, Institute of Chemical Technology, Technicka 5, 166 28 Prague 6 (Czech Republic); Dvorakova, Marcela [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR, v.v.i. and Crop Research Institute, v.v.i., Rozvojova 263, 162 05 Prague 6 (Czech Republic); Vanek, Tomas, E-mail: vanek@ueb.cas.cz [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR, v.v.i. and Crop Research Institute, v.v.i., Rozvojova 263, 162 05 Prague 6 (Czech Republic)

2011-06-15

Hydroponicaly cultivated plants were grown on medium containing uranium. The appropriate concentrations of uranium for the experiments were selected on the basis of a standard ecotoxicity test. The most sensitive plant species was determined to be Lactuca sativa with an EC{sub 50} value about 0.1 mM. Cucumis sativa represented the most resistant plant to uranium (EC{sub 50} = 0.71 mM). Therefore, we used the uranium in a concentration range from 0.1 to 1 mM. Twenty different plant species were tested in hydroponic solution supplemented by 0.1 mM or 0.5 mM uranium concentration. The uranium accumulation of these plants varied from 0.16 mg/g DW to 0.011 mg/g DW. The highest uranium uptake was determined for Zea mays and the lowest for Arabidopsis thaliana. The amount of accumulated uranium was strongly influenced by uranium concentration in the cultivation medium. Autoradiography showed that uranium is mainly localized in the root system of the plants tested. Additional experiments demonstrated the possibility of influencing the uranium uptake from the cultivation medium by amendments. Tartaric acid was able to increase uranium uptake by Brassica oleracea and Sinapis alba up to 2.8 times or 1.9 times, respectively. Phosphate deficiency increased uranium uptake up to 4.5 times or 3.9 times, respectively, by Brassica oleracea and S. alba. In the case of deficiency of iron or presence of cadmium ions we did not find any increase in uranium accumulation. - Highlights: > The uranium accumulation in twenty different plant species varied from 0.160 to 0.011 mg/g DW. > Uranium is mainly localized in the root system. > Tartaric acid was able to increase uranium uptake by Brassica oleracea and Sinapis alba. > The phosphates deficiency increase the uranium uptake.

Uranium uptake by hydroponically cultivated crop plants

International Nuclear Information System (INIS)

Soudek, Petr; Petrova, Sarka; Benesova, Dagmar; Dvorakova, Marcela; Vanek, Tomas

2011-01-01

Hydroponicaly cultivated plants were grown on medium containing uranium. The appropriate concentrations of uranium for the experiments were selected on the basis of a standard ecotoxicity test. The most sensitive plant species was determined to be Lactuca sativa with an EC 50 value about 0.1 mM. Cucumis sativa represented the most resistant plant to uranium (EC 50 = 0.71 mM). Therefore, we used the uranium in a concentration range from 0.1 to 1 mM. Twenty different plant species were tested in hydroponic solution supplemented by 0.1 mM or 0.5 mM uranium concentration. The uranium accumulation of these plants varied from 0.16 mg/g DW to 0.011 mg/g DW. The highest uranium uptake was determined for Zea mays and the lowest for Arabidopsis thaliana. The amount of accumulated uranium was strongly influenced by uranium concentration in the cultivation medium. Autoradiography showed that uranium is mainly localized in the root system of the plants tested. Additional experiments demonstrated the possibility of influencing the uranium uptake from the cultivation medium by amendments. Tartaric acid was able to increase uranium uptake by Brassica oleracea and Sinapis alba up to 2.8 times or 1.9 times, respectively. Phosphate deficiency increased uranium uptake up to 4.5 times or 3.9 times, respectively, by Brassica oleracea and S. alba. In the case of deficiency of iron or presence of cadmium ions we did not find any increase in uranium accumulation. - Highlights: → The uranium accumulation in twenty different plant species varied from 0.160 to 0.011 mg/g DW. → Uranium is mainly localized in the root system. → Tartaric acid was able to increase uranium uptake by Brassica oleracea and Sinapis alba. → The phosphates deficiency increase the uranium uptake.

Nitrogen uptake kinetics of freshly isolated zooxanthellae

Digital Repository Service at National Institute of Oceanography (India)

Wafar, M.V.M.; Wafar, S.; Rajkumar, R.

that for nitrate [2.8 nmol. ( mu chl-a)./1h/1] and urea [0.37 nmol. ( mu chl-a)./1h/1]. Half-saturation constants for uptake of the three nitrogen compounds were in the range of 10-15 mu mol.l/1. Generally, uptake of any one nitrogen substrate appears to be inhibit...

The Test of Inaccurate Position of Renography Detector to Relative UptakeFigure and Individual Excretion

International Nuclear Information System (INIS)

Bambang-Supardiyono; Prayitno

2000-01-01

Accuracy of detector position toward the kidney location (preciseposition) in renography will resulting the maximum count figure, detectorposition change from the precise point (inaccurate) will decreasing the countrate. Therefore for it had been simulated the influence of count figure ofright kidney (fixed left kidney count) ± 5 % to ± 20 % to relativeuptake figure and individual excretion. Based on the calculation it was foundthat the relation of detector position ± 0.5 cm to ± 2 cm from theprecise point will have effect to relative uptake figure ± (1.25 % to 5.00%), the fixed individual excretion figure. The change is still can beaccepted because the qualitative information with 10 % accuracy is stillacceptable. (author)

Uptake of carnitine by red blood cells

International Nuclear Information System (INIS)

Campa, M.; Borum, P.

1986-01-01

A significant amount of blood carnitine (70% of cord blood and 40% of blood from healthy adults) is partitioned into the red blood cell compartment of whole blood. Data indicate that the plasma compartment and the red blood cell compartment of whole blood represent different metabolic pools of carnitine. There are no data to indicate that red blood cells synthesize carnitine, but our understanding of the uptake of carnitine by red blood cells is negligible. Red blood cells were obtained from healthy adults, washed twice with normal saline, and used for uptake experiments. When the cells were incubated at 37 0 C in the presence of 14 C-carnitine, radioactivity was found both in the soluble cytosolic and membrane fractions of the cells following lysis. The uptake was dependent upon the time of incubation, temperature of incubation, and carnitine concentration in the incubation medium. Washed red blood cell membranes incubated with 14 C-carnitine showed specific binding of radioactivity. These data are consistent with the hypothesis that red blood cells have an uptake mechanism for L-carnitine

Effect of counting system dead time on thyroid uptake measurements

International Nuclear Information System (INIS)

Simpkin, D.J.

1984-01-01

Equations are derived and the results of numerical calculations shown that illustrate the effect of counting system dead time on measured thyroid uptake of radioiodine. It is predicted that the observed uptake is higher than the true uptake due to system dead time. This is shown for both paralyzing and nonparalyzing dead time. The effect of increasing the administered activity is shown to increase the measured uptake, in a manner predicted by the paralyzable and nonparalyzable dead time models

Radiocolloid Uptake in the Pancreas Islet Cell Tumor: Case Report

Energy Technology Data Exchange (ETDEWEB)

Yang, W. J.; Chung, S. K.; Yeon, S. K.; Shinn, K. S.; Bahk, Y. W. [Catholic University College of Medicine, Seoul (Korea, Republic of)

1994-03-15

Colloid uptake in various hepatic conditions such as focal nodular hyperplasia, regenerating nodular in the cirrhotic liver, hamartoma, hemangioma and rarely hepatoma has been documented. Extrahepatic tumors may show colloid uptake and they include splenic hemangioma, malignant fibrous histiocytoma, breast carcinoma and Kaposi's sarcoma. The mechanism of colloid uptake in those lesions is associated with phagocytic activity in or around the tumors. We report a pancreas islet cell tumor that showed colloid uptake on {sup 99m}Tc-phytate liver scan without histologic evidence of phagocytosis by tumor cells or infiltration of phagocytes in the tumor. Microscopically the tumor was highly vascular and showed diffuse hemorrhage throughout the tumor. We postulated that extravasation of the colloid into the tumor interstitium caused nonspecific colloid uptake in this tumor. It is expected that hemorrhagic tumor may show nonspecific colloid uptake without phagocytosis in or about the lesion.

Radiocolloid Uptake in the Pancreas Islet Cell Tumor: Case Report

International Nuclear Information System (INIS)

Yang, W. J.; Chung, S. K.; Yeon, S. K.; Shinn, K. S.; Bahk, Y. W.

1994-01-01

Colloid uptake in various hepatic conditions such as focal nodular hyperplasia, regenerating nodular in the cirrhotic liver, hamartoma, hemangioma and rarely hepatoma has been documented. Extrahepatic tumors may show colloid uptake and they include splenic hemangioma, malignant fibrous histiocytoma, breast carcinoma and Kaposi's sarcoma. The mechanism of colloid uptake in those lesions is associated with phagocytic activity in or around the tumors. We report a pancreas islet cell tumor that showed colloid uptake on 99m Tc-phytate liver scan without histologic evidence of phagocytosis by tumor cells or infiltration of phagocytes in the tumor. Microscopically the tumor was highly vascular and showed diffuse hemorrhage throughout the tumor. We postulated that extravasation of the colloid into the tumor interstitium caused nonspecific colloid uptake in this tumor. It is expected that hemorrhagic tumor may show nonspecific colloid uptake without phagocytosis in or about the lesion.

Mechanism of Uptake of Trace Elements by Plants

International Nuclear Information System (INIS)

Broda, E.

1965-01-01

MECHANISM OF UPTAKE OF TRACE ELEMENTS BY PLANTS (EXPERIMENTS WlTH RADIOZINC). Some authors have assumed that the uptake of (essential or non-essential) trace elements by plants is due to active transport, and therefore needs metabolic energy. In our laboratory it has been found that the uptake of zinc (“6”5Zn) by chlorella and barley roots is, in the main, a passive process, and is based largely on ion exchange. In these experiments the Zn system contrasted sharply with actively transporting systems, e. g. the K system, although the extent of accumulation may be similar: (1) decouplers (DNP, azide) or anaerobiosis do not depress the uptake of Zn: (2) plants killed by grinding, freezing or alcohol treatment take up more Zn than living plants: (3) the temperature coefficient of the Zn uptake is small: (4) many ions compete with Zn, i.e. the uptake is unspecific. We have measured - primarily with dead cells, where equilibria are reached easily - the competition of several foreign ions with radiozinc at fixed pH (usually 6). These values have been compared with analogous values obtained with radiozinc (and verified with radiocopper) in respect to cation exchange resins. It is concluded from the sequence of the different ions that the active sites in the cells are mainly carboxyl groups. Probably most of the ‘exchanger’ consists of carbohydrate derivatives in the cell wall, i.e. in the ‘free space’, However, both by Langmuir analysis of the observed ‘uptake isotherm’ and by radiochemical work with partly blocked material, sites with anomalous affinity to Zn have been demonstrated. These may be imidazol groups in the proteins known to bind zinc strongly by complexation. (author)

Tumor grade-related thallium-201 uptake in chondrosarcomas

International Nuclear Information System (INIS)

Kaya, G.C.; Demir, Y.; Ozkal, S.

2010-01-01

Diagnosis of low-grade chondrosarcoma, especially discrimination between enchondroma and low-grade chondrosarcoma, may be difficult pathologically. The aim of this study was to evaluate the value of thallium-201 (Tl-201) scintigraphy in the diagnosis of chondrosarcoma and to investigate whether there was a correlation between Tl-201 uptake and tumor grade. We retrospectively evaluated 121 patients with pathologically proven bone and soft tissue tumors diagnosed between the years 1999 and 2007. All patients were followed by the Bone and Soft Tissue Tumor Working Group in our hospital. Twenty-three patients, mean age 44±15 (range 17-72) years, with a diagnosis of cartilaginous tumors were included. Increased Tl-201 uptake at the lesion sites greater than background was evaluated as malignant tumor. For the pathologic classification, a grading system (grade 1-3) based on the histopathologic findings was used. Pearson correlation coefficient was used to determine whether there was any correlation between Tl-201 uptake and tumor grade in chondrosarcoma. There were 7 enchondromas and 16 chondrosarcomas. Four of 16 patients with chondrosarcoma had lesions pathologically classified as grade 3, 5 as grade 2, and 7 had grade 1 chondrosarcoma. Increased Tl-201 uptake was observed in all patients with grade 3 chondrosarcoma and 2 patients with grade 2 chondrosarcoma. Of 10 patients with chondrosarcoma, 3 grade 2 chondrosarcomas and 7 grade 1 chondrosarcomas, there was no Tl-201 uptake in the tumor region. A significant correlation was found between Tl-201 uptake and tumor grade in chondrosarcoma (p=0.002, r=0.71). Only a few reports in literature have demonstrated false negative results in low-grade chondrosarcoma. Tl-201 uptake was related to tumor grade in chondrosarcoma. If there is a possibility of chondrosarcoma, Tl-201 scintigraphy should be reported with caution. (author)

Manganese uptake and interactions with cadmium in the hyperaccumulator-Phytolacca Americana L

Energy Technology Data Exchange (ETDEWEB)

Peng Kejian [College of Life Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Hunan Research Academy of Environmental Sciences Changsha 410004 (China); Luo Chunling [Department of Civil and Structural Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong); You Wuxin [College of Life Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Lian Chunlan [Asian Natural Environmental Science Center, University of Tokyo, 1-1-8 Midori-cho, Nishitokyo, Tokyo 188-0002 (Japan); Li Xiangdong [Department of Civil and Structural Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong); Shen Zhenguo [College of Life Sciences, Nanjing Agricultural University, Nanjing 210095 (China)], E-mail: zgshen@njau.edu.cn

2008-06-15

In the present study, the accumulation of Mn and other metals by Phytolacca Americana L. from contaminated soils in Hunan Province, South China, was investigated. Results showed that the average concentrations of Mn in the leaves and roots reached 2198 and 80.4 mg kg{sup -1} (dry weight), respectively, with a maximum 13,400 mg kg{sup -1} in the leaves. A significant correlation was found between Mn concentrations in the plant leaves and those in the corresponding soils. Hydroponic experiments were also conducted to study the Cd uptake ability and interactions between Mn and Cd in the plant. It was found that P. americana hyperaccumulated not only Mn, but also Cd in the leaves. In the presence of Cd, adding Mn to the solution significantly improved the plant growth and reduced the concentrations of Cd in all organs of the plant.

Decreased cisplatin uptake by resistant L1210 leukemia cells

International Nuclear Information System (INIS)

Hromas, R.A.; North, J.A.; Burns, C.P.

1987-01-01

Cisplatin resistance remains poorly understood compared to other forms of anti-neoplastic drug resistance. In this report radiolabelled cisplatin and rapid separation techniques were used to compare drug uptake by L1210 leukemia cells that are sensitive (K25) or resistant (SCR9) to cisplatin. Uptake of cisplatin by both cell lines was linear without saturation kinetics up to 100 μM. The resistant ZCR9 cells had 36-60% reduced drug uptake as compared to its sensitive parent line, K25. In contrast, there was no difference in the rate of efflux. We conclude that a decreased rate of uptake is one possible mechanism of cellular cisplatin resistance. (Author)

The effect of hydrate promoters on gas uptake.

Science.gov (United States)

Xu, Chun-Gang; Yu, Yi-Song; Ding, Ya-Long; Cai, Jing; Li, Xiao-Sen

2017-08-16

Gas hydrate technology is considered as a promising technology in the fields of gas storage and transportation, gas separation and purification, seawater desalination, and phase-change thermal energy storage. However, to date, the technology is still not commercially used mainly due to the low gas hydrate formation rate and the low gas uptake. In this study, the effect of hydrate promoters on gas uptake was systematically studied and analyzed based on hydrate-based CH 4 storage and CO 2 capture from CO 2 /H 2 gas mixture experiments. Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR) and gas chromatography (GC) were employed to analyze the microstructures and gas compositions. The results indicate that the effect of the hydrate promoter on the gas uptake depends on the physical and chemical properties of the promoter and gas. A strong polar ionic promoter is not helpful towards obtaining the ideal gas uptake because a dense hydrate layer is easily formed at the gas-liquid interface, which hinders gas diffusion from the gas phase to the bulk solution. For a weak polar or non-polar promoter, the gas uptake depends on the dissolution characteristics among the different substances in the system. The lower the mutual solubility among the substances co-existing in the system, the higher the independence among the substances in the system; this is so that each phase has an equal chance to occupy the hydrate cages without or with small interactions, finally leading to a relatively high gas uptake.

Calibration of a Plant Uptake Model with Plant- and Site-Specific. Data for Uptake of Chlorinated Organic Compounds into Radish

DEFF Research Database (Denmark)

Trapp, Stefan

2015-01-01

The uptake of organic pollutants by plants is an important process for the exposure of humans to toxic chemicals. The objective of this study was to calibrate the parameters of a common plant uptake model by comparison to experimental results from literature. Radish was grown in contaminated soil...... with default data and site-specific data were similar. Deposition from air was the major uptake mechanism into shoots. Transport from soil with resuspended particles was only relevant for the contaminated plot. The calculation results (in dry weight) were most sensitive to changes of the water content of plant...

Atmospheric Direct Uptake and Long-term Fate of Radiocesium in Trees after the Fukushima Nuclear Accident

Science.gov (United States)

Mahara, Yasunori; Ohta, Tomoko; Ogawa, Hideki; Kumata, Atsushi

2014-11-01

Large areas of forests were radioactively contaminated by the Fukushima nuclear accident of 2011, and forest decontamination is now an important problem in Japan. However, whether trees absorb radioactive fallout from soil via the roots or directly from the atmosphere through the bark and leaves is unclear. We measured the uptake of radiocesium by trees in forests heavily contaminated by the Fukushima nuclear accident. The radiocesium concentrations in sapwood of two tree species, the deciduous broadleaved konara (Quercus serrata) and the evergreen coniferous sugi (Cryptomeria japonica), were higher than that in heartwood. The concentration profiles showed anomalous directionality in konara and non-directionality in sugi, indicating that most radiocesium in the tree rings was directly absorbed from the atmosphere via bark and leaves rather than via roots. Numerical modelling shows that the maximum 137Cs concentration in the xylem of konara will be achieved 28 years after the accident. Conversely, the values for sugi will monotonously decrease because of the small transfer factor in this species. Overall, xylem 137Cs concentrations will not be affected by root uptake if active root systems occur 10 cm below the soil.

Automatic measurement of the radioactive mercury uptake by the kidney

International Nuclear Information System (INIS)

Zurowski, S.; Raynaud, C.; CEA, 91 - Orsay

1976-01-01

An entirely automatic method to measure the Hg uptake by the kidney is proposed. The following operations are carried out in succession: measurement of extrarenal activity, demarcation of uptake areas, anatomical identification of uptake areas, separation of overlapping organ images and measurement of kidney depth. The first results thus calculated on 30 patients are very close to those obtained with a standard manual method and are highly encouraging. Two important points should be stressed: a broad demarcation of the uptake areas is necessary and an original method, that of standard errors, is useful for the background noise determination and uptake area demarcation. This automatic measurement technique is so designed that it can be applied to other special cases [fr

Cardiovascular responses during orthostasis - Effect of an increase in maximal O2 uptake

Science.gov (United States)

Convertino, V. A.; Montgomery, L. D.; Greenleaf, J. E.

1984-01-01

A study is described which tests the hypothesis that changes in aerobic activity (increases in maximum oxygen uptake) will reduce the effectiveness of cardiovascular reflexes to regulate blood pressure during orthostasis. The hypothesis was tested by measuring heart rate, blood pressure and blood volume responses in eight healthy male subjects before and after an eight-day endurance regimen. The results of the study suggest that the physiologic responses to orthostasis are dependent upon the rate of plasma volume loss and pooling, and are associated with training-induced hypervolemia. It is indicated that endurance type exercise training enhances cardiovascular adjustments during tilt. The implications of these results for the use of exercise training as a countermeasure and/or therapeutic method for the prevention of cardiovascular instability during orthostatic stress are discussed.

Effect of nutrition peculiarities on 137Cs uptake

International Nuclear Information System (INIS)

Knizhnikov, V.A.; Marej, A.N.; Borisov, B.K.; Petukhova, Eh.V.

1980-01-01

Reasons for different 137 Cs uptake from diets of the vegetable-animal type are studied. Indexes of accumulation multiplicity for Moscow and the Byelorussian-Ukrainian wooded district are compared. 137 Cs buildup levels in the organism of the USSR and the USA population are presented. The most probable reason for peculiarities in 137 Cs uptake from various types of diet, as well as the reason for the alterations in the uptake of this radionuclide from the diet of the same type, is the non-uniformity of 137 Cs contribution of aerial and nonaerial origin

Effects of salt stress on phosphorus uptake by european rape sheiaralle

International Nuclear Information System (INIS)

Li Guihua; Zhang Jianfeng; Wei Dongpu; Yang Juncheng; Mei Yong

2007-01-01

The effects of different salinity on phosphorus uptake by European rape Sheiaralle were studied under hydroponics and sand culture conditions. The results showed that above ground uptake of instant P increased with the salinity increased, the uptake of 32 P by roots firstly decreased and then increased with the increase salinity. Instant P uptake by Brassica napus was lower under different salinity treatment than in non-saline condition (P - , but the biomass yield decreased much faster than P uptake, so P relatively condensed, and uptake of P by Brassica napus increased as the salinity (including non-saline treatment) was increased (P<0.05). Fresh weight of Brassica napus decreased significantly with the salinity increased (P<0.05). (authors)

Thyroid Scan and Uptake

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Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Thyroid Scan and Uptake ...

Multiple pathways for uptake of paraquat, methylglyoxal bis(guanylhydrazone), and polyamines

Energy Technology Data Exchange (ETDEWEB)

Byers, T.L.; Kameji, R.; Rannels, D.E.; Pegg, A.E.

1987-06-01

The uptake of polyamines, methylglyoxal bis(guanylhydrazone) (MGBG), and paraquat (N,N-dimethyl-4,4'-bipyridylium) into control Chinese hamster ovary (CHO) cells and a mutant CHO cell line selected for resistance to the toxicity of MGBG was examined. In contrast to control CHO cells, the mutant cells had no detectable uptake of (/sup 14/C)-MGBG or any of the polyamines. There was no difference between the two cell lines in the uptake of ..cap alpha..-aminoisobutyric (/sup 3/H-AIB), which indicates that there was no general change in membrane transport processes. The mutant cells were also found to be resistant to the toxicity of paraquat and to have a reduced capability to take up the herbicide. This finding confirms that the uptake of paraquat is necessary for the toxicity of this compound and that the paraquat is taken up by a transport system that also transports MGBG. Competition experiments showed that an excess of unlabeled paraquat inhibited uptake of MGBG and, to a lesser extent, uptake of putrescine and spermidine, but no inhibitory action on spermine uptake could be detected. Studies with type II cells isolated from rat lung also demonstrated uptake of paraquat and spermidine, but paraquat was only a weak inhibitor of spermidine uptake in this system. These results suggest that there may be multiple systems for the uptake of MGBG and polyamines and that paraquat is taken up by at least one but not by all of these systems.

Multiple pathways for uptake of paraquat, methylglyoxal bis(guanylhydrazone), and polyamines

International Nuclear Information System (INIS)

Byers, T.L.; Kameji, R.; Rannels, D.E.; Pegg, A.E.

1987-01-01

The uptake of polyamines, methylglyoxal bis(guanylhydrazone) (MGBG), and paraquat [N,N-dimethyl-4,4'-bipyridylium] into control Chinese hamster ovary (CHO) cells and a mutant CHO cell line selected for resistance to the toxicity of MGBG was examined. In contrast to control CHO cells, the mutant cells had no detectable uptake of [ 14 C]-MGBG or any of the polyamines. There was no difference between the two cell lines in the uptake of α-aminoisobutyric ( 3 H-AIB), which indicates that there was no general change in membrane transport processes. The mutant cells were also found to be resistant to the toxicity of paraquat and to have a reduced capability to take up the herbicide. This finding confirms that the uptake of paraquat is necessary for the toxicity of this compound and that the paraquat is taken up by a transport system that also transports MGBG. Competition experiments showed that an excess of unlabeled paraquat inhibited uptake of MGBG and, to a lesser extent, uptake of putrescine and spermidine, but no inhibitory action on spermine uptake could be detected. Studies with type II cells isolated from rat lung also demonstrated uptake of paraquat and spermidine, but paraquat was only a weak inhibitor of spermidine uptake in this system. These results suggest that there may be multiple systems for the uptake of MGBG and polyamines and that paraquat is taken up by at least one but not by all of these systems

Uptake and depuration of 131I by the edible periwinkle Littorina littorea: uptake from labelled seaweed (Chondrus crispus)

International Nuclear Information System (INIS)

Wilson, R.C.; Vives i Batlle, J.; McDonald, P.; Parker, T.G.

2005-01-01

Uptake and depuration experiments of 131 I from labelled seaweed (Chondrus crispus) by the edible periwinkle Littorina littorea have been performed. Radioiodine concentrations in winkles during uptake followed first-order kinetics with an uptake half-time of 1 day, and a calculated equilibrium concentration (C ∞ ) of 21 000 Bq kg -1 resulting in a transfer factor of 0.07 with respect to the labelled seaweed used as food. For depuration, a biphasic sequence with biological half-lives of 1 and 24 days was determined. The results suggest that in general, iodine turnover in periwinkles is slower than observed for other molluscs (monophasic biological half-lives in the order of 2-3 days). Both environmental media, food and seawater, can be significant sources of radioiodine for the winkle

Inter-taxa differences in root uptake of 103/106Ru by plants

International Nuclear Information System (INIS)

Willey, N.J.; Fawcett, K.

2006-01-01

Ruthenium-106 is of potential radioecological importance but soil-to-plant Transfer Factors for it are available only for few plant species. A Residual Maximum Likelihood (REML) procedure was used to construct a database of relative 103/106 Ru concentrations in 114 species of flowering plants including 106 species from experiments and 12 species from the literature (with 4 species in both). An Analysis of Variance (ANOVA), coded using a recent phylogeny for flowering plants, was used to identify a significant phylogenetic effect on relative mean 103/106 Ru concentrations in flowering plants. There were differences of 2465-fold in the concentration to which plant species took up 103/106 Ru. Thirty-nine percent of the variance in inter-species differences could be ascribed to the taxonomic level of Order or above. Plants in the Orders Geraniales and Asterales had notably high uptake of 103/106 Ru compared to other plant groups. Plants on the Commelinoid monocot clades, and especially the Poaceae, had notably low uptake of 103/106 Ru. These data demonstrate that plant species are not independent units for 103/106 Ru concentrations but are linked through phylogeny. It is concluded that models of soil-to-plant transfer of 103/106 Ru should assume that; neither soil variables alone affect transfer nor plant species are independent units, and taking account of plant phylogeny might aid predictions of soil-to-plant transfer of 103/106 Ru, especially for species for which Transfer Factors are not available

Thyroid Scan and Uptake

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Full Text Available ... A thyroid scan is a type of nuclear medicine imaging. The radioactive iodine uptake test (RAIU) is ... thyroid function, but does not involve imaging. Nuclear medicine is a branch of medical imaging that uses ...

Thyroid Scan and Uptake

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Full Text Available ... which are encased in metal and plastic and most often shaped like a box, attached to a ... will I experience during and after the procedure? Most thyroid scan and thyroid uptake procedures are painless. ...

Thyroid Scan and Uptake

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Full Text Available ... Actual scanning time for each thyroid uptake is five minutes or less. top of page What will ... diagnostic procedures have been used for more than five decades, and there are no known long-term ...

Thyroid Scan and Uptake

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Full Text Available ... Because nuclear medicine procedures are able to pinpoint molecular activity within the body, they offer the potential ... or imaging device that produces pictures and provides molecular information. The thyroid scan and thyroid uptake provide ...

Thyroid Scan and Uptake

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Full Text Available ... of page What will I experience during and after the procedure? Most thyroid scan and thyroid uptake ... you otherwise, you may resume your normal activities after your nuclear medicine scan. If any special instructions ...

Thyroid Scan and Uptake

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Full Text Available ... for several hours before your exam because eating can affect the accuracy of the uptake measurement. Jewelry ... small hand-held device resembling a microphone that can detect and measure the amount of the radiotracer ...

Thyroid Scan and Uptake

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Full Text Available ... scan and thyroid uptake provide information about the structure and function of the thyroid. The thyroid is ... computer, create pictures offering details on both the structure and function of organs and tissues in your ...

Thyroid Scan and Uptake

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Full Text Available ... eat for several hours before your exam because eating can affect the accuracy of the uptake measurement. ... often unattainable using other imaging procedures. For many diseases, nuclear medicine scans yield the most useful information ...

Thyroid Scan and Uptake

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Full Text Available ... When radiotracer is taken by mouth, in either liquid or capsule form, it is typically swallowed up ... radioactive iodine (I-123 or I-131) in liquid or capsule form to swallow. The thyroid uptake ...

Thyroid Scan and Uptake

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Full Text Available ... eat for several hours before your exam because eating can affect the accuracy of the uptake measurement. ... its radioactivity over time. It may also pass out of your body through your urine or stool ...

Thyroid Scan and Uptake

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Full Text Available ... procedures within the last two months that used iodine-based contrast material. Your doctor will instruct you ... a type of nuclear medicine imaging. The radioactive iodine uptake test (RAIU) is also known as a ...

Quantification of radionuclide uptake levels for primary bone tumors

Directory of Open Access Journals (Sweden)

Hasford Francis

2015-04-01

Full Text Available The purpose of the study is to quantify the level of uptake of administered radionuclide in primary bone tumors for patients undergoing bone scintigraphy. Retrospective study on 48 patient's scintigrams to quantify the uptake levels of administered radiopharmaceuticals was performed in a nuclear medicine unit in Ghana. Patients were administered with activity ranging between 0.555 and 1.110 MBq (15–30 mCi, and scanned on Siemens e.cam SPECT system. Analyses on scintigrams were performed with Image J software by drawing regions of interest (ROIs over identified hot spots (pathologic sites. Nine skeletal parts namely cranium, neck, shoulder, sacrum, sternum, vertebra, femur, ribcage, and knee were considered in the study, which involved 96 identified primary tumors. Radionuclide uptakes were quantified in terms of the estimated counts of activity per patient for identified tumor sites. Average normalized counts of activity (nGMC per patient ranged from 5.2759 ± 0.6590 cts/mm2/MBq in the case of cranium tumors to 72.7569 ± 17.8786 cts/mm2/MBq in the case of ribcage tumors. The differences in uptake levels could be attributed to different mechanisms of Tc-99m MDP uptake in different types of bones, which is directly related to blood flow and degree of osteoblastic activity. The overall normalized count of activity for the 96 identified tumors was estimated to be 23.0350 ± 19.5424 cts/mm2/MBq. The study revealed highest uptake of activity in ribcage and least uptake in cranium. Quantification of radionuclide uptakes in tumors is important and recommended in assessing patient's response to therapy, doses to critical organs and in diagnosing tumors.

The MDP skull uptake test: A new diagnostic tool

International Nuclear Information System (INIS)

Ell, P.J.; Jarritt, P.H.; Cullum, I.; Lui, D.

1984-01-01

An original approach to the measurement of bone turnover is presented. With SPECT, the authors have measured in pgr/ml, the uptake of MDP by the skull in man. The Cleon 710 scanner, ring phantoms and bone biopsies were used for ultimate in vivo/in vitro count recovery correlation and calibration. A normal range for 24 patients was found: 8.5 to 19.5 pgr/ml with a mean of 14. For patients with bony metastases (12), the values were: 22.5 to 50, mean of 30. For 5 patients with osteomalacia, the values were 46 to 68, mean of 62: for 12 patients with hyperparathyroidism, the values were 37 to 48.5, mean of 43. In 3 patients with Pagets disease, the values were 58.5 to 75, with a mean of 65. In 76 patients with metastatic disease to bone, the conventional wholebody bone scan was investigated against the following: 24h wholebody retention of MDP (WBR), skull uptake as described and GFR by Cr-51-DTPA. There is a correlation between GFR and WBR - r=0.67. There is a lesser correlation between GFR and skull uptake - r=0.3. There is no correlation between skull uptake and WBR - r=0.1. The comparison of skull uptake data with normal whole body bone scans leads to a significant proportion of cancer patients with positive skull uptake data. Monostotic disease (especially if metabolic in nature) expresses itself by abnormal skull uptake even if the clinical site of abnormality lies outside the skull. This new technique is ideal as a tool to investigate phosphonate concentration in bone. With it, the authors have shown the effect of specific activity of label on skull uptake, which increases as the specific activity of labelled MDP decreases

Prognostic implication of the metastatic lesion-to-ovarian cancer standardised uptake value ratio in advanced serous epithelial ovarian cancer

International Nuclear Information System (INIS)

Chung, Hyun Hoon; Lee, Maria; Kim, Hee-Seung; Kim, Jae-Weon; Park, Noh-Hyun; Song, Yong Sang; Cheon, Gi Jeong

2017-01-01

To evaluate the prognostic value of metabolic activity of metastatic lesions measured by 18 F-flurodeoxyglucose ( 18 F-FDG) uptake on preoperative positron emission tomography/computed tomography (PET/CT) in patients with advanced serous epithelial ovarian cancer (EOC). Clinico-pathological variables and PET/CT parameters such as the maximum standardised uptake value of the ovarian cancer (SUV ovary ), metastatic lesions (SUV meta ), and the metastatic lesion-to-ovarian cancer standardised uptake value ratio (SUV meta /SUV ovary ) were assessed in International Federation of Gynaecology and Obstetrics (FIGO) stage III, IV patients. Clinico-pathological data were retrospectively reviewed for 94 eligible patients. The median progression-free survival (PFS) was 18.5 months (range, 6-90 months), and 57 (60.6%) patients experienced recurrence. Older age [P = 0.017, hazard ratio (HR) 1.036, 95% CI 1.006-1.066], residual disease after surgery (P = 0.024, HR 1.907, 95% CI 1.087-3.346), and high SUV meta /SUV ovary (P = 0.019, HR 2.321, 95% CI 1.148-4.692) were independent risk factors of recurrence. Patients with high SUV meta /SUV ovary showed a significantly worse PFS than those with low SUV meta /SUV ovary (P = 0.007, log-rank test). Preoperative SUV meta /SUV ovary was significantly associated with recurrence and has an incremental prognostic value for PFS in patients with advanced serous EOC. (orig.)

Silicate reduces cadmium uptake into cells of wheat

International Nuclear Information System (INIS)

Greger, Maria; Kabir, Ahmad H.; Landberg, Tommy; Maity, Pooja J.; Lindberg, Sylvia

2016-01-01

Cadmium (Cd) is a health threat all over the world and high Cd content in wheat causes high Cd intake. Silicon (Si) decreases cadmium content in wheat grains and shoot. This work investigates whether and how silicate (Si) influences cadmium (Cd) uptake at the cellular level in wheat. Wheat seedlings were grown in the presence or absence of Si with or without Cd. Cadmium, Si, and iron (Fe) accumulation in roots and shoots was analysed. Leaf protoplasts from plants grown without Cd were investigated for Cd uptake in the presence or absence of Si using the fluorescent dye, Leadmium Green AM. Roots and shoots of plants subjected to all four treatments were investigated regarding the expression of genes involved in the Cd uptake across the plasma membrane (i.e. LCT1) and efflux of Cd into apoplasm or vacuole from the cytosol (i.e. HMA2). In addition, phytochelatin (PC) content and PC gene (PCS1) expression were analysed. Expression of iron and metal transporter genes (IRT1 and NRAMP1) were also analysed. Results indicated that Si reduced Cd accumulation in plants, especially in shoot. Si reduced Cd transport into the cytoplasm when Si was added both directly during the uptake measurements and to the growth medium. Silicate downregulated LCT1 and HMA2 and upregulated PCS1. In addition, Si enhanced PC formation when Cd was present. The IRT1 gene, which was downregulated by Cd was upregulated by Si in root and shoot facilitating Fe transport in wheat. NRAMP1 was similarly expressed, though the effect was limited to roots. This work is the first to show how Si influences Cd uptake on the cellular level. - Highlights: • Si decreases accumulation and translocation of Cd in plants at tissue level. • This work is the first to show how Si influences Cd uptake. • Si decreases Cd uptake into cell and downregulates heavy metal transporter LCT1. • Si downregulates HMA2 transporter, which regulates Cd transport from root to shoot. • Si increases phytochelatin formation

Water uptake by salts during the electrolyte processing for thermal batteries

Science.gov (United States)

Masset, Patrick; Poinso, Jean-Yves; Poignet, Jean-Claude

Water uptake of single salts and electrolytes were measured in industrial conditions (dry-room). The water uptake rate ϑ (g h -1 cm -2) was expressed with respect to the apparent area of contact of the salt with atmosphere of the dry room. The water uptake by potassium-based salts was very low. LiF and LiCl salts were found to behave similarly. For LiBr- and LiI-based salts and mixtures, we pointed out a linear relationship between the water uptake and the elapsed time. Water uptake by magnesium oxide reached a limit after 200 h. This work provides a set of data concerning the rate of water uptake by single salts, salt mixtures and magnesia used in thermal battery electrolytes.

Quantification of tumour {sup 18}F-FDG uptake: Normalise to blood glucose or scale to liver uptake?

Energy Technology Data Exchange (ETDEWEB)

Keramida, Georgia [Brighton and Sussex Medical School, Clinical Imaging Sciences Centre, Brighton (United Kingdom); Brighton and Sussex University Hospitals NHS Trust, Department of Nuclear Medicine, Brighton (United Kingdom); University of Sussex, Clinical Imaging Sciences Centre, Brighton (United Kingdom); Dizdarevic, Sabina; Peters, A.M. [Brighton and Sussex Medical School, Clinical Imaging Sciences Centre, Brighton (United Kingdom); Brighton and Sussex University Hospitals NHS Trust, Department of Nuclear Medicine, Brighton (United Kingdom); Bush, Janice [Brighton and Sussex Medical School, Clinical Imaging Sciences Centre, Brighton (United Kingdom)

2015-09-15

To compare normalisation to blood glucose (BG) with scaling to hepatic uptake for quantification of tumour {sup 18}F-FDG uptake using the brain as a surrogate for tumours. Standardised uptake value (SUV) was measured over the liver, cerebellum, basal ganglia, and frontal cortex in 304 patients undergoing {sup 18}F-FDG PET/CT. The relationship between brain FDG clearance and SUV was theoretically defined. Brain SUV decreased exponentially with BG, with similar constants between cerebellum, basal ganglia, and frontal cortex (0.099-0.119 mmol/l{sup -1}) and similar to values for tumours estimated from the literature. Liver SUV, however, correlated positively with BG. Brain-to-liver SUV ratio therefore showed an inverse correlation with BG, well-fitted with a hyperbolic function (R = 0.83), as theoretically predicted. Brain SUV normalised to BG (nSUV) displayed a nonlinear correlation with BG (R = 0.55); however, as theoretically predicted, brain nSUV/liver SUV showed almost no correlation with BG. Correction of brain SUV using BG raised to an exponential power of 0.099 mmol/l{sup -1} also eliminated the correlation between brain SUV and BG. Brain SUV continues to correlate with BG after normalisation to BG. Likewise, liver SUV is unsuitable as a reference for tumour FDG uptake. Brain SUV divided by liver SUV, however, shows minimal dependence on BG. (orig.)

49 CFR 230.24 - Maximum allowable stress.

Science.gov (United States)

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Maximum allowable stress. 230.24 Section 230.24... Allowable Stress § 230.24 Maximum allowable stress. (a) Maximum allowable stress value. The maximum allowable stress value on any component of a steam locomotive boiler shall not exceed 1/4 of the ultimate...

Thyroid Scan and Uptake

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Full Text Available ... top of page Additional Information and Resources RTAnswers.org Radiation Therapy for Head and Neck Cancer top ... Scan and Uptake Sponsored by Please note RadiologyInfo.org is not a medical facility. Please contact your ...

Thyroid Scan and Uptake

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Full Text Available ... information about your thyroid’s size, shape, position and function that is often unattainable using other imaging procedures. ... thyroid uptake. It is a measurement of thyroid function, but does not involve imaging. Nuclear medicine is ...

Thyroid Scan and Uptake

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Full Text Available ... RAIU) is also known as a thyroid uptake. It is a measurement of thyroid function, but does ... they offer the potential to identify disease in its earliest stages as well as a patient’s immediate ...

Arsenic Uptake and Translocation in Plants.

Science.gov (United States)

Li, Nannan; Wang, Jingchao; Song, Won-Yong

2016-01-01

Arsenic (As) is a highly toxic metalloid that is classified as a non-threshold class-1 carcinogen. Millions of people worldwide suffer from As toxicity due to the intake of As-contaminated drinking water and food. Reducing the As concentration in drinking water and food is thus of critical importance. Phytoremediation of soil contaminated with As and the reduction of As contamination in food depend on a detailed understanding of As uptake and transport in plants. As transporters play essential roles in As uptake, translocation and accumulation in plant cells. In this review, we summarize the current understanding of As transport in plants, with an emphasis on As uptake, mechanisms of As resistance and the long-distance translocation of As, especially the accumulation of As in grains through phloem-mediated transport. © The Author 2015. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

X-rays as a probe of the Universe

Indian Academy of Sciences (India)

Table of contents. X-rays as a probe of the Universe · Probing the Universe ….. Flux = sT4 umax = 1011 T (in Kelvin) · History of x-ray astronomy · X-ray Production · X-ray spectra · Celestial sphere as seen by UHURU (1970) · Slide 8 · X-rays from accreting binary systems · Slide 10 · Neutron stars: Black Hole: · Primary X-ray ...

Excitatory amino acid-stimulated uptake of 22Na+ in primary astrocyte cultures

International Nuclear Information System (INIS)

Kimelberg, H.K.; Pang, S.; Treble, D.H.

1989-01-01

In this study we have found that L-glutamic acid, as well as being taken up by a Na+-dependent mechanism, will stimulate the uptake of 22Na+ by primary astrocyte cultures from rat brain in the presence of ouabain. By simultaneously measuring the uptake of 22Na+ and L-3H-glutamate a stoichiometry of 2-3 Na+ per glutamate was measured, implying electrogenic uptake. Increasing the medium K+ concentration to depolarize the cells inhibited L-3H-glutamate uptake, while calculations of the energetics of the observed L-3H-glutamate accumulation also supported an electrogenic mechanism of at least 2 Na+:1 glutamate. In contrast, kinetic analysis of the Na+ dependence of L-3H-glutamate uptake indicated a stoichiometry of Na+ to glutamate of 1:1, but further analysis showed that the stoichiometry cannot be resolved by purely kinetic studies. Studies with glutamate analogs, however, showed that kainic acid was a very effective stimulant of 22Na+ uptake, but 3H-kainic acid showed no Na+ -dependent uptake. Furthermore, while L-3H-glutamate uptake was very sensitive to lowered temperatures, glutamate-stimulated 22Na+ uptake was relatively insensitive. These results indicate that glutamate-stimulated uptake of 22Na+ in primary astrocytes cultures cannot be explained solely by cotransport of Na+ with glutamate, and they suggest that direct kainic acid-type receptor induced stimulation of Na+ uptake also occurs. Since both receptor and uptake effects involve transport of Na+, accurate measurements of the Na+ :glutamate stoichiometry for uptake can only be done using completely specific inhibitors of these 2 systems

Seeing the electroporative uptake of cell-membrane impermeable fluorescent molecules and nanoparticles

Science.gov (United States)

Kim, Kisoo; Kim, Jeong Ah; Lee, Soon-Geul; Lee, Won Gu

2012-07-01

This paper presents direct visualization of uptake directionality for cell-membrane impermeant fluorescent molecules and fluorescence-doped nanoparticles at a single-cell level during electroporation. To observe directly the uptake direction, we used microchannel-type electroporation that can generate a relatively symmetric and uniform electric field. For all the image frames during electroporation, fluorescence intensities that occurred at cell membranes in both uptake directions toward the electrodes have been sequentially recorded and quantitatively analyzed pixel by pixel. In our experiments, we found that fluorescent molecules, even not labeled to target biomolecules, had their own uptake direction with different intensities. It is also observed that the uptake intensity toward the cell membrane had a maximal value at a certain electric voltage, not at the highest value of voltages applied. The results also imply that the uptake direction of fluorescence-doped nanoparticles can be determined by a net surface charge of uptake materials and sizes in the electroporative environments. In summary, we performed a quantitative screening and direct visualization of uptake directionality for a set of fluorescent molecules and fluorescence-doped nanoparticles using electric-pulsation. Taking a closer look at the uptake direction of exogenous materials will help researchers to understand an unknown uptake phenomenon in which way foreign materials are inclined to move, and furthermore to design functional nanoparticles for electroporative gene delivery.This paper presents direct visualization of uptake directionality for cell-membrane impermeant fluorescent molecules and fluorescence-doped nanoparticles at a single-cell level during electroporation. To observe directly the uptake direction, we used microchannel-type electroporation that can generate a relatively symmetric and uniform electric field. For all the image frames during electroporation, fluorescence intensities

Positron emission tomography of tumour [{sup 18}F]fluoroestradiol uptake in patients with acquired hormone-resistant metastatic breast cancer prior to oestradiol therapy

Energy Technology Data Exchange (ETDEWEB)

Kruchten, Michel van; Schroeder, Carolien P.; Vries, Elisabeth G.E. de; Hospers, Geke A.P. [University of Groningen, Department of Medical Oncology, University Medical Centre Groningen (Netherlands); Glaudemans, Andor W.J.M.; Vries, Erik F.J. de [University of Groningen, Department of Nuclear Medicine and Molecular Imaging, University Medical Centre Groningen (Netherlands)

2015-10-15

Whereas anti-oestrogen therapy is widely applied to treat oestrogen receptor (ER) positive breast cancer, paradoxically, oestrogens can also induce tumour regression. Up-regulation of ER expression is a marker for oestrogen hypersensitivity. We, therefore, performed an exploratory study to evaluate positron emission tomography (PET) with the tracer 16α-[{sup 18}F]fluoro-17β-oestradiol ({sup 18}F-FES) as potential marker to select breast cancer patients for oestradiol therapy. Eligible patients had acquired endocrine-resistant metastatic breast cancer that progressed after ≥2 lines of endocrine therapy. All patients had prior ER-positive histology. Treatment consisted of oestradiol 2 mg, three times daily, orally. Patients underwent {sup 18}F-FES-PET/CT imaging at baseline. Tumour {sup 18}F-FES-uptake was quantified for a maximum of 20 lesions and expressed as maximum standardised uptake value (SUV{sub max}). CT-scan was repeated every 3 months to evaluate treatment response. Clinical benefit was defined as time to radiologic or clinical progression ≥24 weeks. {sup 18}F-FES uptake, quantified for 255 lesions in 19 patients, varied greatly between lesions (median 2.8; range 0.6-24.3) and between patients (median 2.5; range 1.1-15.5). Seven (37 %) patients experienced clinical benefit of oestrogen therapy, eight progressed (PD), and four were non-evaluable due to side effects. The positive and negative predictive value (PPV/NPV) of {sup 18}F-FES-PET for response to treatment were 60 % (95 % CI: 31-83 %) and 80 % (95 % CI: 38-96 %), respectively, using SUV{sub max} >1.5. {sup 18}F-FES-PET may aid identification of patients with acquired antihormone resistant breast cancer that are unlikely to benefit from oestradiol therapy. (orig.)

SUBSTRATE UPTAKE AND UTILIZATION BY A MARINE ULTRAMICROBACTERIUM

NARCIS (Netherlands)

SCHUT, F; JANSEN, M; GOMES, TMP; GOTTSCHAL, JC; HARDER, W; PRINS, RA

A facultatively oligotrophic ultramicrobacterium (strain RB2256) isolated from an Alaskan fjord by extinction dilution in seawater, was grown in batch culture and under single- and dual-substrate-limitation of alanine and glucose in a chemostat. The nature of the uptake systems, and the uptake

Increased brain fatty acid uptake in metabolic syndrome

DEFF Research Database (Denmark)

Karmi, Anna; Iozzo, Patricia; Viljanen, Antti

2010-01-01

To test whether brain fatty acid uptake is enhanced in obese subjects with metabolic syndrome (MS) and whether weight reduction modifies it.......To test whether brain fatty acid uptake is enhanced in obese subjects with metabolic syndrome (MS) and whether weight reduction modifies it....

High radio-isotope uptakes in patients with hypothyroidism

Energy Technology Data Exchange (ETDEWEB)

Wing, J.; Kalk, W.J.; Ganda, C. (University of the Witwatersrand, Johannesburg (South Africa). Dept. of Medicine)

1982-12-04

Hypothyroidism is usually associated with a low radio-isotope uptake by the thyriod gland. We report 8 cases of Hashimoto's thyroiditis with clinical and biochemical hypothyroidism and with borderline high or overtly increased technetium-99m pertechnetate and/or iodine-131 uptakes.

The Uptake by Plants of Diethylstilboestrol and of Its Glucuronide

DEFF Research Database (Denmark)

Gregers Hansen, B.

1964-01-01

The uptake of diethylstilboestrol and its glucuronide by plants could, under certain circumstances, present a potential health hazard. The relative uptake of the two compounds has therefore been studied in rye grass, red clover, mushrooms, and maize in pot and water culture experiments. It is con......The uptake of diethylstilboestrol and its glucuronide by plants could, under certain circumstances, present a potential health hazard. The relative uptake of the two compounds has therefore been studied in rye grass, red clover, mushrooms, and maize in pot and water culture experiments...

Nitrogen and Phosphorus Plant Uptake During Periods with no Photosynthesis Accounts for About Half of Global Annual Uptake

Science.gov (United States)

Riley, W. J.; Zhu, Q.; Tang, J.

2017-12-01

Uncertainties in current Earth System Model (ESM) predictions of terrestrial carbon-climate feedbacks over the 21st century are as large as, or larger than, any other reported natural system uncertainties. Soil Organic Matter (SOM) decomposition and photosynthesis, the dominant fluxes in this regard, are tightly linked through nutrient availability, and the recent Coupled Model Inter-comparison Project 5 (CMIP5) used for climate change assessment had no credible representations of these constraints. In response, many ESM land models (ESMLMs) have developed dynamic and coupled soil and plant nutrient cycles. Here we quantify terrestrial carbon cycle impacts from well-known observed plant nutrient uptake mechanisms ignored in most current ESMLMs. In particular, we estimate the global role of plant root nutrient competition with microbes and abiotic process at night and during the non-growing season using the ACME land model (ALMv1-ECA-CNP) that explicitly represents these dynamics. We first demonstrate that short-term nutrient uptake dynamics and competition between plants and microbes are accurately predicted by the model compared to 15N and 33P isotopic tracer measurements from more than 20 sites. We then show that global nighttime and non-growing season nitrogen and phosphorus uptake accounts for 46 and 45%, respectively, of annual uptake, with large latitudinal variation. Model experiments show that ignoring these plant uptake periods leads to large positive biases in annual N leaching (globally 58%) and N2O emissions (globally 68%). Biases these large will affect modeled carbon cycle dynamics over time, and lead to predictions of ecosystems that have overly open nutrient cycles and therefore lower capacity to sequester carbon.

A maximum power point tracking for photovoltaic-SPE system using a maximum current controller

Energy Technology Data Exchange (ETDEWEB)

Muhida, Riza [Osaka Univ., Dept. of Physical Science, Toyonaka, Osaka (Japan); Osaka Univ., Dept. of Electrical Engineering, Suita, Osaka (Japan); Park, Minwon; Dakkak, Mohammed; Matsuura, Kenji [Osaka Univ., Dept. of Electrical Engineering, Suita, Osaka (Japan); Tsuyoshi, Akira; Michira, Masakazu [Kobe City College of Technology, Nishi-ku, Kobe (Japan)

2003-02-01

Processes to produce hydrogen from solar photovoltaic (PV)-powered water electrolysis using solid polymer electrolysis (SPE) are reported. An alternative control of maximum power point tracking (MPPT) in the PV-SPE system based on the maximum current searching methods has been designed and implemented. Based on the characteristics of voltage-current and theoretical analysis of SPE, it can be shown that the tracking of the maximum current output of DC-DC converter in SPE side will track the MPPT of photovoltaic panel simultaneously. This method uses a proportional integrator controller to control the duty factor of DC-DC converter with pulse-width modulator (PWM). The MPPT performance and hydrogen production performance of this method have been evaluated and discussed based on the results of the experiment. (Author)

Metaiodobenzylguanidine (MIBG) uptake in Parkinson's disease also decreases at thyroid

International Nuclear Information System (INIS)

Matsui, Hideaki; Udaka, Fukashi; Oda, Masaya; Tamura, Akiko; Kubori, Tamotsu; Nishinaka, Kazuto; Kameyama, Masakuni

2005-01-01

Decreased cardiac metaiodobenzylguanidine (MIBG) uptake was reported in Parkinson's disease and this contributes to the differential diagnosis between Parkinson's disease and other forms of parkinsonism such as multiple system atrophy. However, decreased MIBG uptake of the thyroid has not been demonstrated. The objective of this study was to compare MIBG uptake of the thyroid among Parkinson's disease, multiple system atrophy and controls. Twenty-six patients with Parkinson's disease, 11 patients with multiple system atrophy and 14 controls were examined in this study. Planar images were taken 15 minutes (early images) and 3 hours (late images) after intravenous injection of 111 MBq 123 I-MIBG. MIBG uptake of the thyroid on early images decreased significantly in Parkinson's disease compared to controls (p<0.0001) and multiple system atrophy (p=0.018). MIBG uptake of the thyroid on early images decreased significantly also in multiple system atrophy compared to controls (p=0.027). On late images, thyroid uptake differed significantly only between Parkinson's disease and controls (p=0.010). Our study is the first to demonstrate decreased MIBG uptake of the thyroid in Parkinson's disease. Sympathetic nervous denervation of Parkinson's disease occurred not only in the heart but also in the thyroid. (author)

Sphagnum mosses--masters of efficient N-uptake while avoiding intoxication.

Science.gov (United States)

Fritz, Christian; Lamers, Leon P M; Riaz, Muhammad; van den Berg, Leon J L; Elzenga, Theo J T M

2014-01-01

Peat forming Sphagnum mosses are able to prevent the dominance of vascular plants under ombrotrophic conditions by efficiently scavenging atmospherically deposited nitrogen (N). N-uptake kinetics of these mosses are therefore expected to play a key role in differential N availability, plant competition, and carbon sequestration in Sphagnum peatlands. The interacting effects of rain N concentration and exposure time on moss N-uptake rates are, however, poorly understood. We investigated the effects of N-concentration (1, 5, 10, 50, 100, 500 µM), N-form ((15)N-ammonium or nitrate) and exposure time (0.5, 2, 72 h) on uptake kinetics for Sphagnum magellanicum from a pristine bog in Patagonia (Argentina) and from a Dutch bog exposed to decades of N-pollution. Uptake rates for ammonium were higher than for nitrate, and N-binding at adsorption sites was negligible. During the first 0.5 h, N-uptake followed saturation kinetics revealing a high affinity (Km 3.5-6.5 µM). Ammonium was taken up 8 times faster than nitrate, whereas over 72 hours this was only 2 times. Uptake rates decreased drastically with increasing exposure times, which implies that many short-term N-uptake experiments in literature may well have overestimated long-term uptake rates and ecosystem retention. Sphagnum from the polluted site (i.e. long-term N exposure) showed lower uptake rates than mosses from the pristine site, indicating an adaptive response. Sphagnum therefore appears to be highly efficient in using short N pulses (e.g. rainfall in pristine areas). This strategy has important ecological and evolutionary implications: at high N input rates, the risk of N-toxicity seems to be reduced by lower uptake rates of Sphagnum, at the expense of its long-term filter capacity and related competitive advantage over vascular plants. As shown by our conceptual model, interacting effects of N-deposition and climate change (changes in rainfall) will seriously alter the functioning of Sphagnum peatlands.

Sphagnum Mosses - Masters of Efficient N-Uptake while Avoiding Intoxication

Science.gov (United States)

Fritz, Christian; Lamers, Leon P. M.; Riaz, Muhammad; van den Berg, Leon J. L.; Elzenga, Theo J. T. M.

2014-01-01

Peat forming Sphagnum mosses are able to prevent the dominance of vascular plants under ombrotrophic conditions by efficiently scavenging atmospherically deposited nitrogen (N). N-uptake kinetics of these mosses are therefore expected to play a key role in differential N availability, plant competition, and carbon sequestration in Sphagnum peatlands. The interacting effects of rain N concentration and exposure time on moss N-uptake rates are, however, poorly understood. We investigated the effects of N-concentration (1, 5, 10, 50, 100, 500 µM), N-form (15N - ammonium or nitrate) and exposure time (0.5, 2, 72 h) on uptake kinetics for Sphagnum magellanicum from a pristine bog in Patagonia (Argentina) and from a Dutch bog exposed to decades of N-pollution. Uptake rates for ammonium were higher than for nitrate, and N-binding at adsorption sites was negligible. During the first 0.5 h, N-uptake followed saturation kinetics revealing a high affinity (Km 3.5–6.5 µM). Ammonium was taken up 8 times faster than nitrate, whereas over 72 hours this was only 2 times. Uptake rates decreased drastically with increasing exposure times, which implies that many short-term N-uptake experiments in literature may well have overestimated long-term uptake rates and ecosystem retention. Sphagnum from the polluted site (i.e. long-term N exposure) showed lower uptake rates than mosses from the pristine site, indicating an adaptive response. Sphagnum therefore appears to be highly efficient in using short N pulses (e.g. rainfall in pristine areas). This strategy has important ecological and evolutionary implications: at high N input rates, the risk of N-toxicity seems to be reduced by lower uptake rates of Sphagnum, at the expense of its long-term filter capacity and related competitive advantage over vascular plants. As shown by our conceptual model, interacting effects of N-deposition and climate change (changes in rainfall) will seriously alter the functioning of Sphagnum peatlands

Muscle contraction increases carnitine uptake via translocation of OCTN2

Energy Technology Data Exchange (ETDEWEB)

Furuichi, Yasuro [Graduate School of Natural Science and Technology, Kanazawa University, Kanazawa (Japan); Sugiura, Tomoko; Kato, Yukio [Faculty of Pharmacy, Kanazawa University, Kanazawa (Japan); Takakura, Hisashi [Faculty of Human Sciences, Kanazawa University, Kanazawa (Japan); Hanai, Yoshiteru [Nagoya Institute of Technology, Nagoya (Japan); Hashimoto, Takeshi [Ritsumeikan University, Kusatsu (Japan); Masuda, Kazumi, E-mail: masuda@ed.kanazawa-u.ac.jp [Faculty of Human Sciences, Kanazawa University, Kanazawa (Japan)

2012-02-24

Highlights: Black-Right-Pointing-Pointer Muscle contraction augmented carnitine uptake into rat hindlimb muscles. Black-Right-Pointing-Pointer An increase in carnitine uptake was due to an intrinsic clearance, not blood flow. Black-Right-Pointing-Pointer Histochemical analysis showed sarcolemmal OCTN2 was emphasized after contraction. Black-Right-Pointing-Pointer OCTN2 protein in sarcolemmal fraction was increased in contracting muscles. -- Abstract: Since carnitine plays an important role in fat oxidation, influx of carnitine could be crucial for muscle metabolism. OCTN2 (SLC22A5), a sodium-dependent solute carrier, is assumed to transport carnitine into skeletal muscle cells. Acute regulation of OCTN2 activity in rat hindlimb muscles was investigated in response to electrically induced contractile activity. The tissue uptake clearance (CL{sub uptake}) of L-[{sup 3}H]carnitine during muscle contraction was examined in vivo using integration plot analysis. The CL{sub uptake} of [{sup 14}C]iodoantipyrine (IAP) was also determined as an index of tissue blood flow. To test the hypothesis that increased carnitine uptake involves the translocation of OCTN2, contraction-induced alteration in the subcellular localization of OCTN2 was examined. The CL{sub uptake} of L-[{sup 3}H]carnitine in the contracting muscles increased 1.4-1.7-fold as compared to that in the contralateral resting muscles (p < 0.05). The CL{sub uptake} of [{sup 14}C]IAP was much higher than that of L-[{sup 3}H]carnitine, but no association between the increase in carnitine uptake and blood flow was obtained. Co-immunostaining of OCTN2 and dystrophin (a muscle plasma membrane marker) showed an increase in OCTN2 signal in the plasma membrane after muscle contraction. Western blotting showed that the level of sarcolemmal OCTN2 was greater in contracting muscles than in resting muscles (p < 0.05). The present study showed that muscle contraction facilitated carnitine uptake in skeletal muscles, possibly

Muscle contraction increases carnitine uptake via translocation of OCTN2

International Nuclear Information System (INIS)

Furuichi, Yasuro; Sugiura, Tomoko; Kato, Yukio; Takakura, Hisashi; Hanai, Yoshiteru; Hashimoto, Takeshi; Masuda, Kazumi

2012-01-01

Highlights: ► Muscle contraction augmented carnitine uptake into rat hindlimb muscles. ► An increase in carnitine uptake was due to an intrinsic clearance, not blood flow. ► Histochemical analysis showed sarcolemmal OCTN2 was emphasized after contraction. ► OCTN2 protein in sarcolemmal fraction was increased in contracting muscles. -- Abstract: Since carnitine plays an important role in fat oxidation, influx of carnitine could be crucial for muscle metabolism. OCTN2 (SLC22A5), a sodium-dependent solute carrier, is assumed to transport carnitine into skeletal muscle cells. Acute regulation of OCTN2 activity in rat hindlimb muscles was investigated in response to electrically induced contractile activity. The tissue uptake clearance (CL uptake ) of L-[ 3 H]carnitine during muscle contraction was examined in vivo using integration plot analysis. The CL uptake of [ 14 C]iodoantipyrine (IAP) was also determined as an index of tissue blood flow. To test the hypothesis that increased carnitine uptake involves the translocation of OCTN2, contraction-induced alteration in the subcellular localization of OCTN2 was examined. The CL uptake of L-[ 3 H]carnitine in the contracting muscles increased 1.4–1.7-fold as compared to that in the contralateral resting muscles (p uptake of [ 14 C]IAP was much higher than that of L-[ 3 H]carnitine, but no association between the increase in carnitine uptake and blood flow was obtained. Co-immunostaining of OCTN2 and dystrophin (a muscle plasma membrane marker) showed an increase in OCTN2 signal in the plasma membrane after muscle contraction. Western blotting showed that the level of sarcolemmal OCTN2 was greater in contracting muscles than in resting muscles (p < 0.05). The present study showed that muscle contraction facilitated carnitine uptake in skeletal muscles, possibly via the contraction-induced translocation of its specific transporter OCTN2 to the plasma membrane.

Impact of Glycerol as Carbon Source onto Specific Sugar and Inducer Uptake Rates and Inclusion Body Productivity in E. coli BL21(DE3

Directory of Open Access Journals (Sweden)

Julian Kopp

2017-12-01

Full Text Available The Gram-negative bacterium E. coli is the host of choice for a multitude of used recombinant proteins. Generally, cultivation is easy, media are cheap, and a high product titer can be obtained. However, harsh induction procedures using isopropyl β-d-1 thiogalactopyranoside as inducer are often referred to cause stress reactions, leading to a phenomenon known as “metabolic” or “product burden”. These high expressions of recombinant proteins mainly result in decreased growth rates and cell lysis at elevated induction times. Therefore, approaches tend to use “soft” or “tunable” induction with lactose and reduce the stress level of the production host. The usage of glucose as energy source in combination with lactose as induction reagent causes catabolite repression effects on lactose uptake kinetics and as a consequence reduced product titer. Glycerol—as an alternative carbon source—is already known to have positive impact on product formation when coupled with glucose and lactose in auto-induction systems, and has been referred to show no signs of repression when cultivated with lactose concomitantly. In recent research activities, the impact of different products on the lactose uptake using glucose as carbon source was highlighted, and a mechanistic model for glucose-lactose induction systems showed correlations between specific substrate uptake rate for glucose or glycerol (qs,C and the maximum specific lactose uptake rate (qs,lac,max. In this study, we investigated the mechanistic of glycerol uptake when using the inducer lactose. We were able to show that a product-producing strain has significantly higher inducer uptake rates when being compared to a non-producer strain. Additionally, it was shown that glycerol has beneficial effects on viability of cells and on productivity of the recombinant protein compared to glucose.

Calcidiol and vitamin D binding protein uptake by LLC-PK1 cells

International Nuclear Information System (INIS)

Keenan, M.J.; Holmes, R.P.

1986-01-01

The process by which target cells take up vitamin D and its metabolites is not known. The authors studied the uptake of both 3 H-calcidiol and 125 I-Vitamin D Binding Protein (DBP) by LLC-PK 1 cells. Uptake was directly related to their extracellular concentrations. In the presence of 55 serum in the growth media cells previously incubated with 10 nM calcitriol for 4 hr had a greater uptake of calcidiol than those cells not incubated with calcitriol. This effect of calcitriol on calcidiol uptake was absent when cells were grown in hormone-supplemented, serum-free media, despite these cells having a cytosolic calcitriol receptor. Equal uptake of calcidiol occurred when DBP was absent and when DBP was present in a one to one molar ratio to calcidiol. With a 1:1 ratio of DBP to calcidiol and a measured K/sub D/ of 2 x 10 -8 M, the uptake of calcidiol could not be accounted for by uptake of the free ligand alone. A large excess of DBP (100:1) in relation to calcidiol suppressed uptake of calcidiol by approx. 90%. The authors have not been able to identify a saturable, specific uptake of either calcidiol or DBP despite DBP appearing to facilitate calcidiol uptake

Heavy Metal uptake Potentials of Pseudomonas aeruginosa and ...

African Journals Online (AJOL)

Uptake of heavy metals, silver and cadmium by Pseudomonas aeruginosa (a Gram negative bacterium) and Micrococcus luteus (a Gram positive bacterium) was investigated in Cadmium and Silver stock solution using ion selective electrodes. Silver and cadmium uptake by the two organisms was described by Langmuir ...

Reduction of the influence of the liver uptake to the myocardial uptake on technetium-99m myocardial SPECT. Usefulness and problems of a mask processing method

Energy Technology Data Exchange (ETDEWEB)

Takaki, Akihiro; Okada, Kazuhiro; Urata, Johji; Matsuda, Hirofumi; Takao, Yuji [Saiseikai Kumamoto Hospital (Japan)

1999-07-01

The aim of this study is to evaluate the usefulness of a mask processing method for obtaining the true myocardial tracer distribution by eliminating the influence of the liver uptake to the myocardial uptake on myocardial SPECT images by using technetium-99m ({sup 99m}Tc) blood flow agents. A SPECT imaging was performed with a two-head SPECT system (GCA-7200A/DI) in both phantom and clinical studies. The mask processing method was applied to the reconstructed and projection images. The phantom consisted of heart, lung, liver and spine. A defect was located in the inferior wall of the left ventricle and other parts of the heart and liver were filled with {sup 99m}Tc solution. For clinical study 10 patients with difficulty in the interpretation of the inferior wall were selected for the evaluation of usefulness of the mask method. In the phantom study, the mask processing method applied to the reconstructed images was able to remove the overlapped liver from the heart, but was not able to remove the influence of the liver uptake to the myocardial uptake. Nevertheless, the mask processing method applied to the projection images successfully eliminated not only the overlapped liver but also the influence of the liver uptake to the myocardial uptake. In the clinical study, the liver uptake could be removed from the uptake in the inferior wall in 8 of 10 patients with the mask processing methods. In 2 patients, the overlapped liver uptake could not be eliminated from the uptake in the inferior wall because the distance between the liver and heart was too short. The mask processing method applied to the projection images was thought to be superior to that applied to the reconstruction images in both phantom and clinical studies. The mask processing method, especially applied to the projection images, seems to be useful for the elimination of the liver uptake from the inferior wall of the myocardium on myocardial SPECT images using {sup 99m}Tc blood flow agents. (author)

Reduction of the influence of the liver uptake to the myocardial uptake on technetium-99m myocardial SPECT. Usefulness and problems of a mask processing method

International Nuclear Information System (INIS)

Takaki, Akihiro; Okada, Kazuhiro; Urata, Johji; Matsuda, Hirofumi; Takao, Yuji

1999-01-01

The aim of this study is to evaluate the usefulness of a mask processing method for obtaining the true myocardial tracer distribution by eliminating the influence of the liver uptake to the myocardial uptake on myocardial SPECT images by using technetium-99m ( 99m Tc) blood flow agents. A SPECT imaging was performed with a two-head SPECT system (GCA-7200A/DI) in both phantom and clinical studies. The mask processing method was applied to the reconstructed and projection images. The phantom consisted of heart, lung, liver and spine. A defect was located in the inferior wall of the left ventricle and other parts of the heart and liver were filled with 99m Tc solution. For clinical study 10 patients with difficulty in the interpretation of the inferior wall were selected for the evaluation of usefulness of the mask method. In the phantom study, the mask processing method applied to the reconstructed images was able to remove the overlapped liver from the heart, but was not able to remove the influence of the liver uptake to the myocardial uptake. Nevertheless, the mask processing method applied to the projection images successfully eliminated not only the overlapped liver but also the influence of the liver uptake to the myocardial uptake. In the clinical study, the liver uptake could be removed from the uptake in the inferior wall in 8 of 10 patients with the mask processing methods. In 2 patients, the overlapped liver uptake could not be eliminated from the uptake in the inferior wall because the distance between the liver and heart was too short. The mask processing method applied to the projection images was thought to be superior to that applied to the reconstruction images in both phantom and clinical studies. The mask processing method, especially applied to the projection images, seems to be useful for the elimination of the liver uptake from the inferior wall of the myocardium on myocardial SPECT images using 99m Tc blood flow agents. (author)

Forest Transpiration: Resolving Species-Specific Root Water Uptake Patterns

Science.gov (United States)

Blume, T.; Heidbuechel, I.; Simard, S.; Guntner, A.; Weiler, M.; Stewart, R. D.

2016-12-01

Transpiration and its spatio-temporal variability are still not fully understood, despite their importance for the global water cycle. This is in part due to our inability to measure transpiration comprehensively. Transpiration is usually either estimated with empirical equations based on climatic variables and crop factors, by measuring sap velocities, estimating sap wood area and scaling up to the forest stand based on a number of assumptions or by measuring the integral signal across a footprint with eddy flux towers. All these methods are focused on the cumulated loss of water to the atmosphere and do not provide information on where this water is coming from. In this study, spatio-temporal variability of root water uptake was investigated in a forest in the northeastern German lowlands. The soils are sandy and the depth of the unsaturated zone ranges from 1 to 30 m. We estimated root water uptake from different soil depths, from 0.1 m down to 2 m, based on diurnal fluctuations in soil moisture content during rain-free days. The 15 field sites cover different topographic positions and forest stands: 4 pure stands of both mature and young beech and pine and 9 mixed stands. The resulting daily data set of root water uptake shows that the forest stands differ in total amounts as well as in uptake depth distributions. Temporal dynamics of signal strength within the profile suggest a locally shifting spatial distribution of uptake that changes with water availability. The relationship of these depth-resolved uptake rates to overall soil water availability varies considerably between tree species. Using the physically-based soil hydrological model HYDRUS we investigated to what extent the observed patterns in uptake can be related to soil physical relationships alone and where tree species-specific aspects come into play. We furthermore used the model to test assumptions and estimate uncertainties of this soil moisture based estimation of plant water uptake. The

Kinetic parameters of silicon uptake by rice cultivars

Directory of Open Access Journals (Sweden)

Priscila Oliveira Martins

2012-02-01

Full Text Available Silicon is considered an important chemical element for rice, because it can improve tolerance to biotic and abiotic stress. However, in many situations no positive effect of silicon was observed, probably due to genetic factors. The objective of this research was to monitor Si uptake kinetics and identify responses of rice cultivars in terms of Si uptake capacity and use. The experiment was carried out in a greenhouse of the São Paulo State University (UNESP, Brazil. The experiment was arranged in a completely randomized, factorial design with three replications. that consisted of two rice cultivars and two Si levels. Kinetic parameters (Vmax, Km, and Cmin, root morphology variables, dry matter yield, Si accumulation and levels in shoots and roots, uptake efficiency, utilization efficiency, and root/shoot ratio were evaluated. Higher Si concentrations in the nutrient solution did not increase rice dry matter. The development of the low-affinity silicon uptake system of the rice cultivar 'Caiapó' was better than of 'Maravilha'.

Characteristics of sugar uptake by immature maize embryos

International Nuclear Information System (INIS)

Griffith, S.M.; Jones, R.J.; Brenner, M.L.

1986-01-01

Characteristics of sugar uptake by immature maize embryos were determined in vitro utilizing a 14 C-sugar solution incubation method. Hexose uptake rates were greater than those for sucrose, however, all showed biphasic kinetics. Glucose and fructose saturable components were evidence at <50 mM and sucrose at <5 mM. Chemical inhibitors (CCCP, DNP, NaCN, and PCMBS) and low temperature reduced sugar uptake. Sucrose influx was pH dependent while glucose was not. Embryos maintained a high sucrose to hexose ratio throughout development. At 25 days after pollination sucrose levels exceeded 200 mM while hexose levels remained below 5 mM. Glucose was rapidly converted to sucrose upon transport into the embryo. These circumstantial data indicate that sugar uptake by immature maize embryos is metabolically dependent and carrier mediated. Furthermore, sucrose transport appears to occur against its concentration gradient involving a H+/sucrose cotransport mechanism, while glucose influx is driven by its concentration gradient and subsequent metabolism

Lung damage and pulmonary uptake of serotonin in intact dogs

International Nuclear Information System (INIS)

Dawson, C.A.; Christensen, C.W.; Rickaby, D.A.; Linehan, J.H.; Johnston, M.R.

1985-01-01

The authors examined the influence of glass bead embolization and oleic acid, dextran, and imipramine infusion on the pulmonary uptake of trace doses of [ 3 H]serotonin and the extravascular volume accessible to [ 14 C]antipyrine in anesthetized dogs. Embolization and imipramine decreased serotonin uptake by 53 and 61%, respectively, but no change was observed with oleic acid or dextran infusion. The extravascular volume accessible to the antipyrine was reduced by 77% after embolization and increased by 177 and approximately 44% after oleic acid and dextran infusion, respectively. The results suggest that when the perfused endothelial surface is sufficiently reduced, as with embolization, the uptake of trace doses of serotonin will be depressed. In addition, decreases in serotonin uptake in response to imipramine in this study and in response to certain endothelial toxins in other studies suggest that serotonin uptake can reveal certain kinds of changes in endothelial function. However, the lack of a response to oleic acid-induced damage in the present study suggests that serotonin uptake is not sensitive to all forms of endothelial damage

Higher renewable energy integration into the existing energy system of Finland – Is there any maximum limit?

International Nuclear Information System (INIS)

Zakeri, Behnam; Syri, Sanna; Rinne, Samuli

2015-01-01

Finland is to increase the share of RES (renewable energy sources) up to 38% in final energy consumption by 2020. While benefiting from local biomass resources Finnish energy system is deemed to achieve this goal, increasing the share of other intermittent renewables is under development, namely wind power and solar energy. Yet the maximum flexibility of the existing energy system in integration of renewable energy is not investigated, which is an important step before undertaking new renewable energy obligations. This study aims at filling this gap by hourly analysis and comprehensive modeling of the energy system including electricity, heat, and transportation, by employing EnergyPLAN tool. Focusing on technical and economic implications, we assess the maximum potential of different RESs separately (including bioenergy, hydropower, wind power, solar heating and PV, and heat pumps), as well as an optimal mix of different technologies. Furthermore, we propose a new index for assessing the maximum flexibility of energy systems in absorbing variable renewable energy. The results demonstrate that wind energy can be harvested at maximum levels of 18–19% of annual power demand (approx. 16 TWh/a), without major enhancements in the flexibility of energy infrastructure. With today's energy demand, the maximum feasible renewable energy for Finland is around 44–50% by an optimal mix of different technologies, which promises 35% reduction in carbon emissions from 2012's level. Moreover, Finnish energy system is flexible to augment the share of renewables in gross electricity consumption up to 69–72%, at maximum. Higher shares of RES calls for lower energy consumption (energy efficiency) and more flexibility in balancing energy supply and consumption (e.g. by energy storage). - Highlights: • By hourly analysis, we model the whole energy system of Finland. • With existing energy infrastructure, RES (renewable energy sources) in primary energy cannot go beyond 50%. �

Benign ovarian and endometrial uptake on FDG PET-CT. Patterns and pitfalls

International Nuclear Information System (INIS)

Liu, Y.

2009-01-01

Increased ovarian or endometrial uptake may cause a dilemma in the interpretation of whole body F18-fluorodeoxyglucose-positron emission tomography (FDG-PET) imaging or even misdiagnosis of malignant disease. Knowledge of benign FDG uptake of the ovaries and uterus is important for daily practice of nuclear medicine radiologists. Increased uptake in the ovaries or uterus indicates a pathologic or neoplastic process in postmenopausal patients. In premenopausal women, increased ovarian or endometrial uptake can be functional or malignant. Benign functional uptake of premenopausal ovaries or uterus is related to the menstrual cycle; therefore, information about the patient's menstrual status is crucial for interpretation. In addition, correlation with computed tomography (CT), especially diagnostic CT acquired at the same time of PET/CT is very useful in clarifying the location of the uptake and the existence or disappearance of the discrete lesion. Increased ovarian uptake may also be identified in histologically different benign tumor entities. Nonmenstrual-related endometrial uptake may be present in many benign diseases as well. (author)

Lake Basin Fetch and Maximum Length/Width

Data.gov (United States)

Minnesota Department of Natural Resources — Linear features representing the Fetch, Maximum Length and Maximum Width of a lake basin. Fetch, maximum length and average width are calcuated from the lake polygon...

Radiolabeling as a tool to study uptake pathways in plants

Energy Technology Data Exchange (ETDEWEB)

Schymura, Stefan; Hildebrand, Heike; Franke, Karsten [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Reactive Transport; Fricke, T. [Vita34 BioPlanta, Leipzig (Germany)

2017-06-01

The identification of major uptake pathways in plants is an important factor when evaluation the fate of manufactured nanoparticles in the environment and the associated risks. Using different radiolabeling techniques we were able to show a predominantly particulate uptake for CeO{sub 2} nanoparticles (NPs) in contrast to a possible uptake in the form of ionic cerium.

Stereoselective effects of MDMA on inhibition of monoamine uptake

International Nuclear Information System (INIS)

Steele, T.D.; Nichols, D.E.; Yim, G.K.W.

1986-01-01

The R(-)-isomers of hallucinogenic phenylisopropylamines are most active, whereas the S(+)-enantiomers of amphetamine (AMPH) and methylenedioxymethamphetamine (MDMA) are more potent centrally. To determine if MDMA exhibits stereoselective effects at the biochemical level that resemble either those of amphetamine or the potent hallucinogen 2,5-dimethoxy-4-methylamphetamine (DOM), the ability of the isomers of MDMA, AMPH and DOM to inhibit uptake of radiolabelled monoamines into synaptosomes was measured. AMPH was more potent than MDMA in inhibiting uptake of 3 H-norepinephrine (NE) into hypothalamic synaptosomes and 3 H-dopamine (DA) into striatal synaptosomes. The S(+)-isomer was more active in each case. MDMA was more potent than AMPH in inhibiting uptake of 3 H-serotonin (5-HT) into hippocampal synaptosomes and exhibited a high degree of stereoselectivity, in favor of the S(+)-isomer. DOM showed only minimal activity in inhibiting uptake of any monoamine (IC 50 > 10 -5 M). These results suggest that MDMA exhibits stereoselective effects similar to those of amphetamine on monoamine uptake inhibition, a parameter that is unrelated to the mechanism of action of the hallucinogen DOM

Unmasking the Role of Uptake Transporters for Digoxin Uptake Across the Barriers of the Central Nervous System in Rat

Directory of Open Access Journals (Sweden)

Kunal S Taskar

2017-03-01

Full Text Available The role of uptake transporter (organic anion–transporting polypeptide [Oatp] in the disposition of a P-glycoprotein (P-gp substrate (digoxin at the barriers of central nervous system, namely, the blood-brain barrier (BBB, blood-spinal cord barrier (BSCB, and brain-cerebrospinal fluid barrier (BCSFB, was studied using rat as a preclinical species. In vivo chemical inhibition of P-gp and Oatp was achieved using elacridar and rifampicin, respectively. Our findings show that (1 digoxin had a low brain-to-plasma concentration ratio (B/P (0.07 in rat; (2 in the presence of elacridar, the B/P of digoxin increased by about 12-fold; (3 rifampicin administration alone did not change the digoxin B/P significantly when compared with digoxin B/P alone; (4 rifampicin administration along with elacridar resulted only in 6-fold increase in the B/P of digoxin; (5 similar fold changes and trends were seen with the spinal cord-to-plasma concentration ratio of digoxin, indicating the similarity between BBB and the BSCB; and (6 unlike BBB and BSCB, the presence of rifampicin further increased the cerebrospinal fluid-to-plasma concentration ratio (CSF/P for digoxin, suggesting a differential orientation of the uptake transporters at the BCSFB (CSF to blood compared with the BBB (blood to brain. The observations for digoxin uptake, at least at the BBB and the BSCB, advocate the importance of uptake transporters (Oatps. However, the activity of such uptake transporters became evident only after inhibition of the efflux transporter (P-gp.

Maximum permissible voltage of YBCO coated conductors

Energy Technology Data Exchange (ETDEWEB)

Wen, J.; Lin, B.; Sheng, J.; Xu, J.; Jin, Z. [Department of Electrical Engineering, Shanghai Jiao Tong University, Shanghai (China); Hong, Z., E-mail: zhiyong.hong@sjtu.edu.cn [Department of Electrical Engineering, Shanghai Jiao Tong University, Shanghai (China); Wang, D.; Zhou, H.; Shen, X.; Shen, C. [Qingpu Power Supply Company, State Grid Shanghai Municipal Electric Power Company, Shanghai (China)

2014-06-15

Highlights: • We examine three kinds of tapes’ maximum permissible voltage. • We examine the relationship between quenching duration and maximum permissible voltage. • Continuous I{sub c} degradations under repetitive quenching where tapes reaching maximum permissible voltage. • The relationship between maximum permissible voltage and resistance, temperature. - Abstract: Superconducting fault current limiter (SFCL) could reduce short circuit currents in electrical power system. One of the most important thing in developing SFCL is to find out the maximum permissible voltage of each limiting element. The maximum permissible voltage is defined as the maximum voltage per unit length at which the YBCO coated conductors (CC) do not suffer from critical current (I{sub c}) degradation or burnout. In this research, the time of quenching process is changed and voltage is raised until the I{sub c} degradation or burnout happens. YBCO coated conductors test in the experiment are from American superconductor (AMSC) and Shanghai Jiao Tong University (SJTU). Along with the quenching duration increasing, the maximum permissible voltage of CC decreases. When quenching duration is 100 ms, the maximum permissible of SJTU CC, 12 mm AMSC CC and 4 mm AMSC CC are 0.72 V/cm, 0.52 V/cm and 1.2 V/cm respectively. Based on the results of samples, the whole length of CCs used in the design of a SFCL can be determined.

Fluorine uptake into the human tooth from a thin layer of F-releasing material

International Nuclear Information System (INIS)

Yamamoto, H.; Nomachi, M.; Yasuda, K.; Iwami, Y.; Ebisu, S.; Komatsu, H.; Sakai, T.; Kamiya, T.

2007-01-01

Using the proton induced gamma-ray emission (PIGE) method (TIARA, Japan), we have studied fluorine (F) distribution in the human tooth under various conditions. Here, we report F uptake into the human tooth from a thin layer of F-releasing low viscous resin (FLVR). Crowns of human teeth were horizontally cut and the dentin of the cut surface was first covered with four kinds of FLVR (FL-Bond, Reactmer Bond, Xeno Bond, and Protect Liner F; thickness, 50-150 μm) according to the manufacturers' instructions. Non-F-releasing and F-releasing filling resins were also hardened, on the cut surfaces of crowns covered with four kinds of FLVR thin layers. The type of the non-F-releasing filling materials used was LITE FIL IIP: G1-A (FL-Bond and LITE FIL IIP), G2-A (Reactmer Bond and LITE FIL IIP), G3-A (Xeno Bond and LITE FIL IIP), and G4-A (Protect Liner F and LITE FIL IIP). The types of F-releasing filling materials used were G1-B (FL-Bond and Beautifil), G2-B (Reactmer Bond and Reactmer Paste), G3-B (Xeno Bond and Xeno CF Paste), and G4-B (Protect Liner F and Teethmate F-1). Treatment and measurements of specimens were the same as previously reported [H. Yamamoto, M. Nomahci, K. Yasuda, Y. Iwami, S. Ebisu, N. Yamamoto, T. Sakai, T. Kamiya, Nucl. Instr. and Meth. B 210 (2003) 388]. F uptake from specimens following one month of application was estimated from 2-D maps. F penetration was observed in all teeth of G1-A-G4-A groups. The maximum values of F concentration in each tooth and F penetration depth were larger for larger F concentrations in FLVR. FLVR was useful for the F uptake into the tooth, and the F distribution near the thin layer of FLVR depended on the materials used. Between G1-A and G1-B or G4-A and G4-B, the F uptake was significantly different. We were able to obtain fundamental data, which were useful for the analysis of F transportation relating to prevention of caries

Gastrointestinal uptake and fate of cadmium in rainbow trout acclimated to sublethal dietary cadmium

International Nuclear Information System (INIS)

Chowdhury, M.J.; McDonald, D.G.; Wood, C.M.

2004-01-01

Adult rainbow trout were pre-exposed to a sublethal concentration of dietary Cd (500 mg/kg dry wt.) for 30 days to induce acclimation. A gastrointestinal dose of radiolabeled Cd (276 μg/kg wet wt.) was infused into the stomach of non-acclimated and Cd-acclimated trout through a stomach catheter. Repetitive blood samples over 24 h and terminal tissue samples were taken to investigate the gastrointestinal uptake, plasma clearance kinetics, and tissue distribution of Cd. Only a small fraction of the infused dose (non-acclimated: 2.4%; Cd-acclimated: 6.6%) was internalized across the gut wall, while most was bound in the gut tissues (10-24%) or remained in the lumen (16-33%) or lost from the fish (∼50%) over 24 h. Cadmium loading during pre-exposure produced a profound increase of total Cd in the blood plasma (∼28-fold) and red blood cells (RBC; ∼20-fold). The plasma Cd-time profiles consisted of an apparent rising (uptake) phase and a declining (clearance) phase with a maximum value of uptake in 4 h, suggesting that uptake of gastrointestinally infused Cd was very rapid. Acclimation to dietary Cd did not affect plasma Cd clearance (∼0.5 ml/min), but enhanced new Cd levels in the plasma (but not in the RBC), and resulted in a longer half-life for plasma Cd. Tissue total and new Cd levels varied in different regions of the gastrointestinal tract, and overall levels in gut tissues were much greater than in non-gut tissues, reflecting the Cd exposure route. Dietary Cd, but not the infused Cd, greatly increased total Cd levels of all gut tissues in the order posterior-intestine (640-fold) > cecae (180-fold) > mid-intestine (94-fold) > stomach (53-fold) in Cd-acclimated fish relative to naieve fish. Among non-gut tissues in the Cd-acclimated fish, the great increases of total Cd levels were observed in the liver (73-fold), kidney (39-fold), carcass (35-fold), and gills (30-fold). The results provide some clear conclusions that may be useful for environmental risk

Fluorine uptake into the human tooth from a thin layer of F-releasing material

Energy Technology Data Exchange (ETDEWEB)

Yamamoto, H. [Department of Restorative Dentistry and Endodontology, Graduate School of Dentistry, Osaka University, 1-8 Yamadaoka, Suita, Osaka, 565-0871 (Japan)]. E-mail: yhiroko@dent.osaka-u.ac.jp; Nomachi, M. [Graduate School of Science, Osaka University, Toyonaka, Osaka, 560-0043 (Japan); Yasuda, K. [Wakasa Wan Energy Research Center, Tsuruga, Fukui, 914-0192 (Japan); Iwami, Y. [Department of Restorative Dentistry and Endodontology, Graduate School of Dentistry, Osaka University, 1-8 Yamadaoka, Suita, Osaka, 565-0871 (Japan); Ebisu, S. [Department of Restorative Dentistry and Endodontology, Graduate School of Dentistry, Osaka University, 1-8 Yamadaoka, Suita, Osaka, 565-0871 (Japan); Komatsu, H. [Graduate School of Dental Medicine, Hokkaido University, Sapporo, Hokkaido, 060-8585 (Japan); Sakai, T. [Advanced Radiation Technology Center, JAERI, Takasaki, Gunma, 370-1292 (Japan); Kamiya, T. [Advanced Radiation Technology Center, JAERI, Takasaki, Gunma, 370-1292 (Japan)

2007-07-15

Using the proton induced gamma-ray emission (PIGE) method (TIARA, Japan), we have studied fluorine (F) distribution in the human tooth under various conditions. Here, we report F uptake into the human tooth from a thin layer of F-releasing low viscous resin (FLVR). Crowns of human teeth were horizontally cut and the dentin of the cut surface was first covered with four kinds of FLVR (FL-Bond, Reactmer Bond, Xeno Bond, and Protect Liner F; thickness, 50-150 {mu}m) according to the manufacturers' instructions. Non-F-releasing and F-releasing filling resins were also hardened, on the cut surfaces of crowns covered with four kinds of FLVR thin layers. The type of the non-F-releasing filling materials used was LITE FIL IIP: G1-A (FL-Bond and LITE FIL IIP), G2-A (Reactmer Bond and LITE FIL IIP), G3-A (Xeno Bond and LITE FIL IIP), and G4-A (Protect Liner F and LITE FIL IIP). The types of F-releasing filling materials used were G1-B (FL-Bond and Beautifil), G2-B (Reactmer Bond and Reactmer Paste), G3-B (Xeno Bond and Xeno CF Paste), and G4-B (Protect Liner F and Teethmate F-1). Treatment and measurements of specimens were the same as previously reported [H. Yamamoto, M. Nomahci, K. Yasuda, Y. Iwami, S. Ebisu, N. Yamamoto, T. Sakai, T. Kamiya, Nucl. Instr. and Meth. B 210 (2003) 388]. F uptake from specimens following one month of application was estimated from 2-D maps. F penetration was observed in all teeth of G1-A-G4-A groups. The maximum values of F concentration in each tooth and F penetration depth were larger for larger F concentrations in FLVR. FLVR was useful for the F uptake into the tooth, and the F distribution near the thin layer of FLVR depended on the materials used. Between G1-A and G1-B or G4-A and G4-B, the F uptake was significantly different. We were able to obtain fundamental data, which were useful for the analysis of F transportation relating to prevention of caries.

Heavy metal ion uptake properties of polystyrene-supported ...

Indian Academy of Sciences (India)

Unknown

concentration on the uptake of metal ions have been studied. The uptake ... employed for the removal of heavy metal pollutants from industrial waste water. ... nitrate, mercuric chloride, cadmium nitrate and potassium dichromate salts. ... polymer resin was determined by reacting 50, 100, 150, 200, 250 and 300 ppm of metal.