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Sample records for biotransformation studies employing

  1. Stereoselective determination of midodrine and desglymidodrine in culture medium: application to a biotransformation study employing endophytic fungi.

    PubMed

    Barth, Thiago; Pupo, Mônica Tallarico; Borges, Keyller Bastos; Okano, Laura Tiemi; Bonato, Pierina Sueli

    2010-05-01

    A CE method was developed and validated for the stereoselective determination of midodrine and desglymidodrine in Czapek culture medium to be applied to a stereoselective biotransformation study employing endophytic fungi. The electrophoretic analyses were performed using an uncoated fused-silica capillary and 70 mmol/L sodium acetate buffer solution (pH 5.0) containing 30 mmol/L heptakis (2, 3, 6-tri-O-methyl)-beta-CD as running electrolyte. The applied voltage and temperature used were 15 kV and 15 degrees C, respectively. The UV detector was set at 200 nm. The sample preparation was carried out by liquid-liquid extraction using ethyl acetate as extractor solvent. The method was linear over the concentration range of 0.1-12 microg/mL for each enantiomer of midodrine and desglymidodrine (r> or =0.9975). Within-day and between-day precision and accuracy evaluated by RSDs and relative errors, respectively, were lower than 15% for all analytes. The method proved to be robust by a fractional factorial design evaluation. The validated method was used to assess the midodrine biotransformation to desglymidodrine by the fungus Phomopsis sp. (TD2), which biotransformed 1.1% of (-)-midodrine to (-)-desglymidodrine and 6.1% of (+)-midodrine to (+)-desglymidodrine.

  2. Enantioselective analysis of oxybutynin and N-desethyloxybutynin with application to an in vitro biotransformation study.

    PubMed

    da Fonseca, Patrícia; de Freitas, Luis Alexandre Pedro; Pinto, Luis Felipe Ribeiro; Pestana, Cezar Rangel; Bonato, Pierina Sueli

    2008-11-01

    An enantioselective method using liquid-phase microextraction (LPME) followed by HPLC analysis was developed for the determination of oxybutynin (OXY) and its major metabolite N-desethyloxybutynin (DEO) in rat liver microsomal fraction. The LPME procedure was optimized using multifactorial experiments. Under the optimal extraction conditions, the mean recoveries were 61 and 55% for (R)-OXY and (S)-OXY, respectively, and 70 and 76% for (R)-DEO and (S)-DEO, respectively. The validated method was employed to an in vitro biotransformation study using rat liver microsomal fraction. The results demonstrated the enantioselective biotransformation of OXY.

  3. Biotransformation studies of textile dye Remazol Orange 3R.

    PubMed

    Surwase, Swati V; Deshpande, Krutika K; Phugare, Swapnil S; Jadhav, Jyoti P

    2013-08-01

    In the present study, biotransformation of Remazol Orange 3R (RO3R) was studied using well-known bacterial isolate Pseudomonas aeruginosa strain BCH. The dye was decolorized up to 98 % within 15 min. The induction in the level of various oxidoreductive enzymes viz. laccase, tyrosinase, veratryl alcohol oxidase and DCIP reductase were observed in the cells obtained after decolorization of RO3R, which supports their role in decolorization. The metabolites of RO3R obtained after biodegradation were identified and characterized by various analytical techniques viz, HPLC, FTIR, and GC-MS. The RO3R was transformed to the N-(7 amino 8 hydroxy-napthalen-2yl) actamide (m/z, 198), Acetamide (m/z, 59) and Napthalen-1-ol (m/z, 144).

  4. [Studies on biotransformation of arbutin by 4-hydroxy phenol in hairy root of Polygonum multiflorum].

    PubMed

    Yan, Chun-yan; Zhang, Zhang; Yu, Rong-min; Kong, Ling-yi

    2007-02-01

    To study the biotransformation of arbutin by 4-hydroxy phenol in hairy root of Polygonum multiflorum. 4-hydroxy phenol was used as substrate, the standard curve was made by HPLC, and the influences of the co-culture time, the concentration of substrate added and the volume of culture flasks on biotransformation of arbutin were measured by the index of the production yield and transform rate of arbutin. Arbutin could be detected from both of the cultures and medium. The correlation curve of arbutin: Y = 440740X - 1.473 (r = 0.9997). The production yield (2.22 g x L(-1)) and conversion ratio (81.45%) of arbutin reached the maximum amount as co-culture time at 72 h, substrate added in medium for 1100 mg x L(-1). Furthermore a large-scale culture of 3 L was also successful in our experiment. It was firstly to biosynthesis arbutin in hairy root of P. multiflorum. The production yield and trasfer rate of arbutin were increased largely. And large-scale production (3 L culture flask) of arbutin was achieved in the experiment and it would be valuable for the industrial production of arbutin by biotechnological method in the future.

  5. Biotransformation of an uncured composite material

    NASA Technical Reports Server (NTRS)

    Welsh, Clement J.; Glass, Michael J.; Cheslack, Brian; Pryor, Robert; Tran, Duan K.; Bowers-Irons, Gail

    1994-01-01

    The feasibility of biologically degrading prepreg wastes was studied. The work was conducted with the intention of obtaining baseline data that would facilitate the achievement of two long-range goals. These goals are: (1) the biological remediation of the hazardous components in the prepreg wastes, and (2) providing the potential for recycling the prepreg waste fibers. The experiments examined a prepreg that employs an bismaleimide resin system. Initial results demonstrated an obvious deterioration of the prepreg material when incubated with several bacterial strains. The most active cultures were identified as a mixture of 'Bacillus cereus' and 'Pseudomonas sp'. Gas chromatography analyses revealed seven primary compounds in the resin mixture. Biotransformation studies, using the complete prepreg material, demonstrated on obvious loss of all seven organic compounds. Gas chromatography-mass spectrometry analyses resulted in structure assignments for the two primary components of the resin. Both were analogs of Bisphenol A; one being bismaleimide, and the other being Bisphenol A containing a diglycidyl moiety. The 'diglycidyl analog' was purified using thin-layer chromatography and the biotransformation of this compound (at 27 ug/ml bacterial culture) was monitored. After a seven-day incubation, approximately 40% of the organic compound was biotransformed. These results demonstrate the biotransformation of the prepreg resin and indicate that biological remediation of the prepreg wastes is feasible.

  6. Role of biotransformation studies in minimizing metabolism-related liabilities in drug discovery.

    PubMed

    Shu, Yue-Zhong; Johnson, Benjamin M; Yang, Tian J

    2008-01-01

    Metabolism-related liabilities continue to be a major cause of attrition for drug candidates in clinical development. Such problems may arise from the bioactivation of the parent compound to a reactive metabolite capable of modifying biological materials covalently or engaging in redox-cycling reactions leading to the formation of other toxicants. Alternatively, they may result from the formation of a major metabolite with systemic exposure and adverse pharmacological activity. To avert such problems, biotransformation studies are becoming increasingly important in guiding the refinement of a lead series during drug discovery and in characterizing lead candidates prior to clinical evaluation. This article provides an overview of the methods that are used to uncover metabolism-related liabilities in a pre-clinical setting and offers suggestions for reducing such liabilities via the modification of structural features that are used commonly in drug-like molecules.

  7. [Studies on the biotransformation of escin Ia by human intestinal bacteria and the anti-tumor activities of desacylescin I].

    PubMed

    Yang, Xiu-Wei; Zhao, Jing; Cui, Jing-Rong; Guo, Wei

    2004-02-01

    To study Biotransformation of escin Ia by the crude enzymes of human intestinal bacteria and Lactobacillus brevis, determine the structures of biotransformation products and assay the inhibitory effect of desacylescin I on the tumor cell growth. The escin Ia was incubated with crude enzymes of human intestinal bacteria and Lactobacillus brevis in vitro, respectively. The biotransformation products were isolated and purified by the chromatographic methods and the structures were determined by the spectroscopic techniques. Escin Ia was converted into isoescin Ia, desacylescin I, 21beta-O-tigloylprotoaescigenin and protoaescigenin by crude enzymes of human intestinal bacteria and Lactobacillus brevis. Desacylescin I showed potentially inhibitory effects on tumor cell growth of mouse sarcoma-180, hepatic carcinoma H(22) and lung carcinoma in vivo. The results suggest that Escin Ia was a prodrug and its structure can be converted by human intestinal bacteria and Lactobacillus brevis. Desacylescin I as a biotransformation product showed potentially inhibitory effects on mouse tumor, and a potential candidate for anti tumor agents.

  8. Employer Attitudes toward Study Abroad

    ERIC Educational Resources Information Center

    Trooboff, Stevan; Vande Berg, Michael; Rayman, Jack

    2008-01-01

    In recent years, as study abroad professionals have come to focus more squarely on the question of what students are in fact learning abroad, there has been increasing speculation about the extent to which study abroad increases prospects for employability following graduation. Common wisdom has it that undergraduates who study abroad have an…

  9. In-vitro immunomodulatory and anti-cancerous activities of biotransformed products of Dianabol through Azadirachta indica and its molecular docking studies

    PubMed Central

    2013-01-01

    Background Plant Biotransformation is one of the tools for structural modifications of the organic substrate of low, moderate or high biological value utilizing plant cultured cells, these modifications of organic structures may lead to biologically augmented products and which may be ultimately substantial in cure or improvement of various morbidities and diseases. Results Azadirachta indica A. Juss. suspension culture was employed for the biotransformation of dianabol (1) for the first time, and two metabolites, 17β-hydroxy-17α-methyl-5α-androst-1-en-3-one (2), and 17β-hydroxy-17α-methyl-5α-androstan-3-one (3) were obtained. Conclusions Most important aspect of this work was the evaluation of metabolite 2, which strongly and differentially suppressed [not affecting whole blood and human polymorphonuclear cells (PMN)] the phytohemagglutinin (PHA)-activated T-cell proliferation (IC50: <10.33 μM), and also found to inhibit IL-2 production (IC50: 16.89 ± 1.32) unlike metabolite 3 and compound 1. Compound 2 also exhibited anticancer activity against lung cancer cell line; NCI-H460, it moderately inhibited the growth of cancer cells (22.5 ± 4.15 μM). Furthermore, a good correlation between the predicted binding energies of the compounds acquired by the FlexX program and the experimental affinities were speculated upon interacting with IL-2 protein during molecular docking studies. PMID:24764465

  10. Enantioselective Biotransformation of Chiral Persistent Organic Pollutants.

    PubMed

    Zhang, Ying; Ye, Jing; Liu, Min

    2017-01-01

    Enantiomers of chiral compounds commonly undergo enantioselective transformation in most biologically mediated processes. As chiral persistent organic pollutants (POPs) are extensively distributed in the environment, differences between enantiomers in biotransformation should be carefully considered to obtain exact enrichment and specific health risks. This review provides an overview of in vivo biotransformation of chiral POPs currently indicated in the Stockholm Convention and their chiral metabolites. Peer-reviewed journal articles focused on the research question were thoroughly searched. A set of inclusion and exclusion criteria were developed to identify relevant studies. We mainly compared the results from different animal models under controlled laboratory conditions to show the difference between enantiomers in terms of distinct transformation potential. Interactions with enzymes involved in enantioselective biotransformation, especially cytochrome P450 (CYP), were discussed. Further research areas regarding this issue were proposed. Limited evidence for a few POPs has been found in 30 studies. Enantioselective biotransformation of α-hexachlorocyclohexane (α-HCH), chlordane, dichlorodiphenyltrichloroethane (DDT), heptachlor, hexabromocyclododecane (HBCD), polychlorinated biphenyls (PCBs), and toxaphene, has been investigated using laboratory mammal, fish, bird, and worm models. Tissue and excreta distributions, as well as bioaccumulation and elimination kinetics after administration of racemate and pure enantiomers, have been analyzed in these studies. Changes in enantiomeric fractions have been considered as an indicator of enantioselective biotransformation of chiral POPs in most studies. Results of different laboratory animal models revealed that chiral POP biotransformation is seriously affected by chirality. Pronounced results of species-, tissue-, gender-, and individual-dependent differences are observed in in vivo biotransformation of chiral POPs

  11. Biotransformation strategy to reduce allergens in propolis.

    PubMed

    Gardana, Claudio; Barbieri, Andrea; Simonetti, Paolo; Guglielmetti, Simone

    2012-07-01

    Propolis (bee glue) is a resinous, sticky, dark-colored material produced by honeybees. Propolis today, due to its medicinal properties, is increasingly popular and is extensively used in food, beverages, and cosmetic products. Besides its numerous positive properties, propolis may also have adverse effects, such as, principally, allergic eczematous contact dermatitis in apiarists and in consumers with an allergic predisposition. In this study, we found appropriate conditions for removing caffeate esters, which are the main allergenic components, from raw propolis. The proposed method consists of the resuspension of propolis in a food grade solvent, followed by a biotransformation based on the cinnamoyl esterase activity of Lactobacillus helveticus. We showed that the reduction of caffeate esters by L. helveticus did not affect the content of flavonoids, which are the main bioactive molecules of propolis. Furthermore, we verified that the biotransformation of propolis did not cause a loss of antimicrobial activity. Finally, we demonstrated that the ability of L. helveticus to hydrolyze caffeate esters in propolis is strain specific. In conclusion, the proposed strategy is simple, employs food grade materials, and is effective in selectively removing allergenic molecules without affecting the bioactive fraction of propolis. This is the first study demonstrating that the allergenic caffeate esters of propolis can be eliminated by means of a bacterial biotransformation procedure.

  12. Biotransformation Strategy To Reduce Allergens in Propolis

    PubMed Central

    Gardana, Claudio; Barbieri, Andrea; Simonetti, Paolo

    2012-01-01

    Propolis (bee glue) is a resinous, sticky, dark-colored material produced by honeybees. Propolis today, due to its medicinal properties, is increasingly popular and is extensively used in food, beverages, and cosmetic products. Besides its numerous positive properties, propolis may also have adverse effects, such as, principally, allergic eczematous contact dermatitis in apiarists and in consumers with an allergic predisposition. In this study, we found appropriate conditions for removing caffeate esters, which are the main allergenic components, from raw propolis. The proposed method consists of the resuspension of propolis in a food grade solvent, followed by a biotransformation based on the cinnamoyl esterase activity of Lactobacillus helveticus. We showed that the reduction of caffeate esters by L. helveticus did not affect the content of flavonoids, which are the main bioactive molecules of propolis. Furthermore, we verified that the biotransformation of propolis did not cause a loss of antimicrobial activity. Finally, we demonstrated that the ability of L. helveticus to hydrolyze caffeate esters in propolis is strain specific. In conclusion, the proposed strategy is simple, employs food grade materials, and is effective in selectively removing allergenic molecules without affecting the bioactive fraction of propolis. This is the first study demonstrating that the allergenic caffeate esters of propolis can be eliminated by means of a bacterial biotransformation procedure. PMID:22522681

  13. Development of novel valerolactam-benzimidazole hybrids anthelmintic derivatives: Diffusion and biotransformation studies in helminth parasites.

    PubMed

    Munguía, Beatriz; Michelena, Mauricio; Melian, Elisa; Saldaña, Jenny; Ures, Ximena; Manta, Eduardo; Domínguez, Laura

    2015-06-01

    In the search for new anthelmintics able to overcome the resistance problem against all available drugs in livestock, the synthesis of novel valerolactam-benzimidazole hybrid compounds was reported. This allowed us to obtain these in vitro and in vivo bioactive compounds using Nippostrongylus brasiliensis rat model by integrating physiology-based assays and ex vivo diffusion studies. In order to further study those novel hybrid molecules, Haemonchus contortus (a sheep gastrointestinal nematode of interest) and Mesocestoides vogae tetrathyridia (a useful system to study the efficacy of anthelmintic drugs against cestoda) were used as parasite models to compare the ex vivo patterns of diffusion and biotransformation of benzimidazoles and their valerolactam-benzimidazole hybrid derivatives. On average, a nine-fold higher intraparasitic concentration of compounds was found in M. vogae compared with H.contortus, with similarities regarding the order of entry of compounds, highlighting febendazole (FEB) and its hybrid compound 10, while valerolactam compound 2 practically did not penetrate the parasites. Interestingly, sulphoxidation drug metabolism was observed and measured, revealing percentages of oxidation of 8.2% and 14.5% for albendazole (ABZ) and febendazole respectively in M. vogae, while this effect was more relevant in H. contortus parasite. More importantly, significant differences were observed between anthelmintic-susceptible adult parasites (Hc S) and those from sheep farms (Hc U). In fact, the percentages of oxidation of FEB and the hybrid compound 8 were higher in Hc U (25.5%, 54.1%, respectively) than in Hc S (8.8%, 38.2%). Interestingly, sulphoxidation of hybrid compound 10 was neither observed in M. vogae nor in H. contortus parasites, suggesting that increased drug metabolism (oxidation reactions) could not be used by these parasites as a defense mechanism against this novel drug. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Regio- and stereoselectivities in plant cell biotransformation

    SciTech Connect

    Hamada, H.

    1995-12-01

    The ability of plant cultured cells to convert foreign substrates into more useful substances is of considerable interest. Therefore I have studied biotransformation of foreign substrate by plant cell suspension cultures. In this presentation, I report regio- and stereoselectivities in biotransformation of steroids and indole alkaloids and taxol by plant (tobacco, periwinkle, moss, orchid) cell suspension cultures.

  15. Identifying the Correct Biotransformation Model from Polychlorinated Biphenyl and Dioxin Dechlorination Batch Studies

    PubMed Central

    Krumins, Valdis; Fennell, Donna E.

    2014-01-01

    Abstract We performed Monte Carlo simulations of batch transformations of hydrophobic compounds using typical numbers of data points, extent of reaction, and measurement error, to identify the most appropriate biotransformation model to describe such data under different conditions. Highly hydrophobic compounds such as polychlorinated biphenyls (PCBs) and dioxins present special challenges for parameterization due to low environmental concentrations and slow biotransformation rates, which result in high sample variability, few samples, and limited substrate concentration range. Four models of varying complexity (zero-order, first-order, Monod, and Best) were fit to simulated data. Various combinations of initial concentration (S0), half saturation concentration (KS), maximum substrate utilization rate (qmax), measurement error, number of data points per batch run, and extent of biotransformation were simulated. One thousand Monte-Carlo runs were performed for each parameter combination, and AICc (Akaike's information criterion corrected for small numbers of data points) was used to determine the most appropriate model. Neither the Best model nor the zero-order model ever produced the lowest AICc for a majority of simulations under any combination of test conditions. With 10% measurement error, the first-order model always outperformed the others. In the case of 1% measurement error with 10 evenly-spaced data points, the Monod model was the better choice when S0>KS and the system was not mass transfer limited \\documentclass{aastex}\\usepackage{amsbsy}\\usepackage{amsfonts}\\usepackage{amssymb}\\usepackage{bm}\\usepackage{mathrsfs}\\usepackage{pifont}\\usepackage{stmaryrd}\\usepackage{textcomp}\\usepackage{portland, xspace}\\usepackage{amsmath, amsxtra}\\pagestyle{empty}\\DeclareMathSizes{10}{9}{7}{6}\\begin{document} $$(k \\cdot S_{0} > \\frac {1} {5} \\ q_{max});$$ \\end{document} otherwise, the first-order model was indicated. S0 is constrained by the compound

  16. Studies on the microbial biotransformation of the novel psychoactive substance methylenedioxypyrovalerone (MDPV) in wastewater by means of liquid chromatography-high resolution mass spectrometry/mass spectrometry.

    PubMed

    Mardal, Marie; Meyer, Markus R

    2014-09-15

    Sewage profiling as a mean to estimate consumption of drugs of abuse is gaining increasing attention. However, only scarce data are available so far on the impact of microbial biotransformation on the presence and hence detectability of drugs of abuse and their metabolites in wastewater (WW) samples. The aim of this work was therefore to study the biotransformation pathways of the novel psychoactive substance 3,4-methylenedioxypyrovalerone (MPDV) in WW by incubating it, based on the OECD guideline 314 A. MDPV was incubated (100 μg/L) for 10d at 22 °C in WW from a local WW treatment plant. Furthermore, urine and feces collected from rats administered 20mg MDPV/kg BW were incubated correspondingly. Samples were worked-up either by centrifugation/filtration and solid-phase (HCX) extraction or QuEChERS. High resolution (HR) mass spectra (MS) were recorded using an Orbitrap mass spectrometer. All products were identified via their HR-MS(2) spectra and chromatographic properties. The observed biotransformations in WW were: demethylenation and subsequent O-methylation, hydroxylation at the phenyl part, hydroxylation at the pyrrolidine part with subsequent methylation or oxidation, N-demethylation, and hydroxylation at the alkyl part as well as combination of them. In total, 12 biotransformation products were identified after 10 days of incubation. Three of these biotransformation products were previously reported to be also rat and human metabolites. No additional MDPV biotransformation products could be found after incubating the rat urine and feces samples. Instead, the urinary phase II glucuronides were nearly completely cleaved after one day of WW incubation. The presented study indicates that demethylenyl-methyl MDPV, the most abundant metabolite in human urine, should be the best indicator in WW to estimate its use. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Comparative study of different exposure routes on the biotransformation and genotoxicity of PAHs in the flatfish species, Scophthalmus maximus.

    PubMed

    Le Dû-Lacoste, Marie; Akcha, Farida; Dévier, Marie-Hélène; Morin, Bénédicte; Burgeot, Thierry; Budzinski, Hélène

    2013-02-01

    In this study, laboratory experiments were carried out in order to come to a better understanding of the fate of polycyclic aromatic hydrocarbons (PAHs) in the marine environment and especially on their bioaccumulation, biotransformation and genotoxic effects in fish. Juveniles of turbot (Scophthalmus maximus) were exposed to PAHs through different routes via (1) a mixture of dissolved PAHs, (2) a PAH-polluted sediment and (3) an oil fuel elutriate. Fish were exposed 4 days followed by a 6-day depuration period. In each experiment, PAH concentrations in the seawater of the tanks were analysed regularly by gas chromatography coupled with mass spectrometry. Muscle and liver samples were also analysed for parent PAH levels and PAH bioconcentration factors were calculated. Biotransformation was evaluated by measuring the levels of PAH metabolites in fish bile. Genotoxicity was assessed by the alkaline comet assay. Regardless of exposure route, the parent PAH concentrations in the liver and muscle showed a peak level 1 day after the beginning of the exposure, followed by a decrease up to the background level towards the end of the experiment, except for the exposure to dissolved PAHs for which levels were relatively low throughout the study. As a consequence, no bioaccumulation was observed in fish tissues at the end of the experiment. In contrast, regardless of exposure routes, a rapid production of biliary metabolites was observed throughout the whole exposure experiment. This was especially true for 1-hydroxypyrene, the major metabolite of pyrene. After 6 days of recovery in clean water, a significant decrease in the total metabolite concentrations occurred in bile. Fish exposed through either route displayed a significant increase in DNA strand breaks after 4 days of exposure, and significant correlations were observed between the level of biliary PAH metabolites and the level of DNA lesions in fish erythrocytes. Overall results indicate that exposure to either a

  18. Silica ecosystem for synergistic biotransformation

    NASA Astrophysics Data System (ADS)

    Mutlu, Baris R.; Sakkos, Jonathan K.; Yeom, Sujin; Wackett, Lawrence P.; Aksan, Alptekin

    2016-06-01

    Synergistical bacterial species can perform more varied and complex transformations of chemical substances than either species alone, but this is rarely used commercially because of technical difficulties in maintaining mixed cultures. Typical problems with mixed cultures on scale are unrestrained growth of one bacterium, which leads to suboptimal population ratios, and lack of control over bacterial spatial distribution, which leads to inefficient substrate transport. To address these issues, we designed and produced a synthetic ecosystem by co-encapsulation in a silica gel matrix, which enabled precise control of the microbial populations and their microenvironment. As a case study, two greatly different microorganisms: Pseudomonas sp. NCIB 9816 and Synechococcus elongatus PCC 7942 were encapsulated. NCIB 9816 can aerobically biotransform over 100 aromatic hydrocarbons, a feat useful for synthesis of higher value commodity chemicals or environmental remediation. In our system, NCIB 9816 was used for biotransformation of naphthalene (a model substrate) into CO2 and the cyanobacterium PCC 7942 was used to provide the necessary oxygen for the biotransformation reactions via photosynthesis. A mathematical model was constructed to determine the critical cell density parameter to maximize oxygen production, and was then used to maximize the biotransformation rate of the system.

  19. Silica ecosystem for synergistic biotransformation

    PubMed Central

    Mutlu, Baris R.; Sakkos, Jonathan K.; Yeom, Sujin; Wackett, Lawrence P.; Aksan, Alptekin

    2016-01-01

    Synergistical bacterial species can perform more varied and complex transformations of chemical substances than either species alone, but this is rarely used commercially because of technical difficulties in maintaining mixed cultures. Typical problems with mixed cultures on scale are unrestrained growth of one bacterium, which leads to suboptimal population ratios, and lack of control over bacterial spatial distribution, which leads to inefficient substrate transport. To address these issues, we designed and produced a synthetic ecosystem by co-encapsulation in a silica gel matrix, which enabled precise control of the microbial populations and their microenvironment. As a case study, two greatly different microorganisms: Pseudomonas sp. NCIB 9816 and Synechococcus elongatus PCC 7942 were encapsulated. NCIB 9816 can aerobically biotransform over 100 aromatic hydrocarbons, a feat useful for synthesis of higher value commodity chemicals or environmental remediation. In our system, NCIB 9816 was used for biotransformation of naphthalene (a model substrate) into CO2 and the cyanobacterium PCC 7942 was used to provide the necessary oxygen for the biotransformation reactions via photosynthesis. A mathematical model was constructed to determine the critical cell density parameter to maximize oxygen production, and was then used to maximize the biotransformation rate of the system. PMID:27264916

  20. Pharmacokinetic Study of Biotransformation Products from an Anxiolytic Fraction of Tilia americana.

    PubMed

    Juárez Ramírez, Virgilio Alfonso; Jiménez-Beltrán, María Isabel; Zamilpa, Alejandro; Herrera-Ruiz, Maribel; Abarca-Vargas, Rodolfo; Lombardo-Earl, Galia; Tortoriello, Jaime; Jiménez-Ferrer, Enrique

    2017-07-27

    An anxiolytic fraction of Tilia americana standardized in tiliroside, rutin, quercitrin, quercetin glucoside, and kaempferol was obtained. After oral administration of the fraction, the above-mentioned flavonoids were not detected in plasma over 24 h. However, meta and para hydroxyphenylacetic acid and dihydroxyphenylacetic acid (m-HPAA, p-HPAA and DOPAC) were monitored. These are the biotransformation compounds of the aglycones of kaempferol and quercetin; these aglycones are products of the other flavonoids present in the anxiolytic fraction. The analytical methods (HPLC) for flavonoids and the related compounds (m-HPAA, p-HPAA and DOPAC) were validated, determining the parameters of accuracy, precision, specificity or selectivity, limit of detection, quantification range, and robustness. The pharmacokinetic assay was performed with ICR mice strains, which were given 200 mg/kg of the standardized active fraction. The results of validation of the analytical methods were obtained, allowing it to be established in a validated way that no flavonoids present in the anxiolytic fraction of T. americana were detected in plasma. However, detection and follow up was possible for the serum levels of m-HPAA, p-HPAA, and DOPAC. The three compounds follow a two-compartment model with very similar parameters between m-HPAA and p-HPAA, some being different from the ones characterized in the pharmacokinetics of DOPAC.

  1. Mechanism study of sulfur fertilization mediating copper translocation and biotransformation in rice (Oryza sativa L.) plants.

    PubMed

    Sun, Lijuan; Yang, Jianjun; Fang, Huaxiang; Xu, Chen; Peng, Cheng; Huang, Haomin; Lu, Lingli; Duan, Dechao; Zhang, Xiangzhi; Shi, Jiyan

    2017-07-01

    Metabolism of sulfur (S) is suggested to be an important factor for the homeostasis and detoxification of Cu in plants. We investigated the effects of S fertilizers (S(0), Na2SO4) on Cu translocation and biotransformation in rice plants by using multiple synchrotron-based techniques. Fertilization of S increased the biomass and yield of rice plants, as well as the translocation factor of Cu from root to shoot and shoot to grain, resulting in enhanced Cu in grain. Sulfur K-edge X-ray near edge structure (XANES) analysis showed that fertilization of S increased the concentration of glutathione in different rice tissues, especially in rice stem and leaf. Copper K-edge XANES results indicated that a much higher proportion of Cu (I) species existed in rice grain than husk and leaf, which was further confirmed by soft X-ray scanning transmission microscopy results. Sulfur increased the proportion of Cu (I) species in rice grain, husk and leaf, suggesting the inducing of Cu (II) reduction in rice tissues by S fertilization. These results suggested that fertilization of S in paddy soils increased the accumulation of Cu in rice grain, possibly due to the reduction of Cu (II) to Cu (I) by enhancing glutathione synthesis and increasing the translocation of Cu from shoot to grain. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Biokinetics and biotransformation of DDTs in the marine green mussels Perna viridis.

    PubMed

    Kwong, Raymond W M; Yu, Peter K N; Lam, Paul K S; Wang, Wen-Xiong

    2009-07-26

    The biokinetics of p,p'-dichlorodiphenyltrichloroethane (DDT) and its metabolites, p,p'-dichlorodiphenydichloroethylene (DDE) and p,p'-dichlorodiphenyldichloroethane (DDD), in the green-lipped mussel Perna viridis were characterized in this study. We exposed the mussels to DDT in aqueous or dietary sources and then compared and evaluated the absorption, accumulation, distribution and elimination of DDT and its metabolites (DDD and DDE) in the mussels. In addition, a dynamic model was employed to quantify the depuration kinetics of each DDT compound in various organs of the mussels. The potential biotransformation pathway in the mussels after dietary exposure to DDT was also analyzed. Differing accumulation and elimination patterns of each DDT compound (DDT, DDD and DDE) in various organs were observed. Most of the DDT was confined to the hepatopancreas following either aqueous or dietary exposure, although the biological fate and biokinetics of DDT were differed significantly between routes of exposure. In addition, the elimination of dietary DDT was markedly slower than that following aqueous uptake. The biotransformation of DDT to DDE was rare in the mussels, suggesting that any DDE in the mussels came primarily from the ambient environment instead of through biotransformation process. Nevertheless, DDE may be retained in the mussels because of its exceptionally low elimination rate. In contrast, DDT was biotransformed to DDD in the mussels following dietary uptake, and this biotransformation may facilitate DDT elimination from the mussels.

  3. Perceived employability trajectories: A Swedish cohort study

    PubMed Central

    Törnroos (née Kirves), Kaisa; Bernhard-Oettel, Claudia; Leineweber, Constanze

    2017-01-01

    Objectives: This study identified perceived employability trajectories and their associations with sleeping difficulties and depressive symptoms over time. Methods: The sample was part of the Swedish Longitudinal Survey on Health from 2008 to 2014 (n=4,583). Results: Two stable trajectories (high and low perceived employability over time) and three trajectories with changes (increasing, decreasing, and V-shaped perceived employability over time) were identified. Workers with stable low perceived employability reported more sleeping difficulties and depressive symptoms than those who perceived high or increasing employability. Conclusion: Perceived employability is a rather stable personal resource, which is associated with well-being over time. However, changes in perceived employability do not seem to be echoed in well-being, at least not as immediately as theoretically expected. PMID:28539535

  4. In Silico Prediction of Cytochrome P450-Mediated Biotransformations of Xenobiotics: A Case Study of Epoxidation.

    PubMed

    Zhang, Jing; Ji, Li; Liu, Weiping

    2015-08-17

    Predicting the biotransformation of xenobiotics is important in toxicology; however, as more compounds are synthesized than can be investigated experimentally, powerful computational methods are urgently needed to prescreen potentially useful candidates. Cytochrome P450 enzymes (P450s) are the major enzymes involved in xenobiotic metabolism, and many substances are bioactivated by P450s to form active compounds. An example is the conversion of olefinic substrates to epoxides, which are intermediates in the metabolic activation of many known or suspected carcinogens. We have calculated the activation energies for epoxidation by the active species of P450 enzymes (an iron-oxo porphyrin cation radical oxidant, compound I) for a diverse set of 36 olefinic substrates with state-of-the-art density functional theory (DFT) methods. Activation energies can be estimated by the computationally less demanding method of calculating the ionization potentials of the substrates, which provides a useful and simple predictive model based on the reaction mechanism; however, the preclassification of these diverse substrates into weakly polar and strongly polar groups is a prerequisite for the construction of specific predictive models with good predictability for P450 epoxidation. This approach has been supported by both internal and external validations. Furthermore, the relation between the activation energies for the regioselective epoxidation and hydroxylation reactions of P450s and experimental data has been investigated. The results show that the computational method used in this work, single-point energy calculations with the B3LYP functional including zero-point energy and solvation and dispersion corrections based on B3LYP-optimized geometries, performs well in reproducing the experimental trends of the epoxidation and hydroxylation reactions.

  5. Organoarsenical Biotransformations by Shewanella putrefaciens.

    PubMed

    Chen, Jian; Rosen, Barry P

    2016-08-02

    Microbes play a critical role in the global arsenic biogeocycle. Most studies have focused on redox cycling of inorganic arsenic in bacteria and archaea. The parallel cycles of organoarsenical biotransformations are less well characterized. Here we describe organoarsenical biotransformations in the environmental microbe Shewanella putrefaciens. Under aerobic growth conditions, S. putrefaciens reduced the herbicide MSMA (methylarsenate or MAs(V)) to methylarsenite (MAs(III)). Even though it does not contain an arsI gene, which encodes the ArsI C-As lyase, S. putrefaciens demethylated MAs(III) to As(III). It cleaved the C-As bond in aromatic arsenicals such as the trivalent forms of the antimicrobial agents roxarsone (Rox(III)), nitarsone (Nit(III)) and phenylarsenite (PhAs(III)), which have been used as growth promoters for poultry and swine. S. putrefaciens thiolated methylated arsenicals, converting MAs(V) into the more toxic metabolite monomethyl monothioarsenate (MMMTAs(V)), and transformed dimethylarsenate (DMAs(V)) into dimethylmonothioarsenate (DMMTAs(V)). It also reduced the nitro groups of Nit(V), forming p-aminophenyl arsenate (p-arsanilic acid or p-AsA(V)), and Rox(III), forming 3-amino-4-hydroxybenzylarsonate (3A4HBzAs(V)). Elucidation of organoarsenical biotransformations by S. putrefaciens provides a holistic appreciation of how these environmental pollutants are degraded.

  6. Development of the isolated perfused porcine skin flap for in vitro studies of percutaneous absorption pharmacokinetics and cutaneous biotransformation

    SciTech Connect

    Carver, M.P.

    1988-01-01

    The isolated perfused porcine skin flap (IPPSF) has proven to be a valuable in vitro tool for studying the physiology and biochemistry of skin and for identifying biochemical and histological markers of direct cutaneous toxicity. The present experiments were undertaken for two purposes: (1) to develop a pharmacokinetic model, based on dermal penetration in the IPPSF, which is predictive of percutaneous absorption in vivo, and (2) to examine cutaneous biotransformation of the important agricultural poison parathion (P). Dosing solutions of {sup 14}C-radiolabelled compounds representing 3 chemical classes-organic acid/base (benzoic acid (B), caffeine (C)), organophosphate (OP) pesticides, and steroid hormones, were applied topically in ethanol at 40 {mu}m cm{sup {minus}2}, both in vivo and on the IPPSF. A 3-compartment pharmacokinetic model describing mass transfer from the surface (C{sub 1}), diffusion through epidermis and dermis (C{sub 2}), and transfer into the perfusate (C{sub 3}), was developed based on flux through the IPPSF from 0-8 hr. Model simulations were predictive of percutaneous absorption in vivo for the OP's and steroids. Modification of the basic 3-compartment model to account for fast and slow tissue-release processes (B) and for flux-dependent perfusage flow increases (C), provided excellent in vivo-in vitro correlation over all 7 compounds.

  7. In vitro study on the biotransformation and cytotoxicity of three hexabromocyclododecane diastereoisomers in liver cells.

    PubMed

    Huang, Xiaomei; Chen, Cen; Shang, Yu; Zhong, Yufang; Ren, Guofa; Yu, Zhiqiang; An, Jing

    2016-10-01

    In order to clarify the cytotoxicity of hexabromocyclododecane (HBCD) diastereoisomers, and to investigate the correlation of cytotoxicity and biotransformation of HBCDs, the immortalized human liver cells L02 and human hepatoma cells HepG2 were exposed to individual HBCD diastereoisomer (α-, β- and γ-HBCD). Cytotoxicity was assayed in terms of cell viability, reactive oxygen species (ROS) level and DNA damage. Metabolic rate, bioisomerization and enantiomer fractions were analyzed using the liquid chromatograph coupled to triple quadrupole mass spectrometer (LC-MS/MS). The α-, β- and γ-HBCD all had cytotoxicity in L02 and HepG2 cells with the toxicity order β-HBCD ≥ γ-HBCD > α-HBCD according to the results of proliferation assay. The cytotoxicity mechanism between the two cells seemed different: a) the stability of intracellular redox state plays an important role in inducing cell toxicity in HepG2 cells. b) DNA damage status is central to inhibit proliferation in L02 cells. The metabolic capability of HepG2 was superior to L02 for HBCD diastereoisomers, which may explain the greater toxicity of HBCDs in HepG2 cells. The bioisomerization and enantiomer enrichment were also detected in this study, although the results were inconsistent with other reports, which might result from species-specific differences in HBCDs metabolism or experimental conditions. The cytotoxicity and metabolic mechanism of individual enantiomers must be further investigated to evaluate the health risks of HBCDs.

  8. Earth Abides Arsenic Biotransformations.

    PubMed

    Zhu, Yong-Guan; Yoshinaga, Masafumi; Zhao, Fang-Jie; Rosen, Barry P

    2014-05-01

    Arsenic is the most prevalent environmental toxic element and causes health problems throughout the world. The toxicity, mobility, and fate of arsenic in the environment are largely determined by its speciation, and arsenic speciation changes are driven, at least to some extent, by biological processes. In this article, biotransformation of arsenic is reviewed from the perspective of the formation of Earth and the evolution of life, and the connection between arsenic geochemistry and biology is described. The article provides a comprehensive overview of molecular mechanisms of arsenic redox and methylation cycles as well as other arsenic biotransformations. It also discusses the implications of arsenic biotransformation in environmental remediation and food safety, with particular emphasis on groundwater arsenic contamination and arsenic accumulation in rice.

  9. Earth Abides Arsenic Biotransformations

    PubMed Central

    Zhu, Yong-Guan; Yoshinaga, Masafumi; Zhao, Fang-Jie; Rosen, Barry P.

    2015-01-01

    Arsenic is the most prevalent environmental toxic element and causes health problems throughout the world. The toxicity, mobility, and fate of arsenic in the environment are largely determined by its speciation, and arsenic speciation changes are driven, at least to some extent, by biological processes. In this article, biotransformation of arsenic is reviewed from the perspective of the formation of Earth and the evolution of life, and the connection between arsenic geochemistry and biology is described. The article provides a comprehensive overview of molecular mechanisms of arsenic redox and methylation cycles as well as other arsenic biotransformations. It also discusses the implications of arsenic biotransformation in environmental remediation and food safety, with particular emphasis on groundwater arsenic contamination and arsenic accumulation in rice. PMID:26778863

  10. Earth Abides Arsenic Biotransformations

    NASA Astrophysics Data System (ADS)

    Zhu, Yong-Guan; Yoshinaga, Masafumi; Zhao, Fang-Jie; Rosen, Barry P.

    2014-05-01

    Arsenic is the most prevalent environmental toxic element and causes health problems throughout the world. The toxicity, mobility, and fate of arsenic in the environment are largely determined by its speciation, and arsenic speciation changes are driven, at least to some extent, by biological processes. In this article, biotransformation of arsenic is reviewed from the perspective of the formation of Earth and the evolution of life, and the connection between arsenic geochemistry and biology is described. The article provides a comprehensive overview of molecular mechanisms of arsenic redox and methylation cycles as well as other arsenic biotransformations. It also discusses the implications of arsenic biotransformation in environmental remediation and food safety, with particular emphasis on groundwater arsenic contamination and arsenic accumulation in rice.

  11. Microbial biotransformation of bioactive flavonoids.

    PubMed

    Cao, Hui; Chen, Xiaoqing; Jassbi, Amir Reza; Xiao, Jianbo

    2015-01-01

    The bioactive flavonoids are considered as the most important phytochemicals in food, which exert a wide range of biological benefits for human being. Microbial biotransformation strategies for production of flavonoids have attracted considerable interest because they allow yielding novel flavonoids, which do not exist in nature. In this review, we summarize the existing knowledge on the production and biotransformation of flavonoids by various microbes. The main reactions during microbial biotransformation are hydroxylation, dehydroxylation, O-methylation, O-demethylation, glycosylation, deglycosylation, dehydrogenation, hydrogenation, C ring cleavage of the benzo-γ-pyrone system, cyclization, and carbonyl reduction. Cunninghamella, Penicillium, and Aspergillus strains are very popular to biotransform flavonoids and they can perform almost all the reactions with excellent yields. Aspergillus niger is one of the most applied microorganisms in the flavonoids' biotransformation; for example, A. niger can transfer flavanone to flavan-4-ol, 2'-hydroxydihydrochalcone, flavone, 3-hydroxyflavone, 6-hydroxyflavanone, and 4'-hydroxyflavanone. The hydroxylation of flavones by microbes usually happens on the ortho position of hydroxyl group on the A ring and C-4' position of the B ring and microbes commonly hydroxylate flavonols at the C-8 position. The microorganisms tend to hydroxylate flavanones at the C-5, 6, and 4' positions; however, for prenylated flavanones, dihydroxylation often takes place on the C4α=C5α double bond on the prenyl group (the side chain of A ring). Isoflavones are usually hydroxylated at the C-3' position of the B ring by microorganisms. The microbes convert flavonoids to their 7-O-glycosides and 3-O-glycosides (when flavonoids have a hydroxyl moiety at the C-3 position). The demethylation of multimethoxyl flavonoids by microbes tends to happen at the C-3' and C-4' positions of the B ring. Multimethoxyl flavanones and isoflavone are demethylated at

  12. Domestic violence and employment: a qualitative study.

    PubMed

    Swanberg, Jennifer E; Logan, T K

    2005-01-01

    This exploratory study sought to gather detailed information about how domestic violence affects women's employment, specifically to identify the types of job interference tactics used by abusers and their consequences on women's job performance; identify and understand the context associated with disclosure about victimization to employers and coworkers; and identify the supports offered to employees after disclosure. Qualitative analyses, guided by grounded theory, revealed that perpetrators exhibited job interference behaviors before, during, and after work. Abuser tactics reduced women's job performance as measured by absenteeism, tardiness, job leavings, and terminations. Among women who disclosed victimization to employers, informal and formal job supports were offered. Workplace supports led to short-term job retention, but fear and safety issues mitigated employers' attempts to retain workers. ((c) 2005 APA, all rights reserved).

  13. Building Employer Capacity to Support Meaningful Employment for Persons with Developmental Disabilities: A Grounded Theory Study of Employment Support Perspectives.

    PubMed

    Rashid, Marghalara; Hodgetts, Sandra; Nicholas, David

    2017-08-29

    To explore strategies to build employer capacity to support people with DD in meaningful employment from perspective of employment support workers. A grounded theory study was conducted with 34 employment support individuals. A theoretical sampling approach was used to identify and recruit participants from multiple sites in Ontario and Alberta. Three main themes, with seven sub-themes, emerged: (1) experiences of supporting employment finding for people with DD, (2) institutional influences on employee experiences, and (3) attitudes, assumptions and stigma. Several recommendations related to building employer capacity were offered. Our findings provide insight on specific elements and strategies that can support building employer capacity for persons with DD.

  14. Walworth County Employer Needs Assessment Study.

    ERIC Educational Resources Information Center

    Stoehr, Keith W.; Banerdt, Jack

    In 1982, a study was conducted to obtain information from businesses, industries, and agencies in Walworth County that would assist Gateway Technical Institute (GTI) in providing programs and services to meet employers' manpower needs. Surveys were administered to 133 businesses and industries, requesting information on the firms' characteristics,…

  15. New method for the study of Amaryllidaceae alkaloid biosynthesis using biotransformation of deuterium-labeled precursor in tissue cultures.

    PubMed

    El Tahchy, Anna; Boisbrun, Michel; Ptak, Agata; Dupire, François; Chrétien, Françoise; Henry, Max; Chapleur, Yves; Laurain-Mattar, Dominique

    2010-01-01

    Biotransformation of deuterated-4'-O-methylnorbelladine into alkaloids galanthamine and lycorine in tissue cultures of Leucojum aestivum was demonstrated using HPLC coupled to mass spectrometry. GC-MS screening was also carried to investigate other native and deuterated alkaloids. A total of six labeled alkaloids were identified indicating that 4'-O-methyl-d(3)-norbelladine is incorporated into three different groups of Amaryllidaceae alkaloids that are biosynthesized by three modes of intramolecular oxidative phenol coupling.

  16. Molecular modeling and simulation studies of recombinant laccase from Yersinia enterocolitica suggests significant role in the biotransformation of non-steroidal anti-inflammatory drugs

    SciTech Connect

    Singh, Deepti; Rawat, Surender; Waseem, Mohd; Gupta, Sunita; Lynn, Andrew; Nitin, Mukesh; Ramchiary, Nirala; Sharma, Krishna Kant

    2016-01-08

    The YacK gene from Yersinia enterocolitica strain 7, cloned in pET28a vector and expressed in Escherichia coli BL21 (DE3), showed laccase activity when oxidized with 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) and guaiacol. The recombinant laccase protein was purified and characterized biochemically with a molecular mass of ≈58 KDa on SDS-PAGE and showed positive zymogram with ABTS. The protein was highly robust with optimum pH 9.0 and stable at 70 °C upto 12 h with residual activity of 70%. Kinetic constants, K{sub m} values, for ABTS and guaiacol were 675 μM and 2070 μM, respectively, with corresponding Vmax values of 0.125 μmol/ml/min and 6500 μmol/ml/min. It also possess antioxidative property against BSA and Cu{sup 2+}/H{sub 2}O{sub 2} model system. Constant pH MD simulation studies at different protonation states of the system showed ABTS to be most stable at acidic pH, whereas, diclofenac at neutral pH. Interestingly, aspirin drifted out of the binding pocket at acidic and neutral pH, but showed stable binding at alkaline pH. The biotransformation of diclofenac and aspirin by laccase also corroborated the in silico results. This is the first report on biotransformation of non-steroidal anti-inflammatory drugs (NSAIDs) using recombinant laccase from gut bacteria, supported by in silico simulation studies. - Highlights: • Laccase from Yersinia enterocolitica strain 7 was expressed in Escherichia coli BL21 (DE3). • Recombinant laccase was found to be thermostable and alkali tolerant. • The in silico and experimental studied proves the biotransformation of NSAIDs. • Laccase binds to ligands differentially under different protonation state. • Laccase also possesses free radical scavenging property.

  17. Ligand-binding mass spectrometry to study biotransformation of fusion protein drugs and guide immunoassay development: strategic approach and application to peptibodies targeting the thrombopoietin receptor.

    PubMed

    Hall, Michael P; Gegg, Colin; Walker, Kenneth; Spahr, Christopher; Ortiz, Robert; Patel, Vimal; Yu, Steven; Zhang, Liana; Lu, Hsieng; DeSilva, Binodh; Lee, Jean W

    2010-12-01

    The knowledge of in vivo biotransformation (e.g., proteolysis) of protein therapeutic candidates reveals structural liabilities that impact stability. This information aids the development and confirmation of ligand-binding assays with the required specificity for bioactive moieties (including intact molecule and metabolites) for appropriate PK profiling. Furthermore, the information can be used for re-engineering of constructs to remove in vivo liabilities in order to design the most stable candidates. We have developed a strategic approach of ligand-binding mass spectrometry (LBMS) to study biotransformation of fusion proteins of peptides fused to human Fc ("peptibodies") using anti-human Fc immunoaffinity capture followed by tiered mass spectrometric interrogation. LBMS offers the combined power of selectivity of ligand capture with the specificity and detailed molecular-level information of mass spectrometry. In this paper, we demonstrate the preclinical application of LBMS to three peptibodies, AMG531 (romiplostim), AMG195(linear), and AMG195(loop), that target the thrombopoietin receptor. The data show that ligand capture offers excellent sample cleanup and concentration of intact peptibodies and metabolites for subsequent query by matrix-assisted laser desorption ionization time-of-flight mass spectrometry for identification of in vivo proteolytic points. Additional higher-resolution analysis by nanoscale liquid chromatography interfaced with electrospray ionization mass spectrometry is required for identification of heterogeneous metabolites. Five proteolytic points are accurately identified for AMG531 and two for AMG195(linear), while AMG195(loop) is the most stable construct in rats. We recommend the use of LBMS to assess biotransformation and in vivo stability during early preclinical phase development for all novel fusion proteins.

  18. Biotransformation of volatile fatty acids to polyhydroxyalkanoates by employing mixed microbial consortia: The effect of pH and carbon source.

    PubMed

    Kourmentza, C; Kornaros, M

    2016-12-01

    Mixed microbial cultures that undergo successful enrichment, following eco-biotechnological approaches, to form a community dominant in polyhydroxyalkanoates (PHA) forming bacteria, represent an attractive economic alternative towards the production of those biopolymers. In the present study, an enriched mixed culture was investigated for the production of PHA at different initial pH values under non-controlled conditions in order to minimize process control and operational costs. Short-chain fatty acids were provided as PHA precursors and they were tested as sole carbon sources and as mixtures under nitrogen deficiency. By the obtained kinetic and stoichiometric parameters it was shown that at an initial pH value of 6.90 PHA production was favored. Butyrate was characterized as the preferred carbon source, whereas simultaneous feeding led to increased rates and yields when butyrate and acetate were present. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Phthalate biotransformation by rainbow trout

    SciTech Connect

    Barron, M.G.; Hayton, W.L.

    1994-12-31

    The biotransformation of di(2-ethylhexyl)phthalate (DEHP) was studied in rainbow trout because DEHP bioconcentration is limited by metabolism. Biological fluids were collected following intravascular administration. Methylesterified metabolites were identified using rodent-derived standards and nonlinear gradient elution HPLC; metabolites were confirmed by gas chromatography. Similarities between the biotransformation of DEHP by rainbow trout and mammalian species included: (1) mono-2-ethylhexyl phthalate (MEHP) appeared to be the obligatory first step in DEHP metabolism; (2) the phthalate ring was not oxidized; (3) phthalic acid was a minor metabolite; and (4) several metabolites contained multiple oxidations of the 2-ethylhexyl moiety of MEHP. No metabolites unique to rainbow trout were identified. However, fewer oxidized metabolites were identified in rainbow trout than in mammalian species, possibly due to limited mitochondrial metabolism of MEHP in rainbow trout. The amount of biliary MEHP glucuronide after intravascular administration of DEHP was substantially less than reported in rainbow trout exposed to DEHP via the water. The results confirmed that DEHP metabolism in rainbow trout proceeds by initial rapid formation of MEHP, followed by excretion or extensive oxidation by microsomal P450.

  20. A quantitative study of the biotransformation of insulin-enhancing VO(2+) compounds.

    PubMed

    Sanna, Daniele; Buglyó, Péter; Micera, Giovanni; Garribba, Eugenio

    2010-08-01

    Potentiometric (pH titrations) and spectroscopic (electron paramagnetic resonance) methods have been used to determine the thermodynamic stability constants of the various VO(2+) complexes formed after the interaction of four insulin-enhancing vanadium compounds, [VO(6-mepic)(2)], cis-[VO(pic)(2)(H(2)O)], [VO(acac)(2)], and [VO(dhp)(2)], where 6-mepic, pic, acac, and dhp indicate the deprotonated forms of 6-methylpicolinic acid, picolinic acid, acetylacetone, and 1,2-dimethyl-3-hydroxy-4(1H)-pyridinone, with high molecular mass [human serum apotransferrin (hTf) and human serum albumin (HSA)] and low molecular mass (lactate) components of blood serum. In particular, log beta values for the formation of (VO)hTf (13.0 +/- 0.5), (VO)(2)hTf (25.5 +/- 0.5), (VO)HSA (9.1 +/- 1.0), (VO) (2) (d) HSA (20.9 +/- 1.0), cis-VO(dhp)(2)(hTf) (25.5 +/- 0.6), cis-VO(dhp)(2)(HSA) (25.9 +/- 0.6), (VO)hTf(lact) (14.5 +/- 0.8), (VO)(2)hTf(lact)(2) (28.5 +/- 0.8), (VO)hTf(pic) (15.6 +/- 0.8), and (VO)(2)hTf(pic)(2) (30.4 +/- 0.8) were determined. The values of the stability constants were used to compare the calculated composition of ternary and quinary systems with that recently proposed by some of us through electron paramagnetic resonance and density functional theory methods (Sanna et al. in Inorg. Chem. 49:174-187, 2010) and to predict the distribution of VO(2+) ion in blood serum when one of the four insulin-enhancing vanadium compounds studied, [VO(carrier)(2)], is administered.

  1. Sublethal toxicity and biotransformation of pyrene in Lumbriculus variegatus (Oligochaeta).

    PubMed

    Mäenpää, K; Leppänen, M T; Kukkonen, J V K

    2009-04-01

    The aim of this work was to study the toxicity and biotransformation of polyaromatic hydrocarbon (PAH) pyrene in the oligochaete aquatic worm, Lumbriculus variegatus. PAHs are ubiquitous environmental pollutants that pose a hazard to aquatic organisms, and metabolizing capability is poorly known in the case of many invertebrate species. To study the toxicity and biotransformation of pyrene, the worm was exposed for 15 days to various concentrations of water-borne pyrene. The dorsal blood vessel pulse rate was used as a sublethal endpoint. Pyrene biotransformation by L. variegatus was studied and the critical body residues (CBR) were estimated for pyrene toxicity. The toxicokinetics of pyrene uptake was evaluated. A combination of radiolabeled (14C) and nonlabeled pyrene was used in the exposures, and liquid scintillation counting (LSC) and high-pressure liquid chromatography were employed in both water and tissue residue analyses. The results showed that L. variegatus was moderately able to metabolize pyrene to 1-hydroxypyrene (1-HP), thus demonstrating that the phase-I-like oxidizing enzyme system metabolizes pyrene in L. variegatus. The amount of the 1-HP was 1-2% of the amount of pyrene in the worm tissues. The exposure to pyrene reduced the blood vessel pulse rate significantly (p<0.05), showing that pyrene had a narcotic effect. The estimated CBRs remained constant during the exposure time, varying from 0.120 to 0.174 mmol pyrene/kg worm wet weight. The bioconcentration factors (BCF) decreased as exposure concentration increased. It was suggested that the increased toxicity of pyrene accounted for the decrease in BCFs by lowering the activity of the organism.

  2. Biotransformations of antidiabetic vanadium prodrugs in mammalian cells and cell culture media: A XANES spectroscopic study

    DOE PAGES

    Levina, Aviva; McLeod, Andrew I.; Pulte, Anna; ...

    2015-04-23

    The antidiabetic activities of vanadium(V) and -(IV) prodrugs are determined by their ability to release active species upon interactions with components of biological media. The first X-ray absorption spectroscopic study of the reactivity of typical vanadium (V) antidiabetics, vanadate ([VVO4]3–, A) and a vanadium(IV) bis(maltolato) complex (B), with mammalian cell cultures has been performed using HepG2 (human hepatoma), A549 (human lung carcinoma), and 3T3-L1 (mouse adipocytes and preadipocytes) cell lines, as well as the corresponding cell culture media. X-ray absorption near-edge structure data were analyzed using empirical correlations with a library of model vanadium(V), -(IV), and -(III) complexes. Both Amore » and B ([V] = 1.0 mM) gradually converged into similar mixtures of predominantly five- and six-coordinate VV species (~75% total V) in a cell culture medium within 24 h at 310 K. Speciation of V in intact HepG2 cells also changed with the incubation time (from ~20% to ~70% VIV of total V), but it was largely independent of the prodrug used (A or B) or of the predominant V oxidation state in the medium. Subcellular fractionation of A549 cells suggested that VV reduction to VIV occurred predominantly in the cytoplasm, while accumulation of VV in the nucleus was likely to have been facilitated by noncovalent bonding to histone proteins. The nuclear VV is likely to modulate the transcription process and to be ultimately related to cell death at high concentrations of V, which may be important in anticancer activities. Mature 3T3-L1 adipocytes (unlike for preadipocytes) showed a higher propensity to form VIV species, despite the prevalence of VV in the medium. Lastly, the distinct V biochemistry in these cells is consistent with their crucial role in insulin-dependent glucose and fat metabolism and may also point to an endogenous role of V in adipocytes.« less

  3. Biotransformations of antidiabetic vanadium prodrugs in mammalian cells and cell culture media: A XANES spectroscopic study

    SciTech Connect

    Levina, Aviva; McLeod, Andrew I.; Pulte, Anna; Aitken, Jade B.; Lay, Peter A.

    2015-04-23

    The antidiabetic activities of vanadium(V) and -(IV) prodrugs are determined by their ability to release active species upon interactions with components of biological media. The first X-ray absorption spectroscopic study of the reactivity of typical vanadium (V) antidiabetics, vanadate ([VVO4]3–, A) and a vanadium(IV) bis(maltolato) complex (B), with mammalian cell cultures has been performed using HepG2 (human hepatoma), A549 (human lung carcinoma), and 3T3-L1 (mouse adipocytes and preadipocytes) cell lines, as well as the corresponding cell culture media. X-ray absorption near-edge structure data were analyzed using empirical correlations with a library of model vanadium(V), -(IV), and -(III) complexes. Both A and B ([V] = 1.0 mM) gradually converged into similar mixtures of predominantly five- and six-coordinate VV species (~75% total V) in a cell culture medium within 24 h at 310 K. Speciation of V in intact HepG2 cells also changed with the incubation time (from ~20% to ~70% VIV of total V), but it was largely independent of the prodrug used (A or B) or of the predominant V oxidation state in the medium. Subcellular fractionation of A549 cells suggested that VV reduction to VIV occurred predominantly in the cytoplasm, while accumulation of VV in the nucleus was likely to have been facilitated by noncovalent bonding to histone proteins. The nuclear VV is likely to modulate the transcription process and to be ultimately related to cell death at high concentrations of V, which may be important in anticancer activities. Mature 3T3-L1 adipocytes (unlike for preadipocytes) showed a higher propensity to form VIV species, despite the prevalence of VV in the medium. Lastly, the distinct V biochemistry in these cells is consistent with their crucial role in insulin-dependent glucose and fat metabolism and may also point to an endogenous role of V in

  4. Biotransformations of Antidiabetic Vanadium Prodrugs in Mammalian Cells and Cell Culture Media: A XANES Spectroscopic Study.

    PubMed

    Levina, Aviva; McLeod, Andrew I; Pulte, Anna; Aitken, Jade B; Lay, Peter A

    2015-07-20

    The antidiabetic activities of vanadium(V) and -(IV) prodrugs are determined by their ability to release active species upon interactions with components of biological media. The first X-ray absorption spectroscopic study of the reactivity of typical vanadium (V) antidiabetics, vanadate ([V(V)O4](3-), A) and a vanadium(IV) bis(maltolato) complex (B), with mammalian cell cultures has been performed using HepG2 (human hepatoma), A549 (human lung carcinoma), and 3T3-L1 (mouse adipocytes and preadipocytes) cell lines, as well as the corresponding cell culture media. X-ray absorption near-edge structure data were analyzed using empirical correlations with a library of model vanadium(V), -(IV), and -(III) complexes. Both A and B ([V] = 1.0 mM) gradually converged into similar mixtures of predominantly five- and six-coordinate V(V) species (∼75% total V) in a cell culture medium within 24 h at 310 K. Speciation of V in intact HepG2 cells also changed with the incubation time (from ∼20% to ∼70% V(IV) of total V), but it was largely independent of the prodrug used (A or B) or of the predominant V oxidation state in the medium. Subcellular fractionation of A549 cells suggested that V(V) reduction to V(IV) occurred predominantly in the cytoplasm, while accumulation of V(V) in the nucleus was likely to have been facilitated by noncovalent bonding to histone proteins. The nuclear V(V) is likely to modulate the transcription process and to be ultimately related to cell death at high concentrations of V, which may be important in anticancer activities. Mature 3T3-L1 adipocytes (unlike for preadipocytes) showed a higher propensity to form V(IV) species, despite the prevalence of V(V) in the medium. The distinct V biochemistry in these cells is consistent with their crucial role in insulin-dependent glucose and fat metabolism and may also point to an endogenous role of V in adipocytes.

  5. Biotransformations of Antidiabetic Vanadium Prodrugs in Mammalian Cells and Cell Culture Media: A XANES Spectroscopic Study

    PubMed Central

    2016-01-01

    The antidiabetic activities of vanadium(V) and -(IV) prodrugs are determined by their ability to release active species upon interactions with components of biological media. The first X-ray absorption spectroscopic study of the reactivity of typical vanadium (V) antidiabetics, vanadate ([VVO4]3–, A) and a vanadium(IV) bis(maltolato) complex (B), with mammalian cell cultures has been performed using HepG2 (human hepatoma), A549 (human lung carcinoma), and 3T3-L1 (mouse adipocytes and preadipocytes) cell lines, as well as the corresponding cell culture media. X-ray absorption near-edge structure data were analyzed using empirical correlations with a library of model vanadium(V), -(IV), and -(III) complexes. Both A and B ([V] = 1.0 mM) gradually converged into similar mixtures of predominantly five- and six-coordinate VV species (∼75% total V) in a cell culture medium within 24 h at 310 K. Speciation of V in intact HepG2 cells also changed with the incubation time (from ∼20% to ∼70% VIV of total V), but it was largely independent of the prodrug used (A or B) or of the predominant V oxidation state in the medium. Subcellular fractionation of A549 cells suggested that VV reduction to VIV occurred predominantly in the cytoplasm, while accumulation of VV in the nucleus was likely to have been facilitated by noncovalent bonding to histone proteins. The nuclear VV is likely to modulate the transcription process and to be ultimately related to cell death at high concentrations of V, which may be important in anticancer activities. Mature 3T3-L1 adipocytes (unlike for preadipocytes) showed a higher propensity to form VIV species, despite the prevalence of VV in the medium. The distinct V biochemistry in these cells is consistent with their crucial role in insulin-dependent glucose and fat metabolism and may also point to an endogenous role of V in adipocytes. PMID:25906315

  6. Study of the Biotransformation of Tongmai Formula by Human Intestinal Flora and Its Intestinal Permeability across the Caco-2 Cell Monolayer.

    PubMed

    Wu, Shuai; Xu, Wei; Wang, Fu-Rong; Yang, Xiu-Wei

    2015-10-15

    Tongmai formula (TMF) is a well-known Chinese medicinal preparation that contains isoflavones as its major bioactive constituents. As traditional Chinese medicines (TCMs) are usually used by oral administration, their fate inside the intestinal lumen, including their biotransformation by human intestinal flora (HIF) and intestinal absorption deserves study. In this work TMF extract was incubated with human intestinal bacteria under anaerobic conditions and the changes in the twelve main constituents of TMF were then investigated. Their intestinal permeabilities, i.e., the transport capability across the intestinal brush border were investigated with a human colon carcinoma cell line (Caco-2) cell monolayer model to predict the absorption mechanism. Meanwhile, rapid HPLC-DAD methods were established for the assay. According to the biotransformation curves of the twelve constituents and the permeability coefficients, the intestinal absorption capacity of the typical compounds was elevated from the levels of 10(-7) cm/s to 10(-5) cm/s from those of the original compounds in TMF. Among them the main isoflavone glycosides puerarin (4), mirificin (6) and daidzin (7) were transformed into the same aglycone, daidzein (10). Therefore it was predicted that the aglycone compounds might be the real active ingredients in TMF. The models used can represent a novel path for the TCM studies.

  7. Microbial toxicity and characterization of DNAN (bio)transformation product mixtures.

    PubMed

    Olivares, Christopher I; Sierra-Alvarez, Reyes; Alvarez-Nieto, Cristina; Abrell, Leif; Chorover, Jon; Field, Jim A

    2016-07-01

    2,4-Dinitroanisole (DNAN) is an emerging insensitive munitions compound. It undergoes rapid (bio)transformation in soils and anaerobic sludge. The primary transformation pathway catalyzed by a combination of biotic and abiotic factors is nitrogroup reduction followed by coupling of reactive intermediates to form azo-dimers. Additional pathways include N-acetylation and O-demethoxylation. Toxicity due to (bio)transformation products of DNAN has received little attention. In this study, the toxicity of DNAN (bio)transformation monomer products and azo-dimer and trimer surrogates to acetoclastic methanogens and the marine bioluminescent bacterium, Allivibrio fischeri, were evaluated. Methanogens were severely inhibited by 3-nitro-4-methoxyaniline (MENA), with a 50%-inhibiting concentration (IC50) of 25 μM, which is more toxic than DNAN with the same assay, but posed a lower toxicity to Allivibrio fischeri (IC50 = 219 μM). On the other hand, N-(5-amino-2-methoxyphenyl) acetamide (Ac-DAAN) was the least inhibitory test-compound for both microbial targets. Azo-dimer and trimer surrogates were very highly toxic to both microbial systems, with a toxicity similar or stronger than that of DNAN. A semi-quantitative LC-QTOF-MS method was employed to determine product mixture profiles at different stages of biotransformation, and compared with the microbial toxicity of the product-mixtures formed. Methanogenic toxicity increased due to putative reactive nitroso-intermediates as DNAN was reduced. However, the inhibition later attenuated as dimers became the predominant products in the mixtures. In contrast, A. fischeri tolerated the initial biotransformation products but were highly inhibited by the predominant azo-dimer products formed at longer incubation times, suggesting these ultimate products are more toxic than DNAN. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Biotransformation of pharmaceuticals under nitrification, nitratation and heterotrophic conditions.

    PubMed

    Fernandez-Fontaina, E; Gomes, I B; Aga, D S; Omil, F; Lema, J M; Carballa, M

    2016-01-15

    The effect of nitrification, nitratation and heterotrophic conditions on the biotransformation of several pharmaceuticals in a highly enriched nitrifying activated sludge was evaluated in this study by selective activation of ammonia oxidizing bacteria (AOB), nitrite oxidizing bacteria (NOB) and heterotrophic bacteria. Nitrifiers displayed a noticeable capacity to process ibuprofen due to hydroxylation by ammonia monooxygenase (AMO) to produce 2-hydroxy-ibuprofen. Naproxen was also biotransformed under nitrifying conditions. On the other hand, heterotrophic bacteria present in the nitrifying activated sludge (NAS) biotransformed sulfamethoxazole. In contrast, both nitrifying and heterotrophic activities were ineffective against diclofenac, diazepam, carbamazepine and trimethoprim. Similar biotransformation rates of erythromycin, roxithromycin and fluoxetine were observed under all conditions tested. Overall, results from this study give more evidence on the role of the different microbial communities present in activated sludge reactors on the biological removal of pharmaceuticals. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. In Vivo Biotransformation Rates of Organic Chemicals in Fish: Relationship with Bioconcentration and Biomagnification Factors.

    PubMed

    Lo, Justin C; Letinski, Daniel J; Parkerton, Thomas F; Campbell, Dave A; Gobas, Frank A P C

    2016-12-20

    In vivo dietary bioaccumulation experiments for 85 hydrophobic organic substances were conducted to derive the in vivo gastrointestinal biotransformation rates, somatic biotransformation rates, bioconcentration factors (BCF), and biomagnification factors (BMF) for improving methods for bioaccumulation assessment and to develop an in vivo biotransformation rate database for QSAR development and in vitro to in vivo biotransformation rate extrapolation. The capacity of chemicals to be biotransformed in fish was found to be highly dependent on the route of exposure. Somatic biotransformation was the dominant pathway for most chemicals absorbed via the respiratory route. Intestinal biotransformation was the dominant metabolic pathway for most chemicals absorbed via the diet. For substances not biotransformed or transformed exclusively in the body of the fish, the BCF and BMF appeared to be closely correlated. For substances subject to intestinal biotransformation, the same correlation did not apply. We conclude that intestinal biotransformation and bioavailability in water can modulate the relationship between the BCF and BMF. This study also supports a fairly simple rule of thumb that may be useful in the interpretation of dietary bioaccumulation tests; i.e., chemicals with a BMFL of <1 tend to exhibit BCFs based on either the freely dissolved (BCFWW,fd) or the total concentration (BCFWW,t) of the chemical in the water that is less than 5000.

  10. Molecular modeling and simulation studies of recombinant laccase from Yersinia enterocolitica suggests significant role in the biotransformation of non-steroidal anti-inflammatory drugs.

    PubMed

    Singh, Deepti; Rawat, Surender; Waseem, Mohd; Gupta, Sunita; Lynn, Andrew; Nitin, Mukesh; Ramchiary, Nirala; Sharma, Krishna Kant

    2016-01-08

    The YacK gene from Yersinia enterocolitica strain 7, cloned in pET28a vector and expressed in Escherichia coli BL21 (DE3), showed laccase activity when oxidized with 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) and guaiacol. The recombinant laccase protein was purified and characterized biochemically with a molecular mass of ≈58 KDa on SDS-PAGE and showed positive zymogram with ABTS. The protein was highly robust with optimum pH 9.0 and stable at 70 °C upto 12 h with residual activity of 70%. Kinetic constants, Km values, for ABTS and guaiacol were 675 μM and 2070 μM, respectively, with corresponding Vmax values of 0.125 μmol/ml/min and 6500 μmol/ml/min. It also possess antioxidative property against BSA and Cu(2+)/H2O2 model system. Constant pH MD simulation studies at different protonation states of the system showed ABTS to be most stable at acidic pH, whereas, diclofenac at neutral pH. Interestingly, aspirin drifted out of the binding pocket at acidic and neutral pH, but showed stable binding at alkaline pH. The biotransformation of diclofenac and aspirin by laccase also corroborated the in silico results. This is the first report on biotransformation of non-steroidal anti-inflammatory drugs (NSAIDs) using recombinant laccase from gut bacteria, supported by in silico simulation studies. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Biotransformation of α- and β-pinene into flavor compounds.

    PubMed

    Vespermann, Kele A C; Paulino, Bruno N; Barcelos, Mayara C S; Pessôa, Marina G; Pastore, Glaucia M; Molina, Gustavo

    2017-03-01

    Products that bear the label "natural" have gained more attention in the marketplace. In this approach, the production of aroma compounds through biotransformation or bioconversion has been receiving more incentives in economic and research fields. Among the substrates used in these processes, terpenes can be highlighted for their versatility and low cost; some examples are limonene, α-pinene, and β-pinene. This work focused on the biotransformation of the two bicyclic monoterpenes, α-pinene and β-pinene; the use of different biocatalysts; the products obtained; and the conditions employed in the process.

  12. Recovery of pyruvic acid from biotransformation solutions.

    PubMed

    Ma, C Q; Li, J C; Qiu, J H; Wang, M; Xu, P

    2006-04-01

    The aim of this investigation was to separate pyruvic acid of biotransformation solutions from lactic acid through complex extraction. For this purpose, complex extraction was investigated from model solutions. Tri-n-octanylamine (TOA) was used as the extractant. The effects of various diluents, the stoichiometry of pyruvic acid to TOA, and the initial pH of the aqueous phase on the extraction process were investigated in this study. The effects of sodium hydroxide (NaOH) and trimethylamine (TMA) on the back extraction process were also studied, respectively. The optimal conditions attained from the model solutions proved efficient on the biotransformation solutions of different concentrations. A total recovery of 71-82% of pyruvic acid was obtained, whereas 89-92% of lactic acid was removed. The purity of pyruvic acid reached 97% after the removal of TMA by a simple distillation.

  13. Biotransformation of the pesticide sodium arsenate.

    PubMed

    Shariatpanahi, M; Anderson, A C; Abdelghani, A A; Englande, A J; Hughes, J; Wilkinson, R F

    1981-01-01

    Biotransformation is an important parameter in assessing the environmental impact and fate of pesticides since metabolites produced may be either more or less toxic than the parent compound. Sodium arsenate (+5 inorganic), the wood preservative and insecticide, may be converted to both inorganic (+3) and organic compounds (-3) by microorganisms in soil, sediment and water bodies. Biotransformation of sodium arsenate was studied in pure cultures of 5 bacterial species using a mineral salt and limited carbon source medium. Arsenate concentrations were 10 microgram/ml and 100 microgram/ml of arsenic respectively. The rate of biodegradation of the parent compound was described by a first order composite exponential equation of the form Ct = C1e-k1t+C2e-k2t. Rates of production of metabolites (arsenite, monomethylarsine, dimethylarsine and trimethylarsine) were described by a first order exponential equation of the form Ct = Co (1-e-kt).

  14. [Influence of predominant aerobic bacteria isolated from different healthy animals on daidzein biotransforming capacity by co-culture with different daidzein biotransforming bacteria].

    PubMed

    Luo, Jinglong; Wang, Xiuling; Fan, Jinru; Wang, Shiying; Li, Jia

    2011-08-01

    To investigate the influence of isolated predominant aerobic bacteria on daidzein biotransformation capacity by co-culture with daidzein biotransforming bacteria. Predominant aerobic bacteria were isolated from diluted feces solutions of different healthy animals, including ICR mice, Luhua chicken, Landrace pigs and Rex rabbits. Daidzein biotransforming bacteria were anaerobically co-cultured with the isolated predominant aerobic bacteria and the cultural broth was extracted and detected by high performance liquid chromatography (HPLC). Twenty two predominant aerobic bacteria were isolated from the four different healthy animals mentioned above. Based on the analyses of 16S rRNA gene sequences, morphology study and relative biophysico-biochemical characteristics, all 22 isolates belong to the 5 genera, i. e. Escherichia (10) , Proteus (5) , Enterococcus (4), Bacillus (2) and Pseudomonas (1). Co-culture between predominant aerobic bacteria and daidzein biotransforming bacteria was carried out under anaerobic conditions. The results showed that the biotransformation capacity was totally lost when different daidzein biotransforming bacterium was co-cultured with either Bacillus cereus ( R1 ) or Pseudomonas aerginosa (R5) and continuously inoculated for 2 or 3 passages. However, no obvious influence was observed when daidzein biotransforming bacteria were co-cultured with all the other isolated predominant aerobic bacteria except R1 and R5. In addition, when strain R1 and R5 was co-cultured with the intestinal microflora of the ICR mice anaerobically and continuously inoculated for 5 passages, about 90% of the co-cultures totally lost the activity to convert daidzein to equol effectively. Different predominant aerobic bacteria showed different influence on daidzein biotransformation capacity after being co-cultured with different daidzein biotransforming bacteria. Among all the isolated predominant aerobic bacteria used for co-culture, both Bacillus cereus ( R1) and

  15. Indoxacarb biotransformation in the German cockroach.

    PubMed

    Gondhalekar, Ameya D; Nakayasu, Ernesto S; Silva, Isabel; Cooper, Bruce; Scharf, Michael E

    2016-11-01

    Insecticides that are used for pest control undergo physical and biological (enzymatic) degradation. Indoxacarb is an oxadiazine class sodium channel blocker insecticide used for German cockroach (Blattella germanica L.) control. At present, no information is available on enzymatic biotransformation or metabolism of indoxacarb in this important urban pest. We studied the biotransformation pathways of indoxacarb in one susceptible and three field strains with varying susceptibility levels using liquid chromatography and high-resolution mass spectrometry. As shown in other insect species we found evidence for hydrolase-based bioactivation of indoxacarb to a toxic decarbomethoxylated metabolite, DCJW. In addition, both indoxacarb and DCJW were further metabolized to hydroxy, oxadiazine ring-opened and hydroxylated ring-opened metabolites. In general, higher indoxacarb disappearance, increased formation of DCJW and the above-mentioned metabolites were observed in the three field strains. In vitro biotransformation studies showed that hydroxylated and oxadiazine ring-opened metabolite formation is NADPH/cytochrome P450-dependent. Bioassays and in vivo metabolism experiments using the enzyme-inhibiting insecticide synergists, piperonyl butoxide (PBO) and S,S,S,-tributyl phosphorotrithioate (DEF), provided insights into potential indoxacarb resistance mechanisms that may proliferate in German cockroach field strains following unchecked selection pressures. The information presented here is an essential step toward developing indoxacarb resistance management programs and also reveals mechanisms of secondary/tertiary indoxacarb toxicity.

  16. Study of lignin biotransformation by Aspergillus fumigatus and white-rot fungi using /sup 14/C-labeled and unlabeled kraft lignins

    SciTech Connect

    Kadam, K.K.; Drew, S.W.

    1986-01-01

    The biodegradation of lignin by fungi was studied in shake flasks using /sup 14/C-labeled kraft lignin and in a deep-tank fermentor using unlabeled kraft lignin. Among the fungi screened, A. fumigatus - isolated in our laboratories - was most potent in lignin biotransformation. Dialysis-type fermentation, designed to study possible accumulation of low MW lignin-derived products, showed no such accumulation. Recalcitrant carbohydrates like microcrystalline cellulose supported higher lignolytic activity than easily metabolized carbohydrates like cellobiose. An assay developed to distinguish between CO/sub 2/ evolved from lignin and carbohydrate substrates demonstrated no stoichiometric correlation between the metabolism of the two cosubstrates. The submerged fermentations with unlabeled liqnin are difficult to monitor since chemical assays do not give accurate and true results. Lignolytic efficiencies that allowed monitoring of such fermentations were defined. Degraded lignins were clearly superior to C. versicolor in all aspects of lignin degradation; A fumigatus brought about substantial demethoxylation and dehydroxylation, whereas C. versicolor degraded lignins closely resembled undegraded kraft lignin. There was a good agreement among the different indices of lignin degradation, namely, /sup 14/CO evolution, OCH/sub 3/ loss, OH loss, and monomer and dimer yield after permanganate oxidation.

  17. Generation of Perfluoroalkyl Acids from Aerobic Biotransformation of Quaternary Ammonium Polyfluoroalkyl Surfactants.

    PubMed

    Mejia-Avendaño, Sandra; Vo Duy, Sung; Sauvé, Sébastien; Liu, Jinxia

    2016-09-20

    The aerobic biotransformation over 180 days of two cationic quaternary ammonium compounds (QACs) with perfluoroalkyl chains was determined in soil microcosms, and biotransformation pathways were proposed. This is the first time that polyfluoroalkyl cationic surfactants used in aqueous film-forming foam (AFFF) formulations were studied for their environmental fate. The biotransformation of perfluorooctaneamido quaternary ammonium salt (PFOAAmS) was characterized by a DT50 value (time necessary to consume half of the initial mass) of 142 days and significant generation of perfluoroalkyl carboxylic acid (PFOA) at a yield of 30 mol % by day 180. The biotransformation of perfluorooctane sulfonamide quaternary ammonium salt (PFOSAmS) was very slow with unobservable change of the spiked mass; yet the generation of perfluorooctanesulfonate (PFOS) at a yield of 0.3 mol % confirmed the biotransformation of PFOSAmS. Three novel biotransformation intermediates were identified for PFOAAmS and three products including perfluorooctane sulfonamide (FOSA) for PFOSAmS through high-resolution mass spectrometry (MS) analysis and t-MS(2) fragmentation. The significantly slower PFOSAmS biotransformation is hypothesized to be due to its stronger sorption to soil owing to a longer perfluoroalkyl chain and a bulkier sulfonyl group, when compared to PFOAAmS. This study has demonstrated that despite overall high stability of QACs and their biocide nature, the ones with perfluoroalkyl chains can be substantially biotransformed into perfluoroalkyl acids in aerobic soil.

  18. Adsorption, inhibition, and biotransformation of ciprofloxacin under aerobic conditions.

    PubMed

    Liu, Zhanguang; Sun, Peizhe; Pavlostathis, Spyros G; Zhou, Xuefei; Zhang, Yalei

    2013-09-01

    The adsorption, inhibition, and biotransformation of the fluoroquinolone antibiotic ciprofloxacin (CIP) under aerobic conditions were investigated in this study. The maximum adsorption capacity and the Langmuir constant were 37.9 mg CIP/g VSS and 37 L/g, respectively. A glucose-fed aerobic culture was inhibited by CIP at 10mg/L or higher and the degree of inhibition increased with increasing CIP concentration. However, the microbial activity recovered to some extent with prolonged incubation under a semi-continuous feeding mode. A low extent of CIP biotransformation was observed in an aerobic, glucose-fed culture derived from poultry litter extract. LC/UV/MS analysis of the biotransformation product showed that only the piperazine ring was oxidized, while the antibiotic quinolone part of CIP was intact. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Recent trends and novel concepts in cofactor-dependent biotransformations.

    PubMed

    Kara, Selin; Schrittwieser, Joerg H; Hollmann, Frank; Ansorge-Schumacher, Marion B

    2014-02-01

    Cofactor-dependent enzymes catalyze a broad range of synthetically useful transformations. However, the cofactor requirement also poses economic and practical challenges for the application of these biocatalysts. For three decades, considerable research effort has been devoted to the development of reliable in situ regeneration methods for the most commonly employed cofactors, particularly NADH and NADPH. Today, researchers can choose from a plethora of options, and oxidoreductases are routinely employed even on industrial scale. Nevertheless, more efficient cofactor regeneration methods are still being developed, with the aim of achieving better atom economy, simpler reaction setups, and higher productivities. Besides, cofactor dependence has been recognized as an opportunity to confer novel reactivity upon enzymes by engineering their cofactors, and to couple (redox) biotransformations in multi-enzyme cascade systems. These novel concepts will help to further establish cofactor-dependent biotransformations as an attractive option for the synthesis of biologically active compounds, chiral building blocks, and bio-based platform molecules.

  20. Pushing the Employment Agenda: Case Study Research of High Performing States in Integrated Employment

    ERIC Educational Resources Information Center

    Hall, Allison Cohen; Butterworth, John; Winsor, Jean; Gilmore, Dana; Metzel, Deborah

    2007-01-01

    Organizational variables, including policies, practices, collaborations, and funding mechanisms resulting in high performance in integrated employment, were described through case study research in 3 states. Findings address how contextual factors, system-level strategies, and goals of the system are related as well as how they sustain systems…

  1. A Case Study: Employment Prospects for Female Technology Graduates.

    ERIC Educational Resources Information Center

    Frey, Dewayne L.

    1978-01-01

    Findings from a three-year study to determine the ratio of male and female graduates employed in industrial-related jobs after completing industrial technology programs at Black Hawk College, Moline, Illinois, show no significant difference in the employability rate. Several factors may limit the study validity. (MF)

  2. A Case Study: Employment Prospects for Female Technology Graduates.

    ERIC Educational Resources Information Center

    Frey, Dewayne L.

    1978-01-01

    Findings from a three-year study to determine the ratio of male and female graduates employed in industrial-related jobs after completing industrial technology programs at Black Hawk College, Moline, Illinois, show no significant difference in the employability rate. Several factors may limit the study validity. (MF)

  3. Enzymatic biotransformation of terpenes as bioactive agents.

    PubMed

    Sultana, Nighat; Saify, Zafar Saeed

    2013-12-01

    The plant-derived terpenoids are considered to be the most potent anticancer, anti-inflammatory and anticarcinogenic compounds known. Enzymatic biotransformation is a very useful approach to expand the chemical diversity of natural products. Recent enzymatic biotransformation studies on terpenoids have resulted in the isolation of novel compounds. 14-hydroxy methyl caryophyllene oxide produced from caryophyllene oxide showed a potent inhibitory activity against the butyryl cholinesterase enzyme, and was found to be more potent than parent caryophyllene oxide. The metabolites 3β,7β-dihydroxy-11-oxo-olean-12-en-30-oic acid, betulin, betulonic acid, argentatin A, incanilin, 18β glycyrrhetinic acid, 3,11-dioxo-olean-12-en-30-oic acid produced from 18β glycyrrhetinic acid were screened against the enzyme lipoxygenase. 3,11-Dioxo-olean-12-en-30-oic acid, was found to be more active than the parent compound. The metabolites 3β-hydroxy sclareol 18α-hydroxy sclareol, 6α,18α-dihydroxy sclareol, 11S,18α-dihydroxy sclareol, and 1β-hydroxy sclareol and 11S,18α-dihydroxy sclareol produced from sclareol were screened for antibacterial activity. 1β-Hydroxy sclareol was found to be more active than parent sclareol. There are several reports on natural product enzymatic biotransformation, but few have been conducted on terpenes. This review summarizes the classification, advantages and agents of enzymatic transformation and examines the potential role of new enzymatically transformed terpenoids and their derivatives in the chemoprevention and treatment of other diseases.

  4. Biotransformation of phytosterols under aerobic conditions.

    PubMed

    Dykstra, Christy M; Giles, Hamilton D; Banerjee, Sujit; Pavlostathis, Spyros G

    2014-07-01

    Phytosterols are plant-derived sterols present in pulp and paper wastewater and have been implicated in the endocrine disruption of aquatic species. Bioassays were performed to assess the effect of an additional carbon source and/or solubilizing agent on the aerobic biotransformation of a mixture of three common phytosterols (β-sitosterol, stigmasterol and campesterol). The aerobic biotransformation of the phytosterol mixture by a mixed culture developed from a pulp and paper wastewater treatment system was examined under three separate conditions: with phytosterols as the sole added carbon source, with phytosterols and dextrin as an additional carbon source, and with phytosterols added with ethanol as an additional carbon source and solubilizing agent. Significant phytosterol removal was not observed in assays set up with phytosterol powder, either with or without an additional carbon source. In contrast, all three phytosterols were aerobically degraded when added as a dissolved solution in ethanol. Thus, under the experimental conditions of this study, the bioavailability of phytosterols was limited without the presence of a solubilizing agent. The total phytosterol removal rate was linear for the first six days before re-spiking, with a rate of 0.47 mg/L-d (R(2) = 0.998). After the second spiking, the total phytosterol removal rate was linear for seven days, with a rate of 0.32 mg/L-d (R(2) = 0.968). Following the 7th day, the phytosterol removal rate markedly accelerated, suggesting two different mechanisms are involved in phytosterol biotransformation, more likely related to the production of enzyme(s) involved in phytosterol degradation, induced under different cell growth conditions. β-sitosterol was preferentially degraded, as compared to stigmasterol and campesterol, although all three phytosterols fell below detection limits by the 24th day of incubation.

  5. Estimating intestinal absorption of inorganic and organic selenium compounds by in vitro flux and biotransformation studies in Caco-2 cells and ICP-MS detection.

    PubMed

    Gammelgaard, Bente; Rasmussen, Laura Hyrup; Gabel-Jensen, Charlotte; Steffansen, Bente

    2012-02-01

    The aim of the present work was to compare and estimate absorption and biotransformation of selected selenium compounds by studying their fluxes across Caco-2 cells. Five different selenium compounds, selenomethionine (SeMet), Se-methylselenocysteine (MeSeCys), selenate, selenite, and methylseleninic acid (MeSeA), were applied to Caco-2 cells in a concentration of 10 μM, and fluxes in both directions were studied for 2 h. Fluxes of selenite and MeSeA in the presence of excess reduced glutathione (selenite + GSH and MeSeA + GSH) and flux of MeSeA in the presence of excess cysteine (MeSeA + Cys) were also studied. Selenium absorptive and exsorptive fluxes and accumulation in cell cytosol were analyzed by means of flow injection inductively coupled plasma mass spectrometry (ICP-MS). Absorptive flux of SeMet, MeSeCys, and selenate showed values correlating to complete in vivo absorption, while selenite and MeSeA fluxes correlated to poor in vivo absorption. Speciation analysis of cell lysate and donor and receptor solutions by LC-ICP-MS showed limited transformation of all selenium compounds. Extensive transformation as well as significantly increased absorptive flux was observed when co-administering selenite with glutathione compared to administering selenite alone. These observations are possibly due to formation of selenodiglutathione (GS-Se-SG) which may be absorbed differently than selenite. Concomitant application of GSH or cysteine with MeSeA resulted in extensive transformation of MeSeA, including volatile species, whereas no significant increases in fluxes were observed. In summary, the absorption of selenite selenate and the selenoamino acids is considered complete under physiological conditions, but the absorption mechanisms and metabolism of the compounds are different.

  6. 2006-2008 Studies on the Employability of UKM Graduates

    ERIC Educational Resources Information Center

    Omar, Ramli; Khoon, Koh Aik; Hamzah, Mohd Fauzi; Ahmadan, Siti Rohayu

    2009-01-01

    This paper discusses the employability of UKM graduates in the job market from 2006-2008. Studies showed that the employability varied from discipline to discipline with the dentistry and medical graduates leading the pack. In recent years UKM graduates have made inroads into GLC's, a positive development indeed. (Contains 2 tables.)

  7. Enhancing the Employability of Newly Qualified Nurses: A Pilot Study

    ERIC Educational Resources Information Center

    Dray, Beattie; Burke, Linda; Hurst, Heather M.; Ferguson, Anne; Marks-Maran, Diane

    2011-01-01

    Vocationally based higher education programmes are meant to prepare people for employment in their chosen fields of study. In nursing, historically, employment after qualifying has been almost assured, with sufficient vacancies available for newly qualified nurses. Recently, however, for a number of reasons, primarily related to economic…

  8. 2006-2008 Studies on the Employability of UKM Graduates

    ERIC Educational Resources Information Center

    Omar, Ramli; Khoon, Koh Aik; Hamzah, Mohd Fauzi; Ahmadan, Siti Rohayu

    2009-01-01

    This paper discusses the employability of UKM graduates in the job market from 2006-2008. Studies showed that the employability varied from discipline to discipline with the dentistry and medical graduates leading the pack. In recent years UKM graduates have made inroads into GLC's, a positive development indeed. (Contains 2 tables.)

  9. Biotransformation of pesticides in saturated-zone materials

    NASA Astrophysics Data System (ADS)

    Hoyle, Blythe L.; Arthur, Ellen L.

    Many studies have been conducted to evaluate pesticide contamination of groundwater in the United States, but investigations of pesticide biotransformation in saturated zones are much less numerous than in surface soils. Because results of studies using soils are not directly applicable to the subsurface, the purpose of this paper is to illustrate examples of pesticide biotransformation in saturated-zone materials. Although it must be considered with caution, the US Environmental Protection Agency's (EPA) "Pesticides in Ground Water Database" was used to focus the discussion on the biotransformation potential of dibromoethane (EDB), atrazine, acetanilide herbicides, and aldicarb, all of which have been detected in groundwater in the United States. Results of more than two dozen studies indicate that a biotransformation potential for these pesticides exists in saturated-zone materials, although for any given pesticide substantial differences in biotransformation occurred. These variations were due both to differences in experimental methods and to heterogeneities in the subsurface materials under investigation. However, because biotransformation mechanisms were not well investigated, it is generally not possible to extrapolate predictions of biotransformation potential beyond the specific sites investigated. These results highlight the need to better understand microbial genetic regulation of biotransformation processes so that genetic information may be effectively incorporated into future investigations of biotransformation potential in the subsurface. Résumé De nombreuses études ont été réalisées pour évaluer le degré de pollution des aquifères par les pesticides aux États-Unis, mais les recherches concernant la biotransformation des pesticides dans les eaux souterraines sont beaucoup moins nombreuses que dans les sols. Du fait que les résultats des études concernant les sols ne sont pas directement applicables au milieu souterrain, le propos de cet

  10. Monitoring subcellular biotransformation of N-L-leucyldoxorubicin by micellar electrokinetic capillary chromatography coupled to laser-induced fluorescence detection.

    PubMed

    Satori, Chad P; Meyer, Brandon; Arriaga, Edgar A

    2014-04-01

    Development of prodrugs is a promising alternative to address cytotoxicity and nonspecificity of common anticancer agents. N-L-leucyldoxorubicin (LeuDox) is a prodrug that is biotransformed to the anticancer drug doxorubicin (Dox) in the extracellular space; however, its biotransformation may also occur intracellularly in endocytic organelles. Such organelle-specific biotransformation is yet to be determined. In this study, magnetically enriched endocytic organelle fractions from human uterine sarcoma cells were treated with LeuDox. Micellar electrokinetic chromatography with laser-induced fluorescence detection (MEKC-LIF) was used to determine that 10% of LeuDox was biotransformed to Dox, accounting for ~43% of the biotransformation occurring in the post-nuclear fraction. This finding suggests that endocytic organelles also participate in the intracellular biotransformation of LeuDox to Dox.

  11. Youth's Perceptions of Employer Hiring and Disciplinary Standards. Executive Summary. Employability Factors Study. Studies in Employment and Training Policy: No. 2.

    ERIC Educational Resources Information Center

    Miguel, Richard J.

    A study focused on the relationships of (1) youth's perceptions of hiring and disciplinary standards, (2) their work supervisors' reports of those standards, and (3) selected antecedents and employment outcomes associated with employability development programs. Through questionnaires, data were collected at the beginning and end of the 1981-82…

  12. Employers' views of promoting walking to work: a qualitative study.

    PubMed

    Audrey, Suzanne; Procter, Sunita

    2015-02-11

    Physical inactivity increases the risk of many chronic diseases including coronary heart disease, type 2 diabetes, obesity and some cancers. It is currently recommended that adults should undertake at least 150 minutes of moderate physical activity in bouts of 10 minutes or more throughout the week. One way for adults in employment to incorporate exercise into their daily routine is to walk during the commute to and from work. Schemes to promote active travel require the support of employers and managers but there is a lack of research focusing on their views and experiences of promoting walk to work schemes. This study presents the findings from in-depth, digitally recorded interviews with 29 employers from a range of small, medium and large workplaces who participated in a feasibility study to develop and test an employer-led scheme to promote walking to work. All recordings were fully transcribed. The Framework approach for data management was used to aid qualitative analysis. Interview transcripts were read and reread, and textual data were placed in charts focusing on facilitators, barriers, and possibilities for employers to promote walking to work. A range of perspectives were identified, from active support through uncertainty and cynicism to resistance. The majority of employers who took part in the study were unclear about how to give practical support for employees who walk to work, but appeared more confident about ideas to promote cycling. Some employers were concerned about how their attempts to promote walking might be perceived by employees. Furthermore, the main business of their organisation took priority over other activities. It is clear that employers need more evidence of the effectiveness of walk to work schemes, and the benefits to employers of committing resources to them. Furthermore, employers need support in creating an authentic, health promoting ethos within the workplace to enhance positive relationships and reduce tensions that may

  13. Employment among Patients with Multiple Sclerosis-A Population Study

    PubMed Central

    Bøe Lunde, Hanne Marie; Telstad, Wenche; Grytten, Nina; Kyte, Lars; Aarseth, Jan; Myhr, Kjell-Morten; Bø, Lars

    2014-01-01

    Objective To investigate demographic and clinical factors associated with employment in MS. Methods The study included 213 (89.9%) of all MS patients in Sogn and Fjordane County, Western Norway at December 31st 2010. The patients underwent clinical evaluation, structured interviews and completed self-reported questionnaires. Demographic and clinical factors were compared between patients being employed versus patients being unemployed and according to disease course of MS. Logistic regression analysis was used to identify factors independently associated with current employment. Results After a mean disease duration of almost 19 years, 45% of the population was currently full-time or part- time employed. Patients with relapsing –remitting MS (RRMS) had higher employment rate than patients with secondary (SPMS) and primary progressive (PPMS). Higher educated MS patients with lower age at onset, shorter disease duration, less severe disability and less fatigue were most likely to be employed. Conclusions Nearly half of all MS patients were still employed after almost two decades of having MS. Lower age at onset, shorter disease duration, higher education, less fatigue and less disability were independently associated with current employment. These key clinical and demographic factors are important to understand the reasons to work ability in MS. The findings highlight the need for environmental adjustments at the workplace to accommodate individual ’s needs in order to improve working ability among MS patients. PMID:25054972

  14. Incorporating Human Interindividual Biotransformation ...

    EPA Pesticide Factsheets

    The protection of sensitive individuals within a population dictates that measures other than central tendencies be employed to estimate risk. The refinement of human health risk assessments for chemicals metabolized by the liver to reflect data on human variability can be accomplished through (1) the characterization of enzyme expression in large banks of human liver samples, (2) the employment of appropriate techniques for the quantification and extrapolation of metabolic rates derived in vitro, and (3) the judicious application of physiologically based pharmacokinetic (PBPK) modeling. While in vitro measurements of specific biochemical reactions from multiple human samples can yield qualitatively valuable data on human variance, such measures must be put into the perspective of the intact human to yield the most valuable predictions of metabolic differences among humans. For quantitative metabolism data to be the most valuable in risk assessment, they must be tied to human anatomy and physiology, and the impact of their variance evaluated under real exposure scenarios. For chemicals metabolized in the liver, the concentration of parent chemical in the liver represents the substrate concentration in the MichaelisMenten description of metabolism. Metabolic constants derived in vitro may be extrapolated to the intact liver, when appropriate conditions are met. Metabolic capacity Vmax; the maximal rate of the reaction) can be scaled directly to the concentration

  15. What's a Good Job? The Importance of Employment Relationships. CPRN Study. Changing Employment Relationships Series.

    ERIC Educational Resources Information Center

    Lowe, Graham S.; Schellenberg, Grant

    The Changing Employment Relationships Project examined the importance of good employment relationships for workers, employers, and public policy. A nationally representative sample of 2,500 employed Canadians was surveyed, and 8 focus groups were conducted. The research findings were analyzed to explain the multidimensional nature of the…

  16. Aerobic activated sludge transformation of methotrexate: identification of biotransformation products.

    PubMed

    Kosjek, Tina; Negreira, Noelia; de Alda, Miren López; Barceló, Damià

    2015-01-01

    This study describes the biotransformation of cytostatic and immunosuppressive pharmaceutical methotrexate. Its susceptibility to microbiological breakdown was studied in a batch biotransformation system, in presence or absence of carbon source and at two activated sludge concentrations. The primary focus of the present study are methotrexate biotransformation products, which were tentatively identified by the ultra-high performance liquid chromatography-quadrupole--Orbitrap-MS. Data-dependent experiments, combining full-scan MS data with product ion spectra were acquired, in order to identify the molecular ions of methotrexate transformation products, to propose the molecular formulae and to elucidate their chemical structures. Among the identified transformation products 2,4-diamino-N10-methyl-pteroic acid is most abundant and persistent. Other biotransformation reactions involve demethylation, oxidative cleavage of amine, cleavage of C-N bond, aldehyde to carboxylate transformation and hydroxylation. Finally, a breakdown pathway is proposed, which shows that most of methotrexate breakdown products retain the diaminopteridine structural segment. In total we propose nine transformation products, among them eight are described as methotrexate transformation products for the first time.

  17. Development of human biotransformation QSARs and application for PBT assessment refinement.

    PubMed

    Papa, Ester; Sangion, Alessandro; Arnot, Jon A; Gramatica, Paola

    2017-04-13

    Toxicokinetics heavily influence chemical toxicity as the result of Absorption, Distribution, Metabolism (Biotransformation) and Elimination (ADME) processes. Biotransformation (metabolism) reactions can lead to detoxification or, in some cases, bioactivation of parent compounds to more toxic chemicals. Moreover, biotransformation has been recognized as a key process determining chemical half-life in an organism and is thus a key determinant for bioaccumulation assessment for many chemicals. This study addresses the development of QSAR models for the prediction of in vivo whole body human biotransformation (metabolism) half-lives measured or empirically-derived for over 1000 chemicals, mainly represented by pharmaceuticals. Models presented in this study meet regulatory standards for fitting, validation and applicability domain. These QSARs were used, in combination with literature models for the prediction of biotransformation half-lives in fish, to refine the screening of the potential PBT behaviour of over 1300 Pharmaceuticals and Personal Care Products (PPCPs). The refinement of the PBT screening allowed, among others, for the identification of PPCPs, which were predicted as PBTs on the basis of their chemical structure, but may be easily biotransformed. These compounds are of lower concern in comparison to potential PBTs characterized by large predicted biotransformation half-lives. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. ANAEROBIC BIOTRANSFORMATION OF 2,4-DINITROTOLUENE WITH ETHANOL AS PRIMARY SUBSTRATE: MUTUAL EFFECT OF THE SUBSTRATES ON THEIR BIOTRANSFORMATION

    EPA Science Inventory

    The effect of the initial concentration of 2,4-dinitrotoluene (DNT) on its biotransformation and on the microbial utilization of ethanol was investigated. The culture used in this study was acclimated in a continuous flow laboratory fermentor with 2,4-DNT and ethanol as substrat...

  19. ANAEROBIC BIOTRANSFORMATION OF 2,4-DINITROTOLUENE WITH ETHANOL AS PRIMARY SUBSTRATE: MUTUAL EFFECT OF THE SUBSTRATES ON THEIR BIOTRANSFORMATION

    EPA Science Inventory

    The effect of the initial concentration of 2,4-dinitrotoluene (DNT) on its biotransformation and on the microbial utilization of ethanol was investigated. The culture used in this study was acclimated in a continuous flow laboratory fermentor with 2,4-DNT and ethanol as substrat...

  20. Comparison in antioxidant and antitumor activities of pine polyphenols and its seven biotransformation extracts by fungi

    PubMed Central

    Li, Hui

    2017-01-01

    Microbial transformation can strengthen the antioxidant and antitumor activities of polyphenols. Polyphenols contents, antioxidant and antitumor activities of pine polyphenols and its biotransformation extracts by Aspergillus niger, Aspergillus oryzae, Aspergillus carbonarius, Aspergillus candidus, Trichodermas viride, Mucor wutungkiao and Rhizopus sp were studied. Significant differences were noted in antioxidant and antitumor activities. The highest antioxidant activities in Trolox equivalent antioxidant capacity (TEAC), DPPH radical scavenging activity, superoxide anion radical scavenging activity, hydroxyl radical scavenging activity, reducing power assay and antitumor activity against LoVo cells were biotransformation extract of Aspergillus carbonarius (BAC), biotransformation extract of Mucor wutungkiao (BMW), biotransformation extract of Aspergillus carbonarius (BAC), biotransformation extract of Aspergillus niger (BAN), biotransformation extract of Aspergillus oryzae (BAO) and BMW, respectively. Correlation analysis found that antioxidant and antitumor activities were associated with polyphenols contents and types of free radicals and tumors. A. carbonarius can make polyphenol oxidation, hydroxylation and methylation, and form new polyphenols. In conclusion, A. carbonarius, A. niger and M. wutungkiao are valuable microorganisms used for polyphenols biotransformation and enhance the antioxidant and antitumor activities of polyphenols. PMID:28560092

  1. Biotransformation of selected iodinated X-ray contrast media and characterization of microbial transformation pathways.

    PubMed

    Kormos, Jennifer Lynne; Schulz, Manoj; Kohler, Hans-Peter E; Ternes, Thomas A

    2010-07-01

    Iodinated X-ray contrast media (ICM) are commonly detected in the aquatic environment at concentrations up to the low microgram per liter range. In this study, the biotransformation of selected ICM (diatrizoate, iohexol, iomeprol, and iopamidol) in aerobic soil-water and river sediment-water batch systems was investigated. In addition, microbial transformation pathways were proposed. Diatrizoate, an ionic ICM, was not biotransformed, while three nonionic ICM were transformed into several biotransformation products (TPs) at neutral pH. Iohexol and iomeprol were biotransformed to eleven TPs and fifteen TPs, respectively, while eight TPs were detected for iopamidol. Since seven of the TPs detected during biotransformation had not been previously identified, mass fragmentation experiments were completed to elucidate the chemical structures. Oxidation of primary alcoholic moieties, cleavage of the N-C bonds (i.e., deacetylation and removal of hydroxylated propanoic acids), and decarboxylation are potential reactions that can explain the formation of the identified TPs. Iohexol and iomeprol had similar biotransformation rates, while iopamidol was biotransformed slower and to a lesser extent. A LC tandem MS method confirmed the presence of ICM TPs in aqueous environmental samples. Fifteen of the ICM TPs were even detected in drinking water with concentrations up to 120 ng/L.

  2. Biotransformation of Two Pharmaceuticals by the Ammonia-Oxidizing Archaeon Nitrososphaera gargensis

    PubMed Central

    2016-01-01

    The biotransformation of some micropollutants has previously been observed to be positively associated with ammonia oxidation activities and the transcript abundance of the archaeal ammonia monooxygenase gene (amoA) in nitrifying activated sludge. Given the increasing interest in and potential importance of ammonia-oxidizing archaea (AOA), we investigated the capabilities of an AOA pure culture, Nitrososphaera gargensis, to biotransform ten micropollutants belonging to three structurally similar groups (i.e., phenylureas, tertiary amides, and tertiary amines). N. gargensis was able to biotransform two of the tertiary amines, mianserin (MIA) and ranitidine (RAN), exhibiting similar compound specificity as two ammonia-oxidizing bacteria (AOB) strains that were tested for comparison. The same MIA and RAN biotransformation reactions were carried out by both the AOA and AOB strains. The major transformation product (TP) of MIA, α-oxo MIA was likely formed via a two-step oxidation reaction. The first hydroxylation step is typically catalyzed by monooxygenases. Three RAN TP candidates were identified from nontarget analysis. Their tentative structures and possible biotransformation pathways were proposed. The biotransformation of MIA and RAN only occurred when ammonia oxidation was active, suggesting cometabolic transformations. Consistently, a comparative proteomic analysis revealed no significant differential expression of any protein-encoding gene in N. gargensis grown on ammonium with MIA or RAN compared with standard cultivation on ammonium only. Taken together, this study provides first important insights regarding the roles played by AOA in micropollutant biotransformation. PMID:27046099

  3. PILOT STUDIES OF IN-SITU BIO-TRANSFORMATION OF MERCURY-CONTAMINATED GROUNDWATER IN KAZAKHSTAN UTILIZING NATIVE BACTERIA

    EPA Science Inventory

    Several regions in the Republic of Kazakhstan and throughout the former USSR are contaminated with mercury resulting from industrial releases. Our studies directed towards determining the feasibility of developing a biological filter, which when placed into the path the groundwat...

  4. PILOT STUDIES OF IN-SITU BIO-TRANSFORMATION OF MERCURY-CONTAMINATED GROUNDWATER IN KAZAKHSTAN UTILIZING NATIVE BACTERIA

    EPA Science Inventory

    Several regions in the Republic of Kazakhstan and throughout the former USSR are contaminated with mercury resulting from industrial releases. Our studies directed towards determining the feasibility of developing a biological filter, which when placed into the path the groundwat...

  5. Frailty, prefrailty and employment outcomes in Health and Employment After Fifty (HEAF) Study.

    PubMed

    Palmer, Keith T; D'Angelo, Stefania; Harris, E Clare; Linaker, Cathy; Gale, Catharine R; Evandrou, Maria; Syddall, Holly; van Staa, Tjeerd; Cooper, Cyrus; Aihie Sayer, Avan; Coggon, David; Walker-Bone, Karen

    2017-07-01

    Demographic changes are requiring people to work longer. No previous studies, however, have focused on whether the 'frailty' phenotype (which predicts adverse events in the elderly) is associated with employment difficulties. To provide information, we assessed associations in the Health and Employment After Fifty Study, a population-based cohort of 50-65-year olds. Subjects, who were recruited from 24 English general practices, completed a baseline questionnaire on 'prefrailty' and 'frailty' (adapted Fried criteria) and several work outcomes, including health-related job loss (HRJL), prolonged sickness absence (>20 days vs less, past 12 months), having to cut down substantially at work and difficulty coping with work's demands. Associations were assessed using logistic regression and population attributable fractions (PAFs) were calculated. In all, 3.9% of 8095 respondents were classed as 'frail' and 31.6% as 'prefrail'. Three-quarters of the former were not in work, while 60% had left their last job on health grounds (OR for HRJL vs non-frail subjects, 30.0 (95% CI 23.0 to 39.2)). Among those in work, ORs for prolonged sickness absence, cutting down substantially at work and struggling with work's physical demands ranged from 10.7 to 17.2. The PAF for HRJL when any frailty marker was present was 51.8% and that for prolonged sickness absence was 32.5%. Associations were strongest with slow reported walking speed. Several associations were stronger in manual workers than in managers. Fried frailty symptoms are not uncommon in mid-life and are strongly linked with economically important adverse employment outcomes. Frailty could represent an important target for prevention. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  6. Do Study Abroad Programs Enhance the Employability of Graduates?

    ERIC Educational Resources Information Center

    Di Pietro, Giorgio

    2015-01-01

    Using data on a large sample of recent Italian graduates, this paper investigates the extent to which participation in study abroad programs during university studies impacts subsequent employment likelihood. To address the problem of endogeneity related to participation in study abroad programs, I use a combination of fixed effects and…

  7. Do Study Abroad Programs Enhance the Employability of Graduates?

    ERIC Educational Resources Information Center

    Di Pietro, Giorgio

    2015-01-01

    Using data on a large sample of recent Italian graduates, this paper investigates the extent to which participation in study abroad programs during university studies impacts subsequent employment likelihood. To address the problem of endogeneity related to participation in study abroad programs, I use a combination of fixed effects and…

  8. Biotransformation of chloromethane to methanethiol

    SciTech Connect

    Braus-Stromeyer, S.A.; Cook, A.M.; Leisinger, T. )

    1993-08-01

    Monochloromethane (MeCl) was biotransformed by a mixed culture of anaerobic bacteria which had been enriched to utilize dichloromethane as the sole source of carbon and energy. Cells grown in dichloromethane-salts medium catalyzed the transformation, whereas sucrose-grown cells were inactive. MeCl disappeared almost totally, and the methyl group was recovered in a yield of 80-90% as methanethiol and traces of dimethyl sulfide, whose identities were confirmed by GC-MS. The methyl transfer was heat-labile, and free aquocobalamin did not promote the reaction, which was apparently enzymically catalyzed. 37 refs., 1 fig., 2 tabs.

  9. Isotopic effects in mechanistic studies of biotransformations of fluorine derivatives of L-alanine catalysed by L-alanine dehydrogenase.

    PubMed

    Szymańska-Majchrzak, Jolanta; Pałka, Katarzyna; Kańska, Marianna

    2017-05-01

    Synthesis of 3-fluoro-[2-(2)H]-L-alanine (3-F-[(2)H]-L-Ala) in reductive amination of 3-fluoropyruvic acid catalysed by L-alanine dehydrogenase (AlaDH) was described. Fluorine derivative was used to study oxidative deamination catalysed by AlaDH applied kinetic (for 3-F-L-Ala in H2O - KIE's on Vmax: 1.1; on Vmax/KM: 1.2; for 3-F-L-Ala in (2)H2O - on Vmax: 1.4; on Vmax/KM: 2.1) and solvent isotope effect methods (for 3-F-L-Ala - SIE's on Vmax: 1.0; on Vmax/KM: 0.87; for 3-F-[2-(2)H]-L-Ala - on Vmax: 1.4; on Vmax/KM: 1.5). Studies explain some details of reaction mechanism. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. A mass balance study to evaluate the biotransformation and excretion of [14C]-triamcinolone acetonide following oral administration.

    PubMed

    Argenti, D; Jensen, B K; Hensel, R; Bordeaux, K; Schleimer, R; Bickel, C; Heald, D

    2000-07-01

    The principle objective of this study was to characterize the absorption, metabolism, and disposition of orally administered [14C]-triamcinolone acetonide. Six healthy male subjects each received a single 100 microCi (approximately 800 micrograms) oral dose of [14C]-triamcinolone acetonide. Plasma, urine, and fecal samples were collected at selected times and analyzed for triamcinolone acetonide and [14C]-derived radioactivity. Plasma protein binding of triamcinolone acetonide was also determined. Metabolite profiling and identification were carried out in plasma and excreta. Principle metabolites were assessed for activity with in vitro anti-inflammatory models. [14C]-triamcinolone acetonide was found to be systemically absorbed following oral administration. The presystemic metabolism and clearance of triamcinolone acetonide were extensive, with only a small fraction of the total plasma radioactivity being made up of triamcinolone acetonide. Little to no parent compound was detected in the plasma 24 hours after administration. Most of the urinary and fecally [14C]-derived radioactivity was also excreted within 24 and 72 hours postdose, respectively. Mean plasma protein binding of triamcinolone acetonide was constant, predictable, and a relatively low 68% over a 24-fold range of plasma concentrations. Three principle metabolites of triamcinolone acetonide were profiled in plasma, urine, and feces. These metabolites were identified as 6 beta-hydroxy triamcinolone, 21-carboxylic acid triamcinolone acetonide, and 6 beta-hydroxy-21-oic triamcinolone acetonide. All three metabolites failed to show any concentration-dependent effects in anti-inflammatory models evaluating IL-5-sustained eosinophil viability and IgE-induced basophil histamine release.

  11. Employment Retention after Vision Loss: Intensive Case Studies.

    ERIC Educational Resources Information Center

    Crudden, Adele; Fireison, Cara K.

    This study examined the lives of 10 individuals with blindness or severe visual impairment who maintained competitive employment despite their vision loss. The study was designed to provide information regarding the personal characteristics and current practices related to work environment alterations which enhance competitive employment…

  12. EFFECTS OF ANESTHESIA (MS222) ON LIVER BIOTRANSFORMATION IN RAINBOW TROUT (ONCORHYNCHUS MYKISS)

    EPA Science Inventory

    Tricaine methanesulfonate (3-aminobenzoic acid ethyl ester methanesulfonate; MS222) is a widely used fish anaesthetic. While there have been several studies addressing the impact of its use on subsequently measured biotransformation rates, the measured influence on normal functio...

  13. ALTERATIONS IN SEXUALLY DIMORPHIC BIOTRANSFORMATION OF TESTOSTERONE IN JUVENILE AMERICAN ALLIGATORS (ALLIGATOR MISSISSIPPIENSIS) FROM CONTAMINATED LAKES

    EPA Science Inventory

    The goal of this study was to determine whether hepatic biotransformation of testosterone is normally sexually dimorphic in juvenile alligators and whether living in a contaminated environment affects hepatic dimorphism. Lake Woodruff served as our reference site. Moonshine Bay, ...

  14. EFFECTS OF ANESTHESIA (MS222) ON LIVER BIOTRANSFORMATION IN RAINBOW TROUT (ONCORHYNCHUS MYKISS)

    EPA Science Inventory

    Tricaine methanesulfonate (3-aminobenzoic acid ethyl ester methanesulfonate; MS222) is a widely used fish anaesthetic. While there have been several studies addressing the impact of its use on subsequently measured biotransformation rates, the measured influence on normal functio...

  15. ALTERATIONS IN SEXUALLY DIMORPHIC BIOTRANSFORMATION OF TESTOSTERONE IN JUVENILE AMERICAN ALLIGATORS (ALLIGATOR MISSISSIPPIENSIS) FROM CONTAMINATED LAKES

    EPA Science Inventory

    The goal of this study was to determine whether hepatic biotransformation of testosterone is normally sexually dimorphic in juvenile alligators and whether living in a contaminated environment affects hepatic dimorphism. Lake Woodruff served as our reference site. Moonshine Bay, ...

  16. A Longitudinal Study of Work After Retirement: Examining Predictors of Bridge Employment, Continued Career Employment, and Retirement.

    PubMed

    Bennett, Misty M; Beehr, Terry A; Lepisto, Lawrence R

    2016-09-01

    Older employees are increasingly accepting bridge employment, which occurs when older workers take employment for pay after they retire from their main career. This study examined predictors of workers' decisions to engage in bridge employment versus full retirement and career employment. A national sample of 482 older people in the United States was surveyed regarding various work-related and nonwork related predictors of retirement decisions, and their retirement status was measured 5 years later. In bivariate analyses, both work-related variables (career goal achievement and experienced pressure to retire) and nonwork-related variables (psychological distress and traditional gender role orientation) predicted taking bridge employment, but in multinomial logistic regression, only nonwork variables had unique effects. Few predictors differentiated the bridge employed and fully retired groups. Nonwork variables were salient in making the decision to retire, and bridge employment may be conceptually more similar to full retirement than to career employment. © The Author(s) 2016.

  17. Enantioselective biotransformations of nitriles in organic synthesis.

    PubMed

    Wang, Mei-Xiang

    2015-03-17

    The hydration and hydrolysis of nitriles are valuable synthetic methods used to prepare carboxamides and carboxylic acids. However, chemical hydration and hydrolysis of nitriles involve harsh reaction conditions, have low selectivity, and generate large amounts of waste. Therefore, researchers have confined the scope of these reactions to simple nitrile substrates. However, biological transformations of nitriles are highly efficient, chemoselective, and environmentally benign, which has led synthetic organic chemists and biotechologists to study these reactions in detail over the last two decades. In nature, biological systems degrade nitriles via two distinct pathways: nitrilases catalyze the direct hydrolysis of nitriles to afford carboxylic acids with release of ammonia, and nitrile hydratases catalyze the conversion of nitriles into carboxamides, which then furnish carboxylic acids via hydrolysis in the presence of amidases. Researchers have subsequently developed biocatalytic methods into useful industrial processes for the manufacture of commodity chemicals, including acrylamide. Since the late 1990s, research by my group and others has led to enormous progress in the understanding and application of enantioselective biotransformations of nitriles in organic synthesis. In this Account, I summarize the important advances in enantioselective biotransformations of nitriles and amides, with a primary focus on research from my laboratory. I describe microbial whole-cell-catalyzed kinetic resolution of various functionalized nitriles, amino- and hydroxynitriles, and nitriles that contain small rings and the desymmetrization of prochiral and meso dinitriles and diamides. I also demonstrate how we can apply the biocatalytic protocol to synthesize natural products and bioactive compounds. These nitrile biotransformations offer an attractive and unique protocol for the enantioselective synthesis of polyfunctionalized organic compounds that are not readily obtainable by

  18. Pushing the employment agenda: case study research of high performing States in integrated employment.

    PubMed

    Hall, Allison Cohen; Butterworth, John; Winsor, Jean; Gilmore, Dana; Metzel, Deborah

    2007-06-01

    Organizational variables, including policies, practices, collaborations, and funding mechanisms resulting in high performance in integrated employment, were described through case study research in 3 states. Findings address how contextual factors, system-level strategies, and goals of the system are related as well as how they sustain systems change. Strategies such as flexibility in funding and practices; communication of values through data, rewards, and funding incentives; and innovation diffusion through relationships and training were most successful when they were embedded within the context of a solid values base, a network of dedicated stakeholders, and clarity about systemic goals. Implications are presented with respect to state systems, community rehabilitation providers as partners in planning, and future leadership in the field.

  19. [Access to equal employment: retrospective studies and perspectives].

    PubMed

    Tougas, F; Veilleux, F

    1991-09-01

    Reaching for more fair representation of women in all levels and in all areas of employment involves a fundamental change in mentalities and administrative practices. Following twenty years of efforts to improve women's situation, where are we now? Do men and women approve of the same strategies to eliminate sex discrimination? We will address these questions by relying on results obtained in the context of a research program developed at the University of Ottawa. The results of these studies lead us to question the human costs for women's slow access to employment equity.

  20. Focus:HOPE--A Case Study of a Sectoral Employment Development Approach. Sectoral Employment Development Learning Project Case Studies Series.

    ERIC Educational Resources Information Center

    Thompson, Jeffery W.; Turner-Meikeljohn, Susan; Conway, Maureen

    This case study on Focus: HOPE is the fourth of six sectoral studies to provide an in-depth look at individual sectoral employment development programs and their interaction within distinct economic and industry environments. It explores HOPE, a Detroit civil rights organization with a highly developed machinist training program. Section 1…

  1. A Study for Texas: Education, Employment and the Economy.

    ERIC Educational Resources Information Center

    Thomas, Wayne E.

    In this speech, the author proposes a comprehensive study of professional, industrial, and business employment needs, and of the relationship of these needs to educational programs and services in the state of Texas. The proposal for action addresses statewide concern for the current lack of correlation between educational programs and career…

  2. Formulating Employability Skills for Graduates of Public Health Study Program

    ERIC Educational Resources Information Center

    Qomariyah, Nurul; Savitri, Titi; Hadianto, Tridjoko; Claramita, Mora

    2016-01-01

    Employability skills (ES) are important for effective and successful individual participation in the workplace. The main aims of the research were to identify important ES needed by graduates of Public Health Study Program Universitas Ahmad Dahlan (PHSP UAD) and to assess the achievement of the ES development that has been carried out by PHSP UAD.…

  3. Employing Case Study Methodology in Special Educational Settings

    ERIC Educational Resources Information Center

    Rouse, Angelise M.

    2016-01-01

    In general, case studies are a preferred strategy when "how" or "why" questions are being posed, when the investigator has little control over events, and when the focus is on a contemporary phenomenon within some real-life context (Yin, 2009). This article will examine the advantages and disadvantages of employing case study…

  4. Employing Case Study Methodology in Special Educational Settings

    ERIC Educational Resources Information Center

    Rouse, Angelise M.

    2016-01-01

    In general, case studies are a preferred strategy when "how" or "why" questions are being posed, when the investigator has little control over events, and when the focus is on a contemporary phenomenon within some real-life context (Yin, 2009). This article will examine the advantages and disadvantages of employing case study…

  5. Problems of Eskimo Relocation for Industrial Employment. A Preliminary Study.

    ERIC Educational Resources Information Center

    Stevenson, D. S.

    A study was conducted to determine the reasons for variable success in relocating Eskimo families from rural areas of the northern territories of Canada to southern centers of industrial employment (railways, mining centers). The data were collected by interviewing 105 Eskimos, both male and female, married and single, who had migrated south. The…

  6. Starting Expected Employment Outcomes of Occupational Programs: A Case Study.

    ERIC Educational Resources Information Center

    Passmore, David Lynn; Marron, Michael

    Studying the employment outcomes expected from educational programs at the National Technical Institute for the Deaf (NTID) can aid planners of other occupational programs. The main barriers to planning education for work are the inaccessibility or unavailability of information, the arbitrary nature of occupational classification, and…

  7. Job Values and Early Employment Experiences: A Longitudinal Study.

    ERIC Educational Resources Information Center

    Jepsen, David A.; Noeth, Richard J.

    A study was conducted to examine the predictive relationship between job values and early employment satisfaction and success as well as to provide information about the stability of job values over time. (Job values refer to generalized concepts of desirable future outcomes anticipated from jobs and describe qualities of satisfactions desired as…

  8. Cellular internalization and intracellular biotransformation of silver nanoparticles in Chlamydomonas reinhardtii.

    PubMed

    Wang, Songshan; Lv, Jitao; Ma, Jingyuan; Zhang, Shuzhen

    2016-10-01

    It is necessary to elucidate cellular internalization and intracellular biotransformation in order to accurately assess the toxicity and fate of nanoparticles after interaction with organisms. Therefore, this work employed a combination of high resolution imaging and in situ detection spectroscopic techniques to systematically investigate the intracellular localization, morphology and chemical speciation of silver in the cells of Chlamydomonas reinhardtii, a unicellular freshwater green alga, after exposure to AgNPs coated with polyvinylpyrrolidone at a concentration of 2.0 mg/L. High resolution secondary ion mass spectrometry and high-angle annular dark field scanning transmission electron microscopy together with energy dispersive spectroscopy and selected area electron diffraction collectively confirmed that after 48 h of exposure, AgNPs entered the periplasmic space after cellular internalization into the algal cells. Silver was also found to coexist with sulfur inside the cytoplasm in both crystalline and amorphous forms, which were further identified as β-Ag2S and silver thiolates with synchrotron X-ray absorption spectroscopy. In combination, these analyses demonstrated that silver inside algae could be attributed to the uptake and sequestration of Ag(+) ion released from AgNPs, which was further sequestrated into cellular compartments. This study provides solid evidence for particle internalization and biotransformation of AgNPs after interaction with algae.

  9. Biotransformation of fluticasone: in vitro characterization.

    PubMed

    Pearce, Robin E; Leeder, J Steven; Kearns, Gregory L

    2006-06-01

    Fluticasone propionate (FTP) is a synthetic trifluorinated glucocorticoid with potent anti-inflammatory action that is commonly used in patients with asthma. After oral or intranasal administration, FTP undergoes rapid hepatic biotransformation; the principal metabolite formed is a 17beta-carboxylic acid derivative (M1). M1 formation has been attributed largely to cytochrome P450 3A4 (CYP3A4); however, there are no published data that confirm this assertion. Hence, in vitro studies were conducted to determine the role that human P450s play in the metabolism of FTP. Consistent with in vivo data, human liver microsomes catalyzed the formation of a single metabolite (M1) at substrate concentrations 0.95) with CYP3A4/5 activities in a panel of human liver microsomes (n = 14) and was markedly impaired by the CYP3A inhibitor ketoconazole (>94%) but not by inhibitors of other P450 enzymes (Studies with a panel of cDNA-expressed enzymes revealed that M1 formation was catalyzed primarily by CYP3A enzymes at FTP concentrations biotransformation of FTP to M1 is mediated predominantly by CYP3A enzymes in the liver.

  10. Biocatalysis and biotransformation in Brazil: An overview.

    PubMed

    Birolli, Willian G; Ferreira, Irlon M; Alvarenga, Natália; Santos, Darlisson de A; de Matos, Iara L; Comasseto, João V; Porto, André L M

    2015-01-01

    This review presents the recent research in biocatalysis and biotransformation in Brazil. Several substrates were biotransformed by fungi, bacteria and plants. Biocatalytic deracemization of secondary alcohols, oxidation of sulfides, sp(3) CH hydroxylation and epoxidation of alkenes were described. Chemo-enzymatic resolution of racemic alcohols and amines were carried out with lipases using several substrates containing heteroatoms such as silicon, boron, selenium and tellurium. Biotransformation of nitriles by marine fungi, hydrolysis of epoxides by microorganisms of Brazilian origin and biooxidation of natural products were described. Enzymatic reactions under microwave irradiation, continuous flow, and enzymatic assays using fluorescent probes were reported. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. A new agent developed by biotransformation of polyphyllin VII inhibits chemoresistance in breast cancer

    PubMed Central

    Zhang, Liang; Mao, Ai-Qin; Wei, Juan; Liu, De-Quan; Shi, Gui-Yang; Ma, Xin

    2016-01-01

    Biotransformation by the endophytes of certain plants changes various compounds, and this ‘green’ chemistry becomes increasingly important for finding new products with pharmacological activity. In this study, polyphyllin VII (PPL7) was biotransformed by endophytes from the medicinal plant Paris polyphylla Smith, var. yunnanensis. This produced a new compound, ZH-2, with pharmacological activity in vitro and in vivo. ZH-2 was more potent than PPL7 in selectively killing more chemoresistant than chemosensitive breast cancer cells. ZH-2 also re-sensitized chemoresistant breast cancer cells, as evidenced by the improved anti-cancer activity of commonly-used chemotherapeutic agent in vitro, in vivo, and in clinical samples. This anti-chemoresistance effect of ZH-2 was associated with inhibiting the epithelial-mesenchymal transition (EMT) pathway. Taken together, our findings are the first one to link biotransformation with a biomedicine. The results provide insights into developing new pharmacologically-active agents via biotransformation by endophytes. PMID:26701723

  12. Female employment and fertility: a study based on Chilean data.

    PubMed

    Peek, P

    1975-01-01

    Conflicting studies bring into question the hypothesis that increased employment opportunities for women in the modern sector would reduce the population growth rate. To help clarify the situation, data from about 4000 families in central Chile, obtained from interviews in 1965, are used to test 3 hypotheses: 1) that in the traditional sector of the economy, young children do not adversely affect the mother's labor force participation; 2) that in the modern sector, child care reduces labor force participation unless there are relatives or older children to look after the young children; and 3) that young children also have a positive influence on female employment in that they increase the need for added income. This would be particularly true in the traditional sector where average household income is lower. All hypotheses were proved true by the data. Furthermore, the positive effect on the mother's employment of a larger family size proved to be true in the modern sector as well as the traditional sector. The study indicates that if a country's objective is to lower the population growth rate, a population planning program relying on higher rates of fe male employment will have to be accompanied by other socioeconomic policies intended to achieve a higher level of economic development.

  13. Mathematical modeling of glycerol biotransformation

    NASA Astrophysics Data System (ADS)

    Popova-Krumova, Petya; Yankova, Sofia; Ilieva, Biliana

    2013-12-01

    A method for mathematical modeling of glycerol biotransformation by Klebsiella oxytoca is presented. Glycerol is a renewable resource for it is formed as a by-product during biodiesel production. Because of its large volume production, it seems to be a good idea to develop a technology that converts this waste into products of high value (1, 3-Propanediol; 2, 3-Butanediol). The kinetic model of this process consists of many equations and parameters. The minimization of the least square function will be used for model parameters identification. In cases of parameters identification in multiparameter models the minimization of the least square function is very difficult because it is multiextremal. This is the main problem in the multiextremal function minimization which will be solved on the base a hierarchical approach, using a polynomial approximation of the experimental data.

  14. Structural Interactions of Curcumin Biotransformed Molecules with the N-Terminal Residues of Cytotoxic-Associated Gene A Protein Provide Insights into Suppression of Oncogenic Activities.

    PubMed

    Srivastava, Akhileshwar Kumar; Singh, Divya; Roy, Bijoy Krishna

    2017-03-01

    Curcumin as a natural product has drawn considerable attention in recent years for its multiple pharmacological activities against various diseases, but more studies are required to understand the curcumin pharmacological action considering its low bioavailability. Though numerous reasons contribute to the low bioavailability of curcumin, one of the important reasons is associated with biotransformation of curcumin through either conjugation or reduction depending on curcumin administration route. The orally administered curcumin (CUR) is metabolised into curcumin glucuronidase (CUR-GLR) and curcumin sulphate by conjugation, whereas dihydroxycurcumin, tetrahydrocurcumin, and hexahydrocurcumin (HHC) are formed by reduction after intraperitoneal administration of curcumin. The main aim of the current study was to investigate the pharmacological properties of curcumin and its biotransformed molecules and its inhibitory potential against CagA (cytotoxic-associated gene A) oncoprotein of Helicobacter pylori. All lead molecules followed the Lipinski's five rules for biological activities, except CUR-GLR, whereas druglikeness scores were obtained for all molecules. Subsequently, molecular docking was employed to analyse the binding affinity of molecules with CagA. The docking studies revealed that CUR-GLR has highest binding affinity with CagA, whereas less interactive affinity was observed in HHC. From the virtual screening and docking studies, the current study suggests that the biotransformation of curcumin through conjugation has more potential for inhibition of oncogenic activities of CagA+ H. pylori than reduction.

  15. In vitro biotransformation rates in fish liver S9: effect of dosing techniques.

    PubMed

    Lee, Yung-Shan; Lee, Danny H Y; Delafoulhouze, Maximilien; Otton, S Victoria; Moore, Margo M; Kennedy, Chris J; Gobas, Frank A P C

    2014-08-01

    In vitro biotransformation assays are currently being explored to improve estimates of bioconcentration factors of potentially bioaccumulative organic chemicals in fish. The present study compares thin-film and solvent-delivery dosing techniques as well as single versus multiple chemical dosing for measuring biotransformation rates of selected polycyclic aromatic hydrocarbons in rainbow trout (Oncorhynchus mykiss) liver S9. The findings show that biotransformation rates of very hydrophobic substances can be accurately measured in thin-film sorbent-dosing assays from concentration-time profiles in the incubation medium but not from those in the sorbent phase because of low chemical film-to-incubation-medium mass-transfer rates at the incubation temperature of 13.5 °C required for trout liver assays. Biotransformation rates determined by thin-film dosing were greater than those determined by solvent-delivery dosing for chrysene (octanol-water partition coefficient [KOW ] =10(5.60) ) and benzo[a]pyrene (KOW  =10(6.04) ), whereas there were no statistical differences in pyrene (KOW  =10(5.18) ) biotransformation rates between the 2 methods. In sorbent delivery-based assays, simultaneous multiple-chemical dosing produced biotransformation rates that were not statistically different from those measured in single-chemical dosing experiments for pyrene and benzo[a]pyrene but not for chrysene. In solvent-delivery experiments, multiple-chemical dosing produced biotransformation rates that were much smaller than those in single-chemical dosing experiments for all test chemicals. While thin-film sorbent-phase and solvent delivery-based dosing methods are both suitable methods for measuring biotransformation rates of substances of intermediate hydrophobicity, thin-film sorbent-phase dosing may be more suitable for superhydrophobic chemicals. © 2014 SETAC.

  16. Energy metabolism and biotransformation as endpoints to pre-screen hepatotoxicity using a liver spheroid model

    SciTech Connect

    Xu Jinsheng . E-mail: jinsheng.xu@uwe.ac.uk; Purcell, Wendy M.

    2006-10-15

    The current study investigated liver spheroid culture as an in vitro model to evaluate the endpoints relevant to the status of energy metabolism and biotransformation after exposure to test toxicants. Mature rat liver spheroids were exposed to diclofenac, galactosamine, isoniazid, paracetamol, m-dinitrobenzene (m-DNB) and 3-nitroaniline (3-NA) for 24 h. Pyruvate uptake, galactose biotransformation, lactate release and glucose secretion were evaluated after exposure. The results showed that pyruvate uptake and lactate release by mature liver spheroids in culture were maintained at a relatively stable level. These endpoints, together with glucose secretion and galactose biotransformation, were related to and could reflect the status of energy metabolism and biotransformation in hepatocytes. After exposure, all of the test agents significantly reduced glucose secretion, which was shown to be the most sensitive endpoint of those evaluated. Diclofenac, isoniazid, paracetamol and galactosamine reduced lactate release (P < 0.01), but m-DNB increased lactate release (P < 0.01). Diclofenac, isoniazid and paracetamol also reduced pyruvate uptake (P < 0.01), while galactosamine had little discernible effect. Diclofenac, galactosamine, paracetamol and m-DNB also reduced galactose biotransformation (P < 0.01), by contrast, isoniazid did not. The metabolite of m-DNB, 3-NA, which served as a negative control, did not cause significant changes in lactate release, pyruvate uptake or galactose biotransformation. It is concluded that pyruvate uptake, galactose biotransformation, lactate release and glucose secretion can be used as endpoints for evaluating the status of energy metabolism and biotransformation after exposure to test agents using the liver spheroid model to pre-screen hepatotoxicity.

  17. Fast Food Jobs. National Study of Fast Food Employment.

    ERIC Educational Resources Information Center

    Charner, Ivan; Fraser, Bryna Shore

    A study examined employment in the fast-food industry. The national survey collected data from employees at 279 fast-food restaurants from seven companies. Female employees outnumbered males by two to one. The ages of those fast-food employees in the survey sample ranged from 14 to 71, with fully 70 percent being in the 16- to 20-year-old age…

  18. Screening study of lead compounds for natural product-based fungicides: antifungal activity and biotransformation of 6alpha,7alpha-dihydroxy-beta-himachalene by Botrytis cinerea.

    PubMed

    Daoubi, Mourad; Hernández-Galán, Rosario; Benharref, Ahmed; Collado, Isidro G

    2005-08-24

    Eleven beta-himachalene derivatives were tested, using the poisoning food technique, for their potential antifungal activity against the phytopathogen Botrytis cinerea. Compounds 1-11 displayed moderate activity, whereas the 6,7-diol derivative (12) produced an inhibition of 91% after 6 days. The microbial transformation of 12 was investigated and yielded four new compounds hydroxylated at positions C-5 (13), C-2 (14), C-4 (15), and C-12 (16). The structures were established on the basis of their spectroscopic data including two-dimensional NMR analysis (HMQC, HMBC, nOesy) and nOes. The results obtained from biotransformation experiments shed further light on the detoxification mechanism of the phytopathogenic fungus against this compound and give an indication of the structural modifications that may be necessary if substrates of this type are to be further developed as selective fungal control agents for B. cinerea.

  19. A Monte Carlo simulation method for assessing biotransformation effects on groundwater fuel hydrocarbon plume lengths

    NASA Astrophysics Data System (ADS)

    McNab, Walt W.

    2001-02-01

    Biotransformation of dissolved groundwater hydrocarbon plumes emanating from leaking underground fuel tanks should, in principle, result in plume length stabilization over relatively short distances, thus diminishing the environmental risk. However, because the behavior of hydrocarbon plumes is usually poorly constrained at most leaking underground fuel tank sites in terms of release history, groundwater velocity, dispersion, as well as the biotransformation rate, demonstrating such a limitation in plume length is problematic. Biotransformation signatures in the aquifer geochemistry, most notably elevated bicarbonate, may offer a means of constraining the relationship between plume length and the mean biotransformation rate. In this study, modeled plume lengths and spatial bicarbonate differences among a population of synthetic hydrocarbon plumes, generated through Monte Carlo simulation of an analytical solute transport model, are compared to field observations from six underground storage tank (UST) sites at military bases in California. Simulation results indicate that the relationship between plume length and the distribution of bicarbonate is best explained by biotransformation rates that are consistent with ranges commonly reported in the literature. This finding suggests that bicarbonate can indeed provide an independent means for evaluating limitations in hydrocarbon plume length resulting from biotransformation.

  20. Induction of biotransformation in the liver of Eel (Anguilla anguilla L. ) by sublethal exposure to dinitro-o-cresol: An ultrastructural and biochemical study

    SciTech Connect

    Braunbeck, T.; Voelkl, A. )

    1991-04-01

    Structural and functional alterations in hepatocytes of the European eel, Anguilla anguilla, following a 4-week-exposure to 5, 50, and 250 micrograms/liter dinitro-o-cresol (DNOC) were investigated by means of electron microscopy and biochemistry and compared to liver pathology in eels exposed to the chemical spill into the Rhine river at Basle in November 1986. Whereas phenological parameters (growth, condition factor) are unaffected, ultrastructural and biochemical alterations are detectable at greater than or equal to 50 and 5 micrograms/liter DNOC, respectively. Structural modifications include: rounding-up of the nuclei; fractionation and reduction of the rough endoplasmic reticulum; proliferation of the smooth endoplasmic reticulum (SER), mitochondria, peroxisomes, and lysosomes; bundles of rod-shaped SER profiles; annulate lamellae; membrane whorls within mitochondria; crystallization of the peroxisomal matrix and glycogen bodies; glycogen depletion and lipid augmentation. Structural changes can be correlated to an increase in hepatic lipid and protein contents as well as stimulation of mitochondrial (cytochrome c oxidase), peroxisomal (catalase, allantoinase, uricase), lysosomal (arylsulfatase), and microsomal (esterase) enzymes. An increase in NADPH-cytochrome c reductase and cytochrome P450 as well as UDP-glucuronyltransferase and arylsulfotransferase activities in the microsomal fraction document an induction of hepatic biotransformation as a functional correlate to SER proliferation. Maximum inducibility of biotransformation enzymes at 50 micrograms/liter indicates a biphasic, concentration-dependent reaction of eel liver. Comparison of DNOC-induced effects with liver pathology in eel exposed to the chemical spill in 1986 reveals striking similarities so that DNOC may not be excluded as a possible factor in the fish kill in the Rhine river.

  1. Financial and employment impacts of serious injury: a qualitative study.

    PubMed

    Gabbe, Belinda J; Sleney, Jude S; Gosling, Cameron M; Wilson, Krystle; Sutherland, Ann; Hart, Melissa; Watterson, Dina; Christie, Nicola

    2014-09-01

    To explore the financial and employment impacts following serious injury. Semi-structured telephone administered qualitative interviews with purposive sampling and thematic qualitative analysis. 118 patients (18-81 years) registered by the Victorian State Trauma Registry or Victorian Orthopaedic Trauma Outcomes Registry 12-24 months post-injury. Key findings of the study were that although out-of-pocket treatment costs were generally low, financial hardship was prevalent after hospitalisation for serious injury, and was predominantly experienced by working age patients due to prolonged absences from paid employment. Where participants were financially pressured prior to injury, injury further exacerbated these financial concerns. Reliance on savings and loans and the need to budget carefully to limit financial burden were discussed. Financial implications of loss of income were generally less for those covered by compensation schemes, with non-compensable participants requiring welfare payments due to an inability to earn an income. Most participants reported that the injury had a negative impact on work. Loss of earnings payments from injury compensation schemes and income protection policies, supportive employers, and return to work programs were perceived as key factors in reducing the financial burden of injured participants. Employer-related barriers to return to work included the employer not listening to the needs of the injured participant, not understanding their physical limitations, and placing unrealistic expectations on the injured person. While the financial benefits of compensation schemes were acknowledged, issues accessing entitlements and delays in receiving benefits were commonly reported by participants, suggesting that improvements in scheme processes could have substantial benefits for injured patients. Seriously injured patients commonly experienced substantial financial and work-related impacts of injury. Participants of working age who were

  2. Anaerobic biotransformation of organoarsenical pesticides monomethylarsonic acid and dimethylarsinic acid

    USGS Publications Warehouse

    Sierra-Alvarez, R.; Yenal, U.; Feld, J.A.; Kopplin, M.; Gandolfi, A.J.; Garbarino, J.R.

    2006-01-01

    Monomethylarsonic acid (MMAV) and dimethylarsinic acid (DMAV) are extensively utilized as pesticides, introducing large quantities of arsenic into the environment. Once released into the environment, these organoarsenicals are subject to microbial reactions. Aerobic biodegradation of MMAV and DMAV has been evaluated, but little is known about their fate in anaerobic environments. The objective of this study was to evaluate the biotransformation of MMAV and DMAV in anaerobic sludge. Biologically mediated conversion occurred under methanogenic or sulfate-reducing conditions but not in the presence of nitrate. Monomethylarsonous acid (MMAIII) was consistently observed as an important metabolite of MMAV degradation, and it was recovered in molar yields ranging from 5 to 47%. The main biotransformation product identified from DMAV metabolism was MMAV, which was recovered in molar yields ranging from 8 to 65%. The metabolites indicate that reduction and demethylation are important steps in the anaerobic bioconversion of MMAV and DMAV, respectively. ?? 2006 American Chemical Society.

  3. Biotransformation effects on anti lipogenic activity of citrus extracts.

    PubMed

    Nakajima, Vânia Mayumi; Madeira, José Valdo; Macedo, Gabriela Alves; Macedo, Juliana Alves

    2016-04-15

    Citrus peel is a good source of flavonoids, with higher content in relation to pulp. This study proposed to investigate the anti-lipogenic potential of a newly developed citrus flavonoids extract, obtained from citrus industrial residue, bioprocessed in order to generate a commercial source of some flavonoids naturally found in low quantity. The results showed that the citrus peel extract obtained after biotransformation was a good source of hesperitin and naringenin, flavonoids that has no source for production on a large scale, as in supplements or medicines. Still, the results showed that all extracts could be used in obesity treatment. The original extract, "In Natura", would be useful to reduce new adipocytes synthesis and lipid accumulation, and the extract bioprocessed, "Biotransformed" extract could be used to induce lipolysis on fat tissue.

  4. Application of biotransformation in flavor and fragrance industry.

    PubMed

    Kashi, Fereshteh Jookar; Fooladi, Jamshid; Bayat, Mansour

    2007-05-15

    The present study describes the isolation of microorganisms capable of producing alpha-pinene from beta-pinene. 24 (15 fungi, 9 bacteria) microorganisms were isolated from galbanum, gum and soil, were screened for their ability to transform beta-pinene to alpha-pinene. Biotransformation products were extracted with n-hexan and analyzed by gas chromatography. One microorganism (bacterial strain) were found. The biotransformation medium involved, phosphate buffer pH 6, 100 microL beta-pinene, 1 g biomass of microorganism, 37 degrees C, 150 rpm and 22 h. The experiments were performed in conical flasks. The optimum cell growth were obtained when 30 g L(-1) glycerin applied. The optimum conversion beta-pinene to alpha-pinene was obtained when 20 g L(-1) glycerin applied as carbon source for bacterial strain.

  5. Impact of mothers’ employment on infant feeding and care: a qualitative study of the experiences of mothers employed through the Mahatma Gandhi National Rural Employment Guarantee Act

    PubMed Central

    Nair, Manisha; Ariana, Proochista; Webster, Premila

    2014-01-01

    Objective To explore the experiences of mothers employed through the Mahatma Gandhi National Rural Employment Guarantee Act (MGNREGA) using focus group discussions (FGDs) to understand the impact of mothers’ employment on infant feeding and care. The effects of mothers’ employment on nutritional status of children could be variable. It could lead to increased household income, but could also compromise child care and feeding. Setting The study was undertaken in the Dungarpur district of Rajasthan, India. Participants Mothers of infants <12 months of age. Ten FGDs, two in each of the five administrative blocks of the study district were conducted. The groups were composed of a minimum of 5 and maximum of 8 participants, giving a total of 62 mothers. Thematic analysis was conducted to assess patterns and generate emergent themes. Results Four major themes were identified—‘mothers' employment compromises infant feeding and care’, ‘caregivers’ inability to substitute mothers’ care’, ‘compromises related to childcare and feeding outweigh benefits from MGNREGA’ and ‘employment as disempowering’. Mothers felt that the comprises to infant care and feeding due to long hours of work, lack of alternative adequate care arrangements, low wages and delayed payments outweighed the benefits from the scheme. Conclusions This study provides an account of the trade-off between mothers’ employment and child care. It provides an understanding of the household power relationships, societal and cultural factors that modulate the effects of mothers’ employment. From the perspective of mothers, it helps to understand the benefits and problems related to providing employment to women with infants in the MGNREGA scheme and make a case to pursue policy changes to improve their working conditions. PMID:24694624

  6. Impact of mothers' employment on infant feeding and care: a qualitative study of the experiences of mothers employed through the Mahatma Gandhi National Rural Employment Guarantee Act.

    PubMed

    Nair, Manisha; Ariana, Proochista; Webster, Premila

    2014-04-02

    To explore the experiences of mothers employed through the Mahatma Gandhi National Rural Employment Guarantee Act (MGNREGA) using focus group discussions (FGDs) to understand the impact of mothers' employment on infant feeding and care. The effects of mothers' employment on nutritional status of children could be variable. It could lead to increased household income, but could also compromise child care and feeding. The study was undertaken in the Dungarpur district of Rajasthan, India. Mothers of infants <12 months of age. Ten FGDs, two in each of the five administrative blocks of the study district were conducted. The groups were composed of a minimum of 5 and maximum of 8 participants, giving a total of 62 mothers. Thematic analysis was conducted to assess patterns and generate emergent themes. Four major themes were identified-'mothers' employment compromises infant feeding and care', 'caregivers' inability to substitute mothers' care', 'compromises related to childcare and feeding outweigh benefits from MGNREGA' and 'employment as disempowering'. Mothers felt that the comprises to infant care and feeding due to long hours of work, lack of alternative adequate care arrangements, low wages and delayed payments outweighed the benefits from the scheme. This study provides an account of the trade-off between mothers' employment and child care. It provides an understanding of the household power relationships, societal and cultural factors that modulate the effects of mothers' employment. From the perspective of mothers, it helps to understand the benefits and problems related to providing employment to women with infants in the MGNREGA scheme and make a case to pursue policy changes to improve their working conditions.

  7. Biotransformation of coal derived humic acids by Basidiomycetes

    NASA Astrophysics Data System (ADS)

    Klein, O. I.; Kulikova, N. A.; Stepanova, E. V.; Koroleva, O. V.

    2009-04-01

    Introduction Low energetic coals and wastes of coal industry are promising sources for biologically active compounds including humic acids (HA). Aside from evident advantages of biocatalytic approaches for coal slime conversion such as environmental safety and cost efficiency they also could be used for the improving of HAs biological activity [1, 2]. The aim of the present study was to provide molecular characterization of the HAs formed during biotransformation of coal slime by Basidiomycetes under different cultivation conditions. Materials and methods Biotransformation of brown coal from Solncevskoe deposit (Sakhalin, Russia) was performed by liquid surface cultivation of pure culture Coriolus hirsutus 075 (Wulf. Ex. Fr.) Quel. with rich (contained glucose as a carbon source) and poor (without readily available carbon source) nutrition medium. After 30 days of cultivation coal HAs were separated by alkaline extraction followed by dialysis desalting and drying at 50C. HAs derived were characterized using size-exclusion chromatography, Fourier transformed infrared (FTIR) and 13C NMR spectroscopy. Results and discussion Molecular weight distribution of HA was not significantly affected by Basidiomycetes under all cultivation conditions studied in comparison to HAs extracted from non-conversed coal. FTIR spectra of HA obtained were typical for HAs. Biotransformation of coal did not result in appearance of new functional groups. The exception was observed under rich media conditions where absorbance at 1700 cm-1 was determined related to carbonyl groups of carboxyl and ketonic fragments. Therefore, the revealed phenomena could be explained with additional formation of the above carbonyl groups in the course of biotransformation process. Quantification of 13C NMR spectra revealed decrease of aromatic structures in HA extracted from coal after biotransformation under poor media conditions. Also a significant increase in carboxylic fragments content was observed. So

  8. Biotransformation of phosphogypsum in wastewaters from the dairy industry.

    PubMed

    Wolicka, Dorota

    2008-09-01

    The biotransformation of phosphogypsum by stationary cultures of sulphate reducing bacteria (SRB) in dairy wastewaters (sterile and non-sterile) enriched in phosphogypsum, was studied SRB were isolated from soil contaminated with petroleum-derived products and from wastewaters from the petroleum-refining industry, taking into account that these environments are characteristic for the bacteria of the studied group. The biotransformation products formed were investigated using biological and mineralogical methods. Sulphides in the cultures were determined using the iodometric method, sulphates with the hot barium method, COD by the dichromate method. Determinations involving post-culture sediments and fluids, Ca, S, Sr and P were made using the following analytical procedures: IPC emission spectrometry with induced excitation in the medium and X-ray. Analysis of post-culture sediments was made using a DRON-2 X-ray diffractometer. Eleven communities of microorganisms with varying degrees of effectiveness were obtained, biodegrading 58% to 98% of the organic contaminants in non-sterile wastewater, with simultaneous biotransformation of about 2.5 g phosphogypsum/L.

  9. Biotransformation of acyclovir by an enriched nitrifying culture.

    PubMed

    Xu, Yifeng; Yuan, Zhiguo; Ni, Bing-Jie

    2017-03-01

    This work evaluates the biodegradation of the antiviral drug acyclovir by an enriched nitrifying culture during ammonia oxidation and without the addition of ammonium. The study on kinetics was accompanied with the structural elucidation of biotransformation products through batch biodegradation experiments at two different initial levels of acyclovir (15 mg L(-1) and 15 μg L(-1)). The pseudo first order kinetic studies of acyclovir in the presence of ammonium indicated the higher degradation rates under higher ammonia oxidation rates than those constant degradation rates in the absence of ammonium. The positive correlation was found between acyclovir degradation rate and ammonia oxidation rate, confirming the cometabolism of acyclovir by the enriched nitrifying culture in the presence of ammonium. Formation of the product carboxy-acyclovir (P239) indicated the main biotransformation pathway was aerobic oxidation of the terminal hydroxyl group, which was independent on the metabolic type (i.e. cometabolism or metabolism). This enzyme-linked reaction might be catalyzed by monooxygenase from ammonia oxidizing bacteria or heterotrophs. The formation of carboxy-acyclovir was demonstrated to be irrelevant to the acyclovir concentrations applied, indicating the revealed biotransformation pathway might be the dominant removal pathway of acyclovir in wastewater treatment.

  10. Biotransformation of 1,3-propanediol cyclic sulfate and its derivatives to diols by toluene-permeabilized cells of Bacillus sp. CCZU11-1.

    PubMed

    He, Yu-Cai; Liu, Feng; Zhang, Dan-Ping; Gao, Shan; Li, Zhi-Qing; Tao, Zhi-Cheng; Ma, Cui-Luan

    2015-03-01

    In this study, it was the first report that Bacillus sp. CCZU11-1 was used for the biotransformation of 1,3-propanediol cyclic sulfate (1,3-PDS) and its derivatives. The catalytic performance of Bacillus sp. sulfatase in the biotransformation of 1,3-PDS was significantly improved by biocatalyst permeabilization and immobilization. Using cell permeabilization, the hydrolytic activity of the whole-cell biocatalyst was increased by 3.5-fold after 1.5 h of pretreatment with 10 % (v/v) toluene at 30 °C and pH 7.0. Biotransformation of 20 mM 1,3-PDS for 24 h, 1,3-propanediol (1,3-PD) could be obtained in the yield of 97.4 % under the optimized reaction condition. Additionally, the immobilized biocatalysts, permeabilized cells entrapped in calcium alginate, and cross-linked enzyme aggregates were further employed to biotansform 1,3-PDS. Moreover, the total operational time of the immobilized biocatalysts could reach above 240 h with high conversion rate (>90 %).

  11. Long term in vivo biotransformation of iron oxide nanoparticles.

    PubMed

    Levy, Michael; Luciani, Nathalie; Alloyeau, Damien; Elgrabli, Dan; Deveaux, Vanessa; Pechoux, Christine; Chat, Sophie; Wang, Guillaume; Vats, Nidhi; Gendron, François; Factor, Cécile; Lotersztajn, Sophie; Luciani, Alain; Wilhelm, Claire; Gazeau, Florence

    2011-06-01

    The long term outcome of nanoparticles in the organism is one of the most important concerns raised by the development of nanotechnology and nanomedicine. Little is known on the way taken by cells to process and degrade nanoparticles over time. In this context, iron oxide superparamagnetic nanoparticles benefit from a privileged status, because they show a very good tolerance profile, allowing their clinical use for MRI diagnosis. It is generally assumed that the specialized metabolism which regulates iron in the organism can also handle iron oxide nanoparticles. However the biotransformation of iron oxide nanoparticles is still not elucidated. Here we propose a multiscale approach to study the fate of nanomagnets in the organism. Ferromagnetic resonance and SQUID magnetization measurements are used to quantify iron oxide nanoparticles and follow the evolution of their magnetic properties. A nanoscale structural analysis by electron microscopy complements the magnetic follow-up of nanoparticles injected to mice. We evidence the biotransformation of superparamagnetic maghemite nanoparticles into poorly-magnetic iron species probably stored into ferritin proteins over a period of three months. A putative mechanism is proposed for the biotransformation of iron-oxide nanoparticles. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Biotransformation potential of phytosterols under anoxic and anaerobic conditions.

    PubMed

    Dykstra, C M; Giles, H D; Banerjee, S; Pavlostathis, S G

    2014-01-01

    The biotransformation potential of three phytosterols (campesterol, stigmasterol and β-sitosterol) under denitrifying, sulfate-reducing and fermentative/methanogenic conditions was assessed. Using a group contribution method, the standard Gibbs free energy of phytosterols was calculated and used to perform theoretical energetic calculations. The oxidation of phytosterols under aerobic, nitrate-reducing, sulfate-reducing and methanogenic conditions was determined to be energetically feasible. However, using semi-continuously fed cultures maintained at 20-22 °C over 16 weekly feeding cycles (112 days; retention time, 21 days), phytosterol removal was observed under nitrate-reducing and sulfate-reducing conditions, but not under fermentative/methanogenic conditions. Under sulfate-reducing conditions, stigmast-4-en-3-one was identified as an intermediate of phytosterol biotransformation, a reaction more likely carried out by dehydrogenases/isomerases, previously reported to act on cholesterol under both oxic and anoxic (denitrifying) conditions. Further study of the biotransformation of phytosterols under anoxic/anaerobic conditions is necessary to delineate the factors and conditions leading to enhanced phytosterol biodegradation and the development of effective biological treatment systems for the removal of phytosterols from pulp and paper wastewaters and other phytosterol-bearing waste streams.

  13. Biotransformation of testosterone and testosterone heptanoate by four filamentous fungi.

    PubMed

    Ghasemi, Sabrieh; Mohajeri, Maryam; Habibi, Zohreh

    2014-12-01

    The microbial transformations of testosterone and testosterone heptanoate by four fungi: Absidia griseolla var. igachii PTCC 5260, Acremonium chrysogenu PTCC 5271, Fusarium fujikuroi PTCC 5144, and Fusarium solani complex PTCC 5285 were investigated for the first time. Incubation of testosterone heptanoate with F. fujikuroi and F. solani yielded three metabolites, which were isolated and characterized as testosterone, androst-4-ene-3,17-dione, and 6β-hydroxy testosterone. 6β-Hydroxy testosterone was the major metabolite obtained from testosterone heptanoate biotransformation by two fungal species. A. griseolla and A. chrysogenu produced 14α-hydroxy testosterone as major metabolite, together with testosterone and 6β-hydroxy testosterone in lower yields. The biotransformation of testosterone by F. fujikuroi and A. griseolla was also investigated in order to examine the influence of the ester group on the course of transformation. Androst-4-ene-3,17-dione was only identified in the biotransformation of testosterone by F. fujikuroi. The same product was observed in incubation of testosterone by A. griseolla, together with 14α-hydroxy testosterone in very low yield. Furthermore, time course study was also carried out in order to examine the formation of metabolites as a function of time, which was determined by HPLC. The structures of compounds were determined by their comprehensive spectroscopic analysis and comparison with literature data.

  14. Refining the Use of Statistics in Employment Studies.

    ERIC Educational Resources Information Center

    Lopez, Randy L.

    1985-01-01

    The statistical methods used by courts and regulatory agencies to analyze data relating to equal employment and affirmative action are reviewed, along with suggested methods for colleges and universities to produce more meaningful Equal Employment Opportunity management documents. (MSE)

  15. Organochlorine compounds in Lake Superior: Chiral polychlorinated biphenyls and biotransformation in the aquatic food web

    USGS Publications Warehouse

    Wong, Charles S.; Mabury, Scott A.; Whittle, D. Michael; Backus, Sean M.; Teixeira, Camilla; DeVault, David S.; Bronte, Charles R.; Muir, Derek C.G.

    2004-01-01

    The enantiomeric composition of seven chiral PCB congeners was measured in the Lake Superior aquatic food web sampled in 1998, to determine the extent of enantioselective biotransformation in aquatic biota. All chiral PCB congeners studied (CBs 91, 95, 136, 149, 174, 176, and 183) biomagnified in the Lake Superior aquatic food web, based on biomagnification and food web magnification factors greater than unity. PCB atropisomers were racemic in phytoplankton and zooplankton, suggesting no biotransformation potential toward PCBs for these low trophic level organisms. However, Diporeia and mysids had significantly nonracemic residues for most chiral congeners studied. This observation suggests that these macrozooplankton can stereoselectively metabolize chiral congeners. Alternatively, macrozooplankton obtained nonracemic residues from feeding on organic-rich suspended particles and sediments, which would imply that stereoselective microbial PCB biotransformation may be occurring in Lake Superior sediments at PCB concentrations far lower than that previously associated with such activity. Widely nonracemic PCB residues in forage fish (lake herring, rainbow smelt, and slimy sculpin) and lake trout suggest a combination of both in vivo biotransformation and uptake of nonracemic residues from prey for these species. Minimum biotransformation rates, calculated from enantiomer mass balances between predators and prey, suggest metabolic half-lives on the order of 8 yr for CB 136 in lake trout and 2.6 yr for CB 95 in sculpins. This result suggests that significant biotransformation may occur for metaboliz able PCB congeners over the lifespan of these biota. This study highlights the potential of chiral analysis to study biotransformation processes in food webs.

  16. Upset susceptibility study employing circuit analysis and digital simulation

    NASA Technical Reports Server (NTRS)

    Carreno, V. A.

    1984-01-01

    This paper describes an approach to predicting the susceptibility of digital systems to signal disturbances. Electrical disturbances on a digital system's input and output lines can be induced by activities and conditions including static electricity, lightning discharge, Electromagnetic Interference (EMI) and Electromagnetic Pulsation (EMP). The electrical signal disturbances employed for the susceptibility study were limited to nondestructive levels, i.e., the system does not sustain partial or total physical damage and reset and/or reload will bring the system to an operational status. The front-end transition from the electrical disturbances to the equivalent digital signals was accomplished by computer-aided circuit analysis. The Super-Sceptre (system for circuit evaluation of transient radiation effects) Program was used. Gate models were developed according to manufacturers' performance specifications and parameters resulting from construction processes characteristic of the technology. Digital simulation at the gate and functional level was employed to determine the impact of the abnormal signals on system performance and to study the propagation characteristics of these signals through the system architecture. Example results are included for an Intel 8080 processor configuration.

  17. Upset susceptibility study employing circuit analysis and digital simulation

    NASA Astrophysics Data System (ADS)

    Carreno, V. A.

    1984-12-01

    An approach to predict the susceptibility of digital systems to signal disturbances is described. Electrical disturbances on a digital system's input and output lines can be induced by activities and conditions including static electricity, lightning discharge, electromagnetic interference (EMI), and electromagnetic pulsation (EMP). The electrical signal disturbances employed for the susceptibility study were limited to nondestructive levels, i.e., the system does not sustain partial or total physical damage and reset and/or reload brings the system to an operational status. The front-end transition from the electrical disturbances to the equivalent digital signals was accomplished by computer-aided circuit analysis. The super-sceptre (system for circuit evaluation of transient radiation effects) programs was used. Gate models were developed according to manufacturers' performance specifications and parameters resulting from construction processes characteristic of the technology. Digital simulation at the gate and functional level was employed to determine the impact of the abnormal signals on system performance and to study the propagation characteristics of these signals through the system architecture. Example results are included for an Intel 8080 processor configuration.

  18. Biotransformation of cis-1,2-dichloroethylene in aquifer material from Picatinny Arsenal, Morris County, New Jersey. Water Resources Investigation

    SciTech Connect

    Ehlke, T.A.; Imbrigiotta, T.E.; Wilson, B.H.; Wilson, J.T.

    1991-01-01

    Soil cores were collected within and adjacent to a trichloroethylen plume that has contaminated the shallow aquifer at Picatinny Arsenal, New Jersey, to study the rate of cis-1,2-dichloroethylene biotransformation. Soil cores also were collected at a highly contaminated site within the plume to determine the effect of different electron donors on the rate of cis-1,2-dichloroetylene biotransformation under methanogenic conditions. Ground-water samples were analyzed for volatile organic compounds to study the relation between volatile-organic-compound concentrations and the biotransformation of cis-1,2-dichloroethylene. Biotransformation in microcosms from sites within the plume ranged from slight to more than 90 percent after an incubation period of 32 weeks. The most extensive biotransformation in soil microcosms occurred at a site near the highest in situ cis-1,2-dichloroethylene concentration measured at the arsenal (710 micrograms per liter). Biotransformation was negligible at an uncontaminated site. Amendment of soil microcosms with combinations of methanol, formate, toluene, p-cresol, propionate, and butyrate inhibited the biotransformation of cis-1,2-dichloroethylene. A combination of methanol and formate had the greatest inhibitory effect.

  19. Application of in Vitro Biotransformation Data and ...

    EPA Pesticide Factsheets

    The adverse biological effects of toxic substances are dependent upon the exposure concentration and the duration of exposure. Pharmacokinetic models can quantitatively relate the external concentration of a toxicant in the environment to the internal dose of the toxicant in the target tissues of an exposed organism. The exposure concentration of a toxic substance is usually not the same as the concentration of the active form of the toxicant that reaches the target tissues following absorption, distribution, and biotransformation of the parent toxicant. Biotransformation modulates the biological activity of chemicals through bioactivation and detoxication pathways. Many toxicants require biotransformation to exert their adverse biological effects. Considerable species differences in biotransformation and other pharmacokinetic processes can make extrapolation of toxicity data from laboratory animals to humans problematic. Additionally, interindividual differences in biotransformation among human populations with diverse genetics and lifestyles can lead to considerable variability in the bioactivation of toxic chemicals. Compartmental pharmacokinetic models of animals and humans are needed to understand the quantitative relationships between chemical exposure and target tissue dose as well as animal to human differences and interindividual differences in human populations. The data-based compartmental pharmacokinetic models widely used in clinical pharmacology ha

  20. Nanoparticles--production and role in biotransformation.

    PubMed

    Mohapatra, D P; Gassara, F; Brar, S K

    2011-02-01

    Renewed interest has arisen in the manufacture of nanoparticles due to their unusually enhanced physico-chemical properties and biological activities compared to the bulk parent materials. The industrial scale production and wide variety of application of nanoparticles has resulted in broad range applications in biotechnology, more recently in the increase in efficiency of biotransformation processes. Biotransformation processes utilized to form different bio-products and nanoparticles demonstrate various roles in the bio-products formation. In order to address the issue, it is necessary to understand the different methods available for synthesis of nanoparticles and their effects on biotransformation process, an efficient process for utilization of nanoparticles. In this review, an overview of physical, chemical and biological methods for synthesis of nanoparticles and their role in biotransformation process on formation of different bio-products, such as bioethanol, biohydrogen, biodiesel, enzymes and bioplastics is outlined. In fact, the nanoparticles are going to prove revolutionary in the field of biotransformation by improving the efficiency and yield and often widening the application range.

  1. Whole cell biotransformation for reductive amination reactions

    PubMed Central

    Klatte, Stephanie; Lorenz, Elisabeth; Wendisch, Volker F

    2014-01-01

    Whole cell biotransformation systems with enzyme cascading increasingly find application in biocatalysis to complement or replace established chemical synthetic routes for production of, e.g., fine chemicals. Recently, we established an Escherichia coli whole cell biotransformation system for reductive amination by coupling a transaminase and an amino acid dehydrogenase with glucose catabolism for cofactor recycling. Transformation of 2-keto-3-methylvalerate to l-isoleucine by E. coli cells was improved by genetic engineering of glucose metabolism for improved cofactor regeneration. Here, we compare this system with different strategies for cofactor regeneration such as cascading with alcohol dehydrogenases, with alternative production hosts such as Pseudomonas species or Corynebacterium glutamicum, and with improving whole cell biotransformation systems by metabolic engineering of NADPH regeneration. PMID:24406456

  2. Whole cell biotransformation for reductive amination reactions.

    PubMed

    Klatte, Stephanie; Lorenz, Elisabeth; Wendisch, Volker F

    2014-01-01

    Whole cell biotransformation systems with enzyme cascading increasingly find application in biocatalysis to complement or replace established chemical synthetic routes for production of, e.g., fine chemicals. Recently, we established an Escherichia coli whole cell biotransformation system for reductive amination by coupling a transaminase and an amino acid dehydrogenase with glucose catabolism for cofactor recycling. Transformation of 2-keto-3-methylvalerate to l-isoleucine by E. coli cells was improved by genetic engineering of glucose metabolism for improved cofactor regeneration. Here, we compare this system with different strategies for cofactor regeneration such as cascading with alcohol dehydrogenases, with alternative production hosts such as Pseudomonas species or Corynebacterium glutamicum, and with improving whole cell biotransformation systems by metabolic engineering of NADPH regeneration.

  3. Influence of biotransformation on trophic transfer of the PAH, fluoranthene.

    PubMed

    Palmqvist, Annemette; Rasmussen, Lene Juel; Forbes, Valery E

    2006-12-01

    intestinal Flu concentrations in N. virens. Our results indicate that accumulation of PAHs by infaunal organisms may play an important role in the transfer of this type of contaminant to higher trophic levels. Moreover, we observed differences in transfer potential between parent compounds and their respective metabolites, which may influence the fate of these compounds in marine ecosystems. However, from the present study it cannot be concluded whether differences in biotransformation ability among prey species can lead to different effects in their predators.

  4. Arsenic biotransformation and volatilization in transgenic rice

    PubMed Central

    Meng, Xiang-Yan; Qin, Jie; Wang, Li-Hong; Duan, Gui-Lan; Sun, Guo-Xin; Wu, Hui-Lan; Chu, Cheng-Cai; Ling, Hong-Qing; Rosen, Barry P.; Zhu, Yong-Guan

    2011-01-01

    Summary Biotransformation of arsenic includes oxidation, reduction, methylation and conversion to more complex organic arsenicals. Members of the class of arsenite [As(III)] S-adenosylmethyltransferase enzymes catalyze As(III) methylation to a variety of mono-, di- and trimethylated species, some of which are less toxic than As(III) itself. However, no methyltransferase gene has been identified in plants. Here, an arsM gene from the soil bacterium Rhodopseudomonas palustris was expressed in Japonica rice (Oryza sativa L.) cultivar Nipponbare, and the transgenic rice produced methylated arsenic species, which were measured by inductively coupled plasma mass spectrometry (ICP-MS) and high performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS). Both monomethylarsenate [MAs(V)] and dimethylarsenate [DMAs(V)] were detected in the root and shoot of transgenic rice. After 12-d exposure to As(III), the transgenic rice gave off 10-fold more volatile arsenicals. The present study demonstrates that expression of an arsM gene in rice induces arsenic methylation and volatilization, providing a potential stratagem for phytoremediation theoretically. PMID:21517874

  5. Pharmacokinetics and biotransformation of tea polyphenols.

    PubMed

    Qiao, Jinping; Kong, Xiangyi; Kong, Aiying; Han, Mei

    2014-01-01

    Tea is an infusion of the leaves of the Camellia sinensis plant and is the most widely consumed beverage in the world after water. The main chemical components in teas are phenolic compounds (tea polyphenols, mainly tea catechins). A large number of in vitro and in vivo scientific studies have supported that the tea polyphenols can provide a number of health benefits such as, reducing the incidence of coronary heart disease, diabetes and cancer. Recently, tea polyphenols have proven highly attractive as lead compounds for drug discovery programs. A clear understanding of chemistry, stability, pharmacokinetics and metabolic fate of tea will be significant to elucidate many medicinal effects by biochemical theory and pharmaceutical development. This article reviews the current literature on the pharmacoknetics and biotransformation of tea catechins. The half-lives of tea polyphenols are 2-4h and their absorption and elimination are rapid in humans. The peak times (tmax) are 1 and 3 h after oral administration and the peak plasma concentrations are low μM range. It has been reported that catechins are easily metabolized by enzyme and microbe, and the main metabolic pathways are methylation, glucuronidation, sulfation, ring-fission metabolism, and so on. The information is important to discuss some of the challenges and benefits of pursuing this family of compounds for drug discovery.

  6. [Effects of Germanium Concentrations on Germanium Accumulation and Biotransformation of Polysaccarified Germanium in Cordyceps militaris].

    PubMed

    Wang, Ju-feng; Li, Hu-ming; Yang, Dao-de

    2015-11-01

    To study the effects of Germanium (Ge) concentration on Ge accumulation and biotransformation of polysaccarified Ge (PG) in Cordyceps militaris. Solid and liquid culture were used in this study. In the solid culture conditions, when the Ge concentration of medium was 200 mg/L, the sporophore biomass of Cordyceps militaris was the maximum; and when Ge concentration was 300 mg/L,the amount of biotransformation of PG in sporophore was the highest; and when the Ge concentration is 250 mg/L, conversion rate of organic germanium (OG) in sporophore reached the highest value. In the liquid culture conditions, when the Ge concentration was 250 mg/L, the mycelium biomass of Cordyceps militaris was the maximum; and when Ge concentration was 150 mg/L, the amount of organic conversion of PG in mycelium was the most; and conversion rate of OG in mycelium was the highest in media with the Ge concentration of 200 mg/L. This study showed the germanium concentrations in 150 - 300 mg/L was more suitable for Ge accumulation and biotransformation of PG in Cordyceps militaris. In general, the biotransformation capacity to germanium of sporophore was stronger than that of mycelium of Cordyceps militaris. Germanium can significantly affect Ge accumulation and biotransformation of PG in Cordyceps militaris (P < 0.05) at different concentration. This result has practical value for Ge enriched cultivation of fruiting body in Cordyceps militaris.

  7. Mechanism of xanthine oxidase catalyzed biotransformation of HMX under anaerobic conditions.

    PubMed

    Bhushan, Bharat; Paquet, Louise; Halasz, Annamaria; Spain, Jim C; Hawari, Jalal

    2003-06-27

    Enzyme catalyzed biotransformation of the energetic chemical octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) is not known. The present study describes a xanthine oxidase (XO) catalyzed biotransformation of HMX to provide insight into the biodegradation pathway of this energetic chemical. The rates of biotransformation under aerobic and anaerobic conditions were 1.6+/-0.2 and 10.5+/-0.9 nmolh(-1)mgprotein(-1), respectively, indicating that anaerobic conditions favored the reaction. The biotransformation rate was about 6-fold higher using NADH as an electron-donor compared to xanthine. During the course of reaction, the products obtained were nitrite (NO(2)(-)), methylenedinitramine (MDNA), 4-nitro-2,4-diazabutanal (NDAB), formaldehyde (HCHO), nitrous oxide (N(2)O), formic acid (HCOOH), and ammonium (NH(4)(+)). The product distribution gave carbon and nitrogen mass-balances of 91% and 88%, respectively. A comparative study with native-, deflavo-, and desulfo-XO and the site-specific inhibition studies showed that HMX biotransformation occurred at the FAD-site of XO. Nitrite stoichiometry revealed that an initial single N-denitration step was sufficient for the spontaneous decomposition of HMX.

  8. Background Study on Employment and Labour Market in Romania.

    ERIC Educational Resources Information Center

    Ciobanu, Adrian; Parciog, Speranta

    Romania's adoption of a more gradual approach in restructuring and privatizing the state-owned sector has resulted in industry with an unchanged structure that remains the main cause of social and economic decline. Employment has shown a steady decline. Industrial employment has decreased dramatically. Sectors like transport, hotels, and…

  9. A Comparative Study of Graduate Employment Surveys: 2003-2011

    ERIC Educational Resources Information Center

    Changjun, Yue

    2014-01-01

    Based on data from nationwide surveys of graduates conducted in 2003, 2005, 2007, 2009, and 2011 by the Institute of Economics of Education, Peking University, this article provides a statistical comparative analysis of employment results and the job search process. It examines the characteristics of college graduate employment in China, as well…

  10. Case Study: Implementing Employment Equity at Carleton University.

    ERIC Educational Resources Information Center

    Farquhar, Robin H.; And Others

    Carleton University (Ontario, Canada) has implemented an employment equity plan and has received a federal merit award for this program. The program has involved a concrete investment of time and resources for training, review of employment systems, implementation and monitoring, and ongoing attention at the senior policy level. At the outset the…

  11. Combining Study and Employment: A Step Too Far?

    ERIC Educational Resources Information Center

    Robotham, David

    2009-01-01

    Purpose: The purpose of this paper is to report the results of a survey of part-time employment among university students. The survey seeks to establish the nature and characteristics of that employment, and to determine the extent to which it is comparable to similar institutions. The research also aims to examine the possible consequences of…

  12. Background Study on Employment and Labour Market in Bulgaria.

    ERIC Educational Resources Information Center

    Beleva, Iskra; Tzanov, Vasil; Noncheva, Teodora; Zareva, Iren

    A factual and descriptive analysis of the employment situation in Bulgaria showed that the transition to a market economy has led to a substantial reduction of employment. The economic restructuring begun in 1990 has proved very difficult, and the privatization of the large industrial enterprises faces problems mainly due to insufficient interest…

  13. Combining Study and Employment: A Step Too Far?

    ERIC Educational Resources Information Center

    Robotham, David

    2009-01-01

    Purpose: The purpose of this paper is to report the results of a survey of part-time employment among university students. The survey seeks to establish the nature and characteristics of that employment, and to determine the extent to which it is comparable to similar institutions. The research also aims to examine the possible consequences of…

  14. Work Ethic and Employment Status: A Study of Jobseekers

    ERIC Educational Resources Information Center

    Hill, Roger B.; Fouts, Susan

    2005-01-01

    Although there have been numerous changes within the workplace during the past century, employers continue to search for employees with a strong work ethic. Employers often cite a strong work ethic as the most desired characteristic in a new employee. Work ethic can be described as a set of characteristics and attitudes in which an individual…

  15. A Study of the Workforce Needs of Maryland Employers.

    ERIC Educational Resources Information Center

    Maryland State Higher Education Commission, Annapolis.

    The Maryland Higher Education Commission surveyed more than 2,500 employers in the state to learn what programs at various degree levels were desired by employers. The results were examined along with labor market data about the projected number of job openings in specific occupational areas. It was concluded that nearly 60 percent of job openings…

  16. Biotransformation of trace organic contaminants in open-water unit process treatment wetlands.

    PubMed

    Jasper, Justin T; Jones, Zackary L; Sharp, Jonathan O; Sedlak, David L

    2014-05-06

    The bottoms of shallow, open-water wetland cells are rapidly colonized by a biomat consisting of an assemblage of photosynthetic and heterotrophic microorganisms. To assess the contribution of biotransformation in this biomat to the overall attenuation of trace organic contaminants, transformation rates of test compounds measured in microcosms were compared with attenuation rates measured in a pilot-scale system. The biomat in the pilot-scale system was composed of diatoms (Staurosira construens) and a bacterial community dominated by β- and γ-Proteobacteria. Biotransformation was the dominant removal mechanism in the pilot-scale system for atenolol, metoprolol, and trimethoprim, while sulfamethoxazole and propranolol were attenuated mainly via photolysis. In microcosm experiments, biotransformation rates increased for metoprolol and propranolol when algal photosynthesis was supported by irradiation with visible light. Biotransformation rates increased for trimethoprim and sulfamethoxazole in the dark, when microbial respiration depleted dissolved oxygen concentrations within the biomat. During summer, atenolol, metoprolol, and propranolol were rapidly attenuated in the pilot-scale system (t1/2 < 0.5 d), trimethoprim and sulfamethoxazole were transformed more slowly (t1/2 ≈ 1.5-2 d), and carbamazepine was recalcitrant. The combination of biotransformation and photolysis resulted in overall transformation rates that were 10 to 100 times faster than those previously measured in vegetated wetlands, allowing for over 90% attenuation of all compounds studied except carbamazepine within an area similar to that typical of existing full-scale vegetated treatment wetlands.

  17. Biotransformation and adsorption of pharmaceutical and personal care products by activated sludge after correcting matrix effects.

    PubMed

    Deng, Yu; Li, Bing; Yu, Ke; Zhang, Tong

    2016-02-15

    This study reported significant suppressive matrix effects in analyses of six pharmaceutical and personal care products (PPCPs) in activated sludge, sterilized activated sludge and untreated sewage by ultra-performance liquid chromatography-tandem mass spectrometry. Quantitative matrix evaluation on selected PPCPs supplemented the limited quantification data of matrix effects on mass spectrometric determination of PPCPs in complex environment samples. The observed matrix effects were chemical-specific and matrix-dependent, with the most pronounced average effect (-55%) was found on sulfadiazine in sterilized activated sludge. After correcting the matrix effects by post-spiking known amount of PPCPs, the removal mechanisms and biotransformation kinetics of selected PPCPs in activated sludge system were revealed by batch experiment. Experimental data elucidated that the removal of target PPCPs in the activated sludge process was mainly by biotransformation while contributions of adsorption, hydrolysis and volatilization could be neglected. High biotransformation efficiency (52%) was observed on diclofenac while other three compounds (sulfadiazine, sulfamethoxazole and roxithromycin) were partially biotransformed by ~40%. The other two compounds, trimethoprim and carbamazepine, showed recalcitrant to biotransformation of the activated sludge.

  18. Pathways of reductive 2,4-dinitroanisole (DNAN) biotransformation in sludge.

    PubMed

    Olivares, Christopher; Liang, Jidong; Abrell, Leif; Sierra-Alvarez, Reyes; Field, Jim A

    2013-06-01

    As the use of the insensitive munition compound 2,4-dinitroanisole (DNAN) increases, releases to the environment may pose a threat to local ecosystems. Little is known about the environmental fate of DNAN and the conversions caused by microbial activity. We studied DNAN biotransformation rates in sludge under aerobic, microaerophilic, and anaerobic conditions, detected biotransformation products, and elucidated their chemical structures. The biotransformation of DNAN was most rapid under anaerobic conditions with H2 as a cosubstrate. The results showed that the ortho nitro group in DNAN is regioselectively reduced to yield 2-methoxy-5-nitroaniline (MENA), and then the para nitro group is reduced to give 2,4-diaminoanisole (DAAN). Both MENA and DAAN were identified as important metabolites in all redox conditions. Azo and hydrazine dimer derivatives formed from the coupling of DNAN reduction products in anaerobic conditions. Secondary pathways included acetylation and methylation of amine moieties, as well as the stepwise O-demethylation and dehydroxylation of methoxy groups. Seven unique metabolites were identified which enabled elucidation of biotransformation pathways. The results taken as a whole suggest that reductive biotransformation is an important fate of DNAN leading to the formation of aromatic amines as well as azo and hydrazine dimeric metabolites. Copyright © 2012 Wiley Periodicals, Inc.

  19. Applications and Mechanisms of Ionic Liquids in Whole-Cell Biotransformation

    PubMed Central

    Fan, Lin-Lin; Li, Hong-Ji; Chen, Qi-He

    2014-01-01

    Ionic liquids (ILs), entirely composed of cations and anions, are liquid solvents at room temperature. They are interesting due to their low vapor pressure, high polarity and thermostability, and also for the possibility to fine-tune their physicochemical properties through modification of the chemical structures of their cations or anions. In recent years, ILs have been widely used in biotechnological fields involving whole-cell biotransformations of biodiesel or biomass, and organic compound synthesis with cells. Research studies in these fields have increased from the past decades and compared to the typical solvents, ILs are the most promising alternative solvents for cell biotransformations. However, there are increasing limitations and new challenges in whole-cell biotransformations with ILs. There is little understanding of the mechanisms of ILs’ interactions with cells, and much remains to be clarified. Further investigations are required to overcome the drawbacks of their applications and to broaden their application spectrum. This work mainly reviews the applications of ILs in whole-cell biotransformations, and the possible mechanisms of ILs in microbial cell biotransformation are proposed and discussed. PMID:25007820

  20. Bioavailability and biotransformation of sediment-associated pyrethroid insecticides in Lumbriculus variegatus.

    PubMed

    You, Jing; Brennan, Amanda; Lydy, Michael J

    2009-06-01

    In the present study, bioaccumulation potential of two pyrethroid insecticides, bifenthrin and permethrin, was measured using a Lumbriculus variegatus sediment bioaccumulation test. Two sediments differing in their physical characteristics and two different aging periods were tested. Desorption rates measured by Tenax extraction suggested that pyrethroids were bioavailable to L. variegatus, however bioavailability varied among chemicals, sediments and aging time, and was greater for permethrin than bifenthrin. The relatively low biota-sediment accumulation factor (BSAF) values resulted from the extensive biotransformation of pyrethroids by L. variegatus. Biotransformation capacity of L. variegatus to permethrin was further studied with a water-only exposure, and the percentage parent compound dropped to 36.0% after 14 d. These results indicated sediment-associated pyrethroids were bioavailable to L. variegatus, however bioaccumulation was limited because L. variegatus was capable of biotransforming the pyrethroids.

  1. Biotransformation of Progesterone by Whole Cells of Filamentous Fungi Aspergillus brasiliensis.

    PubMed

    Hosseinabadi, Tahereh; Vahidi, Hossein; Nickavar, Bahman; Kobarfard, Farzad

    2015-01-01

    Microbial steroid biotransformations have found a wide-reaching application for the production of more precious and functionalized compounds due to their high regio-and stereo selectivity. In this study, the possibility of using filamentous fungi Aspergillus brasiliensiscells in the biotransformation of progesterone, a C-21 steroid hormone was studied for the first time. The fungal strain was inoculated into the transformation medium supplemented with progesterone as a substrate. Biotransformation of this steroid for 7 days afforded 3 different hydroxylated metabolites: 11α-hydroxy progesterone; 14α-hydroxyprogesteroneand21-hydroxyprogesterone. The metabolites were separated by thin layer chromatography. Structure determinations of the metabolites were performed by comparing NMR, MS and IR spectra of the starting compound with those of metabolites. These results may be of industrial importance because the metabolites can be used as precursor of some steroid drugs.

  2. LC/MS/MS identification of glycosides produced by biotransformation of cinnamyl alcohol in Rhodiola rosea compact callus aggregates.

    PubMed

    Tolonen, Ari; György, Zsuzsanna; Jalonen, Jorma; Neubauer, Peter; Hohtola, Anja

    2004-10-01

    Cinnamyl alcohol was added to the media of compact callus aggregates (CCA) of Rhodiola rosea for stimulating the production of cinnamyl glycosides. The biotransformation reaction produced high amounts of rosin, while only a very low amount of rosavin was produced. As the consumption rate of cinnamyl alcohol was much higher than production of rosin, the aqueous methanol extracts of compact callus aggregates were studied by liquid chromatography-mass spectrometric methods and four new unexpected biotransformation products of cinnamyl alcohol were identified.

  3. Embryotoxicity and biotransformation responses in zebrafish exposed to water-soluble fraction of crude oil.

    PubMed

    Pauka, Luciana M; Maceno, Marcell; Rossi, Stefani C; Silva de Assis, Helena C

    2011-04-01

    The toxic effects of water-soluble fraction (WSF) of crude oil (API27, Petrobras Campos Basin, Brazil) were evaluated during the early life stages of zebrafish, as well as its biotransformation in juvenile fish. Embryonic development was studied during 96 h. Reduced heartbeat rate, weak pigmentation, tail defects, and embryo mortality were observed for all of the tested concentrations of the WSF. Activities of the biotransformation enzymes were induced at the highest concentrations, showing that these enzymes played a role in its elimination. As shown in this study the crude oil WSF altered the normal embryonic development of fish.

  4. Biotransformation of phosphogypsum by bacteria isolated from petroleum-refining wastewaters.

    PubMed

    Wolicka, Dorota; Kowalski, Włodzimierz; Boszczyk-Maleszak, Hanka

    2005-01-01

    The biotransformation of phosphogypsum in cultures of sulfate-reducing bacteria (SRB) isolated from crude petroleum-refining wastewaters or purified using activated sludge method was studied. Selection was with the microcosms method on Postgate and minimal medium with different carbon sources, Emerson medium and petroleum-refining wastewaters. Highest hydrogen sulfide production, in excess of 500 mg/L, was observed in culture of microorganisms isolated from purified petroleum-refining wastewaters in Postgate medium with phenol as sole carbon source. 76% phenol reduction with simultaneous biotransformation of 2.7g phosphogypsum/L (1350 mg SO4/L) was obtained. The results regarding post-culture sediment indicated 66% utilization of phosphogypsum introduced into the culture (5 g/L), which reflects the active biotransformation of phosphogypsum by the community selected from the wastewaters.

  5. Phenolic Biotransformations during Conversion of Ferulic Acid to Vanillin by Lactic Acid Bacteria

    PubMed Central

    Kaur, Baljinder; Kumar, Balvir

    2013-01-01

    Vanillin is widely used as food additive and as a masking agent in various pharmaceutical formulations. Ferulic acid is an important precursor of vanillin that is available in abundance in cell walls of cereals like wheat, corn, and rice. Phenolic biotransformations can occur during growth of lactic acid bacteria (LAB), and their production can be made feasible using specialized LAB strains that have been reported to produce ferulic acid esterases. The present study aimed at screening a panel of LAB isolates for their ability to release phenolics from agrowaste materials like rice bran and their biotransformation to industrially important compounds such as ferulic acid, 4-ethyl phenol, vanillic acid, vanillin, and vanillyl alcohol. Bacterial isolates were evaluated using ferulic acid esterase, ferulic acid decarboxylase, and vanillin dehydrogenase assays. This work highlights the importance of lactic acid bacteria in phenolic biotransformations for the development of food grade flavours and additives. PMID:24066293

  6. Phenolic biotransformations during conversion of ferulic acid to vanillin by lactic acid bacteria.

    PubMed

    Kaur, Baljinder; Chakraborty, Debkumar; Kumar, Balvir

    2013-01-01

    Vanillin is widely used as food additive and as a masking agent in various pharmaceutical formulations. Ferulic acid is an important precursor of vanillin that is available in abundance in cell walls of cereals like wheat, corn, and rice. Phenolic biotransformations can occur during growth of lactic acid bacteria (LAB), and their production can be made feasible using specialized LAB strains that have been reported to produce ferulic acid esterases. The present study aimed at screening a panel of LAB isolates for their ability to release phenolics from agrowaste materials like rice bran and their biotransformation to industrially important compounds such as ferulic acid, 4-ethyl phenol, vanillic acid, vanillin, and vanillyl alcohol. Bacterial isolates were evaluated using ferulic acid esterase, ferulic acid decarboxylase, and vanillin dehydrogenase assays. This work highlights the importance of lactic acid bacteria in phenolic biotransformations for the development of food grade flavours and additives.

  7. The Use of Endophytes to Obtain Bioactive Compounds and Their Application in Biotransformation Process

    PubMed Central

    Pimentel, Mariana Recco; Molina, Gustavo; Dionísio, Ana Paula; Maróstica Junior, Mário Roberto; Pastore, Gláucia Maria

    2011-01-01

    Endophytes are microorganisms that reside asymptomatically in the tissues of higher plants and are a promising source of novel organic natural metabolites exhibiting a variety of biological activities. The laboratory of Bioaromas (Unicamp, Brazil) develops research in biotransformation processes and functional evaluation of natural products. With the intent to provide subsidies for studies on endophytic microbes related to areas cited before, this paper focuses particularly on the role of endophytes on the production of anticancer, antimicrobial, and antioxidant compounds and includes examples that illustrate their potential for human use. It also describes biotransformation as an auspicious method to obtain novel bioactive compounds from microbes. Biotransformation allows the production of regio- and stereoselective compounds under mild conditions that can be labeled as “natural,” as discussed in this paper. PMID:21350663

  8. Stability and biotransformation of various dietary anthocyanins in vitro.

    PubMed

    Fleschhut, Jens; Kratzer, Frank; Rechkemmer, Gerhard; Kulling, Sabine E

    2006-02-01

    Anthocyanins, which are found in high concentrations in fruit and vegetable, may play a beneficial role in retarding or reversing the course of chronic degenerative diseases. However, little is known about the biotransformation and the metabolism of anthocyanins so far. The aim of the study was to investigate possible transformation pathways of anthocyanins by human faecal microflora and by rat liver microsomes as a source of cytochrome P450 enzymes as well as of glucuronyltransferases. Pure anthocyanins, an aqueous extract of red radish as well as the assumed degradation products were incubated with human faecal suspension. The incubation mixtures were purified by solid-phase extraction and analysed by HPLC/DAD/MS and GC/MS. Quantification was done by the external standard method. Furthermore the biotransformation of anthocyanins by incubation with rat liver microsomes in the presence of the cofactor NADPH (as a model for the phase I oxidation) and in the presence of activated glucuronic acid (as a model for the phase II glucuronidation) was investigated. Glycosylated and acylated anthocyanins were rapidly degraded by the intestinal microflora after anaerobic incubation with a human faecal suspension. The major stable products of anthocyanin degradation are the corresponding phenolic acids derived from the B-ring of the anthocyanin skeleton. Anthocyanins were not metabolised by cytochrome P450 enzymes, neither hydroxylated nor demethylated. However they were glucuronidated by rat liver microsomes to several products. The gut microflora seem to play an important role in the biotransformation of anthocyanins. A rapid degradation could be one major reason for the poor bioavailability of anthocyanins in pharmacokinetic studies described so far in the literature. The formation of phenolic acids as the major stable degradation products gives an important hint to the fate of anthocyanins in vivo.

  9. Complex Biotransformations Catalyzed by Radical S-Adenosylmethionine Enzymes*

    PubMed Central

    Zhang, Qi; Liu, Wen

    2011-01-01

    The radical S-adenosylmethionine (AdoMet) superfamily currently comprises thousands of proteins that participate in numerous biochemical processes across all kingdoms of life. These proteins share a common mechanism to generate a powerful 5′-deoxyadenosyl radical, which initiates a highly diverse array of biotransformations. Recent studies are beginning to reveal the role of radical AdoMet proteins in the catalysis of highly complex and chemically unusual transformations, e.g. the ThiC-catalyzed complex rearrangement reaction. The unique features and intriguing chemistries of these proteins thus demonstrate the remarkable versatility and sophistication of radical enzymology. PMID:21771780

  10. Employability Team Interaction Analysis: An Exploratory Study, Stage III.

    ERIC Educational Resources Information Center

    Munger, Paul F.; And Others

    This report provides information about Employability Development (E.D.) Team member interaction and its effect on enrollees based on a national sample of 31 sites. Findings indicated satisfaction with the E.D. Team approach by both enrollees and team members. Differences among job roles were found in operating philosophy, level of training, and…

  11. Employability in Online Higher Education: A Case Study

    ERIC Educational Resources Information Center

    Silva, Ana Paula; Lourtie, Pedro; Aires, Luisa

    2013-01-01

    Over the past 15 years, learning in distance education universities has become more interactive, flexible, collaborative, and participative. Nevertheless, some accounts have highlighted the importance of developing more instrumental and standardized educational practices to answer the challenges of employability. In fact, the choice of skills that…

  12. When Subsidized Employment Is Terminated: A Follow-Up Study.

    ERIC Educational Resources Information Center

    Randolph, Alice H.; Swann, Karen

    1980-01-01

    To ease the transition of laid-off Comprehensive Employment and Training Act (CETA) workers, a series of workshops were held to provide information and identify needs. Although most participants were satsified with CETA services, they did not feel they received help in finding new jobs. (JAC)

  13. Background Study on Employment and Labour Market in Hungary.

    ERIC Educational Resources Information Center

    Horvath, Reka; Abraham, Arpad; Horvath, Tibor; Kopeczi-Bocz, Tamas

    Most deficiencies of the Hungarian labor market emerge from a combination of the transition crisis and special features of the economy or transition process. The most crucial labor market problem is low employment. Negative impacts are high taxation and social security contributions; reduced investment, job creation, and economic growth; and…

  14. Background Study on Employment and Labour Market in Estonia.

    ERIC Educational Resources Information Center

    Eamets, Raul; Philips, Kaia; Annus, Tiina

    During the years 1989-1997 in Estonia, employment has decreased; unemployment and inactivity have increased. Females have tended to move to inactivity while males have become unemployed. The wage patterns are very flat relative to those in market economies. Estonia has opted for very low levels of unemployment benefits, pensions, and a low minimum…

  15. Biotransformation and detoxification of inorganic arsenic in Bombay oyster Saccostrea cucullata.

    PubMed

    Zhang, Wei; Guo, Zhiqiang; Zhou, Yanyan; Liu, Huaxue; Zhang, Li

    2015-01-01

    Arsenic (As) exists as the toxic inorganic forms in marine water and sediment, while marine oysters usually accumulate high As contents mostly as the less toxic organic forms. It has not yet been clear that how As is biotransformed in marine oysters. This study therefore investigated the biotransformation and detoxification of two inorganic As forms (As(III) and As(V)) in Bombay oyster Saccostrea cucullata after waterborne exposures for 30 days. Seven treatments of dissolved As exposure (clean seawater, 1, 5, 20 mg/L As(III), and 1, 5, 20 mg/L As(V)) were performed. Body As concentration increased significantly after all As exposure treatments except 1mg/L As(V). Total As, As(III), and As(V) concentration were positive correlated with glutathione-S-transferases (GST) activities, suggesting GST might play an important role in the As biotransformation and detoxification process. Organic As species were predominant in control and the low As exposed oysters, whereas a large fraction of As was remained as the inorganic forms in the high As exposed oysters, suggesting As could be biotransformed efficiently in the oysters in clean or light contaminated environment. The results of As speciation demonstrated the As biotransformation in the oysters included As(V) reduction, methylation to monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA), and subsequent conversion to arsenobetaine (AsB). More As was distributed in the subcellular metallothionein-like proteins fraction (MTLP) functioning sequestration and detoxification in the inorganic As exposed oysters, suggesting it was also a strategy for oysters against As stress. In summary, this study elucidated that marine oysters had high ability to accumulate, biotransform, and detoxify inorganic As.

  16. Biotransformation of tissue-specific hormone tibolone with fungal culture Trichothecium roseum

    NASA Astrophysics Data System (ADS)

    Shah, Syed Adnan Ali; Sultan, Sadia; Zaimi bin Mohd Noor, M.

    2013-06-01

    Whole cells based biotransformation is an important tool for bioconversion of steroids. It can be used to synthesize biologically potent compounds with diverse structures. Biotransformation of tissue-specific hormone tibolone (1) with Trichothecium roseum (ATCC 13411) has being carried out for the first time. Two new and three known metabolites 2-6 were isolated from fermentation of tibolone (1) with Trichothecium roseum and their structures were characterized by 2D NMR spectroscopy and mass spectrometry. The relative stereochemistry of new metabolites 5 and 6 was deduced by 2D NOESY experiments. The effect of cultures on tibolone structural modifications and time-course studies has also been conducted.

  17. Case-control study of respiratory cancer and employment

    SciTech Connect

    Glazer, E.R.; Chiang, M.L.

    1984-04-01

    A multiple logistic risk-analysis procedure was used to compare data from 346 case/control pairs to determine occupational/industrial risk factors for respiratory cancer. The duration of employment was considered in blue-collar production occupations. Five industrial categories were included: shipyard, petrochemical, metal-related, construction and a grouping of other occupations under a single heading. The bulk of this grouped category was made up of blue collar employees in the industries of transportation, food production, wholesale and retail trade, professional services, and public administration. Specific attention was given to asbestos exposure, cigarette smoking, educational level attained, and dietary factors such as consumption of vegetables, fruits, and alcohol. A moderately elevated risk for respiratory cancer existed among employees in the metal industry and grouped categories when employment was over 30 years duration. In the metal industry this increase was almost entirely due to a larger than expected number of cases of larynx cancer.

  18. Biotransformations and biological activities of hop flavonoids.

    PubMed

    Karabin, Marcel; Hudcova, Tereza; Jelinek, Lukas; Dostalek, Pavel

    2015-11-01

    Female hop cones are used extensively in the brewing industry, but there is now increasing interest in possible uses of hops for non-brewing purposes, especially in the pharmaceutical industry. Among pharmaceutically important compounds from hops are flavonoids, having proven anticarcinogenic, antioxidant, antimicrobial, anti-inflammatory and estrogenic effects. In this review we aim to present current knowledge on the biotransformation of flavonoids from hop cones with respect to products, catalysis and conversion. A list of microbial enzymatic reactions associated with gastrointestinal microbiota is presented. A comparative analysis of the biological activities of hop flavonoids and their biotransformation products is described, indicating where further research has potential for applications in the pharmaceutical industry.

  19. Biotransformation in Egyptian spiny mouse Acomys cahirinus.

    PubMed

    Watkins, J B; LaFollette, J W; Sanders, R A

    1995-01-01

    The activities of several representative biotransformation enzymes were determined in male and female spiny mouse tissues. Cytochrome P450 monooxygenase activity toward benzo(a)pyrene was significantly greater in female spiny mouse intestine than in males. Activity toward benzphetamine in both sexes was high in the liver, with little activity in the kidney and intestine. Sulfotransferase activity was high in kidney and intestine of female spiny mice but undetectable in the same tissues in males. Hepatic glutathione S-transferase activity towards 1-chloro-2,4-dinitrobenzene in females was significantly higher than in males. UDP-Glucuronosyltransferase activity toward 1-naphthol in both sexes in the kidney was significantly higher than hepatic and intestinal activity. Intestinal N-acetyltransferase activity towards 2-aminofluorene and beta-naphthylamine was significantly greater in females than males. No consistent relation appeared to exist between biotransformation activities in spiny mouse and those in other related rodent species.

  20. Applied biotransformations in green solvents.

    PubMed

    Hernáiz, María J; Alcántara, Andrés R; García, José I; Sinisterra, José V

    2010-08-16

    The definite interest in implementing sustainable industrial technologies has impelled the use of biocatalysts (enzymes or cells), leading to high chemo-, regio- and stereoselectivities under mild conditions. As usual substrates are not soluble in water, the employ of organic solvents is mandatory. We will focus on different attempts to combine the valuable properties of green solvents with the advantages of using biocatalysts for developing cleaner synthetic processes.

  1. A new and fast DLLME-CE method for the enantioselective analysis of zopiclone and its active metabolite after fungal biotransformation.

    PubMed

    de Albuquerque, Nayara Cristina Perez; de Gaitani, Cristiane Masetto; de Oliveira, Anderson Rodrigo Moraes

    2015-05-10

    Zopiclone (ZO) is a chiral drug that undergoes extensive metabolism to N-desmethylzopiclone (N-Des-ZO) and zopiclone-N-oxide (N-Ox-ZO). Pharmacological studies have shown (S)-N-Des-ZO metabolite presents anxiolytic activity and a patent for this metabolite was requested for anxiety treatment and related disorders. In this context, biotransformation employing fungi may be a promising strategy to obtain N-Des-ZO. To perform the biotransformation study in this work, an enantioselective method based on capillary electrophoresis (CE) and dispersive liquid-liquid microextraction (DLLME) was developed. CE analyses were carried out in sodium phosphate buffer (pH 2.5; 50mmolL(-1)) containing 0.5% (w/v) carboxymethyl-β-CD, at a constant voltage of +25kV. DLLME was conducted using 2mL of liquid culture medium pH 9.5. Chloroform (100μL) and methanol (300μL) were employed as extraction and disperser solvent, respectively. After CE and DLLME optimization, the analytical method was fully validated. The method was linear over a concentration range of 90-6000ngmL(-1) for each ZO enantiomer (r>0.999) and 50-1000ngmL(-1) for each N-Des-ZO enantiomer (r>0.998). Absolute recovery of 51 and 82% was achieved for N-Des-ZO and ZO, respectively. The accuracy and precision results agreed with the EMA (European Medicines Agency) guideline, and so did the stability study. Application of the developed method in a biotransformation study was conducted in order to investigate the ability of fungi, belonging to the genus Cunninghamella, in metabolizing ZO chiral drug. Fungi Cunninghamella elegans ATCC 10028B and Cunninghamella echinulata var elegans ATCC 8688A demonstrated to be able to enantioselectively biotransform ZO to its active metabolite, N-Des-ZO. Therefore, the proposed goals of this work, i.e. a fast DLLME-CE method and an outstanding strategy to obtain N-Des-ZO, were successfully attained.

  2. Employment conditions and health inequities: a case study of Brazil.

    PubMed

    Dias, Elizabeth Costa; Oliveira, Roberval Passos de; Machado, Jorge H; Minayo-Gomez, Carlos; Perez, Marco Antonio Gomes; Hoefel, Maria da Graça L; Santana, Vilma Sousa

    2011-12-01

    This paper was prepared for the Employment Conditions and Health Inequalities Knowledge Network (EMCONET), part of the WHO Commission on the Social Determinants of Health. We describe the Brazilian context of employment conditions, labor conditions and health, their characteristics and causal relationships. The social, political and economic factors that influence these relationships are also presented with an emphasis on social inequalities, and how they are reproduced within the labor market and thereby affect the health and wellbeing of workers. A literature review was conducted in SciELO, LILACS, Google and Google Scholar, MEDLINE and the CAPES Brazilian thesis database. We observed that there are more workers operating in the informal sector than in the formal sector and these former have no social insurance or any other social benefits. Work conditions and health are poor in both informal and formal enterprises since health and safety labor norms are not effective. The involvement of social movements and labor unions in the elaboration and management of workers' health polices and programs with universal coverage, is a promising initiative that is underway nationwide.

  3. Biotransformation of Rutin Using Crude Enzyme from Rhodopseudomonas palustris.

    PubMed

    Guan, Chun-Jie; Ji, Yu-Jia; Hu, Jia-Lin; Hu, Chao-Nan; Yang, Fei; Yang, Guan-E

    2017-04-01

    Rhodopseudomonas palustris was selected for the ability to grow in diglycosylated flavonoids-based media, exhibited deglycosylation activity. The present study aimed to investigate the ability of a crude enzyme from Rhodopseudomonas palustris to transform rutin. Our results showed the crude enzyme was found to transform rutin to quercetin via isoquercitrin. The maximum enzyme activities were observed at pH 7.0, 25 °C, and rutin concentration of 1.0 mg mL(- 1). Under optimal conditions, 13.11 μM rutin was biotransformed into 6.86 μM isoquercitrin and 11.64 μM quercetin after 11 and 21 h, respectively. The study demonstrates an eco-friendly and potential economically viable 'green' conversion route to convert rutin to isoquercitrin and quercetin, which is of great interest, considering the therapeutic applications of isoquercitrin and quercetin. The specific biotransformation of rutin to isoquercitrin and quercetin, using the crude enzyme from Rhodopseudomonas palustris, may potentially serve as a new method for industrial production of isoquercitrin and quercetin.

  4. Feline hepatic biotransformation of diazepam: Differences between cats and dogs.

    PubMed

    van Beusekom, Cyrina D; van den Heuvel, Jeroen J M W; Koenderink, Jan B; Russel, Frans G M; Schrickx, Johannes A

    2015-12-01

    In contrast to humans and dogs, diazepam has been reported to induce severe hepatic side effects in cats, particularly after repeated dosing. With the aim to elucidate the mechanisms underlying this apparent sensitivity of cats to drug-induced liver injury, in a series of in vitro experiments, the feline-specific biotransformation of diazepam was studied with liver microsomes obtained from cats and dogs and the possible inhibition of the bile salt export pump (Bsep) was measured in isolated membrane vesicles overexpressing feline and canine Bsep. In line with previous in vivo studies, the phase I metabolites nordiazepam, temazepam and oxazepam were measurable in microsomal incubations, although enzyme velocity of demethylases and hydroxylases differed significantly between cats and dogs. In cats, the main metabolite was temazepam, which also could be glucuronidated. In contrast to dogs, no other glucuronidated metabolites could be observed. In addition, in the membrane vesicles an inhibition of the transport of the Bsep substrate taurocholic acid could be observed in the presence of diazepam and its metabolites. It was concluded that both mechanisms, the slow biotransformation of diazepam as well the inhibition of the bile acid efflux that results in an accumulation of bile acids in the hepatocytes, seem to contribute to the liver injury observed in cats following repetitive treatment with diazepam.

  5. Achieving elongated lesions employing cardiac cryoablation: a preclinical evaluation study.

    PubMed

    Seger, M; Fischer, G; Handler, M; Stöger, M; Nowak, C-N; Hintringer, F; Klima, G; Baumgartner, C

    2012-10-01

    Cardiac cryoablation applied for treating cardiac arrhythmias has shown promising results after intervention, particularly for the creation of elongated lesions. A model for simulating and assessing cryoablation interventions was developed, evaluated and validated with animal experiments. We employed two simulations of different freezing outlet settings for a loop shaped cryocatheter, applying Pennes heat equation for cardiac tissue. Our experiments demonstrated that an equidistantly spaced freezing outlet distribution of 5mm led to an improved formation of lesions, i.e., elongated lesions were observed throughout the transmural cardiac volume and on the epicardial structure. A complete transmural frozen lesion was not achieved with a freezing outlet distance of 10mm. These simulation results could be experimentally verified by morphological and histological examinations. Using our simulation model we were able to optimize the intervention procedure by predicting and assessing the freezing process. This should further increase the success rate of cardiac cryoablation in clinical interventions.

  6. In vitro biotransformation of decabromodiphenyl ether (BDE-209) and Dechlorane Plus flame retardants: a case study of ring-billed gull breeding in a pollution hotspot in the St. Lawrence River, Canada.

    PubMed

    Chabot-Giguère, Bernice; Letcher, Robert J; Verreault, Jonathan

    2013-05-01

    Decabromodiphenyl ether (deca-BDE) mixture (~97% of BDE-209) is now facing usage restrictions worldwide, which is leading to increased utilization of a series of alternative, replacement flame retardant (FR) products. Among these, Dechlorane Plus (DP) is receiving growing attention as this FR is increasingly being detected in wildlife samples, including birds from North America, Europe and Asia. Recent survey conducted in a known FR hotspot in the St. Lawrence River basin near Montreal (QC, Canada) revealed unexpectedly high detection frequencies and concentrations of BDE-209 and DP isomers (syn- and anti-DP) in the liver of breeding ring-billed gulls (Larus delawarensis) (RBGUs). Despite the global distribution of these current-use FRs, there is to our knowledge no study that has addressed the in vitro biotransformation of BDE-209 and DP isomers in birds. This study aimed at understanding the in vitro metabolism of BDE-209 and syn- and anti-DP using liver microsomes of Montreal-breeding RBGUs. Although BDE-15 (positive assay control) was consistently and positively depleted over the 90-min time frame of the in vitro assay, no depletion was observed for BDE-209 and DP isomers. These results suggest that CYP isoenzyme-mediated reductive dehalogenation of BDE-209 and DP is not likely to be a substantial metabolic pathway in RBGUs. However, investigations on deiodinases (expression, activity) should be considered in future studies as these enzymes have been suggested to be involved in the sequential debromination of BDE-209 in fish and human studies. High levels of BDE-209 determined in liver of RBGUs that strongly correlated with those of known or suggested BDE-209 debromination products (hepta- through nona-BDEs) may thus be indicative of concomitant dietary (e.g., fish consumption) and environmental exposure in the greater Montreal area, combined with poor or lack of metabolic capability toward these FRs.

  7. Biotransformation of chlorinated aliphatic compounds by mixed nitrifying cultures

    SciTech Connect

    Wilber, G.G.; Chakkamadathil, S.V.

    1995-12-31

    The ability of pure cultures of nitrifying bacteria, such as Nitrosomonas europaea, to oxidize chlorinated aliphatic compounds has been demonstrated previously in laboratory experiments. In the current study, mixed nitrifying cultures originating from a municipal wastewater plant were also tested for the ability to biotransform chlorinated aliphatic compounds, including trichloroethene (TCE). A number of variables were tested, including the effects of two different concentrations of TCE, the effect of culture density, and the influence of the primary substrate, ammonia, on the initial rate of TCE biotransformation. The primary conclusions of the research include the following. The mixed nitrifying cultures did exhibit the ability to transform TCE, and the initial rate of transformation (before oxygen limitations became significant) was directly proportional to the culture density. In general, the transformation rate of TCE was slightly faster at an initial concentration of 0.1 mg/L than at 1 mg/L. Lastly, high initial ammonia concentrations (300 mg/L) resulted in faster initial rates of TCE transformation than in cultures which started with lower ammonia concentrations.

  8. Biotransformation of di(2-ethylhexyl)phthalate by rainbow trout

    SciTech Connect

    Barron, M.G.; Hayton, W.L.

    1995-05-01

    The biotransformation of di(2-ethylhexyl)phthalate (DEHP) was studied in rainbow trout (Oncorhynchus mykiss) following intravascular administration. Methyl-esterified metabolites were identified using rodent-derived standards and non-linear gradient elution HPLC; metabolites were confirmed by gas chromatography. Similarities between the biotransformation of DEHP by rainbow trout and mammalian species included (a) mono-ethylhexyl phthalate (MEHP) appeared to be the obligatory first step in DEHP metabolism; (b) the phthalate ring was not oxidized; (c) phthalic acid was a minor metabolite; and (d) several metabolites contained multiple oxidations of the 2-ethylhexyl moiety of MEHP. No metabolites unique to rainbow trout were identified. However, fewer oxidized metabolites were identified in rainbow trout than in mammalian species, possibly due to limited mitochondrial metabolism of MEHP in rainbow trout. The amount of biliary MEHP glucuronide after intravascular administration of DEHP was substantially less than reported in rainbow trout exposed to DEHP via the water. Results confirmed that DEHP metabolism in rainbow trout proceeds by initial rapid formation of MEHP, followed by excretion or extensive oxidation by microsomal P450.

  9. Biotransformation of extracted digitoxin from Digitalis lanata by Streptomyces.

    PubMed

    Keshk, S; Mostafa, M; Tawfik, F; Elshemy, I

    2011-06-01

    The biotransformation of digitoxin and some of its derivatives extracted from Digitalis lanata by Streptomyces isolated species was investigated. Cultures of a Streptomyces strain designated EUSA2003B, isolated from an Egyptian soil sample, efficiently induced selective 12beta-hydroxylation of the steroid aglycone of digitoxin (DT) and its alpha-acetyl and beta-methyl derivatives. The transformation reaction was performed within a 5-day fermentation process, products were isolated and their aglycone moiety was obtained by acid hydrolysis and their structures were elucidated by 13C and 1H NMR. The biotransformation resulted mainly digoxin (DG, approximately 87%), meanwhile, digoxigenone (DGON, approximately 7.0%) was also afforded as a side product. The present study revealed that: 1-Streptomyces isolate EUSA2003B harbors its specific 12beta-hydroxlase and has the capability to transform DT and it's alpha-acetyl and beta-methyl derivatives into their corresponding digoxins at reasonable yields. 2-The minor structural differences in the trisaccharide side chain seemed ineffective on the transformational capability of this organism. 3-The Streptomyces might also possess a specific glycosidase that splits the saccharidic side chain beside another dehydrogenase that oxidizes C3 at the steroid nucleus into its ketone form (DGON).

  10. Aspects of pharmacodynamics and biotransformation of the glucocorticoid resocortol butyrate.

    PubMed

    Coert, A; Verheijen, F; Horspool, L J I; Mol, J A

    2004-10-01

    Aspects of the biotransformation and pharmacodynamics of the novel glucocorticoid resocortol butyrate (RCB) and its metabolites were assessed in vitro and in vivo in comparison with selected reference compounds. The main route of biotransformation of ((3)H)-RCB in the skin and the liver was 5alpha-reduction of the A-ring followed by reduction of the 3-carbonyl group. In the liver, metabolism was much more rapid than in the skin and 5beta-reduction also occurred. RCB had a relative binding affinity for the glucocorticoid receptor similar to that of triamcinolone acetonide, about 1.5 times that of dexamethasone, three times that of betamethasone valerate (BMV) and 10-14 times that of cortisol. The metabolites of RCB displayed only low to very low affinities for the receptor. The suppression of the hypothalamic-pituitary-adrenal axis was investigated in placebo- and positive-controlled studies in dogs by measurement of basal and corticotrophin-releasing hormone (CRH) stimulated plasma cortisol concentrations. The AUC of the plasma cortisol vs. time curve following CRH stimulation, a measure of adrenal suppression, was reduced significantly after topical application of BMV compared with the pretreatment values. The AUC in the RCB group was not reduced significantly. Adrenocorticotrophic hormone concentrations were not affected. Oral administration of RCB did not suppress adrenocortical function, whereas BMV induced almost complete suppression of basal and CRH-induced cortisol concentrations. The pharmacodynamics of RCB makes it a relatively safe glucocorticosteroid for topical application.

  11. ANAEROBIC DDT BIOTRANSFORMATION: ENHANCEMENT BY APPLICATION OF SURFACTANTS AND LOW OXIDATION REDUCTION POTENTIAL

    EPA Science Inventory

    Enhancement of anaerobic DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl) ethane) biotransformation by mixed cultures was studied with application of surfactants and oxidation reduction potential reducing agents. Without amendments, DDT transformation resulted mainly in the pr...

  12. Biotransformation of a cage-like diels-alder adduct and derivatives by Mucor ramosissimus samutsevitsch

    PubMed Central

    Ito, Felicia Megumi; Mena, Ana Elisa Maciel; Marques, Maria Rita; de Lima, Dênis Pires; Beatriz, Adilson

    2009-01-01

    The present study aimed to evaluate the ability for biotransformation of the Diels-Alder adduct tricyclo[6.2.1.02,7]undeca-4,9-dien-3,6-dione (1) and two synthetic derivatives by the saprobe fungus Mucor ramosissimus Samutsevitsch. Products from oxidation, isomerization and, regioselective and enantioselective reduction were achieved. PMID:24031400

  13. Influence of Aroclor 1242 concentration on polychlorinated biphenyl biotransformations in Hudson River test tube microcosms

    SciTech Connect

    Fish, K.M.

    1996-08-01

    PCBs are a family of compounds sold with various levels of chlorination and under different trade names. They have accumulated in soils, sediments, and biota, raising concerns about possible health risks. The upper Hudson River was contaminated with Aroclor 1242. This study examines the influence of Aroclor concentration on PCB biotransformations in the upper Hudson River sediment. 6 refs., 3 figs.

  14. ANAEROBIC DDT BIOTRANSFORMATION: ENHANCEMENT BY APPLICATION OF SURFACTANTS AND LOW OXIDATION REDUCTION POTENTIAL

    EPA Science Inventory

    Enhancement of anaerobic DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl) ethane) biotransformation by mixed cultures was studied with application of surfactants and oxidation reduction potential reducing agents. Without amendments, DDT transformation resulted mainly in the pr...

  15. Biotransformation of limonene by an endophytic fungus using synthetic and orange residue-based media.

    PubMed

    Bier, Mário Cesar Jucoski; Medeiros, Adriane Bianchi Pedroni; Soccol, Carlos Ricardo

    2017-02-01

    Aroma and fragrances have high commercial value for use in food, cosmetics and perfumes. The biotransformation of terpenes by microorganisms represents an attractive alternative method for production of flavourings. Endophytic fungi offer a great potential for the production of several groups of compounds; however, few studies have evaluated the biotransformation of limonene. Following preliminary studies on the biotransformation of limonene, submerged fermentation was carried out using an endophytic fungus isolated from Pinus taeda and identified as Phomopsis sp. The presence of several biotransformation products was detected and identified by mass spectrometry (GC-MS). The studied strain showed a divergent metabolic behaviour, as compounds of interest such as α-terpineol, carvone, and limoneno-1,2-diol were produced under different conditions. In addition to the minor metabolites terpinen-4-ol, menthol and carveol, this strain also produced major metabolites, including 0.536 g L(-1) carvone and 2.08 g L(-1) limonene-1,2-diol in synthetic medium and 2.10 g L(-1) limonene-1,2-diol in a natural orange extract medium with single fed-batch, while the cyclic fed-batch resulted in concentrations less than 1 g L(-1). Therefore, our study produced a wide variety of limonene derivatives at a high concentration using a natural medium and a newly isolated endophytic fungal strain.

  16. Involving Private Employers in CETA Programs: A Case Study. R & D Monograph 75.

    ERIC Educational Resources Information Center

    Lecht, Leonard A.; Matland, Marc A.

    Case studies were conducted of nine Comprehensive Employment and Training Act (CETA) prime sponsors which had records of successful cooperation with business firms. To identify strategies employed for increasing the participation of private employers in CETA programs, information was obtained at each site about the local program, labor market,…

  17. Who Do You Know? A Study of Connectedness in Online Education and Employment

    ERIC Educational Resources Information Center

    Oguz, Faith; Poole, Nancy

    2013-01-01

    This study explored the relationship of online course intensity to the development of social networks and the impact of social networks on obtaining employment or employment information to develop a better understanding of the factors that lead to improved employment outcomes and information-gathering. Graduates from three ALA-accredited programs…

  18. Working While Studying: The Impact of Term-Time Employment on Dropout Rates

    ERIC Educational Resources Information Center

    Hovdhaugen, Elisabeth

    2015-01-01

    There are many possible reasons why students leave university prior to degree completion, and one of the more commonly cited is being employed while studying. This paper analyses the impact of employment status on dropout rates using survival analysis. It finds that employment status does have an impact on dropout rates; students who work full…

  19. Working While Studying: The Impact of Term-Time Employment on Dropout Rates

    ERIC Educational Resources Information Center

    Hovdhaugen, Elisabeth

    2015-01-01

    There are many possible reasons why students leave university prior to degree completion, and one of the more commonly cited is being employed while studying. This paper analyses the impact of employment status on dropout rates using survival analysis. It finds that employment status does have an impact on dropout rates; students who work full…

  20. Employment of Young Adults with Disabilities in Dubai--A Case Study

    ERIC Educational Resources Information Center

    Alborno, Nadera; Gaad, Eman

    2012-01-01

    The authors investigated the implementation of the United Arab Emirates Federal Law regarding the employment of people with disabilities. They used a case study evaluation of an employment program initiated by a private national landscaping company in Dubai providing training and employment opportunities for young adults with varied physical and…

  1. Employment of Young Adults with Disabilities in Dubai--A Case Study

    ERIC Educational Resources Information Center

    Alborno, Nadera; Gaad, Eman

    2012-01-01

    The authors investigated the implementation of the United Arab Emirates Federal Law regarding the employment of people with disabilities. They used a case study evaluation of an employment program initiated by a private national landscaping company in Dubai providing training and employment opportunities for young adults with varied physical and…

  2. Who Do You Know? A Study of Connectedness in Online Education and Employment

    ERIC Educational Resources Information Center

    Oguz, Faith; Poole, Nancy

    2013-01-01

    This study explored the relationship of online course intensity to the development of social networks and the impact of social networks on obtaining employment or employment information to develop a better understanding of the factors that lead to improved employment outcomes and information-gathering. Graduates from three ALA-accredited programs…

  3. The Federal Work-Study Program: Impacts on Academic Outcomes and Employment. Policy Brief

    ERIC Educational Resources Information Center

    Center for Analysis of Postsecondary Education and Employment, 2015

    2015-01-01

    Student employment subsidies are one of the largest types of employment subsidies and one of the oldest forms of student aid. The Federal Work-Study program (FWS) is the largest student employment subsidy program; since 1964, it has provided about $1 billion per year to cover 75 percent of wages for student employees, who typically work on campus…

  4. (Bio)transformation of 2,4-dinitroanisole (DNAN) in Soils

    PubMed Central

    Olivares, Christopher I.; Abrell, Leif; Khatiwada, Raju; Chorover, Jon; Sierra-Alvarez, Reyes; Field, Jim A.

    2015-01-01

    Recent studies have begun to assess the environmental fate and toxicity of 2,4-dinitroanisole (DNAN), an insensitive munition compound of interest to defense agencies. Aerobic and anaerobic DNAN biotransformation in soils was evaluated in this study. Under aerobic conditions, there was little evidence of transformation; most observed removal was attributed to adsorption and subsequent slow chemical reactions. Under anaerobic conditions, DNAN was reductively (bio)transformed and the rate of the transformation was positively correlated with soil organic carbon (OC) up to a threshold of 2.07% OC. H2 addition enhanced the nitroreduction rate compared to endogenous treatments lacking H2. Heat-killed treatments provided rates similar to the endogenous treatment, suggesting that abiotic factors play a role in DNAN reduction. Ten (bio)transformation products were detected by high-resolution mass spectrometry. The proposed transformation pathway involves reduction of DNAN to aromatic amines, with putative reactive nitroso-intermediates coupling with the amines to form azo dimers. Secondary reactions include N-alkyl substitution, O-demethylation (sometimes followed by dehydroxylation), and removal of an N-containing group. Globally, our results suggest that the main reaction DNAN undergoes in anaerobic soils is nitroreduction to 2-methoxy-5-nitroaniline (MENA) and 2,4-diaminoanisole (DAAN), followed by anaerobic coupling reactions yielding azo-dimers. The dimers were subsequently subject to further (bio)transformations. PMID:26551225

  5. Comparative contribution of trophic transfer and biotransformation on arsenobetaine bioaccumulation in two marine fish.

    PubMed

    Zhang, Wei; Guo, Zhiqiang; Zhou, Yanyan; Chen, Lizhao; Zhang, Li

    2016-10-01

    Marine fish can accumulate high arsenic (As) concentrations, with arsenobetaine (AsB) as the major species in the body. However, whether the high AsB accumulation in fish occurs mainly through trophic transfer from diet or biotransformation in the fish body remains unclear. This study investigated the trophic transfer and biotransformation of As in two marine fish (seabream Acanthopagrus schlegeli and grunt Terapon jarbua) fed artificial and clam diets for 28 d. The different diets contained different proportions of inorganic [As(III) and As(V)] and organic [methylarsenate (MMA), dimethylarsenate (DMA), and AsB] As compounds. Positive correlations were observed between the accumulated As concentrations and AsB concentrations in both fish, suggesting that AsB contributed to the accumulation of total As in marine fish. Based on the calculated total input of AsB and detected AsB concentrations in the muscle of the seabream and grunt, the ingested amounts of AsB accounted for 0.1-0.3%, 8.1-14.4% of detected AsB concentrations, respectively, in the muscle of seabream and grunt fish species, suggesting that AsB was mainly biotransformed versus trophically transferred in these marine fish. In summary, this study demonstrates that marine fish prefer to biotransform inorganic As forms into AsB, resulting in high bioaccumulation of total As.

  6. (Bio)transformation of 2,4-dinitroanisole (DNAN) in soils.

    PubMed

    Olivares, Christopher I; Abrell, Leif; Khatiwada, Raju; Chorover, Jon; Sierra-Alvarez, Reyes; Field, Jim A

    2016-03-05

    Recent studies have begun to assess the environmental fate and toxicity of 2,4-dinitroanisole (DNAN), an insensitive munition compound of interest to defense agencies. Aerobic and anaerobic DNAN biotransformation in soils was evaluated in this study. Under aerobic conditions, there was little evidence of transformation; most observed removal was attributed to adsorption and subsequent slow chemical reactions. Under anaerobic conditions, DNAN was reductively (bio)transformed and the rate of the transformation was positively correlated with soil organic carbon (OC) up to a threshold of 2.07% OC. H2 addition enhanced the nitroreduction rate compared to endogenous treatments lacking H2. Heat-killed treatments provided rates similar to the endogenous treatment, suggesting that abiotic factors play a role in DNAN reduction. Ten (bio)transformation products were detected by high-resolution mass spectrometry. The proposed transformation pathway involves reduction of DNAN to aromatic amines, with putative reactive nitroso-intermediates coupling with the amines to form azo dimers. Secondary reactions include N-alkyl substitution, O-demethylation (sometimes followed by dehydroxylation), and removal of an N-containing group. Globally, our results suggest that the main reaction DNAN undergoes in anaerobic soils is nitroreduction to 2-methoxy-5-nitroaniline (MENA) and 2,4-diaminoanisole (DAAN), followed by anaerobic coupling reactions yielding azo-dimers. The dimers were subsequently subject to further (bio)transformations. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Biotransformation potential of 6:2 fluorotelomer sulfonate (6:2 FTSA) in aerobic and anaerobic sediment.

    PubMed

    Zhang, Shu; Lu, Xiaoxia; Wang, Ning; Buck, Robert C

    2016-07-01

    Aqueous film-forming foam (AFFF) products are used in industrial and military firefighting around the globe. These products contain fluoroalkylthioamido sulfonates, fluoroalkylthiobetaine, and other related substances as the major ingredients, which can be biotransformed in the environment to form 6:2 fluorotelomer sulfonate (6:2 FTSA, F(CF2)6CH2CH2SO3-) as one of the major initial biotransformation products. Limited information is available on 6:2 FTSA aerobic biotransformation in activated sludge and pure microbial culture. This is the first study to report 6:2 FTSA biotransformation in aerobic and anaerobic sediment. 6:2 FTSA was rapidly biotransformed in aerobic river sediment with a half-life less than 5 d. Major stable transformation products observed after 90 d included 5:3 Acid [F(CF2)5CH2CH2COOH), 16 mol%), PFPeA [F(CF2)4COOH, 21 mol%] and PFHxA (F(CF2)5COOH, 20 mol%). 6:2 fluorotelomer alcohol [6:2 FTOH, F(CF2)6CH2CH2OH] was readily biotransfomed whereas 6:2 FTSA biotransformation did not occur in anaerobic sediment over 100 d, indicating that the enzymatic desulfonation step limited 6:2 FTSA biotransformation in anaerobic sediment. These results suggest that 6:2 FTSA related products, after release to the aerobic environment, is likely to biodegrade forming 5:3 Acid, PFPeA and PFHxA. This study also indicates that 6:2 FTSA formed from its aforementioned precursors may be persistent in the anaerobic environment after their potential release. This work provides insight to understanding the fate and environmental loading of AFFF-related products and their major transformation products in the environment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Determination of Biotransformation Products of Platinum Drugs in Rat and Human Urine

    PubMed Central

    Tang, Xia; Hayes, II, Jerry W.; Schroder, Louis; Cacini, William; Dorsey, John; Elder, R. C.

    1997-01-01

    Cisplatin is an extremely effective cancer chemotherapeutic agent, but its use is often accompanied by toxicity. Second generation drugs such as carboplatin are becoming more widely used because of reduced toxicity. Since biotransformation products have been implicated in the toxic responses, we have begun to investigate the reactions of cisplatin and carboplatin with potential biological ligands. Reaction products were characterized using HPLC with inductively coupled plasma - mass spectrometry (HPLC-ICP-MS), 1H and 13C NMR and fast atom bombardment - mass spectrometry (FAB-MS). Three Pt-creatinine complexes, cis-[Pt(NH3)2Cl(Creat)]+, cis-[Pt(NH3)2(H2O)(Creat)]2+ and cis-[Pt(NH3)2(Creat)2]2+, were synthesized and the platinum was shown to coordinate to the ring nitrogen, N(3). Human urine samples from patients on cisplatin chemotherapy were shown to contain cisplatin, its hydrolysis product and biotransformation products containing Pt-creatinine, Pt-urea and Pt-uric acid complexes. Urine from carboplatin patients shows fewer biotransformation products. Studies with control and diabetic (protected against cisplatin toxicity) rats showed systematic differences in the biotransformation products formed on administration of cisplatin. PMID:18475775

  9. Kinetic analysis and modelling of enzymatic (R)-phenylacetylcarbinol batch biotransformation process.

    PubMed

    Leksawasdi, Noppol; Chow, Yvonne Y S; Breuer, Michael; Hauer, Bernhard; Rosche, Bettina; Rogers, Peter L

    2004-07-15

    Initial rate and biotransformation studies were applied to refine and validate a mathematical model for enzymatic (R)-phenylacetylcarbinol (PAC) production from pyruvate and benzaldehyde using Candida utilis pyruvate decarboxylase (PDC). The rate of PAC formation was directly proportional to the enzyme activity level up to 5.0 U ml-1 carboligase. Michaelis-Menten kinetics were determined for the effect of pyruvate concentration on the reaction rate. The effect of benzaldehyde followed the sigmoidal shape of the Monod-Wyman-Changeux (MWC) model. The biotransformation model, which also included a term for PDC inactivation by benzaldehyde, was used to determine the overall rate constants for the formation of PAC, acetaldehyde, and acetoin. These values were determined from data for three batch biotransformations performed over a range of initial concentrations (viz. 50-150 mM benzaldehyde, 60-180 mM pyruvate, 1.1-3.4 U ml-1 enzyme activity). The finalized model was then used to predict a batch biotransformation profile at 120/100 mM initial pyruvate/benzaldehyde (initial enzyme activity 3.0 U ml-1). The simulated kinetics gave acceptable fitting (R2 = 0.9963) to the time courses of these latter experimental data for substrates pyruvate and benzaldehyde, product PAC, by-products acetaldehyde and acetoin, as well as enzyme activity level.

  10. Scale-up of biotransformation process in stirred tank reactor using dual impeller bioreactor.

    PubMed

    Shukla, V B.; Parasu Veera, U; Kulkarni, P R.; Pandit, A B.

    2001-07-01

    The gas-liquid mass transfer coefficient K(L)a in the fermenter is a strong function of mode of energy dissipation and physico-chemical properties of the liquid media. A combination of disc turbine (DT) and pitched blade turbine down flow (PTD) impellers has been tested in laboratory bioreactor for gas hold-up and gas-liquid mass transfer performance for the growth and biotransformation medium for an yeast isolate VS1 capable of biotransforming benzaldehyde to L-phenyl acetyl carbinol (L-PAC) and compared with those in water.Correlations have been developed for the prediction of the fractional gas hold-up and gas-liquid mass transfer coefficient for the above media. The mass transfer coefficient and respiration rate have been determined in the shake flask for the growth as well as for biotransformation medium. These results, then have been used to optimize the operating parameters (impeller speed and aeration) for growth and biotransformation in a laboratory bioreactor. The comparison of cell mass production and L-PAC production in the bioreactor has been done with that obtained in shake flask studies.

  11. Flavonoids biotransformation by bacterial non-heme dioxygenases, biphenyl and naphthalene dioxygenase.

    PubMed

    Seo, Jiyoung; Kang, Su-Il; Kim, Mihyang; Han, Jaehong; Hur, Hor-Gil

    2011-07-01

    This review details recent progresses in the flavonoid biotransformation by bacterial non-heme dioxygenases, biphenyl dioxygenase (BDO), and naphthalene dioxygenase (NDO), which can initially activate biphenyl and naphthalene with insertion of dioxygen in stereospecfic and regiospecific manners. Flavone, isoflavone, flavanone, and isoflavanol were biotransformed by BDO from Pseudomonas pseudoalcaligenes KF707 and NDO from Pseudomonas sp. strain NCIB9816-4, respectively. In general, BDO showed wide range of substrate spectrum and produced the oxidized products, whereas NDO only metabolized flat two-dimensional substrates of flavone and isoflavone. Furthermore, biotransformation of B-ring skewed substrates, flavanone and isoflavanol, by BDO produced the epoxide products, instead of dihydrodiols. These results support the idea that substrate-driven reactivity alteration of the Fe-oxo active species may occur in the active site of non-heme dioxygenases. The study of flavonoid biotransformation by structurally-well defined BDO and NDO will provide the substrate structure and reactivity relationships and eventually establish the production of non-plant-originated flavonoids by means of microbial biotechnology.

  12. Modification and evolution of Gluconobacter oxydans for enhanced growth and biotransformation capabilities at low glucose concentration.

    PubMed

    Zhu, Kun; Lu, Leifang; Wei, Liujing; Wei, Dongzhi; Imanaka, Tadayuki; Hua, Qiang

    2011-09-01

    Gluconobacter oxydans is widely used in several biotechnological applications, where sorbitol or mannitol is commonly used as carbon source at high concentration. In this study, a membrane-bound glucose dehydrogenase-deficient strain (GDHK) was constructed to eliminate growth problems on glucose caused by direct oxidation of glucose in the medium. To achieve improved growth properties for the GDHK strain on glucose, a laboratory adaptive evolution experiment was performed with glucose as the sole carbon source. Results indicated evident, albeit modest, improvements in cell growth after a 50-day (about 430 generations) experimental evolution on glucose. The maximum specific growth rate and biomass yield of the resulting GDHE50 strain were increased around 1.35- to 1.4-fold compared with those of the GDHK strain. Meanwhile, two types of biotransformation reactions using resting cells of G. oxydans were investigated. Significant elevations in biotransformation performance of the GHDE50 strain were observed in comparison with that of the wild-type strain. In addition, resting cells of the GDHE50 strain grown on a relatively low concentration of glucose (10 g/l) could catalyze the biotransformation of glycerol to dihydroxyacetone and ethylene glycol to glycolic acid as efficient as the wild-type G. oxydans cultured on higher concentration of sorbitol or other carbon sources. These results suggest very favorable prospects of using glucose to lower production cost in many important industrial biocatalysis and biotransformation processes.

  13. Biotransformation of Natural and Synthetic Isoflavonoids by Two Recombinant Microbial Enzymes

    PubMed Central

    Seeger, Michael; González, Myriam; Cámara, Beatriz; Muñoz, Liliana; Ponce, Emilio; Mejías, Lorenzo; Mascayano, Carolina; Vásquez, Yesseny; Sepúlveda-Boza, Silvia

    2003-01-01

    Isolation and synthesis of isoflavonoids has become a frequent endeavor, due to their interesting biological activities. The introduction of hydroxyl groups into isoflavonoids by the use of enzymes represents an attractive alternative to conventional chemical synthesis. In this study, the capabilities of biphenyl-2,3-dioxygenase (BphA) and biphenyl-2,3-dihydrodiol 2,3-dehydrogenase (BphB) of Burkholderia sp. strain LB400 to biotransform 14 isoflavonoids synthesized in the laboratory were investigated by using recombinant Escherichia coli strains containing plasmid vectors expressing the bphA1A2A3A4 or bphA1A2A3A4B genes of strain LB400. The use of BphA and BphB allowed us to biotransform 7-hydroxy-8-methylisoflavone and 7-hydroxyisoflavone into 7,2′,3′-trihydroxy-8-methylisoflavone and 7,3′,4′-trihydroxyisoflavone, respectively. The compound 2′-fluoro-7-hydroxy-8-methylisoflavone was dihydroxylated by BphA at ortho-fluorinated and meta positions of ring B, with concomitant dehalogenation leading to 7,2′,3′,-trihydroxy-8-methylisoflavone. Daidzein (7,4′-dihydroxyisoflavone) was biotransformed by BphA, generating 7,2′,4′-trihydroxyisoflavone after dehydration. Biotransformation products were analyzed by gas chromatography-mass spectrometry and nuclear magnetic resonance techniques. PMID:12957885

  14. Developmental and genetic modulation of arsenic biotransformation: A gene by environment interaction?

    SciTech Connect

    Meza, Mercedes; Gandolfi, A. Jay; Klimecki, Walter T.

    2007-08-01

    The complexity of arsenic toxicology has confounded the identification of specific pathways of disease causation. One focal point of arsenic research is aimed at fully characterizing arsenic biotransformation in humans, a process that appears to be quite variable, producing a mixture of several arsenic species with greatly differing toxic potencies. In an effort to characterize genetic determinants of variability in arsenic biotransformation, a genetic association study of 135 subjects in western Sonora, Mexico was performed by testing 23 polymorphic sites in three arsenic biotransformation candidate genes. One gene, arsenic 3 methyltransferase (AS3MT), was strongly associated with the ratio of urinary dimethylarsinic acid to monomethylarsonic acid (D/M) in children (7-11 years) but not in adults (18-79 years). Subsequent analyses revealed that the high D/M values associated with variant AS3MT alleles were primarily due to lower levels of monomethylarsonic acid as percent of total urinary arsenic (%MMA5). In light of several reports of arsenic-induced disease being associated with relatively high %MMA5 levels, these findings raise the possibility that variant AS3MT individuals may suffer less risk from arsenic exposure than non-variant individuals. These analyses also provide evidence that, in this population, regardless of AS3MT variant status, children tend to have lower %MMA5 values than adults, suggesting that the global developmental regulation of arsenic biotransformation may interact with genetic variants in metabolic genes to result in novel genetic effects such as those in this report.

  15. Employment as a Social Determinant of Health: A Systematic Review of Longitudinal Studies Exploring the Relationship between Employment Status and Physical Health

    ERIC Educational Resources Information Center

    Hergenrather, Kenneth C.; Zeglin, Robert J.; McGuire-Kuletz, Maureen; Rhodes, Scott D.

    2015-01-01

    Purpose: To explore employment as a social determinant of health through examining the relationship between employment status and physical health. Method: The authors explored the causal relationship between employment status and physical health through conducting a systematic review of 22 longitudinal studies conducted in Finland, France, the…

  16. Employment as a Social Determinant of Health: A Systematic Review of Longitudinal Studies Exploring the Relationship between Employment Status and Physical Health

    ERIC Educational Resources Information Center

    Hergenrather, Kenneth C.; Zeglin, Robert J.; McGuire-Kuletz, Maureen; Rhodes, Scott D.

    2015-01-01

    Purpose: To explore employment as a social determinant of health through examining the relationship between employment status and physical health. Method: The authors explored the causal relationship between employment status and physical health through conducting a systematic review of 22 longitudinal studies conducted in Finland, France, the…

  17. Biotransformation for L-ephedrine production.

    PubMed

    Rogers, P L; Shin, H S; Wang, B

    1997-01-01

    L-ephedrine is widely used in pharmaceutical preparations as a decongestant and anti-asthmatic compound. One of the key intermediates in its production is L-phenylacetylcarbinol (L-PAC) which can be obtained either from plants (Ephedra sp.), chemical synthesis involving resolution of a racemic mixture, or by biotransformation of benzaldehyde using various yeasts. In the present review, recent significant improvements in the microbial biotransformation are assessed for both fed-batch and continuous processes using free and immobilised yeasts. From previous fed-batch culture data, maximal levels of L-PAC of 10-12 gl-1 were reported with yields of 55-60% theoretical based on benzaldehyde. However, recently concentrations of more than 22 gl-1 have been obtained using a wild-type strain of Candida utilis. This has been achieved through optimal control of yeast metabolism (via microprocessor control of the respiratory quotient, RQ) in order to enhance substrate pyruvate production and induce pyruvate decarboxylase (PDC) activity. Processes involving purified PDC have also been evaluated and it has been demonstrated that L-PAC levels up to 28 gl-1 can be obtained with yields of 90-95% theoretical based on the benzaldehyde added. In the review the advantages and disadvantages of the various strategies for the microbial and enzymatic production of L-PAC are compared. In view of the increasing interest in microbial biotransformations, L-PAC production provides an interesting example of enhancement through on-line control of a process involving both toxic substrate (benzaldehyde) and end-product (L-PAC, benzyl alcohol) inhibition.

  18. Biotransformation of inorganic arsenic in a marine herbivorous fish Siganus fuscescens after dietborne exposure.

    PubMed

    Zhang, Wei; Chen, Lizhao; Zhou, Yanyan; Wu, Yun; Zhang, Li

    2016-03-01

    Arsenic (As) is well known to be biodiminished along marine food chains. The marine herbivorous fish at a lower trophic level are expected to accumulate more As. However, little is known about how marine herbivorous fish biotransform the potential high As bioaccumulation. Therefore, the present study quantified the biotransformation of two inorganic As species (As(III) and As(V)) in a marine herbivorous fish Siganus fuscescens following dietborne exposure. The fish were fed on As contaminated artificial diets at nominal concentrations of 400 and 1500 μg As(III) or As(V) g(-1) (dry weight) for 21 d and 42 d. After exposure, As concentrations in intestine, liver, and muscle tissues of rabbitfish increased significantly and were proportional to the inorganic As exposure concentrations. The present study demonstrated that both inorganic As(III) and As(V) in the dietborne phases were able to be biotransformed to the less toxic arsenobetaine (AsB) (63.3-91.3% in liver; 79.0%-95.2% in muscle). The processes of As biotransformation in rabbitfish could include oxidation of As(III) to As(V), reduction of As(V) to As(III), methylation to monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA), and subsequent conversion to AsB. These results also demonstrated that AsB synthesis processes were diverse facing different inorganic As species in different tissues. In summary, the present study elucidated that marine herbivorous fish had high ability to biotransform inorganic As to the organic forms (mainly AsB), resulting in high As bioaccumulation. Therefore, marine herbivorous fish could detoxify inorganic As in the natural environment.

  19. Employing Two Factor Authentication Mechanisms: A Case Study

    ERIC Educational Resources Information Center

    Lawrence, Cameron; Fulton, Eric; Evans, Gerald; Firth, David

    2014-01-01

    This case study examines the life of a digital native who has her online accounts hacked, passwords reset, and is locked out of important online resources including her university email account and Facebook. Part one of the case study examines how the hack was perpetrated and the fallout of losing control of one's digital identity. Part two of the…

  20. Biotransformation of naphthalene and diaryl ethers by green microalgae.

    PubMed

    Todd, Sarah J; Cain, Ronald B; Schmidt, Stefan

    2002-01-01

    The role of green microalgae in the biotransformation of naphthalene (a polycyclic aromatic hydrocarbon) and diaryl ethers was investigated using axenic cultures of Chlorella vulgaris and two environmental isolates, Scenedesmus SI1 and Ankistrodesmus SI2. Biotransformation experiments with dense cell cultures showed that these three green algae transformed toxic xenobiotics to more polar metabolites. Chlorella vulgaris metabolized naphthalene to 1-naphthol (0.36-0.65%). Ankistrodesmus SI2 biotransformed dibenzofuran to six metabolites (total over 7%), three of which (possibly four) were identified as monohydroxylated dibenzofurans, the remaining two may be dihydroxylated derivatives. Scenedesmus SI1 biotransformed dibenzo-p-dioxin to three metabolites, one of which was tentatively identified as 2-hydroxydibenzo-p-dioxin (approximately 3.8%), the remainder may be dihydroxylated derivatives. This is the first time that the biotransformation of diaryl ethers by green microalgae has been investigated.

  1. The production of fine chemicals by biotransformations.

    PubMed

    Straathof, Adrie J J; Panke, Sven; Schmid, Andreas

    2002-12-01

    Today, biocatalysis is a standard technology for the production of chemicals. An analysis of 134 industrial biotransformations reveals that hydrolases (44%) and redox biocatalysts (30%) are the most prominent categories. Most products are chiral (89%) and are used as fine chemicals. In the chemical industry, successful product developments involve on average a yield of 78%, a volumetric productivity of 15.5 g/(L.h) and a final product concentration of 108 g/L. By contrast, the pharmaceutical industry focuses on time-to-market. The implications of this for future research and development on biocatalysis are discussed.

  2. Biocatalysis and biotransformation of resveratrol in microorganisms.

    PubMed

    Mei, Yan-Zhen; Liu, Ruo-Xue; Wang, Dong-Peng; Wang, Xia; Dai, Chuan-Chao

    2015-01-01

    Resveratrol, a major stilbene phytoalexin, is a valuable polyphenol that has been recognized for its benefits to human health. Resveratrol has antioxidant and antitumor effects and promotes longevity. It is used in medicine, health care products, cosmetics, and other industries. Therefore, a sustainable source for resveratrol production is required. This review describes the metabolic engineering of microorganisms, the biotransformation and biosynthesis of endophytes and the oxidation or degradation of resveratrol. We compare various available methods for resveratrol production, and summarize the practical challenges facing the microbial production of resveratrol. The future research direction for resveratrol is also discussed.

  3. Biotransformation of trans-1-chloro-3,3,3-trifluoropropene (trans-HCFO-1233zd)

    SciTech Connect

    Schmidt, Tobias; Bertermann, Rüdiger; Rusch, George M.; Tveit, Ann; Dekant, Wolfgang

    2013-05-01

    trans-1-Chloro-3,3,3-trifluoropropene (trans-HCFO-1233zd) is a novel foam blowing and precision cleaning agent with a very low impact for global warming and ozone depletion. trans-HCFO-1233zd also has a low potential for toxicity in rodents and is negative in genotoxicity testing. The biotransformation of trans-HCFO-1233zd and kinetics of metabolite excretion with urine were assessed in vitro and in animals after inhalation exposures. For in vitro characterization, liver microsomes from rats, rabbits and humans were incubated with trans-HCFO-1233zd. Male Sprague Dawley rats and female New Zealand White rabbits were exposed to 2,000, 5,000 and 10,000 ppm for 6 h and urine was collected for 48 h after the end of the exposure. Study specimens were analyzed for metabolites using {sup 19}F NMR, LC-MS/MS and GC/MS. S-(3,3,3-trifluoro-trans-propenyl)-glutathione was identified as predominant metabolite of trans-HCFO-1233zd in all microsomal incubation experiments in the presence of glutathione. Products of the oxidative biotransformation of trans-HCFO-1233zd were only minor metabolites when glutathione was present. In rats, both 3,3,3-trifluorolactic acid and N-acetyl-(3,3,3-trifluoro-trans-propenyl)-L-cysteine were observed as major urinary metabolites. 3,3,3-Trifluorolactic acid was not detected in the urine of rabbits. Quantitation showed rapid excretion of both metabolites in both species (t{sub 1/2} < 6 h) and the extent of biotransformation of trans-HCFO-1233zd was determined as approximately 0.01% of received dose in rabbits and approximately 0.002% in rats. trans-HCFO-1233zd undergoes both oxidative biotransformation and glutathione conjugation at very low rates. The low extent of biotransformation and the rapid excretion of metabolites formed are consistent with the very low potential for toxicity of trans-HCFO-1233zd in mammals. - Highlights: ► No lethality and clinical signs were observed. ► Glutathione S-transferase and cytochrome P-450 dependent

  4. Bioaccumulation, biotransformation, and metabolite formation of fipronil and chiral legacy pesticides in rainbow trout.

    PubMed

    Konwick, Brad J; Garrison, Arthur W; Black, Marsha C; Avants, Jimmy K; Fisk, Aaron T

    2006-05-01

    To assess the fate of current-use pesticides, it is important to understand their bioaccumulation and biotransformation by aquatic biota. We examined the dietary accumulation and enantioselective biotransformation of the chiral current-use pesticide fipronil, along with a mixture of selected chiral [alpha-hexachlorocyclohexane (alpha-HCH), heptachlor epoxide (HEPX), polychlorinated biphenyls (PCBs) 84, 132, 174, o,p'-DDT, and o,p'-DDD] and nonchiral (p,p'-DDT, p,p'-DDD) organochlorine compounds in juvenile rainbow trout (Oncorhynchus mykiss). Fish rapidly accumulated all compounds, as measured in the carcass (whole body minus liver and GI tract) during the 32 d uptake phase, which was followed by varying elimination rates of the chemicals (half-lives (t1/2s) ranging from 0.6 d for fipronil to 77.0 d for PCB 174) during the 96 d depuration period. No biotransformation was observed for alpha-HCH, HEPX, PCB 174, o,p'-DDT, or o,p'-DDD based on consistent enantiomeric fractions (EFs) in the fish and their t1/2s falling on a log K(ow)--log t1/2 relationship established for recalcitrant contaminants in fish. p,p'-DDT and PCBs 84 and 132 were biotransformed based on the former's t1/2 position below the log K(ow)--log t1/2 relationship, and the PCBs change in EF. Fipronil was rapidly biotransformed, based on a change in EF, a t1/2 that fell below the log K(ow)--log t1//2 relationship, which accounted for 88% of its elimination, and the rapid formation of fipronil sulfone, a known metabolite. Fipronil sulfone was found to persist longer (t1/2 approximately 2 d) than its parent compound fipronil (t1/2 approximately 0.6 d) and needs to be considered in fate studies of fipronil. This research demonstrates the utilities of the log K(ow)--log t1/2 relationship as a mechanistic tool for quantifying biotransformation and of chiral analysis to measure biotransformation in fish.

  5. Sex differences in hepatic and intestinal contributions to nevirapine biotransformation in rats.

    PubMed

    Pinheiro, P F; Marinho, A T; Antunes, A M M; Marques, M M; Pereira, S A; Miranda, J P

    2015-05-25

    The understanding of the intestine contribution to drug biotransformation improved significantly in recent years. However, the sources of inter-individual variability in intestinal drug biotransformation, namely sex-differences, are still elusive. Nevirapine (NVP) is an orally taken anti-HIV drug associated with severe idiosyncratic reactions elicited by toxic metabolites, with women at increased risk. As such, NVP is a good model to assess sex-dimorphic metabolism. The aim of this study was to perform a comparative profiling of NVP biotransformation in rat intestine and liver and evaluate whether or not it is organ- and sex-dependent. Therefore, nevirapine-containing solutions were perfused through the intestine, in a specially designed chamber, or incubated with liver slices, from male and female Wistar rats. The levels of NVP and its Phase I metabolites were quantified by HPLC-UV. Liver incubation experiments yielded the metabolites 2-, 3-, 8-, and 12-OH-NVP, being 12-OH-NVP and 2-OH-NVP the major metabolites in males and females, respectively. Inter-sex differences in the metabolic profile were also detected in the intestine perfusion experiments. Herein, the metabolites 3- and 12-OH-NVP were only found in male rats, whereas 2-OH-NVP levels were higher in females, both in extraluminal (p<0.01) and intraluminal media. The metabolite 8-OH-NVP was not detected in the intraluminal media from either males or females. In this study, important inter-sex differences were detected in both organs, providing further clues to the sex-dimorphic profile of NVP toxicity. Moreover, an extra-hepatic contribution to NVP biotransformation was observed, strengthening the relevance of the intestinal contribution in the biotransformation of orally taken-drugs.

  6. Polymorphisms of genes involved in polycyclic aromatic hydrocarbons’ biotransformation and atherosclerosis

    PubMed Central

    Marinković, Natalija; Pašalić, Daria; Potočki, Slavica

    2013-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are among the most prevalent environmental pollutants and result from the incomplete combustion of hydrocarbons (coal and gasoline, fossil fuel combustion, byproducts of industrial processing, natural emission, cigarette smoking, etc.). The first phase of xenobiotic biotransformation in the PAH metabolism includes activities of cytochrome P450 from the CYP1 family and microsomal epoxide hydrolase. The products of this biotransformation are reactive oxygen species that are transformed in the second phase through the formation of conjugates with glutathione, glucuronate or sulphates. PAH exposure may lead to PAH-DNA adduct formation or induce an inflammatory atherosclerotic plaque phenotype. Several genetic polymorphisms of genes encoded for enzymes involved in PAH biotransformation have been proven to lead to the development of diseases. Enzyme CYP P450 1A1, which is encoded by the CYP1A1 gene, is vital in the monooxygenation of lipofilic substrates, while GSTM1 and GSTT1 are the most abundant isophorms that conjugate and neutralize oxygen products. Some single nucleotide polymorphisms of the CYP1A1 gene as well as the deletion polymorphisms of GSTT1 and GSTM1 may alter the final specific cellular inflammatory respond. Occupational exposure or conditions from the living environment can contribute to the production of PAH metabolites with adverse effects on human health. The aim of this study was to obtain data on biotransformation and atherosclerosis, as well as data on the gene polymorphisms involved in biotransformation, in order to better study gene expression and further elucidate the interaction between genes and the environment. PMID:24266295

  7. Barriers to Employment Among Social Security Disability Insurance Beneficiaries in the Mental Health Treatment Study.

    PubMed

    Milfort, Roline; Bond, Gary R; McGurk, Susan R; Drake, Robert E

    2015-12-01

    This study examined barriers to employment among Social Security Disability Insurance (SSDI) beneficiaries who received comprehensive vocational and mental health services but were not successful in returning to work. This study examined barriers to employment among 430 SSDI beneficiaries with mental disorders who received evidence-based vocational and mental health services for two years but worked less than one month or not at all. Comprehensive care teams, which included employment specialists, made consensus judgments for each participant, identifying the top three barriers to employment from a checklist of 14 common barriers. Teams most frequently identified three barriers to employment: poorly controlled symptoms of mental illness (55%), nonengagement in supported employment (44%), and poorly controlled general medical problems (33%). Other factors were identified much less frequently. Some SSDI beneficiaries, despite having access to comprehensive services, continued to experience psychiatric impairments, difficulty engaging in vocational services, and general medical problems that limited their success in employment.

  8. Predicting Employment in the Mental Health Treatment Study: Do Client Factors Matter?

    PubMed

    Metcalfe, Justin D; Drake, Robert E; Bond, Gary R

    2017-05-01

    For people with psychiatric disabilities, demographic characteristics and measures of clinical status are often used to allocate scarce employment services. This study examined a battery of potential client predictors of competitive employment, testing the hypothesis that evidence-based supported employment would mitigate the negative effects of poor work history, uncontrolled symptoms, substance abuse, and other client factors. In a secondary analysis of 2055 unemployed Social Security Disability Insurance beneficiaries with schizophrenia or affective disorders, we examined 20 baseline client factors as predictors of competitive employment. The analysis used logistic regression to identify significant client predictors and then examined interactions between significant predictors and receipt of evidence-based supported employment. Work history was a strong predictor of employment, and other client measures (fewer years on disability rolls, Hispanic ethnicity, and fewer physical health problems) were modestly predictive. Evidence-based supported employment mitigated negative client factors, including poor work history. Participants with a poor work history benefitted from supported employment even more than those with a recent work experience. Evidence-based supported employment helps people with serious mental illness, especially those with poor job histories, to obtain competitive employment. Factors commonly considered barriers to employment, such as diagnosis, substance use, hospitalization history, and misconceptions about disability benefits, often have little or no impact on competitive employment outcomes.

  9. Employment Experiences of Deaf College Graduates: An Interview Study.

    ERIC Educational Resources Information Center

    Foster, Susan B.

    1987-01-01

    The qualitative study examined characteristics of 25 deaf graduates of the Rochester Institute of Technology. Findings are discussed for finding a job, learning the job, communication at work, relationships at work, expectations for the future, discrimination in the workplace, reasons for leaving the job, and strategies for managing difficult work…

  10. Employment after Vision Loss: Results of a Collective Case Study.

    ERIC Educational Resources Information Center

    Crudden, Adele

    2002-01-01

    A collective case study approach was used to examine factors that influence the job retention of persons with vision loss. Computer technology was found to be a major positive influence and print access and technology were a source of stress for most participants (n=10). (Contains 7 references.) (Author/CR)

  11. Congenital Adrenal Hyperplasia: Classification of Studies Employing Psychological Endpoints

    PubMed Central

    Stout, Stephanie A.; Litvak, Margarita; Robbins, Natashia M.; Sandberg, David E.

    2010-01-01

    Psychological outcomes in persons with congenital adrenal hyperplasia (CAH) have received substantial attention. The objectives of this paper were to (1) catalog psychological endpoints assessed in CAH outcome studies and (2) classify the conceptual/theoretical model shaping the research design and interpretation of CAH-related psychological effects. A total of 98 original research studies, published between 1955 and 2009, were categorized based on psychological endpoints examined as well as the research design and conceptual model guiding analysis and interpretation of data. The majority of studies (68%) investigated endpoints related to psychosexual differentiation. The preponderance of studies (76%) examined a direct relationship (i.e., inferring causality) between prenatal androgen exposure and psychological outcomes. Findings are discussed in relation to the observed imbalance between theoretical interest in the role of prenatal androgens in shaping psychosexual differentiation and a broader conceptual model that examines the role of other potential factors in mediating or moderating the influence of CAH pathophysiology on psychological outcomes in both affected females and males. The latter approach offers to identify factors amenable to clinical intervention that enhance both health and quality of life outcomes in CAH as well as other disorders of sex development. PMID:20976294

  12. Congenital adrenal hyperplasia: classification of studies employing psychological endpoints.

    PubMed

    Stout, Stephanie A; Litvak, Margarita; Robbins, Natashia M; Sandberg, David E

    2010-01-01

    Psychological outcomes in persons with congenital adrenal hyperplasia (CAH) have received substantial attention. The objectives of this paper were to (1) catalog psychological endpoints assessed in CAH outcome studies and (2) classify the conceptual/theoretical model shaping the research design and interpretation of CAH-related psychological effects. A total of 98 original research studies, published between 1955 and 2009, were categorized based on psychological endpoints examined as well as the research design and conceptual model guiding analysis and interpretation of data. The majority of studies (68%) investigated endpoints related to psychosexual differentiation. The preponderance of studies (76%) examined a direct relationship (i.e., inferring causality) between prenatal androgen exposure and psychological outcomes. Findings are discussed in relation to the observed imbalance between theoretical interest in the role of prenatal androgens in shaping psychosexual differentiation and a broader conceptual model that examines the role of other potential factors in mediating or moderating the influence of CAH pathophysiology on psychological outcomes in both affected females and males. The latter approach offers to identify factors amenable to clinical intervention that enhance both health and quality of life outcomes in CAH as well as other disorders of sex development.

  13. Employment after Vision Loss: Results of a Collective Case Study.

    ERIC Educational Resources Information Center

    Crudden, Adele

    2002-01-01

    A collective case study approach was used to examine factors that influence the job retention of persons with vision loss. Computer technology was found to be a major positive influence and print access and technology were a source of stress for most participants (n=10). (Contains 7 references.) (Author/CR)

  14. Aircraft systems design studies employing advanced transport technologies

    NASA Technical Reports Server (NTRS)

    Downie, B.; Pearce, C.; Quartero, C.; Taylor, A.

    1972-01-01

    System and design integration studies are presented to define and assess the application of the advanced technology most likely to result in a superior next generation, high subsonic/sonic conventional takeoff and landing transport aircraft system. It is concluded that the new technologies can be directed toward the achievement of improved economy and performance. These benefits may be used to compensate for the penalties associated with reduced noise requirements anticipated to make future aircraft ecologically acceptable.

  15. Factors associated with persons with disability employment in India: a cross-sectional study.

    PubMed

    Naraharisetti, Ramya; Castro, Marcia C

    2016-10-07

    Over twenty million persons with disability in India are increasingly being offered poverty alleviation strategies, including employment programs. This study employs a spatial analytic approach to identify correlates of employment among persons with disability in India, considering sight, speech, hearing, movement, and mental disabilities. Based on 2001 Census data, this study utilizes linear regression and spatial autoregressive models to identify factors associated with the proportion employed among persons with disability at the district level. Models stratified by rural and urban areas were also considered. Spatial autoregressive models revealed that different factors contribute to employment of persons with disability in rural and urban areas. In rural areas, having mental disability decreased the likelihood of employment, while being female and having movement, or sight impairment (compared to other disabilities) increased the likelihood of employment. In urban areas, being female and illiterate decreased the likelihood of employment but having sight, mental and movement impairment (compared to other disabilities) increased the likelihood of employment. Poverty alleviation programs designed for persons with disability in India should account for differences in employment by disability types and should be spatially targeted. Since persons with disability in rural and urban areas have different factors contributing to their employment, it is vital that government and service-planning organizations account for these differences when creating programs aimed at livelihood development.

  16. Aerobic Biotransformation of Fluorotelomer Thioether Amido Sulfonate (Lodyne) in AFFF-Amended Microcosms.

    PubMed

    Harding-Marjanovic, Katie C; Houtz, Erika F; Yi, Shan; Field, Jennifer A; Sedlak, David L; Alvarez-Cohen, Lisa

    2015-07-07

    The aerobic biotransformation pathways of 4:2, 6:2, and 8:2 fluorotelomer thioether amido sulfonate (FtTAoS) were characterized by determining the fate of the compounds in soil and medium microcosms amended with an aqueous film-forming foam (AFFF) solution. The biotransformation of FtTAoS occurred in live microcosms over approximately 40 days and produced 4:2, 6:2, and 8:2 fluorotelomer sulfonate (FtS), 6:2 fluorotelomer unsaturated carboxylic acid (FtUCA), 5:3 fluorotelomer carboxylic acid (FtCA), and C4 to C8 perfluorinated carboxylic acids (PFCAs). Two biotransformation products corresponding to singly and doubly oxygenated forms of 6:2 FtTAoS were also identified through high resolution mass spectrometry (MS) analysis and liquid chromatography tandem-MS. An oxidative assay was used to indirectly quantify the total concentration of polyfluorinated compounds and check the mass balance. The assay produced near complete mass recovery of FtTAoS after biotransformation, with 10% (mol/mol) of the amended FtTAoS accounted for in FtS, FtCA, and PFCA products. The transformation rates of identified products appear to be slow relative to FtTAoS, indicating that some intermediates may persist in the environment. This study confirms some of the sources of FtS and PFCAs in groundwater and soil at AFFF-impacted sites and suggests that fluorinated intermediates that are not routinely measured during the biotransformation of PFASs may accumulate.

  17. Somatic and gastrointestinal in vivo biotransformation rates of hydrophobic chemicals in fish.

    PubMed

    Lo, Justin C; Campbell, David A; Kennedy, Christopher J; Gobas, Frank A P C

    2015-10-01

    To improve current bioaccumulation assessment methods, a methodology is developed, applied, and investigated for measuring in vivo biotransformation rates of hydrophobic organic substances in the body (soma) and gastrointestinal tract of the fish. The method resembles the Organisation for Economic Co-operation and Development (OECD) 305 dietary bioaccumulation test but includes reference chemicals to determine both somatic and gastrointestinal biotransformation rates of test chemicals. Somatic biotransformation rate constants for the test chemicals ranged between 0 d(-1) and 0.38 (standard error [SE] 0.03)/d(-1) . Gastrointestinal biotransformation rate constants varied from 0 d(-1) to 46 (SE 7) d(-1) . Gastrointestinal biotransformation contributed more to the overall biotransformation in fish than somatic biotransformation for all test substances but 1. Results suggest that biomagnification tests can reveal the full extent of biotransformation in fish. The common presumption that the liver is the main site of biotransformation may not apply to many substances exposed through the diet. The results suggest that the application of quantitative structure-activity relationships (QSARs) for somatic biotransformation rates and hepatic in vitro models to assess the effect of biotransformation on bioaccumulation can underestimate biotransformation rates and overestimate the biomagnification potential of chemicals that are biotransformed in the gastrointestinal tract. With some modifications, the OECD 305 test can generate somatic and gastrointestinal biotransformation data to develop biotransformation QSARs and test in vitro-in vivo biotransformation extrapolation methods.

  18. An Empirical Study of Self-Perceived Employability: Improving the Prospects for Student Employment Success in an Uncertain Environment

    ERIC Educational Resources Information Center

    Qenani, Eivis; MacDougall, Neal; Sexton, Carol

    2014-01-01

    Employability of graduates has taken more prominence in recent years due to the bleak economic situation, the impact of student debt, and an increasingly competitive global labor market. Given the substantial individual and public investment made in higher education, it is particularly important that graduates are employable upon graduation. The…

  19. An Empirical Study of Self-Perceived Employability: Improving the Prospects for Student Employment Success in an Uncertain Environment

    ERIC Educational Resources Information Center

    Qenani, Eivis; MacDougall, Neal; Sexton, Carol

    2014-01-01

    Employability of graduates has taken more prominence in recent years due to the bleak economic situation, the impact of student debt, and an increasingly competitive global labor market. Given the substantial individual and public investment made in higher education, it is particularly important that graduates are employable upon graduation. The…

  20. Family employment and child socioemotional behaviour: longitudinal findings from the UK Millennium Cohort Study.

    PubMed

    Hope, Steven; Pearce, Anna; Whitehead, Margaret; Law, Catherine

    2014-10-01

    Levels of paid employment in two parent and lone parent families have increased in the UK but evidence of its impact on child socioemotional behaviour is limited and inconsistent. We conducted a longitudinal analysis using the first four sweeps of the Millennium Cohort Study (9 months, 3 years, 5 years and 7 years) to investigate the influence of family employment trajectories in the early years on socioemotional behaviour at 7 years, unadjusted and adjusted for covariates. In addition, mothers' employment was investigated separately. Children from families where no parent was employed for one or more sweeps were at a greater risk of socioemotional problem behaviour compared with those where a parent was continuously employed, even after adjustment for covariates. Children of mothers who were non-employed for one or more sweeps were at greater risk of problem behaviour compared with mothers who were employed at all sweeps. Adjustment for covariates fully attenuated the excess risk for children whose mothers had moved into employment by the time they were 7 years. In contrast, the elevated risk associated with continuous non-employment and a single transition out of employment was attenuated after adjustment for early covariates, fathers' employment, household income and mothers' psychological distress at 7 years, but remained significant. Family and mothers' employment were associated with a lower risk of problem behaviour for children in middle childhood, in part explained by sociodemographic characteristics of families and the apparent psychological and socioeconomic benefits of employment. Results for mothers' transitions in or out of the labour market suggest that child problem behaviour is influenced by current status, over and above diverse earlier experiences of employment and non-employment. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  1. Family employment and child socioemotional behaviour: longitudinal findings from the UK Millennium Cohort Study

    PubMed Central

    Hope, Steven; Pearce, Anna; Whitehead, Margaret; Law, Catherine

    2014-01-01

    Background Levels of paid employment in two parent and lone parent families have increased in the UK but evidence of its impact on child socioemotional behaviour is limited and inconsistent. Methods We conducted a longitudinal analysis using the first four sweeps of the Millennium Cohort Study (9 months, 3 years, 5 years and 7 years) to investigate the influence of family employment trajectories in the early years on socioemotional behaviour at 7 years, unadjusted and adjusted for covariates. In addition, mothers’ employment was investigated separately. Results Children from families where no parent was employed for one or more sweeps were at a greater risk of socioemotional problem behaviour compared with those where a parent was continuously employed, even after adjustment for covariates. Children of mothers who were non-employed for one or more sweeps were at greater risk of problem behaviour compared with mothers who were employed at all sweeps. Adjustment for covariates fully attenuated the excess risk for children whose mothers had moved into employment by the time they were 7 years. In contrast, the elevated risk associated with continuous non-employment and a single transition out of employment was attenuated after adjustment for early covariates, fathers’ employment, household income and mothers’ psychological distress at 7 years, but remained significant. Conclusions Family and mothers’ employment were associated with a lower risk of problem behaviour for children in middle childhood, in part explained by sociodemographic characteristics of families and the apparent psychological and socioeconomic benefits of employment. Results for mothers’ transitions in or out of the labour market suggest that child problem behaviour is influenced by current status, over and above diverse earlier experiences of employment and non-employment. PMID:24889054

  2. Biotransformation of isofraxetin-6-O-β-d-glucopyranoside by Angelica sinensis (Oliv.) Diels callus.

    PubMed

    Zhou, Di; Zhang, Yuhua; Jiang, Zhe; Hou, Yue; Jiao, Kun; Yan, Chunyan; Li, Ning

    2017-01-15

    Isofraxetin-6-O-β-d-glucopyranoside, identified from traditional medicinal herbal Xanthoceras sorbifolia Bunge, has been demonstrated to be a natural neuroinflammatory inhibitor. In order to obtain more derivatives with potential anti-neuroinflammatory effects, biotransformation was carried out. According to the characteristics of coumarin skeleton, suspension cultures of Angelica sinensis (Oliv.) Diels callus (A. sinensis callus) were employed because of the presence of diverse phenylpropanoids biosynthetic enzymes. As a result, 15 products were yielded from the suspension cultures, including a new coumarin: 8'-dehydroxymethyl cleomiscosin A (1), together with 14 known compounds. Their structures were elucidated by extensive spectroscopic analysis. Furthermore, the biotransformed pathways were discussed. Among them, compound 13 was transformed from isofraxetin-6-O-β-d-glucopyranoside, while compounds 1-6, 10-12, 14-15 were derived from the culture medium stimulated by the substrate. The biotransformation processes include hydroxylation, oxidation and esterification. Furthermore, their inhibitory effects on lipopolysaccharide (LPS)-activated nitric oxide (NO) production were evaluated in BV2 microglial cells. It is worth noting that, 1, 1'-methanediylbis(4-methoxybenzene) (3), obtucarbamates A (5), 2-nonyl-4-hydroxyquinoline N-oxide (10) and 1H-indole-3-carbaldehyde (11) exhibited significant inhibitory effect against neuroinflammation with IC50 values at 1.22, 10.57, 1.02 and 0.76μM respectively, much stronger than that of the positive control minocycline (IC50 35.82μM). Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Biotransformation of rice bran to ferulic acid by pediococcal isolates.

    PubMed

    Kaur, Baljinder; Chakraborty, Debkumar; Kaur, Gundeep; Kaur, Gaganjot

    2013-06-01

    Ferulic acid (FA) is widely used in foods, in beverages, and in various pharmaceutical industries as a precursor of vanillin. FA biotransformation can occur during the growth of lactic acid bacteria (LAB), and its conversion to other phenolic derivatives is observed by many scientists, where ferulic acid esterase (FAE) and ferulic acid decarboxylase (FDC) play significant roles. The present study aimed at screening a panel of LAB for their ability to release FA from rice bran, an agro waste material. FAE and FDC activities were analyzed for the preliminary screening of various dairy isolates. Two Pediococcus acidilactici isolates were selected for studying further the hydrolysis of FA from rice bran and its bioconversion into phenolic derivatives like 4-ethylphenol, vanillin, vanillic acid, and vanillyl alcohol. P. acidilactici M16, a probiotic isolate, has great potential for the production of FA from rice bran and could be exploited as starter culture in the food industry for the production of biovanillin.

  4. Biotransformation of trinitrotoluene (TNT) by Streptomyces species

    SciTech Connect

    Funk, S.B.; Pasti-Grigsby, M.B.; Felicione, E.C.; Crawford, D.L.

    1995-12-31

    Composting has been proposed as one process for use in the bioremediation of 2,4,6 trinitrotoluene (TNT)-contaminated soils. However, the biotransformations of TNT that occur during composting, and the specific compost microorganisms involved in TNT metabolism, are not well understood. Both mesophilic and thermophilic actinomycetes are important participants in the biodegradation of organic matter, and possibly TNT, in composts. Here the authors report on the biotransformation of TNT by Streptomyces species growing aerobically in a liquid medium supplemented with 10 to 100 mg/L of TNT. Streptomyces spp. are able to completely remove TNT from the culture medium within 24 hours. As has been observed with other bacteria, these streptomycetes transform TNT first by reducing the 4-nitro and 2-nitro groups to the corresponding amino group; reducing TNT first to 4-amino-2,6-dinitrotoluene and then 2,4-diamino-6-nitrotoluene. These intermediates are transitory and are themselves removed from the medium within 7 days.

  5. The Transformer database: biotransformation of xenobiotics

    PubMed Central

    Hoffmann, Michael F.; Preissner, Sarah C.; Nickel, Janette; Dunkel, Mathias; Preissner, Robert; Preissner, Saskia

    2014-01-01

    As the number of prescribed drugs is constantly rising, drug–drug interactions are an important issue. The simultaneous administration of several drugs can cause severe adverse effects based on interactions with the same metabolizing enzyme(s). The Transformer database (http://bioinformatics.charite.de/transformer) contains integrated information on the three phases of biotransformation (modification, conjugation and excretion) of 3000 drugs and >350 relevant food ingredients (e.g. grapefruit juice) and herbs, which are catalyzed by 400 proteins. A total of 100 000 interactions were found through text mining and manual validation. The 3D structures of 200 relevant proteins are included. The database enables users to search for drugs with a visual display of known interactions with phase I (Cytochrome P450) and phase II enzymes, transporters, food and herbs. For each interaction, PubMed references are given. To detect mutual impairments of drugs, the drug-cocktail tool displays interactions between selected drugs. By choosing the indication for a drug, the tool offers suggestions for alternative medications to avoid metabolic conflicts. Drug interactions can also be visualized in an interactive network view. Additionally, prodrugs, including their mechanisms of activation, and further information on enzymes of biotransformation, including 3D models, can be viewed. PMID:24334957

  6. The Transformer database: biotransformation of xenobiotics.

    PubMed

    Hoffmann, Michael F; Preissner, Sarah C; Nickel, Janette; Dunkel, Mathias; Preissner, Robert; Preissner, Saskia

    2014-01-01

    As the number of prescribed drugs is constantly rising, drug-drug interactions are an important issue. The simultaneous administration of several drugs can cause severe adverse effects based on interactions with the same metabolizing enzyme(s). The Transformer database (http://bioinformatics.charite.de/transformer) contains integrated information on the three phases of biotransformation (modification, conjugation and excretion) of 3000 drugs and >350 relevant food ingredients (e.g. grapefruit juice) and herbs, which are catalyzed by 400 proteins. A total of 100,000 interactions were found through text mining and manual validation. The 3D structures of 200 relevant proteins are included. The database enables users to search for drugs with a visual display of known interactions with phase I (Cytochrome P450) and phase II enzymes, transporters, food and herbs. For each interaction, PubMed references are given. To detect mutual impairments of drugs, the drug-cocktail tool displays interactions between selected drugs. By choosing the indication for a drug, the tool offers suggestions for alternative medications to avoid metabolic conflicts. Drug interactions can also be visualized in an interactive network view. Additionally, prodrugs, including their mechanisms of activation, and further information on enzymes of biotransformation, including 3D models, can be viewed.

  7. Microbial Biotransformation to Obtain New Antifungals

    PubMed Central

    Bianchini, Luiz F.; Arruda, Maria F. C.; Vieira, Sergio R.; Campelo, Patrícia M. S.; Grégio, Ana M. T.; Rosa, Edvaldo A. R.

    2015-01-01

    Antifungal drugs belong to few chemical groups and such low diversity limits the therapeutic choices. The urgent need of innovative options has pushed researchers to search new bioactive molecules. Literature regarding the last 15 years reveals that different research groups have used different approaches to achieve such goal. However, the discovery of molecules with different mechanisms of action still demands considerable time and efforts. This review was conceived to present how Pharmaceutical Biotechnology might contribute to the discovery of molecules with antifungal properties by microbial biotransformation procedures. Authors present some aspects of (1) microbial biotransformation of herbal medicines and food; (2) possibility of major and minor molecular amendments in existing molecules by biocatalysis; (3) methodological improvements in processes involving whole cells and immobilized enzymes; (4) potential of endophytic fungi to produce antimicrobials by bioconversions; and (5) in silico research driving to the improvement of molecules. All these issues belong to a new conception of transformation procedures, so-called “green chemistry,” which aims the highest possible efficiency with reduced production of waste and the smallest environmental impact. PMID:26733974

  8. Mars Aeronomy Explorer (MAX): Study Employing Distributed Micro-Spacecraft

    NASA Technical Reports Server (NTRS)

    Shotwell, Robert F.; Gray, Andrew A.; Illsley, Peter M.; Johnson, M.; Sherwood, Robert L.; Vozoff, M.; Ziemer, John K.

    2005-01-01

    An overview of a Mars Aeronomy Explorer (MAX) mission design study performed at NASA's Jet Propulsion Laboratory is presented herein. The mission design consists of ten micro-spacecraft orbiters launched on a Delta IV to Mars polar orbit to determine the spatial, diurnal and seasonal variation of the constituents of the Martian upper atmosphere and ionosphere over the course of one Martian year. The spacecraft are designed to allow penetration of the upper atmosphere to at least 90 km. This property coupled with orbit precession will yield knowledge of the nature of the solar wind interaction with Mars, the influence of the Mars crustal magnetic field on ionospheric processes, and the measurement of present thermal and nonthermal escape rates of atmospheric constituents. The mission design incorporates alternative design paradigms that are more appropriate for-and in some cases motivate-distributed micro-spacecraft. These design paradigms are not defined by a simple set of rules, but rather a way of thinking about the function of instruments, mission reliability/risk, and cost in a systemic framework.

  9. Mars Aeronomy Explorer (MAX): Study Employing Distributed Micro-Spacecraft

    NASA Technical Reports Server (NTRS)

    Shotwell, Robert F.; Gray, Andrew A.; Illsley, Peter M.; Johnson, M.; Sherwood, Robert L.; Vozoff, M.; Ziemer, John K.

    2005-01-01

    An overview of a Mars Aeronomy Explorer (MAX) mission design study performed at NASA's Jet Propulsion Laboratory is presented herein. The mission design consists of ten micro-spacecraft orbiters launched on a Delta IV to Mars polar orbit to determine the spatial, diurnal and seasonal variation of the constituents of the Martian upper atmosphere and ionosphere over the course of one Martian year. The spacecraft are designed to allow penetration of the upper atmosphere to at least 90 km. This property coupled with orbit precession will yield knowledge of the nature of the solar wind interaction with Mars, the influence of the Mars crustal magnetic field on ionospheric processes, and the measurement of present thermal and nonthermal escape rates of atmospheric constituents. The mission design incorporates alternative design paradigms that are more appropriate for-and in some cases motivate-distributed micro-spacecraft. These design paradigms are not defined by a simple set of rules, but rather a way of thinking about the function of instruments, mission reliability/risk, and cost in a systemic framework.

  10. Differences in sickness absence between self-employed and employed doctors: a cross-sectional study on national sample of Norwegian doctors in 2010.

    PubMed

    Rosta, Judith; Tellnes, Gunnar; Aasland, Olaf G

    2014-05-02

    Doctors have a low prevalence of sickness absence. Employment status is a determinant in the multifactorial background of sickness absence. The effect of doctors' employment status on sickness absence is unexplored. The study compares the number of sickness absence days during the last 12 months and the impact of employment status, psychosocial work stress, self-rated health and demographics on sickness absence between self-employed practitioners and employed hospital doctors in Norway. The study population consisted of a representative sample of 521 employed interns and consultants and 313 self-employed GPs and private practice specialists in Norway, who received postal questionnaires in 2010. The questionnaires contained items on sickness absence days during the last 12 months, employment status, demographics, self-rated health, professional autonomy and psychosocial work stress. 84% (95% CI 80 to 88%) of self-employed and 60% (95% CI 55 to 64%) of employed doctors reported no absence at all last year. In three multivariate logistic regression models with sickness absence as response variable, employment category was a highly significant predictor for absence vs. no absence, 1 to 3 days of absence vs. no absence and 4 to 99 days of absence vs. no absence), while in a model with 100 or more days of absence vs. no absence, there was no difference between employment categories, suggesting that serious chronic disease or injury is less dependent on employment category. Average or poor self-rated health and low professional autonomy, were also significant predictors of sickness absence, while psychosocial work stress, age and gender were not. Self-employed GPs and private practice specialist reported lower sickness absence than employed hospital doctors. Differences in sickness compensation, and organisational and individual factors may to a certain extent explain this finding.

  11. Aerobic biotransformation of polyfluoroalkyl phosphate esters (PAPs) in soil.

    PubMed

    Liu, Chen; Liu, Jinxia

    2016-05-01

    Microbial transformation of polyfluoroalkyl phosphate esters (PAPs) into perfluorocarboxylic acids (PFCAs) has recently been confirmed to occur in activated sludge and soil. However, there lacks quantitative information about the half-lives of the PAPs and their significance as the precursors to PFCAs. In the present study, the biotransformation of 6:2 and 8:2 diPAP in aerobic soil was investigated in semi-dynamics reactors using improved sample preparation methods. To develop an efficient extraction method for PAPs, six different extraction solvents were compared, and the phenomenon of solvent-enhanced hydrolysis was investigated. It was found that adding acetic acid could enhance the recoveries of the diPAPs and inhibit undesirable hydrolysis during solvent extraction of soil. However 6:2 and 8:2 monoPAPs, which are the first breakdown products from diPAPs, were found to be unstable in the six solvents tested and quickly hydrolyzed to form fluorotelomer alcohols. Therefore reliable measurement of the monoPAPs from a live soil was not achievable. The apparent DT50 values of 6:2 diPAP and 8:2 diPAP biotransformation were estimated to be 12 and > 1000 days, respectively, using a double first-order in parallel model. At the end of incubation of day 112, the major degradation products of 6:2 diPAP were 5:3 fluorotelomer carboxylic acid (5:3 acid, 9.3% by mole), perfluoropentanoic acid (PFPeA, 6.4%) and perfluorohexanoic acid (PFHxA, 6.0%). The primary product of 8:2 diPAP was perfluorooctanoic acid (PFOA, 2.1%). The approximately linear relationship between the half-lives of eleven polyfluoroalkyl and perfluoroalkyl substances (PFASs, including 6:2 and 8:2 diPAPs) that biotransform in aerobic soils and their molecular weights suggested that the molecular weight is a good indicator of the general stability of low-molecular-weight PFAS-based compounds in aerobic soils. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Maternal employment and breast-feeding initiation: findings from the Millennium Cohort Study.

    PubMed

    Hawkins, Summer S; Griffiths, Lucy J; Dezateux, Carol; Law, Catherine

    2007-05-01

    Maternal employment rates have increased rapidly in recent years and little is known about how this influences whether women start breast feeding. We examined data from the Millennium Cohort Study to determine whether a mother's employment status (full-time, part-time, self-employed, on leave, not employed/student) and employment characteristics are related to breast-feeding initiation. This analysis comprised 14 830 white mothers from Britain and Ireland (6917 employed) with singleton babies, born from 2000 to 2002. Information was obtained on infant feeding history and mother's employment when the cohort child was 9 months old. We found that women employed full-time were less likely to initiate breast feeding than mothers who were not employed/students, after adjustment for confounding factors [adjusted rate ratio (aRR) = 0.92; 95% confidence interval (CI) 0.89, 0.96]; however, there were no differences in breast-feeding initiation between mothers employed part-time, self-employed, or on leave and mothers who were not employed/students. Among employed mothers, those who returned to work within 4 months postpartum were less likely to start breast feeding than women who returned at 5 or 6 months [aRR = 0.95; 95% CI 0.92, 0.99], and women who returned within the first 6 weeks were much less likely to start breast feeding [aRR = 0.85; 95% CI 0.77, 0.94]. Mothers returning for financial reasons were also less likely to initiate breast feeding [aRR = 0.96; 95% CI 0.93, 0.99] than those who returned for other reasons. Policies to increase breast feeding should address how both the time and circumstances of a mother's return to employment postpartum influence whether she decides to start breast feeding.

  13. Antifungal activity and biotransformation of diisophorone by Botrytis cinerea.

    PubMed

    Daoubi, Mourad; Deligeorgopoulou, Athina; Macías-Sánchez, Antonio J; Hernández-Galán, Rosario; Hitchcock, Peter B; Hanson, James R; Collado, Isidro G

    2005-07-27

    Diisophorone (1) was tested against two strains of the necrotrophic plant pathogen Botrytis cinerea. Fungal sensitivity varied according to the strain. B. cinera 2100 was more sensitive than B. cinereaUCA992: its mycelial growth was significantly inhibited at concentrations of 50 ppm and above. Although diisophorone (1) showed an effective control of B. cinerea, a detoxification mechanism was present. The detoxification of racemic diisophorone (1) by B. cinerea was investigated. Incubation with two strains of B. cinerea gave one and four biotransformation products (2-5), respectively. Their structures were established as the known 8beta-hydroxydiisophorone (2), 6alpha-hydroxydiisophorone (3), 6beta-hydroxydiisophorone (4) and 8beta,14beta-dihydroxydiisophorone (5) on the basis of their spectroscopic data, including two-dimensional NMR analysis [heteronuclear multiple quantum coherence (HMQC), heteronuclear multiple bond correlation (HMBC), and nuclear Overhauser enhancement spectroscopy (NOESY)] and an X-ray crystallographic study.

  14. Biotransformation of (-)beta-pinene by Aspergillus niger ATCC 9642.

    PubMed

    Toniazzo, Geciane; de Oliveira, Débora; Dariva, Cláudio; Oestreicher, Enrique Guillermo; Antunes, Octávio A C

    2005-01-01

    The main objective of this work was to investigate the biotransformations of (-)alpha-pinene, (-)beta-pinene, and (+) limonene by Aspergillus niger ATCC 9642. The culture conditions involved--concentration of cosolvent (EtOH), substrate applied, and sequential addition of substrates were--investigated. Adaptation of the precultures with small amounts of substrate was also studied. The experiments were performed in conical flasks with liquid cultures. This strain of A. niger was able to convert only (-)beta-pinene into alpha-terpineol. An optimum conversion of (-)beta-pinene into alpha-terpineol of about 4% was obtained when the substrate was applied as a diluted solution in EtOH and sequential addition of substrate was used.

  15. Jane Addams Resource Corporation: A Case Study of a Sectoral Employment Development Approach. Sectoral Employment Development Learning Project Case Studies Series.

    ERIC Educational Resources Information Center

    Glasmeier, Amy K.; Nelson, Candace; Thompson, Jeffery W.

    This case study on the Jane Addams Resource Corporation (JARC) is the third of six sectoral studies to provide an in-depth look at individual sectoral employment development programs and their interaction within distinct economic and industry environments. It explores a community-based organization that developed specialized metalworking and…

  16. Competitive employment for consumers who are legally blind: a 10-year retrospective study.

    PubMed

    Bell, Edward

    2010-01-01

    Vocational rehabilitation consumers who are legally blind are a subgroup of the larger population of individuals with disabilities who have suffered high rates of unemployment; yet, the evaluation standards and performance indicators of the Rehabilitation Services Administration (RSA) show that each year, the rates of employment for individuals with disabilities continue to increase overall. The question being investigated is, Has the employment rate similarly increased for this subgroup of consumers? Using the RSA-911 data system, this study investigated the competitive employment rates for consumers who are legally blind over a 10-year period spanning fiscal years 1997 to 2007. This study also compares differences in wages for consumers who were employed when they applied for services versus when they retained or advanced in employment at case closures. Results show that rates of employment and wages have steadily increased for consumers who are legally blind over the period of analysis.

  17. Recommended Skill Requirements of Recent Management Information Systems Graduates for Employment: A Modified Delphi Study

    ERIC Educational Resources Information Center

    Strnad, Michael A., Sr.

    2013-01-01

    The purpose of this Modified Delphi study was to achieve a consensus and forecast a prediction from expert IT hiring managers on what skills are required of MIS graduates for employment. In doing so, guidance could be provided to academic leaders who design curricula for MIS students on the required skills for employment. This study was conducted…

  18. Recommended Skill Requirements of Recent Management Information Systems Graduates for Employment: A Modified Delphi Study

    ERIC Educational Resources Information Center

    Strnad, Michael A., Sr.

    2013-01-01

    The purpose of this Modified Delphi study was to achieve a consensus and forecast a prediction from expert IT hiring managers on what skills are required of MIS graduates for employment. In doing so, guidance could be provided to academic leaders who design curricula for MIS students on the required skills for employment. This study was conducted…

  19. Best Practices in Supported Employment: A Study of the Tennessee Initiative.

    ERIC Educational Resources Information Center

    Petty, Debra Martin; And Others

    The report presents six papers describing a Tennessee study to assess the status of the supported employment initiative, determine the importance and implementation of best practice elements, and ascertain perceptions of supported employment customers toward implementation. Major findings include the following: at the time of the study supported…

  20. A Case Study Understanding Employability through the Lens of Human Resource Executives

    ERIC Educational Resources Information Center

    Stokes, Carmeda L.

    2013-01-01

    The purpose of this qualitative multiple case study was to examine HR executives' perspectives on employability enhancement for employees and how it is operationalized in their workplace. The exploratory questions that guided the study were, What are the perspectives of HR executives regarding employability enhancement for employees, and In what…

  1. A Case Study Understanding Employability through the Lens of Human Resource Executives

    ERIC Educational Resources Information Center

    Stokes, Carmeda L.

    2013-01-01

    The purpose of this qualitative multiple case study was to examine HR executives' perspectives on employability enhancement for employees and how it is operationalized in their workplace. The exploratory questions that guided the study were, What are the perspectives of HR executives regarding employability enhancement for employees, and In what…

  2. Best Practices in Supported Employment: A Study of the Tennessee Initiative.

    ERIC Educational Resources Information Center

    Petty, Debra Martin; And Others

    The report presents six papers describing a Tennessee study to assess the status of the supported employment initiative, determine the importance and implementation of best practice elements, and ascertain perceptions of supported employment customers toward implementation. Major findings include the following: at the time of the study supported…

  3. Enzymatic biotransformation of synthetic dyes.

    PubMed

    Rodríguez-Couto, S

    2009-11-01

    Environmental pollution by discharge of dye-containing effluents represents a serious ecological concern in many countries. Public demands for colour-free discharges to receiving waters have made decolouration of a variety of industrial wastewater a top priority. The current existing techniques for dye removal have several drawbacks such as high cost, low efficiency, use of large amounts of chemicals and formation of toxic sub-products. This has impelled the search for alternative methods such as those based on oxidative enzymes. This approach is believed to be a promising technology since it is cost-effective, environmentally friendly and does not produce sludge. Enzymatic transformation of synthetic dyes can be described as the conversion of dye molecules by enzymes into simpler and generally colourless molecules. Detailed characterisation of the metabolites produced during enzymatic transformation of synthetic dyes as well as ecotoxicity studies is of great importance to assess the effectiveness of the biodegradation process. However, most reports on the biotreatment of dyes mainly deal with decolouration and there are few reports on the reduction in toxicity or on the identification of the biodegradation products. This implies a limitation to assess their true technical potential.

  4. Biotransformation of norgestimate in women

    SciTech Connect

    Alton, K.B.; Hetyei, N.S.; Shaw, C.; Patrick, J.E.

    1984-01-01

    The metabolism of norgestimate (ORF-10131; /sup 14/C-d-13-ethyl-17-acetoxy-18,19-dinor-17 alpha-pregn-4-en-20- yn -3-oxime) was studied in humans. Compound labeled with carbon-14 in the 17 alpha-ethynyl group was administered to four female subjects. An average of 46.8 percent of the administered radioactivity was excreted in the urine and 36.8 percent in the feces over a two-week collection period. About 12 percent of the urinary radioactivity represented freely extractable metabolites and another 57 percent consisted of extractable material released by enzyme hydrolysis. The ethynylated metabolites of norgestimate were separated from endogenous compounds and non- ethynylated metabolites by silver- sulfoethyl cellulose column chromatography. Metabolites were subsequently isolated by high performance liquid chromatography and thin layer chromatography. The identification of five urinary metabolites was accomplished by combined gas-liquid chromatography/mass spectrometry. These metabolites include norgestrel, 16 beta- hydroxynorgestrel, 2 alpha- hydroxynorgestrel, 3 alpha, 5 beta- tetrahydronorgestrel, and a fifth trihydroxylated metabolite of undetermined stereochemical configuration; 3,16-dihydroxy-5- tetrahydronorgestrel .

  5. Species-specific isotope tracers to study the accumulation and biotransformation of mixtures of inorganic and methyl mercury by the microalga Chlamydomonas reinhardtii.

    PubMed

    Bravo, Andrea Garcia; Le Faucheur, Séverine; Monperrus, Mathilde; Amouroux, David; Slaveykova, Vera I

    2014-09-01

    The present study demonstrates that species-specific isotope tracing is an useful tool to precisely measure Hg accumulation and transformations capabilities of living organisms at concentrations naturally encountered in the environment. To that end, a phytoplanktonic green alga Chlamydomonas reinhardtii Dangeard (Chlamydomonadales, Chlorophyceae) was exposed to mixtures of (199)-isotopically enriched inorganic mercury ((199)IHg) and of (201)-isotopically enriched monomethylmercury ((201)CH3Hg) at a concentration range between less than 1 pM to 4 nM. Additionally, one exposure concentration of both mercury species was also studied separately to evaluate possible interactive effects. No difference in the intracellular contents was observed for algae exposed to (199)IHg and (201)CH3Hg alone or in their mixture, suggesting similar accumulation capacity for both species at the studied concentrations. Demethylation of (201)CH3Hg was observed at the highest exposure concentrations, whereas no methylation was detected.

  6. Behavior of the potential antitumor V(IV)O complexes formed by flavonoid ligands. 2. Characterization of sulfonate derivatives of quercetin and morin, interaction with the bioligands of the plasma and preliminary biotransformation studies.

    PubMed

    Sanna, Daniele; Ugone, Valeria; Pisano, Luisa; Serra, Maria; Micera, Giovanni; Garribba, Eugenio

    2015-12-01

    The biotransformation in the plasma and red blood cells of two potential antitumor V(IV)O complexes formed by flavonoid ligands (quercetin or que and morin or mor) and their sulfonic derivatives (quercetin-5'-sulfonic acid or que(S) and morin-5'-sulfonic acid or mor(S)) was studied by spectroscopic (EPR, Electron Paramagnetic Resonance) and computational (DFT, Density Functional Theory) methods. Que and que(S) form with V(IV)O stable complexes, and in the systems with apo-transferrin (apo-hTf) and albumin (HSA) VO(que)2 and VO(que(S))2 remain unchanged. VO(mor)2 and VO(mor(S))2 undergo displacement reactions to give the partial formation of (VO)x(HSA) and (VO)(apo-hTf)/(VO)2(apo-hTf); moreover, mor(S) forms with apo-transferrin and albumin mixed species VO-mor(S)-apo-hTf and VO-mor(S)-HSA. In the systems with apo-hTf and HSA anisotropic EPR spectra at room temperature are detected in which the protein is not directly coordinated to V(IV)O(2+) ion. This is explained assuming that the bis-chelated complexes interact strongly with the proteins through a network of hydrogen bonds with the polar groups present on the protein surface. It is suggested that this "indirect" transport of V(IV)O species could be common to all the species containing ligands which can interact with the blood proteins. Uptake experiments by red blood cells were also carried out, using vanadium concentration of 5.0×10(-4)M and incubation time in the range 0-160min. VO(que)2/VO(que(S))2 and VO(mor)2/VO(mor(S))2 cross the erythrocytes membrane and in the cytosol VO(que)2/VO(que(S))2 do not transform, whereas VO(mor)2/VO(mor(S))2 give the partial formation of mixed species with hemoglobin (Hb) and other V(IV)O complexes. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Biotransformation of Hg(II) by Cyanobacteria▿ †

    PubMed Central

    Lefebvre, Daniel D.; Kelly, David; Budd, Kenneth

    2007-01-01

    The biotransformation of Hg(II) by cyanobacteria was investigated under aerobic and pH-controlled culture conditions. Mercury was supplied as HgCl2 in amounts emulating those found under heavily impacted environmental conditions where bioremediation would be appropriate. The analytical procedures used to measure mercury within the culture solution, including that in the cyanobacterial cells, used reduction under both acid and alkaline conditions in the presence of SnCl2. Acid reduction detected free Hg(II) ions and its complexes, whereas alkaline reduction revealed that meta-cinnabar (β-HgS) constituted the major biotransformed and cellularly associated mercury pool. This was true for all investigated species of cyanobacteria: Limnothrix planctonica (Lemm.), Synechococcus leopoldiensis (Racib.) Komarek, and Phormidium limnetica (Lemm.). From the outset of mercury exposure, there was rapid synthesis of β-HgS and Hg(0); however, the production rate for the latter decreased quickly. Inhibitory studies using dimethylfumarate and iodoacetamide to modify intra- and extracellular thiols, respectively, revealed that the former thiol pool was required for the conversion of Hg(II) into β-HgS. In addition, increasing the temperature enhanced the amount of β-HgS produced, with a concomitant decrease in Hg(0) volatilization. These findings suggest that in the environment, cyanobacteria at the air-water interface could act to convert substantial amounts of Hg(II) into β-HgS. Furthermore, the efficiency of conversion into β-HgS by cyanobacteria may lead to the development of applications in the bioremediation of mercury. PMID:17071784

  8. Biotransformation of lepidocrocite in the presence of quinones and flavins

    NASA Astrophysics Data System (ADS)

    Bae, Sungjun; Lee, Woojin

    2013-08-01

    This study investigated the bioreduction of lepidocrocite (γ-FeIIIOOH) and its mineral transformation in the presence of exogenous (quinones) and endogenous (flavins) electron transfer mediators (ETMs) at low concentrations of the ETMs and bacterial cells (Shewanella putrefaciens CN32). It is very important to investigate the bioreduction of lepidocrocite in the presence of different ETMs because biotransformation of Fe(III)-containing minerals can be stimulated by ETMs and affect fate and transport of contaminants in contaminated environments. In the absence of phosphate, green rust formation was observed with fast Fe(II) production rate (0.44-0.56 mM d-1) during the bioreduction of lepidocrocite with exogenous ETMs, while goethite formed at slow Fe(II) production rate (0.24-0.29 mM d-1) with endogenous ETMs. In the presence of phosphate, formation of green rust and vivianite was observed with fast Fe(II) production rate (0.54-0.74 mM d-1) during the bioreduction of lepidocrocite with exogenous ETMs, while vivianite formed at moderate Fe(II) production rate (0.36-0.40 mM d-1) with endogenous ETMs. Vivianite formed in all experimental cases with phosphate in a broad range of Fe(II) production rates (0.23-0.74 mM d-1). Our results (1) suggest that exogenous and endogenous ETMs can significantly but differently affect the biotransformation of lepidocrocite, especially at low concentrations of the ETMs and bacterial cells, (2) highlight the importance of Fe(II) production rate to determine the formation of specific biogenic minerals, (3) provide additional evidence that phosphate can significantly affect the bioreduction rate and the mineral transformation, and (4) help to understand the basic knowledge about complex interactions among microbial cell, soil mineral, and ETM in natural environments and engineered systems.

  9. Zinc Oxide Nanoparticles Supported Lipase Immobilization for Biotransformation in Organic Solvents: A Facile Synthesis of Geranyl Acetate, Effect of Operative Variables and Kinetic Study.

    PubMed

    Patel, Vrutika; Shah, Chandani; Deshpande, Milind; Madamwar, Datta

    2016-04-01

    The present study describes grafting of zinc oxide (ZnO) nanoparticles with polyethyleneimine (PEI) followed by modification with glutraldehyde used as the bridge for binding the enzyme to support. The prepared nanocomposites were then characterized using Fourier transform infrared spectroscopy, thermogravimetric analysis, and transmission electron microscopy, utilized for synthesis of geranyl acetate in n-hexane. Among all the three prepared nanocomposites (ZnO + PEI, ZnO + PEI + SAA, ZnO + PEI + GLU), Candida rugosa lipase immobilized on ZnO-PEI-GLU was found to be best for higher ester synthesis. The operating conditions that maximized geranyl acetate resulted in the highest yield of 94 % in 6 h, molar ratio of 0.1:0.4 M (geraniol/vinyl acetate) in the presence of n-hexane as reaction medium. Various kinetic parameters such as V max, K i(G), K m(G), and K m(VA) were determined using nonlinear regression analysis for order bi-bi mechanism. The kinetic study showed that reaction followed order bi-bi mechanism with inhibition by geraniol. Activation energy (E a ) was found to be lower for immobilized lipase (12.31 kJ mol(-1)) than crude lipase (19.04 kJ mol(-1)) indicating better catalytic efficiency of immobilized lipase. Immobilized biocatalyst demonstrated 2.23-fold increased catalytic activity than crude lipase and recycled 20 times. The studies revealed in this work showed a promising perspective of using low-cost nanobiocatalysts to overcome the well-known drawbacks of the chemical-catalyzed route.

  10. Comparative biotransformation and disposition studies of nabumetone in humans and minipigs using high-performance liquid chromatography with ultraviolet, fluorescence and mass spectrometric detection.

    PubMed

    Nobilis, M; Kopecký, J; Kvetina, J; Svoboda, Z; Pour, M; Kunes, J; Holcapek, M; Kolárová, L

    2003-08-08

    The disposition of the non-steroidal anti-inflammatory drug (NSAID) nabumetone after a single oral dose administration of nabumetone tablets to humans and minipigs was investigated. Nabumetone is a prodrug, which is metabolized in the organism to the principal pharmacodynamically active metabolite -- 6-methoxy-2-naphthylacetic acid (6-MNA), and some other minor metabolites (carbonyl group reduction products, O-desmethylation products and their conjugates with glucuronic and sulphuric acids). Standards of the above-mentioned metabolites were prepared using simple synthetic procedures and their structures were confirmed by NMR and mass spectrometry. A simple HPLC method for the simultaneous determination of nabumetone, 6-MNA and the other metabolites was developed, validated and used for xenobiochemical and pharmacokinetic studies in humans and minipigs and for distribution studies in minipigs. Naproxen was chosen as the internal standard (I.S.), both UV (for higher concentrations) and fluorescence detection (for very low concentrations) were used. The identity of the nabumetone metabolites in biological samples was confirmed using HPLC-MS experiments. Pharmacokinetics of nabumetone, 6-MNA and 6-HNA (6-hydroxy-2-naphthylacetic acid) in human and minipig plasma was evaluated and compared. The concentration levels of nabumetone metabolites in urine, bile and synovial fluid were also evaluated.

  11. Introduction to the WHO Commission on Social Determinants of Health Employment Conditions Network (EMCONET) study, with a glossary on employment relations.

    PubMed

    Benach, Joan; Muntaner, Carles; Solar, Orielle; Santana, Vilma; Quinlan, Michael

    2010-01-01

    Although the conditions and power relations of employment are known to be crucial health determinants for workers and their families, the nature of these relations and their effects on health have yet to be fully researched. Several types of employment--precarious employment in developed countries; informal sectors, child labor, slavery, and bonded labor in developing countries--expose workers to risky working conditions. Hazardous work and occupation-related diseases kill approximately 1,500 workers, globally, every day. Growing scientific evidence suggests that particular employment conditions, such as job insecurity and precarious employment, create adverse health effects; yet the limited number of studies and the poor quality of their methods prevent our understanding, globally, the complexity of employer-employee power relations, working conditions, levels of social protections, and the reality of employment-related health inequalities. This article introduces a special section on employment-related health inequalities, derived from the EMCONET approach, which focuses on (1) describing major methods and sources of information; (2) presenting theoretical models at the micro and macro levels; (3) presenting a typology of labor markets and welfare states worldwide; (4) describing the main findings in employment policies, including four key points for implementing strategies; and (5) suggesting new research developments, a policy agenda, and recommendations. This introduction includes a glossary of terms in the emerging area of employment conditions and health inequalities.

  12. Biotransformation of the Antibiotic Danofloxacin by Xylaria longipes Leads to an Efficient Reduction of Its Antibacterial Activity.

    PubMed

    Rusch, Marina; Kauschat, Annika; Spielmeyer, Astrid; Römpp, Andreas; Hausmann, Heike; Zorn, Holger; Hamscher, Gerd

    2015-08-12

    Fluoroquinolones are considered as critically important antibiotics. However, they are used in appreciable quantities in veterinary medicine. Liquid manure and feces can contain substantial amounts of unmetabolized antibiotics and, thus, antibiotics can enter the environment if manure is used for soil fertilization. In this study, the microbial biotransformation of the synthetic veterinary fluoroquinolone danofloxacin by the ascomycete Xylaria longipes was investigated. Fungal submerged cultures led to a regioselective and almost quantitative formation of a single metabolite within 3 days. The metabolite was unequivocally identified as danofloxacin N-oxide by high-resolution mass spectrometry and one- and two-dimensional nuclear magnetic resonance spectroscopic techniques. An oxidation of the terminal nitrogen of the substituted piperazine moiety of the substance led to a remarkable reduction of 80% of the initial antibacterial activity. Thus, fungal enzymes involved in the biotransformation process might possess the potential to reduce the entrance of antibiotics via biotransformation of these compounds.

  13. Experiencing Term-Time Employment as a Non-Traditional Aged University Student: A Welsh Study

    ERIC Educational Resources Information Center

    Mercer, Jenny; Clay, James; Etheridge, Leanne

    2016-01-01

    Engaging in term-time employment appears to be becoming a common feature of contemporary UK student life. This study examined the ways in which a cohort of full-time non-traditional aged students negotiated paid employment whilst pursuing a full-time higher education course in Wales. Taking a qualitative approach to explore this further,…

  14. Experiencing Term-Time Employment as a Non-Traditional Aged University Student: A Welsh Study

    ERIC Educational Resources Information Center

    Mercer, Jenny; Clay, James; Etheridge, Leanne

    2016-01-01

    Engaging in term-time employment appears to be becoming a common feature of contemporary UK student life. This study examined the ways in which a cohort of full-time non-traditional aged students negotiated paid employment whilst pursuing a full-time higher education course in Wales. Taking a qualitative approach to explore this further,…

  15. Supported Employment for Young People with Intellectual Disabilities Facilitated through Peer Support: A Pilot Study

    ERIC Educational Resources Information Center

    Kaehne, Axel; Beyer, Stephen

    2013-01-01

    The article reports the evaluation of a small-scale-supported employment project in a local authority in England. The study examined whether or not the peer support model could be used to deliver supported employment to a group of young people with intellectual disabilities. We utilised a mixed-method approach involving activity data, family…

  16. Teenage Employment: A Study of Low Income Youth in Houston, Texas.

    ERIC Educational Resources Information Center

    Champagne, Joseph E.; Prater, Robert L.

    To analyze the reason for the high rate of Negro teenage unemployment, the employment experience of 256 Negro and white teenagers, aged 16 to 19 years, in Houston was examined about 1 year after they had graduated or dropped out of school. A questionnaire was developed and mailed to 250 major employers in the area. The study points out that one of…

  17. Supported Employment for Young People with Intellectual Disabilities Facilitated through Peer Support: A Pilot Study

    ERIC Educational Resources Information Center

    Kaehne, Axel; Beyer, Stephen

    2013-01-01

    The article reports the evaluation of a small-scale-supported employment project in a local authority in England. The study examined whether or not the peer support model could be used to deliver supported employment to a group of young people with intellectual disabilities. We utilised a mixed-method approach involving activity data, family…

  18. Getting Hired, Getting Trained; A Study of Industry Practices and Policies on Youth Employment.

    ERIC Educational Resources Information Center

    National Committee on Employment of Youth, Washington, DC.

    A study was made in 1964 in Hartford, Connecticut, and Winston-Salem and Charlotte, North Carolina, of prospects for employment and upgrading of young male entry workers. Few companies hired workers without a high school diploma; the majority required experience. Personal contact, public employment service, gate hires, and advertisements were the…

  19. Predictors of Employment for Youths with Visual Impairments: Findings from the Second National Longitudinal Transition Study

    ERIC Educational Resources Information Center

    McDonnall, Michele Capella

    2011-01-01

    The study reported here identified factors that predict employment for transition-age youths with visual impairments. Logistic regression was used to predict employment at two levels. Significant variables were early and recent work experiences, completion of a postsecondary program, difficulty with transportation, independent travel skills, and…

  20. Youth Employability. Monographs on Research and Policy Studies. Five Award-Winning Monographs.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. National Center for Research in Vocational Education.

    This document presents five winning entries in the second annual competition for papers reporting research and policy studies on the topic of youth employability. In their paper entitled "The Impact of Employment and Training Programs on the Work Attitudes of Disadvantaged Youth," Michael Forcier and Andrew Hahn review and synthesize the…

  1. Part-Time Employment Study. Class of 1973--Lewiston High School. Educational Experiences Outside the Classroom.

    ERIC Educational Resources Information Center

    Mahaney, Thomas F.

    This study sought to identify and categorized the responses of more than 1600 high school juniors, via personal interviews, to determine the impact of student employment on the student, school, and community. Those students who were employed were found to be a potent force on the local labor market in terms of jobs held, hours worked, money…

  2. Predictors of Employment for Youths with Visual Impairments: Findings from the Second National Longitudinal Transition Study

    ERIC Educational Resources Information Center

    McDonnall, Michele Capella

    2011-01-01

    The study reported here identified factors that predict employment for transition-age youths with visual impairments. Logistic regression was used to predict employment at two levels. Significant variables were early and recent work experiences, completion of a postsecondary program, difficulty with transportation, independent travel skills, and…

  3. Graduates Mean Business: A Study of Graduate Self-Employment and Business Start-Ups.

    ERIC Educational Resources Information Center

    Tackey, N. D.; Perryman, S.

    Self-employment among graduates of England's higher education institutions (HEIs) was examined. The study included five elements: literature review; qualitative development stage involving exploratory interviews with 16 key players and in-depth interviews with 15 self-employed graduates from Sussex University and the London Institute; mail survey…

  4. X-Ray Absorption And EPR Spectroscopic Studies of the Biotransformations of Chromium(Vi) in Mammalian Cells. Is Chromodulin An Artifact of Isolation Methods?

    SciTech Connect

    Levina, A.; Harris, H.H.; Lay, P.A.; /Sydney U.

    2007-07-10

    Very different biological activities are usually ascribed to Cr(VI) (a toxin and carcinogen) and Cr(III) (an antidiabetic agent), although recent evidence suggests that both these types of actions are likely to arise from cellular uptake of varying concentrations of Cr(VI). The first systematic study of XANES spectra of Cr(III) complexes formed in Cr(VI)-treated mammalian cells (A549, HepG2, V79, and C2C12 cell lines), and in subcellular fractions of A549 cells, has been performed using a library of XANES spectra of model Cr(III) complexes. The results of multiple linear regression analyses of XANES spectra, in combination with multiple-scattering fits of XAFS spectra, indicate that Cr(III) formed in Cr(VI)-treated cells is most likely to bind to carboxylato, amine, and imidazole residues of amino acids, and to a lesser extent to hydroxo or aqua ligands. A combination of XANES and EPR spectroscopic data for Cr(VI)-treated cells indicates that the main component of Cr(III) formed in such cells is bound to high-molecular-mass ligands (>30 kDa, probably proteins), but significant redistribution of Cr(III) occurs during the cell lysis, which leads to the formation of a low-molecular-mass (<30 kDa) Cr(III)-containing fraction. The spectroscopic (XANES, XAFS, and EPR) properties of this fraction were strikingly similar to those of the purported natural Cr(III)-containing factor, chromodulin, that was reported to be isolated from the reaction of Cr(VI) with liver. These data support the hypothesis that a chromodulin-like species, which is formed from such a reaction, is an artifact of the reported isolation procedure.

  5. Biotransformation and detoxication of molinate (Ordram) in fish

    SciTech Connect

    Tjeerdema, R.S.

    1987-01-01

    Bioconcentration, deputation, and biotransformation of molinate were compared in common carp (cyprinus carpio), striped bass (Morone saxatilis), and white sturgeon (acipenser transmontanus) using a flow-through metabolism system. When compared to static conditions, flowing water improved oxygenation, decreased chemical volatilization and remetabolism, and run through a macroreticular resin, improved waste-product collection. Metabolite analysis employed gradient high-pressure liquid chromatography. Exposure to 100 ..mu..g L/sup -1/ (ring-/sup 14/C)molinate for 24 h resulted in bioconcentration factors of 30.5 (carp), 25.3 (bass), and 19.7 (sturgeon); differences were not significant (all, P > 0.05). /sup 14/C depuration by common carp was significantly slower than that by either striped bass or white sturgeon (both, P < 0.01). All three species oxidized molinate to a number of products and hydrolyzed, or conjugated with glutathione (GSH), the sulfoxide or sulfone, ultimately producing the mercapturic acid; carp and sturgeon also formed a D-glucuronic acid conjugate. Common carp were significantly less capable of sulfoxidation and GSH conjugation than either striped bass (P < 0.05) or white sturgeon (P < 0.01). Therefore, the selective toxicity of molinate in carp may be due to less efficient depuration and metabolic deactivation.

  6. Biotransformation of caffeine, cotinine, and nicotine in stream sediments: Implications for use as wastewater indicators

    USGS Publications Warehouse

    Bradley, P.M.; Barber, L.B.; Kolpin, D.W.; McMahon, P.B.; Chapelle, F.H.

    2007-01-01

    Microbially catalyzed cleavage of the imadazole ring of caffeine was observed in stream sediments collected upstream and downstream of municipal wastewater treatment plants (WWTP) in three geographically separate stream systems. Microbial demethylation of the N-methyl component of cotinine and its metabolic precursor, nicotine, also was observed in these sediments. These findings indicate that stream sediment microorganisms are able to substantially alter the chemical structure and thus the analytical signatures of these candidate waste indicator compounds. The potential for in situ biotransformation must be considered if these compounds are employed as markers to identify the sources and track the fate of wastewater compounds in surface-water systems.

  7. Biotransformation of caffeine, cotinine, and nicotine in stream sediments: implications for use as wastewater indicators.

    PubMed

    Bradley, Paul M; Barber, Larry B; Kolpin, Dana W; McMahon, Peter B; Chapelle, Francis H

    2007-06-01

    Microbially catalyzed cleavage of the imadazole ring of caffeine was observed in stream sediments collected upstream and downstream of municipal wastewater treatment plants (WWTP) in three geographically separate stream systems. Microbial demethylation of the N-methyl component of cotinine and its metabolic precursor, nicotine, also was observed in these sediments. These findings indicate that stream sediment microorganisms are able to substantially alter the chemical structure and thus the analytical signatures of these candidate waste indicator compounds. The potential for in situ biotransformation must be considered if these compounds are employed as markers to identify the sources and track the fate of wastewater compounds in surface-water systems.

  8. Incremental improvements to the trout S9 biotransformation assay

    EPA Science Inventory

    In vitro substrate depletion methods have been used in conjunction with computational models to predict biotransformation impacts on chemical accumulation by fish. There is a consistent trend, however, toward overestimation of measured chemical residues resulting from controlled...

  9. Incremental improvements to the trout S9 biotransformation assay

    EPA Science Inventory

    In vitro substrate depletion methods have been used in conjunction with computational models to predict biotransformation impacts on chemical accumulation by fish. There is a consistent trend, however, toward overestimation of measured chemical residues resulting from controlled...

  10. THE NEGRO AND EMPLOYMENT OPPORTUNITIES IN THE SOUTH, THE SECOND OF A SERIES OF EMPLOYMENT STUDIES IN SOUTHERN CITIES.

    ERIC Educational Resources Information Center

    JONES, MAJOR J.; AND OTHERS

    STATISTICS REVEALED THAT 65 PERCENT OF A LOCAL NEGRO HIGH SCHOOL GRADUATING CLASS SOUGHT OPPORTUNITIES FOR EMPLOYMENT OUTSIDE OF CHATTANOOGA. IT IS INDICATED THAT, IN THE AREA, DISCRIMINATION WAS PRACTICED AGAINST THE NEGRO LONG BEFORE HE FILED HIS FIRST JOB APPLICATION. AN ANALYSIS OF EDUCATIONAL AND TRAINING OPPORTUNITIES REVEALED THAT EQUAL…

  11. Employment Policies of the United States and Japan. Report of the Joint United States-Japan Employment Study.

    ERIC Educational Resources Information Center

    Ministry of Labor, Tokyo (Japan).

    The U.S. Department of Labor and the Japanese Ministry of Labor cooperatively reviewed the employment policies in the two countries in an attempt to promote understanding and cooperation between them and to develop the human capacities of workers in both countries. The report is composed of four parts: (1) Introduction, (2) Policies and Programs…

  12. A longitudinal study of employment and skill acquisition among individuals with developmental disabilities.

    PubMed

    Stephens, Dawn L; Collins, Michael D; Dodder, Richard A

    2005-01-01

    Recent legislation, especially the Americans with Disabilities Act in 1990, generated the closure of institutions for people with disabilities and inclusion into community residences and employment. It has been well documented that individuals with developmental disabilities often experience difficulties with employment including both obtaining and maintaining jobs, and many researchers have looked for ways to make employment more successful [McConkey, R. & Mezza F. (2001). Employment aspirations of people with learning disabilities attending day centers. Journal of Learning Disabilities, 5(4), 309-318; Stevens, G. (2002). Employers' perceptions and practice in the employability of disabled people: a survey of companies in south east UK. Disability and Society, 17(7), 779-796; Capella, M., Roessler, R., & Hemmeria, K. (2002). Work-related skills awareness in high-school students with disabilities. Journal of Applied Rehabilitation Counseling, 33(2), 17-23; Ingraham, K., Rahimi, M., Tsang, H., Chan, F., & Oulvey, E. (2001). Work support groups in state vocational rehabilitation agency settings: a case study. Psychiatric Rehabilitation Skills, 5(1), 6-21; Gosling, V. & Cotterill, L. (2000). An employment project as a route to social inclusion for people with learning difficulties? Disability and Society, 15(7), 1001-1018; Neitupski, J. & Hamre-Nietupski, S. (2000). A systematic process for carving supported employment positions for people with severe disabilities. Journal of Developmental and Physical Disabilities, 12(2), 103-119]. While research has accumulated that has examined predictors of successful employment, this research assessed longitudinal outcomes of employment. Data were obtained from an existing data set of all known persons receiving services from the Developmental Disabilities Division of the Oklahoma Department of Human Services (N=2760). Results indicated that as people moved to employment, scores on adaptive skills increased, that as people moved

  13. Employment as a Social Determinant of Health: A Review of Longitudinal Studies Exploring the Relationship between Employment Status and Mental Health

    ERIC Educational Resources Information Center

    Hergenrather, Kenneth C.; Zeglin, Robert J.; McGuire-Kuletz, Maureen; Rhodes, Scott D.

    2015-01-01

    Purpose: To explore employment as a social determinant of health through examining the relationship between employment status and mental health. Method: The authors conducted a systematic review of 48 longitudinal studies conducted in Australia, Canada, Croatia, Germany, Ireland, Israel, the Netherlands, Norway, United Kingdom, and United States…

  14. Employment as a Social Determinant of Health: A Review of Longitudinal Studies Exploring the Relationship between Employment Status and Mental Health

    ERIC Educational Resources Information Center

    Hergenrather, Kenneth C.; Zeglin, Robert J.; McGuire-Kuletz, Maureen; Rhodes, Scott D.

    2015-01-01

    Purpose: To explore employment as a social determinant of health through examining the relationship between employment status and mental health. Method: The authors conducted a systematic review of 48 longitudinal studies conducted in Australia, Canada, Croatia, Germany, Ireland, Israel, the Netherlands, Norway, United Kingdom, and United States…

  15. Determinants of the sustained employment of physician assistants in hospitals: a qualitative study.

    PubMed

    Timmermans, Marijke J C; van Vught, Anneke J A H; Maassen, Irma T H M; Draaijer, Lisette; Hoofwijk, Anton G M; Spanier, Marcel; van Unen, Wijnand; Wensing, Michel; Laurant, Miranda G H

    2016-11-18

    To identify determinants of the initial employment of physician assistants (PAs) for inpatient care as well as of the sustainability of their employment. We conducted a qualitative study with semistructured interviews with care providers. Interviews continued until data saturation was achieved. All interviews were transcribed verbatim. A framework approach was used for data analysis. Codes were sorted by the themes, bringing similar concepts together. This study was conducted between June 2014 and May 2015 within 11 different hospital wards in the Netherlands. The wards varied in medical speciality, as well as in hospital type and the organisational model for inpatient care. Participant included staff physicians, residents, PAs and nurses. The following themes emerged to be important for the initial employment of PAs and the sustainability of their employment: the innovation, individual factors, professional interactions, incentives and resources, capacity for organisational change and social, political and legal factors. 10 years after the introduction of PAs, there was little discussion among the adopters about the added value of PAs, but organisational and financial uncertainties played an important role in the decision to employ and continue employment of PAs. Barriers to employ and continue PA employment were mostly a consequence of locally arranged restrictions by hospital management and staff physicians, as barriers regarding national laws, PA education and competencies seemed absent. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  16. Determinants of the sustained employment of physician assistants in hospitals: a qualitative study

    PubMed Central

    Timmermans, Marijke J C; van Vught, Anneke J A H; Maassen, Irma T H M; Draaijer, Lisette; Hoofwijk, Anton G M; Spanier, Marcel; van Unen, Wijnand; Wensing, Michel; Laurant, Miranda G H

    2016-01-01

    Objectives To identify determinants of the initial employment of physician assistants (PAs) for inpatient care as well as of the sustainability of their employment. Design We conducted a qualitative study with semistructured interviews with care providers. Interviews continued until data saturation was achieved. All interviews were transcribed verbatim. A framework approach was used for data analysis. Codes were sorted by the themes, bringing similar concepts together. Setting This study was conducted between June 2014 and May 2015 within 11 different hospital wards in the Netherlands. The wards varied in medical speciality, as well as in hospital type and the organisational model for inpatient care. Participants Participant included staff physicians, residents, PAs and nurses. Results The following themes emerged to be important for the initial employment of PAs and the sustainability of their employment: the innovation, individual factors, professional interactions, incentives and resources, capacity for organisational change and social, political and legal factors. Conclusions 10 years after the introduction of PAs, there was little discussion among the adopters about the added value of PAs, but organisational and financial uncertainties played an important role in the decision to employ and continue employment of PAs. Barriers to employ and continue PA employment were mostly a consequence of locally arranged restrictions by hospital management and staff physicians, as barriers regarding national laws, PA education and competencies seemed absent. PMID:27864243

  17. Short-term and long-term effects of childhood cancer on income from employment and employment status: A national cohort study in Sweden.

    PubMed

    Lindahl Norberg, Annika; Montgomery, Scott M; Bottai, Matteo; Heyman, Mats; Hovén, Emma I

    2017-04-01

    There is insufficient knowledge regarding the economic impact of childhood cancer on parents. The objectives of the current study were to investigate the short-term and long-term effects of childhood cancer on mothers' and fathers' income from employment and employment status. The study sample consisted of the parents of children diagnosed with cancer from 2004 to 2009 in Sweden (3626 parents of 1899 children). Annual register data concerning income from employment and employment status (employed/not employed) were retrieved from the Longitudinal Integration Database for Health Insurance and Labor Market Studies. Using generalized linear models, the mean income from employment and employment status were compared with a matched control cohort of 34,874 parents sampled from the general population. Parents' income was found to decrease significantly after the child's cancer diagnosis. The effect was most pronounced for mothers, whose income was reduced for 6 years after diagnosis, whereas fathers' income was similar to that of control fathers 3 years after the diagnosis. Mothers were more likely to stop working after a child's cancer diagnosis compared with controls. No association was found for fathers' employment status. Younger age of parents; lower level of education; and, among mothers, being born outside of Sweden were found to be associated with more adverse effects on income. Parents' income from employment and employment status appear to be adversely affected by having a child with cancer. Socioeconomic consequences are not distributed equally: the income of fathers appears to catch up after a few years, whereas mothers tend to be disadvantaged in their professional life for several years after a child's cancer diagnosis. Cancer 2017;123:1238-1248. © 2016 American Cancer Society. © 2016 American Cancer Society.

  18. Employer-Sponsored Health Insurance Coverage Limitations: Results from the Childhood Cancer Survivor Study

    PubMed Central

    Kirchhoff, Anne C.; Kuhlthau, Karen; Pajolek, Hannah; Leisenring, Wendy; Armstrong, Greg T.; Robison, Leslie L.; Park, Elyse R.

    2013-01-01

    Purpose The Affordable Care Act (ACA) will expand health insurance options for cancer survivors in the United States. It is unclear how this legislation will affect their access to employer-sponsored health insurance (ESI). We describe the health insurance experiences for survivors of childhood cancer with and without ESI. Methods We conducted a series of qualitative interviews with 32 adult survivors from the Childhood Cancer Survivor Study to assess their employment-related concerns and decisions regarding health insurance coverage. Interviews were performed from August to December 2009 and were recorded, transcribed, and content analyzed using NVivo 8. Results Uninsured survivors described ongoing employment limitations, such as being employed at part-time capacity, which affected their access to ESI coverage. These survivors acknowledged they could not afford insurance without employer support. Survivors on ESI had previously been denied health insurance due to their pre-existing health conditions until they obtained coverage through an employer. Survivors feared losing their ESI coverage, which created a disincentive to making career transitions. Others reported worries about insurance rescission if their cancer history was discovered. Survivors on ESI reported financial barriers in their ability to pay for health care. Conclusions Childhood cancer survivors face barriers to obtaining employer-sponsored health insurance. While Affordable Care Act provisions may mitigate insurance barriers for cancer survivors, many will still face cost barriers to affording health care without employer support. PMID:22717916

  19. An Exploratory Study of Employers' Attitudes Towards a Clinical Doctorate in Genetic Counseling.

    PubMed

    Valverde, Kathleen; Mueller, Rebecca; Paciotti, Breah; Conway, Laura

    2016-02-01

    Creation of an advanced degree in genetic counseling has been considered since the early 1980s. The Genetic Counseling Advanced Degree Task Force (GCADTF) was convened in 2012 to formally explore the potential suitability of a clinical doctorate (ClinD), though employer perspectives of advanced training were not part of the discussion. The conclusion of this group was that the field was not ready to move to an entry-level clinical doctorate at this time but that further education and research among other stakeholders was necessary (Nagy et al. 2014). In this study, we describe employers' perspectives on developing a clinical doctorate in genetic counseling based upon thirty audio-recorded semi-structured phone interviews that were transcribed verbatim and qualitatively analyzed. Overall, employers expressed concerns regarding the economic viability of ClinD training but envisioned expanded roles for genetic counselors (especially in areas of education and research) and enhanced credibility. While some employers reported that they would provide flexibility and tuition assistance for acquisition of a ClinD, for many employers, support was contingent on perceived value of the degree. Some employers were not clear about the difference between a ClinD and a PhD, suggesting that there is a need for educating employers about advanced degree options for the genetic counseling field. Future research could include investigating employer attitudes about market needs, envisioned roles, and compensation formulas for counselors with a ClinD or other forms of advanced training.

  20. Balancing flexibility for the employer and the employee: a case study of the development of annualized hours employment contracts.

    PubMed

    Tucker, P; Gaertner, J; Mason, C

    2001-12-01

    As with many forms of flexible working, Annualized Hours (AH) systems offer potential benefits to both the employer and the employee. However, the flexibility requirements of employers and employees often conflict. Therefore, when a large food manufacturing organization decided to redesign its AH system, it employed an independent consultancy to act as neutral third party. The consultancy provided technical expertise and assistance in developing an AH system that optimised productivity and was acceptable to the workforce. Data are presented, obtained from focus groups conducted throughout the organization, describing some of the potential difficulties of implementing an AH system. Drawing upon these data, a number of new AH systems were proposed and modelled using specialist software tools. The design process is described, together with the advantages and difficulties associated with use of the software tools. It is concluded that the key elements in the process of designing AH systems are centred around issues of trust and communication; the involvement of a broad range of interested parties, through a process of carefully managed group facilitation; and the need for adequate technical support in the development and evaluation of AH systems.

  1. Bioconcentration, biotransformation and elimination of pyrene in the arctic crustacean Gammarus setosus (Amphipoda) at two temperatures.

    PubMed

    Carrasco-Navarro, V; Jæger, I; Honkanen, J O; Kukkonen, J V K; Carroll, JoLynn; Camus, Lionel

    2015-09-01

    The influence of temperature on the bioaccumulation, toxicokinetics, biotransformation and depuration of pyrene was studied in the arctic marine amphipod Gammarus setosus. A two-compartment model was used to fit experimental values of total body burden, total metabolites and parent pyrene concentrations and to calculate toxicokinetic variables derived for two experimental treatments (2 and 8 °C). No statistically significant differences were observed with temperature for these toxicokinetic variables or bioconcentration factors. Contrarily, the Q10 values suggested that the toxicokinetic variables ke and km were temperature-dependent. This may be explained by the high standard deviation of the Q10 values. Q10 is the variation in the rate of a metabolic reaction with a 10 °C increase in temperature. Depuration rate constants were calculated from linear best fit equations applied to measured pyrene concentrations over time during the depuration phase of the experiment. During depuration, the parent pyrene was eliminated in two stages with faster elimination observed at 8 °C compared to 2 °C. This finding was also indicated by the Q10. No changes in total body burdens of metabolite concentrations were observed during the monitoring of depuration over a period of 96 h. The biotransformation pathway of pyrene in G. setosus was also investigated in this study with two main phase II biotransformation products discovered by liquid chromatography. These products are conditionally identified as the sulphate and glucose conjugates of 1-hydroxy-pyrene. Overall, the study contributes new knowledge to the understanding of the fate of PAHs in arctic biota. In particular, the study provides valuable insight into the bioaccumulation and biotransformation of an important PAH and its metabolites in a species that serves as both a predator and prey in the arctic ecosystem.

  2. Deriving bioconcentration factors and somatic biotransformation rates from dietary bioaccumulation and depuration tests.

    PubMed

    Gobas, Frank A P C; Lo, Justin C

    2016-12-01

    The present study develops, applies, and tests a method for deriving empirical bioconcentration factors and somatic biotransformation rate constants from dietary bioaccumulation tests and simplified bioaccumulation experiments that measure depuration rates. In this approach, measurement of the chemical concentration in the water is not required. The method aims to improve bioaccumulation assessment, reduce cost and animal use, and shorten experiments. Environ Toxicol Chem 2016;35:2968-2976. © 2016 SETAC.

  3. Biotransformation of RDX and HMX by Anaerobic Granular Sludge with Enriched Sulfate and Nitrate.

    PubMed

    An, Chunjiang; Shi, Yarong; He, Yanling; Huang, Guohe; Liu, Yonghong; Yang, Shucheng

    2017-05-01

      RDX and HMX are widely used energetic materials and they are recognized as environmental contaminants at numerous locations. The present study investigated the biotransformation of RDX and HMX by anaerobic granular sludge under sulfate- and nitrate-enriched conditions. The results showed that RDX and HMX could be transformed by anaerobic granular sludge when nitrate was present. However, the biotransformation of RDX and HMX was negatively influenced, especially with high nitrate concentrations. Sulfate-enriched conditions were more favorable for the removal of ammunition compounds by anaerobic granular sludge than nitrate-enriched conditions. The removal of RDX and HMX under both nitrate- and sulfate-enriched conditions was facilitated by the use of glucose as additional substrate. This knowledge may help identify factors required for rapid removal of RDX and HMX in high-rate bioreactors. These results can also be applied to devise an appropriate and practical biological treatment strategy for explosive contaminated wastewater.

  4. Modulation of porcine biotransformation enzymes by anthelmintic therapy with fenbendazole and flubendazole.

    PubMed

    Savlík, M; Fimanová, K; Szotáková, B; Lamka, J; Skálová, L

    2006-06-01

    Fenbendazole (FEN) and flubendazole (FLU) are benzimidazole anthelmintics often used in pig management for the control of nematodoses. The in vivo study presented here was designed to test the influence of FLU and FEN on cytochrome P4501A and other cytochrome P450 (CYP) isoforms, UDP-glucuronosyl transferase and several carbonyl reducing enzymes. The results indicated that FEN (in a single therapeutic dose as well as in repeated therapeutic doses) caused significant induction of pig CYP1A, while FLU did not show an inductive effect towards this isoform. Some of the other hepatic and intestinal biotransformation enzymes that were assayed were moderately influenced by FEN or FLU. Strong CYP1A induction following FEN therapy in pigs may negatively affect the efficacy and pharmacokinetics of FEN itself or other simultaneously or consecutively administered drugs. From the perspective of biotransformation enzyme modulation, FLU would appear to be a more convenient anthelmintic therapy of pigs than FEN.

  5. Self-employment as a solution for attitudinal barriers: a case study.

    PubMed

    Quinton, Melanie C

    2014-01-01

    This paper uses a case study to examine attitudinal barriers to employment and underemployment. We follow the career path of PR, a woman with multiple physical impairments, as she seeks financial independence through several employment strategies. In these, she faced attitudinal barriers and employment situations without opportunity for advancement. Eventually, PR opens her own business, turning to an alternative loan program to acquire the funds necessary to purchase a ready-made vehicle that matches her needs for accessible transportation. Use of this vehicle to provide delivery services for her business has more than doubled her income.

  6. Biotransformation of herbicides by aquatic microbial communities associated to submerged leaves.

    PubMed

    Carles, Louis; Rossi, Florent; Joly, Muriel; Besse-Hoggan, Pascale; Batisson, Isabelle; Artigas, Joan

    2017-02-01

    Leaf microbial communities possess a large panel of enzymes permitting the breakdown of leaf polymers as well as the transformation of organic xenobiotic compounds present in stream waters. This study aims to assess the potential of leaf microbial communities, exhibiting different exposure histories to pesticides (upstream versus downstream), to biotransform three maize herbicides (mesotrione, S-metolachlor, and nicosulfuron) in single and cocktail molecule exposures. The results showed a high dissipation of nicosulfuron (sulfonylurea herbicide) (from 29.1 ± 10.8% to 66 ± 16.2%, day 40) in both single and cocktail exposures, respectively, but not of mesotrione and S-metolachlor. The formation of nicosulfuron metabolites such as ASDM (2-(aminosulfonyl)-N,N-dimethyl-3-pyridinecarboxamide) and ADMP (2-amino-4,6-dimethoxypyrimidine) and the weak sorption (<0.4%) on the leaf matrix confirmed the transformation of this molecule by leaf microorganisms. In addition, the downstream communities showed a greater ability to transform nicosulfuron than the upstream communities suggesting that the exposure history to pesticides is an important parameter and can enhance the biotransformation potential of leaf microorganisms. After 40-day single exposure to nicosulfuron, the downstream communities were also those experiencing the greatest shifts in fungal and bacterial community diversity suggesting a potential adaptation of microorganisms to this herbicide. Our study emphasizes the importance of leaf microbial communities for herbicide biotransformation in polluted stream ecosystems where fungi could play a crucial role.

  7. Biotransformation effect of Bombyx Mori L. may play an important role in treating diabetic nephropathy.

    PubMed

    Zhang, Lei; Zhang, La; Li, Yin; Guo, Xin-Feng; Liu, Xu-Sheng

    2016-11-01

    Compared with herbal drugs, medicine processed from animals (animal medicine) was thought to have more bioactive substances and higher activities. Biotransformation effect often plays an important role in their effect. However, researches about effect of animal medicine on diabetic nephropathy and applying animal medicine as natural bio-transformer were seldom reported. The purpose of this paper was to reveal the use of Bombyx Mori L. on diabetic nephropathy from ancient to modern times. The classical literature indicated that Saosi Decoction (), which contains Bombyx Mori L. or silkworm cocoon, was applied to treat disorders congruent with modern disease diabetic nephropathy from the Ming to Qing Dynasty in ancient China. Modern studies showed that Bombyx Mori L. contains four main active constituents. Among these, 1-deoxynojirimycin (1-DNJ) and quercetin showed promising potential to be new agents in diabetic nephropathy treatment. The concentrations of 1-DNJ and the activities of quercetin in Bombyx Mori L. are higher than in mulberry leaves, because of the biotransformation in the Bombyx Mori L. body. However, these specifific components need further human and mechanistic studies to determine their therapeutic potential for this challenging condition.

  8. Employer-sponsored health insurance coverage limitations: results from the Childhood Cancer Survivor Study.

    PubMed

    Kirchhoff, Anne C; Kuhlthau, Karen; Pajolek, Hannah; Leisenring, Wendy; Armstrong, Greg T; Robison, Leslie L; Park, Elyse R

    2013-02-01

    The Affordable Care Act (ACA) will expand health insurance options for cancer survivors in the USA. It is unclear how this legislation will affect their access to employer-sponsored health insurance (ESI). We describe the health insurance experiences for survivors of childhood cancer with and without ESI. We conducted a series of qualitative interviews with 32 adult survivors from the Childhood Cancer Survivor Study to assess their employment-related concerns and decisions regarding health insurance coverage. Interviews were performed from August to December 2009 and were recorded, transcribed, and content analyzed using NVivo 8. Uninsured survivors described ongoing employment limitations, such as being employed at part-time capacity, which affected their access to ESI coverage. These survivors acknowledged they could not afford insurance without employer support. Survivors on ESI had previously been denied health insurance due to their preexisting health conditions until they obtained coverage through an employer. Survivors feared losing their ESI coverage, which created a disincentive to making career transitions. Others reported worries about insurance rescission if their cancer history was discovered. Survivors on ESI reported financial barriers in their ability to pay for health care. Childhood cancer survivors face barriers to obtaining ESI. While ACA provisions may mitigate insurance barriers for cancer survivors, many will still face cost barriers to affording health care without employer support.

  9. Biotransformation of bisphenol F by human and rat liver subcellular fractions.

    PubMed

    Cabaton, Nicolas; Zalko, Daniel; Rathahao, Estelle; Canlet, Cécile; Delous, Georges; Chagnon, Marie-Christine; Cravedi, Jean-Pierre; Perdu, Elisabeth

    2008-10-01

    Bisphenol F [4,4'-dihydroxydiphenyl-methane] (BPF) has a broad range of applications in industry (liners lacquers, adhesives, plastics, coating of drinks and food cans). Free monomers of this bisphenol can be released into the environment and enter the food chain, very likely resulting in the exposure of humans to low doses of BPF. This synthetic compound has been reported to be estrogenic. A study of BPF distribution and metabolism in rats has demonstrated the formation of many metabolites, with multiple biotransformation pathways. In the present work we investigated the in vitro biotransformation of radio-labelled BPF using rat and human liver subcellular fractions. BPF metabolites were separated, isolated by high-performance liquid chromatography (HPLC), and analysed by mass spectrometry (MS), MS(n), and nuclear magnetic resonance (NMR). Many of these metabolites were characterized for the first time in mammals and in humans. BPF is metabolised into the corresponding glucuronide and sulfate (liver S9 fractions). In addition to these phase II biotransformation products, various hydroxylated metabolites are formed, as well as structurally related apolar metabolites. These phase I metabolic pathways are dominant for incubations carried out with liver microsomes and also present for incubations carried out with liver S9 fractions. The formation of the main metabolites, namely meta-hydroxylated BPF and ortho-hydroxylated BPF (catechol BPF) is P450 dependent, as is the formation of the less polar metabolites characterized as BPF dimers. Both the formation of a catechol and of dimeric metabolites correspond to biotransformation pathways shared by BPF, other bisphenols and estradiol.

  10. Zebrafish embryo toxicity of anaerobic biotransformation products from the insensitive munitions compound 2,4-dinitroanisole.

    PubMed

    Olivares, Christopher I; Sierra-Alvarez, Reyes; Abrell, Leif; Chorover, Jon; Simonich, Michael; Tanguay, Robert L; Field, Jim A

    2016-11-01

    2,4-Dinitroanisole (DNAN) is an emerging insensitive munitions compound that readily undergoes anaerobic nitro-group reduction to 2-methoxy-5-nitroaniline (MENA) and 2,4-diaminoanisole (DAAN), followed by formation of unique azo dimers. Currently there is little knowledge on the ecotoxicity of DNAN (bio)transformation products. In the present study, mortality, development, and behavioral effects of DNAN (bio)transformation products were assessed using zebrafish (Danio rerio) embryos. The authors tested individual products, MENA and DAAN, as well as dimer and trimer surrogates. As pure compounds, 3-nitro-4-methoxyaniline and 2,2'-dimethoxy-4,4'-azodianiline caused statistically significant effects, with lowest-observable-adverse effect levels (LOAEL) at 6.4 μM on 1 or 2 developmental endpoints, respectively. The latter had 6 additional statistically significant developmental endpoints with LOAELs of 64 μM. Based on light-to-dark swimming behavioral tests, DAAN (640 μM) caused reduction in swimming, suggestive of neurotoxicity. No statistically significant mortality occurred (≤64 μM) for any of the individual compounds. However, metabolite mixtures formed during different stages of MENA (bio)transformation in soil were characterized using high-resolution mass spectrometry in parallel with zebrafish embryo toxicity assays, which demonstrated statistically significant mortality during the onset of azo-dimer formation. Overall the results indicate that several DNAN (bio)transformation products cause different types of toxicity to zebrafish embryos. Environ Toxicol Chem 2016;35:2774-2781. © 2016 SETAC. © 2016 SETAC.

  11. The influence of social capital on employers' use of occupational health services: a qualitative study.

    PubMed

    Ståhl, Christian; Åborg, Carl; Toomingas, Allan; Parmsund, Marianne; Kjellberg, Katarina

    2015-10-23

    Occupational health services may have a strategic role in the prevention of sickness absence, as well as in rehabilitation and return to work after sick leave, because of their medical expertise in combination with a close connection to workplaces. The purpose of this study was to explore how employers and occupational health service providers describe their business relations and the use of occupational health services in rehabilitation in relation to the organization of such services. The study uses a theoretical framework based on social capital to analyse the findings. Interviews and focus groups with managers with Swedish public employers (n = 60), and interviews with occupational health services professionals (n = 25). Employers emphasized trustful relationships, local workplace knowledge, long-term contracts and dialogue about services for good relationships with occupational health providers. Occupational health providers strove to be strategic partners to employers, promoting preventive work, which was more easily achieved in situations where the services were organized in-house. Employers with outsourced occupational health services expressed less trust in their providers than employers with internal occupational health provision. Social capital emerges as central to understanding the conditions for cooperation and collective action in the use of occupational health services, with reference to structural (e.g. contracts), relational (e.g. trust) as well as cognitive (e.g. shared vision) dimensions. The study suggests that attention to the quality of relationships is imperative for developing purposeful occupational health service delivery in rehabilitation and return to work.

  12. Who opts for self-employment after retirement? A longitudinal study in the Netherlands.

    PubMed

    van Solinge, Hanna

    2014-09-01

    Self-employment among older age groups is rising. A better understanding of the role of self-employment in extending the working lives of individuals is, therefore, relevant from a policy perspective. By bridging the gap in the literature on work/retirement decision-making and entrepreneurship, the present study examines the factors associated with entry into self-employment post-retirement, after a worker has left a regular salaried position. This decision is modelled as a choice between full retirement and prolonged labour force participation, in the form of either a typical wage-providing job or self-employment. Data were derived from the Netherlands Interdisciplinary Demographic Institute Work and Retirement Panel, an ongoing longitudinal survey of older workers (50 years and over) employed by three private sector organisations and employed as civil servants in the Netherlands. These data were then analysed using multinomial logistic regression analysis. The results of this study show that the decision to pursue self-employment is primarily taken by retirees with relatively high levels of financial and human capital (wealth and educational attainment), those possessing entrepreneurial attitudes (high self-efficacy scores) and those who perceive their retirements to be completely involuntary. The results lend support to self-employment being selected as a postretirement path through opportunity rather than out of necessity. The fact that the retirements of the studied population were generally quite early, while not considered involuntary also suggests that the timing of the decision to retire may be driven by the emergence of new (business) opportunities.

  13. Importance of Mobile Genetic Elements and Conjugal Gene Transfer for Subsurface Microbial Community Adaptation to Biotransformation of Metals

    SciTech Connect

    Sorensen, Soren J.

    2005-06-01

    The overall goal of this project is to investigate the effect of mobile genetic elements and conjugal gene transfer on subsurface microbial community adaptation to mercury and chromium stress and biotransformation. Our studies focus on the interaction between the fate of these metals in the subsurface and the microbial community structure and activity.

  14. Biotransformation and recovery of the isoflavones genistein and daidzein from industrial antibiotic fermentations

    PubMed Central

    Weber, J. Mark; Reeves, Andrew R.; Seshadri, Ramya; Cernota, William H.; Gonzalez, Melissa C.; Gray, Danielle L.; Wesley, Roy K.

    2013-01-01

    The objective of this study was to follow the metabolic fate of isoflavone glucosides from the soybean meal in a model industrial fermentation to determine if commercially useful isoflavones could be harvested as coproducts from the spent broth at the end of the fermentation. The isoflavone aglycones, genistein and daidzein, together make up 0.1 - 0.2% of the soybean meal by weight but serve no known function in the manufacturing process. After feeding genistein to washed cells of the erythromycin-producing organism, Saccharopolyspora erythraea, the first biotransformation product (Gbp1) was determined by x-ray crystallography to be genistein-7-O-α-rhamnoside (rhamnosylgenistein). Subsequent feeding of rhamnosylgenistein to growing cells of S. erythraea led to the production of a second biotransformation product, Gbp2. Chromatographic evidence suggested that Gbp2 accumulated in the spent broth of the erythromycin fermentation. When the spent broth was hydrolyzed with acid or industrial enzyme preparations the isoflavone biotransformation products were returned back to their parental forms, genistein and daidzein, which were then recovered as coproducts. Desirable features of this method are that it does not require modification of the erythromycin manufacturing process or genetic engineering of the producing organism to be put into practice. A preliminary investigation of five additional antibiotic fermentations of industrial importance were also found to have isoflavone coproduct potential. PMID:23604533

  15. Biotransformation and recovery of the isoflavones genistein and daidzein from industrial antibiotic fermentations.

    PubMed

    Weber, J Mark; Reeves, Andrew R; Seshadri, Ramya; Cernota, William H; Gonzalez, Melissa C; Gray, Danielle L; Wesley, Roy K

    2013-07-01

    The objective of this study was to follow the metabolic fate of isoflavone glucosides from the soybean meal in a model industrial fermentation to determine if commercially useful isoflavones could be harvested as coproducts from the spent broth at the end of the fermentation. The isoflavone aglycones, genistein, and daidzein together make up 0.1-0.2 % of the soybean meal by weight but serve no known function in the manufacturing process. After feeding genistein to washed cells of the erythromycin-producing organism, Saccharopolyspora erythraea, the first biotransformation product (Gbp1) was determined by X-ray crystallography to be genistein-7-O-α-rhamnoside (rhamnosylgenistein). Subsequent feeding of rhamnosylgenistein to growing cells of Saccharopolyspora erythraea led to the production of a second biotransformation product, Gbp2. Chromatographic evidence suggested that Gbp2 accumulated in the spent broth of the erythromycin fermentation. When the spent broth was hydrolyzed with acid or industrial enzyme preparations, the isoflavone biotransformation products were returned back to their parental forms, genistein and daidzein, which were then recovered as coproducts. Desirable features of this method are that it does not require modification of the erythromycin manufacturing process or genetic engineering of the producing organism to be put into practice. A preliminary investigation of five additional antibiotic fermentations of industrial importance also found isoflavone coproduct potential.

  16. Fungus-mediated biotransformation of amorphous silica in rice husk to nanocrystalline silica.

    PubMed

    Bansal, Vipul; Ahmad, Absar; Sastry, Murali

    2006-11-01

    Rice husk is a cheap agro-based waste material, which harbors a substantial amount of silica in the form of amorphous hydrated silica grains. However, there have been no attempts at harnessing the enormous amount of amorphous silica present in rice husk and its room-temperature biotransformation into crystalline silica nanoparticles. In this study, we address this issue and describe how naturally deposited amorphous biosilica in rice husk can be bioleached and simultaneously biotransformed into high value crystalline silica nanoparticles. We show here that the fungus Fusarium oxysporum rapidly biotransforms the naturally occurring amorphous plant biosilica into crystalline silica and leach out silica extracellularly at room temperature in the form of 2-6 nm quasi-spherical, highly crystalline silica nanoparticles capped by stabilizing proteins; that the nanoparticles are released into solution is an advantage of this process with significant application and commercial potential. Calcination of the silica nanoparticles leads to loss of occluded protein and to an apparently porous structure often of cubic morphology. The room-temperature synthesis of oxide nanomaterials using microorganisms starting from potential cheap agro-industrial waste materials is an exciting possibility and could lead to an energy-conserving and economically viable green approach toward the large-scale synthesis of oxide nanomaterials.

  17. Manipulation of heterogeneity product in 4'-demethylepipodophyllotoxin biotransformation process by using yeast extract as nitrogen source.

    PubMed

    Zhao, Wei; Li, Hong-Mei; Wan, Duan-Ji; Tang, Ya-Jie

    2012-01-01

    Manipulation of product heterogeneity was attempted by using yeast extract as nitrogen source in Alternaria alternata S-f6 transformation process of 4'-demethylepipodophyllotoxin. When the nitrogen source of NaNO(3) was replaced by yeast extract, the heterogeneity of biotransformation products was significantly varied from a single product (i.e., 4'-demethylpodophyllotoxone) to four podophyllum derivates. According to the kinetics of 4'-demethylepipodophyllotoxin biotransformation process by A. alternata S-f6, the starting substrate of 4'-demethylepipodophyllotoxin was preferentially transformed to produce 4'-demethylpodophyllotoxone (1) with an oxidation reaction. By the further comparison of products configuration, 4β-caprinoyl-4'-demethylepipodophyllotoxin (3) was produced from 4'-demethylpodophyllotoxone (1) instead of 4'-demethylisopicropodophyllone (2), which might be produced from 4'-demethylpodophyllotoxone (1) with the isomerization of lactone. Finally, 4'-demethylisopicropodophyllone (2) was hydrolyzed to produce 3α-hydroxymethyl-(6, 7)-dioxol-4-one-naphthalene (4). This work shows new information on the 4'-demethylepipodophyllotoxin biotransformation process by A. alternata S-f6 and provides a foundation for further studies on the structural diversification of a bioactive natural lead compound.

  18. Bioaccumulation and biotransformation of pyrene and 1-hydroxypyrene by the marine whelk Buccinum undatum.

    PubMed

    Beach, Daniel G; Quilliam, Michael A; Rouleau, Claude; Croll, Roger P; Hellou, Jocelyne

    2010-04-01

    The fates of a phenolic contaminant and its hydrocarbon precursor have rarely been compared, especially in an invertebrate species. Two groups of Buccinum undatum were exposed to equimolar amounts of pyrene and 1-hydroxypyrene over 15 d through their diets. Tissue extracts from the muscle and visceral mass were analyzed by liquid chromatography with fluorescence and mass spectrometry detection. Nine biotransformation products were detected in animals from both exposures. These included 1-hydroxypyrene, pyrene-1-sulfate, pyrene-1-glucuronide, pyrene glucose sulfate, two isomers each of pyrenediol sulfate and pyrenediol disulfate, and one isomer of pyrenediol glucuronide sulfate. These compounds represent a more complex metabolic pathway for pyrene than is typically reported. Diconjugated metabolites were as important in animals exposed to pyrene as in those exposed to 1-hydroxypyrene. Biotransformation products represented >90% of the material detected in the animals and highlight the importance of analyzing metabolites when assessing exposure. A mean of only 2 to 3% of the body burden was present in muscle compared with the visceral mass of both groups. The analytical methods were sufficiently sensitive to detect biotransformation products both in laboratory control whelks and in those sampled offshore. The tissue distribution of [(14)C]pyrene was also studied by autoradiography. Radioactivity was present primarily in the digestive and excretory system of the whelks and not in the gonads or muscle tissue. (c) 2009 SETAC.

  19. Students' Perspectives on Term-Time Employment: An Exploratory Qualitative Study

    ERIC Educational Resources Information Center

    Robotham, David

    2013-01-01

    The number of full-time students engaging in part-time employment during their studies at university continues to rise, both in the UK and in other countries. The majority of previous studies in this area have adopted a quantitative research design, using a survey. Findings from such studies have tended to focus on demonstrating what students are…

  20. Maternal employment and early childhood overweight: findings from the UK Millennium Cohort Study

    PubMed Central

    Hawkins, Summer Sherburne; Cole, Tim J; Law, Catherine

    2009-01-01

    Background: In most developed countries, maternal employment has increased rapidly. Changing patterns of family life have been suggested to be contributing to the rising prevalence of childhood obesity. Objectives: Our primary objective was to examine the relationship between maternal and partner employment and overweight in children aged three years. Our secondary objective was to investigate factors related to early childhood overweight only among mothers in employment. Design: Cohort study Subjects: 13113 singleton children aged three years in the Millennium Cohort Study, born between 2000 and 2002 in the United Kingdom, who had complete height/weight data and parental employment histories. Measurements: Parents were interviewed when the child was aged 9 months and 3 years and the child's height and weight were measured at 3 years. Overweight (including obesity) was defined by the International Obesity Task Force cut-offs. Results: 23% (3085) of children were overweight at 3 years. Any maternal employment after the child's birth was associated with early childhood overweight (OR [95% CI]; 1.14 [1.00, 1.29]), after adjustment for potential confounding and mediating factors. Children were more likely to be overweight for every 10 hours a mother worked per week (OR [95% CI]; 1.10 [1.04, 1.17]), after adjustment. An interaction with household income revealed that this relationship was only significant for children from households with an annual income of £33,000 ($57,750) or higher. There was no evidence for an association between early childhood overweight and whether or for how many hours the partner worked or with mothers' or partners' duration of employment. These relationships were found to be stronger among mothers in employment. Independent risk factors for early childhood overweight were consistent with the published literature. Conclusions: Long hours of maternal employment rather than lack of money may impede young children's access to healthy foods and

  1. Spontaneous disclosure of BRCA1/2 genetic test results to employers: a French prospective study.

    PubMed

    Eisinger, François; Fabre, Roxane; Lasset, Christine; Stoppa-Lyonnet, Dominique; Julian-Reynier, Claire; Nogues, Catherine

    2012-09-01

    The aim of this study was to examine the patterns of disclosure of BRCA1/2 genetic test results to employers by unaffected carriers. In a national prospective cohort study on unaffected BRCA1/2 mutation carriers, disclosure to employers was assessed prospectively, using self-administered questionnaires, up to 2 years after their test results were delivered by cancer geneticists. Kaplan-Meier curves and Cox-regression analysis were used to assess the factors associated with time to disclosure to the employer. Mean age of the 146 women BRCA1/2 carriers who were employed when their test results were delivered was 37.1 years (range: 19-57). At the end of the second year of follow-up, 47 of them (32.2%) had disclosed their results to their employers; median time to disclosure was 6 months. Reasons spontaneously expressed were first to inform the employer that medical surveillance/surgery was necessary for cancer risk management although these carriers did not actually have cancer. After multivariate adjustment on age, women with a lower educational level (HRadj=2.00, P=0.026) and those who had undergone prophylactic surgery during the 2 years of follow-up (HRadj=2.18, P=0.019) had disclosed their BRCA status to their employers earlier and more frequently. One-third of the female carriers not affected by breast/ovarian cancer disclosed their BRCA1/2 genetic test results spontaneously to their employers, mainly to inform them that they were disease-free but required medical surveillance or a surgical intervention to reduce the risk of cancer.

  2. Maternal employment and early childhood overweight: findings from the UK Millennium Cohort Study.

    PubMed

    Hawkins, S S; Cole, T J; Law, C

    2008-01-01

    In most developed countries, maternal employment has increased rapidly. Changing patterns of family life have been suggested to be contributing to the rising prevalence of childhood obesity. Our primary objective was to examine the relationship between maternal and partner employment and overweight in children aged 3 years. Our secondary objective was to investigate factors related to early childhood overweight only among mothers in employment. Cohort study. A total of 13 113 singleton children aged 3 years in the Millennium Cohort Study, born between 2000 and 2002 in the United Kingdom, who had complete height/weight data and parental employment histories. Parents were interviewed when the child was aged 9 months and 3 years, and the child's height and weight were measured at 3 years. Overweight (including obesity) was defined by the International Obesity Task Force cut-offs. A total of 23% (3085) of children were overweight at 3 years. Any maternal employment after the child's birth was associated with early childhood overweight (odds ratio (OR) [95% confidence interval (CI)]; 1.14 [1.00, 1.29]), after adjustment for potential confounding and mediating factors. Children were more likely to be overweight for every 10 h a mother worked per week (OR [95% CI]; 1.10 [1.04, 1.17]), after adjustment. An interaction with household income revealed that this relationship was only significant for children from households with an annual income of pound33 000 ($57 750) or higher. There was no evidence for an association between early childhood overweight and whether or for how many hours the partner worked, or with mothers' or partners' duration of employment. These relationships were also evident among mothers in employment. Independent risk factors for early childhood overweight were consistent with the published literature. Long hours of maternal employment, rather than lack of money may impede young children's access to healthy foods and physical activity. Policies

  3. Anaerobic Biotransformation and Mobility of Pu and Pu-EDTA

    SciTech Connect

    Bolton, H., Jr.; Bailey, V.L.; Plymale, A.E.; Rai, D.; Xun, L.

    2006-04-05

    begun to enrich and isolate bacteria capable of aerobic and anaerobic degradation of EDTA. Environmental samples (e.g., sludges, river sediments) were incubated aerobically and anaerobically with EDTA or NTA as the sole carbon and energy source. Aerobic enrichment with EDTA has not resulted in any cultures, but NTA has provided several isolates. Partial 16S rRNA gene sequence and sequence comparison identified four separate strains closely related to Microbacterium oxydans, Aminobacter sp., Achromobacter sp., Aminobacter sp., respectively. Anaerobic enrichments with either EDTA or NTA are still in progress since metabolism and growth is relatively slow. In addition to the biotransformation experiments, studies are underway to determine/validate complexation constants of Pu(III) with EDTA and the influence of competing ions on Pu(III)-EDTA complexes. These data are being obtained through solubility studies of PuPO{sub 4}(s) and Pu(OH){sub 3}(s) as a function of time, pH, and EDTA and competing ion concentrations. These results have begun to fill-in knowledge gaps of how anaerobic conditions will influence Pu and Pu-EDTA fate and transport to assess, model, and design approaches to stop Pu transport in groundwater at DOE sites.

  4. Biotransformation and accumulation of arsenic in soil amended with seaweed.

    PubMed

    Castlehouse, Hayley; Smith, Cassandra; Raab, Andrea; Deacon, Claire; Meharg, Andrew A; Feldmann, Jörg

    2003-03-01

    For many coastal regions of the world, it has been common practice to apply seaweed to the land as a soil improver and fertilizer. Seaweed is rich in arsenosugars and has a tissue concentration of arsenic up to 100 micro/g g(-1). These arsenic species are relatively nontoxic to humans; however, in the environment they may accumulate in the soil and decompose to more toxic arsenic species. The aim of this study was to determine the fate and biotransformation of these arsenosugars in soil using HPLC-ICP-MS analysis. Data from coastal soils currently manured with seaweeds were used to investigate if arsenic was accumulating in these soils. Long-term application of seaweed increased arsenic concentrations in these soils up to 10-fold (0.35 mg of As kg(-1) for nonagronomic peat, 4.3 mg of As kg(-1) for seaweed-amended peat). The biotransformation of arsenic was studied in microcosm experiments in which a sandy (machair) soil, traditionally manured with seaweed, was amended with Laminaria digitata and Fucus vesiculosus. In both seaweed species, the arsenic occurs in the form of arsenosugars (85%). The application of 50 g of seaweed to 1 kg of soil leads to an increase of arsenic in the soils, and the dominating species found in the soil pore water were dimethylarsinic acid (DMA(V)) and the inorganic species arsenate (As(V)) and arsenite (As(III)) after the initial appearance of arsenosugars. A proposed decomposition pathway of arsenosugars is discussed in which the arsenosugars are transformed to DMA(V) and further to inorganic arsenic without appreciable amounts of methylarsonic acid (MA(V)). Commercially available seaweed-based fertilizers contain arsenic concentration between 10 and 50 mg kg(-1). The arsenic species in these fertilizers depends on the manufacturing procedure. Some contain mainly arsenosugars while others contain mainly DMA(V) and inorganic arsenic. With the application rates suggested by the manufacturers, the application of these fertilizers is 2

  5. Does cancer in a child affect parents' employment and earnings? A population-based study.

    PubMed

    Syse, Astri; Larsen, Inger Kristin; Tretli, Steinar

    2011-06-01

    Cancer in a child may adversely affect parents' work opportunities due to enlarged care burdens and/or altered priorities. Few studies exist, and possible effects on parental employment and earnings were therefore explored. Data on the entire Norwegian population aged 27-65 with children under the age of 20 in 1990-2002 (N=1.2 million) was retrieved from national registries. Employment rates for parents of 3263 children with cancer were compared to those of parents with children without cancer by means of logistic regression models. Log-linear regression models were used to explore childhood cancer's effect on parental earnings for the large majority of parents who remained employed. Cancer in a child was in general not associated with a reduced risk of employment, although some exceptions exist among both mothers and fathers. For employed mothers, CNS cancers, germinal cell cancers, and unspecified leukemia were associated with significant reductions in earnings (10%, 21%, and 60%, respectively). Reductions were particularly pronounced for mothers with a young and alive child, and became more pronounced with time elapsed from diagnosis. Fathers' earnings were not affected significantly. Parents' employment is not adversely affected by a child's cancer in Norway. Earnings are reduced in certain instances, but the overall effects are minor. Generous welfare options and flexible labor markets typical for Nordic welfare states may account for this. In line with traditional caregiving responsibilities, reductions in earnings were most pronounced for mothers. Copyright © 2010 Elsevier Ltd. All rights reserved.

  6. Microbial monooxygenase amperometric biosensor for monitoring of Baeyer-Villiger biotransformation.

    PubMed

    Schenkmayerová, Andrea; Bučko, Marek; Gemeiner, Peter; Katrlík, Jaroslav

    2013-12-15

    A whole-cell amperometric biosensor consisting of genetically engineered Escherichia coli immobilised in polyelectrolyte membrane onto a miniaturised oxygen electrode was developed and used for monitoring of biotransformation based on Baeyer-Villiger oxidation. Baeyer-Villiger oxidation is commonly performed using microorganisms overexpressing Baeyer-Villiger monooxygenase enabling the production of enantiopure lactones or esters used in pharmaceutical industry. The biorecognition element, genetically modified E. coli overexpressing either cyclopentanone monooxygenase or cyclohexanone monooxygenase was immobilised in the form of solid polyelectrolyte complex gel membrane made of cellulose sulphate, sodium alginate and poly(methylene-co-guanidine) and attached to the surface of miniaturised oxygen electrode. The time response of the biosensor was 30s, the linear range of the calibration curve (R(2)=0.9993) was 8-130 μM and the sensitivity was 1.8 nA μM(-1) (RSD=5.0%) for substrate of Baeyer-Villiger oxidation (±)-cis-bicyclo[3.2.0]hept-2-en-6-one as analyte. The biosensor sensitivity was assessed for two other commercially available substrates, 4-methylcyclohexanone and 3-methylcyclohexanone. No interferences from ampicillin, citric acid, acetic acid, ethanol, methanol, glucose and products of Baeyer-Villiger oxidation (1R, 5S)-3-oxabicyclo[3.3.0]oct-6-en-2-one and (1S, 5R)-2-oxabicyclo[3.3.0]oct-6-en-3-one were detected. After 1 week of storage at 4°C the biosensor sensitivity was without changes. The biosensor was employed for monitoring of Baeyer-Villiger biotransformation and the results were correlated with gas chromatography. Till now, this is the first described biosensor based on Baeyer-Villiger monooxygenase and the first reported application of biosensor for monitoring of biotransformation based on Baeyer-Villiger oxidation. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Biotransformation and nephrotoxicity of ochratoxin B in rats

    SciTech Connect

    Mally, Angela; Keim-Heusler, Heike; Amberg, Alexander; Kurz, Michael; Zepnik, Herbert; Mantle, Peter; Voelkel, Wolfgang; Hard, Gordon C.; Dekant, Wolfgang . E-mail: dekant@toxi.uni-wuerzburg.de

    2005-08-01

    Ochratoxin B (OTB), a secondary metabolite of Aspergillus ochraceus, is the nonchlorinated analogue of the mycotoxin ochratoxin A (OTA), which is one of the most potent renal carcinogens in rodents. Despite the closely related structure, OTB is considered to be of much lower toxicity. OTA is poorly metabolized and slowly eliminated, and this may play an important role in OTA toxicity, carcinogenicity, and organ specificity. Since little is known regarding biotransformation and renal toxicity of OTB, the aim of this study was to investigate biotransformation of OTB in rats and to characterize the nephrotoxicity and cytotoxicity of OTB. Male F344 rats were administered either a single dose of OTB (10 mg/kg bw) or repeated doses (2 mg/kg bw, 5 days/week for 2 weeks) and euthanized 72 h after the last dosing. In proximal tubule cells of animals treated with a single high dose of OTB, a slight increase in mitotic figures was observed, but no treatment-related changes were evident in clinical chemistry, in renal function, and histopathology after repeated administration. Excretion of OTB and metabolites in urine and feces was analyzed using both HPLC with fluorescence detection and LC-MS/MS. Ochratoxin beta, which results from cleavage of the peptide bond, was the major metabolite excreted in urine in addition to small amounts of 4-hydroxy-OTB. In total, 19% of the administered dose was recovered as OTB and ochratoxin beta in urine and feces within 72 h after a single dose. In contrast to OTA, no tissue-specific retention of OTB was evident after single and repeated administration. In LLC-PK1 cells, a renal cell culture system that retains much of the specific features of the proximal tubule, only minor differences in the extent of cytotoxicity of OTA and OTB were observed. At low concentrations (< 25 {mu}M), treatment with OTA was slightly more toxic, whereas reduction in cell viability was similar at concentrations up to 100 {mu}M. In summary, these data suggest that

  8. Anaerobic Biotransformation and Mobility of Pu and Pu-EDTA

    SciTech Connect

    Bolton, H., Jr.; Rai, D.; Xun, L.

    2005-04-18

    The complexation of radionuclides (e.g., plutonium (Pu) and {sup 60}Co) by codisposed ethylenediaminetetraacetate (EDTA) has enhanced their transport in sediments at DOE sites. Our previous NABIR research investigated the aerobic biodegradation and biogeochemistry of Pu(IV)-EDTA. Plutonium(IV) forms stable complexes with EDTA under aerobic conditions and an aerobic EDTA degrading bacterium can degrade EDTA in the presence of Pu and decrease Pu mobility. However, our recent studies indicate that while Pu(IV)-EDTA is stable in simple aqueous systems, it is not stable in the presence of relatively soluble Fe(III) compounds (i.e., Fe(OH){sub 3}(s)--2-line ferrihydrite). Since most DOE sites have Fe(III) containing sediments, Pu(IV) in likely not the mobile form of Pu-EDTA in groundwater. The only other Pu-EDTA complex stable in groundwater relevant to DOE sites would be Pu(III)-EDTA, which only forms under anaerobic conditions. Research is therefore needed in this brand new project to investigate the biotransformation of Pu and Pu-EDTA under anaerobic conditions. The biotransformation of Pu and Pu-EDTA under various anaerobic regimes is poorly understood including the reduction kinetics of Pu(IV) to Pu(III) from soluble (Pu(IV)-EDTA) and insoluble Pu(IV) as PuO2(am) by metal reducing bacteria, the redox conditions required for this reduction, the strength of the Pu(III)-EDTA complex, how the Pu(III)-EDTA complex competes with other dominant anoxic soluble metals (e.g., Fe(II)), and the oxidation kinetics of Pu(III)-EDTA. Finally, the formation of a stable soluble Pu(III)-EDTA complex under anaerobic conditions would require degradation of the EDTA complex to limit Pu(III) transport in geologic environments. Anaerobic EDTA degrading microorganisms have not been isolated. These knowledge gaps preclude the development of a mechanistic understanding of how anaerobic conditions will influence Pu and Pu-EDTA fate and transport to assess, model, and design approaches to stop

  9. Employment among Spinal Cord Injured Patients Living in Turkey: A Cross-Sectional Study

    ERIC Educational Resources Information Center

    Gunduz, Berrin; Erhan, Belgin; Bardak, Ayse Nur

    2010-01-01

    The aim of this study was to determine the rate of employment and to establish the factors affecting vocational status in spinal cord injured patients living in Turkey. One hundred and fifty-two traumatic spinal cord injured patients older than 18 years with injury duration of at least 1 year and living in the community were included in the study;…

  10. Involving Employers in Training: Case Studies. Research and Evaluation Report Series 97-J.

    ERIC Educational Resources Information Center

    Isbell, Kellie; Trutko, John W.; Barnow, Burt S.; Nightengale, Demetra; Pindus, Nancy

    This document contains in-depth descriptions and assessments of 17 exemplary employer-based training (EBT) programs that were studied as part of an examination of EBT programs. The case studies are based on site visits to each firm, during which interviews were conducted with company management, supervisors of workers in training, individuals…

  11. Comparative Study of Vocational Nursing Curriculum and Employer Requirements. October 1989-September 1990.

    ERIC Educational Resources Information Center

    Zylinski, Doris; McMahon, Barbara

    To create the foundation for the development of a model curriculum for the 1990's for the training of Licensed Vocational Nurses (LVN), Napa Valley college conducted a statewide study comparing vocational nursing program curricula with employer requirements. To assist the study, an advisory committee was established, which included practicing…

  12. The Impact of Adolescent Stuttering on Educational and Employment Outcomes: Evidence from a Birth Cohort Study

    ERIC Educational Resources Information Center

    McAllister, Jan; Collier, Jacqueline; Shepstone, Lee

    2012-01-01

    Purpose: In interview and survey studies, people who stutter report the belief that stuttering has had a negative impact on their own education and employment. This population study sought objective evidence of such disadvantage for people who stutter as a group, compared with people who do not stutter. Method: A secondary analysis of a British…

  13. Cancer, Employment, and American Indians: A Participatory Action Research Pilot Study

    ERIC Educational Resources Information Center

    Johnson, Sharon R.; Finifrock, DeAnna; Marshall, Catherine A.; Jaakola, Julia; Setterquist, Janette; Burross, Heidi L.; Hodge, Felicia Schanche

    2011-01-01

    American Indian cancer survivors are an underserved and understudied group. In this pilot study we attempted to address, through participatory action research, missing information about those factors that serve to either facilitate employment or hinder it for adult cancer survivors. One task of the study was to develop and/or modify…

  14. A Basis for Choice. Report of a Study Group on Post-16 Pre-Employment Courses.

    ERIC Educational Resources Information Center

    Further Education Curriculum Review and Development Unit, London (England).

    This report presents the findings of a study group that examined full-time pre-employment courses available in England and Wales for young people over 16 years of age. Part 1 sets forth the group's objectives. Part 2 focuses on the procedures used to fulfill the study group's task of examining existing courses to determine whether they enhance…

  15. A Study of Metacognitive Strategies Employed by English Listeners in an EFL Setting

    ERIC Educational Resources Information Center

    Yang, Chunmei

    2009-01-01

    This paper presents a study on the metacognitive strategies employed by English listeners in an EFL setting. The results of the study reveal that the subjects used directed attention most frequently and they used monitoring least frequently. Besides, there are differences in the use of metacognitive strategies between successful and unsuccessful…

  16. Comparative Study of Vocational Nursing Curriculum and Employer Requirements. October 1989-September 1990.

    ERIC Educational Resources Information Center

    Zylinski, Doris; McMahon, Barbara

    To create the foundation for the development of a model curriculum for the 1990's for the training of Licensed Vocational Nurses (LVN), Napa Valley college conducted a statewide study comparing vocational nursing program curricula with employer requirements. To assist the study, an advisory committee was established, which included practicing…

  17. The Impact of Adolescent Stuttering on Educational and Employment Outcomes: Evidence from a Birth Cohort Study

    ERIC Educational Resources Information Center

    McAllister, Jan; Collier, Jacqueline; Shepstone, Lee

    2012-01-01

    Purpose: In interview and survey studies, people who stutter report the belief that stuttering has had a negative impact on their own education and employment. This population study sought objective evidence of such disadvantage for people who stutter as a group, compared with people who do not stutter. Method: A secondary analysis of a British…

  18. Employer Sanctions and the Question of Discrimination: The GAO Study in Perspective.

    ERIC Educational Resources Information Center

    Briggs, Vernon M., Jr.

    1990-01-01

    Examines the study by the U.S. General Accounting Office (GAO) on the implementation of the employer sanctions requirement of the Immigration Reform and Control Act of 1986 (IRCA). Discusses citizenship discrimination and other possible discriminatory influences. Applauds the study's contribution while urging attention to omitted issues such as…

  19. Employment among Spinal Cord Injured Patients Living in Turkey: A Cross-Sectional Study

    ERIC Educational Resources Information Center

    Gunduz, Berrin; Erhan, Belgin; Bardak, Ayse Nur

    2010-01-01

    The aim of this study was to determine the rate of employment and to establish the factors affecting vocational status in spinal cord injured patients living in Turkey. One hundred and fifty-two traumatic spinal cord injured patients older than 18 years with injury duration of at least 1 year and living in the community were included in the study;…

  20. What We Learned about Mentoring Research Assistants Employed in a Complex, Mixed-Methods Health Study

    ERIC Educational Resources Information Center

    Weeks, Lori E.; Villeneuve, Michelle A.; Hutchinson, Susan; Roger, Kerstin; Versnel, Joan; Packer, Tanya

    2015-01-01

    We investigated the experiences of research assistants in their dual role as both employees and trainees, when they were employed in a complex, mixed-methods, Canadian study on the everyday experience of living with and managing a chronic condition. A total of 13 research assistants participated in one or more components of this study: a survey (n…

  1. Methodological Appendix of Research Methods Employed in the Mexican American Education Study.

    ERIC Educational Resources Information Center

    Commission on Civil Rights, Washington, DC.

    The U.S. Commission on Civil Rights released Mexican American Education Study findings in a series of documents: (1) "The Ethnic Isolation of Mexican Americans in the Public Schools of the Southwest" (ED 052 849), "The Unfinished Education" (ED 056 821), and "The Excluded Student" (ED 062 069). The research methods employed in the study are…

  2. Higher Education and Employment: The Changing Relationship. Recent Developments in Continuing Professional Education. Country Study: Yugoslavia.

    ERIC Educational Resources Information Center

    Savicevic, Dusan; Jovanovic, Goran

    This report, one of a series of country studies on higher education and employment particularly in continuing professional education, contains two papers on recent developments in Yugoslavia. The first presents the findings of a study of continuing professional education at Belgrade University in Serbia and at Titograd University in Montenegro.…

  3. Taskforce on Rural and Remote Education, Training, Employment and Children's Services: National Case Studies.

    ERIC Educational Resources Information Center

    Ministerial Council on Education, Employment, Training and Youth Affairs, Carlton South (Australia).

    This report presents synopses of case studies highlighting workable local strategies to improve employment, education, training, and children's services in rural and remote Australia. Common features of each study include a description of the local context, the targeted group for each program, significant features, sustainability factors, major…

  4. Cancer, Employment, and American Indians: A Participatory Action Research Pilot Study

    ERIC Educational Resources Information Center

    Johnson, Sharon R.; Finifrock, DeAnna; Marshall, Catherine A.; Jaakola, Julia; Setterquist, Janette; Burross, Heidi L.; Hodge, Felicia Schanche

    2011-01-01

    American Indian cancer survivors are an underserved and understudied group. In this pilot study we attempted to address, through participatory action research, missing information about those factors that serve to either facilitate employment or hinder it for adult cancer survivors. One task of the study was to develop and/or modify…

  5. Working to Live: Why University Students Balance Full-Time Study and Employment

    ERIC Educational Resources Information Center

    Holmes, Valerie

    2008-01-01

    Purpose: The aim of this study is to investigate why students work during their degree programme, what influences their choice of employment and to examine students' perception of their ability to balance work and study. Design/methodology/approach: A questionnaire was completed by 42 first- and second-year students from a single degree programme…

  6. The Federal Work-Study Program: Impacts on Academic Outcomes and Employment. CAPSEE Policy Brief

    ERIC Educational Resources Information Center

    Center for Analysis of Postsecondary Education and Employment, 2015

    2015-01-01

    Policymakers may be interested in the extent to which Federal Work-Study programs (FWS) increase students' access to productive employment, and how they impact students' academic and career success. This brief summarizes findings from a recent study using national data and a propensity score matching approach to examine the overall effects of FWS…

  7. Biotransformation of ferulic acid to 4-vinylguaiacol by a wild and a diploid strain of Aspergillus niger.

    PubMed

    Baqueiro-Peña, Itzamná; Rodríguez-Serrano, Gabriela; González-Zamora, Eduardo; Augur, Christopher; Loera, Octavio; Saucedo-Castañeda, Gerardo

    2010-06-01

    Ferulic acid biotransformation has a number of interesting industrial uses. Ferulic acid biotransformation by the wild strain Aspergillus niger C28B25 and a diploid strain DAR2, obtained by parasexual recombination, was studied. The wild strain of A.niger C28B25 biotransforms ferulic acid to vanillic acid (VA); while the diploid strain DAR2 preferentially decarboxylates ferulic acid to 4-vinylguaiacol (4VG). The latter was identified by mass spectroscopy, (1)H and (13)C nuclear magnetic resonance spectroscopy, and quantified by HPLC. The diploid strain A.niger DAR2 and the wild strain showed a ferulic acid conversion of 64% and 36%, respectively. Molar yields show that the formation of 4VG was preferred, being as much as 4.4 times higher than the formation of VA in diploid strain cultures. Differential regulation of enzymes involved in the biotransformation of ferulic acid may explain the accumulation of 4VG by diploid DAR2. This strain produced both 4VG and VA. (c) 2010 Elsevier Ltd. All rights reserved.

  8. Selection from fixed term to permanent employment: prospective study on health, job satisfaction, and behavioural risks

    PubMed Central

    Virtanen, M; Kivimaki, M; Elovainio, M; Vahtera, J

    2002-01-01

    Study objective: To examine health, job satisfaction, and behavioural risks as antecedents of selection from fixed term to permanent employment. Design: Prospective cohort study of change in employment contract during a two year period. Self reported health, recorded sickness absence, job satisfaction, behavioural risks, demographics, and occupational characteristics were assessed at baseline. Setting: Hospital staff in two Finnish hospital districts. Participants: A cohort of 526 hospital employees (54 men, 472 women) aged 20 to 58 years with a fixed term job contract at baseline. Main results: During the follow up period, 137 became permanently employed. Men, employees in higher positions, full time workers, and those with five to eight years in the employ of the hospital were more likely to become permanently employed. After adjusting for these factors, obtaining a permanent job contract was predicted by self rated good health (odds ratio (OR) 3.90; 95% confidence intervals (CI) 1.34 to 11.36), non-caseness of psychological distress (OR 1.80; 95% CI 1.01 to 3.20), high job satisfaction (OR 1.86; CI 1.17 to 2.94), and non-sedentary life style (OR 2.64; CI 1.29 to 5.41), compared with the rest of the cohort. Conclusions: Investigation of fixed term employees yields new information about selective mechanisms in employment mobility. Good health seems to promote the chances for a fixed term employee to reach a better labour market status. These results correspond to earlier research on selective mechanisms in other forms of employment mobility and provide a partial explanation for the socioeconomic gradient of health. PMID:12177087

  9. Palomar College 1999-2000 Vocational Education Employer Study. Study Two in Series Two of the Vocational Education Employer Study of Palomar Graduates.

    ERIC Educational Resources Information Center

    Brown, Pamela L.; Barton, Michelle

    This survey, developed by the faculty, program administrators, and Institutional Research and Planning Department of Palomar College in California, addresses employer attitudes regarding their experiences with Palomar graduates. The survey items range from open-ended questions to requests for agreement with a particular statement. Palomar…

  10. [Biotransformation of mogroside III by human intestinal bacteria].

    PubMed

    Yang, Xiu Wei; Zhang, Jian Ye; Xu, Wei

    2007-12-18

    To investigate the biotransformation of mogroside III, one of the main chemical constituent in the fruits of Momordica grosvenori Swingle, by the crude enzymes of human intestinal bacteria, and determine the structure of biotransformation products and provide scientific basis for absorption evaluation of primary mogroside III in human intestine. The mogroside III was incubated with crude enzymes of human intestinal bacteria under the anaerobic environment and 37 degrees C condition to transform mogroside III. The biotransformation products were isolated and purified by silica gel column chromatography, and structurally determined by infra-red (IR) and nuclear magnetic resonance (NMR) spectrometry and mass spectroscopy (MS) techniques. Mogroside III was converted to mogroside II(A1) and mogrol by successive deglycosylation at C-3 of the glucosyl group and C-24 of the gentiobiosyl group. The human intestinal bacteria showed potent ability to transform mogroside III to release secondary glycoside mogroside II(A1) and aglycone mogrol.

  11. Disclosure of a mental health problem in the employment context: qualitative study of beliefs and experiences.

    PubMed

    Brohan, E; Evans-Lacko, S; Henderson, C; Murray, J; Slade, M; Thornicroft, G

    2014-09-01

    Aims. Decisions regarding disclosure of a mental health problem are complex and can involve reconciling conflicting needs and values. This article provides a qualitative account of the beliefs and experiences of mental health service users regarding disclosure in employment contexts. Methods. Total sample of 45 individuals were interviewed in two study phases. In phase one, semi-structured interviews were carried out with 15 mental health service users. The transcripts were analysed using interpretative phenomenological analysis (IPA). In phase two, identified themes were further explored through interviews with mental health service users (n = 30) in three employment contexts: in paid employment (n = 10); in study or voluntary work (n = 10); and currently unemployed (n = 10). These were analysed using directed content analysis. Results. Four super-ordinate themes were drawn from phase one analysis: (1) public understanding of mental health problems; (2) the employment context; (3) personal impact of labelling and (4) disclosure needs. These themes were reflective of the content of phase two interviews. Conclusions. Greater emphasis needs to be placed on considering the societal, employment and interpersonal influences which form the basis for disclosure beliefs and experiences.

  12. Employment outcomes among survivors of common cancers: the Symptom Outcomes and Practice Patterns (SOAPP) study

    PubMed Central

    Lee, J. W.; Sesto, M. E.; Buhr, K. A.; Cleeland, C. S.; Manola, J.; Wagner, L. I.; Chang, V. T. S.; Fisch, M. J.

    2013-01-01

    Introduction Risk factors for employment difficulties after cancer diagnosis are incompletely understood, and interventions to improve post-cancer employment remain few. New targets for intervention are needed. Methods We assessed a cohort of 530 nonmetastatic cancer patients (aged≤65 years, >6 months from diagnosis, off chemo- or radiotherapy) from the observational multi-site Symptom Outcomes and Practice Patterns study. Participants reported employment change, current employment, and symptoms. Groups were based on employment at survey (working full- or part-time versus not working) and whether there had been a change due to illness (yes versus no). The predictive power of symptom interference with work was evaluated for employment group (working stably versus no longer working). Race/ethnicity, gender, cancer type, therapy, and time since diagnosis were also assessed. Association between employment group and specific symptoms was examined. Results The cohort was largely non-Hispanic white (76 %), female (85 %), and diagnosed with breast cancer (75 %); 24 % reported a change in employment. On multivariable analysis, participants with at least moderate symptom interference were more likely to report no longer working than their less effected counterparts (odds ratio (OR)=8.0, 95 % CI, 4.2–15.4), as were minority participants compared with their non-Hispanic white counterparts (OR=3.2, 95 % CI, 1.8– 5.6). Results from the multiple regression model indicated the combination of fatigue (OR=2.3, 95 % CI, 1.1–4.7), distress (OR=3.9, 95 % CI, 1.7–9.0), and dry mouth (OR=2.6, 95 % CI, 1.1–6.2) together with race/ethnicity and time since diagnosis adequately predicted for employment group. Conclusions Our findings support the hypothesis that residual symptom burden affects post-cancer employment: Residual symptoms may be targets for intervention to improve work outcomes among cancer survivors. Implications for Cancer Survivors This analysis examines whether

  13. Biodegradation of nicotine by a novel nicotine-degrading bacterium, Pseudomonas plecoglossicida TND35 and its new biotransformation intermediates.

    PubMed

    Raman, Gurusamy; Mohan, KasiNadar; Manohar, Venkat; Sakthivel, Natarajan

    2014-02-01

    Tobacco wastes that contain nicotine alkaloids are harmful to human health and the environment. In the investigation, a novel nicotine-biodegrading bacterium TND35 was isolated and identified as Pseudomonas plecoglossicida on the basis of phenotypic, biochemical characteristics and 16S rRNA sequence homology. We have studied the nicotine biodegradation potential of strain TND35 by detecting the intermediate metabolites using an array of approaches such as HPLC, GC-MS, NMR and FT-IR. Biotransformation metabolites, N-methylmyosmine, 4-hydroxy-1-(3-pyridyl)-1-butanone (HPB) and other three new intermediate metabolites namely, 3,5-bis (1-methylpyrrolidin-2-yl) pyridine, 2,3-dihydro-1-methyl-5-(pyridin-3-yl)-1H-pyrrol-2-ol and 5-(pyridin-3-yl)-1H-pyrrol-2(3H)-one have been identified. Interestingly, these intermediate metabolites suggest that the strain TND35 employs a novel nicotine biodegradation pathway, which is different from the reported pathways of Aspergillus oryzae 112822, Arthrobacter nicotinovorans pAO1, Agrobacterium tumefaciens S33 and other species of Pseudomonas. The metabolite, HPB reported in this study can also be used as biochemical marker for tobacco related cancer studies.

  14. Biotransformation of trans-1-chloro-3,3,3-trifluoropropene (trans-HCFO-1233zd).

    PubMed

    Schmidt, Tobias; Bertermann, Rüdiger; Rusch, George M; Tveit, Ann; Dekant, Wolfgang

    2013-05-01

    trans-1-Chloro-3,3,3-trifluoropropene (trans-HCFO-1233zd) is a novel foam blowing and precision cleaning agent with a very low impact for global warming and ozone depletion. trans-HCFO-1233zd also has a low potential for toxicity in rodents and is negative in genotoxicity testing. The biotransformation of trans-HCFO-1233zd and kinetics of metabolite excretion with urine were assessed in vitro and in animals after inhalation exposures. For in vitro characterization, liver microsomes from rats, rabbits and humans were incubated with trans-HCFO-1233zd. Male Sprague Dawley rats and female New Zealand White rabbits were exposed to 2,000, 5,000 and 10,000ppm for 6h and urine was collected for 48h after the end of the exposure. Study specimens were analyzed for metabolites using (19)F NMR, LC-MS/MS and GC/MS. S-(3,3,3-trifluoro-trans-propenyl)-glutathione was identified as predominant metabolite of trans-HCFO-1233zd in all microsomal incubation experiments in the presence of glutathione. Products of the oxidative biotransformation of trans-HCFO-1233zd were only minor metabolites when glutathione was present. In rats, both 3,3,3-trifluorolactic acid and N-acetyl-(3,3,3-trifluoro-trans-propenyl)-l-cysteine were observed as major urinary metabolites. 3,3,3-Trifluorolactic acid was not detected in the urine of rabbits. Quantitation showed rapid excretion of both metabolites in both species (t1/2<6h) and the extent of biotransformation of trans-HCFO-1233zd was determined as approximately 0.01% of received dose in rabbits and approximately 0.002% in rats. trans-HCFO-1233zd undergoes both oxidative biotransformation and glutathione conjugation at very low rates. The low extent of biotransformation and the rapid excretion of metabolites formed are consistent with the very low potential for toxicity of trans-HCFO-1233zd in mammals.

  15. Exposure to temporary employment and job insecurity: a longitudinal study of the health effects.

    PubMed

    Virtanen, Pekka; Janlert, Urban; Hammarström, Anne

    2011-08-01

    This study analysed interactions between job insecurity and temporary employment and health. We tested the violation hypothesis (whether permanent employment increases the health risk associated with job insecurity) and the intensification hypothesis (whether temporary employment increases the health risk associated with job insecurity) in a longitudinal setting. Previous research on this topic is scarce and based on cross-sectional data. A population cohort (n=1071) was surveyed at age 30 and age 42. Exposure to temporary employment during this 12-year period was elicited with a job-time matrix and measured as the score of 6-month periods. Exposure to job insecurity was measured according to the perceived threat of unemployment. Health at follow-up was assessed as optimal versus suboptimal self-rated health, sleep quality and mental health. In addition to sociodemographics and baseline health, the analyses were adjusted for exposure to unemployment, non-employment and self-employment during the 12-year period. 26% of participants had been exposed to temporary employment. The effect of job insecurity on health was the same in the exposed and unexposed groups, that is the violation hypothesis was not supported. Non-significant interactions between the exposures and all health outcomes also indicated null findings regarding the intensification hypothesis. These findings suggest that perceived job insecurity can lead to adverse health effects in both permanent and temporary employees. Policies should aim to improve work-related well-being by reducing job insecurity. Efforts towards 'flexicurity' are important, but it is equally important to remember that a significant proportion of employees with a permanent contract experience job insecurity.

  16. Adverse childhood experiences, health, and employment: A study of men seeking job services.

    PubMed

    Topitzes, James; Pate, David J; Berman, Nathan D; Medina-Kirchner, Christopher

    2016-11-01

    The present study explored factors associated with barriers to current employment among 199 low-income, primarily Black American men seeking job services. The study took place in an urban setting located within the upper Midwest region of the U.S., where the problem of Black male joblessness is both longstanding and widespread. Recent research suggests that Black male joblessness regionally and nationally is attributable to myriad macro- and micro-level forces. While structural-level factors such as migration of available jobs, incarceration patterns, and racism have been relatively well-studied, less is known about individual-level predictors of Black male joblessness, which are inextricably linked to macro-level or structural barriers. This study therefore examined relations between adverse childhood experiences (ACEs), health-related factors, and employment-related problems. Participants faced both specific and cumulative childhood adversities at much higher rates than men from more economically advantaged contexts. In addition, the physical, behavioral, and mental health of the study participants were, according to self-report survey results, notably worse than that of the general population or alternative samples. Finally, results indicated that exposure to ACEs may have helped to undermine the men's ability to attain current employment and that drug problems along with depression symptoms helped explain the link between ACEs and employment barriers. Theoretical and practical implications of results are explored.

  17. In vitro to in vivo extrapolation of biotransformation rates for assessing bioaccumulation of hydrophobic organic chemicals in mammals.

    PubMed

    Lee, Yung-Shan; Lo, Justin C; Otton, S Victoria; Moore, Margo M; Kennedy, Chris J; Gobas, Frank A P C

    2017-07-01

    Incorporating biotransformation in bioaccumulation assessments of hydrophobic chemicals in both aquatic and terrestrial organisms in a simple, rapid, and cost-effective manner is urgently needed to improve bioaccumulation assessments of potentially bioaccumulative substances. One approach to estimate whole-animal biotransformation rate constants is to combine in vitro measurements of hepatic biotransformation kinetics with in vitro to in vivo extrapolation (IVIVE) and bioaccumulation modeling. An established IVIVE modeling approach exists for pharmaceuticals (referred to in the present study as IVIVE-Ph) and has recently been adapted for chemical bioaccumulation assessments in fish. The present study proposes and tests an alternative IVIVE-B technique to support bioaccumulation assessment of hydrophobic chemicals with a log octanol-water partition coefficient (KOW ) ≥ 4 in mammals. The IVIVE-B approach requires fewer physiological and physiochemical parameters than the IVIVE-Ph approach and does not involve interconversions between clearance and rate constants in the extrapolation. Using in vitro depletion rates, the results show that the IVIVE-B and IVIVE-Ph models yield similar estimates of rat whole-organism biotransformation rate constants for hypothetical chemicals with log KOW  ≥ 4. The IVIVE-B approach generated in vivo biotransformation rate constants and biomagnification factors (BMFs) for benzo[a]pyrene that are within the range of empirical observations. The proposed IVIVE-B technique may be a useful tool for assessing BMFs of hydrophobic organic chemicals in mammals. Environ Toxicol Chem 2017;36:1934-1946. © 2016 SETAC. © 2016 SETAC.

  18. Biotransformation of hop aroma terpenoids by ale and lager yeasts.

    PubMed

    King, Andrew J; Dickinson, J Richard

    2003-03-01

    Terpenoids are important natural flavour compounds, which are introduced to beer via hopping. It has been shown recently that yeasts are able to biotransform some monoterpene alcohols. As a first step towards examining whether yeasts are capable of altering hop terpenoids during the brewing of beer, we investigated whether they were transformed when an ale and lager yeast were cultured in the presence of a commercially available syrup. Both yeasts transformed the monoterpene alcohols geraniol and linalool. The lager yeast also produced acetate esters of geraniol and citronellol. The major terpenoids of hop oil, however, were not biotransformed. Oxygenated terpenoids persisted much longer than the alkenes.

  19. [Psychological contract in the light of flexible employment: The review of studies].

    PubMed

    Żołnierczyk-Zreda, Dorota

    Changing employment relations between employees and employers due to the increasing employment flexibility have contributed to the development of a new paradigm to analyze these relations based on the concept of psychological contract. This paradigm might be particularly relevant in Poland where the employment flexibility understood as the number of workers with temporary contracts is the highest in Europe. In this paper the concept of psychological contract is presented along with the existing findings related to its range, balance and contract fulfilment vs. contract breach. The results of studies showing the differences in psychological contract of temporary and permanent workers are also presented. The majority of them indicate that psychological contracts of temporary workers are limited in their extent, less balanced and asymmetric (to workers' disadvantage), as well as more transactional in their nature than those of permanent workers. The temporary workers' well-being and attitudes towards work and their reaction to psychological contract breach largely depends on their preferences for this type of employment, on their qualifications and on a labor market situation. Med Pr 2016;67(4):529-536. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  20. Biotransformation of p-coumaric acid by Paecilomyces variotii.

    PubMed

    Sachan, A; Ghosh, S; Mitra, A

    2006-01-01

    To investigate the biotransformation of p-coumaric acid into p-hydroxybenzoic acid (p-HBA) by Paecilomyces variotii Bainier MTCC 6581. As a result of p-coumaric acid degradation by P. variotii, three phenolic metabolites, p-hydroxybenzaldehyde (p-HBAld), p-HBA and protocatechuic acid were formed. These phenolics were detected using TLC and HPLC. The identity of p-HBA and p-HBAld was further confirmed by mass spectrometry. Various analyses showed that 10.0 mmol l(-1) concentration of p-coumaric acid produced a maximum amount of p-hydroxybenzoic acid, 200 mg l(-1), into the medium at 37 degrees C with high-density cultures. A catabolic pathway of p-coumaric acid by the fungus P. variotii is suggested for the first time. During the process of p-coumaric acid degradation, p-HBA accumulated in the medium as the major degradation product. Microbial degradation of cinnamic acid and hydroxycinnamic acid has continued to be the focus of intensive study. The main goal was to identify the microbial species capable of converting these substances into commercially value-added products such as benzoic acid derivatives or aromatic aldehydes.

  1. Rapidly directional biotransformation of tauroursodeoxycholic acid through engineered Escherichia coli.

    PubMed

    Shi, Jie; Wang, Jie; Yu, Lu; Yang, Li; Zhao, Shujuan; Wang, Zhengtao

    2017-03-22

    Bear bile powder is a precious medicinal material. It is characterized by high content of tauroursodeoxycholic acid (TUDCA) at a ratio of 1.0-1.5 to taurochenodeoxycholic acid (TCDCA). Here, we reported the biotransformation of tauroursodeoxycholic acid (TUDCA) through Escherichia coli engineered with a two-step mimic biosynthetic pathway of TUDCA from taurochenodeoxycholic acid (TCDCA). Two 7α-hydroxysteroid dehydrogenase (7α-HSDH) and two 7β-hydroxysteroid dehydrogenase (7β-HSDH) genes (named as α1, α2, β1, and β2) were selected and synthesized to create four pathway variants using ePathBrick. All could convert TCDCA to TUDCA and the one harboring α1 and β2 (pα1β2) showed the strongest capability. Utilizing the oxidative and reductive properties of 7α- and 7β-HSDH, an ideal balance between TUDCA and TCDCA was established by optimizing the fermentation conditions. By applying the optimal condition, E. coli containing pα1β2 (BL-pα1β2) produced up to 1.61 ± 0.13 g/L of TUDCA from 3.23 g/L of TCDCA at a ratio of 1.3 to TCDCA. This study provides a potential approach for bear bile substitute production from cheap and readily available chicken bile.

  2. Biotransformation of drospirenone, a contraceptive drug, with Cunninghamella elegans.

    PubMed

    Baydoun, Elias; Atia-Tul-Wahab; Iqbal, Sheeza; Smith, Colin; Choudhary, M Iqbal

    2017-10-01

    Biotransformation of an orally active contraceptive drug, drospirenone (1), by Cunninghamella elegans ATCC 36114 yielded four new metabolites, 6β,7β,15β,16β-dimethylene-3-oxo-14α-hydroxy-17α-pregn-4-ene-21,17-carbolactone (2), 6β,7β,15β,16β-dimethylene-3,11-dioxo-17α-pregn-4-ene-21,17-carbolactone (3), 6β,7β,15β,16β-dimethylene-3,12-dioxo-17α-pregn-4-ene-21,17-carbolactone (4), and 6β,7β,15β,16β-dimethylene-3-oxo-11β,14α-dihydroxy-17α-pregn-4-ene-21,17-carbolactone (5), along with a known metabolite, 6β,7β,15β,16β-dimethylene-3-oxo-11α-dihydroxy-17α-pregn-4-ene-21,17-carbolactone (6). This study provides not only new analogues of orally active contraceptive drug, drospirenone, but also help in understanding the metabolism of this important drug. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Employment status, social function decline and caregiver burden among stroke survivors. A South Indian study.

    PubMed

    Sreedharan, Sapna Erat; Unnikrishnan, J P; Amal, M G; Shibi, B S; Sarma, Sankara; Sylaja, P N

    2013-09-15

    Stroke leaves at least 60% of the survivors with moderate to severe disability limiting their employment status and social functioning leading to high levels of caregiver burden. We sought to study the employment status and level of change of social functioning of stroke survivors and their principal caregiver and correlate it with severity of stroke, functional disability, and anxiety and depression scores. One hundred and fifty stroke survivors and principal caregivers (3 months-2 years post-stroke) were recruited for the study. The employment status pre- and post-stroke was assessed. The social function of the patient and caregiver was analyzed using a 6 item social function scale developed for the study, encompassing culturally relevant questions. A 20 point scale adapted from Burden assessment schedule was used to assess the caregiver burden. Mean age of the study group was 54.37±12.072 (range 22-75 years), with 116 males and 34 females. Spouse was the principal caregiver for 142/150 patients (94.6%). In the stroke survivors, compared to the pre-stroke employment status of 62.7%, only 20.7% were employed post-stroke with half having change of job. But the employment status of caregiver was not reduced post-stroke (34.7% vs 33.3%). Employment loss in stroke survivors had a statistically significant association with severity of functional disability, male gender and presence of limb weakness (p values 0.037, 0.0001 and 0.043 respectively). There was an overall decline in social functions among the 6 parameters assessed in both the stroke survivors and caregivers. Of the caregiver burden, financial burden was more among female and older caregivers. The functional status and motor weakness of the stroke survivors did not tend to worsen the overall caregiver burden. Loss of occupation among stroke survivors is high. The decline in social function among stroke survivors and caregivers was significant. Even though functional disability contributed to employment loss

  4. Applying a Schema for Studying the Instructive Techniques Employed by Authors of Four Novels for Adolescents.

    ERIC Educational Resources Information Center

    Severin, Mary Susan

    The purpose of this study was to apply a schema to adolescent novels, to determine what lessons the authors teach and what techniques they employ in their teaching. A historical review of literary criticism established a background for interpreting the educational function of literature. A schema of questions based on the historical background was…

  5. Multidimensional Typology of Rural Communities as a Means of Studying Employment Structure.

    ERIC Educational Resources Information Center

    Zaslavskaia, Tatiana Ivanovna; And Others

    The prediction, planning and management of the social development of a rural region presupposed typologization of its communities. This study aimed to: build an overall social typology of the rural communities in Siberia; elucidate the role of employment structure among other type-forming factors of social differentiation; build a special typology…

  6. An Empirical Study of the Influence of the Concept of "Job-Hunting" on Graduates' Employment

    ERIC Educational Resources Information Center

    Chen, Chengwen; Hu, Guiying

    2008-01-01

    The concept of job-hunting is an important factor affecting university students' employment. This empirical study shows that while hunting for a job, graduates witness negative correlation between their expectation of the nature of work and the demand for occupational types and the accessibility to a post and monthly income; positive correlation…

  7. Computer Chips and Paper Clips. Technology and Women's Employment. Volume II. Case Studies and Policy Perspectives.

    ERIC Educational Resources Information Center

    Hartmann, Heidi I., Ed.; And Others

    This volume contains 12 papers commissioned by the Panel on Technology and Women's Employment. "Technology, Women, and Work: Policy Perspectives" (Eli Ginzberg) is an overview that provides a context for the volume. The four case studies in Part II describe the impact of information technology in the insurance industry, among bookkeepers, among…

  8. Higher Education and Employment: The Changing Relationship. Recent Developments in Continuing Professional Education. Country Study: Germany.

    ERIC Educational Resources Information Center

    Lullies, Stefan; Berning, Ewald

    This report, one of a series of country studies on higher education and employment particularly in continuing professional education, looks at recent developments in Germany. The first of six chapters offers a series of definitions of central concepts and focuses the paper's discussion on continuing education offered by higher education…

  9. A Decade of Study on Employer Feedback on the Quality of University Graduates

    ERIC Educational Resources Information Center

    Shah, Mahsood; Grebennikov, Leonid; Nair, Chenicheri Sid

    2015-01-01

    Purpose: The purpose of this paper is to outline four separate studies undertaken in two Australian universities between 2003 and 2012 on employer feedback on the quality of university graduates. Higher education has expanded significantly in the past decade. The expansion has been in student enrolments with a focus on increasing the participation…

  10. A STUDY OF EMPLOYMENT OPPORTUNITIES IN OFF-FARM AGRICULTURAL OCCUPATIONS IN ALABAMA.

    ERIC Educational Resources Information Center

    BAKER, RICHARD A.

    THE PURPOSE OF THE STUDY WAS TO ASCERTAIN THE NATURE AND EXTENT OF OFF-FARM AGRICULTURAL EMPLOYMENT OPPORTUNITIES IN THE STATE. BUSINESS FIRMS, OCCUPATIONS, OCCUPATIONAL CHARACTERISTICS, AND METHODS OF RECRUITMENT WERE IDENTIFIED. THE SAMPLES OF BUSINESS FIRMS WAS SELECTED FROM 20 SAMPLE COUNTIES. INTERVIEWERS CONTACTED 545 OF THE 638 FIRMS IN THE…

  11. International Students' Employment Search in the United States: A Phenomenological Study

    ERIC Educational Resources Information Center

    Sangganjanavanich, Varunee Faii; Lenz, A. Stephen; Cavazos, Javier, Jr.

    2011-01-01

    After completing their academic degree, international student populations face unique situations in their search for employment in the United States. This study used a phenomenological examination to identify the perceptions and the experiences of eight undergraduate international students who participated in a 10-week support group during the…

  12. Multisite Employment and Training Program Evaluations: A Tale of Three Studies.

    ERIC Educational Resources Information Center

    Greenberg, David; And Others

    1994-01-01

    Using a multilevel statistics framework, a study examined the role of multiple sites in evaluation of three programs: Greater Avenues to Independence (GAIN), Job Training Partnership Act, and Food Stamp Employment and Training. Although multisite evaluations have great potential, they are more difficult and expensive and have limited success in…

  13. Classifying University Employability Strategies: Three Case Studies and Implications for Practice and Research

    ERIC Educational Resources Information Center

    Farenga, Stéphane A.; Quinlan, Kathleen M.

    2016-01-01

    This qualitative study documents three main strategic models used by Russell Group Careers Services to support students' preparation for graduate careers. It is framed against the backdrop of a challenging graduate labour market, discussions of employability in the literature and the policy assumption that universities are responsible for…

  14. Employability Development in the Context of Doctoral Studies: Systemic Tensions and the Views of Key Stakeholders

    ERIC Educational Resources Information Center

    Golovushkina, Elena; Milligan, Colin

    2013-01-01

    Although the employability of doctoral candidates has been a topic of much discussion, the views of key institutional stakeholders on the subject are little understood. In order to address this gap, this study explores the perceptions of doctoral candidates, supervisors and researcher developers through semi-structured interviews. This small-scale…

  15. A STUDY OF RELATIONSHIPS BETWEEN THE EMPLOYMENT SERVICE ACTIVE FILE AND UNEMPLOYMENT, GREENSBORO - HIGH POINT AREA.

    ERIC Educational Resources Information Center

    North Carolina Employment Security Commission, Raleigh.

    THE PURPOSES OF THE STUDY WERE TO (1) EXAMINE THE RELATIONSHIP BETWEEN UNEMPLOYMENT AND THE ACTIVE FILE WHICH IS COMPOSED OF JOB APPLICATION FORMS LESS THAN 30 DAYS OLD, (2) DETERMINE THE EXTENT TO WHICH PERSONS HAVE REGISTERED IN MORE THAN ONE EMPLOYMENT SERVICE OFFICE IN AN AREA, (3) MEASURE THE EXTENT OF REGISTRATION BY PERSONS NOT LIVING IN…

  16. A study of education and KSAOs on career entry for product engineers: What employers really want

    NASA Astrophysics Data System (ADS)

    Thornburgh, James

    The purpose of the study was to investigate the ways that employers of product engineers evaluate potential employees' job readiness, and which theories related to the education-work transaction are supported by practice. This study used a mixed methods approach and consisted of a state-wide survey (N=106) and local interviews (N=8). The results of the research indicate that attributes of both the Theory of Individual Differences and Credentialing Theory are present in the hiring practices of product engineers. Consistent with the Theory of Individual Differences, employers indicate they look for evidence of various job-related Knowledge, Skills, Abilities, and Other attributes (KSAOs) and they indicate they are willing to hire applicants who have less than a bachelor's degree. Consistent with Credentialing Theory, employers advertise a formal education minimum which represents only one way that individuals may learn to be an engineer. This study also confirmed prior research that most employers use primarily non-evidence based predictors to evaluate applicants. The primary initial screening predictors were experience, GPA, and major, while the primary finalist selection predictors were unstructured interviews, and applications, followed by structured interviews, job knowledge tests, and work sample test. Contrary to previous findings, this study did not find any major differences between what HR professionals, engineering managers, or other manager look for in terms of qualifications or what predictors they use when evaluating applicants for product engineer positions.

  17. Exploratory Study of Relationships between Selected Aspects of Home Environment and Employment Criteria of the Husband.

    ERIC Educational Resources Information Center

    Souder, Mary Fern Vanpool

    The objectives of the study were to identify characteristics of home environment which appear to be related to employment history of the husband; test methods of obtaining information; and develop a rationale consistent with the findings and including hypotheses to be tested. Criteria for selecting a sample of 40 employees of a midwestern…

  18. Youth Employment, Crime, and Schooling: A Longitudinal Study of a National Sample.

    ERIC Educational Resources Information Center

    Gottfredson, Denise C.

    1985-01-01

    Data from a national study of delinquency prevention programs were used to examine the effect of teenage employment on delinquent behavior in preadolescents and adolescents. Models examined suggest working decreases school attendance and dependence on parents for some subgroups, but these effects are not translated into increases in delinquency.…

  19. Applicant Age as a Subjective Employability Factor: A Study of Workers over and under Age Fifty.

    ERIC Educational Resources Information Center

    Forte, Catherine Sabin; Hansvick, Christine L.

    1999-01-01

    Three hundred employers in a suburban area of the Pacific Northwest were surveyed for their perceptions of older (ages 50 and over) and younger (aged 49 and under) workers on 12 attributes. In contrast to previous research, this study found more favorable ratings for older workers overall, including categories such as attendance and salary…

  20. Longitudinal Study of Effects of Selected Employment and Training Services on Migrants and Other Seasonal Farmworkers.

    ERIC Educational Resources Information Center

    Berry, Dale

    1979-01-01

    Post-program labor force experiences of farmworkers receiving nonagricultural employment and training services from the CETA Title III farmworker program in 1975 were studied. Available from Farmworker Data Network, 7905 W. 44th, Wheat Ridge, Colorado 80033 ($12.00). (SB)

  1. The Perceived Value among Employers of College Study Abroad for Engineers

    ERIC Educational Resources Information Center

    Heiden, Christopher H.

    2012-01-01

    Engineering graduates of the twenty-first century must be worldly and understand how to work with professionals from many cultures on projects that cross international boundaries. Increasingly, employers are finding that prospective employees who have studied abroad make better, more rounded candidates than those who have no life experience…

  2. An Exploratory Study of the Impacts of an Employer-Supported Child Care Program

    ERIC Educational Resources Information Center

    Morrissey, Taryn W.; Warner, Mildred E.

    2011-01-01

    Although employer-sponsored child care programs have become more common, there is little empirical research on whether these programs affect employees' satisfaction with child care or their work-life balance, and if effects vary across employee characteristics. In this exploratory study, we administered a survey to employees with children at one…

  3. A Study of Teacher Employment Practices in Iowa, Kansas, Missouri and Nebraska.

    ERIC Educational Resources Information Center

    Lesher, Merle R.; Wade, Stanley

    This study provides the prospective teacher with information concerning the expectations of hiring officials and the practices and policies commonly used in the teacher employment process. A mail survey was sent to officials in 208 districts in Kansas, Missouri, Iowa, and Nebraska. The survey instrument consisted of a checklist and a section made…

  4. Self-Employment of Immigrants: A Cross-National Study of 17 Western Societies

    ERIC Educational Resources Information Center

    Tubergen, Frank van

    2005-01-01

    This study examines the role of immigrants' country of origin, country of destination and combinations thereof (settings or communities) in the likelihood of immigrants being self-employed. I pooled census data from three classic immigrant countries (Australia, Canada and the United States) and labor-force surveys from 14 countries in the European…

  5. Ordinary Lives: An Ethnographic Study of Young People Attending Entry to Employment Programmes

    ERIC Educational Resources Information Center

    Russell, Lisa; Simmons, Robin; Thompson, Ron

    2011-01-01

    This paper discusses the findings from a one-year ethnographic study of young people attending Entry to Employment (E2E) programmes in two local authorities in the north of England. The paper locates E2E within the broader context of provision for low-achieving young people and of UK government policy on reducing the proportion of young people who…

  6. The Perceived Value among Employers of College Study Abroad for Engineers

    ERIC Educational Resources Information Center

    Heiden, Christopher H.

    2012-01-01

    Engineering graduates of the twenty-first century must be worldly and understand how to work with professionals from many cultures on projects that cross international boundaries. Increasingly, employers are finding that prospective employees who have studied abroad make better, more rounded candidates than those who have no life experience…

  7. Changing Student Expectations and Graduate Employment: Case Studies from Xi'an, Shaanxi Province

    ERIC Educational Resources Information Center

    Moorman, Adam B. R.

    2011-01-01

    This paper addresses the issue of students' employment expectations, considered a key factor in alleviating graduate unemployment in China. This empirical investigation surveyed students at two higher education institutions in Xi'an, Shaanxi Province, to analyze how expectations were changing. The results contrasted with earlier studies that…

  8. German Dual Curricula to Improve School to Employment Transition: A Case Study

    ERIC Educational Resources Information Center

    Stephens, Maria Cecilia Noche

    2015-01-01

    The German Dual System is a model educational and employment approach that other nations could emulate. The ability of young apprentices to work and study at the same time to gain both practical and theoretical skills leads to more meaningful education and decreased dropout and youth unemployment rates. The collaboration of the government,…

  9. German Dual Curricula to Improve School to Employment Transition: A Case Study

    ERIC Educational Resources Information Center

    Stephens, Maria Cecilia Noche

    2015-01-01

    The German Dual System is a model educational and employment approach that other nations could emulate. The ability of young apprentices to work and study at the same time to gain both practical and theoretical skills leads to more meaningful education and decreased dropout and youth unemployment rates. The collaboration of the government,…

  10. A Decade of Study on Employer Feedback on the Quality of University Graduates

    ERIC Educational Resources Information Center

    Shah, Mahsood; Grebennikov, Leonid; Nair, Chenicheri Sid

    2015-01-01

    Purpose: The purpose of this paper is to outline four separate studies undertaken in two Australian universities between 2003 and 2012 on employer feedback on the quality of university graduates. Higher education has expanded significantly in the past decade. The expansion has been in student enrolments with a focus on increasing the participation…

  11. Classifying University Employability Strategies: Three Case Studies and Implications for Practice and Research

    ERIC Educational Resources Information Center

    Farenga, Stéphane A.; Quinlan, Kathleen M.

    2016-01-01

    This qualitative study documents three main strategic models used by Russell Group Careers Services to support students' preparation for graduate careers. It is framed against the backdrop of a challenging graduate labour market, discussions of employability in the literature and the policy assumption that universities are responsible for…

  12. Longitudinal Study of Effects of Selected Employment and Training Services on Migrants and Other Seasonal Farmworkers.

    ERIC Educational Resources Information Center

    Berry, Dale

    1979-01-01

    Post-program labor force experiences of farmworkers receiving nonagricultural employment and training services from the CETA Title III farmworker program in 1975 were studied. Available from Farmworker Data Network, 7905 W. 44th, Wheat Ridge, Colorado 80033 ($12.00). (SB)

  13. Self-Employment of Immigrants: A Cross-National Study of 17 Western Societies

    ERIC Educational Resources Information Center

    Tubergen, Frank van

    2005-01-01

    This study examines the role of immigrants' country of origin, country of destination and combinations thereof (settings or communities) in the likelihood of immigrants being self-employed. I pooled census data from three classic immigrant countries (Australia, Canada and the United States) and labor-force surveys from 14 countries in the European…

  14. Ordinary Lives: An Ethnographic Study of Young People Attending Entry to Employment Programmes

    ERIC Educational Resources Information Center

    Russell, Lisa; Simmons, Robin; Thompson, Ron

    2011-01-01

    This paper discusses the findings from a one-year ethnographic study of young people attending Entry to Employment (E2E) programmes in two local authorities in the north of England. The paper locates E2E within the broader context of provision for low-achieving young people and of UK government policy on reducing the proportion of young people who…

  15. The influence of crisis resolution treatment on employment: a retrospective register-based comparative study.

    PubMed

    Blæhr, Emely Ek; Madsen, Jacob Vagner; Christiansen, Nanna Limskov Stærk; Ankersen, Pia Vedel

    2017-08-24

    Crisis resolution treatment (CRT) is a short-term acute psychiatric home-based treatment offered as an alternative to hospitalization. The purpose of CRT is to support patient recovery by maintaining and improving competencies in relation to everyday life. Individuals with mental disorders are at increased risk of leaving the labor market, which is a central aspect of everyday life. Thus, a primary outcome of interest is whether CRT enables higher employment compared with traditional hospitalization. The aim of this study was to assess the effectiveness of CRT compared with hospitalization in relation to attempted or committed suicides, admissions, readmissions and employment. This study utilized register-based psychiatric data. The CRT intervention, which was carried out in a psychiatric center (N = 374), was matched to traditional hospitalization treatment in a corresponding area (N = 9460). The outcomes (suicide attempts, suicides, admissions and readmissions) were replicated by applying propensity score matching (PSM) to evaluate the general treatment effect of CRT. The effectiveness of CRT on employment was estimated by applying PSM combined with a difference-in-difference estimator to account for any time trends. Receiving CRT was associated with significantly more employment after 1 year compared with hospitalization. Furthermore, after 1 year, receiving CRT was associated with fewer suicide attempts, admissions and readmissions. The associations were not significant after two years. The results suggest that CRT patients retain a higher employment rate, which could indicate better recovery. Using CRT could lead to savings in the social security system owing to higher employment rates.

  16. An Employment Study of Miami-Dade Community College 1972-73 Career Education Students and Their Employers.

    ERIC Educational Resources Information Center

    Wenzel, Gustave G.; Corson, Hal

    This study was intended as a pilot project to design a method and computerized system for collecting, analyzing, and reporting information about the degree to which students in career occupational programs achieve their objective of attaining marketable skills. First, the 4,895 students enrolled in the 52 career education programs at Miami-Dade…

  17. Low-wage maternal employment and outcomes for children: a study.

    PubMed

    Moore, K A; Driscoll, A K

    1997-01-01

    Despite the importance of anticipating how children may be affected by policies that move mothers off welfare and into employment, as the article by Zaslow and Emig in this journal issue points out, few research studies have addressed this critical policy question. To help fill that gap, this article presents the results of a new study using national survey data to examine child outcomes among families that had previously received welfare. About half the families studied had mothers who remained at home, the others were working at varying wage levels. The findings reported here echo themes discussed in the two preceding articles. Maternal employment does not appear to undermine children's social or cognitive development from ages 5 to 14, and it may yield advantages. Children whose mothers earned more than $5.00 per hour, particularly, had somewhat better outcomes than others. The authors emphasize, however, that background characteristics specific to the mothers who chose employment contributed to these positive outcomes. The authors add that it would be risky to apply these generalizations based on these findings to families forced into employment by welfare reform.

  18. A Study of the Federal Communications Commission's Equal Employment Opportunity Regulation--An Agency in Search of a Standard.

    ERIC Educational Resources Information Center

    Bowie, Nolan A.; Whitehead, John W.

    This study examines the performance of the Federal Courts and the Federal Communications Commission (FCC) in monitoring the efforts of broadcasters to guarantee equal employment opportunity, focusing on the use of employment statistics as an indication of effective equal-employment practices. Sections of the study include: court decisions…

  19. A Study of the Federal Communications Commission's Equal Employment Opportunity Regulation--An Agency in Search of a Standard.

    ERIC Educational Resources Information Center

    Bowie, Nolan A.; Whitehead, John W.

    This study examines the performance of the Federal Courts and the Federal Communications Commission (FCC) in monitoring the efforts of broadcasters to guarantee equal employment opportunity, focusing on the use of employment statistics as an indication of effective equal-employment practices. Sections of the study include: court decisions…

  20. The impact of maternal employment on breast-feeding duration in the UK Millennium Cohort Study.

    PubMed

    Hawkins, Summer Sherburne; Griffiths, Lucy Jane; Dezateux, Carol; Law, Catherine

    2007-09-01

    To examine the relationship of maternal employment characteristics, day care arrangements and the type of maternity leave pay to breast-feeding for at least 4 months. Cohort study. Babies aged 9 months in the Millennium Cohort Study, born between September 2000 and January 2002. A total of 6917 British/Irish white employed mothers with singleton babies. Mothers employed part-time or self-employed were more likely to breast-feed for at least 4 months than those employed full-time (adjusted rate ratio (aRR) and 95% confidence interval (CI) 1.30 (1.17-1.44) and 1.74 (1.46-2.07), respectively). The longer a mother delayed her return to work postpartum, the more likely she was to breast-feed for at least 4 months (P for trend < 0.001). Mothers were less likely to breast-feed for at least 4 months if they returned to work for financial reasons (aRR 0.86, 95% CI 0.80-0.93) or used informal day care arrangements rather than care by themselves or their partner (aRR 0.81, 95% CI 0.71-0.91). Mothers were more likely to breastfeed for at least 4 months if their employer offered family-friendly (aRR 1.14, 95% CI 1.02-1.27) or flexible work arrangements (aRR 1.24, 95% CI 1.00-1.55), or they received Statutory Maternity Pay (SMP) plus additional pay during their maternity leave rather than SMP alone (aRR 1.13, 95% CI 1.02-1.26). These findings were independent of confounding factors, such as socio-economic status and maternal education. Current policies may encourage mothers to enter or return to employment postpartum, but this may result in widening inequalities in breast-feeding and persistence of low rates. Policies should aim to increase financial support and incentives for employers to offer supportive work arrangements.

  1. Dollars and Sense: Employer-Supported Child Care. A Study on Child Care Needs, and the Realities of Employer-Support.

    ERIC Educational Resources Information Center

    Douglas, Jane I., Ed.

    This report briefly discusses present rationales, future prospects, and methods and procedures involved in employer support of child care. It is based on a study which was intended to test the feasibility of providing child care and youth programs, through a system design, for employees of resort hotels and the primary labor union involved with…

  2. Employer-based support for registered nurses undertaking postgraduate study via distance education.

    PubMed

    Black, Kirsten E; Bonner, Ann

    2011-02-01

    Previous literature has focused on the need for support of undergraduate nursing students during clinical placements. Little is known about the support provided by employers for registered nurses (RNs) who pursue further education. This study sought to identify and describe the types, levels and perceived need for support in the workplace for RNs as they undertake further postgraduate nursing study by distance education (DE). Using an exploratory descriptive design a self-report questionnaire was distributed to a convenient sample of 270 RNs working in one acute care public hospital in Tasmania, Australia. 92 questionnaires (response rate 34%) were returned with 26 (28%) reporting being currently enrolled in further study by DE and a further 50 (54)% of RNs planning future study. Results revealed that 100% of participants with a Masters degree completed this by DE. There were differences between the support sought by RNs to that offered by employers, and 16 (34%) who had done or were currently doing DE study, received no support to undertake DE. There was an overwhelming desire by RNs for support; 87 (94%), with a majority believing some support should be mandatory 76 (83%). This study may encourage employers to introduce structured support systems that will actively assist nurses to pursue further study.

  3. Oxidoreductases on their way to industrial biotransformations.

    PubMed

    Martínez, Angel T; Ruiz-Dueñas, Francisco J; Camarero, Susana; Serrano, Ana; Linde, Dolores; Lund, Henrik; Vind, Jesper; Tovborg, Morten; Herold-Majumdar, Owik M; Hofrichter, Martin; Liers, Christiane; Ullrich, René; Scheibner, Katrin; Sannia, Giovanni; Piscitelli, Alessandra; Pezzella, Cinzia; Sener, Mehmet E; Kılıç, Sibel; van Berkel, Willem J H; Guallar, Victor; Lucas, Maria Fátima; Zuhse, Ralf; Ludwig, Roland; Hollmann, Frank; Fernández-Fueyo, Elena; Record, Eric; Faulds, Craig B; Tortajada, Marta; Winckelmann, Ib; Rasmussen, Jo-Anne; Gelo-Pujic, Mirjana; Gutiérrez, Ana; Del Río, José C; Rencoret, Jorge; Alcalde, Miguel

    2017-11-01

    transfer efficiency in biochemical simulations, reducing in orders of magnitude the time of experimental work in oxidoreductase screening and engineering. What has been set out above is illustrated by a series of remarkable oxyfunctionalization and oxidation reactions developed in the frame of an intersectorial and multidisciplinary European RTD project. The optimized reactions include enzymatic synthesis of 1-naphthol, 25-hydroxyvitamin D3, drug metabolites, furandicarboxylic acid, indigo and other dyes, and conductive polyaniline, terminal oxygenation of alkanes, biomass delignification and lignin oxidation, among others. These successful case stories demonstrate the unexploited potential of oxidoreductases in medium and large-scale biotransformations. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  4. ‘Placement budgets’ for supported employment – improving competitive employment for people with mental illness: study protocol of a multicentre randomized controlled trial

    PubMed Central

    2012-01-01

    Background Vocational integration of people with mental illness is poor despite their willingness to work. The ‘Individual Placement and Support’ (IPS) model which emphasises rapid and direct job placement and continuing support to patient and employer has proven to be the most effective vocational intervention programme. Various studies have shown that every second patient with severe mental illness was able to find competitive employment within 18 months. However, the goal of taking up employment within two months was rarely achieved. Thus, we aim to test whether the new concept of limited placement budgets increases the effectiveness of IPS. Methods/Design Six job coaches in six out-patients psychiatric clinics in the Canton of Zurich support unemployed patients of their clinic who seek competitive employment. Between June 2010 and May 2011 patients (N=100) are randomly assigned to three different placement budgets of 25h, 40h, or 55h working hours of job coaches. Support lasts two years for those who find a job. The intervention ends for those who fail to find competitive employment when the respective placement budgets run out. The primary outcome measure is the time between study inclusion and first competitive employment that lasted three months or longer. Over a period of three years interviews are carried out every six months to measure changes in motivation, stigmatization, social network and social support, quality of life, job satisfaction, financial situation, and health conditions. Cognitive and social-cognitive tests are conducted at baseline to control for confounding variables. Discussion This study will show whether the effectiveness of IPS can be increased by the new concept of limited placement budgets. It will also be examined whether competitive employment leads in the long term to an improvement of mental illness, to a transfer of the psychiatric support system to private and vocational networks, to an increase in financial independence

  5. 'Placement budgets' for supported employment--improving competitive employment for people with mental illness: study protocol of a multicentre randomized controlled trial.

    PubMed

    Nordt, Carlos; Brantschen, Elisabeth; Kawohl, Wolfram; Bärtsch, Bettina; Haker, Helene; Rüsch, Nicolas; Rössler, Wulf

    2012-10-04

    Vocational integration of people with mental illness is poor despite their willingness to work. The 'Individual Placement and Support' (IPS) model which emphasises rapid and direct job placement and continuing support to patient and employer has proven to be the most effective vocational intervention programme. Various studies have shown that every second patient with severe mental illness was able to find competitive employment within 18 months. However, the goal of taking up employment within two months was rarely achieved. Thus, we aim to test whether the new concept of limited placement budgets increases the effectiveness of IPS. Six job coaches in six out-patients psychiatric clinics in the Canton of Zurich support unemployed patients of their clinic who seek competitive employment. Between June 2010 and May 2011 patients (N=100) are randomly assigned to three different placement budgets of 25h, 40h, or 55h working hours of job coaches. Support lasts two years for those who find a job. The intervention ends for those who fail to find competitive employment when the respective placement budgets run out. The primary outcome measure is the time between study inclusion and first competitive employment that lasted three months or longer. Over a period of three years interviews are carried out every six months to measure changes in motivation, stigmatization, social network and social support, quality of life, job satisfaction, financial situation, and health conditions. Cognitive and social-cognitive tests are conducted at baseline to control for confounding variables. This study will show whether the effectiveness of IPS can be increased by the new concept of limited placement budgets. It will also be examined whether competitive employment leads in the long term to an improvement of mental illness, to a transfer of the psychiatric support system to private and vocational networks, to an increase in financial independence, to a reduction of perceived and

  6. Arsenic biotransformation in solid waste residue: comparison of contributions from bacteria with arsenate and iron reducing pathways.

    PubMed

    Tian, Haixia; Shi, Qiantao; Jing, Chuanyong

    2015-02-17

    Arsenic- and iron-reducing bacteria play an important role in regulating As redox transformation and mobility. The motivation of this study was to compare the contributions of different As- and Fe-reducing bacteria to As biotransformation. In this work, three bacteria strains with different functional genes were employed including Pantoea sp. IMH with the arsC gene, Alkaliphilus oremlandii OhILAs possessing the arrA gene, and Shewanella oneidensis MR-1, an iron reducer. The incubation results showed that Pantoea sp. IMH aerobically reduced 100% of As(V) released from waste residues, though total As release was not enhanced. Similarly, strain OhILAs anaerobically reduced dissolved As(V) but could not enhance As release. In contrast, strain MR-1 substantially enhanced As mobilization because of iron reduction, but without changing the As speciation. The formation of the secondary iron mineral pyrite in the MR-1 incubation experiments, as evidenced by the X-ray absorption near-edge spectroscopy (XANES) analysis, contributed little to the uptake of the freed As. Our results suggest that the arsC gene carriers mainly control the As speciation in the aqueous phase in aerobic environments, whereas in anaerobic conditions, the As speciation should be regulated by arrA gene carriers, and As mobility is greatly enhanced by iron reduction.

  7. The Impact of Different Proportions of a Treated Effluent on the Biotransformation of Selected Micro-Contaminants in River Water Microcosms

    PubMed Central

    Nödler, Karsten; Tsakiri, Maria; Licha, Tobias

    2014-01-01

    Attenuation of micro-contaminants is a very complex field in environmental science and evidence suggests that biodegradation rates of micro-contaminants in the aqueous environment depend on the water matrix. The focus of the study presented here is the systematic comparison of biotransformation rates of caffeine, carbamazepine, metoprolol, paracetamol and valsartan in river water microcosms spiked with different proportions of treated effluent (0%, 0.1%, 1%, and 10%). Biotransformation was identified as the dominating attenuation process by the evolution of biotransformation products such as atenolol acid and valsartan acid. Significantly decreasing biotransformation rates of metoprolol were observed at treated effluent proportions ≥0.1% whereas significantly increasing biotransformation rates of caffeine and valsartan were observed in the presence of 10% treated effluent. Potential reasons for the observations are discussed and the addition of adapted microorganisms via the treated effluent was suggested as the most probable reason. The impact of additional phosphorus on the biodegradation rates was tested and the experiments revealed that phosphorus-limitation was not responsible. PMID:25310538

  8. The impact of different proportions of a treated effluent on the biotransformation of selected micro-contaminants in river water microcosms.

    PubMed

    Nödler, Karsten; Tsakiri, Maria; Licha, Tobias

    2014-10-10

    Attenuation of micro-contaminants is a very complex field in environmental science and evidence suggests that biodegradation rates of micro-contaminants in the aqueous environment depend on the water matrix. The focus of the study presented here is the systematic comparison of biotransformation rates of caffeine, carbamazepine, metoprolol, paracetamol and valsartan in river water microcosms spiked with different proportions of treated effluent (0%, 0.1%, 1%, and 10%). Biotransformation was identified as the dominating attenuation process by the evolution of biotransformation products such as atenolol acid and valsartan acid. Significantly decreasing biotransformation rates of metoprolol were observed at treated effluent proportions ≥ 0.1% whereas significantly increasing biotransformation rates of caffeine and valsartan were observed in the presence of 10% treated effluent. Potential reasons for the observations are discussed and the addition of adapted microorganisms via the treated effluent was suggested as the most probable reason. The impact of additional phosphorus on the biodegradation rates was tested and the experiments revealed that phosphorus-limitation was not responsible.

  9. Equality of employment opportunities for nurses at the point of qualification: an exploratory study.

    PubMed

    Harris, Ruth; Ooms, Ann; Grant, Robert; Marshall-Lucette, Sylvie; Chu, Christine Sek Fun; Sayer, Jane; Burke, Linda

    2013-03-01

    Securing employment after qualification is of utmost importance to newly qualified nurses to consolidate knowledge and skills. The factors that influence success in gaining this first post are not known. The study aimed to describe the first post gained after qualification in terms of setting, nature of employment contract and geographical distribution and explore the relationship between a range of factors (including ethnicity) and employment at the point of qualification. An exploratory study using structured questionnaires and secondary analysis of data routinely collected by the universities about students and their progress during their course. The study was conducted in eight universities within a large, multicultural city in the UK as part of the 'Readiness for Work' research programme. Eight hundred and four newly qualified nurses who had successfully completed a diploma or degree from one of the universities; a response rate of 77% representing 49% of all graduating students in the study population. Data were collected by self-completed semi-structured questionnaires administered to students at the time of qualification and at three months post-qualification. Routinely collected data from the universities were also collected. Fifty two percent of participants had been offered a job at the point of qualification (85% of those who had applied and been interviewed). Of these, 99% had been offered a nursing post, 88% in the city studied, 67% in the healthcare setting where they had completed a course placement. 44% felt "confident" and 32% "very confident" about their employment prospects. Predictors of employment success included ethnicity, specialty of nursing and university attended. Predictors of confidence and preparedness for job seeking included ethnicity, nursing specialty, gender and grade of degree. Newly qualified nurses from non-White/British ethnic groups were less likely to get a job and feel confident about and prepared for job seeking. This

  10. Toxicity, Bioaccumulation and Biotransformation of Silver Nanoparticles in Marine Organisms

    EPA Science Inventory

    The toxicity, bioaccumulation and biotransformation of citrate and polyvinylpyrrolidone (PVP) capped silver nanoparticles (NPs) (AgNP-citrate and AgNP-PVP) and titanium dioxide (TiO2) NPs in marine organisms via marine sediment exposure were investigated. Results from 7-d sedimen...

  11. Effects of Food Natural Products on the Biotransformation of PCBs

    PubMed Central

    James, Margaret O.; Sacco, James C.; Faux, Laura R

    2008-01-01

    Many food products, particularly fruits and vegetables, contain natural products that affect biotransformation enzymes. These may be expected to affect the rate of biotransformation of PCBs that are metabolized by the affected enzymes. The first step in PCB metabolism is cytochrome P450-dependent monooxygenation. Natural products present in cruciferous vegetables have been shown to selectively up-regulate CYP1A1 and CYP1A2 isozymes on chronic ingestion, and may lead to increased metabolism of those PCB congeners that are substrates for the induced P450s. On the other hand, several natural products selectively inhibit monooxygenation, especially in the intestine, and may lead to increased bioavailability and reduced metabolism of dietary PCBs. Food natural products are known to affect phase II pathways important in the detoxication of hydroxylated PCBs, namely UDP-glucuronosyltransferase and PAPS-sulfotransferase. Continual dietary exposure to chrysin and quercetin, found in fruits and vegetables, induces UGT1A1 and may reduce exposure to hydroxylated PCBs through increased glucuronidation. These and other natural products are also inhibitors of glucuronidation and sulfonation, potentially leading to transient decreases in the elimination of hydroxylated PCBs. In summary, the expected effects of food natural products on PCB biotransformation are complex and may be biphasic, with initial inhibition followed by enhanced biotransformation through monooxygenation and conjugation pathways. PMID:19255595

  12. Physiologically based modeling of hepatic and gastrointestinal biotransformation in fish

    EPA Science Inventory

    In fish, as in mammals, the liver generally viewed as the principal site of chemical biotransformation. For waterborne exposures, such as those conducted in support of standardized BCF testing, the effects of hepatic metabolism on chemical accumulation can be simulated using rela...

  13. Physiologically based modeling of hepatic and gastrointestinal biotransformation in fish

    EPA Science Inventory

    In fish, as in mammals, the liver generally viewed as the principal site of chemical biotransformation. For waterborne exposures, such as those conducted in support of standardized BCF testing, the effects of hepatic metabolism on chemical accumulation can be simulated using rela...

  14. Biotransformation of furanocoumarins by fungi: preparation of imperation analogs.

    PubMed

    Xin, Xiu-Lan; Wang, Yan; Wang, Ge; Wang, Chao; Huang, Shan-Shan; Huo, Xiao-Kui; Su, Dong-Hai; Tian, Xiang-Ge

    2017-01-31

    Imperation analogs have the furanocoumarin skeleton, with the isopentenyl group, which displayed significant bioactivities. The biotransformation of furanocoumarins imperation, isoimperation and phellopterin (1-3) by fungi has been proved to be an efficient method for the structural modification. Ten transformed furanocoumarin analogs were obtained by fungal biotransformation, including one new highly oxygenated furanocoumarin (4c). Aspergillus niger AS 3.739 displayed selectively transformed capability toward furanocouamrins (1-3) with one or two major products. So, seven hydroxylation and hydrolysis derivatives have been prepared efficiently. Additionally, the biotransformation of phellopterin gave multiple products (4a, 4b, 4c) by Cunninghamella blakesleana AS 3.970. The biotransformation time-courses of furanocoumarins have been established, which suggested the preferred incubation time. The bioactivities of furanocoumarin analogs have been investigated in an in vitro bioassay. And, furanocoumarins 1-3, 2a, and 2c displayed moderate anti-osteoporosis activities using MCET3-E1 cell line at the concentrations of 1, 10, and 100 μM.

  15. Biotransformation of the fungistatic sesquiterpenoid patchoulol by botrytis cinerea

    PubMed

    Aleu; Hanson; Galan; Collado

    1999-03-01

    Biotransformation of the fungistatic sesquiterpenoid patchoulol (1) by the fungus Botrytis cinerea affords the 5-, 7- and (8R)-hydroxy (2, 3, and 5) derivatives as the major metabolites, together with a number of minor metabolites (4, 6-9) arising from hydroxylation at C-2, C-3, C-5, C-9, C-13, and C-14.

  16. Toxicity, Bioaccumulation and Biotransformation of Silver Nanoparticles in Marine Organisms.

    EPA Science Inventory

    The toxicity, bioaccumulation and biotransformation of citrate and polyvinylpyrrolidone (PVP) coated silver nanoparticles (NPs) (AgNP-citrate and AgNP-PVP) in marine organisms via marine sediment exposure was investigated. Results from 7-d sediment toxicity tests indicate that Ag...

  17. Toxicity, Bioaccumulation and Biotransformation of Silver Nanoparticles in Marine Organisms.

    EPA Science Inventory

    The toxicity, bioaccumulation and biotransformation of citrate and polyvinylpyrrolidone (PVP) coated silver nanoparticles (NPs) (AgNP-citrate and AgNP-PVP) in marine organisms via marine sediment exposure was investigated. Results from 7-d sediment toxicity tests indicate that Ag...

  18. Toxicity, Bioaccumulation and Biotransformation of Silver Nanoparticles in Marine Organisms

    EPA Science Inventory

    The toxicity, bioaccumulation and biotransformation of citrate and polyvinylpyrrolidone (PVP) capped silver nanoparticles (NPs) (AgNP-citrate and AgNP-PVP) and titanium dioxide (TiO2) NPs in marine organisms via marine sediment exposure were investigated. Results from 7-d sedimen...

  19. Effects of Food Natural Products on the Biotransformation of PCBs.

    PubMed

    James, Margaret O; Sacco, James C; Faux, Laura R

    2008-03-01

    Many food products, particularly fruits and vegetables, contain natural products that affect biotransformation enzymes. These may be expected to affect the rate of biotransformation of PCBs that are metabolized by the affected enzymes. The first step in PCB metabolism is cytochrome P450-dependent monooxygenation. Natural products present in cruciferous vegetables have been shown to selectively up-regulate CYP1A1 and CYP1A2 isozymes on chronic ingestion, and may lead to increased metabolism of those PCB congeners that are substrates for the induced P450s. On the other hand, several natural products selectively inhibit monooxygenation, especially in the intestine, and may lead to increased bioavailability and reduced metabolism of dietary PCBs. Food natural products are known to affect phase II pathways important in the detoxication of hydroxylated PCBs, namely UDP-glucuronosyltransferase and PAPS-sulfotransferase. Continual dietary exposure to chrysin and quercetin, found in fruits and vegetables, induces UGT1A1 and may reduce exposure to hydroxylated PCBs through increased glucuronidation. These and other natural products are also inhibitors of glucuronidation and sulfonation, potentially leading to transient decreases in the elimination of hydroxylated PCBs. In summary, the expected effects of food natural products on PCB biotransformation are complex and may be biphasic, with initial inhibition followed by enhanced biotransformation through monooxygenation and conjugation pathways.

  20. The Employability of Older Workers as Teleworkers: An Appraisal of Issues and an Empirical Study

    PubMed Central

    Sharit, Joseph; Czaja, Sara J.; Hernandez, Mario A.; Nair, Sankaran N.

    2009-01-01

    The aging of the population and, concomitantly, of the workforce has a number of important implications for governments, businesses, and workers. In this article, we examine the prospects for the employability of older workers as home-based teleworkers. This alternative work could accommodate many of the needs and preferences of older workers and at the same time benefit organizations. However, before telework can be considered a viable work option for many older workers there are a number of issues to consider, including the ability of older workers to adapt to the technological demands that are typically associated with telework jobs and managerial attitudes about older workers and about telework. Through an integrated examination of these and other issues, our goal is to provide a comprehensive understanding of the challenges associated with employing older workers as teleworkers. We also present findings from a questionnaire study that assessed managers’ perceptions of worker attributes desirable for telework and how older workers compare to younger workers on these attributes. The sample included 314 managers with varying degrees of managerial experience from a large variety of companies in the United States. The results presented a mixed picture with respect to the employability of older workers as teleworkers, and strongly suggested that less experienced managers would be more resistant to hiring older people as teleworkers. We conclude with a number of recommendations for improving the prospects for employment of older workers for this type of work arrangement. PMID:20090856

  1. The Employability of Older Workers as Teleworkers: An Appraisal of Issues and an Empirical Study.

    PubMed

    Sharit, Joseph; Czaja, Sara J; Hernandez, Mario A; Nair, Sankaran N

    2009-01-01

    The aging of the population and, concomitantly, of the workforce has a number of important implications for governments, businesses, and workers. In this article, we examine the prospects for the employability of older workers as home-based teleworkers. This alternative work could accommodate many of the needs and preferences of older workers and at the same time benefit organizations. However, before telework can be considered a viable work option for many older workers there are a number of issues to consider, including the ability of older workers to adapt to the technological demands that are typically associated with telework jobs and managerial attitudes about older workers and about telework. Through an integrated examination of these and other issues, our goal is to provide a comprehensive understanding of the challenges associated with employing older workers as teleworkers. We also present findings from a questionnaire study that assessed managers' perceptions of worker attributes desirable for telework and how older workers compare to younger workers on these attributes. The sample included 314 managers with varying degrees of managerial experience from a large variety of companies in the United States. The results presented a mixed picture with respect to the employability of older workers as teleworkers, and strongly suggested that less experienced managers would be more resistant to hiring older people as teleworkers. We conclude with a number of recommendations for improving the prospects for employment of older workers for this type of work arrangement.

  2. An empirical study of employment and disability over three years among survivors of major disasters.

    PubMed

    Rasco, Sarah S; North, Carol S

    2010-01-01

    This study was designed to clarify the relationship between exposure to disaster and future employment. Survivors of seven disasters and their employment histories were prospectively followed over three years. At the time of the disasters, 86 percent were working, and at follow-up, 84 percent were working. All of the 261 individuals employed on the day of the disaster described themselves as not disabled at follow-up, although one individual who dropped out of the workforce to become a self-described housewife shortly after the disaster and who developed PTSD may have left the workforce because of lasting emotional effects of the disaster. The reasons she provided for changing job status were not disaster related, however. Long-standing employment disability was virtually nonexistent in this highly exposed sample of trauma survivors, but it is possible that some cases of PTSD-related disability were lost to follow-up. Further work is needed to explore psychological disability in other trauma survivor populations.

  3. The Employer Potential of MOOCs: A Mixed-Methods Study of Human Resource Professionals' Thinking on MOOCs

    ERIC Educational Resources Information Center

    Radford, Alexandria Walton; Robles, Jessica; Cataylo, Stacey; Horn, Laura; Thornton, Jessica; Whitfield, Keith E.

    2014-01-01

    While press coverage of MOOCs (massive open online courses) has been considerable and major MOOC providers are beginning to realize that employers may be a market for their courses, research on employers' receptivity to using MOOCs is scarce. To help fill this gap, the Finding and Developing Talent study surveyed 103 employers and interviewed a…

  4. Classics in the Market Place: An Independent Research Study on Attitudes to the Employment of Classics Graduates.

    ERIC Educational Resources Information Center

    Council of Univ. Classical Departments.

    This study examined employers' attitudes to recruiting Classics graduates with the primary aim of determining employers' criteria when recruiting graduates and of assessing how far Classics graduates matched these criteria. Sixteen employers of Classics graduates from a cross-section of blue-chip organizations in industry, commerce and the public…

  5. A Study of Activities of Daily Living and Employment in Adults with Autism Spectrum Disorders in Taiwan

    ERIC Educational Resources Information Center

    Lin, Ling-Yi; Yu, Shu-Ning; Yu, Ya-Tsu

    2012-01-01

    Research on daily living activities and employment levels of adults with autism spectrum disorders (ASD) in Taiwan is limited. The aims of the study were to investigate outcomes related to functional independence and employment among people with ASD in Taiwan. We investigated the daily living activities and the employment status of 81 adults (age…

  6. A Study of Activities of Daily Living and Employment in Adults with Autism Spectrum Disorders in Taiwan

    ERIC Educational Resources Information Center

    Lin, Ling-Yi; Yu, Shu-Ning; Yu, Ya-Tsu

    2012-01-01

    Research on daily living activities and employment levels of adults with autism spectrum disorders (ASD) in Taiwan is limited. The aims of the study were to investigate outcomes related to functional independence and employment among people with ASD in Taiwan. We investigated the daily living activities and the employment status of 81 adults (age…

  7. A Descriptive Study of Occupational Health Services in Self-employed Enterprises (Nanoscale Enterprises), Shiraz, Iran.

    PubMed

    Jahangiri, Mehdi; Rostamabadi, Akbar; Yekzamani, Parvaneh; Mahmood Abadi, Bahare; Behbood, Fariborz; Ahmadi, Seyyedeh Fatemeh; Momeni, Zahra

    2016-12-01

    This study was conducted with aim of providing an overview of the current status of occupational health services and identifying the most common harmful agents at workplaces of Iranian self-employed enterprises (Nano-Scale Enterprises). A cross-sectional study was performed among a random sample including 1,758 employees engaging in self-employed enterprises with 5 and less employees. Coverage of occupational health surveillance was very poor, annual health examinations were been conducted only for 64 (3.64%) of males and 31 (1.76%) of females, and occupational health trainings were not included of the services at all. Personal Protective Equipment were available in 462 (26.3%) of the enterprises. only in 0.4% of the enterprises working processes were been equipped by a local exhaust ventilation system. Difficult postures were the most common (81.5%) adverse working conditions. This study revealed a poor level of the implementation of occupational health services in Iranian self-employed enterprises. Based on the findings, providing basic training on the occupational health, more enforcing in conduction of health examinations and providing PPE, and taking appropriate strategies aimed at eliminating or minimizing work environment harmful agents are the major factor that should be considered to improve the level of occupational health services among the studied enterprises.

  8. A mortality study of workers employed in a German rock wool factory.

    PubMed

    Claude, J; Frentzel-Beyme, R

    1984-06-01

    As part of a coordinated European study including 13 plants, 2,096 workers employed in rock wool production, packing, and maintenance activities in a German factory were followed until 1979 for cause-specific mortality. There were no consistent differences between the observed and expected deaths in the study cohort on the basis of the experience of the general population. The separate analysis of persons engaged in rock wool production and packing and those engaged in maintenance yielded an excess of lung cancer deaths with borderline significance for occurrence among the maintenance workers and an elevation in standardized mortality ratio for stomach cancer related to time since first employment in the production group. Comparison with a factory-based reference cohort did not show any increased health risk for the exposed cohort. An extension of the follow-up for five years is planned in an attempt to clarify the present findings.

  9. Physical, Mental and Neurocognitive Status and Employment Outcomes in the Childhood Cancer Survivor Study Cohort

    PubMed Central

    Kirchhoff, Anne C.; Krull, Kevin R.; Ness, Kirsten K.; Armstrong, Gregory T.; Park, Elyse R.; Stovall, Marilyn; Robison, Leslie L.; Leisenring, Wendy

    2011-01-01

    Introduction We examined the relationship of physical, mental, and neurocognitive function with employment and occupational status in the Childhood Cancer Survivor Study. Methods We included survivors ≥25 years of age with available Short Form-36 (physical and mental health component scores), Brief Symptom Inventory (depression, anxiety and somatization), and Neurocognitive Questionnaire (task efficiency, emotional regulation, organization, and memory). We generated relative risks (RR) from generalized linear models for these measures on unemployment (N=5386) and occupation (N=3763) outcomes adjusted for demographic and cancer-related factors, and generated sex-stratified models. Results Poor physical health was associated with an almost 8-fold higher risk of health-related unemployment (p<0.001) compared to survivors with normal physical health. Male survivors with somatization and memory problems were approximately 50% (p<0.05 for both) more likely to report this outcome, while task efficiency limitations was significant for both sexes (males: RR=2.43, p<0.001; females: RR=2.28, p<0.001). Employed female survivors with task efficiency, emotional regulation, and memory limitations were 13%-20% (p<0.05 for all) less likely to work in professional or managerial occupations than unaffected females. Conclusions Physical problems may cause much of the health-related unemployment among childhood cancer survivors. While both male and female survivors with neurocognitive deficits – primarily in task efficiencies – are at risk for unemployment, employed female survivors with neurocognitive deficits may face poor occupational outcomes more often than males. Impact Childhood cancer survivors are at risk for poor employment outcomes. Screening and intervention for physical, mental and neurocognitive limitations could improve employment outcomes for this population. PMID:21844244

  10. Physical, mental, and neurocognitive status and employment outcomes in the childhood cancer survivor study cohort.

    PubMed

    Kirchhoff, Anne C; Krull, Kevin R; Ness, Kirsten K; Armstrong, Gregory T; Park, Elyse R; Stovall, Marilyn; Robison, Leslie L; Leisenring, Wendy

    2011-09-01

    We examined the relationship of physical, mental, and neurocognitive function with employment and occupational status in the Childhood Cancer Survivor Study. We included survivors 25 years or older with available short form-36 (physical and mental health component scores), brief symptom inventory (depression, anxiety, and somatization), and neurocognitive questionnaire (task efficiency, emotional regulation, organization, and memory). We generated relative risks (RR) from generalized linear models for these measures on unemployment (n = 5,386) and occupation (n = 3,763) outcomes adjusted for demographic and cancer-related factors and generated sex-stratified models. Poor physical health was associated with an almost eightfold higher risk of health-related unemployment (P < 0.001) compared to survivors with normal physical health. Male survivors with somatization and memory problems were approximately 50% (P < 0.05 for both) more likely to report this outcome, whereas task efficiency limitations were significant for both sexes (males: RR = 2.43, P < 0.001; females: RR = 2.28, P < 0.001). Employed female survivors with task efficiency, emotional regulation, and memory limitations were 13% to 20% (P < 0.05 for all) less likely to work in professional or managerial occupations than unaffected females. Physical problems may cause much of the health-related unemployment among childhood cancer survivors. Whereas both male and female survivors with neurocognitive deficits--primarily in task efficiencies--are at risk for unemployment, employed female survivors with neurocognitive deficits may face poor occupational outcomes more often than males. Childhood cancer survivors are at risk for poor employment outcomes. Screening and intervention for physical, mental, and neurocognitive limitations could improve employment outcomes for this population.

  11. Catastrophic health expenditure according to employment status in South Korea: a population-based panel study

    PubMed Central

    Choi, Jae Woo; Kim, Tae Hyun; Jang, Sung In; Jang, Suk Yong; Kim, Woo-Rim; Park, Eun Cheol

    2016-01-01

    Objectives Catastrophic health expenditure (CHE) means that the medical spending of a household exceeds a certain level of capacity to pay. Previous studies of CHE have focused on benefits supported by the public sector or high medical cost incurred by treating diseases in South Korea. This study examines variance of CHE in these households according to changes in employment status. We also determine whether a relationship exists according to income level. Design A longitudinal study. Setting We used the Korean Welfare Panel Study (KOWEPS) conducted by the Korea Institute. Participants The data came from 5335 households during 2009–2012. Outcome measure CHE, defined as health expenditures that were 40% greater than the ability of the household to pay. Results Households with people who experienced changes in job status from employed to unemployed (OR 2.79, 95% CI 2.06 to 3.78) or were unemployed with no status change (OR 1.57, 95% CI 1.28 to 1.92) were more likely to incur CHE than those containing people who were consistently employed. In addition, low-income families with members who had either lost a job (OR 3.52, 95% CI 2.44 to 5.10) or were already unemployed (OR 1.67, 95% CI 1.29 to 2.16) were more likely to incur CHE than those with family members with a consistent job. Conclusions Given the insecure employment status of people with low income, they are more likely to face barriers in obtaining needed health services. Meeting their healthcare needs is an important consideration. PMID:27456329

  12. Biotransformation of phosphogypsum in media containing different forms of nitrogen.

    PubMed

    Rzeczycka, M; Mycielski, R; Kowalski, W; Gałazka, M

    2001-01-01

    Studies on the biotransformation of phosphogypsum (a waste product formed in the course of the production of phosphorous fertilizers) with the use of sulfate reducing bacteria (SRB) demonstrated that it is a good source of sulfates and biogenic elements for these bacteria, though the addition of organic carbon and nitrogen is necessary. The aim of this study was to investigate the form of nitrogen and C:N ratio in the medium on the growth of SRB community in cultures containing phosphogypsum. Batch community cultures of sulfate reducing bacteria were maintained in medium with phosphogypsum (5.0 g/l), different concentrations of sodium lactate (1.6 - 9.4 g/l) and different forms (NH4CI, CO(NH2)2, KNO3) and concentrations (0 - 250 mg/l) of nitrogen. The growth of SRB was studied in the C:N ratio of from 2:1 to 300:1. It was found that: 1 - the best source of nitrogen for SRB is urea, followed by ammonium, the worst were nitrates; 2 - the bacteria were also able to grow in medium without nitrogen but their activity was then by approximately 15% lower than in optimal growth conditions; 3 - in medium with KNO3 inhibition of sulfate reduction by approx. 50% was observed; 4 - the highest reduction of nitrates (removal of nitrate) in media with phosphogypsum and nitrates was at limiting concentrations of sodium lactate. This is probably caused by the selection under these conditions (low concentration of hydrogen sulfide) of denitrifying bacteria or sulfate reducing bacteria capable of using nitrates as an electron acceptor.

  13. Biotransformation and metabolic response of cyanide in weeping willows.

    PubMed

    Yu, Xiao-Zhang; Gu, Ji-Dong; Liu, Shuo

    2007-08-25

    Biotransformation and metabolic responses of plants to cyanide were investigated using pre-rooted plants of weeping willows (Salix babylonica L.) grown hydroponically in growth chambers and treated with potassium cyanide. Various physiological parameters of the plants were monitored to determine toxicity from exogenous cyanide exposure. Cyanide doses used in this study showed growth-promoting effects on plants, exhibiting higher measured values of transpiration rates, chlorophyll contents and soluble protein contents compared with the non-treated control plants. Superoxide dismutases (SOD), catalase (CAT) and peroxidase (POD) activities in leaves showed a slight change to cyanide application in most treatments. Of all selected parameters, soluble proteins of plants were the most sensitive indicator to cyanide application. Almost all applied cyanide was removed from the hydroponic solution in the presence of plants in all treatment groups. Small amounts of cyanide were detected in the plant tissues. Recovery of cyanide in different compartments of plants varied significantly, root being the dominant sink for cyanide accumulation. Mass balance studies showed that >97% of the applied cyanide was metabolized during transport through weeping willows and the metabolic rates of cyanide by plants were linearly increased with increasing of cyanide applied in the growth media. Results from this study indicated that neither visible toxic symptom nor metabolic lesion was observed for the plants after 192h of exposure, largely due to the well-established detoxification systems in willows. These findings suggest that cyanide has a beneficial role in plants and phytoremediation is a desirable solution of treating environmental sites contaminated with cyanide.

  14. Trends in study design and the statistical methods employed in a leading general medicine journal.

    PubMed

    Gosho, M; Sato, Y; Nagashima, K; Takahashi, S

    2017-07-27

    Study design and statistical methods have become core components of medical research, and the methodology has become more multifaceted and complicated over time. The study of the comprehensive details and current trends of study design and statistical methods is required to support the future implementation of well-planned clinical studies providing information about evidence-based medicine. Our purpose was to illustrate study design and statistical methods employed in recent medical literature. This was an extension study of Sato et al. (N Engl J Med 2017; 376: 1086-1087), which reviewed 238 articles published in 2015 in the New England Journal of Medicine (NEJM) and briefly summarized the statistical methods employed in NEJM. Using the same database, we performed a new investigation of the detailed trends in study design and individual statistical methods that were not reported in the Sato study. Due to the CONSORT statement, prespecification and justification of sample size are obligatory in planning intervention studies. Although standard survival methods (eg Kaplan-Meier estimator and Cox regression model) were most frequently applied, the Gray test and Fine-Gray proportional hazard model for considering competing risks were sometimes used for a more valid statistical inference. With respect to handling missing data, model-based methods, which are valid for missing-at-random data, were more frequently used than single imputation methods. These methods are not recommended as a primary analysis, but they have been applied in many clinical trials. Group sequential design with interim analyses was one of the standard designs, and novel design, such as adaptive dose selection and sample size re-estimation, was sometimes employed in NEJM. Model-based approaches for handling missing data should replace single imputation methods for primary analysis in the light of the information found in some publications. Use of adaptive design with interim analyses is increasing

  15. Bioaccumulation and biotransformation of polycyclic aromatic hydrocarbons during sediment tests with oligochaetes (Lumbriculus variegatus).

    PubMed

    Lyytikäinen, Merja; Pehkonen, Sari; Akkanen, Jarkko; Leppänen, Matti; Kukkonen, Jussi V K

    2007-12-01

    In some kinetic studies with aquatic invertebrates, the bioaccumulation of polyaromatic hydrocarbons (PAHs) has been observed to peak at the beginning of the test. This has been explained by the depletion of PAHs from pore water due to limited desorption during the bioaccumulation test or, alternatively, by the activation of biotransformation mechanisms in the organisms. In the present study, we exposed the aquatic oligochaetes, Lumbriculus variegatus, to creosote oil-contaminated sediments to examine the bioaccumulation of PAHs and to clarify the importance of contaminant depletion and biotransformation for it. The contaminant depletion was studied by replanting test organisms into fresh, nondepleted test sediments at 3-d intervals over 12 d and by comparing the resulting body burdens to those of the organisms that were not replanted. The biotransformation capability of L. variegatus was assessed by following the concentration of 1-hydroxypyrene (1-HP), a phase I metabolite of pyrene, in oligochaete tissue during a 15-d test. We observed that the bioaccumulation of most PAHs indeed peaked at the beginning of the test. The concentrations in the replanted organisms were only 1.5 to 2 times higher than in nonreplanted organisms during the first 9 d of the test and, by day 12, no differences were detected. 1-Hydroxypyrene was detected in oligochaete tissue throughout the exposures, and concentrations decreased over time. However, the proportion of 1-HP to pyrene increased linearly during the test. These results indicated that the depletion of contaminants has only a minor effect on their bioaccumulation in oligochaetes and that the cause for the observed bioaccumulation curve shape is rapid elimination of the contaminants and, possibly to some degree, their metabolites.

  16. Evaluating Employability Skills: Employer and Student Perceptions

    ERIC Educational Resources Information Center

    Saunders, Venetia; Zuzel, Katherine

    2010-01-01

    Graduate employability is a key issue for Higher Education. In this two-part study student employability skills have been evaluated from the perspective of sandwich students and graduates in biomolecular science, and their employers. A strong correlation was found between employer and sandwich student/graduate perceptions of the relative…

  17. Evaluating Employability Skills: Employer and Student Perceptions

    ERIC Educational Resources Information Center

    Saunders, Venetia; Zuzel, Katherine

    2010-01-01

    Graduate employability is a key issue for Higher Education. In this two-part study student employability skills have been evaluated from the perspective of sandwich students and graduates in biomolecular science, and their employers. A strong correlation was found between employer and sandwich student/graduate perceptions of the relative…

  18. Employment and insurance in survivors of Hodgkin lymphoma and their siblings: a questionnaire study.

    PubMed

    Chen, Aileen B; Feng, Yang; Neuberg, Donna; Recklitis, Christopher; Diller, Lisa R; Mauch, Peter N; Ng, Andrea K

    2012-08-01

    Using a questionnaire study, we compared the employment and insurance of Hodgkin lymphoma (HL) survivors versus their siblings. A total of 511 survivors and 224 siblings completed questionnaires. HL survivors were more likely to report job denial, difficulty obtaining insurance due to medical history, and difficulty changing jobs due to fear of losing insurance. On multivariable analysis, male gender, income and scarring of the head and neck were associated with job denial. Male gender and impairment interfering with a job were associated with difficulty obtaining health insurance. Survivors with >4 physician visits in 2 years, <10years from diagnosis, or with permanent hair loss from treatment were more likely to report inability to change jobs due to fear of losing insurance. Compared to their siblings, HL survivors may face greater challenges in obtaining employment and insurance. Late effects from treatment, including permanent cosmetic changes, may contribute to these differences.

  19. A qualitative study of stress in individuals self-employed in solo businesses.

    PubMed

    Schonfeld, Irvin Sam; Mazzola, Joseph J

    2015-10-01

    This qualitative study involved 54 individuals who were self-employed in a variety of solo businesses. All participants were administered a semistructured interview that inquired into various aspects of their work experience with the data subject to reliability and validity checks. The study identified stressful incidents, coping strategies, and emotional strains arising from those stressful incidents. Uncertainty about income was a common background stressor. Recent specific stressors included dramatic slowdowns in business, reputational threat, betrayal, unreasonable customers, and medical problems. Commonly occurring strains included apprehension/anxiety, frustration, anger, and sadness/depression. The self-employed used problem-focused coping much more often than emotion-focused coping. We also identified a third kind of coping that we labeled humanitarian coping. A number of questions/hypotheses for future research emerged, including identifying (a) a tipping point bearing on when the psychological benefits of self-employment (e.g., autonomy) are overtaken by business losses outside the individual's control and (b) the coping strategies that are most useful in managing work-related stressors.

  20. Longitudinal study of negative workplace events among employed rheumatoid arthritis patients and healthy controls.

    PubMed

    Mancuso, Carol A; Rincon, Melina; Sayles, Wendy; Paget, Stephen A

    2005-12-15

    Most studies of employment in patients with rheumatoid arthritis (RA) have focused on job loss. Less is known about workplace events in patients who continued to work. The goal of this longitudinal study was to compare the incidence of negative workplace events between employed patients with RA and healthy controls. Participants completed the work domains of the Psychiatric Epidemiology Research Interview Life Events Scale and the Inventory of Small Life Events Scale measuring major and minor workplace events. Events were compared between groups according to psychosocial, clinical, and job characteristics. A total of 122 patients with RA and 122 healthy controls were enrolled with similar demographic and occupational characteristics. There were no differences in percentages of patients and controls who had at least 1 major (35% versus 31%) or 1 minor (48% versus 55%) negative event. For patients with RA, negative events were associated with having more pain, more fatigue, more social stress, and less job autonomy (P < or = 0.05). For controls, in addition to social stress, negative events were associated with job characteristics, functional status, and social support (P < or = 0.05). A comparable number of patients with RA and controls had negative workplace events. In addition to the well-known contributions of job autonomy and pain, social stress and fatigue also were found to be important variables related to negative events in patients with RA. These potentially modifiable variables have not been fully evaluated with respect to long-term employment in these patients.

  1. Job Design, Employment Practices and Well-being: a Systematic Review of Intervention Studies.

    PubMed

    Daniels, Kevin; Gedikli, Cigdem; Watson, David; Semkina, Antonina; Vaughn, Oluwafunmilayo

    2017-03-08

    There is inconsistent evidence that deliberate attempts to improve job design realise improvements in well-being. We investigated the role of other employment practices, either as instruments for job redesign or as instruments that augment job redesign. Our primary outcome was well-being. Where studies also assessed performance, we considered performance as an outcome. We reviewed 33 intervention studies. We found that well-being and performance may be improved by: training workers to improve their own jobs; training coupled with job redesign; and system wide approaches that simultaneously enhance job design and a range of other employment practices. We found insufficient evidence to make any firm conclusions concerning the effects of training managers in job redesign and that participatory approaches to improving job design have mixed effects. Successful implementation of interventions was associated with worker involvement and engagement with interventions, managerial commitment to interventions and integration of interventions with other organisational systems. Practitioner summary: Improvements in well-being and performance may be associated with system-wide approaches that simultaneously enhance job design, introduce a range of other employment practices and focus on worker welfare. Training may have a role in initiating job redesign or augmenting the effects of job design on well-being.

  2. Biotransformation and Volatilization of Arsenic by Three Photosynthetic Cyanobacteria1

    PubMed Central

    Yin, Xi-Xiang; Chen, Jian; Qin, Jie; Sun, Guo-Xin; Rosen, Barry P.; Zhu, Yong-Guan

    2011-01-01

    Arsenic (As) is a pervasive and ubiquitous environmental toxin that has created worldwide human health problems. However, there are few studies about how organisms detoxify As. Cyanobacteria are capable of both photolithotrophic growth in the light and heterotrophic growth in the dark and are ubiquitous in soils, aquatic systems, and wetlands. In this study, we investigated As biotransformation in three cyanobacterial species (Microcystis sp. PCC7806, Nostoc sp. PCC7120, and Synechocystis sp. PCC6803). Each accumulated large amounts of As, up to 0.39 g kg−1 dry weight, 0.45 g kg−1 dry weight, and 0.38 g kg−1 dry weight when treated with 100 μm sodium arsenite for 14 d, respectively. Inorganic arsenate and arsenite were the predominant species, with arsenate making up >80% of total As; methylated arsenicals were detected following exposure to higher As concentrations. When treated with arsenate for 6 weeks, cells of each cyanobacterium produced volatile arsenicals. The genes encoding the As(III) S-adenosylmethionine methyltransferase (ArsM) were cloned from these three cyanobacteria. When expressed in an As-hypersensitive strain of Escherichia coli, each conferred resistance to arsenite. Two of the ArsM homologs (SsArsM from Synechocystis sp. PCC6803 and NsArsM from Nostoc sp. PCC7120) were purified and were shown to methylate arsenite in vitro with trimethylarsine as the end product. Given that ArsM homologs are widespread in cyanobacteria, we propose that they play an important role in As biogeochemistry. PMID:21562336

  3. Biotransformation and volatilization of arsenic by three photosynthetic cyanobacteria.

    PubMed

    Yin, Xi-Xiang; Chen, Jian; Qin, Jie; Sun, Guo-Xin; Rosen, Barry P; Zhu, Yong-Guan

    2011-07-01

    Arsenic (As) is a pervasive and ubiquitous environmental toxin that has created worldwide human health problems. However, there are few studies about how organisms detoxify As. Cyanobacteria are capable of both photolithotrophic growth in the light and heterotrophic growth in the dark and are ubiquitous in soils, aquatic systems, and wetlands. In this study, we investigated As biotransformation in three cyanobacterial species (Microcystis sp. PCC7806, Nostoc sp. PCC7120, and Synechocystis sp. PCC6803). Each accumulated large amounts of As, up to 0.39 g kg(-1) dry weight, 0.45 g kg(-1) dry weight, and 0.38 g kg(-1) dry weight when treated with 100 μM sodium arsenite for 14 d, respectively. Inorganic arsenate and arsenite were the predominant species, with arsenate making up >80% of total As; methylated arsenicals were detected following exposure to higher As concentrations. When treated with arsenate for 6 weeks, cells of each cyanobacterium produced volatile arsenicals. The genes encoding the As(III) S-adenosylmethionine methyltransferase (ArsM) were cloned from these three cyanobacteria. When expressed in an As-hypersensitive strain of Escherichia coli, each conferred resistance to arsenite. Two of the ArsM homologs (SsArsM from Synechocystis sp. PCC6803 and NsArsM from Nostoc sp. PCC7120) were purified and were shown to methylate arsenite in vitro with trimethylarsine as the end product. Given that ArsM homologs are widespread in cyanobacteria, we propose that they play an important role in As biogeochemistry.

  4. Ovarian Xenobiotic Biotransformation Enzymes Are Altered During Phosphoramide Mustard-Induced Ovotoxicity

    PubMed Central

    Madden, Jill A.; Keating, Aileen F.

    2014-01-01

    The anti-neoplastic prodrug, cyclophosphamide, requires biotransformation to phosphoramide mustard (PM), which partitions to volatile chloroethylaziridine (CEZ). PM and CEZ are ovotoxicants, however their ovarian biotransformation remains ill-defined. This study investigated PM and CEZ metabolism mechanisms through the utilization of cultured postnatal day 4 (PND4) Fisher 344 (F344) rat ovaries exposed to vehicle control (1% dimethyl sulfoxide (DMSO)) or PM (60μM) for 2 or 4 days. Quantification of mRNA levels via an RT2 profiler PCR array and target-specific RT-PCR along with Western blotting found increased mRNA and protein levels of xenobiotic metabolism genes including microsomal epoxide hydrolase (Ephx1) and glutathione S-transferase isoform pi (Gstp). PND4 ovaries were treated with 1% DMSO, PM (60μM), cyclohexene oxide to inhibit EPHX1 (CHO; 2mM), or PM + CHO for 4 days. Lack of functional EPHX1 increased PM-induced ovotoxicity, suggesting a detoxification role for EPHX1. PND4 ovaries were also treated with 1% DMSO, PM (60μM), BSO (Glutathione (GSH) depletion; 100μM), GEE (GSH supplementation; 2.5mM), PM ± BSO, or PM ± GEE for 4 days. GSH supplementation prevented PM-induced follicle loss, whereas no impact of GSH depletion was observed. Lastly, the effect of ovarian GSH on CEZ liberation and ovotoxicity was evaluated. Both untreated and GEE-treated PND4 ovaries were plated adjacent to ovaries receiving PM + GEE or PM + BSO treatments. Less CEZ-induced ovotoxicity was observed with both GEE and BSO treatments indicating reduced CEZ liberation from PM. Collectively, this study supports ovarian biotransformation of PM, thereby influencing the ovotoxicity that ensues. PMID:25070981

  5. Isolation and biotransformation of goniothalamin in the production of goniothalamin analogue

    NASA Astrophysics Data System (ADS)

    Azizan, Izzatul Hidayah; Khalid, Rozida Mohd; Din, Laily; Latip, Jalifah

    2016-11-01

    Goniothalamin is a pharmacologically active styrylpyrone compound extracted from Goniothalamus species. It was found to be selectively preventing proliferation of several cancer cell lines without being cytotoxic towards normal cells. Further research on this compound and its derivatives revealed that some of the derivatives also possess anti proliferative activity. The purpose of this study is to synthesise goniothalamin derivatives via biotransformation of goniothalamin using an enzyme assay. Goniothalamin which was isolated from Goniothalamus andersonii, was allowed to react with dienelactone hydrolase for 30 minutes. The enzyme reaction's product was extracted and analysed using LC-MS. Based on the pseudomelecular ion, one goniothalamin analogue with dihydro functionality was obtained.

  6. Is Increased Susceptibility to Balkan Endemic Nephropathy in Carriers of Common GSTA1 (*A/*B) Polymorphism Linked with the Catalytic Role of GSTA1 in Ochratoxin A Biotransformation? Serbian Case Control Study and In Silico Analysis

    PubMed Central

    Reljic, Zorica; Zlatovic, Mario; Savic-Radojevic, Ana; Pekmezovic, Tatjana; Djukanovic, Ljubica; Matic, Marija; Pljesa-Ercegovac, Marija; Mimic-Oka, Jasmina; Opsenica, Dejan; Simic, Tatjana

    2014-01-01

    Although recent data suggest aristolochic acid as a putative cause of Balkan endemic nephropathy (BEN), evidence also exists in favor of ochratoxin A (OTA) exposure as risk factor for the disease. The potential role of xenobiotic metabolizing enzymes, such as the glutathione transferases (GSTs), in OTA biotransformation is based on OTA glutathione adducts (OTHQ-SG and OTB-SG) in blood and urine of BEN patients. We aimed to analyze the association between common GSTA1, GSTM1, GSTT1, and GSTP1 polymorphisms and BEN susceptibility, and thereafter performed an in silico simulation of particular GST enzymes potentially involved in OTA transformations. GSTA1, GSTM1, GSTT1 and GSTP1 genotypes were determined in 207 BEN patients and 138 non-BEN healthy individuals from endemic regions by polymerase chain reaction (PCR). Molecular modeling in silico was performed for GSTA1 protein. Among the GST polymorphisms tested, only GSTA1 was significantly associated with a higher risk of BEN. Namely, carriers of the GSTA1*B gene variant, associated with lower transcriptional activation, were at a 1.6-fold higher BEN risk than those carrying the homozygous GSTA1*A/*A genotype (OR = 1.6; p = 0.037). In in silico modeling, we found four structures, two OTB-SG and two OTHQ-SG, bound in a GSTA1 monomer. We found that GSTA1 polymorphism was associated with increased risk of BEN, and suggested, according to the in silico simulation, that GSTA1-1 might be involved in catalyzing the formation of OTHQ-SG and OTB-SG conjugates. PMID:25111321

  7. Is increased susceptibility to Balkan endemic nephropathy in carriers of common GSTA1 (*A/*B) polymorphism linked with the catalytic role of GSTA1 in ochratoxin a biotransformation? Serbian case control study and in silico analysis.

    PubMed

    Reljic, Zorica; Zlatovic, Mario; Savic-Radojevic, Ana; Pekmezovic, Tatjana; Djukanovic, Ljubica; Matic, Marija; Pljesa-Ercegovac, Marija; Mimic-Oka, Jasmina; Opsenica, Dejan; Simic, Tatjana

    2014-08-08

    Although recent data suggest aristolochic acid as a putative cause of Balkan endemic nephropathy (BEN), evidence also exists in favor of ochratoxin A (OTA) exposure as risk factor for the disease. The potential role of xenobiotic metabolizing enzymes, such as the glutathione transferases (GSTs), in OTA biotransformation is based on OTA glutathione adducts (OTHQ-SG and OTB-SG) in blood and urine of BEN patients. We aimed to analyze the association between common GSTA1, GSTM1, GSTT1, and GSTP1 polymorphisms and BEN susceptibility, and thereafter performed an in silico simulation of particular GST enzymes potentially involved in OTA transformations. GSTA1, GSTM1, GSTT1 and GSTP1 genotypes were determined in 207 BEN patients and 138 non-BEN healthy individuals from endemic regions by polymerase chain reaction (PCR). Molecular modeling in silico was performed for GSTA1 protein. Among the GST polymorphisms tested, only GSTA1 was significantly associated with a higher risk of BEN. Namely, carriers of the GSTA1*B gene variant, associated with lower transcriptional activation, were at a 1.6-fold higher BEN risk than those carrying the homozygous GSTA1*A/*A genotype (OR = 1.6; p = 0.037). In in silico modeling, we found four structures, two OTB-SG and two OTHQ-SG, bound in a GSTA1 monomer. We found that GSTA1 polymorphism was associated with increased risk of BEN, and suggested, according to the in silico simulation, that GSTA1-1 might be involved in catalyzing the formation of OTHQ-SG and OTB-SG conjugates.

  8. Relative contribution of ammonia oxidizing bacteria and other members of nitrifying activated sludge communities to micropollutant biotransformation.

    PubMed

    Men, Yujie; Achermann, Stefan; Helbling, Damian E; Johnson, David R; Fenner, Kathrin

    2017-02-01

    Improved micropollutant (MP) biotransformation during biological wastewater treatment has been associated with high ammonia oxidation activities, suggesting co-metabolic biotransformation by ammonia oxidizing bacteria as an underlying mechanism. The goal of this study was to clarify the contribution of ammonia oxidizing bacteria to increased MP degradation in nitrifying activated sludge (NAS) communities using a series of inhibition experiments. To this end, we treated a NAS community with two different ammonia oxidation inhibitors, namely octyne (OCT), a mechanistic inhibitor that covalently binds to ammonia monooxygenases, and allylthiourea (ATU), a copper chelator that depletes copper ions from the active center of ammonia monooxygenases. We investigated the biotransformation of 79 structurally different MPs by the inhibitor-treated and untreated sludge communities. Fifty-five compounds exhibited over 20% removal in the untreated control after a 46 h-incubation. Of these, 31 compounds were significantly inhibited by either ATU and/or OCT. For 17 of the 31 MPs, the inhibition by ATU at 46 h was substantially higher than by OCT despite the full inhibition of ammonia oxidation by both inhibitors. This was particularly the case for almost all thioether and phenylurea compounds tested, suggesting that in nitrifying activated sludge communities, ATU does not exclusively act as an inhibitor of bacterial ammonia oxidation. Rather, ATU also inhibited enzymes contributing to MP biotransformation but not to bulk ammonia oxidation. Thus, inhibition studies with ATU tend to overestimate the contribution of ammonia-oxidizing bacteria to MP biotransformation in nitrifying activated sludge communities. Biolog tests revealed only minor effects of ATU on the heterotrophic respiration of common organic substrates by the sludge community, suggesting that ATU did not affect enzymes that were essential in energy conservation and central metabolism of heterotrophs. By comparing ATU

  9. Personality and the Gender Gap in Self-Employment: A Multi-Nation Study

    PubMed Central

    Obschonka, Martin; Schmitt-Rodermund, Eva; Terracciano, Antonio

    2014-01-01

    What role does personality play in the pervasive gender gap in entrepreneurship across the globe? This two-study analysis focuses on self-employment in the working population and underlying gender differences in personality characteristics, thereby considering both single trait dimensions as well as a holistic, configural personality approach. Applying the five-factor model of personality, Study 1, our main study, investigates mediation models in the prediction of self-employment status utilizing self-reported personality data from large-scaled longitudinal datasets collected in the U.S., Germany, the U.K., and Australia (total N = 28,762). Study 2 analyzes (observer-rated) Big Five data collected in 51 cultures (total N = 12,156) to take a more global perspective and to explore the pancultural universality of gender differences in entrepreneurial personality characteristics. Across the four countries investigated in Study 1, none of the major five dimension of personality turned out as a consistent and robust mediator. In contrast, the holistic, configural approach yielded consistent and robust mediation results. Across the four countries, males scored higher on an entrepreneurship-prone personality profile, which in turn predicted self-employment status. These results suggest that gender differences in the intra-individual configuration of personality traits contribute to the gender gap in entrepreneurship across the globe. With the restriction of limited representativeness, the data from Study 2 suggest that the gender difference in the entrepreneurship-prone personality profile (males score higher) is widespread across many cultures, but may not exist in all. The results are discussed with an emphasis on implications for research and practice, which a particular focus on the need for more complex models that incorporate the role of personality. PMID:25089706

  10. Personality and the gender gap in self-employment: a multi-nation study.

    PubMed

    Obschonka, Martin; Schmitt-Rodermund, Eva; Terracciano, Antonio

    2014-01-01

    What role does personality play in the pervasive gender gap in entrepreneurship across the globe? This two-study analysis focuses on self-employment in the working population and underlying gender differences in personality characteristics, thereby considering both single trait dimensions as well as a holistic, configural personality approach. Applying the five-factor model of personality, Study 1, our main study, investigates mediation models in the prediction of self-employment status utilizing self-reported personality data from large-scaled longitudinal datasets collected in the U.S., Germany, the U.K., and Australia (total N = 28,762). Study 2 analyzes (observer-rated) Big Five data collected in 51 cultures (total N = 12,156) to take a more global perspective and to explore the pancultural universality of gender differences in entrepreneurial personality characteristics. Across the four countries investigated in Study 1, none of the major five dimension of personality turned out as a consistent and robust mediator. In contrast, the holistic, configural approach yielded consistent and robust mediation results. Across the four countries, males scored higher on an entrepreneurship-prone personality profile, which in turn predicted self-employment status. These results suggest that gender differences in the intra-individual configuration of personality traits contribute to the gender gap in entrepreneurship across the globe. With the restriction of limited representativeness, the data from Study 2 suggest that the gender difference in the entrepreneurship-prone personality profile (males score higher) is widespread across many cultures, but may not exist in all. The results are discussed with an emphasis on implications for research and practice, which a particular focus on the need for more complex models that incorporate the role of personality.

  11. A descriptive study of employment patterns and work environment outcomes of specialist nurses in Canada.

    PubMed

    Doran, Diane; Duffield, Christine; Rizk, Paul; Nahm, Sang; Chu, Charlene H

    2014-01-01

    The purpose was to describe the number, demographic characteristics, work patterns, exit rates, and work perceptions of nurses in Ontario, Canada, in 4 specialty classifications: advanced practice nurse (APN)-clinical nurse specialist (CNS), APN-other, primary healthcare nurse practitioner [RN(extended class [EC])], and registered nurse (RN) with specialty certification. The objectives were to (1) describe how many qualified nurses are available by specialty class; (2) create a demographic profile of specialist nurses; (3) determine the proportions of specialist and nonspecialist nurses who leave (a) direct patient care and (b) nursing practice annually; (4) determine whether specialist and nonspecialist nurses differ in their self-ratings of work environment, job satisfaction, and intention to remain in nursing. Employment patterns refer to nurses' employment status (eg, full-time, part-time, casual), work duration (ie, length of employment in nurses and in current role), and work transitions (ie, movement in and out of the nursing workforce, and movement out of current role). A longitudinal analysis of the Ontario nurses' registration database from 2005 to 2010 and a survey of specialist nurses in Canada was conducted. The setting was Canada. The database sample consisted of 3 specialist groups, consisting of RN(EC), CNS, and APN-other, as well as 1 nonspecialist RN staff nurse group. The survey sample involved 359 nurses who were classified into groups based on self-reported job title and RN specialty-certification status. Data sources included College of Nurses of Ontario registration database and survey data. The study measures were the Nursing Work Index, a 4-item measure of job satisfaction, and 1-item measure of intent to leave current job. Nurses registered with the College of Nurses of Ontario were tracked over the study period to identify changes in their employment status with comparisons made between nurses employed in specialist roles and those

  12. Complementation of biotransformations with chemical C-H oxidation: copper-catalyzed oxidation of tertiary amines in complex pharmaceuticals.

    PubMed

    Genovino, Julien; Lütz, Stephan; Sames, Dalibor; Touré, B Barry

    2013-08-21

    The isolation, quantitation, and characterization of drug metabolites in biological fluids remain challenging. Rapid access to oxidized drugs could facilitate metabolite identification and enable early pharmacology and toxicity studies. Herein, we compared biotransformations to classical and new chemical C-H oxidation methods using oxcarbazepine, naproxen, and an early compound hit (phthalazine 1). These studies illustrated the low preparative efficacy of biotransformations and the inability of chemical methods to oxidize complex pharmaceuticals. We also disclose an aerobic catalytic protocole (CuI/air) to oxidize tertiary amines and benzylic CH's in drugs. The reaction tolerates a broad range of functionalities and displays a high level of chemoselectivity, which is not generally explained by the strength of the C-H bonds but by the individual structural chemotype. This study represents a first step toward establishing a chemical toolkit (chemotransformations) that can selectively oxidize C-H bonds in complex pharmaceuticals and rapidly deliver drug metabolites.

  13. Numerical study of neutron beam divergence in a beam-fusion scenario employing laser driven ions

    NASA Astrophysics Data System (ADS)

    Alejo, A.; Green, A.; Ahmed, H.; Robinson, A. P. L.; Cerchez, M.; Clarke, R.; Doria, D.; Dorkings, S.; Fernandez, J.; McKenna, P.; Mirfayzi, S. R.; Naughton, K.; Neely, D.; Norreys, P.; Peth, C.; Powell, H.; Ruiz, J. A.; Swain, J.; Willi, O.; Borghesi, M.; Kar, S.

    2016-09-01

    The most established route to create a laser-based neutron source is by employing laser accelerated, low atomic-number ions in fusion reactions. In addition to the high reaction cross-sections at moderate energies of the projectile ions, the anisotropy in neutron emission is another important feature of beam-fusion reactions. Using a simple numerical model based on neutron generation in a pitcher-catcher scenario, anisotropy in neutron emission was studied for the deuterium-deuterium fusion reaction. Simulation results are consistent with the narrow-divergence (∼ 70 ° full width at half maximum) neutron beam recently served in an experiment employing multi-MeV deuteron beams of narrow divergence (up to 30° FWHM, depending on the ion energy) accelerated by a sub-petawatt laser pulse from thin deuterated plastic foils via the Target Normal Sheath Acceleration mechanism. By varying the input ion beam parameters, simulations show that a further improvement in the neutron beam directionality (i.e. reduction in the beam divergence) can be obtained by increasing the projectile ion beam temperature and cut-off energy, as expected from interactions employing higher power lasers at upcoming facilities.

  14. Gut microbiome perturbations induced by bacterial infection affect arsenic biotransformation

    PubMed Central

    Lu, Kun; Cable, Peter Hans; Abo, Ryan Phillip; Ru, Hongyu; Graffam, Michelle E.; Schieper, Katherine Ann; Parry, Nicola M.A.; Levine, Stuart; Bodnar, Wanda M; Wishnok, John S.; Styblo, Miroslav; Swenberg, James A; Fox, James G.; Tannenbaum, Steven R.

    2014-01-01

    Exposure to arsenic affects large human populations worldwide, and has been associated with a long list of human diseases, including skin, bladder, lung, and liver cancers, diabetes, and cardiovascular disorders. In addition, there are large individual differences in susceptibility to arsenic-induced diseases, which are frequently associated with different patterns of arsenic metabolism. Several underlying mechanisms, such as genetic polymorphisms and epigenetics, have been proposed, as these factors closely impact the individuals' capacity to metabolize arsenic. In this context, the role of the gut microbiome in directly metabolizing arsenic and triggering systemic responses in diverse organs raises the possibility that perturbations of the gut microbial communities affect the spectrum of metabolized arsenic species and subsequent toxicological effects. In this study, we used an animal model with altered gut microbiome induced by bacterial infection, 16S rRNA gene sequencing and inductively coupled plasma mass spectrometry (ICP-MS)-based arsenic speciation to examine the effect of gut microbiome perturbations on the biotransformation of arsenic. Metagenomics sequencing revealed that bacterial infection significantly perturbed the gut microbiome composition in C57BL/6 mice, which in turn resulted in altered spectra of arsenic metabolites in urine, with inorganic arsenic species, methylated and thiolated arsenic being perturbed. These data clearly illustrated that gut microbiome phenotypes significantly affected arsenic metabolic reactions, including reduction, methylation and thiolation. These findings improve our understanding of how infectious diseases and environmental exposure interact, and may also provide novel insight regarding the gut microbiome composition as a new risk factor of individual susceptibility to environmental chemicals. PMID:24134150

  15. Biotransformations of Plutonium and Uranium by Naturally-Occurring Bacteria

    SciTech Connect

    Boukhalfa, Hakim; Icopini, Gary A.; Lack, Joe G.; Reilly, Sean D.; Hersman, Larry E.; Ruggiero, Christy E.; John, Seth G.; Neu, Mary P.

    2004-03-17

    DOE sites are contaminated by radionuclides and toxic metals, which are in contact with organic contaminants, reactive minerals, and diverse populations of microorganisms. Actinide species to be stabilized or mobilized in situ via direct and indirect chemical, biological, and geochemical processes. Actinide contamination tends to be broadly dispersed and present at low concentrations and therefore prohibitively costly to remove using conventional methods. Pu contamination is particularly challenging because of personnel exposure concerns and a lack of disposal sites. Bacterial bioremediation is a preferable treatment approach. Given that the radionuclides of most concern to the NABIR program are generally more mobile in their oxidized forms (e.g. Pu(VI), Pu(V), U(VI), Tc(VII), Cr(VI)), proposed biostabilization strategies are generally based upon either in situ sequestration of the oxidized form (e.g. actinide biosorption and bioaccumulation within exopolymers and biofilms) or biomineralization of the reduced form (e.g., direct or indirect production of insoluble hydroxides by DMRB). The feasibility of these approaches is affected by the speciation of actinides under environment conditions. For example, actinides can form complexes with co-contaminants (e.g. EDTA) or natural chelators like siderophores and biopolymers. Resulting complexes can interact with bacteria in several ways to yield biostabilized products or more mobile species that could persist. They are investigating how organic chelators affect the speciation and biotransformation of U and Pu. Previously, they reported how these siderophores bind, desorb and solubilize radionuclides. Here they present new results on EDTA complexation, siderophore-mediated Pu accumulation by aerobic bacteria, and initial studies of Pu reduction by DMRB.

  16. Investigation of biotransformation of selenium in plants using spectrometric methods

    NASA Astrophysics Data System (ADS)

    Ruszczyńska, Anna; Konopka, Anna; Kurek, Eliza; Torres Elguera, Julio Cesar; Bulska, Ewa

    2017-04-01

    The aim of this research was to study the processes of biotransformation of selenium in plants such as garlic, radish sprouts and sunflower sprouts via identification of selenium-containing compounds as metabolites of inorganic selenium using mass spectrometry. Speciation analysis of selenium in extracts from plant samples was performed with the use of hyphenated high performance liquid chromatography and inductively coupled plasma mass spectrometry (HPLC-ICP-MS) method. Matching the retention times of sample compounds with standards allowed identification of Se-methyl-selenocysteine, selenomethionine, γ-glutamyl-Se-methylselenocysteine and inorganic SeO32 -. However, registered chromatograms included additional 82Se signals which couldn't be identified due to the lack of standards. Qualitative analysis of unknown compounds was achieved using high-resolution mass spectrometer equipped with mass analyzer Orbitrap coupled to high performance liquid chromatography. Since selenium has six stable isotopes of different abundance in nature, mass spectra of have a very characteristic isotopic pattern. In order to elucidate the structure of unknown Se compounds, selected ions were subjected to the fragmentation. Following selenocompounds were identified an inorganic selenium metabolites in garlic, sunflower sprouts and/or radish sprouts: selenohomolanthionine, Se-methyl-selenocysteine, selenomethionine, selenomethionine oxide, deaminohydroxy-selenohomolanthionine, N-acetylcysteine-selenomethionine, γ-glutamyl-Se-methyl-selenocysteine, methylseleno-Se-pentose-hexose, Se-methyl-selenoglutathione, 2,3-dihydroxy-propionyl-selenocysteine-cysteine, methyltio-selenoglutathione, 2,3-dihydroxypropionyl-selenolanthionine and two Se-containing compounds with proposed molecular formula C10H18N2O6Se and C10H13N5O3Se. Moreover, the structure was proposed for one selenocompound found in sunflower sprouts which has not been reported so far.

  17. A proof-of-concept study of the "Employment and Arthritis: Making It Work" program.

    PubMed

    Lacaille, Diane; White, Margaret A; Rogers, Pam A; Backman, Catherine L; Gignac, Monique A M; Esdaile, John M

    2008-11-15

    Work disability is a common outcome of inflammatory arthritis (IA), yet few services address employment. We conducted a proof-of-concept study of the "Employment and Arthritis: Making It Work" self-management program aimed at preventing work disability and maintaining at-work productivity in employed people with IA. The program was developed using the precede-proceed model and self-management concepts. Program goals included modifying risk factors for work disability and enhancing self-management of work problems due to IA, as identified in initial focus groups. The program included a self-learning manual, 5 group sessions, and individual visits with an occupational therapist for an ergonomic assessment and a vocational rehabilitation counselor. It was pilot tested in 2 groups (n = 19) and evaluated over 12 months of followup. Participants consisted of 19 employed women with IA. Process evaluation demonstrated feasibility and excellent attendance and use of the self-learning manual. By 1 year, 80% reported increased confidence in requesting job accommodations, 74% had requested an accommodation, and 71% of requested accommodations were implemented. The occupational therapist and vocational rehabilitation counselor visits resulted in recommendations for change in 100% and 74% of participants, respectively, with implementation of some recommended changes in 89% and 63%, respectively. Improvements were observed in self-confidence in managing problems at work, fatigue interference with work, measures of limitations, and at-work productivity. We developed a novel intervention to prevent work disability in patients with IA, combining self-management group sessions and professional assessments aimed at job retention, which resulted in people making changes to adapt their work to their arthritis, and improved fatigue, self-efficacy, and at-work productivity.

  18. Role of Free Radicals and Biotransformation in Trichloronitrobenzene-Induced Nephrotoxicity In Vitro

    PubMed Central

    Rankin, Gary O.; Tyree, Connor; Pope, Deborah; Tate, Jordan; Racine, Christopher; Anestis, Dianne K.; Brown, Kathleen C.; Dial, Mason; Valentovic, Monica A.

    2017-01-01

    This study determined the comparative nephrotoxic potential of four trichloronitrobenzenes (TCNBs) (2,3,4-; 2,4,5-; 2,4,6-; and 3,4,5-TCNB) and explored the effects of antioxidants and biotransformation inhibitors on TCNB-induced cytotoxicity in isolated renal cortical cells (IRCC) from male Fischer 344 rats. IRCC were incubated with a TCNB up to 1.0 mM for 15–120 min. Pretreatment with an antioxidant or cytochrome P450 (CYP), flavin monooxygenase (FMO), or peroxidase inhibitor was used in some experiments. Among the four TCNBs, the order of decreasing nephrotoxic potential was approximately 3,4,5- > 2,4,6- > 2,3,4- > 2,4,5-TCNB. The four TCNBs exhibited a similar profile of attenuation of cytotoxicity in response to antioxidant pretreatments. 2,3,4- and 3,4,5-TCNB cytotoxicity was attenuated by most of the biotransformation inhibitors tested, 2,4,5-TCNB cytotoxicity was only inhibited by isoniazid (CYP 2E1 inhibitor), and 2,4,6-TCNB-induced cytotoxicity was inhibited by one CYP inhibitor, one FMO inhibitor, and one peroxidase inhibitor. All of the CYP specific inhibitors tested offered some attenuation of 3,4,5-TCNB cytotoxicity. These results indicate that 3,4,5-TCNB is the most potent nephrotoxicant, free radicals play a role in the TCNB cytotoxicity, and the role of biotransformation in TCNB nephrotoxicity in vitro is variable and dependent on the position of the chloro groups. PMID:28561793

  19. Role of Free Radicals and Biotransformation in Trichloronitrobenzene-Induced Nephrotoxicity In Vitro.

    PubMed

    Rankin, Gary O; Tyree, Connor; Pope, Deborah; Tate, Jordan; Racine, Christopher; Anestis, Dianne K; Brown, Kathleen C; Dial, Mason; Valentovic, Monica A

    2017-05-31

    This study determined the comparative nephrotoxic potential of four trichloronitrobenzenes (TCNBs) (2,3,4-; 2,4,5-; 2,4,6-; and 3,4,5-TCNB) and explored the effects of antioxidants and biotransformation inhibitors on TCNB-induced cytotoxicity in isolated renal cortical cells (IRCC) from male Fischer 344 rats. IRCC were incubated with a TCNB up to 1.0 mM for 15-120 min. Pretreatment with an antioxidant or cytochrome P450 (CYP), flavin monooxygenase (FMO), or peroxidase inhibitor was used in some experiments. Among the four TCNBs, the order of decreasing nephrotoxic potential was approximately 3,4,5- > 2,4,6- > 2,3,4- > 2,4,5-TCNB. The four TCNBs exhibited a similar profile of attenuation of cytotoxicity in response to antioxidant pretreatments. 2,3,4- and 3,4,5-TCNB cytotoxicity was attenuated by most of the biotransformation inhibitors tested, 2,4,5-TCNB cytotoxicity was only inhibited by isoniazid (CYP 2E1 inhibitor), and 2,4,6-TCNB-induced cytotoxicity was inhibited by one CYP inhibitor, one FMO inhibitor, and one peroxidase inhibitor. All of the CYP specific inhibitors tested offered some attenuation of 3,4,5-TCNB cytotoxicity. These results indicate that 3,4,5-TCNB is the most potent nephrotoxicant, free radicals play a role in the TCNB cytotoxicity, and the role of biotransformation in TCNB nephrotoxicity in vitro is variable and dependent on the position of the chloro groups.

  20. Toxicity and biotransformation of uncoated and coated nickel hydroxide nanoparticles on mesquite plants.

    PubMed

    Parsons, Jason G; Lopez, Martha L; Gonzalez, Christina M; Peralta-Videa, Jose R; Gardea-Torresdey, Jorge L

    2010-05-01

    Nanomaterials are of particular interest in environmental chemistry due to their unknown toxicity to living organisms. Reports indicate that nanoparticles (NPs) affect seed germination, but the uptake and biotransformation of metal nanoparticles is not well understood. The present study investigated the toxicity and biotransformation of Ni(OH)2 NPs by mesquite plants (Prosopis sp.). Three sets of plants were treated for four weeks with 0.01, 0.05, or 0.10 g of either uncoated or sodium citrate coated NPs before and after synthesis. Nickel concentrations in plants were determined by inductively coupled plasma-optical emission spectroscopy (ICP-OES) and the form and oxidation state of Ni was determined using X-ray absorption spectroscopy (XAS). Results showed that uncoated NPs had an average size of 8.7 nm, whereas coated NPs before and after synthesis had an average of 2.5 and 0.9 nm, respectively. The ICP-OES results showed that plants treated with 0.10 g of uncoated and coated NPs before and after synthesis had 803, 764, and 400 mg Ni kg dry weight, in the leaves, respectively. The XAS analyses showed Ni NPs in roots and shoots of plants treated with uncoated NPs, whereas leaves showed a Ni(II)-organic acid type complex. However, plants treated with coated NPs before or after synthesis showed Ni NPs only in roots and a Ni(II)-organic acid complex in shoots and leaves. Results also showed that none of the treatments reduced plant size or chlorophyll production. To the authors' knowledge, this is the first time that the biotransformation of nanoparticles by a plant system is reported. Copyright (c) 2010 SETAC.

  1. Menthol and geraniol biotransformation and glycosylation capacity of Levisticum officinale hairy roots.

    PubMed

    Nunes, Inês S; Faria, Jorge M S; Figueiredo, A Cristina; Pedro, Luis G; Trindade, Helena; Barroso, José G

    2009-03-01

    The biotransformation capacity of Levisticum officinale W.D.J. Koch hairy root cultures was studied by evaluating the effect of the addition of 25 mg/L menthol or geraniol on morphology, growth, and volatiles production. L. officinale hairy root cultures were maintained for 7 weeks in SH medium, in darkness at 24 degrees C and 80 r.p.m., and the substrates were added 15 days after inoculation. Growth was evaluated by measuring fresh and dry weight and by using the dissimilation method. Volatiles composition was analyzed by GC and GC-MS. Hairy roots morphology and growth were not influenced by substrate addition. No new volatiles were detected after menthol addition and, as was also the case with the control cultures, volatiles of these hairy roots were dominated by (Z)-falcarinol (1-45%), N-octanal (3-8%), palmitic acid (3-10%), and (Z)-ligustilide (2-9%). The addition of geraniol induced the production of six new volatiles: nerol/citronellol/neral (traces-15%), alpha-terpineol (0.2-3%), linalool (0.1-1.2%), and geranyl acetate (traces-2%). The relative amounts of the substrates and some of their biotransformation products decreased during the course of the experiment. Following the addition of beta-glycosidase to the remaining distillation water, analysis of the extracted volatiles showed that lovage hairy roots were able to convert both substrates and their biotransformation products into glycosidic forms. GC:gas chromatography GC-MS:gas chromatography-mass spectrometry SH:Schenk and Hildebrandt (1972) culture medium.

  2. Bioaccumulation and biotransformation of the beta-blocker propranolol in multigenerational exposure to Daphnia magna.

    PubMed

    Jeong, Tae-Yong; Kim, Tae-Hun; Kim, Sang Don

    2016-09-01

    Multigenerational bioaccumulation and biotransformation activity and short-term kinetics (e.g., uptake and depuration) of propranolol in Daphnia magna were investigated at environmental concentration. The body burden and the major metabolite, desisopropyl propranolol (DIP), of propranolol were quantified using LC-MS/MS at the end of each generation after exposure for 11 generations. The accumulation of propranolol in D. magna at an environmental concentration of 0.2 μg/L was not much different between the parent (F0) and the eleventh filial (F10) generation. However, at 28 μg/L, its accumulation was 1.6 times higher-up to 18.9 μg/g-in the F10 generation relative to the F0. In contrast to propranolol, DIP intensity gradually increased from F0 to F10 at 0.2 μg/L, reflecting an increase in detoxification load and biotransformation performance; no increasing trend was observed at 28 μg/L. The bioaccumulation factor (BAF) showed higher values with a lower concentration and longer period of exposure. The average values of the BAF for 21 days of long-term exposure in successive 11 generations were 440.4 ± 119.7 and 1026.5 ± 208.6 L/kg for 28 μg/L and 0.2 μg/L, respectively. These are comparable to the BAF of 192 for the short-term 72-h exposure at 28 μg/L in the parent generation. It is also recommended that future studies for pharmaceutical ingredients be conducted on drug-drug interaction and structural characteristics on the prediction of biotransformation activity and bioaccumulation rate.

  3. PAH biotransformation in terrestrial invertebrates--a new phase II metabolite in isopods and springtails.

    PubMed

    Stroomberg, Gerard J; Zappey, Herman; Steen, Ruud J C A; van Gestel, Cornelis A M; Ariese, Freek; Velthorst, Nel H; van Straalen, Nico M

    2004-06-01

    Soil-living invertebrates are exposed to high concentrations of contaminants accumulating in dead organic matter, such as polycyclic aromatic hydrocarbons (PAHs). The capacity for PAH biotransformation is not equally developed in all invertebrates. In this paper, we compare three species of invertebrates, Porcellio scaber (Isopoda), Eisenia andrei (Lumbricidae) and Folsomia candida (Collembola), for the metabolites formed upon exposure to pyrene. Metabolic products of pyrene biotransformation in extracts from whole animals or isopod hepatopancreas were compared to those found in fish bile (flounder and plaice). An optimized HPLC method was used with fluorescence detection; excitation/emission spectra were compared to reference samples of 1-hydroxypyrene and enzymatically synthesized conjugates. Enzymatic hydrolysis after fractionation was used to demonstrate that the conjugates originated from 1-hydroxypyrene. All three invertebrates were able to oxidize pyrene to 1-hydroxypyrene, however, isopods and collembolans stood out as more efficient metabolizers compared to earthworms. In contrast to fish, none of the invertebrates produced pyrene-1-glucuronide as a phase II conjugate. Both Collembola and Isopoda produced significant amounts of pyrene-1-glucoside, whereas isopods also produced pyrene-1-sulfate. A third, previously unknown, conjugate was found in both isopods and springtails, and was analysed further using electrospray and atmospheric pressure chemical ionisation mass spectrometry. Based on the obtained mass spectra, a new conjugate is proposed: pyrene-1-O-(6"-O-malonyl)glucoside. The use of glucose-malonate as a conjugant in animal phase II biotransformation has not been described before, but is understandable in the microenvironment of soil-living invertebrates. In the earthworm, three other pyrene metabolites were observed, none of which was shared with the arthropods, although two were conjugates of 1-hydroxypyrene. Our study illustrates the great

  4. Effects of tributyltin (TBT) on in vitro hormonal and biotransformation responses in Atlantic salmon (Salmo salar).

    PubMed

    Mortensen, Anne S; Arukwe, Augustine

    2009-01-01

    The mechanisms by which the biocide tributyltin (TBT) and its metabolites affect the hormonal and xenobiotic biotransformation pathways in aquatic species are not well understood. In this study hepatocytes isolated from salmon were used to evaluate the mechanistical effects of TBT on fish hormonal and xenobiotic biotransformation pathways. Cells were exposed to 0.01, 0.1, 1, or 5 microM TBT and samples were collected at 0, 12, 24, or 48 h following exposure. Gene expression patterns were evaluated using quantitative polymerase chain reaction (PCR), and cytochrome P-450 (CYP)-mediated enzyme activities were evaluated by ethoxyresorufin, benzyloxyresorufin, and pentoxyresorufin O-deethylase (EROD, BROD, and PROD, respectively) activity assays. Generally, exposure of hepatocytes to 1 microM (at 48 h) and 5 microM TBT (at 12, 24, and 48 h) consistently produced reductions in all mRNA species investigated. TBT produced significant decreases of vitellogen (Vtg) expression at 48 h and modified the expression patterns of estrogen receptors (ERalpha and ERbeta) and androgen receptor-beta (ARbeta) that were dependent on time and TBT concentration. In the xenobiotic biotransformation pathway, TBT produced differential expression patterns that were dependent on exposure time and concentration for all salmonid AhR2 isoforms (AhR2alpha, AhR2beta, AhR2delta, and AhR2gamma). For CYP1A1, CYP3A, AhRR, and Arnt mRNA, TBT produced exposure- and time-specific modulations. Catalytic CYP activities showed that BROD activity increased in an apparent concentration-specific manner in cells exposed to TBT for 12 h. Interestingly, EROD activity showed a TBT concentration-dependent increase at 24 h and PROD at 12 and 48 h of exposure. In general our data show that TBT differentially modulated hormonal and biotransformation responses in the salmon in vitro system. The apparent and consistent decrease of the studied responses with time in 1 and 5 microM exposed hepatocytes suggest a possible

  5. The potential of indigenous Paenibacillus ehimensis BS1 for recovering heavy crude oil by biotransformation to light fractions.

    PubMed

    Shibulal, Biji; Al-Bahry, Saif N; Al-Wahaibi, Yahya M; Elshafie, Abdulkadir E; Al-Bemani, Ali S; Joshi, Sanket J

    2017-01-01

    potential of P. ehimensis BS1 in MEOR technology by the biotransformation of heavy to lighter crude oil under aerobic and reservoir conditions. Heavy oil recovery and biotransformation to lighter components are of great economic value and a few studies have been done.

  6. The potential of indigenous Paenibacillus ehimensis BS1 for recovering heavy crude oil by biotransformation to light fractions

    PubMed Central

    Shibulal, Biji; Al-Bahry, Saif N.; Al-Wahaibi, Yahya M.; Elshafie, Abdulkadir E.; Al-Bemani, Ali S.; Joshi, Sanket J.

    2017-01-01

    potential of P. ehimensis BS1 in MEOR technology by the biotransformation of heavy to lighter crude oil under aerobic and reservoir conditions. Heavy oil recovery and biotransformation to lighter components are of great economic value and a few studies have been done. PMID:28196087

  7. 6:2 and 8:2 fluorotelomer alcohol anaerobic biotransformation in digester sludge from a WWTP under methanogenic conditions.

    PubMed

    Zhang, Shu; Szostek, Bogdan; McCausland, Patricia K; Wolstenholme, Barry W; Lu, Xiaoxia; Wang, Ning; Buck, Robert C

    2013-05-07

    6:2 FTOH and 8:2 FTOH [FTOHs, F(CF2)nCH2CH2OH, n = 6, 8] are the principal polyfluorinated raw materials used to manufacture FTOH-based products, which may be released to WWTPs during their product life cycle. For the first time, anaerobic biotransformation of FTOHs and key biotransformation intermediates in WWTP digester sludge under methanogenic conditions was investigated. 6:2 FTOH was transformed to 6:2 FTCA, [F(CF2)6CH2COOH, 32-43 mol %], 6:2 FTUCA [F(CF2)5CF═CHCOOH, 1.8-8.0 mol %], and 5:3 acid [F(CF2)5CH2CH2COOH, 18-23 mol %] by day 90 and day 176 in two separate studies. 8:2 FTOH was transformed by day 181 to 8:2 FTCA (18 mol %), 8:2 FTUCA (5.1 mol %), and 7:3 acid (27 mol %). 6:2 and 8:2 FTOH anaerobic biotransformation led to low levels of perfluorohexanoic acid (PFHxA, ≤0.4 mol %) and perfluorooctanoic acid (PFOA, 0.3 mol %), respectively. 6:2 FTUCA anaerobic biotransformation led to a newly identified novel transient intermediate 3-fluoro 5:3 acid [F(CF2)5CFHCH2COOH] and 5:3 acid, but not 5:2 sFTOH [F(CF2)5CH(OH)CH3] and α-OH 5:3 acid [F(CF2)5CH2CH(OH)COOH], two precursors leading to PFPeA (perfluoropentanoic acid) and PFHxA. Thus, FTOH anaerobic biotransformation pathways operated by microbes in the environment was likely inefficient at shortening carbon chains of FTOHs to form PFCAs (perfluorinated carboxylic acids). These results imply that anaerobic biotransformation of FTOH-based products may produce polyfluorinated acids, but is not likely a major source of PFCAs detected in anaerobic environmental matrices such as anaerobic digester sludge, landfill leachate, and anaerobic sediment under methanogenic conditions.

  8. Biotransformation of Furanic and Phenolic Compounds with Hydrogen Gas Production in a Microbial Electrolysis Cell.

    PubMed

    Zeng, Xiaofei; Borole, Abhijeet P; Pavlostathis, Spyros G

    2015-11-17

    Furanic and phenolic compounds are problematic byproducts resulting from the breakdown of lignocellulosic biomass during biofuel production. The capacity of a microbial electrolysis cell (MEC) to produce hydrogen gas (H2) using a mixture of two furanic (furfural, FF; 5-hydroxymethyl furfural, HMF) and three phenolic (syringic acid, SA; vanillic acid, VA; and 4-hydroxybenzoic acid, HBA) compounds as the substrate in the bioanode was assessed. The rate and extent of biotransformation of the five compounds and efficiency of H2 production, as well as the structure of the anode microbial community, were investigated. The five compounds were completely transformed within 7-day batch runs and their biotransformation rate increased with increasing initial concentration. At an initial concentration of 1200 mg/L (8.7 mM) of the mixture of the five compounds, their biotransformation rate ranged from 0.85 to 2.34 mM/d. The anode Coulombic efficiency was 44-69%, which is comparable to that of wastewater-fed MECs. The H2 yield varied from 0.26 to 0.42 g H2-COD/g COD removed in the anode, and the bioanode volume-normalized H2 production rate was 0.07-0.1 L/L-d. The biotransformation of the five compounds took place via fermentation followed by exoelectrogenesis. The major identified fermentation products that did not transform further were catechol and phenol. Acetate was the direct substrate for exoelectrogenesis. Current and H2 production were inhibited at an initial substrate concentration of 1200 mg/L, resulting in acetate accumulation at a much higher level than that measured in other batch runs conducted with a lower initial concentration of the five compounds. The anode microbial community consisted of exoelectrogens, putative degraders of the five compounds, and syntrophic partners of exoelectrogens. The MEC H2 production demonstrated in this study is an alternative to the currently used process of reforming natural gas to supply H2 needed to upgrade bio-oils to stable

  9. Predictors of sickness absence in college and university educated self-employed: a historic register study.

    PubMed

    Wijnvoord, Liesbeth E C; Van der Klink, Jac J L; De Boer, Michiel R; Brouwer, Sandra

    2014-05-02

    Despite a large proportion of the workforce being self-employed, few studies have been conducted on risk factors for sickness absence in this population. The aim of this study is to identify risk factors for future sickness absence in a population of college and university educated self-employed. In a historic register study based on insurance company files risk factors were identified by means of logistic regression analysis. Data collected at application for private disability insurance from 634 applicants were related to subsequent sickness absence periods of 30 days or more during a follow-up period of 7.95 years. Variables studied were self-reported lifestyle variables, variables concerning medical history and present health conditions and variables derived from the general medical examination including blood tests and urinary analysis. Results from analysis of data from 634 applicants for private disability insurance show that previous periods of sickness absence (OR 2.07), female gender (OR 2.04), health complaints listed in the health declaration (OR 1.88), elevated erythrocyte sedimentation rate (ESR) (OR 4.05) and the nature of the profession were related to a higher risk of sickness absence. Sickness absence was found to be related to demographic variables (gender, profession), medical variables (health complaints and erythrocyte sedimentation rate) and to variables with both a medical and a behavioural component (previous sickness absence).

  10. Cooperative Home Care Associates: A Case Study of a Sectoral Employment Development Approach. Sectoral Employment Development Learning Project Case Studies Series.

    ERIC Educational Resources Information Center

    Inserra, Anne; Conway, Maureen; Rodat, John

    Cooperative Home Care Associates (CHCA) is a worker-owned cooperative and employer-based training program that provides home health aide services in New York City's South Bronx. Since 1985, CHCA has developed from an outsider advocating for change in the home health sector to an insider within the sector. CHCA exhibits the following…

  11. Migration, employment and the urban labour market: a study in the Indian Punjab.

    PubMed

    Oberai, A S; Manmohan Singh, H K

    1984-01-01

    "Fears are often expressed that migration to the towns is a cause of surplus labour, increased unemployment, and the general decline in the quality of life in urban areas. In a detailed study of the interaction between migration and the urban labour market in an Indian city, the authors investigate these questions and show how the migrants fare as compared with the urban natives. They find no evidence that migrants are confined to marginal employment or contribute disproportionately to urban underemployment. Policy-makers are cautioned against adopting measures to curb migration, which is part of the process of economic growth and social advance, without first making a detailed assessment of its effects."

  12. The Relationship between Employer Endorsement of Continuing Education and Training and Work and Study Performance: A Hong Kong Case Study

    ERIC Educational Resources Information Center

    Hung, Humphry; Wong, Yiu Hing

    2007-01-01

    Based on psychological contract theory and expectancy disconfirmation theory, we posit that if employers support their staff by endorsing their continuing education and training, these employees will in turn be more satisfied and will perform better not only in their studies but also in their jobs. We also propose that such an endorsement will…

  13. The Relationship between Employer Endorsement of Continuing Education and Training and Work and Study Performance: A Hong Kong Case Study

    ERIC Educational Resources Information Center

    Hung, Humphry; Wong, Yiu Hing

    2007-01-01

    Based on psychological contract theory and expectancy disconfirmation theory, we posit that if employers support their staff by endorsing their continuing education and training, these employees will in turn be more satisfied and will perform better not only in their studies but also in their jobs. We also propose that such an endorsement will…

  14. Youth who neither study nor work: mental health, education and employment.

    PubMed

    Benjet, Corina; Hernández-Montoya, Dewi; Borges, Guilherme; Méndez, Enrique; Medina-Mora, María Elena; Aguilar-Gaxiola, Sergio

    2012-01-01

    Limited educational and job opportunities for youth has led to a phenomenon termed NEET (not in education, employment or training). The objective is to estimate the prevalence of psychiatric disorders, substance use and suicidal behavior in youth classified as NEET and to compare with those who study only, work only or do both. 3 005 12-to-17 year-olds in Mexico City were evaluated in 2005 with the Composite International Diagnostic Interview. Descriptive and logistic regression analyses considered the multistage weighted sample design. NEET youth as well as those who work only or study and work simultaneously have greater odds of psychiatric disorder, substance use and suicidal behavior compared to those who study exclusively even after controlling for social disadvantage. Vulnerability is not circumscribed to NEET adolescents, but to all teens who are not exclusive students. Supporting youth to continue studying exclusively may buffer negative mental health outcomes.

  15. Usability engineering for augmented reality: employing user-based studies to inform design.

    PubMed

    Gabbard, Joseph L; Swan, J Edward

    2008-01-01

    A major challenge, and thus opportunity, in the field of human-computer interaction and specifically usability engineering is designing effective user interfaces for emerging technologies that have no established design guidelines or interaction metaphors or introduce completely new ways for users to perceive and interact with technology and the world around them. Clearly, augmented reality is one such emerging technology. We propose a usability engineering approach that employs user-based studies to inform design, by iteratively inserting a series of user-based studies into a traditional usability engineering lifecycle to better inform initial user interface designs. We present an exemplar user-based study conducted to gain insight into how users perceive text in outdoor augmented reality settings and to derive implications for design in outdoor augmented reality. We also describe lessons learned from our experiences conducting user-based studies as part of the design process.

  16. Temporal stability of objective structured clinical exams: a longitudinal study employing item response theory

    PubMed Central

    2012-01-01

    Background The objective structure clinical examination (OSCE) has been used since the early 1970s for assessing clinical competence. There are very few studies that have examined the psychometric stability of the stations that are used repeatedly with different samples. The purpose of the present study was to assess the stability of objective structured clinical exams (OSCEs) employing the same stations used over time but with a different sample of candidates, SPs, and examiners. Methods At Time 1, 191 candidates and at Time 2 (one year apart), 236 candidates participated in a 10-station OSCE; 6 of the same stations were used in both years. Generalizability analyses (Ep2) were conducted. Employing item response analyses, test characteristic curves (TCC) were derived for each of the 6 stations for a 2-parameter model. The TCCs were compared across the two years, Time 1 and 2. Results The Ep2 of the OSCEs exceeded.70. Standardized thetas (θ) and discriminations were equivalent for the same station across the two year period indicating equivalent TCCs for a 2-parameter model. Conclusion The 6 OSCE stations used by the AIMG program over two years have adequate internal consistency reliability, stable generalizability (Ep2) and equivalent test characteristics. The process of assessment employed for IMG’s are stable OSCE stations that may be used several times over without compromising psychometric properties. With careful security, high-stakes OSCEs may use the same stations that have high internal consistency and generalizability repeatedly as the psychometric properties are stable over several years with different samples of candidates. PMID:23216816

  17. [Mortality study in a cohort of workers employed in a plant producing sulphuric acid ].

    PubMed

    Pesatori, Angela Cecilia; Consonni, D; Rubagotti, Maurizia; Bonzini, M; Catalano, P; Bertazzi, P A

    2006-01-01

    In 1992, the International Agency for Research on Cancer (IARC) classified sulphuric acid mists as human carcinogen, based primarily on human data showing increased risk for larynx cancer. Uncertainties still exist about other respiratory cancers. We carried out a historical mortality study among workers ofa plant producing sulphuric acid in Tuscany, Italy. We reconstructed a cohort of 1372 male and 37female workers with at least one year of employment at the plant in the period 1962-97; 46% ofthe workers had previously been working in pyrite mines in the area where rocks have a high silica content. Environmental measurements of sulphuric acid and sulphur dioxide from the 1970's were generally below the TLVs. Mortality was investigated as of August 2000; Standardized Mortality Ratios (SMR) were calculated using Tuscany reference rates. Overall mortality was below expectation (SMR 77). In labourers, larynx cancer deaths were 4 vs 3.1 expected (SMR 130, 95% CI 35-333), while mortality from lung cancer was below expectation (27/32.8, SMR 82, 95% CI 54-120). An excess of myeloid leukaemia was observed mainly in workers without previous experience in mines (3/0.6, SMR 523, 95% CI 108-1527). Mortality from silicosis, but not from lung cancer, was remarkably high among workers with previous employment in mines. Among workers employed in sulphuric acid production, with or without previous experience in mines, we did not observe increased mortality from larynx or lung cancer. The increased mortality from myeloid leukaemia cannot be attributed to any of the exposures documented in the study plant and requires further investigation.

  18. Biotransformation of citrus aromatics nootkatone and valencene by microorganisms.

    PubMed

    Furusawa, Mai; Hashimoto, Toshihiro; Noma, Yoshiaki; Asakawa, Yoshinori

    2005-11-01

    Biotransformations of the sesquiterpene ketone nootkatone from the crude drug Alpiniae Fructus and grapefruit oil, and the sesquiterpene hydrocarbon valencene from Valencia orange oil were carried out with microorganisms such as Aspergillus niger, Botryosphaeria dothidea, and Fusarium culmorum to afford structurally interesting metabolites. Their stereostructures were established by a combination of high-resolution NMR spectral and X-ray crystallographic analysis and chemical reaction. Metabolic pathways of compounds and by A. niger are proposed.

  19. Fungal biotransformation of crude glycerol into malic acid.

    PubMed

    West, Thomas P

    2015-01-01

    Malic acid production from the biodiesel coproduct crude glycerol by Aspergillus niger ATCC 9142, ATCC 10577 and ATCC 12846 was observed to occur with the highest malic acid level acid being produced by A. niger ATCC 12846. Fungal biomass production from crude glycerol was similar, but ATCC 10577 produced the highest biomass. Fungal biotransformation of crude glycerol into the commercially valuable organic acid malic acid appeared feasible.

  20. Biotransformation of (-)-a-pinene by Botrytis cinerea.

    PubMed

    Farooq, Afgan; Tahara, Satoshi; Choudhary, M Iqbal; Atta-ur-Rahman; Ahmed, Zafar; Hüsnü, Can Başer K; Demirci, Fatih

    2002-01-01

    (-)-alpha-Pinene (1), a major constituent of many aromatic plants was biotransformed by the plant pathogenic fungus, Botrytis cinerea to afford three new metabolites, characterized as 3beta-hydroxy-(-)-beta-pinene (10%) (3), 9-hydroxy-(-)-a-pinene (12%) (4), 4beta-hydroxy-(-)-alpha-pinene-6-one (16%) (5) by physical and spectroscopic methods. A known metabolite verbenone (2) was also obtained.

  1. Crosses between monokaryons of Pleurotus sapidus or Pleurotus florida show an improved biotransformation of (+)-valencene to (+)-nootkatone.

    PubMed

    Omarini, Alejandra B; Plagemann, Ina; Schimanski, Silke; Krings, Ulrich; Berger, Ralf G

    2014-11-01

    Several hundred monokaryotic and new dikaryotic strains derived thereof were established from (+)-valencene tolerant Pleurotus species. When grouped according to their growth rate on agar plates and compared to the parental of Pleurotus sapidus 69, the slowly growing monokaryons converted (+)-valencene more efficiently to the grapefruit flavour compound (+)-nootkatone. The fast growing monokaryons and the slow×slow and the fast×fast dikaryotic crosses showed similar or inferior yields. Some slow×fast dikaryons, however, exceeded the biotransformation capability of the parental dikaryon significantly. The activity of the responsible enzyme, lipoxygenase, showed a weak correlation with the yields of (+)-nootkatone indicating that the determination of enzyme activity using the primary substrate linoleic acid may be misleading in predicting the biotransformation efficiency. This exploratory study indicated that a classical genetics approach resulted in altered and partly improved terpene transformation capability (plus 60%) and lipoxygenase activity of the strains. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Evaluation of Diuron Tolerance and Biotransformation by Fungi from a Sugar Cane Plantation Sandy-Loam Soil.

    PubMed

    Perissini-Lopes, Bruna; Egea, Tássia Chiachio; Monteiro, Diego Alves; Vici, Ana Cláudia; Da Silva, Danilo Grünig Humberto; Lisboa, Daniela Correa de Oliveira; de Almeida, Eduardo Alves; Parsons, John Robert; Da Silva, Roberto; Gomes, Eleni

    2016-12-14

    Microorganisms capable of degrading herbicides are essential to minimize the amount of chemical compounds that may leach into other environments. This work aimed to study the potential of sandy-loam soil fungi to tolerate the herbicide Herburon (50% diuron) and to degrade the active ingredient diuron. Verticillium sp. F04, Trichoderma virens F28, and Cunninghamella elegans B06 showed the highest growth in the presence of the herbicide. The evaluation of biotransformation showed that Aspergillus brasiliensis G08, Aspergillus sp. G25, and Cunninghamella elegans B06 had the greatest potential to degrade diuron. Statistical analysis demonstrated that glucose positively influences the potential of the microorganism to degrade diuron, indicating a cometabolic process. Due to metabolites founded by diuron biotransformation, it is indicated that the fungi are relevant in reducing the herbicide concentration in runoff, minimizing the environmental impact on surrounding ecosystems.

  3. Biotransformation kinetics and sorption of cocaine and its metabolites and the factors influencing their estimation in wastewater.

    PubMed

    Plósz, Benedek Gy; Reid, Malcolm J; Borup, Morten; Langford, Katherine H; Thomas, Kevin V

    2013-05-01

    The quantitative analysis of human urinary metabolites as biomarkers in wastewater streams has been used to estimate the rates of illicit drug use in the wider community. The primary underlying assumption in such studies is that a sample of wastewater is equivalent to a cumulative sample of urine. Drug metabolism in humans is predominantly enzymatically mediated, but these processes are not exclusive to the human body, and are found to occur in the environment and the sewer network. Understanding what happens to drugs and their urinary metabolites in the sewer system between the point of excretion and sampling is particularly important since it is possible that in-sewer transformation may influence final biomarker concentration. The present study uses batch experiments to measure and assess the biotransformation processes of cocaine and its two major human metabolites, benzoylecgonine and ecgonine methyl ester. The activated sludge modelling framework for xenobiotic organic micro-pollutants (ASM-X) is used for model structure identification and calibration. Biotransformation was observed to follow pseudo first-order kinetics. The biodegradation kinetics of cocaine, benzoylecgonine and ecgonine methyl ester is not significantly affected by the availability of dissolved oxygen. Results obtained in this study show that omitting in-pipe biotransformation affects the accuracy of back-calculated cocaine use estimates. This varies markedly depending on the in-sewer hydraulic retention time, total biomass concentration and the relative concentration of each metabolite. However, back-calculated cocaine use estimates derived from wastewater concentrations of benzoylecgonine and ecgonine methyl ester do show very close agreement if ex-vivo biotransformation of these compounds is considered.

  4. Bioaccumulation, sublethal toxicity, and biotransformation of sediment-associated pentachlorophenol in Lumbriculus variegatus (Oligochaeta).

    PubMed

    Mäenpää, K; Sorsa, K; Lyytikäinen, M; Leppänen, M T; Kukkonen, J V K

    2008-01-01

    The xenobiotics accumulated in sediments represent a hazard to organisms. In order to study the toxic effects of xenobiotics in organisms, body residue has been proposed as a more relevant dose-metric than the environmental concentration of the chemical. In this study, the benthic oligochaetes Lumbriculus variegatus were exposed to sediment-spiked pentachlorophenol (PCP) in a chronic study at different exposure concentrations. The aim was to examine sublethal toxic effects in sediment-dwelling and sediment-ingesting organisms, and to link the effects with chemical body residues. Growth, reproduction, and egestion rate were used as sublethal endpoints. Bioaccumulation, sublethal toxic effects, and biotransformation of PCP were investigated by exposing organisms to both artificial and natural sediments with similar organic carbon content. Sediment characteristics were assumed to have an effect on toxicity since PCP retarded both growth and reproduction in L. variegatus in the artificial sediment. In natural sediment, growth, and reproduction was also reduced in control treatments, probably indicating poor nutritional quality. Most of the extracted chemicals in L. variegatus tissues were water-soluble metabolites, indicating that L. variegatus was capable of biotransforming PCP. The extractable parent PCP body residues (CBR(50)) for L. variegatus growth and reproduction were in agreement with the values estimated for respiratory uncouplers in the literature.

  5. Biotransformation of monoaromatic and chlorinated hydrocarbons at an aviation-gasoline spill site

    SciTech Connect

    Wilson, B.H.; Wilson, J.T.; Kampbell, D.H.; Bledsoe, B.E.; Armstrong, J.M.

    1991-01-01

    Loss of petroleum products from underground storage tanks, pipelines, and accidental spills are major sources of contamination of unsaturated soils, aquifer solids, and a shallow water table aquifer under the U.S. Coast Guard Air Station at Traverse City, MI, has acclimated to the aerobic and anaerobic transformation of monoaromatic hydrocarbons (BTX) released from an aviation gasoline spill. The aquifer also exhibits reductive dechlorination of a chlorinated solvent spill adjacent to the aviation gasoline spill. The groundwater is buffered near neutrality. The aviation gasoline plume is methanogenic and the aquifer contains enough iron minerals to support significant iron solubilization. Field evidence of both aerobic and anaerobic biotransformation of monoaromatics was confirmed by laboratory studies of aquifer material obtained from the site. In the laboratory studies, the removal of the monoaromatics in the anaerobic material was rapid and compared favorable with removal in the aerobic material. The kinetics of anaerobic removal of monoaromatics in the laboratory were similar to the kinetics at field scale in the aquifer. Biotransformation of the chlorinated solvents was not observed until late in the study, when daughter products from reductive dechlorination of the chlorinated solvents were identified by GC/MS.

  6. Illinois Agricultural Occupations: An Occupational Employment Study of Agricultural Service Industries.

    ERIC Educational Resources Information Center

    Illinois Univ., Urbana.

    In response to a need for additional data on agriculturally related employment, the Illinois State Board of Education funded a research project with two objectives: to collect additional agricultural employment data and to identify employment in agriculturally related industries in Illinois under the Standard Industrial Classification system. The…

  7. A Five-Year Study on the Employability of UKM Graduates

    ERIC Educational Resources Information Center

    Khoon, Koh Aik; Din, Laily; Ahmad, Shaharuddin; Hamzah, Mohd Fauzi; Samah, Fatin Nur Diana Abu

    2013-01-01

    This paper reports on the employability of UKM graduates for the past five years (2006-2010). The employability of our graduates has consistently improved through the years. Medical and dental cohorts have less problems finding gainful employment compared with cohorts from other disciplines. Since 2008, our graduates have made inroads into sectors…

  8. Labour Markets and Employment Practices in the Age of Flexibility: A Case Study of Silicon Valley.

    ERIC Educational Resources Information Center

    Carnoy, Martin; And Others

    1997-01-01

    Flexible employment has accounted for more than half of Silicon Valley's total employment growth in the past 10 years. Flexible employment has become a permanent strategy that may create insecurity for low-skilled workers; it also leads to a high turnover rate among highly skilled workers. (JOW)

  9. A Five-Year Study on the Employability of UKM Graduates

    ERIC Educational Resources Information Center

    Khoon, Koh Aik; Din, Laily; Ahmad, Shaharuddin; Hamzah, Mohd Fauzi; Samah, Fatin Nur Diana Abu

    2013-01-01

    This paper reports on the employability of UKM graduates for the past five years (2006-2010). The employability of our graduates has consistently improved through the years. Medical and dental cohorts have less problems finding gainful employment compared with cohorts from other disciplines. Since 2008, our graduates have made inroads into sectors…

  10. In Vitro Biotransformation of Two Human CYP3A Probe Substrates and Their Inhibition during Early Zebrafish Development

    PubMed Central

    Verbueken, Evy; Alsop, Derek; Saad, Moayad A.; Pype, Casper; Van Peer, Els M.; Casteleyn, Christophe R.; Van Ginneken, Chris J.; Wilson, Joanna; Van Cruchten, Steven J.

    2017-01-01

    At present, the zebrafish embryo is increasingly used as an alternative animal model to screen for developmental toxicity after exposure to xenobiotics. Since zebrafish embryos depend on their own drug-metabolizing capacity, knowledge of their intrinsic biotransformation is pivotal in order to correctly interpret the outcome of teratogenicity assays. Therefore, the aim of this in vitro study was to assess the activity of cytochrome P450 (CYP)—a group of drug-metabolizing enzymes—in microsomes from whole zebrafish embryos (ZEM) of 5, 24, 48, 72, 96 and 120 h post-fertilization (hpf) by means of a mammalian CYP substrate, i.e., benzyloxy-methyl-resorufin (BOMR). The same CYP activity assays were performed in adult zebrafish liver microsomes (ZLM) to serve as a reference for the embryos. In addition, activity assays with the human CYP3A4-specific Luciferin isopropyl acetal (Luciferin-IPA) as well as inhibition studies with ketoconazole and CYP3cide were carried out to identify CYP activity in ZLM. In the present study, biotransformation of BOMR was detected at 72 and 96 hpf; however, metabolite formation was low compared with ZLM. Furthermore, Luciferin-IPA was not metabolized by the zebrafish. In conclusion, the capacity of intrinsic biotransformation in zebrafish embryos appears to be lacking during a major part of organogenesis. PMID:28117738

  11. Biotransformations of terpenes by fungi from Amazonian citrus plants.

    PubMed

    Moreno Rueda, Maria Gabriela; Guerrini, Alessandra; Giovannini, Pier Paolo; Medici, Alessandro; Grandini, Alessandro; Sacchetti, Gianni; Pedrini, Paola

    2013-10-01

    The biotransformations of (RS)-linalool (1), (S)-citronellal (2), and sabinene (3) with fungi isolated from the epicarp of fruits of Citrus genus of the Amazonian forest (i.e., C. limon, C. aurantifolia, C. aurantium, and C. paradisiaca) are reported. The more active strains have been characterized, and they belong to the genus Penicillium and Fusarium. Different biotransformation products have been obtained depending on fungi and substrates. (RS)-Linalool (1) afforded the (E)- and (Z)-furanlinalool oxides (7 and 8, resp.; 39 and 37% yield, resp.) with Fusarium sp. (1D2), 6-methylhept-5-en-2-one (4; 49%) with F. fujikuroi, and 1-methyl-1-(4-methypentyl)oxiranemethanol (6; 42%) with F. concentricum. (S)-Citronellal (2) gave (S)-citronellol (12; 36-76%) and (S)-citronellic acid (11; 5-43%) with Fusarium species, while diastereoisomeric p-menthane-3,8-diols 13 and 14 (20 and 50% yield, resp.) were obtained as main products with Penicillium paxilli. Finally, both Fusarium species and P. paxilli biotransformed sabinene (3) to give mainly 4-terpineol (19; 23-56%), and (Z)- and (E)-sabinene hydrates (17 (3-21%) and 18 (11-17%), resp.).

  12. Biotransformations of monoterpenes by photoautotrophic micro-organisms.

    PubMed

    Balcerzak, L; Lipok, J; Strub, D; Lochyński, S

    2014-12-01

    Monoterpenes are widely used in food technology, cosmetic and pharmaceutical industries and as compounds of agricultural importance. It is known that compounds comprising this class can be transformed by a variety of organisms, namely by: bacteria, fungi, yeasts, plants or isolated enzymes. Biotransformations, as one of the most important tools of green chemistry, allow obtaining new products using whole cells of micro-organisms or isolated enzymes in mild reaction conditions. Therefore, biotransformations of monoterpenes, by different type of reaction such as: epoxidation, oxidation and stereoselective hydroxylation, resulted in the production of so desired, enantiomerically defined compounds that can be advised as natural seem to be interesting. Bearing in mind that such processes are carried out also by easy to maintain, photoautotrophic micro-organisms cultivated at large scale, this paper is focused on biotransformations of acyclic, monocyclic and bicyclic monoterpenes by freshwater or haliphylic cyanobacteria and microalgae on the way of mainly stereoselective hydroxylation. Moreover, aspects of potential industrial application of obtained products in medicine, perfume, cosmetics and food industry are discussed.

  13. Stereoselective biotransformation of ketamine in equine liver and lung microsomes

    PubMed Central

    Schmitz, A.; Portier, C. J.; Thormann, W.; Theurillat, R.; Mevissen, M.

    2010-01-01

    Stereoselectivity has to be considered for pharmacodynamic and pharmacokinetic features of ketamine. Stereoselective biotransformation of ketamine was investigated in equine microsomes in vitro. Concentration curves were constructed over time, and enzyme activity was determined for different substrate concentrations using equine liver and lung microsomes. The concentrations of R/S-ketamine and R/S-norketamine were determined by enantioselective capillary electrophoresis. A two-phase model based on Hill kinetics was used to analyze the biotransformation of R/S-ketamine into R/S-norketamine and, in a second step, into R/S-downstream metabolites. In liver and lung microsomes, levels of R-ketamine exceeded those of S-ketamine at all time points and S-norketamine exceeded R-norketamine at time points below the maximum concentration. In liver and lung microsomes, significant differences in the enzyme velocity (Vmax) were observed between Sand R-norketamine formation and between Vmax of S-norketamine formation when S-ketamine was compared to S-ketamine of the racemate. Our investigations in microsomal reactions in vitro suggest that stereoselective ketamine biotransformation in horses occurs in the liver and the lung with a slower elimination of S-ketamine in the presence of R-ketamine. Scaling of the in vitro parameters to liver and lung organ clearances provided an excellent fit with previously published in vivo data and confirmed a lung first-pass effect. PMID:19000264

  14. Biotransformation and bioconcentration of pyrene in Daphnia magna.

    PubMed

    Akkanen, Jarkko; Kukkonen, Jussi V K

    2003-06-19

    Water fleas (Daphnia magna) were exposed to [14C]pyrene in the presence and absence of piperonyl butoxide (PBO), a general cytochrome P450 (CYP) inhibitor, in organic carbon-free artificial freshwater (AFW, DOC<0.2 mg l(-1)) and in natural lake water (DOC=19.9 mg l(-1)) for 24 h. The bioconcentration of total radioactivity after 24 h exposure was 50% lower in the natural lake water, indicating decreased bioavailability of pyrene by the dissolved organic matter. However, the proportions of parent compound were only ca. 12 and 19% of the total body burden in daphnids exposed in AFW and natural lake water, respectively. Therefore, the tissue concentration of the parent pyrene was not significantly different in the daphnids exposed in the two different waters. Due to extensive biotransformation the bioconcentration factor (BCF) of parent pyrene was only 16 and 23% of the BCF calculated on the basis of total radioactivity in the daphnids in AFW and natural lake water, respectively. The proportion of parent pyrene was significantly higher (over 60%) in the daphnids exposed simultaneously to PBO, which indicates the involvement of CYP monooxygenases in the biotransformation. Furthermore, increasing PBO concentration decreased the accumulation of total radioactivity in AFW but not in the natural lake water. The data demonstrate capability and importance of CYP monooxygenases in biotransformation of polycyclic aromatic hydrocarbons in D. magna.

  15. Biotransformation and biomethylation of arsenic by Shewanella oneidensis MR-1.

    PubMed

    Wang, Juan; Wu, Mingyin; Lu, Gan; Si, Youbin

    2016-02-01

    The resistance of Shewanella oneidensis MR-1 to toxic arsenic was investigated by measuring the growth of the bacteria in the presence of As(III) and As(V) in different growth media. The bacteria were shown to biotransform arsenic through the partial methylation of inorganic arsenic into methylated metabolites. This biotransformation of inorganic arsenic by S. oneidensis MR-1 was affected by the methyl donor, the composition of the medium, and the presence of Fe(III). The relative content of methylated arsenic in the medium containing S-adenosyl methionine as the methyl donor was greater than that in the medium containing methylcobalamin. The biotransformation process driven by Fe-reducing bacteria, and occurred in combination with microbially mediated As-Fe reduction in the presence of Fe(III). The results demonstrate that S. oneidensis MR-1 methylates inorganic arsenic into less toxic organoarsenic compounds. This process has potential applications in the bioremediation of environmental arsenic, and the results provide new insights into the control of in situ arsenic pollution.

  16. Upset susceptibility study employing circuit analysis and digital simulation. [digital systems and electromagnetic interference

    NASA Technical Reports Server (NTRS)

    Carreno, V. A.

    1984-01-01

    An approach to predict the susceptibility of digital systems to signal disturbances is described. Electrical disturbances on a digital system's input and output lines can be induced by activities and conditions including static electricity, lightning discharge, electromagnetic interference (EMI), and electromagnetic pulsation (EMP). The electrical signal disturbances employed for the susceptibility study were limited to nondestructive levels, i.e., the system does not sustain partial or total physical damage and reset and/or reload brings the system to an operational status. The front-end transition from the electrical disturbances to the equivalent digital signals was accomplished by computer-aided circuit analysis. The super-sceptre (system for circuit evaluation of transient radiation effects) programs was used. Gate models were developed according to manufacturers' performance specifications and parameters resulting from construction processes characteristic of the technology. Digital simulation at the gate and functional level was employed to determine the impact of the abnormal signals on system performance and to study the propagation characteristics of these signals through the system architecture. Example results are included for an Intel 8080 processor configuration.

  17. Upset susceptibility study employing circuit analysis and digital simulation. [digital systems and electromagnetic interference

    NASA Technical Reports Server (NTRS)

    Carreno, V. A.

    1984-01-01

    An approach to predict the susceptibility of digital systems to signal disturbances is described. Electrical disturbances on a digital system's input and output lines can be induced by activities and conditions including static electricity, lightning discharge, electromagnetic interference (EMI), and electromagnetic pulsation (EMP). The electrical signal disturbances employed for the susceptibility study were limited to nondestructive levels, i.e., the system does not sustain partial or total physical damage and reset and/or reload brings the system to an operational status. The front-end transition from the electrical disturbances to the equivalent digital signals was accomplished by computer-aided circuit analysis. The super-sceptre (system for circuit evaluation of transient radiation effects) programs was used. Gate models were developed according to manufacturers' performance specifications and parameters resulting from construction processes characteristic of the technology. Digital simulation at the gate and functional level was employed to determine the impact of the abnormal signals on system performance and to study the propagation characteristics of these signals through the system architecture. Example results are included for an Intel 8080 processor configuration.

  18. A Study of Performance Measures and Subgroup Impacts in Three Welfare Employment Programs. Research Report Series RR-87-28.

    ERIC Educational Resources Information Center

    Friedlander, Daniel; Long, David

    This study (the first part of a two-part study) analyzed the effectiveness of three mandatory welfare employment programs in serving different segments of the Aid to Families with Dependent Children (AFDC) caseload. Data were collected in evaluations of welfare employment initiatives in San Diego, Baltimore, and several counties in Virginia.…

  19. Interviewing in Virtual Worlds: A Phenomenological Study Exploring the Success Factors of Job Applicants Utilizing Second Life to Gain Employment

    ERIC Educational Resources Information Center

    Koufoudakis-Whittington, Stefania

    2014-01-01

    This study explored the phenomenon of success factors of job applicants utilizing Second Life to gain employment. The study focused on identifying the perception of what qualified as a successful interview through the lived common experiences of 16 employment recruiters. The research problem was that a gap existed in scholarly research on…

  20. Interviewing in Virtual Worlds: A Phenomenological Study Exploring the Success Factors of Job Applicants Utilizing Second Life to Gain Employment

    ERIC Educational Resources Information Center

    Koufoudakis-Whittington, Stefania

    2014-01-01

    This study explored the phenomenon of success factors of job applicants utilizing Second Life to gain employment. The study focused on identifying the perception of what qualified as a successful interview through the lived common experiences of 16 employment recruiters. The research problem was that a gap existed in scholarly research on…