WorldWideScience

Sample records for term selenium yeast

  1. Enteral yeast-selenium supplementation in preterm infants

    OpenAIRE

    Bogye, G.; Alfthan, G.; Machay, T.; Zubovics, L.

    1998-01-01

    AIM—To study the bioavailability of selenium enriched yeast in preterm infants living in a low selenium area (Hungary).
METHODS—Thirty six preterm infants were randomly assigned to two groups at birth with respect to selenium supplementation. In the supplemented group (n=18) infants received 4.8 mg of selenium enriched yeast containing 5 µg selenium daily.
RESULTS—In the supplemented group the serum selenium concentration increased from 36.1(±12.8) µg/l to 43.5 (7.9) µg/l and in t...

  2. Long-term selenium supplementation of humans: selenium status and relationships between selenium concentrations in skeletal muscle and indicator materials.

    Science.gov (United States)

    Behne, Dietrich; Alber, Dorothea; Kyriakopoulos, Antonios

    2010-04-01

    Supplementation with elevated doses of l-selenomethionine (SeM) or selenium-enriched yeast that contains SeM as the main selenium species is frequently used as a protective or therapeutic measure. Information on the effects of long-term selenium supplementation on the body selenium status is, however, rather scarce. We therefore investigated fifteen male test persons who had taken selenium yeast and/or SeM supplements in medium doses of 62.5-125 microg Se/day or high doses of 200-262.5 microg Se/day for periods ranging from 1 year to 24 years. Seven non-supplemented men served as controls. As skeletal muscle is the main selenium pool, thigh muscle biopsy samples were taken. The selenium concentrations in these biopsies and in samples of the indicator materials blood, blood plasma, blood cells, head hair and toenails were determined by neutron activation analysis. Compared with the controls, the muscle selenium level was raised with additional selenium supplementation, but the relative increase in the mean muscle selenium concentration (by factors of about 1.6 and 2 for the medium and high doses, respectively) was lower than that in the selenium intake. Highly significant correlations found between the selenium concentrations in muscle and whole blood (R=0.90), red blood cells (R=0.91), blood plasma (R=0.87), head hair (R=0.89) and toenails (R=0.85) show that in humans supplemented in this way the selenium status can be assessed in a relatively easy way by analysis of the selenium retention in these indicator materials. 2009 Elsevier GmbH. All rights reserved.

  3. Genotoxicity studies on Sel-Plex, a standardized, registered high-selenium yeast.

    Science.gov (United States)

    Griffiths, James C; Matulka, Ray A; Power, Ronan

    2006-01-01

    Selenium, recognized as an essential nutrient for human health, is a component of proteins and enzymes required for various biological functions and is currently being used as a feed supplement for livestock in geographical areas that are naturally low in selenium. Selenium is structurally similar to sulfur, replacing the sulfur atom in stoichiometric amounts and thus functions through an association with proteins, termed selenoproteins. In geographic areas low in selenium, there is the potential for animals (including humans) to become selenium deficient and this potential deficiency can be remedied by consumption of exogenous selenium, including selenium-enriched yeast (Saccharomyces cerevisiae) that contains high levels of organic selenium (e.g., selenized yeast). A unique, standardized, registered high selenium food-grade baker's yeast (S. cerevisiae; Sel-Plex), was tested in the following battery of Genotoxicity assays; (1) a bacterial reverse mutation test (Ames test); (2) an in vitro mammalian chromosome aberration test; and (3) a mouse micronucleus test. Under the conditions of this assay, Sel-Plex showed no evidence of mutagenic activity in Salmonella typhimurium, in the bacterial reverse mutation test. Sel-Plex did not induce significant chromosomal aberrations in cultured human lymphocytes in the in vitro mammalian chromosome aberration test. Sel-Plex did not statistically increase the frequency or proportion of micronucleated immature erythrocytes in the mouse micronucleus test. Thus, from the studies presented here, the authors conclude that Sel-Plex is nongenotoxic.

  4. DNA damage and oxidative stress response to selenium yeast in the non-smoking individuals: a short-term supplementation trial with respect to GPX1 and SEPP1 polymorphism.

    Science.gov (United States)

    Jablonska, E; Raimondi, S; Gromadzinska, J; Reszka, E; Wieczorek, E; Krol, M B; Smok-Pieniazek, A; Nocun, M; Stepnik, M; Socha, K; Borawska, M H; Wasowicz, W

    2016-12-01

    Selenium, both essential and toxic element, is considered to protect against cancer, though human supplementation trials have generated many inconsistent data. Genetic background may partially explain a great variability of the studies related to selenium and human health. The aim of this study was to assess whether functional polymorphisms within two selenoprotein-encoding genes modify the response to selenium at the level of oxidative stress, DNA damage, and mRNA expression, especially in the individuals with a relatively low selenium status. The trial involved 95 non-smoking individuals, stratified according to GPX1 rs1050450 and SEPP1 rs3877899 genotypes, and supplemented with selenium yeast (200 µg) for 6 weeks. Blood was collected at four time points, including 4 weeks of washout. After genotype stratification, the effect of GPX1 rs1050450 on lower GPx1 activity responsiveness was confirmed; however, in terms of DNA damage, we failed to indicate that individuals homozygous for variant allele may especially benefit from the increased selenium intake. Surprisingly, considering gene and time interaction, GPX1 polymorphism was observed to modify the level of DNA strand breaks during washout, showing a significant increase in GPX1 wild-type homozygotes. Regardless of the genotype, selenium supplementation was associated with a selectively suppressed selenoprotein mRNA expression and inconsistent changes in oxidative stress response, indicating for overlapped, antioxidant, and prooxidant effects. Intriguingly, DNA damage was not influenced by supplementation, but it was significantly increased during washout. These results point to an unclear relationship between selenium, genotype, and DNA damage.

  5. Effects of Selenium Yeast on Blood Glucose and Antioxidant ...

    African Journals Online (AJOL)

    olayemitoyin

    Selenium yeast is a recognised source of organic nutrient from selenium and naturally present in various food types such as Brazil nuts, chicken, fish, turkey, .... experimental period (Kolawole et al., 2012) with slight modification. Determination of Blood Glucose Level. Blood samples (5mls) were collected by cutting the tail.

  6. Bioavailability of selenium from fish, yeast and selenate: A comparative study in humans using stable isotopes

    NARCIS (Netherlands)

    Fox, T.E.; Heuvel, E.G.H.M. van den; Atherton, C.A.; Dainty, J.R.; Lewis, D.J.; Langford, N.J.; Crews, H.M.; Luten, J.B.; Lorentzen, M.; Sieling, F.W.; Aken-Schneyder, P. van; Hoek, M.; Kotterman, M.J.J.; Dael, P. van; Firweather-Tail, S.J.

    2004-01-01

    Objective: To measure the bioavailability of selenium from cooked and raw fish in humans by estimating and comparing apparent absorption and retention of selenium in biosynthetically labelled fish with labelled selenate and biosynthetically labelled selenium in brewers yeast. Design: The

  7. Bioavailibility of selenium from fish, yeast and selenate: a comparative study in humans using stable isotopes

    NARCIS (Netherlands)

    Fox, T.E.; Heuvel, van den E.G.H.M.; Atherton, C.A.; Luten, J.B.; Hoek-van Nieuwenhuizen, van M.; Kotterman, M.J.J.

    2004-01-01

    Objective: To measure the bioavailability of selenium from cooked and raw fish in humans by estimating and comparing apparent absorption and retention of selenium in biosynthetically labelled fish with labelled selenate and biosynthetically labelled selenium in brewers yeast. Design: The

  8. Speciation and bioavailability of selenium in yeast-based intervention agents used in cancer chemoprevention studies

    DEFF Research Database (Denmark)

    Larsen, Erik Huusfeldt; Hansen, Marianne; Paulin, H.

    2004-01-01

    This study investigated the speciation and bioavailability of selenium in yeast-based intervention agents from multiple manufacturers from several time points. Sources of selenized yeast included Nutrition 21 (San Diego, CA), which supplied the Nutritional Prevention of Cancer (NPC) Trial from 1981......-1996; Cypress Systems (Fresno, CA; 1997-1999); and Pharma Nord (Vejle, Denmark; 1999-2000), which supplied the Prevention of Cancer by Intervention by Selenium (PRECISE) Trial pilot studies. The low-molecular-selenium species were liberated from the samples by proteolytic hydrolysis followed by separation...... at 54-60% of the total selenium in the yeasts. One batch of yeast, however (from 1985), which originated from the same producer as the yeast used in the NPC tablets, contained only 27% of selenium in the sample as selenomethionine. Human subjects receiving 200 mug selenium/day in the UK PRECISE Pilot...

  9. Binding and Conversion of Selenium in Candida utilis ATCC 9950 Yeasts in Bioreactor Culture.

    Science.gov (United States)

    Kieliszek, Marek; Błażejak, Stanisław; Kurek, Eliza

    2017-02-25

    Selenium is considered an essential component of all living organisms. The use of yeasts as a selenium supplement in human nutrition has gained much interest over the last decade. The accumulation and biochemical transformation of selenium in yeast cells is particularly interesting to many researchers. In this article, we present the results of the determination of selenium and selenomethionine content in the biomass of feed yeast Candida utilis ATCC 9950 obtained from the culture grown in a bioreactor. The results indicated that C. utilis cells performed the biotransformation of inorganic selenium(IV) to organic derivatives (e.g., selenomethionine). Selenium introduced (20-30 mg Se(4+)∙L(-1)) to the experimental media in the form of sodium(IV) selenite (Na₂SeO₃) salt caused a significant increase in selenium content in the biomass of C. utilis,irrespective of the concentration. The highest amount of selenium (1841 μg∙gd.w.(-1)) was obtained after a 48-h culture in media containing 30 mg Se(4+)∙L(-1). The highest content of selenomethionine (238.8 μg∙gd.w.(-1)) was found after 48-h culture from the experimental medium that was supplemented with selenium at a concentration of 20 mg Se(4+)∙L(-1). Biomass cell in the cultures supplemented with selenium ranged from 1.5 to 14.1 g∙L(-1). The results of this study indicate that yeast cell biomass of C. utilis enriched mainly with the organic forms of selenium can be a valuable source of protein. It creates the possibility of obtaining selenium biocomplexes that can be used in the production of protein-selenium dietary supplements for animals and humans.

  10. Organic selenium supplementation increases mercury excretion and decreases oxidative damage in long-term mercury-exposed residents from Wanshan, China.

    Science.gov (United States)

    Li, Yu-Feng; Dong, Zeqin; Chen, Chunying; Li, Bai; Gao, Yuxi; Qu, Liya; Wang, Tianchen; Fu, Xin; Zhao, Yuliang; Chai, Zhifang

    2012-10-16

    Due to a long history of extensive mercury mining and smelting activities, local residents in Wanshan, China, are suffering from elevated mercury exposure. The objective of the present study was to study the effects of oral supplementation with selenium-enriched yeast in these long-term mercury-exposed populations. One hundred and three volunteers from Wanshan area were recruited and 53 of them were supplemented with 100 μg of organic selenium daily as selenium-enriched yeast while 50 of them were supplemented with the nonselenium-enriched yeast for 3 months. The effects of selenium supplementation on urinary mercury, selenium, and oxidative stress-related biomarkers including malondialdehyde and 8-hydroxy-2-deoxyguanosine were assessed. This 3-month selenium supplementation trial indicated that organic selenium supplementation could increase mercury excretion and decrease urinary malondialdehyde and 8-hydroxy-2-deoxyguanosine levels in local residents.

  11. Long-Term Dietary Supplementation with Selenium-Enriched Yeast Improves Cognitive Impairment, Reverses Synaptic Deficits, and Mitigates Tau Pathology in a Triple Transgenic Mouse Model of Alzheimer's Disease.

    Science.gov (United States)

    Zhang, Zhong-Hao; Wen, Lei; Wu, Qiu-Yan; Chen, Chen; Zheng, Rui; Liu, Qiong; Ni, Jia-Zuan; Song, Guo-Li

    2017-06-21

    Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by multiple histopathological changes in the brain and by impairments in memory and cognitive function. Currently, there is no effective treatment that can halt or reverse the progression of this disease. Here, we explored the effects of 3 months of treatment with selenium-enriched yeast (Se-yeast), which is commonly used as a source of organic selenium (Se) for nutrition, on cognitive dysfunction and neuropathology in the triple transgenic mouse model of AD (3×Tg-AD mice). As the results revealed that Se-yeast significantly improved the spatial learning and memory retention of 3×Tg-AD mice, promoted neuronal activity, attenuated the activation of astrocytes and microglia, mitigated synaptic deficits, and reduced the levels of total tau and phosphorylated tau though inhibiting the activity of GSK-3β, dietary supplementation with Se-yeast exerted multiple beneficial effects on the prevention or treatment of AD. These findings provide evidence of a potentially viable compound for AD treatment.

  12. Bioavailability of selenium from fish, yeast and selenate: a comparative study in humans using stable isotopes.

    Science.gov (United States)

    Fox, T E; Van den Heuvel, E G H M; Atherton, C A; Dainty, J R; Lewis, D J; Langford, N J; Crews, H M; Luten, J B; Lorentzen, M; Sieling, F W; van Aken-Schneyder, P; Hoek, M; Kotterman, M J J; van Dael, P; Fairweather-Tait, S J

    2004-02-01

    To measure the bioavailability of selenium from cooked and raw fish in humans by estimating and comparing apparent absorption and retention of selenium in biosynthetically labelled fish with labelled selenate and biosynthetically labelled selenium in brewers yeast. The intervention study was a parallel, randomised, reference substance controlled design carried out at two different centres in Europe. The human study was carried out at the Institute of Food Research, Norwich, UK and at TNO Nutrition and Food Research, Zeist, The Netherlands. In all, 35 male volunteers aged 18-50 y were recruited; 17 subjects were studied in Norwich (UK) and 18 in Zeist (Netherlands). All of the recruited subjects completed the study. Biosynthetically labelled trout fish (processed by two different methods), biosynthetically labelled brewers yeast and isotopically labelled selenate were used to estimate selenium apparent absorption and retention by quantitative analysis of stable isotope labels recovered in faeces and urine. Subjects consumed the labelled foods in four meals over two consecutive days and absorption was measured by the luminal disappearance method over 10 days. Urinary clearance of isotopic labels was measured over 7 days to enable retention to be calculated. Apparent absorption of selenium from fish was similar to selenate and there was no difference between the two processing methods used. However, retention of fish selenium was significantly higher than selenate (P<0.001). Apparent absorption and retention of yeast selenium was significantly different (P<0.001) from both fish selenium and selenate. Fish selenium is a highly bioavailable source of dietary selenium. Cooking did not affect selenium apparent absorption or retention from fish. Selenium from yeast is less bioavailable.

  13. Selenium deficiency, reversible cardiomyopathy and short-term intravenous feeding.

    OpenAIRE

    Levy, J. B.; Jones, H. W.; Gordon, A. C.

    1994-01-01

    We report the case of a patient with Crohn's disease receiving short-term postoperative parenteral nutrition supplemented with trace elements who nevertheless became selenium deficient with evidence of a cardiomyopathy. This was fully reversible with oral selenium supplementation. Current parenteral feeding regimes may not contain enough selenium for malnourished patients.

  14. Targeted sulphur and selenium speciation in yeast by parallel elemental and molecular mass spectrometry

    DEFF Research Database (Denmark)

    Hillestrøm, Peter René; Mapelli, Valeria; Olsson, Lisbeth

    Selenium supplement, often selenized yeast, are currently the subject of intense study owing to their potential preventive effects against cancer. However, fundamental knowledge of the yeast’s metabolism is required for metabolic engineering biosynthetic production of potent Se-species. A method...

  15. Acute and subchronic toxicity studies on Sel-Plex, a standardized, registered high-selenium yeast.

    Science.gov (United States)

    Griffiths, James C; Matulka, Ray A; Power, Ronan

    2006-01-01

    Selenium has been recognized as an essential nutrient for human health; however, its bioavailability is primarily dependent upon the type of selenium, elemental versus organic. In geographic areas low in selenium, there is the potential for animals (including humans) to become selenium deficient and this potential deficiency can be remedied by consumption of exogenous selenium, including selenium-enriched yeast (Saccharomyces cerevisiae) that contains high levels of organic selenium (e.g., selenized yeast). The present studies were conducted to investigate potential oral toxicity of a unique selenized yeast preparation (Sel-Plex) when administered to (1) adult female CHS Swiss mice ICo:OFI (IOPS Caw); (2) adult female CHS Sprague-Dawley rats; and (3) adult male and female Sprague-Dawley CD rats. For the 28- and 90-day toxicity studies, (1) adult male and female Sprague-Dawley CRL:CD(R)(SD) IGS BR strain rats and (2) adult male and female 6- to 7-month-old Beagle dogs were used. The LD50 for mice was >or=2000 mg Sel-Plex/kg (>or=4.06 mg Se/kg) and for rats, was greater than >or=2000 mg Sel-Plex/kg (>or=4.06 mg Se/kg). In the two 28-day studies, for rats, the no observed adverse effects level (NOAEL) was 50 mg Sel-Plex/kg/day (0.1 mg Se/kg/day), and for the dogs, the NOAEL was 22.5 mg Sel-Plex/kg/day (0.045 mg Se/kg/day). For the two 90-day studies, for rats the NOAEL for Sel-Plex was 114 mg/kg/day (0.23 mg Se/kg/day), and for dogs, the NOAEL was 30 mg Sel-Plex/kg/day (0.06 mg Se/kg/day): the latter being the NOAEL in the most sensitive species.

  16. Effects of Selenium on Morphological Changes in Candida utilis ATCC 9950 Yeast Cells.

    Science.gov (United States)

    Kieliszek, Marek; Błażejak, Stanisław; Bzducha-Wróbel, Anna; Kurcz, Agnieszka

    2016-02-01

    This paper presents the results of microscopic examinations of the yeast cells cultured in yeast extract-peptone-dextrose (YPD) media supplemented with sodium selenite(IV). The analysis of the morphological changes in yeast cells aimed to determine whether the selected selenium doses and culturing time may affect this element accumulation in yeast cell structures in a form of inorganic or organic compounds, as a result of detoxification processes. The range of characteristic morphological changes in yeasts cultivated in experimental media with sodium selenite(IV) was observed, including cell shrinkage and cytoplasm thickening of the changes within vacuole structure. The processes of vacuole disintegration were observed in aging yeast cells in culturing medium, which may indicate the presence of so-called ghost cells lacking intracellular organelles The changes occurring in the morphology of yeasts cultured in media supplemented with sodium selenite were typical for stationary phase of yeast growth. From detailed microscopic observations, larger surface area of the cell (6.03 μm(2)) and yeast vacuole (2.17 μm(2)) were noticed after 24-h culturing in the medium with selenium of 20 mg Se(4+)/L. The coefficient of shape of the yeast cells cultured in media enriched with sodium selenite as well as in the control YPD medium ranged from 1.02 to 1.22. Elongation of cultivation time (up to 48 and 72 h) in the media supplemented with sodium selenite caused a reduction in the surface area of the yeast cell and vacuole due to detoxification processes.

  17. Effect of sodium selenite and selenium yeast on performance, egg quality, antioxidant capacity, and selenium deposition of laying hens.

    Science.gov (United States)

    Han, X J; Qin, P; Li, W X; Ma, Q G; Ji, C; Zhang, J Y; Zhao, L H

    2017-09-01

    This study compared the effects of sodium selenite and selenium yeast and their combination on laying performance, egg quality, antioxidant capacity, and selenium (Se) contents in tissues and eggs. Two-hundred-eighty-eight Jing Hong layers that were similar in laying rate (87.5 ± 0.38%) and body weight (1.70 ± 0.02 kg) were randomly distributed into 4 treatments for 11 wk (from 203 d old to 279 d old) with 9 replicates of 8 hens per replicate. The diets (corn-soybean meal diet) were supplemented with 0 [blank control (BC)], 0.3 mg/kg Se from sodium selenite (SS), 0.15 mg/kg Se from sodium selenite and 0.15 mg/kg Se from Se yeast (SS+SY), or 0.3 mg/kg Se from Se yeast (SY). Results showed that the laying rate of the SS+SY group increased significantly (P 0.05) in egg quality between the Se-supplemented diets and the BC diet. The serum glutathione peroxidase (GSH-Px) activity was increased (P < 0.01) in hens fed Se-supplemented diets compared to the BC diet. The liver superoxide dismutase (SOD) activity of the SY group was increased significantly (P < 0.05) compared to the BC group. Significant increase (P < 0.01) due to SY supplementation was noted in the serum vitamin E content compared to BC and SS. Layers fed Se-supplemented diets had higher (P < 0.01) contents of Se in the serum, liver, and kidney compared to the BC diet. Compared to BC, Se content in eggs was significantly increased (P < 0.05) by feeding supplementary Se. In conclusion, the effects of SS and Se yeast were approximately equal in promoting antioxidant capacity of laying hens, while Se yeast is easier to deposit into eggs and tissues. The diet with added equal amounts of the 2 sources of Se was more cost effective and affordable than a comparable amount of Se yeast to obtain the promising production performance and nearly similar Se deposition. © 2017 Poultry Science Association Inc.

  18. Prostatic response to supranutritional selenium supplementation: comparison of the target tissue potency of selenomethionine vs. selenium-yeast on markers of prostatic homeostasis.

    Science.gov (United States)

    Waters, David J; Shen, Shuren; Kengeri, Seema S; Chiang, Emily C; Combs, Gerald F; Morris, J Steven; Bostwick, David G

    2012-11-06

    Prostate cancer is the product of dysregulated homeostasis within the aging prostate. Supplementation with selenium in the form of selenized yeast (Se-yeast) significantly reduced prostate cancer incidence in the Nutritional Prevention of Cancer Trial. Conversely, the Selenium and Vitamin E Cancer Prevention Trial (SELECT) showed no such cancer-protective advantage using selenomethionine (SeMet). The possibility that SeMet and Se-yeast are not equipotent in promoting homeostasis and cancer risk reduction in the aging prostate has not been adequately investigated; no direct comparison has ever been reported in man or animals. Here, we analyzed data on prostatic responses to SeMet or Se-yeast from a controlled feeding trial of 49 elderly beagle dogs-the only non-human species to frequently develop prostate cancer during aging-randomized to one of five groups: control; low-dose SeMet, low-dose Se-yeast (3 μg/kg); high-dose SeMet, high-dose Se-yeast (6 μg/kg). After seven months of supplementation, we found no significant selenium form-dependent differences in toenail or intraprostatic selenium concentration. Next, we determined whether SeMet or Se-yeast acts with different potency on six markers of prostatic homeostasis that likely contribute to prostate cancer risk reduction-intraprostatic dihydrotestosterone (DHT), testosterone (T), DHT:T, and epithelial cell DNA damage, proliferation, and apoptosis. By analyzing dogs supplemented with SeMet or Se-yeast that achieved equivalent intraprostatic selenium concentration after supplementation, we showed no significant differences in potency of either selenium form on any of the six parameters over three different ranges of target tissue selenium concentration. Our findings, which represent the first direct comparison of SeMet and Se-yeast on a suite of readouts in the aging prostate that reflect flux through multiple gene networks, do not further support the notion that the null results of SELECT are attributable to

  19. Prostatic Response to Supranutritional Selenium Supplementation: Comparison of the Target Tissue Potency of Selenomethionine vs. Selenium-Yeast on Markers of Prostatic Homeostasis

    Science.gov (United States)

    Waters, David J.; Shen, Shuren; Kengeri, Seema S.; Chiang, Emily C.; Combs, Gerald F.; Morris, J. Steven; Bostwick, David G.

    2012-01-01

    Prostate cancer is the product of dysregulated homeostasis within the aging prostate. Supplementation with selenium in the form of selenized yeast (Se-yeast) significantly reduced prostate cancer incidence in the Nutritional Prevention of Cancer Trial. Conversely, the Selenium and Vitamin E Cancer Prevention Trial (SELECT) showed no such cancer-protective advantage using selenomethionine (SeMet). The possibility that SeMet and Se-yeast are not equipotent in promoting homeostasis and cancer risk reduction in the aging prostate has not been adequately investigated; no direct comparison has ever been reported in man or animals. Here, we analyzed data on prostatic responses to SeMet or Se-yeast from a controlled feeding trial of 49 elderly beagle dogs—the only non-human species to frequently develop prostate cancer during aging—randomized to one of five groups: control; low-dose SeMet, low-dose Se-yeast (3 μg/kg); high-dose SeMet, high-dose Se-yeast (6 μg/kg). After seven months of supplementation, we found no significant selenium form-dependent differences in toenail or intraprostatic selenium concentration. Next, we determined whether SeMet or Se-yeast acts with different potency on six markers of prostatic homeostasis that likely contribute to prostate cancer risk reduction—intraprostatic dihydrotestosterone (DHT), testosterone (T), DHT:T, and epithelial cell DNA damage, proliferation, and apoptosis. By analyzing dogs supplemented with SeMet or Se-yeast that achieved equivalent intraprostatic selenium concentration after supplementation, we showed no significant differences in potency of either selenium form on any of the six parameters over three different ranges of target tissue selenium concentration. Our findings, which represent the first direct comparison of SeMet and Se-yeast on a suite of readouts in the aging prostate that reflect flux through multiple gene networks, do not further support the notion that the null results of SELECT are attributable

  20. Effects of selenium supplementation as sodium selenite or selenized yeast and different amounts of vitamin E on selenium and vitamin E status of broilers

    OpenAIRE

    Marković Radmila; Jovanović B.I.; Baltić Ž.M.; Šefer D.; Petrujkić B.; Sinovec Z.

    2008-01-01

    The aim of this experiment was to determine the effects of broiler meal supplementation with different forms of selenium (as Na-selenite or selenized yeast) and different amounts of vitamin E on selenium and vitamin E status in broiler tissues. A total number of 240 broilers (Cobb 500) were divided in four experimental groups supplemented with Se and vitamin E for a period of 42 days: group SS+E20 - 0.3 mg/kg sodium selenite and 20 IU of vitamin E; group SY+E20 - 0.3 mg/kg selenized yeast and...

  1. Dietary supplementation with selenium yeast and tea polyphenols improve growth performance and nitrite tolerance of Wuchang bream (Megalobrama amblycephala).

    Science.gov (United States)

    Long, Meng; Lin, Wang; Hou, Jie; Guo, Honghui; Li, Li; Li, Dapeng; Tang, Rong; Yang, Fan

    2017-09-01

    In order to explore the effects of dietary selenium yeast, tea polyphenols and their combination on growth of Wuchang bream (Megalobrama amblycephala) and its resistance to nitrite stress, 360 healthy Wuchang bream with initial body weight of (55.90 ± 2.60) g were randomly divided into four groups: a control group fed with basal diet and three treated groups fed with basal diets supplemented with 0.50 mg/kg selenium yeast, 50 mg/kg tea polyphenols, and the combination of 0.50 mg/kg selenium yeast and 50 mg/kg tea polyphenols, respectively. After 60 d of feeding, the growth performance of Wuchang bream was measured. Then 25 fish per tank were exposed to nitrite stress of 15.0 mg/L. The serum stress hormones, liver histology and hepatic antioxidant responses were evaluated before nitrite exposure (0 h) and at 6, 12, 24, 48 and 96 h after exposure. The results showed that before nitrite exposure, compared with the control, the weight gain, specific growth rate, liver total antioxidant capacity, the activities and transcriptional levels of hepatic antioxidant enzymes (superoxide dismutase and glutathione peroxidase) in the selenium yeast and combination groups were significantly increased, while feed conversion rate was decreased significantly, which suggested that the combined use of selenium yeast and tea polyphenols as well as the single selenium yeast supplementation improved growth performance and enhanced antioxidant capacity in fish. After nitrite exposure, compared with the control, liver total antioxidant capacity as well as the activities and transcription levels of catalase superoxide dismutase and glutathione peroxidase in three treatment groups were significantly increased in varying degrees whereas serum cortisol contents and liver malondialdehyde levels were decreased significantly. By contrast, the combined use of selenium yeast and tea polyphenols was more effective than the single supplementation with selenium yeast or tea polyphenols. In

  2. Effect of dietary selenium yeast supplementation on porcine circovirus type 2 (PCV2 infections in mice.

    Directory of Open Access Journals (Sweden)

    Gang Liu

    Full Text Available The present study was performed to determine the protective role of dietary selenium (Se yeast supplementation in porcine circovirus type 2 (PCV2 infected mice. Forty-eight Kun Ming female mice were randomly assigned to Se yeast group (0.3%Se +basal diet, n = 24 and control group (basal diet, n = 24. After 3 days of adaptive feeding and 15 days treatment with the experimental feed, mice were challenged by intraperitioneal injection of PCV2 at the dosage of 2000 TCID50 (50% tissue culture infection dose, TCID50. Serum total superoxide dismutase (SOD activity, malondialdehyde (MDA level, tumor necrosis factor alpha (TNF-α, C-reactive protein (CRP and interleukin-1 beta (IL-1β levels were measured at 5, 10, 15, 20 days post infection (dpi. The PCV2 virus load in the liver, spleen and lung, and the microscopic lesions in the liver, spleen and lung also were determined on 5, 10, 15, and 20 dpi. Dietary Se yeast supplementation decreased (Pμ0.05 the serum levels of TNF-α, but had no significant effect on the activity of SOD and the levels of MDA, CRP and IL-1β between experimental and control groups. Dietary Se yeast supplementation had little effect on the PCV2 virus load in the liver, spleen and lung. However, mice in the selenium yeast group showed a significant decrease in microscopic lesion scores in the lung and spleen compared with those in the control group (Pμ0.05. These data indicate Se yeast attenuated the PCV2 infection through altering the systemic inflammation and maintaining the normal organ morphology.

  3. Selenium

    Science.gov (United States)

    Stillings, Lisa L.; Schulz, Klaus J.; DeYoung, John H.; Seal, Robert R.; Bradley, Dwight C.

    2017-12-19

    Selenium (Se) was discovered in 1817 in pyrite from copper mines in Sweden. It is a trace element in Earth’s crust, with an abundance of three to seven orders of magnitude less than the major rock-forming elements. Commercial use of selenium began in the United States in 1910, when it was used as a pigment for paints, ceramic glazes, and red glass. Since that time, it has had many other economic uses—notably, in the 1930s and 1940s, when it was used in rectifiers (which change alternating current to direct current), and in the 1960s, when it began to be used in the liner of photocopier drums. In the 21st century, other compounds have replaced selenium in these older products; modern uses for selenium include energy-efficient windows that limit heat transfer and thin-film photovoltaic cells that convert solar energy into electricity.In Earth’s crust, selenium is found as selenide minerals, selenate and selenite salts, and as substitution for sulfur in sulfide minerals. It is the sulfide minerals, most commonly those in porphyry copper deposits, that provide the bulk of the selenium produced for the international commodity market. Selenium is obtained as a byproduct of copper refining and recovered from the anode slimes generated in electrolytic production of copper. Because of this, the countries that have the largest resources and (or) reserves of copper also have the largest resources and (or) reserves of selenium.Because selenium occurs naturally in Earth’s crust, its presence in air, water, and soil results from both geologic reactions and human activity. Selenium is found concentrated naturally in soils that overlie bedrock with high selenium concentrations. Selenium mining, processing, use in industrial and agricultural applications, and disposal may all contribute selenium to the environment. A well-known case of selenium contamination from agricultural practices was discovered in 1983 in the Kesterson National Wildlife Refuge in California. There

  4. Determination of total selenium in nutritional supplements and selenised yeast by Zeeman-effect graphite furnace atomic absorption spectrometry

    DEFF Research Database (Denmark)

    Larsen, Erik Huusfeldt; Ekelund, J.

    1989-01-01

    A method for the determination of total selenium in nutritional supplements and selenised yeast is described. The samples were ashed in nitric acid. Hydrochloric acid was used to prevent precipitation of, in particular, iron salts. After appropriate dilutions, the selenium was determined by Zeeman......-effect background corrected graphite furnace atomic absorption spectrometry. A furnace ashing step at 1100 °C was necessary in order to obtain a total recovery of selenium when present in the organic form. Palladium nitrate-magnesium nitrate was used as a matrix modifier. Independent methods were used to determine...

  5. Spectrophotometric evaluation of selenium binding by Saccharomyces cerevisiae ATCC MYA-2200 and Candida utilis ATCC 9950 yeast.

    Science.gov (United States)

    Kieliszek, Marek; Błażejak, Stanisław; Płaczek, Maciej

    2016-05-01

    In this study, the ability of selenium binding the biomas of Saccharomyces cerevisiae ATCC MYA-2200 and Candida utilis ATCC 9950 was investigated. Sodium selenite(IV) salts were added to the experimental media at concentrations of 10, 20, 40, and 60 mg Se(4+) L(-1). In the tested concentration range, one concentration reported a significant reduction in the biomass yield of both yeast strains. Intense growth was observed for C. utilis yeast, which reached the highest biomass yield of 15 gd.w.L(-1) after 24h cultivation in the presence of 10mg Se(4+) L(-1). Based on the use of spectrophotometric method for the determination of selenium content by using Variamine Blue as a chromogenic agent, efficient accumulation of this element in the biomass of the investigated yeast was observed. The highest amount of selenium, that is, 5.64 mg Se(4+)gd.w.(-1), was bound from the environment by S. cerevisiae ATCC MYA-2200 cultured in the presence of 60 mg Se(4+) L(-1) medium 72h Slightly less amount, 5.47 mg Se(4+) gd.w.(-1), was absorbed by C. utilis ATCC 9950 during similar cultural conditions. Based on the results of the biomass yield and the use of selenium from the medium, it can be observed that yeasts of the genus Candida are more efficient in binding this element, and this property finds practical application in the production of selenium-enriched yeast. Copyright © 2016 Elsevier GmbH. All rights reserved.

  6. Effects of Selenium Yeast on Blood Glucose and Antioxidant Biomarkers in Cholesterol Fed Diet Induced Type 2 Diabetes Mellitus in Wistar Rats.

    Science.gov (United States)

    Tanko, Y; Jimoh, A; Ahmed, A; Adam, A; Ejeh, L; Mohammed, A; Ayo, J O

    2017-03-06

    Selenium is an antioxidant that prevents oxygen radical from damaging cells from chronic diseases that can develop from cell injury and inflammation such as diabetes mellitus. The aim of the study is to investigate the possible protective effect of selenium yeast on cholesterol diet induced type-2 diabetes mellitus and oxidative stress in rats. Twenty male wistar rats were divided in to four groups of five animals each: Group 1: (Negative control) received standard animal feed only, Group 2:  received cholesterol diet (CD) only, Group 3: received CD and 0.1 mg/kg selenium yeast orally, Group 4: Received CD and 0.2 mg/kg selenium yeast orally for six weeks. At the end of the study period, the animals were sacrificed and the serum samples were collected and evaluated for estimation of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). The results showed a significant decrease in blood glucose level in the groups  co-administered CD and selenium yeast when compared to CD group only. Antioxidant enzymes status recorded significant decrease in SOD, CAT and GPx activities in CD and selenium yeast administered when compared to CD group only. In Conclusion, Selenium yeast administrations prevent free radical formations which are potent inducer of diabetes mellitus.

  7. Influence of Selenium Content in the Culture Medium on Protein Profile of Yeast Cells Candida utilis ATCC 9950.

    Science.gov (United States)

    Kieliszek, Marek; Błażejak, Stanisław; Bzducha-Wróbel, Anna

    2015-01-01

    Selenium is an essential trace element for human health and it has been recognized as a component of several selenoproteins with crucial biological functions. It has been identified as a component of active centers of many enzymes, as well as integral part of biologically active complexes. The aim of the study was to evaluate the protein content and amino acid profile of the protein of fodder yeast Candida utilis ATCC 9950 cultured in media control and experimental enriched selenium. Protein analysis was performed using SDS-PAGE method consisting of polyacrylamide gel electrophoresis in the presence of SDS. The highest contents of soluble protein (49,5 mg/g) were found in yeast cells after 24-hour culture conducted in control (YPD) medium. In the presence of selenium there were determined small amounts of protein content. With increasing time of yeast culture (to 72 hours) the control and experimental media were reported to reduce soluble protein content. In electropherogram proteins from control cultures was observed the presence of 10 protein fractions, but in all the experimental cultures (containing 20, 30, and 40 mg/L selenium) of 14 protein fractions. On the basis of the molecular weights of proteins, it can be concluded that they were among others: selenoprotein 15 kDa and selenoprotein 18 kDa.

  8. Influence of Selenium Content in the Culture Medium on Protein Profile of Yeast Cells Candida utilis ATCC 9950

    Directory of Open Access Journals (Sweden)

    Marek Kieliszek

    2015-01-01

    Full Text Available Selenium is an essential trace element for human health and it has been recognized as a component of several selenoproteins with crucial biological functions. It has been identified as a component of active centers of many enzymes, as well as integral part of biologically active complexes. The aim of the study was to evaluate the protein content and amino acid profile of the protein of fodder yeast Candida utilis ATCC 9950 cultured in media control and experimental enriched selenium. Protein analysis was performed using SDS-PAGE method consisting of polyacrylamide gel electrophoresis in the presence of SDS. The highest contents of soluble protein (49,5 mg/g were found in yeast cells after 24-hour culture conducted in control (YPD medium. In the presence of selenium there were determined small amounts of protein content. With increasing time of yeast culture (to 72 hours the control and experimental media were reported to reduce soluble protein content. In electropherogram proteins from control cultures was observed the presence of 10 protein fractions, but in all the experimental cultures (containing 20, 30, and 40 mg/L selenium of 14 protein fractions. On the basis of the molecular weights of proteins, it can be concluded that they were among others: selenoprotein 15 kDa and selenoprotein 18 kDa.

  9. Effects of supplementation with selenium, as selenized yeast, in a healthy male population from New Zealand.

    Science.gov (United States)

    Karunasinghe, Nishi; Han, Dug Yeo; Zhu, Shuotun; Duan, He; Ko, Yi-Ju; Yu, Jie Fu; Triggs, Christopher M; Ferguson, Lynnette R

    2013-01-01

    Selenium (Se) supplementation was tested in a group of healthy men from Auckland, New Zealnd with selenized yeast (Selplex, 200 μg/day) as the supplementation mode. A set of biomarkers, including DNA damage levels and seleno-antioxidant enzyme levels, were evaluated at pre- and postsupplementation time points. Supplementation produced significant increases in serum Se levels, red blood cell (RBC) thioredoxin reductase (TR) activity and peroxide-induced DNA damage, when the mean baseline serum Se level was 110 ng/ml. Those with higher baseline serum Se levels gained less serum Se and showed a significant reduction of RBC glutathione peroxidase (GPx) activity by supplementation. The optimum benefits of supplementation on DNA stability are observed when the serum Se level reaches between >120 and supplementation, whereas those having lower baseline DNA damage are disadvantaged. A dose of 200 μg/day selenized yeast was also shown to be a safer supplementation option compared to a similar dose of selenomethionine (SeMet). This study highlights the requirement for prestratification of a population by standing serum Se level and baseline DNA damage level, before any Se supplementation is carried out.

  10. Separation of selenium compounds by CE-ICP-MS in dynamically coated capillaries applied to selenized yeast samples

    DEFF Research Database (Denmark)

    Bendahl, Lars; Gammelgaard, Bente

    2004-01-01

    The selenium species in nutritional supplement tablets, based on selenized yeast, were separated by capillary zone electrophoresis using capillaries coated dynamically with poly(vinyl sulfonate) and detected by ICP-MS. Sample pre-treatment consisted of cold-water extraction by sonication and subs......The selenium species in nutritional supplement tablets, based on selenized yeast, were separated by capillary zone electrophoresis using capillaries coated dynamically with poly(vinyl sulfonate) and detected by ICP-MS. Sample pre-treatment consisted of cold-water extraction by sonication......-water extract within 13 min. The efficiency of the system corresponded to 620 000 theoretical plates. When spiking the sample with available standards, co-migration was observed with selenomethionine and selenocystine-Se-methylselenocysteine-the latter species were not separated. When the cold-water extract...

  11. Chromium, selenium, and zinc multimineral enriched yeast supplementation ameliorates diabetes symptom in streptozocin-induced mice.

    Science.gov (United States)

    Liu, Jun; Bao, Wei; Jiang, Man; Zhang, Yan; Zhang, Xiping; Liu, Liegang

    2012-05-01

    Chromium, selenium, and zinc malnutrition has been implicated in the pathogenesis of diabetic mellitus. This study aims to investigate the effects of novel multiminerals-enriched yeast (MMEY) which are minerals supplementation containing elevated levels of chromium, selenium, and zinc simultaneously in a diabetic animal model. Streptozocin-induced diabetic male Balb/c mice (n = 80) were randomly divided into diabetes control group and three treatment groups. They were administrated oral gavages with low, medium, or high doses of MMEY, respectively. Meanwhile, healthy male Balb/c mice (n = 40) of the same body weight were randomly assigned into normal control group and high dose of MMEY control group. After 8 weeks duration of treatment, the animals were sacrificed by cervical dislocation. Serum glucose concentrations, lipid profiles, oxidative/antioxidant, and immunity status were determined. No significant adverse effects were observed in the high-dose MMEY control group. Treatment of the diabetic mice with medium- or high-dose MMEY significantly decreased serum glucose, triglyceride, total cholesterol, and malondialdehyde and increased high-density lipoprotein cholesterol, glutathione, and the activities of superoxide dismutase and glutathione peroxidase. In addition, MMEY ameliorated the pathological damage of the pancreatic islets, elevated the thymus or spleen coefficient, and increased the expressions of interleukin-2 and -4 in spleen lymphocytes compared with unsupplemented diabetic mice. In conclusion, these results indicate that supplemental MMEY inhibits hyperglycemia, abates oxidative stress, modulates disorders of lipid metabolism, and reduces the impairment of immune function in diabetic mice; especially notable are the protective effects of medium doses of MMEY on the islet cells of diabetic mice.

  12. Selenium homeostasis and induction of thioredoxin reductase during long term selenite supplementation in the rat.

    Science.gov (United States)

    Erkhembayar, Suvd; Mollbrink, Annelie; Eriksson, Malin; Larsen, Erik H; Eriksson, Lennart C

    2011-12-01

    Selenium is a candidate treatment for liver tumour prevention in chronic liver disease. In this study, we have studied selenium uptake, distribution and accumulation in rats provided with water containing tumour-preventive doses of sodium selenite for 10 weeks. Male Fischer 344 rats were given drinking water containing 1 μg/mL or 5 μg/mL sodium selenite. Selenium levels were monitored in serum and liver tissue over the 10-week period, and the kinetics of induction of the redox-active cytosolic selenoenzyme thioredoxin reductase were followed. Selenite exposure via drinking water caused a dose-dependent increase in blood and liver selenium levels, with plateaus at 6 and 8 weeks, respectively. These plateaus were reached at the same level of selenium regardless of dose, and no further accumulation was observed. A selenium-dependent increase in the activity of TrxR1 in parallel with the increase in liver selenium levels was also seen, and the induction of TrxR1 mRNA was seen only during the first three days of treatment, when the levels of selenium in the liver were increasing. Sodium selenite at 1 and 5 μg/mL did not affect body weight or relative liver mass. We concluded that long-term treatment with selenite did not cause accumulation of selenium and that the activity of TrxR1 in the liver rose with the selenium levels. We therefore suggest that sodium selenite at doses up to 5 μg/mL could be used for long-term tumour prevention. Copyright © 2011 Elsevier GmbH. All rights reserved.

  13. Detection of over 100 selenium metabolites in selenized yeast by liquid chromatography electrospray time-of-flight mass spectrometry.

    Science.gov (United States)

    Gilbert-López, Bienvenida; Dernovics, Mihaly; Moreno-González, David; Molina-Díaz, Antonio; García-Reyes, Juan F

    2017-08-15

    The characterization of the selenometabolome of Selenized(Se)-yeast, that is the fraction of water soluble low-molecular weight Se-metabolites produced in Se-yeast is of paramount interest to expand the knowledge on the composition of this food supplement. In this work, we have applied liquid chromatography electrospray time-of-flight mass spectrometry (LC-TOFMS) to search for Se-species from the low molecular weight range fraction of the selenized yeast used for food supplements. Prior to LC-TOFMS, sample treatment consisted of ultrasound assisted water extraction followed by size exclusion fractionation assisted with off-line inductively coupled plasma mass spectrometry detection of isotope (82)Se. The fraction corresponding to low-molecular weight species was subjected to LC-TOFMS using electrospray ionization in the positive ion mode. The detection of the suspected selenized species has been based on the information obtained from accurate mass measurements of both the protonated molecules and fragments from in-source CID fragmentation; along with the characteristic isotope pattern exhibited by the presence of Se. The approach enables the detection of 103 selenized species, most of them not previously reported, in the range from ca. 300-650Da. Besides the detection of selenium species, related sulphur derivate metabolites were detected based on the accurate mass shift due to the substitution of sulphur and selenium. Copyright © 2017. Published by Elsevier B.V.

  14. Effect of organic selenium-enriched yeast supplementation in finishing sheep diet on carcasses microbiological contamination and meat physical characteristics

    Directory of Open Access Journals (Sweden)

    Gisela Velázquez-Garduño

    2015-09-01

    Full Text Available The aim of the current study was to evaluate the effect of feeding Pelibuey sheep on diet supplemented with different doses of organic selenium (Se-enriched yeast on carcasses microbiological contamination and meat physical characteristics. The experiment was conducted during the finishing stage of 18 female sheep and lasted for 60 days. In a complete randomized design, sheep were distributed to one of three treatments: the control without Se-yeast (T1, the control supplemented with Se-yeast at 0.35 mg Se/kg DM (T2, and control supplemented with Se-yeast at 0.60 mg Se/kg DM (T3. The yeast product used was Selyeast 3000TM yeast (LFA Lesaffre, Toluca, Mexico with a Se concentration of 3000 ppm (mg/kg. Lambs were slaughtered at the end of the experiment at an average weight of 39.5±4.41 kg and samples were taken for microbiological analysis. There were no differences between treatments (P>0.05 and the aerobic plate counts for T1, T2 and T3 had indexes of 0.10, 0.08 and 0.08 log10 CFU/cm2, respectively. Total coliform counts obtained were 0.13, 0.10 and 0.09 log10 CFU/cm2 for T1, T2 and T3, respectively, and the faecal coliform counts were 0.09 log10 CFU/cm2 for T1, 0.06 log10 CFU/cm2 for T2 and 0.07 log10 CFU/cm2 for T3. No significant effects (P>0.05 were observed for carcasses physical characteristics of microbial growth, initial and ultimate pH and temperature, colour values and water holding capacity. It can therefore be concluded that organic Se-enriched yeast did not affect carcasses bacterial proliferation or meat physical characteristics.

  15. Supplementation of selenium-enriched yeast attenuates age-dependent transcriptional changes of heart in mitochondrial DNA mutator mice

    Directory of Open Access Journals (Sweden)

    Rijin Xiao

    2014-03-01

    Full Text Available Background: Age is a major risk factor in developing heart diseases and has been associated with profound transcriptional changes in mammalian tissues. Low tissue selenium has recently been linked to several age-related diseases, including cardiovascular disease. This study investigated the global effects of age and dietary supplementation of selenium on heart transcriptional profiles in POLG mutator mice. Methods: Heart transcription profiles from young (2-month-old and old (13-month-old animals fed either a control diet or a diet supplemented with 1.0 mg selenium from seleniumenriched yeast (SP/kg diet were obtained and validated using microarray and real-time RTPCR techniques. Results: Aging led to significant transcriptional changes, where the expression of 1942 genes in old animals was changed by a fold change larger than 2.0, when compared to young animals. Age-regulated genes are associated with cardiovascular system development, immune and inflammatory response, and cellular oxidative stress response. Multiple genes linked with cardiomyocyte apoptosis, hypertrophy, and cardiac fibrosis, such as Myh7, Lcn2, Spp1, and Serpine1, were significantly up-regulated in old animals. SP supplementation also caused significant transcriptional changes in the heart, especially in old mice where many age-dependent transcriptional changes were totally or partially reversed by SP. Upstream regulator analysis further indicated that genes for Foxo1 and Foxo3, two transcriptional regulators involved in the regulation of cardiac muscle remodeling, were significantly activated by SP, suggesting that Foxo-mediated transcriptional activities play important roles in the anti-aging properties of SP. Functional Foods in Health and Disease 2014; 4(3:98- 119 Page 99 of 119 Conclusions: Results of this study indicate that SP supplementation attenuated age-related transcriptional changes in the heart of old POLG mice, which implies a potential clinical application of

  16. Selenium-enriched milk proteins and selenium yeast affect selenoprotein activity and expression differently in mouse colon.

    Science.gov (United States)

    Hu, Ying; McIntosh, Graeme H; Le Leu, Richard K; Young, Graeme P

    2010-07-01

    Certain forms of dietary Se may have an advantage in improving Se status and reducing cancer risk. The present study compared the effects of an Se-enriched milk protein product (dairy-Se) with an Se yeast (yeast-Se) on selenoprotein activity and expression in the mouse colon. Mice were fed four diets for 4 weeks: a control milk protein diet (Se at 0.068 parts per million (ppm)), dairy-Se diets with Se at 0.5 and 1 ppm, and a yeast-Se diet with Se at 1 ppm. Cytosolic glutathione peroxidase-1 (GPx-1) activity, mRNA of selenoprotein P (SeP), GPx-1, gastrointestinal glutathione peroxidase-2 (GPx-2) and thioredoxin reductase-1 (TrxR-1) were examined in the mouse colon. Dairy-Se diets did not significantly affect GPx-1 mRNA and GPx-1 activity but produced a dose-dependent increase in SeP and GPx-2 mRNA, with a significantly higher level achieved at 1 ppm Se (P supplement had any effect on TrxR-1. The present study indicates that selenoprotein levels in the mouse colon are regulated differently depending on the Se supplement. As we have previously shown that dairy-Se at 1 ppm was protective against colorectal cancer (CRC) in an azoxymethane-induced CRC mouse model, this up-regulation of colonic GPx-2 and SeP with Se supplementation may be crucial to its chemopreventive action.

  17. "Omics" of Selenium Biology: A Prospective Study of Plasma Proteome Network Before and After Selenized-Yeast Supplementation in Healthy Men.

    Science.gov (United States)

    Sinha, Indu; Karagoz, Kubra; Fogle, Rachel L; Hollenbeak, Christopher S; Zea, Arnold H; Arga, Kazim Y; Stanley, Anne E; Hawkes, Wayne C; Sinha, Raghu

    2016-04-01

    Low selenium levels have been linked to a higher incidence of cancer and other diseases, including Keshan, Chagas, and Kashin-Beck, and insulin resistance. Additionally, muscle and cardiovascular disorders, immune dysfunction, cancer, neurological disorders, and endocrine function have been associated with mutations in genes encoding for selenoproteins. Selenium biology is complex, and a systems biology approach to study global metabolomics, genomics, and/or proteomics may provide important clues to examining selenium-responsive markers in circulation. In the current investigation, we applied a global proteomics approach on plasma samples collected from a previously conducted, double-blinded placebo controlled clinical study, where men were supplemented with selenized-yeast (Se-Yeast; 300 μg/day, 3.8 μmol/day) or placebo-yeast for 48 weeks. Proteomic analysis was performed by iTRAQ on 8 plasma samples from each arm at baseline and 48 weeks. A total of 161 plasma proteins were identified in both arms. Twenty-two proteins were significantly altered following Se-Yeast supplementation and thirteen proteins were significantly changed after placebo-yeast supplementation in healthy men. The differentially expressed proteins were involved in complement and coagulation pathways, immune functions, lipid metabolism, and insulin resistance. Reconstruction and analysis of protein-protein interaction network around selected proteins revealed several hub proteins. One of the interactions suggested by our analysis, PHLD-APOA4, which is involved in insulin resistance, was subsequently validated by Western blot analysis. Our systems approach illustrates a viable platform for investigating responsive proteomic profile in 'before and after' condition following Se-Yeast supplementation. The nature of proteins identified suggests that selenium may play an important role in complement and coagulation pathways, and insulin resistance.

  18. Selenium homeostasis and induction of thioredoxin reductase during long term selenite supplementation in the rat

    DEFF Research Database (Denmark)

    Erkhembayar, Suvd; Mollbrink, Annelie; Eriksson, Malin

    2011-01-01

    drinking water containing 1μg/mL or 5μg/mL sodium selenite. Selenium levels were monitored in serum and liver tissue over the 10-week period, and the kinetics of induction of the redox-active cytosolic selenoenzyme thioredoxin reductase were followed. Selenite exposure via drinking water caused a dose......Selenium is a candidate treatment for liver tumour prevention in chronic liver disease. In this study, we have studied selenium uptake, distribution and accumulation in rats provided with water containing tumour-preventive doses of sodium selenite for 10weeks. Male Fischer 344 rats were given...... selenium levels was also seen, and the induction of TrxR1 mRNA was seen only during the first three days of treatment, when the levels of selenium in the liver were increasing. Sodium selenite at 1 and 5μg/mL did not affect body weight or relative liver mass. We concluded that long-term treatment...

  19. 21 CFR 573.920 - Selenium.

    Science.gov (United States)

    2010-04-01

    ... months.” (h) Selenium yeast is a dried, non-viable yeast (Saccharomyces cerevisiae) cultivated in a fed... additive; (4) selenium at such levels does not achieve its intended effect of promoting normal growth and... which minimizes the detrimental effects of selenium salts on the growth rate of the yeast and allows for...

  20. Acute exposure to selenium disrupts associative conditioning and long-term memory recall in honey bees (Apis mellifera).

    Science.gov (United States)

    Burden, Christina M; Elmore, Christopher; Hladun, Kristen R; Trumble, John T; Smith, Brian H

    2016-05-01

    A plethora of toxic compounds - including pesticides, heavy metals, and metalloids - have been detected in honey bees (Apis mellifera) and their colonies. One such compound is selenium, which bees are exposed to by consuming nectar and pollen from flowers grown in contaminated areas. Though selenium is lethal at high concentrations, sublethal exposure may also impair honey bees' ability to function normally. Examining the effect of selenium exposure on learning and memory provides a sensitive assay with which to identify sublethal effects on honey bee health and behavior. To determine whether sublethal selenium exposure causes learning and memory deficits, we used proboscis extension reflex conditioning coupled with recall tests 30min and 24h post-conditioning. We exposed forager honey bees to a single sublethal dose of selenium, and 3h later we used an olfactory conditioning assay to train the bees to discriminate between one odor associated with sucrose-reinforcement and a second unreinforced odor. Following conditioning we tested short- and long-term recall of the task. Acute exposure to as little as 1.8ng of an inorganic form of selenium (sodium selenate) before conditioning caused a reduction in behavioral performance during conditioning. And, exposure to 18ng of either an inorganic form (sodium selenate) or an organic form (methylseleno-l-cysteine) of selenium caused a reduction in the bees' performance during the long-term recall test. These concentrations of selenium are lower than those found in the nectar of plants grown in selenium-contaminated soil, indicating that even low-grade selenium toxicity produces significant learning and memory impairments. This may reduce foragers' ability to effectively gather resources for the colony or nurse bees' ability to care for and maintain a healthy colony. Copyright © 2016. Published by Elsevier Inc.

  1. Identification of anionic selenium species in Se-rich yeast by electrospray QTOF MS/MS and hybrid linear ion trap/orbitrap MSn.

    Science.gov (United States)

    Dernovics, Mihaly; Far, Johann; Lobinski, Ryszard

    2009-01-01

    An analytical approach allowing the identification of unknown selenium metabolites in selenium-rich yeast was described. Anion-exchange HPLC of the Se-metabolome fraction co-eluting with salts in size-exclusion chromatography allowed the separation of nine selenium species (excluding isomers and selenate) as monitored by inductively coupled plasma mass spectrometry (ICP MS). The individual fractions were analyzed by electrospray QTOF MS/MS and hybrid linear ion trap/Orbitrap MSn after sample introduction by reversed-phase nanoHPLC and by hydrophilic interaction LC (HILIC), respectively. Out of the nine detected species, eight were identified on the basis of accurate mass measurements and collision induced dissociation/fragmentation information. Seven Se-species (selenohomolanthionine, γ-Glu-selenocystathionine, 2,3-DHP-selenocystathionine, N-acetyl-selenocystathionine, 2,3-DHP-selenohomolanthionine, Se-methyl-selenoglutathione, and 2,3-DHP-Se-methylselenocysteine) were reported for the first time in Se-rich yeast, five of them have never been reported in any biological sample before.

  2. Randomised controlled trial of the effect of long-term selenium supplementation on plasma cholesterol in an elderly Danish population.

    Science.gov (United States)

    Cold, Frederik; Winther, Kristian H; Pastor-Barriuso, Roberto; Rayman, Margaret P; Guallar, Eliseo; Nybo, Mads; Griffin, Bruce A; Stranges, Saverio; Cold, Søren

    2015-12-14

    Although cross-sectional studies have shown a positive association between Se and cholesterol concentrations, a recent randomised controlled trial in 501 elderly UK individuals of relatively low-Se status found that Se supplementation for 6 months lowered total plasma cholesterol. The Danish PRECISE (PREvention of Cancer by Intervention with Selenium) pilot study (ClinicalTrials.gov ID: NCT01819649) was a 5-year randomised, double-blinded, placebo-controlled trial with four groups (allocation ratio 1:1:1:1). Men and women aged 60-74 years (n 491) were randomised to 100 (n 124), 200 (n 122) or 300 (n 119) μg Se-enriched yeast or matching placebo-yeast tablets (n 126) daily for 5 years. A total of 468 participants continued the study for 6 months and 361 participants, equally distributed across treatment groups, continued for 5 years. Plasma samples were analysed for total and HDL-cholesterol and for total Se concentrations at baseline, 6 months and 5 years. The effect of different doses of Se supplementation on plasma lipid and Se concentrations was estimated by using linear mixed models. Plasma Se concentration increased significantly and dose-dependently in the intervention groups after 6 months and 5 years. Total cholesterol decreased significantly both in the intervention groups and in the placebo group after 6 months and 5 years, with small and nonsignificant differences in changes in plasma concentration of total cholesterol, HDL-cholesterol, non-HDL-cholesterol and total:HDL-cholesterol ratio between intervention and placebo groups. The effect of long-term supplementation with Se on plasma cholesterol concentrations or its sub-fractions did not differ significantly from placebo in this elderly population.

  3. Yeast as a model system to study metabolic impact of selenium compounds

    Directory of Open Access Journals (Sweden)

    Enrique Herrero

    2015-04-01

    Full Text Available Inorganic Se forms such as selenate or selenite (the two more abundant forms in nature can be toxic in Saccharomyces cerevisiae cells, which constitute an adequate model to study such toxicity at the molecular level and the functions participating in protection against Se compounds. Those Se forms enter the yeast cell through other oxyanion transporters. Once inside the cell, inorganic Se forms may be converted into selenide through a reductive pathway that in physiological conditions involves reduced glutathione with its consequent oxidation into diglutathione and alteration of the cellular redox buffering capacity. Selenide can subsequently be converted by molecular oxygen into elemental Se, with production of superoxide anions and other reactive oxygen species. Overall, these events result in DNA damage and dose-dependent reversible or irreversible protein oxidation, although additional oxidation of other cellular macromolecules cannot be discarded. Stress-adaptation pathways are essential for efficient Se detoxification, while activation of DNA damage checkpoint and repair pathways protects against Se-mediated genotoxicity. We propose that yeast may be used to improve our knowledge on the impact of Se on metal homeostasis, the identification of Se-targets at the DNA and protein levels, and to gain more insights into the mechanism of Se-mediated apoptosis.

  4. Influence the oxidant action of selenium in radiosensitivity induction and cell death in yeast Saccharomyces cerevisiae; Influencia da acao oxidante do selenio na inducao da radiossensibilidade e morte celular na levedura Saccharomyces cerevisiae

    Energy Technology Data Exchange (ETDEWEB)

    Porto, Barbara Abranches de Araujo

    2012-07-01

    Ionizing radiations are from both natural sources such as from anthropogenic sources. Recently, radiotherapy has emerged as one of the most common therapies against cancer. Co-60 irradiators (cobalt-60 linear accelerators) are used to treat of malignant tumors routinely in hospitals around the world. Exposure to ionizing radiation can induce changes in cellular macromolecules and affect its functions, because they cause radiolysis of the water molecule generating reactive oxygen species, which can cause damage to virtually all organelles and cell components known as oxidative damage that can culminate in oxidative stress. Oxidative stress is a situation in which the balance between oxidants and antioxidants is broken resulting in excessive production of reactive species, it is not accompanied by the increase in antioxidant capacity, making it impossible to neutralize them. Selenium is a micronutrient considered as antioxidant, antiinflammatory, which could prevent cancer. Selenium in biological system exists as seleno proteins. Nowadays, 25 human seleno proteins have been identified, including glutathione peroxidase, an antioxidant enzyme. Yeasts have the ability to incorporate various metals such as iron, cadmium, zinc and selenium, as well as all biological organisms. The yeast Saccharomyces cerevisiae, unlike mammalian cells is devoid of seleno proteins, being considered as a practical model for studies on the toxicity of selenium, without any interference from the metabolism of seleno proteins. Moreover, yeast cells proliferate through the fermentation, the microbial equivalent of aerobic glycolysis in mammals and the process is also used by tumors. Several reports show that the pro-oxidante effects and induced toxic selenium compounds occur at lower doses and in malignant cells compared with benign cells. Therefore selenium giving a great therapeutic potential in cancer treatment .Our objective was to determine whether selenium is capable to sensitize yeasts

  5. Long-term organic selenium supplementation overcomes the trade-off between immune and antioxidant systems in pacu (Piaractus mesopotamicus).

    Science.gov (United States)

    Takahashi, Leonardo Susumu; Biller-Takahashi, Jaqueline Dalbello; Mansano, Cleber Fernando Menegasso; Urbinati, Elisabeth Criscuolo; Gimbo, Rodrigo Yukihiro; Saita, Marcos Vinícius

    2017-01-01

    Selenium (Se) is an essential nutrient for antioxidant defenses in fish because of its role in preventing immunosuppression caused by oxidative stress. In this study it was demonstrated the relation between the oxidative stress and immune status after a long Se supplementation period, as a result of the evaluation of immunological, hematological and antioxidant responses, as well as growth performance of pacu fed diets supplemented with different concentrations of organic selenium (0, 0.3, 0.6, 0.9, and 1.8 mg Se-yeast/kg, but the final analyzed selenium concentrations were 0.72, 0.94, 1.15, 1.57 and 2.51 mg/kg, respectively) for 65 days. Dietary Se supplementation at 1.15 mg Se-yeast/kg (analyzed value) restored the production of antioxidant enzymes (glutathione peroxidase (GPx) and glutathione S-transferase (GST)), and consequently allowed the increased of some immunological parameters (leukocyte respiratory burst activity and lysozyme activity), hematological parameters (red blood cell count (RBC), hematocrit (HTC), mean corpuscular volume (MCV), and white blood cell count (WBC)). Se supplementation in pacu diets at 1.15 mg Se-yeast/kg for 65 days improved immune response and antioxidant defenses, suggesting that oxidative stress impairs immune system response to prevent excessive reactive oxygen species in cells and indicating the occurrence of a physiological trade-off between immune and antioxidant systems. Higher Se levels, such as 1.57 mg Se-yeast/kg increased the leukocyte respiratory burst activity, the WBC and thrombocyte counts, the RBC and HTC, and the GST and GPx enzymes. However, 2.51 mg Se-yeast/kg decreased the lysozyme levels, the WBC and thrombocyte counts, the RBC, HTC and MCV, and the GST and GPx enzymes. Those findings are important to future studies because showed the negative effect of oxidative stress on immunity, and may help to prevent any inhibition of the expected immune response after immunomodulators administration and

  6. Selenium metabolomics in yeast using complementary reversed-phase/hydrophilic ion interaction (HILIC) liquid chromatography-electrospray hybrid quadrupole trap/Orbitrap mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Arnaudguilhem, C.; Bierla, K.; Ouerdane, L.; Preud' homme, H. [CNRS/UPPA, Laboratoire de Chimie Analytique Bio-inorganique et Environnement, UMR 5254, Helioparc, 2, Av. Pr. Angot, 64053 Pau (France); Yiannikouris, A. [Alltech Inc., 3031 Catnip Hill Pike, Nicholasville, KY (United States); Lobinski, R., E-mail: ryszard.lobinski@univ-pau.fr [CNRS/UPPA, Laboratoire de Chimie Analytique Bio-inorganique et Environnement, UMR 5254, Helioparc, 2, Av. Pr. Angot, 64053 Pau (France); Chair of Analytical Chemistry, Warsaw University of Technology, 00-664 Warszawa (Poland)

    2012-12-13

    Highlights: Black-Right-Pointing-Pointer The use of bimodal chromatographic separation enlarged amount of compounds identified. Black-Right-Pointing-Pointer The method allowed the largest scale ever (>60 compounds) speciation analysis of selenium metabolites in Se-rich yeast. Black-Right-Pointing-Pointer The estimated concentration of compounds was given. - Abstract: A high efficiency chromatographic separation on a porous graphitic carbon stationary phase was developed for a large-scale separation of selenium metabolites in Se-rich yeast prior to their identification by electrospray hybrid quadrupole trap/Orbitrap mass spectrometry (Orbitrap MS{sup n}). The reversed-phase (RP) separation mode offered distinctly higher separation efficiency than the hydrophilic ion interaction (HILIC) mode. The latter was nevertheless complementary and useful to validate the detection of several compounds. The method allowed the detection of 64 metabolites including 30 Se-Se or Se-S conjugates (3 triple S/Se/S ones) and 14 selenoethers. 21 previously unreported metabolites were detected on the basis of the selenium isotopic pattern usually matched with the sub-ppm mass accuracy. 9 of these metabolites were subsequently identified using the multi-stage high mass accuracy (<5 ppm) mass spectrometry. The identified metabolites (and their groups) were quantified on-line by ICP-MS fitted with a frequency-matching generator allowing a quasi-uniform response over the large (20-90%) acetonitrile mobile phase concentration range. The morphology of HPLC-ICP-MS chromatograms was remarkably similar to that of HPLC multi-ion extracted ESI-MS chromatograms. The detection limits obtained by ICP MS and ESI MS were 1 and 2 ppb, respectively.

  7. Reduction of splenic immunosuppressive cells and enhancement of anti-tumor immunity by synergy of fish oil and selenium yeast.

    Directory of Open Access Journals (Sweden)

    Hang Wang

    Full Text Available Growing evidence has shown that regulatory T cells (Tregs and myeloid-derived suppressor cells (MDSCs abnormally increase in cancer cachectic patients. Suppressions of Tregs and MDSCs may enhance anti-tumor immunity for cancer patients. Fish oil and selenium have been known to have many biological activities such as anti-inflammation and anti-oxidation. Whether fish oil and/or selenium have an additional effect on population of immunosuppressive cells in tumor-bearing hosts remained elusive and controversial. To gain insights into their roles on anti-tumor immunity, we studied the fish oil- and/or selenium-mediated tumor suppression and immunity on lung carcinoma, whereof cachexia develops. Advancement of cachexia in a murine lung cancer model manifested with such indicative symptoms as weight loss, chronic inflammation and disturbed immune functionality. The elevation of Tregs and MDSCs in spleens of tumor-bearing mice was positively correlated with tumor burdens. Consumption of either fish oil or selenium had little or no effect on the levels of Tregs and MDSCs. However, consumption of both fish oil and selenium together presented a synergistic effect--the population of Tregs and MDSCs decreased as opposed to increase of anti-tumor immunity when both fish oil and selenium were supplemented simultaneously, whereby losses of body weight and muscle/fat mass were alleviated significantly.

  8. Effects of selenium on short-term control of hyperthyroidism due to Graves' disease treated with methimazole: results of a randomized clinical trial.

    Science.gov (United States)

    Leo, M; Bartalena, L; Rotondo Dottore, G; Piantanida, E; Premoli, P; Ionni, I; Di Cera, M; Masiello, E; Sassi, L; Tanda, M L; Latrofa, F; Vitti, P; Marcocci, C; Marinò, M

    2017-03-01

    In spite of previous conflicting results, an adjuvant role of selenium in the treatment of Graves' disease (GD) hyperthyroidism has been proposed. To address this issue, a randomized clinical trial was carried out aimed at investigating whether selenium is beneficial on the short-term control of GD hyperthyroidism treated with methimazole (MMI). Thirty newly diagnosed hyperthyroid GD patients were randomly assigned to treatment with: (i) MMI or (ii) MMI plus selenium. Primary outcomes were: control of hyperthyroidism and clinical and biochemical manifestations of hyperthyroidism [heart rate, cholesterol, sex hormone-binding globulin (SHBG), hyperthyroidism symptoms] at 90 days. Baseline features of the two groups did not differ. Serum selenium at baseline was similar in the two groups and within the recommended range to define selenium sufficiency. Selenium increased with treatment in the MMI-selenium group and became significantly higher than in the MMI group. Serum malondialdehyde, a marker of oxidative stress, was similar in the two groups and decreased significantly with treatment, with no difference between groups. Administration of MMI was followed by a reduction of FT3 and FT4, with no difference between groups. Heart rate, SHBG and symptoms of hyperthyroidism decreased, whereas total cholesterol increased in both groups with no difference between groups. Our study, carried out in a selenium-sufficient cohort of GD patients, failed to show an adjuvant role of selenium in the short-term control of hyperthyroidism. However, selenium might be beneficial in patients from selenium-deficient areas, as well as in the long-term outcome of antithyroid treatment.

  9. Evaluation of selenium in dietary supplements using elemental speciation.

    Science.gov (United States)

    Kubachka, Kevin M; Hanley, Traci; Mantha, Madhavi; Wilson, Robert A; Falconer, Travis M; Kassa, Zena; Oliveira, Aline; Landero, Julio; Caruso, Joseph

    2017-03-01

    Selenium-enriched dietary supplements containing various selenium compounds are readily available to consumers. To ensure proper selenium intake and consumer confidence, these dietary supplements must be safe and have accurate label claims. Varying properties among selenium species requires information beyond total selenium concentration to fully evaluate health risk/benefits A LC-ICP-MS method was developed and multiple extraction methods were implemented for targeted analysis of common "seleno-amino acids" and related oxidation products, selenate, selenite, and other species relatable to the quality and/or accuracy of the labeled selenium ingredients. Ultimately, a heated water extraction was applied to recover selenium species from non-selenized yeast supplements in capsule, tablet, and liquid forms. For selenized yeast supplements, inorganic selenium was monitored as a means of assessing selenium yeast quality. A variety of commercially available selenium supplements were evaluated and discrepancies between labeled ingredients and detected species were noted. Published by Elsevier Ltd.

  10. Analyses of Selenotranscriptomes and Selenium Concentrations in Response to Dietary Selenium Deficiency and Age Reveal Common and Distinct Patterns by Tissue and Sex in Telomere-Dysfunctional Mice.

    Science.gov (United States)

    Cao, Lei; Zhang, Li; Zeng, Huawei; Wu, Ryan Ty; Wu, Tung-Lung; Cheng, Wen-Hsing

    2017-10-01

    Background: The hierarchies of tissue selenium distribution and selenotranscriptomes are thought to critically affect healthspan and longevity.Objective: We determined selenium status and selenotranscriptomes in response to long-term dietary selenium deficiency and age in tissues of male and female mice.Methods: Weanling telomerase RNA component knockout C57BL/6 mice were fed a selenium-deficient (0.03 mg Se/kg) Torula yeast-based AIN-93G diet or a diet supplemented with sodium selenate (0.15 mg Se/kg) until age 18 or 24 mo. Plasma, hearts, kidneys, livers, and testes were collected to assay for selenotranscriptomes, selected selenoproteins, and tissue selenium concentrations. Data were analyzed with the use of 2-factor ANOVA (diet × age) in both sexes.Results: Dietary selenium deficiency decreased (P ≤ 0.05) selenium concentrations (65-72%) and glutathione peroxidase (GPX) 3 (82-94%) and selenoprotein P (SELENOP) (17-41%) levels in the plasma of both sexes of mice and mRNA levels (9-68%) of 4, 4, and 12 selenoproteins in the heart, kidney, and liver of males, respectively, and 5, 16, and 14 selenoproteins, respectively, in females. Age increased selenium concentrations and SELENOP levels (27% and 30%, respectively; P ≤ 0.05) in the plasma of males only but decreased (12-46%; P selenium deficiency and age in ≥1 tissue or sex, or both. Dietary selenium deficiency upregulated (40-160%; P ≤ 0.05) iodothyronine deiodinase 2 (Dio2) and selenoprotein N (Selenon) in the kidneys of males. Age upregulated (11-44%; P selenium status and selenotranscriptomes because of dietary selenium deficiency and age. © 2017 American Society for Nutrition.

  11. Selenium Sulfide

    Science.gov (United States)

    Selenium sulfide, an anti-infective agent, relieves itching and flaking of the scalp and removes the dry, ... Selenium sulfide comes in a lotion and is usually applied as a shampoo. As a shampoo, selenium ...

  12. Analysis of the yeast short-term Crabtree effect and its origin.

    Science.gov (United States)

    Hagman, Arne; Säll, Torbjörn; Piškur, Jure

    2014-11-01

    The short-term Crabtree effect is defined as the immediate occurrence of aerobic alcoholic fermentation in response to provision of a pulse of excess sugar to sugar-limited yeast cultures. Here we have characterized ten yeast species with a clearly defined phylogenetic relationship. Yeast species were cultivated under glucose-limited conditions, and we studied their general carbon metabolism in response to a glucose pulse. We generated an extensive collection of data on glucose and oxygen consumption, and ethanol and carbon dioxide generation. We conclude that the Pichia, Debaryomyces, Eremothecium and Kluyveromyces marxianus yeasts do not exhibit any significant ethanol formation, while Kluyveromyces lactis behaves as an intermediate yeast, and Lachancea, Torulaspora, Vanderwaltozyma and Saccharomyces yeasts exhibit rapid ethanol accumulation. Based on the present data and our previous data relating to the presence of the long-term Crabtree effect in over 40 yeast species, we speculate that the origin of the short-term effect may coincide with the origin of the long-term Crabtree effect in the Saccharomycetales lineage, occurring ~ 150 million years ago. © 2014 The Authors. FEBS Journal published by John Wiley & Sons Ltd on behalf of FEBS.

  13. Selenium enrichment and anti-oxidant status in baker’s yeast, Saccharomyces cerevisiae at different sodium selenite concentrations Enriquecimiento con selenio y estado anti-oxidante de la levadura de harinas Saccharomyces Cerevisiae con diferentes concentraciones de selenito sódico

    OpenAIRE

    T. Kaur; M. P. Bansal

    2006-01-01

    The use of selenized yeast as enriched selenium supplements in human nutrition has become a topic of increasing interest over the last decade. The present study was designed with the aim to achieve a balance between selenium (Se) incorporation and optimal growth of yeast cells along with effect of Se enrichment on antioxidant defense status of yeast cells. Since oxidative stress has been known to play a role in the life span of all types of cells, so in the present studies anti-oxidant defens...

  14. Selenium modifies the effect of short-term chilling stress on cucumber plants.

    Science.gov (United States)

    Hawrylak-Nowak, Barbara; Matraszek, Renata; Szymańska, Maria

    2010-12-01

    The objective of this study was to investigate the effect of selenium (Se) supply (0, control; 2.5, 5, 10, or 20 μM) on cucumber (Cucumis sativus L.) cv. Polan F1 plants grown under short-term low temperature stress. About 14-16 day-old seedlings, grown at an optimal temperature (25/20°C; day/night), were exposed to short-term chilling stress with a day/night temperature of 10°C/5°C for 24 h, for a further 24 h at 20°C/15°C, and then transferred to 25/20°C (re-warming) for 7 days. Se did not affect the fresh weight (FW) of plants at a concentration of 2.5-10 μM, but in the presence of 20 μM Se, the biomass of shoots significantly decreased. The contents of chlorophylls and carotenoids witnessed no significant change after Se supplementation. Compared with the control, the Se-treated plants showed an increase of proline content in leaves, once after chilling and again after 7 days of re-warming. However, proline levels were much higher immediately after chilling than after re-warming. The malondialdehyde (MDA) content in the root of plants treated with 2.5-10 μM Se decreased directly after stress. This was in comparison with the plants grown without Se, whereas it increased in roots and leaves of plants exposed to 20 μM Se. Seven days later, the MDA level in the root of plants grown in the presence of Se was still lower than those of plants not treated with Se and generally witnessed no significant change in leaves. Although Se at concentrations of 2.5-10 μM modified the physiological response of cucumber to short-term chilling stress, causing an increase in proline content in leaves and diminishing lipid peroxidation in roots, the resistance of plants to low temperature was not clearly enhanced, as concluded on the basis of FW and photosynthetic pigments accumulation.

  15. Selenium and cancer: biomarkers of selenium status and molecular action of selenium supplements.

    OpenAIRE

    Gromadzinska, Jolanta; Reszka, Edyta; Bruzelius, Katharina; Wasowicz, Wojciech; Akesson, Bjorn

    2008-01-01

    BACKGROUND: The relationship between selenium and cancer involves many different aspects. These include the forms of selenium present in the diet and in the body, their functions and mechanisms of action, and methods employed in assessing an individual's selenium nutritional status-both in general, and in epidemiological studies of the risk of cancer in relation to diet, as well as in connection with long-term trials for investigating the disease-preventive potential of selenium supplementati...

  16. Selenium for preventing cancer

    Directory of Open Access Journals (Sweden)

    Gabriele Dennert

    Full Text Available BACKGROUND: Selenium is a trace element essential to humans. Higher selenium exposure and selenium supplements have been suggested to protect against several types of cancers. OBJECTIVE: Two research questions were addressed in this review: What is the evidence for: 1. an aetiological relationship between selenium exposure and cancer risk in women and men?; 2. the efficacy of selenium supplementation for cancer prevention in women and men? SEARCH STRATEGY: We searched electronic databases and bibliographies of reviews and included publications. SELECTION CRITERIA: We included prospective observational studies to answer research question (a and randomised controlled trials (RCTs to answer research question (b. DATA COLLECTION AND ANALYSIS: We conducted random effects meta-analyses of epidemiological data when five or more studies were retrieved for a specific outcome. We made a narrative summary of data from RCTs. MAIN RESULTS: We included 49 prospective observational studies and six RCTs. In epidemiologic data, we found a reduced cancer incidence (summary odds ratio, OR, 0.69; 95% confidence interval, CI, 0.53 to 0.91 and mortality (OR 0.55, 95% CI 0.36 to 0.83 with higher selenium exposure. Cancer risk was more pronouncedly reduced in men (incidence: OR 0.66, 95% CI 0.42 to 1.05 than in women (incidence: OR 0.90, 95% CI 0.45 to 1.77. These findings have potential limitations due to study design, quality and heterogeneity of the data, which complicated the interpretation of the summary statistics. The RCTs found no protective efficacy of selenium yeast supplementation against non-melanoma skin cancer or L-selenomethionine supplementation against prostate cancer. Study results for the prevention of liver cancer with selenium supplements were inconsistent and studies had an unclear risk of bias. The results of the Nutritional Prevention of Cancer Trial (NPCT and SELECT raised concerns about possible harmful effects of selenium supplements. AUTHORS

  17. The Protective Effect of Cell Wall and Cytoplasmic Fraction of Selenium Enriched Yeast on 1, 2-Dimethylhydrazine-induced Damage in Liver

    Directory of Open Access Journals (Sweden)

    Mitra Dadrass

    2014-02-01

    Full Text Available Background: 1, 2-Dimethylhydrazine (DMH enhances lipid peroxidation rate by tumor mitochondria than normal tissue counterpart and causes many disorders in antioxidant system in liver. It also increases the level of enzymes that metabolize toxin in liver and colon. The aim of this study was to evaluate the alteration of liver and its enzymes after DMH injection and evaluate protective effect of cell wall and cytoplasmic fractions of Saccharomyces cereviseae enriched with selenium (Se on these tissues. Materials and Methods: Forty eight female rats were prepared and acclimatized to the laboratory conditions for two weeks, and all animals received 1, 2- dimethyl hydrazine chloride (40 mg/kg body weight twice a week for 4 weeks except healthy control. At first colon carcinoma (aberrant crypt foci confirmed by light microscope. Then the changes resulting from injection of DMH on liver of animals in initial and advanced stages of colon cancer were examined. In addition, the protective effect of cell wall and cytoplasmic fractions of Selenium-enriched S. cerevisiae were investigated in two phases. First phase in initial stage and second phase in advanced stage of colon cancer were performed respectively. Forty weeks following the first DMH injection, all survived animals were sacrificed. Then, colon and liver removed and exsanguinated by heart puncture. For measuring the levels of enzymes (AST, ALT, and ALP, a commercial kit (Parsazmoon, Iran and an autoanalyzer (BT 3000 Pluse, Italy were used. Results: The results showed that subcutaneous injection of DMH increased the ALT, AST, and ALP levels up to 78.5, 161.38, and 275.88 U/L compared to the control, respectively. Moreover, statistical analysis in both phases of experiment revealed that the enzyme levels were decreased in the treated groups in comparison with the DMH-injected group, while the levels of these enzymes were lower in the control group. Conclusion: It should be concluded that

  18. The effects of short-term selenium stress on Polish and Finnish wheat seedlings-EPR, enzymatic and fluorescence studies.

    Science.gov (United States)

    Łabanowska, Maria; Filek, Maria; Kościelniak, Janusz; Kurdziel, Magdalena; Kuliś, Ewa; Hartikainen, Helina

    2012-02-15

    Biochemical analyses of antioxidant content were compared with measurements of fluorescence and electron paramagnetic resonance (EPR) to examine the alteration of radicals in wheat seedlings exposed to 2 days of selenium stress. Two genotypes of Polish and one of Finnish wheat, differing in their tolerance to long-term stress treatment, were cultured under hydroponic conditions to achieve the phase of 3-leave seedlings. Afterwards, selenium (sodium selenate, 100 μM concentration) was added to the media. After Se-treatment, all varieties showed an increase in carbohydrates (soluble and starch), ascorbate and glutathione content in comparison to non-stressed plants. These changes were more visible in Finnish wheat. On the basis of lipid peroxidation measurements, Finnish wheat was recognized as the genotype more sensitive to short-term Se-stress than the Polish varieties. The antioxidant enzyme activities (superoxide dismutase, ascorbate peroxidase and glutathione reductase) increased in Polish genotypes, whereas they decreased in Finnish wheat plants cultured on Se media. The action of reactive oxygen species in short-term action of Se stress was confirmed by the reduction of PSII and PSI system activities (measured by fluorescence parameters and EPR, respectively). EPR studies showed changes in redox status (especially connected with Mn(II)/Mn(III), and semiquinone/quinone ratios) in wheat cell after Se treatment. The involvement of the carbohydrate molecules as electron traps in production of long-lived radicals is postulated. Copyright © 2011 Elsevier GmbH. All rights reserved.

  19. [Two cases of long-term home parenteral nutrition in which increased doses of intravenous selenium were administered and the serum and hair selenium concentration was measured].

    Science.gov (United States)

    Washizawa, Naohiro; Kozono, Koki; Naganuma, Hirokazu; Kimura, Yuki; Sato, Yukihiko; Sakai, Masahiro; Chino, Kenichi; Shimoda, Masato; Suzuki, Takashi; Oshima, Yoko; Kaneko, Hiromasa

    2013-12-01

    Care should be taken regarding the intravenous administration of selenium (Se), an essential element, which is known to be associated with toxemia. The concentration of Se in the serum and hair of 2 patients (patient A and B) with short bowel syndrome, undergoing long-term home parenteral nutrition (HPN), was measured. As nutritional management, commercial total parenteral nutrition infusion was used without restricting oral intake. The patients received sodium selenite (Na2O3Se x 5H2O), a hospital preparation, at the Toho University Omori Medical Center. The dosage was gradually increased from 40 microg/ week to 120 micog/week over 17 months, and the Se concentration in serum and hair was measured bimonthly using inductively coupled plasma mass spectrometry (ICP-MS). The serum concentration of Se increased from 2.0 to 5.3 microg/dL and from 9.0 to 9.7 microg/dL in the case of patient A and B, respectively; however, it did not reach the average value that was observed in healthy volunteers (11.8 microg/dL). In contrast, the concentration of Se in hair gradually approached the reference value (reference range, 405-784 ppb at color correction criteria range 217-520 ppb) in the case of patient A (change from 189 to 278 ppb) and B (change from 291 to 200 ppb). Therefore, we were able to safely manage these cases without any deficiency and poisoning symptoms, by gradually increasing the administration doses.

  20. Effect of short-term zinc supplementation on zinc and selenium tissue distribution and serum antioxidant enzymes.

    Science.gov (United States)

    Skalny, Andrey A; Tinkov, Alexey A; Medvedeva, Yulia S; Alchinova, Irina B; Karganov, Mikhail Y; Skalny, Anatoly V; Nikonorov, Alexandr A

    2015-01-01

    A significant association between Zn and Se homeostasis exists. At the same time, data on the influence of zinc supplementation on selenium distribution in organs and tissues seem to be absent. Therefore, the primary objective of the current study is to investigate the influence of zinc asparaginate supplementation on zinc and selenium distribution and serum superoxide dismutase (SOD) and glutathione peroxidase (GPx) activity in Wistar rats. 36 rats were used in the experiment. The duration of the experiment was 7 and 14 days in the first and second series, respectively. The rats in Group I were used as the control ones. Animals in Groups II and III daily obtained zinc asparaginate (ZnA) in the doses of 5 and 15 mg/kg weight, respectively. Zinc and selenium content in liver, kidneys, heart, muscle, serum and hair was assessed using inductively coupled plasma mass spectrometry. Serum SOD and GPx activity was analysed spectrophotometrically using Randox kits. Intragastric administration of zinc asparaginate significantly increased liver, kidney, and serum zinc content without affecting skeletal and cardiac muscle levels. Zinc supplementation also stimulated selenium retention in the rats' organs. Moreover, a significant positive correlation between zinc and selenium content was observed. Finally, zinc asparaginate treatment has been shown to modulate serum GPx but not SOD activity. The obtained data indicate that zinc-induced increase in GPx activity may be mediated through modulation of selenium status. However, future studies are required to estimate the exact mechanisms of zinc and selenium interplay.

  1. Speciation of selenoamino acids, selenonium ions and inorganic selenium by ion exchange HPLC with mass spectrometric detection and its application to yeast and algae

    DEFF Research Database (Denmark)

    Larsen, Erik Huusfeldt; Hansen, M.; Fan, T.

    2001-01-01

    Cation and anion exchange HPLC were used to separate a mixture of 12 selenium species comprising selenoamino acids, selenonium ions and inorganic selenium. The cationic species were separated from each other and from the co-injected anions using a cation exchange column with gradient elution...... by aqueous pyridinium formate at pH similar to 3 as the mobile phase. The anionic species were separated using an anion exchange column with isocratic elution by an aqueous salicylate-TRIS mobile phase at pH 8.5. The separated selenium species were detected as Se-80 by ICP-dynamic reaction cell (DRC...... acid extract of Chlorella algae contained dimethylselenonium propionate (DMSeP), which was verified by HPLC-ES-MS. Se-allylselenocysteine and selenoethionine was detected at the low ng g(-1) concentration level based on co-chromatography with the standard substances spiked to the algal extract....

  2. Advanced prostate cancer risk in relation to toenail selenium levels

    NARCIS (Netherlands)

    Geybels, M.S.; Verhage, B.A.J.; Schooten, F.J. van; Goldbohm, A.; Brandt, P.A. van den

    2013-01-01

    BACKGROUND: Selenium may prevent advanced prostate cancer (PCa), but most studies on this topic were conducted in populations with moderate to high selenium status. We investigated the association of toenail selenium, reflecting long-term selenium exposure, and advanced PCa risk in a population from

  3. Selenium essentials

    CERN Document Server

    Sams, Prashanth

    2015-01-01

    If you are a developer who wants to migrate from Selenium RC or any other automation tool to Selenium WebDriver, then this book is for you. Knowledge of automation tools is necessary to follow the examples in this book.

  4. Selenium speciation and isotope composition in 77Se-enriched yeast using gradient elution HPLC separation and ICP-dynamic reaction cell-MS

    DEFF Research Database (Denmark)

    Larsen, Erik Huusfeldt; Sloth, Jens Jørgen; Hansen, M.

    2003-01-01

    using the enriched Se-77-selenite as substrate, were released by enzymatic hydrolysis using (I), a beta-glucosidase followed by a protease mixture, and (II), a commercial protease preparation. For selenium speciation the chromatographic selectivity of the cation exchange HPLC system was adjusted...

  5. ‘‘Omics’’ of Selenium Biology: A Prospective Study of Plasma Proteome Network Before and After Selenized-Yeast Supplementation in Healthy Men

    Science.gov (United States)

    Low selenium levels have been linked to a higher incidence of cancer and other diseases, including Keshan,Chagas, and Kashin–Beck, and insulin resistance. Additionally, muscle and cardiovascular disorders, immune dysfunction, cancer, neurological disorders, and endocrine function have been associate...

  6. Speciation of selenium dietary supplements; formation of S-(methylseleno)cysteine and other selenium compounds

    Energy Technology Data Exchange (ETDEWEB)

    Amoako, Prince O. [Department of Chemistry, University of Massachusetts Amherst, 710 N. Pleasant St., Amherst, MA 01003-9336 (United States); Uden, Peter C., E-mail: pcuden@chem.umass.edu [Department of Chemistry, University of Massachusetts Amherst, 710 N. Pleasant St., Amherst, MA 01003-9336 (United States); Tyson, Julian F. [Department of Chemistry, University of Massachusetts Amherst, 710 N. Pleasant St., Amherst, MA 01003-9336 (United States)

    2009-10-12

    Speciation of selenium is of interest because it is both essential and toxic to humans, depending on the species and the amount ingested. Following indications that selenium supplementation could reduce the incidence of some cancers, selenium-enriched yeast and other materials have been commercialized as supplements. Most dramatically however, the SELECT trial that utilized L-selenomethionine as the active supplement was terminated in 2008 and there is much debate regarding both the planning and the results of efficacy studies. Further, since dietary supplements are not regulated as pharmaceuticals, there are concerns about the quality, storage conditions, stability and selenium content in selenium supplements. Enzymatic hydrolysis enabled selenium speciation profiles to be obtained by high performance liquid chromatography with inductively coupled plasma mass spectrometry (HPLC-ICP-MS) and following derivatization gas chromatography with atomic emission detection (GC-AED). Coated fiber solid phase microextraction (SPME) was used to extract volatile selenium species for determination by GC-AED and GC-MS. Similar speciation patterns were observed between yeast-based supplements subject to extended storage and those heated briefly at elevated temperatures. All the yeast-based supplements and one yeast-free supplement formed S-(methylseleno)cysteine on heating. Evidence was obtained in support of the hypotheses that S-(methylseleno)cysteine is formed from a reaction between dimethyldiselenide and cysteine or cystine.

  7. Randomised controlled trial of the effect of long-term selenium supplementation on plasma cholesterol in an elderly Danish population

    DEFF Research Database (Denmark)

    Cold, Frederik; Winther, Kristian H; Pastor-Barriuso, Roberto

    2015-01-01

    PRECISE (PREvention of Cancer by Intervention with Selenium) pilot study (ClinicalTrials.gov ID: NCT01819649) was a 5-year randomised, double-blinded, placebo-controlled trial with four groups (allocation ratio 1:1:1:1). Men and women aged 60-74 years (n 491) were randomised to 100 (n 124), 200 (n 122...

  8. A short-term intervention trial with selenate, selenium-enriched yeast and selenium-enriched milk: effects on oxidative defence regulation

    DEFF Research Database (Denmark)

    Ravn-Haren, Gitte; Bugel, Susanne; Krath, Britta

    2008-01-01

    Increased Se intakes have been associated with decreased risk of cancer and CVD. Several mechanisms have been proposed, including antioxidant effects through selenoproteins, induction of carcinogen metabolism and effects on the blood lipid profile. In a 4 x 1 week randomised, double-blind cross...... activities in thrombocytes. Leucocyte expression of genes encoding selenoproteins (GPX1, TrR1 and SelP), and of electrophile response element-regulated genes (GCLC, Fra1 and NQO1) were likewise unaffected at all time points following intervention. We conclude that thrombocyte GPX is specifically increased...

  9. A new methodology involving stable isotope tracer to compare short- and long- term selenium mobility in soils

    Science.gov (United States)

    Tolu, Julie; Thiry, Yves; Potin-gautier, Martine; Le hécho, Isabelle; Bueno, Maïté

    2013-04-01

    Selenium is an element of environmental concern given its dual beneficial and toxic character to animal and human health. Its radioactive isotope 79Se, a fission product of 235U, is considered critical in safety assessment of nuclear waste repositories in case of leakage and hypothetical soil contamination. Therefore, Se species transformations and interactions with soil components have to be clearly understood to predict its dispersion in the biosphere (e.g., accumulation in soils, migration to waters, transfer to living organisms). While natural Se interactions with soils run over centuries to millennia time scales, transformations and partitioning are generally studied with short-term experiments (often inferior to 1 month) after Se addition. The influence of slower, long-term processes involved in Se speciation and mobility in soils is thus not properly accounted for. We tested if using ambient Se would be relevant for long-term risk assessment while added Se would be more representative of short-term contamination impact. For that purpose, we developed a new methodology to trace the differential reactivity of ambient and spiked Se at trace level (µg kg-1) in soils. It combined the use of a stable isotopically enriched tracer with our previous published analytical method based on specific extractions and HPLC-ICP-MS to determine trace Se species partition in different soil phases. Given that soil extracts contains very high concentrations of various elements interfering Se (e.g., Fe, Cl, Br), the ICP-MS parameters and mathematical corrections were optimized to cope with such interferences. Following optimization, three correct and accurate (<2%) isotope ratios were obtained with 77Se, 78Se, 80Se and 82Se. The optimized method was then applied to an arable and a forest soil submitted to an aging process (drying/wetting cycles) during three months, to which 77Se(IV) was previously added. The results showed that ambient Se was at steady state in terms of water

  10. Selenium biofortification

    Science.gov (United States)

    Plant foods are the major dietary sources of selenium (Se) in most countries around the world, followed by meats and seafood. For this reason, it is vital to increase Se uptake by plants and to produce crops with higher Se concentrations and bioavailability in their edible tissues. One of the most p...

  11. Can yeast glycolysis be understood in terms of in vitro kinetics of the constituent enxymes? Testing biochemistry.

    NARCIS (Netherlands)

    Teusink, B.; Passarge, J.R.; Reijenga, C.A.; Esgalhado, M.E.L.M.; van der Weijden, C.C.; Schepper, M.; Walsh, M.C.; Bakker, B.M.; van Dam, K.; Westerhoff, H.V.; Snoep, J.L.

    2000-01-01

    This paper examines whether the in vivo behavior of yeast glycolysis can be understood in terms of the in vitro kinetic properties of the constituent enzymes. In nongrowing, anaerobic, compressed Saccharomyces cerevisiae the values of the kinetic parameters of most glycolytic enzymes were

  12. Selenium: environmental significance, pollution, and biological treatment technologies.

    Science.gov (United States)

    Tan, Lea Chua; Nancharaiah, Yarlagadda V; van Hullebusch, Eric D; Lens, Piet N L

    2016-01-01

    Selenium is an essential trace element needed for all living organisms. Despite its essentiality, selenium is a potential toxic element to natural ecosystems due to its bioaccumulation potential. Though selenium is found naturally in the earth's crust, especially in carbonate rocks and volcanic and sedimentary soils, about 40% of the selenium emissions to atmospheric and aquatic environments are caused by various industrial activities such as mining-related operations. In recent years, advances in water quality and pollution monitoring have shown that selenium is a contaminant of potential environmental concern. This has practical implications on industry to achieve the stringent selenium regulatory discharge limit of 5μgSeL(-1) for selenium containing wastewaters set by the United States Environmental Protection Agency. Over the last few decades, various technologies have been developed for the treatment of selenium-containing wastewaters. Biological selenium reduction has emerged as the leading technology for removing selenium from wastewaters since it offers a cheaper alternative compared to physico-chemical treatments and is suitable for treating dilute and variable selenium-laden wastewaters. Moreover, biological treatment has the advantage of forming elemental selenium nanospheres which exhibit unique optical and spectral properties for various industrial applications, i.e. medical, electrical, and manufacturing processes. However, despite the advances in biotechnology employing selenium reduction, there are still several challenges, particularly in achieving stringent discharge limits, the long-term stability of biogenic selenium and predicting the fate of bioreduced selenium in the environment. This review highlights the significance of selenium in the environment, health, and industry and biotechnological advances made in the treatment of selenium contaminated wastewaters. The challenges and future perspectives are overviewed considering recent

  13. Updates on clinical studies of selenium supplementation in radiotherapy.

    Science.gov (United States)

    Puspitasari, Irma M; Abdulah, Rizky; Yamazaki, Chiho; Kameo, Satomi; Nakano, Takashi; Koyama, Hiroshi

    2014-05-29

    To establish guidelines for the selenium supplementation in radiotherapy we assessed the benefits and risks of selenium supplementation in radiotherapy. Clinical studies on the use of selenium in radiotherapy were searched in the PubMed electronic database in January 2013. Sixteen clinical studies were identified among the 167 articles selected in the initial search. Ten articles were observational studies, and the other 6 articles reported studies on the effects of selenium supplementation in patients with cancer who underwent radiotherapy. The studies were conducted worldwide including European, American and Asian countries between 1987 and 2012. Plasma, serum or whole blood selenium levels were common parameters used to assess the effects of radiotherapy and the selenium supplementation status. Selenium supplementation improved the general conditions of the patients, improved their quality of life and reduced the side effects of radiotherapy. At the dose of selenium used in these studies (200-500 μg/day), selenium supplementation did not reduce the effectiveness of radiotherapy, and no toxicities were reported. Selenium supplementation may offer specific benefits for several types of cancer patients who undergo radiotherapy. Because high-dose selenium and long-term supplementation may be unsafe due to selenium toxicity, more evidence-based information and additional research are needed to ensure the therapeutic benefits of selenium supplementation.

  14. Updates on clinical studies of selenium supplementation in radiotherapy

    Science.gov (United States)

    2014-01-01

    To establish guidelines for the selenium supplementation in radiotherapy we assessed the benefits and risks of selenium supplementation in radiotherapy. Clinical studies on the use of selenium in radiotherapy were searched in the PubMed electronic database in January 2013. Sixteen clinical studies were identified among the 167 articles selected in the initial search. Ten articles were observational studies, and the other 6 articles reported studies on the effects of selenium supplementation in patients with cancer who underwent radiotherapy. The studies were conducted worldwide including European, American and Asian countries between 1987 and 2012. Plasma, serum or whole blood selenium levels were common parameters used to assess the effects of radiotherapy and the selenium supplementation status. Selenium supplementation improved the general conditions of the patients, improved their quality of life and reduced the side effects of radiotherapy. At the dose of selenium used in these studies (200–500 μg/day), selenium supplementation did not reduce the effectiveness of radiotherapy, and no toxicities were reported. Selenium supplementation may offer specific benefits for several types of cancer patients who undergo radiotherapy. Because high-dose selenium and long-term supplementation may be unsafe due to selenium toxicity, more evidence-based information and additional research are needed to ensure the therapeutic benefits of selenium supplementation. PMID:24885670

  15. Bio-transformation of selenium in Se-enriched bacterial strains of Lactobacillus casei.

    Science.gov (United States)

    Kurek, Eliza; Ruszczyńska, Anna; Wojciechowski, Marcin; Łuciuk, Anna; Michalska-Kacymirow, Magdalena; Motyl, Ilona; Bulska, Ewa

    Selenium is an element of very great importance for the proper functioning of the human body, mainly due to its antioxidant properties. Selenium exhibits a preventive effect in the case of cardiovascular disease, the immune system, male infertility and inhibits the toxic action of other agents. Selenium is important for Hashimoto's disease. Intake of selenium in the diet slows the aging process. The biological and toxicological effects of selenium strongly depend on its chemical form. Some organisms for example: plant, yeast, are capable of metabolizing low bioavailable selenium compounds (inorganic selenium) into its high bioavailable forms (organic selenium). The aim of this study was to investigate the bio-transformation of selenium by Lactobacillus bacteria towards the characterisation of selenium metabolites. The speciation of selenium was evaluated by high performance liquid chromatography with inductively coupled plasma mass spectrometry detector. The extraction of selenium species from lyophilized bacteria was executed with water, the mixture of lipase and protease, as well as lisozyme and sodium dodecyl sulphate. All investigated bacteria strains cultivated in the presence of Na2SeO3 effectively uptake selenium. Surprisingly, none of the applied extraction media exhibited a strong power to release the majority of the uptaken selenium compounds. Thus a maximum of 10% of the selenium was extracted from bacteria exposed to the enzymes. However, it was found that Lactobacillus bacteria are able to metabolize inorganic ions of selenium (IV) into Se-methionine, Se-methyloselenocysteine and other unidentified forms. The study confirmed the ability of probiotic bacteria to biotransform inorganic selenium into its organic derivatives. Therefore, Se-enriched bacteria can be considered as an addition to the functional food. selenium speciation, extraction procedure, Lactobacillus casei bacteria, Lactic acid bacteria (LAB), HPLC ICP-MS, functional food.

  16. Long-term selenium supplementation in HaCaT cells: importance of chemical form for antagonist (protective versus toxic) activities.

    Science.gov (United States)

    Hazane-Puch, Florence; Champelovier, Pierre; Arnaud, Josiane; Garrel, Catherine; Ballester, Bruno; Faure, Patrice; Laporte, François

    2013-08-01

    The beneficial effect of selenium (Se) on cancer is known to depend on the chemical form, the dose and the duration of the supplementation. The aim of this work was to explore long term antagonist (antioxidant versus toxic) effects of an inorganic (sodium selenite, Na2SeO3) and an organic (seleno-L-methionine, SeMet) forms in human immortalized keratinocytes HaCaT cells. HaCaT cells were supplemented with Na2SeO3 or SeMet at micromolar concentrations for 144 h, followed or not by UVA radiation. Se absorption, effects of UVA radiation, cell morphology, antioxidant profile, cell cycle processing, DNA fragmentation, cell death triggered and caspase-3 activity were determined. At non-toxic doses (10 μM SeMet and 1 μM Na2SeO3), SeMet was better absorbed than Na2SeO3. The protection of HaCaT from UVA-induced cell death was observed only with SeMet despite both forms increased glutathione peroxidase-1 (GPX1) activities and selenoprotein-1 (SEPW1) transcript expression. After UVA irradiation, malondialdehyde (MDA) and SH groups were not modulated whatever Se chemical form. At toxic doses (100 μM SeMet and 5 μM Na2SeO3), Na2SeO3 and SeMet inhibited cell proliferation associated with S-G2 blockage and DNA fragmentation leading to apoptosis caspase-3 dependant. SeMet only led to hydrogen peroxide production and to a decrease in mitochondrial transmembrane potential. Our study of the effects of selenium on HaCaT cells reaffirm the necessity to take into account the chemical form in experimental and intervention studies.

  17. Selenium levels of Estonians.

    Science.gov (United States)

    Rauhamaa, P; Kantola, M; Viitak, A; Kaasik, T; Mussalo-Rauhamaa, H

    2008-09-01

    The objective of this study is to sum up the dietary selenium intake of the Estonian people according to the serum selenium concentrations. This research compiles the information published in the literature about the levels of selenium in the serum of the Estonian people. We compare these results with the findings obtained from the analyses of serum samples gathered by us in the 1990s in Estonia. The selenium concentration in sera of 404 Estonians ranged from 26 to 116 microg/l; the mean was 75 microg/l. The selenium contents of Estonians were at a similar level as reported for Finns before the selenium supplementation of fertilizers carried out in Finland in 1984. In view of the selenium concentration in the sera, we suggest that the dietary selenium intake among the Estonian people might be scarce, and Estonian authorities should consider in their nutrition policies the possible low intake of selenium of Estonians.

  18. Three-dimensional hierarchical porous tubular carbon as a host matrix for long-term lithium-selenium batteries

    Science.gov (United States)

    Jia, Min; Lu, Shiyu; Chen, Yuming; Liu, Ting; Han, Jin; Shen, Bolei; Wu, Xiaoshuai; Bao, Shu-Juan; Jiang, Jian; Xu, Maowen

    2017-11-01

    Lithium-selenium (Li-Se) batteries are of great interest as a representative family of electrochemical energy storage systems because of their high theoretical volumetric capacity and considerable electronic conductivity. However, the main drawback of Se electrodes is the rapid capacity fading caused by the dissolution of polyselenides upon cycling. Here, we report a simple, economical, and effective method for the synthesis of three-dimensional (3D) hierarchical porous carbon with a hollow tubular structure as a host matrix for loading Se and trapping polyselenides. The as-obtained porous tubular carbon shows a superior specific surface area of 1786 m2 g-1, a high pore volume of 0.79 cm3 g-1, and many nanostructured pores. Benefiting from the unique structural characteristics, the resulting hierarchical porous carbon/Se composite exhibits a high capacity of 515 mAh g-1 at 0.2 C. More importantly, a remarkable cycling stability over 900 cycles at 2 C with a capacity fading rate of merely 0.02% per cycle can be achieved. The 3D hollow porous tubular carbon can be also used for other high-performance electrodes of electrochemical energy storage.

  19. Inhibition of yeast growth during long term exposure to laser light around 1064 nm

    DEFF Research Database (Denmark)

    Aabo, Thomas; Perch-Nielsen, Ivan R.; Dam, Jeppe Seidelin

    2009-01-01

    We have studied the effect of a 1070 nm continuous wave Ytterbium fiber laser on exponentially growing Saccharomyces cerevisiae yeast cells over a span of 4 hours. The cells were immobilized onto Concanavalin A covered microscope slides and the growth was measured using the area increase of the c......We have studied the effect of a 1070 nm continuous wave Ytterbium fiber laser on exponentially growing Saccharomyces cerevisiae yeast cells over a span of 4 hours. The cells were immobilized onto Concanavalin A covered microscope slides and the growth was measured using the area increase...

  20. Biomarkers of selenium status in dogs

    OpenAIRE

    Van Zelst, Marielle; Hesta, Myriam; Gray, Kerry; Staunton, Ruth; Du Laing, Gijs; Janssens, Geert

    2016-01-01

    Background: Inadequate dietary selenium (Se) intake in humans and animals can lead to long term health problems, such as cancer. In view of the owner's desire for healthy longevity of companion animals, the impact of dietary Se provision on long term health effects warrants investigation. Little is currently known regards biomarkers, and rate of change of such biomarkers in relation to dietary selenium intake in dogs. In this study, selected biomarkers were assessed for their suitability to d...

  1. Selenium: Poison and Preventive.

    Science.gov (United States)

    Marmion Howe, Sister

    1978-01-01

    Selenium is an essential nutrient to the human body, but it can reach toxic levels causing a disease called selenosis. This article discusses selenium, its geographical distribution, toxicity, nutritional role, and carcinogenicity. (MA)

  2. Selenium: Element of Contrasts

    Science.gov (United States)

    Goldsmith, Robert H.; And Others

    1978-01-01

    Reports on recent findings concerning the impact of selenium on human and animal health. In its various oxidation states, different concentrations of selenium may be helpful or detrimental to human health. (CP)

  3. Selenium in diet

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/002414.htm Selenium in diet To use the sharing features on this page, please enable JavaScript. Selenium is an essential trace mineral. This means your ...

  4. Aquatic Life Criterion - Selenium

    Science.gov (United States)

    Documents pertaining to the 2016 Acute and Chronic Ambient Aquatic Life Water Quality Criteria for Selenium (Freshwater). These documents include what the safe levels of Selenium are in water for the majority of species.

  5. Influence of short-term selenium supplementation on the natural course of Hashimoto's thyroiditis: clinical results of a blinded placebo-controlled randomized prospective trial.

    Science.gov (United States)

    Esposito, D; Rotondi, M; Accardo, G; Vallone, G; Conzo, G; Docimo, G; Selvaggi, F; Cappelli, C; Chiovato, L; Giugliano, D; Pasquali, D

    2017-01-01

    The real efficacy of selenium supplementation in Hashimoto's thyroiditis (HT) is still an unresolved issue. We studied the short-term effect of L-selenomethionine on the thyroid function in euthyroid patients with HT. Our primary outcome measures were TSH, thyroid hormones, thyroid peroxidase antibody (TPOAb), thyroglobulin antibody (TGAb) levels and thyroid echogenicity after 6 months of L-selenomethionine treatment. The secondary outcome measure was serum CXCL10 levels. In a placebo-controlled randomized prospective study, we have enrolled untreated euthyroid patients with HT. Seventy-six patients were randomly assigned to receive L-selenomethionine 166 µg/die (SE n = 38) or placebo (controls n = 38) for 6 months. TSH, free T4 (FT4), free T3 (FT3), TPOAb and CXCL10 serum levels were assayed at time 0, after 3 and 6 months. An ultrasound examination of the left and right thyroid lobe in transverse and longitudinal sections was performed. A rectangular region, the region of interest, was selected for analysis. TSH, FT4, FT3, TPOAb, thyroid echogenicity and CXCL10 were not statistically different between SE and control groups at time 0, after 3 and 6 months. In the SE group, FT4 levels were significantly decreased (P supplementation has a limited impact on the natural course in euthyroid HT. Our results tip the balance toward the ineffectiveness of short-term L-selenomethionine supplementation in HT.

  6. The Effect of Selenium Supplementation on DTH Skin Responses in Healthy North American Men

    Science.gov (United States)

    TThe essential nutrient selenium is required in microgram amounts (RDA=55 µg/d, 699 nmol/d) and has a narrow margin of safety (upper tolerable intake limit = 400 µg/d, 5080 nmol/d). We conducted a randomized placebo-controlled study of high-selenium yeast, the form used in most supplements, (300 µg/...

  7. Selenium in Cattle: A Review

    Directory of Open Access Journals (Sweden)

    Youcef Mehdi

    2016-04-01

    Full Text Available This review article examines the role of selenium (Se and the effects of Se supplementation especially in the bovine species. Selenium is an important trace element in cattle. Some of its roles include the participation in the antioxidant defense the cattle farms. The nutritional requirements of Se in cattle are estimated at 100 μg/kg DM (dry matter for beef cattle and at 300 μg/kg DM for dairy cows. The rations high in fermentable carbohydrates, nitrates, sulfates, calcium or hydrogen cyanide negatively influence the organism’s use of the selenium contained in the diet. The Se supplementation may reduce the incidence of metritis and ovarian cysts during the postpartum period. The increase in fertility when adding Se is attributed to the reduction of the embryonic death during the first month of gestation. A use of organic Se in feed would provide a better transfer of Se in calves relative to mineral Se supplementation. The addition of Se yeasts in the foodstuffs of cows significantly increases the Se content and the percentage of polyunsaturated fatty acids (PUFA in milk compared to the addition of sodium selenite. The enzyme 5-iodothyronine deiodinase is a seleno-dependent selenoprotein. It is one of the last proteins to be affected in the event of Se deficiency. This delay in response could explain the fact that several studies did not show the effect of Se supplementation on growth and weight gain of calves. Enrichment of Se in the diet did not significantly affect the slaughter weight and carcass yield of bulls. The impact and results of Se supplementation in cattle depend on physiological stage, Se status of animals, type and content of Se and types of Se administration. Further studies in Se supplementation should investigate the speciation of Se in food and yeasts, as well as understanding their metabolism and absorption. This constitute a path to exploit in order to explain certain different effects of Se.

  8. Selenium in Cattle: A Review.

    Science.gov (United States)

    Mehdi, Youcef; Dufrasne, Isabelle

    2016-04-23

    This review article examines the role of selenium (Se) and the effects of Se supplementation especially in the bovine species. Selenium is an important trace element in cattle. Some of its roles include the participation in the antioxidant defense the cattle farms. The nutritional requirements of Se in cattle are estimated at 100 μg/kg DM (dry matter) for beef cattle and at 300 μg/kg DM for dairy cows. The rations high in fermentable carbohydrates, nitrates, sulfates, calcium or hydrogen cyanide negatively influence the organism's use of the selenium contained in the diet. The Se supplementation may reduce the incidence of metritis and ovarian cysts during the postpartum period. The increase in fertility when adding Se is attributed to the reduction of the embryonic death during the first month of gestation. A use of organic Se in feed would provide a better transfer of Se in calves relative to mineral Se supplementation. The addition of Se yeasts in the foodstuffs of cows significantly increases the Se content and the percentage of polyunsaturated fatty acids (PUFA) in milk compared to the addition of sodium selenite. The enzyme 5-iodothyronine deiodinase is a seleno-dependent selenoprotein. It is one of the last proteins to be affected in the event of Se deficiency. This delay in response could explain the fact that several studies did not show the effect of Se supplementation on growth and weight gain of calves. Enrichment of Se in the diet did not significantly affect the slaughter weight and carcass yield of bulls. The impact and results of Se supplementation in cattle depend on physiological stage, Se status of animals, type and content of Se and types of Se administration. Further studies in Se supplementation should investigate the speciation of Se in food and yeasts, as well as understanding their metabolism and absorption. This constitute a path to exploit in order to explain certain different effects of Se.

  9. Selenium and Human Health

    Directory of Open Access Journals (Sweden)

    M Abedi

    2013-04-01

    Full Text Available Introduction: Selenium is an essential element for human health and it is toxic at high concentrations. Selenium is a constituent component of selenoproteins that have enzymatic and structural roles in human biochemistry. Selenium is a best antioxidant and catalyst for production of thyroid hormone. This element has the key role in the immune function; prevention of AIDS progression and the deactivity of toxins. Furthermore, selenium is essential for sperm motility and can reduce abortions. Selenium deficiency was also associated with adverse mood states. The findings regarding cardiovascular disease risk related to selenium deficiency is unclear, though other conditions such as vascular inflammation, oxidative stress and selenium deficiency can cause this disease too. Moreover, consuming of 60 mg of selenium per day may be associated with reduction of cancer risk. In this study, a review of studies has been performed on the biochemical function of selenium toxicity, and its effects on human health. Furthermore, certain identified cancers associated with selenium have been discussed to absorb more attention to the status of this element and also as a guide for further studies. Selenium plays the dual character (useful and harmful in human health, and then it is necessary to determine the concentration of this element in body fluids and tissues. An appropriate method for routine measurement of selenium in clinical laboratories is electro thermal atomic absorption spectrometry (ETAAS with very low detection limit and good precision.

  10. Association of selenium status and blood glutathione concentrations in blacks and whites

    Science.gov (United States)

    Richie, John P.; Muscat, Joshua E.; Ellison, Irina; Calcagnotto, Ana; Kleinman, Wayne; El-Bayoumy, Karam

    2011-01-01

    Selenium deficiency has been linked with increased cancer risk and, in some studies, selenium supplementation was protective against certain cancers. Previous studies suggest that selenium chemoprevention may involve reduced oxidative stress through enhanced glutathione (GSH). Our objectives were to examine the relationships between selenium and GSH in blood and modifying effects of race and sex in free living adults and individuals supplemented with selenium. Plasma selenium concentrations and free and bound GSH concentrations and γ-glutamyl cysteine ligase (GCL) activity in blood were measured in 336 healthy adults, (161 blacks, 175 whites). Plasma selenium and blood GSH were also measured in 36 healthy men from our previously conducted placebo-controlled trial of selenium-enriched yeast (247 μg/day for 9 months). In free-living adults, selenium concentrations were associated with increased blood GSH concentration and GCL activity (Pselenium was significantly higher in whites than in blacks (Psupplementation, plasma selenium was increased 114% in whites and 50% in blacks (Pselenium and GSH in blood of both free-living and selenium-supplemented individuals, with race being an important modifying factor. PMID:21462082

  11. Fecal selenium excretion is regulated by dietary selenium intake1

    OpenAIRE

    Pedrosa,Lucia Fatima Campos; Motley, Amy K.; Stevenson, Teri D.; Hill, Kristina E.; Burk, Raymond F.

    2012-01-01

    Whole-body selenium is regulated by excretion of the element. Reports of studies carried out using isotopic tracers have led to the conclusion that urinary selenium excretion is regulated by selenium intake but that fecal excretion is not. Because of the limitations of tracer studies, we measured urinary and fecal selenium excretion by mice with selenium intakes ranging from deficient to almost toxic. Tissue and whole-body selenium concentrations increased sharply between deficient and adequa...

  12. Selenium and the thyroid gland: more good news for clinicians.

    Science.gov (United States)

    Drutel, Anne; Archambeaud, Françoise; Caron, Philippe

    2013-02-01

    The thyroid is the organ with the highest selenium content per gram of tissue because it expresses specific selenoproteins. Since the discovery of myxoedematous cretinism and thyroid destruction following selenium repletion in iodine- and selenium-deficient children, data on links between thyroid metabolism and selenium have multiplied. Although very minor amounts of selenium appear sufficient for adequate activity of deiodinases, thus limiting the impact of its potential deficiency on synthesis of thyroid hormones, selenium status appears to have an impact on the development of thyroid pathologies. The value of selenium supplementation in autoimmune thyroid disorders has been emphasized. Most authors attribute the effect of supplementation on the immune system to the regulation of the production of reactive oxygen species and their metabolites. In patients with Hashimoto's disease and in pregnant women with anti-TPO antibodies, selenium supplementation decreases anti-thyroid antibody levels and improves the ultrasound structure of the thyroid gland. Although clinical applications still need to be defined for Hashimoto's disease, they are very interesting for pregnant women given that supplementation significantly decreases the percentage of postpartum thyroiditis and definitive hypothyroidism. In Graves' disease, selenium supplementation results in euthyroidism being achieved more rapidly and appears to have a beneficial effect on mild inflammatory orbitopathy. A risk of diabetes has been reported following long-term selenium supplementation, but few data are available on the side effects associated with such supplementation and further studies are required. © 2012 Blackwell Publishing Ltd.

  13. Biomonitoring Equivalents for selenium.

    Science.gov (United States)

    Hays, Sean M; Macey, Kristin; Nong, Andy; Aylward, Lesa L

    2014-10-01

    Selenium is an essential nutrient for human health with a narrow range between essentiality and toxicity. Selenium is incorporated into several proteins that perform important functions in the body. With insufficient selenium intake, the most notable effect is Keshan disease, an endemic cardiomyopathy in children. Conversely, excessive selenium intake can result in selenosis, manifested as brittle nails and hair and gastro-intestinal disorders. As such, guidance values have been established to protect against both insufficient and excessive selenium exposures. Dietary Reference Intakes (DRIs) have been established as standard reference values for nutritional adequacy in North America. To protect against selenosis resulting from exposure to excessive amounts of selenium, several government and non-governmental agencies have established a range of guidance values. Exposure to selenium is primarily through the diet, but monitoring selenium intake is difficult. Biomonitoring is a useful means of assessing and monitoring selenium status for both insufficient and excessive exposures. However, to be able to interpret selenium biomonitoring data, levels associated with both DRIs and toxicity guidance values are required. Biomonitoring Equivalents (BEs) were developed for selenium in whole blood, plasma and urine. The BEs associated with assuring adequate selenium intake (Estimated Average Requirements - EAR) are 100, 80 and 10μg/L in whole blood, plasma and urine, respectively. The BEs associated with protection against selenosis range from 400 to 480μg/L in whole blood, 180-230μg/L in plasma, and 90-110μg/L in urine. These BE values can be used by both regulatory agencies and public health officials to interpret selenium biomonitoring data in a health risk context. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Does selenium supplementation affect thyroid function? Results from a randomized, controlled, double-blinded trial in a Danish population.

    Science.gov (United States)

    Winther, Kristian Hillert; Bonnema, Steen Joop; Cold, Frederik; Debrabant, Birgit; Nybo, Mads; Cold, Søren; Hegedüs, Laszlo

    2015-06-01

    Selenium is present in the active site of proteins important for thyroid hormone synthesis and metabolism. The objective of this study is to investigate the effect of selenium supplementation in different doses on thyroid function, under conditions of suboptimal dietary selenium intake. The Danish PREvention of Cancer by Intervention with SElenium pilot study (DK-PRECISE) is a randomized, double-blinded, placebo-controlled trial. A total of 491 males and females aged 60-74 years were randomized to 100 μg (n=124), 200 μg (n=122), or 300 μg (n=119) selenium-enriched yeast or matching yeast-based placebo tablets (n=126). A total of 361 participants, equally distributed across treatment groups, completed the 5-year intervention period. Plasma samples were analyzed for selenium and serum samples for TSH, free triiodothyronine (FT3), and free thyroxine (FT4) at baseline, and after 6 months, and 5 years of supplementation. Plasma selenium concentrations increased significantly and dose-dependently in treatment groups receiving selenium (Pselenium supplementation minutely and dose-dependently affects thyroid function, when compared with placebo, by decreasing serum TSH and FT4 concentrations. Based on these findings, selenium supplementation is not warranted under conditions of marginal selenium deficiency. However, a role for selenium supplementation in the treatment of autoimmune thyroid diseases is still unresolved. © 2015 European Society of Endocrinology.

  15. Determination of total selenium and Se-77 in isotopically enriched human samples by ICP-dynamic reaction cell-MS

    DEFF Research Database (Denmark)

    Sloth, Jens Jørgen; Larsen, Erik Huusfeldt; Bügel, Susanne H.

    2003-01-01

    This paper describes an analytical method for the simultaneous quantitative determination of total selenium (Se) and Se-77 in isotopically enriched human plasma, urine and faeces by inductively coupled plasma- dynamic reaction cell- mass spectrometry ( ICP- DRC- MS). The samples originated from...... a human study in which a single dose of 327 mug Se-77 ( 99.3% pure) had been given as intrinsically Se-77-labelled yeast, following administration for six weeks of 300 mug d(-1) of selenium also as selenised yeast with natural isotope abundance. Prior to analysis, the plasma and urine samples...... and the digested faecal samples were diluted using an aqueous diluent containing 0.5% Triton X-100, 2% nitric acid and 3% methanol. Selenium was detected as Se-76, Se-77 and Se-80 by ICP- DRC- MS. Selenium originating from the natural isotope abundance yeast and other selenium sources from the diet was determined...

  16. Randomised clinical trial of parenteral selenium supplementation in preterm infants.

    OpenAIRE

    Daniels, L; Gibson, R.; Simmer, K.

    1996-01-01

    AIM: To determine whether selenium supplementation of parenteral nutrition with 3 micrograms/kg/day of selenious acid is safe and effective in improving the selenium status of preterm infants. METHODS: Thirty eight preterm infants with mean (SEM) birthweight of 1171 (38) g and gestational age 29 (0.3) weeks were randomly allocated to a non-supplemented (PN-selenium, n = 19) or supplemented (PN+selenium, n = 19) group. The study began at 2.8 (0.2) (range 1-5) days of age. Term breastfed (n = 2...

  17. Randomised controlled trial of the effect of long-term selenium supplementation on plasma cholesterol in an elderly Danish population

    DEFF Research Database (Denmark)

    Cold, Frederik; Winther, Kristian H; Pastor-Barriuso, Roberto

    2015-01-01

    Although cross-sectional studies have shown a positive association between Se and cholesterol concentrations, a recent randomised controlled trial in 501 elderly UK individuals of relatively low-Se status found that Se supplementation for 6 months lowered total plasma cholesterol. The Danish......:HDL-cholesterol ratio between intervention and placebo groups. The effect of long-term supplementation with Se on plasma cholesterol concentrations or its sub-fractions did not differ significantly from placebo in this elderly population....

  18. Selenium uptake and assessment of the biochemical changes in Arthrospira (Spirulina) platensis biomass during the synthesis of selenium nanoparticles.

    Science.gov (United States)

    Zinicovscaia, I; Chiriac, T; Cepoi, L; Rudi, L; Culicov, O; Frontasyeva, M; Rudic, V

    2017-01-01

    The process of selenium uptake by biomass of the cyanobacterium Arthrospira (Spirulina) platensis was investigated by neutron activation analysis at different selenium concentrations in solution and at different contact times. Experimental data showed good fit with the Freundlich adsorption isotherm model, with a regression coefficient value of 0.99. In terms of absorption dependence on time, the maximal selenium content was adsorbed in the first 5 min of interaction without significant further changes. It was also found that A. platensis biomass forms spherical selenium nanoparticles. Biochemical analysis was used to assess the changes in the main components of spirulina biomass (proteins, lipids, carbohydrates, and phycobilin) during nanoparticle formation.

  19. Selenium and human health.

    Science.gov (United States)

    Rayman, Margaret P

    2012-03-31

    Selenium is incorporated into selenoproteins that have a wide range of pleiotropic effects, ranging from antioxidant and anti-inflammatory effects to the production of active thyroid hormone. In the past 10 years, the discovery of disease-associated polymorphisms in selenoprotein genes has drawn attention to the relevance of selenoproteins to health. Low selenium status has been associated with increased risk of mortality, poor immune function, and cognitive decline. Higher selenium status or selenium supplementation has antiviral effects, is essential for successful male and female reproduction, and reduces the risk of autoimmune thyroid disease. Prospective studies have generally shown some benefit of higher selenium status on the risk of prostate, lung, colorectal, and bladder cancers, but findings from trials have been mixed, which probably emphasises the fact that supplementation will confer benefit only if intake of a nutrient is inadequate. Supplementation of people who already have adequate intake with additional selenium might increase their risk of type-2 diabetes. The crucial factor that needs to be emphasised with regard to the health effects of selenium is the inextricable U-shaped link with status; whereas additional selenium intake may benefit people with low status, those with adequate-to-high status might be affected adversely and should not take selenium supplements. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. A Novel Organic Selenium Compound Exerts Unique Regulation of Selenium Speciation, Selenogenome, and Selenoproteins in Broiler Chicks.

    Science.gov (United States)

    Zhao, Ling; Sun, Lv-Hui; Huang, Jia-Qiang; Briens, Mickael; Qi, De-Sheng; Xu, Shi-Wen; Lei, Xin Gen

    2017-05-01

    Background: A new organic selenium compound, 2-hydroxy-4-methylselenobutanoic acid (SeO), displayed a greater bioavailability than sodium selenite (SeNa) or seleno-yeast (SeY) in several species.Objective: This study sought to determine the regulation of the speciation of selenium, expression of selenogenome and selenocysteine biosynthesis and degradation-related genes, and production of selenoproteins by the 3 forms of selenium in the tissues of broiler chicks.Methods: Day-old male chicks (n = 6 cages/diet, 6 chicks/cage) were fed a selenium-deficient, corn and soy-based diet [base diet (BD), 0.05 mg Se/kg] or the BD + SeNa, SeY, or SeO at 0.2 mg Se/kg for 6 wk. Plasma, livers, and pectoral and thigh muscles were collected at weeks 3 and 6 to assay for total selenium, selenomethionine, selenocysteine, redox status, and selected genes, proteins, and enzymes.Results: Although both SeY and SeO produced greater concentrations (P selenium (20-172%) and of selenomethionine (≤15-fold) in the liver, pectoral muscle, and thigh than those of SeNa, SeO further raised (P selenium depositions, to induce the early expression of Selenos and Mrsb1 mRNA and TXRND activity, and to enhance the protein production of GPX4, SELENOP, and SELENOU in the tissues of chicks. © 2017 American Society for Nutrition.

  1. Inhibition of yeast growth during long term exposure to laser light around 1064 nm

    Science.gov (United States)

    Aabo, Thomas; Perch-Nielsen, Ivan R.; Dam, Jeppe Seidelin; Palima, Darwin Z.; Siegumfeldt, Henrik; Glückstad, Jesper; Arneborg, Nils

    2009-02-01

    We have studied the effect of a 1070 nm continuous wave Ytterbium fiber laser on exponentially growing Saccharomyces cerevisiae yeast cells over a span of 4 hours. The cells were immobilized onto Concanavalin A covered microscope slides and the growth was measured using the area increase of the cells in 2D. Using a continuous dual beam plane wave with a uniform spatial intensity distribution, we found that a continuous radiant flux through a single cell as low as 0.5 mW in 1.5 hours significantly changed the growth and division rate of S. cerevisiae. With the dual beam setup used we were able to successfully manipulate single S. cerevisiae cells in 3 dimensions with a minimum flux thorough the cell of 3.5 mW. In the regime investigated from 0.7 mW to 2.6 mW we found no threshold for the photo damage, but rather a continuous response to the increased accumulated dose.

  2. Deficient selenium status of a healthy adult Spanish population.

    Science.gov (United States)

    Millán Adame, E; Florea, D; Sáez Pérez, L; Molina López, J; López-González, B; Pérez de la Cruz, A; Planells del Pozo, E

    2012-01-01

    Selenium is an essential micronutrient for human health, being a cofactor for enzymes with antioxidant activity that protect the organism from oxidative damage. An inadequate intake of this mineral has been associated with the onset and progression of chronic diseases such as hypertension, diabetes, coronary diseases, asthma, and cancer. For this reason, knowledge of the plasma and erythrocyte selenium levels of a population makes a relevant contribution to assessment of its nutritional status. The objective of the present study was to determine the nutritional status of selenium and risk of selenium deficiency in a healthy adult population in Spain by examining food and nutrient intake and analyzing biochemical parameters related to selenium metabolism, including plasma and erythrocyte levels and selenium-dependent glutathione peroxidase (GPx) enzymatic activity. We studied 84 healthy adults (31 males and 53 females) from the province of Granada, determining their plasma and erythrocyte selenium concentrations and the association of these levels with the enzymatic activity of glutathione peroxidase (GPx) and with life style factors. We also gathered data on their food and nutrient intake and the results of biochemical analyses. Correlations were studied among all of these variables. The mean plasma selenium concentration was 76.6 ± 17.3 μg/L (87.3 ± 17.4 μg/L in males, 67.3 ± 10.7 μg/L in females), whereas the mean erythrocyte selenium concentration was 104.6 μg/L (107.9 ± 26.1 μg/L in males and 101.7 ± 21.7 μg/L in females). The nutritional status of selenium was defined by the plasma concentration required to reach maximum GPx activity, establishing 90 μg/L as reference value. According to this criterion, 50% of the men and 53% of the women were selenium deficient. Selenium is subjected to multiple regulation mechanisms. Erythrocyte selenium is a good marker of longer term selenium status, while plasma selenium appears to be a marker of short-term

  3. Selenium, selenoproteins and vision.

    Science.gov (United States)

    Flohé, Leopold

    2005-01-01

    Selenium biochemistry is reviewed in respect to its presumed relevance to age-related ocular diseases. Selenium is an essential trace element that exerts its physiological role as selenocysteine residue in at least 25 distinct selenoenzymes in mammals. Lack of GPx-1 due to alimentary selenium deprivation has been inferred to induce cataract in rats and was demonstrated to cause cataracts in mice by targeted gene disruption. The role of other selenoproteins in the eye remains to be worked out. Selenium in excess of the tiny amounts required for selenoprotein synthesis is toxic in general and causes cataracts in experimental animals. Clinical evidence for a protective role of selenium in the development of cataract, macula degeneration, retinitis pigmentosa or any other ocular disease is not available, likely because suboptimum selenium intake, as it may result from unbalanced diet, does not cause any pathologically relevant selenium deficiency in the eye. At present, there is neither theoretical nor an empirical basis to expect beneficial effects of selenium supplementation beyond the dietary reference intakes of 55 microg/day in the context of ocular diseases.

  4. Selenium in reproductive health.

    Science.gov (United States)

    Mistry, Hiten D; Broughton Pipkin, Fiona; Redman, Christopher W G; Poston, Lucilla

    2012-01-01

    Selenium is an essential trace element of importance to human biology and health. Increasing evidence suggests that this mineral plays an important role in normal growth and reproduction in animals and humans, and selenium supplementation is now recommended as part of public health policy in geographical areas with severe selenium deficiency in soil. This review addresses the biological functions of selenium followed by a detailed review of associations between selenium status and reproductive health. In many countries, selenium dietary intake falls below the recommended nutrient intakes and is inadequate to support maximal expression of the selenoenzymes. Numerous reports implicate selenium deficiency in several reproductive and obstetric complications including male and female infertility, miscarriage, preeclampsia, fetal growth restriction, preterm labor, gestational diabetes, and obstetric cholestasis. Currently, there is inadequate information from the available small intervention studies to inform public health strategies. Larger intervention trials are required to reinforce or refute a beneficial role of selenium supplementation in disorders of reproductive health. Copyright © 2012 Mosby, Inc. All rights reserved.

  5. Selenium and the thyroid.

    Science.gov (United States)

    Köhrle, Josef

    2015-10-01

    This article provides an update on the role of the essential trace element selenium and its interaction with the other trace elements iodine and iron that together contribute to adequate thyroid hormone status. Synthesis, secretion, metabolism and action of thyroid hormone in target tissues depend on a balanced nutritional availability or supplementation of these elements. Selenium status is altered in benign and malignant thyroid diseases and various selenium compounds have been used to prevent or treat widespread diseases such as goiter, autoimmune thyroid disease or thyroid cancer. Several studies, most with still too low numbers of cases, indicate that selenium administration in both autoimmune thyroiditis (Hashimoto thyroiditis) and mild Graves' disease improves clinical scores and well-being of patients and reduces thyroperoxidase antibody titers. However, published results are still conflicting depending on basal selenium status, dose, time and form of selenium used for intervention. Evidence for sex-specific selenium action, lack of beneficial effects in pregnancy and contribution of genetic polymorphisms (selenoprotein S) has been presented. Adequate nutritional supply of selenium that saturates expression of circulating selenoprotein P, together with optimal iodine and iron intake, is required for a healthy and functional thyroid during development, adolescence, adulthood and aging.

  6. SELENIUM MOBILITY IN SOME SOILS OF ROMANIA

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    Mihaela Lungu

    2013-12-01

    Full Text Available Selenium mobility in soil depends on a multitude of physical and chemical factors. The present paper highlights the selenium solubilization degree out of the total soil content in relation with its agrochemical properties. Soils samples were considered collected from different agricultural areas of the Country, with or without certain natural handicaps, from soils under industrial impact and long term agrochemical experiments. The selenium solubilization percentages out of the soil total content ranged between 3.57 and 8.15%. No solubilization percentage was calculated for Central and Southern Dobrudja and the South-Eastern Romanian Plane, because the total selenium quantities in these areas are lower and mobile selenium values are very low. The statistical analysis of the calculated percentage values highlighted homogeneous areas and areas with a higher scattering degree. Thus, in agricultural land, in acknowledged agrarian areas and in long term agricultural experiments, the percentage values are better grouped, showing (expectable soil homogeneousness, on one hand, and a significant soil selenium supply and its adequate solubilization for plant nutrition, on the other. The most scattered values occurred in the Călmăţui and Buzău valleys area in halomorphic soils, and in the Făgăraş Depression which is under the industrial polluting influence of chemical works. Among the causes for these differences is the uniformity or non-uniformity of the terrains, induced by land use and the existence or not of a handicap (polluting impact or halomorphic soils, for example. In general, there are no significant differences between the selenium mobility values and their grouping or scattering degree in the soil depth. A single exception stands out, namely in the Făgăraş Depression, where the selenium solubilization degree tends to increase with soil depth, as well as the scattering degree. In the Danube Delta diked areas Sireasa and Pardina very

  7. Improvement of Physiological Characteristic of Selenium-Enriched Candida utilis with Amino Acids Addition

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    Ge Xiaoguang

    2011-01-01

    Full Text Available The effects of amino acids addition on cell growth, glutathione biosynthesis, glutathione distribution, and the intracellular oxidation-reduction environment of Candida utilis SZU 07-01 during selenium enrichment were investigated in this study. Most amino acids under appropriate concentrations have positive effects on cell growth of the yeast strain, except for phenylalanine and proline, compared with the control without amino acid addition. The bioconversion of selenite to organic selenium induced the reduction of glutathione synthesis and intracellular distribution of glutathione. However, amino acids including cysteine, glutamine, glutamic acid, isoleucine, leucine, and tyrosine could effectively promote the selenium-enriched yeast to elevate glutathione production, especially increasing the intracellular glutathione content. Moreover, addition of these six different amino acids apparently decreased malondialdehyde concentration and recovered the normal intracellular redox environment of the selenium-enriched C. utilis SZU 07-01. The improvement of physiological characteristic of the selenium-enriched yeast by increasing intracellular glutathione content and lowering malondialdehyde content will undoubtedly help to widen application of selenium-enriched yeast as food or feed additives.

  8. Effects of maternal and dietary selenium (Se-enriched yeast) on the expression of Sel P and apoER2 of germ cells of their offspring in goats.

    Science.gov (United States)

    Wang, Qian; Shi, Lei; Ren, Youshe; Yue, Wenbin; Zhang, Chunxiang; Lei, Fulin

    2012-11-01

    In this experiment the effect of maternal dietary selenium on the expression of Sel P and apoER2 of goat offspring was studied. The experiment was conducted on 119 Taihang Black Goats randomly divided into 4 groups which were fed with a basal diet, supplemented with 0 (control), 0.5, 2 and 4 mg kg(-1) DM Se. Testis samples were collected from young male of each treatment group at the end of the study (30 d after weaning) for mRNA expression using real-time PCR and for protein expression by immunohistochemistry assay. A significant decrease was observed in mRNA expression of Sel P and apoER2 in the testis of the Se-deficient (Group 1) and the Se-excess (Group 4) compared with that in Groups 2 and 3. A similar trend of the protein expression of Sel P and apoER2 was also found. These data indicate that maternal and dietary selenium has an effect on the expression of Sel P and apoER2 in testis of their offspring. In addition, both groups were similar suggesting that the relationship between Sel P and apoER2, and apoER2 is a receptor of Sel P in the seminiferous epithelium to uptake the selenium. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. Erythrocyte selenium concentration as a marker of selenium status.

    Science.gov (United States)

    Stefanowicz, Fiona A; Talwar, Dinesh; O'Reilly, Denis S J; Dickinson, Natalie; Atkinson, John; Hursthouse, Andrew S; Rankin, Jean; Duncan, Andrew

    2013-10-01

    Plasma selenium concentration and glutathione peroxidase (GPx) activity are commonly used as markers of selenium nutritional status. However, plasma selenium concentrations fall independently of selenium status during the acute phase response and GPx is analytically problematic. The assay for erythrocyte selenium is robust and concentrations are unaffected by the systemic inflammatory response. This study was performed to investigate the validity of erythrocyte selenium measurement in assessing selenium status. C-reactive protein (CRP), plasma and erythrocyte selenium concentrations and GPx activity were measured in 96 women from two regions of Malawi with low and high selenium dietary intakes. CRP and plasma and erythrocyte selenium was measured in 91 critically ill patients with a systemic inflammatory response. The median CRP value of all subjects from Malawi was 4.2 mg/L indicating no inflammation. The median CRP value for the critically ill patients was 126 mg/L indicating this group was inflamed. In the non-inflamed population there was a strong positive correlation (r = 0.95) between erythrocyte and plasma selenium and a strong positive correlation (r = 0.77) between erythrocyte selenium and erythrocyte GPx up to 6.10 nmol/g Hb after which maximal activity was reached. In the inflamed population, plasma selenium was low, erythrocyte selenium was normal and there was a weak correlation (r = 0.30) between selenium concentrations in plasma and erythrocytes. This demonstrates that plasma selenium is affected by the inflammatory response while erythrocyte selenium concentration is unaffected and can be used to reliably assess selenium status across a wide range of selenium intakes. Copyright © 2013 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

  10. Selenium Enrichment of Horticultural Crops

    Directory of Open Access Journals (Sweden)

    Martina Puccinelli

    2017-06-01

    Full Text Available The ability of some crops to accumulate selenium (Se is crucial for human nutrition and health. Selenium has been identified as a cofactor of the enzyme glutathione peroxidase, which is a catalyzer in the reduction of peroxides that can damage cells and tissues, and can act as an antioxidant. Plants are the first link in the food chain, which ends with humans. Increasing the Se quantity in plant products, including leafy and fruity vegetables, and fruit crops, without exceeding the toxic threshold, is thus a good way to increase animal and human Se intake, with positive effects on long-term health. In many Se-enriched plants, most Se is in its major organic form. Given that this form is more available to humans and more efficient in increasing the selenium content than inorganic forms, the consumption of Se-enriched plants appears to be beneficial. An antioxidant effect of Se has been detected in Se-enriched vegetables and fruit crops due to an improved antioxidative status and to a reduced biosynthesis of ethylene, which is the hormone with a primary role in plant senescence and fruit ripening. This thus highlights the possible positive effect of Se in preserving a longer shelf-life and longer-lasting quality.

  11. Selenium Enrichment of Horticultural Crops.

    Science.gov (United States)

    Puccinelli, Martina; Malorgio, Fernando; Pezzarossa, Beatrice

    2017-06-04

    The ability of some crops to accumulate selenium (Se) is crucial for human nutrition and health. Selenium has been identified as a cofactor of the enzyme glutathione peroxidase, which is a catalyzer in the reduction of peroxides that can damage cells and tissues, and can act as an antioxidant. Plants are the first link in the food chain, which ends with humans. Increasing the Se quantity in plant products, including leafy and fruity vegetables, and fruit crops, without exceeding the toxic threshold, is thus a good way to increase animal and human Se intake, with positive effects on long-term health. In many Se-enriched plants, most Se is in its major organic form. Given that this form is more available to humans and more efficient in increasing the selenium content than inorganic forms, the consumption of Se-enriched plants appears to be beneficial. An antioxidant effect of Se has been detected in Se-enriched vegetables and fruit crops due to an improved antioxidative status and to a reduced biosynthesis of ethylene, which is the hormone with a primary role in plant senescence and fruit ripening. This thus highlights the possible positive effect of Se in preserving a longer shelf-life and longer-lasting quality.

  12. Mineral Commodity Profiles: Selenium

    Science.gov (United States)

    Butterman, W.C.; Brown, R.D.

    2004-01-01

    Overview -- Selenium, which is one of the chalcogen elements in group 16 (or 6A) of the periodic table, is a semiconductor that is chemically similar to sulfur for which it substitutes in many minerals and synthetic compounds. It is a byproduct of copper refining and, to a much lesser extent, lead refining. It is used in many applications, the major ones being a decolorizer for glass, a metallurgical additive to free-machining varieties of ferrous and nonferrous alloys, a constituent in cadmium sulfoselenide pigments, a photoreceptor in xerographic copiers, and a semiconductor in electrical rectifiers and photocells. Refined selenium amounting to more than 1,800 metric tons (t) was produced by 14 countries in 2000. Japan, Canada, the United States, and Belgium, which were the four largest producers, accounted for nearly 85 percent of world production. An estimated 250 t of the world total is secondary selenium, which is recovered from scrapped xerographic copier drums and selenium rectifiers; the selenium in nearly all other uses is dissipated (not recoverable as waste or scrap). The present selenium reserve bases for the United States and the world (including the United States), which are associated with copper deposits, are expected to be able to satisfy demand for selenium for several decades without difficulty.

  13. The fungistatic activity of organic selenium and its application to the production of cultivated mushrooms Agaricus bisporus and Pleurotus spp.

    Directory of Open Access Journals (Sweden)

    Savic Milena

    2012-01-01

    Full Text Available The activity of organic selenium against pathogenic molds and its use as a potential selenium source in the production of enriched mushrooms were examined. The effect of commercial selenized yeast on mycelia growth was examined using a method with mycelia disks and a well diffusion method. For mushroom enrichment, different concentrations of selenium were added to a growth substrate. The results presented in this paper suggest that the most suitable concentration of selenized yeast that inhibits the growth of the mycopathogenic molds is 70-100 mg/kg of selenium. With the addition of this concentration to the substrate, mushroom fruit bodies will uptake a high level of selenium, about 100 μg/g for Pleurotus spp., and 200 μg/g for Agaricus bisporus in dry weight of the mushroom. Thereby a double effect in the cultivation of mushrooms is achieved. [Projekat Ministarstva nauke Republike Srbije, br. III 46010 and br. III46001

  14. [Cadmium and selenium interaction in mammals].

    Science.gov (United States)

    Lazarus, Maja

    2010-09-01

    Cadmium occurs in the environment naturally and as a pollutant. Its exposure is inevitable and may produce toxic effects in many organs and organ systems through binding to biological structures, accumulation in internal organs or induction of free radical production. Another important aspect of Cd toxicity is its interaction, often anthagonistic, with essential elements. Vice versa, additional intake of the essential elements may have beneficial influence on distribution and toxic effects of cadmium. Selenium is an essential microelement and a constituent of many selenoproteins with antioxidant properties that bind cadmium (and other toxic elements such as mercury or arsenic). This review summarizes results, to date, of cadmium toxicokinetics and toxicodinamics, selenium biokinetics and biodinamics, as well as mechanisms of cadmium-selenium interaction and their impact on the oxidative status derived from the studies based upon mainly on animal experiments and on limited number of human studies. The wide variety of different doses, dose ratios, element administration modes and exposure lenghts of cadmium and selenium often yielded contradictory results. Future studies should be focused on assessment of effects of cadmium and selenium interaction in sensitive population groups and mechanisms of that interaction. Regarding animal studies, doses and exposure should be adjusted to long-term low exposure levels that are usually found in human population.

  15. Selenium in Graves' disease

    Directory of Open Access Journals (Sweden)

    Jadwiga Kryczyk

    2013-05-01

    Full Text Available The aim of this study was to present the current state of knowledge of the role of selenium in Graves’ disease. Recently, in the pathogenesis and course of this autoimmune disease, more attention has been paid to the relationship between oxidative stress and the antioxidant system, where selenium compounds play an important role. The thyroid is the organ with the highest selenium concentration in the human body. Selenium compounds, having antioxidant properties, protect thyrocytes against the destructive effects of reactive oxygen species (ROS, which are generated during the synthesis of thyroid hormones. Therefore, strengthening the body’s defense mechanisms, which protect against the formation and activity of ROS during medical treatment of Graves’ disease patients, may be an effective adjuvant in commonly used methods of therapy.

  16. Biological significance of selenium

    Energy Technology Data Exchange (ETDEWEB)

    Duerre, P.; Andreesen, J.R.

    1986-02-01

    Until a few years ago, selenium was exclusively thought of as a toxic substance which was applied mainly in the optical and electrical industries. By now, many biological reactions have been detected which cannot take place without the catalytic effect of selenium. The majority of these processes was found and clarified in microorganisms; however, the anticarcinogenic properties of this trace element may well have some significance for man in future.

  17. Effect of dietary selenium and omega-3 fatty acids on muscle composition and quality in broilers

    Directory of Open Access Journals (Sweden)

    Hetland Harald

    2007-10-01

    Full Text Available Abstract Background Human health may be improved if dietary intakes of selenium and omega-3 fatty acids are increased. Consumption of broiler meat is increasing, and the meat content of selenium and omega-3 fatty acids are affected by the composition of broiler feed. A two-way analyses of variance was used to study the effect of feed containing omega-3 rich plant oils and selenium enriched yeast on broiler meat composition, antioxidation- and sensory parameters. Four different wheat-based dietary treatments supplemented with 5% rapeseed oil or 4% rapeseed oil plus 1% linseed oil, and either 0.50 mg selenium or 0.84 mg selenium (organic form per kg diet was fed to newly hatched broilers for 22 days. Results The different dietary treatments gave distinct different concentrations of selenium and fatty acids in thigh muscle; one percent linseed oil in the diet increased the concentration of the omega-3 fatty acids 18:3, 20:5 and 22:5, and 0.84 mg selenium per kg diet gave muscle selenium concentration at the same level as is in fish muscle (0.39 mg/kg muscle. The high selenium intake also resulted in increased concentration of the long-chain omega-3 fatty acids EPA (20:5, DPA (22:5 and DHA (22:6, thus it may be speculated if high dietary selenium might have a role in increasing the concentration of EPA, DPA and DHA in tissues after intake of plant oils contning omega-3 fatty acids. Conclusion Moderate modifications of broiler feed may give a healthier broiler meat, having increased content of selenium and omega-3 fatty acids. High intakes of selenium (organic form may increase the concentration of very long-chain omega-3 fatty acids in muscle.

  18. Surveying selenium speciation from soil to cell - forms and transformations

    Energy Technology Data Exchange (ETDEWEB)

    Gammelgaard, Bente; Gabel-Jensen, Charlotte [University of Copenhagen, Department of Pharmaceutics and Analytical Chemistry, Faculty of Pharmaceutical Sciences, Copenhagen (Denmark); Jackson, Matthew I. [Grand Forks Human Nutrition Research Center, Agricultural Research Service, United States Department of Agriculture, Grand Forks, ND (United States)

    2011-02-15

    The aim of this review is to present and evaluate the present knowledge of which selenium species are available to the general population in the form of food and common supplements and how these species are metabolized in mammals. The overview of the selenium sources takes a horizontal approach, which encompasses identification of new metabolites in yeast and food of plant and animal origin, whereas the survey of the mammalian metabolism takes a horizontal as well as a vertical approach. The vertical approach encompasses studies on dynamic conversions of selenium compounds within cells, tissues or whole organisms. New and improved sample preparation, separation and detection methods are evaluated from an analytical chemical perspective to cover the progress in horizontal speciation, whereas the analytical methods for the vertical speciation and the interpretations of the results are evaluated from a biological angle as well. (orig.)

  19. Establishing optimal selenium status: results of a randomized, double-blind, placebo-controlled trial1234

    Science.gov (United States)

    Armah, Charlotte N; Dainty, Jack R; Hart, Dave J; Teucher, Birgit; Goldson, Andrew J; Broadley, Martin R; Motley, Amy K; Fairweather-Tait, Susan J

    2010-01-01

    Background: Dietary recommendations for selenium differ between countries, mainly because of uncertainties over the definition of optimal selenium status. Objective: The objective was to examine the dose-response relations for different forms of selenium. Design: A randomized, double-blind, placebo-controlled dietary intervention was carried out in 119 healthy men and women aged 50–64 y living in the United Kingdom. Daily placebo or selenium-enriched yeast tablets containing 50, 100, or 200 μg Se (≈60% selenomethionine), selenium-enriched onion meals (≈66% γ-glutamyl-methylselenocysteine, providing the equivalent of 50 μg Se/d), or unenriched onion meals were consumed for 12 wk. Changes in platelet glutathione peroxidase activity and in plasma selenium and selenoprotein P concentrations were measured. Results: The mean baseline plasma selenium concentration for all subjects was 95.7 ± 11.5 ng/mL, which increased significantly by 10 wk to steady state concentrations of 118.3 ± 13.1, 152.0 ± 24.3, and 177.4 ± 26.3 ng/mL in those who consumed 50, 100, or 200 μg Se-yeast/d, respectively. Platelet glutathione peroxidase activity did not change significantly in response to either dose or form of selenium. Selenoprotein P increased significantly in all selenium intervention groups from an overall baseline mean of 4.99 ± 0.80 μg/mL to 6.17 ± 0.85, 6.73 ± 1.01, 6.59 ± 0.64, and 5.72 ± 0.75 μg/mL in those who consumed 50, 100, or 200 μg Se-yeast/d and 50 μg Se-enriched onions/d, respectively. Conclusions: Plasma selenoprotein P is a useful biomarker of status in populations with relatively low selenium intakes because it responds to different dietary forms of selenium. To optimize the plasma selenoprotein P concentration in this study, 50 μg Se/d was required in addition to the habitual intake of ≈55 μg/d. In the context of established relations between plasma selenium and risk of cancer and mortality, and recognizing the important functions of

  20. Methods of Selenium Supplementation: Bioavailability and Determination of Selenium Compounds.

    Science.gov (United States)

    Bodnar, Malgorzata; Szczyglowska, Marzena; Konieczka, Piotr; Namiesnik, Jacek

    2016-01-01

    Selenium, a "dual-surface" element, maintains a very thin line between a level of necessity and harmfulness. Because of this, a deficiency or excess of this element in an organism is dangerous and causes health-related problems, both physically and mentally. The main source of selenium is a balanced diet, with a proper selection of meat and plant products. Meanwhile, the proper assimilation of selenium into these products depends on their bioavailability, bioaccessibility, and/or bioactivity of a given selenium compound. From the time when it was discovered that selenium and its compounds have a significant influence on metabolic processes and in many countries throughout the world, a low quantity of selenium was found in different parts of the environment, pressure was put upon an effective and fast method of supplementing the environment with the help of selenium. This work describes supplementation methods applied with the use of selenium, as well as new ideas for increasing the level of this element in various organisms. Based on the fact that selenium appears in the environment at trace levels, the determination of total amount of selenium or selenium speciation in a given sample demands the selection of appropriate measurement methods. These methods are most often comprised of a sample preparation technique and/or a separation technique as well as a detection system. The work presents information on the subject of analytical methods used for determining selenium and its compounds as well as examples in literature of their application.

  1. Aquatic Life Criterion - Selenium Documents

    Science.gov (United States)

    Documents pertaining to the 2016 Acute and Chronic Ambient Aquatic Life Water Quality Criteria for Selenium (Freshwater). These documents include what the safe levels of Selenium are in water for the majority of species.

  2. Effect of long term selenium yeast intervention on activity and gene expression of antioxidant and xenbiotic metabolising enzymes in healthy elderly volunteers from the Danish Prevention of Cancer by Intervention by Selenium (PRECISE) Pilot Study

    DEFF Research Database (Denmark)

    Ravn-Haren, Gitte; Krath, Britta; Overvad, Kim

    2008-01-01

    Numerous mechanisms have been proposed to explain the anti-carcinogenic effects of Se, among them altered carcinogen metabolism. We investigated the effect of Se supplementation on activities of glutathione peroxidase (GPX), glutathione reductase (GR) and glutathione S-transferase (GST) in differ...... genes could increase the risk of cancer. However, further studies are needed to establish whether the observed effect in leucocytes reflects a similar expression pattern in target tissues....

  3. Biological selenium removal from wastewaters

    NARCIS (Netherlands)

    Lenz, M.

    2008-01-01

    In this thesis, microbial conversion of water-soluble, highly toxic forms of selenium (selenate, selenite) to less bioavailable elemental selenium was investigated. By the exploitation of different groups of microorganisms (selenium-respiring, nitrate-reducing and sulfate-reducing bacteria,

  4. Selenium and redox signaling.

    Science.gov (United States)

    Brigelius-Flohé, Regina; Flohé, Leopold

    2017-03-01

    Selenium compounds that contain selenol functions or can be metabolized to selenols are toxic via superoxide and H2O2 generation, when ingested at dosages beyond requirement. At supra-nutritional dosages various forms of programmed cell death are observed. At physiological intakes, selenium exerts its function as constituent of selenoproteins, which overwhelmingly are oxidoreductases. Out of those, the glutathione peroxidases counteract hydroperoxide-stimulated signaling cascades comprising inflammation triggered by cytokines or lipid mediators, insulin signaling and different forms of programmed cell death. Similar events are exerted by peroxiredoxins, which functionally depend on the selenoproteins of the thioredoxin reductase family. The thiol peroxidases of both families can, however, also act as sensors for hydroperoxides, thereby initiating signaling cascades. Although the interaction of selenoproteins with signaling events has been established by genetic techniques, the in vivo relevance of these findings is still hard to delineate for several reasons: The biosynthesis of individual selenoproteins responds differently to variations of selenium intakes; selenium is preferentially delivered to privileged tissues via inter-organ trafficking and receptor-mediated uptake, and only half of the selenoproteins known by sequence have been functionally characterized. The fragmentary insights do not allow any uncritical use of selenium for optimizing human health. Copyright © 2016. Published by Elsevier Inc.

  5. Selenium for preventing cancer

    Science.gov (United States)

    Vinceti, Marco; Dennert, Gabriele; Crespi, Catherine M; Zwahlen, Marcel; Brinkman, Maree; Zeegers, Maurice PA; Horneber, Markus; D'Amico, Roberto; Del Giovane, Cinzia

    2015-01-01

    Background This review is an update of the first Cochrane publication on selenium for preventing cancer (Dennert 2011). Selenium is a metalloid with both nutritional and toxicological properties. Higher selenium exposure and selenium supplements have been suggested to protect against several types of cancers. Objectives Two research questions were addressed in this review: What is the evidence for: an aetiological relation between selenium exposure and cancer risk in humans? andthe efficacy of selenium supplementation for cancer prevention in humans? Search methods We conducted electronic searches of the Cochrane Central Register of Controlled Trials (CENTRAL, 2013, Issue 1), MEDLINE (Ovid, 1966 to February 2013 week 1), EMBASE (1980 to 2013 week 6), CancerLit (February 2004) and CCMed (February 2011). As MEDLINE now includes the journals indexed in CancerLit, no further searches were conducted in this database after 2004. Selection criteria We included prospective observational studies (cohort studies including sub-cohort controlled studies and nested case-control studies) and randomised controlled trials (RCTs) with healthy adult participants (18 years of age and older). Data collection and analysis For observational studies, we conducted random effects meta-analyses when five or more studies were retrieved for a specific outcome. For RCTs, we performed random effects meta-analyses when two or more studies were available. The risk of bias in observational studies was assessed using forms adapted from the Newcastle-Ottawa Quality Assessment Scale for cohort and case-control studies; the criteria specified in the Cochrane Handbook for Systematic Reviews of Interventions were used to evaluate the risk of bias in RCTs. Main results We included 55 prospective observational studies (including more than 1,100,000 participants) and eight RCTs (with a total of 44,743 participants). For the observational studies, we found lower cancer incidence (summary odds ratio (OR) 0

  6. Selenium Nanoparticles for Stress-Resilient Fish and Livestock

    Science.gov (United States)

    Sarkar, Biplab; Bhattacharjee, Surajit; Daware, Akshay; Tribedi, Prosun; Krishnani, K. K.; Minhas, P. S.

    2015-09-01

    The fisheries and livestock sectors capture the highest share of protein-rich animal food and demonstrate accelerated growth as an agriculture subsidiary. Environmental pollution, climate change, as well as pathogenic invasions exert increasing stress impacts that lead the productivity momentum at a crossroads. Oxidative stress is the most common form of stress phenomenon responsible for the retardation of productivity in fisheries and livestock. Essential micronutrients play a determinant role in combating oxidative stress. Selenium, one of the essential micronutrients, appears as a potent antioxidant with reduced toxicity in its nanoscale form. In the present review, different methods of synthesis and characterization of nanoscale selenium have been discussed. The functional characterization of nano-selenium in terms of its effect on growth patterns, feed digestibility, and reproductive system has been discussed to elucidate the mechanism of action. Moreover, its anti-carcinogenic and antioxidant potentiality, antimicrobial and immunomodulatory efficacy, and fatty acid reduction in liver have been deciphered as the new phenomena of nano-selenium application. Biologically synthesized nano-selenium raises hope for pharmacologically enriched, naturally stable nanoscale selenium with high ecological viability. Hence, nano-selenium can be administered with commercial feeds for improvising stress resilience and productivity of fish and livestock.

  7. Selenium in human mammary carcinogenesis

    DEFF Research Database (Denmark)

    Overvad, Kim; Grøn, P.; Langhoff, Otto

    1991-01-01

    In a case-referent study on the possible role of selenium in human mammary carcinogenesis, serum selenium was found to be 79 +/- 12 micrograms/l in 66 cases and 81 +/- 12 micrograms/l in 93 referents. An internal trend in serum selenium was observed among cases (TNM stage I 81 +/- 11 micrograms....../l and TNM stage II 76 +/- 13 micrograms selenium/l), indicating disease-mediated changes. The evaluation of selenium as a risk indicator in human breast cancer was therefore restricted to TNM stage I patients (n = 36). Multiple logistic regression analyses including variables associated with selenium levels...... revealed no association between selenium levels and breast cancer risk....

  8. Radioprotection by metals: Selenium

    Science.gov (United States)

    Weiss, J. F.; Srinivasan, V.; Kumar, K. S.; Landauer, M. R.

    The need exists for compounds that will protect individuals from high-dose acute radiation exposure in space and for agents that might be less protective but less toxic and longer acting. Metals and metal derivatives provide a small degree of radioprotection (dose reduction factor animal survival after whole-body irradiation). Emphasis is placed here on the radioprotective potential of selenium (Se). Both the inorganic salt, sodium selenite, and the organic Se compound, selenomethionine, enhance the survival of irradiated mice (60Co, 0.2 Gy/min) when injected IP either before (-24 hr and -1 hr) or shortly after (+15 min) radiation exposure. When administered at equitoxic doses (one-fourth LD10; selenomethionine = 4.0 mg/kg Se, sodium selenite = 0.8 mg/kg Se), both drugs enhanced the 30-day survival of mice irradiated at 9 Gy. Survival after 10-Gy exposure was significantly increased only after selenomethionine treatment. An advantage of selenomethionine is lower lethal and behavioral toxicity (locomotor activity depression) compared to sodium selenite, when they are administered at equivalent doses of Se. Sodium selenite administered in combination with WR-2721, S-2-(3-aminopropylamino)ethylphosphorothioic acid, enhances the radioprotective effect and reduces the lethal toxicity, but not the behavioral toxicity, of WR-2721. Other studies on radioprotection and protection against chemical carcinogens by different forms of Se are reviewed. As additional animal data and results from human chemoprevention trials become available, consideration also can be given to prolonged administration of Se compounds for protection against long-term radiation effects in space.

  9. A randomized trial of selenium supplementation and risk of type-2 diabetes, as assessed by plasma adiponectin.

    Directory of Open Access Journals (Sweden)

    Margaret P Rayman

    Full Text Available Evidence that selenium affects the risk of type-2 diabetes is conflicting, with observational studies and a few randomized trials showing both lower and higher risk linked to the level of selenium intake and status. We investigated the effect of selenium supplementation on the risk of type-2 diabetes in a population of relatively low selenium status as part of the UK PRECISE (PREvention of Cancer by Intervention with SElenium pilot study. Plasma adiponectin concentration, a recognised independent predictor of type-2 diabetes risk and known to be correlated with circulating selenoprotein P, was the biomarker chosen.In a randomized, double-blind, placebo-controlled trial, five hundred and one elderly volunteers were randomly assigned to a six-month intervention with 100, 200 or 300 µg selenium/d as high-selenium or placebo yeast. Adiponectin concentration was measured by ELISA at baseline and after six months of treatment in 473 participants with one or both plasma samples available.Mean (SD plasma selenium concentration was 88.5 ng/g (19.1 at baseline and increased significantly in the selenium-treatment groups. In baseline cross-sectional analyses, the fully adjusted geometric mean of plasma adiponectin was 14% lower (95% CI, 0-27% in the highest than in the lowest quartile of plasma selenium (P for linear trend = 0.04. In analyses across randomized groups, however, selenium supplementation had no effect on adiponectin levels after six months of treatment (P = 0.96.These findings are reassuring as they did not show a diabetogenic effect of a six-month supplementation with selenium in this sample of elderly individuals of relatively low selenium status.

  10. Immunomodulatory effect of selenosemicarbazides and selenium inorganic compounds, distribution in organs after selenium supplementation.

    Science.gov (United States)

    Musik, I; Koziol-Montewka, M; Toś-Luty, S; Pasternak, K; Latuszyńska, J; Tokarska, M; Kielczykowska, M

    1999-12-01

    Antioxidant properties of selenium producing a protective barrier against free radicals play an important role in numerous metabolic and immunologic processes associated with oxidation-reduction reactions which take place during intracellular digestion of phagocyted bacteria. The aim of our study was to examine the properties of an organic compound of selenium, 4-(o-tolilo)-selenosemicarbazide of p-chlorobenzoic acid in terms of its retention in organs, effect on erythropoesis and phagocytic abilities of neutrophiles as well as antioxidant properties in neutrophiles tested with NBT test. This compound as well as inorganic sodium selenate was given to Swiss mice at the dose of 10(-3) g Se/kg for the period of 10 days. The concentrations of selenium in livers of mice treated with sodium selenate and selenosemicarbazide were found to be higher than in controls (18.7 micrograms lg-1 and 23.2 micrograms lg-1 vs. 12 micrograms lg-1, respectively). Analysis of blood cells count has shown a significant decrease in neutrophile levels in both groups treated with selenium. The influence of selenium compounds on phagocytosis and especially NBT test has been determined (3.8% of positive cells in the controls vs. 2.2% and 0.9% in the groups treated with sodium selenate and selenosemicarbazide, respectively). Our preliminary investigations suggest that selenosemicarbazides are biologically active compounds and can modify neutrophile functions.

  11. FitSearch: a robust way to interpret a yeast fitness profile in terms of drug's mode-of-action.

    Science.gov (United States)

    Lee, Minho; Han, Sangjo; Chang, Hyeshik; Kwak, Youn-Sig; Weller, David M; Kim, Dongsup

    2013-01-01

    Yeast deletion-mutant collections have been successfully used to infer the mode-of-action of drugs especially by profiling chemical-genetic and genetic-genetic interactions on a genome-wide scale. Although tens of thousands of those profiles are publicly available, a lack of an accurate method for mining such data has been a major bottleneck for more widespread use of these useful resources. For general usage of those public resources, we designed FitRankDB as a general repository of fitness profiles, and developed a new search algorithm, FitSearch, for identifying the profiles that have a high similarity score with statistical significance for a given fitness profile. We demonstrated that our new repository and algorithm are highly beneficial to researchers who attempting to make hypotheses based on unknown modes-of-action of bioactive compounds, regardless of the types of experiments that have been performed using yeast deletion-mutant collection in various types of different measurement platforms, especially non-chip-based platforms. We showed that our new database and algorithm are useful when attempting to construct a hypothesis regarding the unknown function of a bioactive compound through small-scale experiments with a yeast deletion collection in a platform independent manner. The FitRankDB and FitSearch enhance the ease of searching public yeast fitness profiles and obtaining insights into unknown mechanisms of action of drugs. FitSearch is freely available at http://fitsearch.kaist.ac.kr.

  12. [Selenium content in human in Sakha Republic].

    Science.gov (United States)

    Golubkina, N A; Senkevich, O A; Kekina, E G

    2009-01-01

    Sakha Republic is considered to be endemic selenium deficient and poorly investigated region. Analysis of selenium in human sera, hair and nails revealed strongly decreased values. Low selenium concentrations were registered also in meat of domestic animals, fresh-water fish, mushrooms weight, agaricus campester. The possibility of the human selenium content improvement is discussed via import of grain with high selenium concentration.

  13. Lithium as a prooxidant? A possible protective role of selenium – in vitro study

    Directory of Open Access Journals (Sweden)

    Irena Musik

    2017-09-01

    In Vero cells lithium decreased all studied parameters, particularly GPx. Selenium co-treatment showed a distinct protective effect. In FaDu cells the similar effect was observed only in case of GSH. The results point to differences in action of lithium and selenium in physiological and pathological state. As long-term lithium therapy is applied in psychiatric patients the results regarding Vero line let suggest that selenium might be considered as an adjuvant alleviating side effects of Li-treatment.

  14. Optimising Selenium for Modulation of Cancer Treatments.

    Science.gov (United States)

    Evans, Stephen Owen; Khairuddin, Puteri Farisa; Jameson, Michael B

    2017-12-01

    Selenium is an essential trace element involved in many biological processes that are mediated through, at least, 25 selenoproteins expressed in humans. Extensive study of selenium compounds has demonstrated growth inhibition of malignant cells in a vast array of experimental models. Moreover combining selenium with conventional cancer therapy has yielded promising results in both preclinical studies and a cohort of human trials. The aim of this review is to highlight the current research evaluating the role of selenium compounds in combination with chemotherapy and radiation. Pharmacodymanic mechanisms responsible for the differential effects of the commonly studied compounds on healthy and malignant cells are presented and the pertinent in vitro and in vivo data summarised. The clinical utility of this approach is discussed both in terms of anti-tumour efficacy and toxicity prevention. Finally a case is made for novel trial designs to facilitate rapid progression into pivotal studies. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  15. Biomarkers of selenium status

    Science.gov (United States)

    The essential trace element selenium (Se) has multiple biological activities, which depend on the level of Se intake. Relatively low Se intakes determine the expression of selenoenzymes in which it serves as an essential constituent. Higher intakes have been shown to have anti-tumorigenic potentia...

  16. Selenium Treatment Technologies

    Science.gov (United States)

    Selenium (Se) is a metalloid that is a dietary requirement in small quantities, but toxic at higher quantities. It also is known to bioaccumulate. In oxic environments, it exists as selenate (+6) and selenite (+4), both of which are soluble. Selenite will sorb more strongly to...

  17. Concentration-Dependent Effects of Rhodiola Rosea on Long-Term Survival and Stress Resistance of Yeast Saccharomyces Cerevisiae: The Involvement of YAP 1 and MSN2/4 Regulatory Proteins.

    Science.gov (United States)

    Bayliak, Maria M; Burdyliuk, Nadia I; Izers'ka, Lilia I; Lushchak, Volodymyr I

    2014-01-01

    Concentration-dependent effects of aqueous extract from R. rosea root on long-term survival and stress resistance of budding yeast Saccharomyces cerevisiae were studied. At low concentrations, R. rosea aqueous extract extended yeast chronological lifespan, enhanced oxidative stress resistance of stationary-phase cells and resistance to number stressors in exponentially growing cultures. At high concentrations, R. rosea extract sensitized yeast cells to stresses and shortened yeast lifespan. These biphasic concentration-responses describe a common hormetic phenomenon characterized by a low-dose stimulation and a high-dose inhibition. Yeast pretreatment with low doses of R. rosea extract enhanced yeast survival and prevented protein oxidation under H2O2-induced oxidative stress. Positive effect of R. rosea extract on yeast survival under heat shock exposure was not accompanied with changes in antioxidant enzyme activities and levels of oxidized proteins. The deficiency in transcriptional regulators, Msn2/Msn4 and Yap1, abolished the positive effect of low doses of R. rosea extract on yeast viability under stress challenges. Potential involvement of Msn2/Msn4 and Yap1 regulatory proteins in realization of R. rosea beneficial effects is discussed.

  18. Selenium Metabolism in Cancer Cells: The Combined Application of XAS and XFM Techniques to the Problem of Selenium Speciation in Biological Systems

    Directory of Open Access Journals (Sweden)

    Hugh H. Harris

    2013-05-01

    Full Text Available Determining the speciation of selenium in vivo is crucial to understanding the biological activity of this essential element, which is a popular dietary supplement due to its anti-cancer properties. Hyphenated techniques that combine separation and detection methods are traditionally and effectively used in selenium speciation analysis, but require extensive sample preparation that may affect speciation. Synchrotron-based X-ray absorption and fluorescence techniques offer an alternative approach to selenium speciation analysis that requires minimal sample preparation. We present a brief summary of some key HPLC-ICP-MS and ESI-MS/MS studies of the speciation of selenium in cells and rat tissues. We review the results of a top-down approach to selenium speciation in human lung cancer cells that aims to link the speciation and distribution of selenium to its biological activity using a combination of X-ray absorption spectroscopy (XAS and X-ray fluorescence microscopy (XFM. The results of this approach highlight the distinct fates of selenomethionine, methylselenocysteine and selenite in terms of their speciation and distribution within cells: organic selenium metabolites were widely distributed throughout the cells, whereas inorganic selenium metabolites were compartmentalized and associated with copper. New data from the XFM mapping of electrophoretically-separated cell lysates show the distribution of selenium in the proteins of selenomethionine-treated cells. Future applications of this top-down approach are discussed.

  19. Selenium Level and Dyslipidemia in Rural Elderly Chinese

    Science.gov (United States)

    Su, Liqin; Gao, Sujuan; Unverzagt, Frederick W.; Cheng, Yibin; Hake, Ann M.; Xin, Pengju; Chen, Chen; Liu, Jingyi; Ma, Feng; Bian, Jianchao; Li, Ping; Jin, Yinlong

    2015-01-01

    Objective Higher selenium level has been hypothesized to have the potential to reduce the risk of cardiovascular diseases including dyslipidemia. However, results from previous studies are inconsistent. This study aims to determine the association between selenium level and dyslipidemia in elderly Chinese with relatively low selenium status. Methods A cross-sectional study of 1859 participants aged 65 or older from four rural counties in China was conducted. Serum total cholesterol (TC), triglycerides (TG), high density lipoprotein-cholesterol (HDLC) and low-density lipoprotein-cholesterol (LDLC), nail selenium concentration and APOE genotype were measured in all subjects. The four types of dyslipidemia were defined as >5.17mmol/L for High-TC, >1.69 mmol/L for High-TG, >3.36 mmol/L for High-LDLC, and selenium levels and the risk of dyslipidemia. Results Mean nail selenium concentration was 0.465μg/gin this sample. Rates for High-TC, High-LDLC, High-TG, Low-HDLC were 18.13%, 13.23%, 12.21% and 32.76% respectively. Results from logistic models indicated that higher selenium levels were significantly associated with higher risk of High-TC, High-LDLC and lower risk of Low-HDLC adjusting for covariates (p selenium quartile group, participants in selenium quartile groups 2, 3 and 4 had significantly higher rates of High-TC, High-LDLC, High-TG, and lower rate of Low-HDLC adjusting for covariates. No significant association was observed between selenium level and the risk of High-TG. APOEε4 carriers had higher rates of High-TC and High-LDLC. There was no interaction between selenium level and APOE with the rates of dyslipidemia. Conclusions Our results suggest long-term selenium exposure level may be associated with the risk of dyslipidemia in elderly population. Future studies are needed to examine the underlying mechanism of the association. PMID:26380972

  20. Selenium Level and Dyslipidemia in Rural Elderly Chinese.

    Directory of Open Access Journals (Sweden)

    Liqin Su

    dyslipidemia.Our results suggest long-term selenium exposure level may be associated with the risk of dyslipidemia in elderly population. Future studies are needed to examine the underlying mechanism of the association.

  1. Supplementation with Selenium and Coenzyme Q10 Reduces Cardiovascular Mortality in Elderly with Low Selenium Status. A Secondary Analysis of a Randomised Clinical Trial.

    Science.gov (United States)

    Alehagen, Urban; Alexander, Jan; Aaseth, Jan

    2016-01-01

    Selenium is needed by all living cells in order to ensure the optimal function of several enzyme systems. However, the selenium content in the soil in Europe is generally low. Previous reports indicate that a dietary supplement of selenium could reduce cardiovascular disease but mainly in populations in low selenium areas. The objective of this secondary analysis of a previous randomised double-blind placebo-controlled trial from our group was to determine whether the effects on cardiovascular mortality of supplementation with a fixed dose of selenium and coenzyme Q10 combined during a four-year intervention were dependent on the basal level of selenium. In 668 healthy elderly individuals from a municipality in Sweden, serum selenium concentration was measured. Of these, 219 individuals received daily supplementation with selenium (200 μg Se as selenized yeast) and coenzyme Q10 (200 mg) combined for four years. The remaining participants (n = 449) received either placebo (n = 222) or no treatment (n = 227). All cardiovascular mortality was registered. No participant was lost during a median follow-up of 5.2 years. Based on death certificates and autopsy results, all mortality was registered. The mean serum selenium concentration among participants at baseline was low, 67.1 μg/L. Based on the distribution of selenium concentration at baseline, the supplemented group was divided into three groups; 85 μg/L (45 and 90 percentiles) and the remaining participants were distributed accordingly. Among the non-treated participants, lower cardiovascular mortality was found in the high selenium group as compared with the low selenium group (13.0% vs. 24.1%; P = 0.04). In the group with the lowest selenium basal concentration, those receiving placebo or no supplementation had a mortality of 24.1%, while mortality was 12.1% in the group receiving the active substance, which was an absolute risk reduction of 12%. In the middle selenium concentration group a mortality of 14

  2. Phase III randomised chemoprevention study with selenium on the recurrence of non-invasive urothelial carcinoma. The SELEnium and BLAdder cancer Trial.

    Science.gov (United States)

    Goossens, Maria E; Zeegers, Maurice P; van Poppel, Hendrik; Joniau, Steven; Ackaert, Koen; Ameye, Filip; Billiet, Ignace; Braeckman, Johan; Breugelmans, Alex; Darras, Jochen; Dilen, Kurt; Goeman, Lieven; Tombal, Bertrand; Van Bruwaene, Siska; Van Cleyenbreugel, Ben; Van der Aa, Frank; Vekemans, Kris; Buntinx, Frank

    2016-12-01

    In Belgium, bladder cancer (BC) is the fifth most common cancer in men. The per-patient lifetime cost is high. Previous epidemiological studies have consistently reported that selenium concentrations were inversely associated with the risk of BC. We therefore hypothesised that selenium may be suitable for chemoprevention of recurrence of BC. The Selenium and Bladder Cancer Trial (SELEBLAT) was an academic phase III placebo-controlled, double-blind, randomised clinical trial designed to determine the effect of selenium on recurrence of non-invasive urothelial carcinoma conducted in 14 Belgian hospitals. Patients were randomly assigned by a computer program to oral selenium yeast 200 μg once a day or placebo for three years, in addition to standard care. All study personnel and participants were blinded to treatment assignment for the duration of the study. All randomised patients were included in the intention to treat (ITT) and safety analyses. Per protocol analyses (PPAs) included all patients in the study three months after start date. Between September 18, 2009 and April 18, 2013, 151 and 141 patients were randomised in the selenium and placebo group. Patients were followed until December 31, 2015. The ITT analysis resulted in 43 (28%; 95% CI, 0.21-0.35) and 45 (32%; 95% CI, 0.24-0.40) recurrences in the selenium and placebo group. The hazard ratio (HR) was 0.85 (95% CI, 0.56-1.29; p = 0.44) while the HR for the PPA resulted in 42 and 39 (28%; 95% CI, 0.20-0.35) recurrences in the selenium and placebo group (HR = 0.96 [95% CI, 0.62-1.48]; p = 0.93). Selenium supplementation does not lower the probability of recurrence in BC patients. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Selenium and ocular health in New Zealand.

    Science.gov (United States)

    Sheck, Leo; Davies, Jo; Wilson, Graham

    2010-06-11

    Selenium is an essential mineral and severe selenium deficiency is known to cause significant health problems. It has been well documented that New Zealand soil is low in selenium. Recent studies have addressed the roles of selenoproteins in the eyes, with evidence suggesting that selenium supplementation may have a role in preventing cataract formation and age-related maculopathy. This paper summarises the role of selenium in ocular and general health and discusses selenium supplementation in a New Zealand specific context.

  4. New Strategy for Prostate Cancer Prevention Based on Selenium Suppression of Androgen Receptor Signaling

    Science.gov (United States)

    2010-04-01

    5α-reductase inhibitor; prostate cancer; chemoprevention; androgen receptor; FOXO1 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT...influences comparative activity of selenium-enriched garlic and yeast in mammary cancer pre- vention. J Agric Food Chem 2000;48(6):2062–2070. 12. Medina D

  5. Dietary Selenium and Human Health

    Directory of Open Access Journals (Sweden)

    Lutz Schomburg

    2016-12-01

    Full Text Available Next year (2017, the micronutrient Selenium (Se is celebrating its birthday—i.e., 200 years after first being identified by the Swedish chemist Jöns Jakob Berzelius. Despite its impressive age, research into the functions of this essential trace element is very alive and reaching out for new horizons. This special issue presents some recent fascinating, exciting, and promising developments in Se research in the form of eight original contributions and seven review articles. Collectively, aspects of Se supply, biochemical, physiological, and chemotherapeutic effects, and geobiological interactions are covered by leading scientists in the areas of nutritional, basic, and clinical research. It is obvious from the contributions that the bicentennial anniversary will celebrate a micronutrient still in its infancy with respect to being understood in terms of its biomedical importance.

  6. Dietary Selenium and Human Health.

    Science.gov (United States)

    Schomburg, Lutz

    2016-12-30

    Next year (2017), the micronutrient Selenium (Se) is celebrating its birthday-i.e., 200 years after first being identified by the Swedish chemist Jöns Jakob Berzelius. Despite its impressive age, research into the functions of this essential trace element is very alive and reaching out for new horizons. This special issue presents some recent fascinating, exciting, and promising developments in Se research in the form of eight original contributions and seven review articles. Collectively, aspects of Se supply, biochemical, physiological, and chemotherapeutic effects, and geobiological interactions are covered by leading scientists in the areas of nutritional, basic, and clinical research. It is obvious from the contributions that the bicentennial anniversary will celebrate a micronutrient still in its infancy with respect to being understood in terms of its biomedical importance.

  7. Selenium in food and health

    National Research Council Canada - National Science Library

    Reilly, Conor

    2006-01-01

    ...) to be a carcinogen and banned as an additive in food. Selenium is considered by some to be a serious hazard to the environment and to animal health. Selenium-contaminated water has brought deformity and death to wildlife in nature reserves in western USA. There is even concern that because of selenium contamination of soil, crops supplied to the great cities of California could become unfit for human consumption. In large areas of China, endemic selenium toxicity is a hazard for locals who depend on cr...

  8. Biogenesis of Selenium Nanoparticles Using Green Chemistry.

    Science.gov (United States)

    Shoeibi, Sara; Mozdziak, Paul; Golkar-Narenji, Afsaneh

    2017-11-09

    Selenium binds some enzymes such as glutathione peroxidase and thioredoxin reductase, which may be activated in biological infections and oxidative stress. Chemical and physical methods for synthesizing nanoparticles, apart from being expensive, have their own particular risks. However, nanoparticle synthesis through green chemistry is a safe procedure that different biological sources such as bacteria, fungi, yeasts, algae and plants can be the catalyst bed for processing. Synthesis of selenium nanoparticles (SeNPs) by macro/microorganisms causes variation in morphology and shape of the particles is due to diversity of reduction enzymes in organisms. Reducing enzymes of microorganisms by changing the status of redox convert metal ions (Se 2- ) to SeNPs without charge (Se 0 ). Biological activity of SeNPs includes their protective role against DNA oxidation. Because of the biological and industrial properties, SeNPs have wide applications in the fields of medicine, microelectronic, agriculture and animal husbandry. SeNPs can show strong antimicrobial effects on the growth and proliferation of microorganisms in a dose-dependent manner. The objective of this review is to consider SeNPs applications to various organisms.

  9. Designing the selenium and bladder cancer trial (SELEBLAT, a phase lll randomized chemoprevention study with selenium on recurrence of bladder cancer in Belgium

    Directory of Open Access Journals (Sweden)

    Goossens Maria E

    2012-03-01

    Full Text Available Abstract Background In Belgium, bladder cancer is the fifth most common cancer in males (5.2% and the sixth most frequent cause of death from cancer in males (3.8%. Previous epidemiological studies have consistently reported that selenium concentrations were inversely associated with the risk of bladder cancer. This suggests that selenium may also be suitable for chemoprevention of recurrence. Method The SELEBLAT study opened in September 2009 and is still recruiting all patients with non-invasive transitional cell carcinoma of the bladder on TURB operation in 15 Belgian hospitals. Recruitment progress can be monitored live at http://www.seleblat.org. Patients are randomly assigned to selenium yeast (200 μg/day supplementation for 3 years or matching placebo, in addition to standard care. The objective is to determine the effect of selenium on the recurrence of bladder cancer. Randomization is stratified by treatment centre. A computerized algorithm randomly assigns the patients to a treatment arm. All study personnel and participants are blinded to treatment assignment for the duration of the study. Design The SELEnium and BLAdder cancer Trial (SELEBLAT is a phase III randomized, placebo-controlled, academic, double-blind superior trial. Discussion This is the first report on a selenium randomized trial in bladder cancer patients. Trial registration ClinicalTrials.gov identifier: NCT00729287

  10. Maternal selenium status during early gestation and risk for preterm birth

    NARCIS (Netherlands)

    Rayman, Margaret P.; Wijnen, Hennie; Vader, Huib; Kooistra, Libbe; Pop, Victor

    2011-01-01

    Background: Preterm birth occurs in 5%-13% of pregnancies. It is a leading cause of perinatal mortality and morbidity and has adverse long-term consequences for the health of the child. Because of the role selenium plays in attenuating inflammation, and because low concentrations of selenium have

  11. Binary mixtures of mercury/ selenium, and lead/selenium

    African Journals Online (AJOL)

    Physiologically-based biokinetic models have been developed for predicting simultaneously the Absorption, Distribution, Metabolism and Elimination (ADME) properties of lead (Pb) and selenium (Se), and mercury (Hg) and selenium in a number of target tissues of humans. This was done for three population groups, ...

  12. Microbial selenium sulfide reduction for selenium recovery from wastewater

    NARCIS (Netherlands)

    Hageman, S.P.W.; Weijden, van der R.D.; Stams, A.J.M.; Cappellen, van P.; Buisman, C.J.N.

    2017-01-01

    Microbial reduction of selenium sulfide (SeS2) is a key step in a new treatment process to recover selenium from selenate and selenite streams. In this process, selenate is first reduced to selenite, and subsequently selenite is reduced by sulfide and precipitates from the solution as SeS2. The

  13. Long-Term Imaging of DNA Damage and Cell Cycle Progression in Budding Yeast Using Spinning Disk Confocal Microscopy.

    Science.gov (United States)

    Montecchi, Riccardo; Schwob, Etienne

    2018-01-01

    Live cell imaging can monitor biological processes in time and space by providing quantitative measurements of cell behavior on a single-cell basis and in live conditions. However the illumination required to visualize fluorescently tagged endogenous proteins often perturbs cellular physiology, a problem particularly acute for yeast cells that are small, highly photosensitive and with scarce protein content. Analyzing the activation of the DNA damage response (DDR) in various yeast mutants or growth conditions, as well as its consequences for cell cycle progression and cell viability over extended periods of time therefore requires a special microscopy setup that does not by itself create DNA damage or perturb cell growth. Here, we provide a quick guide, strains and advice for imaging the DDR in S. cerevisiae for extended time (3-12 h) using spinning-disk confocal microscopy in conditions of limited photobleaching and photodamage. DDR is a conserved mechanism that allows the cell to respond to various stresses, especially those altering DNA integrity or topology. Acquiring time-lapse images of the DDR at high temporal and spatial resolution is of great interest, in particular when studying the effects of mutations or drugs which compromise genomic stability and cell cycle progression.

  14. Selenium enrichment of table eggs.

    Science.gov (United States)

    Bennett, D C; Cheng, K M

    2010-10-01

    Selenium is an essential trace element with a recommended dietary allowance for human adults of 55 μg/d. However, there is evidence that greater dietary intakes may have possible health benefits, including a reduction in the risk of cancer. Several studies have shown the feasibility of enriching eggs using organic Se and that Se-enriched eggs are an effective way to supplement human diets. However, few studies have examined the response of egg Se concentration to high (>1 μg/g) dietary organic Se intake by the laying hens. The objective of the current study is to examine the effect of higher dietary organic Se levels on production, egg mass, and egg Se levels. These were assessed by feeding 3 breeds of laying hens (Barred Plymouth Rock, Lohmann Brown, Lohmann White) a basal diet containing 0.3 μg of Se/g of diet as Na2SeO3. Into this diet, Se yeast (SelenoSource AF 600), an organic source of Se, was added at 1.0, 2.4, or 5.1 μg of Se/g of diet for 4 wk. Feed consumption, egg production, and egg mass were not affected by the dietary Se concentration in all 3 breeds. Within the range of Se levels employed in the laying hens' diet, egg Se content increased linearly as dietary levels of Se increased. The results of this study indicate that feeding up to 5.1 µg/g of Se will not affect egg production and the welfare of the laying hen and is a practical way of producing Se-enriched eggs for the consumers.

  15. Selenium Supplementation for Prevention of Colorectal Adenomas and Risk of Associated Type 2 Diabetes.

    Science.gov (United States)

    Thompson, Patricia A; Ashbeck, Erin L; Roe, Denise J; Fales, Liane; Buckmeier, Julie; Wang, Fang; Bhattacharyya, Achyut; Hsu, Chiu-Hsieh; Chow, H H Sherry; Ahnen, Dennis J; Boland, C Richard; Heigh, Russell I; Fay, David E; Hamilton, Stanley R; Jacobs, Elizabeth T; Martinez, Maria Elena; Alberts, David S; Lance, Peter

    2016-12-01

    Selenium supplementation may help to prevent colorectal cancer; as precursors of colorectal cancer, colorectal adenomas are a surrogate for colorectal cancer. Selenium supplementation may increase risk of type 2 diabetes (T2D). The Selenium and Celecoxib (Sel/Cel) Trial was a randomized, placebo controlled trial of selenium 200 µg daily as selenized yeast and celecoxib 400 mg once daily, alone or together, for colorectal adenoma prevention. Men and women between age 40 and 80 years were eligible following colonoscopic removal of colorectal adenomas. The primary outcome was adenoma development. Celecoxib was suspended because of cardiovascular toxicity in other trials, but accrual continued to selenium and placebo. A total of 1621 participants were randomly assigned to selenium or placebo, of whom 1374 (84.8%) were available for analysis. All statistical tests were two-sided. In the respective placebo and selenium arms of 689 and 685 participants, adenoma detection after medians of 33.6 (range = 0.0-85.1 months) and 33.0 months (range = 0.0-82.6 months) were 42.8% and 44.1% (relative risk [RR] = 1.03, 95% confidence interval [CI] = 0.91 to 1.16, P = .68). In participants with baseline advanced adenomas, adenoma recurrence was reduced by 18% with selenium (RR = 0.82, 95% CI = 0.71 to 0.96, P = .01). In participants receiving selenium, the hazard ratio for new-onset T2D was 1.25 (95% CI = 0.74 to 2.11, P = .41), with a statistically significantly increased risk of selenium-associated T2D among older participants (RR = 2.21; 95% CI = 1.04 to 4.67, P = .03). Overall, selenium did not prevent colorectal adenomas and showed only modest benefit in patients with baseline advanced adenomas. With limited benefit and similar increases in T2D to other trials, selenium is not recommended for preventing colorectal adenomas in selenium-replete individuals. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please

  16. EFFECT OF SELENIUM SUPPLEMENTATION ON PIG PRODUCTION PROPERTIES, ANTIOXIDANT STATUS AND MEAT QUALITY

    Directory of Open Access Journals (Sweden)

    Tomislav Šperanda

    2013-12-01

    dark fibers with 0.5 ppm organic selenium dietary addition (P2 was determined in relation to the control. All groups fed higher selenium concentration had more oxidative fibers which affect on slower pH drop, less lactate and less pale, soft and exudative pork. Addition of organic selenium at a dose of 0.5 ppm alone and with the addition of zeolite showed an immune response raise, higher antioxidant protection and greater increase of selenium in meat production in terms of foods having characteristics of functional food.

  17. Dietary linseed oil supplemented with organic selenium improved the fatty acid nutritional profile, muscular selenium deposition, water retention, and tenderness of fresh pork.

    Science.gov (United States)

    Jiang, Jiang; Tang, Xinyue; Xue, Yan; Lin, Gang; Xiong, Youling L

    2017-09-01

    Cross-bred pigs were fed a control diet (with 0.3ppm sodium selenite and 1.5% soybean oil) or organic selenium diets (0.3ppm Se-Yeast with 1.5% soybean or linseed oil) to investigate nutrient supplement effects on meat quality and oxidative stability. The organic selenium diets increased muscular selenium content up to 54%, and linseed oil increased n-3 fatty acids two-fold while lowering the n-6/n-3 fatty acid ratio from 13.9 to 5.9 over the selenite control diet (Pmeat storage (4°C up to 6days) showed no appreciable difference (P>0.05) between diets, in agreement with the lack of notable difference in endogenous antioxidant enzyme activity between these meat groups. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Arsenic and Selenium

    Science.gov (United States)

    Plant, J. A.; Kinniburgh, D. G.; Smedley, P. L.; Fordyce, F. M.; Klinck, B. A.

    2003-12-01

    Arsenic (As) and selenium (Se) have become increasingly important in environmental geochemistry because of their significance to human health. Their concentrations vary markedly in the environment, partly in relation to geology and partly as a result of human activity. Some of the contamination evident today probably dates back to the first settled civilizations which used metals.Arsenic is in group 15 of the periodic table (Table 1) and is usually described as a metalloid. It has only one stable isotope, 75As. It can exist in the -III, -I, 0, III, and V oxidation states (Table 2).

  19. Effects of dietary selenium supplementation on DNA damage and apoptosis in canine prostate.

    Science.gov (United States)

    Waters, David J; Shen, Shuren; Cooley, Dawn M; Bostwick, David G; Qian, Junqi; Combs, Gerald F; Glickman, Lawrence T; Oteham, Carol; Schlittler, Deborah; Morris, J Steven

    2003-02-05

    The trace mineral selenium inhibits cancer development in a variety of experimental animal models. We used an in vivo canine model to evaluate the effects of dietary selenium supplementation on DNA damage in prostate tissue and on apoptosis in prostate epithelial cells. Sexually intact elderly male beagle dogs were randomly assigned to receive an unsupplemented diet (control group) or diets that were supplemented with selenium (treatment group), either as selenomethionine or as high-selenium yeast at 3 micro g/kg or 6 micro g/kg body weight per day for 7 months. The extent of DNA damage in prostate cells and in peripheral blood lymphocytes, as determined by the alkaline comet assay, was lower among the selenium-supplemented dogs than among the control dogs (prostate Pdogs and 1.7 (interquartile range = 0.2-2.8) for the control dogs ( P =.04, Mann-Whitney U test). These data suggest that dietary selenium supplementation decreases DNA damage and increases epithelial cell apoptosis within the aging canine prostate.

  20. Selenium and thyroid autoimmunity

    Directory of Open Access Journals (Sweden)

    Roberto Negro

    2008-06-01

    Full Text Available Roberto NegroDepartment of Endocrinology, “V. Fazzi” Hospital, Lecce, ItalyAbstract: The trace element selenium (Se occurs in the form of the amino acid selenocysteine in selenoproteins. Selenoproteins exerts multiple physiological effects in human health, many of which are related with regulation of reduction-oxidation processes. In fact, the selenoenzyme families of glutathione peroxidase (GPx and thioredoxin reductase (TRx display the ability to act as antioxidants, protecting cells from oxidative damage. Furthermore, another class of selenoproteins are the iodothyronine deiodinase enzymes (DIO, which catalyze the conversion of thyroxine (T4 in triiodothyronine (T3, then exerting a fine tuned control on thyroid hormones metabolism. Several studies have investigated the potential positive effects of Se supplementation in thyroid diseases, characterized by increased levels of hydrogen peroxide and free radicals, like autoimmune chronic thyroiditis. These studies have supplied evidences indicating that Se supplementation, maximizing the antioxidant enzymes activity, may reduce the thyroid inflammatory status. Then, it may be postulated that Se could play a therapeutical role in thyroid autoimmune diseases. Despite the fact that recent studies seem to be concordant about Se beneficial effects in decreasing thyroid peroxidase antibodies (TPOAb titers and ameliorating the ultrasound echogenicity pattern, several doubts have to be still clarified, before advising Se supplementation in chronic autoimmune thyroiditis.Keywords: selenium, thyroid, autoimmunity

  1. Review on Nano SeleniumProduced by Bacteria

    OpenAIRE

    LI Ji-xiang; Wu, Wen-Liang; GUO Yan-bin

    2014-01-01

    Selenium (Se) is a kind of essential trace element for people and animal, while ionic state of selenium is toxic with high concentrations and will cause the selenium pollution. Nano-selenium is stable, nontoxic with higher biological activity. Application of bacteria reducing selenite or selenate to biological nano-selenium has great potential in selenium pollution control and nano-selenium production. This review summarizes the research progress of the red elemental nano-selenium reduced by ...

  2. Phytoremediation of selenium using transgenic plants.

    Science.gov (United States)

    Pilon-Smits, Elizabeth A H; LeDuc, Danika L

    2009-04-01

    Selenium (Se) is a micronutrient for many organisms but also toxic at higher concentrations. Both selenium deficiency and toxicity are serious problems worldwide. Owing to the similarity of selenium to sulfur, plants readily take up and assimilate selenate via sulfur transporters and enzymes and can even volatilize selenium. Selenium accumulating or volatilizing plants may be used for phytoremediation of selenium pollution and as fortified foods. Several transgenic approaches have been used successfully to further enhance plant selenium accumulation, tolerance, and volatilization: upregulation of genes involved in sulfur/selenium assimilation and volatilization, methylation of selenocysteine, and conversion of selenocysteine to elemental Se. Lab and field trials with different transgenic plants have yielded promising results, showing up to ninefold higher levels of selenium accumulation and up to threefold faster volatilization rates.

  3. Selenium neurotoxicity in humans: bridging laboratory and epidemiologic studies.

    Science.gov (United States)

    Vinceti, Marco; Mandrioli, Jessica; Borella, Paola; Michalke, Bernhard; Tsatsakis, Aristidis; Finkelstein, Yoram

    2014-10-15

    Selenium is a metalloid of considerable interest in the human from both a toxicological and a nutritional perspective, with a very narrow safe range of intake. Acute selenium intoxication is followed by adverse effects on the nervous system with special clinical relevance, while the neurotoxicity of long-term overexposure is less characterized and recognized. We aimed to address this issue from a public health perspective, focusing on both laboratory studies and the few epidemiologic human studies available, with emphasis on their methodological strengths and limitations. The frequently overlooked differences in toxicity and biological activity of selenium compounds are also outlined. In addition to lethargy, dizziness, motor weakness and paresthesias, an excess risk of amyotrophic lateral sclerosis is the effect on the nervous system which has been more consistently associated with chronic low-level selenium overexposure, particularly to its inorganic compounds. Additional research efforts are needed to better elucidate the neurotoxic effects exerted by selenium overexposure. Copyright © 2013 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  4. The Effect of Selenium Supplementation on Glucose Homeostasis and the Expression of Genes Related to Glucose Metabolism.

    Science.gov (United States)

    Jablonska, Ewa; Reszka, Edyta; Gromadzinska, Jolanta; Wieczorek, Edyta; Krol, Magdalena B; Raimondi, Sara; Socha, Katarzyna; Borawska, Maria H; Wasowicz, Wojciech

    2016-12-13

    The aim of the study was to evaluate the effect of selenium supplementation on the expression of genes associated with glucose metabolism in humans, in order to explain the unclear relationship between selenium and the risk of diabetes. For gene expression analysis we used archival samples of cDNA from 76 non-diabetic subjects supplemented with selenium in the previous study. The supplementation period was six weeks and the daily dose of selenium was 200 µg (as selenium yeast). Blood for mRNA isolation was collected at four time points: before supplementation, after two and four weeks of supplementation, and after four weeks of washout. The analysis included 15 genes encoding selected proteins involved in insulin signaling and glucose metabolism. In addition, HbA1c and fasting plasma glucose were measured at three and four time points, respectively. Selenium supplementation was associated with a significantly decreased level of HbA1c but not fasting plasma glucose (FPG) and significant down-regulation of seven genes: INSR, ADIPOR1, LDHA, PDHA, PDHB, MYC, and HIF1AN. These results suggest that selenium may affect glycemic control at different levels of regulation, linked to insulin signaling, glycolysis, and pyruvate metabolism. Further research is needed to investigate mechanisms of such transcriptional regulation and its potential implication in direct metabolic effects.

  5. The Effect of Selenium Supplementation on Glucose Homeostasis and the Expression of Genes Related to Glucose Metabolism

    Directory of Open Access Journals (Sweden)

    Ewa Jablonska

    2016-12-01

    Full Text Available The aim of the study was to evaluate the effect of selenium supplementation on the expression of genes associated with glucose metabolism in humans, in order to explain the unclear relationship between selenium and the risk of diabetes. For gene expression analysis we used archival samples of cDNA from 76 non-diabetic subjects supplemented with selenium in the previous study. The supplementation period was six weeks and the daily dose of selenium was 200 µg (as selenium yeast. Blood for mRNA isolation was collected at four time points: before supplementation, after two and four weeks of supplementation, and after four weeks of washout. The analysis included 15 genes encoding selected proteins involved in insulin signaling and glucose metabolism. In addition, HbA1c and fasting plasma glucose were measured at three and four time points, respectively. Selenium supplementation was associated with a significantly decreased level of HbA1c but not fasting plasma glucose (FPG and significant down-regulation of seven genes: INSR, ADIPOR1, LDHA, PDHA, PDHB, MYC, and HIF1AN. These results suggest that selenium may affect glycemic control at different levels of regulation, linked to insulin signaling, glycolysis, and pyruvate metabolism. Further research is needed to investigate mechanisms of such transcriptional regulation and its potential implication in direct metabolic effects.

  6. Selenium and pseudoexfoliation syndrome.

    Science.gov (United States)

    Yilmaz, Ayça; Ayaz, Lokman; Tamer, Lülüfer

    2011-02-01

    To investigate the levels of selenium (Se), an essential trace element, in aqueous humor, conjunctival specimens, and serum of patients with pseudoexfoliation (PEX) syndrome and control subjects; and to determine the role of Se in the development and pathogenesis of PEX syndrome. A prospective case-control study. Twenty-seven cataract patients with PEX syndrome and 20 age-matched cataract patients without PEX syndrome were enrolled in this institutional study. Patients with ophthalmic conditions other than PEX and conditions that may influence Se levels were excluded. During cataract surgeries, aqueous humor, conjunctival specimens, and serum were collected in both groups. Selenium levels of all samples were measured by using atomic absorption spectrophotometer. The mean Se levels in aqueous humor of patients with PEX syndrome (50.96 ± 23.79 μg/L) were significantly lower than the control group (77.85 ± 19.21 μg/L) (P < .001). The mean Se levels in conjunctival specimens of patients with PEX syndrome (4.04 ± 1.44 μg/mg) were significantly lower than the control group (7.19 ± 2.00 μg/mg) (P < .001), as well. The mean Se levels in serum of patients with PEX syndrome (115.25 ± 25.20 μg/L) were lower than the control group (124.25 ± 14.40 μg/L), but this was not statistically significant (P = .325). Reduced levels of Se in aqueous humor, conjunctival specimens, and serum of patients with PEX may support the role of impairment in antioxidant defense system in the pathogenesis of PEX syndrome. Copyright © 2011 Elsevier Inc. All rights reserved.

  7. Baseline selenium status and effects of selenium and vitamin e supplementation on prostate cancer risk.

    Science.gov (United States)

    Kristal, Alan R; Darke, Amy K; Morris, J Steven; Tangen, Catherine M; Goodman, Phyllis J; Thompson, Ian M; Meyskens, Frank L; Goodman, Gary E; Minasian, Lori M; Parnes, Howard L; Lippman, Scott M; Klein, Eric A

    2014-03-01

    The Selenium and Vitamin E Cancer Prevention Trial found no effect of selenium supplementation on prostate cancer (PCa) risk but a 17% increased risk from vitamin E supplementation. This case-cohort study investigates effects of selenium and vitamin E supplementation conditional upon baseline selenium status. There were 1739 total and 489 high-grade (Gleason 7-10) PCa cases and 3117 men in the randomly selected cohort. Proportional hazards models estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for effects of supplementation within quintiles of baseline toenail selenium. Cox proportional hazards models were used to estimate hazard ratios, and all statistical tests are two-sided. Toenail selenium, in the absence of supplementation, was not associated with PCa risk. Selenium supplementation (combined selenium only and selenium + vitamin E arms) had no effect among men with low selenium status (selenium) but increased the risk of high-grade PCa among men with higher selenium status by 91% (P = .007). Vitamin E supplementation (alone) had no effect among men with high selenium status (≥40th percentile of toenail selenium) but increased the risks of total, low-grade, and high-grade PCa among men with lower selenium status (63%, P = .02; 46%, P = .09; 111%, P = .008, respectively). Selenium supplementation did not benefit men with low selenium status but increased the risk of high-grade PCa among men with high selenium status. Vitamin E increased the risk of PCa among men with low selenium status. Men should avoid selenium or vitamin E supplementation at doses that exceed recommended dietary intakes.

  8. Selenium in Pig Nutrition and Reproduction: Boars and Semen Quality—A Review

    Directory of Open Access Journals (Sweden)

    Peter F. Surai

    2015-05-01

    Full Text Available Selenium plays an important role in boar nutrition via participating in selenoprotein synthesis. It seems likely that selenoproteins are central for antioxidant system regulation in the body. Se-dependent enzyme glutathione peroxidase (GSH-Px is the most studied selenoprotein in swine production. However, roles of other selenoproteins in boar semen production and maintenance of semen quality also need to be studied. Boar semen is characterised by a high proportion of easily oxidized long chain polyunsaturated fatty acids and requires an effective antioxidant defense. The requirement of swine for selenium varies depending on many environmental and other conditions and, in general, is considered to be 0.15 to 0.30 mg/kg feed. It seems likely that reproducing sows and boars are especially sensitive to Se deficiency, and meeting their requirements is an important challenge for pig nutritionists. In fact, in many countries there are legal limits as to how much Se may be included into the diet and this restricts flexibility in terms of addressing the Se needs of the developing and reproducing swine. The analysis of data of various boar trials with different Se sources indicates that in some cases when background Se levels were low, there were advantages of Se dietary supplementation. It is necessary to take into account that only an optimal Se status of animals is associated with the best antioxidant protection and could have positive effects on boar semen production and its quality. However, in many cases, background Se levels were not determined and therefore, it is difficult to judge if the basic diets were deficient in Se. It can also be suggested that, because of higher efficacy of assimilation from the diet, and possibilities of building Se reserves in the body, organic selenium in the form of selenomethionine (SeMet provided by a range of products, including Se-Yeast and SeMet preparations is an important source of Se to better meet the needs

  9. Geiten krijgen meestal te veel selenium

    NARCIS (Netherlands)

    Smolders, E.A.A.; Govaerts, W.; Eekeren, van N.J.M.

    2010-01-01

    Geiten gaan efficiënt om met selenium. Mede daardoor zijn de bloedwaardes voor selenium bij geiten vaak hoog, en soms te hoog, zo bleek na bloedonderzoek op dertien biologische geitenbedrijven binnen het project Biogeit. Te veel selenium is schadelijk voor geiten.

  10. Opportunistic Pathogenic Yeasts

    Science.gov (United States)

    Banerjee, Uma

    Advances in medical research, made during the last few decades, have improved the prophylactic, diagnostic and therapeutic capabilities for variety of infections/diseases. However, many of the prophylactic and therapeutic procedures have been seen in many instances to exact a price of host-vulnerability to an expanding group of opportunistic pathogens and yeasts are one of the important members in it. Fortunately amongst the vast majority of yeasts present in nature only few are considered to have the capability to cause infections when certain opportunities predisposes and these are termed as ‘opportunistic pathogenic yeasts.’ However, the term ‘pathogenic’ is quite tricky, as it depends of various factors of the host, the ‘bug’ and the environment to manifest the clinical infection. The borderline is expanding. In the present century with unprecedented increase in number of immune-compromised host in various disciplines of health care settings, where any yeast, which has the capability to grow at 37 ° C (normal body temperature of human), can be pathogenic and cause infection in particular situation

  11. Selenium accumulation by plants.

    Science.gov (United States)

    White, Philip J

    2016-02-01

    Selenium (Se) is an essential mineral element for animals and humans, which they acquire largely from plants. The Se concentration in edible plants is determined by the Se phytoavailability in soils. Selenium is not an essential element for plants, but excessive Se can be toxic. Thus, soil Se phytoavailability determines the ecology of plants. Most plants cannot grow on seleniferous soils. Most plants that grow on seleniferous soils accumulate plant species have evolved tolerance to Se, and commonly accumulate tissue Se concentrations >100 mg Se kg(-1) dry matter. These plants are considered to be Se accumulators. Some species can even accumulate Se concentrations of 1000-15 000 mg Se kg(-1 )dry matter and are called Se hyperaccumulators. This article provides an overview of Se uptake, translocation and metabolism in plants and highlights the possible genetic basis of differences in these between and within plant species. The review focuses initially on adaptations allowing plants to tolerate large Se concentrations in their tissues and the evolutionary origin of species that hyperaccumulate Se. It then describes the variation in tissue Se concentrations between and within angiosperm species and identifies genes encoding enzymes limiting the rates of incorporation of Se into organic compounds and chromosomal loci that might enable the development of crops with greater Se concentrations in their edible portions. Finally, it discusses transgenic approaches enabling plants to tolerate greater Se concentrations in the rhizosphere and in their tissues. The trait of Se hyperaccumulation has evolved several times in separate angiosperm clades. The ability to tolerate large tissue Se concentrations is primarily related to the ability to divert Se away from the accumulation of selenocysteine and selenomethionine, which might be incorporated into non-functional proteins, through the synthesis of less toxic Se metabilites. There is potential to breed or select crops

  12. Middle-Term Dietary Supplementation with Red Yeast Rice Plus Coenzyme Q10 Improves Lipid Pattern, Endothelial Reactivity and Arterial Stiffness in Moderately Hypercholesterolemic Subjects.

    Science.gov (United States)

    Cicero, Arrigo F G; Morbini, Martino; Rosticci, Martina; D''Addato, Sergio; Grandi, Elisa; Borghi, Claudio

    2016-01-01

    The aim of our study was to investigate whether treatment with red yeast rice added with Coenzyme Q10 is associated with changes in endothelial function and arterial stiffness. This double blind, placebo-controlled, randomized clinical trial was carried out on 40 non-smoker moderately hypercholesterolemic subjects (ClinicalTrial.gov ID NCT02492464). After 4 weeks of diet and physical activity, patients were allocated to treatment with placebo or with an active product containing 10 mg monacolins and 30 mg Coenzyme Q10, to be assumed for 6 months. Endothelial reactivity and arterial stiffness have been measured through the validated Vicorder® device. During monacolin treatment, patients experienced a more favorable percentage change in low density lipoprotein (LDL)-cholesterol (after monacolin treatment: -26.3%; after placebo treatment: +3.4%, p < 0.05). Endothelial reactivity (pulse volume displacement after monacolin treatment: +6.0%; after placebo treatment: -0.3%, p < 0.05), and arterial stiffness (pulse wave velocity (PWV) after monacolin treatment: -4.7%; after placebo: +1.1%, p < 0.05) also significantly improved only after monacolin treatment. The long-term assumption of the tested dietary supplement is associated with an improvement in LDL-cholesterolemia, endothelial reactivity and PWV in moderately hypercholesterolemic subjects. © 2016 S. Karger AG, Basel.

  13. Selenium and inflammatory bowel disease.

    Science.gov (United States)

    Kudva, Avinash K; Shay, Ashley E; Prabhu, K Sandeep

    2015-07-15

    Dietary intake of the micronutrient selenium is essential for normal immune functions. Selenium is cotranslationally incorporated as the 21st amino acid, selenocysteine, into selenoproteins that function to modulate pathways involved in inflammation. Epidemiological studies have suggested an inverse association between selenium levels and inflammatory bowel disease (IBD), which includes Crohn's disease and ulcerative colitis that can potentially progress to colon cancer. However, the underlying mechanisms are not well understood. Here we summarize the current literature on the pathophysiology of IBD, which is multifactorial in origin with unknown etiology. We have focused on a few selenoproteins that mediate gastrointestinal inflammation and activate the host immune response, wherein macrophages play a pivotal role. Changes in cellular oxidative state coupled with altered expression of selenoproteins in macrophages drive the switch from a proinflammatory phenotype to an anti-inflammatory phenotype to efficiently resolve inflammation in the gut and restore epithelial barrier integrity. Such a phenotypic plasticity is accompanied by changes in cytokines, chemokines, and bioactive metabolites, including eicosanoids that not only mitigate inflammation but also partake in restoring gut homeostasis through diverse pathways involving differential regulation of transcription factors such as nuclear factor-κB and peroxisome proliferator-activated receptor-γ. The role of the intestinal microbiome in modulating inflammation and aiding in selenium-dependent resolution of gut injury is highlighted to provide novel insights into the beneficial effects of selenium in IBD. Copyright © 2015 the American Physiological Society.

  14. Biomarkers of Selenium Status

    Science.gov (United States)

    Combs, Gerald F.

    2015-01-01

    The essential trace element, selenium (Se), has multiple biological activities, which depend on the level of Se intake. Relatively low Se intakes determine the expression of selenoenzymes in which it serves as an essential constituent. Higher intakes have been shown to have anti-tumorigenic potential; and very high Se intakes can produce adverse effects. This hierarchy of biological activities calls for biomarkers informative at different levels of Se exposure. Some Se-biomarkers, such as the selenoproteins and particularly GPX3 and SEPP1, provide information about function directly and are of value in identifying nutritional Se deficiency and tracking responses of deficient individuals to Se-treatment. They are useful under conditions of Se intake within the range of regulated selenoprotein expression, e.g., for humans health considerations. This would include determining whether supranutritional intakes of Se may be required for maximal selenoprotein expression in immune surveillance cells. It would also include developing methods to determine low molecular weight Se-metabolites, i.e., selenoamino acids and methylated Se-metabolites, which to date have not been detectable in biological specimens. Recent analytical advances using tandem liquid chromatography-mass spectrometry suggest prospects for detecting these metabolites. PMID:25835046

  15. Plasma Selenium Biomarkers in Low Income Black and White Americans from the Southeastern United States

    Science.gov (United States)

    Hargreaves, Margaret K.; Liu, Jianguo; Buchowski, Maciej S.; Patel, Kushal A.; Larson, Celia O.; Schlundt, David G.; Kenerson, Donna M.; Hill, Kristina E.; Burk, Raymond F.; Blot, William J.

    2014-01-01

    Biomarkers of selenium are necessary for assessing selenium status in humans, since soil variation hinders estimation of selenium intake from foods. In this study, we measured the concentration of plasma selenium, selenoprotein P (SEPP1), and glutathione peroxidase (GPX3) activity and their interindividual differences in 383 low-income blacks and whites selected from a stratified random sample of adults aged 40–79 years, who were participating in a long-term cohort study in the southeastern United States (US). We assessed the utility of these biomarkers to determine differences in selenium status and their association with demographic, socio-economic, dietary, and other indicators. Dietary selenium intake was assessed using a validated food frequency questionnaire designed for the cohort, matched with region-specific food selenium content, and compared with the US Recommended Dietary Allowances (RDA) set at 55 µg/day. We found that SEPP1, a sensitive biomarker of selenium nutritional status, was significantly lower among blacks than whites (mean 4.4±1.1 vs. 4.7±1.0 mg/L, p = 0.006), with blacks less than half as likely to have highest vs. lowest quartile SEPP1 concentration (Odds Ratio (OR) 0.4, 95% Confidence Interval (CI) 0.2–0.8). The trend in a similar direction was observed for plasma selenium among blacks and whites, (mean 115±15.1 vs. 118±17.7 µg/L, p = 0.08), while GPX3 activity did not differ between blacks and whites (136±33.3 vs. 132±33.5 U/L, p = 0.320). Levels of the three biomarkers were not correlated with estimated dietary selenium intake, except for SEPP1 among 10% of participants with the lowest selenium intake (≤57 µg/day). The findings suggest that SEPP1 may be an effective biomarker of selenium status and disease risk in adults and that low selenium status may disproportionately affect black and white cohort participants. PMID:24465457

  16. Plasma selenium biomarkers in low income black and white americans from the southeastern United States.

    Directory of Open Access Journals (Sweden)

    Margaret K Hargreaves

    Full Text Available Biomarkers of selenium are necessary for assessing selenium status in humans, since soil variation hinders estimation of selenium intake from foods. In this study, we measured the concentration of plasma selenium, selenoprotein P (SEPP1, and glutathione peroxidase (GPX3 activity and their interindividual differences in 383 low-income blacks and whites selected from a stratified random sample of adults aged 40-79 years, who were participating in a long-term cohort study in the southeastern United States (US. We assessed the utility of these biomarkers to determine differences in selenium status and their association with demographic, socio-economic, dietary, and other indicators. Dietary selenium intake was assessed using a validated food frequency questionnaire designed for the cohort, matched with region-specific food selenium content, and compared with the US Recommended Dietary Allowances (RDA set at 55 µg/day. We found that SEPP1, a sensitive biomarker of selenium nutritional status, was significantly lower among blacks than whites (mean 4.4 ± 1.1 vs. 4.7 ± 1.0 mg/L, p = 0.006, with blacks less than half as likely to have highest vs. lowest quartile SEPP1 concentration (Odds Ratio (OR 0.4, 95% Confidence Interval (CI 0.2-0.8. The trend in a similar direction was observed for plasma selenium among blacks and whites, (mean 115 ± 15.1 vs. 118 ± 17.7 µg/L, p = 0.08, while GPX3 activity did not differ between blacks and whites (136 ± 33.3 vs. 132 ± 33.5 U/L, p = 0.320. Levels of the three biomarkers were not correlated with estimated dietary selenium intake, except for SEPP1 among 10% of participants with the lowest selenium intake (≤ 57 µg/day. The findings suggest that SEPP1 may be an effective biomarker of selenium status and disease risk in adults and that low selenium status may disproportionately affect black and white cohort participants.

  17. Selenium supplementation for the primary prevention of cardiovascular disease.

    Science.gov (United States)

    Rees, Karen; Hartley, Louise; Day, Camilla; Flowers, Nadine; Clarke, Aileen; Stranges, Saverio

    2013-01-31

    Selenium is a key component of a number of selenoproteins which protect against oxidative stress and have the potential to prevent chronic diseases including cardiovascular disease (CVD). However, observational studies have shown inconsistent associations between selenium intake and CVD risk; in addition, there is concern around a possible increased risk of type 2 diabetes with high selenium exposure. To determine the effectiveness of selenium only supplementation for the primary prevention of CVD and examine the potential adverse effect of type 2 diabetes. The following electronic databases were searched: the Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 10 of 12, October 2012) on The Cochrane Library; MEDLINE (Ovid) (1946 to week 2 October 2012); EMBASE Classic + EMBASE (Ovid) (1947 to 2012 Week 42); CINAHL (EBSCO) (to 24 October 2012); ISI Web of Science (1970 to 24 October 2012); PsycINFO (Ovid) (1806 to week 3 October 2012); Database of Abstracts of Reviews of Effects (DARE), Health Technology Assessment Database and Health Economics Evaluations Database (Issue 4 of 4, October 2012) on The Cochrane Library. Trial registers and reference lists of reviews and articles were searched and experts in the field were approached. No language restrictions were applied. Randomised controlled trials on the effects of selenium only supplementation on major CVD end-points, mortality, changes in CVD risk factors, and type 2 diabetes were included both in adults of all ages from the general population and in those at high risk of CVD. Trials were only considered where the comparison group was placebo or no intervention. Only studies with at least three months follow-up were included in the meta-analyses, shorter term studies were dealt with descriptively. Two review authors independently assessed trial quality and extracted data. Study authors were contacted for additional information. Twelve trials (seven with duration of at least three months) met the

  18. Selenium Content in Seafood in Japan

    Directory of Open Access Journals (Sweden)

    Haruka Iida

    2013-01-01

    Full Text Available Selenium is an essential micronutrient for humans, and seafood is one of the major selenium sources, as well as red meat, grains, eggs, chicken, liver and garlic. A substantial proportion of the total amount of selenium is present as selenium containing imidazole compound, selenoneine, in the muscles of ocean fish. In order to characterize the selenium content in seafood, the total selenium levels were measured in the edible portions of commercially important fish and shellfish species. Among the tested edible portions, alfonsino muscle had the highest selenium levels (concentration of 1.27 mg/kg tissue. High levels of selenium (1.20–1.07 mg/kg were also found in the salted ovary products of mullet and Pacific herring. In other fish muscles, the selenium levels ranged between 0.12 and 0.77 mg/kg tissue. The selenium levels were closely correlated with the mercury levels in the white and red muscles in alfonsino. The selenium content in spleen, blood, hepatopancreas, heart, red muscle, white muscle, brain, ovary and testis ranged between 1.10 and 24.8 mg/kg tissue in alfonsino.

  19. Effect of Selenium from Selenium-Enriched Kale Sprout Versus Other Selenium Sources on Productivity and Selenium Concentrations in Egg and Tissue of Laying Hens.

    Science.gov (United States)

    Chantiratikul, Anut; Chinrasri, Orawan; Chantiratikul, Piyanete

    2017-06-07

    A 6-week trial was conducted to compare the effect of selenium (Se) from hydroponically produced Se-enriched kale sprout (HPSeKS), sodium selenite (SS), and Se-enriched yeast (SeY) in laying hens. A total of 144 40-week-old hens were randomly divided into four groups, according to a completely randomized design. Each group consisted of four replicates with nine hens per replicate. The dietary treatments were T1 (basal diet) and T2, T3, and T4 (basal diets supplemented with 0.30 mg Se/kg from SS, SeY, and HPSeKS, respectively). Results showed that Se supplement did not affect (p > 0.05) productivity and egg quality. Hens fed Se from HPSeKS and SeY exhibited higher (p  0.05) to that of hens fed Se from SeY, but higher (p  0.05). The results of this trial demonstrated that Se from HPSeKS and SeY was more efficient than Se from SS on Se bioavailability and whole egg Se concentration in laying hens.

  20. Does selenium supplementation affect thyroid function?

    DEFF Research Database (Denmark)

    Winther, Kristian Hillert; Bonnema, Steen Joop; Cold, Frederik

    2015-01-01

    OBJECTIVE: Selenium is present in the active site of proteins important for thyroid hormone synthesis and metabolism. The objective of this study is to investigate the effect of selenium supplementation in different doses on thyroid function, under conditions of suboptimal dietary selenium intake......=0.015), respectively, per 100 μg/day increase, with insignificant differences between 6 months and 5 years. No significant effects were found for FT3 and FT3:FT4 ratio. CONCLUSIONS: In euthyroid subjects, selenium supplementation minutely and dose-dependently affects thyroid function, when compared...... with placebo, by decreasing serum TSH and FT4 concentrations. Based on these findings, selenium supplementation is not warranted under conditions of marginal selenium deficiency. However, a role for selenium supplementation in the treatment of autoimmune thyroid diseases is still unresolved....

  1. Biomarkers of Selenium Status

    Directory of Open Access Journals (Sweden)

    Gerald F. Combs, Jr.

    2015-03-01

    Full Text Available The essential trace element, selenium (Se, has multiple biological activities, which depend on the level of Se intake. Relatively low Se intakes determine the expression of selenoenzymes in which it serves as an essential constituent. Higher intakes have been shown to have anti-tumorigenic potential; and very high Se intakes can produce adverse effects. This hierarchy of biological activities calls for biomarkers informative at different levels of Se exposure. Some Se-biomarkers, such as the selenoproteins and particularly GPX3 and SEPP1, provide information about function directly and are of value in identifying nutritional Se deficiency and tracking responses of deficient individuals to Se-treatment. They are useful under conditions of Se intake within the range of regulated selenoprotein expression, e.g., for humans <55 μg/day and for animals <20 μg/kg diet. Other Se-biomarkers provide information indirectly through inferences based on Se levels of foods, tissues, urine or feces. They can indicate the likelihood of deficiency or adverse effects, but they do not provide direct evidence of either condition. Their value is in providing information about Se status over a wide range of Se intake, particularly from food forms. There is need for additional Se biomarkers particularly for assessing Se status in non-deficient individuals for whom the prospects of cancer risk reduction and adverse effects risk are the primary health considerations. This would include determining whether supranutritional intakes of Se may be required for maximal selenoprotein expression in immune surveillance cells. It would also include developing methods to determine low molecular weight Se-metabolites, i.e., selenoamino acids and methylated Se-metabolites, which to date have not been detectable in biological specimens. Recent analytical advances using tandem liquid chromatography-mass spectrometry suggest prospects for detecting these metabolites.

  2. Nutrigenetics, nutrigenomics and selenium

    Directory of Open Access Journals (Sweden)

    Lynnette Robiin Ferguson

    2011-04-01

    Full Text Available Selenium (Se is an important micronutrient that, as a component of selenoproteins, influences oxidative and inflammatory processes. Its’ levels vary considerably, with different ethnic and geographic population groups showing varied conditions, ranging from frank Se deficiencies to toxic effects. An optimum Se level is essential for the maintenance of homeostasis, and this optimum may vary according to life stage, general state of health and genotype. Nutrigenetic studies of different Se levels, in the presence of genetic variants in selenoproteins, suggest that an effective dietary Se intake for one individual may be very different from that for others. However, we are just starting to learn the significance of various genes in selenoprotein pathways, functional variants in these, and how to combine such data from genes into pathways, alongside dietary intake or serum levels of Se. Advances in systems biology, genetics and genomics technologies, including genetic/genomic, epigenetic/epigenomic, transcriptomic, proteomic and metabolomic information, start to make it feasible to assess a comprehensive spectrum of the biological activity of Se. Such nutrigenomic approaches may prove very sensitive biomarkers of optimal Se status at the individual or population level. The premature cessation of a major human Se intervention trial has led to considerable controversy as to the value of Se supplementation at the population level. New websites provide convenient links to current information on methodologies available for nutrigenetics and nutrigenomics. These new technologies will increasingly become an essential tool in optimising the level of Se and other micronutrients for optimal health, in individuals and in population groups. However, definitive proof of such effects will require very large collaborative studies, international agreement on study design and innovative approaches to data analysis.

  3. Interplay between Selenium Levels and Replicative Senescence in WI-38 Human Fibroblasts: A Proteomic Approach

    Directory of Open Access Journals (Sweden)

    Ghania Hammad

    2018-01-01

    Full Text Available Selenoproteins are essential components of antioxidant defense, redox homeostasis, and cell signaling in mammals, where selenium is found in the form of a rare amino acid, selenocysteine. Selenium, which is often limited both in food intake and cell culture media, is a strong regulator of selenoprotein expression and selenoenzyme activity. Aging is a slow, complex, and multifactorial process, resulting in a gradual and irreversible decline of various functions of the body. Several cellular aspects of organismal aging are recapitulated in the replicative senescence of cultured human diploid fibroblasts, such as embryonic lung fibroblast WI-38 cells. We previously reported that the long-term growth of young WI-38 cells with high (supplemented, moderate (control, or low (depleted concentrations of selenium in the culture medium impacts their replicative lifespan, due to rapid changes in replicative senescence-associated markers and signaling pathways. In order to gain insight into the molecular link between selenium levels and replicative senescence, in the present work, we have applied a quantitative proteomic approach based on 2-Dimensional Differential in-Gel Electrophoresis (2D-DIGE to the study of young and presenescent cells grown in selenium-supplemented, control, or depleted media. Applying a restrictive cut-off (spot intensity ±50% and a p value < 0.05 to the 2D-DIGE analyses revealed 81 differentially expressed protein spots, from which 123 proteins of interest were identified by mass spectrometry. We compared the changes in protein abundance for three different conditions: (i spots varying between young and presenescent cells, (ii spots varying in response to selenium concentration in young cells, and (iii spots varying in response to selenium concentration in presenescent cells. Interestingly, a 72% overlap between the impact of senescence and selenium was observed in our proteomic results, demonstrating a strong interplay between

  4. Toenail selenium status and risk of subtypes of head-neck cancer: The Netherlands Cohort Study.

    Science.gov (United States)

    Maasland, Denise H E; Schouten, Leo J; Kremer, Bernd; van den Brandt, Piet A

    2016-06-01

    There is limited prospective data on the relationship between selenium status and the risk of head-neck cancer (HNC) and HNC subtypes (i.e., oral cavity cancer [OCC], oro-/hypopharyngeal cancer [OHPC] and laryngeal cancer [LC]). Therefore, we investigated the association between toenail selenium, reflecting long-term selenium exposure, and HNC risk within the Netherlands Cohort Study. At baseline, 120,852 participants completed a self-administered questionnaire about diet and other cancer risk factors and were asked to provide toenail clippings. After 20.3 years of follow-up, 294 cases of HNC (95 OCC, 62 OHPC, two oral cavity/pharynx unspecified or overlapping and 135 LC) and 2,164 subcohort members were available for case-cohort analysis using Cox proportional hazards models. Toenail selenium status was statistically significantly associated with a decreased risk of HNC overall (multivariate RR for quartile four versus one: 0.55, 95% confidence interval [CI] 0.37-0.82, P trend = 0.001). The association between toenail selenium and risk of HNC overall was stronger among men than women, but no statistically significant interaction with sex was found. Toenail selenium level was also associated with a decreased risk of all HNC subtypes, with statistically significant associations in OHPC and LC. No statistically significant interaction was found between toenail selenium level and cigarette smoking or alcohol consumption for HNC overall. In this large cohort study, we found an inverse association between toenail selenium level and HNC risk. Among HNC subtypes, this association was strongest for OHPC and LC. Furthermore, the association of toenail selenium status with HNC risk was stronger among men than women. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. The favourable effects of long-term selenium supplementation on regression of cervical tissues and metabolic profiles of patients with cervical intraepithelial neoplasia: a randomised, double-blind, placebo-controlled trial.

    Science.gov (United States)

    Karamali, Maryam; Nourgostar, Sepideh; Zamani, Ashraf; Vahedpoor, Zahra; Asemi, Zatollah

    2015-12-28

    This study was conducted to assess the effects of long-term Se administration on the regression and metabolic status of patients with cervical intraepithelial neoplasia grade 1 (CIN1). This randomised, double-blind, placebo-controlled trial was carried out among fifty-eight women diagnosed with CIN1. To diagnose CIN1, we used specific diagnostic procedures of biopsy, pathological diagnosis and colposcopy. Patients were randomly assigned to two groups to receive 200 μg Se supplements as Se yeast (n 28) or placebo (n 28) daily for 6 months. After 6 months of taking Se supplements, a greater percentage of women in the Se group had regressed CIN1 (88·0 v. 56·0 %; P=0·01) compared with those in the placebo group. Long-term Se supplementation, compared with the placebo, resulted in significant decreases in fasting plasma glucose levels (-0·37 (sd 0·32) v. +0·07 (sd 0·63) mmol/l; P=0·002), serum insulin levels (-28·8 (sd 31·2) v. +13·2 (sd 40·2) pmol/l; Pplacebo group, there were significant rises in plasma total antioxidant capacity (+186·1 (sd 274·6) v. +42·8 (sd 180·4) mmol/l; P=0·02) and GSH levels (+65·0 (sd 359·8) v. -294·2 (sd 581·8) μmol/l; P=0·007) and a significant decrease in malondialdehyde levels (-1·5 (sd 2·1) v. +0·1 (sd 1·4) μmol/l; P=0·001) among those who took Se supplements. Overall, taking Se supplements among patients with CIN1 led to its regression and had beneficial effects on their metabolic profiles.

  6. Effect of Selenium, Molybdenum and Zinc on Seedling Growth and Frequency of Grain Weevil (Sitophilus granarius in Triticale Grain

    Directory of Open Access Journals (Sweden)

    Rudolf Kastori

    2009-01-01

    Full Text Available The effects of different doses (0, 90, 270, 810 kg/ha of selenium, molybdenum and zinc microelements on their translocation and accumulation in grains, seedling growth and grain infestation were examined under field conditions on a calcareous chernozem soil.Thirteen years after the application of selenium, molybdenum and zinc, significant translocation and accumulation of these elements in the grain were established, indicating a long-term effect of these microelements on triticale plants. The highest degree of accumulation in grains and seedling shoots was found for selenium, then molybdenum, while the detected amounts of zinc were significantly lower. The degree of accumulation of all threemicroelements in the grain and seedling shoot increased as doses increased. Translocation index from shoot to grain at the grain-filling phase was the highest when zinc was used, then selenium, and the lowest when molybdenum was applied. The highest translocationindex from the grain during germination into seedling shoots was obtained with zinc, then molybdenum and selenium. Translocation indexes of the investigated elements significantly decreased as the doses of elements increased. Dry weight of seedling shoots decreasedas molybdenum and zinc in grain increased. High selenium concentration moderately stimulated seedling development, pointing out a high tolerance of triticale to higher concentration of this microelement at initial development stages. Infestatation with grain weevil was provoked by high concentrations of these microelements in the grain. High concentrations of zinc and selenium, in particular, significantly decreased the percentage of damaged grains, while molybdenum moderately increased their numbers. The effect of zincand molybdenum may be attributed to their chemical effect, while selenium effect may also be referred to a negative effect of the volatile selenium compound. The effect of selenium, molybdenum and zinc contamination of grains

  7. Selenium, selenoproteins and neurodegenerative diseases.

    Science.gov (United States)

    Cardoso, Bárbara Rita; Roberts, Blaine R; Bush, Ashley I; Hare, Dominic J

    2015-08-01

    It is unsurprising that our understanding of the role of selenium in neurological function is somewhat immature, considering its relatively recent discovery as an essential element to human health. Selenocysteine, the 21st amino acid, is the defining feature of the 25 selenoprotein-encoding genes so far discovered within the human genome. The low abundance of these proteins in the brain belies the integral role they play in normal neurological function, from well-characterised antioxidant activity in the periphery to poorly understood mechanisms that modulate mitochondrial function and response to brain pathology. Selenium has been identified as playing a role in several neurodegenerative disorders, including Alzheimer's and Parkinson's disease, though its function as a 'cause or effect' of disease process remains unclear. This review discusses selenium metabolism in detail, specifically with regard to the role it plays within the central nervous system, and examines the most current literature investigating how selenium may be involved in chronic diseases of the central nervous system.

  8. Metabolic interrelationships between arsenic and selenium.

    Science.gov (United States)

    Levander, O A

    1977-08-01

    In 1938, Moxon discovered that arsenic protected against selenium toxicity. Since that time it has been shown that this protective effect of arsenic against selenium poisoning can be demonstrated in many different animal species under a wide variety of conditions. Antagonistic effects between arsenic and selenium have also been noted in teratologic experiments. Early metabolic studies showed that arsenic inhibited the expiration of volatile selenium compounds by rats injected with acutely toxic doses of both elements. This was puzzling since pulmonary excretion had long been regarded as a means by which animals could rid themselves of excess selenium. However, later work demonstrated that arsenic increased the biliary excretion of selenium. Not only did arsenic stimulate the excretion of selenium in the bile, but selenium also stimulated the excretion of arsenic in the bile. This increased biliary excretion of selenium caused by arsenic provides a reasonable rationale for the ability of arsenic to counteract the toxicity of selenium, although the chemical mechanism by which arsenic does this is not certain. The most satisfactory explanation is that these two elements react in the liver to form a detoxication conjugate which is then excreted into the bile. This is consistent with the fact that both arsenic and selenium each increase the biliary excretion of the other. Several other metabolic interactions between arsenic and selenium have been demonstrated in vitro, but their physiological significance is not clear. Although arsenic decreased selenium toxicity under most conditions, there is a pronounced synergistic toxicity between arsenic and two methylated selenium metabolites, trimethylselenonium ion or dimethyl selenide. The ecological consequences of these synergisms are largely unexplored, although it is likely that selenium methylation occurs in the environment. All attempts to promote or prevent selenium deficiency diseases in animals by feeding arsenic have

  9. Serum selenium concentration in Mashhad prisoners, Iran.

    Science.gov (United States)

    Ehteshamfar, Seyed-Morteza; Shapouri-Moghaddam, Abbas; Safarian, Mohammad; Nematy, Mohsen; Bahrami-Taghanaki, Hamidreza; Azizi, Hoda

    2012-08-01

    To determine the serum selenium concentration among prisoners in the central jail of Mashhad, Northeast of Iran. In a cross-section study, a sample of 435 prisoners (387 men [34.5±10 years] and 48 women [36.4±11 years]) recruited during May 2008 to June 2008 from Mashhad Central Prison, Mashhad, Iran, using multistage sampling method, proportionate to gender, age groups and kind of crime. Serum level of selenium was assessed using atomic absorption spectrophotometer. The mean of serum selenium concentration was 121±20 ug/l. Prevalence of selenium deficiency was 9.7% in selected sample. The selenium deficiency was more prevalent in women than men (25.5% versus 7.8%, p=0.00). Age distribution of serum selenium level had a different pattern among men and women. While in men serum selenium level on average was least in those aged 50 and over, in women, serum selenium did not change with age. Body mass index (BMI) and weight change had no relations. Results of this study suggest that selenium status of the prisoners in Mashhad central prison is of concern. Women may be at higher risk for selenium deficiency. These results have implications for officials in charge with prisoners and health policy makers.

  10. Genome-wide association study of serum selenium concentrations

    DEFF Research Database (Denmark)

    Gong, Jian; Hsu, Li; Harrison, Tabitha

    2013-01-01

    Selenium is an essential trace element and circulating selenium concentrations have been associated with a wide range of diseases. Candidate gene studies suggest that circulating selenium concentrations may be impacted by genetic variation; however, no study has comprehensively investigated this ...

  11. Shedding Light on Selenium Biomineralization: Proteins Associated with Bionanominerals

    NARCIS (Netherlands)

    Lenz, M.; Kolvenbach, B.; Gygax, B.; Moes, S.; Corvini, P.F.X.

    2011-01-01

    Selenium reducing microorganisms produce elemental selenium nanoparticles with particular physico-chemical properties being due to an associated organic fraction. This study identified high affinity proteins being associated with such bionanominerals and with non-biogenic elemental selenium.

  12. Biomarkers of selenium status in dogs.

    Science.gov (United States)

    van Zelst, Mariëlle; Hesta, Myriam; Gray, Kerry; Staunton, Ruth; Du Laing, Gijs; Janssens, Geert P J

    2016-01-19

    Inadequate dietary selenium (Se) intake in humans and animals can lead to long term health problems, such as cancer. In view of the owner's desire for healthy longevity of companion animals, the impact of dietary Se provision on long term health effects warrants investigation. Little is currently known regards biomarkers, and rate of change of such biomarkers in relation to dietary selenium intake in dogs. In this study, selected biomarkers were assessed for their suitability to detect changes in dietary Se in adult dogs within eight weeks. Twenty-four dogs were fed a semi-purified diet with an adequate amount of Se (46.1 μg/MJ) over an 8 week period. They were then divided into two groups. The first group remained on the adequate Se diet, the second were offered a semi-purified diet with a low Se concentration (6.5 μg/MJ; 31% of the FEDIAF minimum) for 8 weeks. Weekly urine and blood was collected and hair growth measurements were performed. The urinary Se to creatinine ratio and serum Se concentration were significantly lower in dogs consuming the low Se diet from week 1 onwards, by 84% (adequate 25.3, low 4.1) and 7% (adequate 257 μg/L, low 238 μg/L) respectively. Serum and whole blood glutathione peroxidase were also significantly lower in dogs consuming the low Se diet from weeks 6 and 8 respectively. None of the other biomarkers (mRNA expression and serum copper, creatine kinase, triiodothyronine:thyroxine ratio and hair growth) responded significantly to the low Se diet over the 8 week period. This study demonstrated that urinary Se to creatinine ratio, serum Se and serum and whole blood glutathione peroxidase can be used as biomarkers of selenium status in dogs. Urinary Se to creatinine ratio and serum Se concentrations responded faster to decreased dietary Se than the other parameters. This makes these biomarkers candidates for early screening of long term effects of dietary Se provision on canine health.

  13. Chemical form of selenium in naturally selenium-rich lentils (Lens culinaris L.) from Saskatchewan.

    Science.gov (United States)

    Thavarajah, Dil; Vandenberg, Albert; George, Graham N; Pickering, Ingrid J

    2007-09-05

    Lentils (Lens culinaris L.) are a source of many essential dietary components and trace elements for human health. In this study we show that lentils grown in the Canadian prairies are additionally enriched in selenium, an essential micronutrient needed for general well-being, including a healthy immune system and protection against cancer. Selenium K near-edge X-ray absorption spectroscopy (XAS) has been used to examine the selenium biochemistry of two lentil cultivars grown in various locations in Saskatchewan, Canada. We observe significant variations in total selenium concentration with geographic location and cultivar; however, almost all the selenium (86-95%) in these field-grown lentils is present as organic selenium modeled as selenomethionine with a small component (5-14%) as selenate. As the toxicities of certain forms of arsenic and selenium are antagonistic, selenium-rich lentils may have a pivotal role to play in alleviating the chronic arsenic poisoning in Bangladesh.

  14. Chemical Form of Selenium in Naturally Selenium-Rich Lentils (Lens Culinaris L.) From Saskatchewan

    Energy Technology Data Exchange (ETDEWEB)

    Thavarajah, D.; Vandenberg, A.; George, G.N.; Pickering, I.J.

    2009-06-04

    Lentils (Lens culinaris L.) are a source of many essential dietary components and trace elements for human health. In this study we show that lentils grown in the Canadian prairies are additionally enriched in selenium, an essential micronutrient needed for general well-being, including a healthy immune system and protection against cancer. Selenium K near-edge X-ray absorption spectroscopy (XAS) has been used to examine the selenium biochemistry of two lentil cultivars grown in various locations in Saskatchewan, Canada. We observe significant variations in total selenium concentration with geographic location and cultivar; however, almost all the selenium (86--95%) in these field-grown lentils is present as organic selenium modeled as selenomethionine with a small component (5--14%) as selenate. As the toxicities of certain forms of arsenic and selenium are antagonistic, selenium-rich lentils may have a pivotal role to play in alleviating the chronic arsenic poisoning in Bangladesh.

  15. Blood selenium levels and contribution of food groups to selenium intake in adolescent girls in Iceland

    National Research Council Canada - National Science Library

    Gudmundsdottir, Edda Y; Gunnarsdottir, Ingibjorg; Thorlacius, Arngrimur; Reykdal, Olafur; Gunnlaugsdottir, Helga; Thorsdottir, Inga; Steingrimsdottir, Laufey

    2012-01-01

    .... The aim of this study was to assess selenium in the diet and whole blood of adolescent girls, as well as define the most important foods contributing to intake and blood concentrations of selenium...

  16. Selenium exposure by food sources. impact into human health due selenium deficiency as well as selenium excess

    OpenAIRE

    Ivanov Iliev, Angel

    2012-01-01

    Selenium is important micronutrient with great impact into human health. In mammal metabolism it is included as coenzyme in several key enzymes. There are 35 selenoproteins identified, which role is not fully clarified yet. Selenium is well known both with its high toxicity and presence of several important diseases impacted by its deficiency. Selenium dosage is also a problem. Minimal daily required dose differs less than an order from maximum allowed daily intake. Northern Balkans is territ...

  17. PLANT RESOURCES BASED SELENIUM SUPPLEMENTATION IN DAILY NUTRITION

    OpenAIRE

    Vida Škrabanja

    2017-01-01

    Selenium is one of the essential elements that has a direct effect on human health and disease. Environmental conditions and agricultural practice have a profound influence on the selenium content in plants. Cultivation of plants enriched with the selenium has an effective potential for selenium supplementation in diets for population which is exposed to selenium deficiency. Bioavailability of selenium compounds from food is in strong correlation with the source and its chemical form. The sel...

  18. Meaning and resource of selenium in human nutrition

    OpenAIRE

    KRATOCHVÍLOVÁ, Zuzana

    2014-01-01

    Bachelor's thesis concentrates on functions of selenium in human nutrition. Selenium is an essential trace element of importance to human health. Its availability depends on the concentration of selenium in the soil. The average income of selenium in the Czech population are usually 36 g/day per individuals. Excess or insufficient selenium intakes can result in adverse effects on human health. The most important sources of selenium in the diets of most people are meat, fish, eggs, milk, cerea...

  19. Selenium. Role of the essential metalloid in health.

    Science.gov (United States)

    Kurokawa, Suguru; Berry, Marla J

    2013-01-01

    Selenium is an essential micronutrient in mammals, but is also recognized as toxic in excess. It is a non-metal with properties that are intermediate between the chalcogen elements sulfur and tellurium. Selenium exerts its biological functions through selenoproteins. Selenoproteins contain selenium in the form of the 21st amino acid, selenocysteine (Sec), which is an analog of cysteine with the sulfur-containing side chain replaced by a Se-containing side chain. Sec is encoded by the codon UGA, which is one of three termination codons for mRNA translation in non-selenoprotein genes. Recognition of the UGA codon as a Sec insertion site instead of stop requires a Sec insertion sequence (SECIS) element in selenoprotein mRNAs and a unique selenocysteyl-tRNA, both of which are recognized by specialized protein factors. Unlike the 20 standard amino acids, Sec is biosynthesized from serine on its tRNA. Twenty-five selenoproteins are encoded in the human genome. Most of the selenoprotein genes were discovered by bioinformatics approaches, searching for SECIS elements downstream of in-frame UGA codons. Sec has been described as having stronger nucleophilic and electrophilic properties than cysteine, and Sec is present in the catalytic site of all selenoenzymes. Most selenoproteins, whose functions are known, are involved in redox systems and signaling pathways. However, several selenoproteins are not well characterized in terms of their function. The selenium field has grown dramatically in the last few decades, and research on selenium biology is providing extensive new information regarding its importance for human health.

  20. Selenium. Role of the Essential Metalloid in Health

    Science.gov (United States)

    Kurokawa, Suguru; Berry, Marla J.

    2015-01-01

    Selenium is an essential micronutrient in mammals, but is also recognized as toxic in excess. It is a non-metal with properties that are intermediate between the chalcogen elements sulfur and tellurium. Selenium exerts its biological functions through selenoproteins. Selenoproteins contain selenium in the form of the 21st amino acid, selenocysteine (Sec), which is an analog of cysteine with the sulfur-containing side chain replaced by a Se-containing side chain. Sec is encoded by the codon UGA, which is one of three termination codons for mRNA translation in non-selenoprotein genes. Recognition of the UGA codon as a Sec insertion site instead of stop requires a Sec insertion sequence (SECIS) element in selenoprotein mRNAs and a unique selenocysteyl-tRNA, both of which are recognized by specialized protein factors. Unlike the 20 standard amino acids, Sec is biosynthesized from serine on its tRNA. Twenty-five selenoproteins are encoded in the human genome. Most of the selenoprotein genes were discovered by bioinformatics approaches, searching for SECIS elements downstream of in-frame UGA codons. Sec has been described as having stronger nucleophilic and electrophilic properties than cysteine, and Sec is present in the catalytic site of all selenoenzymes. Most selenoproteins, whose functions are known, are involved in redox systems and signaling pathways. However, several selenoproteins are not well characterized in terms of their function. The selenium field has grown dramatically in the last few decades, and research on selenium biology is providing extensive new information regarding its importance for human health. PMID:24470102

  1. The influence of selenium supplementation of animal feed on human selenium intake in Serbia

    OpenAIRE

    Pavlović Z.; Miletić I.; Jokić Ž.; Stevanović J.; Šobajić S.; Bulat Z.

    2013-01-01

    The use of selenium as animal feed supplement in Serbia was approved in 1989 for some categories of pigs, sheep and poultry. From 2000 selenium in animal feed became a requirement for all categories of farm animals. The aim of this study was to determine the consumption of selenium by Serbian livestock and in poultry production between 1990-1991 and 2000-2008 and to analyze the selenium content of meat, milk and eggs sold on Serbian markets to gain insight ...

  2. Baseline Selenium Status and Effects of Selenium and Vitamin E Supplementation on Prostate Cancer Risk

    OpenAIRE

    Kristal, AR; Darke, AK; Morris, JS; Tangen, CM; Goodman, PJ; Thompson, IM; Meyskens, FL; Goodman, Ge; Minasian, LM; Parnes, HL; Lippman, SM; Klein, EA

    2014-01-01

    Background The Selenium and Vitamin E Cancer Prevention Trial found no effect of selenium supplementation on prostate cancer (PCa) risk but a 17% increased risk from vitamin E supplementation. This case-cohort study investigates effects of selenium and vitamin E supplementation conditional upon baseline selenium status. Methods There were 1739 total and 489 high-grade (Gleason 7-10) PCa cases and 3117 men in the randomly selected cohort. Proportional hazards models estimated hazard ratios (HR...

  3. Seleksi khamir yang berbasis selenium sebagai sumber bahan bioaktif dan uji modulasi apoptosis seluler Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Titin Yulinery

    2012-02-01

    Full Text Available The selection of yeast from volcanic soil as bioactive source based on selenium and apoptosis modulation of Saccharomyces cerevisiae have been done. Isolation of yeast used the dilution method. Furthermore, the isolates were selected for resistance and accumulation test of selenium, catalyze test, resistance to high temperature and test of toxicity to garlic. The Inhibition activity was detected by using paper disc method. The result showed that 11 isolates from Kerinci and 4 isolates from Rinjani had been determined. 10 isolates were resistant to SeO2 toxicity, could accumulate Se, and had the activity of catalyze. Isolates 15 and 394.1 were sensitive to garlic toxicity, could inhibit 3.71 cm and 4.16 cm, respectively. All the isolates collected were mesophylic, and could grow at the temperature 28 €“30 °C. The highest Se concentration of the isolates was 0.92 ppm and 0.78 ppm, which produced by isolate 53 and 15 respectively. Isolate 15 were lower than isolate 53 in apoptosis modulation yeast LIPIMC strain and yeast BJ 3505 strain (10.54% and 14.24%, respectively. The highest frequent of petite was BJ 3505 strain.

  4. Efficacy of selenium from hydroponically produced selenium-enriched kale sprout (Brassica oleracea var. alboglabra L.) in broilers.

    Science.gov (United States)

    Chantiratikul, Anut; Pakmaruek, Pornpan; Chinrasri, Orawan; Aengwanich, Worapol; Chookhampaeng, Sumalee; Maneetong, Sarunya; Chantiratikul, Piyanete

    2015-05-01

    An experiment was conducted to determine the efficacy of Se from hydroponically produced Se-enriched kale sprout (HPSeKS) on performance, carcass characteristics, tissue Se concentration, and physiological responses of broilers in comparison to that of Se from Se-enriched yeast and sodium selenite. Three hundred and sixty male broilers, 10 days of age, were assigned to 6 groups, 4 replicates of 15 broilers each, according to the completely randomized design. The dietary treatments were the following: T1: control diet; T2: control diet plus 0.3 mg Se/kg from sodium selenite; T3: control diet plus 0.3 mg Se/kg from Se-enriched yeast; and T4, T5, and T6: control diet plus 0.3, 1.0, and 2.0 mg Se/kg from HPSeKS, respectively. The results found that dietary Se supplementation did not (p > 0.05) alter performance and carcass characteristics of broilers. Se supplementation increased (p < 0.05) Se concentrations in the liver and kidney of broilers. Heart tissue Se concentration of broilers fed Se from sodium selenite was lower (p < 0.05) than that of broilers fed Se from HPSeKS and Se-enriched yeast. Selenium from HPSeKS increased higher (p < 0.05) GSH-Px activity when compared to Se from sodium selenite and Se-enriched yeast. The results indicated that the efficacy of Se from HPSeKS was comparable in increasing tissue Se concentration, but higher in improving GSH-Px activity in Rbc when compared to those of Se from Se-enriched yeast.

  5. The mechanism of improved intracellular organic selenium and glutathione contents in selenium-enriched Candida utilis by acid stress.

    Science.gov (United States)

    Zhang, Gao-Chuan; Wang, Da-Hui; Wang, Dong-Hua; Wei, Gong-Yuan

    2017-03-01

    Batch culture of Candida utilis CCTCC M 209298 for the preparation of selenium (Se)-enriched yeast was carried out under different pH conditions, and maximal intracellular organic Se and glutathione (GSH) contents were obtained in a moderate acid stress environment (pH 3.5). In order to elucidate the physiological mechanism of improved performance of Se-enriched yeast by acid stress, assays of the key enzymes involved in GSH biosynthesis and determinations of energy supply and regeneration were performed. The results indicated that moderate acid stress increased the activity of γ-glutamylcysteine synthetase and the ratios of NADH/NAD(+) and ATP/ADP, although no significant changes in intracellular pH were observed. In addition, the molecular mechanism of moderate acid stress favoring the improvement of Se-yeast performance was revealed by comparing whole transcriptomes of yeast cells cultured at pH 3.5 and 5.5. Comparative analysis of RNA-Seq data indicated that 882 genes were significantly up-regulated by moderate acid stress. Functional annotation of the up-regulated genes based on gene ontology and the Kyoto Encyclopedia of Genes and Genome (KEGG) pathway showed that these genes are involved in ATP synthesis and sulfur metabolism, including the biosynthesis of methionine, cysteine, and GSH in yeast cells. Increased intracellular ATP supply and more amounts of sulfur-containing substances in turn contributed to Na2SeO3 assimilation and biotransformation, which ultimately improved the performance of the Se-enriched C. utilis.

  6. Toxicology evaluation of selenium protein powder

    Directory of Open Access Journals (Sweden)

    Qin Shunyi

    2017-01-01

    Full Text Available The experiment was conducted to evaluate the safety of selenium protein powder, a novel organic selenium nutritional supplement, and reported corresponding data and results based on a series of toxicological tests. It was examined to evaluate oral acute toxicity by median lethal dose test and mutagenic potential by bone marrow cell micronucleus test and sperm abnormality test using Kun-Ming mice. The results showed that the oral LD50 of selenium protein powder exceeded 31.25 g/kg body weight in mice. No mutagenicity was found by mouse bone marrow cell micronucleus test and mouse sperm abnormality test. The results suggested greater safety of selenium protein powder as a nutritional selenium supplement, and selenium protein powder has the potential for development and application in food systems or functional foods.

  7. Vaginal Yeast Infections

    Science.gov (United States)

    ... Yeast Infections Print A A A en español Infecciones vaginales por hongos What Are Vaginal Yeast Infections? ... keep the amount in a person's body under control. But yeast in the vagina can sometimes "overgrow" ...

  8. Yeast Infection (Vaginal)

    Science.gov (United States)

    ... vaginal discharge with a cottage cheese appearance Complicated yeast infection You might have a complicated yeast infection ... have an uncomplicated or a complicated infection. Uncomplicated yeast infection For mild to moderate symptoms and infrequent ...

  9. Effect of in utero-administered coumestrol, equol, and organic selenium on biomarkers for phase 2 enzyme capacity and redox status

    DEFF Research Database (Denmark)

    Kramer, F.; Jensen, P. S.; Vinggaard, Anne

    2003-01-01

    -transferase (GST), quinone reductase (QR), or RBC glutathione peroxidase (GP(x)) in the offspring, whereas significant increases in GST QR, and GP(x) activities in dams were observed following administration of selenium-enriched yeast. The level of 17beta-estradiol in offspring from coumestrol-exposed dams...

  10. Selenium in Oncology: From Chemistry to Clinics

    OpenAIRE

    Oliver Micke; Lutz Schomburg; Jens Buentzel; Klaus Kisters; Ralph Muecke

    2009-01-01

    The essential trace element selenium, which is a crucial cofactor in the most important endogenous antioxidative systems of the human body, is attracting more and more the attention of both laypersons and expert groups. The interest of oncologists mainly focuses in the following clinical aspects: radioprotection of normal tissues, radiosensitizing in malignant tumors, antiedematous effect, prognostic impact of selenium, and effects in primary and secondary cancer prevention. Selenium is a con...

  11. Selenium accumulation in the cockle Anadara trapezia

    Energy Technology Data Exchange (ETDEWEB)

    Jolley, Dianne F. [GEOQUEST, Department of Chemistry, University of Wollongong, NSW 2522 (Australia)]. E-mail: djolley@uow.edu.au; Maher, William A. [Ecochemistry Laboratory, Division of Science and Design, University of Canberra ACT 2601 (Australia); Kyd, Jennelle [Immunological Research Group, Division of Science and Design, University of Canberra ACT 2601 (Australia)

    2004-11-01

    An extensive study on Se accumulation in a population of Anadara trapezia from a marine lake is reported. The effects of organism mass, gender, reproductive cycle, and season on Se accumulation and tissue distribution were investigated. Analyses showed that gender and reproductive cycle had no significant effect on Se accumulation. A. trapezia showed a strong positive correlation between Se burden and tissue mass. Constant Se concentrations were observed within individual populations but varied spatially with sediment Se concentrations. Se concentrations in tissues decreased from gills > gonad/intestine > mantle > muscle > foot, which remained constant over 12 months, however, significantly lower concentrations were observed in the summer compared to winter. A. trapezia is a good biomonitor for Se, as gender and size do not effect concentration, however, season of collection must be reported if changes in Se bioavailability are to be identified in short term studies, or during intersite comparisons. - Capsule: The marine bivalve Anadara trapezia is a good bioindicator for marine selenium contamination.

  12. How to use the world's scarce selenium resources efficiently to increase the selenium concentration in food.

    Science.gov (United States)

    Haug, Anna; Graham, Robin D; Christophersen, Olav A; Lyons, Graham H

    2007-12-01

    The world's rare selenium resources need to be managed carefully. Selenium is extracted as a by-product of copper mining and there are no deposits that can be mined for selenium alone. Selenium has unique properties as a semi-conductor, making it of special value to industry, but it is also an essential nutrient for humans and animals and may promote plant growth and quality. Selenium deficiency is regarded as a major health problem for 0.5 to 1 billion people worldwide, while an even larger number may consume less selenium than required for optimal protection against cancer, cardiovascular diseases and severe infectious diseases including HIV disease. Efficient recycling of selenium is difficult. Selenium is added in some commercial fertilizers, but only a small proportion is taken up by plants and much of the remainder is lost for future utilization. Large biofortification programmes with selenium added to commercial fertilizers may therefore be a fortification method that is too wasteful to be applied to large areas of our planet. Direct addition of selenium compounds to food (process fortification) can be undertaken by the food industry. If selenomethionine is added directly to food, however, oxidation due to heat processing needs to be avoided. New ways to biofortify food products are needed, and it is generally observed that there is less wastage if selenium is added late in the production chain rather than early. On these bases we have proposed adding selenium-enriched, sprouted cereal grain during food processing as an efficient way to introduce this nutrient into deficient diets. Selenium is a non-renewable resource. There is now an enormous wastage of selenium associated with large-scale mining and industrial processing. We recommend that this must be changed and that much of the selenium that is extracted should be stockpiled for use as a nutrient by future generations.

  13. Review on Nano SeleniumProduced by Bacteria

    Directory of Open Access Journals (Sweden)

    LI Ji-xiang

    2014-12-01

    Full Text Available Selenium (Se is a kind of essential trace element for people and animal, while ionic state of selenium is toxic with high concentrations and will cause the selenium pollution. Nano-selenium is stable, nontoxic with higher biological activity. Application of bacteria reducing selenite or selenate to biological nano-selenium has great potential in selenium pollution control and nano-selenium production. This review summarizes the research progress of the red elemental nano-selenium reduced by bacteria including characteristics and application of nano-selenium, effects of carbon and nitrogen source, oxygen, temperature and pH in bacteria nano-selenium production, and molecular mechanisms of nano-selenium reduced by bacteria.

  14. Selenium Biochemistry and Bioavailability: Implications for Animal Agriculture

    Directory of Open Access Journals (Sweden)

    Shaniko Shini

    2015-12-01

    Full Text Available Selenium (Se is an essential trace mineral required for growth, development, immune function, and metabolism. Selenium exerts its biological effects as an integral component of selenoproteins (SePs. Deficiency or low Se status leads to marked changes in many biochemical pathways and a range of pathologies and disorders which are associated with SeP function. Animals, and presumably humans, are able to efficiently utilize nutritionally adequate levels of Se in both organic and inorganic forms. It is now clear that the bioavailability of Se varies depending on the source and chemical form of the Se supplement. There are a range of products available for dietary Se supplementation, however, organic sources have been shown to be assimilated more efficiently than inorganic compounds and are considered to be less toxic and more appropriate as a feed supplement. Yeast enriched with Selenohomoalanthionine (SeHLan has recently become commercially available, and initial research suggests that it may be an efficacious source for the production of Se enriched animal products.

  15. Effects of selenium on ischaemia-reperfusion injury in a rat testis model.

    Science.gov (United States)

    Kara, Ö; Sari, E; Akşit, H; Yay, A; Akşit, D; Dönmez, M I

    2016-12-01

    Selenium is shown to have beneficial effects on ischaemia-reperfusion (IR) injury. Our aim was to assess the effects of selenium on IR-induced testicular damage in terms of biochemical and histopathological evaluation. A total of 32 rats were randomised into four groups: control, IR, IR + selenium (IR + S) and S. Detorsion was applied after 3 h of torsion. Testicular tissue superoxide dismutase (SOD), glutathione (GSH), malondialdehyde (MDA), total antioxidant capacity (TAC) and DNA fragmentation levels were determined. Testicular tissue samples were examined by histopathological examination and terminal deoxynucleotidyl transferase dUTP nick end-labelling staining. The control, IR and IR + S groups had higher SOD values compared with the S group; SOD levels of the control and IR + S groups were higher than those of the IR group (P selenium possibly reduces oxidative stress and apoptosis caused by testicular IR injury in rats. The testicular protective effect of selenium appears to be mediated through its anti-apoptotic and antioxidative effects. However, selenium does not affect DNA fragmentation. © 2016 Blackwell Verlag GmbH.

  16. Effect of short-term feeding duration of diets containing commercial whole-cell yeast or yeast subcomponents on immune function and disease resistance in channel catfish, Ictalurus punctatus.

    Science.gov (United States)

    Welker, T L; Lim, C; Yildirim-Aksoy, M; Klesius, P H

    2012-04-01

    Juvenile channel catfish, Ictalurus punctatus, were fed diets supplemented with yeast or yeast subcomponents (YYS) as commercial preparations of β-glucan (MacroGard(®) and Betagard A(®)), mannan oligosaccharide (Bio-Mos(®) Aqua Grade), or whole-cell Saccharomyces cerevisiae (Levucell SB20(®)) at the manufacturers' recommended levels. Fish were fed experimental diets for 1 or 2 weeks prior to disease challenge (pre-challenge feeding periods) and sampled at the end of each feeding period to measure haematological and immune parameters and to determine the effects of dietary YYS on resistance to Edwardsiella ictaluri, the causative agent of enteric septicaemia disease (ESC). Feeding of experimental diets continued for 3 weeks post-challenge. In channel catfish fed diets supplemented with MacroGard(®), Betagard A(®), or Levucell SB20(®), survival in the 1 week pre-challenge feeding group and antibody titres in the 2 week feeding group were significantly higher post-E. ictaluri challenge in relation to catfish fed with the control diet. In fish fed these same three diets, survival to ESC was significantly higher after 1 week vs. 2 weeks feeding, while the antibody response was significantly higher after 2 weeks vs. 1 week. Lysozyme activity was also higher in the 1 week feeding group, but the increased activity was unrelated to diet. Feeding YYS-supplemented diets for a shorter duration of 1 week prior to challenge may prove beneficial in increasing resistance to ESC in channel catfish. However, we cannot discount that feeding YYS diets during the recovery period may have contributed to 'glucan overload' and reduced survival in the 2 week feeding group. Published 2011. This article is a US Government work and is in the public domain in the US.

  17. Effects of selenomethionine supplementation on selenium status and thyroid hormone concentrations in healthy adults1234

    Science.gov (United States)

    Midthune, Douglas N; Patterson, Kristine Y; Canfield, Wesley K; Hill, A David; Levander, Orville A; Taylor, Philip R; Moler, James E; Patterson, Blossom H

    2009-01-01

    Background: Selenium, a potential cancer prevention agent currently being tested against prostate cancer in the Selenium and Vitamin E Cancer Prevention Trial (SELECT), plays an integral role in thyroid metabolism. The effects of long-term selenium supplementation on thyroid hormone concentrations are unknown. Objective: The objective was to investigate the effects of long-term selenium supplementation on thyroid hormone concentrations. Design: Twenty-eight healthy adults took 200 μg selenomethionine/d for 28 mo. The thyroid hormones triiodothyronine (T3), thyroxine (T4), and thyrotropin (TSH) were measured in plasma for 4 mo before supplementation and quarterly during supplementation. The assay methods were changed midstudy; the results of the 2 methods were not comparable. Therefore, one analysis was conducted based on the results of the first method, and a second analysis was based on all of the data, adjusted for the change. Serial data collection permitted a test for trends rather than simply a difference between initial and final values. Results: By 9 mo, mean (±SEM) plasma selenium concentrations had increased from 1.78 ± 0.07 μmol/L at baseline to 2.85 ± 0.11 μmol/L for men and from 1.64 ± 0.04 to 3.32 ± 0.1.2 μmol/L for women. T3 concentrations in men increased 5% per year (P = 0.01). T4 and TSH concentrations were unchanged. Conclusions: Selenium supplementation produced no clinically significant changes in thyroid hormone concentrations. A small but statistically significant increase in T3 concentrations was noted in men, with no corresponding decreases in TSH. A subset of SELECT subjects might be monitored periodically for changes during long-term selenium supplementation. PMID:19403637

  18. Assessment of requirements for selenium and adequacy of selenium status: a review.

    Science.gov (United States)

    Thomson, C D

    2004-03-01

    The intent of this review is to evaluate the scientific evidence for the assessment of adequacy of selenium status and of the requirements for selenium. From this evidence, attempts have been made to define levels of plasma selenium and dietary selenium intake, which could be used for the assessment of deficiency or adequacy of selenium status. The first section briefly reviews the methods for assessment of selenium status. The second section outlines the requirements for selenium based on a number of criteria, and how these have been translated into recommended intakes of selenium. In the final section, levels of plasma selenium and dietary intake based on different criteria of adequacy have been proposed. The minimum requirement for selenium is that which prevents the deficiency disease, Keshan disease. The recommended intakes of selenium have been calculated from the requirement for optimum plasma glutathione peroxidase (GPx) activity that must, because of the hierarchy of selenoproteins, also take account of the amounts needed for normal levels of other biologically necessary selenium compounds. Whether optimal health depends upon maximization of GPx or other selenoproteins, however, has yet to be resolved, and the consequences of less-than-maximal GPx activities or mRNA levels need investigation. Intakes, higher than recommended intakes, and plasma selenium concentrations that might be protective for cancer or result in other additional health benefits have been proposed. There is an urgent need for more large-scale trials to assess any such beneficial effects and to provide further data on which to base more reliable estimates for intakes and plasma selenium levels that are protective.

  19. Learning selenium testing tools with Python

    CERN Document Server

    Gundecha, Unmesh

    2014-01-01

    If you are a quality testing professional, or a software or web application developer looking to create automation test scripts for your web applications, with an interest in Python, then this is the perfect guide for you. Python developers who need to do Selenium testing need not learn Java, as they can directly use Selenium for testing with this book.

  20. DIETARY SELENIUM AND COPPER INTAKE BY RESIDENT ...

    African Journals Online (AJOL)

    hi-tech

    2004-01-01

    Jan 1, 2004 ... Ph.D., Senior Research Fellow and Head, Nutrition Unit, Noguchi Memorial Institute for Medical Research, University of Ghana and P. Amankwa, ... Objectives: To determine and evaluate dietary intake of selenium and copper by resident undergraduate ... number of Selenium-dependent enzymes known as.

  1. Immunomodulatory effect of dietary selenium supplementation on ...

    African Journals Online (AJOL)

    Effect of selenium supplementation on the immune response of Trypanosoma brucei brucei infected rats was investigated. Twenty five (25) adult male albino rats divided into five groups of five rats each were used for this study. Groups A, B and C were fed 4, 8 and 16 part per million (ppm) selenium in their feed, respectively ...

  2. Understanding selenium biogeochemistry in engineered ecosystems

    NARCIS (Netherlands)

    Jain, Rohan; Hullebusch, Van Eric D.; Lenz, Markus; Farges, François

    2017-01-01

    Selenium is used extensively in many industries, and it is necessary for human nutrition. On the other hand, it is also toxic at slightly elevated concentrations. With the advent of industrialisation, selenium concentrations in the environment due to anthropogenic activities have increased.

  3. Changing selenium nutritional status of Chinese residents

    Science.gov (United States)

    China has been designated as one of 40 countries deficient in selenium (Se) according to the World Health Organization. Selenium concentrations in hair are commonly used to evaluate the Se level of the human body. Moreover, hair Se concentrations are significantly correlated with Se concentrations ...

  4. Comparative effects of two different forms of selenium on oxidative stress biomarkers in healthy men: a randomized clinical trial

    Science.gov (United States)

    Richie, John P.; Das, Arun; Calcagnotto, Ana M.; Sinha, Raghu; Neidig, Wanda; Liao, Jiangang; Lengerich, Eugene J.; Berg, Arthur; Hartman, Terryl J.; Ciccarella, Amy; Baker, Aaron; Kaag, Matthew G.; Goodin, Susan; DiPaola, Robert S.; El-Bayoumy, Karam

    2014-01-01

    Epidemiological and laboratory studies indicate that dietary selenium protects against prostate cancer. Results from clinical trials suggest that selenium-enriched yeast (SY) but not selenomethionine (SeMet) may be effective at reducing prostate cancer risk. Our objectives were to directly compare for the first time the effects of SeMet and SY on prostate cancer relevant biomarkers in men. We performed a randomized double blind, placebo-controlled trial of SY (200 or 285 µg/day) and SeMet (200 µg/day) administered for 9 months in 69 healthy men. Primary endpoints included blood levels of selenium-containing compounds and oxidative stress biomarkers (urine 8-hydroxy-2’-deoxyguanosine [8-OHdG] and 8-iso-prostaglandin-F2α [8-iso-PGF2α] and blood glutathione [GSH]). Secondary endpoints included plasma glucose and PSA levels. Compliance was high in all groups (>95%). Plasma selenium levels were increased 93%, 54%, and 86% after 9 months in SeMet and low and high dose SY groups, respectively, and returned to baseline levels after a 3 month washout (Pselenium (supplementation with SY but not SeMet in healthy men. These findings suggest that selenium-containing compounds other than SeMet may account for the decrease in oxidative stress. PMID:24938534

  5. The Role of Selenium in Human Immunity | Chisenga | Medical ...

    African Journals Online (AJOL)

    ... including selenium deficiency, so it has been postulated that selenium has a role in immune function. Immune dysfunction, susceptibility to viral infections and increased mortality are some of the outcomes associated with selenium deficiency. Key Words: Selenium; Human; Cell-mediated immunity; Innate immunity; HIV; ...

  6. Selenium: a micronutrient essential for maintaining human health

    OpenAIRE

    GONCA, Süheyla

    2014-01-01

    Selenium is an fundamental importance to human health. It is an essential trace element for major metabolic pathways, since selenium is an essential component of Glutathione peroxidase enzyme. Diet is the main source of selenium. Selenoproteins in mammalian cells indicated that essential role of selenium in the bodys antioxidant defense system.

  7. Phase 3 clinical trial investigating the effect of selenium supplementation in men at high-risk for prostate cancer.

    Science.gov (United States)

    Algotar, Amit M; Stratton, M Suzanne; Ahmann, Frederick R; Ranger-Moore, James; Nagle, Raymond B; Thompson, Patricia A; Slate, Elizabeth; Hsu, Chiu H; Dalkin, Bruce L; Sindhwani, Puneet; Holmes, Michael A; Tuckey, John A; Graham, David L; Parnes, Howard L; Clark, Lawrence C; Stratton, Steven P

    2013-02-15

    This study was conducted to investigate the effect of Se supplementation on prostate cancer incidence in men at high risk for prostate cancer. A Phase 3 randomized, double-blind, placebo-controlled clinical trial was conducted in 699 men at high risk for prostate cancer (prostate specific antigen (PSA) >4 ng/ml and/or suspicious digital rectal examination and/or PSA velocity >0.75 ng/ml/year), but with a negative prostate biopsy. Participants were randomized to receive daily oral placebo (N = 232), 200 µg selenium (N = 234), or 400 µg selenium (N = 233) as selenized yeast. They were followed every 6 months for up to 5 years. The time to diagnosis of prostate cancer was compared between treatment groups using the Cox proportional hazards model. Compared to placebo, the hazard ratios [95% confidence intervals] for risk of developing prostate cancer in the selenium 200 µg/day or the selenium 400 µg/day group were 0.94 [0.52, 1.7] and 0.90 [0.48, 1.7], respectively. PSA velocity in the selenium arms was not significantly different from that observed in the placebo group (P = 0.18 and P = 0.17, respectively). Selenium supplementation appeared to have no effect on the incidence of prostate cancer in men at high risk. In conjunction with results of other studies, these data indicate that selenium supplementation may not have a role in prostate cancer chemoprevention. Copyright © 2012 Wiley Periodicals, Inc.

  8. Structural and electrical properties of selenium nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, Prajna, E-mail: prajna111@gmail.com [Department of Physics, Visva-Bharati, Santiniketan, 731235 (India); Department of Physics, Bolpur College, Bolpur, 731204 (India); Konar, Shyamal [Department of Physics, Visva-Bharati, Santiniketan, 731235 (India); Gupta, Bikash C., E-mail: bikashc.gupta@visva-bharati.ac.in [Department of Physics, Visva-Bharati, Santiniketan, 731235 (India)

    2016-01-08

    The electronic structure calculations are systematically carried out within the density functional formalism for understanding the structural and electronic properties of a number of selenium nanotubes. In particular, single walled selenium nanotubes (achiral) are studied in this work. Our investigations reveal that the lower diameter nanotubes are unstable. Beyond certain diameter, the tubes retain their tubular structure and they show metallic property. Furthermore, work-functions of these tubes are found to depend on their diameters and differ from that of the bulk selenium surface. - Highlights: • The selenium tubes become stable and retain tubular shape beyond certain diameter. • In contrary to bulk selenium, the tubular structures show metallic property. • The work-functions of tubes vary with diameter. The amount of variation is 1.2 eV.

  9. Selenium supplementation induces mitochondrial biogenesis in trophoblasts.

    Science.gov (United States)

    Khera, Alisha; Dong, Lan-Feng; Holland, Olivia; Vanderlelie, Jessica; Pasdar, Elham A; Neuzil, Jiri; Perkins, Anthony V

    2015-08-01

    Placental oxidative stress has been implicated in pregnancy complications and previous work has shown that selenium can protect trophoblast mitochondria from oxidative stress. This report examines mitochondrial function and content in trophoblasts supplemented with selenium. Swan-71, JEG-3 and BeWo cells and placental tissue were incubated with sodium selenite or selenomethionine. Mitochondrial function was examined in a respirometer. Mitochondrial content was determined using RT-PCR. The levels of the mitochondrial biogenesis markers selenoprotein H, PGC-1α and NRF-1 was examined by western blotting. Mitochondrial respiration was significantly enhanced post selenium supplementation in cells and tissues. Selenium supplementation increased mitochondrial content and up-regulated mitochondrial biogenesis mediators in cells. These results emphasise the importance of selenium in mitochondrial regeneration in trophoblasts. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Prions in yeast

    OpenAIRE

    Bezdíčka, Martin

    2013-01-01

    The thesis describes yeast prions and their biological effects on yeast in general. It defines the basic characteristics of yeast prions, that distinguish prions from other proteins. The thesis introduces various possibilities of prion formation, and propagation as well as specific types of yeast prions, including various functions of most studied types of prions. The thesis also focuses on chaperones that affect the state of yeast prions in cells. Lastly, the thesis indicates similarities be...

  11. Distribution of selenium in zebrafish larvae after exposure to organic and inorganic selenium forms.

    Science.gov (United States)

    Dolgova, N V; Hackett, M J; MacDonald, T C; Nehzati, S; James, A K; Krone, P H; George, G N; Pickering, I J

    2016-03-01

    Selenium is an essential micronutrient for many organisms, and in vertebrates has a variety of roles associated with protection from reactive oxygen species. Over the past two decades there have been conflicting reports upon human health benefits and detriments arising from consumption of selenium dietary supplements. Thus, early studies report a decrease in the incidence of certain types of cancer, whereas subsequent studies did not observe any anti-cancer effect, and adverse effects such as increased risks for type 2 diabetes have been reported. A possible contributing factor may be that different chemical forms of selenium were used in different studies. Using larval stage zebrafish (Danio rerio) as a model organism, we report a comparison of the toxicities and tissue selenium distributions of four different chemical forms of selenium. We find that the organic forms of selenium tested (Se-methyl-l-selenocysteine and l-selenomethionine) show considerably more toxicity than inorganic forms (selenite and selenate), and that this appears to be correlated with the level of bioaccumulation. Despite differences in concentrations, the tissue specific pattern of selenium accumulation was similar for the chemical forms tested; selenium was found to be highly concentrated in pigment (melanin) containing tissues especially for the organic selenium treatments, with lower concentrations in eye lens, yolk sac and heart. These results suggest that pigmented tissues might serve as a storage reservoir for selenium.

  12. Analyses of selenotranscriptomes and selenium concentrations in response to dietary selenium deficiency and age reveal common and distinct patterns by tissue and sex in telomere-dysfunctional mice

    Science.gov (United States)

    Background: While sex and aging are known to impact mRNA abundance of several selenoproteins, this has not been examined comprehensively or in aged mice. By employing telomerase RNA component knockout (Terc-/-) mice carrying humanized telomeres, long-term dietary selenium (Se) deprivation has recent...

  13. Blood selenium levels and contribution of food groups to selenium intake in adolescent girls in Iceland

    Directory of Open Access Journals (Sweden)

    Ingibjorg Gunnarsdottir

    2012-08-01

    Full Text Available Background/objectives: Significant changes have been reported in dietary habits and food availability in Iceland that would be expected to compromise selenium intake and status, especially among young people. These include substantial decreases in the consumption of fish and milk, as well as the selenium content of imported wheat. The aim of this study was to assess selenium in the diet and whole blood of adolescent girls, as well as define the most important foods contributing to intake and blood concentrations of selenium. Design: The subjects were 96 randomly selected girls, aged 16–20, who answered a validated food frequency questionnaire (FFQ for dietary assessment. Selenium intake from each food group was calculated in µg/day. Blood samples were collected for measurement of whole blood selenium. Results: Mean dietary selenium was 51±25 µg/day. Milk/dairy products, including cheese, contributed 36±14% of total dietary selenium; fish 18±12%; and bread/cereal products 13±6%. Mean whole blood selenium was 117±12 µg/l (range 90–208; nearly 90% of subjects were above the optimal level of 100 µg/l. Fish and bread/cereal products were the only foods significantly correlated with selenium in blood (r=0.32; P = 0.002 and r=0.22; P = 0.04, respectively while no correlation was found with milk and dairy products in spite of their greater contribution to total selenium intake. Conclusion: In this population of Icelandic adolescent girls, selenium intake and status seem acceptable. Judging from associations between intake and blood levels, fish and cereals may be the most important contributors to blood selenium.

  14. Selenium in oncology: from chemistry to clinics.

    Science.gov (United States)

    Micke, Oliver; Schomburg, Lutz; Buentzel, Jens; Kisters, Klaus; Muecke, Ralph

    2009-10-12

    The essential trace element selenium, which is a crucial cofactor in the most important endogenous antioxidative systems of the human body, is attracting more and more the attention of both laypersons and expert groups. The interest of oncologists mainly focuses in the following clinical aspects: radioprotection of normal tissues, radiosensitizing in malignant tumors, antiedematous effect, prognostic impact of selenium, and effects in primary and secondary cancer prevention. Selenium is a constituent of the small group of selenocysteine-containing selenoproteins and elicits important structural and enzymatic functions. Selenium deficiency has been linked to increased infection risk and adverse mood states. It has been shown to possess cancer-preventive and cytoprotective activities in both animal models and humans. It is well established that Se has a key role in redox regulation and antioxidant function, and hence in membrane integrity, energy metabolism and protection against DNA damage. Recent clinical trials have shown the importance of selenium in clinical oncology. Our own clinical study involving 48 patients suggest that selenium has a positive effect on radiation-associated secondary lymphedema in patients with limb edemas, as well as in the head and neck region, including endolaryngeal edema. Another randomized phase III study of our group was performed to examine the cytoprotective properties of selenium in radiation oncology. The aim was to evaluate whether sodium selenite is able to compensate a preexisting selenium deficiency and to prevent radiation induced diarrhea in adjuvant radiotherapy for pelvic gynecologic malignancies. Through this study, the significant benefits of sodium selenite supplementation with regards to selenium deficiency and radiotherapy induced diarrhea in patients with cervical and uterine cancer has been shown for the first time in a prospective randomized trial. Survival data imply that supplementation with selenium does not

  15. Selenium in Oncology: From Chemistry to Clinics

    Directory of Open Access Journals (Sweden)

    Oliver Micke

    2009-10-01

    Full Text Available The essential trace element selenium, which is a crucial cofactor in the most important endogenous antioxidative systems of the human body, is attracting more and more the attention of both laypersons and expert groups. The interest of oncologists mainly focuses in the following clinical aspects: radioprotection of normal tissues, radiosensitizing in malignant tumors, antiedematous effect, prognostic impact of selenium, and effects in primary and secondary cancer prevention. Selenium is a constituent of the small group of selenocysteine-containing selenoproteins and elicits important structural and enzymatic functions. Selenium deficiency has been linked to increased infection risk and adverse mood states. It has been shown to possess cancer-preventive and cytoprotective activities in both animal models and humans. It is well established that Se has a key role in redox regulation and antioxidant function, and hence in membrane integrity, energy metabolism and protection against DNA damage. Recent clinical trials have shown the importance of selenium in clinical oncology. Our own clinical study involving 48 patients suggest that selenium has a positive effect on radiation-associated secondary lymphedema in patients with limb edemas, as well as in the head and neck region, including endolaryngeal edema. Another randomized phase III study of our group was performed to examine the cytoprotective properties of selenium in radiation oncology. The aim was to evaluate whether sodium selenite is able to compensate a preexisting selenium deficiency and to prevent radiation induced diarrhea in adjuvant radiotherapy for pelvic gynecologic malignancies. Through this study, the significant benefits of sodium selenite supplementation with regards to selenium deficiency and radiotherapy induced diarrhea in patients with cervical and uterine cancer has been shown for the first time in a prospective randomized trial. Survival data imply that supplementation with

  16. Spectrophotometric Determination of Selenium Through Triiodide Anion.

    Science.gov (United States)

    Bizerea-Spiridon, Otilia; Nartita, Radu; Rogobete, Alexandru F; Negrea, Adina; Stroescu, Ramona; Bizerea, Teofana O; Ilie, Constantin; Marginean, Otilia

    2017-05-01

    Selenium is a chemical element found in the human body that plays a crucial role in its regulation. Depending on the concentration, it may have beneficial or have toxic effects. Selenium is incorporated as selenocysteine amino acid residue in selenoproteins which play an important role in many biological functions: anti-oxidant defense, regulation of the immune function and of the inflammatory response, metabolism of thyroid hormones, functioning of the central nervous system, biosynthesis of DNA and RNA, fertility, and reproduction. Excess selenium, altough less common than selenium deficiency, has equally important negative effects. Given the importance of selenium quantification in various samples, the study proposes a simple and direct spectrophotometric determination of selenium using triiodide anions. The method is based on the oxidation of iodide in acidic medium by selenium (IV) contained in the sample, to form elemental iodine which, in turn, reacts with the excess iodide to form the triiodide anions, the most stable soluble species in aqueous solution. Triiodide is colored from yellow to brown, depending on the concentration. The coloured compound has maximum absorbance at specific wavelengths and thus, the stage of interaction with a chromogenic agent is eliminated. Due to the sensitivity of the reaction, the detection limit of triiodide, and therefore selenium, is extended toward lower values. The optimal conditions for the measurements were established: λ = 290 nm, pH = 1.0 - 1.5, reaction time = 15 minutes. Two areas of selenium detection were determined from the samples: 0.025 - 0.100 ppm, and 0.1 - 4.0 ppm. The detection limit of selenium was lowered at 0.100 ppm and even at 0.025 ppm, which significantly improves the sensitivity of the determination. Types of samples were specified which are suitable for analysis using the proposed method and explained why, in case of biological fluids, it must be used only accompanied by an adequate digestion

  17. Fracture Phenomena in Amorphous Selenium

    DEFF Research Database (Denmark)

    Lindegaard-Andersen, Asger; Dahle, Birgit

    1966-01-01

    Fracture surfaces of amorphous selenium broken in flexure at room temperature have been studied. The fracture velocity was found to vary in different regions of the fracture surface. Peculiar features were observed in a transition zone between fast and slower fracture. In this zone cleavage steps...... with a nearly constant spacing of approximately 1 µ were found. Occasionally long cleavage whiskers—up to some millimeters long—were observed. Within certain regions the cleavage steps were crossed and interrupted by two line systems. The maximum fracture velocity has been measured to 350 m/sec. Further...

  18. Effects of dietary form of selenium on its distribution in eggs.

    Science.gov (United States)

    Čobanová, Klaudia; Petrovič, Vladimír; Mellen, Martin; Arpášova, Henrieta; Grešáková, L'ubomíra; Faix, Štefan

    2011-12-01

    The objective of this experiment was to investigate the selenium distribution in eggs from hens fed diets supplemented with Se from sodium selenite (SS) or selenium-enriched yeast (SY). One-day-old female chickens of Hy-Line Brown breed were randomly divided into four groups according to dietary treatments and, for the subsequent 9 months, were fed diets which differed only in the form or amount of Se supplemented. During the whole experiment, group 1 (control) was fed basal diet (BD) with only background Se level of 0.13 mg/kg dry matter (DM). Diets for groups 2 and 3 consisted of BD supplemented with an Se dose of 0.4 mg/kg DM either in the form of SS or SY, respectively. Group 4 was fed BD supplemented with 0.9 mg Se/kg DM from SY. After 9 months of dietary treatments, the Se levels in egg yolk and albumen from hens fed unsupplemented diet were almost identical whereas eggs from hens given diet supplemented with SS showed significantly higher Se deposition in yolk than in albumen (P doses 0.4 or 0.9 mg/kg DM from SY resulted in significantly higher Se concentration in albumen than in yolk (both P selenium deposition in eggs from hens given feed enriched with SY than from birds fed diet with equivalent SS dose. Regardless of dose and source, the selenium supplementation to feeds for groups 2, 3 and 4 resulted in significantly increased α-tocopherol concentration in egg yolk compared to control group 1 (P selenium sources.

  19. PLANT RESOURCES BASED SELENIUM SUPPLEMENTATION IN DAILY NUTRITION

    Directory of Open Access Journals (Sweden)

    Vida Škrabanja

    2017-01-01

    Full Text Available Selenium is one of the essential elements that has a direct effect on human health and disease. Environmental conditions and agricultural practice have a profound influence on the selenium content in plants. Cultivation of plants enriched with the selenium has an effective potential for selenium supplementation in diets for population which is exposed to selenium deficiency. Bioavailability of selenium compounds from food is in strong correlation with the source and its chemical form. The selenium of different sources and forms can become a part of human consumption when entering the food chain, wherein the inorganic forms of selenium are metabolized and converted to more available organic forms. Numerous results of systematic research of the selenium content in individual plant species as well as various techniques for producing selenium enriched foodstuffs is reviewed. The soil in Slovenia is selenium-poor and may concern a part of population which is potentially sensitive to selenium status. The merits of selenium effect, either alone or in combination with different environmental changes on plant production published by Slovenian authors are thus closely considered. Controversies continue to prevail regarding adequate amounts for selenium for health and disease prevention. Thus, general and individualized recommendations for selenium intake and supplementation in the future need to be cautiously followed and the reference values continually revised.

  20. Analysis of the selenium species distribution in cow blood by size exclusion liquid chromatography-inductively coupled plasma collision cell mass spectrometry (SEC-ICPccMS)

    Energy Technology Data Exchange (ETDEWEB)

    Palacios, Oscar; Encinar, Jorge Ruiz [Equipe de Chimie Analytique Bio-inorganique, Pau (France); Bertin, Gerard [Alltech, Regulatory Department, Paris (France); Lobinski, Ryszard [Equipe de Chimie Analytique Bio-inorganique, Pau (France); Warsaw University of Technology, Department of Analytical Chemistry, Warszawa (Poland)

    2005-10-01

    A method for performing rapid semiquantitative screening of the distribution of Se species in the blood of cows fed with a diet enriched in selenized yeast was optimized. The method was based on direct injection of a blood sample onto a high resolution size exclusion chromatographic column and fractionation of the selenium species. Selenium was detected on-line by ICP-MS with a collision cell. The concentrations of selenized haemoglobin and free selenomethionine were estimated using the chromatogram. The method was applied to a study involving 15 control and 15 treated dairy cows at four different supplementation time points. The increase in the selenomethionine and selenized haemoglobin was a linear function of the total selenium concentration. A threshold value of 600 ng ml{sup -1} of total Se was established beyond which selenomethionine could not be incorporated into the protein. No inorganic selenium was found to be present. The total selenium in cow blood correlated well with that in milk. The selenium supplementation did not change the protein distribution profiles for other essential elements (Cu,Fe,Mn,Zn). (orig.)

  1. In Situ Immobilization of Selenium in Sediment

    Energy Technology Data Exchange (ETDEWEB)

    Moore, Robert C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Stewart, Thomas Austin [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-09-01

    This project focused on the use of a sorbent, carbonated apatite, to immobilize selenium in the environment. It is know that apatite will sorb selenium and based on the mechanism of sorption it is theorized that carbonated apatite will be more effective that pure apatite. Immobilization of selenium in the environment is through the use of a sorbent in a permeable reactive barrier (PRB). A PRB can be constructed by trenching and backfill with the sorbent or in the case of apatite as the sorbent formed in situ using the apatite forming solution of Moore (2003, 2004). There is very little data on selenium sorption by carbonated apatite in the literature. Therefore, in this work, the basic sorptive properties of carbonated apatite were investigated. Carbonated apatite was synthesized by a precipitation method and characterized. Batch selenium kinetic and equilibrium experiments were performed. The results indicate the carbonated apatite contained 9.4% carbonate and uptake of selenium as selenite was rapid; 5 hours for complete uptake of selenium vs. more than 100 hours for pure hydroxyapatite reported in the literature. Additionally, the carbonated apatite exhibited significantly higher distribution coefficients in equilibrium experiments than pure apatite under similar experimental conditions. The next phase of this work will be to seek additional funds to continue the research with the goal of eventually demonstrating the technology in a field application.

  2. Genetic polymorphisms that affect selenium status and response to selenium supplementation in United Kingdom pregnant women.

    Science.gov (United States)

    Mao, Jinyuan; Vanderlelie, Jessica J; Perkins, Anthony V; Redman, Christopher W G; Ahmadi, Kourosh R; Rayman, Margaret P

    2016-01-01

    Low selenium status in pregnancy has been associated with a number of adverse conditions. In nonpregnant populations, the selenium status or response to supplementation has been associated with polymorphisms in dimethylglycine dehydrogenase (DMGDH), selenoprotein P (SEPP1) and the glutathione peroxidases [cytosolic glutathione peroxidase (GPx1) and phospholipid glutathione peroxidase (GPx4)]. We hypothesized that, in pregnant women, these candidate polymorphisms would be associated with selenium status in early pregnancy, its longitudinal change, and the interindividual response to selenium supplementation at 60 μg/d. With the use of stored samples and data from the United Kingdom Selenium in Pregnancy Intervention (SPRINT) study in 227 pregnant women, we carried out genetic-association studies, testing for associations between selenium status, its longitudinal change, and response to supplementation and common genetic variation in DMGDH (rs921943), SEPP1 (rs3877899 and rs7579), GPx1 (rs1050450) and GPx4 (rs713041). Selenium status was represented by the concentration of whole-blood selenium at 12 and 35 wk of gestation, the concentration of toenail selenium at 16 wk of gestation, and plasma glutathione peroxidase (GPx3) activity at 12 and 35 wk of gestation. Our results showed that DMGDH rs921943 was significantly associated with the whole-blood selenium concentration at 12 wk of gestation (P = 0.032), which explained ≤2.0% of the variance. This association was replicated with the use of toenail selenium (P = 0.043). In unsupplemented women, SEPP1 rs3877899 was significantly associated with the percentage change in whole-blood selenium from 12 to 35 wk of gestation (P = 0.005), which explained 8% of the variance. In supplemented women, SEPP1 rs3877899 was significantly associated with the percentage change in GPx3 activity from 12 to 35 wk of gestation (P = 0.01), which explained 5.3% of the variance. Selenium status was not associated with GPx1, GPx4, or SEPP1

  3. Characterization of Selenium Species in the Shijimi Clam.

    Science.gov (United States)

    Yoshida, Sakura; Koga, Kaori; Iwataka, Miho; Fuchigami, Takeshi; Haratake, Mamoru; Nakayama, Morio

    2017-01-01

    Selenium is an essential trace element for humans and animals. Fish and shellfish are known to be rich in selenium and suppose to be an effective selenium source. In this study, we characterized the selenium species in the Shijimi clam (Corbicula japonica), which is a typical clam eaten in Japan. The Shijimi clam contains a relatively high concentration of selenium (3.5 µg-selenium/g-dry Shijimi). Approximately 30% of the total selenium in the Shijimi clam meat was extractable with water, while selenium in the Shijimi clam was hardly extracted with ethanol, chloroform and hexane. Based on an ultrafiltration study, the molecular mass of the major selenium species in the Shijimi water-extract was estimated to be less than 5000. Because amphoteric selenium species were contained in the Shijimi water-extract, which was indicated by ion-exchange chromatographic separation, an ion-pair reagent was utilized to extract the ionic selenium species into an organic solvent. A matrix assisted laser desorption ionization (MALDI) time of flight (TOF)-mass spectrometric analysis revealed the selenium isotopic pattern involving one selenium atom in a molecule with the 80Se molecular ion peak at m/z 534. This selenium species was mainly found in the visceral part of the Shijimi clam by imaging mass spectrometry.

  4. Protein expression-yeast.

    Science.gov (United States)

    Nielsen, Klaus H

    2014-01-01

    Yeast is an excellent system for the expression of recombinant eukaryotic proteins. Both endogenous and heterologous proteins can be overexpressed in yeast (Phan et al., 2001; Ton and Rao, 2004). Because yeast is easy to manipulate genetically, a strain can be optimized for the expression of a specific protein. Many eukaryotic proteins contain posttranslational modifications that can be performed in yeast but not in bacterial expression systems. In comparison with mammalian cell culture expression systems, growing yeast is both faster and less expensive, and large-scale cultures can be performed using fermentation. While several different yeast expression systems exist, this chapter focuses on the budding yeast Saccharomyces cerevisiae and will briefly describe some options to consider when selecting vectors and tags to be used for protein expression. Throughout this chapter, the expression and purification of yeast eIF3 is shown as an example alongside a general scheme outline. © 2014 Elsevier Inc. All rights reserved.

  5. Yeast Infection during Pregnancy

    Science.gov (United States)

    ... OK? What's the best way to treat a yeast infection during pregnancy? Answers from Yvonne Butler Tobah, M.D. You can safely treat a yeast infection during pregnancy with various over-the-counter ...

  6. Interaction between vitamin B6 and source of selenium on the response of the selenium-dependent glutathione peroxidase system to oxidative stress induced by oestrus in pubertal pig.

    Science.gov (United States)

    Dalto, Danyel Bueno; Roy, Mélanie; Audet, Isabelle; Palin, Marie-France; Guay, Frédéric; Lapointe, Jérôme; Matte, J Jacques

    2015-10-01

    This study aimed to assess the interaction between vitamin B6 and selenium (Se) for the flow of Se towards the Se-dependent glutathione peroxidase (GPX) system in response to oxidative stress naturally induced by oestrus in a pubertal pig model. At first oestrus, forty-five gilts were randomly assigned to the experimental diets (n=9/group): basal diet (CONT); CONT+0.3mg/kg of Na-selenite (MSeB60); MSeB60+10mg/kg of HCl-B6 (MSeB610); CONT+0.3mg/kg of Se-enriched yeast (OSeB60); and OSeB60+10mg/kg of HCl-B6 (OSeB610). Blood samples were collected at each oestrus (long-term profiles), and daily from day -4 to +3 (slaughter) of the fourth oestrus (peri-oestrus profiles) after which liver, kidneys, and ovaries were collected. For long-term profiles, CONT had lower blood Se than Se-supplemented gilts (p<0.01) and OSe was higher than MSe (p<0.01). Lower erythrocyte pyridoxal-5-phosphate was found in B60 than B610 (p<0.01). No treatment effect was observed on GPX activity. For peri-oestrus profiles, treatment effects were similar to long-term profiles. Treatment effects on liver Se were similar to those for long-term blood Se profiles and OSe had higher renal Se concentrations than MSe gilts (p<0.01). Gene expressions of GPX1, GPX3, GPX4, and selenocysteine lyase in liver and kidney were greatest in OSeB610 gilts (p<0.05). These results suggest that dietary B6 modulate the metabolic pathway of OSe towards the GPX system during the peri-oestrus period in pubertal pigs. Crown Copyright © 2015. Published by Elsevier GmbH. All rights reserved.

  7. Reproductive impacts of elevated selenium levels

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The objectives of this study were to: 1. Evaluate selenium levels in Neotropical migrants and riparian obligate birds on Imperial National Wildlife Refuge. 2....

  8. Selenium nanoparticles: potential in cancer gene and drug delivery.

    Science.gov (United States)

    Maiyo, Fiona; Singh, Moganavelli

    2017-05-01

    In recent decades, colloidal selenium nanoparticles have emerged as exceptional selenium species with reported chemopreventative and therapeutic properties. This has sparked widespread interest in their use as a carrier of therapeutic agents with results displaying synergistic effects of selenium with its therapeutic cargo and improved anticancer activity. Functionalization remains a critical step in selenium nanoparticles' development for application in gene or drug delivery. In this review, we highlight recent developments in the synthesis and functionalization strategies of selenium nanoparticles used in cancer drug and gene delivery systems. We also provide an update of recent preclinical studies utilizing selenium nanoparticles in cancer therapeutics.

  9. Is selenium supplementation in autoimmune thyroid diseases justified?

    DEFF Research Database (Denmark)

    Winther, Kristian H.; Bonnema, Steen; Hegedüs, Laszlo

    2017-01-01

    PURPOSE OF REVIEW: This review provides an appraisal of recent evidence for or against selenium supplementation in patients with autoimmune thyroid diseases, and discusses possible effect mechanisms. RECENT FINDINGS: Epidemiological data suggest an increased prevalence of autoimmune thyroid...... diseases under conditions of low dietary selenium intake. Two systematic reviews have evaluated controlled trials among patients with autoimmune thyroiditis and report that selenium supplementation decreases circulating thyroid autoantibodies. The immunomodulatory effects of selenium might involve reducing...... proinflammatory cytokine release. However, clinically relevant effects of selenium supplementation, including improvement in quality of life, are more elusive. In Graves’ disease, some, but not all, trials indicate that adjuvant selenium supplementation enhances the restoration of biochemical euthyroidism...

  10. Selenium supplementation for patients with Graves’ hyperthyroidism (the GRASS trial)

    DEFF Research Database (Denmark)

    Watt, Torquil; Cramon, Per; Bjorner, Jakob Bue

    2013-01-01

    Graves' hyperthyroidism is an autoimmune disease causing hyperfunction of the thyroid gland. The concentration of selenium is high in the thyroid gland and two important groups of enzymes within the thyroid are selenoproteins, that is, they depend on selenium. Selenium may have beneficial effects...... on autoimmune hypothyroidism and on Graves' orbitopathy, but the effects of selenium on Graves' hyperthyroidism is unknown.We hypothesize that adjuvant selenium may be beneficial in the treatment of Graves' hyperthyroidism. The objective is to investigate if selenium supplementation plus standard treatment......, anti-thyroid drug treatment success), and improved quality of life in patients with Graves' hyperthyroidism....

  11. Selenium deficiency and toxicity in the environment

    OpenAIRE

    Fordyce, Fiona

    2005-01-01

    Selenium (Se) is a naturally occurring metalloid element, which is essential to human and other animal health in trace amounts but is harmful in excess. Of all the elements, selenium has one of the narrowest ranges between dietary deficiency (40 gday1) and toxic levels (400gday1) (WHO, 1996), which makes it necessary to carefully control intakes by humans and other animals, hence, the importance of understanding the relationships between environmental exposure and health. Geology exerts...

  12. Accidental death from acute selenium poisoning.

    Science.gov (United States)

    See, Katharine A; Lavercombe, Peter S; Dillon, Jasmine; Ginsberg, Riesa

    2006-10-02

    We report a fatal case of acute selenium poisoning in a 75-year-old man. After reading on the Internet about a possible role of selenium in prostate cancer, the patient ingested 10 g of sodium selenite. Despite intensive care treatment, he suffered a cardiac arrest and died 6 hours after ingestion. This case illustrates the risks of failing to critically evaluate Internet information and exposes the myth that natural therapies are inherently safe.

  13. Pathology of selenium poisoning in fish

    Science.gov (United States)

    A. Dennis Lemly

    1998-01-01

    Selenium presents an interesting paradox in the field of aquatic toxicology because it is both a nutrient and a poison. As a nutrient, it is required in the diet of fish at concentrations of about 0. 1 to 0. 5 Fg/g dry weight. Selenium is necessary for proper formation and functioning of glutathione peroxidase, which is a major cellular antioxidant enzyme. This enzyme...

  14. The role of selenium in predicting preeclampsia

    Directory of Open Access Journals (Sweden)

    Z Ghaemi

    2013-10-01

    Full Text Available Introduction: Preeclampsia is a common disorder that is a leading cause of perinatal and maternal morbidity and mortality; however its specific etiology has still remained obscure.The first step in preventing preeclampsia is early detection of women at risk. Since there is no valid and reliable screening test, appropriate diagnostic and screening tests are necessary, which are inexpensive, non-invasive and beneficial for pregnant women. Therefore, regarding the role of selenium as an antioxidant in the prevention preeclampsia, this study was designed which aimed to determine the prognostic value of plasma selenium levels in the diagnosis of preeclampsia in primigravida women Methods: In a nested case control design, a sample of 650 normal primigravida women of 24-28 weeks participated in the study. Subjects who involved the case group were followed up for 3 months and 38 were affected by preeclampsia. Blood samples were obtained from these 38patients as well as from 38 subjects as their matched controls. Moreover, the amount of selenium was measured by atomic absorption spectrometry. Results: The mean level of selenium in blood plasma of the cases was significantly lower than in their matched controls. The present study findings revealed that pregnant women with serum Se < 66.1 μg/L had a significantly increased risk of preeclampsia. Conclusion: Lower plasma selenium level in women destines to suffering from preeclampsia which confirms the destructive effect of selenium deficiency as an antioxidant in etiopathology of preeclampsia. Measurement of plasma selenium can improve the prediction of preeclampsia; thus, it seems that plasma selenium level test owns an acceptable sensitivity and specificity for predicting preeclampsia.

  15. Selenium in human health and disease.

    Science.gov (United States)

    Fairweather-Tait, Susan J; Bao, Yongping; Broadley, Martin R; Collings, Rachel; Ford, Dianne; Hesketh, John E; Hurst, Rachel

    2011-04-01

    This review covers current knowledge of selenium in the environment, dietary intakes, metabolism and status, functions in the body, thyroid hormone metabolism, antioxidant defense systems and oxidative metabolism, and the immune system. Selenium toxicity and links between deficiency and Keshan disease and Kashin-Beck disease are described. The relationships between selenium intake/status and various health outcomes, in particular gastrointestinal and prostate cancer, cardiovascular disease, diabetes, and male fertility, are reviewed, and recent developments in genetics of selenoproteins are outlined. The rationale behind current dietary reference intakes of selenium is explained, and examples of differences between countries and/or expert bodies are given. Throughout the review, gaps in knowledge and research requirements are identified. More research is needed to improve our understanding of selenium metabolism and requirements for optimal health. Functions of the majority of the selenoproteins await characterization, the mechanism of absorption has yet to be identified, measures of status need to be developed, and effects of genotype on metabolism require further investigation. The relationships between selenium intake/status and health, or risk of disease, are complex but require elucidation to inform clinical practice, to refine dietary recommendations, and to develop effective public health policies.

  16. Biological activity of selenium: Revisited.

    Science.gov (United States)

    Wrobel, Jagoda K; Power, Ronan; Toborek, Michal

    2016-02-01

    Selenium (Se) is an essential micronutrient that exerts multiple and complex effects on human health. Se is essential for human well-being largely due to its potent antioxidant, anti-inflammatory, and antiviral properties. The physiological functions of Se are carried out by selenoproteins, in which Se is specifically incorporated as the amino acid, selenocysteine. Importantly, both beneficial and toxic effects of Se have been reported suggesting that the mode of action of Se is strictly chemical form and concentration dependent. Additionally, there is a relatively narrow window between Se deficiency and toxicity and growing evidence suggests that Se health effects depend greatly on the baseline level of this micronutrient. Thus, Se supplementation is not an easy task and requires an individualized approach. It is essential that we continue to explore and better characterize Se containing compounds and mechanisms of action, which could be crucial for disease prevention and treatment. © 2015 International Union of Biochemistry and Molecular Biology.

  17. Thin film solar cells by selenization sulfurization using diethyl selenium as a selenium precursor

    Science.gov (United States)

    Dhere, Neelkanth G.; Kadam, Ankur A.

    2009-12-15

    A method of forming a CIGSS absorber layer includes the steps of providing a metal precursor, and selenizing the metal precursor using diethyl selenium to form a selenized metal precursor layer (CIGSS absorber layer). A high efficiency solar cell includes a CIGSS absorber layer formed by a process including selenizing a metal precursor using diethyl selenium to form the CIGSS absorber layer.

  18. [Selenium levels in human bodies and environment in Qinghai province].

    Science.gov (United States)

    Shu, S; Yuan, J; Yan, H

    1996-07-01

    To study selenium level, its distribution in human bodies and environment and its effects on health, 3,035 specimens of human hair, blood, urine, and environmetal water, soil, food were collected from 91 sampling spots in 23 cities and counties of Qinghai Province and determined for selenium levels with fluorescence analysis. Results showed overall biological selenium level of human bodies in Qinghai Province was low and blood selenium level was lower than the normal reference value in 84.73% of the population, same as that in selenium-poor nations. Environmental selenium was poor or in a deficient status in Qinghai Province, 69.57% of the areas in the Province was in low, poor, or severely deficient selenium. Selenium level in vegetable food correlated closely with that in human blood, which indicated low selenium level in environment caused human selenium deficient in their internal environment via food chain. There were difference in biological selenium levels of human bodies in seven districts and six ethnic nationalities, which suggests selenium levels in human bodies correlate closely with economic development, selenium intake, geographical environment, living habits and customs, etc., and are nothing to do with the altitude above sea level.

  19. Effect of Selenium and Vitamin E Supplementation on Semen Quality in Dogs with Lowered Fertility

    Directory of Open Access Journals (Sweden)

    Domosławska Anna

    2015-04-01

    Full Text Available Thirty clinically healthy dogs with poor semen quality were used in the study. Fifteen dogs were supplemented daily with selenium (0.6 mg/kg organic selenium from yeast and vitamin E (5 mg/kg per os for 60 d. The control group (15 dogs was not supplemented. Semen was collected from all dogs by manual manipulation on days 0, 30, 60, and 90. The sperm concentration and motility parameters were evaluated with a Hamilton Thorne sperm analyser, version IVOS 12.3. For the assessment of sperm morphology, Diff-Quik stain was used. The percentage of live and dead spermatozoa was estimated on dried smears stained with eosin-nigrosin. The concentration of spermatozoa, most motility parameters determined (PMOT, VSL, VCL, ALH, BCF, RAPID, MEDIUM, SLOW, and STATIC, and the percentage of spermatozoa morphologically normal and live increased significantly (P < 0.05 after 60 d of supplementation. In the control group, there were no changes in motility parameters while the concentration and total sperm count decreased over the duration of the study. In conclusion, supplementation with selenium and vitamin E for 60 d can improve the quality of semen in dogs with lowered fertility.

  20. Quantitative determination of selenium metabolites in human urine by LC-DRC-ICP-MS

    DEFF Research Database (Denmark)

    Gammelgaard, Bente; Bendahl, L.; Jacobsen, N.W.

    2005-01-01

    Two selenium metabolites, Se-methylseleno-N-acetylgalactosamine (SeGal-N-Ac) and Se-methyl-selenogalactosamine (SeGal-NH2), were quantified in human urine by LC-DRC-ICP-MS. Urine samples were analysed after 1+1 dilution in a reversed phase chromatographic system using an eluent consisting of 200 m......M ammonium acetate and 5% methanol with a pH of 9.25 and quantified by standard addition. Samples were collected from 8 volunteers before and after 5 days ingestion of 100 mu g Se day(-1) in form of selenized yeast. The average concentration of (SeGal-NH2) before and after selenium intake was 1.4 and 1.9 mu...... g Se L-1, respectively, while the average concentration of Se-Gal-N-Ac increased from 2.6 to 11.6 mu g Se L-1 before and after selenium consumption. Detection limits calculated on basis of three times the standard deviation on peak areas of 2 mu g Se L-1 solutions were 0.1 mu g Se L-1 for SeGal-NH2...

  1. Organic selenium supplementation increased selenium concentrations in ewe and newborn lamb blood and in slaughter lamb meat compared to inorganic selenium supplementation

    OpenAIRE

    Steen Arvid; Strøm Turid; Bernhoft Aksel

    2008-01-01

    Abstract Background Selenium is part of the antioxidant defence system in animals and humans. The available selenium concentration in soil is low in many regions of the world. The purpose of this study was to evaluate the effect of organic versus inorganic selenium supplementation on selenium status of ewes, their lambs, and slaughter lambs. Methods Ewes on four organic farms were allocated five or six to 18 pens. The ewes were given either 20 mg/kg inorganic selenium as sodium selenite or or...

  2. Yeast for virus research

    Science.gov (United States)

    Zhao, Richard Yuqi

    2017-01-01

    Budding yeast (Saccharomyces cerevisiae) and fission yeast (Schizosaccharomyces pombe) are two popular model organisms for virus research. They are natural hosts for viruses as they carry their own indigenous viruses. Both yeasts have been used for studies of plant, animal and human viruses. Many positive sense (+) RNA viruses and some DNA viruses replicate with various levels in yeasts, thus allowing study of those viral activities during viral life cycle. Yeasts are single cell eukaryotic organisms. Hence, many of the fundamental cellular functions such as cell cycle regulation or programed cell death are highly conserved from yeasts to higher eukaryotes. Therefore, they are particularly suited to study the impact of those viral activities on related cellular activities during virus-host interactions. Yeasts present many unique advantages in virus research over high eukaryotes. Yeast cells are easy to maintain in the laboratory with relative short doubling time. They are non-biohazardous, genetically amendable with small genomes that permit genome-wide analysis of virologic and cellular functions. In this review, similarities and differences of these two yeasts are described. Studies of virologic activities such as viral translation, viral replication and genome-wide study of virus-cell interactions in yeasts are highlighted. Impacts of viral proteins on basic cellular functions such as cell cycle regulation and programed cell death are discussed. Potential applications of using yeasts as hosts to carry out functional analysis of small viral genome and to develop high throughput drug screening platform for the discovery of antiviral drugs are presented. PMID:29082230

  3. Study of trace elements remobilization from a contaminated soil: influence of soil organic compounds ageing on the selenium remobilization; Etude de la remobilisation d'elements traces a partir d'un sol de surface contamine: influence du vieillissement de la matiere organique du sol sur la remobilisation du selenium

    Energy Technology Data Exchange (ETDEWEB)

    Chabroullet, Ch

    2007-03-15

    {sup 79}Se is a high-life fission product presents in high-activity nuclear wastes. Selenium is often taking into account for health and environmental risk assessments as it is usually considered as a mobile and a toxic element. The terrestrial ecosystems are thought to be a potential reservoir of selenium. In this study, we specially studied how the associations between selenium and soil organic matter and/or microorganisms modify soils selenium mobility and partition (solid, liquid and gaseous). A particular attention was paid to the temporal evolution of the retention parameters, which remains one of the weak points of modeling especially for long term simulations (several tens-hundreds of thousand years). Methodology developed consists on a regular characterization of 3 soils samples pre-contaminated at a very week selenium concentration (2.2*10{sup -9} g Se.g{sup -1} soil) and incubated during 1.5 year in controlled conditions. The evolution of the organic status of the soil samples was established and well modeled (Roth C.). Alternatively, the selenium-OM associations did not present any significant modification with time affecting selenium mobility. The detailed study of selenium mobility showed that selenium sorption processes was poorly reversible (sorption Kd: 20-50 L.kg{sup -1}; desorption Kd: 100-500 L.kg{sup -1}), whatever the soil organic status. In addition, numerous transitory phenomenons were able to disturb the 'basic' behavior of selenium by increasing the amount of soluble selenium. We specially established that: (i) the use of phosphate fertilizers constituted the most important way of selenium remobilization leading to the release of 30-40 % of sorbed selenium in some extreme cases; (ii) the week selenium volatilization ({approx} 0.2 % for 1.5 year of incubation) may constitute a significant biotic way of {sup 79}Se dispersion as soon as very long time scales are considered; (iii) the colloidal transport due to the soil

  4. Selenium Toxicity from a Misformulated Dietary Supplement, Adverse Health Effects, and the Temporal Response in the Nail Biologic Monitor

    Directory of Open Access Journals (Sweden)

    Stacy B. Crane

    2013-03-01

    Full Text Available Use of dietary supplements in the U.S. has increased steadily over the last 25 years. While misformulation is uncommon, the consequences can be serious. A March 2008 voluntary market recall removed supplement products responsible for the most serious selenium toxicity outbreak that has occurred in the U.S. We quantified selenium concentrations in the misformulated supplement products, measured the temporal response in the nail biologic monitor, and associated exposure to self-reported selenosis symptoms. Subjects recruited through state health departments and referrals provided samples of the misformulated supplement products, exposure information, monthly toenail and or fingernail clippings or onycholysitic nail fragments, and listed their newly onset adverse health effects attributed to selenium toxicity. Ninety-seven subjects enrolled and submitted at least one test sample. Peak selenium concentrations (up to 18.3 and 44.1 μg/g for toenails and fingernails, respectively were measured. Multiple samples (52 total of all six recalled supplement lots were analyzed ranging from 22,300 to 32,200 μg selenium per daily dose. Average consumption was 30.9 ± 13.9 doses; 73 subjects provided follow-up data on selenosis symptoms at 2.50 ± 0.14 years. Nail samples accurately reflect exposure in this selenium toxicity outbreak, which resulted in long-term/permanent adverse health effects.

  5. Selenium toxicity from a misformulated dietary supplement, adverse health effects, and the temporal response in the nail biologic monitor.

    Science.gov (United States)

    Morris, John Steven; Crane, Stacy B

    2013-03-28

    Use of dietary supplements in the U.S. has increased steadily over the last 25 years. While misformulation is uncommon, the consequences can be serious. A March 2008 voluntary market recall removed supplement products responsible for the most serious selenium toxicity outbreak that has occurred in the U.S. We quantified selenium concentrations in the misformulated supplement products, measured the temporal response in the nail biologic monitor, and associated exposure to self-reported selenosis symptoms. Subjects recruited through state health departments and referrals provided samples of the misformulated supplement products, exposure information, monthly toenail and or fingernail clippings or onycholysitic nail fragments, and listed their newly onset adverse health effects attributed to selenium toxicity. Ninety-seven subjects enrolled and submitted at least one test sample. Peak selenium concentrations (up to 18.3 and 44.1 μg/g for toenails and fingernails, respectively) were measured. Multiple samples (52 total) of all six recalled supplement lots were analyzed ranging from 22,300 to 32,200 μg selenium per daily dose. Average consumption was 30.9 ± 13.9 doses; 73 subjects provided follow-up data on selenosis symptoms at 2.50 ± 0.14 years. Nail samples accurately reflect exposure in this selenium toxicity outbreak, which resulted in long-term/permanent adverse health effects.

  6. EURRECA-Estimating selenium requirements for deriving dietary reference values.

    Science.gov (United States)

    Hurst, Rachel; Collings, Rachel; Harvey, Linda J; King, Maria; Hooper, Lee; Bouwman, Jildau; Gurinovic, Mirjana; Fairweather-Tait, Susan J

    2013-01-01

    Current reference values for selenium, an essential micronutrient, are based on the intake of selenium that is required to achieve maximal glutathione peroxidase activity in plasma or erythrocytes. In order to assess the evidence of relevance to setting dietary reference values for selenium, the EURRECA Network of Excellence focused on systematic searches, review, and evaluation of (i) selenium status biomarkers and evidence for relationships between intake and status biomarkers, (ii) selenium and health (including the effect of intake and/or status biomarkers on cancer risk, immune function, HIV, cognition, and fertility), (iii) bioavailability of selenium from the diet, and (iv) impact of genotype/single nucleotide polymorphisms on status or health outcomes associated with selenium. The main research outputs for selenium and future research priorities are discussed further in this review.

  7. Optimization of selenoprotein P and other plasma selenium biomarkers for the assessment of the selenium nutritional requirement: a placebo-controlled, double-blind study of selenomethionine supplementation in selenium-deficient Chinese subjects1234

    OpenAIRE

    Xia, YiMing; Hill, Kristina E.; Li, Ping; Xu, Jiayuan; Zhou, Dingyou; Motley, Amy K.; WANG, LI; Byrne, Daniel W.; Burk, Raymond F.

    2010-01-01

    Background: The intake of selenium needed for optimal health has not been established. Selenoproteins perform the functions of selenium, and the selenium intake needed for their full expression is not known.

  8. Effect of pulsed electric fields (PEF) on accumulation of selenium and zinc ions in Saccharomyces cerevisiae cells.

    Science.gov (United States)

    Pankiewicz, Urszula; Sujka, Monika; Kowalski, Radosław; Mazurek, Artur; Włodarczyk-Stasiak, Marzena; Jamroz, Jerzy

    2017-04-15

    The cultures of Saccharomyces cerevisiae were treated with pulsed electric fields (PEF) in order to obtain a maximum accumulation of selenium and zinc ions (simultaneously) in the biomass. The following concentrations: 100μgSe/ml and 150μgZn/ml medium were assumed to be optimal for the maximum accumulation of these ions, that is 43.07mg/gd.m. for selenium and 14.48mg/gd.m. for zinc, in the cultures treated with PEF. At optimal PEF parameters: electric field strength of 3kV/cm and pulse width of 10μs after the treatment of 20-h culture for 10min, the maximum accumulation of both ions in the yeast cells was observed. Application of PEF caused the increase of ions accumulation by 65% for selenium and 100% for zinc. Optimization of PEF parameters led to the further rise in the both ions accumulation resulting in over 2-fold and 2.5-fold higher concentration of selenium and zinc. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Effects of Lead+Selenium Interaction on Acetylcholinesterase Activity in Brain and Accumulation of Metal in Tissues of Oreochromis niloticus (L., 1758

    Directory of Open Access Journals (Sweden)

    Gülsemin Şen

    2017-06-01

    Full Text Available The potential accumulation of lead in different tissues of Oreochromis niloticus and the effects of selenium in AChE inhibition caused by lead in brain were investigated. Juvenile O. niloticus samples were exposed to combination of 1 mg L-1 and 2 mg L-1 lead and 1mg L-1 lead+2mg L-1 selenium and 2mg L-1 lead+4mg L-1 selenium for 1, 7 and 15 days respectively. The accumulation of lead in gill, brain, liver and muscle tissues was analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS as well as brain acetylcholinesterase (AChE, E.C.3.1.1.7 enzyme activity was also analyzed by spectrophotometric method. No mortality was observed during lead exposure in relation to time period and exposed concentrations. Lead accumulation was occurred in all tissues in relation to time. Maximum lead accumulation occurred in brain tissue, followed by the liver, gills and muscle tissues in relation to time period. Selenium caused decrease accumulation of lead in tissues (all selenium mixtures in muscle tissue on the first day, 1mg L-1 Pb+2mg L-1 selenium in gill tissue on the seventh day, in liver tissue on the seventh day except 2mg L-1 Pb+4mg L-1 selenium mixtures at the end of each of all three test periods. Inhibition of AChE activity was caused by the highest concentration and by the short-term effect of lead. Such effect of lead was eliminated by selenium mixture. Lead and selenium mixture were resulted an increase in activity on 15th day at the highest concentration. Selenium led to decrease in the accumulation of lead in the tissues and caused to improvement in the loss of AChE activity.

  10. Updates on clinical studies of selenium supplementation in radiotherapy

    OpenAIRE

    Puspitasari, Irma M.; Abdulah, Rizky; Yamazaki, Chiho; KAMEO, Satomi; Nakano, Takashi; Koyama, Hiroshi

    2014-01-01

    To establish guidelines for the selenium supplementation in radiotherapy we assessed the benefits and risks of selenium supplementation in radiotherapy. Clinical studies on the use of selenium in radiotherapy were searched in the PubMed electronic database in January 2013. Sixteen clinical studies were identified among the 167 articles selected in the initial search. Ten articles were observational studies, and the other 6 articles reported studies on the effects of selenium supplementation i...

  11. Selenium nanoparticle-enriched biomass of Yarrowia lipolytica enhances growth and survival of Artemia salina.

    Science.gov (United States)

    Hamza, Faseela; Vaidya, Amogh; Apte, Mugdha; Kumar, Ameeta Ravi; Zinjarde, Smita

    2017-11-01

    Controlling disease outbreaks is a major challenge in aquaculture farms and conventional methods are often ineffective. Nutritional supplementation and probiotic preparations help in reducing severity of such infections. The generally regarded as safe yeast (Yarrowia lipolytica) was used in the current study. A marine strain of Y. lipolytica exhibited tolerance towards sodium selenite and formed cell associated selenium nanoparticles (SeNPs). The synthesized nanoparticles were characterized by UV-vis spectroscopy, X-ray diffraction (XRD) and Field Emission Scanning Electron Microscope (FE-SEM) observations. Fourier transform infra-red (FTIR) spectroscopy indicated the role of carboxylic and amine groups in the synthesis of nanoparticles. This SeNP-enriched biomass was used as feed for the model aquaculture system, Artemia salina and compared with normal feed, baker's yeast (Saccharomyces cerevisiae). A. salina fed with SeNP-enriched biomass, showed increased survival rates (96.66%) as compared to those fed with S. cerevisiae (60.0%). The size of the larvae fed with SeNP-enriched biomass of Y. lipolytica was also found to be larger. Additionally, larval groups fed with SeNP-enriched biomass were better protected (70.0% survival) against V. harveyi infection when compared with groups fed with S. cerevisiae (24.44%). This combination of selenium in the nanoparticle form associated with the biomass of Y. lipolytica has potential application in improving health of aquaculture species in farms. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Effects of selenium supplementation on the oxidative state of acute heat stress-exposed quails.

    Science.gov (United States)

    Del Vesco, A P; Gasparino, E; Zancanela, V; Grieser, D O; Stanquevis, C E; Pozza, P C; Oliveira Neto, A R

    2017-02-01

    This study aimed to evaluate the effect of heat stress (HS) and selenium supplementation on markers of stress, meat quality and gene expression. For this, meat quails of 42 days of age were fed a diet that either met [0.33 mg/kg, nutritional demand for selenium (SS)] or did not meet [0.11 mg/kg, selenium deficient (SD)] the nutritional demands for selenium during the 7 days of evaluation. In addition, the animals were kept at either a thermal comfort temperature (25 °C) or exposed to HS (38 °C for 24 h). Glutathione synthetase (GSS), glutathione reductase (GSR) and uncoupling protein (UCP) gene expression were influenced by the interaction between temperature and diet. Animals subjected to HS and fed the SS diet exhibited the highest GSS and GSR gene expression. In terms of UCP gene expression, the lowest values were observed in HS animals on the SD diet. Glutathione peroxidase 7 (GPX7) gene expression, body temperature (BT) and creatine kinase (CK) activity were influenced by both selenium supplementation and HS. Aspartate aminotransferase (AST), alanine aminotransferase (ALT) activity and creatinine content all were influenced by the diet/environment interaction. The highest AST activity, ALT activity and creatinine levels were observed in animals that were both on the SD diet and exposed to HS. HS animals also exhibited an increased heterophil/lymphocyte ratio and lower triiodothyronine (T3) hormone levels than birds that remained at the comfortable temperature. Animals subjected to HS and fed with selenium supplemented diet showed better results regarding gene expression and, thus, better results for the activities of enzymes used as stress markers, which could be due to the higher antioxidant capacity provided by the action of the studied genes. Journal of Animal Physiology and Animal Nutrition © 2016 Blackwell Verlag GmbH.

  13. Low blood selenium: A probable factor in essential hypertension ...

    African Journals Online (AJOL)

    The possible association between selenium and essential hypertension was investigated in this study. Blood selenium (BSe) and plasma glutathione peroxidase (plGSH-Px) activity were measured as biochemical markers of selenium status of 103 hypertensive patients (44 males and 59 females) and 88 apparently healthy ...

  14. Reduced Maternal Selenium levels in Pregnant and Lactating ...

    African Journals Online (AJOL)

    Reduced Maternal Selenium levels in Pregnant and Lactating Nigerian women: Should Routine Selenium Supplementation be advocated? ... However, there was a non significant increase immediately after birth. In the breast milk, selenium concentration significantly decreased (P<0.0001) as lactation progressed.

  15. Bio-induced solid selenium for recovery from water

    NARCIS (Netherlands)

    Hageman, S.P.W.

    2015-01-01

    Selenium in the form of selenate or selenite in wastewater needs to be removed due to its potential toxicity in the environment. Also, selenium is a valuable element that is used in several industries and current selenium resources are likely to be exhausted in less than 50 years. Waste streams

  16. Selenium deficiency and the effects of supplementation on preterm infants

    Science.gov (United States)

    Freitas, Renata Germano B. O. N.; Nogueira, Roberto José N.; Antonio, Maria Ângela R. G. M.; Barros-Filho, Antonio de Azevedo; Hessel, Gabriel

    2014-01-01

    Objective: This study aimed to review the literature about blood concentrations of selenium associated with gestational age, feeding, supplementation and related clinical features in preterm infants. Data sources: Systematic review in the following databases: MEDLINE, PubMed, Google academics, SciELO. org, ScienceDirect (Elsevier) and CINAHL-Plus with Full Text (EBSCO). Articles published up to January 2013 with the keywords "selenium deficiency", "selenium supplementation", "neonates", "infants", "newborn" and "preterm infants" were selected. Data synthesis: The studies reported that low blood selenium levels are associated with increased risk of respiratory diseases. Preterm infants, especially with low birth weight, presented lower selenium levels. Selenium deficiency has also been associated with the use of oral infant formula, enteral and parenteral nutrition (with or without selenium addition). The optimal dose and length of selenium supplementation is not well-established, since they are based only on age group and selenium ingestion by breastfed children. Furthermore, the clinical status of the infant affected by conditions that may increase oxidative stress, and consequently, selenium requirements is not taken into account. Conclusions: Prematurity and low birth weight can contribute to low blood selenium in premature infants. Selenium supplementation seems to minimize or prevent clinical complications caused by prematurity. PMID:24676200

  17. Evaluation Of Selenium Supplementation Alone, A Combination Of ...

    African Journals Online (AJOL)

    The effect of selenium supplementation alone and a combination of selenium and Vitamin E or low dose diminazene aceturate (berenil) was investigated in Trypanosoma brucei brucei infected rats. The effect of the selenium supplementation and its combinations were assessed using the parasitaemia, changes in body ...

  18. NAIL KERATIN AS MONITOR-TISSUE FOR SELENIUM EXPOSURE

    NARCIS (Netherlands)

    VANNOORD, PAH; MAAS, MJ; DEBRUIN, M

    1992-01-01

    Nail clippings might provide a way to monitor exposure to selenium in the recent past of an individual, since a clipping collected from a toe would reflect exposures months before actual clipping date. The relation between levels of exogenous selenium exposure and selenium levels in nail keratin was

  19. Environmental Selenium Research: From Microscopic Processes to Global Understanding

    NARCIS (Netherlands)

    Winkel, L.H.E.; Johnson, C.A.; Lenz, M.; Grundl, T.; Leupin, O.X.; Amini, M.; Charlet, L.

    2012-01-01

    Selenium is a natural trace element that is of fundamental importance to human health. The extreme geographical variation in selenium concentrations in soils and food crops has resulted in significant health problems related to deficient or excess levels of selenium in the environment. To deal with

  20. Selenistasis: Epistatic Effects of Selenium on Cardiovascular Phenotype

    Science.gov (United States)

    Joseph, Jacob; Loscalzo, Joseph

    2013-01-01

    Although selenium metabolism is intricately linked to cardiovascular biology and function, and deficiency of selenium is associated with cardiac pathology, utilization of selenium in the prevention and treatment of cardiovascular disease remains an elusive goal. From a reductionist standpoint, the major function of selenium in vivo is antioxidant defense via its incorporation as selenocysteine into enzyme families such as glutathione peroxidases and thioredoxin reductases. In addition, selenium compounds are heterogeneous and have complex metabolic fates resulting in effects that are not entirely dependent on selenoprotein expression. This complex biology of selenium in vivo may underlie the fact that beneficial effects of selenium supplementation demonstrated in preclinical studies using models of oxidant stress-induced cardiovascular dysfunction, such as ischemia-reperfusion injury and myocardial infarction, have not been consistently observed in clinical trials. In fact, recent studies have yielded data that suggest that unselective supplementation of selenium may, indeed, be harmful. Interesting biologic actions of selenium are its simultaneous effects on redox balance and methylation status, a combination that may influence gene expression. These combined actions may explain some of the biphasic effects seen with low and high doses of selenium, the potentially harmful effects seen in normal individuals, and the beneficial effects noted in preclinical studies of disease. Given the complexity of selenium biology, systems biology approaches may be necessary to reach the goal of optimization of selenium status to promote health and prevent disease. PMID:23434902

  1. Selenium deficiency and the effects of supplementation on preterm infants.

    Science.gov (United States)

    Freitas, Renata Germano B O N; Nogueira, Roberto Jose N; Antonio, Maria Angela R G M; Barros-Filho, Antonio de Azevedo; Hessel, Gabriel

    2014-03-01

    This study aimed to review the literature about blood concentrations of selenium associated with gestational age, feeding, supplementation and related clinical features in preterm infants. Systematic review in the following databases: MEDLINE, PubMed, Google academics, SciELO. org, ScienceDirect (Elsevier) and CINAHL-Plus with Full Text (EBSCO). Articles published up to January 2013 with the keywords "selenium deficiency", "selenium supplementation", "neonates", "infants", "newborn" and "preterm infants" were selected. The studies reported that low blood selenium levels are associated with increased risk of respiratory diseases. Preterm infants, especially with low birth weight, presented lower selenium levels. Selenium deficiency has also been associated with the use of oral infant formula, enteral and parenteral nutrition (with or without selenium addition). The optimal dose and length of selenium supplementation is not well-established, since they are based only on age group and selenium ingestion by breastfed children. Furthermore, the clinical status of the infant affected by conditions that may increase oxidative stress, and consequently, selenium requirements is not taken into account. Prematurity and low birth weight can contribute to low blood selenium in premature infants. Selenium supplementation seems to minimize or prevent clinical complications caused by prematurity.

  2. Selenistasis: epistatic effects of selenium on cardiovascular phenotype.

    Science.gov (United States)

    Joseph, Jacob; Loscalzo, Joseph

    2013-01-31

    Although selenium metabolism is intricately linked to cardiovascular biology and function, and deficiency of selenium is associated with cardiac pathology, utilization of selenium in the prevention and treatment of cardiovascular disease remains an elusive goal. From a reductionist standpoint, the major function of selenium in vivo is antioxidant defense via its incorporation as selenocysteine into enzyme families such as glutathione peroxidases and thioredoxin reductases. In addition, selenium compounds are heterogeneous and have complex metabolic fates resulting in effects that are not entirely dependent on selenoprotein expression. This complex biology of selenium in vivo may underlie the fact that beneficial effects of selenium supplementation demonstrated in preclinical studies using models of oxidant stress-induced cardiovascular dysfunction, such as ischemia-reperfusion injury and myocardial infarction, have not been consistently observed in clinical trials. In fact, recent studies have yielded data that suggest that unselective supplementation of selenium may, indeed, be harmful. Interesting biologic actions of selenium are its simultaneous effects on redox balance and methylation status, a combination that may influence gene expression. These combined actions may explain some of the biphasic effects seen with low and high doses of selenium, the potentially harmful effects seen in normal individuals, and the beneficial effects noted in preclinical studies of disease. Given the complexity of selenium biology, systems biology approaches may be necessary to reach the goal of optimization of selenium status to promote health and prevent disease.

  3. EURRECA—Estimating Selenium Requirements for Deriving Dietary Reference Values

    NARCIS (Netherlands)

    Hurst, R.; Collings, R.; Harvey, L.J.; King, M.; Hooper, L.; Bouwman, J.; Gurinovic, M.; Fairweather-Tait, S.J.

    2013-01-01

    Current reference values for selenium, an essential micronutrient, are based on the intake of selenium that is required to achieve maximal glutathione peroxidase activity in plasma or erythrocytes. In order to assess the evidence of relevance to setting dietary reference values for selenium, the

  4. Selenium deficiency and the effects of supplementation on preterm infants

    Directory of Open Access Journals (Sweden)

    Renata Germano B. O. N. Freitas

    2014-03-01

    Full Text Available Objective: This study aimed to review the literature about blood concentrations of selenium associated with gestational age, feeding, supplementation and related clinical features in preterm infants. Data sources: Systematic review in the following databases: MEDLINE, PubMed, Google academics, SciELO. org, ScienceDirect (Elsevier and CINAHL-Plus with Full Text (EBSCO. Articles published up to January 2013 with the keywords "selenium deficiency", "selenium supplementation", "neonates", "infants", "newborn" and "preterm infants" were selected. Data synthesis: The studies reported that low blood selenium levels are associated with increased risk of respiratory diseases. Preterm infants, especially with low birth weight, presented lower selenium levels. Selenium deficiency has also been associated with the use of oral infant formula, enteral and parenteral nutrition (with or without selenium addition. The optimal dose and length of selenium supplementation is not well-established, since they are based only on age group and selenium ingestion by breastfed children. Furthermore, the clinical status of the infant affected by conditions that may increase oxidative stress, and consequently, selenium requirements is not taken into account. Conclusions: Prematurity and low birth weight can contribute to low blood selenium in premature infants. Selenium supplementation seems to minimize or prevent clinical complications caused by prematurity.

  5. Selenistasis: Epistatic Effects of Selenium on Cardiovascular Phenotype

    Directory of Open Access Journals (Sweden)

    Joseph Loscalzo

    2013-01-01

    Full Text Available Although selenium metabolism is intricately linked to cardiovascular biology and function, and deficiency of selenium is associated with cardiac pathology, utilization of selenium in the prevention and treatment of cardiovascular disease remains an elusive goal. From a reductionist standpoint, the major function of selenium in vivo is antioxidant defense via its incorporation as selenocysteine into enzyme families such as glutathione peroxidases and thioredoxin reductases. In addition, selenium compounds are heterogeneous and have complex metabolic fates resulting in effects that are not entirely dependent on selenoprotein expression. This complex biology of selenium in vivo may underlie the fact that beneficial effects of selenium supplementation demonstrated in preclinical studies using models of oxidant stress-induced cardiovascular dysfunction, such as ischemia-reperfusion injury and myocardial infarction, have not been consistently observed in clinical trials. In fact, recent studies have yielded data that suggest that unselective supplementation of selenium may, indeed, be harmful. Interesting biologic actions of selenium are its simultaneous effects on redox balance and methylation status, a combination that may influence gene expression. These combined actions may explain some of the biphasic effects seen with low and high doses of selenium, the potentially harmful effects seen in normal individuals, and the beneficial effects noted in preclinical studies of disease. Given the complexity of selenium biology, systems biology approaches may be necessary to reach the goal of optimization of selenium status to promote health and prevent disease.

  6. Toxicity of organic and inorganic selenium to mallard ducklings

    Science.gov (United States)

    Heinz, G.H.; Hoffman, D.J.; Gold, L.G.

    1988-01-01

    The toxicity of selenomethionine and sodium selenite to mallard ducklings (Anas platyrhynchos) was measured by feeding each form from hatching to six weeks of age at dietary concentrations of 0, 10, 20, 40, and 80 ppm selenium. At 80 ppm selenium, sodium selenite caused 97.5% mortality by six weeks and selenomethionine caused 100% mortality. At 40 ppm, these two forms of selenium caused 25 and 12.5% mortality. No mortality occurred at 10 or 20 ppm. Diets containing 20, 40, or 80 ppm selenium in both forms caused decreases in food consumption and growth. The only statistically significant effect of 10 ppm selenium was with sodium selenite, which resulted in larger livers than controls. Selenomethionine was more readily stored in the liver than sodium selenite at levels above 10 ppm selenium in the diet. Based on comparisons of residues of selenium in livers of surviving and dead ducklings, concentrations in the liver were not diagnostic of death due to selenium poisoning. Because both forms of selenium resulted in severe reductions in food consumption, selenium-induced starvation may have been related to duckling mortality. It was not clear whether either form of selenium at 10 ppm in the diet resulted in a leveling off of selenium concentrations in the liver within six weeks.

  7. Selenium supplementation in radiotherapy patients: do we need to measure selenium levels in serum or blood regularly prior radiotherapy?

    OpenAIRE

    Mücke, Ralph; Micke, Oliver; Schomburg, Lutz; Kisters, Klaus; Büntzel, Jens; Hübner, Jutta; Kriz, Jan

    2014-01-01

    Considering the review by Puspitasari and colleagues, an additional discussion of the endpoints of the Se supplementation studies described would be helpful. In our view, selenium can safely be given to selenium-deficient cancer patients prior to and during radiotherapy. Therefore, in order to help the radiation oncologist in decision making, we strongly advocate to determine the selenium status prior to and during a potential adjuvant selenium supplementation, e.g. when trying to ease the si...

  8. Selenium and Vitamin E for Prostate Cancer: Post-SELECT (Selenium and Vitamin E Cancer Prevention Trial) Status

    OpenAIRE

    Ledesma, Mark C; Jung-Hynes, Brittney; Schmit, Travis L; Kumar,Raj; Mukhtar, Hasan; Ahmad, Nihal

    2010-01-01

    Various formulations of selenium and vitamin E, both essential human dietary components, have been shown to possess a therapeutic and preventive effect against prostate cancer. Fortuitous results of clinical trials also implied a risk-reduction effect of selenium and vitamin E supplements. The Selenium and Vitamin E Cancer Prevention Trial (SELECT), using oral selenium and vitamin E supplementation in disease-free volunteers, was designed to test a prostate cancer chemoprevention hypothesis. ...

  9. Toenail mercury and dyslipidemia: Interaction with selenium.

    Science.gov (United States)

    Park, Kyong; Seo, Eunmin

    2017-01-01

    Although compelling evidences from in vivo and in vitro studies exist, limited studies have examined the association between chronic mercury exposure and dyslipidemia. Particularly, data are sparse regarding the influence of selenium on this association of mercury with dyslipidemia in humans. The purpose of the current study was to examine the associations of toenail mercury with dyslipidemia and its components, and to examine whether selenium in toenails modifies these associations. We performed cross-sectional analyses using baseline data from a cohort in the Yeungnam area in South Korea, including 232 men and 269 women. Toenail mercury and selenium concentrations were quantified using neutron activation analysis, and fasting serum lipid measurements were obtained through the medical examination. Odds ratios of the prevalent hypercholesterolemia, hyper-LDL-cholesterolemia, hypo-HDL-cholesterolemia, hypertriglyceridemia, and dyslipidemia in correlation with mercury levels were calculated using multivariable logistic regression. The mean levels of toenail mercury were 0.47μg/g for men and 0.34μg/g for women. After adjustment for multiple confounding variables, participants in the highest tertile of toenail mercury levels had 4.08 (95% CI 1.09-15.32, p for trend=0.02) times higher risk of hyper-LDL-cholesterolemia, and 2.24 (95% CI 1.15-4.37, p for trend=0.004) times higher risk of dyslipidemia than those in the lowest tertile. Selenium is a significant effect-modifier for these associations; the highest tertile of toenail mercury were significantly associated with a higher risk of hypercholesterolemia (OR 5.25, 95% CI 1.04-26.38) and dyslipidemia (OR 2.98, 95% CI 1.16-7.66) compared to the lowest tertile at toenail selenium levels ≤0.685μg/g, while these associations became weak and non-significant, showing OR 0.98 and 95% CI 0.25-3.80 for hypercholesterolemia and OR 1.99 and 95% CI 0.73-5.45 for dyslipidemia at toenail selenium levels >0.685μg/g. We

  10. Selenium and Prostate Cancer Prevention: Insights from the Selenium and Vitamin E Cancer Prevention Trial (SELECT

    Directory of Open Access Journals (Sweden)

    Holly L. Nicastro

    2013-04-01

    Full Text Available The Selenium and Vitamin E Cancer Prevention Trial (SELECT was conducted to assess the efficacy of selenium and vitamin E alone, and in combination, on the incidence of prostate cancer. This randomized, double-blind, placebo-controlled, 2 × 2 factorial design clinical trial found that neither selenium nor vitamin E reduced the incidence of prostate cancer after seven years and that vitamin E was associated with a 17% increased risk of prostate cancer compared to placebo. The null result was surprising given the strong preclinical and clinical evidence suggesting chemopreventive activity of selenium. Potential explanations for the null findings include the agent formulation and dose, the characteristics of the cohort, and the study design. It is likely that only specific subpopulations may benefit from selenium supplementation; therefore, future studies should consider the baseline selenium status of the participants, age of the cohort, and genotype of specific selenoproteins, among other characteristics, in order to determine the activity of selenium in cancer prevention.

  11. Selenium and Prostate Cancer Prevention: Insights from the Selenium and Vitamin E Cancer Prevention Trial (SELECT)

    Science.gov (United States)

    Nicastro, Holly L.; Dunn, Barbara K.

    2013-01-01

    The Selenium and Vitamin E Cancer Prevention Trial (SELECT) was conducted to assess the efficacy of selenium and vitamin E alone, and in combination, on the incidence of prostate cancer. This randomized, double-blind, placebo-controlled, 2 × 2 factorial design clinical trial found that neither selenium nor vitamin E reduced the incidence of prostate cancer after seven years and that vitamin E was associated with a 17% increased risk of prostate cancer compared to placebo. The null result was surprising given the strong preclinical and clinical evidence suggesting chemopreventive activity of selenium. Potential explanations for the null findings include the agent formulation and dose, the characteristics of the cohort, and the study design. It is likely that only specific subpopulations may benefit from selenium supplementation; therefore, future studies should consider the baseline selenium status of the participants, age of the cohort, and genotype of specific selenoproteins, among other characteristics, in order to determine the activity of selenium in cancer prevention. PMID:23552052

  12. Selenium in Camel – A Review

    Directory of Open Access Journals (Sweden)

    Bernard Faye

    2009-07-01

    Full Text Available Requirements for trace minerals in camels, particularly selenium, are not well-known. Selenium supplementation using a pharmaceutical form or commercial mineral mixture is common practice in camels to address the cardiomyopathy often attributed to selenium deficiency. This supplementation is often empirical and based on estimated needs for cattle. Nowadays the use of selenium in animal foodstuffs is commonplace and further investigation of its metabolism (ingestion, dynamic of storage-destocking, excretion in camels is warranted. The present review aimed to synthesize all the experimental research (comparative selenium status in cow and camel, response to different levels of supplementation at different physiological stages, excretion maternal transfer, experimental toxicosis and field observations (deficiency, supplementation practices undertaken in camels. The results underline the particularity of the unique metabolic profile of the camel and lead to practical recommendations for supplementation in camels, highlighting its relative sensitivity to excess Se intake at lower levels than in cattle. The maximal tolerable dose is 8 mg and the recommended doses range from 2 to 4 mg.

  13. The Role of Magnesium and Calcium in Governing Yeast Agglomeration

    Directory of Open Access Journals (Sweden)

    Rosslyn M. Birch

    2002-01-01

    Full Text Available »Grit« formation by agglomerating cells of baker’s yeast is an idiosyncratic phenomenon of irreversible cellular aggregation that is detrimental to yeast quality. Agglomeration results in failure of rehydrated dried yeast to evenly resuspend and has economic consequences for both yeast manufacturers and bakers. Several environmental factors are implicated in governing yeast agglomeration, but no significant differences between 'gritty' and 'non-gritty' yeast in terms of cell hydrophobicity or flocculence have been reported. In this study, analysis of cellular metal ions has revealed high levels of calcium in 'gritty' strains of Saccharomyces cerevisiae, which suggests that calcium ions may positively influence agglomeration. In contrast, it was found that cellular magnesium levels were higher in 'non-gritty' yeast. Furthermore, by increasing magnesium concentrations in molasses yeast growth media, a reduction in cellular calcium was observed and this concomitantly reduced the tendency of cells to agglomerate and form grit. Magnesium thus acted antagonistically against calcium-induced agglomeration, possibly by blocking calcium binding to yeast cell surface receptors. Results suggested that yeast agglomeration and metal ion bioavailability were inextricably linked and the findings are discussed in relation to possible measures of alleviating cellular agglomeration in the production of baker’s yeast.

  14. Selenium balance in the adult cat in relation to intake of dietary sodium selenite and organically bound selenium

    NARCIS (Netherlands)

    Todd, S.E.; Thomas, D.G.; Hendriks, W.H.

    2012-01-01

    The response of cats to dietary sodium selenite (Na2SeO3) and organically bound selenium was studied in two separate studies with four cats per treatment and three levels of selenium supplementation (targets 1.0, 1.5 and 2.0 µg/g DM) for each Se source. Whole blood and plasma selenium concentrations

  15. Loss of selenium-binding protein 1 decreases sensitivity to clastogens and intracellular selenium content in HeLa cells

    Science.gov (United States)

    Selenium-binding protein 1 (SBP1) is not a selenoprotein but structurally binds selenium. Loss of SBP1 during carcinogenesis usually predicts poor prognosis. Because genome instability is a hallmark of cancer, we hypothesized that loss of SBP1 modulates cellular selenium content and the response of ...

  16. Selenium deficiency in children and adolescents nourished by parenteral nutrition and/or selenium-deficient enteral formula.

    Science.gov (United States)

    Etani, Yuri; Nishimoto, Yukiko; Kawamoto, Kouji; Yamada, Hiroyuki; Shouji, Yasuko; Kawahara, Hisayoshi; Ida, Shinobu

    2014-10-01

    The authors analyzed serum selenium levels of 95 children and adolescents with intestinal dysfunction and/or neurological disabilities [age range: 7 months-20 years; mean±standard deviation (SD): 8.0±5.3 years] who received parenteral nutrition (PN) and/or enteral nutrition (EN) with either reduced or no selenium doses for more than 3 months. Twenty-eight patients (29%) showed serum selenium levels below 4.0μg/dL. Five patients whose serum selenium levels were below 2μg/dL presented various clinical manifestations, including hair browning (n=5), macrocythemia (n=4), nail whitening (n=3) and cardiac dysfunction (n=1). None of these 5 patients were nourished through ordinary diets. Three of these patients were nourished through selenium-free enteral nutritional products, 1 through selenium-deficient PN and 1 through PN and a formula with reduced selenium. After selenium supplement therapy for 1 year, all 5 patients exhibited improvement in their serum selenium levels and clinical features of selenium deficiency. It is important to be cautious about secondary selenium deficiency in children and adolescents nourished only through EN/PN without an adequate dose of selenium. Copyright © 2014 Elsevier GmbH. All rights reserved.

  17. Levels of selenium in blood and tissues associated with some selenium deficiency diseases in New Zealand sheep.

    Science.gov (United States)

    Sheppard, A D; Blom, L; Grant, A B

    1984-06-01

    Whole bloods from weaned lambs with severe selenium responsive unthriftiness usually contain <5 ng Se/ml. Mildly or moderately affected lambs have blood levels of 5-10 ng/ml. Selenium responsive infertility in ewes appears to be associated with whole blood selenium levels below 10 ng/ml.

  18. Selenium coated CMOS passive pixel array for medical imaging

    Science.gov (United States)

    Majid, Shaikh Hasibul; Goldan, Amir H.; Hadji, Bahman; Belev, George; Kasap, Safa; Karim, Karim S.

    2011-03-01

    Digital imaging systems for medical applications use amorphous silicon thin-film transistor (TFT) technology due to its ability to be manufactured over large areas. However, TFT technology is far inferior to crystalline silicon CMOS technology in terms of the speed, stability, noise susceptibility, and feature size. This work investigates the feasibility of integrating an imaging array fabricated in CMOS technology with an a-Se detector. The design of a CMOS passive pixel sensor (PPS) array is presented, in addition to how an 8×8 PPS array is integrated with the 75 micron thick stabilized amorphous selenium detector. A non-linear increase in the dark current of 200 pA, 500 pA and 2 nA is observed with 0.27, 0.67 and 1.33 V/micron electric field respectively, which shows a successful integration of selenium layer with the CMOS array. Results also show that the integrated Selenium-CMOS PPS array has good responsivity to optical light and X-rays, leaving the door open for further research on implementing CMOS imaging architectures going forward. Demonstrating that the PPS chips using CMOS technology can use a-Se as a detector is thus the first step in a promising path of research, which should yield substantial and exciting results for the field. Though area may still prove challenging, larger CMOS wafers can be manufactured and tiled to allow for a large enough size for certain diagnostic imaging applications and potentially even large area applications like digital mammography.

  19. Medical geology of arsenic, selenium and thallium in China.

    Science.gov (United States)

    Li, Shehong; Xiao, Tangfu; Zheng, Baoshan

    2012-04-01

    Arsenic (As), selenium (Se) and thallium (Tl) are three trace metals (metalloids) of high concern in China because deficiency or excess expose can cause a range of endemic diseases, such as endemic arsenism, selenosis, Keshan disease (KD), Kashin-Beck disease (KBD) and thallotoxicosis. These specific endemic diseases were attributable for overabundance or deficiency (mainly referring to selenium) of these three elements in the local environment as a result of natural geochemical processes and/or anthropologic activities. The geochemistry and human health impacts of these three trace elements have been intensively studied since the 1970s in China, in terms of geochemical sources, distribution, transportation, health impact pathways, and prevention/remediation measures. Endemic arsenism in China are induced from the exposures of high As in either drinking water or domestic combustion of As-rich coals. Both endemic selenium deficiency and selenosis occurred in China. The KD and KBD were related to the deficiency of Se in the low-Se geological belt with Se contents in soil less than 0.125mg/kg stretching from northeast to southwest of China. Endemic selenosis occurred in areas with high Se concentrations in soils derived from the Se-enriched black carbonaceous siliceous rocks, carbonaceous shale and slate. Endemic Tl poisoning occurred in southwestern China due to Tl contamination in local drinking water and vegetables surrounding the Tl-rich sulfide mineralized areas. Some measures have been taken to control and remedy the endemic diseases with significant effects in reducing health risk and damage of As, Se and Tl. However, the states of the endemic diseases of As, Se and Tl in China are still serious in some areas, and substantial research efforts regarding the health impacts of these elements are further required. This paper reviews the progress of medical geology of As, Se and Tl in China, and provides with some outlooks for future research directions. Copyright

  20. Chemotropism during yeast mating.

    Science.gov (United States)

    Follette, Peter J; Arkowitz, Robert A

    2009-01-01

    Virtually all eukaryotic cells can grow in a polarized fashion in response to external signals. Cells can respond to gradients of chemoattractants or chemorepellents by directional growth, a process referred to as chemotropism. The budding yeast Saccharomyces cerevisiae undergoes chemotropic growth during mating, in which two haploid cells of opposite mating type grow toward one another. We have shown that mating pheromone gradients are essential for efficient mating in yeast and have examined the chemotropism defects of different yeast mutants. Two methods of assessing the ability of yeast strains to respond to pheromone gradients are presented here.

  1. Selenium and selenocysteine: roles in cancer, health, and development.

    Science.gov (United States)

    Hatfield, Dolph L; Tsuji, Petra A; Carlson, Bradley A; Gladyshev, Vadim N

    2014-03-01

    The many biological and biomedical effects of selenium are relatively unknown outside the selenium field. This fascinating element, initially described as a toxin, was subsequently shown to be essential for health and development. By the mid-1990s selenium emerged as one of the most promising cancer chemopreventive agents, but subsequent human clinical trials yielded contradictory results. However, basic research on selenium continued to move at a rapid pace, elucidating its many roles in health, development, and in cancer prevention and promotion. Dietary selenium acts principally through selenoproteins, most of which are oxidoreductases involved in diverse cellular functions. Published by Elsevier Ltd.

  2. Selenium supplementation for critically ill adults

    DEFF Research Database (Denmark)

    Allingstrup, Mikkel; Afshari, Arash

    2015-01-01

    was originally published in 2004 updated in 2007 and again 2015. OBJECTIVES: The primary objective was to examine the effect of nutrition supplemented with selenium or ebselen on mortality in critically ill patients.The secondary objective was to examine the relationship between selenium or ebselen...... supplementation and number of infections, duration of mechanical ventilation, length of intensive care unit stay and length of hospital stay. SEARCH METHODS: In this update, we searched the current issue of the Cochrane Central Register of Controlled Trials, the Cochrane Library (2014, Issue 5); MEDLINE (Ovid SP...... RESULTS: We included six new RCTs in this review update. In total we included 16 RCTs (2084 participants) in this review. Most trials were at high risk of bias. The availability of outcome data was limited and trials involving selenium supplementation were, with the exception of one trial, small regarding...

  3. Selenium nanoparticles as a nutritional supplement.

    Science.gov (United States)

    Skalickova, Sylvie; Milosavljevic, Vedran; Cihalova, Kristyna; Horky, Pavel; Richtera, Lukas; Adam, Vojtech

    2017-01-01

    Selenium is an essential trace element in the diet, required for maintenance of health and growth; however, its toxicity could cause serious damage depending on dose and chemical form. Selenium nanoparticles (SeNPs) represent what we believe to be a novel prospect for nutritional supplementation because of their lower toxicity and ability to gradually release selenium after ingestion. In this review, we discuss various forms and types of SeNPs, as well as the way they are synthesized. We also discuss absorption and bioavailability of nanoparticles within the organism. SeNPs demonstrate anticancer and antimicrobial properties that may contribute to human health, not only as dietary supplements, but also as therapeutic agents. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Plasma Selenium Levels in Chronic Cocaine Abuse.

    Science.gov (United States)

    Petrova, Julia; Manolov, Victor; Kiryakova, Theodora; Vasilev, Vasil; Tzatchev, Kamen; Borislav, Marinov; Radoslava, Emilova

    2016-01-01

    Cocaine abuse is a significant health problem worldwide. We aim to evaluate the role of selenium in oxidative stress in patients with cocaine related cardio- and cerebrovascular diseases. Selenium is of fundamental importance to human health. It is an essential component of several major metabolic pathways. We included 26 patients with chronic cocaine abuse separated into two groups according to duration of intake--from six months up to one year and more than a year, with and without only vascular incidents (TIA, stroke, myocardial infarction), or presence of hypertension. All included groups were analyzed for laboratory parameters: CBC, CRP, AST, ALT, γ-GT, serum creatinine, urea, K, Na, and Ca. Main risk factors were evaluated: total cholesterol, LDL and HDL-cholesterol, triglycerides, glucose, and selenium. Our result shows that in the first group only 20% have cardiovascular problems. In the group with cocaine abuse more than a year, number of vascular incidents has increased (58.3%). Patients from the group cocaine abuse up to 1 year showed no changes in lipid profile, but cocaine abuse more than a year showed interesting changes in the lipid profile. We found a high positive correlation between the two cocaine groups for plasma selenium concentrations. This means that after the first six months oxidative stress has occured. It increases with duration of cocaine abuse. CRP correlated positively between these two groups, showing an endothelial function disorder. Development of oxidative stress increased with cocaine abuse, which leads to lower plasma selenium levels in patients with different duration of intake--less and more than a year. It is possible to supplement selenium during the early period of cocaine dependence to prevent hard vascular accidents, which are common after more than one year of cocaine abuse.

  5. Selenium supplementation can slow the development of naphthalene cataract.

    Science.gov (United States)

    Zhu, Xiangjia; Lu, Yi

    2012-03-01

    To evaluate the effect of selenium supplementation on the progress of naphthalene cataract. Sprague-Dawley rats were randomly divided into five groups as follows: normal control, naphthalene control and selenium-supplemented groups (Selenium I, II and III, which were orally administrated with selenium at doses of 0.0104 mg/kg, 0.0208 mg/kg and 0.0416 mg/kg, respectively). All the intervention groups were orally administered with 10% naphthalene solution for 5 weeks. The lens density of each group was determined by photography. Moreover, glutathione peroxidase (GPx) activity in the lens, erythrocyte and plasma was investigated. In addition, lens glutathione (GSH), malondialdehyde (MDA) and hydroxyl radical levels were evaluated. Selenium level in aqueous humor was determined using atomic absorption spectrometry. The maximum, mean and minimum densities of lens opacities were lower in Selenium group II and III than those in naphthalene group. The maximum density of the lens increased more slowly in Selenium group I than that in naphthalene controls. In selenium-supplemented groups, blood and lens GPx activities as well as aqueous humor selenium level increased significantly. Selenium supplementation also significantly ameliorated the decrease in GSH level and increase in MDA and hydroxyl radical levels in the lens of naphthalene-treated rats. Selenium supplementation could slow the development of naphthalene cataract possibly by attenuating the oxidative stress in the lens.

  6. Bioaccumulation and distribution of selenium in Enterococcus durans.

    Science.gov (United States)

    Pieniz, Simone; Andreazza, Robson; Mann, Michele Bertoni; Camargo, Flávio; Brandelli, Adriano

    2017-03-01

    Selenium is an essential nutrient for all living organisms. Under appropriate conditions lactic acid bacteria (LAB) are capable for accumulating large amounts of trace elements, such as selenium, and incorporating them into organic compounds. In this study, the capacity of selenium bioaccumulation by Enterococcus durans LAB18s was evaluated. The distribution of organic selenium in selenium-enriched E. durans LAB18s biomass was analyzed, and the highest percentage of organic selenium was found in the fraction of total protein, followed by the fractions of polysaccharides and nucleic acids. When the protein fraction was obtained by different extractions (water, NaCl, ethanol and NaOH) it was demonstrated that alkali-soluble protein showed the higher Selenium content. Analysis of protein fractions by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) revealed that selenium was present in the proteins ranging from 23 to 100kDa. The cells were analyzed by scanning electron microscopy (SEM); scanning electron microscopy/energy dispersive spectrometry (SEM/EDS) and transmission electron microscopy (TEM). SEM, TEM and SEM/EDS showed the morphology, the selenium particles bioaccumulated into and on the cells and the amounts of selenium present into the cells, respectively. Thus, the isolate E. durans LAB18s can be a promising probiotic to be used as selenium-enriched biomass in feed trials. Copyright © 2016 Elsevier GmbH. All rights reserved.

  7. [The role of selenium in endocrine system diseases].

    Science.gov (United States)

    Balázs, Csaba; Rácz, Károly

    2013-10-13

    Oxygen derived free radicals, generated by a number of cellular reactions, include superoxide anion, hydrogen peroxide and hydroxyl radicals. They exert their cytotoxic effects mainly via peroxidation of the cell membrane resulting in the loss of membrane integrity. The essential trace element, selenium exerts complex effects on the endocrine systems, partly due to its antioxidant capacity. Well-characterized selenoproteins include iodothyronine deiodinases, glutathione peroxidases and thioredoxin reductases involved in thyroid hormone metabolism and protection from oxidative damage. The value of selenium supplementation in autoimmune thyroid disorders has been investigated and most studies confirmed the beneficial effect of selenium supplementation in Hashimoto's and Graves's diseases. Recently, selenium proved to be effective in mild inflammatory orbitopathy. There are a number of reports about the effect of selenium in diabetes mellitus, but the data are controversial as both insulin-like and diabetes-inducing effects of selenium have been described. Selenium was successfully used in both female and male infertility of autoimmune origin.

  8. Selenium supplementation in radiotherapy patients: do we need to measure selenium levels in serum or blood regularly prior radiotherapy?

    Science.gov (United States)

    Muecke, Ralph; Micke, Oliver; Schomburg, Lutz; Kisters, Klaus; Buentzel, Jens; Huebner, Jutta; Kriz, Jan

    2014-12-16

    Considering the review by Puspitasari and colleagues, an additional discussion of the endpoints of the Se supplementation studies described would be helpful. In our view, selenium can safely be given to selenium-deficient cancer patients prior to and during radiotherapy. Therefore, in order to help the radiation oncologist in decision making, we strongly advocate to determine the selenium status prior to and during a potential adjuvant selenium supplementation, e.g. when trying to ease the side-effects of radiation treatment or in the aftercare situation when the selenium status may become insufficient.

  9. In vivo and in vitro testing for selenium and selenium compounds bioavailability assessment in foodstuff.

    Science.gov (United States)

    Moreda-Piñeiro, Jorge; Moreda-Piñeiro, Antonio; Bermejo-Barrera, Pilar

    2017-03-04

    The assessment of selenium and selenium species bioavailability in foodstuff is of special concern on the context of human nutrition. In vivo (human and animal), and in vitro tests are important approaches for estimating the bioavailability of toxic and essential compounds to humans. An overview on in vivo and in vitro bioavailability assays for releasing selenium and selenium species in foodstuffs is summarized. Se and Se species content in a foodstuff critically influence Se bioavailability and bioactivity to humans and animals. Se bioavailability is affected by foodstuff-matrix major composition and minor components. Foodstuffs processing and/or treatments could enhancement or decrease Se bioavailability. Experimental conditions such as the selection of healthy status of examined people (in in vivo humans approaches), the selection of animal model (in vivo animals approaches), or the selection of GI conditions (in in vitro tests) could determines the results. Thus, international standardized protocol for in vivo and in vitro approaches assessment is mandatory.

  10. Changes in selenium speciation associated with increasing tissue concentrations of selenium in wheat grain.

    Science.gov (United States)

    Cubadda, Francesco; Aureli, Federica; Ciardullo, Silvia; D'Amato, Marilena; Raggi, Andrea; Acharya, Raghunath; Reddy, Ramana A V; Prakash, Nagaraja Tejo

    2010-02-24

    Wheat (Triticum aestivum) collected in the Nawanshahr-Hoshiarpur Region (Punjab, India) showed the highest selenium concentrations ever recorded in cereal grains (29-185 microg g(-1)). There was a strong positive relationship between the selenium content in shoots and that in kernels, showing that grain selenium concentration can be predicted from that in the vegetative tissues of the plant. The identity and content of the selenocompounds in the grain samples and in wheat-based reference materials were investigated by HPLC-ICP-dynamic reaction cell-MS. Reversed-phase, cation exchange, and anion exchange HPLC were used to separate the selenium species after ultrasound-assisted enzymatic extraction with an ultrasonic probe. Selenomethionine and selenate accounted for 72-85% and 2-6% of the sum of the selenium species, respectively. The proportion of organic Se species varied with increasing Se content; namely, SeMet showed a relative reduction whereas the other organoselenium compounds increased up to 18-22% of the total chromatographed selenium. Se-methyl-selenocysteine was detected as a minor compound (0.2-0.5%) in high-Se wheat by both reversed-phase and cation exchange HPLC using retention time matching with the standard substance spiked to the sample extracts. Regular consumption of locally produced wheat-based food items may lead the population of the study area to an excessive intake of selenium. On the other hand, the large predominance of selenomethionine shows that local wheat can be a promising raw material for naturally enriched products to be used to supplement human and animal diets in low selenium areas.

  11. Post-weaning selenium and folate supplementation affects gene and protein expression and global DNA methylation in mice fed high-fat diets

    Science.gov (United States)

    2013-01-01

    Background Consumption of high-fat diets has negative impacts on health and well-being, some of which may be epigenetically regulated. Selenium and folate are two compounds which influence epigenetic mechanisms. We investigated the hypothesis that post-weaning supplementation with adequate levels of selenium and folate in offspring of female mice fed a high-fat, low selenium and folate diet during gestation and lactation will lead to epigenetic changes of potential importance for long-term health. Methods Female offspring of mothers fed the experimental diet were either maintained on this diet (HF-low-low), or weaned onto a high-fat diet with sufficient levels of selenium and folate (HF-low-suf), for 8 weeks. Gene and protein expression, DNA methylation, and histone modifications were measured in colon and liver of female offspring. Results Adequate levels of selenium and folate post-weaning affected gene expression in colon and liver of offspring, including decreasing Slc2a4 gene expression. Protein expression was only altered in the liver. There was no effect of adequate levels of selenium and folate on global histone modifications in the liver. Global liver DNA methylation was decreased in mice switched to adequate levels of selenium and folate, but there was no effect on methylation of specific CpG sites within the Slc2a4 gene in liver. Conclusions Post-weaning supplementation with adequate levels of selenium and folate in female offspring of mice fed high-fat diets inadequate in selenium and folate during gestation and lactation can alter global DNA methylation in liver. This may be one factor through which the negative effects of a poor diet during early life can be ameliorated. Further research is required to establish what role epigenetic changes play in mediating observed changes in gene and protein expression, and the relevance of these changes to health. PMID:23497688

  12. Prions in Yeast

    Science.gov (United States)

    Liebman, Susan W.; Chernoff, Yury O.

    2012-01-01

    The concept of a prion as an infectious self-propagating protein isoform was initially proposed to explain certain mammalian diseases. It is now clear that yeast also has heritable elements transmitted via protein. Indeed, the “protein only” model of prion transmission was first proven using a yeast prion. Typically, known prions are ordered cross-β aggregates (amyloids). Recently, there has been an explosion in the number of recognized prions in yeast. Yeast continues to lead the way in understanding cellular control of prion propagation, prion structure, mechanisms of de novo prion formation, specificity of prion transmission, and the biological roles of prions. This review summarizes what has been learned from yeast prions. PMID:22879407

  13. The yeast Golgi apparatus.

    Science.gov (United States)

    Suda, Yasuyuki; Nakano, Akihiko

    2012-04-01

    The Golgi apparatus is an organelle that has been extensively studied in the model eukaryote, yeast. Its morphology varies among yeast species; the Golgi exists as a system of dispersed cisternae in the case of the budding yeast Saccharomyces cerevisiae, whereas the Golgi cisternae in Pichia pastoris and Schizosaccharomyces pombe are organized into stacks. In spite of the different organization, the mechanism of trafficking through the Golgi apparatus is believed to be similar, involving cisternal maturation, in which the resident Golgi proteins are transported backwards while secretory cargo proteins can stay in the cisternae. Questions remain regarding the organization of the yeast Golgi, the regulatory mechanisms that underlie cisternal maturation of the Golgi and transport machinery of cargo proteins through this organelle. Studies using different yeast species have provided hints to these mechanisms. © 2011 John Wiley & Sons A/S.

  14. Effect of high levels of organic selenium on glutation-peroxidase (GSH-Px activity in blood plasma of broilers

    Directory of Open Access Journals (Sweden)

    Joksimović-Todorović Mirjana

    2005-01-01

    Full Text Available An experiment lasting 45 days was performed on 125 Hybro broilers divided into five groups. All compounds for broiler feed mixes used in the experiment contained 0.15 mg Se/kg, in the form of sodium selenite. The control group (K-group of broilers was fed mixes without added organic selenium, and the experimental groups with mixes to which selenium, in the form of selenized-yeast, was added in quantities of 2, 5, 10, or 15 mg/kg. Selenized yeast (ICN - Gaienika was obtained from beer yeast and contained 1.51, or 1.45 mg/g total, or organically bound selenium. At the beginning of the fattening period, GSH-Px plasma activity in broilers of the K-group ranged around 16.55 μkat/L, while GSH-Px plasma activity in broilers of experimental groups was statistically significantly higher, but without any major differences among the individual groups (on the average 25.53fjkat/L. In the blood plasma of K-group, GSH-Px activity dropped already in the second week of life and was maintained at a relatively constant level (about 10 μkat/L until the end of the experiment. The same phenomenon was observed in the experimental groups, but the trend of declining GSH-Px activity in blood plasma was more expressed, and, contrary to the control group, was expressed also in the later phases of the experiment. In the 3rd week of the fattening period, GSH-Px plasma activity in broilers of the control and experimental groups was relatively equal, and then the plasma activity of GSH-Px in broilers of the experimental groups decreased, but there were no major differences among the individual groups.

  15. BLOOD SELENIUM CONCENTRATION AFFECT MASTITIS AND MILK QUALITY IN DAIRY COWS

    Directory of Open Access Journals (Sweden)

    Davidov Ivana

    2013-02-01

    Full Text Available Milk quality is usually defined in terms of mastitis. Milk with somatic cell count low then 400.000/ml and visibly normal (no clots is considered high quality. Thirty Holstein cows were used in the study to determine affect blood serum selenium concentration on mastitis and milk quality. Cows received ad libitum access to potable water and daily 0.3 mg/kg inorganic selenium supplementation in food. Blood and milk samples were taken at first and sixth lactating month. Mean selenium blood serum concentrations were found to be lower within first lactating month, and then increased in the sixth lactating month. Average somatic cell count at first lactating month was 450.000/ml of milk and at sixth lactating month was 355.000/ml. On the basis of these results it can be conclude that selenium have importance in proper functioning of the mammary glands of cows, and in reducing mastitis and in improving milk quality.

  16. The Relationship between Selenium and T3 in Selenium Supplemented and Nonsupplemented Ewes and Their Lambs

    Directory of Open Access Journals (Sweden)

    Abd Elghany Hefnawy

    2014-01-01

    Full Text Available Twenty pregnant ewes were selected and classified into two groups. The first group received subcutaneous selenium supplementation (0.1 mg of sodium selenite/kg BW at the 8th and 5th weeks before birth and 1st week after birth while the other was control group without selenium injection. Maternal plasma and serum samples were collected weekly from the 8th week before birth until the 8th week after birth and milk samples were taken from ewes weekly, while plasma and serum samples were collected at 48 hours, 1st, 2nd, 3rd, 5th, and 8th weeks after birth from the newborn lambs. Results demonstrated significant positive relationship between maternal plasma selenium and serum T3 in supplemented and control ewes (r=0.69 to 0.72, P<0.05. There was significant (P<0.001 increase in T3 in supplemented ewes and their lambs until the 8th week after birth. There was positive relationship between milk, selenium concentration, and serum T3 in the newborn lambs of the supplemented group (r=0.84, P<0.01, while the relationship was negative in the control one (r=-0.89, P<0.01. Muscular and thyroid pathological changes were independent of selenium supplementation. Selenium supplementation was important for maintaining T3 in ewes and newborn lambs until the 8th week after birth.

  17. Ovine offspring growth and diet digestibility are influenced by maternal selenium supplementation and nutritional intake during pregnancy despite a common postnatal diet.

    Science.gov (United States)

    Neville, T L; Caton, J S; Hammer, C J; Reed, J J; Luther, J S; Taylor, J B; Redmer, D A; Reynolds, L P; Vonnahme, K A

    2010-11-01

    Lambs born from feed-restricted or overfed ewes can be lighter at birth, whereas maternal Se supplementation can increase fetal size near term. We hypothesized that birth weight would be inversely related to feed efficiency and growth rates during postnatal development. To examine the effects of maternal dietary Se and nutrient restriction or excess on postnatal lamb growth, diet digestibility, and N retention, 82 ewe lambs (52.2 ± 0.8 kg) were allotted randomly to 1 of 6 treatments in a 2 × 3 factorial arrangement. Factors were dietary Se [adequate Se (9.5 μg/kg of BW; ASe) vs. high Se (Se-enriched yeast; 81.8 μg/kg of BW; HSe)] and maternal nutritional intake [60% (restricted, RES), 100% (control, CON), or 140% (high, HI) of NRC requirements]. Selenium treatments began at breeding. Nutritional treatments began on d 50 of gestation. Lambs were immediately removed from their dams at parturition, provided artificial colostrum, and fed milk replacer until weaning. After weaning, lambs were maintained using common management and on common diets until necropsy at 180 d. Male and female lambs from RES-fed ewes were lighter (P ≤ 0.03) at birth than lambs from CON-fed ewes, with lambs from HI-fed ewes being intermediate. Although maternal nutritional intake influenced (P growth and efficiency of growth in offspring despite similar postnatal management.

  18. Selenium supplementation improves the nutritional status of hemodialysis patients: a randomized, double-blind, placebo-controlled trial.

    Science.gov (United States)

    Salehi, Moosa; Sohrabi, Zahra; Ekramzadeh, Maryam; Fallahzadeh, Mohammad Kazem; Ayatollahi, Maryam; Geramizadeh, Bita; Hassanzadeh, Jafar; Sagheb, Mohammad Mahdi

    2013-03-01

    Malnutrition is highly prevalent in hemodialysis (HD) patients. These patients have high levels of oxidative stress and inflammation which can subsequently induce malnutrition. Selenium levels have been found to be decreased in HD patients. As selenium deficiency leads to oxidative stress and inflammatory response, the aim of this study was to evaluate the effects of selenium supplementation on oxidative and inflammatory markers and the nutritional status of HD patients. In this randomized double-blind placebo-controlled trial, 80 patients on stable HD for at least 3 months without any acute illness or active infections were randomly allocated to two equal groups to receive one selenium (200 µg) or placebo capsule daily for 12 weeks. Serum levels of lipoproteins, malondialdehyde (MDA), interleukin-6 (IL-6), high-sensitivity C-reactive protein (HSCRP), homocysteine, ferritin and transferrin as well as the subjective global assessment (SGA) score, malnutrition-inflammation score (MIS) and hemoglobin (Hb) levels were measured at the baseline and at the end of the treatment phase. The primary outcome was a change in the nutritional status measured by the SGA score from the baseline towards the end of the treatment phase of the study. The SGA score and MIS decreased significantly in the selenium group compared to the placebo group (P supplementation also hindered an increase in IL-6 levels compared with the placebo group (P = 0.016). There were no significant differences between the selenium and placebo groups in terms of changes in serum levels of lipoproteins, HSCRP, homocysteine, ferritin and transferrin or Hb levels. This study shows that selenium may be an effective complementary supplement for reducing the severity of malnutrition in HD patients through alleviating oxidative stress and inflammation.

  19. Flor yeast: new perspectives beyond wine ageing

    Directory of Open Access Journals (Sweden)

    Jean-luc eLegras

    2016-04-01

    Full Text Available The most important dogma in white-wine production is the preservation of the wine aroma and the limitation of the oxidative action of oxygen. In contrast, the ageing of Sherry and Sherry-like wines is an aerobic process that depends on the oxidative activity of flor strains of Saccharomyces cerevisiae. Under depletion of nitrogen and fermentable carbon sources, these yeast produce aggregates of floating cells and form an air-liquid biofilm on the wine surface, which is also known as the velum or flor. This behaviour is due to genetic and metabolic peculiarities that differentiate flor yeast from other wine yeast. This review will focus first on the most updated data obtained through the analysis of flor yeast with -omic tools. Comparative genomics, proteomics and metabolomics of flor and wine yeast strains are shedding new light on several features of these special yeast, and in particular, they have revealed the extent of proteome remodelling imposed by the biofilm life-style. Finally, new insights in terms of promotion and inhibition of biofilm formation through small molecules, amino acids and di/tri-peptides, and novel possibilities for the exploitation of biofilm immobilisation within a fungal hyphae framework, will be discussed.

  20. Mercury and selenium content of Taiwanese seafood.

    Science.gov (United States)

    Fang, G C; Nam, D H; Basu, N

    2011-01-01

    Fish consumption is avid in Taiwan (and other Asian nations), but little is known about the mercury and selenium content in local seafood. This paper reports on total mercury, methylmercury and selenium levels from 14 commonly consumed seafood items obtained from Taichung, Taiwan. Mean total mercury concentrations varied nearly 100-fold across species. Fifty per cent of the marlins sampled and 35% of the sharks exceeded the 0.3 µg g(-1) US Environmental Protection Agency (USEPA) guideline. Methylmercury comprised a majority of the total mercury in all species. In all species studied there was a molar excess of selenium over mercury. The rank order of mean selenium-mercury molar ratios was red tilapia (166.8) > abura (87.9) > river prawn (82.4) > whiteleg shrimp (64.2) > butterfish (44.6) > milkfish (37.0) > tuna (15.6) > grouper (13.9) > ayu (13.4) > coral hind (13.0) > weever (11.8) > saury (9.0) > shark (7.8) > marlin (4.2).

  1. Selecting Lentil Accessions for Global Selenium Biofortification

    Science.gov (United States)

    Biofortification of lentil (Lens culinaris Medikus.) has the potential to provide adequate daily selenium (Se) to human diets. The objectives of this study were to (1) determine how low dose Se fertilizer application at germination affects seedling biomass, antioxidant activity, and Se uptake of 26 ...

  2. Selenium as a cancer preventive agent

    Science.gov (United States)

    Most epidemiological studies have shown inverse associations of selenium (Se) status and cancer risk. Almost all experimental animal studies have shown that supranutritional exposures of Se can reduce tumor yield. Each of the limited number of clinical intervention trials conducted to date has found...

  3. Selenium speciation in anaerobic granular sludge

    NARCIS (Netherlands)

    Lenz, M.; Gmerek, A.; Lens, P.N.L.

    2006-01-01

    Chromatographic (IC-CD, GC-FID) and spectroscopic (XRD) techniques that allow the specific determination of several selenium species present or formed during bioremediation processes of selenate contaminated drinking, ground, or wastewaters have been established. The developed techniques are shown

  4. Ameliorative effects of selenium and zinc

    African Journals Online (AJOL)

    The aim of this study was to determine the effect of a sub-acute 4-week exposure to methidathion (MD) on the hematological system and hepatic integrity of rats. We also assessed whether co-administration of micronutrients such as selenium (Se) and zinc (Zn) prevented MD-induced hepatic damage. Rats were randomly ...

  5. Selenium in Oklahoma ground water and soil

    Energy Technology Data Exchange (ETDEWEB)

    Atalay, A.; Vir Maggon, D.

    1991-03-30

    Selenium with a consumption of 2 liters per day (5). The objectives of this study are: (1) to determine the concentrations of Se in Oklahoma ground water and soil samples. (2) to map the geographical distribution of Se species in Oklahoma. (3) to relate groundwater depth, pH and geology with concentration of Se.

  6. Genetic Determinants of Responses to Selenium Supplementation

    Science.gov (United States)

    In a cohort of healthy adults (106 M, 155 W) in eastern North Dakota, we determined the relationships of five biomarkers of selenium (Se) status (plasma Se, serum selenoprotein P [SePP], plasma glutathione peroxidase [GPX3] activity, buccal cell Se, urine Se) to genotype for four selenoproteins (cyt...

  7. Responses to Selenium Supplementation in Healthy Americans

    Science.gov (United States)

    To determine dose-response relationships of selenium (Se) intake and markers of Se status in healthy, non-deficient subjects, we conducted a 12 mo. intervention using Se supplements (0, 50, 100 or 200 ug Se [as L-selenomethionine]/d) in a group of 106 men and 155 women. At baseline, this cohort, non...

  8. Status of selenium in cancer prevention

    Science.gov (United States)

    An abundance of data indicate that selenium (Se) can be antitumorigenic. Those data, mostly from controlled studies using animal tumor models and some from clinical studies in free-living people, indicate that treatment with Se in the absence of nutritional Se-deficiency, can reduce cancer risk. T...

  9. Chapter 6: Selenium Toxicity to Aquatic Organisms

    Science.gov (United States)

    This chapter addresses the characteristics and nature of organic selenium (Se) toxicity to aquatic organisms, based on the most current state of scientific knowledge. As such, the information contained in this chapter relates to the 'toxicity assessment' phase of aquatic ecologi...

  10. Selenium supplementation and prostate cancer mortality.

    Science.gov (United States)

    Kenfield, Stacey A; Van Blarigan, Erin L; DuPre, Natalie; Stampfer, Meir J; L Giovannucci, Edward; Chan, June M

    2015-01-01

    Few studies have evaluated the relation between selenium supplementation after diagnosis and prostate cancer outcomes. We prospectively followed 4459 men initially diagnosed with nonmetastatic prostate cancer in the Health Professionals Follow-Up Study from 1988 through 2010 and examined whether selenium supplement use (from selenium-specific supplements and multivitamins) after diagnosis was associated with risk of biochemical recurrence, prostate cancer mortality, and, secondarily, cardiovascular disease mortality and overall mortality, using Cox proportional hazards models. All P values were from two-sided tests. We documented 965 deaths, 226 (23.4%) because of prostate cancer and 267 (27.7%) because of cardiovascular disease, during a median follow-up of 8.9 years. In the biochemical recurrence analysis, we documented 762 recurrences during a median follow-up of 7.8 years. Crude rates per 1000 person-years for prostate cancer death were 5.6 among selenium nonusers and 10.5 among men who consumed 140 or more μg/day. Crude rates per 1000 person-years were 28.2 vs 23.5 for all-cause mortality and 28.4 vs 29.3 for biochemical recurrence, for nonuse vs highest-dose categories, respectively. In multivariable analyses, men who consumed 1 to 24 μg/day, 25 to 139 μg/day, and 140 or more μg/day of supplemental selenium had a 1.18 (95% confidence interval [CI] = 0.73 to 1.91), 1.33 (95% CI = 0.77 to 2.30), and 2.60-fold (95% CI = 1.44 to 4.70) greater risk of prostate cancer mortality compared with nonusers, respectively, P trend = .001. There was no statistically significant association between selenium supplement use and biochemical recurrence, cardiovascular disease mortality, or overall mortality. Selenium supplementation of 140 or more μg/day after diagnosis of nonmetastatic prostate cancer may increase risk of prostate cancer mortality. Caution is warranted regarding usage of such supplements among men with prostate cancer. © The Author 2014. Published by

  11. Selenium Supplementation and Prostate Cancer Mortality

    Science.gov (United States)

    Van Blarigan, Erin L.; DuPre, Natalie; Stampfer, Meir J.; L. Giovannucci, Edward; Chan, June M.

    2015-01-01

    Background: Few studies have evaluated the relation between selenium supplementation after diagnosis and prostate cancer outcomes. Methods: We prospectively followed 4459 men initially diagnosed with nonmetastatic prostate cancer in the Health Professionals Follow-Up Study from 1988 through 2010 and examined whether selenium supplement use (from selenium-specific supplements and multivitamins) after diagnosis was associated with risk of biochemical recurrence, prostate cancer mortality, and, secondarily, cardiovascular disease mortality and overall mortality, using Cox proportional hazards models. All P values were from two-sided tests. Results: We documented 965 deaths, 226 (23.4%) because of prostate cancer and 267 (27.7%) because of cardiovascular disease, during a median follow-up of 8.9 years. In the biochemical recurrence analysis, we documented 762 recurrences during a median follow-up of 7.8 years. Crude rates per 1000 person-years for prostate cancer death were 5.6 among selenium nonusers and 10.5 among men who consumed 140 or more μg/day. Crude rates per 1000 person-years were 28.2 vs 23.5 for all-cause mortality and 28.4 vs 29.3 for biochemical recurrence, for nonuse vs highest-dose categories, respectively. In multivariable analyses, men who consumed 1 to 24 μg/day, 25 to 139 μg/day, and 140 or more μg/day of supplemental selenium had a 1.18 (95% confidence interval [CI] = 0.73 to 1.91), 1.33 (95% CI = 0.77 to 2.30), and 2.60-fold (95% CI = 1.44 to 4.70) greater risk of prostate cancer mortality compared with nonusers, respectively, P trend = .001. There was no statistically significant association between selenium supplement use and biochemical recurrence, cardiovascular disease mortality, or overall mortality. Conclusion: Selenium supplementation of 140 or more μg/day after diagnosis of nonmetastatic prostate cancer may increase risk of prostate cancer mortality. Caution is warranted regarding usage of such supplements among men with prostate

  12. An examination of the selenium nutrition of sheep in Victoria.

    Science.gov (United States)

    Caple, I W; Andrewartha, K A; Edwards, S J; Halpin, C G

    1980-04-01

    The selenium nutrition of sheep throughout Victoria was assessed by a survey of the blood glutathione peroxidase activity in 708 flocks. It was shown that the blood glutathione peroxidase activity in sheep had a seasonal variation with lowest levels in the spring. The enzyme activity was correlated with the blood selenium concentration. Areas where blood selenium was less than 0.03 micrograms/ml in spring were defined. Sheep with low selenium nutrition were grazing pastures in the high rainfall areas on acid soils, particularly those derived from granite. Selenium concentrations in pasture samples examined were greater than 0.02 mg/kg, and it was found that superphosphate application had no significant effect on the selenium content of pasture. However, management practices such as high stocking rates and rates of application of superphosphate to pasture were associated with low blood glutathione peroxidase activities in sheep. It was concluded that the selenium nutrition of most of the sheep flocks in Victoria is adequate, and that the deficient areas are localised. There seems little requirement for supplementation of adult sheep. As the delayed type of white muscle disease in spring lambs appears to be the main selenium-responsive disorder, direct supplementation of lambs in the low selenium areas would be the most effective method of ensuring adequate selenium nutrition.

  13. [Selenium and cataract--risk factor or useful dietary supplement?].

    Science.gov (United States)

    Dawczynski, J; Winnefeld, K; Königsdörffer, E; Augsten, R; Blum, M; Strobel, J

    2006-08-01

    The exact role of selenium in cataract development is still unclear. Both protective and toxic effects and mechanisms have been postulated in the past. Accordingly, the selenium contents in human lenses and blood sera in different forms of cataract were investigated. 123 patients (76 female and 37 male) with a mean age of 69.8 years (range: 17 to 91 years) were enrolled in this study. Overall, 84 lenses (after ECCE) and 110 blood serum samples were investigated by atomic absorption spectroscopy. Interpretation of data was accompanied by exact preoperative investigations including Scheimpflug techniques. A significant increase of selenium content of the lenses was found with increasing lens opacification and colouration. Lenses with a mature cataract showed the highest selenium contents in the lens compared to other cataract forms. Opposite results were detected in blood serum. Lenses of diabetics showed already at a younger age changes in selenium content. Smokers showed both decreased selenium contents in the lens and decreased selenium concentration in blood serum. An obvious correlation between the type of cataract and selenium content of the lens seems to exist. The question by which mechanism selenium acts directly or by selenium-dependent enzymes acts lens opacification remains speculative up to now.

  14. Review - Selenium - Its metabolism and relation to exercise.

    Science.gov (United States)

    Baltaci, Abdulkerim Kasim; Mogulkoc, Rasim; Akil, Mustafa; Bicer, Mursel

    2016-09-01

    Selenium (Se), which is commonly found in nature, is one of the essential trace elements necessary for the normal development of human and animal organisms. Selenium was first defined in 1818 by the Swedish chemist Berzelius in sulfuric acid residues. At the end of 1960s, the role of selenium in human health began to attract attention and human diseases that resembled animal diseases responding to selenium was started to be investigated. Selenium, which is highly important for human health, is necessary for a variety of metabolic processes, including thyroid hormone metabolism, protection against oxidative stress and immunity functions. Selenium is a molecule that activates glutathione peroxidase, and thus, it is involved in the antioxidant mechanisms that prevent oxidant damage. Exhaustive physical exercise is known to cause oxidant damage, probably by promoting free radical production in many tissues, including muscle, liver, heart and lungs in animals. The increase in oxidative stress during exercise and recognition of selenium's stimulation of antioxidant activity inevitably suggest a relation between selenium and exercise. The present review aims to provide information on selenium metabolism and the relation between selenium and exercise.

  15. Selenium and Thyroid Disease: From Pathophysiology to Treatment

    Directory of Open Access Journals (Sweden)

    Mara Ventura

    2017-01-01

    Full Text Available Introduction. Selenium is a micronutrient embedded in several proteins. In adults, the thyroid is the organ with the highest amount of selenium per gram of tissue. Selenium levels in the body depend on the characteristics of the population and its diet, geographic area, and soil composition. In the thyroid, selenium is required for the antioxidant function and for the metabolism of thyroid hormones. Methods. We performed a review of the literature on selenium’s role in thyroid function using PubMed/MEDLINE. Results. Regarding thyroid pathology, selenium intake has been particularly associated with autoimmune disorders. The literature suggests that selenium supplementation of patients with autoimmune thyroiditis is associated with a reduction in antithyroperoxidase antibody levels, improved thyroid ultrasound features, and improved quality of life. Selenium supplementation in Graves’ orbitopathy is associated with an improvement of quality of life and eye involvement, as well as delayed progression of ocular disorders. The organic form of selenium seems to be the preferable formulation for supplementation or treatment. Conclusion. Maintaining a physiological concentration of selenium is a prerequisite to prevent thyroid disease and preserve overall health. Supplementation with the organic form is more effective, and patients with autoimmune thyroiditis seem to have benefits in immunological mechanisms. Selenium supplementation proved to be clinically beneficial in patients with mild to moderate Graves’ orbitopathy.

  16. Thyroid hormones regulate selenoprotein expression and selenium status in mice.

    Directory of Open Access Journals (Sweden)

    Jens Mittag

    Full Text Available Impaired expression of selenium-containing proteins leads to perturbed thyroid hormone (TH levels, indicating the central importance of selenium for TH homeostasis. Moreover, critically ill patients with declining serum selenium develop a syndrome of low circulating TH and a central downregulation of the hypothalamus-pituitary-thyroid axis. This prompted us to test the reciprocal effect, i.e., if TH status would also regulate selenoprotein expression and selenium levels. To investigate the TH dependency of selenium metabolism, we analyzed mice expressing a mutant TH receptor α1 (TRα1+m that confers a receptor-mediated hypothyroidism. Serum selenium was reduced in these animals, which was a direct consequence of the mutant TRα1 and not related to their metabolic alterations. Accordingly, hyperthyroidism, genetically caused by the inactivation of TRβ or by oral TH treatment of adult mice, increased serum selenium levels in TRα1+m and controls, thus demonstrating a novel and specific role for TRα1 in selenium metabolism. Furthermore, TH affected the mRNA levels for several enzymes involved in selenoprotein biosynthesis as well as serum selenoprotein P concentrations and the expression of other antioxidative selenoproteins. Taken together, our results show that TH positively affects the serum selenium status and regulates the expression of several selenoproteins. This demonstrates that selenium and TH metabolism are interconnected through a feed-forward regulation, which can in part explain the rapid parallel downregulation of both systems in critical illness.

  17. Low plasma selenium concentrations in critically ill children: the interaction effect between inflammation and selenium deficiency

    Science.gov (United States)

    2014-01-01

    Introduction Low plasma selenium concentrations are frequent in critically ill patients. However, whether this is due to systemic inflammation, a deficient nutritional state or both is still not clear. We aimed to determine the factors associated with low plasma selenium in critically ill children while considering the inflammatory response and nutritional status. Method A prospective study was conducted in 173 children (median age 34 months) with systemic inflammatory response who had plasma selenium concentrations assessed 48 hours after admission and on the 5th day of ICU stay. The normal reference range was 0.58 μmol/L to 1.6 μmol/L. The outcome variable was ‘low plasma selenium’, which was defined as plasma selenium values below the distribution median during this period. The main explanatory variables were age, malnutrition, sepsis, C-reactive protein (CRP), and clinical severity scores. The data were analyzed using a Binomial Generalized Estimating Equations model, which includes the correlation between admission and 5th day responses. Results Malnutrition and CRP were associated with low plasma selenium. The interaction effect between these two variables was significant. When CRP values were less than or equal to 40 mg/L, malnutrition was associated with low plasma selenium levels (odds ratio (OR) = 3.25, 95% confidence interval (CI) 1.39 to 7.63, P = 0.007; OR = 2.98, 95% CI 1.26 to 7.06, P = 0.013; OR = 2.49, 95% CI 1.01 to 6.17, P = 0.049, for CRP = 10, 20 and 40 mg/L, respectively). This effect decreased as CRP concentrations increased and there was loose significance when CRP values were >40 mg/L. Similarly, the effect of CRP on low plasma selenium was significant for well-nourished patients (OR = 1.13; 95% CI 1.06 to 1.22, P selenium. This interaction should be considered when interpreting plasma concentrations as an index of selenium status in patients with systemic inflammation as well as in the decision

  18. Selenium is a Chemotherapeutic Agent for the Treatment of Prostate Cancer

    National Research Council Canada - National Science Library

    Knox, Susan J

    2005-01-01

    .... In spite of this, little is known about the use of selenium as a cancer therapy. The inorganic form of selenium, selenite, undergoes thiol-dependent reduction to selenide, which supplies selenium for the synthesis of selenoproteins...

  19. Chicken meat nutritional value when feeding red palm oil, palm oil or rendered animal fat in combinations with linseed oil, rapeseed oil and two levels of selenium.

    Science.gov (United States)

    Nyquist, Nicole F; Rødbotten, Rune; Thomassen, Magny; Haug, Anna

    2013-05-09

    Chicken meat nutritional value with regard to fatty acid composition and selenium content depends on the choice of dietary oil and selenium level used in the chickens' feed. The objective of this study was to investigate the effect of replacing commonly used rendered animal fat as a dietary source of saturated fatty acids and soybean oil as a source of unsaturated fatty acids, with palm oil and red palm oil in combinations with rapeseed oil, linseed oil and two levels of selenium enriched yeast on chicken breast meat nutritional value. The study also wished to see whether red palm oil had a cholesterol lowering effect on chicken plasma.204 male, newly hatched broiler chickens were randomly divided into twelve dietary treatment groups, and individually fed one out of six dietary fat combinations combined with either low (0.1 mg Se /kg feed) or high (1 mg Se/kg feed) dietary selenium levels. Linseed oil, independent of accompanying dietary fat source, lead to increased levels of the n-3 EPA, DPA and DHA and reduced levels of the n-6 arachidonic acid (AA). The ratio between AA/EPA was reduced from 19/1 in the soybean oil dietary groups to 1.7/1 in the linseed oil dietary groups. Dietary red palm oil reduced total chicken plasma cholesterol levels. There were no differences between the dietary groups with regard to measured meat antioxidant capacity or sensory evaluation. Chicken meat selenium levels were clearly influenced by dietary selenium levels, but were not influenced by feed fatty acid composition. High dietary selenium level lead to marginally increased n-3 EPA and higher meat fat % in breast muscle but did not influence the other LC PUFA levels. Chicken breast meat nutritional value from the soybean oil and low selenium dietary groups may be regarded as less beneficial compared to the breast meat from the linseed oil and high selenium dietary groups. Replacing rendered animal fat with palm oil and red palm oil had no negative effects on chicken muscle

  20. Internal correction of spectral interferences and mass bias for selenium metabolism studies using enriched stable isotopes in combination with multiple linear regression.

    Science.gov (United States)

    Lunøe, Kristoffer; Martínez-Sierra, Justo Giner; Gammelgaard, Bente; Alonso, J Ignacio García

    2012-03-01

    bias could be accomplished. As a result, the tracer/tracee ratio could be calculated for each selenium-containing species and a time relationship for synthesis and degradation established. Both selenite and selenized yeast labelled with (77)Se were employed for comparative purposes.

  1. Both Selenium Deficiency and Modest Selenium Supplementation Lead to Myocardial Fibrosis in Mice via Effects on Redox-Methylation Balance

    Science.gov (United States)

    Metes-Kosik, Nicole; Luptak, Ivan; DiBello, Patricia M.; Handy, Diane E.; Tang, Shiow-Shih; Zhi, Hui; Qin, Fuzhong; Jacobsen, Donald W.; Loscalzo, Joseph; Joseph, Jacob

    2013-01-01

    Scope Selenium has complex effects in vivo on multiple homeostatic mechanisms such as redox balance, methylation balance, and epigenesis, via its interaction with the methionine-homocysteine cycle. In this study, we examined the hypothesis that selenium status would modulate both redox and methylation balance and thereby modulate myocardial structure and function. Methods and Results We examined the effects of selenium deficient (selenium supplemented (0.5 mg/kg) diets on myocardial histology, biochemistry and function in adult C57/BL6 mice. Selenium deficiency led to reactive myocardial fibrosis and systolic dysfunction accompanied by increased myocardial oxidant stress. Selenium supplementation significantly reduced methylation potential, DNA methyltransferase activity and DNA methylation. In mice fed the supplemented diet, inspite of lower oxidant stress, myocardial matrix gene expression was significantly altered resulting in reactive myocardial fibrosis and diastolic dysfunction in the absence of myocardial hypertrophy. Conclusions Our results indicate that both selenium deficiency and modest selenium supplementation leads to a similar phenotype of abnormal myocardial matrix remodeling and dysfunction in the normal heart. The crucial role selenium plays in maintaining the balance between redox and methylation pathways needs to be taken into account while optimizing selenium status for prevention and treatment of heart failure. PMID:23097236

  2. Enrichment of the African catfish Clarias gariepinus (Burchell) with functional selenium originating from garlic: effect of enrichment period and depuration on total selenium level and sensory properties

    NARCIS (Netherlands)

    Schram, E.; Schelvis-Smit, A.A.M.; Heul, van der J.W.; Luten, J.B.

    2010-01-01

    We wanted to optimize the procedure for the selenium enrichment of farmed African catfish, using garlic as dietary selenium source. In the first experiment we established the relation between the length of the selenium enrichment period and the resulting total selenium level in the fillet of the

  3. Homeostasis of chosen bioelements in organs of rats receiving lithium and/or selenium.

    Science.gov (United States)

    Kiełczykowska, Małgorzata; Musik, Irena; Żelazowska, Renata; Lewandowska, Anna; Kurzepa, Jacek; Kocot, Joanna

    2016-10-01

    Lithium is an essential trace element, widely used in medicine and its application is often long-term. Despite beneficial effects, its administration can lead to severe side effects including hyperparathyroidism, renal and thyroid disorders. The aim of the current study was to evaluate the influence of lithium and/or selenium treatment on magnesium, calcium and silicon levels in rats' organs as well as the possibility of using selenium as an adjuvant in lithium therapy. The study was performed on rats divided into four groups (six animals each): control-treated with saline; Li-treated with Li2CO3 (2.7 mg Li/kg b.w.); Se-treated with Na2SeO3·H2O (0.5 mg Se/kg b.w.); Se + Li-treated simultaneously with Li2CO3 and Na2SeO3·H2O (2.7 mg Li/kg b.w. and of 0.5 mg Se/kg b.w., respectively). The administration was performed in form of water solutions by stomach tube once a day for 3 weeks. In the organs (liver, kidney, brain, spleen, heart, lung and femoral muscle) the concentrations of magnesium, calcium and silicon were determined. Magnesium was increased in liver of Se and Se + Li given rats. Lithium decreased tissue Ca and co-administration of selenium reversed this effect. Silicon was not affected by any treatment. The beneficial effect of selenium on disturbances of calcium homeostasis let suggest that further research on selenium application as an adjuvant in lithium therapy is worth being performed.

  4. Influence of Dietary Selenium Species on Selenoamino Acid Levels in Rainbow Trout.

    Science.gov (United States)

    Godin, Simon; Fontagné-Dicharry, Stéphanie; Bueno, Maïté; Tacon, Philippe; Prabhu, Philip Antony Jesu; Kaushik, Sachi; Médale, Françoise; Bouyssiere, Brice

    2015-07-22

    Two forms of selenium (Se) supplementation of fish feeds were compared in two different basal diets. A 12-week feeding trial was performed with rainbow trout fry using either a plant-based or a fish meal-based diet. Se yeast and selenite were used for Se supplementation. Total Se and Se speciation were determined in both diets and whole body of trout fry using inductively coupled plasma mass spectrometry (ICP MS) and high-performance liquid chromatography (HPLC). The two selenoamino acids, selenomethionine (SeMet) and selenocysteine (SeCys), were determined in whole body of fry after enzymatic digestion using protease type XIV with a prior derivatization step in the case of SeCys. The plant-based basal diet was found to have a much lower total Se than the fish meal-based basal diet with concentrations of 496 and 1222 μg(Se) kg(-1), respectively. Dietary Se yeast had a higher ability to raise whole body Se compared to selenite. SeMet concentration in the fry was increased only in the case of Se yeast supplementation, whereas SeCys levels were similar at the end of the feeding trial for both Se supplemented forms. The results show that the fate of dietary Se in fry is highly dependent on the form brought through supplementation and that a plant-based diet clearly benefits from Se supplementation.

  5. Bioaccumulation and toxicity of selenium during a life-cycle exposure with desert pupfish (Cyprinodon macularius)

    Science.gov (United States)

    Besser, John M.; Brumbaugh, William G.; Papoulias, Diana M.; Ivey, Chris D.; Kunz, James L.; Annis, Mandy; Ingersoll, Christopher G.

    2012-01-01

    Populations of desert pupfish (Cyprinodon macularius; pupfish), a federally-listed endangered species, inhabit irrigation drains in the Imperial Valley agricultural area of southern California. These drains have varying degrees of selenium (Se) contamination of water, sediment, and aquatic biota. Published Se toxicity studies suggest that these levels of Se contamination may pose risk of chronic toxicity to Se-sensitive fish, but until recently there have been no studies of the chronic toxicity of Se to desert pupfish.A life-cycle Se exposure with pupfish was conducted to estimate dietary and tissue thresholds for toxic effects of Se on all life stages. The dietary exposure was based on live oligochaete worms (Lumbriculus variegatus) dosed with Se by a laboratory food chain based on selenized yeast. Oligochaetes readily accumulated Se from mixtures of selenized and control yeasts. The protocol for dosing oligochaetes for pupfish feeding studies included long-term (at least 28 days) feeding of a low-ration of yeast mixtures to large batches of oligochaetes. Oligochaetes were dosed at five Se levels in a 50-percent dilution series. Pupfish were simultaneously fed Se-dosed oligochaetes and exposed to a series of Se concentrations in water (consisting of 85 percent selenate and 15 percent selenite) to produce exposures that were consistent with Se concentrations and speciation in pupfish habitats. The nutritional characteristics of oligochaete diets were consistent across the range of oligochaete Se concentrations tested.The life-cycle exposure started with laboratory-cultured juvenile pupfish that were exposed to Se through sexual maturation and reproduction (150 days; F0 exposure). The Se exposure continued with eggs, larvae, and juveniles produced by Se-exposed parents (79 days; F1 exposure). Selenium exposure (water and diets), Se bioaccumulation (whole-body and eggs), and toxicity endpoints (juvenile and adult survival and growth; egg production and hatching

  6. Metabolic and bioprocess engineering for production of selenized yeast with increased content of seleno-methylselenocysteine

    DEFF Research Database (Denmark)

    Mapelli, Valeria; Hillestrøm, Peter René; Kápolna, Emese

    2011-01-01

    optimized heterologous selenocysteine methyltransferase and endowed with high intracellular levels of S-adenosyl-methionine, was able to accumulate SeMCys at levels higher than commercial selenized yeasts. A fine tuned carbon- and sulfate-limited fed-batch bioprocess was crucial to achieve good yields...... of biomass and SeMCys. Through the coupling of metabolic and bioprocess engineering we achieved a ∼24-fold increase in SeMCys, compared to certified reference material of selenized yeast. In addition, we investigated the interplay between sulfur and selenium metabolism and the possibility that redox...... imbalance occurred along with intracellular accumulation of Se. Collectively, our data show how the combination of metabolic and bioprocess engineering can be used for the production of selenized yeast enriched with beneficial Se-metabolites....

  7. Ecology and biotechnology of selenium-respiring bacteria.

    Science.gov (United States)

    Nancharaiah, Y V; Lens, P N L

    2015-03-01

    In nature, selenium is actively cycled between oxic and anoxic habitats, and this cycle plays an important role in carbon and nitrogen mineralization through bacterial anaerobic respiration. Selenium-respiring bacteria (SeRB) are found in geographically diverse, pristine or contaminated environments and play a pivotal role in the selenium cycle. Unlike its structural analogues oxygen and sulfur, the chalcogen selenium and its microbial cycling have received much less attention by the scientific community. This review focuses on microorganisms that use selenate and selenite as terminal electron acceptors, in parallel to the well-studied sulfate-reducing bacteria. It overviews the significant advancements made in recent years on the role of SeRB in the biological selenium cycle and their ecological role, phylogenetic characterization, and metabolism, as well as selenium biomineralization mechanisms and environmental biotechnological applications. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  8. Production of selenium-enriched milk and dairy products

    Directory of Open Access Journals (Sweden)

    Csapó J.

    2015-01-01

    Full Text Available Until the middle of the last century, selenium was considered to be toxic, but recently it turned out to be a micronutrient with important physiological effects, whose lack impedes the functioning of several enzymes, while in the case of a prolonged deficiency, disease processes can also occur in the body. Hungary belongs to the selenium-deficient regions in Europe; therefore, our aim was to contribute to the improvement of selenium supply of the population through increasing the selenium content of milk and dairy products. A daily supplementation of 1-6 mg organic selenium to the feed of dairy cows increases the selenium content of milk from the value of 18 μg/kg to 94 μg/kg in 8 weeks, decreasing again to the initial value in 6 weeks after stopping the supplementation.

  9. Selenium Recycling in the United States in 2004

    Science.gov (United States)

    George, Micheal W.; Wagner, Lorie A.

    2009-01-01

    The vast majority of selenium consumption in the United States is in dissipative uses, such as alloys, animal feeds, fertilizers, glass decolorizer, and pigments. The nondissipative use as a photoreceptor for xerographic copiers is declining. As a result of a lack of a substantial supply of selenium-containing scrap, there are no longer selenium recycling facilities in the United States. Selenium-containing materials collected for recycling, primarily selenium-containing photocopier drums, are exported for processing in other countries. Of the estimated 350 metric tons (t) of selenium products that went to the U.S. market in 2004, an estimated 300 t went to dissipative uses. An estimated 4 t was recovered from old scrap and exported for recycling.

  10. Effect of a short-term dietary supplementation with phytosterols, red yeast rice or both on lipid pattern in moderately hypercholesterolemic subjects: a three-arm, double-blind, randomized clinical trial.

    Science.gov (United States)

    Cicero, Arrigo F G; Fogacci, Federica; Rosticci, Martina; Parini, Angelo; Giovannini, Marina; Veronesi, Maddalena; D'Addato, Sergio; Borghi, Claudio

    2017-01-01

    Phytosterols and red yeast rice are largely studied cholesterol-lowering nutraceuticals, respectively inhibiting the bowel absorption and liver synthesis of cholesterol. Our aim was to test the effect on lipid profile of phytosterols, red yeast rice and their association. We performed a three parallel arms, double blind, clinical trial randomizing 90 moderately hypercholesterolemic subjects to treatment with phytosterols 800 mg (group 1), red yeast rice standardized to contain 5 mg monacolins from Monascus purpureus (group 2), or both combined nutraceuticals (group 3). After 8 weeks of treatment, in group 1 no significant variation of lipid parameters has been detected. In group 2 a significant reduction (p red yeast rice seems to have additive cholesterol lowering effect, reaching a clinically significant LDL-Cholesterol reduction in mildly hypercholesterolemic patients. ClinicalTrial.gov ID: NCT02603276, Registered 27/08/2015.

  11. [Penicillium-inhibiting yeasts].

    Science.gov (United States)

    Benítez Ahrendts, M R; Carrillo, L

    2004-01-01

    The objective of this work was to establish the in vitro and in vivo inhibition of post-harvest pathogenic moulds by yeasts in order to make a biocontrol product. Post-harvest pathogenic moulds Penicillium digitatum, P. italicum, P. ulaiense, Phyllosticta sp., Galactomyces geotrichum and yeasts belonging to genera Brettanomyces, Candida, Cryptococcus, Kloeckera, Pichia, Rhodotorula were isolated from citrus fruits. Some yeasts strains were also isolated from other sources. The yeasts were identified by their macro and micro-morphology and physiological tests. The in vitro and in vivo activities against P. digitatum or P. ulaiense were different. Candida cantarellii and one strain of Pichia subpelliculosa produced a significant reduction of the lesion area caused by the pathogenic moulds P. digitatum and P. ulaiense, and could be used in a biocontrol product formulation.

  12. Toxicity of Selenium, Weathered and Aged in Soil, to the Collembolan Folsomia candida

    Science.gov (United States)

    2016-07-01

    Highway , Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be...ecotoxicological benchmarks for developing the ecological soil screening levels (Eco-SSLs) for risk assessments of contaminated soils. For this study, we...developing soil invertebrate-based Eco-SSL for Se. 15. SUBJECT TERMS Ecological soil screening level (Eco-SSL) Selenium Selenite Natural soil Folsomia

  13. Determination of Selenium Toxicity for Survival and Reproduction of Enchytraeid Worms in a Sandy Loam Soil

    Science.gov (United States)

    2016-07-01

    Jefferson Davis Highway , Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no...ecotoxicological benchmarks for developing the ecological soil screening levels (Eco-SSLs) for risk assessments of contaminated soils. For the present study, we...invertebrate-based Eco-SSL for Se. 15. SUBJECT TERMS Ecological soil screening level (Eco-SSL) Selenium Natural soil Enchytraeus crypticus Selenate

  14. Nitrile Metabolizing Yeasts

    Science.gov (United States)

    Bhalla, Tek Chand; Sharma, Monica; Sharma, Nitya Nand

    Nitriles and amides are widely distributed in the biotic and abiotic components of our ecosystem. Nitrile form an important group of organic compounds which find their applications in the synthesis of a large number of compounds used as/in pharmaceutical, cosmetics, plastics, dyes, etc>. Nitriles are mainly hydro-lyzed to corresponding amide/acid in organic chemistry. Industrial and agricultural activities have also lead to release of nitriles and amides into the environment and some of them pose threat to human health. Biocatalysis and biotransformations are increasingly replacing chemical routes of synthesis in organic chemistry as a part of ‘green chemistry’. Nitrile metabolizing organisms or enzymes thus has assumed greater significance in all these years to convert nitriles to amides/ acids. The nitrile metabolizing enzymes are widely present in bacteria, fungi and yeasts. Yeasts metabolize nitriles through nitrilase and/or nitrile hydratase and amidase enzymes. Only few yeasts have been reported to possess aldoxime dehydratase. More than sixty nitrile metabolizing yeast strains have been hither to isolated from cyanide treatment bioreactor, fermented foods and soil. Most of the yeasts contain nitrile hydratase-amidase system for metabolizing nitriles. Transformations of nitriles to amides/acids have been carried out with free and immobilized yeast cells. The nitrilases of Torulopsis candida>and Exophiala oligosperma>R1 are enantioselec-tive and regiospecific respectively. Geotrichum>sp. JR1 grows in the presence of 2M acetonitrile and may have potential for application in bioremediation of nitrile contaminated soil/water. The nitrilase of E. oligosperma>R1 being active at low pH (3-6) has shown promise for the hydroxy acids. Immobilized yeast cells hydrolyze some additional nitriles in comparison to free cells. It is expected that more focus in future will be on purification, characterization, cloning, expression and immobilization of nitrile metabolizing

  15. Selenium Poisoning of Wildlife and Western Agriculture: Cause and Effect

    Energy Technology Data Exchange (ETDEWEB)

    Korte, N.E.

    2000-02-01

    This project examined the hypothesis that selenium contamination is not the principal cause of the decline of endemic fish species in the Upper Colorado Basin. Activities employed to test this hypothesis included a reconnaissance of locations altered by recent road construction, a re-interpretation of available literature regarding selenium toxicity, and the interpretation of unpublished data obtained from the Upper Colorado Basin Fish Recovery Program. The project demonstrates that most of the evidence implicating selenium is circumstantial.

  16. Health risk assessment of environmental selenium: Emerging evidence and challenges

    OpenAIRE

    Vinceti,Marco; Filippini, Tommaso; Cilloni, Silvia; Bargellini, Annalisa; Vergoni, Anna Valeria; Tsatsakis, Aristides; Ferrante, Margherita

    2017-01-01

    New data have been accumulated in the scientific literature in recent years which allow a more adequate risk assessment of selenium with reference to human health. This new evidence comes from environmental studies, carried out in populations characterized by abnormally high or low selenium intakes, and from high-quality and large randomized controlled trials with selenium recently carried out in the US and in other countries. These trials have consistently shown no beneficial effect on cance...

  17. Forces in yeast flocculation

    Science.gov (United States)

    El-Kirat-Chatel, Sofiane; Beaussart, Audrey; Vincent, Stéphane P.; Abellán Flos, Marta; Hols, Pascal; Lipke, Peter N.; Dufrêne, Yves F.

    2015-01-01

    In the baker's yeast Saccharomyces cerevisiae, cell-cell adhesion (``flocculation'') is conferred by a family of lectin-like proteins known as the flocculin (Flo) proteins. Knowledge of the adhesive and mechanical properties of flocculins is important for understanding the mechanisms of yeast adhesion, and may help controlling yeast behaviour in biotechnology. We use single-molecule and single-cell atomic force microscopy (AFM) to explore the nanoscale forces engaged in yeast flocculation, focusing on the role of Flo1 as a prototype of flocculins. Using AFM tips labelled with mannose, we detect single flocculins on Flo1-expressing cells, showing they are widely exposed on the cell surface. When subjected to force, individual Flo1 proteins display two distinct force responses, i.e. weak lectin binding forces and strong unfolding forces reflecting the force-induced extension of hydrophobic tandem repeats. We demonstrate that cell-cell adhesion bonds also involve multiple weak lectin interactions together with strong unfolding forces, both associated with Flo1 molecules. Single-molecule and single-cell data correlate with microscale cell adhesion behaviour, suggesting strongly that Flo1 mechanics is critical for yeast flocculation. These results favour a model in which not only weak lectin-sugar interactions are involved in yeast flocculation but also strong hydrophobic interactions resulting from protein unfolding.

  18. Effects of selenium on mallard duck reproduction and immune function

    Energy Technology Data Exchange (ETDEWEB)

    Whiteley, P.L.; Yuill, T.M.; Fairbrother, A.

    1989-11-01

    Selenium from irrigation drain water and coal-fired power stations is a significant environmental contaminant in some regions of the USA. The objectives were to examine whether selenium-exposed waterfowl had altered immune function, disease resistance, or reproduction. Pairs of adult mallards were exposed for 95-99 days on streams with sodium selenite-treated water at 10 and 30 ppb, or on untreated streams. Selenium biomagnified through the food chain to the ducks. Disease resistance was decreased in ducklings hatched on the streams and challenged with duck hepatitis virus 1 (DHV1) when 15-days old. Liver selenium concentrations for these ducklings on the 10 and 30 ppb streams was 3.6 and 7.6 ppm dry weight, respectively. Mortality of ducklings purchased when 7-days old, exposed to selenium for 14 days, and challenged when 22-days old was not affected. However, their selenium exposure was lower (liver selenium 4.1 ppm dry weight for the 30 ppb stream). Five parameters of immune function were measured in adult ducks. Phagocytosis of killed Pasteurella multocida by blood heterophils and monocytes, and blood monocyte concentrations were higher in adult males following 84 days exposure to 30 ppb selenium. Their liver selenium concentrations were 11.1 ppm dry weight after 95-99 days exposure.

  19. Teratogenic effects of selenium in natural populations of freshwater fish.

    Science.gov (United States)

    Lemly, A D

    1993-10-01

    The prevalence of abnormalities and associated tissue selenium residues were assessed for the fish population of Belews Lake, North Carolina, and two reference lakes in 1975, 1978, 1982, and 1992. Teratogenic defects identified included lordosis, kyphosis, scoliosis, and head, mouth, and fin deformities. Many fish exhibited multiple malformations and some were grossly deformed and distorted in appearance. Other abnormalities observed were edema, exophthalmus, and cataracts. Whole-body tissue residues of selenium in the fishes of Belews Lake were up to 130 times those in the reference lakes and the incidence of abnormalities was some 7 to 70 times greater. Teratogenic defects increased as selenium levels rose between 1975 and 1982 and fell with declining selenium levels between 1982 and 1992 as selenium inputs into Belews Lake were curtailed. The relationship between selenium residues and prevalence of malformations approximated an exponential function (R2 = 0.881, P selenium and 0-70% deformities. This relationship could be useful in evaluating the role of teratogenic effects in warm-water fish populations suspected of having selenium-related reproductive failure. Unique conditions may have existed in Belews Lake which led to the high frequency and persistence of deformities in juvenile and adult fish. In other, less-contaminated locations competition and predation may eliminate malformed individuals in all but the larval life stage. Teratogenesis could be an important, but easily overlooked phenomenon contributing to fishery reproductive failure in selenium-contaminated aquatic habitats.

  20. Conceptual Model for Selenium Cycling in the Great Salt Lake

    Science.gov (United States)

    Johnson, W. P.; Conover, M. R.; Wurtsbaugh, W. A.; Adams, J.

    2006-12-01

    The conceptual model for Selenium cycling in the Great Salt Lake was developed to guide investigations in support of determining an open water selenium standard for the Great Salt Lake. The motivation to determine this particular selenium standard derives from public concern for a plan to allow disposal of reverse osmosis (RO) concentrate in the GSL, which would contain elevated concentrations of major and trace elements, including selenium. The development of an open water standard for selenium requires a working knowledge of the biological significance of existing selenium concentrations in the Great Salt Lake, as well as a working understanding of the likely changes of these concentrations over time given existing and proposed loads to the system. This working knowledge" is being represented in a conceptual model that accounts for selenium in various stocks" in the system (e.g. water, sediment, biota) and the flow" of selenium between stocks (e.g., precipitation and settling, volatilization, bioconcentration). It illustrates the critical pathway of selenium in the Great Salt Lake from water, to microorganisms, to brine shrimp and brine flies, to birds, and to their eggs. It also addresses the complexity of the GSL system: a) Spatially diverse, being comprised by four distinct bays and two layers, with major differences in salinity among their waters. b) Temporally dynamic, due to seasonal and inter-annual variations in runoff. The conceptual model is presently descriptive, but will serve as the basis for a semi-quantitative model that will be fed by data accumulated during subsequent investigations.

  1. Volatile Selenium Flux in the Great Salt Lake

    Science.gov (United States)

    Diaz, X.; Johnson, W. P.

    2006-12-01

    Volatilization of selenium has been proven to be the major source of selenium vapor from oceans and estuaries and it may be the major mechanism of permanent selenium removal from the Great Salt Lake (other than brine shrimp harvest). However, the volatilization flux of selenium from the Great Salt Lake has not been previously measured due to challenges of analysis in this hyper-saline environment. This work presents results from recent field studies examining the spatial distribution of volatile selenium (geographical and with depth) in the South Arm (main body) of the Great Salt Lake. The analyses involved collection of volatile selenium in a cryo-focusing trap system via sparging with helium. The cryo-trapped volatile selenium was digested with nitric acid and analyzed by ICP-MS. The results show concentrations of volatile selenium that are much greater than values reported for marine estuaries and oceans. Volatile selenium flux to the atmosphere was determined using mass transport equations corrected to simulate the highly saline environment of the South Arm of the Great Salt Lake.

  2. Hazard assessment of selenium to endangered razorback suckers (Xyrauchen texanus)

    Science.gov (United States)

    Hamilton, S.J.; Holley, K.M.; Buhl, K.J.

    2002-01-01

    A hazard assessment was conducted based on information derived from two reproduction studies conducted with endangered razorback suckers (Xyrauchen texanus) at three sites near Grand Junction, CO, USA. Selenium contamination of the upper and lower Colorado River basin has been documented in water, sediment, and biota in studies by US Department of the Interior agencies and academia. Concern has been raised that this selenium contamination may be adversely affecting endangered fish in the upper Colorado River basin. The reproduction studies with razorback suckers revealed that adults readily accumulated selenium in various tissues including eggs, and that 4.6 μg/g of selenium in food organisms caused increased mortality of larvae. The selenium hazard assessment protocol resulted in a moderate hazard at the Horsethief site and high hazards at the Adobe Creek and North Pond sites. The selenium hazard assessment was considered conservative because an on-site toxicity test with razorback sucker larvae using 4.6 μg/g selenium in zooplankton caused nearly complete mortality, in spite of the moderate hazard at Horsethief. Using the margin of uncertainty ratio also suggested a high hazard for effects on razorback suckers from selenium exposure. Both assessment approaches suggested that selenium in the upper Colorado River basin adversely affects the reproductive success of razorback suckers.

  3. Absorption and retention of selenium from shrimps in man

    DEFF Research Database (Denmark)

    Bugel, S. H.; Sandstrom, B.; Larsen, Erik Huusfeldt

    2001-01-01

    This study was undertaken to evaluate the bioavailability of selenium in shrimps, a possible good source of selenium, by measurements of the absorption and retention of selenium and the effects on plasma selenium concentration and glutathione peroxidase activity. Twelve healthy young subjects (9F...... of the study, after 2, 4, and 6 weeks. The selenium intake increased from 39.4 +/- 15.3 mug/d to 127 +/- 5.5 mug/d with the addition of shrimps. The apparent absorption of selenium from shrimps was 83 +/- 4%, Faecal and urinary selenium excretion was 32.5 +/- 17.0 mug/d and 21.2 +/- 9.0 mug/d, re spectively...... and the total retention of selenium was 3.1 +/- 1.1 mg. Plasma selenium concentrations were 95.2 +/- 9.7 mug/L and 101.5 +/- 9.7 mug/L before and after six weeks of shrimp intake, respectively (p...

  4. Selenium and Human Health: Witnessing a Copernican Revolution?

    Science.gov (United States)

    Jablonska, Ewa; Vinceti, Marco

    2015-01-01

    In humans, selenium was hypothesized to lower the risk of several chronic diseases, mainly due to the antioxidant activity of selenium-containing proteins. Recent epidemiologic and laboratory studies, however, are changing our perception of the biological effects of this nutritionally essential trace element. We reviewed the most recent epidemiologic and biochemical literature on selenium, synthesizing the findings from these studies into a unifying view. Randomized trials have shown that selenium did not protect against cancer and other chronic diseases, but even increased the risk of specific neoplasms such as advanced prostate cancer and skin cancer, in addition to type 2 diabetes. Biochemical studies indicate that selenium may exert a broad pattern of toxic effects at unexpectedly low concentrations. Furthermore, its upregulation of antioxidant proteins (selenium-dependent and selenium-independent) may be a manifestation of self-induced oxidative stress. In conclusion, toxic effects of selenium species occur at lower concentrations than previously believed. Those effects may include a large range of proteomic changes and adverse health effects in humans. Since the effects of environmental exposure to this element on human health still remain partially unknown, but are potentially serious, the toxicity of selenium exposure should be further investigated and considered as a public health priority.

  5. Is selenium supplementation in autoimmune thyroid diseases justified?

    Science.gov (United States)

    Winther, Kristian H; Bonnema, Steen J; Hegedüs, Laszlo

    2017-10-01

    This review provides an appraisal of recent evidence for or against selenium supplementation in patients with autoimmune thyroid diseases, and discusses possible effect mechanisms. Epidemiological data suggest an increased prevalence of autoimmune thyroid diseases under conditions of low dietary selenium intake. Two systematic reviews have evaluated controlled trials among patients with autoimmune thyroiditis and report that selenium supplementation decreases circulating thyroid autoantibodies. The immunomodulatory effects of selenium might involve reducing proinflammatory cytokine release. However, clinically relevant effects of selenium supplementation, including improvement in quality of life, are more elusive. In Graves' disease, some, but not all, trials indicate that adjuvant selenium supplementation enhances the restoration of biochemical euthyroidism, and might benefit patients with mild Graves' orbitopathy. The use of selenium supplementation as adjuvant therapy to standard thyroid medication may be widespread, but a growing body of evidence yields equivocal results. The available evidence from trials does not support routine selenium supplementation in the standard treatment of patients with autoimmune thyroiditis or Graves' disease. However, correction of moderate to severe selenium deficiency may offer benefits in preventing, as well as treating, these disorders. Molecular mechanisms have been proposed, but further studies are needed.

  6. Selenium Administration Attenuates 5-Flurouracil-Induced Intestinal Mucositis.

    Science.gov (United States)

    Lee, Jae Min; Chun, Hoon Jai; Choi, Hyuk Soon; Kim, Eun Sun; Seo, Yeon Seok; Jeen, Yoon Tae; Lee, Hong Sik; Um, Soon Ho; Kim, Chul Hwan; Sul, Donggeun

    2017-01-01

    Chemotherapy-induced mucositis is mediated by the release of proinflammatory cytokines and reactive oxygen species. Selenium has several metabolic functions, including the protection of membrane lipids and macromolecules against oxidative damage. However, to date, there is little evidence on the effect of trace elements on intestinal mucositis after chemotherapy. This study investigated the protective effect of selenium against chemotherapy-induced mucositis in rats. Twenty-four 9-wk-old female Wistar rats were randomized to 4 groups: control, selenium, 5-fluorouracil (5-FU), and 5-FU plus selenium. Mucositis was induced by a single dose of 5-FU (400 mg/kg BW) via intraperitoneal injection, and selenium was administered by a single intraperitoneal dose of sodium selenite (0.2 mg/kg BW). Diarrhea and weight loss after 5-FU administration were attenuated by selenium treatment. The mean villus height in the 5-FU plus selenium group was significantly taller than rats administered with 5-FU alone, but not significantly different compared to the control group. Interleukin (IL)-1β and tumor necrosis factor (TNF)-α mRNA expression were significantly lower in the 5-FU plus selenium group than in the 5-FU only group (IL-1β, P selenium protects the mucosa during chemotherapy via its anti-inflammatory effects and its suppression of cytotoxic cytokine production.

  7. Ecological Importance of Insects in Selenium Biogenic Cycling

    Directory of Open Access Journals (Sweden)

    Nadezhda Golubkina

    2014-01-01

    Full Text Available Selenium is an essential trace element for animal and human beings. Despite the importance of insects in most ecosystems and their significant contribution to the biological cycling of trace elements due to high abundance, population productivity, and diverse ecosystem functions, surprisingly little information is available on selenium bioaccumulation by these arthropods. This review considers selenium essentiality and toxicity to insects as well as insects’ contribution to selenium trophic transfer through the food chains. Data on Se accumulation by insects of the Dniester River Valley with no anthropogenic Se loading reveal typically low Se content in necrophagous insects compared to predators and herbivores and seasonal variations in Se accumulation.

  8. Determination of arsenic and selenium by hydride generation and headspace solid phase microextraction coupled with optical emission spectrometry

    Science.gov (United States)

    Tyburska, Anna; Jankowski, Krzysztof; Rodzik, Agnieszka

    2011-07-01

    A hydride generation headspace solid phase microextraction technique has been developed in combination with optical emission spectrometry for determination of total arsenic and selenium. Hydrides were generated in a 10 mL volume septum-sealed vial and subsequently collected onto a polydimethylsiloxane/Carboxen solid phase microextraction fiber from the headspace of sample solution. After completion of the sorption, the fiber was transferred into a thermal desorption unit and the analytes were vaporized and directly introduced into argon inductively coupled plasma or helium microwave induced plasma radiation source. Experimental conditions of hydride formation reaction as well as sorption and desorption of analytes have been optimized showing the significant effect of the type of the solid phase microextraction fiber coating, the sorption time and hydrochloric acid concentration of the sample solution on analytical characteristics of the method developed. The limits of detection of arsenic and selenium were 0.1 and 0.8 ng mL - 1 , respectively. The limit of detection of selenium could be improved further using biosorption with baker's yeast Saccharomyces cerevisiae for analyte preconcentration. The technique was applied for the determination of total As and Se in real samples.

  9. Determination of arsenic and selenium by hydride generation and headspace solid phase microextraction coupled with optical emission spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Tyburska, Anna; Jankowski, Krzysztof, E-mail: kj@ch.pw.edu.pl; Rodzik, Agnieszka

    2011-07-15

    A hydride generation headspace solid phase microextraction technique has been developed in combination with optical emission spectrometry for determination of total arsenic and selenium. Hydrides were generated in a 10 mL volume septum-sealed vial and subsequently collected onto a polydimethylsiloxane/Carboxen solid phase microextraction fiber from the headspace of sample solution. After completion of the sorption, the fiber was transferred into a thermal desorption unit and the analytes were vaporized and directly introduced into argon inductively coupled plasma or helium microwave induced plasma radiation source. Experimental conditions of hydride formation reaction as well as sorption and desorption of analytes have been optimized showing the significant effect of the type of the solid phase microextraction fiber coating, the sorption time and hydrochloric acid concentration of the sample solution on analytical characteristics of the method developed. The limits of detection of arsenic and selenium were 0.1 and 0.8 ng mL{sup -1}, respectively. The limit of detection of selenium could be improved further using biosorption with baker's yeast Saccharomyces cerevisiae for analyte preconcentration. The technique was applied for the determination of total As and Se in real samples.

  10. Toxicity and oxidative stress of different forms of organic selenium and dietary protein in mallard ducklings

    Science.gov (United States)

    Hoffman, D.J.; Heinz, G.H.; LeCaptain, L.J.; Eisemann, J.D.; Pendleton, G.W.

    1996-01-01

    Concentrations of over 100 ppm (mg/kg) selenium (Se) have been found in aquatic plants and insects associated with irrigation drainwater and toxicity to fish and wildlife. Composition of diet for wild ducklings may vary in selenium-contaminated environments. Earlier studies have compared toxicities and oxidative stress of Se as selenite to those of seleno-DL-methionine (DL) in mallards (Anas platyrhynchos). This study compares DL, seleno-L-methionine (L), selenized yeast (Y) and selenized wheat (W). Day-old mallard ducklings received an untreated diet (controls) containing 75% wheat (22% protein) or the same diet containing 15 or 30 ppm Se in the above forms except for 30 ppm Se as W. After 2 weeks blood and liver samples were collected for biochemical assays and Se analysis. All forms of selenium caused significant increases in plasma and hepatic glutathione peroxidase activities. Se as L at 30 ppm in the diet was the most toxic form, resulting in high mortality (64%) and impaired growth (>50%) in survivors and the greatest increase in ratio of oxidized to reduced hepatic glutathione (GSH). Se as both L and DL decreased the concentrations of hepatic GSH and total thiols. Se as Y accumulated the least in liver (approximately 50% of other forms) and had less effect on GSH and total thiols. In a second experiment, in which the basal diet was a commercial duck feed (22 % protein), survival was not affected by 30 ppm Se as DL, L, or Y and oxidative effects on GSH metabolism were less pronounced than with the wheat diet.

  11. Dietary selenium increases vitamin E contents of egg yolk and chicken meat.

    Science.gov (United States)

    Skrivan, M; Marounek, M; Dlouhá, G; Sevcíková, S

    2008-07-01

    1. The influence of different forms of dietary selenium (Se) on vitamin E (alpha-tocopherol) and Se contents of egg yolk and chicken meat was investigated. 2. Eggs were collected from laying hens subjected to 4 different dietary treatments after 24 weeks of age. Treatments compared the effects of inorganic Se supplementation (selenite) to those of organic (Se-enriched yeast, Se-enriched alga Chlorella) supplements. In a second experiment the effect of the above organic dietary Se supplementation on the alpha-tocopherol contents of meat from broiler chickens was evaluated. 3. Dietary Se supplementation increased the alpha-tocopherol content of egg yolks from 297 mg/kg dry matter in treatment without supplementation to 311 mg/kg when selenium was supplemented as selenite, and to 370-375 mg/kg when organic supplements were used. The Se and alpha-tocopherol contents of breast and thigh meat in broilers were significantly increased by organic dietary Se supplementation. 4. The inclusion of organic dietary Se sources in the diets of laying hens and broilers would enhance the nutritional value (vitamin E and Se contents) of products (eggs and meat) for human consumption.

  12. The interplay between sulphur and selenium metabolism influences the intracellular redox balance in Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Mapelli, Valeria; Hillestrøm, Peter René; Patil, Kalpesh

    2012-01-01

    Selenium (Se) is an essential element for most eukaryotic organisms, including humans. The balance between Se toxicity and its beneficial effects is very delicate. It has been demonstrated that a diet enriched with Se has cancer prevention potential in humans. The most popular commercial Se...... supplementation is selenized yeast, which is produced in a fermentation process using an inorganic source of Se. Here, we show that the uptake of Se, Se toxic effects and intracellular Se-metabolite profile are largely influenced by the level of sulphur source supplied during the fermentation. A Yap1-dependent...... on the central carbon metabolism. The observed increase in glycerol production rate, concomitant with the inhibition of ethanol formation in the presence of Se, can be ascribed to the occurrence of redox imbalance that triggers glycerol biosynthesis to replenish the pool of NAD+....

  13. Evolutionary biology through the lens of budding yeast comparative genomics.

    Science.gov (United States)

    Marsit, Souhir; Leducq, Jean-Baptiste; Durand, Éléonore; Marchant, Axelle; Filteau, Marie; Landry, Christian R

    2017-10-01

    The budding yeast Saccharomyces cerevisiae is a highly advanced model system for studying genetics, cell biology and systems biology. Over the past decade, the application of high-throughput sequencing technologies to this species has contributed to this yeast also becoming an important model for evolutionary genomics. Indeed, comparative genomic analyses of laboratory, wild and domesticated yeast populations are providing unprecedented detail about many of the processes that govern evolution, including long-term processes, such as reproductive isolation and speciation, and short-term processes, such as adaptation to natural and domestication-related environments.

  14. Genetic polymorphisms that affect selenium status and response to selenium supplementation in United Kingdom pregnant women1

    Science.gov (United States)

    Mao, Jinyuan; Vanderlelie, Jessica J; Perkins, Anthony V; Redman, Christopher WG; Ahmadi, Kourosh R; Rayman, Margaret P

    2016-01-01

    Background: Low selenium status in pregnancy has been associated with a number of adverse conditions. In nonpregnant populations, the selenium status or response to supplementation has been associated with polymorphisms in dimethylglycine dehydrogenase (DMGDH), selenoprotein P (SEPP1) and the glutathione peroxidases [cytosolic glutathione peroxidase (GPx1) and phospholipid glutathione peroxidase (GPx4)]. Objective: We hypothesized that, in pregnant women, these candidate polymorphisms would be associated with selenium status in early pregnancy, its longitudinal change, and the interindividual response to selenium supplementation at 60 μg/d. Design: With the use of stored samples and data from the United Kingdom Selenium in Pregnancy Intervention (SPRINT) study in 227 pregnant women, we carried out genetic-association studies, testing for associations between selenium status, its longitudinal change, and response to supplementation and common genetic variation in DMGDH (rs921943), SEPP1 (rs3877899 and rs7579), GPx1 (rs1050450) and GPx4 (rs713041). Selenium status was represented by the concentration of whole-blood selenium at 12 and 35 wk of gestation, the concentration of toenail selenium at 16 wk of gestation, and plasma glutathione peroxidase (GPx3) activity at 12 and 35 wk of gestation. Results: Our results showed that DMGDH rs921943 was significantly associated with the whole-blood selenium concentration at 12 wk of gestation (P = 0.032), which explained ≤2.0% of the variance. This association was replicated with the use of toenail selenium (P = 0.043). In unsupplemented women, SEPP1 rs3877899 was significantly associated with the percentage change in whole-blood selenium from 12 to 35 wk of gestation (P = 0.005), which explained 8% of the variance. In supplemented women, SEPP1 rs3877899 was significantly associated with the percentage change in GPx3 activity from 12 to 35 wk of gestation (P = 0.01), which explained 5.3% of the variance. Selenium status was

  15. Sponge-supported synthesis of colloidal selenium nanospheres

    Science.gov (United States)

    Ahmed, Snober; Brockgreitens, John; Xu, Ke; Abbas, Abdennour

    2016-11-01

    With increasing biomedical and engineering applications of selenium nanospheres (SeNS), new efficient methods are needed for the synthesis and long-term preservation of these nanomaterials. Currently, SeNS are mostly produced through the biosynthesis route using microorganisms or by using wet chemical reduction, both of which have several limitations in terms of nanoparticle size, yield, production time and long-term stability of the nanoparticles. Here, we introduce a novel approach for rapid synthesis and long-term preservation of SeNS on a solid microporous support by combining a mild hydrothermal process with chemical reduction. By using a natural sponge as a solid three-dimensional matrix for nanoparticle growth, we have synthesized highly monodisperse spherical nanoparticles with a wide size range (10-1000 nm) and extremely high yield in a relatively short period of time (1 h). Additionally, the synthesized SeNS can be stored and retrieved whenever needed by simply washing the sponge in water. Keeping the nanospheres in the support offers remarkable long-term stability as particles left on the sponge preserve their morphological and colloidal characteristics even after eight months of storage. Furthermore, this work reveals that SeNS can be used for efficient mercury capture from contaminated waters with a record-breaking mercury removal capacity of 1900 mg g-1.

  16. Improvement of Selenium Status of Pasture Crops

    DEFF Research Database (Denmark)

    Nielsen, Gunnar Gissel

    1984-01-01

    Selenium was applied to pasture crops in a field experiment (1) by foliar application of 10 g Se/ha as selenite in the spring, (2) or by 5 g Se/ha in the spring plus 5 g in early August, (3) as selenite-enriched calcium ammonium nitrate (CAN) at 4 g Se/ha after each cut, and (4) as 4 g Se after...

  17. Selenoprotein P is the major selenium transport protein in mouse milk.

    Directory of Open Access Journals (Sweden)

    Kristina E Hill

    Full Text Available Selenium is transferred from the mouse dam to its neonate via milk. Milk contains selenium in selenoprotein form as selenoprotein P (Sepp1 and glutathione peroxidase-3 (Gpx3 as well as in non-specific protein form as selenomethionine. Selenium is also present in milk in uncharacterized small-molecule form. We eliminated selenomethionine from the mice in these experiments by feeding a diet that contained sodium selenite as the source of selenium. Selenium-replete dams with deletion of Sepp1 or Gpx3 were studied to assess the effects of these genes on selenium transfer to the neonate. Sepp1 knockout caused a drop in milk selenium to 27% of the value in wild-type milk and a drop in selenium acquisition by the neonates to 35%. In addition to decreasing milk selenium by eliminating Sepp1, deletion of Sepp1 causes a decline in whole-body selenium, which likely also contributes to the decreased transfer of selenium to the neonate. Deletion of Gpx3 did not decrease milk selenium content or neonate selenium acquisition by measurable amounts. Thus, when the dam is fed selenium-adequate diet (0.25 mg selenium/kg diet, milk Sepp1 transfers a large amount of selenium to neonates but the transfer of selenium by Gpx3 is below detection by our methods.

  18. Impact of Selenium Supplementation on Growth and Selenium Accumulation on Spinach (Spinacia oleracea L. Plants

    Directory of Open Access Journals (Sweden)

    Azadeh SAFFARYAZDI

    2012-11-01

    Full Text Available Selenium (Se has been proved to be an essential element for humans and animals. However, less is known about its effects on plants. A hydroponic experiment was carried out to investigate the effects of selenium on growth, selenium accumulation and some physiological characteristics of spinach (Spinacia oleracea L. cv. �Missouri� plants. Plants were grown in Hoagland nutrient solution amended with sodium selenite at 0 (control, 1, 2, 4, 6 and 10 mg.L-1 for 28 days. Growth parameters like shoot and root fresh weight, shoot and root dry weight, total dry weight, shoot and root length increased by 17, 15, 38, 19, 18 and 34 percent in response to the lowest concentration of Se (1 mg L-1, respectively over control. However, application of higher Se concentrations reduced these parameters as compared to control. Selenium up to 1 mg L-1 enhanced the levels of chlorophyll a and chlorophyll b by 87 and 165 percent, respectively, while higher levels of Se exert toxic effects. Total phenolic compounds in leaves increased directly by increasing the level of Se and plants treated with 10 mg. L-1 Se had the highest values. Selenium, sodium and calcium content increased, while potassium content decreased, by increasing selenium treatments. The highest amounts of Se in shoots (3.89 mg g-1 DW and roots (4.27 mg g-1 DW were obtained for the highest concentration of Se (10 mg L-1. The present results suggested the beneficial effects of Se on spinach growth and also its contribute ion to improving the nutritional value of spinach for livestock and human nutrition.

  19. Impact of Selenium Supplementation on Growth and Selenium Accumulation on Spinach (Spinacia oleracea L. Plants

    Directory of Open Access Journals (Sweden)

    Azadeh SAFFARYAZDI

    2012-11-01

    Full Text Available Selenium (Se has been proved to be an essential element for humans and animals. However, less is known about its effects on plants. A hydroponic experiment was carried out to investigate the effects of selenium on growth, selenium accumulation and some physiological characteristics of spinach (Spinacia oleracea L. cv. Missouri plants. Plants were grown in Hoagland nutrient solution amended with sodium selenite at 0 (control, 1, 2, 4, 6 and 10 mg.L-1 for 28 days. Growth parameters like shoot and root fresh weight, shoot and root dry weight, total dry weight, shoot and root length increased by 17, 15, 38, 19, 18 and 34 percent in response to the lowest concentration of Se (1 mg L-1, respectively over control. However, application of higher Se concentrations reduced these parameters as compared to control. Selenium up to 1 mg L-1 enhanced the levels of chlorophyll a and chlorophyll b by 87 and 165 percent, respectively, while higher levels of Se exert toxic effects. Total phenolic compounds in leaves increased directly by increasing the level of Se and plants treated with 10 mg. L-1 Se had the highest values. Selenium, sodium and calcium content increased, while potassium content decreased, by increasing selenium treatments. The highest amounts of Se in shoots (3.89 mg g-1 DW and roots (4.27 mg g-1 DW were obtained for the highest concentration of Se (10 mg L-1. The present results suggested the beneficial effects of Se on spinach growth and also its contribute ion to improving the nutritional value of spinach for livestock and human nutrition.

  20. Biofortification and phytoremediation of selenium in China.

    Science.gov (United States)

    Wu, Zhilin; Bañuelos, Gary S; Lin, Zhi-Qing; Liu, Ying; Yuan, Linxi; Yin, Xuebin; Li, Miao

    2015-01-01

    Selenium (Se) is an essential trace element for humans and animals but at high concentrations, Se becomes toxic to organisms due to Se replacing sulfur in proteins. Selenium biofortification is an agricultural process that increases the accumulation of Se in crops, through plant breeding, genetic engineering, or use of Se fertilizers. Selenium phytoremediation is a green biotechnology to clean up Se-contaminated environments, primarily through phytoextraction and phytovolatilization. By integrating Se phytoremediation and biofortification technologies, Se-enriched plant materials harvested from Se phytoremediation can be used as Se-enriched green manures or other supplementary sources of Se for producing Se-biofortified agricultural products. Earlier studies primarily aimed at enhancing efficacy of phytoremediation and biofortification of Se based on natural variation in progenitor or identification of unique plant species. In this review, we discuss promising approaches to improve biofortification and phytoremediation of Se using knowledge acquired from model crops. We also explored the feasibility of applying biotechnologies such as inoculation of microbial strains for improving the efficiency of biofortification and phytoremediation of Se. The key research and practical challenges that remain in improving biofortification and phytoremediation of Se have been highlighted, and the future development and uses of Se-biofortified agricultural products in China has also been discussed.

  1. Zinc and selenium nutritional status in vegetarians.

    Science.gov (United States)

    de Bortoli, Maritsa Carla; Cozzolino, Silvia Maria Franciscato

    2009-03-01

    A vegetarian diet may have beneficial effects on human health, however when it is not well-balanced may be deficient in some nutrients, as minerals for example. The aim of the present study was to assess the nutritional status of zinc and selenium in vegetarians in the city of São Paulo. A cross-sectional study was performed, and the inclusion criteria were age > or = 18 years, both gender, no use of food or pharmaceutical supplements. Thirty vegetarian, of both genders, mean age of 27 years and 4.5 years of vegetarianism had performed the study, and their mean BMI was 21.5. Zinc plasma concentration was 71 and 62.5 microg/dL for men and women and erythrocyte concentration was 37 microg/gHb for both genders. Selenium concentration was 73.5 and 77.3 microg/L in plasma and 51.4 and 66.9 microg/L in erythrocytes for men and women, respectively. These biochemical values show that, according to the references, selenium blood levels are adequate and zinc concentration in erythrocytes is deficient in the studied population. For this reason, vegetarians should be constantly assessed and receive nutritional support to reduce the effects of inadequate zinc status.

  2. Selenium in soil–plant–food systems

    Directory of Open Access Journals (Sweden)

    Garousi F.

    2017-10-01

    Full Text Available Humans and animals require a multitude of nutrients in order to have a properly functioning body for purposes of growth, development and metabolism. Plant-based foods have represented one of the most important nutrient sources in human diet since the beginning of mankind. But nowadays the amount of arable land is being reduced and much of the natural resources already in use show signs of degradation. Also, staple crops (i.e. plants that constitute the main food in the diets of people in developing countries, e.g. wheat, rice, maize, and cassava regrettably contain low amounts of micronutrients, making them insufficient to meet the minimum daily requirements. Shortages in mineral micronutrients, including iron (Fe, zinc (Zn, selenium (Se, and iodine (I, are affecting more than half of the world’s population. In this case, it is fundamental to improve strategies that let us make plant foods more efficient and with higher micronutrient amounts and bioavailability concerning their edible textures. In this regard, in this review paper, we tried to summarize selenium availability and its application in the soil, plant and food systems to understand the place of selenium in plant-based foods.

  3. Selenium accumulation and metabolism in algae.

    Science.gov (United States)

    Schiavon, Michela; Ertani, Andrea; Parrasia, Sofia; Vecchia, Francesca Dalla

    2017-08-01

    Selenium (Se) is an intriguing element because it is metabolically required by a variety of organisms, but it may induce toxicity at high doses. Algae primarily absorb selenium in the form of selenate or selenite using mechanisms similar to those reported in plants. However, while Se is needed by several species of microalgae, the essentiality of this element for plants has not been established yet. The study of Se uptake and accumulation strategies in micro- and macro-algae is of pivotal importance, as they represent potential vectors for Se movement in aquatic environments and Se at high levels may affect their growth causing a reduction in primary production. Some microalgae exhibit the capacity of efficiently converting Se to less harmful volatile compounds as a strategy to cope with Se toxicity. Therefore, they play a crucial role in Se-cycling through the ecosystem. On the other side, micro- or macro-algae enriched in Se may be used in Se biofortification programs aimed to improve Se content in human diet via supplementation of valuable food. Indeed, some organic forms of selenium (selenomethionine and methylselenocysteine) are known to act as anticarcinogenic compounds and exert a broad spectrum of beneficial effects in humans and other mammals. Here, we want to give an overview of the developments in the current understanding of Se uptake, accumulation and metabolism in algae, discussing potential ecotoxicological implications and nutritional aspects. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Krypton ion implantation effect on selenium nanowires

    Science.gov (United States)

    Panchal, Suresh; Chauhan, R. P.

    2017-08-01

    Among the rapidly progressing interdisciplinary areas of physics, chemistry, material science etc. ion induced modifications of materials is one such evolving field. It has been realized in recent years that a material, in the form of an accelerated ion beam, embedded into a target specimen offers a most productive tool for transforming its properties in a controlled manner. In semiconductors particularly, where the transport behavior is determined by very small concentrations of certain impurities, implantation of ions may bring considerable changes. The present work is based on the study of the effect of krypton ion implantation on selenium nanowires. Selenium nanowires of diameter 80 nm were synthesized by template assisted electro deposition technique. Implantation of krypton ions was done at Inter University Accelerator Centre (IUAC), New Delhi, India. The effect of implantation on structural, electrical and optical properties of selenium nanowires was investigated. XRD analysis of pristine and implanted nanowires shows no shifting in the peak position but there is a variation in the relative intensity with fluence. UV-Visible spectroscopy shows the decrease in the optical band gap with fluence. PL spectra showed emission peak at higher wavelength. A substantial rise in the current was observed from I-V measurements, after implantation and with the increase in fluence. The increase in current conduction may be due to the increase in the current carriers.

  5. Yeasts associated with Manteca.

    Science.gov (United States)

    Suzzi, Giovanna; Schirone, Maria; Martuscelli, Maria; Gatti, Monica; Fornasari, Maria Emanuela; Neviani, Erasmo

    2003-04-01

    Manteca is a traditional milk product of southern Italy produced from whey deriving from Caciocavallo Podolico cheese-making. This study was undertaken to obtain more information about the microbiological properties of this product and particularly about the presence, metabolic activities, and technological significance of the different yeast species naturally occurring in Manteca. High numbers of yeasts were counted after 7 days ripening (10(4)-10(5) cfu g(-1)) and then decreased to 10(2) at the end. A total of 179 isolates were identified and studied for their phenotypic and genotypic characteristics. The most frequently encountered species were Trichosporon asahii (45), Candida parapsilosis (33), Rhodotorula mucilaginosa (32), Candida inconspicua (29). Some of these yeasts showed lipolytic activity (32 strains) and proteolytic activity (29 strains), NaCl resistance up to 10% and growth up to 45 degrees C (42 strains). Biogenic amines were formed by proteolytic strains, in particular phenylethylamine, putrescine and spermidine. Spermidine was produced by all the yeasts tested in this work, but only Trichosporon produced a great quantity of this compound. Histamine was not detectable. Caseinolytic activity was common to almost all strains, corresponding to the ability to efficiently split off amino-terminal amino acids. The highest and most constant activity expressed by all species was X-prolyl-dipeptidyl aminopeptidase. The findings suggest that the presence of yeasts may play a significant role in justifying interactions with lactic acid bacteria, and consequently with their metabolic activity in the definition of the peculiar characteristics of Manteca cheese.

  6. Yeast genome sequencing:

    DEFF Research Database (Denmark)

    Piskur, Jure; Langkjær, Rikke Breinhold

    2004-01-01

    they are short and degenerate and occupy different positions. Comparative genomics helps to understand the origin of yeasts and points out crucial molecular events in yeast evolutionary history, such as whole-genome duplication and horizontal gene transfer(s). In addition, the accumulating sequence data provide...... that the minimum number of genes from each species that need to be compared to produce a reliable phylogeny is about 20. Yeast has also become an attractive model to study speciation in eukaryotes, especially to understand molecular mechanisms behind the establishment of reproductive isolation. Comparison...... of closely related species helps in gene annotation and to answer how many genes there really are within the genomes. Analysis of non-coding regions among closely related species has provided an example of how to determine novel gene regulatory sequences, which were previously difficult to analyse because...

  7. Lower plasma levels of selenium and glutathione in smear- positive ...

    African Journals Online (AJOL)

    admin

    Abstract. Objective: The objective of this study was to investigate selenium and glutathione levels in pulmonary tuberculosis patients and controls in Malawi. Methods: The case-control study included 19 patients and 15 apparently healthy controls for whom, levels of selenium and glutathione were measured. Results: The ...

  8. Copper and selenium supplementation of ewes gnazing on pastures ...

    African Journals Online (AJOL)

    Influence of copper and selenium supplementation in SA Mutton. Merino ewes, kept on pastures with low copper ... plasma copper, pregnancy, selenium supplementation,. Low copper concentrations are frequently ... very weak at birth, their mortality rate was high and growth rate poor (Van Niekerk & Van Niekerk, 1989c).

  9. Lentils (Lens culinaris L.) as a source of dietary selenium

    Science.gov (United States)

    The chapter discusses the nutritional value of lentils, with a focus on factors affecting lentils as a source of dietary selenium. It addresses the chemical nature of lentil-selenium, pointing out that more than 90% is present in organic compounds which are generally well absorbed by humans. The se...

  10. Accurate determination of selenium and iron in erythrocytes from ...

    African Journals Online (AJOL)

    Accurate determination of selenium and iron in erythrocytes from Nigeria subjects using INAA. JO Ojo, Jan Kucera. Abstract. Levels of two essential elements playing crucial roles in erythrocyte's structure and functions, iron and selenium, have been carefully determined in 36 erythrocyte samples drawn from two healthy ...

  11. Relationship between soil contents and plasma levels of selenium ...

    African Journals Online (AJOL)

    The soil contents of trace elements selenium, chromium and manganese were measured to determine their impact on the plasma levels of 160 healthy adult Nigerians in five different experimental locations in Cross River and Akwa Ibom States, South - South Nigeria. The mean (±SD) soil selenium, chromium and ...

  12. Influence of different soaking times with selenium on growth ...

    African Journals Online (AJOL)

    Low temperature (LT) is one of the most important factors limiting the growth, development and distribution of wheat plants in temperate regions. Selenium often acts as an antioxidant in plants and this study hypothesize that selenium application can partly alleviate LT-induced oxidative stress and negative impacts of LT on ...

  13. Mercury and selenium in wild and experimental seals

    NARCIS (Netherlands)

    Ven, van de W.S.M.; Koeman, J.H.; Svenson, A.

    1979-01-01

    This paper describes the tissue distribution of inorganic mercury, organic mercury selenium in Dutch and British seals as well as in seals which were dosed with methylmercury under experimental conditions. In the experimental animals, a time-related increase of both mercury and selenium was found in

  14. Importance of selenium status in patients with chronic heart failure

    Directory of Open Access Journals (Sweden)

    Nicole Ebner

    2015-02-01

    Full Text Available Overactivity of the immune system may be a worthwhile therapeutic target for implementing prognostic improvements. Therefore the impact of lipopolysaccharide (LPS desensitization on survival may help in the development of novel therapies. An understanding of the pathophysiology of the trace element selenium may complement such approaches, as recent data suggest that inflammatory responses are selenium-dependent.

  15. The selenium status of grazing herbivores in different regions of ...

    African Journals Online (AJOL)

    Unknown

    Although a substantial amount of information is available on the selenium status of grazing animals in southern Africa, this information has not been mapped to give a clear view of the situation at a glance. In this presentation data available to the author have been used to produce a map of the selenium status of grazing ...

  16. Copper and selenium supplementation of ewes grazing on pastures ...

    African Journals Online (AJOL)

    Influence of copper and selenium supplementationi n SA Mutton Merino ewes, kept on pastures with low copper and selenium concentrations, was investigated. Ewes which came into oestrus and conceived during March to April, were found to have concentrations of plasma copper of 60 to 80 pg /dl. Inadequare copper ...

  17. Enrichment of African catfish with functional selenium originating from garlic

    NARCIS (Netherlands)

    Schram, E.; Pedrero, Z.; Camara, C.; Heul, van der J.W.; Luten, J.B.

    2008-01-01

    We wanted to create functional seafood with high concentrations of organic selenium (seleno-methyl-selenocysteine and ¿-glutamyl-seleno-methyl-selenocysteine) with anti-carcinogenic properties for human consumers. Garlic containing high concentrations of these organic selenium compounds was used as

  18. Selenium enrichment pattern in flowering Chinese cabbage, cabbage and asparagus

    NARCIS (Netherlands)

    Mo, H.Z.; Yang Zhu, Yang; Zhang, M.

    2006-01-01

    CONCLUSIONS - Within a certain range, selenium accumulation in three studied vegetables was lineally correlated with spraying concentration. However, a too high concentration caused the reduction of vegetable output and damage in quality. - Twice spraying with lower concentration of selenium was a

  19. 21 CFR 524.2101 - Selenium disulfide suspension.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Selenium disulfide suspension. 524.2101 Section 524.2101 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... § 524.2101 Selenium disulfide suspension. (a) Specifications. The product contains 0.9-percent weight in...

  20. 21 CFR 520.2100 - Selenium, vitamin E capsules.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Selenium, vitamin E capsules. 520.2100 Section 520.2100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2100 Selenium, vitamin...

  1. Zinc and Selenium levels in Motor Mechanics, Paints Sprayers ...

    African Journals Online (AJOL)

    Zinc and Selenium levels in Motor Mechanics, Paints Sprayers, Smokers, Lubricant Workers and Battery Workers Exposed to Lead in Nnewi, South Eastern Nigeria. ... Blood lead, zinc and selenium levels were determined in both exposed and control subjects. Results: The result shows that there was a significant increase ...

  2. Acute selenium toxicity associated with a dietary supplement.

    Science.gov (United States)

    MacFarquhar, Jennifer K; Broussard, Danielle L; Melstrom, Paul; Hutchinson, Richard; Wolkin, Amy; Martin, Colleen; Burk, Raymond F; Dunn, John R; Green, Alice L; Hammond, Roberta; Schaffner, William; Jones, Timothy F

    2010-02-08

    Selenium is an element necessary for normal cellular function, but it can have toxic effects at high doses. We investigated an outbreak of acute selenium poisoning. A case was defined as the onset of symptoms of selenium toxicity in a person within 2 weeks after ingesting a dietary supplement manufactured by "Company A," purchased after January 1, 2008. We conducted case finding, administered initial and 90-day follow-up questionnaires to affected persons, and obtained laboratory data where available. The source of the outbreak was identified as a liquid dietary supplement that contained 200 times the labeled concentration of selenium. Of 201 cases identified in 10 states, 1 person was hospitalized. The median estimated dose of selenium consumed was 41 749 microg/d (recommended dietary allowance is 55 microg/d). Frequently reported symptoms included diarrhea (78%), fatigue (75%), hair loss (72%), joint pain (70%), nail discoloration or brittleness (61%), and nausea (58%). Symptoms persisting 90 days or longer included fingernail discoloration and loss (52%), fatigue (35%), and hair loss (29%). The mean initial serum selenium concentration of 8 patients was 751 microg/L (reference range, selenium concentration of 7 patients was 166 microg/24 h (reference range, selenium in a liquid dietary supplement resulted in a widespread outbreak. Had the manufacturers been held to standards used in the pharmaceutical industry, it may have been prevented.

  3. Selenium induces cholinergic motor neuron degeneration in Caenorhabditis elegans.

    Science.gov (United States)

    Estevez, Annette O; Mueller, Catherine L; Morgan, Kathleen L; Szewczyk, Nathaniel J; Teece, Luke; Miranda-Vizuete, Antonio; Estevez, Miguel

    2012-10-01

    Selenium is an essential micronutrient required for cellular antioxidant systems, yet at higher doses it induces oxidative stress. Additionally, in vertebrates environmental exposures to toxic levels of selenium can cause paralysis and death. Here we show that selenium-induced oxidative stress leads to decreased cholinergic signaling and degeneration of cholinergic neurons required for movement and egg-laying in Caenorhabditis elegans. Exposure to high levels of selenium leads to proteolysis of a soluble muscle protein through mechanisms suppressible by two pharmacological agents, levamisole and aldicarb which enhance cholinergic signaling in muscle. In addition, animals with reduction-of-function mutations in genes encoding post-synaptic levamisole-sensitive acetylcholine receptor subunits or the vesicular acetylcholine transporter developed impaired forward movement faster during selenium-exposure than normal animals, again confirming that selenium reduces cholinergic signaling. Finally, the antioxidant reduced glutathione, inhibits selenium-induced reductions in egg-laying through a cellular protective mechanism dependent on the C. elegans glutaredoxin, GLRX-21. These studies provide evidence that the environmental toxicant selenium induces neurodegeneration of cholinergic neurons through depletion of glutathione, a mechanism linked to the neuropathology of Alzheimer's disease, amyotrophic lateral sclerosis, and Parkinson's disease. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. The influence of zinc and selenium on some biochemical responses ...

    African Journals Online (AJOL)

    Water deficit cowpea sample treated with selenium once weekly (WOS) returned back to full turgor after 6 days of rehydration with water. Rehydration caused significant reductions in MDA levels and antioxidant enzymes activities. The use of antioxidant chemicals particularly selenium is therefore recommended in this study ...

  5. Aquatic selenium pollution is a global environmental safety issue

    Science.gov (United States)

    A. Dennis Lemly

    2004-01-01

    Selenium pollution is a worldwide phenomenon and is associated with a broad spectrum of human activities, ranging from the most basic agricultural practices to the most high-tech industrial processes. Consequently, selenium contamination of aquatic habitats can take place in urban, suburban, and rural settings alike--from mountains to plains, from deserts to...

  6. Genetics of Yeasts

    Science.gov (United States)

    Querol, Amparo; Fernández-Espinar, M. Teresa; Belloch, Carmela

    The use of yeasts in biotechnology processes dates back to ancient days. Before 7000 BC, beer was produced in Sumeria. Wine was made in Assyria in 3500 BC, and ancient Rome had over 250 bakeries, which were making leavened bread by 100 BC. And milk has been made into Kefyr and Koumiss in Asia for many centuries (Demain, Phaff, & Kurtzman, 1999). However, the importance of yeast in the food and beverage industries was only realized about 1860, when their role in food manufacturing became evident.

  7. Recent Microextraction Techniques for Determination and Chemical Speciation of Selenium

    Directory of Open Access Journals (Sweden)

    Ibrahim Ahmed S. A.

    2017-05-01

    Full Text Available Research designed to improve extraction has led to the development of microextraction techniques (ME, which involve simple, low cost, and effective preconcentrationof analytes in various matrices. This review is concerned with the principles and theoretical background of ME, as well as the development of applications for selenium analysis during the period from 2008 to 2016. Among all ME, dispersive liquid-liquid microextraction was found to be most favorable for selenium. On the other hand, atomic absorption spectrometry was the most frequently used instrumentation. Selenium ME have rarely been coupled to spectrophotometry and X-ray spectrophotometry methods, and there is no published application of ME with electrochemical techniques. We strongly support the idea of using a double preconcentration process, which consists of microextraction prior to preconcentration, followed by selenium determination using cathodic stripping voltammetry (ME-CSV. More attention should focus on the development of accurate, precise, and green methods for selenium analysis.

  8. L-arabinose fermenting yeast

    Science.gov (United States)

    Zhang, Min; Singh, Arjun; Knoshaug, Eric; Franden, Mary Ann; Jarvis, Eric; Suominen, Pirkko

    2010-12-07

    An L-arabinose utilizing yeast strain is provided for the production of ethanol by introducing and expressing bacterial araA, araB and araD genes. L-arabinose transporters are also introduced into the yeast to enhance the uptake of arabinose. The yeast carries additional genomic mutations enabling it to consume L-arabinose, even as the only carbon source, and to produce ethanol. Methods of producing ethanol include utilizing these modified yeast strains. ##STR00001##

  9. Selenium fertilization on lentil (Lens culinaris Medikus) grain yield, seed selenium concentration, and antioxidant activity

    Science.gov (United States)

    Selenium (Se) is an essential element for mammals but has not been considered as an essential element for higher plants. Lentil (Lens culinaris Medik.) is a cool season food legume rich in protein and a range of micronutrients including minerals (iron and zinc), folates, and carotenoids. The objecti...

  10. Total selenium and selenium species in irrigation drain inflows to the Salton Sea, California, October 2008 and January 2009

    Science.gov (United States)

    May, Thomas W.; Walther, Michael J.; Saiki, Michael K.; Brumbaugh, William G.

    2009-01-01

    This report presents the results for two sampling periods (October 2008 and January 2009) during a 4-year monitoring program to characterize selenium concentrations in selected irrigation drains flowing into the Salton Sea, California. Total selenium, selenium species (dissolved selenite, selenate, organoselenium), and total suspended solids were determined in water samples. Total selenium also was determined in water column particulates and in sediment, detritus, and biota that included algae, plankton, midge larvae (family, Chironomidae), and two fish species (western mosquitofish, Gambusia affinis, and sailfin molly, Poecilia latipinna). In addition, sediments were analyzed for percent total organic carbon and particle size. Mean total selenium concentrations in water for both sampling periods ranged from 1.00 to 33.6 micrograms per liter, predominately as selenate, which is typical of waters where selenium is leached out of selenium-containing marine shales and associated soils under alkaline and oxidizing conditions. Total selenium concentrations (micrograms per gram dry weight) ranged as follows: algae, 1.52 to 8.26; plankton, 0.79 to 3.66; midges, 2.68 to 50.6; fish, 3.09 to 30.4; detritus, 1.78 to 58.0; and sediment, 0.42 to 10.0.

  11. Total selenium and selenium species in irrigation drain inflows to the Salton Sea, California, October 2007 and January 2008

    Science.gov (United States)

    May, Thomas W.; Walther, Michael J.; Saiki, Michael K.; Brumbaugh, William G.

    2008-01-01

    This report presents the results for two sampling periods (October 2007 and January 2008) during a 4-year monitoring program to characterize selenium concentrations in selected irrigation drains flowing into the Salton Sea, California. Total selenium, selenium species (selenite, selenate, organoselenium), and total suspended solids were determined in water samples, and total selenium was determined in sediment, detritus, and biota that included algae, plankton, midge larvae (family, Chironomidae), and two fish species?western mosquitofish (Gambusia affinis) and sailfin molly (Poecilia latipinna). In addition, sediments were analyzed for percent total organic carbon and particle size. Mean total selenium concentrations in water for both sampling periods ranged from 0.97 to 64.5 micrograms per liter, predominately as selenate, which is typical of waters where selenium is leached out of selenium-containing marine shales and associated soils under alkaline and oxidizing conditions. Total selenium concentrations (micrograms per gram dry weight) ranged as follows: algae, 0.95 to 5.99; plankton, 0.15 to 19.3; midges, 1.39 to 15.4; fish, 3.71 to 25.1; detritus, 0.85 to 21.7; sediment, 0.32 to 7.28.

  12. Total selenium and selenium species in irrigation drain inflows to the Salton Sea, California, April and July 2008

    Science.gov (United States)

    May, Thomas W.; Walther, Michael J.; Saiki, Michael K.; Brumbaugh, William G.

    2009-01-01

    This report presents the results for two sampling periods (April 2008 and July 2008) during a 4-year monitoring program to characterize selenium concentrations in selected irrigation drains flowing into the Salton Sea, California. Total selenium, selenium species (dissolved selenite, selenate, organoselenium), and total suspended solids were determined in water samples and total selenium was determined in water column particulates and in sediment, detritus, and biota that included algae, plankton, midge larvae (family, Chironomidae), and two fish species - western mosquitofish (Gambusia affinis) and sailfin molly (Poecilia latipinna). In addition, sediments were analyzed for percent total organic carbon and particle size. Mean total selenium concentrations in water for both sampling periods ranged from 1.93 to 44.2 micrograms per liter, predominately as selenate, which is typical of waters where selenium is leached out of selenium-containing marine shales and associated soils under alkaline and oxidizing conditions. Total selenium concentrations (micrograms per gram dry weight) ranged as follows: algae, 0.75 to 3.39; plankton, 0.88 to 4.03; midges, 2.52 to 44.3; fish, 3.37 to 18.9; detritus, 1.11 to 13.6; sediment, 0.11 to 8.93.

  13. Selenium and Lung Cancer: A Systematic Review and Meta Analysis

    Science.gov (United States)

    Fritz, Heidi; Kennedy, Deborah; Fergusson, Dean; Fernandes, Rochelle; Cooley, Kieran; Seely, Andrew; Sagar, Stephen; Wong, Raimond; Seely, Dugald

    2011-01-01

    Background Selenium is a natural health product widely used in the treatment and prevention of lung cancers, but large chemoprevention trials have yielded conflicting results. We conducted a systematic review of selenium for lung cancers, and assessed potential interactions with conventional therapies. Methods and Findings Two independent reviewers searched six databases from inception to March 2009 for evidence pertaining to the safety and efficacy of selenium for lung cancers. Pubmed and EMBASE were searched to October 2009 for evidence on interactions with chemo- or radiation-therapy. In the efficacy analysis there were nine reports of five RCTs and two biomarker-based studies, 29 reports of 26 observational studies, and 41 preclinical studies. Fifteen human studies, one case report, and 36 preclinical studies were included in the interactions analysis. Based on available evidence, there appears to be a different chemopreventive effect dependent on baseline selenium status, such that selenium supplementation may reduce risk of lung cancers in populations with lower baseline selenium status (serumselenium (≥121.6 ng/mL). Pooling data from two trials yielded no impact to odds of lung cancer, OR 0.93 (95% confidence interval 0.61–1.43); other cancers that were the primary endpoints of these trials, OR 1.51 (95%CI 0.70–3.24); and all-cause-death, OR 0.93 (95%CI 0.79–1.10). In the treatment of lung cancers, selenium may reduce cisplatin-induced nephrotoxicity and side effects associated with radiation therapy. Conclusions Selenium may be effective for lung cancer prevention among individuals with lower selenium status, but at present should not be used as a general strategy for lung cancer prevention. Although promising, more evidence on the ability of selenium to reduce cisplatin and radiation therapy toxicity is required to ensure that therapeutic efficacy is maintained before any broad clinical recommendations can be made in this context. PMID:22073154

  14. EFFECT OF DIETARY SODIUM SELENITE AND SE-ENRICHED YEAST ON EGG-SHELL QUALITATIVE PARAMETERS OF LAYING HENS EGGS

    Directory of Open Access Journals (Sweden)

    Henrieta ARPÁŠOVÁ

    2010-10-01

    Full Text Available The experiment was designed to investigate the effects of feed supplementation with selenite or selenized yeast on eggs quality of laying hens. Hens of laying breed Isabrown were randomly divided at the day of hatching into 4 groups (n=12 and fed ad libitum for 9 months on diets which differed only in amounts or forms of selenium supplemented. Hens were fed from 1st day by standard feed mixture. Control group get only native dose of selenium (0.1 mg/kg naturally presented in feed mixtures. First experimental group get selenium addition 0.4 mg/kg in a form of sodium selenite, second one the same dose of 0.4 mg/kg but in organic form of Se-yeast. The diet for the fourth group was supplemented with Se-yeast at Se dose 0.9 mg/kg DM. The both doses of organic selenium had significantly (P<0.05 beneficial influence on the egg weight (g±SD (60.45±3.87a; 60.81±5.63a; 62.41±3.72b; 62.15±3.16b. Significantly lower values of egg shell weight and egg shell ratio were found out in experimental group with sodium selenite only. The significantly lower egg shell strength (N/cm2 was in the experimental groups with supplementation of Se in both forms. Average egg shell thickness (μm were not significantly affected (P>0.05 by the supplementation of Se into the feed mixture for laying hens.

  15. The risk assessment of selenium exposure from food in the Slovak Republic

    OpenAIRE

    Ursinyova, Monika

    2012-01-01

    Selenium is a ubiquitous essential trace element originated from natural and anthropogenic sources.  Effects of selenium on human health are ranging from protective to toxic (acute or chronic selenosis). Toxicity depends on the form of selenium in a compound and its bioavailability. Selenium occurs naturally in food and is worldwide approved as an additive into food and food supplements. The existing studies point out that the levels of selenium in food and the status of Slovak population are...

  16. Recombinant wine yeasts

    OpenAIRE

    González García, Ramón; González Ramos, Daniel

    2008-01-01

    The invention relates to a method for obtaining strains that secrete a higher concentration of mannoproteins to the medium, a Saccharomyces cerevisiae yeast strain deposited at the Spanish Type Culture Collection (CECT) as CECT 13012, and to the uses of said strains.

  17. SELENIUM SUBSTITUTION – EFFECT ON THYROID FUNCTION

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    Milica Pešić

    2015-03-01

    Full Text Available The understanding of the essential role of selenium (Se in thyroid hormone synthesis, metabolism and action, as well as normal thyroid function, increased during the past decades. The thyroid gland is among the human tissues with the highest Se content per mas unit, similar to other endocrine organs and brain. Biological actions of Se are mediated, in most cases, through the expression of at least 30 selenoproteins coded by 25 selenoprotein genes in the human. Via the selenoproteins, selenium can influence the cell function through antioxidant activites, modifying redox status and thyroid hormone synthesis and metabolism. Selenoproteins iodothyronine deiodinases are present in most tissues and have a role to increase the production of bioactive tri-iodothyronine. Futhermore, Se has been shown to be important in the regulation of immune function. Se deficiency is accompained by the loss of immune competence. The links between Se deficiency, altered immune function and inflamation have prompted studies in humans to examine if Se suplementation can modify auto-antibodies production in patients with chronic autoimmune thyroiditis. Until now, several randomised prospective clinical trials have been performed in patients with established chronic autoimmune thyrioditis. The clinical endpoint of each study was the decrease in TPO antibodies concentration after 3-12 months of treatment. Ussualy, the dosage of daily Se supplementation was 200µg. Selenium suplemetation had no significant effect on the concentration of TSH or thyroid hormone concentrations. These studies indicate that Se treatment result in reduced inflammatory activity, but it does not cure chronc autoimmune process.

  18. Preparation and antioxidant properties of selenium nanoparticles-loaded chitosan microspheres.

    Science.gov (United States)

    Bai, Kaikai; Hong, Bihong; He, Jianlin; Hong, Zhuan; Tan, Ran

    2017-01-01

    Selenium nanoparticles (SeNPs), as a special form of selenium (Se) supplement, have attracted worldwide attention due to their favorable properties and unique bioactivities. Herein, an eco-friendly and economic way to prepare stable SeNPs is introduced. SeNPs were synthesized in aqueous chitosan (CTS) and then embedded into CTS microspheres by spray-drying, forming selenium nanoparticles-loaded chitosan microspheres (SeNPs-M). The physicochemical properties including morphology, elemental state, size distribution and surface potential were investigated. Institute of Cancer Research mice were used as model animal to evaluate the bioactivities of SeNPs-M. Trigonal-phase SeNPs of ~35 nm were synthesized, and SeNPs-M physically embedding those SeNPs were successfully prepared. Amazingly, acute toxicity test indicated that SeNPs-M were much safer than selenite in terms of Se dose, with a LD50 of around 18-fold of that of selenite. In addition, SeNPs-M possessed powerful antioxidant activities, as evidenced by a dramatic increase of both Se retention and the levels of glutathione peroxidase, superoxide dismutase and catalase. The design of SeNPs-M can offer a new way for further development of SeNPs with a higher efficacy and better biosafety. Thus, SeNPs-M may be a potential candidate for further evaluation as an Se supplement with antioxidant properties and be used against Se deficiency in animals and human beings.

  19. Proteolytic activities in yeast.

    Science.gov (United States)

    Saheki, T; Holzer, H

    1975-03-28

    Studies on the mechanism and time course of the activation of proteinases A (EC 3.4.23.8), B (EC 3.4.22.9) and C (EC 3.4.12.--) in crude yeast extracts at pH 5.1 and 25 degrees C showed that the increase in proteinase B activity is paralleled with the disappearance of proteinase B inhibitor. Addition of purified proteinase A to fresh crude extracts accelerates the inactivation of the proteinase B inhibitor and the appearance of maximal activities of proteinases B and C. The decrease of proteinase B inhibitor activity and the increase of proteinase B activity are markedly retarded by the addition of pepstatin. Because 10-minus 7 M pepstatin completely inhibits proteinase A without affecting proteinase B activity, this is another indication for the role of proteinase A during the activation of proteinase B. Whereas extracts of yeast grown on minimal medium reached maximal activation of proteinases B and C after 20 h of incubation at pH 5.1 and 25 degrees C, extracts of yeast grown on complete medium had to be incubated for about 100 h. In the latter case, the addition of proteinas A results in maximal activation of proteinases B and C and disappearance of proteinase B inhibitor activity only after 10--20 h of incubation. With the optimal conditions, the maximal activities of proteinases A, B and C, as well as of the proteinase B inhibitor, were determined in crude extracts of yeast that had been grown batchwise for different lengths of time either on minimal or on complete medium. Upon incubation, all three proteinases were activated by several times their initial activity. This reflects the existence of proteolytically degradable inhibitors of the three proteinases and together with the above mentioned observations it demonstrates that the "activation" of yeast proteinases A, B and C upon incubation results from the proteolytic digestion of inhibitors rather than from activation of inactive zymogens by limited proteolysis.

  20. L-arabinose fermenting yeast

    Science.gov (United States)

    Zhang, Min; Singh, Arjun; Suominen, Pirkko; Knoshaug, Eric; Franden, Mary Ann; Jarvis, Eric

    2013-02-12

    An L-arabinose utilizing yeast strain is provided for the production of ethanol by introducing and expressing bacterial araA, araB and araD genes. L-arabinose transporters are also introduced into the yeast to enhance the uptake of arabinose. The yeast carries additional genomic mutations enabling it to consume L-arabinose, even as the only carbon source, and to produce ethanol. A yeast strain engineered to metabolize arabinose through a novel pathway is also disclosed. Methods of producing ethanol include utilizing these modified yeast strains.

  1. Lithium as a prooxidant? A possible protective role of selenium - in vitro study.

    Science.gov (United States)

    Musik, Irena; Kiełczykowska, Małgorzata; Rajtar, Barbara; Świątek, Łukasz; Polz-Dacewicz, Małgorzata; Kocot, Joanna

    2017-09-21

    Lithium is used in medicine but its application may cause diverse side effects. Selenium has been found to show protective properties against negative influence of different harmful factors. This study was aimed at evaluating the influence of non-toxic dose of lithium on antioxidant parameters in FaDu (ATCC HTB-43) and Vero (ECACC No. 84113001) cell lines as well as the possible protective effect of non-toxic concentration of sodium selenite. The cells were subjected to 0.17 mmol/L of Li2CO3 and/or 2.9 µmol/L of Na2SeO3 · 5H2O for Vero as well as 0.47 mmol/L of Li2CO3 and/or 3.0 µmol/L of Na2SeO3 · 5H2O for FaDu cells. The incubation was continued for the subsequent 72 h. In the cells total antioxidant status (TAS) values, activities of antioxidant enzymes - superoxide dismutase (SOD) and glutathione peroxidase (GPx) as well as the reduced glutathione concentration (GSH) were determined. In Vero cells lithium decreased all studied parameters, particularly GPx. Selenium co-treatment showed a distinct protective effect. In FaDu cells the similar effect was observed only in case of GSH. The results point to differences in action of lithium and selenium in physiological and pathological state. As long-term lithium therapy is applied in psychiatric patients the results regarding Vero line let suggest that selenium might be considered as an adjuvant alleviating side effects of Li-treatment.

  2. Transcriptomic responses of cancerous and noncancerous human colon cells to sulforaphane and selenium.

    Science.gov (United States)

    Constantinescu, Simona; Hecht, Katrin; Sobotzki, Nadine; Erzinger, Melanie M; Bovet, Cédric; Shay, Jerry W; Wollscheid, Bernd; Sturla, Shana J; Marra, Giancarlo; Beerenwinkel, Niko

    2014-03-17

    Diets enriched with bioactive food components trigger molecular changes in cells that may contribute to either health-promoting or adverse effects. Recent technological advances in high-throughput data generation allow for observing systems-wide molecular responses to cellular perturbations with nontoxic and dietary-relevant doses while considering the intrinsic differences between cancerous and noncancerous cells. In this chemical profile, we compared molecular responses of the colon cancer cell line HT29 and a noncancerous colon epithelial cell line (HCEC) to two widely encountered food components, sulforaphane and selenium. We conducted this comparison by generating new transcriptome data by microarray gene-expression profiling, analyzing them statistically on the single gene, network, and functional pathway levels, and integrating them with protein expression data. Sulforaphane and selenium, at doses that did not inhibit the growth of the tested cells, induced or repressed the transcription of a limited number of genes in a manner distinctly dependent on the chemical and the cell type. The genes that most strongly responded in cancer cells were observed after treatment with sulforaphane and were members of the aldo-keto reductase (AKR) superfamily. These genes were in high agreement in terms of fold change with their corresponding proteins (correlation coefficient r(2) = 0.98, p = 0.01). Conversely, selenium had little influence on the cancer cells. In contrast, in noncancerous cells, selenium induced numerous genes involved in apoptotic, angiogenic, or tumor proliferation pathways, whereas the influence of sulforaphane was very limited. These findings contribute to defining the significance of cell type in interpreting human cellular transcriptome-level responses to exposures to natural components of the diet.

  3. Yeast ecology of Kombucha fermentation.

    Science.gov (United States)

    Teoh, Ai Leng; Heard, Gillian; Cox, Julian

    2004-09-01

    Kombucha is a traditional fermentation of sweetened tea, involving a symbiosis of yeast species and acetic acid bacteria. Despite reports of different yeast species being associated with the fermentation, little is known of the quantitative ecology of yeasts in Kombucha. Using oxytetracycline-supplemented malt extract agar, yeasts were isolated from four commercially available Kombucha products and identified using conventional biochemical and physiological tests. During the fermentation of each of the four products, yeasts were enumerated from both the cellulosic pellicle and liquor of the Kombucha. The number and diversity of species varied between products, but included Brettanomyces bruxellensis, Candida stellata, Schizosaccharomyces pombe, Torulaspora delbrueckii and Zygosaccharomyces bailii. While these yeast species are known to occur in Kombucha, the enumeration of each species present throughout fermentation of each of the four Kombucha cultures demonstrated for the first time the dynamic nature of the yeast ecology. Kombucha fermentation is, in general, initiated by osmotolerant species, succeeded and ultimately dominated by acid-tolerant species.

  4. Vitamin E and selenium supplementation and risk of prostate cancer in the Vitamins and lifestyle (VITAL) study cohort.

    Science.gov (United States)

    Peters, Ulrike; Littman, Alyson J; Kristal, Alan R; Patterson, Ruth E; Potter, John D; White, Emily

    2008-02-01

    Vitamin E and selenium are promising nutrients for the prevention of prostate cancer, and both are currently being tested in a large randomized trial for prostate cancer. However, results are not expected for at least 6 years. We aimed to investigate the association of vitamin E and selenium supplementation with prostate cancer in the VITamins And Lifestyle (VITAL) study, a cohort study specifically designed to examine supplement use and future cancer risk. In a prospective design, 35,242 men recruited between 2000 and 2002 from western Washington State completed a questionnaire, including detailed questions about vitamin E and selenium supplement intake during the past 10 years from brand-specific multivitamins and single supplements. Using linkage to the western Washington SEER cancer registry, we documented 830 new cases of prostate cancer from baseline through December 2004. A 10-year average intake of supplemental vitamin E was not associated with a reduced prostate cancer risk overall [hazard ratio (HR) 0.86, 95% confidence interval (CI) 0.65-1.1 for > or =400 IU/day vs. non-use, p for trend 0.36]; however, risk for advanced prostate cancer (regionally invasive or distant metastatic, n = 123) decreased significantly with greater intake of supplemental vitamin E (HR 0.43, 95% CI 0.19-1.0 for 10-year average intake > or =400 IU/day vs. non-use, p for trend 0.03). There was no association between selenium supplementation and prostate cancer risk (HR 0.90, 95% CI 0.62-1.3 for 10-year average intake >50 microg/day vs. non-use, p for trend 0.97). In this prospective cohort, long-term supplemental intake of vitamin E and selenium were not associated with prostate cancer risk overall; however, risk of clinically relevant advanced disease was reduced with greater long-term vitamin E supplementation.

  5. Lipid raft involvement in yeast cell growth and death

    Directory of Open Access Journals (Sweden)

    Faustino eMollinedo

    2012-10-01

    Full Text Available The notion that cellular membranes contain distinct microdomains, acting as scaffolds for signal transduction processes, has gained considerable momentum. In particular, a class of such domains that is rich in sphingolipids and cholesterol, termed as lipid rafts, is thought to compartmentalize the plasma membrane, and to have important roles in survival and cell death signaling in mammalian cells. Likewise, yeast lipid rafts are membrane domains enriched in sphingolipids and ergosterol, the yeast counterpart of mammalian cholesterol. Sterol-rich membrane domains have been identified in several fungal species, including the budding yeast Saccharomyces cerevisiae, the fission yeast Schizosaccharomyces pombe as well as the pathogens Candida albicans and Crytococcus neoformans. Yeast rafts have been mainly involved in membrane trafficking, but increasing evidence implicates rafts in a wide range of additional cellular processes. Yeast lipid rafts house biologically important proteins involved in the proper function of yeast, such as proteins that control Na+, K+ and pH homeostasis, which influence many cellular processes, including cell growth and death. Membrane raft constituents affect drug susceptibility, and drugs interacting with sterols alter raft composition and membrane integrity, leading to yeast cell death. Because of the genetic tractability of yeast, analysis of yeast rafts could be an excellent model to approach unanswered questions of mammalian raft biology, and to understand the role of lipid rafts in the regulation of cell death and survival in human cells. A better insight in raft biology might lead to envisage new raft-mediated approaches to the treatment of human diseases where regulation of cell death and survival is critical, such as cancer and neurodegenerative diseases.

  6. Serum selenium level and risk of lung cancer mortality

    DEFF Research Database (Denmark)

    Suadicani, P; Hein, H O; Gyntelberg, F

    2011-01-01

    Serum selenium has been implicated as a risk factor for lung cancer, but the issue remains unsettled. We tested in a cohort of 3,333 males aged 53 to 74 years the hypothesis that a low serum selenium would be associated with an increased risk of lung cancer mortality.During 16 years, 167 subjects(5.......1%) died from lung cancer; 48 males (5.0%) among males with low serum selenium, 0.4-1.0 μmol·l(-1), n=965, 57 males (5.1%) among males with medium serum selenium, 1.1-1.2 μmol·l(-1), n=1,141, and 62 males (5.1%) among males with high serum selenium, 1.3-3.0 μmol·l(-1), n=1,227. After adjustment for age...... (chronic bronchitis and peak flow), referencing the lowest level of serum selenium HRs were 1.17(0.79-1.75), and 1.43(0.96-2.14), respectively. Among heavy smokers a high serum selenium was associated with a significantly increased risk of lung cancer mortality after taking into account all potential...

  7. Selenium impacts on razorback sucker, Colorado: Colorado River: III. Larvae

    Science.gov (United States)

    Hamilton, S.J.; Holley, K.M.; Buhl, K.J.; Bullard, F.A.

    2005-01-01

    Razorback sucker (Xyrauchen texanus) larvae from adults exposed to selenium at three sites near Grand Junction, Colorado, for 9 months were used in a 30-day waterborne and dietary selenium study. Selenium concentrations in water averaged brine shrimp, 5.6 ??g/g in zooplankton from Horsethief east wetland, 20 ??g/g in zooplankton from Adobe Creek, and 39 ??g/g in zooplankton from North Pond. The lowest survival occurred in larvae fed zooplankton rather than brine shrimp. Survival of larvae at Adobe Creek and North Pond was lower in site water than in reference water. Survival of brood stock larvae was higher than Horsethief larvae even though they received the same water and dietary treatments. Arsenic concentrations in brine shrimp may have resulted in an antagonistic interaction with selenium and reduced adverse effects in larvae. Deformities in larvae from North Pond were similar to those reported for selenium-induced teratogenic deformities in other fish species. Selenium concentrations of ???4.6 ??g/g in food resulted in rapid mortality of larvae from Horsethief, Adobe Creek, and North Pond, and suggested that selenium toxicity in the Colorado River could limit recovery of this endangered fish.

  8. Serum Selenium and Ceruloplasmin in Nigerians with Peripartum Cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Kamilu M. Karaye

    2015-04-01

    Full Text Available The study aimed to determine if selenium deficiency, serum ceruloplasmin and traditional birth practices are risk factors for peripartum cardiomyopathy (PPCM, in Kano, Nigeria. This is a case-control study carried out in three hospitals, and PPCM patients were followed up for six months. Critically low serum selenium concentration was defined as <70 µg/L. A total of 39 PPCM patients and 50 controls were consecutively recruited after satisfying the inclusion criteria. Mean serum selenium in patients (61.7 ± 14.9 µg/L was significantly lower than in controls (118.4 ± 45.6 µg/L (p < 0.001. The prevalence of serum selenium <70 µg/L was significantly higher among patients (76.9% than controls (22.0% (p < 0.001. The mean ceruloplasmin and prevalence of socio-economic indices, multiparity, pregnancy-induced hypertension, obesity and twin pregnancy were not different between the groups (p > 0.05. Logistic regression showed that rural residency significantly increased the odds for serum selenium <70 µg/L by 2.773-fold (p = 0.037. Baseline serum levels of selenium and ceruloplasmin were not associated with six-month mortality. This study has shown that selenium deficiency is a risk factor for PPCM in Kano, Nigeria, and is related to rural residency. However, serum ceruloplasmin, customary birth practices and some other characteristics were not associated with PPCM in the study area.

  9. The role of selenium in human conception and pregnancy.

    Science.gov (United States)

    Pieczyńska, Joanna; Grajeta, Halina

    2015-01-01

    Selenium (Se) is a trace element essential for the appropriate course of vital processes in the human body. It is also a constituent of the active center of glutathione peroxidase that protects cellular membranes against the adverse effects of H2O2 lipid peroxides. Epidemiological surveys have demonstrated that selenium deficiency in the body may contribute to an increased risk for certain neoplasmic diseases (including colonic carcinoma, gastric carcinoma, pulmonary carcinoma and prostate carcinoma), as well as diseases of the cardiovascular, osseous and nervous systems. Apart from its cancer prevention and antioxidative activities, selenium protects the body against detrimental effects of heavy metals and determines the proper functioning of the immunological system. Furthermore, selenium plays a significant role in the undisturbed functioning of the reproductive system. Many studies have addressed correlations between its intake and fertility as well as disorders of procreation processes. Selenium deficiencies may lead to gestational complications, miscarriages and the damaging of the nervous and immune systems of the fetus. A low concentration of selenium in blood serum in the early stage of pregnancy has been proved to be a predictor of low birth weight of a newborn. A deficiency of this element may also cause infertility in men by causing a deterioration in the quality of semen and in sperm motility. For this reason, supplementation in the case of selenium deficiencies in the procreation period of both women and men is of utmost significance. Copyright © 2014 Elsevier GmbH. All rights reserved.

  10. Iodine and Selenium Intakes of Postmenopausal Women in New Zealand.

    Science.gov (United States)

    Brough, Louise; Gunn, Caroline A; Weber, Janet L; Coad, Jane; Jin, Ying; Thomson, Jasmine S; Mauze, Mathilde; Kruger, Marlena C

    2017-03-09

    Iodine and selenium are required for thyroid function. This study investigated iodine and selenium intakes in healthy, women aged 50-70 years (n = 97) from three cities in the North Island of New Zealand, after mandatory fortification of bread with iodised salt. Iodine and selenium concentrations were determined in 24-h urine samples; daily intakes were extrapolated from amounts in urine (90% and 55% of daily intake, respectively). Three day diet diaries (3DDD) also estimated selenium and iodine (excluding iodised salt) intake. Median urinary iodine concentration (UIC) was 57 (41, 78) µg/L, indicating mild iodine deficiency. Estimated median iodine intake based on urine was 138 (100, 172) µg/day, below Recommended Dietary Intake (RDI) (150 µg/day) with 25% below Estimated Average Requirement (EAR) (100 µg/day). Estimated median selenium intake was 50 (36, 71) µg/day based on urine and 45 (36, 68) µg/day using 3DDD, below RDI (60 µg/day) with 49%-55% below EAR (50 µg/day). Median bread intakes were low at 1.8 (1.1, 2.7) serves/day; 25% consumed ≤1 serve/day. Although population iodine intakes improved following mandatory fortification, some had low intakes. Selenium intakes remain low. Further research should investigate thyroid function of low consumers of iodine fortified bread and/or selenium in New Zealand.

  11. Genome-Wide Association Study of Serum Selenium Concentrations

    Directory of Open Access Journals (Sweden)

    Ulrike Peters

    2013-05-01

    Full Text Available Selenium is an essential trace element and circulating selenium concentrations have been associated with a wide range of diseases. Candidate gene studies suggest that circulating selenium concentrations may be impacted by genetic variation; however, no study has comprehensively investigated this hypothesis. Therefore, we conducted a two-stage genome-wide association study to identify genetic variants associated with serum selenium concentrations in 1203 European descents from two cohorts: the Prostate, Lung, Colorectal, and Ovarian (PLCO Cancer Screening and the Women’s Health Initiative (WHI. We tested association between 2,474,333 single nucleotide polymorphisms (SNPs and serum selenium concentrations using linear regression models. In the first stage (PLCO 41 SNPs clustered in 15 regions had p < 1 × 10−5. None of these 41 SNPs reached the significant threshold (p = 0.05/15 regions = 0.003 in the second stage (WHI. Three SNPs had p < 0.05 in the second stage (rs1395479 and rs1506807 in 4q34.3/AGA-NEIL3; and rs891684 in 17q24.3/SLC39A11 and had p between 2.62 × 10−7 and 4.04 × 10−7 in the combined analysis (PLCO + WHI. Additional studies are needed to replicate these findings. Identification of genetic variation that impacts selenium concentrations may contribute to a better understanding of which genes regulate circulating selenium concentrations.

  12. Selenium Effect on Oxidative Stress Factors in Septic Rats

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    Elmira Zolali

    2014-05-01

    Full Text Available Purpose: Severe oxidative stress is an important event that occurs in patients with sepsis. The body has extensive and multiple defense mechanisms against the reactive oxygen species (ROS produced during inflammation and sepsis. One of these mechanisms includes a group of enzymes that utilize selenium as their cofactor. The purpose of this study is investigating of Selenium effect on oxidative stress factors in animal model of sepsis. Methods: Sepsis was induced by caecal ligation and puncture (CLP method. 30 Male Wistar rats were divided into following groups: sham group; CLP group; 100 μg/kg Selenium- treated CLP group. 12 hours after inducing sepsis animals were killed and lungs were removed. One of the lungs was frozen in liquid nitrogen and kept at -70°C for enzymatic activity analysis and the other was kept in formalin 10% until tissue section preparation performed for histopathological studies. Results: The Myeloperoxidase (MPO activity was decreased in Selenium- treated CLP group. Inflammation score of lung tissue was lowered in Selenium- treated CLP group, but it wasn’t statically significant. Level of glutathione peroxidase (GPx was higher in CLP and Selenium- treated CLP groups. Conclusion: It seems that Selenium has protective effect on lung inflammation during acute lung injury. Also it may improve some stress oxidative profile during CLP model of sepsis.

  13. Selenium compound protects corneal epithelium against oxidative stress.

    Directory of Open Access Journals (Sweden)

    Akihiro Higuchi

    Full Text Available The ocular surface is strongly affected by oxidative stress, and anti-oxidative systems are maintained in corneal epithelial cells and tear fluid. Dry eye is recognized as an oxidative stress-induced disease. Selenium compound eye drops are expected to be a candidate for the treatment of dry eye. We estimated the efficacy of several selenium compounds in the treatment of dry eye using a dry eye rat model. All of the studied selenium compounds were uptaken into corneal epithelial cells in vitro. However, when the selenium compounds were administered as eye drops in the dry eye rat model, most of the selenium compounds did not show effectiveness except for Se-lactoferrin. Se-lactoferrin is a lactoferrin that we prepared that binds selenium instead of iron. Se-lactoferrin eye drops suppressed the up-regulated expression of heme oxygenase-1, cyclooxygenase-2, matrix metallopeptidase-9, and interleukin-6 and also suppressed 8-OHdG production in the cornea induced by surgical removal of the lacrimal glands. Compared with Se-lactoferrin, apolactoferrin eye drops weakly improved dry eye in high dose. The effect of Se-lactoferrin eye drops on dry eye is possibly due to the effect of selenium and also the effect of apolactoferrin. Se-lactoferrin is a candidate for the treatment of dry eye via regulation of oxidative stress in the corneal epithelium.

  14. Role of calcium in selenium cataract.

    Science.gov (United States)

    Shearer, T R; David, L L

    The purpose of this research was to test the role of certain minerals in the formation of cataract caused by an overdose of selenium. Several pieces of information indicated that lenticular calcium may play an important role in selenite cataractogenesis: 1) Lens calcium concentrations in selenite treated rats were increased more than 5-fold, and the increase in lens calcium was localized in the nucleus. 2) Lens calcium concentrations were elevated at least one full day before actual formation of nuclear cataract, but serum calcium levels were not changed. 3) In older rats not susceptible to selenite cataract, lens calcium was not significantly increased. 4) No evidence was found for a generalized disruption in lens permeability, since no major changes in lens water, sodium, and potassium levels were observed, and 5) when levels of calcium observed in selenite cataract were added to solutions of soluble proteins from rat lenses, light scattering was increased. Selenium-overdose cataracts may provide an important model for studies on the role of calcium in cataractogenesis.

  15. Biofortification and phytoremediation of selenium in China

    Directory of Open Access Journals (Sweden)

    Zhilin eWu

    2015-03-01

    Full Text Available Selenium (Se is an essential trace element for humans and animals but at high concentrations, Se becomes toxic to organisms due to Se replacing sulfur in proteins. Selenium biofortification is an agricultural process that increases the accumulation of Se in crops, through plant breeding, genetic engineering, or use of Se fertilizers. While Se phytoremediation is a green biotechnology to clean up Se-contaminated environments, primarily through phytoextraction and phytovolatilization. By integrating Se phytoremediation and biofortification technologies, Se-enriched plant materials harvested from Se phytoremediation can be used as Se-enriched green manures or other supplementary sources of Se for producing Se-biofortified agricultural products. Earlier studies primarily aimed at enhancing efficacy of phytoremediation and biofortification of Se based on natural variation in progenitor or identification of unique plant species. In this review, we discuss promising approaches to improve biofortification and phytoremediation of Se using knowledge acquired from model crops. We also explored the feasibility of applying biotechnologies such as inoculation of microbial strains for improving the efficiency of biofortification and phytoremediation of Se. The key research and practical challenges that remain in improving biofortification and phytoremediation of Se have been highlighted, and the future development and uses of Se-biofortified agricultural products in China has also been discussed.

  16. Bacterial respiration of arsenic and selenium

    Science.gov (United States)

    Stolz, J.F.; Oremland, R.S.

    1999-01-01

    Oxyanions of arsenic and selenium can be used in microbial anaerobic respiration as terminal electron acceptors. The detection of arsenate and selenate respiring bacteria in numerous pristine and contaminated environments and their rapid appearance in enrichment culture suggest that they are widespread and metabolically active in nature. Although the bacterial species that have been isolated and characterized are still few in number, they are scattered throughout the bacterial domain and include Gram- positive bacteria, beta, gamma and epsilon Proteobacteria and the sole member of a deeply branching lineage of the bacteria, Chrysiogenes arsenatus. The oxidation of a number of organic substrates (i.e. acetate, lactate, pyruvate, glycerol, ethanol) or hydrogen can be coupled to the reduction of arsenate and selenate, but the actual donor used varies from species to species. Both periplasmic and membrane-associated arsenate and selenate reductases have been characterized. Although the number of subunits and molecular masses differs, they all contain molybdenum. The extent of the environmental impact on the transformation and mobilization of arsenic and selenium by microbial dissimilatory processes is only now being fully appreciated.

  17. Selenium for the prevention of cutaneous melanoma.

    Science.gov (United States)

    Cassidy, Pamela B; Fain, Heidi D; Cassidy, James P; Tran, Sally M; Moos, Philip J; Boucher, Kenneth M; Gerads, Russell; Florell, Scott R; Grossman, Douglas; Leachman, Sancy A

    2013-03-07

    The role of selenium (Se) supplementation in cancer prevention is controversial; effects often depend on the nutritional status of the subject and on the chemical form in which Se is provided. We used a combination of in vitro and in vivo models to study two unique therapeutic windows for intervention in the process of cutaneous melanomagenisis, and to examine the utility of two different chemical forms of Se for prevention and treatment of melanoma. We studied the effects of Se in vitro on UV-induced oxidative stress in melanocytes, and on apoptosis and cell cycle progression in melanoma cells. In vivo, we used the HGF transgenic mouse model of UV-induced melanoma to demonstrate that topical treatment with l-selenomethionine results in a significant delay in the time required for UV-induced melanoma development, but also increases the rate of growth of those tumors once they appear. In a second mouse model, we found that oral administration of high dose methylseleninic acid significantly decreases the size of human melanoma xenografts. Our findings suggest that modestly elevation of selenium levels in the skin might risk acceleration of growth of incipient tumors. Additionally, certain Se compounds administered at very high doses could have utility for the treatment of fully-malignant tumors or prevention of recurrence.

  18. Selenium for the Prevention of Cutaneous Melanoma

    Directory of Open Access Journals (Sweden)

    Douglas Grossman

    2013-03-01

    Full Text Available The role of selenium (Se supplementation in cancer prevention is controversial; effects often depend on the nutritional status of the subject and on the chemical form in which Se is provided. We used a combination of in vitro and in vivo models to study two unique therapeutic windows for intervention in the process of cutaneous melanomagenisis, and to examine the utility of two different chemical forms of Se for prevention and treatment of melanoma. We studied the effects of Se in vitro on UV-induced oxidative stress in melanocytes, and on apoptosis and cell cycle progression in melanoma cells. In vivo, we used the HGF transgenic mouse model of UV-induced melanoma to demonstrate that topical treatment with l-selenomethionine results in a significant delay in the time required for UV-induced melanoma development, but also increases the rate of growth of those tumors once they appear. In a second mouse model, we found that oral administration of high dose methylseleninic acid significantly decreases the size of human melanoma xenografts. Our findings suggest that modestly elevation of selenium levels in the skin might risk acceleration of growth of incipient tumors. Additionally, certain Se compounds administered at very high doses could have utility for the treatment of fully-malignant tumors or prevention of recurrence.

  19. Defining the Optimal Selenium Dose for Prostate Cancer Risk Reduction: Insights from the U-Shaped Relationship between Selenium Status, DNA Damage, and Apoptosis

    OpenAIRE

    Emily C. Chiang; Shen, Shuren; Kengeri, Seema S.; Xu, Huiping; Combs, Gerald F.; Morris, J. Steven; Bostwick, David G.; Waters, David J.

    2009-01-01

    Our work in dogs has revealed a U-shaped dose response between selenium status and prostatic DNA damage that remarkably parallels the relationship between dietary selenium and prostate cancer risk in men, suggesting that more selenium is not necessarily better. Herein, we extend this canine work to show that the selenium dose that minimizes prostatic DNA damage also maximizes apoptosis—a cancer-suppressing death switch used by prostatic epithelial cells. These provocative findings suggest a n...

  20. An Introduction to Testing Web Applications with twill and Selenium

    CERN Document Server

    Brown, Titus; Huggins, Jason

    2007-01-01

    This Short Cut is an introduction tobuilding automated web tests using twotools, twill and Selenium. twill is a simpleweb scripting language that can be usedto automate web tests, while Selenium isa web testing framework that runs in anybrowser and can be used to test complexweb sites that make extensive use ofJavaScript. The best way to use this Short Cut is torun through the examples. We expectthat within an hour you can start writingyour own functional tests in either twillor Selenium, and within a day you willunderstand most, if not all, of the possibilitiesand the limitations of these t

  1. Total selenium and selenium species in irrigation drain inflows to the Salton Sea, California, April and July 2007

    Science.gov (United States)

    May, Thomas W.; Walther, Michael J.; Saiki, Michael K.; Brumbaugh, William G.

    2007-01-01

    This report presents the results for two sampling periods during a 4-year monitoring survey to provide a characterization of selenium concentrations in selected irrigation drains flowing into the Salton Sea, California. Total selenium, selenium species, and total suspended solids were determined in water samples, and total selenium was determined in sediment, detritus, and biota that included algae, plankton, midge larvae (family, Chironomidae), and two fish species-western mosquitofish (Gambusia affinis), and sailfin molly (Poecilia latipinna). In addition, sediments were analyzed for percent total organic carbon and particle size. Total selenium concentrations in water for both sampling periods ranged from 1.43 to 47.1 micrograms per liter, predominately as selenate, which is typical of waters leached out of selenium-contaminated marine shales under alkaline and oxidizing conditions. Total selenium concentrations ranged from 0.88 to 20.2 micrograms per gram in biota, and from 0.15 to 28.9 micrograms per gram in detritus and sediment.

  2. Biochemical discrimination between selenium and sulfur 1: a single residue provides selenium specificity to human selenocysteine lyase.

    Directory of Open Access Journals (Sweden)

    Ruairi Collins

    Full Text Available Selenium and sulfur are two closely related basic elements utilized in nature for a vast array of biochemical reactions. While toxic at higher concentrations, selenium is an essential trace element incorporated into selenoproteins as selenocysteine (Sec, the selenium analogue of cysteine (Cys. Sec lyases (SCLs and Cys desulfurases (CDs catalyze the removal of selenium or sulfur from Sec or Cys and generally act on both substrates. In contrast, human SCL (hSCL is specific for Sec although the only difference between Sec and Cys is the identity of a single atom. The chemical basis of this selenium-over-sulfur discrimination is not understood. Here we describe the X-ray crystal structure of hSCL and identify Asp146 as the key residue that provides the Sec specificity. A D146K variant resulted in loss of Sec specificity and appearance of CD activity. A dynamic active site segment also provides the structural prerequisites for direct product delivery of selenide produced by Sec cleavage, thus avoiding release of reactive selenide species into the cell. We thus here define a molecular determinant for enzymatic specificity discrimination between a single selenium versus sulfur atom, elements with very similar chemical properties. Our findings thus provide molecular insights into a key level of control in human selenium and selenoprotein turnover and metabolism.

  3. Age-related Cataract in a Randomized Trial of Selenium and Vitamin E in Men: The SELECT Eye Endpoints (SEE) Study

    Science.gov (United States)

    Christen, William G.; Glynn, Robert J.; Gaziano, J. Michael; Darke, Amy K.; Crowley, John J.; Goodman, Phyllis J.; Lippman, Scott M.; Lad, Thomas E.; Bearden, James D.; Goodman, Gary E.; Minasian, Lori M.; Thompson, Ian M.; Blanke, Charles D.; Klein, Eric A.

    2014-01-01

    Importance Observational studies suggest a role for dietary nutrients such as vitamin E and selenium in cataract prevention. However, the results of randomized trials of vitamin E supplements and cataract have been disappointing, and are not yet available for selenium. Objective To test whether long-term supplementation with selenium and vitamin E affects the incidence of cataract in a large cohort of men. Design, Setting, and Participants The SELECT Eye Endpoints (SEE) study was an ancillary study of the SWOG-coordinated Selenium and Vitamin E Cancer Prevention Trial (SELECT), a randomized, placebo-controlled, four arm trial of selenium and vitamin E conducted among 35,533 men aged 50 years and older for African Americans and 55 and older for all other men, at 427 participating sites in the US, Canada, and Puerto Rico. A total of 11,267 SELECT participants from 128 SELECT sites participated in the SEE ancillary study. Intervention Individual supplements of selenium (200 µg/d from L-selenomethionine) and vitamin E (400 IU/d of all rac-α-tocopheryl acetate). Main Outcome Measures Incident cataract, defined as a lens opacity, age-related in origin, responsible for a reduction in best-corrected visual acuity to 20/30 or worse based on self-report confirmed by medical record review, and cataract extraction, defined as the surgical removal of an incident cataract. Results During a mean (SD) of 5.6 (1.2) years of treatment and follow-up, 389 cases of cataract were documented. There were 185 cataracts in the selenium group and 204 in the no selenium group (hazard ratio [HR], 0.91; 95 percent confidence interval [CI], 0.75 to 1.11; P=.37). For vitamin E, there were 197 cases in the treated group and 192 in the placebo group (HR, 1.02; CI, 0.84 to 1.25; P=.81). Similar results were observed for cataract extraction. Conclusions and Relevance These randomized trial data from a large cohort of apparently healthy men indicate that long-term daily supplementation with selenium

  4. Age-related cataract in men in the selenium and vitamin e cancer prevention trial eye endpoints study: a randomized clinical trial.

    Science.gov (United States)

    Christen, William G; Glynn, Robert J; Gaziano, J Michael; Darke, Amy K; Crowley, John J; Goodman, Phyllis J; Lippman, Scott M; Lad, Thomas E; Bearden, James D; Goodman, Gary E; Minasian, Lori M; Thompson, Ian M; Blanke, Charles D; Klein, Eric A

    2015-01-01

    Observational studies suggest a role for dietary nutrients such as vitamin E and selenium in cataract prevention. However, the results of randomized clinical trials of vitamin E supplements and cataract have been disappointing and are not yet available for selenium. To test whether long-term supplementation with selenium and vitamin E affects the incidence of cataract in a large cohort of men. The Selenium and Vitamin E Cancer Prevention Trial (SELECT) Eye Endpoints Study was an ancillary study of the Southwest Oncology Group-coordinated SELECT, a randomized placebo-controlled 4-arm trial of selenium and vitamin E conducted among 35,533 men, 50 years and older for African American participants and 55 years and older for all other men, at 427 participating sites in the United States, Canada, and Puerto Rico. A total of 11,267 SELECT participants from 128 SELECT sites participated in the SELECT Eye Endpoints ancillary study. Individual supplements of selenium (200 μg per day from L-selenomethionine) and vitamin E (400 IU per day of all rac-α-tocopheryl acetate). Incident cataract was defined as a lens opacity, age related in origin, and responsible for a reduction in best-corrected visual acuity to 20/30 or worse based on self-reports confirmed by medical record review. Cataract extraction was defined as the surgical removal of an incident cataract. During a mean (SD) of 5.6 (1.2) years of treatment and follow-up, 389 cases of cataract were documented. There were 185 cataracts in the selenium group and 204 in the no selenium group (hazard ratio, 0.91; 95 % CI, 0.75-1.11; P = .37). For vitamin E, there were 197 cases in the treated group and 192 in the placebo group (hazard ratio, 1.02; 95 % CI, 0.84-1.25; P = .81). Similar results were observed for cataract extraction. These data from a large cohort of apparently healthy men indicate that long-term daily supplementation with selenium and/or vitamin E is unlikely to have a large beneficial effect on age

  5. Effects of Dietary Selenium, Sulphur and Copper Levels on Selenium Concentration in the Serum and Liver of Lamb

    Directory of Open Access Journals (Sweden)

    Arlindo Saran Netto

    2014-08-01

    Full Text Available Thirty-two lambs were distributed in eight treatments under 2×2×2 factorial experiment to compare the effects of two levels of selenium (0.2 to 5 mg/kg dry matter [DM], sulphur (0.25% and 0.37% and copper (8 and 25 mg/kg DM levels on selenium concentration in liver and serum of lambs. A liver biopsy was done on all animals and blood samples were collected from the jugular vein prior to the beginning of the treatments. The blood was sampled every thirty days and the liver was sampled after 90 days, at the slaughter. Increasing differences were noticed during the data collection period for the serum selenium concentration, and it was found to be 0.667 mg/L in animals fed with 5 mg Se/kg DM and normal sulphur and copper concentrations in their diet. However, a three-way interaction and a reduction of selenium concentration to 0.483 mg/L was verified when increasing copper and sulphur concentration levels to 25 ppm and 0.37% respectively. The liver selenium concentration was also high for diets containing higher selenium concentrations, but the antagonist effect with the increased copper and sulphur levels remained, due to interactions between these minerals. Therefore, for regions where selenium is scarce, increasing its concentration in animal diets can be an interesting option. For regions with higher levels of selenium, the antagonistic effect of interaction between these three minerals should be used by increasing copper and sulphur dietary concentrations, thus preventing possible selenium poisoning.

  6. Extracellular Polysaccharides Produced by Yeasts and Yeast-Like Fungi

    Science.gov (United States)

    van Bogaert, Inge N. A.; de Maeseneire, Sofie L.; Vandamme, Erick J.

    Several yeasts and yeast-like fungi are known to produce extracellular polysaccharides. Most of these contain D-mannose, either alone or in combination with other sugars or phosphate. A large chemical and structural variability is found between yeast species and even among different strains. The types of polymers that are synthesized can be chemically characterized as mannans, glucans, phosphoman-nans, galactomannans, glucomannans and glucuronoxylomannans. Despite these differences, almost all of the yeast exopolysaccharides display some sort of biological activity. Some of them have already applications in chemistry, pharmacy, cosmetics or as probiotic. Furthermore, some yeast exopolysaccharides, such as pullulan, exhibit specific physico-chemical and rheological properties, making them useful in a wide range of technical applications. A survey is given here of the production, the characteristics and the application potential of currently well studied yeast extracellular polysaccharides.

  7. Influence of different amounts and sources of selenium supplementation on performance, some blood parameters, and nutrient digestibility in lambs.

    Science.gov (United States)

    Alimohamady, Reza; Aliarabi, Hassan; Bahari, Aliasghar; Dezfoulian, Amir Hossein

    2013-07-01

    Two trials were conducted in a 2 × 2 + 1 factorial arrangement based on a completely randomized design to evaluate the effects of different sources of selenium (Se) on performance, blood metabolites, and nutrient digestibility in male lambs on a barley-based diet. The first trial lasted for 70 days and consisted of 30 lambs (35.6 ± 2.6 kg mean body weight, about 4-5 months of age) which were randomly allotted to five treatments including: (1) basal diet (containing 0.06 mg Se/kg DM; control) without supplementary Se, (2) basal diet + 0.20 mg/kg Se as sodium selenite (SeS 0.20), (3) basal diet + 0.40 mg/kg Se as sodium selenite (SeS 0.40), (4) basal diet + 0.20 mg/kg Se as selenium yeast (SeY 0.20), and (5) basal diet + 0.40 mg/kg Se as selenium yeast (SeY 0.40). For the second trial, four lambs from each group of experiment 1 were randomly allocated to individual metabolic cages for 14 days to measure the effects of dietary Se on nutrient digestibility. The results revealed that there were no significant differences for average daily gain, average daily feed intake, feed/gain ratio, hematological parameters (packed cell volume, red blood cell, white blood cell, and hemoglobin values), serum total protein, albumin, globulin, aspartate amino transferase, alkaline phosphatase, and creatine phosphokinase due to supplementation of different amounts and sources of Se in lambs. Dietary Se supplementation significantly improved (P supplementation. It may be concluded that supplementation of Se in lambs had no significant effect on performance and blood hematology, but increased blood glutathione peroxidase activity and serum T3 amount and decreased serum T4 amount as compared to non-supplemented control lambs. Furthermore, Se yeast improved nutrient digestibility in lambs.

  8. Yeast cells proliferation on various strong static magnetic fields and temperatures

    Science.gov (United States)

    Otabe, E. S.; Kuroki, S.; Nikawa, J.; Matsumoto, Y.; Ooba, T.; Kiso, K.; Hayashi, H.

    2009-03-01

    The effect of strong magnetic fields on activities of yeast cells were investigated. Experimental yeast cells were cultured in 5 ml of YPD(Yeast extract Peptone Dextrose) for the number density of yeast cells of 5.0 ±0.2 x 106/ml with various temperatures and magnetic fields up to 10 T. Since the yeast cells were placed in the center of the superconducting magnet, the effect of magnetic force due to the diamagnetism and magnetic gradient was negligibly small. The yeast suspension was opened to air and cultured in shaking condition. The number of yeast cells in the yeast suspension was counted by a counting plate with an optical microscope, and the time dependence of the number density of yeast cells was measured. The time dependence of the number density of yeast cells, ρ, of initial part is analyzed in terms of Malthus equation as given by ρ = ρo exp(kt), where k is the growth coefficient. It is found that, the growth coefficient under the magnetic field is suppressed compared with the control. The growth coefficient decreasing as increasing magnetic field and is saturated at about 5 T. On the other hand, it is found that the suppression of growth of yeast cells by the magnetic field is diminished at high temperatures.

  9. Yeast cells proliferation on various strong static magnetic fields and temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Otabe, E S; Kuroki, S; Nikawa, J [Faculty of Computer Science and Systems Engineering, Kyushu Institute of Technology, 680-4 Kawazu Iizuka Fukuoka 820-8502 (Japan); Matsumoto, Y [Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka 814-0180 (Japan); Ooba, T [Fukuoka Industrial Technology Center, 1465-5 Aikawa-machi, Kurume, Fukuoka 839-0861 (Japan); Kiso, K [Fukuoka Regional Taxation Bureau, 2-11-1 Hakataekihigashi, Hakata-ku Fukuoka, 812-8547 (Japan); Hayashi, H [Kyushu Power Electric, 2-1-47 Shiobaru Minami-ku Fukuoka 815-8520 (Japan)], E-mail: otabe@cse.kyutech.ac.jp

    2009-03-01

    The effect of strong magnetic fields on activities of yeast cells were investigated. Experimental yeast cells were cultured in 5 ml of YPD(Yeast extract Peptone Dextrose) for the number density of yeast cells of 5.0 {+-}0.2 x 10{sup 6}/ml with various temperatures and magnetic fields up to 10 T. Since the yeast cells were placed in the center of the superconducting magnet, the effect of magnetic force due to the diamagnetism and magnetic gradient was negligibly small. The yeast suspension was opened to air and cultured in shaking condition. The number of yeast cells in the yeast suspension was counted by a counting plate with an optical microscope, and the time dependence of the number density of yeast cells was measured. The time dependence of the number density of yeast cells, {rho}, of initial part is analyzed in terms of Malthus equation as given by {rho} = {rho}o exp(kt), where k is the growth coefficient. It is found that, the growth coefficient under the magnetic field is suppressed compared with the control. The growth coefficient decreasing as increasing magnetic field and is saturated at about 5 T. On the other hand, it is found that the suppression of growth of yeast cells by the magnetic field is diminished at high temperatures.

  10. Selenium in aquatic habitats at Imperial National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — During 1991 and 1992, selenium levels were studied in aquatic communities at Imperial National Wildlife Refuge on the lower Colorado River. Composite samples of...

  11. Early development of selenium-induced cataract: slit lamp evaluation.

    Science.gov (United States)

    Shearer, T R; Anderson, R S; Britton, J L; Palmer, E A

    1983-06-01

    The purpose of our research was to document early lenticular changes preceding cataract formation in rats receiving an elevated dose of selenium. The following stages were observed after selenium injection: Stage 1 (13-24 hr post-injection), formation of posterior equatorial subcapsular cataract (PESC); Stage 2 (24-72 hr), decline of the PESC, development of a prominent 'washer' shaped change in the refraction of the cortex, and first appearance of swollen fibers around the nucleus; Stage 3 (three to five days), appearance of bilateral dense central nuclear cataracts and further development of perinuclear swollen fibers; Stage 4 (five to 10 days), some nuclear cataracts became more opaque and/or angular. The results are consistent with the hypothesis that the initial site of action of selenium in nuclear cataract formation is not in the lens nucleus. Rather, selenium causes early changes outside the nucleus, which are followed by nuclear cataracts.

  12. BACTERIAL RESPIRATION OF ARSENIC AND SELENIUM. (R826105)

    Science.gov (United States)

    AbstractOxyanions of arsenic and selenium can be used in microbial anaerobic respiration as terminal electron acceptors. The detection of arsenate and selenate respiring bacteria in numerous pristine and contaminated environments and their rapid appearance in enrichme...

  13. Arsenic, chromium, copper, iron, manganese, lead, selenium and ...

    African Journals Online (AJOL)

    Arsenic, chromium, copper, iron, manganese, lead, selenium and zinc in the tissues of the largemouth yellowfish, Labeobarbus kimberleyensis (Gilchrist and Thompson, 1913), from the Vaal Dam, South Africa, and associated consumption risks.

  14. Concentrations of plasma copper and zinc and blood selenium in ...

    African Journals Online (AJOL)

    Department of Human and Animal Physiology, University of Stellenbosch, Stellenbosch 7600, ... Concentrations of plasma copper and zinc as well as blood selenium were determined in ..... metabolism: Current aspects in health and disease.

  15. Union Slough National Wildlife Refuge, Iowa: Avian selenium study

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In 2006 and 2007, we tested selenium concentrations in the eggs and nestling carcasses of tree swallows attracted to artificial nest boxes installed around Union...

  16. Mixed Surfactant Template Method for Preparation of Nanometer Selenium

    Directory of Open Access Journals (Sweden)

    Zhi-Lin Li

    2009-01-01

    Full Text Available Selenium nanoparticles have been synthesized in an aqueous solution by using sodium dodecyl sulfate and polyvinyl alcohol as a soft template. The factors on synthesis, such as reaction time, concentration of reactants and ultrasonic irradiation were studied. The uniform stable selenium nanospheres were obstained in the conditions of 1.0 (mass fraction sodium dodecyl sulfate, 1.0 (mass fraction polyvinyl alcohol, n(Vc:n(H2SeO3=7:1 and 7 minutes after the initiation of the reaction at room temperature. The average particle size of selenium is about 30 nm. The product was characterized by UV and TEM. Finally the applications of the red element nanometer selenium in anti-older cosmetics are presented.

  17. Yeasts in Hevea brasiliensis Latex.

    Science.gov (United States)

    Glushakova, A M; Kachalkin, A V; Maksimova, I A; Chernov, I Yu

    2016-07-01

    Yeast abundance and species diversity in the latex of caoutchouc tree Hevea brasiliensis (Willd. ex Juss.) M611. Arg., on its green leaves, and in soil below the plant Was studied. The yeasts present in the fresh latex in concentrations of up to 5.5 log(CFU/g) were almost exclusively represented by the species Candida heveicola, which was previously isolated from Hevea latex in China. In the course of natural modification of the latex yeast diversity increased, while yeast abundance decreased. The yeasts of thickened and solidified latex were represented by typical epiphytic and ubiquitous species: Kodamea ohmeri, Debaryomyces hansenii, Rhodotorula mucilaginosa, and synanthropic species Candida parapsilosis and Cutaneotrichosporon arbori- formis. The role of yeasts in latex modification at the initial stages of succession and their probable role in de- velopment of antifungal activity in the latex are discussed.

  18. Investigation of evaporation characteristics of polonium and its lighter homologues selenium and tellurium from liquid Pb-Bi-eutecticum

    CERN Document Server

    Neuhausen, J; Eichler, B

    2004-01-01

    The evaporation behaviour of polonium and its lighter homologues selenium and tellurium dissolved in liquid Pb-Bi-eutecticum (LBE) has been studied at various temperatures in the range from 482 K up to 1330 K under Ar/H2 and Ar/H2O-atmospheres using γ-ray spectroscopy. Polonium release in the temperature range of interest for technical applications is slow. Within short term (1h) experiments measurable amounts of polonium are evaporated only at temperatures above 973 K. Long term experiments reveal that a slow evaporation of polonium occurs at temperatures around 873 K resulting in a fractional polonium loss of the melt around 1% per day. Evaporation rates of selenium and tellurium are smaller than those of polonium. The presence of H2O does not enhance the evaporation within the error limits of our experiments. The thermodynamics and possible reaction pathways involved in polonium release from LBE are discussed.

  19. Mercury and selenium levels, and selenium:mercury molar ratios of brain, muscle and other tissues in bluefish (Pomatomus saltatrix) from New Jersey, USA

    Science.gov (United States)

    Burger, Joanna; Jeitner, Christian; Donio, Mark; Pittfield, Taryn; Gochfeld, Michael

    2015-01-01

    A number of contaminants affect fish health, including mercury and selenium, and the selenium: mercury molar ratio. Recently the protective effects of selenium on methylmercury toxicity have been publicized, particularly for consumption of saltwater fish. Yet the relative ameliorating effects of selenium on toxicity within fish have not been examined, nor has the molar ratio in different tissues, (i.e. brain). We examined mercury and selenium levels in brain, kidney, liver, red and white muscle, and skin and scales in bluefish (Pomatomus saltatrix) from New Jersey to determine whether there were toxic levels of either metal, and we computed the selenium: mercury molar ratios by tissues. Total mercury averaged 0.32 ± 0.02 ppm wet weight in edible muscle and 0.09 ± 0.01 ppm in brain. Selenium concentration averaged 0.37 ± 0.03 in muscle and 0.36 ± 0.03 ppm in brain. There were significant differences in levels of mercury, selenium, and selenium: mercury molar ratios, among tissues. Mercury and selenium levels were correlated in kidney and skin/scales. Mercury levels were highest in kidney, intermediate in muscle and liver, and lowest in brain and skin/scales; selenium levels were also highest in kidney, intermediate in liver, and were an order of magnitude lower in the white muscle and brain. Mercury levels in muscle, kidney and skin/scales were positively correlated with fish size (length). Selenium levels in muscle, kidney and liver were positively correlated with fish length, but in brain; selenium levels were negatively correlated with fish length. The selenium: mercury molar ratio was negatively correlated with fish length for white muscle, liver, kidney, and brain, particularly for fish over 50 cm in length, suggesting that older fish experience less protective advantages of selenium against mercury toxicity than smaller fish, and that consumers of bluefish similarly receive less advantage from eating larger fish. PMID:23202378

  20. Selenium and lung cancer: a systematic review and meta analysis.

    Directory of Open Access Journals (Sweden)

    Heidi Fritz

    Full Text Available Selenium is a natural health product widely used in the treatment and prevention of lung cancers, but large chemoprevention trials have yielded conflicting results. We conducted a systematic review of selenium for lung cancers, and assessed potential interactions with conventional therapies.Two independent reviewers searched six databases from inception to March 2009 for evidence pertaining to the safety and efficacy of selenium for lung cancers. Pubmed and EMBASE were searched to October 2009 for evidence on interactions with chemo- or radiation-therapy. In the efficacy analysis there were nine reports of five RCTs and two biomarker-based studies, 29 reports of 26 observational studies, and 41 preclinical studies. Fifteen human studies, one case report, and 36 preclinical studies were included in the interactions analysis. Based on available evidence, there appears to be a different chemopreventive effect dependent on baseline selenium status, such that selenium supplementation may reduce risk of lung cancers in populations with lower baseline selenium status (serum<106 ng/mL, but increase risk of lung cancers in those with higher selenium (≥ 121.6 ng/mL. Pooling data from two trials yielded no impact to odds of lung cancer, OR 0.93 (95% confidence interval 0.61-1.43; other cancers that were the primary endpoints of these trials, OR 1.51 (95%CI 0.70-3.24; and all-cause-death, OR 0.93 (95%CI 0.79-1.10. In the treatment of lung cancers, selenium may reduce cisplatin-induced nephrotoxicity and side effects associated with radiation therapy.Selenium may be effective for lung cancer prevention among individuals with lower selenium status, but at present should not be used as a general strategy for lung cancer prevention. Although promising, more evidence on the ability of selenium to reduce cisplatin and radiation therapy toxicity is required to ensure that therapeutic efficacy is maintained before any broad clinical recommendations can be made in

  1. Yeast interactions and wine flavour.

    Science.gov (United States)

    Fleet, Graham H

    2003-09-01

    Wine is the product of complex interactions between fungi, yeasts and bacteria that commence in the vineyard and continue throughout the fermentation process until packaging. Although grape cultivar and cultivation provide the foundations of wine flavour, microorganisms, especially yeasts, impact on the subtlety and individuality of the flavour response. Consequently, it is important to identify and understand the ecological interactions that occur between the different microbial groups, species and strains. These interactions encompass yeast-yeast, yeast-filamentous fungi and yeast-bacteria responses. The surface of healthy grapes has a predominance of Aureobasidium pullulans, Metschnikowia, Hanseniaspora (Kloeckera), Cryptococcus and Rhodotorula species depending on stage of maturity. This microflora moderates the growth of spoilage and mycotoxigenic fungi on grapes, the species and strains of yeasts that contribute to alcoholic fermentation, and the bacteria that contribute to malolactic fermentation. Damaged grapes have increased populations of lactic and acetic acid bacteria that impact on yeasts during alcoholic fermentation. Alcoholic fermentation is characterised by the successional growth of various yeast species and strains, where yeast-yeast interactions determine the ecology. Through yeast-bacterial interactions, this ecology can determine progression of the malolactic fermentation, and potential growth of spoilage bacteria in the final product. The mechanisms by which one species/strain impacts on another in grape-wine ecosystems include: production of lytic enzymes, ethanol, sulphur dioxide and killer toxin/bacteriocin like peptides; nutrient depletion including removal of oxygen, and production of carbon dioxide; and release of cell autolytic components. Cell-cell communication through quorum sensing molecules needs investigation.

  2. Effect of organic and inorganic selenium supplementation on growth ...

    African Journals Online (AJOL)

    Ninety-six thousand one-day-old AA broilers were randomly assigned to two groups, 5 replicates in each group, and 9,600 chickens for each replicate. In the control group, 0.3 part per million (ppm) inorganic selenium (Na2SeO3) was added to the diets; while in the experimental group, 0.3 ppm organic selenium ...

  3. Effects of selenium biofortification on crop nutritional quality

    OpenAIRE

    Mario eMalagoli; Michela eSchiavon; Stefano eDall'Acqua; Pilon-Smits, Elizabeth A. H.

    2015-01-01

    Selenium (Se) at very low doses has crucial functions in humans and animals. Since plants represent the main dietary source of this element, Se-containing crops may be used as a means to deliver Se to consumers (biofortification). Several strategies have been exploited to increase plant Se content. Selenium assimilation in plants affects both sulfur (S) and nitrogen (N) metabolic pathways, which is why recent research has also focused on the effect of Se fertilization on the production of S- ...

  4. Selenium transformation in coal mine spoils: Its environmental impact assessment

    Energy Technology Data Exchange (ETDEWEB)

    Harness, J.; Atalay, A.; Koll, K.J.; Zhang, H.; Maggon, D.

    1991-12-31

    The objective of this program was to conduct an environmental impact assessment study for selenium from coal mine spoils. The use of in-situ lysimetry to predict selenium speciation, transformation, and mobility under natural conditions was evaluated. The scope of the study was to construct and test field-scale lysimeter and laboratory mini-column to assess mobility and speciation of selenium in coal mine overburden and soil systems; to conduct soil and groundwater sampling throughout the state of Oklahoma for an overall environmental impact assessment of selenium; and to conduct an in-depth literature review on the solubility, speciation, mobility, and toxicity of selenium from various sources. Groundwater and surface soil samples were also collected from each county in Oklahoma. Data collected from the lysimeter study indicated that selenium in the overburden of the abandoned mine site was mainly found in the selenite form. The amount of selenite found was too low and immobile to be of concern to the environment. The spoil had equilibrated long enough (over 50 years) that most of the soluble forms of selenium have already been lost. Examination of the overburden indicated the presence of pyrite crystals that precipitated over time. The laboratory mini-column study indicated that selenite is quite immobile and remained on the overburden material even after leaching with dilute acid. Data from groundwater samples indicated that based on the current permissible level for selenium in groundwater (0.01 mg Se/L), Oklahoma groundwater is widely contaminated with the element. However, according to the new regulation (0.05 mg Se/L), which is to be promulgated in 1992, only 9 of the 77 counties in the state exceed the limit.

  5. Guidelines and recommendations on yeast cell death nomenclature

    Directory of Open Access Journals (Sweden)

    Didac Carmona-Gutierrez

    2018-01-01

    Full Text Available Elucidating the biology of yeast in its full complexity has major implications for science, medicine and industry. One of the most critical processes determining yeast life and physiology is cellular demise. However, the investigation of yeast cell death is a relatively young field, and a widely accepted set of concepts and terms is still missing. Here, we propose unified criteria for the definition of accidental, regulated, and programmed forms of cell death in yeast based on a series of morphological and biochemical criteria. Specifically, we provide consensus guidelines on the differential definition of terms including apoptosis, regulated necrosis, and autophagic cell death, as we refer to additional cell death routines that are relevant for the biology of (at least some species of yeast. As this area of investigation advances rapidly, changes and extensions to this set of recommendations will be implemented in the years to come. Nonetheless, we strongly encourage the authors, reviewers and editors of scientific articles to adopt these collective standards in order to establish an accurate framework for yeast cell death research and, ultimately, to accelerate the progress of this vibrant field of research.

  6. Flavour-active wine yeasts

    OpenAIRE

    Cordente, Antonio G.; Curtin, Christopher D.; Varela, Cristian; Pretorius, Isak S.

    2012-01-01

    The flavour of fermented beverages such as beer, cider, saké and wine owe much to the primary fermentation yeast used in their production, Saccharomyces cerevisiae. Where once the role of yeast in fermented beverage flavour was thought to be limited to a small number of volatile esters and higher alcohols, the discovery that wine yeast release highly potent sulfur compounds from non-volatile precursors found in grapes has driven researchers to look more closely at how choice of yeast can infl...

  7. Oxidative Stress and Programmed Cell Death in Yeast

    Science.gov (United States)

    Farrugia, Gianluca; Balzan, Rena

    2012-01-01

    Yeasts, such as Saccharomyces cerevisiae, have long served as useful models for the study of oxidative stress, an event associated with cell death and severe human pathologies. This review will discuss oxidative stress in yeast, in terms of sources of reactive oxygen species (ROS), their molecular targets, and the metabolic responses elicited by cellular ROS accumulation. Responses of yeast to accumulated ROS include upregulation of antioxidants mediated by complex transcriptional changes, activation of pro-survival pathways such as mitophagy, and programmed cell death (PCD) which, apart from apoptosis, includes pathways such as autophagy and necrosis, a form of cell death long considered accidental and uncoordinated. The role of ROS in yeast aging will also be discussed. PMID:22737670

  8. Nuclear-based methods for the study of selenium

    Energy Technology Data Exchange (ETDEWEB)

    Spyrou, N.M.; Akanle, O.A.; Dhani, A. (Univ. of Surrey (England))

    1988-01-01

    The essentiality of selenium to the human being and in particular its deficiency state, associated with prolonged inadequate dietary intake, have received considerable attention. In addition, the possible relationship between selenium and cancer and the claim that selenium may possess cancer-prevention properties have focused research effort. It has been observed in a number of studies on laboratory animals that selenium supplementation protects the animals against carcinogen-induced neoplastic growth in various organ sites, reduces the incidence of spontaneous mammary tumors, and suppresses the growth of transplanted tumor cells. In these research programs on the relationship between trace element levels and senile dementia and depression and the elemental changes in blood associated with selenium supplementation in a normal group of volunteers, it became obvious that in addition to establishing normal levels of elements in the population of interest, there was a more fundamental requirement for methods to be developed that would allow the study of the distribution of selenium in the body and its binding sites. The authors propose emission tomography and perturbed angular correlation as techniques worth exploring.

  9. Selenium biochemistry and its role for human health.

    Science.gov (United States)

    Roman, Marco; Jitaru, Petru; Barbante, Carlo

    2014-01-01

    Despite its very low level in humans, selenium plays an important and unique role among the (semi)metal trace essential elements because it is the only one for which incorporation into proteins is genetically encoded, as the constitutive part of the 21st amino acid, selenocysteine. Twenty-five selenoproteins have been identified so far in the human proteome. The biological functions of some of them are still unknown, whereas for others there is evidence for a role in antioxidant defence, redox state regulation and a wide variety of specific metabolic pathways. In relation to these functions, the selenoproteins emerged in recent years as possible biomarkers of several diseases such as diabetes and several forms of cancer. Comprehension of the selenium biochemical pathways under normal physiological conditions is therefore an important requisite to elucidate its preventing/therapeutic effect for human diseases. This review summarizes the most recent findings on the biochemistry of active selenium species in humans, and addresses the latest evidence on the link between selenium intake, selenoproteins functionality and beneficial health effects. Primary emphasis is given to the interpretation of biochemical mechanisms rather than epidemiological/observational data. In this context, the review includes the following sections: (1) brief introduction; (2) general nutritional aspects of selenium; (3) global view of selenium metabolic routes; (4) detailed characterization of all human selenoproteins; (5) detailed discussion of the relation between selenoproteins and a variety of human diseases.

  10. Selenium concentrations of selected medicinal and aromatic plants in Turkey.

    Science.gov (United States)

    Ozkutlu, Faruk; Sekeroglu, Nazim; Koca, Ufuk; Yazici, Gizem

    2011-10-01

    Recent scientific studies have proven the importance of trace elements on human health. The main food supplies are plants and animals, which are significant sources of these minerals. Studies on determining mineral compositions of herbs, spices and some other crops have increased all over the world. Published works revealed that spices, herbs and medicinal plants should be consumed to obtain beneficial trace elements. Selenium (Se), one of the most vital trace elements, has a significant role in human diet acting as a preventative agent against some serious illnesses. Despite numerous scientific works on mineral compositions of medicinal and aromatic plants, investigations of selenium content in these foods could not be successfully studied until recently due to the lack of suitable analytical methods for selenium analysis. Thus, publications on selenium concentrations of foods are recent. In this regard, selenium contents of some medicinal and aromatic plants commonly used as spices, herbal teas and traditional medicines in Turkey were studied in the present research. Selenium contents of the most used parts of these plants were analyzed by ICP-OES (Varian Vista-Pro, Australia). Of the analyzed 26 medicinal and aromatic plants, the highest Se concentration (1133 microg kg-1) was found in sweet basil (Ocimum basilicum L.) and the lowest in sumac (Rhus coriaria L.) fruits (11 microg kg(-1)).

  11. Selenium suppresses leukemia through the action of endogenous eicosanoids.

    Science.gov (United States)

    Gandhi, Ujjawal H; Kaushal, Naveen; Hegde, Shailaja; Finch, Emily R; Kudva, Avinash K; Kennett, Mary J; Jordan, Craig T; Paulson, Robert F; Prabhu, K Sandeep

    2014-07-15

    Eradicating cancer stem-like cells (CSC) may be essential to fully eradicate cancer. Metabolic changes in CSC could hold a key to their targeting. Here, we report that the dietary micronutrient selenium can trigger apoptosis of CSC derived from chronic or acute myelogenous leukemias when administered at supraphysiologic but nontoxic doses. In leukemia CSC, selenium treatment activated ATM-p53-dependent apoptosis accompanied by increased intracellular levels of reactive oxygen species. Importantly, the same treatment did not trigger apoptosis in hematopoietic stem cells. Serial transplantation studies with BCR-ABL-expressing CSC revealed that the selenium status in mice was a key determinant of CSC survival. Selenium action relied upon the endogenous production of the cyclooxygenase-derived prostaglandins Δ(12)-PGJ2 and 15d-PGJ2. Accordingly, nonsteroidal anti-inflammatory drugs and NADPH oxidase inhibitors abrogated the ability of selenium to trigger apoptosis in leukemia CSC. Our results reveal how selenium-dependent modulation of arachidonic acid metabolism can be directed to trigger apoptosis of primary human and murine CSC in leukemia. ©2014 American Association for Cancer Research.

  12. Determinants of selenium status in healthy adults

    Science.gov (United States)

    2011-01-01

    Background Selenium (Se) status in non-deficient subjects is typically assessed by the Se contents of plasma/serum. That pool comprises two functional, specific selenoprotein components and at least one non-functional, non-specific components which respond differently to changes in Se intake. A more informative means of characterizing Se status in non-deficient individuals is needed. Methods Multiple biomarkers of Se status (plasma Se, serum selenoprotein P [SEPP1], plasma glutathione peroxidase activity [GPX3], buccal cell Se, urinary Se) were evaluated in relation to selenoprotein genotypes (GPX1, GPX3, SEPP1, SEP15), dietary Se intake, and parameters of single-carbon metabolism in a cohort of healthy, non-Se-deficient men (n = 106) and women (n = 155). Conclusions Plasma Se concentration was 142.0 ± 23.5 ng/ml, with GPX3 and serum-derived SEPP1 calculated to comprise 20% and 34%, respectively, of that total. The balance, comprised of non-specific components, accounted for virtually all of the interindividual variation in total plasma Se. Buccal cell Se was associated with age and plasma homocysteine (hCys), but not plasma Se. SEPP1 showed a quadratic relationship with body mass index, peaking at BMI 25-30. Urinary Se was greater in women than men, and was associated with metabolic body weight (kg0.75), plasma folate, vitamin B12 and hCys (negatively). One GPX1 genotype (679T/T) was associated with significantly lower plasma Se levels than other allelic variants. Selenium intake, estimated from food frequency questionnaires, did not predict Se status as indicated by any biomarker. These results show that genotype, methyl-group status and BMI contribute to variation in Se biomarkers in Se-adequate individuals. PMID:21767397

  13. Determinants of selenium status in healthy adults

    Directory of Open Access Journals (Sweden)

    Hoeg Antonia

    2011-07-01

    Full Text Available Abstract Background Selenium (Se status in non-deficient subjects is typically assessed by the Se contents of plasma/serum. That pool comprises two functional, specific selenoprotein components and at least one non-functional, non-specific components which respond differently to changes in Se intake. A more informative means of characterizing Se status in non-deficient individuals is needed. Methods Multiple biomarkers of Se status (plasma Se, serum selenoprotein P [SEPP1], plasma glutathione peroxidase activity [GPX3], buccal cell Se, urinary Se were evaluated in relation to selenoprotein genotypes (GPX1, GPX3, SEPP1, SEP15, dietary Se intake, and parameters of single-carbon metabolism in a cohort of healthy, non-Se-deficient men (n = 106 and women (n = 155. Conclusions Plasma Se concentration was 142.0 ± 23.5 ng/ml, with GPX3 and serum-derived SEPP1 calculated to comprise 20% and 34%, respectively, of that total. The balance, comprised of non-specific components, accounted for virtually all of the interindividual variation in total plasma Se. Buccal cell Se was associated with age and plasma homocysteine (hCys, but not plasma Se. SEPP1 showed a quadratic relationship with body mass index, peaking at BMI 25-30. Urinary Se was greater in women than men, and was associated with metabolic body weight (kg0.75, plasma folate, vitamin B12 and hCys (negatively. One GPX1 genotype (679T/T was associated with significantly lower plasma Se levels than other allelic variants. Selenium intake, estimated from food frequency questionnaires, did not predict Se status as indicated by any biomarker. These results show that genotype, methyl-group status and BMI contribute to variation in Se biomarkers in Se-adequate individuals.

  14. Copper and selenium supplementation in the diet of Brangus steers on the nutritional characteristics of meat

    Directory of Open Access Journals (Sweden)

    Arlindo Saran Netto

    2013-01-01

    Full Text Available Twenty-eight Brangus cattle were used to determine the effect of copper and selenium supplementation on the carcass characteristics, fatty acid composition of the longissimus dorsi muscle and on the copper and selenium concentrations in the liver. The treatments were: no supplementation of copper or selenium; 2 mg Se/kg DM as sodium selenite; 40 mg Cu/kg DM as copper sulfate; and 2 mg Se/kg DM as sodium selenite and 40 mg Cu/kg DM as copper sulfate. The fat thickness, rib eye area and fatty acid composition of the longissimus dorsi muscle were not affected by treatments. There was no effect on carcass yield and cooling loss with the supplementation of copper, selenium or selenium × copper in the levels studied. For the ether extract concentration in the longissimus dorsi muscle, no differences were found according to the treatments with selenium, copper or selenium × copper. The treatments with selenium and selenium × copper showed higher selenium concentrations in the liver than the control and copper treatments. For the copper concentration in the liver, the copper and selenium × copper treatments showed higher values than the control and selenium treatments. Despite the little effect on the meat composition, the results of this experiment demonstrate no interaction between selenium and copper in the levels studied.

  15. Selenium status in a group of schoolchildren from the region of Madrid, Spain.

    Science.gov (United States)

    Navia, B; Ortega, R M; Perea, J M; Aparicio, A; López-Sobaler, A M; Rodríguez-Rodríguez, E

    2014-04-01

    To assess the selenium status of a group of schoolchildren from the Region of Madrid, Spain. Study subjects comprised 483 children (216 boys and 267 girls) aged between 8 and 13 years. Selenium intake was determined using a 3-day food record. The foods consumed were transformed into energy and nutrients, and the selenium intake was compared with that recommended. Serum selenium levels were also recorded. Mean (SD) selenium intake [91.0 (25.2) μg day(-1) ] was above the recommended level in 99.4% of subjects; the main dietary sources were cereals, meats, fish and milk products. The serum selenium concentration [mean (SD) 71.1 (14.4) μg L(-1) ], however, was selenium concentration correlated with the selenium intake (r = 0.169; P selenium concentration of selenium intakes than those with a serum concentration of ≥75 μg L(-1) . Although selenium intake was generally above that recommended, the serum selenium concentration of the children could be improved. This could be achieved by increasing the relative consumption of cereals and other selenium rich foods such as fish. © 2013 The Authors Journal of Human Nutrition and Dietetics © 2013 The British Dietetic Association Ltd.

  16. Young children with excess of weight show an impaired selenium status.

    Science.gov (United States)

    Ortega, Rosa M; Rodríguez-Rodríguez, Elena; Aparicio, Aránzazu; Jiménez-Ortega, Ana Isabel; Palmeros, Carolina; Perea, José Miguel; Navia, Beatriz; López-Sobaler, Ana María

    2012-04-01

    People who are overweight/obese commonly experience poorer antioxidant protection. The aim of the present study was to determine whether overweight/obesity is associated with children's selenium status. The study subjects were 573 Madrid schoolchildren aged 8 - 13 years. Their selenium intake was monitored via a three-day food record. Serum selenium concentration and blood glutathione peroxidase (GPx) activity of each subject was also determined, as was body mass index (BMI). Children with excess of weight (BMI>P85) had lower serum selenium concentrations than those of normal weight (64.6 ± 16.8 µg/L compared to 75.3 ± 12.2 µg/L; p selenium intake was also lower (1.99 ± 0.62 µg/kg compared to 2.73 ± 0.88 µg/kg; p selenium and selenium intake (the best being obtained when intake was measured in µg/kg/day, r = 0.338, p selenium and all the anthropometric variables recorded (the strongest correlation was seen between serum selenium and BMI, r = -0.390, p selenium deficiency (selenium intake [OR = 0.9862 (0.9775 - 0.9949)] and age [OR = 0.6813 (0.5434 - 0.8542)] (p selenium and GPx activity (r = 0.177; p selenium status than children of normal weight, which can contribute to poor antioxidant protection. This situation could be more evident in children with central adiposity.

  17. Comparison of selenium distribution in mice organs after the supplementation with inorganic and organic selenium compound selenosemicarbazide.

    Science.gov (United States)

    Musik, Irena; Kozioł-Montewka, Maria; Toś-Luty, Sabina; Donica, Helena; Pasternak, Kazimierz; Wawrzycki, Sławomir

    2002-01-01

    Studies on selenium organ content and its function in living organisms just like studies on other elements provide interesting results although their interpretation is not always clear. The aim of our study was to determine the concentration and distribution of selenium in several organs and tissues in mice after supplementation with our newly synthesized organic compound of selenium selenosemicarbazide (4-o-tolyl-selenosemicarbazide of o-chlorobenzoic acid) as compared to the effects of the supplementation with inorganic compounds. SWISS mice were fed with both types of compounds at the dose of 10(-3) g Se per kg for the period of 10 days. The concentrations of selenium in brains of mice treated with selenocarbazide and sodium selenite were higher than in controls (38.04 micrograms g-1 and 32.00 micrograms g-1 vs. 26.18 micrograms g-1). There was a statistically significant increase in the selenium contents in lungs after supplementation with selenosemicarbazide and sodium selenite (11.81 micrograms g-1 and 6.79 micrograms g-1 vs. 1.75 micrograms g-1 in controls). We found a statistically insignificant increase in selenium contents in intercostal muscles after supplementation with inorganic selenium compounds and a statistically significant increase after the supplementation with selenosemicarbazide (10.13 micrograms g-1; 14.21 micrograms g-1 and 28.84 micrograms g-1, respectively). Our investigations lead to a conclusion that 4-o-tolyl-seleno-semicarbazide of o-chlorobenzoic acid, an organic selenium compound may be more easily absorbed than inorganic sodium IV selenite.

  18. Yeast Infections: MedlinePlus Health Topic

    Science.gov (United States)

    ... Vaginal yeast infection (Medical Encyclopedia) Also in Spanish Topic Image MedlinePlus Email Updates Get Yeast Infections updates ... gram stain Thrush Vaginal yeast infection Related Health Topics Fungal Infections Vaginitis National Institutes of Health The ...

  19. Dietary Selenium Supplementation Modulates Growth of Brain Metastatic Tumors and Changes the Expression of Adhesion Molecules in Brain Microvessels.

    Science.gov (United States)

    Wrobel, Jagoda K; Wolff, Gretchen; Xiao, Rijin; Power, Ronan F; Toborek, Michal

    2016-08-01

    Various dietary agents can modulate tumor invasiveness. The current study explored whether selenoglycoproteins (SeGPs) extracted from selenium-enriched yeast affect tumor cell homing and growth in the brain. Mice were fed diets enriched with specific SeGPs (SeGP40 or SeGP65, 1 mg/kg Se each), glycoproteins (GP40 or GP65, 0.2-0.3 mg/kg Se each) or a control diet (0.2-0.3 mg/kg Se) for 12 weeks. Then, murine Lewis lung carcinoma cells were infused into the brain circulation. Analyses were performed at early (48 h) and late stages (3 weeks) post tumor cell infusion. Imaging of tumor progression in the brain revealed that mice fed SeGP65-enriched diet displayed diminished metastatic tumor growth, fewer extravasating tumor cells and smaller metastatic lesions. While administration of tumor cells resulted in a significant upregulation of adhesion molecules in the early stage of tumor progression, overexpression of VCAM-1 (vascular call adhesion molecule-1) and ALCAM (activated leukocyte cell adhesion molecule) messenger RNA (mRNA) was diminished in SeGP65 supplemented mice. Additionally, mice fed SeGP65 showed decreased expression of acetylated NF-κB p65, 48 h post tumor cell infusion. The results indicate that tumor progression in the brain can be modulated by specific SeGPs. Selenium-containing compounds were more effective than their glycoprotein controls, implicating selenium as a potential negative regulator of metastatic process.

  20. Yeast modulation of human dendritic cell cytokine secretion: an in vitro study.

    Directory of Open Access Journals (Sweden)

    Ida M Smith

    Full Text Available Probiotics are live microorganisms which when administered in adequate amounts confer a health benefit on the host. The concept of individual microorganisms influencing the makeup of T cell subsets via interactions with intestinal dendritic cells (DCs appears to constitute the foundation for immunoregulatory effects of probiotics, and several studies have reported probiotic strains resulting in reduction of intestinal inflammation through modulation of DC function. Consequent to a focus on Saccharomyces boulardii as the fundamental probiotic yeast, very little is known about hundreds of non-Saccharomyces yeasts in terms of their interaction with the human gastrointestinal immune system. The aim of the present study was to evaluate 170 yeast strains representing 75 diverse species for modulation of inflammatory cytokine secretion by human DCs in vitro, as compared to cytokine responses induced by a S. boulardii reference strain with probiotic properties documented in clinical trials. Furthermore, we investigated whether cytokine inducing interactions between yeasts and human DCs are dependent upon yeast viability or rather a product of membrane interactions regardless of yeast metabolic function. We demonstrate high diversity in yeast induced cytokine profiles and employ multivariate data analysis to reveal distinct clustering of yeasts inducing similar cytokine profiles in DCs, highlighting clear species distinction within specific yeast genera. The observed differences in induced DC cytokine profiles add to the currently very limited knowledge of the cross-talk between yeasts and human immune cells and provide a foundation for selecting yeast strains for further characterization and development toward potentially novel yeast probiotics. Additionally, we present data to support a hypothesis that the interaction between yeasts and human DCs does not solely depend on yeast viability, a concept which may suggest a need for further classifications

  1. Paraphyly and (yeast) classification.

    Science.gov (United States)

    Lachance, Marc-André

    2016-12-01

    Yeast systematics has wholeheartedly embraced the phylogenetic approach. Central to this has been the unspoken convention that taxa at all ranks be strictly monophyletic. This can result in a proliferation of small genera and instances of nomenclatural instability, counter to the expected benefit of phylogenetic systematics. But the literature abounds with examples, at all taxonomic levels, where paraphyly is a reality that can no longer be ignored. The very concepts of Bacteria or Archaea, under the constraint of monophyly, are in peril. It is therefore desirable to effect a shift in practices that will recognize the existence of paraphyletic taxa.

  2. Selenium and vitamin E for prostate cancer: post-SELECT (Selenium and Vitamin E Cancer Prevention Trial) status.

    Science.gov (United States)

    Ledesma, Mark C; Jung-Hynes, Brittney; Schmit, Travis L; Kumar, Raj; Mukhtar, Hasan; Ahmad, Nihal

    2011-01-01

    Various formulations of selenium and vitamin E, both essential human dietary components, have been shown to possess a therapeutic and preventive effect against prostate cancer. Fortuitous results of clinical trials also implied a risk-reduction effect of selenium and vitamin E supplements. The Selenium and Vitamin E Cancer Prevention Trial (SELECT), using oral selenium and vitamin E supplementation in disease-free volunteers, was designed to test a prostate cancer chemoprevention hypothesis. SELECT was terminated early because of both safety concerns and negative data for the formulations and doses given. Here, we review and discuss the studies done before and since the inception of SELECT, as well as the parameters of the trial itself. We believe that there is a lack of appropriate in vivo preclinical studies on selenium and vitamin E despite many promising in vitro studies on these agents. It seems that the most effective doses and formulations of these agents for prostate cancer chemoprevention have yet to be tested. Also, improved understanding of selenium and vitamin E biology may facilitate the discovery of these doses and formulations.

  3. Effect of chronic selenium exposure on the freshwater bivalve Corbicula fluminea

    Energy Technology Data Exchange (ETDEWEB)

    Fournier, E.; Adam, C.; Massabuau, J.C.; Garnier-Laplace, J. [CEA Cadarache (DEI/SECRE/LRE), Laboratory of Radioecology and Ecotoxicology, Institute for Radioprotection and Nuclear Safety, 13 - Saint-Paul-lez-Durance (France)

    2004-07-01

    Selenium is essential for most of living organisms. In oxic to moderately oxic fresh-waters, Se exists predominantly in the (+VI) and (+IV) oxidation states as selenate (SeO{sub 4}{sup 2-}) and selenite (SeO{sub 3}{sup 2-}) respectively, whereas in the biota it is incorporated as Se(-II) into seleno-proteins or amino-acids, or as elemental selenium Se(0). At low concentrations, it acts against oxidative damages mainly as the glutathione peroxidase seleno-dependant, but it may be toxic at higher levels (for example, by replacing sulphur in important biomolecules). In filter feeders, such as the freshwater bivalve Corbicula fluminea, selected as biological model, the ventilation activity is a primary limiting step that controls the water influx and therefore the delivery of contaminants. Consequently, a series of short-term experiments were performed to study the effects of different dissolved Se concentrations and forms (selenite; selenate; selenomethionine) on the ventilation activity of Corbicula fluminea and Se tissular distribution. The modification of the ventilation activity of the Se-exposed groups, in comparison to this of reference groups (not exposed to Se) varied greatly according to the form and the concentrations of the Se used. Se concentrations in tissues indicated that selenite was the less bioavailable form whereas selenomethionine displayed the opposite trend. On the basis of this set of experiments, a limited number of conditions have been selected to provide highly contrasting ventilation flow rates and selenium bioaccumulation levels, in order to study the effects of long term exposures, i) at the molecular level, by measuring bio-markers of oxidative stress (forms of glutathione, glutathione peroxidase, glutathione reductase, superoxide dismutase, catalase, and bio-marker of genotoxicity (comet assay), ii) at the (sub)cellular level by analysing Se micro-localisation in target organs and iii) at the individual level by monitoring the variation

  4. Selenium speciation in malt, wort, and beer made from selenium-biofortified two-rowed barley grain.

    Science.gov (United States)

    Rodrigo, Sara; Santamaria, Oscar; Chen, Yi; McGrath, Steve P; Poblaciones, Maria J

    2014-06-25

    Selenium (Se) biofortification of barley is a suitable strategy to increase the Se concentration in grain. In the present paper, the suitability of this Se-biofortified grain for making Se-enriched beer is analyzed. The aim of the present study was to evaluate the effect of different Se fertilizer doses (0, 10, and 20 g of Se ha(-1)) and forms (sodium selenate or sodium selenite) on the Se loss during the malting and brewing processes and Se speciation in grain, malt, wort, and beer. Samples were analyzed using inductively coupled plasma-mass spectrometry (ICP-MS) and high-performance liquid chromatography (HPLC)-ICP-MS for total Se and speciation. Mashing-lautering was the process with the greatest Se loss (83.8%). After malting and brewing, only 7.3% of the initial Se was retained in beer, mainly in selenite form. Even so, the fertilizer application of sodium selenate at 20 g ha(-1) increased the total Se concentration almost 6-fold in the final beer in comparison to the use of grain derived from unfertilized barley. The present paper provides evidence that the use of Se-biofortified barley grain as a raw material to produce Se-enriched beer is possible, and the results are comparable to other methods in terms of efficiency.

  5. Inheritance of the yeast mitochondrial genome

    DEFF Research Database (Denmark)

    Piskur, Jure

    1994-01-01

    Mitochondrion, extrachromosomal genetics, intergenic sequences, genome size, mitochondrial DNA, petite mutation, yeast......Mitochondrion, extrachromosomal genetics, intergenic sequences, genome size, mitochondrial DNA, petite mutation, yeast...

  6. Effect of selenium deficiency on the antioxidative status and muscle damage in growing turkeys.

    Science.gov (United States)

    Fischer, Julia; Bosse, Astrid; Pallauf, Josef

    2008-12-01

    An experiment investigated the effect of different selenium supplementations on the antioxidant defence system and on the occurrence of muscle dystrophy in growing turkeys. Newly hatched male turkeys (B.U.T. Big 6) were divided into eight groups of 18 turkeys each and fed either a basal diet (selenium Vitamin E was adequately supplemented in all diets. After 35 days, muscle damage parameters including aspartate aminotransferase, creatine kinase, creatine kinase M and B were significantly increased in the selenium deficient Group I. A significant reduction of weight gain, feed consumption and selenium dependent glutathione peroxidase activity was also observed in the liver of selenium deficient birds. The ratio of oxidised glutathione (GSSG) to total glutathione (tGSH) was substantially altered in the selenium deficient Group I as well as in Group II (0.10 mg selenium/kg feed). The activity of glutathione reductase (GR) and glutathione-S-transferase (GST) was not affected by selenium deficiency.

  7. Final report on biogeochemical cycling of selenium in Benton Lake, Montana

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The biogeochemical cycling of selenium in Benton Lake National Wildlife Refuge, west-central Montana was very complicated. Selenium accumulation in sediment was a...

  8. Bioavailable nanoparticles obtained in laser ablation of a selenium target in water

    Science.gov (United States)

    Kuzmin, P. G.; Shafeev, Georgii A.; Voronov, Valerii V.; Raspopov, R. V.; Arianova, E. A.; Trushina, E. N.; Gmoshinskii, I. V.; Khotimchenko, S. A.

    2012-11-01

    The process of producing colloidal solutions of selenium nanoparticles in water using the laser ablation method is described. The prospects of using nanoparticles of elementary selenium as a nutrition source of this microelement are discussed.

  9. Bioavailable nanoparticles obtained in laser ablation of a selenium target in water

    Energy Technology Data Exchange (ETDEWEB)

    Kuzmin, P G; Shafeev, Georgii A; Voronov, Valerii V; Raspopov, R V; Arianova, E A; Trushina, E N; Gmoshinskii, I V; Khotimchenko, S A

    2012-11-30

    The process of producing colloidal solutions of selenium nanoparticles in water using the laser ablation method is described. The prospects of using nanoparticles of elementary selenium as a nutrition source of this microelement are discussed. (nanoparticles)

  10. Update to hazard assessment of selenium contamination at Benton Lake National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report summarizes a study done to assess selenium levels on Benton Lake NWR. Water was sampled for dissolved selenium in Lake Creek at the point where it enters...

  11. Update to hazard assessment of selenium contamination at Benton Lake National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The levels of selenium in all trophic levels in Unit 1 on the refuge continue to be a concern. The mean concentration of selenium in water, sediment,...

  12. Transformation of Selenium-Containing Phases in Copper Anode Slimes During Leaching

    Science.gov (United States)

    Li, Xue Jiao; Yang, Hong Ying; Jin, Zhe Nan; Chen, Guo Bao; Tong, Lin Lin

    2017-10-01

    The transformation of selenium-containing phases in copper anode slimes during the leaching process was investigated based on the Eh-pH diagram, leaching efficiencies of metals, and characterization of the residues produced during leaching. The leaching efficiency of selenium increases slowly to 17.7% in the first 50 min and then more rapidly to 98.3% in the next 110 min. The Eh-pH diagram indicates that elemental selenium is an intermediate product of the oxidation of selenide to selenite. The x-ray powder diffraction data and scanning electron microscopy-energy-dispersive x-ray spectroscopy data demonstrate that selenium leaching can be divided into three stages. Ag-Cu selenide first transforms into silver selenide and then converts to elemental selenium. Finally, elemental selenium is dissolved as selenite. The intermediate product, elemental selenium, is the main reason for the slow initial leaching rate of selenium.

  13. Yeasts preservation: alternatives for lyophilisation

    NARCIS (Netherlands)

    Nyanga, L.K.; Nout, M.J.R.; Smid, E.J.; Boekhout, T.; Zwietering, M.H.

    2012-01-01

    The aim of the study was to compare the effect of two low-cost, low technology traditional methods for drying starter cultures with standard lyophilisation. Lyophilised yeast cultures and yeast cultures preserved in dry rice cakes and dry plant fibre strands were examined for viable cell counts

  14. Sociobiology of the budding yeast

    Indian Academy of Sciences (India)

    ... the unicellular yeast Saccharomyces cerevisiae, for sociobiological research. I discuss the problems connected with clear classification of yeast behaviour based on the fitness-based Hamilton paradigm. Relevant traits include different types of communities, production of flocculins, invertase and toxins, and the presence ...

  15. [Blood selenium in healthy persons and individuals with malignant diseases].

    Science.gov (United States)

    Backović, D; Stamenić, V; Marmut, Z; Jorga, J

    1998-01-01

    Preliminary researches taken part in Yugoslavia showed the risky low concentration of selenium in soil, food items and in serum of the examined population [10]. This research was carried out to discover the some factors which could influence the relationship of serum selenium concentration and the appearance of malignant diseases. The investigation was carried out in two Belgrade communities, one rural (Barajevo), and the other central (Stari Grad), in two groups: cancer patients (57 + 17) and healthy controls (41 + 13). These groups were similar in median age and gender. Samples of human serum were obtained by venepunction, and after wet digestion selenium concentration was determined by hydride generated AAS (Perkin-Elmer 5000). Anamnestic data concerning family history of malignancy and comorbidity, especially chronic noncommunicable diseases, were collected by questionnaire. All the participants were asked about their health related habits like: cigarette smoking and alcohol consumption. Dietary habits were assessed by food frequency method. Body mass index (BMI) was calculated as the parameter of nutritional status. The mean serum selenium level in cancer patients and healthy control (Table 1) were not significantly different. But, both cancer patients and healthy controls from Barajevo have significantly lower values comparing to those living in Stari Grad. Table 2 shows the relationship between serum selenium level and various environmental factors. The factors identified as the most important are: living in community Barajevo, age, history of chronic disease and some dietary factors. The univariate analysis (Table 3) revealed that factors like cigarette smoking, alcohol consumption, family history of malignancy and comorbid states were not important predictive factors for patient malignant disease. The multivariate analysis revealed that consumption of sugar, fat and fruit were of the highest predictive value in assessing cancer relative risk. The results

  16. Mitochondria autophagy in yeast.

    Science.gov (United States)

    Kanki, Tomotake; Klionsky, Daniel J; Okamoto, Koji

    2011-05-15

    The mitochondrion is an organelle that carries out a number of important metabolic processes such as fatty acid oxidation, the citric acid cycle, and oxidative phosphorylation. However, this multitasking organelle also generates reactive oxygen species (ROS), which can cause oxidative stress resulting in self-damage. This type of mitochondrial damage can lead to the further production of ROS and a resulting downward spiral with regard to mitochondrial capability. This is extremely problematic because the accumulation of dysfunctional mitochondria is related to aging, cancer, and neurodegenerative diseases. Accordingly, appropriate quality control of this organelle is important to maintain proper cellular homeostasis. It has been thought that selective mitochondria autophagy (mitophagy) contributes to the maintenance of mitochondrial quality by eliminating damaged or excess mitochondria, although little is known about the mechanism. Recent studies in yeast identified several mitophagy-related proteins, which have been characterized with regard to their function and regulation. In this article, we review recent advances in the physiology and molecular mechanism of mitophagy and discuss the similarities and differences of this degradation process between yeast and mammalian cells.

  17. Production of Food Grade Yeasts

    Directory of Open Access Journals (Sweden)

    Argyro Bekatorou

    2006-01-01

    Full Text Available Yeasts have been known to humans for thousands of years as they have been used in traditional fermentation processes like wine, beer and bread making. Today, yeasts are also used as alternative sources of high nutritional value proteins, enzymes and vitamins, and have numerous applications in the health food industry as food additives, conditioners and flavouring agents, for the production of microbiology media and extracts, as well as livestock feeds. Modern scientific advances allow the isolation, construction and industrial production of new yeast strains to satisfy the specific demands of the food industry. Types of commercial food grade yeasts, industrial production processes and raw materials are highlighted. Aspects of yeast metabolism, with respect to carbohydrate utilization, nutritional aspects and recent research advances are also discussed.

  18. Red yeast rice for dysipidemia.

    Science.gov (United States)

    Shamim, Shariq; Al Badarin, Firas J; DiNicolantonio, James J; Lavie, Carl J; O'Keefe, James H

    2013-01-01

    Red yeast rice is an ancient Chinese food product that contains monacolins, chemical substances that are similar to statins in their mechanisms of action and lipid lowering properties. Several studies have found red yeast rice to be moderately effective at improving the lipid profile, particularly for lowering the low-density lipoprotein cholesterol levels. One large randomized controlled study from China found that red yeast rice significantly improved risk of major adverse cardiovascular events and overall survival in patients following myocardial infarction. Thus, red yeast rice is a potentially useful over-the-counter cholesterol-lowering agent. However, many red yeast rice formulations are non-standardized and unregulated food supplements, and there is a need for further research and regulation of production.

  19. Evolutionary History of Ascomyceteous Yeasts

    Energy Technology Data Exchange (ETDEWEB)

    Haridas, Sajeet; Riley, Robert; Salamov, Asaf; Goker, Markus; Klenk, Hans-Peter; Kurtzman, Cletus P.; Blackwell, Meredith; Grigoriev, Igor; Jeffries, Thomas W.

    2014-06-06

    Yeasts are important for many industrial and biotechnological processes and show remarkable diversity despite morphological similarities. We have sequenced the genomes of 16 ascomycete yeasts of taxonomic and industrial importance including members of Saccharomycotina and Taphrinomycotina. A comparison of these with several other previously published yeast genomes have added increased confidence to the phylogenetic positions of previously poorly placed species including Saitoella complicata, Babjeviella inositovora and Metschnikowia bicuspidata. Phylogenetic analysis also showed that yeasts with alternative nuclear codon usage where CUG encodes serine instead of leucine are monophyletic within the Saccharomycotina. Most of the yeasts have compact genomes with a large fraction of single exon genes with Lipomyces starkeyi and the previously published Pneumocystis jirovecii being notable exceptions. Intron analysis suggests that early diverging species have more introns. We also observed a large number of unclassified lineage specific non-simple repeats in these genomes.

  20. Treating chronic arsenic toxicity with high selenium lentil diets

    Energy Technology Data Exchange (ETDEWEB)

    Sah, Shweta [Department of Ecosystem and Public Health, Faculty of Medicine, University of Calgary, Calgary, AB T2N 4Z6 (Canada); Vandenberg, Albert [Department of Plant Sciences, University of Saskatchewan, Saskatoon, SK S7N 5A8 (Canada); Smits, Judit, E-mail: judit.smits@ucalgary.ca [Department of Ecosystem and Public Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB T2N 4Z6 (Canada)

    2013-10-01

    Arsenic (As) toxicity causes serious health problems in humans, especially in the Indo-Gangetic plains and mountainous areas of China. Selenium (Se), an essential micronutrient is a potential mitigator of As toxicity due to its antioxidant and antagonistic properties. Selenium is seriously deficient in soils world-wide but is present at high, yet non-toxic levels in the great plains of North America. We evaluate the potential of dietary Se in counteracting chronic As toxicity in rats through serum biochemistry, blood glutathione levels, immunotoxicity (antibody response), liver peroxidative stress, thyroid response and As levels in tissues and excreta. To achieve this, we compare diets based on high-Se Saskatchewan (SK) lentils versus low-Se lentils from United States. Rats drank control (0 ppm As) or As (40 ppm As) water while consuming SK lentils (0.3 ppm Se) or northwestern USA lentils (< 0.01 ppm Se) diets for 14 weeks. Rats on high Se diets had higher glutathione levels regardless of As exposure, recovered antibody responses in As-exposed group, higher fecal and urinary As excretion and lower renal As residues. Selenium deficiency caused greater hepatic peroxidative damage in the As exposed animals. Thyroid hormones, triiodothyronine (T3) and thyroxine (T4), were not different. After 14 weeks of As exposure, health indicators in rats improved in response to the high Se lentil diets. Our results indicate that high Se lentils have a potential to mitigate As toxicity in laboratory mammals, which we hope will translate into benefits for As exposed humans. - Highlights: • We reduce chronic arsenic toxicity in rats with a whole food solution. • High selenium lentils decrease liver damage and increase blood glutathione levels. • High selenium lentil diets increase urinary and fecal arsenic excretion. • High selenium lentil diets decrease arsenic levels in kidney, the storage organ. • High selenium lentil diets reverse arsenic suppression of the B cell