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Sample records for biotransformation studies employing

  1. Tannase-mediated biotransformation assisted separation and purification of theaflavin and epigallocatechin by high speed counter current chromatography and preparative high performance liquid chromatography: A comparative study.

    PubMed

    Xia, Guobin; Lin, Chunfang; Liu, Songbai

    2016-09-01

    A large scale isolation and purification of theaflavin (TF) and epigallocatechin (EGC) has been successfully developed by tannase-mediated biotransformation combining high-speed countercurrent chromatography. After tannase hydrolysis of a commercially available theaflavins extract (TE), the content of TF and EGC in tannase-mediated biotransformation product (TBP) achieved approximately 3 times enrichment. SEM studies revealed smooth tannase biotransformation and the possibility of recovery of the tannase. A single 1.5 hours' HSCCC separation for TF and EGC employing a two-phase solvent system could simultaneously produce 180.8 mg of 97.3% purity TF and 87.5 mg of 97.3% purity EGC. However, a preparative HPLC separation of maximum injection volume containing 120 mg TBP prepared 11.2 mg TF of 94.9% purity and 7.7 mg EGC of 89.9% purity. HSCCC separation demonstrated significant advantages over Prep HPLC in terms of sample loading size, separation time, environmental friendly solvent systems, and the production. PMID:27389804

  2. Tannase-mediated biotransformation assisted separation and purification of theaflavin and epigallocatechin by high speed counter current chromatography and preparative high performance liquid chromatography: A comparative study.

    PubMed

    Xia, Guobin; Lin, Chunfang; Liu, Songbai

    2016-09-01

    A large scale isolation and purification of theaflavin (TF) and epigallocatechin (EGC) has been successfully developed by tannase-mediated biotransformation combining high-speed countercurrent chromatography. After tannase hydrolysis of a commercially available theaflavins extract (TE), the content of TF and EGC in tannase-mediated biotransformation product (TBP) achieved approximately 3 times enrichment. SEM studies revealed smooth tannase biotransformation and the possibility of recovery of the tannase. A single 1.5 hours' HSCCC separation for TF and EGC employing a two-phase solvent system could simultaneously produce 180.8 mg of 97.3% purity TF and 87.5 mg of 97.3% purity EGC. However, a preparative HPLC separation of maximum injection volume containing 120 mg TBP prepared 11.2 mg TF of 94.9% purity and 7.7 mg EGC of 89.9% purity. HSCCC separation demonstrated significant advantages over Prep HPLC in terms of sample loading size, separation time, environmental friendly solvent systems, and the production.

  3. 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.

  4. Microbial biotransformation: a tool for drug designing (Review).

    PubMed

    Pervaiz, I; Ahmad, S; Madni, M A; Ahmad, H; Khaliq, F H

    2013-01-01

    For centuries microbial biotransformation has proved to be an imperative tool in alleviating the production of various chemicals used in food, pharmaceutical, agrochemical and other industries. In the field of phar- maceutical research and development, biotransformation studies have been extensively applied to investigate the metabolism of compounds (leads, lead candidates, etc.) using animal models. The microbial biotransfor- mation phenomenon is then commonly employed in comparing metabolic pathways of drugs and scaling up the metabolites of interest discovered in these animal models for further pharmacological and toxicological evaluation. Microorganisms can conveniently afford drugs difficult obtained via synthesis. The plethora of reported microbial biotransformations along with its added benefits has already invoked further research in bioconversion of novel and structurally complex drugs. This review alternatively discusses the prospect of microbial biotransformation studies as a significant element ameliorating drug discovery and design in terms of cost-effectiveness, environment protection and greater structural diversity as compared to animal models used to study metabolism. To explicate the microbial biotransformation paradigm in drug designing 3 main areas in this aspect have been analyzed: 1--lead expansion: obtaining pharmacologically improved metabo- lites from bioactive molecules; 2--biosynthesis of precursors/intermediates involved in the production of bioactive molecules; 3--resolution of racemic mixture to obtain enantiomers possessing different pharma- cological profiles.

  5. Microbial biotransformation: a tool for drug designing (Review).

    PubMed

    Pervaiz, I; Ahmad, S; Madni, M A; Ahmad, H; Khaliq, F H

    2013-01-01

    For centuries microbial biotransformation has proved to be an imperative tool in alleviating the production of various chemicals used in food, pharmaceutical, agrochemical and other industries. In the field of phar- maceutical research and development, biotransformation studies have been extensively applied to investigate the metabolism of compounds (leads, lead candidates, etc.) using animal models. The microbial biotransfor- mation phenomenon is then commonly employed in comparing metabolic pathways of drugs and scaling up the metabolites of interest discovered in these animal models for further pharmacological and toxicological evaluation. Microorganisms can conveniently afford drugs difficult obtained via synthesis. The plethora of reported microbial biotransformations along with its added benefits has already invoked further research in bioconversion of novel and structurally complex drugs. This review alternatively discusses the prospect of microbial biotransformation studies as a significant element ameliorating drug discovery and design in terms of cost-effectiveness, environment protection and greater structural diversity as compared to animal models used to study metabolism. To explicate the microbial biotransformation paradigm in drug designing 3 main areas in this aspect have been analyzed: 1--lead expansion: obtaining pharmacologically improved metabo- lites from bioactive molecules; 2--biosynthesis of precursors/intermediates involved in the production of bioactive molecules; 3--resolution of racemic mixture to obtain enantiomers possessing different pharma- cological profiles. PMID:25508645

  6. Microbial biotransformation: a tool for drug designing (Review).

    PubMed

    Pervaiz, I; Ahmad, S; Madni, M A; Ahmad, H; Khaliq, F H

    2013-01-01

    For centuries microbial biotransformation has proved to be an imperative tool in alleviating the production of various chemicals used in food, pharmaceutical, agrochemical and other industries. In the field of phar- maceutical research and development, biotransformation studies have been extensively applied to investigate the metabolism of compounds (leads, lead candidates, etc.) using animal models. The microbial biotransfor- mation phenomenon is then commonly employed in comparing metabolic pathways of drugs and scaling up the metabolites of interest discovered in these animal models for further pharmacological and toxicological evaluation. Microorganisms can conveniently afford drugs difficult obtained via synthesis. The plethora of reported microbial biotransformations along with its added benefits has already invoked further research in bioconversion of novel and structurally complex drugs. This review alternatively discusses the prospect of microbial biotransformation studies as a significant element ameliorating drug discovery and design in terms of cost-effectiveness, environment protection and greater structural diversity as compared to animal models used to study metabolism. To explicate the microbial biotransformation paradigm in drug designing 3 main areas in this aspect have been analyzed: 1--lead expansion: obtaining pharmacologically improved metabo- lites from bioactive molecules; 2--biosynthesis of precursors/intermediates involved in the production of bioactive molecules; 3--resolution of racemic mixture to obtain enantiomers possessing different pharma- cological profiles. PMID:25474866

  7. 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

  8. 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

  9. 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.

  10. 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.

  11. Quantification of biotransformation of chlorinated hydrocarbons in a biostimulation study: Added value via stable carbon isotope analysis

    NASA Astrophysics Data System (ADS)

    Hirschorn, Sarah K.; Grostern, Ariel; Lacrampe-Couloume, Georges; Edwards, Elizabeth A.; MacKinnon, Leah; Repta, Cory; Major, David W.; Sherwood Lollar, Barbara

    2007-12-01

    Stable carbon isotope analysis of chlorinated aliphatic compounds was performed at an in situ biostimulation pilot test area (PTA) at a site where 1,2-dichloroethane (1,2-DCA) and trichloroethene (TCE) were present in groundwater. Chlorinated products of TCE reductive dechlorination ( cis-dichloroethene (cDCE) and vinyl chloride (VC)) were present at concentrations of 17.5 to 126.4 μmol/L. Ethene, a potential degradation product of both 1,2-DCA dihaloelimination and TCE reductive dechlorination was also present in the PTA. Emulsified soybean oil and lactate were added as electron donors to stimulate anaerobic dechlorination in the PTA. Stable carbon isotope analysis provided evidence that dechlorination was occurring in the PTA during biostimulation, and a means of monitoring changes in dechlorination efficiency over the 183 day monitoring period. Stable carbon isotope analysis was also used to determine if ethene production in the PTA was due to dechlorination of TCE, 1,2-DCA, or both. Fractionation factors ( α) were determined in the laboratory during anaerobic biotransformation of 1,2-DCA via a dihaloelimination reaction in four separate enrichment cultures. These α values (as well as the previously published ranges of α for the dechlorination of TCE, cDCE and 1,2-DCA) were used, along with isotopic values measured during the pilot test, to derive quantitative estimates of biotransformation during the pilot test. Dechlorination was found to account for 10.7 to 35.9%, 21.9 to 74.9%, and 54.4 to 67.8% of 1,2-DCA, TCE and cDCE concentration loss respectively in the PTA. Stable carbon isotope analysis indicates that dechlorination of 1,2-DCA, TCE and cDCE were all significant processes during the pilot test, while ethene production during the pilot test was dominated by 1,2-DCA dihaloelimination. This study demonstrates how stable carbon isotope analysis can provide more conservative estimates of the extent of biotransformation than do conventional protocols. In

  12. Bench-scale column experiments to study the containment of Cr(VI) in confined aquifers by bio-transformation.

    PubMed

    Shashidhar, T; Philip, Ligy; Murty Bhallamudi, S

    2006-04-17

    Bench-scale soil column experiments were conducted to study the effectiveness of Cr(VI) containment in confined aquifers using in situ bio-transformation. Batch adsorption studies were carried out to estimate the adsorption capacities of two different soils for Cr(VI) and Cr(III). Bio-kinetic parameters were evaluated for the enriched microbial system. The inhibition constant, evaluated using Monod's inhibition model, was found to be 11.46 mg/L of Cr(VI). Transport studies indicated that it would not be possible to contain Cr(VI) by adsorption alone. Transport and bio-transformation studies indicated that the pore velocity and the initial bio-mass concentration significantly affect the containment process. In situ bio-remediation is effective in the case of silty aquifers. Cr(VI) concentration of 25 mg/L was effectively contained within 60 cm of a confined silty aquifer. Cr(VI) containment could be achieved in sandy aquifers when the pore velocity was very low and the initial augmented bio-mass was high. A bio-barrier of approximately one meter width would be able to contain Cr(VI) if the initial Cr(VI) concentration is as much as 25 mg/L.

  13. 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

  14. 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

  15. Silica ecosystem for synergistic biotransformation.

    PubMed

    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

  16. 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.

  17. 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. PMID:27434255

  18. 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.

  19. LC-MS metabolic study on quercetin and taxifolin galloyl esters using human hepatocytes as toxicity and biotransformation in vitro cell model.

    PubMed

    Vacek, Jan; Papoušková, Barbora; Vrba, Jiří; Zatloukalová, Martina; Křen, Vladimír; Ulrichová, Jitka

    2013-12-01

    Galloyl esters of quercetin and taxifolin have been recently prepared semisynthetically as part of work towards modifying the solubility and modulating the biological activity of these natural flavonoids. In this paper we focused on the liquid chromatography-mass spectrometry (LC-MS) profiling of metabolites of 3-O-galloylquercetin and 7-O-galloyltaxifolin using human hepatocytes as the in vitro cell model. A subtoxic concentration (50μM) was used for both compounds and the formation of metabolites was monitored for 2h in hepatocytes and cultivation medium separately. Using negative electrospray ionization-quadrupole time-of-flight mass spectrometry (ESI-QqTOF MS), we identified different biotransformation patterns for the studied compounds. 3-O-Galloylquercetin is metabolized directly to glucuronides and methyl derivatives. In contrast, 7-O-galloyltaxifolin is oxidized to 7-O-galloylquercetin or cleaved to taxifolin, and consequently the products formed are sulfated or glucuronidated. The oxidative biotransformation of 3-O-galloylquercetin and 7-O-galloyltaxifolin is also accompanied by ester bond cleavage presumably by cellular enzymes (esterases) in a nonspecific manner. Our results provide fundamental insights into the biotransformation of monogalloyl esters of flavonoids and can be applied in investigations of the pharmaceutical potential of other galloylated polyphenolic substances.

  20. 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

  1. 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.

  2. 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

  3. 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.

  4. Parallel biotransformation of tetrabromobisphenol A in Xenopus laevis and mammals: Xenopus as a model for endocrine perturbation studies.

    PubMed

    Fini, Jean-Baptiste; Riu, Anne; Debrauwer, Laurent; Hillenweck, Anne; Le Mével, Sébastien; Chevolleau, Sylvie; Boulahtouf, Abdelaye; Palmier, Karima; Balaguer, Patrick; Cravedi, Jean-Pierre; Demeneix, Barbara A; Zalko, Daniel

    2012-02-01

    The flame retardant tetrabromobisphenol A (TBBPA) is a high production flame retardant that interferes with thyroid hormone (TH) signaling. Despite its rapid metabolism in mammals, TBBPA is found in significant amounts in different tissues. Such findings highlight first a need to better understand the effects of TBBPA and its metabolites and second the need to develop models to address these questions experimentally. We used Xenopus laevis tadpoles to follow radiolabeled (14)C-TBBPA uptake and metabolism. Extensive and rapid uptake of radioactivity was observed, tadpoles metabolizing > 94% of (14)C-TBBPA within 8 h. Four metabolites were identified in water and tadpole extracts: TBBPA-glucuronide, TBBPA-glucuronide-sulfate, TBBPA-sulfate, and TBBPA-disulfate. These metabolites are identical to the TBBPA conjugates characterized in mammals, including humans. Most radioactivity (> 75%) was associated with sulfated conjugates. The antithyroid effects of TBBPA and the metabolites were compared using two in vivo measures: tadpole morphology and an in vivo tadpole TH reporter gene assay. Only TBBPA, and not the sulfated metabolites, disrupted thyroid signaling. Moreover, TBBPA treatment did not affect expression of phase II enzymes involved in TH metabolism, suggesting that the antithyroid effects of TBBPA are not due to indirect effects on TH metabolism. Finally, we show that only the parent TBBPA inhibits T3-induced transactivation in cells expressing human, zebrafish, or X. laevis TH receptor, TRα. We conclude, first, that perturbation of thyroid signaling by TBBPA is likely due to rapid direct action of the parent compound, and second, that Xenopus is an excellent vertebrate model for biotransformation studies, displaying homologous pathways to mammals. PMID:22086976

  5. 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,…

  6. 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.

  7. 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

  8. Comparative study of 17 β-estradiol on endocrine disruption and biotransformation in fingerlings and juveniles of Japanese sea bass Lateolabrax japonicus.

    PubMed

    Thilagam, Harikrishnan; Gopalakrishnan, Singaram; Bo, Jun; Wang, Ke-Jian

    2014-08-30

    Estrogenic contaminants in the aquatic environment are associated with endocrine disruption and feminization in fish. The effects of endocrine disrupting chemicals (EDCs) on fish have been well documented. However, very few studies have focused on 17 β-estradiol (E2) and its effects on endocrine system and biotransformation in a single prolonged exposure. This study investigated changes in the levels of serotonin (5-hydroxytryptamine) and acetyl choline esterase (AchE) in brain, cortisol in plasma and Ethoxyresorufin-O-deethylase (EROD) activity in gill of two different size groups (fingerlings and juveniles) of Japanese sea bass (Lateolabrax japonicus) upon exposure to two sub-lethal concentrations (200 and 2000 ng L(-1)) of E2 for 30 d. The results indicate that cortisol level and EROD activity significantly increased in both groups, whereas serotonin level increased in juveniles and decreased in fingerlings due to E2 exposure. The correlation analysis revealed that E2 significantly affected the endocrine and biotransformation systems in both age groups. PMID:24882444

  9. Comparative study of 17 β-estradiol on endocrine disruption and biotransformation in fingerlings and juveniles of Japanese sea bass Lateolabrax japonicus.

    PubMed

    Thilagam, Harikrishnan; Gopalakrishnan, Singaram; Bo, Jun; Wang, Ke-Jian

    2014-08-30

    Estrogenic contaminants in the aquatic environment are associated with endocrine disruption and feminization in fish. The effects of endocrine disrupting chemicals (EDCs) on fish have been well documented. However, very few studies have focused on 17 β-estradiol (E2) and its effects on endocrine system and biotransformation in a single prolonged exposure. This study investigated changes in the levels of serotonin (5-hydroxytryptamine) and acetyl choline esterase (AchE) in brain, cortisol in plasma and Ethoxyresorufin-O-deethylase (EROD) activity in gill of two different size groups (fingerlings and juveniles) of Japanese sea bass (Lateolabrax japonicus) upon exposure to two sub-lethal concentrations (200 and 2000 ng L(-1)) of E2 for 30 d. The results indicate that cortisol level and EROD activity significantly increased in both groups, whereas serotonin level increased in juveniles and decreased in fingerlings due to E2 exposure. The correlation analysis revealed that E2 significantly affected the endocrine and biotransformation systems in both age groups.

  10. 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.

  11. Pyrene biotransformation products as biomarkers of polycyclic aromatic hydrocarbon exposure in terrestrial Isopoda: concentration-response relationship, and field study in a contaminated forest.

    PubMed

    Stroomberg, Gerard J; Ariese, Freek; van Gestel, Cornelis A M; van Hattum, Bert; Velthorst, Nel H; van Straalen, Nico M

    2003-01-01

    In this study, biotransformation products of pyrene were measured in the hepatopancreas of terrestrial isopods as biomarkers of polycyclic aromatic hydrocarbon (PAH) exposure. These products--pyrene-1-glucoside, pyrene-1-sulfate, an unknown pyrene conjugate, and 1-hydroxypyrene--were quantitated using high-performance liquid chromatography (HPLC) with fluorescence detection. In a controlled exposure experiment, a linear relationship was established between pyrene exposure and pyrene metabolite concentrations in the hepatopancreas of Porcellio scaber Latr. To this end, isopods of the species P. scaber were exposed to a range of pyrene concentrations spiked to their food. A linear response was found for all pyrene conjugates in the range 0.67 to 67 microg/g of pyrene (dry wt). Hepatopancreatic pyrene metabolite concentrations were also measured in isopods (P. scaber and Oniscus asellus L.) from PAH-contaminated field sites. The sites and the inhabiting isopods were located in a gradient of atmospheric PAH deposition caused by a nearby blast furnace plant. The highest levels of conjugated 1-hydroxypyrene in the hepatopancreas were 3.8 pmol/g fresh weight (pyrene-1-glucoside) and 2.8 pmol/g fresh weight (pyrene-1-sulfate) (expressed on whole-body basis). The levels of the pyrene metabolites correlate with reported pyrene concentrations in spite of these sites. As pyrene is one of the most predominant PAHs, analysis of its metabolites provides a good tool for environmental risk assessment of ecosystems with regard to PAH exposure, bioavailability, and biotransformation.

  12. 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.

  13. Biotransformation of Meloxicam by Cunninghamella blakesleeana: Significance of Carbon and Nitrogen Source.

    PubMed

    Shyam Prasad, Gurram; Narasimha Rao, Kollu; Preethi, Rama; Girisham, Sivasri; Reddy, S M

    2011-01-01

    Influence of carbon and nitrogen source, on biotransformation of meloxicam was studied by employing Cunninghamella blakesleeana NCIM 687 with an aim to achieve maximum transformation of meloxicam and in search of new metabolites. The transformation was confirmed by HPLC and based on LC-MS-MS data and previous reports the metabolites were predicted as 5-hydroxymethyl meloxicam, 5-carboxy meloxicam and a novel metabolite. The quantification of metabolites was performed using HPLC peak areas. The results obtained indicate that glucose as carbon source, ammonium nitrate as nitrogen source, were found to be optimum for maximum transformation of meloxicam. The study suggests the significance of these factors in biotransformation of meloxicam using microbial cultures. The fermentation was scaled up to 1 l level. PMID:22282633

  14. Employability.

    ERIC Educational Resources Information Center

    Texas Tech Univ., Lubbock. Home Economics Curriculum Center.

    This workbook contains seven units designed to help secondary-level vocational education students develop the employability skills necessary to find, keep, and advance in a job. Addressed in the individual units of the workbook are the following topics: assessing individual values, abilities, and interests; finding a job; developing basic…

  15. 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. PMID:26479917

  16. 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.

  17. Biodegradation and biotransformation of explosives.

    PubMed

    Rylott, Elizabeth L; Lorenz, Astrid; Bruce, Neil C

    2011-06-01

    Explosives now contaminate millions of hectares of land in the US alone, with global levels of contamination difficult to fully assess. Understanding the biology behind the metabolism of these toxic compounds by microorganisms and plants is imperative for managing these pollutants in the environment. Towards this aim, recent studies have identified, and are now characterizing, plant genes involved in 2,4,6-trinitrotoluene detoxification and the biochemical pathways of nitramine degradation in microorganisms. A key scientific goal continues to be identification of enzymes capable of degrading 2,4,6-trinitrotoluene and this still remains elusive, although recent reports give insights into the origin of nitrite released during biotransformation of this major contaminant. Promising phytoremediation research using transgenic model plant systems has now been transferred to poplar, a species with field applicability. PMID:21094036

  18. Effects of antibacterial agents on in vitro ovine ruminal biotransformation of the hepatotoxic pyrrolizidine alkaloid jacobine.

    PubMed

    Wachenheim, D E; Blythe, L L; Craig, A M

    1992-08-01

    Ingestion of pyrrolizidine alkaloids, naturally occurring plant toxins, causes illness and death in a number of animal species. Senecio jacobaea pyrrolizidine alkaloids cause significant economic losses due to livestock poisoning, particularly in the Pacific Northwest. Some sheep are resistant to pyrrolizidine alkaloid poisoning, because ovine ruminal biotransformation detoxifies free pyrrolizidine alkaloids in digesta. Antibacterial agents modify ruminal fermentation. Pretreatment with antibacterial agents may account for some animal variability in resistance to pyrrolizidine alkaloid toxicosis, and antibacterial agents can also be used for characterizing ruminal pyrrolizidine alkaloid-biotransforming microflora. The objective of this study was to evaluate the effects of antibacterial agents on biotransformation of a predominant S. jacobaea pyrrolizidine alkaloid, jacobine, in ovine ruminal contents. Ovine ruminal jacobine biotransformation was tested in vitro with 20 independent antibacterial agents. Low amounts of rifampin and erythromycin prevented jacobine biotransformation. Chlortetracycline, lasalocid, monensin, penicillin G, and tetracycline were slightly less effective at inhibiting jacobine biotransformation. Bacitracin, crystal violet, kanamycin, and neomycin were moderately inhibitory against jacobine biotransformation. Brilliant green, chloramphenicol, gramicidin, nalidixic acid, polymyxin B SO4, sodium azide, streptomycin, sulfisoxazole, and vancomycin had little to no effect on jacobine biotransformation. The antibiotics that were most effective at inhibiting biotransformation were those that are active against gram-positive bacteria. Therefore, gram-positive bacteria are most likely critical members of the jacobine-biotransforming consortia.

  19. Physics Manpower, 1973, Education and Employment Studies.

    ERIC Educational Resources Information Center

    American Inst. of Physics, New York, NY.

    Discussed in this document are the changes within the physics profession, their causes and effect. Detailed statistical data are supplied concerning physics enrollments, the institutions where physics is taught, the faculty in physics departments, and the nonacademic employment of physicists. Other topics include employment, education, minority…

  20. Biotransformation and Rearrangement of Laromustine.

    PubMed

    Nassar, Alaa-Eldin F; Wisnewski, Adam V; King, Ivan

    2016-08-01

    This review highlights the recent research into the biotransformations and rearrangement of the sulfonylhydrazine-alkylating agent laromustine. Incubation of [(14)C]laromustine with rat, dog, monkey, and human liver microsomes produced eight radioactive components (C-1 to C-8). There was little difference in the metabolite profile among the species examined, partly because NADPH was not required for the formation of most components, which instead involved decomposition and/or hydrolysis. The exception was C-7, a hydroxylated metabolite, largely formed by CYP2B6 and CYP3A4/5. Liquid chromatography-multistage mass spectrometry (LC-MS(n)) studies determined that collision-induced dissociation, and not biotransformation or enzyme catalysis, produced the unique mass spectral rearrangement. Accurate mass measurements performed with a Fourier-transform ion cyclotron resonance mass spectrometer (FTICR-MS) significantly aided determination of the elemental compositions of the fragments and in the case of laromustine revealed the possibility of rearrangement. Further, collision-induced dissociation produced the loss of nitrogen (N2) and methylsulfonyl and methyl isocyanate moieties. The rearrangement, metabolite/decomposition products, and conjugation reactions were analyzed utilizing hydrogen-deuterium exchange, exact mass, (13)C-labeled laromustine, nuclear magnetic resonance spectroscopy (NMR), and LC-MS(n) experiments to assist with the assignments of these fragments and possible mechanistic rearrangement. Such techniques produced valuable insights into these functions: 1) Cytochrome P450 is involved in C-7 formation but plays little or no role in the conversion of [(14)C]laromustine to C-1 through C-6 and C-8; 2) the relative abundance of individual degradation/metabolite products was not species-dependent; and 3) laromustine produces several reactive intermediates that may produce the toxicities seen in the clinical trials. PMID:27278961

  1. The California Study on Women in Nontraditional Employment.

    ERIC Educational Resources Information Center

    Advocates for Women, San Francisco, CA.

    In order to identify the barriers currently excluding women from equal access to non-traditional employment, a study examined ten agencies and programs in California which provide employment services to women. They may be categorized as either women's agencies, Comprehensive Employment Training Act (CETA) subcontractors (employment services),…

  2. 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.

  3. Production of anti-cancer agent using microbial biotransformation.

    PubMed

    Roh, Changhyun; Kang, ChanKyu

    2014-01-01

    Microbial biotransformation is a great model system to produce drugs and biologically active compounds. In this study, we elucidated the fermentation and production of an anti-cancer agent from a microbial process for regiospecific hydroxylation of resveratrol. Among the strains examined, a potent strain showed high regiospecific hydroxylation activity to produce piceatannol. In a 5 L (w/v 3 L) jar fermentation, this wild type Streptomyces sp. in the batch system produced 205 mg of piceatannol (i.e., 60% yields) from 342 mg of resveratrol in 20 h. Using the product, an in vitro anti-cancer study was performed against a human cancer cell line (HeLa). It showed that the biotransformed piceatannol possessed a significant anticancer activity. This result demonstrates that a biotransformation screening method might be of therapeutic interest with respect to the identification of anti-cancer drugs. PMID:25325153

  4. 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.

  5. Nitroreductase catalyzed biotransformation of CL-20.

    PubMed

    Bhushan, Bharat; Halasz, Annamaria; Hawari, Jalal

    2004-09-10

    Previously, we reported that a salicylate 1-monooxygenase from Pseudomonas sp. ATCC 29352 biotransformed CL-20 (2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaaza-isowurtzitane) (C(6)H(6)N(12)O(12)) and produced a key metabolite with mol. wt. 346 Da corresponding to an empirical formula of C(6)H(6)N(10)O(8) which spontaneously decomposed in aqueous medium to produce N(2)O, NH(4)(+), and HCOOH [Appl. Environ. Microbiol. (2004)]. In the present study, we found that nitroreductase from Escherichia coli catalyzed a one-electron transfer to CL-20 to form a radical anion (CL-20(-)) which upon initial N-denitration also produced metabolite C(6)H(6)N(10)O(8). The latter was tentatively identified as 1,4,5,8-tetranitro-1,3a,4,4a,5,7a,8,8a-octahydro-diimidazo[4,5-b:4',5'-e]pyrazine [IUPAC] which decomposed spontaneously in water to produce glyoxal (OHCCHO) and formic acid (HCOOH). The rates of CL-20 biotransformation under anaerobic and aerobic conditions were 3.4+/-0.2 and 0.25+/-0.01 nmol min(-1)mg of protein(-1), respectively. The product stoichiometry showed that each reacted CL-20 molecule produced about 1.8 nitrite ions, 3.3 molecules of nitrous oxide, 1.6 molecules of formic acid, 1.0 molecule of glyoxal, and 1.3 ammonium ions. Carbon and nitrogen products gave mass-balances of 60% and 81%, respectively. A comparative study between native-, deflavo-, and reconstituted-nitroreductase showed that FMN-site was possibly involved in the biotransformation of CL-20. PMID:15313201

  6. 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)

  7. 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…

  8. 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

  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. Study of Employment of Women in the Federal Government 1971.

    ERIC Educational Resources Information Center

    Civil Service Commission, Washington, DC. Manpower Statistics Div.

    This study presents statistical information gained from a survey of women employed full-time in Federal civilian collar employment as of October 31, 1971 in the Washington, D.C., metropolitan area, the 50 states and the territories of the U.S., and foreign countries. Excluded from the survey are members and employees of the Congress, employees of…

  11. 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.)

  12. A Study of Illinois Employer Reactions to Training Credentials.

    ERIC Educational Resources Information Center

    Adams, Frank G.; And Others

    A study was conducted in summer 1982 by Project REA to provide employment skill training operators and educators in Illinois with information about the reactions, attitudes, and beliefs of employers toward various forms of accreditation of training, i.e., academic credit, nonacademic credit, certificates, degrees, diplomas, and licenses. The study…

  13. 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.

  14. 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...

  15. The ICD Survey II: Employing Disabled Americans. A Nationwide Survey of 920 Employers. Study No. 864009.

    ERIC Educational Resources Information Center

    National Council on the Handicapped, Washington, DC.

    A survey explored what 921 managers nationwide are doing to employ disabled people and return disabled employees to work. It identified barriers that prevent employers from hiring disabled people and steps public and private sectors could take to increase their employment. Employers gave their disabled employees high marks as hard working,…

  16. 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...

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

    PubMed

    Men, Yujie; Han, Ping; Helbling, Damian E; Jehmlich, Nico; Herbold, Craig; Gulde, Rebekka; Onnis-Hayden, Annalisa; Gu, April Z; Johnson, David R; Wagner, Michael; Fenner, Kathrin

    2016-05-01

    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

  18. 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

  19. Chemical synthesis and hepatic biotransformation of 3 alpha,7 alpha-dihydroxy-7 beta-methyl-24-nor-5 beta-cholan-23-oic acid, a 7-methyl derivative of norchenodeoxycholic acid: studies in the hamster.

    PubMed

    Yoshii, M; Mosbach, E H; Schteingart, C D; Hagey, L R; Hofmann, A F; Cohen, B I; McSherry, C K

    1991-11-01

    A new bile acid analogue, 3 alpha,7 alpha-dihydroxy-7 beta-methyl-24-nor-5 beta-cholan-23-oic acid (7-Me-norCDCA) was synthesized from the methyl ester of norursodeoxycholic acid, and its hepatic biotransformation was defined in the hamster. To synthesize 7-Me-norCDCA, the 3 alpha-hydroxyl group of methyl norursodeoxycholate was protected as the hemisuccinate, and the 7 beta-hydroxyl group was oxidized with CrO3 to form the 7-ketone. A Grigard reaction with methyl magnesium iodide followed by alkaline hydrolysis gave 7-Me-norCDCA (greater than 70% yield). The structure of the new compound was confirmed by proton magnetic resonance and mass spectrometry. After intraduodenal administration of the 14C-labeled compound into the anesthetized biliary fistula hamster, it was rapidly and efficiently secreted into the bile; 80% of radioactivity was recovered in 2 h. After intravenous infusion, the compound was efficiently extracted by the liver and secreted into the bile (greater than 75% in 3 h). Most (93%) of the biliary radioactivity was present in biotransformation products. The major biotransformation product (48.7 +/- 6.0%) was a new compound, assigned the structure of 3 alpha,5 beta,7 alpha- trihydroxy-7 beta-methyl-24-nor-5 beta-cholan-23-oic acid (5 beta-hydroxy-7- Me-norCDCA). In addition, conjugates of 7-Me-norCDCA with taurine (13.7 +/- 5.0%), sulfate (10.3 +/- 3.0%), or glucuronide (5.1 +/- 1.7%) were formed. 7-Me-norCDCA was strongly choleretic in the hamster; during its intravenous infusion, bile flow increased 2 to 3 times above the basal level, and the calculated choleretic activity of the compound (and its metabolic products) was much greater than that of many natural bile acids, indicating that the compound induced hypercholeresis. It is concluded that the biotransformation and physiological properties of 7-Me-norCDCA closely resemble those of norCDCA. Based on previous studies, the major biological effect of the 7-methyl group in 7-Me-norCDCA is to

  20. 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…

  1. Role of SULT-mediated sulfation in the biotransformation of 2-butoxyethanol and sorbitan monolaurate: A study using zebrafish SULTs.

    PubMed

    Xi, Yuecheng; Seyoum, Helen; Liu, Ming-Cheh

    2016-08-01

    2-Butoxyethanol and sorbitan monolaurate are major components of oil dispersants that are applied in large quantities to control oil spill in the aquatic environment. An important question is whether aquatic animals are equipped with mechanisms for the detoxification of these oil dispersant compounds. The current study aimed to examine whether zebrafish cytosolic sulfotransferases (SULTs) are capable of sulfating 2-butoxyethanol and sorbitan monolaurate. A systematic analysis of 18 zebrafish SULTs revealed that SULT3 ST1 showed the strongest sulfating activity toward 2-butoxyethanol, while SULT1 ST3 displayed the strongest sulfating activity toward sorbitan monolaurate. The pH-dependence of these two SULTs in mediating the sulfation of 2-butoxyethanol or sorbitan monolaurate was examined. Taken together, these results implied that SULT-mediated sulfation may function in the detoxification of these two oil dispersant compounds. PMID:27218426

  2. Studies on the Biotransformation of Veratric Acid, a Human Metabolite of Mebeverine, by Using the Incubated Hen's Egg.

    PubMed

    Kiep, L; Göhl, M; Schmidt, J; Seifert, K

    2015-09-01

    Metabolism studies with selected test substances have shown that a model on the basis of the incubated hen's egg is suitable as a supplement to animal experimentation. Because of its 3,4-dimethoxyphenyl structure veratric acid (3,4-dimethoxybenzoic acid), a known human metabolite of mebeverine, was chosen as model substance for the present investigations and the parent compound as well as 4-hydroxy-3-methoxybenzoic acid were identified as main metabolites. The absence of 3-hydroxy-4-methoxybenzoic acid lets conclude that the O-demethylation takes place exclusively at the p-methoxyl function. In addition, 3,3',4,4'-tetramethoxy-l-ornithuric acid (2,5-bis-(3,4-dimethoxybenzoylamino)pentanoic acid) and its O-desmethyl derivative could be characterized as further metabolites. So far an amino acid conjugate has not been described after veratric acid administration in a vertebrate. There were no indications for the appearance of 3,4-dihydroxybenzoic acid in the veratric acid metabolism. This was confirmed by corresponding studies having the isomeric guaiacol acids as precursor. Furthermore, it could be proved that in ovo the O-methylation of 3,4-dihydroxybenzoic acid occurs regioselective at the m-hydroxyl group. The results which broaden the knowledge on the metabolic fate of veratric acid are discussed in comparison with those in mammals. The metabolites were identified by GC-MS, ESI-HRMS and LC/ESI-MS/MS. The structure of the synthesized reference substance was confirmed by MS, (1)H and (13)C NMR spectral data. PMID:25310250

  3. 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.

  4. 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...

  5. 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, ...

  6. New Technology and Women's Employment. Case Studies from West Yorkshire.

    ERIC Educational Resources Information Center

    Huws, Ursula

    A study examined the impact of new technology upon women's employment in West Yorkshire in Great Britain. During the study, 2,000 copies of a questionnaire were distributed to past and present users of the Leeds Trade Union and Community Resource and Information Centre (TUCRIC) as well as to participants at a conference entitled Women and New…

  7. 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

  8. Illness and the workplace: a study of physicians and employers.

    PubMed

    Merrill, R N; Pransky, G; Hathaway, J; Scott, D

    1990-07-01

    Seven million patients with work-related injuries are seen annually in the United States, the majority by primary care physicians. The number of such patients seen in a typical community practice may be significant but has never been studied. Most community-based physicians have little or no formal training in occupational health care. This study consisted of a survey of practicing physicians and major industrial employers in a city of 39,000 with a strong manufacturing base. The purpose was to assess physician skills, attitudes, and practices that might influence the optimal management of patients with work-related conditions, and to assess employer attitudes about this management. Eighty-three percent of physicians and 68% of employers responded to the written surveys. Low numbers of patients with work-related conditions were reported except by orthopedists and a neurologist. Few physicians communicated directly with employers, citing time and confidentiality as factors. Twenty-five percent were unaware of specific legal guidelines for such contact. Administrative and legal complexities were cited by 97% of the respondents as barriers to effective management of such cases. Eight percent of employers sought more contact with physicians, including site visits and more detailed work restriction guidelines. The education of primary care physicians may improve their understanding of work-related conditions and the optimal management and rehabilitation of these patients. PMID:2362176

  9. Biotransformation of nitric oxide

    SciTech Connect

    Yoshida, K.; Kasama, K.

    1987-08-01

    Previous investigations into the health effects of nitrogen oxides (NO/sub x/) have mostly been conducted with special reference to nitrogen dioxide (NO/sub 2/) and its direct effects on the respiratory system, while the study of nitric oxide (NO) has been disregarded. The authors carried out a study on NO by exposing rats and mice to /sup 15/NO or administering /sup 15/N-nitrite and /sup 15/N-nitrate to these animals by IP injection in order to elucidate the metabolic fate of NO. The results of their study and previous findings led them to assume that the major metabolic path of inhaled NO is as follows: inhaled NO reacts with hemoglobin, forming nitrosyl-hemoglobin (NOHb), and from NOHb, nitrate (NO/sub 2//sup -/ and nitrate (NO/sub 3//sup -/) are generated. Major quantities of NO/sub 3//sup -/ are discharged into the urine and a certain amount is discharged into the oral cavity through the salivary glands and transformed to NO/sub 2//sup -/. Part of this NO/sub 2//sup -/ is converted to N/sub 2/ gas in the stomach. Nitrate in the intestine is partly reduced to ammonia (NH/sub 3/) through NO/sub 2//sup -/, reabsorbed into the body, and converted to urea. Most of the metabolites of inhaled NO are excreted rapidly from the body within 48 hr.

  10. 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. PMID:27284203

  11. Mulberry anthocyanin biotransformation by intestinal probiotics.

    PubMed

    Cheng, Jing-Rong; Liu, Xue-Ming; Chen, Zhi-Yi; Zhang, You-Sheng; Zhang, Ye-Hui

    2016-12-15

    This study was designed to evaluate mulberry anthocyanins bioconversion traits for intestinal probiotics. Five intestinal beneficial bacteria were incubated with mulberry anthocyanins under anaerobic conditions at 37°C, and bacterial β-glucosidase activity and anthocyanin level were determined. Results demonstrated that all strains could convert mulberry anthocyanins to some extent. With high β-glucosidase production capacity, Streptococcus thermophiles GIM 1.321 and Lactobacillus plantarum GIM 1.35 degraded mulberry anthocyanins by 46.17% and 43.62%, respectively. Mulberry anthocyanins were mainly biotransformed to chlorogenic acid, crypto-chlorogenic acid, caffeic acid, and ferulic acid during the anaerobic process. Non-enzymatic deglycosylation of anthocyanins also occurred and approximately 19.42% of the anthocyanins were degraded within 48h by this method. PMID:27451240

  12. The chemistry and biotransformation of tea constituents.

    PubMed

    Sang, Shengmin; Lambert, Joshua D; Ho, Chi-Tang; Yang, Chung S

    2011-08-01

    Tea (Camellia sinensis, Theaceae) is one of the most widely consumed beverages in the world. The three major types of tea, green tea, oolong tea, and black tea, differ in terms of the manufacture and chemical composition. There are numerous studies in humans, animal models, and cell lines to suggest potential health benefits from the consumption of tea, including prevention of cancer and heart diseases. Many of the health benefits have been attributed to the polyphenolic constituents in tea. Catechins and their dimers (theaflavins) and polymers (thearubigins) have been identified as the major components in tea. Methylation, glucuronidation, sulfation, and ring-fission metabolism represent the major metabolic pathways for tea catechins. The present review summarizes the data concerning the chemistry and biotransformation of tea constituents. PMID:21371557

  13. Bisphenol A--sources, toxicity and biotransformation.

    PubMed

    Michałowicz, Jaromir

    2014-03-01

    Bisphenol A (BPA) is a chemical compound used in massive amounts in the production of synthetic polymers and thermal paper. In this review, the sources of BPA, which influence its occurrence in the environment and human surrounding will be presented. Data concerning BPA occurrence in food, water and indoor environments as well as its appearance in tissues and body fluids of human body will be shown. The results of in vitro and in vivo studies and the results of epidemiological surveys showing toxic, endocrine, mutagenic and cancerogenic action of BPA will also be discussed. Moreover, data suggesting that exposure of human to BPA may elevate risk of obesity, diabetes and coronary heart diseases will be presented. Finally, biotransformation of BPA in animals, plants and microorganisms (bacteria, fungi, algae), resulting in the formation of various metabolites that exhibit different from BPA toxicity will be described.

  14. 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…

  15. 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.…

  16. 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…

  17. An employer's experience with infertility coverage: a case study.

    PubMed

    Silverberg, Kaylen; Meletiche, Dennis; Del Rosario, Gina

    2009-12-01

    A case study of Southwest Airlines, a Fortune 500 company, demonstrates that a well-designed infertility coverage plan can control resource use. This successful model could be used by employers who wish to ensure that their employees have access to high-quality, cost-effective infertility services in a managed-care environment. PMID:19631318

  18. Fungal biotransformation of ezetimibe

    PubMed Central

    Pervaiz, Irfan; Ahmad, Saeed; Khaliq, Farhan Hameed; Arshad, Adeel; Imran, Muhammad; Khan, Barkat Ali; Ullah, Aftab; Ali, Usman; Iqbal, Kashif; Usman, Muhammad; Bibi, Hafsa; Khan, Najm Ul Hassan; Mahmood, Wajahat

    2014-01-01

    Structural transformation of ezetimibe was performed by fungi Beauvaria bassiana and Cunninghamella blakesleeana. The metabolites were identified by different spectroscopic techniques as (3R,4S)-1-(4-fluorophenyl)-3-((E)-3-(4-fluorophenyl) allyl)-4-(4-hydroxyphenyl) azetidin-2-one (2), (3R, 4S)-1-(4-fluorophenyl)-3-(3-(4fluorophenyl)-3-oxopropyl)-4-(4-hydroxyphenyl) azetidin-2-one (3), (3R,4S) 1-(4-fluorophenyl)-3-(3-(4-fluorophenyl) propyl)-4-(4-hydroxyphenyl) azetidin-2-one (4) and (2R,5S)-N, 5-bis (4-fluorophenyl)-5-hydroxy-2-(4-hydroxybenzyl) pentanamide (5). This study displays two important features of these fungi, viz., their ability to metabolize halogenated compounds, and their capacity to metabolize drugs that are targets of the UDP-Glucuronyl Transferase System, a phenomenon not commonly observed. PMID:26019581

  19. 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

  20. 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.

  1. 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.

  2. How Biotransformation Influences Toxicokinetics of Azole Fungicides in the Aquatic Invertebrate Gammarus pulex.

    PubMed

    Rösch, Andrea; Anliker, Sabine; Hollender, Juliane

    2016-07-01

    Biotransformation is a key process that can greatly influence the bioaccumulation potential and toxicity of organic compounds. In this study, biotransformation of seven frequently used azole fungicides (triazoles: cyproconazole, epoxiconazole, fluconazole, propiconazole, tebuconazole and imidazoles: ketoconazole, prochloraz) was investigated in the aquatic invertebrate Gammarus pulex in a 24 h exposure experiment. Additionally, temporal trends of the whole body internal concentrations of epoxiconazole, prochloraz, and their respective biotransformation products (BTPs) were studied to gain insight into toxicokinetic processes such as uptake, elimination and biotransformation. By the use of high resolution tandem mass spectrometry in total 37 BTPs were identified. Between one (ketoconazole) and six (epoxiconazole) BTPs were identified per parent compound except for prochloraz, which showed extensive biotransformation reactions with 18 BTPs detected that were mainly formed through ring cleavage or ring loss. In general, most BTPs were formed by oxidation and conjugation reactions. Ring loss or ring cleavage was only observed for the imidazoles as expected from the general mechanism of oxidative ring openings of imidazoles, likely affecting the bioactivity of these BTPs. Overall, internal concentrations of BTPs were up to 3 orders of magnitude lower than that of the corresponding parent compound. Thus, biotransformation did not dominate toxicokinetics and only played a minor role in elimination of the respective parent compound, with the exception of prochloraz. PMID:27232586

  3. 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.

  4. 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.

  5. 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.

  6. 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…

  7. Biotransformation of tetracycline by a novel bacterial strain Stenotrophomonas maltophilia DT1.

    PubMed

    Leng, Yifei; Bao, Jianguo; Chang, Gaofeng; Zheng, Han; Li, Xingxing; Du, Jiangkun; Snow, Daniel; Li, Xu

    2016-11-15

    Although several abiotic processes have been reported that can transform antibiotics, little is known about whether and how microbiological processes may degrade antibiotics in the environment. This work isolated one tetracycline degrading bacterial strain, Stenotrophomonas maltophilia strain DT1, and characterized the biotransformation of tetracycline by DT1 under various environmental conditions. The biotransformation rate was the highest when the initial pH was 9 and the reaction temperature was at 30°C, and can be described using the Michaelis-Menten model under different initial tetracycline concentrations. When additional substrate was present, the substrate that caused increased biomass resulted in a decreased biotransformation rate of tetracycline. According to disk diffusion tests, the biotransformation products of tetracycline had lower antibiotic potency than the parent compound. Six possible biotransformation products were identified, and a potential biotransformation pathway was proposed that included sequential removal of N-methyl, carbonyl, and amine function groups. Results from this study can lead to better estimation of the fate and transport of antibiotics in the environment and has the potential to be utilized in designing engineering processes to remove tetracycline from water and soil. PMID:27420384

  8. Process configuration role in anaerobic biotransformations

    SciTech Connect

    Speece, R.E.

    1998-07-01

    Defining the environmental conditions which would enable anaerobic processes to consistently produce effluents containing only non-detectable concentrations of degradable organics would remove one of the main drawbacks to wider application of this important treatment technology. Recently specific metabolic intermediates formed in the anaerobic biotransformation of complex organics have been found to enhance or curtail process performance. Using acrylate and acrolein as representative hazardous chemicals, modifications in staging and reactor operation procedures have been observed in the author's laboratory to profoundly impact the rate and completeness of the biotransformation process. Specific metabolic intermediates formed in the biotransformation of complex substrates to a large extent will control a given process performance and process configuration greatly impacts the metabolic pathway, thus impacting the intermediates formed as well. There is a growing body of literature to indicate that process performance in anaerobic biotransformation is greatly impacted by reactor configuration. There is also some evidence that metabolic precursors impact the subsequent efficiency of conversion of volatile fatty acids (VFA) ultimately to CH{sub 4}. But although profound differences in the performance of anaerobic biotransformation are reported for various process configurations, there are no published criteria to guide the rational design of stages/phased processes. Clarification of the relative merits of single stage, two stage, two phase, granules and biofilms as well as CSTR and plug flow modes in the biotransformation of hazardous pollutants would be foundational for future research and development.

  9. Biotransformations of the cardiovascular drugs mexrenone and canrenone.

    PubMed

    Preisig, Carol L; Laakso, Jodi A; Mocek, Ursula M; Wang, Ping T; Baez, Julio; Byng, Graham

    2003-03-01

    Microbial transformation studies of the cardiovascular drugs mexrenone (1) and canrenone (2) were conducted. Thirty-nine biotransformations of mexrenone and 84 biotransformations of canrenone were analyzed. Metabolism of the substrate was observed in the majority of these cases. Several monohydroxylated derivatives were detected by HPLC-MS-UV and subsequently identified. Two new mexrenone derivatives, 11alpha- (3) and 12beta-hydroxymexrenone (4), and the known metabolite 6beta-hydroxymexrenone (5) were isolated as major products produced by the Beauveria bassiana ATCC 13144 bioconversion (3) and the Mortierella isabellina bioconversion (4 and 5), respectively. Single-elimination products were also sought; however, only the production of the known metabolite Delta(1,2)-mexrenone (6) by several bacteria was confirmed. One new monohydroxylated derivative of canrenone, 9alpha-hydroxycanrenone (7), was isolated as a major product from the Corynespora cassiicola bioconversion. Structure elucidation of all metabolites was based on NMR and HRMS analyses. PMID:12662091

  10. 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.

  11. 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.

  12. 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.

  13. Apprenticeship in Washington: Effective, Underutilized. Studies in Industry and Employment.

    ERIC Educational Resources Information Center

    Kamimura, Gary

    Washington's apprenticeship program was compared to other programs providing preparation for employment. The following were among the items considered in the comparative analysis: gains in job-specific skill competencies; relationship of training to postprogram employment; participant satisfaction; employer satisfaction; employment opportunities;…

  14. English Language Proficiency and Employment: A Case Study of Bangladeshi Graduates in Australian Employment Market

    ERIC Educational Resources Information Center

    Roshid, Mohammod Moninoor; Chowdhury, Raqib

    2013-01-01

    Recent literature has suggested that the relationship between globalisation and the English language implicates employability in the job market. Although the effects are uneven in different occupational groups and in different countries, such relationship is growing in significance to policy makers. This paper has explored the hitherto unstudied…

  15. Enantioselective Biotransformation of Chiral PCBs in Whole Poplar Plants

    PubMed Central

    Zhai, Guangshu; Hu, Dingfei; Lehmler, Hans-Joachim; Schnoor, Jerald L.

    2011-01-01

    Chiral PCBs have been used as molecular probes of biological metabolic processes due to their special physical, chemical and biological properties. Many animal studies showed the enantioselective biotransformation of chiral PCBs, but it is unclear whether plants can enantioselectively biotransform chiral PCBs. In order to explore the enantioselectivity of chiral PCBs in whole plants, poplars (Populus deltoides × nigra, DN34), a model plant with complete genomic sequence, were hydroponically exposed to 2,2′,3,5′,6-pentachlorobiphenyl (PCB95) and 2,2′,3,3′,6,6′-hexachlorobiphenyl (PCB136) for 20 days. PCB95 and PCB136 were shown to be absorbed, taken-up and translocated in whole poplars, and they were detected in various tissues of whole poplars. However, the enantioselectivity of poplar for PCB95 and PCB136 proved to be quite different. The first eluting enantiomer of PCB95 was enantioselectively removed in whole poplar, especially in the middle and bottom xylem. It was likely enantioselectively metabolized inside poplar tissues, in contrast to racemic mixtures of PCB95 remaining in hydroponic solutions in contact with plant roots of whole and dead poplars. Unlike PCB95, PCB136 remained nearly racemic in most parts of whole poplars after 20 days exposure. These results suggest that PCB136 is more difficult to be enantioslectively biotransformed than PCB95 in whole poplars. This is the first evidence of enantioselectivity of chiral PCBs in whole plants, and suggests that poplars can enantioselectively biotransform at least one chiral PCB. PMID:21329345

  16. 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.

  17. 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.

  18. 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. PMID:21456120

  19. Concentration dependence of biotransformation in fish liver S9: Optimizing substrate concentrations to estimate hepatic clearance for bioaccumulation assessment.

    PubMed

    Lo, Justin C; Allard, Gayatri N; Otton, S Victoria; Campbell, David A; Gobas, Frank A P C

    2015-12-01

    In vitro bioassays to estimate biotransformation rate constants of contaminants in fish are currently being investigated to improve bioaccumulation assessments of hydrophobic contaminants. The present study investigates the relationship between chemical substrate concentration and in vitro biotransformation rate of 4 environmental contaminants (9-methylanthracene, pyrene, chrysene, and benzo[a]pyrene) in rainbow trout (Oncorhynchus mykiss) liver S9 fractions and methods to determine maximum first-order biotransformation rate constants. Substrate depletion experiments using a series of initial substrate concentrations showed that in vitro biotransformation rates exhibit strong concentration dependence, consistent with a Michaelis-Menten kinetic model. The results indicate that depletion rate constants measured at initial substrate concentrations of 1 μM (a current convention) could underestimate the in vitro biotransformation potential and may cause bioconcentration factors to be overestimated if in vitro biotransformation rates are used to assess bioconcentration factors in fish. Depletion rate constants measured using thin-film sorbent dosing experiments were not statistically different from the maximum depletion rate constants derived using a series of solvent delivery-based depletion experiments for 3 of the 4 test chemicals. Multiple solvent delivery-based depletion experiments at a range of initial concentrations are recommended for determining the concentration dependence of in vitro biotransformation rates in fish liver fractions, whereas a single sorbent phase dosing experiment may be able to provide reasonable approximations of maximum depletion rates of very hydrophobic substances.

  20. Biotransformations of oxaliplatin in rat blood in vitro.

    PubMed

    Luo, F R; Wyrick, S D; Chaney, S G

    1999-01-01

    The partitioning and biotransformations of oxaliplatin [trans-l-1,2-diaminocyclohexaneoxalatoplatinum(II)] were investigated in the blood of Wistar male rats in vitro. [3-H]-Oxaliplatin was incubated with rat blood at 37 degrees C in 5% CO2 and the concentrations of all Pt complexes containing the [3-H]-dach carrier ligand were followed for up to 12 hours. Decay for both oxaliplatin and Pt-dach in the plasma ultrafiltrate (PUF) was rapid (t 1/2 oxaliplatin = 0.68 h and t 1/2 for Pt-dach in the PUF = 0.85 h). After 9 hours, the concentration of oxaliplatin fell below the detection limit. By 4 hours, the PUF-Pt-dach reached a plateau, which was 12% of total Pt-dach. The binding of Pt-dach to red blood cells (RBCs) and plasma proteins was also very rapid (t 1/2 RBCs = 0.58 h and t 1/2 plasma proteins = 0.78 h) and reached equilibrium by 4 hours. At equilibrium, 35% of total Pt-dach was bound to plasma proteins, 12% was in the plasma ultrafiltrate, and 53% was found associated with RBCs. Of the Pt-dach associated with RBCs, 23% was bound to the RBC membrane, 58% was bound to RBC cytosolic proteins, and 19% was in the RBC cytosol ultrafiltrate. Thus, these studies confirm previous observations of oxaliplatin accumulation by rat RBCs. To better characterize the determinants of this accumulation, oxaliplatin and other Pt-dach complexes were compared with respect to both their uptake by rat RBCs and their partition coefficients in octanol and water. The rank order for the rate of uptake was ormaplatin approximately Pt(dach)Cl2 > oxaliplatin > Pt(dach)(mal); while the rank order for hydrophobicity was ormaplatin > Pt(dach)Cl2 > Pt(dach)(mal) > oxaliplatin. Thus, in general, Pt-dach complexes appeared to be taken up better by RBCs than cisplatin or carboplatin, and the hydrophobicity of most of the Pt-dach complexes appeared to correlate with uptake. However, factors other than the dach carrier ligand and hydrophobicity clearly influence uptake. The biotransformations of

  1. Biotransformations of oxaliplatin in rat blood in vitro.

    PubMed

    Luo, F R; Wyrick, S D; Chaney, S G

    1999-01-01

    The partitioning and biotransformations of oxaliplatin [trans-l-1,2-diaminocyclohexaneoxalatoplatinum(II)] were investigated in the blood of Wistar male rats in vitro. [3-H]-Oxaliplatin was incubated with rat blood at 37 degrees C in 5% CO2 and the concentrations of all Pt complexes containing the [3-H]-dach carrier ligand were followed for up to 12 hours. Decay for both oxaliplatin and Pt-dach in the plasma ultrafiltrate (PUF) was rapid (t 1/2 oxaliplatin = 0.68 h and t 1/2 for Pt-dach in the PUF = 0.85 h). After 9 hours, the concentration of oxaliplatin fell below the detection limit. By 4 hours, the PUF-Pt-dach reached a plateau, which was 12% of total Pt-dach. The binding of Pt-dach to red blood cells (RBCs) and plasma proteins was also very rapid (t 1/2 RBCs = 0.58 h and t 1/2 plasma proteins = 0.78 h) and reached equilibrium by 4 hours. At equilibrium, 35% of total Pt-dach was bound to plasma proteins, 12% was in the plasma ultrafiltrate, and 53% was found associated with RBCs. Of the Pt-dach associated with RBCs, 23% was bound to the RBC membrane, 58% was bound to RBC cytosolic proteins, and 19% was in the RBC cytosol ultrafiltrate. Thus, these studies confirm previous observations of oxaliplatin accumulation by rat RBCs. To better characterize the determinants of this accumulation, oxaliplatin and other Pt-dach complexes were compared with respect to both their uptake by rat RBCs and their partition coefficients in octanol and water. The rank order for the rate of uptake was ormaplatin approximately Pt(dach)Cl2 > oxaliplatin > Pt(dach)(mal); while the rank order for hydrophobicity was ormaplatin > Pt(dach)Cl2 > Pt(dach)(mal) > oxaliplatin. Thus, in general, Pt-dach complexes appeared to be taken up better by RBCs than cisplatin or carboplatin, and the hydrophobicity of most of the Pt-dach complexes appeared to correlate with uptake. However, factors other than the dach carrier ligand and hydrophobicity clearly influence uptake. The biotransformations of

  2. Study on the Status Quo and Reform Measures of Employment Guidance in Universities

    ERIC Educational Resources Information Center

    He, Liping

    2011-01-01

    As a new discipline, employment guidance is aimed at the study of employment and how to solve the problem in employment every individual meets. It offers an effective approach to the problem in employment for university graduates. This article starts with the importance of conducting employment guidance and makes an analysis of the status quo as…

  3. Biotransformation of alkanoylcholines under methanogenic conditions.

    PubMed

    Watson, Mary Katherine; Tezel, Ulas; Pavlostathis, Spyros G

    2012-06-01

    Ester quaternary ammonium compounds (esterquats), which are mainly used as active ingredients in fabric softeners and personal care products, are beginning to replace traditional quaternary ammonium compounds. As a result of hydrophobicity and increasing use, esterquats reach anaerobic treatment systems. However, little is known about the fate of esterquats under anaerobic conditions. In the present study, the potential inhibitory effect and biotransformation of two alkanoylcholines - acetylcholine chloride (ACh-Cl) and lauroylcholine chloride (LCh-Cl) - which are simple esterquats, under methanogenic conditions were investigated. ACh-Cl up to 300 mg/L was not inhibitory to a mixed methanogenic culture. In contrast, methanogenesis was inhibited by LCh-Cl above 50 mg/L, primarily caused by the accumulation of lauric acid which resulted from the abiotic hydrolysis of LCh. Below inhibitory concentrations, both ACh and LCh were transformed to methane by the mixed methanogenic culture. Mass spectrometric analysis confirmed that both alkanoylcholines were first abiotically hydrolyzed to choline and the corresponding alkanoic acid, which were then biotically transformed to methane, carbon dioxide, and ammonia. Thus, alkanoylcholine-containing waste streams can be bioprocessed to form methane, but hydrolysis products such as long-chain alkanoic acids may adversely impact the anaerobic bioconversion of alkanoylcholines. PMID:22463863

  4. Arsenic biotransformation and volatilization in transgenic rice.

    PubMed

    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

    2011-07-01

    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) cv 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 roots and shoots of transgenic rice. After 12 d exposure to As(III), the transgenic rice gave off 10-fold greater volatile arsenicals. • The present study demonstrates that expression of an arsM gene in rice induces arsenic methylation and volatilization, theoretically providing a potential stratagem for phytoremediation. PMID:21517874

  5. 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…

  6. 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…

  7. 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…

  8. 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

  9. 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

    2014-05-01

    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.

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

    PubMed Central

    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. PMID:26330881

  11. Biotransformation of benzimidazole anthelmintics in reed (Phragmites australis) as a potential tool for their detoxification in environment.

    PubMed

    Podlipná, Radka; Skálová, Lenka; Seidlová, Helena; Szotáková, Barbora; Kubíček, Vladimír; Stuchlíková, Lucie; Jirásko, Robert; Vaněk, Tomáš; Vokřál, Ivan

    2013-09-01

    Benzimidazole anthelmintics, the drugs against parasitic worms, are widely used in human as well as veterinary medicine. Following excretion, these substances may persist in the environment and impact non-target organisms. In order to test phytoremediation as a possible tool for detoxification of anthelmintics in environment, the biotransformation pathways of albendazole (ABZ) and flubendazole (FLU) were studied in reed (Phragmites australis) in vitro. Reed cells were able to uptake and biotransform both anthelmintics. Ten ABZ metabolites and five FLU metabolites were found. Some atypical biotransformation reactions (formation of glucosylglucosides, acetylglucosides and xylosylglucosides), which have not been described previously, were identified. Based on the obtained results, the schemes of metabolic pathways of ABZ and FLU in reed were proposed. Most of ABZ and FLU metabolites can be considered as anthelmintically less active; therefore uptake and biotransformation of these anthelmintics by reed could be useful for decrease of their toxicity in environment.

  12. 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

  13. The potential of cloud point system as a novel two-phase partitioning system for biotransformation.

    PubMed

    Wang, Zhilong

    2007-05-01

    Although the extractive biotransformation in two-phase partitioning systems have been studied extensively, such as the water-organic solvent two-phase system, the aqueous two-phase system, the reverse micelle system, and the room temperature ionic liquid, etc., this has not yet resulted in a widespread industrial application. Based on the discussion of the main obstacles, an exploitation of a cloud point system, which has already been applied in a separation field known as a cloud point extraction, as a novel two-phase partitioning system for biotransformation, is reviewed by analysis of some topical examples. At the end of the review, the process control and downstream processing in the application of the novel two-phase partitioning system for biotransformation are also briefly discussed. PMID:17318534

  14. 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.

  15. 77 FR 2349 - Proposed Information Collection (Vocational Rehabilitation and Employment Longitudinal Study...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-17

    ... AFFAIRS Proposed Information Collection (Vocational Rehabilitation and Employment Longitudinal Study... . Please refer to ``OMB Control No. 2900--New (VR&E Longitudinal Study Survey)'' in any correspondence...: Vocational Rehabilitation and Employment Longitudinal Study Survey. OMB Control Number: 2900--New...

  16. 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

  17. Novel biotransformation and physiological properties of norursodeoxycholic acid in humans.

    PubMed

    Hofmann, Alan F; Zakko, Salam F; Lira, Marco; Clerici, Carlo; Hagey, Lee R; Lambert, K Karel; Steinbach, Joseph H; Schteingart, Claudio D; Olinga, Peter; Groothuis, Geny M M

    2005-12-01

    Experiments were performed in 2 volunteers to define the biotransformation and physiological properties of norursodeoxycholic acid (norUDCA), the C(23) (C(24)-nor) homolog of UDCA. To complement the in vivo studies, the biotransformation of norUDCA ex vivo using precision-cut human liver slices was also characterized. In the human studies, both a tracer dose given intravenously and a physiological dose (7.9 mmol, 3.0 g) given orally were excreted equally in bile and urine. By chromatography and mass spectrometry, the dominant biotransformation product of norUDCA in bile and urine was the C-23 ester glucuronide. Little N-acyl amidation (with glycine or taurine) occurred. The oral dose induced a sustained bicarbonate-rich hypercholeresis, with total bile flow averaging 20 microL/kg/min, a rate extrapolating to 2 L/d. The increased bile flow was attributed to cholehepatic shunting of norUDCA as well to the lack of micelles in bile. Phospholipid and cholesterol secretion relative to bile acid secretion decreased during secretion of norUDCA and its metabolites, presumably also because of the absence of micelles in canalicular bile. When incubated with human liver slices, norUDCA was glucuronidated, whereas UDCA was conjugated with glycine or taurine. In conclusion, in humans, norUDCA is glucuronidated rather than amidated. In humans, but not animals, there is considerable renal elimination of the C-23 ester glucuronide, the dominant metabolite. NorUDCA ingestion induces a bicarbonate-rich hypercholeresis and evokes less phospholipid and cholesterol secretion into bile than UDCA. Molecules that undergo cholehepatic shunting should be powerful choleretics in humans.

  18. 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.

  19. 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. PMID:25461743

  20. 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.

  1. Employers' Interest in Workplace Literacy Education Services: A Nevada Study.

    ERIC Educational Resources Information Center

    Ramakka, Vicky F.; And Others

    1995-01-01

    A survey of 2,021 Nevada employers received 1,124 usable responses indicating significant differences in their interest in adult basic education services. Larger organizations were more interested (57% of those with more than 500 employees). They were most interested in methods to encourage attendance and in availability of information about…

  2. 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…

  3. 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…

  4. Youth Employment Programs in the Southwest. Three Case Studies.

    ERIC Educational Resources Information Center

    Briggs, Vernon M., Jr.

    This report presents planning, implementation, and first-year operational phases of Youth Employment and Demonstration Projects Act (YEDPA) programs by prime sponsors in the Southwest. The prime sponsors were the city of Albuquerque and the encompassing county of Bernalillo, New Mexico; the Coastal Bend Manpower Consortium Area in Texas…

  5. [A study on the relationship between women's employment and fertility].

    PubMed

    Cho, A J; Kong, S K

    1988-07-01

    The Korean Family Life Cycle Survey data on women's employment are used to explore variations in women's employment patterns and the relationship between women's employment and fertility. In general, employment rates increase with women's age. Women in rural areas are more likely to work than those in urban areas. These patterns are clearly linked to different work opportunity structures. As a rule, the most educated and the least educated are more likely to work, whereas respondents in the middle educational categories were least likely. It has already been recognized that the employment period during the life course may be related to fertility in various ways. 1 is delay of marriage among women who work before they marry. The relatively better financial situation of unmarried working women contributes to the desire to extend single life compared with non-working women. In addition, particular types of work may provide exposure to ideas and norms that discourage early marriage. It may also be true that single working women who contribute to household income have some influence on women's decision to postpone marriage. The results show that women who work before marriage marry somewhat later than women who never work before marriage. For example, women who were in professional and clerical occupations married about 3 years later than women who had not worked before marriage. Among women who had been employed before marriage, age at marriage differed according to different occupations. For example, women with working experience in professional and clerical occupations had the highest mean age at marriage. An analysis of the relationship between women's employment and fertility shows that women in professional and clerical work bear somewhat fewer children on average than women with no recorded economic activity. In domestic household employee and agricultural work, however, no such relationship is observed. The relationship between occupation and fertility is

  6. Biotransformation of bioactive isocaryolanes by Botrytis cinerea.

    PubMed

    Ascari, Jociani; Boaventura, Maria Amélia Diamantino; Takahashi, Jacqueline Aparecida; Durán-Patrón, Rosa; Hernández-Galán, Rosario; Macías-Sánchez, Antonio J; Collado, Isidro G

    2011-08-26

    The metabolism of the fungistatic agent (8R,9R)-8-methoxyisocaryolan-9-ol (4) by the fungus Botrytis cinerea has been investigated. Biotransformation of compound 4 yielded compounds 5 and 6-9. No dihydrobotrydial is observed after 4 days of incubation of compound 4. Separate biotransformation of (8R,9R)-isocaryolane-8,9-diol (5) yielded compounds 7-11. The evaluation of the fungistatic activity against B. cinerea of compounds 4, 5, and 6 is reported. (4R,8R,9R)-8-Methoxyisocaryolane-9,15-diol (6), a major metabolite of (8R,9R)-8-methoxyisocaryolan-9-ol (4), shows a much reduced biological activity when compared with the parent compound. Isocaryolane derivatives 6-11 are described for the first time.

  7. Biotransformation of Flurbiprofen by Cunninghamella Species▿

    PubMed Central

    Amadio, Jessica; Gordon, Katherine; Murphy, Cormac D.

    2010-01-01

    The biotransformation of the fluorinated anti-inflammatory drug flurbiprofen was investigated in Cunninghamella spp. Mono- and dihydroxylated metabolites were detected using gas chromatography-mass spectrometry and fluorine-19 nuclear magnetic resonance spectroscopy, and the major metabolite 4′-hydroxyflurbiprofen was isolated by preparative high-pressure liquid chromatography (HPLC). Cunninghamella elegans DSM 1908 and C. blakesleeana DSM 1906 also produced a phase II (conjugated) metabolite, which was identified as the sulfated drug via deconjugation experiments. PMID:20656862

  8. Biotransformation of (+/-)-2-methylcyclohexanone by fungi.

    PubMed

    Kawamoto, Mai; Utsukihara, Takamitsu; Abe, Chika; Sato, Michiko; Saito, Michihiko; Koshimura, Masahiro; Kato, Nakahide; Horiuchi, C Akira

    2008-09-01

    The biotransformation of 2-methylcyclohexanone (1) using 16 fungal strains and some mushroom cultures was investigated. Fusarium sp. was one of the effective biocatalysts for oxidoreduction of 2-methylcyclohexanone (1). cis-2-Methylcyclohexanol (2a) was isomerized to trans-2-methylcyclohexanol (2b) by Fusarium sp. In addition, the corresponding lactones 3 was obtained by Baeyer-Villiger oxidation using Fusarium sp. AP-2 (46%, 94% ee).

  9. 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.

  10. The role of biotransformation and bioactivation in toxicity.

    PubMed

    Dekant, Wolfgang

    2009-01-01

    Biotransformation is essential to convert lipophilic chemicals to water-soluble and readily excretable metabolites. Formally, biotransformation reactions are classified into phase I and phase II reactions. Phase I reactions represent the introduction of functional groups, whereas phase II reactions are conjugations of such functional groups with endogenous, polar products. Biotransformation also plays an essential role in the toxicity of many chemicals due to the metabolic formation of toxic metabolites. These may be classified as stable but toxic products, reactive electrophiles, radicals, and reactive oxygen metabolites. The interaction of toxic products formed by biotransformation reactions with cellular macromolecules initiates the sequences resulting in cellular damage, cell death and toxicity.

  11. 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.

  12. 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...

  13. 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.

  14. Biodefluorination and biotransformation of fluorotelomer alcohols by two alkane-degrading Pseudomonas strains.

    PubMed

    Kim, Myung Hee; Wang, Ning; McDonald, Thomas; Chu, Kung-Hui

    2012-12-01

    Fluorotelomer alcohols [FTOHs, F(CF(2))(n) CH(2)CH(2)OH, n = 4, 6, and 8] are emerging environmental contaminants. Biotransformation of FTOHs by mixed bacterial cultures has been reported; however, little is known about the microorganisms responsible for the biotransformation. Here we reported biotransformation of FTOHs by two well-studied Pseudomonas strains: Pseudomonas butanovora (butane oxidizer) and Pseudomonas oleovorans (octane oxidizer). Both strains could defluorinate 4:2, 6:2, and 8:2 FTOHs, with a higher degree of defluorination for 4:2 FTOH. According to the identified metabolites, P. oleovorans transformed FTOHs via two pathways I and II. The pathway I led to the production of x:2 ketone [dominant metabolite, F(CF(2))(x)C(O)CH(3); x = n - 1, n = 6 or 8], x:2 sFTOH [F(CF(2))(x)CH(OH)CH(3)], and perfluorinated carboxylic acids (PFCAs, perfluorohexanoic, or perfluorooctanoic acid). The pathway II resulted in the formation of x:3 polyfluorinated acid [F(CF(2))(x) C(2)CH(2) COOH] and relatively minor shorter-chain PFCAs (perfluorobutyric or perfluorohexanoic acid). Conversely, P. butanovora transformed FTOHs by using the pathway I, leading to the production of x:2 ketone, x:2 sFTOH, and PFCAs. This is the first study to show that individual bacterium can bio-transform FTOHs via different or preferred transformation pathways to remove multiple --CF(2) -- groups from FTOHs to form shorter-chain PFCAs. PMID:22614340

  15. 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.

  16. (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

    2016-03-01

    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.

  17. 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. PMID:27584085

  18. 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…

  19. What Do Employment Specialists Really Do? A Study on Job Development Practices

    ERIC Educational Resources Information Center

    Migliore, Alberto; Hall, Allison Cohen; Butterworth, John; Winsor, Jean

    2010-01-01

    This study examined the extent to which employment specialists implemented the job development practices recommended in the research literature when assisting job seekers with intellectual or developmental disabilities. Self-reported data were collected through a Web-based survey from 163 employment specialists from 74 employment programs in 28…

  20. 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…

  1. 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…

  2. Diversity and abundance of arsenic biotransformation genes in paddy soils from southern China.

    PubMed

    Zhang, Si-Yu; Zhao, Fang-Jie; Sun, Guo-Xin; Su, Jian-Qiang; Yang, Xiao-Ru; Li, Hu; Zhu, Yong-Guan

    2015-04-01

    Microbe-mediated arsenic (As) biotransformation in paddy soils determines the fate of As in soils and its availability to rice plants, yet little is known about the microbial communities involved in As biotransformation. Here, we revealed wide distribution, high diversity, and abundance of arsenite (As(III)) oxidase genes (aioA), respiratory arsenate (As(V)) reductase genes (arrA), As(V) reductase genes (arsC), and As(III) S-adenosylmethionine methyltransferase genes (arsM) in 13 paddy soils collected across Southern China. Sequences grouped with As biotransformation genes are mainly from rice rhizosphere bacteria, such as some Proteobacteria, Gemmatimonadales, and Firmicutes. A significant correlation of gene abundance between arsC and arsM suggests that the two genes coexist well in the microbial As resistance system. Redundancy analysis (RDA) indicated that soil pH, EC, total C, N, As, and Fe, C/N ratio, SO4(2-)-S, NO3(-)-N, and NH4(+)-N were the key factors driving diverse microbial community compositions. This study for the first time provides an overall picture of microbial communities involved in As biotransformation in paddy soils, and considering the wide distribution of paddy fields in the world, it also provides insights into the critical role of paddy fields in the As biogeochemical cycle.

  3. Diversity and abundance of arsenic biotransformation genes in paddy soils from southern China.

    PubMed

    Zhang, Si-Yu; Zhao, Fang-Jie; Sun, Guo-Xin; Su, Jian-Qiang; Yang, Xiao-Ru; Li, Hu; Zhu, Yong-Guan

    2015-04-01

    Microbe-mediated arsenic (As) biotransformation in paddy soils determines the fate of As in soils and its availability to rice plants, yet little is known about the microbial communities involved in As biotransformation. Here, we revealed wide distribution, high diversity, and abundance of arsenite (As(III)) oxidase genes (aioA), respiratory arsenate (As(V)) reductase genes (arrA), As(V) reductase genes (arsC), and As(III) S-adenosylmethionine methyltransferase genes (arsM) in 13 paddy soils collected across Southern China. Sequences grouped with As biotransformation genes are mainly from rice rhizosphere bacteria, such as some Proteobacteria, Gemmatimonadales, and Firmicutes. A significant correlation of gene abundance between arsC and arsM suggests that the two genes coexist well in the microbial As resistance system. Redundancy analysis (RDA) indicated that soil pH, EC, total C, N, As, and Fe, C/N ratio, SO4(2-)-S, NO3(-)-N, and NH4(+)-N were the key factors driving diverse microbial community compositions. This study for the first time provides an overall picture of microbial communities involved in As biotransformation in paddy soils, and considering the wide distribution of paddy fields in the world, it also provides insights into the critical role of paddy fields in the As biogeochemical cycle. PMID:25738639

  4. 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.

  5. Direct Biotransformation of Dioscin into Diosgenin in Rhizome of Dioscorea zingiberensis by Penicillium dioscin.

    PubMed

    Dong, Jingzhou; Lei, Can; Lu, Dayan; Wang, Ying

    2015-06-01

    Diosgenin is an important precursor for synthesis of more than 200 steroidal hormone medicines. Rhizome of Dioscorea zingiberensis C. H. Wright (RDZ) contained the highest content of diosgenin in Dioscorea plant species. Diosgenin is traditionally extracted by acid hydrolysis from RDZ. However, the acid hydrolysis process produces massive wastewater which caused serious environment pollution. In this study, diosgenin extraction by direct biotransformation with Penicillium dioscin was investigated. The spawn cultivation conditions were optimized as: Czapeks liquid culture medium without sugar and agar (1,000 ml) + 6.0 g dioscin/6.0 g DL, 30 °C, 36 h; solid fermentation of RDZ: mycelia/RDZ of 0.05 g/kg, 30 °C, 50 h; the yield of diosgenin was over 90 %. Spawn cultivation was crucial for the direct biotransformation. In the spawn cultivation, amount and ratio of dioscin/DL were the key factors to promote biotransformation activity of P. dioscin. This biotransformation method was environment-friendly, simple and energy saving, and might be a potential substitute for acid hydrolysis in diosgenin extraction industry. PMID:25805907

  6. 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

  7. 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. PMID:26766368

  8. 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.

  9. 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…

  10. 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

  11. 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

    2015-07-01

    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. PMID:26042823

  12. 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

  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. 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.

  15. 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

  16. 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.

  17. TNT biotransformation: when chemistry confronts mineralization.

    PubMed

    Smets, Barth F; Yin, Hong; Esteve-Nuñez, Abraham

    2007-08-01

    Our understanding of the genetics and biochemistry of microbial 2,4,6-trinitrotoluene (TNT) biotransformation has advanced significantly during the past 10 years, and biotreatment technologies have developed. In this review, we summarize this new knowledge. A number of enzyme classes involved in TNT biotransformation include the type I nitroreductases, the old yellow enzyme family, a respiration-associated nitroreductase, and possibly ring hydroxylating dioxygenases. Several strains harbor dual pathways: nitroreduction (reduction of the nitro group in TNT to a hydroxylamino and/or amino group) and denitration (reduction of the aromatic ring of TNT to Meisenheimer complexes with nitrite release). TNT can serve as a nitrogen source for some strains, and the postulated mechanism involves ammonia release from hydroxylamino intermediates. Field biotreatment technologies indicate that both stimulation of microbial nitroreduction and phytoremediation result in significant and permanent immobilization of TNT via its metabolites. While the possibility for TNT mineralization was rekindled with the discovery of TNT denitration and oxygenolytic and respiration-associated pathways, further characterization of responsible enzymes and their reaction mechanisms are required.

  18. Arsenic biotransformation in earthworms from contaminated soils.

    PubMed

    Button, Mark; Jenkin, Gawen R T; Harrington, Chris F; Watts, Michael J

    2009-08-01

    Two species of arsenic (As) resistant earthworm, Lumbricus rubellus and Dendrodrillus rubidus, their host soils and soil excretions (casts) were collected from 23 locations at a former As mine in Devon, UK. Total As concentrations, measured by ICP-MS, ranged from 255 to 13,080 mg kg(-1) in soils, 11 to 877 mg kg(-1) in earthworms and 284 to 4221 mg kg(-1) in earthworm casts from a sub-sample of 10 of the 23 investigated sites. The samples were also measured for As speciation using HPLC-ICP-MS to investigate potential As biotransformation pathways. Inorganic arsenate (As(V)) and arsenite (As(III)) were the only species detected in the soil. As(V) and As(III) were also the dominant species found in the earthworms and cast material together with lower proportions of the organic species methylarsonate (MA(V)), dimethylarsinate (DMA(V)), arsenobetaine (AB) and three arsenosugars. Whilst the inorganic As content of the earthworms increased with increasing As body burden, the concentration of organic species remained relatively constant. These results suggest that the biotransformation of inorganic arsenic to organic species does not contribute to As resistance in the sampled earthworm populations. Quantification of As speciation in the soil, earthworms and cast material allows a more comprehensive pathway for the formation of AB in earthworms to be elucidated. PMID:19657532

  19. Microbial Biotransformation to Obtain New Antifungals.

    PubMed

    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

  20. 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.

  1. 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…

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

    PubMed Central

    2014-01-01

    Background 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. Methods 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. Results 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. Conclusion 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. PMID:24885230

  3. 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.

  4. 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…

  5. 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…

  6. Modelling cometabolic biotransformation of organic micropollutants in nitrifying reactors.

    PubMed

    Fernandez-Fontaina, E; Carballa, M; Omil, F; Lema, J M

    2014-11-15

    Cometabolism is the ability of microorganisms to degrade non-growth substrates in the presence of primary substrates, being the main removal mechanism behind the biotransformation of organic micropollutants in wastewater treatment plants. In this paper, a cometabolic Monod-type kinetics, linking biotransformation of micropollutants with primary substrate degradation, was applied to a highly enriched nitrifying activated sludge (NAS) reactor operated under different operational conditions (hydraulic retention time (HRT) and nitrifying activity). A dynamic model of the bioreactor was built taking into account biotransformation, sorption and volatilization. The micropollutant transformation capacity (Tc), the half-saturation constant (Ksc) and the solid-liquid partitioning coefficient (Kd) of several organic micropollutants were estimated at 25 °C using an optimization algorithm to fit experimental data to the proposed model with the cometabolic Monod-type biotransformation kinetics. The cometabolic Monod-type kinetic model was validated under different HRTs (1.0-3.7 d) and nitrification rates (0.12-0.45 g N/g VSS d), describing more accurately the fate of those compounds affected by the biological activity of nitrifiers (ibuprofen, naproxen, erythromycin and roxithromycin) compared to the commonly applied pseudo-first order micropollutant biotransformation kinetics, which does not link biotransformation of micropollutants to consumption of primary substrate. Furthermore, in contrast to the pseudo-first order biotransformation constant (k(biol)), the proposed cometabolic kinetic coefficients are independent of operational conditions such as the nitrogen loading rate applied. Also, the influence of the kinetic parameters on the biotransformation efficiency of NAS reactors, defined as the relative amount of the total inlet micropollutant load being biotransformed, was assessed considering different HRTs and nitrification rates.

  7. Modelling cometabolic biotransformation of organic micropollutants in nitrifying reactors.

    PubMed

    Fernandez-Fontaina, E; Carballa, M; Omil, F; Lema, J M

    2014-11-15

    Cometabolism is the ability of microorganisms to degrade non-growth substrates in the presence of primary substrates, being the main removal mechanism behind the biotransformation of organic micropollutants in wastewater treatment plants. In this paper, a cometabolic Monod-type kinetics, linking biotransformation of micropollutants with primary substrate degradation, was applied to a highly enriched nitrifying activated sludge (NAS) reactor operated under different operational conditions (hydraulic retention time (HRT) and nitrifying activity). A dynamic model of the bioreactor was built taking into account biotransformation, sorption and volatilization. The micropollutant transformation capacity (Tc), the half-saturation constant (Ksc) and the solid-liquid partitioning coefficient (Kd) of several organic micropollutants were estimated at 25 °C using an optimization algorithm to fit experimental data to the proposed model with the cometabolic Monod-type biotransformation kinetics. The cometabolic Monod-type kinetic model was validated under different HRTs (1.0-3.7 d) and nitrification rates (0.12-0.45 g N/g VSS d), describing more accurately the fate of those compounds affected by the biological activity of nitrifiers (ibuprofen, naproxen, erythromycin and roxithromycin) compared to the commonly applied pseudo-first order micropollutant biotransformation kinetics, which does not link biotransformation of micropollutants to consumption of primary substrate. Furthermore, in contrast to the pseudo-first order biotransformation constant (k(biol)), the proposed cometabolic kinetic coefficients are independent of operational conditions such as the nitrogen loading rate applied. Also, the influence of the kinetic parameters on the biotransformation efficiency of NAS reactors, defined as the relative amount of the total inlet micropollutant load being biotransformed, was assessed considering different HRTs and nitrification rates. PMID:25150522

  8. 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 .

  9. 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.

  10. 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. PMID:20214593

  11. 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.

  12. Toxicity, bioaccumulation, and biotransformation of silver nanoparticles in marine organisms.

    PubMed

    Wang, Huanhua; Ho, Kay T; Scheckel, Kirk G; Wu, Fengchang; Cantwell, Mark G; Katz, David R; Horowitz, Doranne Borsay; Boothman, Warren S; Burgess, Robert M

    2014-12-01

    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 AgNP-citrate and AgNP-PVP did not exhibit toxicity to the amphipod (Ampelisca abdita) and mysid (Americamysis bahia) at ≤75 mg/kg dry wt. A 28-d bioaccumulation study showed that Ag was significantly accumulated in the marine polychaete Nereis virens (N. virens) in the AgNP-citrate, AgNP-PVP and a conventional salt (AgNO3) treatments. Synchrotron X-ray absorption spectroscopy (XAS) results showed the distribution of Ag species in marine sediments amended with AgNP-citrate, AgNP-PVP, and AgNO3 was AgCl (50–65%) > Ag2S (32–42%) > Ag metal (Ag0) (3–11%). In N virens, AgCl (25–59%) and Ag2S (10–31%) generally decreased and, Ag metal (32–44%) increased, relative to the sediments. The patterns of speciation in the worm were different depending upon the coating of the AgNP and both types of AgNPs were different than the AgNO3 salt. These results show that the AgNP surface capping agents influenced Ag uptake, biotransformation, and/or excretion. To our knowledge, this is the first demonstration of the bioaccumulation and speciation of AgNPs in a marine organism (N. virens).

  13. Reductive amination by recombinant Escherichia coli: whole cell biotransformation of 2-keto-3-methylvalerate to L-isoleucine.

    PubMed

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

    2013-11-01

    A whole cell biotransformation system for reductive amination has been studied in recombinant Escherichia coli cells. Reductive amination of 2-keto-3-methylvalerate to L-isoleucine by a two-enzyme-cascade was achieved by overproduction of endogenous L-alanine dependent transaminase AvtA and heterologous L-alanine dehydrogenase from Bacillus subtilis in recombinant E. coli. Up to 100 mM L-isoleucine were produced from 100 mM 2-keto-3-methylvalerate and 100 mM ammonium sulfate. Regeneration of NADH as cofactor in the whole cell system was driven by glucose catabolism. The effects of defined gene deletions in the central carbon metabolism on biotransformation were tested. Strains lacking the NuoG subunit of NADH:ubiquinone oxidoreductase (complex I) or aceA encoding the glyoxylate cycle enzyme isocitrate lyase exhibited increased biotransformation rates.

  14. 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. PMID:26189577

  15. 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.

  16. Studies on drug metabolism by fungi colonizing decomposing human cadavers. Part II: biotransformation of five model drugs by fungi isolated from post-mortem material.

    PubMed

    Martínez-Ramírez, Jorge A; Walther, Grit; Peters, Frank T

    2015-04-01

    The present study investigated the in vitro metabolic capacity of 28 fungal strains isolated from post-mortem material towards five model drugs: amitriptyline, metoprolol, mirtazapine, promethazine, and zolpidem. Each fungal strain was incubated at 25 °C for up to 120 h with each of the five models drugs. Cunninghamella elegans was used as positive control. Aliquots of the incubation mixture were centrifuged and 50 μL of the supernatants were diluted and directly analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) with product ion scanning. The remaining mixture was analyzed by full scan gas chromatography-mass spectrometry (GC-MS) after liquid-liquid extraction and acetylation. The metabolic activity was evaluated through the total number of detected metabolites (NDM) produced in each model and fungal strains and the percentage of parent drug remaining (%RPD) after up to five days of incubation. All the tested fungal strains were capable of forming mammalian phase I metabolites. Fungi from the normal fungal flora of the human body such as Candida sp., Geotrichum candidum, and Trichosporon asahii) formed up to seven metabolites at %RPD values greater than 52% but no new fungal metabolites (NFM). In contrast, some airborne fungal strains like Bjerkandera adusta, Chaetomium sp, Coriolopsis sp., Fusarium solani and Mucor plumbeus showed NDM values exceeding those of the positive control, complete metabolism of the parent drug in some models and formation of NFM. NFM (numbers in brackets) were detected in four of the five model drugs: amitriptyline (18), metoprolol (4), mirtazapine (8), and zolpidem (2). The latter NFM are potential candidates for marker substances indicating post-mortem fungal metabolism. PMID:24898183

  17. University Studies as a Side Job: Causes and Consequences of Massive Student Employment in Estonia

    ERIC Educational Resources Information Center

    Beerkens, Maarja; Magi, Eve; Lill, Liis

    2011-01-01

    Student employment is increasingly common in many countries. Compared to earlier decades, not only more students work but they also work longer hours. Among European countries Estonia is one of the clear "leaders" in student employment. This study uses survey data from 2,496 students in Estonian public and private universities to examine the…

  18. 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…

  19. A Pilot Study for Gainful Employment in Home Economics. Final Report. Volume I.

    ERIC Educational Resources Information Center

    Cozine, June; And Others

    The major purpose of the study was to develop and test curriculum materials for three entry level gainful employment courses: Child Care Services, Clothing Services, Food Services. A second objective was to formulate recommendations for policies and procedures to follow in initiating and developing gainful employment programs in home economics.…

  20. 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…

  1. Factors affecting the biotransformation of TNT

    SciTech Connect

    Wilber, G.G.; Li, J.; Clarkson, W.W.

    1999-07-01

    Experiments were performed investigating several of the factors the effect the biotransformation of 2,4,6-trinitrotoluene in soils and groundwater. Three different electron acceptor conditions (nitrate-reducing, sulfate-reducing, and fermentative) were tested, as were several other variables in the reactor medium. All three anaerobic conditions were found favorable for TNT transformation, though nitrate-reducing conditions appeared to be fastest. Under nitrate-reducing conditions, TNT transformation rates were directly proportionally to primary substrate (acetate) concentrations. In the presence of bisulfide, TNT reacted rapidly in an abiotic reaction. Sulfate reduction and methanogenesis in the fermentative reactors were inhibited by TNT concentrations above 100 mg/L. The pattern on nitro-group reduction was reasonably predictable, with the more reduced products degrading fastest under nitrate-reducing conditions.

  2. 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.

  3. Designing a whole-cell biotransformation system in Escherichia coli using cytochrome P450 from Streptomyces peucetius.

    PubMed

    Shrestha, Pramod; Oh, Tae-Jin; Sohng, Jae Kyung

    2008-06-01

    A biotransformation system was designed to co-express CYP107P3 (CSP4), cytochrome P450, from Streptomyces peuceticus, along with CamA (putidaredoxin reductase) and CamB (putidaredoxin) from Pseudomonas putida, the necessary reducing equivalents, in a class I type electron-transfer system in E. coli BL21 (DE3). This was carried out using two plasmids with different selection markers and compatible origins of replication. The study results showed that this biotransformation system was able to mediate the O-dealkylation of 7-ethoxycumarin. PMID:18259876

  4. 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.

  5. 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.

  6. 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...

  7. 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

  8. 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…

  9. 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…

  10. 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.

  11. Biotransformation of pink water TNT on the surface of a low-cost adsorbent pine bark.

    PubMed

    Chusova, O; Nõlvak, H; Odlare, M; Truu, J; Truu, M; Oopkaup, K; Nehrenheim, E

    2015-09-01

    This two-week anaerobic batch study evaluated 2,4,6-trinitrotoluene (TNT) removal efficiency from industrial pink water by (1) adsorption on low-cost adsorbent pine bark, and (2) adsorption coupled with TNT biotransformation by specialised microbial communities. Samples of the supernatant and acetonitrile extracts of pine bark were analysed by HPLC, while the composition of the bacterial community of the experimental batches, inocula and pine bark were profiled by high-throughput sequencing the V6 region of the bacterial 16S rRNA gene. Integrated adsorption and biotransformation proved to be the most efficient method for TNT removal from pink water. The type of applied inoculum had a profound effect on TNT removal efficiencies and microbial community structures, which were dominated by phylotypes belonging to the Enterobacteriaceae family. The analysis of acetonitrile extracts of pine bark supported the hypothesis that the microbial community indigenous to pine bark has the ability to degrade TNT. PMID:26142875

  12. In vitro cytotoxicity of aromatic aerobic biotransformation products in bluegill sunfish BF-2 cells.

    PubMed

    Shen, Y; West, C; Hutchins, S R

    2000-01-01

    Toluene (methylbenzene) is a common environmental pollutant that is found in many hazardous waste sites and it is an aquifer contaminant. A concern is the potential risk to human and ecosystem health due to exposure to toluene and its major biotransformation products. The cytotoxicity of eight aromatic products of toluene aerobic biotransformation was investigated in bluegill sunfish BF-2 cells. The cytotoxicity was determined using several in vitro assay endpoints. BF-2 cells were propagated at 32 degrees C in an atmosphere of 5% CO2-95% air. The concentrations of these products causing 50% inhibition in cell replication, protein content, uptake of natural red, and colony formation were evaluated and compared. The results of the study indicate a direct relationship between the exposure concentration of these products and observed cytotoxic effects. In descending order of cytotoxicity, the compounds were 3-methylcatechol, 4-methylcatechol, catechol, o-cresol, p-cresol, m-cresol, benzaldehyde, and methyl benzoate.

  13. Biotransformation of tetrabromobisphenol A (TBBPA) in anaerobic digester sludge, soils, and freshwater sediments.

    PubMed

    McAvoy, Drew C; Pittinger, Charles A; Willis, Alison M

    2016-09-01

    The biotransformation of tetrabromobisphenol A (TBBPA) was evaluated in anaerobic digester sludge, soils, and freshwater sediments. In anaerobic digester sludge, TBBPA biotransformed rapidly with a 50% disappearance time (DT50) of 19 days, though little mineralization (1.1%) was observed. In aerobic soils, mineralization of TBBPA ranged from 17.5% to 21.6% with 55.3-83.6% of the TBBPA incorporated into the soils as a non-extractable bound residue. The DT50 for TBBPA in aerobic soils ranged from 5.3 to 7.7 days. In anaerobic soils, 48.3-100% of the TBBPA was incorporated into the soils as non-extractable bound residue with <4% mineralized. The soil fate studies demonstrated extensive incorporation of TBBPA into the solid matrix and this association was related to the amount of organic carbon in the soils (i.e., greater association of TBBPA with soil at higher organic carbon content). In anaerobic sediments the DT50 for TBBPA ranged from 28 to 42 days, whereas in aerobic sediments the DT50 for TBBPA ranged from 48 to 84 days and depended on the initial dose concentration. Most of the TBBPA in the sediment studies was incorporated as a non-extractable bound residue with little mineralization observed. Sediment extracts revealed three unknown biotransformation products and bisphenol A (BPA). These results were consistent with previously published studies where TBBPA biotransformed in anaerobic environments (digester sludge and sediments) by debromination and slowly mineralized in the test environments (anaerobic digester sludge, soils, and freshwater sediments).

  14. Xenobiotic biotransformation in livestock: comparison to other species commonly used in toxicity testing.

    PubMed

    Watkins, J B; Klaassen, C D

    1986-09-01

    Wildlife, domesticated animals and humans are exposed daily to myriad chemicals present in our environment. The risk posed by these chemicals to one species is often determined by extrapolation from data gathered from another species. Several extensive studies have examined the capability of the liver to biotransform xenobiotics in animals commonly used in toxicity testing and in livestock. The present paper is a compilation of these data into a single source to permit comprehensive examination of inter-species variation in rates of hepatic biotransformation. Several substrates were studied for each enzyme system, including cytochrome P-450-dependent monooxygenases, epoxide hydrolases, UDP-glucuronosyltransferases, N-acetyltransferases, glutathione S-transferases and sulfotransferases. The numerous differences in substrate specificity for an individual enzymatic pathway reflect the apparent multiplicity of these enzymes in all 11 species studied. Several hundred- to several thousand-fold differences between species in enzymatic activities for certain substrates under well-defined conditions emphasize the need for caution and the risk of error in extrapolation of xenobiotic metabolism from one species to another. In spite of these uncertainties, knowledge of the rate of biotransformation may help us predict the fate of new chemicals in various species.

  15. Biotransformation of glyceryl trinitrate occurs concurrently with relaxation of rabbit aorta

    SciTech Connect

    Brien, J.F.; McLaughlin, B.E.; Breedon, T.H.; Bennett, B.M.; Nakatsu, K.; Marks, G.S.

    1986-05-01

    This study was conducted to test the hypothesis that biotransformation of glyceryl trinitrate (GTN) is involved in GTN-induced relaxation of vascular smooth muscle. Isolated rabbit aortic strips (RAS) were contracted submaximally with phenylephrine (PE) and then were incubated with 0.5 microM (/sup 14/C)GTN in a time course study. GTN-induced relaxation (inhibition of PE-induced tone) of RAS was monitored and tissue GTN and glyceryl-1,2- and 1,3-dinitrate (GDN) concentrations were measured by thin-layer chromatography and liquid scintillation spectrometry at 0.5, 1, 2 and 20 min after incubation. Biotransformation of GTN to GDN occurred during GTN-induced relaxation of RAS. The tissue GDN concentration was dependent on the time duration of incubation with GTN and was related to the magnitude of GTN-induced tissue relaxation. At the 20-min interval, the GDN concentration in the incubation medium indicated appreciable efflux of GDN metabolites from the RAS. In the biotransformation of GTN by RAS, there was about 4-fold preferential formation of 1,2-GDN compared with 1,3-GDN. RAS were made tolerant to GTN in vitro by incubation with 500 microM GTN for 1 hr. After washing, GTN-tolerant and nontolerant (incubation with vehicle for 1 hr) RAS were contracted submaximally with PE, and then were incubated with 0.5 microM (/sup 14/C)GTN for 2 min. GTN-induced relaxation of RAS and tissue GDN concentration were significantly less for GTN-tolerant tissue compared with nontolerant tissue. Tissue GTN concentration was similar for both GTN-tolerant and nontolerant RAS, which indicated that the tissue uptake of GTN was similar and that GTN biotransformation was diminished in tolerant tissue.(ABST

  16. Characterizing the In Vitro Hepatic Biotransformation of the Flame Retardant BDE 99 by Common Carp

    PubMed Central

    Noyes, Pamela D.; Kelly, Shannon M.; Mitchelmore, Carys L.; Stapleton, Heather M.

    2009-01-01

    Polybrominated diphenyl ethers (PBDEs) are a class of flame retardant chemicals that are known to biomagnify in aquatic foodwebs. However, significant biotransformation of some congeners via reductive dehalogenation has been observed during in vivo and in vitro laboratory exposures, particularly in fish models. Little information is available on the enzyme systems responsible for catalyzing this metabolic pathway in fish. This study was undertaken to characterize the biotransformation of one primary BDE congener, 2,2′,4,4′,5-pentabromodiphenyl ether (BDE-99), using in vitro techniques. Hepatic sub-cellular fractions were first prepared from individual adult common carp (Cyprinus carpio) to examine metabolism in both microsomal and cytosolic sub-cellular fractions. Debromination rates (i.e. BDE-99 biotransformation to BDE-47) were generally higher in the microsomal fraction than in the cytosolic fraction, and some intra-species variability was observed. Further experiments were conducted to determine the biotransformation kinetics and the influence of specific co-factors, inhibitors and competitive substrates on metabolism using pooled carp liver microsomes. The apparent Km and Vmax values were 19.4 μM and 1,120 pmoles hr−1 mg protein−1, respectively. Iodoacetate (IaC) and the two thyroid hormones, reverse triodothyronine (rT3) and thyroxine (T4), significantly inhibited the debromination of BDE-99 in microsomal sub-cellular fractions with IC50 values of 2.2 μM, 0.83 μM, and >1.0 μM, respectively. These results support our hypothesis that deiodinase enzymes may be catalyzing the metabolism of PBDEs in fish liver tissues. Further studies are needed to evaluate metabolic activity in other species and tissues that contain these enzymes. PMID:20080306

  17. 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.

  18. Cytotoxicity, cellular uptake, and cellular biotransformations of oxaliplatin in human colon carcinoma cells.

    PubMed

    Luo, F R; Wyrick, S D; Chaney, S G

    1998-01-01

    Biotransformation products of platinum anticancer drugs have been suggested to be responsible for drug efficacy and toxicity. This study was designed to determine whether the efficacy of the closely related 1,2-diaminocyclohexane-Pt (dach-Pt) compounds oxaliplatin and ormaplatin were determined primarily by the parent drugs or by one of their biotransformation products. Based on consideration of both in vitro cytotoxicity in human colon carcinoma cells (HT-29) and concentrations following oxaliplatin administration in vivo, our data suggest that the efficacy of oxaliplatin is primarily determined by the plasma levels of the parent drug, with the biotransformation products Pt(dach)Cl2, Pt(dach)(H2O)Cl, and Pt(dach)(H2O)2 making only minor contributions. The stable biotransformation products containing amino acids did not have any significant cytotoxicity. In contrast, our data suggest that the efficacy of ormaplatin is primarily determined by plasma levels of Pt(dach)Cl2. The cytotoxicity of oxaliplatin, Pt(dach)Cl2, and Pt(dach)(H2O)Cl was approximately proportional to their cellular uptake, whereas the cytotoxicity of ormaplatin, Pt(dach)(H2O)2, and Pt(dach)(Met) was less than predicted from their uptake. Treatment of HT-29 cells with equimolar external concentrations of Pt(dach)Cl2 and oxaliplatin resulted in the formation of twofold more Pt-DNA adducts following Pt(dach)Cl2 treatment than following oxaliplatin treatment. However, intracellular Pt(dach)Cl2 levels were 30-fold higher for Pt(dach)Cl2-treated cells than for oxaliplatin-treated cells. These data suggest that intracellular conversion of oxaliplatin to Pt(dach)Cl2 makes only a minor contribution to Pt-DNA adduct formation and the resultant cytotoxicity of oxaliplatin. PMID:10367941

  19. 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.

  20. Employment and adolescent alcohol and drug treatment and recovery: an exploratory study.

    PubMed

    Godley, Susan H; Passetti, Lora L; White, Michelle K

    2006-01-01

    Studies of adolescents in the general population show that most high school students are employed and that there is a positive linear relationship between hours worked and increases in alcohol and other drug use. Mixed methods are used to examine the relationship of employment for adolescents who are in outpatient substance abuse treatment to their use, treatment experiences, and recovery. Several theories offered to explain the relationship between adolescent employment and substance use were examined. Most adolescents were employed, often during treatment, with increasing numbers reporting employment over the year-long follow-up period. Adolescents reported frequent alcohol and other drug use after work and with coworkers and indicated that income from work often was used to purchase alcohol and other drugs. Most parents did not provide monitoring of work-related income. Balancing employment and treatment was often logistically difficult and stressful for the adolescents. Employment situations are a critical aspect of adolescents' recovery environment, and more research is needed to learn how to create support for recovery in this aspect of an adolescent's life. PMID:17182430

  1. Role of biotransformation, sorption and mineralization of (14)C-labelled sulfamethoxazole under different redox conditions.

    PubMed

    Alvarino, T; Nastold, P; Suarez, S; Omil, F; Corvini, P F X; Bouju, H

    2016-01-15

    (14)C-sulfamethoxazole biotransformation, sorption and mineralization was studied with heterotrophic and autotrophic biomass under aerobic and anoxic conditions, as well as with anaerobic biomass. The (14)C-radiolabelled residues distribution in the solid, liquid and gas phases was closely monitored along a total incubation time of 190 h. Biotransformation was the main removal mechanism, mineralization and sorption remaining below 5% in all the cases, although the presence of a carbon source exerted a positive effect on the mineralization rate by the aerobic heterotrophic bacteria. In fact, an influence of the type of primary substrate and the redox potential was observed in all cases on the biotransformation and mineralization rates, since an enhancement of the removal rate was observed when an external carbon source was used as a primary substrate under aerobic conditions, while a negligible effect was observed under nitrifying conditions. In the liquid phases collected from all assays, up to three additional peaks corresponding to (14)C-radiolabelled residues were detected. The highest concentration was observed under anaerobic conditions, where two radioactive metabolites were detected representing each around 15% of the total applied radioactivity after 180 h incubation. One of the metabolites detected under anoxic and anaerobic conditions, is probably resulting from ring cleavage of the isoxazole ring. PMID:26546766

  2. 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. PMID:23604533

  3. 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

  4. Pyrene biotransformation and kinetics in the hepatopancreas of the isopod Porcellio scaber.

    PubMed

    Stroomberg, G J; Ariese, F; Gestel, C A M van; Hattum Bv, B van; Velthorst, N H; Straalen, N M van

    2004-10-01

    Various techniques exist for polycyclic aromatic hydrocarbon (PAH) determination in environmental samples, but an adequate risk assessment of PAHs should include aspects such as bioavailability of the contaminant and biotransformation capacity of the species under investigation. In this study, we provided an analysis of the kinetics of pyrene in the terrestrial isopod Porcellio scaber. Isopods were exposed to pyrene in their food (10 microg/g d/w) for 7 days followed by an elimination period of 7 days. The animals were dissected, and the hepatopancreases were analyzed for pyrene biotransformation products; nonmetabolised pyrene in the gut was also monitored. Concentrations of 1-hydroxypyrene in the hepatopancreas were very low. Almost all of the pyrene was found as three conjugates: pyrene-1-glucoside, pyrene-1-sulfate, and a third unknown 1-hydroxypyrene conjugate. Concentrations of the metabolites were extremely variable between individuals because of variable feeding activity. An apparent steady state was reached already after 24 hours of exposure, whereas elimination was complete 48 hours after ending the exposure. This rapid response to changes in the exposure concentration shows that terrestrial isopods have a high biotransformation capacity for PAHs. The data show that concentrations of parent PAHs will not provide a good indication of exposure in rapidly metabolizing invertebrates such as isopods; instead, pyrene metabolites may be considered a promising biomarker for bioavailability of PAH contamination in the field.

  5. 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.

  6. Biotransformation and nitroglycerin-induced effects on antioxidative defense system in rat erythrocytes and reticulocytes.

    PubMed

    Marković, Snežana D; Dorđević, Nataša Z; Curčić, Milena G; Stajn, Andraš S; Spasić, Mihajlo B

    2014-01-01

    The effects of nitroglycerin (glyceryl trinitrate - GTN) are mediated by liberated nitric oxide (NO) and formed reactive nitrogen species, which induces oxidative stress during biotransformation in red blood cells (RBCs). The aim of this study was to evaluate effects of GTN on antioxidative defense system (AOS) in rat erythrocytes (without) and reticulocytes (with functional mitochondria). Rat erythrocyte and reticulocyte-rich RBC suspensions were aerobically incubated (2 h, 37°C) without (control) or in the presence of different concentrations of GTN (0.1-1.5 mM). After incubation, concentrations of non-enzymatic components of AOS, activities of antioxidative enzymes and oxidative pentose phosphate (OPP) pathway activity were followed in RBC suspensions. In rat reticulocytes, GTN decreased the activity of mitochondrial MnSOD and increased the activity of CuZnSOD. In rat RBCs, GTN induced increase of Vit E concentration (at high doses), but decreased glutathione content and activities of all glutathione-dependent antioxidative enzymes; the OPP pathway activity significantly increased. GTN biotransformation and induction of oxidative stress were followed by general disbalance of antioxidative capacities in both kinds of RBCs. We suggest that oxidative stress, MnSOD inhibition and depletion of glutathione pool in response to GTN treatment lead to decreased bioavailability of NO after GTN biotransformation in rat reticulocytes.

  7. 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.

  8. 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. PMID:17061888

  9. 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…

  10. 77 FR 20885 - Agency Information Collection (Vocational Rehabilitation and Employment Longitudinal Study Survey...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-06

    ... AFFAIRS Agency Information Collection (Vocational Rehabilitation and Employment Longitudinal Study Survey.... 2900-New (VR&E Longitudinal Study Survey)'' in any correspondence. For Further Information or a Copy of....mclamb@va.gov . Please refer to ``OMB Control No. 2900-New (VR&E Longitudinal Study...

  11. Biotransformations catalyzed by the genus rhodococcus

    SciTech Connect

    Warhurst, A.M.; Fewson, C.A. . Dept. of Biochemistry)

    1994-01-01

    Rhodococci display a diverse range of metabolic capabilities and they are a ubiquitous feature of many environments. They are able to degrade short-chain, long-chain, and halogenated hydrocarbons, and numerous aromatic compounds, including halogenated and other substituted aromatics, heteroaromatics, hydroaromatics, and polycyclic aromatic hydrocarbons. They possess a wide variety of pathways for degrading and modifying aromatic compounds, including dioxygenase and monooxygenase ring attack, and cleavage of catechol by both ortho- and meta-routes, and some strains posses a modified 3-oxoadipate pathway. Biotransformations catalyzed by rhodococci include steroid modification, enantioselective synthesis, and the transformation of nitriles to amides and acids. Tolerance of rhodococci to starvation, their frequent lack of catabolite repression, and their environmental persistence make them excellent candidates for bioremediation treatments. Some strains can produce poly(3-hydroxyalkanoate)s, others can accumulate cesium, and still others are the source of useful enzymes such as phenylalanine dehydrogenase and endoglycosidases. Other actual or potential applications of rhodococci include desulfurization of coal, bioleaching, use of their surfactants in enhancement of oil recovery and as industrial dispersants, and the construction of biosensors.

  12. 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.

  13. 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

  14. 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

  15. 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.…

  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. 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…

  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. 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…

  1. 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…

  2. 3-Fluorophenmetrazine, a fluorinated analogue of phenmetrazine: Studies on in vivo metabolism in rat and human, in vitro metabolism in human CYP isoenzymes and microbial biotransformation in Pseudomonas Putida and wastewater using GC and LC coupled to (HR)-MS techniques.

    PubMed

    Mardal, Marie; Miserez, Bram; Bade, Richard; Portolés, Tania; Bischoff, Markus; Hernández, Félix; Meyer, Markus R

    2016-09-01

    Wastewater-based epidemiology (WBE) as means to estimate illicit drug and new psychoactive substance (NPS) consumption with spatial and temporal resolution is gaining increasing attention. In order to evaluate a given NPS using WBE, in vivo metabolism and microbial biotransformation of excretion products and unchanged compounds need evaluation. The aims of this study were to identify in vivo phase I and II metabolites of the NPS 3-fluorophenmetrazine (3-FPM) in human and rat urine and study the in vitro contribution of Cytochrome P450 (CYP) isoenzymes in phase I metabolism. Additionally, to study microbial biotransformation products (MBPs) of 3-FPM from incubations in wastewater and in a wastewater isolated Pseudomonas Putida strain. To these aims gas chromatography and liquid chromatography coupled to mass spectrometry were applied. Metabolites and MBPs were isolated from urine and microbial incubations after solid phase extraction and precipitation with or without enzymatic conjungate cleaving. The main transformation pathways were N-oxidation, aryl hydroxylation and subsequent O-methylation, alkyl hydroxylation, oxidation, and degradation of the ethyl-bridge yielding the O/N-bis-dealkylated metabolite, combinations thereof and further glucuronidation or sulfations. The main excretion products in the human urine sample were the unchanged compound and the N-oxide, and the main MBPs were the N-oxide and hydroxylation with subsequent oxidations on the alpha-methyl position. Based on these findings, the proposed strategy for WBE analysis of 3-FPM is quantitative determination of unchanged 3-FPM together with qualitative verification of a number of selected metabolites to verify consumption and rule out discharge. PMID:27372653

  3. 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

  4. Biotransformation of N-nitrosodimethylamine by Pseudomonas mendocina KR1.

    PubMed

    Fournier, Diane; Hawari, Jalal; Streger, Sheryl H; McClay, Kevin; Hatzinger, Paul B

    2006-10-01

    N-Nitrosodimethylamine (NDMA) is a potent carcinogen and an emerging contaminant in groundwater and drinking water. The metabolism of NDMA in mammalian cells has been widely studied, but little information is available concerning the microbial transformation of this compound. The objective of this study was to elucidate the pathway(s) of NDMA biotransformation by Pseudomonas mendocina KR1, a strain that possesses toluene-4-monooxygenase (T4MO). P. mendocina KR1 was observed to initially oxidize NDMA to N-nitrodimethylamine (NTDMA), a novel metabolite. The use of 18O2 and H(2)18O revealed that the oxygen added to NDMA to produce NTDMA was derived from atmospheric O2. Experiments performed with a pseudomonad expressing cloned T4MO confirmed that T4MO catalyzes this initial reaction. The NTDMA produced by P. mendocina KR1 did not accumulate, but rather it was metabolized further to produce N-nitromethylamine (88 to 94% recovery) and a trace amount of formaldehyde (HCHO). Small quantities of methanol (CH3OH) were also detected when the strain was incubated with NDMA but not during incubation with either NTDMA or HCHO. The formation of methanol is hypothesized to occur via a second, minor pathway mediated by an initial alpha-hydroxylation of the nitrosamine. Strain KR1 did not grow on NDMA or mineralize significant quantities of the compound to carbon dioxide, suggesting that the degradation process is cometabolic. PMID:16950909

  5. 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. PMID:23428393

  6. 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.

  7. Enantioselective inhibition of the biotransformation and pharmacological actions of isoidide dinitrate by diphenyleneiodonium sulphate

    PubMed Central

    Ratz, Jodan D; McGuire, John J; Bennett, Brian M

    1999-01-01

    We have shown previously that the D- and L- enantiomers of isoidide dinitrate (D-IIDN and L-IIDN) exhibit a potency difference for relaxation and cyclic GMP accumulation in isolated rat aorta and that this is related to preferential biotransformation of the more potent enantiomer (D-IIDN). The objective of the current study was to examine the effect of the flavoprotein inhibitor, diphenyleneiodonium sulphate (DPI), on the enantioselectivity of IIDN action.In isolated rat aortic strip preparations, exposure to 0.3 μM DPI resulted in a 3.6 fold increase in the EC50 value for D-IIDN-induced relaxation, but had no effect on L-IIDN-induced relaxation.Incubation of aortic strips with 2 μM D- or L-IIDN for 5 min resulted in significantly more D-isoidide mononitrate formed (5.0±1.5 pmol mg  protein−1) than L-isoidide mononitrate (2.1±0.7 pmol mg protein−1) and this difference was abolished by pretreatment of tissues with 0.3 μM DPI. DPI had no effect on glutathione S-transferase (GST) activity or GSH-dependent biotransformation of D- or L-IIDN in the 105,000×g supernatant fraction of rat aorta.Consistent with both the relaxation and biotransformation data, treatment of tissues with 0.3 μM DPI significantly inhibited D-IIDN-induced cyclic GMP accumulation, but had no effect on L-IIDN-induced cyclic GMP accumulation.In the intact animal, 2 mg kg−1 DPI significantly inhibited the pharmacokinetic and haemodynamic properties of D-IIDN, but had no effect L-IIDN.These data suggest that the basis for the potency difference for relaxation by the two enantiomers is preferential biotransformation of D-IIDN to NO, by an enzyme that is inhibited by DPI. Given that DPI binds to and inhibits NADPH-cytochrome P450 reductase, the data are consistent with a role for the cytochromes P450-NADPH-cytochrome P450 reductase system in this enantioselective biotransformation process. PMID:10051121

  8. Two studies of comparative stigma: employer attitudes and practices toward rehabilitated convicts, mental and tuberculosis patients.

    PubMed

    Brand, R C; Clairborn, W L

    1976-01-01

    Two studies compared the effects of stigmatization on two questionnaire measures of social distance and on offers of employment in retail sales. Employers' questionnaire responses revealed less social distance only with tuberculosis patients, compared to exconvicts, exmental patients or marginally adjusted individuals, all of whom did not differ among themselves. There were no differences in the number or conditions of retail sales job offers obtained by six competent experimenters role playing each of three stigmatizing conditions. The results of the studies are seen as reducing concern over the recent changes in California mental health laws which make involuntary commitment in mental hospitals more difficult and may increase the number of convicts who would otherwise become mental patients. Satisfactory employment, often related to low prisoner and mental patient recidivism rates, may be equally accessible to competent exmental patients and felons. PMID:1277781

  9. Biotransformation and bioactivation reactions - 2015 literature highlights.

    PubMed

    Baillie, Thomas A; Dalvie, Deepak; Rietjens, Ivonne M C M; Cyrus Khojasteh, S

    2016-05-01

    Since 1972, Drug Metabolism Reviews has been recognized as one of the principal resources for researchers in pharmacological, pharmaceutical and toxicological fields to keep abreast of advances in drug metabolism science in academia and the pharmaceutical industry. With a distinguished list of authors and editors, the journal covers topics ranging from relatively mature fields, such as cytochrome P450 enzymes, to a variety of emerging fields. We hope to continue this tradition with the current compendium of mini-reviews that highlight novel biotransformation processes that were published during the past year. Each review begins with a summary of the article followed by our comments on novel aspects of the research and their biological implications. This collection of highlights is not intended to be exhaustive, but rather to be illustrative of recent research that provides new insights or approaches that advance the field of drug metabolism. Abbreviations NAPQI N-acetyl-p-benzoquinoneimine ALDH aldehyde dehydrogenase AO aldehyde oxidase AKR aldo-keto reductase CES carboxylesterase CSB cystathionine β-synthase CSE cystathionine γ-lyase P450 cytochrome P450 DHPO 2,3-dihydropyridin-4-one ESI electrospray FMO flavin monooxygenase GSH glutathione GSSG glutathione disulfide ICPMS inductively coupled plasma mass spectrometry i.p. intraperitoneal MDR multidrug-resistant NNAL 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol NNK 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone oaTOF orthogonal acceleration time-of-flight PBK physiologically based kinetic PCP pentachlorophenol SDR short-chain dehydrogenase/reductase SULT sulfotransferase TB tuberculosis. PMID:27362326

  10. Interactions between nutritional factors and drug biotransformations in man.

    PubMed Central

    Alvares, A P; Anderson, K E; Conney, A H; Kappas, A

    1976-01-01

    This study was undertaken to examine the influence of nutritional factors on the activity of the mixed function oxidase system in man, which is cytochrome P-450 dependent. Three normal volunteers were fed a low carbohydrate-high protein diet for 2 weeks, followed by a high carbohydrate-low protein diet for the follwoing 2 weeks. At the end of each test diet period, the plasma elimination rates of antipyrine and theophylline were determined. The mean plasma half-life for antipyrine was 17.5 hr on the high carbohydrate-low protein diet and 9.2 hr on the low carbohydrate-high protein diet. The mean plasma half-life for theophylline was 8.9 hr on the high carbohydrate-low protein diet and 5.9 hr on the low carbohydrate-high protein diet. These data demonstrate marked influences of dietary carbohydrate and/or protein ingestion on oxidative biotransformation of drugs in man. PMID:1065903

  11. [Psychological contract in the light of flexible employment: The review of studies].

    PubMed

    Żołnierczyk-Zreda, Dorota

    2016-01-01

    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. PMID:27623833

  12. 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…

  13. 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…

  14. 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…

  15. 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…

  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. 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…

  18. 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…

  19. 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…

  20. Sharing Career Education Resources with Schools: An Exploratory Study of Employer Willingness.

    ERIC Educational Resources Information Center

    Richards, Edgar L.

    To aid schools planning career education programs, a study (1) identified resources which organizations might be willing to share with schools and (2) attempted to match available resources to easily observable characteristics of employment organizations. Produced through use of the Delphi technique, two lists of variables (organizational…

  1. A Study of Interviewer-Respondent Interaction in the Urban Employment Survey. Final Report.

    ERIC Educational Resources Information Center

    Marquis, Kent H.; Cannell, Charles F.

    The purpose of this study was to provide basic knowledge about the kinds and amounts of behavior in a personal survey interview and to investigate the effects of certain respondent demographic characteristics on the verbal behavior of the interviewer and respondent during the interview. Four sample groups of employed males (Negroes and Caucasians…

  2. 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)

  3. A Study of the Relationship of Overindebtedness and Garnishment to Employability Among Milwaukee WIN Families.

    ERIC Educational Resources Information Center

    Youmans, Rita L.; Miller, Arlene

    This study was designed to ascertain if removal of the threat of garnishment for back debts would increase the employability of WIN enrollees. The pre- and post-WIN debt records of 75 enrollees in Milwaukee WIN were examined intensively during 1969-70. One group of 25 who anticipated garnishment were given financial counseling and granted loans to…

  4. 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…

  5. 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

  6. Music Career Curriculum Development Study: A Study of the Relationship of Curricula to Employment.

    ERIC Educational Resources Information Center

    Wisconsin College-Conservatory, Milwaukee.

    A program to investigate the curriculum available to students in the independent conservatory in terms of future employment is discussed in the document. Three groups of students, from the Wisconsin College-Conservatory, the New England Conservatory, and the San Francisco Conservatory, were interviewed and asked to complete a questionnaire.…

  7. ‘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

  8. EFFECT OF BTEX AND ETHANOL ON ANAEROBIC BIOTRANSFORMATION OF MTBE

    EPA Science Inventory

    We have recently demonstrated that natural anaerobic biotransformation of MTBE to TBA can account for the natural attenuation of MTBE in a plume from a gasoline spill at Parsippany, New Jersey. It is well established in the literature that the presence of the BTEX compounds natu...

  9. 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...

  10. 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...

  11. Proteins differentially expressed during limonene biotransformation by Penicillium digitatum DSM 62840 were examined using iTRAQ labeling coupled with 2D-LC-MS/MS.

    PubMed

    Zhang, Lu-Lu; Zhang, Yan; Ren, Jing-Nan; Liu, Yan-Long; Li, Jia-Jia; Tai, Ya-Nan; Yang, Shu-Zhen; Pan, Si-Yi; Fan, Gang

    2016-10-01

    This study focused on the differences in protein expression at various periods during limonene biotransformation by Penicillium digitatum DSM 62840. A total of 3644 protein-species were quantified by iTRAQ during limonene biotransformation (0 and 12 h). A total of 643 proteins were differentially expressed, 316 proteins were significantly up-regulated and 327 proteins were markedly down-regulated. GO, COG, and pathway enrichment analysis showed that the differentially expressed proteins possessed catalytic and binding functions and were involved in a variety of cellular and metabolic process. Furthermore, the enzymes involved in limonene transformation might be related to cytochrome P-450. This study provided a powerful platform for further exploration of biotransformation, and the identified proteins provided insight into the mechanism of limonene transformation.

  12. 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

  13. 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…

  14. Training and Jobs Programs in Action: Case Studies in Private-Sector Initiatives for the Hard-to-Employ.

    ERIC Educational Resources Information Center

    Robison, David

    This book contains fifty-three case studies covering a wide variety of private-sector activities and public-private partnerships designed to increase training and employment opportunities for the hard-to-employ and speed the transition of the unemployed from government support and subsidized jobs to permanent private employment. Compiled from a…

  15. 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…

  16. Status of Civil Rights in Texas. Volume II: An Employment Profile of San Antonio, 1968-1978. A Case Study.

    ERIC Educational Resources Information Center

    Gerlach, Ernest

    As of 1978 in San Antonio, Texas, equal employment opportunity remained an unfulfilled promise. The Texas Advisory Committee to the U.S. Commission on Civil Rights studied private sector employment in four industries (banking, hospitals, universities, broadcasting), public employment at four governmental levels (municipal, county, state, federal),…

  17. 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

  18. 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

  19. Biotransformation of bisphenol AF to its major glucuronide metabolite reduces estrogenic activity.

    PubMed

    Li, Ming; Yang, Yunjia; Yang, Yi; Yin, Jie; Zhang, Jing; Feng, Yixing; Shao, Bing

    2013-01-01

    Bisphenol AF (BPAF), an endocrine disrupting chemical, can induce estrogenic activity through binding to estrogen receptor (ER). However, the metabolism of BPAF in vivo and the estrogenic activity of its metabolites remain unknown. In the present study, we identified four metabolites including BPAF diglucuronide, BPAF glucuronide (BPAF-G), BPAF glucuronide dehydrated and BPAF sulfate in the urine of Sprague-Dawley (SD) rats. BPAF-G was further characterized by nuclear magnetic resonance (NMR). After treatment with a single dose of BPAF, BPAF was metabolized rapidly to BPAF-G, as detected in the plasma of SD rats. Biotransformation of BPAF to BPAF-G was confirmed with human liver microsomes (HLM), and Vmax of glucuronidation for HLM was 11.6 nmol/min/mg. We also found that BPAF glucuronidation could be mediated through several human recombinant UDP-glucuronosyltransferases (UGTs) including UGT1A1, UGT1A3, UGT1A8, UGT1A9, UGT2B4, UGT2B7, UGT2B15 and UGT2B17, among which UGT2B7 showed the highest efficiency of glucuronidation. To explain the biological function of BPAF biotransformation, the estrogenic activities of BPAF and BPAF-G were evaluated in ER-positive breast cancer T47D and MCF7 cells. BPAF significantly stimulates ER-regulated gene expression and cell proliferation at the dose of 100 nM and 1 μM in breast cancer cells. However, BPAF-G did not show any induction of estrogenic activity at the same dosages, implying that formation of BPAF-G is a potential host defense mechanism against BPAF. Based on our study, biotransformation of BPAF to BPAF-G can eliminate BPAF-induced estrogenic activity, which is therefore considered as reducing the potential threat to human beings. PMID:24349450

  20. 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

  1. Identification of biotransformation products of citalopram formed in activated sludge.

    PubMed

    Beretsou, Vasiliki G; Psoma, Aikaterini K; Gago-Ferrero, Pablo; Aalizadeh, Reza; Fenner, Kathrin; Thomaidis, Nikolaos S

    2016-10-15

    Citalopram (CTR) is a worldwide highly consumed antidepressant which has demonstrated incomplete removal by conventional wastewater treatment. Despite its global ubiquitous presence in different environmental compartments, little is known about its behaviour and transformation processes during wastewater treatment. The present study aims to expand the knowledge on fate and transformation of CTR during the biological treatment process. For this purpose, batch reactors were set up to assess biotic, abiotic and sorption losses of this compound. One of the main objectives of the study was the identification of the formed transformation products (TPs) by applying suspect and non-target strategies based on liquid chromatography quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS). The complementary use of reversed phase liquid chromatography (RPLC) and hydrophilic interaction liquid chromatography (HILIC) for the identification of polar TPs, and the application of in-house developed quantitative structure-retention relationship (QSRR) prediction models, in addition to the comprehensive evaluation of the obtained MS/MS spectra, provided valuable information to support identification. In total, fourteen TPs were detected and thirteen of them were tentatively identified. Four compounds were confirmed (N-desmethylCTR, CTR amide, CTR carboxylic acid and 3-oxo-CTR) through the purchase of the corresponding reference standard. Probable structures based on diagnostic evidence were proposed for the additional nine TPs. Eleven TPs are reported for the first time. A transformation pathway for the biotransformation of CTR was proposed. The presence of the identified TPs was assessed in real wastewater samples through retrospective analysis, resulting in the detection of five compounds. Finally, the potential ecotoxicological risk posed by CTR and its TPs to different trophic levels of aquatic organisms was evaluated by means of risk quotients. PMID:27459150

  2. 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. PMID:25705913

  3. 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.

  4. 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. PMID:25089706

  5. 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

  6. 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.

  7. 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.

  8. 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

  9. 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. PMID:27373739

  10. Xenobiotic and steroid biotransformation activities in rainbow trout gill epithelial cells in culture.

    PubMed

    Leguen; Carlsson; Perdu-Durand; Prunet; Pärt; Cravedi

    2000-03-01

    The biotransformation of xenobiotics and steroids was investigated in cultured respiratory epithelial cells from rainbow trout (Oncorhynchus mykiss) gills. As a first approach, ethoxyresorufin-O-deethylase (EROD), chosen as a marker of CYP1A activity, was measured in monolayers of adherent cells. The induction of this enzyme was studied in cells exposed to beta-naphthoflavone (BNF) or 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in concentrations ranging from 10(-6) to 10(-12) M. After 24 h, TCDD showed a maximal induction at a concentration of 10(-9) M while BNF showed a maximal induction at a concentration of 10(-7) M. Concurrently, a variety of substrates involved in cytochrome P450-dependent metabolism as well as phase II reactions, namely ethoxycoumarin, aniline and testosterone were incubated with cultured gill cells for 2 or 8 h and with freshly isolated hepatocytes for comparison. Our results revealed a significant cytochrome P450-dependent activity in gill cells with ethoxycoumarin and aniline, but no hydroxylation was observed with testosterone as substrate. No trace of sulfate conjugate was detected. With 2.5 µM aniline as substrate, 2-hydroxyaniline accounted for 32.1% of the radioactivity after 2 h incubation whereas acetanilide amounted to 6.4%. Significant differences were found between gill cells and isolated hepatocytes in the capacity of these systems to conduct oxidative and conjugating metabolic pathways. Qualitatively, the main difference was observed for testosterone which is hydroxylated in position 6beta and 16beta and conjugated to glucuronic acid in liver cells, whereas reductive biotransformation giving rise to dihydrotestosterone and androstanediol and traces of androstenedione were observed in gill cells. Quantitatively, the biotransformation activity in gill epithelial cells, expressed as pmol/h per mg protein, was between 1.5 and 14% of the activity level observed in isolated hepatocytes, depending on the substrate.

  11. Isolation and structural elucidation of biotransformation products from acarbose.

    PubMed

    Boberg, M; Kurz, J; Ploschke, H J; Schmitt, P; Scholl, H; Schüller, M; Wünsche, C

    1990-05-01

    Following oral administration the a-glucosidase inhibitor acarbose (O-4,6-dideoxy-4-[[(1S,4R,5S,6S)-4,5,6-trihydroxy-3-(hydroxymethyl) -2-cyclohexen-1-yl]amino]-a-D-glucopyranosyl-(1----4)-O-a-D-glu copyranosyl-(1----4)-D-glucopyranose, Bay g 5421) is degraded by digestive enzymes and/or intestinal microorganism. The effect of anaerobic intestinal bacteria can be studied in an in vitro model which involves the incubation of acarbose with human or animal intestinal flora. Acarbose and nine biotransformation products can be isolated from the incubation mixture. These products were identified by nuclear magnetic resonance and mass spectrometry as so-called component 2 (loss of the terminal glucose), component 1 (loss of both glucose rings), hexose homologues of acarbose and component 2, methyl homologues of acarbose, butyric acid ester of component 2, basic disaccharide (loss of the cyclitol ring of component 2), delta-aminovaleric acid and gamma-aminobutyric acid. Following oral administration of [14C]-acarbose to healthy volunteers, 35% of the radioactivity was excreted in the form of at least 13 metabolites in the urine. Three of the metabolites were isolated by Craig countercurrent distribution and ion-pair HPLC and characterized by virtue of their nuclear magnetic resonance and mass spectra as derivatives of 4-methylpyrogallol. Two were shown to be monomethylether-monosulphates while the third was a monosulphate-monoglucuronide. The synthesis of ten reference substances and the comparison of HPLC and UV data clearly indicated that the majority of the non-isolated metabolites were also 4-methylpyrogallol derivatives. The peculiarities of the nuclear magnetic resonance and mass spectra of this type of compound are discussed.

  12. Preparing Youth for Employment.

    ERIC Educational Resources Information Center

    Bishop, John

    A four-year study examined the nature and policy implications of school and employer practices to help youth prepare for employment. Data for the study were compiled from a telephone survey of 3,500 employers; a mail survey of 750 employers from across the country; 493 employers, 71 teachers, and 1,565 students from 5 major U.S. cities who…

  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. 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…

  15. 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…

  16. 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. PMID:25189516

  17. Biotransformation of polyphenols in a dynamic multistage gastrointestinal model.

    PubMed

    Sadeghi Ekbatan, Shima; Sleno, Lekha; Sabally, Kebba; Khairallah, Joelle; Azadi, Behnam; Rodes, Laetitia; Prakash, Satya; Donnelly, Danielle J; Kubow, Stan

    2016-08-01

    A multi-reactor gastrointestinal model was used to digest a mixture of pure polyphenol compounds, including non-flavonoid phenolic acids (chlorogenic acid, caffeic acid, ferulic acid) and a flavonoid (rutin) to identify phenolic metabolites and short chain fatty acids (SCFAs) and compare relative antioxidant capacities following a 24h digestion. Biotransformation of these polyphenols occurred in the colonic compartments generating phenylpropionic, benzoic, phenylacetic and cinnamic acids. Total SCFAs increased in all colonic vessels with a rise in the proportion of propionic to acetic acid. Antioxidant capacity increased significantly in all compartments, but first in the stomach, small intestine and ascending colon. After 24h, the colonic vessels without parent polyphenols, but containing new metabolites, had antioxidant capacities similar to the stomach and small intestine, containing parent compounds. Biotransformation of pure polyphenols resulted in different phenolic metabolite and SCFAs profiles in each colonic segment, with important health implications for these colonic compartments. PMID:26988524

  18. Long term biotransformation and toxicity of dimercaptosuccinic acid-coated magnetic nanoparticles support their use in biomedical applications.

    PubMed

    Mejías, Raquel; Gutiérrez, Lucía; Salas, Gorka; Pérez-Yagüe, Sonia; Zotes, Teresa M; Lázaro, Francisco J; Morales, María P; Barber, Domingo F

    2013-10-28

    Although iron oxide magnetic nanoparticles (MNP) have been proposed for numerous biomedical applications, little is known about their biotransformation and long-term toxicity in the body. Dimercaptosuccinic acid (DMSA)-coated magnetic nanoparticles have been proven efficient for in vivo drug delivery, but these results must nonetheless be sustained by comprehensive studies of long-term distribution, degradation and toxicity. We studied DMSA-coated magnetic nanoparticle effects in vitro on NCTC 1469 non-parenchymal hepatocytes, and analyzed their biodistribution and biotransformation in vivo in C57BL/6 mice. Our results indicate that DMSA-coated magnetic nanoparticles have little effect on cell viability, oxidative stress, cell cycle or apoptosis on NCTC 1469 cells in vitro. In vivo distribution and transformation were studied by alternating current magnetic susceptibility measurements, a technique that permits distinction of MNP from other iron species. Our results show that DMSA-coated MNP accumulate in spleen, liver and lung tissues for extended periods of time, in which nanoparticles undergo a process of conversion from superparamagnetic iron oxide nanoparticles to other non-superparamagnetic iron forms, with no significant signs of toxicity. This work provides the first evidence of DMSA-coated magnetite nanoparticle biotransformation in vivo.

  19. 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.

  20. 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.

  1. 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. PMID:16272725

  2. 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…

  3. The Value of the Distance Teaching University Degrees in the Employment Market: A Study of the Fernuniversitat Graduates.

    ERIC Educational Resources Information Center

    Bartels, Jorn; Rathore, Harish C. S.

    1989-01-01

    Describes a study that was conducted to examine the perceptions of the graduates of FernUniversitat about the acceptance of their distance education degrees by themselves, their employers, their colleagues, and academics at conventional universities; and to study their perceptions of the value of their degrees in the employment market. (LRW)

  4. 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.…

  5. 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.

  6. 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.

  7. 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. PMID:26692509

  8. 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.).

  9. Biotransformation: a green and efficient way of antioxidant synthesis.

    PubMed

    Zafar, Salman; Ahmed, Rida; Khan, Rasool

    2016-09-01

    Antioxidant compounds play a vital role in human physiology. They prevent the oxidation of biomolecules by scavenging free radicals produced during physiochemical processes and/or as a result of several pathological states. A balance between the reactive oxygen species (free radicals) and antioxidants is essential for proper physiological conditions. Excessive free radicals cause oxidative stress which can lead to several human diseases. Therefore, synthesis of the effective antioxidants is crucial in managing the oxidative stress. Biotransformation has evolved as an effective technique for the production of structurally diverse molecules with a wide range of biological activities. This methodology surpasses the conventional chemical synthesis due to the fact that enzymes, being specific in nature, catalyze reactions affording products with excellent regio- and stereoselectivities. Structural transformation of various classes of compounds such as alkaloids, steroids, flavonoids, and terpenes has been carried out through this technique. Several bioactive molecules, especially those having antioxidant potential have also been synthesized by using different biotransformation techniques and enzymes. Hydroxylated, glycosylated, and acylated derivatives of phenols, flavonoids, cinnamates, and other molecules have proven abilities as potential antioxidants. A critical review of the biotransformation of these compounds into potent antioxidant metabolites is presented here. PMID:27383446

  10. 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

  11. 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.

  12. Micropollutant biotransformation kinetics associate with WWTP process parameters and microbial community characteristics.

    PubMed

    Helbling, Damian E; Johnson, David R; Honti, Mark; Fenner, Kathrin

    2012-10-01

    The objective of this work was to identify relevant wastewater treatment plant (WWTP) parameters and underlying microbial processes that influence the biotransformation of a diverse set of micropollutants. To do this, we determined biotransformation rate constants for ten organic micropollutants in batch reactors seeded with activated sludge from ten diverse WWTPs. The estimated biotransformation rate constants for each compound ranged between one and four orders of magnitude among the ten WWTPs. The biotransformation rate constants were tested for statistical associations with various WWTP process parameters, amoA transcript abundance, and acetylene-inhibited monooxygenase activity. We determined that (i) ammonia removal associates with oxidative micropollutant biotransformation reaction rates; (ii) archaeal but not bacterial amoA transcripts associate with both ammonia removal and oxidative micropollutant biotransformation reaction rates; and (iii) the activity of acetylene-inhibited monooxygenases (including ammonia monooxygenase) associates with ammonia removal and the biotransformation rate of isoproturon, but does not associate with all oxidative micropollutant biotransformations. In combination, these results lead to the conclusion that ammonia removal and amoA transcript abundance can potentially be predictors of oxidative micropollutant biotransformation reactions, but that the biochemical mechanism is not necessarily linked to ammonia monooxygenase activity. PMID:22938719

  13. 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…

  14. 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)

  15. Use of cyclodextrins in biotransformation reactions with cell cultures of Morus nigra: biosynthesis of prenylated chalcone isocordoin.

    PubMed

    Bolasco, Adriana; Fioravanti, Rossella; Rossi, Francesca; Rossi, Paola; Vitali, Alberto

    2010-06-16

    In vivo biotransformation experiments were performed by using a cell suspension culture of Morus nigra expressing a high PT (prenyltransferase) activity, fed with the target substrate 2',4'-dihydroxychalcone. In order to improve the reaction yields by enhancing the chalcone solubility, three different cyclodextrins have been used to host the substrate. The respective complexes have been studied by means of both spectroscopic and calorimetric techniques (Fourier-transform infrared, 1H-NMR and differential scanning calorimetry) and the solution behaviours have been characterized by solubility phase studies. The hydroxypropyl-beta-cyclodextrin complex was found to be the most suitable for biotransformation, and the reaction of prenylation resulted in a 6-fold higher yield of the final product when compared with the use of the free substrate. The reaction provided as the sole product the 3'-dimethylallyl derivative isocordoin, a biologically active plant compound. The results obtained allow the development of systems based on the use of biofermentors or the use of immobilized cells in order to enhance the biotransformation yields.

  16. HPLC analysis of midodrine and desglymidodrine in culture medium: evaluation of static and shaken conditions on the biotransformation by fungi.

    PubMed

    Barth, Thiago; Aleu, Josefina; Pupo, Mônica Tallarico; Bonato, Pierina Sueli; Collado, Isidro G

    2013-01-01

    A high-performance liquid chromatography (HPLC) method is presented for the simultaneous determination of midodrine and desglymidodrine (DMAE) in Czapek-Dox culture medium, to be used in biotransformation studies by fungi. The HPLC analysis was conducted using a Lichrospher 100 RP18 column, acetonitrile-40 mmol/L formic acid solution (60:40, v/v) as mobile phase, and ultraviolet detection at 290 nm. The sample preparation was conducted by liquid-liquid extraction using ethyl acetate as extractor solvent. The method was linear over the concentration range of 0.4-40.0 µg/mL for midodrine (r ≥ 0.9997) and DMAE (r ≥ 0.9998). Within-day and between-day precision and accuracy were evaluated by relative standard deviations (≤ 8.2%) and relative errors (-7.3 to 7.4%), respectively. The validated method was used to assess midodrine biotransformation by the fungi Papulaspora immersa Hotson SS13, Botrytis cinerea UCA 992 and Botrytis cinerea 2100 under static and shaken conditions. Under shaken conditions, the biotransformation of midodrine to DMAE was more efficient for all studied fungi, especially for the fungus Botrytis cinerea 2100, which converted 42.2% of midodrine to DMAE.

  17. Insurer and Employer Views on Pediatric Obesity Treatment: a Qualitative Study

    PubMed Central

    Hampl, S.E.; Davis, A.M.; Sampilo, M.L.; Stephens, K.L.; Dean, K.

    2014-01-01

    Objective The effectiveness of group-based comprehensive, multidisciplinary (stage 3) pediatric weight management programs is backed by a growing body of literature, yet insurance coverage of these programs is scarce to nonexistent, limiting their reach and long-term survival. The objective of this study was to better understand the perspectives of insurers and large employers on the issue of group-based treatment coverage. Design and Methods The authors performed a qualitative study utilizing structured interviews with these stakeholders, following accepted techniques. Results Six major themes emerged: cost, program effectiveness, corporate social responsibility, secondary parental (employee) benefits, coverage options and new benefit determination. Conclusion Future efforts to secure payment for group-based pediatric weight management programs should address these key themes. PMID:23712982

  18. Frequency-modulated light scattering interferometry employed for optical properties and dynamics studies of turbid media

    PubMed Central

    Mei, Liang; Somesfalean, Gabriel; Svanberg, Sune

    2014-01-01

    In the present work, fiber-based frequency-modulated light scattering interferometry (FMLSI) is developed and employed for studies of optical properties and dynamics in liquid phantoms made from Intralipid®. The fiber-based FMLSI system retrieves the optical properties by examining the intensity fluctuations through the turbid medium in a heterodyne detection scheme using a continuous-wave frequency-modulated coherent light source. A time resolution of 21 ps is obtained, and the experimental results for the diluted Intralipid phantoms show good agreement with the predicted results based on published data. The present system shows great potential for assessment of optical properties as well as dynamic studies in liquid phantoms, dairy products, and human tissues. PMID:25136504

  19. A Multilevel Study of Students' Motivations of Studying Accounting: Implications for Employers

    ERIC Educational Resources Information Center

    Law, Philip; Yuen, Desmond

    2012-01-01

    Purpose: The purpose of this study is to examine the influence of factors affecting students' choice of accounting as a study major in Hong Kong. Design/methodology/approach: Multinomial logistic regression and Hierarchical Generalized Linear Modeling (HGLM) are used to analyze the survey data for the level one and level two data, which is the…

  20. Arsenic biotransformation by cyanobacteria from mining areas: evidences from culture experiments.

    PubMed

    Franco, Maione W; Ferreira, Fernanda A G; Vasconcelos, Igor F; Batista, Bruno L; Pujoni, Diego G F; Magalhães, Sérgia M S; Barbosa, Fernando; Barbosa, Francisco A R

    2015-12-01

    Elucidating the role of cyanobacteria in the biotransformation of arsenic (As) oxyanions is crucial to understand the biogeochemical cycle of this element and indicate species with potential for its bioremediation. In this study, we determined the EC50 for As(III) and As(V) and evaluated the biotransformation of As by Synechococcus sp. through high-performance liquid chromatography hyphenated to inductively coupled plasma mass spectrometry (HPLC-ICP-MS) and X-ray absorption fine structure spectroscopy (XAFS). Synechococcus sp. exhibited higher sensitivity to As(III) with an EC(50, 96 h) of 6.64 mg L(-1) that was approximately 400-fold lower than that for As(V). Even though the cells were exposed to concentrations of As(III) (6 mg L(-1)) approximately 67-fold lower than those of As(V) (400 mg L(-1)), similar intracellular concentrations of As (60.0 μg g(-1)) were observed after 30 days. As(V) was the predominant intracellular As species followed by As(III). Furthermore, organic As species such as monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA) were observed in higher proportions after exposure to As(III). The differential toxicity among As oxyanions indicates that determining the redox state of As in the environment is fundamental to estimate toxicity risks to aquatic organisms. Synechococcus sp. demonstrated potential for its application in bioremediation due to the high accumulation of As and production of As organic compounds notably after exposure to As(III).

  1. Biotransformation of dehydro-epi-androsterone by Aspergillus parasiticus: Metabolic evidences of BVMO activity.

    PubMed

    Mascotti, M Laura; Palazzolo, Martín A; Bisogno, Fabricio R; Kurina-Sanz, Marcela

    2016-05-01

    The research on the synthesis of steroids and its derivatives is of high interest due to their clinical applications. A particular focus is given to molecules bearing a D-ring lactone like testolactone because of its bioactivity. The Aspergillus genus has been used to perform steroid biotransformations since it offers a toolbox of redox enzymes. In this work, the use of growing cells of Aspergillus parasiticus to study the bioconversion of dehydro-epi-androsterone (DHEA) is described, emphasizing the metabolic steps leading to D-ring lactonization products. It was observed that A. parasiticus is not only capable of transforming bicyclo[3.2.0]hept-2-en-6-one, the standard Baeyer-Villiger monooxygenase (BVMO) substrate, but also yielded testololactone and the homo-lactone 3β-hydroxy-17a-oxa-D-homoandrost-5-en-17-one from DHEA. Moreover, the biocatalyst degraded the lateral chain of cortisone by an oxidative route suggesting the action of a BVMO, thus providing enough metabolic evidences denoting the presence of BVMO activity in A. parasiticus. Furthermore, since excellent biotransformation rates were observed, A. parasiticus is a promising candidate for the production of bioactive lactone-based compounds of steroidal origin in larger scales. PMID:27025973

  2. Biotransformation of 17α-methyltestosterone in sediment under different electron acceptor conditions.

    PubMed

    Homklin, Supreeda; Ong, Say Kee; Limpiyakorn, Tawan

    2011-03-01

    17α-Methyltestosterone (MT), an anabolic androgenic steroid, is used widely in inducing an all male population in aquaculture farming of fish, such as Nile tilapia (Oreochromis niloticus). Current understanding of the occurrence and fate of MT in the sediments and the surrounding areas of the aquaculture ponds are very limited. Bioassay tests showed that MT was biotransformed under aerobic and sulfate-reducing conditions with a half-life of 3.8d and 5.3d, respectively, with complete disappearance of androgenic activity. However, under methanogenic condition, MT was found to biotransform but the androgenic activity continued to persist even after 45 d of incubation. In contrast, MT was found to transform slowly under iron(III)-reducing condition and was hardly transformed under nitrate-reducing condition. A possible reason for the lack of transformation of MT under nitrate-reducing condition is the presence of the methyl group at the C-17 position. The results of this study suggest that MT and its degradation products with androgenic activity may potentially accumulate in the sediments of fish farming ponds under iron(III)-reducing, nitrate-reducing and methanogenic conditions.

  3. Effects of beta-naphthoflavone on hepatic biotransformation and glutathione biosynthesis in largemouth bass (Micropterus salmoides).

    PubMed

    Hughes, Erin M; Gallagher, Evan P

    2004-01-01

    We are investigating the effects of in vivo exposure of prototypical enzyme inducing agents on hepatic biotransformation enzyme expression in largemouth bass (Micropterus salmoides), a predatory game fish found throughout the United States and Canada. The current study targeted those genes involved in biotransformation and oxidative stress that may be regulated by Ah-receptor-dependent pathways. Exposure of bass to beta-naphthoflavone (beta-NF, 66 mg/kg, i.p.) elicited a 7-9-fold increase in hepatic microsomal cytochrome P4501A-dependent ethoxyresorufin O-deethylase (EROD) activities, but did not affect cytosolic GST catalytic activities toward 1-chloro-2,4-dinitrobenzene (CDNB) or 5-androstene-3,17-dione (ADI). Glutathione S-transferase A (GST-A) mRNA expression exhibited a transient, but non-significant increase following exposure to beta-NF, and generally tracked the minimal changes observed in GST-CDNB activities. Expression of the mRNA encoding glutamate-cysteine ligase catalytic subunit (GCLC), the rate-limiting enzyme in glutathione (GSH) biosynthesis, was increased 1.7-fold by beta-NF. Changes in GCLC mRNA expression were paralleled by increases in intracellular GSH. In summary, largemouth bass hepatic CYP1A-dependent and GSH biosynthetic pathways, and to a lesser extent GST, are responsive to exposure to beta-NF.

  4. Identification of intermediate and branch metabolites resulting from biotransformation of 2-benzoxazolinone by Fusarium verticillioides.

    PubMed

    Glenn, A E; Meredith, F I; Morrison, W H; Bacon, C W

    2003-06-01

    Detoxification of the maize (Zea mays) antimicrobial compound 2-benzoxazolinone by the fungal endophyte Fusarium verticillioides involves two genetic loci, FDB1 and FDB2, and results in the formation of N-(2-hydroxyphenyl)malonamic acid. Intermediate and branch metabolites were previously suggested to be part of the biotransformation pathway. Evidence is presented here in support of 2-aminophenol as the intermediate metabolite and 2-acetamidophenol as the branch metabolite, which was previously designated as BOA-X. Overall, 2-benzoxazolinone metabolism involves hydrolysis (FDB1) to produce 2-aminophenol, which is then modified (FDB2) by addition of a malonyl group to produce N-(2-hydroxyphenyl)malonamic acid. If the modification is prevented due to genetic mutation (fbd2), then 2-acetamidophenol may accumulate as a result of addition of an acetyl group to 2-aminophenol. This study resolves the overall chemistry of the 2-benzoxazolinone detoxification pathway, and we hypothesize that biotransformation of the related antimicrobial 6-methoxy-2-benzoxazolinone to produce N-(2-hydroxy-4-methoxyphenyl)malonamic acid also occurs via the same enzymatic modifications. Detoxification of these antimicrobials by F. verticillioides apparently is not a major virulence factor but may enhance the ecological fitness of the fungus during colonization of maize stubble and field debris.

  5. Atropa belladonna hairy roots: orchestration of concurrent oxidation and reduction reactions for biotransformation of carbonyl compounds.

    PubMed

    Srivastava, Vikas; Negi, Arvind Singh; Ajayakumar, P V; Khan, Shamshad A; Banerjee, Suchitra

    2012-03-01

    The biotransformation potential of a selected Atropa belladonna hairy root clone (AB-09) had been evaluated with regard to three different aromatic carbonyl compounds, i.e., 3,4,5-trimethoxybenzaldehyde (1), 3,4,5-trimethoxyacetophenone (2), and 3,4,5-trimethoxy benzoic acid (3). The results demonstrated for the first time the untapped potentials of the selected hairy root clone to perform simultaneous oxidation (34.49%) and reduction (32.68%) of 3,4,5-trimethoxy benzaldehyde (1) into 3,4,5-trimethoxy benzoic acid (3), and 3,4,5-trimethoxy benzyl alcohol (4), respectively, without any intermediate separation or addition of reagents. The same hairy root clone also demonstrated reduction (<5%) of a 3,4,5-trimethoxyacetophenone (2) into a secondary alcohol, i.e., 1-(3,4,5-trimethoxyphenyl) ethanol (5), while in the case of aromatic carboxylic acid substrate (3), no biotransformation could be obtained under the similar conditions. The current observations revealed oxidation and reduction of the formyl group of the aromatic ring, and only reduction of the carbonyl group of acetophenone through the specific hairy root clone. The concurrent oxidation and reduction reactions by the selected hairy root clone highlight the importance of this study, which, as per our observations, is the first of its kind relating the hairy root culture of A. belladonna.

  6. Comparative Oral Bioavailability, Toxicokinetics, and Biotransformation of Enniatin B1 and Enniatin B in Broiler Chickens.

    PubMed

    Fraeyman, Sophie; Devreese, Mathias; Antonissen, Gunther; De Baere, Siegrid; Rychlik, Michael; Croubels, Siska

    2016-09-28

    A toxicokinetic study of the Fusarium mycotoxins enniatin B1 (ENN B1) and enniatin B (ENN B) was performed in broiler chickens. Each animal received ENN B1 or B orally via an intracrop bolus and intravenously at a dose of 0.2 mg/kg body weight. Both enniatins were poorly absorbed after oral administration, with absolute oral bioavailabilities of 0.05 and 0.11 for ENNs B1 and B, respectively. Both enniatins were readily distributed to the tissues, with mean volumes of distribution of 25.09 and 33.91 L/kg for ENNs B1 and B, respectively. The mean total body clearance was rather high, namely, 6.63 and 7.10 L/h/kg for ENNs B1 and B, respectively. Finally, an UHPLC-HRMS targeted approach was used to investigate the phase I and II biotransformations of both mycotoxins. Oxygenation was the major phase I biotransformation pathway for both ENNs B1 and B. Neither glucuronide nor sulfate phase II metabolites were detected. PMID:27632250

  7. Modeling bioaccumulation and biotransformation of PAHs and PCBs by benthic macrofauna from lower Chesapeake Bay

    SciTech Connect

    Dickhut, R.M.; Schaffner, L.C.; Lay, P.; Mitra, S.

    1995-12-31

    The bioaccumulation and biotransformation of selected PAHs and PCBs from sediments spiked with radiolabeled compounds were examined in benthic communities from lower chesapeake Bay during summer and winter. Kinetic models were then used to determine the steady-state bioaccumulation factors (BAFs) for the parent compounds in various benthic macrofaunal organisms, as well as the BAFs of aqueous soluble metabolites that tended to accumulate in the animals. BAFs for the parent compounds increased with the octanol-water partition coefficient (K{sub ow}) of the compound up to a log K{sub ow} of approximately 6. However, in contrast to previous studies, the elimination rate constant was the dominant factor controlling the observed nonequilibrium with respect to bioaccumulation of the organic contaminants. Consequently, BAFs for the parent contaminants were related to the physical-chemical factors regulating passive elimination, as well as metabolic transformation of the parent compound. Aqueous soluble metabolite BAFs were directly related to the physical-chemical factors dictating the rate of formation of the conjugated complexes. Overall, body burdens of organic contaminants were higher in the summer relative to winter, as were the aqueous soluble metabolite fractions of contaminants in the animals, possibly indicating that organism activities as well as lipid pools are higher in summer compared to winter. The results indicate that a variety of physical, chemical, and biological factors interact in the ecosystem to dictate bioaccumulation and biotransformation of organic contaminants.

  8. Biotransformation of the flame retardant tetrabromobisphenol-A (TBBPA) by freshwater microalgae.

    PubMed

    Peng, Fu-Qiang; Ying, Guang-Guo; Yang, Bin; Liu, You-Sheng; Lai, Hua-Jie; Zhou, Guang-Jie; Chen, Jun; Zhao, Jian-Liang

    2014-08-01

    Tetrabromobisphenol-A (TBBPA) is the most widely used brominated flame retardant. However, little is known about its biotransformation by algae in aquatic environments. The authors investigated transformations of TBBPA by 6 freshwater green microalgae and identified its transformation products. Transformation experiments were conducted under axenic conditions in a laboratory for 10 d. The results showed that TBBPA could be transformed by the selected microalgae, with nearly complete removal by Scenedesmus quadricauda and Coelastrum sphaericum following 10-d incubation. Five transformation products were positively identified by mass spectrometry: TBBPA sulfate, TBBPA glucoside, sulfated TBBPA glucoside, TBBPA monomethyl ether, and tribromobisphenol-A. The mechanisms involved in the biotransformation of TBBPA include sulfation, glucosylation, O-methylation, and debromination, which could be an important step for its further degradation. This suggests that microalgae can play an important role in the fate of TBBPA in aquatic environments. The present study is the first report on algal transformation of TBBPA, and the proposed transformation products could have significant environmental implications. PMID:24687216

  9. Effect of pine bark on the biotransformation of trinitrotoluene and on the bacterial community structure in a batch experiment.

    PubMed

    Chusova, Olga; Nolvak, Hiie; Nehrenheim, Emma; Truu, Jaak; Odlare, Monica; Oopkaup, Kristjan; Truu, Marika

    2014-01-01

    Pine bark, a low-cost industrial residue, has been suggested as a promising substitute for granular activated carbon in the on-site treatment of water contaminated with 2,4,6-trinitrotoluene (TNT). However, the complex organic structure and indigenous microbial community of pine bark have thus far not been thoroughly described in the context of TNT-contaminated water treatment. This two-week batch study examined the removal efficiency ofTNT from water by (1) adsorption on pine bark and (2) simultaneous adsorption on pine bark and biotransformation by specialized TNT-biotransforming microbial inocula. The bacterial community composition of experimental batches, inocula and pine bark, was profiled by Illumina sequencing of the V6 region of the 16S rRNA gene. The results revealed that the inocula and experimental batches were dominated by phylotypes belonging to the Enterobacteriaceae family and that the tested inocula had good potential for TNT biotransformation. The type of applied inocula had the most profound effect on the TNT-transforming bacterial community structure in the experimental batches. The indigenous microbial community of pine bark harboured phylotypes that also have a potential to degrade TNT. Altogether, the combination of a specialized inoculum and pine bark proved to be the most efficient treatment option for TNT-contaminated water. PMID:25145200

  10. Effect of pine bark on the biotransformation of trinitrotoluene and on the bacterial community structure in a batch experiment.

    PubMed

    Chusova, Olga; Nolvak, Hiie; Nehrenheim, Emma; Truu, Jaak; Odlare, Monica; Oopkaup, Kristjan; Truu, Marika

    2014-01-01

    Pine bark, a low-cost industrial residue, has been suggested as a promising substitute for granular activated carbon in the on-site treatment of water contaminated with 2,4,6-trinitrotoluene (TNT). However, the complex organic structure and indigenous microbial community of pine bark have thus far not been thoroughly described in the context of TNT-contaminated water treatment. This two-week batch study examined the removal efficiency ofTNT from water by (1) adsorption on pine bark and (2) simultaneous adsorption on pine bark and biotransformation by specialized TNT-biotransforming microbial inocula. The bacterial community composition of experimental batches, inocula and pine bark, was profiled by Illumina sequencing of the V6 region of the 16S rRNA gene. The results revealed that the inocula and experimental batches were dominated by phylotypes belonging to the Enterobacteriaceae family and that the tested inocula had good potential for TNT biotransformation. The type of applied inocula had the most profound effect on the TNT-transforming bacterial community structure in the experimental batches. The indigenous microbial community of pine bark harboured phylotypes that also have a potential to degrade TNT. Altogether, the combination of a specialized inoculum and pine bark proved to be the most efficient treatment option for TNT-contaminated water.

  11. Biotransformation of organic-rich copper-bearing black shale by indigenous microorganisms isolated from lubin copper mine (Poland).

    PubMed

    Matlakowska, Renata; Narkiewicz, Wanda; Sklodowska, Aleksandra

    2010-04-01

    The role of indigenous microorganisms in the biotransformation of refractory organic-rich copper-bearing black shale ore (Kupferschiefer) was confirmed in laboratory experiments. The persistent shale's organic matter was utilized by a mixture of bacterial strains as the sole carbon and energy source, and bacterial growth was accompanied by chemical and structural changes of black shale. The release of metallic elements and organic compounds into the aqueous phase was shown. Chemical analysis revealed the presence of long-chain aliphatic hydrocarbons and further biodegradation of these compounds by bacterial action. In this study, the release of metals from metalloorganic compounds present in organic-rich copper-bearing black shale was shown for the first time. The results have also confirmed the biotransformation of metalloporphyrins naturally occurring in black shale by indigenous microorganisms. Moreover, changes in the surface area and quantitative mineral composition of black shale were detected following bacterial treatment. This biotransformation activity is of potential use in biotechnological procedures for the recovery of copper and other valuable metals from tailings that contain up to 16% black shale. On the other hand, the release of organic carbon and heavy metals from black shale by biodegradation may significantly add to anthropogenic pollution.

  12. Mental Health Improves after Transition from Comprehensive School to Vocational Education or Employment in England: A National Cohort Study

    ERIC Educational Resources Information Center

    Symonds, Jennifer; Dietrich, Julia; Chow, Angela; Salmela-Aro, Katariina

    2016-01-01

    Underpinned by stage-environment fit and job demands-resources theories, this study examined how adolescents' anxiety, depressive symptoms, and positive functioning developed as they transferred from comprehensive school to further education, employment or training, or became NEET (not in education, employment, or training), at age 16 years, in…

  13. A Descriptive Study on the Relationship between an Initial Physical Education Teacher Education Program and Employment Longevity

    ERIC Educational Resources Information Center

    Bebie, Kerry A.

    2012-01-01

    The purposes of this descriptive study were to better describe to the administrators of a Midwestern university the strengths and weaknesses of its physical education program, to furnish a description of the alumni with respect to employment longevity in the field of physical education, employment trends, and attitudes toward the program. The…

  14. A Study of Employment Demand for Agriculture and Agribusiness in New York State. Phase I Final Report.

    ERIC Educational Resources Information Center

    Berkey, Arthur L.; And Others

    Phase 1 of a two-phase study on employment demand in Agriculture/Agribusiness for New York State focused on data collection. Four objectives were to (1) compile a preliminary listing of current occupations by industry emphasizing grade levels, (2) review cross-coding systems for employment demand data, (3) develop a preliminary system for periodic…

  15. Employer Recruitment Is Not the Problem: A Study of School-to-Work Transition Programs. IEE Brief Number 21.

    ERIC Educational Resources Information Center

    Hughes, Katherine L.

    To study employer motivations for participating in school-to-work (STW) programs, researchers sought programs with a strong work-based learning component, specifically those where employers took students as interns or apprentices for one or two school years. In 1995 and 1996, 1 or 2 site visits were made to each of 12 programs. Researchers toured…

  16. Connecting Work and School: A Statewide Study of Employer Participation in Florida School-to-Work Initiatives.

    ERIC Educational Resources Information Center

    Haley, Mary

    A study assessed the characteristics and practices of employers participating in Florida school-to-work (STW) initiatives, the factors influencing their participation, and the quality and value of their partnerships with schools. Data were gathered through a statewide mail survey of a random sample of employers drawn from more than 15,000 Florida…

  17. Case Study of Employment Trends across 25 Years of Graduates of a Japanese Science and Technology University

    ERIC Educational Resources Information Center

    Nakayama, Minoru

    2014-01-01

    Graduates in the areas of Science and Technology are believed to have traditionally been employed in a number of specific industries, but the recent restructuring of some industries may have affected this phenomenon. In order to examine the trends concerning employment issues in more detail, a case study was conducted by surveying employment…

  18. Does employment improve the health of lone mothers? The ALSPAC Study Team. Avon Longitudinal Study of Pregnancy and Childhood.

    PubMed

    Baker, D; North, K

    1999-07-01

    In Britain the government is currently proposing legislation that will encourage welfare recipients to gain employment. A central tenet of this 'welfare to work' policy is that employment will not only reduce the poverty of welfare recipients, but also improve their health. This research assessed the extent to which the movement from 'welfare to work' is likely to benefit the mental and physical health of lone mothers with preschool children. The sample was 719 lone mothers and a comparison group of 8779 women with partners drawn from the Avon Longitudinal Study of Pregnancy and Childhood (ALSPAC). Data collected by self completion questionnaire at 33 months postpartum provided information about average weekly take home family income and the mother's employment status. The health outcomes measured were general well being, both minor and major depression (using the Edinburgh Postnatal Depression Scale), self report of respiratory symptoms (cough/cold, wheeze, influenza) from 18-33 months postpartum and self report of symptoms common in the childbearing years (backache, haemorrhoids) also from 18-33 months postpartum. Lone mothers who were not employed were the poorest group in the sample; 94% of this group (402) had a family income of less than pound sterling 200 per week, compared with 72% (188) of lone mothers who were employed, 25% (905) of partnered women who were not employed and 12% (466) of partnered women who were employed. Lone mothers were significantly more likely than women with partners to report poorer well being (chi2 = 11.7, df = 3, P = 0.01), to have a major depressive disorder (chi2 = 92.6, df = 1, P = 0.0001) and to report wheeze (chi2 = 31.1, df = 1, P = 0.0001), but significantly less likely to report cough/cold (chi2 = 9.9, df = 1, P = 0.0001) or haemorrhoids (chi2 = 16.6, df = 1, P = 0.0001). Lone mothers who were unemployed and living on less than pound sterling 100 per week were significantly more likely to be depressed (chi2 = 3.9, df = 1

  19. Peculiarities of Employment of Polymeric Miniplates for Mandibular Osteosynthesis: A Preliminary Study

    PubMed Central

    Vares, Yan

    2013-01-01

    Searching for new materials for bone substitution, fixation, and reconstruction is a challenging task that attracts scientists and researchers of different fields of medicine. During the last few decades, much interest has been paid to polymeric materials, polyethylene in particular. The aim of this study is to present generalizations about our own experience in the employment of polyethylene miniplates for the surgical treatment of mandibular fractures. Ninety patients with 139 uni- and bilateral mandibular fractures in different locations were involved. Treatment modalities included open reduction and internal fixation with self-made polyethylene miniplates of straight, T-shaped, Y-shaped, and X-shaped configurations and titanium screws. In 88 (97.8%) cases of surgical treatment of mandibular fractures using polymer miniplates, good anatomical and functional results were achieved. Regardless of the necessity for improvement of some mechanical properties of polyethylene, the results obtained in our clinical investigation allow us to recommend polyethylene miniplates for routine practice. PMID:24436731

  20. Tracing the biotransformation of polychlorinated biphenyls (PCBs) in common carp (Cryprinus carpio): Enantiomeric fraction and compound-specific stable carbon isotope analyses.

    PubMed

    Tang, Bin; Luo, Xiao-Jun; Zeng, Yan-Hong; Sun, Run-Xia; Chen, Hua-Shan; Li, Zong-Rui; Mai, Bi-Xian

    2016-09-01

    Metabolites of polychlorinated biphenyls (PCBs) in fish are difficult to detect in vivo due to the complexity of biometabolism. In the present study, atropisomeric fraction analysis of chiral PCB congeners and compound-specific isotopic analysis (CSIA) were applied to trace the biotransformation of PCBs in fish by exposure of common carp (Cryprinus carpio) to the commercial PCB mixture Aroclor 1242. Stereoselective elimination of the chiral PCB congeners 91, 95, and 136 was observed, indicating a stereoselective biotransformation process. The δ(13)C values of PCBs 5/8, 18, and 20/33 in fish were increased compared with those in the spiked food, while PCBs 47/48 and 49 showed significant heavy isotope depletion. These results suggested a significant biotransformation of the corresponding individual PCB congeners although the potential PCB metabolites, hydroxylated PCBs (OH-PCBs) and methylsulfone PCBs (MeSO2-PCBs), were not detected in the fish tissue samples throughout this experiment. The results of the present study demonstrated that a combination of chiral analysis and CSIA is a promising new approach for investigating the biotransformation of PCBs in biota. PMID:27341148

  1. Do changes in spousal employment status lead to domestic violence? Insights from a prospective study in Bangalore, India.

    PubMed

    Krishnan, Suneeta; Rocca, Corinne H; Hubbard, Alan E; Subbiah, Kalyani; Edmeades, Jeffrey; Padian, Nancy S

    2010-01-01

    The prevalence of physical domestic violence--violence against women perpetrated by husbands--is staggeringly high across the Indian subcontinent. Although gender-based power dynamics are thought to underlie women's vulnerability, relatively little is known about risk and protective factors. This prospective study in southern India examined the association between key economic aspects of gender-based power, namely spousal employment status, and physical domestic violence. In 2005-2006, 744 married women, aged 16-25, residing in low-income communities in Bangalore, India were enrolled in the study. Data were collected at enrollment, 12 and 24 months. Multivariable logistic regression models were used to examine the prospective association between women's employment status, their perceptions of their husband's employment stability, and domestic violence. Women who were unemployed at one visit and began employment by the next visit had an 80% higher odds of violence, as compared to women who maintained their unemployed status. Similarly, women whose husbands had stable employment at one visit and newly had difficulty with employment had 1.7 times the odds of violence, as compared to women whose husbands maintained their stable employment. To our knowledge, this study is the first from a developing country to confirm that changes in spousal employment status are associated with subsequent changes in violence risk. It points to the complex challenges of violence prevention, including the need for interventions among men and gender-transformative approaches to promote gender-equitable attitudes, practices and norms among men and women. PMID:19828220

  2. “Do Changes in Spousal Employment Status Lead to Domestic Violence? Insights from a Prospective Study in Bangalore, India”

    PubMed Central

    Rocca, Corinne H; Hubbard, Alan E; Subbiah, Kalyani; Edmeades, Jeffrey; Padian, Nancy S

    2009-01-01

    The prevalence of physical domestic violence – violence against women perpetrated by husbands – is staggeringly high across the Indian subcontinent. Although gender-based power dynamics are thought to underlie women's vulnerability, relatively little is known about risk and protective factors. This prospective study in southern India examined the association between key economic aspects of gender-based power, namely spousal employment status, and physical domestic violence. In 2005-2006, 744 married women, aged 16-25, residing in low-income communities in Bangalore, India were enrolled in the study. Data were collected at enrolment, 12 and 24 months. Multivariable logistic regression models were used to examine the prospective association between women's employment status, their perceptions of their husband's employment stability, and domestic violence. Women who were unemployed at one visit and began employment by the next visit had an 80% higher odds of violence, as compared to women who maintained their unemployed status. Similarly, women whose husbands had stable employment at one visit and newly had difficulty with employment had 1.7 times the odds of violence, as compared to women whose husbands maintained their stable employment. To our knowledge, this study is the first from a developing country to confirm that changes in spousal employment status are associated with subsequent changes in violence risk. It points to the complex challenges of violence prevention, including the need for interventions among men and gender transformative approaches to promote gender-equitable attitudes, practices and norms among men and women. PMID:19828220

  3. Barriers to Employer Sponsored Training in Ontario. Results of a Field Study.

    ERIC Educational Resources Information Center

    Harvey, Edward B.

    Results of a field survey of Canadian companies, trade unions, employer associations, educational establishments, and government agencies regarding the extent and possibilities of employer-sponsored training for workers are compiled in this report. Concentrating on the forty-nine companies in the survey sample, with collateral data from the…

  4. A Study on Relationship between Personality Traits and Employment Factors of College Students

    ERIC Educational Resources Information Center

    Kai-Wen, Cheng

    2011-01-01

    The goal of vocational education is to enhance students' professional knowledge, technical skills, and professional ethics to make them readily available for employment and capable of satisfying the needs of economic constructions. Vocational education plays an important role in guiding and assisting students in seeking employment. However, in…

  5. Academic Science/Engineering Employment Increased 3% between 1980 and 1981. Science Resources Studies Highlights.

    ERIC Educational Resources Information Center

    National Science Foundation, Washington, DC. Div. of Science Resources Studies.

    Data presented in this report are derived from the National Science Foundation's (NSF) 1981 Survey of Scientific and Engineering Personnel Employed at Universities and Colleges. Highlights of the survey indicate that: 1) science and engineering (S/E) employment in the higher education sector increased 3-percent between January 1980 and January…

  6. Tuning in to Local Labor Markets: Findings from the Sectoral Employment Impact Study

    ERIC Educational Resources Information Center

    Maguire, Sheila; Freely, Joshua; Clymer, Carol; Conway, Maureen; Schwartz, Deena

    2010-01-01

    Over the past two decades, an innovative approach to workforce development known as sectoral employment has emerged, resulting in the creation of industry-specific training programs that prepare unemployed and underskilled workers for skilled positions and connect them with employers seeking to fill such vacancies. In 2003, with funding from the…

  7. Engaging Employers to Develop Quality in Higher Education: The Case of Communication Studies in Italy

    ERIC Educational Resources Information Center

    Romenti, Stefania; Invernizzi, Emanuele; Biraghi, Silvia

    2012-01-01

    This paper explores how employer engagement can enhance potential employability of graduates, which represents a fundamental institutional achievement to ameliorate quality of higher education. While the role of student and staff engagement in quality improvement has received in-depth research attention, the need for listening to expectations of…

  8. Evaluating the Effectiveness of the Family Employment Awareness Training in Kansas: A Pilot Study

    ERIC Educational Resources Information Center

    Francis, Grace; Gross, Judith M. S.; Turnbull, Rud; Parent-Johnson, Wendy

    2013-01-01

    Working in competitive employment (employment in community settings with nondisabled peers for minimum wage or higher) has many positive benefits for people with disabilities who have individualized support needs (Johannesen, McGrew, Griss, & Born, 2007). Nonetheless, many of these individuals work in segregated settings or are unemployed entirely…

  9. A Descriptive Study: Determining the Difference in the Perceptions of Employers

    ERIC Educational Resources Information Center

    Jewette, Karen P.

    2013-01-01

    The U.S. workforce is not prepared for the demands of today's workplace (Conference Board, 2006), Previously, workplace employers emphasized environments where the main thrust was expertise in technical skills of employees. However, a shift occurred that caused employers to realize the importance of soft skills in order to maximize business…

  10. Skills and Security in Evolving Employment Systems: Observations from Case Studies.

    ERIC Educational Resources Information Center

    Brown, Clair; And Others

    An emerging U.S. employment system is the Security, Employee Involvement, and Training (SET) system. The system is characterized by the following: (1) a high degree of employment security based upon flexible job assignment; (2) employee involvement in problem solving and continuous improvement; and (3) continuous training of all employees. Case…

  11. A Study of Barriers to Employment for WIN Mandatory Welfare Recipients.

    ERIC Educational Resources Information Center

    Boeckmann, Margaret

    A descriptive analysis was made of survey data collected on a sample of Work Incentive (WIN) Demonstration Program clients (i.e., mandatory welfare recipients who are required by law to register for employment and training as a condition of benefit receipt) participating in a special employment and training program called OPTIONS in Baltimore…

  12. BIOACCUMULATION, BIOTRANSFORMATION, AND METABOLITE FORMATION OF FIPRONIL AND CHIRAL LEGACY PESTICIDES IN RAINBOW TROUT

    EPA Science Inventory

    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 ...

  13. Employment and arthritis: making it work” a randomized controlled trial evaluating an online program to help people with inflammatory arthritis maintain employment (study protocol)

    PubMed Central

    2014-01-01

    Background Arthritis and musculoskeletal conditions are the leading cause of long-term work disability (WD), an outcome with a major impact on quality of life and a high cost to society. The importance of decreased at-work productivity has also recently been recognized. Despite the importance of these problems, few interventions have been developed to reduce the impact of arthritis on employment. We have developed a novel intervention called “Making It Work”, a program to help people with inflammatory arthritis (IA) deal with employment issues, prevent WD and improve at-work productivity. After favorable results in a proof-of-concept study, we converted the program to a web-based format for broader dissemination and improved accessibility. The objectives of this study are: 1) to evaluate in a randomized controlled trial (RCT) the effectiveness of the program at preventing work cessation and improving at-work productivity; 2) to perform a cost-utility analysis of the intervention. Methods/Design 526 participants with IA will be recruited from British Columbia, Alberta, and Ontario in Canada. The intervention consists of a) 5 online group sessions; b) 5 web-based e-learning modules; c) consultations with an occupational therapist for an ergonomic work assessment and a vocational rehabilitation counselor. Questionnaires will be administered online at baseline and every 6 months to collect information about demographics, disease measures, costs, work-related risk factors for WD, quality of life, and work outcomes. Primary outcomes include at-work productivity and time to work cessation of > 6 months for any reason. Secondary outcomes include temporary work cessation, number of days missed from work per year, reduction in hours worked per week, quality adjusted life year for the cost utility analysis, and changes from baseline in employment risk factors. Analysis of Variance will evaluate the intervention’s effect on at-work productivity, and multivariable

  14. Biotransformation of selamectin with Streptomyces lydicus SX-1298 using a novel static agar fermentation system with Reemay mesh.

    PubMed

    Pacey, M S; Barnes, M M; Monday, R A; Ritzau, M; Wellington, E M

    2001-05-01

    A novel approach to biotransformation is described using a solid medium matrix and Reemay mesh that gives efficient biotransformation of compounds with minimal matrices in the ensuing gum solids. Using this approach with a newly isolated biotransforming organism, Streptomyces lydicus SX1298, a series of hydroxylations and an O-demethylation is described for selamectin the first endectocide for cats and dogs.

  15. Epilepsy and employment--employers' attitudes.

    PubMed

    Cooper, M

    1995-09-01

    The aim of this study was to examine the possible causes of employment difficulties amongst people with epilepsy by interviewing employers. It was hoped that the outcome of the study would complement the research already carried out in this field by concentrating on the attitudes and policies of employers. Due to the time limit it was decided that a small number (five) of local employers should be approached requesting an interview. The employers were randomly selected but were all large companies within varying industries. All employers approached agreed to participate in the study and interviews were arranged with welfare recruitment staff. The interviews were limited to 45 minutes and concentrated on three main issues for discussion: disclosure, unemployment and improved relationship between employers and people with epilepsy. The outcome of the interviews was that the employers appeared to be rather unaware of the employment problems faced by people with epilepsy. As epilepsy is generally not a registered disability employers are unable to monitor their company's recruitment and promotion methods. It seems that line managers are left to decide on the employment of people with epilepsy often without even general awareness training on equal opportunities. Consequently their need to meet targets and their personal attitude to epilepsy determine the employment chances for people with epilepsy. Only with legislations protecting the interests of people with epilepsy can the unemployment figures be brought in line with the general population.

  16. Influence of exposure time on the biotransformation rate of benzo(a)anthracene in fish

    SciTech Connect

    Maagd, P.G.J. de; Poorte, J. de; Sijm, D.T.H.M.; Opperhuizen, A.

    1995-12-31

    Biotransformation of PAH can yield in the formation of carcinogenic metabolites, therefore, determining the rate at which metabolites are formed is of importance to risk assessment. Biotransformation rates can be affected by inducing agents, hormonal status, temperature etc. To determine if biotransformation rates of PAH are influenced by auto-induction, juvenile fathead minnows were exposed to benzo(a)anthracene in water for various exposure times. After exposure for 5, 10, 24, 72, 168 or 336 hours no significant differences between biotransformation rates were found. The variation within each biotransformation rate was less than 20%. From these findings it is concluded that auto-induction by benzo(a)anthracene does not occur in fathead minnow.

  17. Conceptual studies for pressurised water reactor cores employing plutonium erbium zirconium oxide inert matrix fuel assemblies

    NASA Astrophysics Data System (ADS)

    Stanculescu, A.; Kasemeyer, U.; Paratte, J.-M.; Chawla, R.

    1999-08-01

    The most efficient way to enhance plutonium consumption in light water reactors is to eliminate the production of plutonium all together. This requirement leads to fuel concepts in which the uranium is replaced by an inert matrix. At PSI, studies have focused on employing ZrO 2 as inert matrix. Adding a burnable poison to such a fuel proves to be necessary. As a result of scoping studies, Er 2O 3 was identified as the most suitable burnable poison material. The results of whole-core three-dimensional neutronics analyses indicated, for a present-day 1000 MW e pressurised water reactor (PWR), the feasibility of an asymptotic equilibrium four-batch cycle fuelled solely with the proposed PuO 2-Er 2O 3-ZrO 2 inert matrix fuel (IMF). The present paper presents the results of more recent investigations related to `real-life' situations, which call for transition configurations in which mixed IMF and UO 2 assembly loadings must be considered. To determine the influence of the introduction of IMF assemblies on the characteristics of a UO 2-fuelled core, three-dimensional full-core calculations have been performed for a present-day 1000 MW e PWR containing up to 12 optimised IMF assemblies.

  18. The approaches to learning of support workers employed in the care home sector: an evaluation study.

    PubMed

    Cowan, David T; Roberts, Julia D; Fitzpatrick, Joanne M; While, Alison E; Baldwin, Julie

    2004-02-01

    This study examined the approaches to learning of a cohort (n=76) of National Vocational Qualification (NVQ) Care Award candidates using the Approaches and Study Skills Inventory for Students. The NVQ candidates were support workers (SWs) (sometimes called care assistants) employed in United Kingdom (UK) care homes for older people. The aim was to identify SWs' approaches to learning and to determine whether or not a preparatory six-week College-based course had any impact on these approaches. The findings were encouraging. The course had a positive impact with a statistically significant increase in orientation towards a deep learning approach, which is associated with desirable learning outcomes as well as self-directed and lifelong learning skills. The UK government recognises that lifelong learning enables people to continually develop their talents, thereby enhancing local communities and contributing to a civilised, cohesive society. In a health care environment, adopting a deep approach is likely to be beneficial. Those who use evidence to inform practice, who are able to relate elements of what they are taught to their working experiences and who are able to adapt to meet new challenges, are more likely to enhance their practice and become more effective carers. PMID:14769453

  19. The approaches to learning of support workers employed in the care home sector: an evaluation study.

    PubMed

    Cowan, David T; Roberts, Julia D; Fitzpatrick, Joanne M; While, Alison E; Baldwin, Julie

    2004-02-01

    This study examined the approaches to learning of a cohort (n=76) of National Vocational Qualification (NVQ) Care Award candidates using the Approaches and Study Skills Inventory for Students. The NVQ candidates were support workers (SWs) (sometimes called care assistants) employed in United Kingdom (UK) care homes for older people. The aim was to identify SWs' approaches to learning and to determine whether or not a preparatory six-week College-based course had any impact on these approaches. The findings were encouraging. The course had a positive impact with a statistically significant increase in orientation towards a deep learning approach, which is associated with desirable learning outcomes as well as self-directed and lifelong learning skills. The UK government recognises that lifelong learning enables people to continually develop their talents, thereby enhancing local communities and contributing to a civilised, cohesive society. In a health care environment, adopting a deep approach is likely to be beneficial. Those who use evidence to inform practice, who are able to relate elements of what they are taught to their working experiences and who are able to adapt to meet new challenges, are more likely to enhance their practice and become more effective carers.

  20. [Progress in biotransformation of bio-based lactic acid ].

    PubMed

    Gao, Chao; Ma, Cuiqing; Xu, Ping

    2013-10-01

    Fermentative production of lactic acid, an important bio-based chemicals, has made considerable progress. In addition to the food industry and production of polylactic acid, lactic acid also can be used as an important platform chemical for the production of acrylic acid, pyruvic acid, 1,2-propanediol, and lactic acid esters. This article summarizes the recent progress in biocatalytic production of lactic acid derivatives by dehydration, dehydrogenation, reduction, and esterification. Trends in the biotransformation of lactic acid are also discussed. PMID:24432656

  1. Microbial-Catalyzed Biotransformation of Multifunctional Triterpenoids Derived from Phytonutrients

    PubMed Central

    Shah, Syed Adnan Ali; Tan, Huey Ling; Sultan, Sadia; Mohd Faridz, Muhammad Afifi Bin; Mohd Shah, Mohamad Azlan Bin; Nurfazilah, Sharifah; Hussain, Munawar

    2014-01-01

    Microbial-catalyzed biotransformations have considerable potential for the generation of an enormous variety of structurally diversified organic compounds, especially natural products with complex structures like triterpenoids. They offer efficient and economical ways to produce semi-synthetic analogues and novel lead molecules. Microorganisms such as bacteria and fungi could catalyze chemo-, regio- and stereospecific hydroxylations of diverse triterpenoid substrates that are extremely difficult to produce by chemical routes. During recent years, considerable research has been performed on the microbial transformation of bioactive triterpenoids, in order to obtain biologically active molecules with diverse structures features. This article reviews the microbial modifications of tetranortriterpenoids, tetracyclic triterpenoids and pentacyclic triterpenoids. PMID:25003642

  2. Employer Perceptions of Associate Degrees in Local Labor Markets: A Case Study of the Employment of Information Technology Technicians in Detroit and Seattle. CCRC Working Paper No. 39

    ERIC Educational Resources Information Center

    Van Noy, Michelle; Jacobs, James

    2012-01-01

    While promoting postsecondary credential completion is a national priority intended to help graduates secure good jobs, the value of credentials in the labor market from the perspective of employers is not well understood. Specifically, more attention is needed to understand how credentials align with employer needs. Through in-depth interviews…

  3. Biotransformation of furanic and phenolic compounds with hydrogen gas production in a microbial electrolysis cell

    DOE PAGES

    Zeng, Xiaofei; Borole, Abhijeet P.; Pavlostathis, Spyros G.

    2015-10-27

    In this study, furanic and phenolic compounds are problematic byproducts resulting from the decomposition of lignocellulosic biomass during biofuel production. This study assessed 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 sole carbon and energy source in the bioanode. The rate and extent of biotransformation of the five compounds, efficiency of H2 production, as well as the anode microbial community structure were investigated. The five compounds were completelymore » transformed within 7-day batch runs and their biotransformation rate increased with increasing initial concentration. At an initial concentration of 1,200 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 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 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 1,200 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 H2 production route demonstrated in this study has proven to be an alternative to the currently used process of reforming natural gas to supply H2 needed to upgrade bio-oils to stable hydrocarbon fuels.« less

  4. Biotransformation of furanic and phenolic compounds with hydrogen gas production in a microbial electrolysis cell

    SciTech Connect

    Zeng, Xiaofei; Borole, Abhijeet P.; Pavlostathis, Spyros G.

    2015-10-27

    In this study, furanic and phenolic compounds are problematic byproducts resulting from the decomposition of lignocellulosic biomass during biofuel production. This study assessed 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 sole carbon and energy source in the bioanode. The rate and extent of biotransformation of the five compounds, efficiency of H2 production, as well as the anode microbial community structure 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 1,200 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 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 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 1,200 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 H2 production route demonstrated in this study has proven to be an alternative to the currently used process of reforming natural gas to supply H2 needed to

  5. College student employment and drinking: a daily study of work stressors, alcohol expectancies, and alcohol consumption.

    PubMed

    Butler, Adam B; Dodge, Kama D; Faurote, Eric J

    2010-07-01

    We examined the within-person relationships between daily work stressors and alcohol consumption over 14 consecutive days in a sample of 106 employed college students. Using a tension reduction theoretical framework, we predicted that exposure to work stressors would increase alcohol consumption by employed college students, particularly for men and those with stronger daily expectancies about the tension reducing properties of alcohol. After controlling for day of the week, we found that hours worked were positively related to number of drinks consumed. Workload was unrelated to alcohol consumption, and work-school conflict was negatively related to consumption, particularly when students expressed strong beliefs in the tension reducing properties of alcohol. There was no evidence that the effects of work stressors were moderated by sex. The results illustrate that employment during the academic year plays a significant role in college student drinking and suggest that the employment context may be an appropriate intervention site to address the problem of student drinking.

  6. Bioreactor study employing bacteria with enhanced activity toward cyanobacterial toxins microcystins.

    PubMed

    Dziga, Dariusz; Lisznianska, Magdalena; Wladyka, Benedykt

    2014-08-13

    An important aim of white (grey) biotechnology is bioremediation, where microbes are employed to remove unwanted chemicals. Microcystins (MCs) and other cyanobacterial toxins are not industrial or agricultural pollutants; however, their occurrence as a consequence of human activity and water reservoir eutrophication is regarded as anthropogenic. Microbial degradation of microcystins is suggested as an alternative to chemical and physical methods of their elimination. This paper describes a possible technique of the practical application of the biodegradation process. The idea relies on the utilization of bacteria with a significantly enhanced MC-degradation ability (in comparison with wild strains). The cells of an Escherichia coli laboratory strain expressing microcystinase (MlrA) responsible for the detoxification of MCs were immobilized in alginate beads. The degradation potency of the tested bioreactors was monitored by HPLC detection of linear microcystin LR (MC-LR) as the MlrA degradation product. An open system based on a column filled with alginate-entrapped cells was shown to operate more efficiently than a closed system (alginate beads shaken in a glass container). The maximal degradation rate calculated per one liter of carrier was 219.9 µg h-1 of degraded MC-LR. A comparison of the efficiency of the described system with other biological and chemo-physical proposals suggests that this new idea presents several advantages and is worth investigating in future studies.

  7. Bioreactor Study Employing Bacteria with Enhanced Activity toward Cyanobacterial Toxins Microcystins

    PubMed Central

    Dziga, Dariusz; Lisznianska, Magdalena; Wladyka, Benedykt

    2014-01-01

    An important aim of white (grey) biotechnology is bioremediation, where microbes are employed to remove unwanted chemicals. Microcystins (MCs) and other cyanobacterial toxins are not industrial or agricultural pollutants; however, their occurrence as a consequence of human activity and water reservoir eutrophication is regarded as anthropogenic. Microbial degradation of microcystins is suggested as an alternative to chemical and physical methods of their elimination. This paper describes a possible technique of the practical application of the biodegradation process. The idea relies on the utilization of bacteria with a significantly enhanced MC-degradation ability (in comparison with wild strains). The cells of an Escherichia coli laboratory strain expressing microcystinase (MlrA) responsible for the detoxification of MCs were immobilized in alginate beads. The degradation potency of the tested bioreactors was monitored by HPLC detection of linear microcystin LR (MC-LR) as the MlrA degradation product. An open system based on a column filled with alginate-entrapped cells was shown to operate more efficiently than a closed system (alginate beads shaken in a glass container). The maximal degradation rate calculated per one liter of carrier was 219.9 µg h−1 of degraded MC-LR. A comparison of the efficiency of the described system with other biological and chemo-physical proposals suggests that this new idea presents several advantages and is worth investigating in future studies. PMID:25123557

  8. Study of the characteristics of participants and nonparticipants in employer sponsored vanpools. [Three Houston organizations

    SciTech Connect

    Boggs, P.T.

    1984-01-01

    The purpose of this study was to develop a set of variables that differentiates between participants and nonparticipants in employer sponsored vanpools and, using these variables, to determine if significant differences exist. Twenty-two variables and dimensions were postulated to impact a commuter's decision to vanpool. The items comprising the dimensions were originally formulated on the basis of past research, interview of employees at an organization having a vanpool program, and conversations with vanpool coordinators around the country. To validate the dimensions, a pretest of the survey was administered and the results factor-analyzed. The final dimension definitions were based on factor analysis results for pretest and final data and a priori definitions. A stepwise discriminant analysis was performed using the 22 variables and dimensions as predictor variables to obtain a subset of predictor variables for the final analysis. The dependent variable was a dichotomous variable indicating if the respondent was a participant or nonparticipant in the vanpool program. The subset of variables in the function at the last iteration were: convenience, cost of mode, noise pollution, vanpool reliability, child daycare, miles, overtime, and sex. These nine variables were then used as predictor variables in the analysis of the final data collected from three organizations in Houston, Texas

  9. From the outside Looking in: A Study of Australian Employers' Perceptions of Graduates from Outdoor Education Degree Programs

    ERIC Educational Resources Information Center

    Munge, Brendan

    2009-01-01

    This paper reports on a study conducted in 2006-07 exploring the perspectives that some Australian employers have of graduates from an outdoor education degree program. Similar studies have been conducted in the US and the UK; however no such study has been conducted in Australia. This study clarifies some of the tensions that exist in the…

  10. Employment and sociodemographic characteristics: a study of increasing precarity in the health districts of Belo Horizonte, Brazil

    PubMed Central

    Coelho, Maria Cristina Ramos de Vasconcellos; Assunção, Ada Ávila; Belisário, Soraya Almeida

    2009-01-01

    Background The fundamental importance of human resources for the development of health care systems is recognized the world over. Health districts, which constitute the middle level of the municipal health care system in the city of Belo Horizonte, Brazil, deal with demands from all parts of the system. This research seeks to provide the essential features required in order to understand the phenomenon of increase in precarity of employment in these health districts. Methods The legal and human resource management documents used by the Municipal Health Secretariat of the City of Belo Horizonte were adopted as the corpus for this research. In order to analyse the changes in employment (2002–2006), the data were collected from ArteRH, a computerized database dealing specifically with data related to human resources, which began operating in 2001. The workers were classified into permanent and non-permanent groups, and their contractual rights were described. Employment dynamics and changes were examined, concentrating on the incorporation of workers and on their social and employment rights during the period under study. The comparative data for the two groups obtained were presented in frequency distribution tables according to type of employment, sex, age group, level of education and wages from 2002 to 2006. Results There was a clear difference between the permanent worker and non-permanent worker groups as regards existing guaranteed employment rights and social security. The increase in the number of non-permanent workers in the workforce, the growing proportion of older workers among the permanently employed and the real wage reductions during the period from 2002 to 2006 are indicative of the process of growing precarity of employment in the group studied. Conclusion It is a plausible supposition that the demand for health reforms, along with the legal limits imposed on financial expenditure, gave rise to the new types of contract and the present employment

  11. Biotransformation of the Antimelanoma Agent Betulinic Acid by Bacillus megaterium ATCC 13368

    PubMed Central

    Chatterjee, Parnali; Kouzi, Samir A.; Pezzuto, John M.; Hamann, Mark T.

    2000-01-01

    Microbial transformation of the antimelanoma agent betulinic acid was studied. The main objective of this study was to utilize microorganisms as in vitro models to predict and prepare potential mammalian metabolites of this compound. Preparative-scale biotransformation with resting-cell suspensions of Bacillus megaterium ATCC 13368 resulted in the production of four metabolites, which were identified as 3-oxo-lup-20(29)-en-28-oic acid, 3-oxo-11α-hydroxy-lup-20(29)-en-28-oic acid, 1β-hydroxy-3-oxo-lup-20(29)-en-28-oic acid, and 3β,7β,15α-trihydroxy-lup-20(29)-en-28-oic acid based on nuclear magnetic resonance and high-resolution mass spectral analyses. In addition, the antimelanoma activities of these metabolites were evaluated with two human melanoma cell lines, Mel-1 (lymph node) and Mel-2 (pleural fluid). PMID:10966400

  12. Clinical and cognitive correlates of employment among patients with schizophrenia: a cross-sectional study in Malaysia

    PubMed Central

    2011-01-01

    Background Gainful employment is one major area of functioning which is becoming an important goal in psychiatric rehabilitation of patients with schizophrenia. Studies in western countries are pointing to evidence that certain sociodemographic and clinical factors may contribute to employment outcomes in this group of people. However, the area is still largely unexplored in Malaysia. The aim of this study was to examine the sociodemographic, clinical and cognitive correlates of employment status among patients with Schizophrenia. Methods This was a cross-sectional study. All participants who fulfilled the requirements of the study according to the inclusion and exclusion criteria were enrolled. Study instruments included a demographic data questionnaire, Positive and Negative Symptom Scale (PANSS), Trail Making Tests, Rey's Auditory Verbal Learning Test (RAVLT) and Digit Span. Bivariate analyses were done using chi-square for categorical data and t-test for continuous data and multiple logistic regression analysis was done to identify predictors of employment status. Results A total of 95 participants who fulfilled the inclusion criteria were enrolled into the study. Among the sociodemographic, clinical and cognitive variables studied marital status, educational level, mean scores of negative symptoms, Digit Span and RAVLT and Trail Making Tests were found to show significant association with employment status on bivariate analyses. However, when entered into a logistic regression model, only cognitive variables ie. Trail A and B, Digit Span and RAVLT were significant predictors of employment status. Conclusions The results from this study support the role of cognitive function, particularly, attention, working memory and executive functioning on attaining and maintaining employment in persons with schizophrenia as measured by the RAVLT, Digit Span and Trail Making Tests. These findings may act as preliminary evidence suggesting the importance of integrating

  13. Employers' readiness for the mother-friendly workplace: an elicitation study.

    PubMed

    Bai, Yeon K; Wunderlich, Shahla M; Weinstock, Marni

    2012-10-01

    Currently over half of mothers of infants under 1-year-old are in the workforce in the United States. These women face challenges to continue breastfeeding when they return to work 3 to 6 months post-partum. This study explored the perspectives of employers on mother-friendly environments to assess their readiness to provide breastfeeding accommodation using the elicitation under the theory of planned behaviour. Researchers conducted phone/in-person interviews with a convenient sample of 20 human resource managers from companies that had 500 or more employees in the New York metropolitan area in 2009. Content analyses identified the common concepts that represent underlying beliefs of the constructs of the theory. The demography of the participants is 40% male and 80% White, with mean ages of 34.3±8.5 years. 'Happy employees' and 'high retention rate and improved loyalty' were the most frequently mentioned (95%) benefits to the company (behavioural beliefs). Supporters of a mother-friendly environment (normative beliefs) in the workplace included 'mothers and expectant mothers (70%)', and 'managers supervising women and new mothers (55%)'. Most frequently mentioned company drawbacks (control beliefs) were 'not cost effective (65%)' and 'time consuming (65%)', followed by 'perception of special favours for some (50%)'. Workplace breastfeeding promotion efforts can be successful by reinforcing positive beliefs and addressing the challenges associated with implementation of breastfeeding accommodation through education and other incentives such as recognition of model companies and tax breaks. The identified beliefs provide a basis for the development of a quantitative instrument to study workplace breastfeeding support further. PMID:21978139

  14. A Follow-Up Study of Graduates' and Employers' Opinions of a Cooperating Training Program. Research Study No. 1.

    ERIC Educational Resources Information Center

    Tuttle, David Chester

    Interviews collected information from 135 graduates of the trades and industrial cooperative education training program, and 30 employers in Des Moines, Iowa, to appraise the effectiveness of training in relation to post high school employment. Graduates and employers commented on the value of core area training, school counseling, and different…

  15. enviPath – The environmental contaminant biotransformation pathway resource

    PubMed Central

    Wicker, Jörg; Lorsbach, Tim; Gütlein, Martin; Schmid, Emanuel; Latino, Diogo; Kramer, Stefan; Fenner, Kathrin

    2016-01-01

    The University of Minnesota Biocatalysis/Biodegradation Database and Pathway Prediction System (UM-BBD/PPS) has been a unique resource covering microbial biotransformation pathways of primarily xenobiotic chemicals for over 15 years. This paper introduces the successor system, enviPath (The Environmental Contaminant Biotransformation Pathway Resource), which is a complete redesign and reimplementation of UM-BBD/PPS. enviPath uses the database from the UM-BBD/PPS as a basis, extends the use of this database, and allows users to include their own data to support multiple use cases. Relative reasoning is supported for the refinement of predictions and to allow its extensions in terms of previously published, but not implemented machine learning models. User access is simplified by providing a REST API that simplifies the inclusion of enviPath into existing workflows. An RDF database is used to enable simple integration with other databases. enviPath is publicly available at https://envipath.org with free and open access to its core data. PMID:26582924

  16. Accumulation and biotransformation of vanadium in Opuntia microdasys.

    PubMed

    Yang, Jin-Yan; Tang, Ya

    2015-04-01

    The accumulation and biotransformation of vanadium (V) in Opuntia microdasys were investigated under hydroponic conditions to determine the toxicity of pentavalent V [i.e., V(V)] to the plant and the mechanism of tolerance by the plant to V. Results showed that the concentration of V(V) in nutrient solution was negatively correlated to plant biomass. Moreover, the water content of cladodes decreased under V(V) stress. In V(V)-treated plants, most of the adsorbed V remained in the roots and in the cell wall compartment. In the cladodes, the ratios of V(V) to Vtotal were lower in V(V)-treated plants than those in the control plants. These results indicate that a high concentration of V(V) is toxic to O. microdasys but that the plants may limit this toxicity through the compartmentalization of V in the cell wall and the biotransformation of V from V(V) to tetravalent V [i.e., V(IV)].

  17. Biotransformation of potentially persistent alkylphenols in natural seawater.

    PubMed

    Lofthus, Synnøve; Almås, Inger K; Evans, Peter; Pelz, Oliver; Brakstad, Odd Gunnar

    2016-08-01

    Produced water (PW) discharged to the marine environment may contain both natural substances and industrial chemicals that are potentially persistent, bioaccumulating and toxic (PBT). Identification of substances as PBT is dependent upon accurate assessment of biodegradation rates, but these measurements can be impeded where substances exhibit inherently low solubility in water. Examples of substances of this kind include some alkylated phenols (APs). Biotransformation of three APs, suspected to be PBT compounds in PW, was investigated by adopting a new methodology in which they were immobilized to hydrophobic adsorbents submerged in natural seawater. These compounds were not ready biodegradable by conventional screening biochemical oxygen demand (BOD) methods at high concentrations (2 mg/L). However, potential biodegradability for two of the three APs were demonstrated by the immobilization method at low concentrations (appr. 100 μg/L), with biotransformation half-lives <50 days. Thus, standard screening tests should be supplemented by biodegradation methods suited for testing of poorly soluble substances before the persistence of potential PBT substances are defined. PMID:27176941

  18. Accumulation and biotransformation of vanadium in Opuntia microdasys.

    PubMed

    Yang, Jin-Yan; Tang, Ya

    2015-04-01

    The accumulation and biotransformation of vanadium (V) in Opuntia microdasys were investigated under hydroponic conditions to determine the toxicity of pentavalent V [i.e., V(V)] to the plant and the mechanism of tolerance by the plant to V. Results showed that the concentration of V(V) in nutrient solution was negatively correlated to plant biomass. Moreover, the water content of cladodes decreased under V(V) stress. In V(V)-treated plants, most of the adsorbed V remained in the roots and in the cell wall compartment. In the cladodes, the ratios of V(V) to Vtotal were lower in V(V)-treated plants than those in the control plants. These results indicate that a high concentration of V(V) is toxic to O. microdasys but that the plants may limit this toxicity through the compartmentalization of V in the cell wall and the biotransformation of V from V(V) to tetravalent V [i.e., V(IV)]. PMID:25708296

  19. enviPath--The environmental contaminant biotransformation pathway resource.

    PubMed

    Wicker, Jörg; Lorsbach, Tim; Gütlein, Martin; Schmid, Emanuel; Latino, Diogo; Kramer, Stefan; Fenner, Kathrin

    2016-01-01

    The University of Minnesota Biocatalysis/Biodegradation Database and Pathway Prediction System (UM-BBD/PPS) has been a unique resource covering microbial biotransformation pathways of primarily xenobiotic chemicals for over 15 years. This paper introduces the successor system, enviPath (The Environmental Contaminant Biotransformation Pathway Resource), which is a complete redesign and reimplementation of UM-BBD/PPS. enviPath uses the database from the UM-BBD/PPS as a basis, extends the use of this database, and allows users to include their own data to support multiple use cases. Relative reasoning is supported for the refinement of predictions and to allow its extensions in terms of previously published, but not implemented machine learning models. User access is simplified by providing a REST API that simplifies the inclusion of enviPath into existing workflows. An RDF database is used to enable simple integration with other databases. enviPath is publicly available at https://envipath.org with free and open access to its core data. PMID:26582924

  20. Coculture of genetically transformed roots and shoots for synthesis, translocation, and biotransformation of secondary metabolites.

    PubMed

    Subroto, M A; Kwok, K H; Hamill, J D; Doran, P M

    1996-03-01

    Genetically transformed shooty teratomas of Atropa belladonna and a Duboisia leichhardtii x D. myoporoides hybrid were studied for biotransformation of tropane alkaloids in shake flasks and bioreactors. Although de novo synthesis of hyoscyamine and scopolamine was limited, shoots of both species were able to translocate and accumulate significant quantities of exogenous alkaloid. The maximum yield of scopolamine from hyoscyamine fed to the Duboisia hybrid shoots was 35% w/w; the yield of the scopolamine precursor, 6beta-hydroxyhyoscyamine, was 37% w/w. Biotransformation activity was poor in A. belladonna shooty teratomas provided with exogenous hyoscyamine; however, scopolamine levels comparable with those in leaves of the whole plant accumulated in shoots fed with hairy root extract. Coculture of A. belladonna shooty teratomas and hairy roots in the same hormone-free medium was investigated as a means of providing a continuous source of hyoscyamine for conversion to scopolamine. Of the biotransformation systems tested with A. belladonna, coculture produced the highest levels of scopolamine and the highest scopolamine: hyoscyamine ratios. Cocultured shoots accumulated up to 0.84 mg g(-1) dry weight scopolamine, or 3-11 times the average concentrations found in leaves of the whole plant. The scopolamine: hyoscyamine ratio in coculture ranged from 0.07 to 1.9, a significant improvement over levels of 0-0.03 normally found in A. belladonna hairy roots. Addition of Pluronic F-68 or copper sulfate to the medium and variation in initial medium pH did not improve hyoscyamine release from hairy roots. Scopolamine levels were increased using 1 microM copper sulfate or initial medium pH between 6.0 and 8.0; however, results from elicitation of hairy roots could not match the beneficial effect on scopolamine synthesis of root-shoot coculture. Addition of 0.001-1.0% (w/v) Pluronic F-68 to the roots reduced hyoscyamine release but postponed necrosis in the root tissue for up to

  1. Biotransformation of 2,3,3,3-tetrafluoropropene (HFO-1234yf) in rabbits

    SciTech Connect

    Schuster, Paul; Bertermann, Ruediger; Rusch, Georg M.; Dekant, Wolfgang

    2010-05-01

    2,3,3,3-Tetrafluoropropene (HFO-1234yf) is a non-ozone-depleting fluorocarbon replacement with a low global warming potential and is developed as refrigerant. Due to lethality observed after high concentration inhalation exposures of HFO-1234yf in a developmental toxicity study with rabbits, the biotransformation of HFO-1234yf was investigated in this species. Female New Zealand White rabbits were exposed to air containing 2000; 10,000; or 50,000 ppm (n = 3/concentration) HFO234yf. All inhalation exposures were conducted for 6 h in a dynamic exposure chamber. Animals were individually housed in metabolic cages after the end of the exposures and urines were collected at 12 h intervals for 60 h. For metabolite identification, urine samples were analyzed by {sup 1}H-coupled and {sup 1}H-decoupled {sup 19}F-NMR and by LC/MS-MS or GC/MS. Metabolites were identified by {sup 19}F-NMR chemical shifts, signal multiplicity, {sup 1}H-{sup 19}F coupling constants and by comparison with synthetic reference compounds. In urine samples of rabbits exposed to 2000; 10,000; or 50,000 ppm HFO-1234yf, the predominant metabolite was N-acetyl-S-(3,3,3-trifluoro-2-hydroxypropanyl)-L-cysteine and accounted for app. 48% of total {sup 19}F-NMR signal intensities. S-(3,3,3-Trifluoro-2-hydroxypropanyl)mercaptolactic acid, 3,3,3-trifluoro-1,2-dihydroxypropane, 3,3,3-trifluoro-2-propanol and inorganic fluoride were also present as urinary metabolites. In incubations of rabbit liver S9 fractions containing glutathione, NADPH and HFO-1234yf, 3,3,3-trifluoro-1,2-dihydroxypropane, S-(3,3,3-trifluoro-2-hydroxypropanyl)glutathione, 3,3,3-trifluoro-2-propanol and inorganic fluoride were identified as metabolites of HFO-1234yf by {sup 19}F-NMR. The quantity of recovered metabolites in urine suggest a low extent (< 0.1% of dose received) of biotransformation of HFO-1234yf in rabbits, and 95% of all metabolites were excreted within 12 h after the end of the exposures (t{sub 1/2} app. 9.5 h). The obtained

  2. Microbial Biotransformation of Gentiopicroside by the Endophytic Fungus Penicillium crustosum 2T01Y01

    PubMed Central

    Zeng, Wen-Liang; Li, Wan-Kui; Han, Han; Tao, Yan-Yan; Yang, Li; Chen, Kai-Xian

    2014-01-01

    Endophytic fungi are symbiotic with plants and possess multienzyme systems showing promising metabolite potency with region selectivity and stereoselectivity. The aim of this study was to use these special microorganisms as an in vitro model to mimic the potential mammalian metabolites of a natural iridoid gentiopicroside (GPS, compound 1). The fungi isolated from a medicinal plant, Dendrobium candidum Wall. ex Lindl., were screened for their biotransformation abilities with GPS as the substrate, and one strain with high converting potency was identified as Penicillium crustosum 2T01Y01 on the basis of the sequence of the internal transcribed spacer of the ribosomal DNA region. Upon the optimized incubation of P. crustosum 2T01Y01 with the substrate, seven deglycosylated metabolites were detected by ultraperformance liquid chromatography/quadrupole time of flight mass spectrometry (UPLC/Q-TOF MS). Preparative-scale biotransformation with whole cells of the endophytic fungus resulted in the production of five metabolites, including three novel ones, 5α-(hydroxymethyl)-6β-methyl-3,4,5,6-tetrahydropyrano[3,4-c]pyran-1(8H)-one (compound 2), (Z)-4-(1-hydroxybut-3-en-2-yl)-5,6-dihydropyran-2-one (compound 3), and (E)-4-(1-hydroxybut-3-en-2-yl)-5,6-dihydropyran-2-one (compound 4), along with two known ones, 5α-(hydroxymethyl)-6β-methyl-1H,3H-5,6-dihydropyrano[3,4-c]pyran-1(3H)-one (compound 5) and 5α-(hydroxymethyl)-6α-methyl-5,6-dihydropyrano[3,4-c]pyran-1(3H)-one (compound 6), aided by nuclear magnetic resonance and high-resolution mass spectral analyses. The other two metabolites were tentatively identified by online UPLC/Q-TOF MS as 5-hydroxymethyl-5,6-dihydroisochromen-1-one (compound 7) and 5-hydroxymethyl-3,4,5,6-tetrahydroisochromen-1-one (compound 8), and compound 8 is a new metabolite. To test the metabolic mechanism, the β-glucosidase activity of the fungus P. crustosum 2T01Y01 was assayed with ρ-nitrophenyl-β-d-glucopyranoside as a probe substrate

  3. Biotransformation of ethanol to ethyl glucuronide in a rat model after a single high oral dosage.

    PubMed

    Wright, Trista H; Ferslew, Kenneth E

    2012-03-01

    Ethyl glucuronide (EtG) is a minor ethanol metabolite that confirms the absorption and metabolism of ethanol after oral or dermal exposure. Human data suggest that maximum blood EtG (BEtG) concentrations are reached between 3.5 and 5.5h after ethanol administration. This study was undertaken to determine if the Sprague-Dawley (SD) rat biotransforms ethanol to EtG after a single high oral dose of ethanol. SD rats (male, n=6) were gavaged with a single ethanol dose (4 g/kg), and urine was collected for 3 h in metabolic cages, followed by euthanization and collection of heart blood. Blood and urine were analyzed for ethanol and EtG by gas chromatography and enzyme immunoassay. Blood and urine ethanol concentrations were 195±23 and 218±19 mg/dL, whereas BEtG and urine EtG (UEtG) concentrations were 1,363±98 ng equivalents/mL and 210±0.29 mg equivalents/dL (X ± standard error of the mean [S.E.M.]). Sixty-six male SD rats were gavaged ethanol (4 g/kg) and placed in metabolic cages to determine the extent and duration of ethanol to EtG biotransformation and urinary excretion. Blood and urine were collected up to 24 h after administration for ethanol and EtG analysis. Maximum blood ethanol, urine ethanol, and UEtG were reached within 4 h, whereas maximum BEtG was reached 6 h after administration. Maximum concentrations were blood ethanol, 213±20 mg/dL; urine ethanol, 308±34 mg/dL; BEtG, 2,683±145 ng equivalents/mL; UEtG, 1.2±0.06 mg equivalents/mL (X±S.E.M.). Areas under the concentration-time curve were blood ethanol, 1,578 h*mg/dL; urine ethanol, 3,096 h*mg/dL; BEtG, 18,284 h*ng equivalents/mL; and UEtG, 850 h*mg equivalents/dL. Blood ethanol and BEtG levels were reduced to below limits of detection (LODs) within 12 and 18 h after ethanol administration. Urine ethanols were below LOD at 18 h, but UEtG was still detectable at 24h after administration. Our data prove that the SD rat biotransforms ethanol to EtG and excretes both in the urine and suggest that it

  4. Biotransformation of ethanol to ethyl glucuronide in a rat model after a single high oral dosage.

    PubMed

    Wright, Trista H; Ferslew, Kenneth E

    2012-03-01

    Ethyl glucuronide (EtG) is a minor ethanol metabolite that confirms the absorption and metabolism of ethanol after oral or dermal exposure. Human data suggest that maximum blood EtG (BEtG) concentrations are reached between 3.5 and 5.5h after ethanol administration. This study was undertaken to determine if the Sprague-Dawley (SD) rat biotransforms ethanol to EtG after a single high oral dose of ethanol. SD rats (male, n=6) were gavaged with a single ethanol dose (4 g/kg), and urine was collected for 3 h in metabolic cages, followed by euthanization and collection of heart blood. Blood and urine were analyzed for ethanol and EtG by gas chromatography and enzyme immunoassay. Blood and urine ethanol concentrations were 195±23 and 218±19 mg/dL, whereas BEtG and urine EtG (UEtG) concentrations were 1,363±98 ng equivalents/mL and 210±0.29 mg equivalents/dL (X ± standard error of the mean [S.E.M.]). Sixty-six male SD rats were gavaged ethanol (4 g/kg) and placed in metabolic cages to determine the extent and duration of ethanol to EtG biotransformation and urinary excretion. Blood and urine were collected up to 24 h after administration for ethanol and EtG analysis. Maximum blood ethanol, urine ethanol, and UEtG were reached within 4 h, whereas maximum BEtG was reached 6 h after administration. Maximum concentrations were blood ethanol, 213±20 mg/dL; urine ethanol, 308±34 mg/dL; BEtG, 2,683±145 ng equivalents/mL; UEtG, 1.2±0.06 mg equivalents/mL (X±S.E.M.). Areas under the concentration-time curve were blood ethanol, 1,578 h*mg/dL; urine ethanol, 3,096 h*mg/dL; BEtG, 18,284 h*ng equivalents/mL; and UEtG, 850 h*mg equivalents/dL. Blood ethanol and BEtG levels were reduced to below limits of detection (LODs) within 12 and 18 h after ethanol administration. Urine ethanols were below LOD at 18 h, but UEtG was still detectable at 24h after administration. Our data prove that the SD rat biotransforms ethanol to EtG and excretes both in the urine and suggest that it

  5. Biotransformation of Stypotriol triacetate by Aspergillus niger

    NASA Astrophysics Data System (ADS)

    Areche, Carlos; Vaca, Inmaculada; Labbe, Pamela; Soto-Delgado, Jorge; Astudillo, Luis; Silva, Mario; Rovirosa, Juana; San-Martin, Aurelio

    2011-07-01

    Biological transformation of the meroditerpenoid, stypotriol triacetate ( 1) by the fungi Aspergillus niger, Cunninghamella elegans, Gibberella fujikuroi and Mucor plumbeus was studied. The incubation of 1 with A. niger yielded the new compound 6',14-diacetoxy-stypol-4,5-dione ( 2) whose structure was established by 1H, 13C and 2D NMR and supported by DFT/GIAO.

  6. Disability rights advocacy and employment: a qualitative study of the National Centre for the Employment of Disabled People (NCPEDP) in India.

    PubMed

    Benshoff, Laura; Barrera, Magda; Heymann, Jody

    2014-01-01

    In India, the low rate of employment of people with disabilities is a large problem in the growing economy. Looking at one advocacy group's strategies for influencing the private sector and lobbying the Indian government for more responsive employment policies, this article focuses on NCPEDP's holistic approach to increasing employment of people with disabilities as an example of notable, innovative practice. The article examines NCPEDP's strategies towards the private sector, public policy, and civil society, including its Disability Awards (highlighting inclusive workplaces), the 2001 and 2011 Census campaigns' efforts for people with disabilities to become accurately counted, and its networks of disability organizations that disseminate relevant information and campaign for greater equality across the nation. The benefits and limitations of these strategies are then assessed for lessons regarding the strategies available to small nongovernmental organizations seeking to influence employment, the private sector and public policy in other settings.

  7. Effectiveness of Facebook Based Learning to Enhance Creativity among Islamic Studies Students by Employing Isman Instructional Design Model

    ERIC Educational Resources Information Center

    Alias, Norlidah; Siraj, Saedah; Daud, Mohd Khairul Azman Md; Hussin, Zaharah

    2013-01-01

    The study examines the effectiveness of Facebook based learning to enhance creativity among Islamic Studies students in the secondary educational setting in Malaysia. It describes the design process by employing the Isman Instructional Design Model. A quantitative study was carried out using experimental method and background survey. The…

  8. Breast milk expression among formally employed women in urban and rural Malaysia: A qualitative study

    PubMed Central

    2012-01-01

    Background Many women are unable to practice exclusive breastfeeding because they are separated from their infants while working. Expressing their breast milk helps them to continue breastfeeding. This study explores the perception and experiences related to the feasibility, acceptability and safety of breast milk expression among formally employed women in Kelantan, Malaysia. Methods A qualitative method using in-depth interviews was conducted from December 2008 to December 2009 among Malay women from urban and rural areas. A snowball sampling method was used to recruit the informants, and the interviews, which were facilitated by an interview guide, were audio-recorded and transcribed verbatim. Thematic analysis was conducted, with construction of codes and themes from each interview. Results Analysis of the interviews with 20 informants identified three themes related to breast milk expression. The themes were as follows: (i) lack of feasibility of expressing breast milk, (ii) negative feelings about expressing breast milk, and (iii) doubts about the safety and hygiene of expressed breast milk. The informants who did not practice exclusive breastfeeding believed that expressing their breast milk was not feasible, commonly because they felt there were not enough facilities for them. They also had negative feelings such as embarrassment. The safety and hygiene of the expressed breast milk was also their main concern. Conclusion More practical and focused education, as well as provision of facilities, is needed for women to effectively and safely express and store their breast milk. The issue of inadequate milk production should be emphasized, especially by encouraging them to express their breast milk as a way to improve milk production. PMID:22929649

  9. Arsenic biotransformation and release by bacteria indigenous to arsenic contaminated groundwater.

    PubMed

    Paul, Dhiraj; Kazy, Sufia K; Banerjee, Tirtha Das; Gupta, Ashok K; Pal, Taraknath; Sar, Pinaki

    2015-01-01

    Arsenic (As) biotransformation and release by indigenous bacteria from As rich groundwater was investigated. Metabolic landscape of 173 bacterial isolates indicated broad catabolic repertoire including abundance of As(5+) reductase activity and abilities in utilizing wide ranges of organic and inorganic respiratory substrates. Abundance of As homeostasis genes and utilization of hydrocarbon as carbon/electron donor and As(5+) as electron acceptor were noted within the isolates. Sediment microcosm study (for 300 days) showed a pivotal role of metal reducing facultative anaerobic bacteria in toxic As(3+) release in aqueous phase. Inhabitant bacteria catalyze As transformation and facilitate its release through a cascade of reactions including mineral bioweathering and As(5+) and/or Fe(3+) reduction activities. Compared to anaerobic incubation with As(5+) reducing strains, oxic state and/or incubation with As(3+) oxidizing bacteria resulted in reduced As release, thus indicating a strong role of such condition or biocatalytic mechanism in controlling in situ As contamination.

  10. Isolation and screening of microorganisms for R-(+)-limonene and (-)-beta-pinene biotransformation.

    PubMed

    Rottava, Ieda; Cortina, Priscila F; Grando, Camila E; Colla, André R S; Martello, Eduarda; Cansian, Rogério L; Toniazzo, Geciane; Treichel, Helen; Antunes, Octávio A C; Oestreicher, Enrique G; de Oliveira, Débora

    2010-10-01

    This work is focused on the biotransformation of R-(+)-limonene and (-)-beta-pinene to bioflavor production. To carry out the present study, 405 microorganisms were tested for their ability to bioconvert the substrates. From the isolated microorganisms, 193 were selected in the prescreening using mineral medium for limonene degradation. At the screening step, eight strains were able to convert R-(+)-limonene and 15 to transform (-)-beta-pinene, both in alpha-terpineol. The highest concentration in alpha-terpineol from R-(+)-limonene was about 3,450 mg/L for Penicillium sp. isolated from eucalyptus steam. From (-)-beta-pinene, the highest product concentration of 675.5 mg/L was achieved using an Aspergillus sp. strain isolated from orange tree stem.

  11. On the biotransformation of ent-trachylobane to ent-kaur-11-ene diterpenes.

    PubMed

    Fraga, Braulio M; Gonzalez-Vallejo, Victoria; Guillermo, Ricardo

    2011-09-23

    The microbiological transformation of trachinodiol (1) by the fungus Mucor plumbeus afforded the corresponding 1α, 2α, 3α, and 17-hydroxy derivatives (2-4 and 6), respectively. 7β,16α,18-Trihydroxy-ent-kaur-11-ene (sicanatriol) (5) was also obtained in this feeding. The biotransformation of 1 to give 5 by this fungus may occur by enzymatic abstraction of a hydrogen atom, allylic to the cyclopropane ring, and subsequent cleavage of this ring. This route is similar to that postulated by us in plants of the genus Sideritis, where ent-trachylobane and ent-kaur-11-ene diterpenes coexist. This study confirms that hydroxylation of diterpenes by M. plumbeus occurs preferably at ring A carbons.

  12. Arsenic biotransformation and release by bacteria indigenous to arsenic contaminated groundwater.

    PubMed

    Paul, Dhiraj; Kazy, Sufia K; Banerjee, Tirtha Das; Gupta, Ashok K; Pal, Taraknath; Sar, Pinaki

    2015-01-01

    Arsenic (As) biotransformation and release by indigenous bacteria from As rich groundwater was investigated. Metabolic landscape of 173 bacterial isolates indicated broad catabolic repertoire including abundance of As(5+) reductase activity and abilities in utilizing wide ranges of organic and inorganic respiratory substrates. Abundance of As homeostasis genes and utilization of hydrocarbon as carbon/electron donor and As(5+) as electron acceptor were noted within the isolates. Sediment microcosm study (for 300 days) showed a pivotal role of metal reducing facultative anaerobic bacteria in toxic As(3+) release in aqueous phase. Inhabitant bacteria catalyze As transformation and facilitate its release through a cascade of reactions including mineral bioweathering and As(5+) and/or Fe(3+) reduction activities. Compared to anaerobic incubation with As(5+) reducing strains, oxic state and/or incubation with As(3+) oxidizing bacteria resulted in reduced As release, thus indicating a strong role of such condition or biocatalytic mechanism in controlling in situ As contamination. PMID:25782634

  13. The biotransformation of brewer's spent grain into biogas by anaerobic microbial communities.

    PubMed

    Malakhova, Dina V; Egorova, Maria A; Prokudina, Ljuba I; Netrusov, Alexander I; Tsavkelova, Elena A

    2015-12-01

    The present study reports on the biotransformation of the brewer's spent grain (BSG) in co-digestion with Jerusalem artichoke (JA, Helianthus tuberosus L.) phytomass by thermophilic (+55 °C) and mesophilic (+30 °C) anaerobic methanogenic communities. BSG is a by-product of the beer-brewing process generated in large amounts, in which utilization provokes a negative effect on the environment. In this study, we will show an effective conversion of BSG into biogas by selected microbial communities, obtained from different sources (animal manure and previously isolated microbial consortia). The stimulation of methanogenesis was reached by the co-digestion of JA's phytomass (stem and leaves). The optimized conditions for microbial stable cultivation included the use of nutrient medium, containing yeast extract and trace element solution. The optimal BSG concentration in biogas production was 50 and 100 g L(-1). Under thermophilic conditions, the maximum total methane production reached 64%, and it comprised around 6-8 and 9-11 of L CH4 per 100 g of fermented BSG without and with co-digested JA, respectively, when the fresh inoculum was added. Although, after a year of re-cultivation, the values reduced to around 6-7, and 6-10 L CH4/100 g BSG, correspondingly, the selected microbial communities showed effective biotransformation of BSG. The supplementation of soil with the residual fermented BSG (10%, w/w) resulted in the promotion of lettuce (Lepidium sativum L.) growth. The results obtained demonstrate a potential for complete BSG utilization via biogas production and application as a soil additive.

  14. Evaluation of hepatic biotransformation of polybrominated diphenyl ethers in the polar bear (Ursus maritimus).

    PubMed

    Krieger, Lisa K; Szeitz, András; Bandiera, Stelvio M

    2016-03-01

    Polar bears are at the top of the Arctic marine food chain and are subject to exposure and bioaccumulation of environmental chemicals of concern such as polybrominated diphenyl ethers (PBDEs), which were widely used as flame retardants. The aim of the present study was to evaluate the in vitro oxidative metabolism of 2,2',4,4'-tetrabrominated diphenyl ether (BDE-47) and 2,2',4,4',5-pentabrominated diphenyl ether (BDE-99) by polar bear liver microsomes. The identification and quantification of the hydroxy-brominated diphenyl ethers formed were assessed using an ultra-high performance liquid chromatography-tandem mass spectrometry-based method. Incubation of BDE-47 with archived individual liver microsomes, prepared from fifteen polar bears from northern Canada, produced a total of eleven hydroxylated metabolites, eight of which were identified using authentic standards. The major metabolites were 4'-hydroxy-2,2',4,5'-tetrabromodiphenyl ether and 5'-hydroxy-2,2',4,4'-tetrabromodiphenyl ether. Incubation of BDE-99 with polar bear liver microsomes produced a total of eleven hydroxylated metabolites, seven of which were identified using authentic standards. The major metabolites were 2,4,5-tribromophenol and 4-hydroxy-2,2',3,4',5-pentabromodiphenyl ether. Among the CYP specific antibodies tested, anti-rat CYP2B was found to be the most active in inhibiting the formation of hydroxylated metabolites of both BDE-47 and BDE-99, indicating that CYP2B was the major CYP enzyme involved in the oxidative biotransformation of these two congeners. Our study shows that polar bears are capable of forming multiple hydroxylated metabolites of BDE-47 and BDE-99 in vitro and demonstrates the role of CYP2B in the biotransformation and possibly in the toxicity of BDE-47 and BDE-99 in polar bears. PMID:26745384

  15. Gas-uptake pharmacokinetics and biotransformation of 1,1-dichloro-1-fluoroethane (HCFC-141b).

    PubMed

    Loizou, G D; Anders, M W

    1993-01-01

    A physiologically based pharmacokinetic model was used to determine the in vivo metabolic constants of the candidate chlorofluorocarbon replacement 1,1-dichloro-1-fluoroethane (HCFC-141b). Rats were exposed by inhalation to HCFC-141b concentrations ranging from 1,000 to 10,000 ppm. Uptake studies of HCFC-141b in the rat indicated the involvement of saturable and first-order components. The in vivo metabolic constants for HCFC-141b were: KM = 7.0 mg liter-1 (59.9 mumol liter-1), Vmax = 0.2 mg kg-1 hr-1 (1.71 mumol kg-1 hr-1), and k = 0.5 hr-1. In rats exposed to HCFC-141b, 2,2-dichloro-2-fluoroethanol was excreted in the urine as its glucuronide conjugate, and the rate of 2,2-dichloro-2-fluoroethanol excretion increased linearly with increasing HCFC-141b exposure concentrations. Diallyl sulfide, a selective, mechanism-based inhibitor of cytochrome P-450 2E1, inhibited the metabolism of HCFC-141b, as indicated by a decreased uptake of HCFC-141b and by a lowered urinary excretion of 2,2-dichloro-2-fluoroethanol in diallyl-sulfide-treated rats. In vitro biotransformation studies with microsomes from rats treated with pyridine, an inducer of cytochrome P-450 2E1, confirmed that cytochrome P-450 2E1 is involved in the metabolism of HCFC-141b. The in vitro metabolic rate constants for the biotransformation of HCFC-141b to 2,2-dichloro-2-fluoroethanol were: KM = 0.39 +/- 0.11 mM and Vmax = 2.08 +/- 0.23 nmol mg protein-1 hr-1.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8104122

  16. Simultaneous extraction and biotransformation process to obtain high bioactivity phenolic compounds from Brazilian citrus residues.

    PubMed

    Madeira, Jose Valdo; Macedo, Gabriela Alves

    2015-01-01

    Recent studies have pointed to a reduction in the incidence of some cancers, diabetes, and neuro-degenerative diseases as a result of human health benefits from flavanones. Currently, flavanones are obtained by chemical synthesis or extraction from plants, and these processes are only produced in the glycosylated form. An interesting environmentally friendly alternative that deserves attention regarding phenolic compound production is the simultaneous extraction and biotransformation of these molecules. Orange juice consumption has become a worldwide dietary habit and Brazil is the largest producer of orange juice in the world. Approximately half of the citrus fruit is discarded after the juice is processed, thus generating large amounts of residues (peel and pectinolytic material). Hence, finding an environmentally clean technique to extract natural products and bioactive compounds from different plant materials has presented a challenging task over the last decades. The aim of this study was to obtain phenolics from Brazilian citrus residues with high bioactivity, using simultaneous extraction (cellulase and pectinase) and biotransformation (tannase) by enzymatic process. The highest hesperetin, naringenin and ellagic acid production in the experiment were 120, 80, and 11,250 µg g(-1), respectively, at 5.0 U mL(-1) of cellulase and 7.0 U mL(-1) of tannase at 40°C and 200 rpm. Also, the development of this process generated an increase of 77% in the total antioxidant capacity. These results suggest that the bioprocess obtained innovative results where the simultaneous enzymatic and biotransformatic extracted flavanones from agro-industrial residues was achieved without the use of organic solvents. The methodology can therefore be considered a green technology.

  17. Evaluation of hepatic biotransformation of polybrominated diphenyl ethers in the polar bear (Ursus maritimus).

    PubMed

    Krieger, Lisa K; Szeitz, András; Bandiera, Stelvio M

    2016-03-01

    Polar bears are at the top of the Arctic marine food chain and are subject to exposure and bioaccumulation of environmental chemicals of concern such as polybrominated diphenyl ethers (PBDEs), which were widely used as flame retardants. The aim of the present study was to evaluate the in vitro oxidative metabolism of 2,2',4,4'-tetrabrominated diphenyl ether (BDE-47) and 2,2',4,4',5-pentabrominated diphenyl ether (BDE-99) by polar bear liver microsomes. The identification and quantification of the hydroxy-brominated diphenyl ethers formed were assessed using an ultra-high performance liquid chromatography-tandem mass spectrometry-based method. Incubation of BDE-47 with archived individual liver microsomes, prepared from fifteen polar bears from northern Canada, produced a total of eleven hydroxylated metabolites, eight of which were identified using authentic standards. The major metabolites were 4'-hydroxy-2,2',4,5'-tetrabromodiphenyl ether and 5'-hydroxy-2,2',4,4'-tetrabromodiphenyl ether. Incubation of BDE-99 with polar bear liver microsomes produced a total of eleven hydroxylated metabolites, seven of which were identified using authentic standards. The major metabolites were 2,4,5-tribromophenol and 4-hydroxy-2,2',3,4',5-pentabromodiphenyl ether. Among the CYP specific antibodies tested, anti-rat CYP2B was found to be the most active in inhibiting the formation of hydroxylated metabolites of both BDE-47 and BDE-99, indicating that CYP2B was the major CYP enzyme involved in the oxidative biotransformation of these two congeners. Our study shows that polar bears are capable of forming multiple hydroxylated metabolites of BDE-47 and BDE-99 in vitro and demonstrates the role of CYP2B in the biotransformation and possibly in the toxicity of BDE-47 and BDE-99 in polar bears.

  18. The biotransformation of brewer's spent grain into biogas by anaerobic microbial communities.

    PubMed

    Malakhova, Dina V; Egorova, Maria A; Prokudina, Ljuba I; Netrusov, Alexander I; Tsavkelova, Elena A

    2015-12-01

    The present study reports on the biotransformation of the brewer's spent grain (BSG) in co-digestion with Jerusalem artichoke (JA, Helianthus tuberosus L.) phytomass by thermophilic (+55 °C) and mesophilic (+30 °C) anaerobic methanogenic communities. BSG is a by-product of the beer-brewing process generated in large amounts, in which utilization provokes a negative effect on the environment. In this study, we will show an effective conversion of BSG into biogas by selected microbial communities, obtained from different sources (animal manure and previously isolated microbial consortia). The stimulation of methanogenesis was reached by the co-digestion of JA's phytomass (stem and leaves). The optimized conditions for microbial stable cultivation included the use of nutrient medium, containing yeast extract and trace element solution. The optimal BSG concentration in biogas production was 50 and 100 g L(-1). Under thermophilic conditions, the maximum total methane production reached 64%, and it comprised around 6-8 and 9-11 of L CH4 per 100 g of fermented BSG without and with co-digested JA, respectively, when the fresh inoculum was added. Although, after a year of re-cultivation, the values reduced to around 6-7, and 6-10 L CH4/100 g BSG, correspondingly, the selected microbial communities showed effective biotransformation of BSG. The supplementation of soil with the residual fermented BSG (10%, w/w) resulted in the promotion of lettuce (Lepidium sativum L.) growth. The results obtained demonstrate a potential for complete BSG utilization via biogas production and application as a soil additive. PMID:26399858

  19. Employability of IT Graduates from the Industry's Perspective: A Case Study in Turkey

    ERIC Educational Resources Information Center

    Turhan, Cigdem; Akman, Ibrahim

    2013-01-01

    The qualifications that constitute the employability and identity of graduates are viewed differently by the academic community and the industry. Currently, it is observed for Information Technologies (IT) sector that the demands of the industry are not always satisfied by the perceived standards of the graduates. To provide feedback to the…

  20. Many Paths to Skilled Employment: A Reverse Tracer Study of Seven Occupations in Colombia.

    ERIC Educational Resources Information Center

    Ziderman, Adrian; Horn, Robin

    1995-01-01

    Employs reverse tracer techniques to identify alternative training paths for selected skilled and semiskilled occupations in Colombia. Shows that workers pursue various alternative training paths to acquire essential occupational skills. Strong public intervention in training markets should be discouraged, as choices would be narrowed and the…

  1. The Hartford Study of Supported Employment for Persons With Severe Mental Illness

    ERIC Educational Resources Information Center

    Mueser, Kim T.; Clark, Robin E.; Haines, Michael; Drake, Robert E.; McHugo, Gregory J.; Bond, Gary R.; Essock, Susan M.; Becker, Deborah R.; Wolfe, Rosemarie

    2004-01-01

    The authors compared 3 approaches to vocational rehabilitation for severe mental illness (SMI): the individual placement and support (IPS) model of supported employment, a psychosocial rehabilitation (PSR) program, and standard services. Two hundred four unemployed clients (46% African American, 30% Latino) with SMI were randomly assigned to IPS,…

  2. Engineering Curriculum Development: Balancing Employer Needs and National Interest--A Case Study.

    ERIC Educational Resources Information Center

    Buniyamin, Norlida; Mohamad, Zainuddin

    The Faculty of Mechanical Engineering at the University Teknologi MARA, Malaysia, developed an undergraduate-level engineering curriculum that balances national interests with those of employers and academics. The curriculum was based on materials posted at the Internet sites of universities in the United States, United Kingdom, and Malaysia…

  3. College Student Employment and Drinking: A Daily Study of Work Stressors, Alcohol Expectancies, and Alcohol Consumption

    PubMed Central

    Butler, Adam B.; Dodge, Kama D.; Faurote, Eric J.

    2010-01-01

    We examined the within-person relationships between daily work stressors and alcohol consumption over 14 consecutive days in a sample of 106 employed college students. Using a tension reduction theoretical framework, we predicted that exposure to work stressors would increase alcohol consumption by employed college students, particularly for men and those with stronger daily expectancies about the tension reducing properties of alcohol. After controlling for day of the week, we found that hours worked were positively related to number of drinks consumed. Workload was unrelated to alcohol consumption, and work-school conflict was negatively related to consumption, particularly when students expressed strong beliefs in the tension reducing properties of alcohol. There was no evidence that the effects of work stressors were moderated by gender. The results illustrate that employment during the academic year plays a significant role in college student drinking and suggest that the employment context may be an appropriate intervention site to address the problem of student drinking. PMID:20604635

  4. Is temporary employment damaging to health? A longitudinal study on Italian workers.

    PubMed

    Pirani, Elena; Salvini, Silvana

    2015-01-01

    Working conditions have changed dramatically over recent decades in all the countries of European Union: permanent full-time employment characterized by job security and a stable salary is replaced more and more by temporary work, apprenticeship contracts, casual jobs and part-time work. The consequences of these changes on the general well-being of workers and their health represent an increasingly important path of inquiry. We add to the debate by answering the question: are Italian workers on temporary contracts more likely to suffer from poor health than those with permanent jobs? Our analysis is based on a sample of men and women aged 16-64 coming from the Italian longitudinal survey 2007-2010 of the European Union Statistics on Income and Living Conditions. We use the method of inverse-probability-of-treatment weights to estimate the causal effect of temporary work on self-rated health, controlling for selection effects. Our major findings can be summarized as follows: firstly, we show a negative association between temporary employment and health that results from a statistical causal effect in the work-to-health direction, and does not trivially derive from a selection of healthier individuals in the group of people who find permanent jobs (selection effect). Secondly, we find that temporary employment becomes particularly negative for the individual's health when it is prolonged over time. Thirdly, whereas temporary employment does not entail significant adverse consequences for men, the link between temporary employment and health is strongly harmful for Italian women. PMID:25461869

  5. Illegal Aliens: Their Employment and Employers.

    ERIC Educational Resources Information Center

    Chiswick, Barry R.

    A study examined various characteristics of the employment of illegal aliens, including wages, job training, job mobility, workplace conditions, and employer characteristics. The study was largely based on data transcribed from a sample of Immigration and Naturalization Service apprehension reports on illegal aliens in the Chicago (Illinois)…

  6. Toward a Mediation Model of Employability Enhancement: A Study of Employee-Supervisor Pairs in the Building Sector

    ERIC Educational Resources Information Center

    van der Heijden, Beatrice I. J. M.; Bakker, Arnold B.

    2011-01-01

    This study examines whether jobs that enable competence development and a constructive leadership style enhance workers' employability or career potential through their assumed positive relationship with work-related flow (absorption, work enjoyment, and intrinsic work motivation). The authors conducted an explorative study with 303 pairs of…

  7. Wider Opportunities: Combining Literacy and Employment Training for Women. Executive Summary of the Female Single Parent Literacy Project Case Studies.

    ERIC Educational Resources Information Center

    Hirschoff, Paula

    This report contains summaries of case studies of five literacy projects for women conducted under the auspices of Wider Opportunities for Women's Female Single Parent Literacy Project. The programs described in the case studies are the following: (1) Non-Traditional Employment for Women, New York City; (2) Access for Women: Expanding Options for…

  8. A Family Music Project in the North of England: A Study of the Pedagogical Methodologies Employed and the Outcomes Achieved

    ERIC Educational Resources Information Center

    Bates, Christine

    2012-01-01

    This article examines learning outcomes in relation to the pedagogical methodologies employed in a community music project involving families. The research was designed with three stages. In the first stage case studies of existing family music projects were undertaken. In the second stage findings from the case studies were applied in the design…

  9. Higher Education and Graduate Employment in India. A Summary of Three Case Studies. IIEP Research Report No. 64.

    ERIC Educational Resources Information Center

    Carnoy, Martin

    The relationship between higher education and the economy in India, the labor market for college graduates, and the role of the public sector in reducing unemployment of college graduates were assessed in three studies. A case study in the State of West Bengal related the development of higher education with the employment needs of the country…

  10. Understanding the Relationships among PISA Scores, Economic Growth and Employment in Different Sectors: A Cross-Country Study

    ERIC Educational Resources Information Center

    Cheung, Hoi Yan; Chan, Alex W. H.

    2008-01-01

    This study investigates the relationship between Program for International Student Assessment (PISA) scores in mathematics, science and reading and the employment rates in the following four economic activities: research and development, agriculture, industry, and service industries. Thirty-three countries were included in the study, and most…

  11. Barriers to Employability of Persons with Handicaps: A Bi-National Study in the United States and Israel. Executive Summary.

    ERIC Educational Resources Information Center

    Newman, Edward; And Others

    A study compared the barriers to employment facing handicapped persons in Israel and the United States. Five vocational rehabilitation centers (two in the United States and three in Israel) were examined. Each was studied in terms of the type of center, population served, goals, nature and scope of services provided, sources of income, staff and…

  12. Fungal Bioweathering of Mimetite and a General Geomycological Model for Lead Apatite Mineral Biotransformations

    PubMed Central

    Ceci, Andrea; Kierans, Martin; Hillier, Stephen; Persiani, Anna Maria

    2015-01-01

    Fungi play important roles in biogeochemical processes such as organic matter decomposition, bioweathering of minerals and rocks, and metal transformations and therefore influence elemental cycles for essential and potentially toxic elements, e.g., P, S, Pb, and As. Arsenic is a potentially toxic metalloid for most organisms and naturally occurs in trace quantities in soil, rocks, water, air, and living organisms. Among more than 300 arsenic minerals occurring in nature, mimetite [Pb5(AsO4)3Cl] is the most stable lead arsenate and holds considerable promise in metal stabilization for in situ and ex situ sequestration and remediation through precipitation, as do other insoluble lead apatites, such as pyromorphite [Pb5(PO4)3Cl] and vanadinite [Pb5(VO4)3Cl]. Despite the insolubility of mimetite, the organic acid-producing soil fungus Aspergillus niger was able to solubilize mimetite with simultaneous precipitation of lead oxalate as a new mycogenic biomineral. Since fungal biotransformation of both pyromorphite and vanadinite has been previously documented, a new biogeochemical model for the biogenic transformation of lead apatites (mimetite, pyromorphite, and vanadinite) by fungi is hypothesized in this study by application of geochemical modeling together with experimental data. The models closely agreed with experimental data and provided accurate simulation of As and Pb complexation and biomineral formation dependent on, e.g., pH, cation-anion composition, and concentration. A general pattern for fungal biotransformation of lead apatite minerals is proposed, proving new understanding of ecological implications of the biogeochemical cycling of component elements as well as industrial applications in metal stabilization, bioremediation, and biorecovery. PMID:25979898

  13. Fungal Bioweathering of Mimetite and a General Geomycological Model for Lead Apatite Mineral Biotransformations.

    PubMed

    Ceci, Andrea; Kierans, Martin; Hillier, Stephen; Persiani, Anna Maria; Gadd, Geoffrey Michael

    2015-08-01

    Fungi play important roles in biogeochemical processes such as organic matter decomposition, bioweathering of minerals and rocks, and metal transformations and therefore influence elemental cycles for essential and potentially toxic elements, e.g., P, S, Pb, and As. Arsenic is a potentially toxic metalloid for most organisms and naturally occurs in trace quantities in soil, rocks, water, air, and living organisms. Among more than 300 arsenic minerals occurring in nature, mimetite [Pb5(AsO4)3Cl] is the most stable lead arsenate and holds considerable promise in metal stabilization for in situ and ex situ sequestration and remediation through precipitation, as do other insoluble lead apatites, such as pyromorphite [Pb5(PO4)3Cl] and vanadinite [Pb5(VO4)3Cl]. Despite the insolubility of mimetite, the organic acid-producing soil fungus Aspergillus niger was able to solubilize mimetite with simultaneous precipitation of lead oxalate as a new mycogenic biomineral. Since fungal biotransformation of both pyromorphite and vanadinite has been previously documented, a new biogeochemical model for the biogenic transformation of lead apatites (mimetite, pyromorphite, and vanadinite) by fungi is hypothesized in this study by application of geochemical modeling together with experimental data. The models closely agreed with experimental data and provided accurate simulation of As and Pb complexation and biomineral formation dependent on, e.g., pH, cation-anion composition, and concentration. A general pattern for fungal biotransformation of lead apatite minerals is proposed, proving new understanding of ecological implications of the biogeochemical cycling of component elements as well as industrial applications in metal stabilization, bioremediation, and biorecovery.

  14. Biotransformation of the Mycotoxin Deoxynivalenol in Fusarium Resistant and Susceptible Near Isogenic Wheat Lines

    PubMed Central

    Kluger, Bernhard; Bueschl, Christoph; Lemmens, Marc; Michlmayr, Herbert; Malachova, Alexandra; Koutnik, Andrea; Maloku, Imer; Berthiller, Franz; Adam, Gerhard; Krska, Rudolf; Schuhmacher, Rainer

    2015-01-01

    In this study, a total of nine different biotransformation products of the Fusarium mycotoxin deoxynivalenol (DON) formed in wheat during detoxification of the toxin are characterized by liquid chromatography—high resolution mass spectrometry (LC-HRMS). The detected metabolites suggest that DON is conjugated to endogenous metabolites via two major metabolism routes, namely 1) glucosylation (DON-3-glucoside, DON-di-hexoside, 15-acetyl-DON-3-glucoside, DON-malonylglucoside) and 2) glutathione conjugation (DON-S-glutathione, “DON-2H”-S-glutathione, DON-S-cysteinyl-glycine and DON-S-cysteine). Furthermore, conjugation of DON to a putative sugar alcohol (hexitol) was found. A molar mass balance for the cultivar ‘Remus’ treated with 1 mg DON revealed that under the test conditions approximately 15% of the added DON were transformed into DON-3-glucoside and another 19% were transformed to the remaining eight biotransformation products or irreversibly bound to the plant matrix. Additionally, metabolite abundance was monitored as a function of time for each DON derivative and was established for six DON treated wheat lines (1 mg/ear) differing in resistance quantitative trait loci (QTL) Fhb1 and/or Qfhs.ifa-5A. All cultivars carrying QTL Fhb1 showed similar metabolism kinetics: Formation of DON-Glc was faster, while DON-GSH production was less efficient compared to cultivars which lacked the resistance QTL Fhb1. Moreover, all wheat lines harboring Fhb1 showed significantly elevated D3G/DON abundance ratios. PMID:25775425

  15. Fungal Bioweathering of Mimetite and a General Geomycological Model for Lead Apatite Mineral Biotransformations.

    PubMed

    Ceci, Andrea; Kierans, Martin; Hillier, Stephen; Persiani, Anna Maria; Gadd, Geoffrey Michael

    2015-08-01

    Fungi play important roles in biogeochemical processes such as organic matter decomposition, bioweathering of minerals and rocks, and metal transformations and therefore influence elemental cycles for essential and potentially toxic elements, e.g., P, S, Pb, and As. Arsenic is a potentially toxic metalloid for most organisms and naturally occurs in trace quantities in soil, rocks, water, air, and living organisms. Among more than 300 arsenic minerals occurring in nature, mimetite [Pb5(AsO4)3Cl] is the most stable lead arsenate and holds considerable promise in metal stabilization for in situ and ex situ sequestration and remediation through precipitation, as do other insoluble lead apatites, such as pyromorphite [Pb5(PO4)3Cl] and vanadinite [Pb5(VO4)3Cl]. Despite the insolubility of mimetite, the organic acid-producing soil fungus Aspergillus niger was able to solubilize mimetite with simultaneous precipitation of lead oxalate as a new mycogenic biomineral. Since fungal biotransformation of both pyromorphite and vanadinite has been previously documented, a new biogeochemical model for the biogenic transformation of lead apatites (mimetite, pyromorphite, and vanadinite) by fungi is hypothesized in this study by application of geochemical modeling together with experimental data. The models closely agreed with experimental data and provided accurate simulation of As and Pb complexation and biomineral formation dependent on, e.g., pH, cation-anion composition, and concentration. A general pattern for fungal biotransformation of lead apatite minerals is proposed, proving new understanding of ecological implications of the biogeochemical cycling of component elements as well as industrial applications in metal stabilization, bioremediation, and biorecovery. PMID:25979898

  16. Hepatic metabolism, phase I and II biotransformation enzymes in Atlantic salmon (Salmo Salar, L) during a 12 week feeding period with graded levels of the synthetic antioxidant, ethoxyquin.

    PubMed

    Berdikova Bohne, Victoria J; Hamre, Kristin; Arukwe, Augustine

    2007-05-01

    The synthetic antioxidant ethoxyquin (EQ) is a widely used additive in animal feeds, including farmed fish feed. The use of EQ as food additive is prohibited and it is also undesirable in farmed meat and fish products. The possible negative aspects of EQ in fish feeds, such as modulation of hepatic detoxifying enzymes and possible effects through "carry-over" to edible parts of fish are not known. In addition, the subsequent consequences for human consumers have not been previously studied. In the present work, the alteration in gene and protein expression patterns, and catalytic activities of phase I and II hepatic biotransformation enzymes due to prolonged exposure to graded levels of dietary EQ in the range of 11-1800 mg EQ/kg feed were studied. The kinetics of parent EQ and its major metabolite, ethoxyquin dimer (EQDM) was also studied. In general two weeks seem to be the critical point in the entire toxicological response of salmon to dietary consumed EQ. Biotransformation of EQ to EQDM is shown to be a rapid process. However, the decrease in biotransformation rate results in the accumulation of EQ metabolites, high concentration of which was postulated to alter translation and post-translational modification of CYP3A, GST and UDPGT at feeding day 14 and 42, with subsequent decreases in the biotransformation of consumed EQ. Decrease in the biotransformation of consumed EQ produced the retention of un-metabolized EQ rather than metabolites in salmon liver. This may be considered as undesirable effect, since it could lead to the transport and accumulation in other organs and edible tissues. It may also cause a new wave of biotransformation with formation of metabolites inhibiting detoxifying enzymes. In general, these processes may prolong the excretion of dietary EQ from the fish body and produce EQ-derived residues in the ready-to-consume salmon or fish products. These EQ residues may have higher toxicological effects for human consumers than the parent

  17. Studies on preparation of medium fat liquid dairy whitener from buffalo milk employing ultrafiltration process.

    PubMed

    Khatkar, Sunil Kumar; Gupta, Vijay Kumar; Khatkar, Anju Boora

    2014-09-01

    A study was conducted to develop good quality medium fat liquid dairy whitener from buffalo milk employing ultrafiltration (UF) process. The buffalo skim milk was UF concentrated to 4.05 to 4.18 (23.63 ± 0.30 % TS) fold and standardized to 10 % fat (on Dry Matter Basis) (i.e. formulation) and homogenized at 175.76 kg/cm(2). The addition of 0.4 % mixture of monosodium and disodium phosphate (2:1 w/w) improved the heat stability of homogenized formulation to an optimum of 66 min. The bland flavour of homogenized formulation with added 0.4 % mixture of monosodium phosphate and disodium phosphate (2:1 w/w) and 18 % sugar (on DMB) (i.e. medium fat liquid dairy whitener) was improved significantly (P < 0.01) with the addition of 0.2 % potassium chloride, but heat stability of medium fat liquid dairy whitener got reduced substantially (i.e. 19 min). With subsequent heat treatment to 85 °C for 5 min, heat stability of medium fat liquid dairy whitener got improved to reasonable level of 27 min. Whitening ability in terms of L* value of medium fat liquid dairy whitener in both tea and coffee was significantly (P < 0.01) better when homogenized at 175.76 kg/cm(2) vis-à-vis 140.61 kg/cm(2). Standardized medium fat liquid dairy whitener had significantly (P < 0.01) greater protein content (i.e. approximately 2.43 times) compared to market dairy whitener samples. At 2 % solids level, standardized medium fat liquid dairy whitener in tea/coffee fetched significantly (P < 0.01) better sensory attributes and instrumental whitening ability compared to market sample at 3 % solids level. There could be clear 33 % solids quantity saving in case of developed product compared to market dairy whitener sample.

  18. Engaging Employers?

    ERIC Educational Resources Information Center

    Hillier, Yvonne

    2008-01-01

    A key factor in the successful development of workplace learning is employer engagement (Leitch, 2006; DfES, 2007). However, despite numerous approaches by government in the United Kingdom to bring together employers, providers and learners so that economic success is generated by a skilled and flexible workforce, there continue to be challenges…

  19. Maternal Employment

    ERIC Educational Resources Information Center

    Clark, Sam

    1975-01-01

    The overwhelming evidence from years of research is that maternal employment, by itself, has little influence on the behaviors of children. More relevant issues are: mother's reasons for working, family's acceptance of mother's employment, quality of substitute child care, family's social and emotional health, and economic conditions. (Author/AJ)

  20. Industry Employment

    ERIC Educational Resources Information Center

    Occupational Outlook Quarterly, 2010

    2010-01-01

    This article illustrates projected employment change from an industry perspective over the 2008-2018 decade. Workers are grouped into an industry according to the type of good produced or service provided by the establishment in which they work. Industry employment projections are shown in terms of numeric change (growth or decline in the total…

  1. Industry Employment

    ERIC Educational Resources Information Center

    Occupational Outlook Quarterly, 2012

    2012-01-01

    This article illustrates projected employment change by industry and industry sector over 2010-20 decade. Workers are grouped into an industry according to the type of good produced or service provided by the establishment for which they work. Industry employment projections are shown in terms of numeric change (growth or decline in the total…

  2. Study of structural modification of sugarcane bagasse employing hydrothermal treatment followed by atmospheric pressure plasmas treatment

    NASA Astrophysics Data System (ADS)

    Amorim, Jayr; Pimenta, Maria Teresa; Gurgel, Leandro; Squina, Fabio; Souza-Correa, Jorge; Curvelo, Antonio

    2009-10-01

    Nowadays, the cellulosic ethanol is an important alternative way to many liquid biofuels using renewable biomass rich in polysaccharides. To be used as feedstock for ethanol production, the bagasse needs to be pretreated in order to expose its main constitutive. The present work proposes the use of different pretreatment processes to better expose the cellulose for hydrolysis and fermentation. In the present paper the sugarcane bagasse was submitted to a hydrothermal pretreatment followed by atmospheric pressure plasmas (APPs). An RF microplasma torch was employed as APPs in Ar and Ar/O2 mixing. The bagasse was treated in discharge and post-discharge regions. The position and time of treatment was varied as well as the gas mixture. The quantity of polysaccharides was determined by using high performance liquid chromatography. It was observed the release of a fraction of the hemicelluloses in the sugarcane bagasse. Modifications in the surface of the sugarcane fibers were monitored by employing scanning electron microscopy.

  3. Comparing health-related quality of life of employed women and housewives: a cross sectional study from southeast Iran

    PubMed Central

    2012-01-01

    Background Quality of life differs for different people in different situations and is related to one's self-satisfaction with life. Considering the role of women in family and social health and the specific cultural characteristics of our province, we aimed to compare the quality of life of employed women with housewives in Zahedan, Iran. Methods This cross-sectional study was carried out during 2009–2010 in Zahedan, Iran. The sample consisted of 110 housewives and 110 employed women selected randomly from ten health care centers. Health-related quality of life was assessed using the SF-36. Analysis of covariance (ANCOVA) was used to compare quality of life in housewives and employed women while controlling for age, education and income. Results The mean (±SD) age of participants was 33.87± 8.95 years. Eighty-eight women (40%) had a university degree with a mean (±SD) official education of 10.8 (±4.9) years. The results indicated that employed women scored higher than housewives in all measures except for physical functioning. The differences were found to be remarkable for vitality, mental health and role emotional. However, after controlling for age, education and family income, none of differences reached significant level. Conclusion After controlling for potential confounders, the findings from this study indicated that there were no significant differences in quality of life between employed women and housewives. However, employed women scored higher on the SF-36, especially on the role emotional, vitality, and mental health. The findings suggest that associations exist between some aspects of health-related quality of life and employment. Indeed improving health-related quality of life among housewives seems essential. PMID:23173572

  4. Study of Organic Matter in Soils of the Amazon Region Employing Laser Induced Fluorescence Spectroscopy

    NASA Astrophysics Data System (ADS)

    Tadini, Amanda Maria; Nicolodelli, Gustavo; Mounier, Stéphane; Montes, Célia Regina; Marcondes Bastos Pereira Milori, Débora

    2014-05-01

    In the face of climate change and increasing CO2 levels in the atmosphere, the global carbon cycle, soil organic carbon (SOC) sequestration, and the role of different world biomes as potential sources and sinks of carbon are receiving increasing attention. Carbon quantification is an important environmental indicator, but the structure of organic matter is also important because is related to carbon stability. The synthesis of soil organic matter (SOM), as presented in soils of forest vegetation, can be originated from condensation polymeric polyphenols and quinones that are responsible for controlling the main physical-chemical properties of soils. These systems are present in humic substances, representing the major fluorophore of SOM[1-3]. Abiotic factors, such as soil texture, use and occupation of soil, can influence on the process of SOM formation, molecular structure and in its humification index[4]. Laser Induced Fluorescence Spectroscopy (LIFS) have become a promising technique for assessing humification index of SOM (HLIFS). In this context, the aim of this study was to analyze the humification index of the SOM in the region of Barcelos (Amazon) employing LIFS. The study area was the region of Barcelos, close the river Demeni. The whose vegetation distribution in this area, is two biomes the Dense Ombrophylous Forest (DPQD) and Campinarana (DPQT), with areas of edaphic contacts between these two phytophysiognomies, which ranged from Open field (FDE) to closed Depression (DPQ). Preliminary results showed that the area closed Depression (DPQ) there was a continuous gradient of humification with increasing soil depth. A similar behavior was verified for area Forest (DPQD), where the highest values of HLIFS were obtained between the four points analyzed, indicating the magnitude of the molecular recalcitrance this organic matter in this area. The results obtained for area Campinarana (DPQT) and Open field (FDE) showed an opposite behavior. These points there

  5. Biotransformation of 6:2 fluorotelomer alcohol (6:2 FTOH) by a wood-rotting fungus.

    PubMed

    Tseng, Nancy; Wang, Ning; Szostek, Bogdan; Mahendra, Shaily

    2014-04-01

    Biotransformation of 6:2 FTOH [F(CF2)6CH2CH2OH] by the white-rot fungus, Phanerochaete chrysosporium, was investigated in laboratory studies. 6:2 FTOH is a raw material increasingly being used to replace products that can lead to long-chain perfluoroalkyl carboxylic acids (PFCAs, ≥ 8 carbons). During a product's life cycle and after final disposal, 6:2 FTOH-derived compounds may be released into the environment and potentially biotransformed. In this study, P. chrysosporium transformed 6:2 FTOH to perfluorocarboxylic acids (PFCAs), polyfluorocarboxylic acids, and transient intermediates within 28 days. 5:3 Acid [F(CF2)5CH2CH2COOH] was the most abundant transformation product, accounting for 32-43 mol % of initially applied 6:2 FTOH in cultures supplemented with lignocellulosic powder, yeast extract, cellulose, and glucose. PFCAs, including perfluoropentanoic (PFPeA) and perfluorohexanoic (PFHxA) acids, accounted for 5.9 mol % after 28-day incubation. Furthermore, four new transformation products as 6:2 FTOH conjugates or 5:3 acid analogues were structurally confirmed. These results demonstrate that P. chrysosporium has the necessary biochemical mechanisms to drive 6:2 FTOH biotransformation pathways toward more degradable polyfluoroalkylcarboxylic acids, such as 5:3 acid, with lower PFCA yields compared to aerobic soil, sludge, and microbial consortia. Since bacteria and fungi appear to contribute differently toward the environmental loading of FTOH-derived PFCAs and polyfluorocarboxylic acids, wood-rotting fungi should be evaluated as potential candidates for the bioremediation of wastewater and groundwater contaminated with fluoroalkyl substances.

  6. Biotransformation of Tributyltin chloride by Pseudomonas stutzeri strain DN2

    PubMed Central

    Khanolkar, Dnyanada S.; Naik, Milind Mohan; Dubey, Santosh Kumar

    2014-01-01

    A bacterial isolate capable of utilizing tributyltin chloride (TBTCl) as sole carbon source was isolated from estuarine sediments of west coast of India and identified as Pseudomonas stutzeri based on biochemical tests and Fatty acid methyl ester (FAME) analysis. This isolate was designated as strain DN2. Although this bacterial isolate could resist up to 3 mM TBTCl level, it showed maximum growth at 2 mM TBTCl in mineral salt medium (MSM). Pseudomonas stutzeri DN2 exposed to 2 mM TBTCl revealed significant alteration in cell morphology as elongation and shrinkage in cell size along with roughness of cell surface. FTIR and NMR analysis of TBTCl degradation product extracted using chloroform and purified using column chromatography clearly revealed biotransformation of TBTCl into Dibutyltin dichloride (DBTCl2) through debutylation process. Therefore, Pseudomonas stutzeri strain DN2 may be used as a potential bacterial strain for bioremediation of TBTCl contaminated aquatic environmental sites. PMID:25763027

  7. Biotransformation of bergapten and xanthotoxin by Glomerella cingulata.

    PubMed

    Marumoto, Shinsuke; Miyazawa, Mitsuo

    2010-07-14

    The biotransformation of bergapten (1) by the fungus Glomerella cingulata gave the corresponding reduced acid, 6,7-furano-5-methoxy hydrocoumaric acid (2), a new compound. Xanthotoxin (3) was also converted to the corresponding reduced acid cnidiol b (4) and demethylated metabolite xanthotoxol (5) by G. cingulata. The structure of the new compound 2 was elucidated by high-resolution mass spectrometry, extensive NMR techniques, including (1)H NMR and (13)C NMR, (1)H-(1)H correlation spectroscopy, heteronuclear multiple quantum coherence, and heteonuclear multiple bond coherence. The methyl ester or methyl ether or methyl ester and ether derivatives of 2 and 4 were synthesized. All compounds were tested for the beta-secretase (BACE1) inhibitory activity in vitro. The methyl ester and ether derivative 8 was shown to possess BACE1 inhibitory activity, and a IC(50) value was 0.64 +/- 0.04 mM. PMID:20527746

  8. Biotransformation of sultopride in man and several animal species.

    PubMed

    Kobari, T; Namekawa, H; Kato, Y; Yamada, S

    1985-06-01

    The biotransformation of sultopride has been investigated in rat, rabbit, dog and man. In man sultopride was metabolically stable, and about 90% of an oral dose was excreted in urine unchanged and 4% as oxo-sultopride. Rat, rabbit and dog metabolized sultopride more extensively and excreted less than 40% of an oral dose of 14C-sultopride in urine. Four similar metabolites were excreted by the three animal species but the relative portions differed. The major radioactive component in rat urine was O-desmethyl sultopride, whereas oxo-sultopride and O-desmethyl sultopride were the major urinary metabolites in rabbit. Dog formed N-desethyl sultopride and oxo-sultopride as major urinary metabolites. The male rat excreted smaller amounts of unchanged sultopride in urine than did the female rat. The unchanged sultopride excreted in rat urine was increased slightly by repeated administration.

  9. Biotransformation of Microcystins in Eukaryotic Cells - Possible Future Research Directions.

    PubMed

    Pflugmacher, Stephan

    2016-01-01

    Due to eutrophication processes in our water bodies, cyanobacterial blooms can develop worldwide. Most of these blooms are toxic. The most prominent cyanobacterial toxins are the group of the microcystins, which are cyclic heptapeptides, currently with more than 100 congeners known. The biotransformation of microcystins starts with the conjugation to the cell internal tripeptide glutathione, catalysed by glutathione S-transferase enzymes. This conjugate is further broken down to a cysteine conjugate, enhancing the cell internal transport and excretion of the conjugated toxin from the organisms. Still many questions remain open, thinking on an obviously good working detoxification system on the one side and the often seen negative effects up to the death of humans on the other sides.

  10. Consequences of bile salt biotransformations by intestinal bacteria.

    PubMed

    Ridlon, Jason M; Harris, Spencer C; Bhowmik, Shiva; Kang, Dae-Joong; Hylemon, Phillip B

    2016-01-01

    Emerging evidence strongly suggest that the human "microbiome" plays an important role in both health and disease. Bile acids function both as detergents molecules promoting nutrient absorption in the intestines and as hormones regulating nutrient metabolism. Bile acids regulate metabolism via activation of specific nuclear receptors (NR) and G-protein coupled receptors (GPCRs). The circulating bile acid pool composition consists of primary bile acids produced from cholesterol in the liver, and secondary bile acids formed by specific gut bacteria. The various biotransformation of bile acids carried out by gut bacteria appear to regulate the structure of the gut microbiome and host physiology. Increased levels of secondary bile acids are associated with specific diseases of the GI system. Elucidating methods to control the gut microbiome and bile acid pool composition in humans may lead to a reduction in some of the major diseases of the liver, gall bladder and colon. PMID:26939849

  11. Biotransformation of sesquiterpenoids from liverworts by fungi and mammals.

    PubMed

    Asakawa, Yoshinori; Hashimoto, Toshihiro; Noma, Yoshiaki

    2010-05-01

    Biotransformation of sesquiterpenoids isolated from several liverworts using various fungi and mammals is summarized. Microorganisms introduce an oxygen atom at an allylic position to give secondary hydroxyl and keto groups. The cyclopentane ring is also oxidized to afford monoketo, and mono- and diols. Double bonds are also either reduced or oxidized to give either saturated compounds or epoxides, followed by hydrolysis to afford diols. The methyl group is oxidized to give a primary alcohol. Some fungi cleave the cyclopropane ring to form a 1,1-dimethyl group. These reactions precede stereo- and regiospecifically. Cytochrome P-450 is responsible for the introduction of an oxygen function into the substrates. The present methods are cheap, one step reactions, non-hazardous, and very useful for the production of some bioactive compounds from a large number of terpenoids found in liverworts and higher plants.

  12. Use of molecularly imprinted polymers in a biotransformation process.

    PubMed

    Ye, L; Ramström, O; Ansell, R J; Månsson, M O; Mosbach, K

    1999-09-20

    Molecularly imprinted polymers are highly stable and can be sterilised, making them ideal for use in biotransformation process. In this communication, we describe a novel application of molecularly imprinted polymers in an enzymatic reaction. The enzymatic condensation of Z-L-aspartic acid with L-phenylalanine methyl ester to give Z-L-Asp-L-Phe-OMe (Z-aspartame) was chosen as a model system to evaluate the applicability of using molecularly imprinted polymers to facilitate product formation. When the product-imprinted polymer is present, a considerable increase (40%) in product yield is obtained. Besides their use to enhance product yields, as demonstrated here, we suggest that imprinted polymers may also find use in the continuous removal of toxic compounds during biochemical reactions.

  13. Statistical media and process optimization for biotransformation of rice bran to vanillin using Pediococcus acidilactici.

    PubMed

    Kaur, Baljinder; Chakraborty, Debkumar

    2013-11-01

    An isolate of P. acidilactici capable of producing vanillin from rice bran was isolated from a milk product. Response Surface Methodology was employed for statistical media and process optimization for production of biovanillin. Statistical medium optimization was done in two steps involving Placket Burman Design and Central Composite Response Designs. The RSM optimized vanillin production medium consisted of 15% (w/v) rice bran, 0.5% (w/v) peptone, 0.1% (w/v) ammonium nitrate, 0.005% (w/v) ferulic acid, 0.005% (w/v) magnesium sulphate, and 0.1% (v/v) tween-80, pH 5.6, at a temperature of 37 degrees C under shaking conditions at 180 rpm. 1.269 g/L vanillin was obtained within 24 h of incubation in optimized culture medium. This is the first report indicating such a high vanillin yield obtained during biotransformation of ferulic acid to vanillin using a Pediococcal isolate.

  14. Oxidation of Secondary Alcohols by Duckweed: A Biotransformation Experiment for Undergraduate Students.

    ERIC Educational Resources Information Center

    Karfarski, Pawel; And Others

    1988-01-01

    Describes an experiment designed to use the ability of duckweed to convert the secondary hydroxyl moieties into ketone groups. Discusses the preparation of plant material, materials, procedures, and results for this biotransformation experiment for undergraduate students. (CW)

  15. COMPOUND-SPECIFIC STABLE ISOTOPE ANALYSIS TO DEMONSTRATE IN-SITU MTBE BIOTRANSFORMATION

    EPA Science Inventory

    Change of stable isotope composition of organic contaminants (isotopic fractionation) is a useful indicator of biotransformation. Most of applications to date are in the area of chlorinated solvents and recently BTEX, MTBE and TBA. Chemical reactions (biotic- and abiotic transfor...

  16. REDUCTIVE BIOTRANSFORMATION OF TETRACHLOROETHENE TO ETHENE DURING ANAEROBIC DEGRADATION OF TOLUENE: EXPERIMENTAL EVIDENCE AND KINETICS

    EPA Science Inventory

    Reductive biotransformation of tetrachloroethene (PCE) to ethene occurred during anaerobic degradation of toluene in an enrichment culture. Ethene was detected as a dominant daughter product of PCE dechlorination with negligible accumulation of other partially chlorinated ethenes...

  17. Three Measurable and Modifiable Enteric Microbial Biotransformations Relevant to Cancer Prevention and Treatment

    PubMed Central

    2014-01-01

    Interdisciplinary scientific evaluation of the human microbiota has identified three enteric microbial biotransformations of particular relevance for human health and well-being, especially cancer. Two biotransformations are counterproductive; one is productive. First, selective bacteria can reverse beneficial hepatic hydroxylation to produce toxic secondary bile acids, especially deoxycholic acid. Second, numerous bacterial species can reverse hepatic detoxification—in a sense, retoxify hormones and xeonobiotics—by deglucuronidation. Third, numerous enteric bacteria can effect a very positive biotransformation through the production of butyrate, a small chain fatty acid with anti-cancer activity. Each biotransformation is addressed in sequence for its relevance in representative gastrointestinal and extra-intestinal cancers. This is not a complete review of their connection with every type of cancer. The intent is to introduce the reader to clinically relevant microbial biochemistry plus the emerging evidence that links these to both carcinogenesis and treatment. Included is the evidence base to guide counseling for potentially helpful dietary adjustments. PMID:24891992

  18. The New Employment Contract?

    ERIC Educational Resources Information Center

    Levine, David I.

    2002-01-01

    In the classic employment contract, especially at large companies, wages were not strongly responsive to the labor market. Instead, individual companies had distinctive company wage levels and patterns. An exhaustive study of employers and employees in the United States and Japan examined whether the "old employment contract" has been replaced.…

  19. The Role of Job Resources in the Relation between Perceived Employability and Turnover Intention: A Prospective Two-Sample Study

    ERIC Educational Resources Information Center

    De Cuyper, Nele; Mauno, Saija; Kinnunen, Ulla; Makikangas, Anne

    2011-01-01

    We hypothesize that the relationship between perceived employability (PE) and turnover intention is stronger when job resources (job control, social support from the supervisor and colleagues) are low. Results from a prospective study one year apart were similar in samples of Finnish university (N = 1314) and hospital workers (N = 308). The…

  20. The Study of the Academic Employment and Graduate Enrollment Patterns and Trends of Women in Science and Engineering. Summary Report.

    ERIC Educational Resources Information Center

    Rose, Clare; And Others

    A study was undertaken of the employment and enrollment patterns of women scientists/engineers and graduate students in eight major scientific fields: engineering, physical sciences, environmental sciences, mathematical sciences, agricultural and biological sciences, medical sciences, psychology, and social sciences. The first part of the study…

  1. Creative and Stylistic Devices Employed by Children during a Storybook Narrative Task: A Cross-Cultural Study

    ERIC Educational Resources Information Center

    Gorman, Brenda K.; Fiestas, Christine E.; Pena, Elizabeth D.; Clark, Maya Reynolds

    2011-01-01

    Purpose: The purpose of this study was to analyze the effects of culture on the creative and stylistic features children employ when producing narratives based on wordless picture books. Method: Participants included 60 first- and second-grade African American, Latino American, and Caucasian children. A subset of narratives based on wordless…

  2. The Employment Effects of High-Technology: A Case Study of Machine Vision. Research Report No. 86-19.

    ERIC Educational Resources Information Center

    Chen, Kan; Stafford, Frank P.

    A case study of machine vision was conducted to identify and analyze the employment effects of high technology in general. (Machine vision is the automatic acquisition and analysis of an image to obtain desired information for use in controlling an industrial activity, such as the visual sensor system that gives eyes to a robot.) Machine vision as…

  3. Comparative Study of Vocational Nursing Curriculum and Employer Requirements. Update. Napa Valley College, October 1991-June 1992.

    ERIC Educational Resources Information Center

    Zylinski, Doris; And Others

    In 1991-92, a project was undertaken at Napa Valley College to update the college's 1990 Comparative Study of Vocational Nursing Curriculum and Employer Requirements, to develop a model articulation program for licensed nurses pursuing associate degrees, and to produce a guide for recruiting and retaining underrepresented groups in vocational…

  4. Employment of College Graduates in the Era of Universalized Higher Education: A Comparative Study by School Type and Discipline

    ERIC Educational Resources Information Center

    Ching-Pao, Chuang; Joanne, Hu J. H.

    2012-01-01

    The employment performance (including salaries, relevant to studies and job satisfaction) of college graduates from different school types and disciplines after the universalization of higher education in Taiwan was examined and a comparative analysis was conducted in this article. The findings were as follows: 1) "Medicine and health" and…

  5. Assessment of potential anaerobic biotransformation of organic pollutants in sediment caps.

    PubMed

    Smith, Anthony M; Kirisits, Mary Jo; Reible, Danny D

    2012-11-15

    In situ capping is a remedial approach for reducing the risk of biota exposure to sediment contaminants. Biotransformation of contaminants in sand-based sediment caps, rarely considered in sediment cap design, could further reduce the exposure risk. The anaerobic biotransformation of benzene, toluene, ethylbenzene, xylenes (BTEX), monochlorobenzene, dichlorobenzenes and naphthalene was evaluated with sediments from Onondaga Lake in dilute sediment slurries and in sand-capped sediment laboratory-scale columns. The percentage of sediment samples demonstrating biotransformation under anaerobic conditions in slurries incubated at 12°C was greatest for BTEX, followed by monochlorobenzene, 1,4-dichlorobenzene, 1,2-dichlorobenzene and 1,3-dichlorobenzene. Only toluene biotransformation was observed in sand cap columns. The rate of toluene biotransformation diminished over time, which might be due to inhibition caused by hydrogen from the experimental setup. Results suggest potential for the biotransformation of toluene, and possibly other pollutants, in sand-based sediment caps under anaerobic conditions at low temperatures.

  6. High-performance liquid chromatographic separation of the biotransformation products of oxaliplatin.

    PubMed

    Luo, F R; Yen, T Y; Wyrick, S D; Chaney, S G

    1999-03-19

    A novel single reversed-phase HPLC system was developed for separating oxaliplatin and its biotransformation products formed in rat plasma. The major stable biotransformation products of oxaliplatin formed in rat plasma were identified as Pt(dach)(Cys)2, Pt(dach)(Met) and free dach. The minor biotransformation products Pt(dach)Cl2, Pt(dach)(GSH) and Pt(dach)(GSH)2 could also be resolved from other Pt-dach complexes. Among these biotransformation products, the identification of Pt(dach)(Met) was further confirmed by LC-ESI-MS, and the identification of Pt(dach)(Cys)2, Pt(dach)(GSH), Pt(dach)(GSH)2 and free dach was confirmed by atomic absorption and double isotope labeling. This HPLC technique should prove useful for separating and identifying the biotransformation products of Pt-dach drugs such as oxaliplatin, ormaplatin and Pt(dach)(mal) in biological fluids. This will allow a more complete characterization of the pharmacokinetics and biotransformations of these Pt-dach drugs, which should in turn lead to a better understanding of the mechanisms leading to their toxicity and efficacy.

  7. Biotransformation at 10 C of di-n-butyl phthalate in subsurface microcosms

    SciTech Connect

    Chauret, C.; Inniss, W.E.; Mayfield, C.I.

    1996-09-01

    Di-n-butyl phthalate (DBP) was found to be transformed by microorganisms under aerobic and anaerobic conditions at 10 C in microcosms simulating the Canadian Forces Base (CFB) Borden subsurface environment. Biotransformation of DBP was observed under aerobic, nitrate-reducing, Fe(III)-reducing, and sulfate-reducing conditions. The biotransformation of DBP in the microcosms was significantly decrease3d as the redox potential was lowered, especially under sulfate-reducing conditions. However, other factors such as nutrient depletion and buildup of toxic intermediates could have affected the biotransformation rates. The highest DBP biotransformation rate (0.57 {micro}g DBP{center_dot}g sediment{sup {minus}1}{center_dot}day{sup {minus}1}) was under sulfate-reducing conditions. Biotransformation of DBP at 10 C was significantly enhanced by the addition of 10 mM NaNO{sub 3} suggesting that both the addition of nitrate and high redox conditions favor its biotransformation in subsurface environments.

  8. High-performance liquid chromatographic separation of the biotransformation products of oxaliplatin.

    PubMed

    Luo, F R; Yen, T Y; Wyrick, S D; Chaney, S G

    1999-03-19

    A novel single reversed-phase HPLC system was developed for separating oxaliplatin and its biotransformation products formed in rat plasma. The major stable biotransformation products of oxaliplatin formed in rat plasma were identified as Pt(dach)(Cys)2, Pt(dach)(Met) and free dach. The minor biotransformation products Pt(dach)Cl2, Pt(dach)(GSH) and Pt(dach)(GSH)2 could also be resolved from other Pt-dach complexes. Among these biotransformation products, the identification of Pt(dach)(Met) was further confirmed by LC-ESI-MS, and the identification of Pt(dach)(Cys)2, Pt(dach)(GSH), Pt(dach)(GSH)2 and free dach was confirmed by atomic absorption and double isotope labeling. This HPLC technique should prove useful for separating and identifying the biotransformation products of Pt-dach drugs such as oxaliplatin, ormaplatin and Pt(dach)(mal) in biological fluids. This will allow a more complete characterization of the pharmacokinetics and biotransformations of these Pt-dach drugs, which should in turn lead to a better understanding of the mechanisms leading to their toxicity and efficacy. PMID:10219677

  9. Determination of cyclophosphamide metabolites by gas chromatography and thermionic specific detection. Interindividual differences in hepatic biotransformation of cyclophosphamide in man in vitro.

    PubMed

    Sessink, P J; Vaes, W H; van den Broek, P H; Noordhoek, J; Bos, R P

    1995-11-17

    Sensitive methods for the determination of the cyclophosphamide metabolites nornitrogen mustard, 4-ketocyclophosphamide and carboxyphosphamide are presented. After liquid-liquid extraction and derivatization, the metabolites are determined by gas chromatography and thermionic specific detection. The methods were used to study the in vitro biotransformation of cyclophosphamide with S-9 liver fractions of human donors. The results show large interindividual differences in the formation of nornitrogen mustard and carboxyphosphamide. 4-Ketocyclophosphamide was not detected.

  10. System analysis of a piston steam engine employing the uniflow principle, a study in optimized performance

    NASA Technical Reports Server (NTRS)

    Peoples, J. A.

    1975-01-01

    Results are reported which were obtained from a mathematical model of a generalized piston steam engine configuration employing the uniflow principal. The model accounted for the effects of clearance volume, compression work, and release volume. A simple solution is presented which characterizes optimum performance of the steam engine, based on miles per gallon. Development of the mathematical model is presented. The relationship between efficiency and miles per gallon is developed. An approach to steam car analysis and design is presented which has purpose rather than lucky hopefulness. A practical engine design is proposed which correlates to the definition of the type engine used. This engine integrates several system components into the engine structure. All conclusions relate to the classical Rankine Cycle.

  11. Biotransformation of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) by denitrifying Pseudomonas sp. strain FA1.

    PubMed

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

    2003-09-01

    The microbial and enzymatic degradation of a new energetic compound, 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20), is not well understood. Fundamental knowledge about the mechanism of microbial degradation of CL-20 is essential to allow the prediction of its fate in the environment. In the present study, a CL-20-degrading denitrifying strain capable of utilizing CL-20 as the sole nitrogen source, Pseudomonas sp. strain FA1, was isolated from a garden soil. Studies with intact cells showed that aerobic conditions were required for bacterial growth and that anaerobic conditions enhanced CL-20 biotransformation. An enzyme(s) involved in the initial biotransformation of CL-20 was shown to be membrane associated and NADH dependent, and its expression was up-regulated about 2.2-fold in CL-20-induced cells. The rates of CL-20 biotransformation by the resting cells and the membrane-enzyme preparation were 3.2 +/- 0.1 nmol h(-1) mg of cell biomass(-1) and 11.5 +/- 0.4 nmol h(-1) mg of protein(-1), respectively, under anaerobic conditions. In the membrane-enzyme-catalyzed reactions, 2.3 nitrite ions (NO(2)(-)), 1.5 molecules of nitrous oxide (N(2)O), and 1.7 molecules of formic acid (HCOOH) were produced per reacted CL-20 molecule. The membrane-enzyme preparation reduced nitrite to nitrous oxide under anaerobic conditions. A comparative study of native enzymes, deflavoenzymes, and a reconstituted enzyme(s) and their subsequent inhibition by diphenyliodonium revealed that biotransformation of CL-20 is catalyzed by a membrane-associated flavoenzyme. The latter catalyzed an oxygen-sensitive one-electron transfer reaction that caused initial N denitration of CL-20. PMID:12957905

  12. Biotransformation of 2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-Hexaazaisowurtzitane (CL-20) by Denitrifying Pseudomonas sp. Strain FA1

    PubMed Central

    Bhushan, Bharat; Paquet, Louise; Spain, Jim C.; Hawari, Jalal

    2003-01-01

    The microbial and enzymatic degradation of a new energetic compound, 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20), is not well understood. Fundamental knowledge about the mechanism of microbial degradation of CL-20 is essential to allow the prediction of its fate in the environment. In the present study, a CL-20-degrading denitrifying strain capable of utilizing CL-20 as the sole nitrogen source, Pseudomonas sp. strain FA1, was isolated from a garden soil. Studies with intact cells showed that aerobic conditions were required for bacterial growth and that anaerobic conditions enhanced CL-20 biotransformation. An enzyme(s) involved in the initial biotransformation of CL-20 was shown to be membrane associated and NADH dependent, and its expression was up-regulated about 2.2-fold in CL-20-induced cells. The rates of CL-20 biotransformation by the resting cells and the membrane-enzyme preparation were 3.2 ± 0.1 nmol h−1 mg of cell biomass−1 and 11.5 ± 0.4 nmol h−1 mg of protein−1, respectively, under anaerobic conditions. In the membrane-enzyme-catalyzed reactions, 2.3 nitrite ions (NO2−), 1.5 molecules of nitrous oxide (N2O), and 1.7 molecules of formic acid (HCOOH) were produced per reacted CL-20 molecule. The membrane-enzyme preparation reduced nitrite to nitrous oxide under anaerobic conditions. A comparative study of native enzymes, deflavoenzymes, and a reconstituted enzyme(s) and their subsequent inhibition by diphenyliodonium revealed that biotransformation of CL-20 is catalyzed by a membrane-associated flavoenzyme. The latter catalyzed an oxygen-sensitive one-electron transfer reaction that caused initial N denitration of CL-20. PMID:12957905

  13. Study of bioaccumulation and biotransformation by microanalytical X-ray techniques: investigation of distribution and speciation of Cu and Cr in the body of the plant-feeding nematode, Xiphinema vuittenezi

    NASA Astrophysics Data System (ADS)

    Sávoly, Zoltán; Záray, Gyula

    2014-11-01

    Free-living nematodes, due to their microscopic size and quite complex life processes can be widely applied as biological model organisms to study the effect of soil pollutants. The modern X-ray spectrometric methods enable the individual analysis of microscopic biological samples, hereby expanding the scope of environmental and toxicological sciences. In order to study the uptake and bioaccumulation of Cu and Cr by nematodes (Xiphinema vuittenezi), the worms were starved in tap water for five days, and then treated with solutions of CuSO4, Cu(NO3)2, KCr(SO4)2 or K2CrO4 for 1-120 h. The effect of two soil-polluting elements, Cu, which is often applied in herbicides, and Cr, which is essential in the form of Cr(III), but toxic if it occurs as Cr(VI), on soil-inhabiting nematodes was studied. The uptake of these toxicants and their bioaccumulation was investigated by TXRF, following a two-step sample digestion method (digestion with HNO3 and using cold O plasma). Their effect on the essential element content of nematodes was also studied. Differences were found between the uptake of Cr(III) and Cr(VI). The Cr(III) causes decreased Zn content comparing with untreated nematodes, for Cr(VI) it was not observed. Elemental maps in the cross-sections of the worms prepared by focused gallium ion beam, following a special sample preparation method (quick-freezing in liquid nitrogen for 2 min and lyophilization for 72 h) were collected by scanning electron microscope equipped with energy dispersive X-ray detector. The distribution of Cr-P and Cu-P showed a similar pattern, however, the distribution of S deviated from these ones. According to these findings, the role of P-containing ligands in the binding of Cu and Cr is more characteristic than of S-containing ones. With the purpose of studying the speciation of the Cu and Cr in the worm, X-ray absorption near edge structure spectrometry was applied. The sample preparation method was the same as in the case of the elemental

  14. Inhibition of pyrene biotransformation by piperonyl butoxide and identification of two pyrene derivatives in Lumbriculus variegatus (Oligochaeta).

    PubMed

    Carrasco Navarro, Víctor; Brozinski, Jenny-Maria; Leppänen, Matti T; Honkanen, Jani O; Kronberg, Leif; Kukkonen, Jussi V K

    2011-05-01

    Using the freshwater annelid Lumbriculus variegatus (Oligochaeta), the presence of cytochrome P450 (CYP) isozymes was investigated by analyzing metabolites of the polycyclic aromatic hydrocarbon (PAH) pyrene in treatments with and without the CYP inhibitor piperonyl butoxide (PBO). The results show a low biotransformation capability of L. variegatus (7% of total pyrene body burden as metabolites at 168 h). Addition of PBO resulted in a significant reduction of metabolites, suggesting the presence of a CYP in L. variegatus. Besides 1-hydroxypyrene, three peaks representing unknown metabolites were detected in LC-FLD (liquid chromatography with fluorescence detection) chromatograms of L. variegatus. Deconjugations showed that sulfonation and glucosidation are involved in the formation of these unknowns. Further studies with the time of flight mass analyzer provided the identification of the glucose-sulfate conjugate of 1-hydroxypyrene. The same metabolites were detected in the solvent-nonextractable fraction by incubation of the tissue residues with proteinase K, suggesting that part of these metabolites are bound to proteins. Overall, the slow biotransformation of pyrene by L. variegatus (involving CYP) supports the use of this species in standard bioaccumulation tests; however, the tissue-bound metabolite fraction described in the current study deserves further investigation for its toxicity and availability to upper trophic levels through diet. PMID:21312247

  15. Biotransformation of Cholesterol and 16α,17α-Epoxypregnenolone and Isolation of Hydroxylase in Burkholderia cepacia SE-1

    PubMed Central

    Zhu, XiangDong; Pang, CuiPing; Cao, Yuting; Fan, Dan

    2016-01-01

    The metabolism of cholesterol is critical in eukaryotes as a precursor for vitamins, steroid hormones, and bile acids. Some steroid compounds can be transformed into precursors of steroid medicine by some microorganisms. In this study, the biotransformation products of cholesterol and 16α,17α-epoxypregnenolone produced by Burkholderia cepacia SE-1 were investigated, and a correlative enzyme, hydroxylase, was also studied. The biotransformation products, 7β-hydroxycholesterol, 7-oxocholesterol, and 20-droxyl-16α,17α-epoxypregn-1,4-dien-3-one, were purified by silica gel and Sephadex LH-20 column chromatography and identified by nuclear magnetic resonance and mass spectroscopy. The hydroxylase was isolated from the bacterium and the partial sequences of the hydroxylase, which belong to the catalases/peroxidase family, were analyzed using MS/MS analyses. The enzyme showed activity toward cholesterol and had a specific activity of 37.2 U/mg of protein at 30°C and pH 7.0. PMID:27340662

  16. Immunoproteomic identification of biotransformed self-proteins from the livers of female Balb/c mice following chronic ethanol administration.

    PubMed

    Kaur, Inderjeet; Katyal, Anju

    2012-06-01

    Chronic alcohol consumption culminates in alcoholic hepatitis which is characterized by ballooning degeneration of hepatocytes and perivenous inflammation. The aldehydes produced by ethanol oxidation and lipid peroxidation form adducts with the hepatic proteins rendering them immunogenic and initiating an autoimmune response. The present study was designed to identify these immunoreactive hepatic proteins in ethanol-treated Balb/c mice. Liver cytosolic, mitochondrial, and microsomal proteins from the ethanol-treated and control female Balb/c mice were size fractionated on SDS-PAGE and immunoblotted with the sera from the individual animal. The immunoreactive proteins were identified using antimouse IgG antibody and characterized by MALDI-TOF. It is the first report demonstrating that 15 hepatic proteins show immunoreactivity following alcohol administration. The identified autoreactive proteins ranged in function from metabolism to cytoskeletal support. Remarkably, three key enzymes of ethanol metabolism, namely alcohol dehydrogenase, aldehyde dehydrogenase I and III as well as important antioxidant enzyme glutathione S-transferase were found to be autoreactive upon ethanol treatment. We conclude that ethanol treatment induces biotransformation of host proteins from almost every compartment of the cell, especially the enzymes involved in the detoxification of ethanolic insult being the major target for biotransformation. Hence, we propose that these proteins can be the potential candidates for the biomarker studies.

  17. Effect of nitrates on biotransformation of phosphogypsum and phenol uptake in cultures of autochthonous sludge microflora from petroleum refining wastewaters.

    PubMed

    Kowalski, Włodzimierz; Przytocka-Jusiak, Magdalena; Błaszczyk, Mieczysław; Hołub, Wojciech; Wolicka, Dorota; Wesołowska, Iwona

    2002-01-01

    The effect of nitrates on the biotransformation of phosphogypsum at 30 degrees C in stationary cultures of anaerobic, heterogeneous microflora growing in medium with phenol (250-1,000 mg/L) as sole carbon source was studied. The microorganisms used in this study were isolated from sludge in biological petroleum-refining wastewater treatment plant. Phosphogypsum (a waste product in the chemical industry that contains approximately 95% CaSO4) was added in amount of 5 g/L, the source of nitrates was KNO3 in concentration equivalent to that of phenol (250-1,000 mg N-NO3/L). The presence of nitrates in heterogeneous cultures has an inhibitory effect on the process of phosphogypsum biotransformation and stimulates the uptake of phenol. We have found that in cultures in medium containing phenol, phosphogypsum and nitrates at least three physiological groups of microorganisms were present. These were phenol-biodegrading microorganisms not requiring an external electron acceptor, sulfate-reducing bacteria biodegrading phenol or intermediate products of its breakdown and denitrifying bacteria not utilising phenol as a carbon source. On solid medium these bacteria together formed heterogeneous single colonies. In spite of repeated attempts we were unable to isolate pure strains and the only result of these measures was loss of denitrification ability in medium with phenol.

  18. Biotransformation and detoxification of inorganic arsenic in a marine juvenile fish Terapon jarbua after waterborne and dietborne exposure.

    PubMed

    Zhang, Wei; Huang, Liangmin; Wang, Wen-Xiong

    2012-06-30

    Arsenic (As) is a major hazardous metalloid in many aquatic environments. This study quantified the biotransformation of two inorganic As species [As(III) and As(V)] in a marine juvenile grunt Terapon jarbua following waterborne and dietborne exposures for 10d. The fish were fed As contaminated artificial diets at nominal concentrations of 50, 150, and 500μg As(III) and As(V)/g (dry weight), and their transformation and growth responses were compared to those exposed to 100μg/L waterborne As(III) and As(V). Within the 10d exposure period, waterborne and dietborne inorganic As exposure had no significant effect on the fish growth performance. The bioaccumulation of As was very low and not proportional to the inorganic As exposure concentration. We demonstrated that both inorganic As(III) and As(V) in the dietborne and waterborne phases were rapidly biotransformed to the less toxic arsenobetaine (AsB, 89-97%). After exposure to inorganic As, T. jarbua developed correspondingly detoxified strategies, such as the reduction of As(V) to As(III) followed by methylation to less toxic organic forms, as well as the synthesis of metal-binding proteins such as metallothionein-like proteins. This study elucidated that As(III) and As(V) had little potential toxicity on marine fish.

  19. Employment type, workplace interpersonal conflict, and insomnia: a cross-sectional study of 37,646 employees in Japan.

    PubMed

    Sakurai, Kenji; Nakata, Aknori; Ikeda, Tomoko; Otsuka, Yasumasa; Kawahito, Junko

    2014-01-01

    This study explored whether workplace interpersonal conflict (WIC) is associated with insomnia, and whether the relationship between WIC and insomnia differs across different employment groups. A total of 37,646 Japanese full-time employees participated in a cross-sectional survey. Employment types included permanent employment and 2 forms of temporary employment: direct-hire and temporary work agent (TWA). Insomnia symptoms, including difficulty initiating sleep, difficulty maintaining sleep, and early morning awakening were measured. Insomnia was defined as having experienced 1 or more of these symptoms on ≥3 nights per week over the past 12 months. Results showed that WIC was significantly associated with an increased risk of insomnia (odds ratio OR = 1.63; 95% confidence interval CI = 1.55-1.71), controlling for confounders. However, the relationship between WIC and the risk of insomnia was significantly stronger for TWAs than for permanent employees (OR = 1.97; 95% CI = 1.13-3.45). A frequent exposure to WIC may increase the risk of insomnia, particularly for TWAs.

  20. Employment Type, Workplace Interpersonal Conflict, and Insomnia: A Cross-sectional Study of 37,646 Employees in Japan

    PubMed Central

    Sakurai, Kenji; Nakata, Aknori; Ikeda, Tomoko; Otsuka, Yasumasa; Kawahito, Junko

    2015-01-01

    This study explored whether workplace interpersonal conflict (WIC) is associated with insomnia, and whether the relationship between WIC and insomnia differs across different employment groups. A total of 37,646 Japanese full-time employees participated in a cross-sectional survey. Employment types included permanent employment and 2 forms of temporary employment: direct-hire and temporary work agent (TWA). Insomnia symptoms, including difficulty initiating sleep, difficulty maintaining sleep, and early morning awakening were measured. Insomnia was defined as having experienced 1 or more of these symptoms on ≥3 nights per week over the past 12 months. Results showed that WIC was significantly associated with an increased risk of insomnia (odds ratio OR = 1.63; 95% confidence interval CI = 1.55–1.71), controlling for confounders. However, the relationship between WIC and the risk of insomnia was significantly stronger for TWAs than for permanent employees (OR = 1.97; 95% CI = 1.13–3.45). A frequent exposure to WIC may increase the risk of insomnia, particularly for TWAs. PMID:23930793

  1. Biotransformation of perfumery terpenoids, (−)-ambrox® by a fungal culture Macrophomina phaseolina and a plant cell suspension culture of Peganum harmala

    PubMed Central

    2012-01-01

    Background Biotransformation offers chemo enzymatic system to modify the compounds into their novel analogues which are difficult to synthesize by chemical methods. This paper describes the biotransformational studies of ambrox, one of the most important components of natural Ambergris (wale sperm) with fungal and plant cell culture. Results Biotransformation of (−)-ambrox (1) with a fungal cell culture of Macrophomina phaseolina and a plant cell suspension cultures of Peganum harmala yielded oxygenated products, 3β-hydroxyambrox (2), 6β-hydroxyambrox (3), 1α-hydroxy-3oxoambrox (4), 1α,3β-dihydroxyambrox (5), 13,14,15,16-tetranorlabdane-3-oxo-8,12-diol (6), 3-oxoambrox (7), 2α-hydroxyambrox (8), 3β-hydroxysclareolide (9), and 2α,3β-dihydroxyambrox (10). Metabolite 4 was found to be new compound. These metabolites were structurally characterized on the basis of spectroscopic studies. Conclusion Nine oxygenated metabolites of (−)-ambrox (1) were obtained from Macrophomina phaseolina and Peganum harmala. Enzymatic system of screened organisms introduced hydroxyl and keto functionalities at various positions of compound 1 in a stereo- and regio-controlled manner. PMID:22863186

  2. Investigation of the biotransformation of melarsoprol by electrochemistry coupled to complementary LC/ESI-MS and LC/ICP-MS analysis.

    PubMed

    Baumann, Anne; Pfeifer, Thorben; Melles, Daniel; Karst, Uwe

    2013-06-01

    Melarsoprol is the only currently available drug for treatment of the late stage of African trypanosomiasis (sleeping sickness). Unfortunately, the arsenic-containing drug causes serious side effects, for which the mechanisms have not been elucidated so far. This investigation describes the study of the melarsoprol biotransformation processes by electrochemical (EC) techniques. Based on EC, potential oxidation reactions of melarsoprol are examined. Moreover, the reactivity of melarsoprol, its metabolite melarsen oxide, and their oxidation products toward the tripeptide glutathione and the proteins hemoglobin and human serum albumin is evaluated. The combination of different analytical techniques allows the identification as well as the quantification of the biotransformation products. The hyphenation of liquid chromatography (LC) and electrospray ionization mass spectrometry (ESI-MS) is applied for identification and structure elucidation, which implies the determination of exact masses and fragmentation patterns. For the selective detection of arsenic containing metabolites, LC coupled to inductively coupled plasma mass spectrometry is utilized. Based on the obtained data, the oxidative biotransformation of melarsoprol can be predicted, revealing novel species which have been suspected, but not been identified up to now. The results of the protein studies prove that melarsen oxide, the active derivative of melarsoprol, strongly binds to human hemoglobin and forms different adducts via the free cysteinyl groups of the hemoglobin α- and β-chain.

  3. Occupational Employment

    ERIC Educational Resources Information Center

    Occupational Outlook Quarterly, 2010

    2010-01-01

    When choosing a career, jobseekers often want to know which occupations offer the best prospects. Generally, occupations that have rapid job growth, many new jobs, or many job openings--and good wages--promise better opportunities. This article shows how employment in particular occupations is projected to change over the 2008-2018 decade. The…

  4. Occupational Employment

    ERIC Educational Resources Information Center

    Occupational Outlook Quarterly, 2012

    2012-01-01

    When choosing a career, jobseekers often want to know which occupations offer the best prospects. Generally, occupations that have rapid job growth, many new jobs, or many job openings--and good wages--promise better opportunities. This paper shows how employment in particular occupations is projected to change from 2010 to 2020. It presents…

  5. Animal Science Experts' Opinions on the Non-Technical Skills Secondary Agricultural Education Graduates Need for Employment in the Animal Science Industry: A Delphi Study

    ERIC Educational Resources Information Center

    Slusher, Wendy L.; Robinson, J. Shane; Edwards, M. Craig

    2010-01-01

    Non-technical, employability skills are in high demand for entry-level job-seekers. As such, this study sought to describe the perceptions of Oklahoma's animal science industry leaders as it related to the employability skills needed for entry-level employment of high school graduates who had completed coursework in Oklahoma's Agricultural, Food…

  6. Engineering of Baeyer-Villiger monooxygenase-based Escherichia coli biocatalyst for large scale biotransformation of ricinoleic acid into (Z)-11-(heptanoyloxy)undec-9-enoic acid.

    PubMed

    Seo, Joo-Hyun; Kim, Hwan-Hee; Jeon, Eun-Yeong; Song, Young-Ha; Shin, Chul-Soo; Park, Jin-Byung

    2016-06-17

    Baeyer-Villiger monooxygenases (BVMOs) are able to catalyze regiospecific Baeyer-Villiger oxygenation of a variety of cyclic and linear ketones to generate the corresponding lactones and esters, respectively. However, the enzymes are usually difficult to express in a functional form in microbial cells and are rather unstable under process conditions hindering their large-scale applications. Thereby, we investigated engineering of the BVMO from Pseudomonas putida KT2440 and the gene expression system to improve its activity and stability for large-scale biotransformation of ricinoleic acid (1) into the ester (i.e., (Z)-11-(heptanoyloxy)undec-9-enoic acid) (3), which can be hydrolyzed into 11-hydroxyundec-9-enoic acid (5) (i.e., a precursor of polyamide-11) and n-heptanoic acid (4). The polyionic tag-based fusion engineering of the BVMO and the use of a synthetic promoter for constitutive enzyme expression allowed the recombinant Escherichia coli expressing the BVMO and the secondary alcohol dehydrogenase of Micrococcus luteus to produce the ester (3) to 85 mM (26.6 g/L) within 5 h. The 5 L scale biotransformation process was then successfully scaled up to a 70 L bioreactor; 3 was produced to over 70 mM (21.9 g/L) in the culture medium 6 h after biotransformation. This study demonstrated that the BVMO-based whole-cell reactions can be applied for large-scale biotransformations.

  7. Engineering of Baeyer-Villiger monooxygenase-based Escherichia coli biocatalyst for large scale biotransformation of ricinoleic acid into (Z)-11-(heptanoyloxy)undec-9-enoic acid

    PubMed Central

    Seo, Joo-Hyun; Kim, Hwan-Hee; Jeon, Eun-Yeong; Song, Young-Ha; Shin, Chul-Soo; Park, Jin-Byung

    2016-01-01

    Baeyer-Villiger monooxygenases (BVMOs) are able to catalyze regiospecific Baeyer-Villiger oxygenation of a variety of cyclic and linear ketones to generate the corresponding lactones and esters, respectively. However, the enzymes are usually difficult to express in a functional form in microbial cells and are rather unstable under process conditions hindering their large-scale applications. Thereby, we investigated engineering of the BVMO from Pseudomonas putida KT2440 and the gene expression system to improve its activity and stability for large-scale biotransformation of ricinoleic acid (1) into the ester (i.e., (Z)-11-(heptanoyloxy)undec-9-enoic acid) (3), which can be hydrolyzed into 11-hydroxyundec-9-enoic acid (5) (i.e., a precursor of polyamide-11) and n-heptanoic acid (4). The polyionic tag-based fusion engineering of the BVMO and the use of a synthetic promoter for constitutive enzyme expression allowed the recombinant Escherichia coli expressing the BVMO and the secondary alcohol dehydrogenase of Micrococcus luteus to produce the ester (3) to 85 mM (26.6 g/L) within 5 h. The 5 L scale biotransformation process was then successfully scaled up to a 70 L bioreactor; 3 was produced to over 70 mM (21.9 g/L) in the culture medium 6 h after biotransformation. This study demonstrated that the BVMO-based whole-cell reactions can be applied for large-scale biotransformations. PMID:27311560

  8. BIOTRANSFORMATION OF TRANS-4,5-DIHYDROXY-4,5-DIHYDROBENZO[A]PYRENE TO BENZO[A]PYRENE-BIS-DIOLS AND DNA ADDUCTS BY INDUCED RAT LIVER MICROSOMES

    EPA Science Inventory

    The biotransformation of (+)-trans-4,5-dihydroxy-4,5-dihydrobenzo[a]pyrene trans-B[a]P-4,5-diol), the K-region dihydrodiol of B[a]P, by B-naphthoflavone (BNF)-induced rat liver microsomes was studied. Trans-B[a]P-4,5-diol was metabolized to six major products as characterized by...

  9. Perceptions and employment intentions among aged care nurses and nursing assistants from diverse cultural backgrounds: A qualitative interview study.

    PubMed

    Gao, Fengsong; Tilse, Cheryl; Wilson, Jill; Tuckett, Anthony; Newcombe, Peter

    2015-12-01

    The residential aged care industry faces shortages and high turnover rates of direct care workers. This situation is further complicated by the increasing cultural diversity of residents and staff. To retain direct care workers, it is crucial to explore their perceptions of the rewards and difficulties of care work, and their employment intentions in multicultural environments. A qualitative descriptive study was used to understand perceptions of the rewards and difficulties of residential aged care work for core direct care workers (i.e. nurses and nursing assistants), how these were related to their intentions to stay or leave, and how these varied between nurses and nursing assistants, and between locally and overseas born workers. Individual interviews were conducted between June and September 2013 with 16 direct care workers in an Australian residential aged care facility with a specific focus on people from culturally and linguistically diverse backgrounds. It was found that direct care workers' employment intentions were related to their perceptions and management of the rewards and difficulties of care work. Their experiences of care work, the employment characteristics, and the organizational resources that fitted their personality, ability, expectations, and essential needs were viewed as rewards. Evaluating their jobs as meaningful was a shared perception for direct care workers who intended to stay. Individual workers' perceptions of the rewarding aspects of care work served to counterbalance the challenges of care work, and promoted their intentions to stay. Perceptions and employment intentions varied by occupational groups and by cultural backgrounds. Overseas born direct care workers are valuable resources in residential aged care facility rather than a limitation, but they do require organizational support, such as cultural awareness of the management, English language support, a sense of family, and appropriate job responsibility. The findings

  10. Perceptions and employment intentions among aged care nurses and nursing assistants from diverse cultural backgrounds: A qualitative interview study.

    PubMed

    Gao, Fengsong; Tilse, Cheryl; Wilson, Jill; Tuckett, Anthony; Newcombe, Peter

    2015-12-01

    The residential aged care industry faces shortages and high turnover rates of direct care workers. This situation is further complicated by the increasing cultural diversity of residents and staff. To retain direct care workers, it is crucial to explore their perceptions of the rewards and difficulties of care work, and their employment intentions in multicultural environments. A qualitative descriptive study was used to understand perceptions of the rewards and difficulties of residential aged care work for core direct care workers (i.e. nurses and nursing assistants), how these were related to their intentions to stay or leave, and how these varied between nurses and nursing assistants, and between locally and overseas born workers. Individual interviews were conducted between June and September 2013 with 16 direct care workers in an Australian residential aged care facility with a specific focus on people from culturally and linguistically diverse backgrounds. It was found that direct care workers' employment intentions were related to their perceptions and management of the rewards and difficulties of care work. Their experiences of care work, the employment characteristics, and the organizational resources that fitted their personality, ability, expectations, and essential needs were viewed as rewards. Evaluating their jobs as meaningful was a shared perception for direct care workers who intended to stay. Individual workers' perceptions of the rewarding aspects of care work served to counterbalance the challenges of care work, and promoted their intentions to stay. Perceptions and employment intentions varied by occupational groups and by cultural backgrounds. Overseas born direct care workers are valuable resources in residential aged care facility rather than a limitation, but they do require organizational support, such as cultural awareness of the management, English language support, a sense of family, and appropriate job responsibility. The findings

  11. Process and factors influencing Italian nurse graduates' first choice of employment: a descriptive study.

    PubMed

    Palese, Alvisa; Tosatto, Donella; Mesaglio, Maura

    2009-01-01

    Describing factors influencing the first choice of employment and comparing between countries are the first step to (a) creating a global perspective, (b) encouraging reflection and awareness among staff education and developing professionals strategies, (c) reflecting on nonattractive wards or hospitals, and (d) considering the relevance of different factors emerging during international recruitment. The aim of this work is to develop the first exploratory research into which factors influence this choice for newly graduated Italian nurses, comparing with evidence from international literature. To find out which factors influence most the choice of newly graduated nurses, a questionnaire was given to new graduates who had completed the bachelor of nursing science degree course in Udine. A total of 45 nurses, with an average age of 24 years and who graduated in 2004 and had worked for 2 months, responded. To choose which hospital they would start working in, the new graduates were presented with 101 questions and had 77 interviews overall; the choice of hospital depends not only on the initial interview with the nursing directors but also on the availability of places in the requested ward. The major factors influencing the choice of the first ward are the type of patients to be nursed, the possibility to use the knowledge gained during the degree course, and the desire for professional advancement. The factors that have less influence, however, are the types of shift work and the leadership qualities of the medical director or the charge nurse. Within the limits, this first exploratory research discovers some Italian new graduates' traits in their first work experience. Taking notice of the factors involved in the choice of the first clinical placement will help the hospitals and the nursing profession to better understand the needs and expectations of the new graduates. PMID:19657250

  12. A case study of population health improvement at a Midwest regional hospital employer.

    PubMed

    Long, D Adam; Sheehan, Paula

    2010-06-01

    This article reviews the population health improvement initiative of a Midwest regional hospital employer. Services included health risk assessments, health education, and motivational health coaching conducted telephonically. Outcomes categories for this program evaluation comprised participation rates, participant satisfaction, health status and behavior change, productivity change, health care claims savings, and return on investment. Participation rates varied widely with incentive structure, although retention of participants in coaching programs averaged 89%. The participant satisfaction rate for the last 14 months of interventions was 96%. Four years of population health status and behavior trending showed significant improvements in smoking status, dietary fat and fiber intake, exercise, mental health (ie, stress, effects depressive symptoms in the past year, life satisfaction), readiness to change (ie, diet, exercise, stress, smoking, body weight), perceptions of overall health, an index of good health habits, sum of lifestyle health risks, and sum of risks and chronic conditions. Body mass index showed nonsignificant improvements during the years of greatest participation (years 2 to 4). Indicators of productivity demonstrated improvements as well. These gains were noted for employees across all health risk statuses, which suggests population health improvement strategies can influence productivity even for healthy employees. Program year 3 was evaluated for health care claims savings using a 2-stage multivariate regression approach. Stage 1 was a computation of propensity-to-participate scores. Stage 2 was an estimation of per member per month (PMPM) claims savings for participant cohorts using a propensity score-weighted linear regression analysis. Participants averaged $40.65 PMPM savings over the control population. Program return on investment, including incentive costs and vendor fees, was 2.87:1.

  13. No Significant Difference in Depression Rate in Employed and Unemployed in a Pair-Matched Study Design

    PubMed Central

    Mihai, Adriana; Ricean, Alina; Voidazan, Septimiu

    2014-01-01

    Objectives: The main objective of this study was to evaluate the differences of depression rate in employed and unemployed persons in the period of financial and economic crisis in Romania, in a pair-matched study design. Method: The cross-sectional study uses a pair match design (395 pairs) of two groups of employed and unemployed persons. Other socio-demographic risk factors of depression (gender, age, marital status, residence, ethnicity, educational level, and profession) were controlled. The study was done in a historical period of economic crisis, 2009–2010. For the screening of depression we used the patient health questionnaire-9. Results: There were no statistical differences (p = 0.054) between the depression rates in the employed (17.98%) and unemployed (23.80%) samples. The depression rate in both groups was higher in females, age (51–55), marital status (divorced), living in the rural area, with a low level of education and poverty. Suicidal ideas are more frequent in men, employed persons with low level of education and in unemployed persons with medium level of education. Conclusion: The exposure to short term unemployment status was not associated with change in depression rate in the period of financial and economic crisis in Romania, comparing with controls pair-matched. Unemployment status increases the depression rate only in vulnerable groups such as single or divorced women; and suicidal ideas were associated with the unemployment status (longer than 8 months) in men from rural area with medium level of education. PMID:25105113

  14. Bridging across OECD 308 and 309 Data in Search of a Robust Biotransformation Indicator.

    PubMed

    Honti, Mark; Hahn, Stefan; Hennecke, Dieter; Junker, Thomas; Shrestha, Prasit; Fenner, Kathrin

    2016-07-01

    The OECD guidelines 308 and 309 define simulation tests aimed at assessing biotransformation of chemicals in water-sediment systems. They should serve the estimation of persistence indicators for hazard assessment and half-lives for exposure modeling. Although dissipation half-lives of the parent compound are directly extractable from OECD 308 data, they are system-specific and mix up phase transfer with biotransformation. In contrast, aerobic biotransformation half-lives should be easier to extract from OECD 309 experiments with suspended sediments. Therefore, there is scope for OECD 309 tests with suspended sediment to serve as a proxy for degradation in the aerobic phase of the more complicated OECD 308 test, but that correspondence has remained untested so far. Our aim was to find a way to extract biotransformation rate constants that are universally valid across variants of water-sediment systems and, hence, provide a more general description of the compound's behavior in the environment. We developed a unified model that was able to simulate four experimental types (two variants of OECD 308 and two variants of OECD 309) for three compounds by using a biomass-corrected, generalized aerobic biotransformation parameter (k'bio). We used Bayesian calibration and uncertainty assessment to calibrate the models for individual experimental types separately and for combinations of experimental types. The results suggested that k'bio was a generally valid parameter for quantifying biotransformation across systems. However, its uncertainty remained significant when calibrated on individual systems alone. Using at least two different experimental types for the calibration of k'bio increased its robustness by clearly separating degradation from the phase-transfer processes taking place in the individual systems. Overall, k'bio has the potential to serve as a system-independent descriptor of aerobic biotransformation at the water-sediment interface that is equally and

  15. pH-dependent biotransformation of ionizable organic micropollutants in activated sludge.

    PubMed

    Gulde, Rebekka; Helbling, Damian E; Scheidegger, Andreas; Fenner, Kathrin

    2014-12-01

    Removal of micropollutants (MPs) during activated sludge treatment can mainly be attributed to biotransformation and sorption to sludge flocs, whereby the latter process is known to be of minor importance for polar organic micropollutants. In this work, we investigated the influence of pH on the biotransformation of MPs with cationic-neutral speciation in an activated sludge microbial community. We performed batch biotransformation, sorption control, and abiotic control experiments for 15 MPs with cationic-neutral speciation, one control MP with neutral-anionic speciation, and two neutral MPs at pHs 6, 7, and 8. Biotransformation rate constants corrected for sorption and abiotic processes were estimated from measured concentration time series with Bayesian inference. We found that biotransformation is pH-dependent and correlates qualitatively with the neutral fraction of the ionizable MPs. However, a simple speciation model based on the assumption that only the neutral species is efficiently taken up and biotransformed by the cells tends to overpredict the effect of speciation. Therefore, additional mechanisms such as uptake of the ionic species and other more complex attenutation mechanisms are discussed. Finally, we observed that the sorption coefficients derived from our control experiments were small and showed no notable pH-dependence. From this we conclude that pH-dependent removal of polar, ionizable organic MPs in activated sludge systems is less likely an effect of pH-dependent sorption but rather of pH-dependent biotransformation. The latter has the potential to cause marked differences in the removal of polar, ionizable MPs at different operational pHs during activated sludge treatment. PMID:25337862

  16. Does the choice of pre-registration paid employment impact on graduate nurse transition: an Australian study.

    PubMed

    Phillips, Craig; Kenny, Amanda; Esterman, Adrian; Smith, Colleen

    2014-04-01

    The process of transition for newly qualified registered nurses in their first year of practice remains a difficult and onerous proposition. Aside from well-documented issues pertaining to orientation, preceptorship, appropriate patient allocation, indifferent communication and feedback from senior nursing staff, other influences can determine how new graduates adjust to the role of beginning registered nurse. The dataset from a large Australian study, that examined the impact of pre-registration paid employment on graduate nurse transition, contained a significant amount of data that indicated that undergraduate work choice might influence how senior colleagues view graduate nurses during their transition to registered nurse practice. Although this issue was beyond the scope of the original study, the volume of data and recurrence of this issue provided a strong rationale for further exploration. A secondary study was designed to explore the research question does previous undergraduate work choice influence how graduate nurses are viewed by senior colleagues during their transition to registered nurse? Using secondary analysis, and an interpretive descriptive approach, two qualitative data sets arising from focus groups and open ended questionnaire responses were analysed and three organising themes identified; drawing on prior learning, the burden of employment choice and outside the setting. The global theme "confidence and perceptions" describes graduate nurses' views about their prior paid employment choice being beneficial to them and perceived to assist them in the process of transition. Findings suggest that depending on the choice of prior paid employment, new graduates (particularly those who were formerly enrolled or second level nurses) are treated differently by their senior colleagues; in terms of the level of support offered in transition, whether prior skills and experiences from previous paid employment are acknowledged, made light of or dismissed

  17. Biotransformation of the polycyclic musks HHCB and AHTN and metabolite formation by fungi occurring in freshwater environments.

    PubMed

    Martin, Claudia; Moeder, Monika; Daniel, Xavier; Krauss, Gudrun; Schlosser, Dietmar

    2007-08-01

    Micropollutants found in aquatic environments have increasingly raised concerns with respect to their uncertain environmental fate and potentially adverse effects on human health and the environment. The biodegradability of two major representatives of the polycyclic musk fragrances, Galaxolide (HHCB) and Tonalide (AHTN), and the formation of biotransformation metabolites, were investigated with Myrioconium sp. strain UHH 1-13-18-4 and Clavariopsis aquatica, two mitosporic fungi derived from freshwater environments. A particular focus was to assess the effects of extracellular oxidoreductases such as laccases, which are produced by the investigated fungi under certain conditions, on HHCB and AHTN. The fungi converted HHCB and AHTN into various products via initial hydroxylation at different carbon positions. Further metabolism resulted in the subsequent formation of diketone, peroxide, and O-methylated derivatives. Isolated laccases of the investigated fungi were able to oxidize HHCB and AHTN and catalyzed the formation of the metabolite HHCB-lactone from HHCB. At particular environmental situations also specified within the present study, biotransformations catalyzed by fungi occurring in freshwater environments may be considered when addressing the fate of polycyclic musks in freshwater systems and potential biological effects of their degradation metabolites.

  18. Products of biotransformation of polycyclic aromatic hydrocarbons in fishes of the Athabasca/Slave river system, Canada.

    PubMed

    Ohiozebau, Ehimai; Tendler, Brett; Hill, Allison; Codling, Garry; Kelly, Erin; Giesy, John P; Jones, Paul D

    2016-04-01

    Concentrations of products of biotransformation of polycyclic aromatic hydrocarbons (PBPAH) were measured in bile of five fishes of nutritional, cultural and ecological relevance from the Athabasca/Slave river system. Samples were collected in Alberta and the Northwest Territories, Canada, during three seasons. As a measure of concentrations of PBPAHs to which fishes are exposed and to gain information on the nature and extent of potential exposures of people or piscivorous wildlife, concentrations of biotransformation products of two- and three-ringed, four-ringed and five-ringed PAHs were measured using synchronous fluorescence spectroscopy. Spatial and seasonal differences were observed with greater concentrations of PBPAHs in samples of bile of fish collected from Fort McKay as well as greater concentrations of PBPAHs in bile of fish collected during summer compared to those collected in other seasons. Overall, PBPAHs were greater in fishes of lower trophic levels and fishes more closely associated with sediments. In particular, goldeye (Hiodon alosoides), consistently contained greater concentrations of all the PBPAHs studied.

  19. Aerobic biotransformation of N-nitrosodimethylamine and N-nitrodimethylamine in methane and benzene amended soil columns.

    PubMed

    Weidhaas, Jennifer; Dupont, R Ryan

    2013-07-01

    Aerobic biotransformation of N-nitrosodimethylamine (NDMA), an emerging contaminant of concern, and its structural analog N-nitrodimethylamine (DMN), was evaluated in benzene and methane amended groundwater passed through laboratory scale soil columns. Competitive inhibition models were used to model the kinetics for NDMA and DMN cometabolism accounting for the concurrent degradation of the growth and cometabolic substrates. Transformation capacities for NDMA and DMN with benzene (13 and 23μg (mgcells)(-1)) and methane (0.14 and 8.4μg (mgcells)(-1)) grown cultures, respectively are comparable to those presented in the literature, as were first order endogenous decay rates estimated to be 2.1×10(-2)±1.7×10(-3)d(-1) and 6.5×10(-1)±7.1×10(-1)d(-1) for the methane and benzene amended cultures, respectively. These studies highlight possible attenuation mechanisms and rates for NDMA and DMN biotransformation in aerobic aquifers undergoing active remediation, natural attenuation or managed aquifer recharge with treated wastewater (i.e., reclaimed water).

  20. Cell-specific biotransformation of benzophenone-2 and bisphenol-s in zebrafish and human in vitro models used for toxicity and estrogenicity screening.

    PubMed

    Le Fol, Vincent; Aït-Aïssa, Selim; Cabaton, Nicolas; Dolo, Laurence; Grimaldi, Marina; Balaguer, Patrick; Perdu, Elisabeth; Debrauwer, Laurent; Brion, François; Zalko, Daniel

    2015-03-17

    Several human and fish bioassays have been designed to characterize the toxicity and the estrogenic activity of chemicals. However, their biotransformation capability (bioactivation/detoxification processes) is rarely reported, although this can influence the estrogenic potency of test compounds. The fate of two estrogenic chemicals, the UV filter benzophenone-2 (BP2) and the bisphenol A substitute bisphenol S (BPS) was deciphered in eight human and zebrafish in vitro cell models, encompassing hepatic and mammary cellular contexts. BP2 and BPS were metabolized into a variety of gluco- and sulfo-conjugated metabolites. Similar patterns of BP2 and BPS biotransformation were observed among zebrafish models (primary hepatocytes, ZFL and ZELH-zfER cell lines). Interestingly, metabolic patterns in zebrafish models and in the human hepatic cell line HepaRG shared many similarities, while biotransformation rates in cell lines widely used for estrogenicity testing (MELN and T47D-KBLuc) were quantitatively low and qualitatively different. This study provides new data on the comparative metabolism of BP2 and BPS in human and fish cellular models that will help characterize their metabolic capabilities, and underlines the relevance of using in vitro zebrafish-based bioassays when screening for endocrine disrupting chemicals.

  1. Biotransformation studies of cresol red by Absidia spinosa M15.

    PubMed

    Kristanti, Risky Ayu; Fikri Ahmad Zubir, Meor Mohd; Hadibarata, Tony

    2016-05-01

    Cresol Red, a commercial dye that used widely to color nylon, wool, cotton, and polyacrylonitrile-modified nylon in the massive textile manufacture is toxic recalcitrant. Absidia spinosa M15, a novel fungal strain isolated from a tropical rain forest, was found to decolorize Cresol Red 65% within 30 d under agitation condition. UV-Vis spectroscopy, TLC analysis and mass spectra of samples after decolorization process in culture medium confirmed final decolorization of Cresol Red. Two metabolites were identified in the treated medium: benzeneacetic acid (tR 9.6 min and m/z 136) and benzoic acid (tR 5.7 min and m/z 122). Laccase showed the significant activity (133.8 U/L) in biomass obtained at the end of experiment demonstrates role of the enzyme in the decolorization process. PMID:26922501

  2. Biotransformation studies of cresol red by Absidia spinosa M15.

    PubMed

    Kristanti, Risky Ayu; Fikri Ahmad Zubir, Meor Mohd; Hadibarata, Tony

    2016-05-01

    Cresol Red, a commercial dye that used widely to color nylon, wool, cotton, and polyacrylonitrile-modified nylon in the massive textile manufacture is toxic recalcitrant. Absidia spinosa M15, a novel fungal strain isolated from a tropical rain forest, was found to decolorize Cresol Red 65% within 30 d under agitation condition. UV-Vis spectroscopy, TLC analysis and mass spectra of samples after decolorization process in culture medium confirmed final decolorization of Cresol Red. Two metabolites were identified in the treated medium: benzeneacetic acid (tR 9.6 min and m/z 136) and benzoic acid (tR 5.7 min and m/z 122). Laccase showed the significant activity (133.8 U/L) in biomass obtained at the end of experiment demonstrates role of the enzyme in the decolorization process.

  3. Biotransformation of xenobiotics in the human colon and rectum and its association with colorectal cancer.

    PubMed

    Beyerle, Jolantha; Frei, Eva; Stiborova, Marie; Habermann, Nina; Ulrich, Cornelia M

    2015-05-01

    In humans, the liver is generally considered to be the major organ contributing to drug metabolism, but studies during the last years have suggested an important role of the extra-hepatic drug metabolism. The gastrointestinal tract (GI-tract) is the major path of entry for a wide variety of compounds including food, and orally administered drugs, but also compounds - with neither nutrient nor other functional value - such as carcinogens. These compounds are metabolized by a large number of enzymes, including the cytochrome P450 (CYP), the glutathione S-transferase (GST) family, the uridine 5'-diphospho- glucuronosyltransferase (UDP-glucuronosyltransferase - UGT) superfamily, alcohol-metabolizing enzymes, sulfotransferases, etc. These enzymes can either inactivate carcinogens or, in some cases, generate reactive species with higher reactivity compared to the original compound. Most data in this field of research originate from animal or in vitro studies, wherein human studies are limited. Here, we review the human studies, in particular the studies on the phenotypic expression of these enzymes in the colon and rectum to get an impression of the actual enzyme levels in this primary organ of exposure. The aim of this review is to give a summary of currently available data on the relation between the CYP, the GST and the UGT biotransformation system and colorectal cancer obtained from clinical and epidemiological studies in humans. PMID:25686853

  4. A study of activities of daily living and employment in adults with autism spectrum disorders in Taiwan.

    PubMed

    Lin, Ling-Yi; Yu, Shu-Ning; Yu, Ya-Tsu

    2012-06-01

    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 range, 18-48 years; mean age, 22.8 years) with ASD in southern Taiwan. Most (85.2%) participants with ASD were men, and all lived with their caregivers or guardians. Primary caregivers or guardians completed a self-administered, written questionnaire. More than three-quarters (80.2%) of the participants with ASD could independently take care of themselves. Instrumental activities of daily living they most frequently engaged in included walking outside for more than 15 min (88.9%), light housework (85.2%), and local shopping (80.2%). Only 11 (13.6%) of the participants with ASD were employed [five (6.2%) worked more than 20 h/week] and four (4.9%) were attending school. Types of occupation consisted of serving food and beverages, baking, and cleaning. Most (81.5%) of the participants with ASD were unemployed, stayed at home, and were cared for by family members. The results of this study provide information to support the design of adequate interventions to meet the needs of adults with ASD, particularly those in Taiwan. It is important to develop adequate interventions to facilitate the functional independence of this population. Future research using larger study populations with a comparison group is needed.

  5. Two-dimensional temperature distribution measurement of flames by absorption CT employing CO{sub 2} (Experimental study on the wave number employed and the accuracy of measurement)

    SciTech Connect

    Wakai, Kazunori; Moroto, Masakazu; Takahashi, Shuhei; Bhattacharjee, S.

    1999-07-01

    The authors have developed the algorithm of infrared two-band absorption CT (computed tomography) not only for short optical path where Lambert-Beer law is applicable but also for long optical path where some band model should be applied. The authors have also shown employing CO{sub 2} as an absorption medium, statistical model as a band model and Curtis-Godson model to treat non-uniform temperature fields that when optical path is long and spectrum has steep change, there are suitable wavelengths and widths to keep good accuracy. However, it was done only by computer simulation, and in this report, those results are discussed experimentally. The flat burner was used to compare temperature measured by above method with the temperature measured by sodium D-line reversal method. The results showed good correspondence and it means that the predicted suitable wavelengths and widths are experimentally confirmed. The accuracy, namely, standard deviation of the temperature, at the best wavelength conditions was lower than 20K. Temperature distributions around non-uniform temperature distribution on the flat disk burner and domestic boiler were also measured as applications and the results show that this method is applicable for the measurement of rather complicated two-dimensional temperature distributions.

  6. Aerobic biotransformation of polybrominated diphenyl ethers (PBDEs) by bacterial isolates.

    PubMed

    Robrock, Kristin R; Coelhan, Mehmet; Sedlak, David L; Alvarez-Cohent, Lisa

    2009-08-01

    Polybrominated diphenyl ethers (PBDEs) are flame retardants that have been used in consumer products and furniture for three decades. Currently, very little is known about their fate in the environment and specifically about their susceptibility to aerobic biotransformation. Here, we investigated the ability of the polychlorinated biphenyl (PCB) degrading bacteria Rhodococcus jostii RHA1 and Burkholderia xenovorans LB400 to transform mono- through hexa-BDEs at ppb levels. We also tested the PBDE transforming abilities of the related strain Rhodococcus sp. RR1 and the ether-degrading Pseudonocardia dioxanivorans CB1190. The two PCB-degrading strains transformed all of the mono- through penta-BDEs and strain LB400 transformed one of the hexa-BDEs. The extent of transformation was inversely proportional to the degree of bromination. Strains RR1 and CB1190 were only able to transform the less brominated mono- and di-BDE congeners. RHA1 released stoichiometric quantities of bromide while transforming mono- and tetra-BDE congeners. LB400 instead converted most of a mono-BDE to a hydroxylated mono-BDE. This is the first report of aerobic transformation of tetra-, penta,- and hexa-BDEs as well as the first report of stoichiometric release of bromide during PBDE transformation.

  7. Aerobic biotransformation of polybrominated diphenyl ethers (PBDEs) by bacterial isolates

    PubMed Central

    Robrock, Kristin R.; Coelhan, Mehmet; Sedlak, David; Alvarez-Cohen, Lisa

    2009-01-01

    Polybrominated diphenyl ethers (PBDEs) are flame retardants that have been used in consumer products and furniture for three decades. Currently, very little is known about their fate in the environment and specifically about their susceptibility to aerobic biotransformation. Here, we investigated the ability of the polychlorinated biphenyl (PCB) degrading bacteria Rhodococcus jostii RHA1 and Burkholderia xenovorans LB400 to transform mono- through hexa-BDEs at ppb levels. We also tested the PBDE transforming abilities of related strain Rhodococcus sp. RR1 and the ether-degrading Pseudonocardia dioxanivorans CB1190. The two PCB-degrading strains transformed all of the mono- through penta-BDEs and strain LB400 transformed one of the hexa-BDEs. The extent of transformation was inversely proportional to the degree of bromination. Strains RR1 and CB1190 were only able to transform the less brominated mono- and di- BDE congeners. RHA1 released stoichiometric quantities of bromide while transforming mono- and tetra-BDE congeners. LB400 instead converted most of a mono-BDE to a hydroxylated mono-BDE. This is the first report of aerobic transformation of tetra-, penta- and hexa-BDEs as well as the first report of stoichiometric release of bromide during PBDE transformation. PMID:19731666

  8. Microbial biotransformation of DON: molecular basis for reduced toxicity

    NASA Astrophysics Data System (ADS)

    Pierron, Alix; Mimoun, Sabria; Murate, Leticia S.; Loiseau, Nicolas; Lippi, Yannick; Bracarense, Ana-Paula F. L.; Schatzmayr, Gerd; He, Jian Wei; Zhou, Ting; Moll, Wulf-Dieter; Oswald, Isabelle P.

    2016-07-01

    Bacteria are able to de-epoxidize or epimerize deoxynivalenol (DON), a mycotoxin, to deepoxy-deoxynivalenol (deepoxy-DON or DOM-1) or 3-epi-deoxynivalenol (3-epi-DON), respectively. Using different approaches, the intestinal toxicity of 3 molecules was compared and the molecular basis for the reduced toxicity investigated. In human intestinal epithelial cells, deepoxy-DON and 3-epi-DON were not cytotoxic, did not change the oxygen consumption or impair the barrier function. In intestinal explants, exposure for 4 hours to 10 μM DON induced intestinal lesions not seen in explants treated with deepoxy-DON and 3-epi-DON. A pan-genomic transcriptomic analysis was performed on intestinal explants. 747 probes, representing 323 genes, were differentially expressed, between DON-treated and control explants. By contrast, no differentially expressed genes were observed between control, deepoxy-DON and 3-epi-DON treated explants. Both DON and its biotransformation products were able to fit into the pockets of the A-site of the ribosome peptidyl transferase center. DON forms three hydrogen bonds with the A site and activates MAPKinases (mitogen-activated protein kinases). By contrast deepoxy-DON and 3-epi-DON only form two hydrogen bonds and do not activate MAPKinases. Our data demonstrate that bacterial de-epoxidation or epimerization of DON altered their interaction with the ribosome, leading to an absence of MAPKinase activation and a reduced toxicity.

  9. Microbial biotransformation of DON: molecular basis for reduced toxicity

    PubMed Central

    Pierron, Alix; Mimoun, Sabria; Murate, Leticia S.; Loiseau, Nicolas; Lippi, Yannick; Bracarense, Ana-Paula F. L.; Schatzmayr, Gerd; He, Jian Wei; Zhou, Ting; Moll, Wulf-Dieter; Oswald, Isabelle P.

    2016-01-01

    Bacteria are able to de-epoxidize or epimerize deoxynivalenol (DON), a mycotoxin, to deepoxy-deoxynivalenol (deepoxy-DON or DOM-1) or 3-epi-deoxynivalenol (3-epi-DON), respectively. Using different approaches, the intestinal toxicity of 3 molecules was compared and the molecular basis for the reduced toxicity investigated. In human intestinal epithelial cells, deepoxy-DON and 3-epi-DON were not cytotoxic, did not change the oxygen consumption or impair the barrier function. In intestinal explants, exposure for 4 hours to 10 μM DON induced intestinal lesions not seen in explants treated with deepoxy-DON and 3-epi-DON. A pan-genomic transcriptomic analysis was performed on intestinal explants. 747 probes, representing 323 genes, were differentially expressed, between DON-treated and control explants. By contrast, no differentially expressed genes were observed between control, deepoxy-DON and 3-epi-DON treated explants. Both DON and its biotransformation products were able to fit into the pockets of the A-site of the ribosome peptidyl transferase center. DON forms three hydrogen bonds with the A site and activates MAPKinases (mitogen-activated protein kinases). By contrast deepoxy-DON and 3-epi-DON only form two hydrogen bonds and do not activate MAPKinases. Our data demonstrate that bacterial de-epoxidation or epimerization of DON altered their interaction with the ribosome, leading to an absence of MAPKinase activation and a reduced toxicity. PMID:27381510

  10. Morbidity study of oil shale workers employed at anvil points, colorado, during 1948-1969

    SciTech Connect

    Costello, J.; Attfield, M.; Burkart, J.A.; Turner, E.R.; Krueger, G.G.

    1981-01-05

    With the advent of oil shortages caused by the oil cartel in the Middle East, the possibility of using synthetic fuels became of interest. Because of the vast reserves of shale oil on the Colorado Plateau, research on this fuel began to increase. The present morbidity study, an outgrowth and continuation of an earlier Birmingham study, was one of the results of increased interest in synthetic fuels.

  11. Study on the stability of the DNA hairpin d(ATCCAT-GTTA-TAGGAT) employing molecular dynamics simulation

    NASA Astrophysics Data System (ADS)

    Wu, Sangwook

    2015-03-01

    DNA hairpin plays a critical role in the regulation of gene expression and DNA recombination. We studied the conformation of the DNA hairpin, d(ATCCAT-GTTA-TAGGAT) (PDB id:1AC7), employing molecular dynamics (MD) simulation. Despite the non-canonical Watson-Crick base pair (G:A) in the tetraloop (GTTA), MD simulation reveals that the conformation of the DNA hairpin is remarkably stable. In this study, we discuss about the physical/chemical origin of the stability of the DNA hairpin. Department of Biomedical Engineering, Korea University, Seoul 136-703, Korea.

  12. Biotransformation of trace organic compounds by activated sludge from a biological nutrient removal treatment system.

    PubMed

    Inyang, Mandu; Flowers, Riley; McAvoy, Drew; Dickenson, Eric

    2016-09-01

    The removal of trace organic compounds (TOrCs) and their biotransformation rates, kb (LgSS(-)(1)h(-)(1)) was investigated across different redox zones in a biological nutrient removal (BNR) system using an OECD batch test. Biodegradation kinetics of fourteen TOrCs with initial concentration of 1-36μgL(-)(1) in activated sludge were monitored over the course of 24h. Degradation kinetic behavior for the TOrCs fell into four groupings: Group 1 (atenolol) was biotransformed (0.018-0.22LgSS(-)(1)h(-)(1)) under anaerobic, anoxic, and aerobic conditions. Group 2 (meprobamate and trimethoprim) biotransformed (0.01-0.21LgSS(-)(1)h(-)(1)) under anoxic and aerobic conditions, Group 3 (DEET, gemfibrozil and triclosan) only biotransformed (0.034-0.26LgSS(-)(1)h(-)(1)) under aerobic conditions, and Group 4 (carbamazepine, primidone, sucralose and TCEP) exhibited little to no biotransformation (<0.001LgSS(-)(1)h(-)(1)) under any redox conditions. BNR treatment did not provide a barrier against Group 4 compounds. PMID:27309772

  13. Aerobic biotransformation of 3-methylindole to ring cleavage products by Cupriavidus sp. strain KK10.

    PubMed

    Fukuoka, Kimiko; Ozeki, Yasuhiro; Kanaly, Robert A

    2015-09-01

    3-Methylindole, also referred to as skatole, is a pollutant of environmental concern due to its persistence, mobility and potential health impacts. Petroleum refining, intensive livestock production and application of biosolids to agricultural lands result in releases of 3-methylindole to the environment. Even so, little is known about the aerobic biodegradation of 3-methylindole and comprehensive biotransformation pathways have not been established. Using glycerol as feedstock, the soil bacterium Cupriavidus sp. strain KK10 biodegraded 100 mg/L of 3-methylindole in 24 h. Cometabolic 3-methylindole biodegradation was confirmed by the identification of biotransformation products through liquid chromatography electrospray ionization tandem mass spectrometry analyses. In all, 14 3-methylindole biotransformation products were identified which revealed that biotransformation occurred through different pathways that included carbocyclic aromatic ring-fission of 3-methylindole to single-ring pyrrole carboxylic acids. This work provides first comprehensive evidence for the aerobic biotransformation mechanisms of 3-methylindole by a soil bacterium and expands our understanding of the biodegradative capabilities of members of the genus Cupriavidus towards heteroaromatic pollutants. PMID:26126873

  14. Determining biotransformation rates of PAH in fish using a static exposure system

    SciTech Connect

    Maagd, P.G.J. de; Sijm, D.T.H.M.; Opperhuizen, A.

    1994-12-31

    In-order to quantify the influence of biotransformation on bioconcentration, juvenile fathead minnows were exposed to aqueous solutions of PAH under static conditions. During the two days of exposure both fish and water samples were taken and analyzed to determine the change in PAH concentrations in both phases with time. A numerical mathematical model was developed to calculate uptake rate constants (k{sub 1}), physico-chemical elimination rate constants (k{sub m}) and biotransformation rate constants (k{sub 2}) from concentrations in fish and water. The model assumes that biotransformation is the only process that is responsible for loss of PAH from the fish-water system. Control experiments were performed to correct for evaporation, degradation and sorption. Of the PAH tested so far (naphthalene, anthracene, phenanthrene, fluoranthene and benzo[a]anthracene) the influence of biotransformation on bioconcentration is most significant for benzo[a]anthracene and fluoranthene. Biotransformation reduced the bioconcentration of benz[a]anthracene with about an order of magnitude.

  15. Aerobic biotransformation of 3-methylindole to ring cleavage products by Cupriavidus sp. strain KK10.

    PubMed

    Fukuoka, Kimiko; Ozeki, Yasuhiro; Kanaly, Robert A

    2015-09-01

    3-Methylindole, also referred to as skatole, is a pollutant of environmental concern due to its persistence, mobility and potential health impacts. Petroleum refining, intensive livestock production and application of biosolids to agricultural lands result in releases of 3-methylindole to the environment. Even so, little is known about the aerobic biodegradation of 3-methylindole and comprehensive biotransformation pathways have not been established. Using glycerol as feedstock, the soil bacterium Cupriavidus sp. strain KK10 biodegraded 100 mg/L of 3-methylindole in 24 h. Cometabolic 3-methylindole biodegradation was confirmed by the identification of biotransformation products through liquid chromatography electrospray ionization tandem mass spectrometry analyses. In all, 14 3-methylindole biotransformation products were identified which revealed that biotransformation occurred through different pathways that included carbocyclic aromatic ring-fission of 3-methylindole to single-ring pyrrole carboxylic acids. This work provides first comprehensive evidence for the aerobic biotransformation mechanisms of 3-methylindole by a soil bacterium and expands our understanding of the biodegradative capabilities of members of the genus Cupriavidus towards heteroaromatic pollutants.

  16. Case-control study of nasal cancer in workers employed in wood-related industries.

    PubMed

    Viren, J R; Imbus, H R

    1989-01-01

    A case-control study of nasal cancer deaths in the states of Washington, Oregon, Mississippi, and North Carolina was undertaken to determine whether there was an excess of nasal cancer deaths occurring among workers in wood-related industries. This involved analysis of 536 cases of nasal cancer deaths occurring from 1962 to 1977, compared with 1,072 deaths matched for control. The study showed no overall excess of deaths from nasal cancer in wood-related industries, including furniture manufacturing. There was a statistically significant excess of deaths from nasal cancer occurring in lumber and wood products (risk ratio = 1.95, P less than .05); however, this was largely due to excess in these industries occurring in the states, of North Carolina and Mississippi. Summarizing the available evidence of this study, there seems to be no association between nasal cancer and industry/occupation normally identified with wood dust.

  17. A Study of Labour Market Information Needs through Employers' Seeking Behaviour

    ERIC Educational Resources Information Center

    Sanchez-Cuadrado, Sonia; Morato, Jorge; Andreadakis, Yorgos; Moreiro, Jose Antonio

    2010-01-01

    Introduction: The objective of this study is understand the information needs that businesses have while seeking Library and Information Science professionals and analyse how they formulate those needs. Method: The analysis is performed by examining the professional skills and capabilities demanded in job offers published. A total of 1,020 job…

  18. Labour Market Segmentation and Women's Employment: A Case-Study from the United Kingdom.

    ERIC Educational Resources Information Center

    Craig, Christine; And Others

    1985-01-01

    A summary of evidence from a study of payment structures in six industries in three local labor markets in the United Kingdom is used to show that the conditions under which labor is made available exert an influence on wages that is relatively independent of the skill, experience, and effort of the workers concerned. (Author/CT)

  19. Inclusive College Teaching: A Study of How Four Award-Winning Faculty Employ Universal Design Instruction

    ERIC Educational Resources Information Center

    Moore, Carl S.

    2013-01-01

    Using universal design instruction (UDI) as a framework, this study explores the inclusive teaching practices of four award-winning humanities and social sciences faculty at a large urban Research I university located in the northeastern region of the United States. UDI, a framework used to assist teachers in creating proactively inclusive…

  20. Self-Esteem and Employed Workers with Developmental Disabilities: A Pilot Study.

    ERIC Educational Resources Information Center

    Young, Patricia L.; And Others

    Although work, as a source of need satisfaction and self-esteem, is extremely important in our society, it has an increased meaning for people with disabilities because it permits them (and others) to perceive themselves as normal, competent citizens. This research studies the self-esteem of employees with developmental disabilities as measured by…

  1. Relationship between University Level and Employment of Language-Learning Strategies: A Study of EAP Learners

    ERIC Educational Resources Information Center

    Ghafournia, Narjes

    2014-01-01

    This study scrutinized the relationship between utilizing language-learning strategies and university levels in reading-comprehension process of language learners in Iran. The participants comprised 406 EAP students at three university levels. The findings reflected significant differences among the students in implementing learning strategies.…

  2. Results from an Experimental Study about Reinforcements Employed in Early Training

    ERIC Educational Resources Information Center

    Aparicio, Maria Teresa Sanz

    2004-01-01

    The Down's syndrome population presents a social quotient higher than its intelligence quotient, the main characteristic of its personality and because of the pronounced hypotony suffered by them, principally in the first years of life. This report shows the results of a study carried out about differential acquisitions of two groups of trisomy-21…

  3. The Impact of Technological Change; The American Experience. Studies in Employment and Unemployment.

    ERIC Educational Resources Information Center

    Haber, William; And Others

    Technological change is a complex term involving many more factors than "changes in machinery or automation." Six changes which affect jobs and influence skills in our industrial systems that could logically be called technological change have been identified: (1) scientific management, or time and motion studies, (2) mergers and consolidations,…

  4. Effective Transitional Plan from Secondary Education to Employment for Individuals with Learning Disabilities: A Case Study

    ERIC Educational Resources Information Center

    Cheong, Loh Sau; Yahya, Sharifah Zainiyah Syed

    2013-01-01

    One of the major goals in the education and training of individuals with special needs is to prepare them for independence. However, in the Malaysian context, parents who have special adolescents are in doubt as to what would be the future of their children soon after they have finished the vocational training. This case study explores the…

  5. Assessment in Specific Programs: Employment, Program, and Course Student Portfolios in Communication Studies.

    ERIC Educational Resources Information Center

    Aitken, Joan E.

    Although portfolio evaluation is the key issue with which the Department of Communication Studies at the University of Missouri, Kansas City, currently struggles, the department has yet to develop a reliable quantitative method of assessing the portfolios. The department found itself ill-prepared to have the state immediately thrust it into new…

  6. A Study of Four Federal Graduate Fellowship Programs: Education and Employment Outcomes

    ERIC Educational Resources Information Center

    Kraus, Lewis E.; Henke, Robin R.; Nevill, Stephanie; Linnard, David; Pflueger, Jeff; Mattox, Tiffany

    2008-01-01

    The Office of Postsecondary Education (OPE) in the U.S. Department of Education (ED) sponsors four graduate fellowship programs: the Fulbright-Hays Doctoral Dissertation Research Abroad (DDRA) fellowship program, the Foreign Language and Area Studies (FLAS) fellowship program, the Graduate Assistance in Areas of National Need (GAANN) fellowship …

  7. Differential activities of fungi-derived tannases on biotransformation and substrate inhibition in green tea extract.

    PubMed

    Baik, Joo Hyun; Suh, Hyung Joo; Cho, So Young; Park, Yooheon; Choi, Hyeon-Son

    2014-11-01

    Tannases are important enzymes in the antioxidant potential of tea leaves. In this study, we evaluated the effect of two tannases (T1 and T2) on biotransformation of tea polyphenols and antioxidative activities from catechins in green tea extract (GTE). The T1 tannase-catalyzed reaction was inhibited by the addition of >2.0% GTE substrate, whereas the T2-catalyzed reaction was not inhibited, even by addition of 5.0% GTE. Furthermore, the T1 tannase-catalyzed reaction was inhibited by addition of 10 mg mL(-1) EGCG, whereas the T2 tannase-catalyzed reaction did not display any inhibitory effect. These results indicate that T2 tannase was more tolerant than T1 tannase to substrate inhibition in degallation reactions. Specifically, the substrate EGCG (90,687.1 μg mL(-1)) was transformed into gallic acid (50,242.9 μg mL(-1)) and EGC (92,598.3 μg mL(-1)) after 1-h treatment with T2 tannase (500 U g(-1)). The tannase-mediated product displayed higher in vitro radical-scavenging activity than the control. IC50 value of GTE on ABTS and DPPH radicals (46.1 μg mL(-1) and 18.4 μg mL(-1), respectively) decreased markedly after T2 tannase treatment (to 35.8 μg mL(-1) and 15.1 μg mL(-1), respectively). These results indicate that T2 tannase treatment of GTE enhanced its radical-scavenging activity, an increase that was also observed in the reaction using EGCG substrate. Taken together, our results revealed that T2 tannase is more suitable for biotransformation of catechins in GTE than T1 tannase, and T2 treatment provides an enhanced radical-scavenging effect.

  8. Enantioselective Transport and Biotransformation of Chiral Hydroxylated Metabolites of Polychlorinated Biphenyls in Whole Poplar Plants

    PubMed Central

    2015-01-01

    Hydroxylated metabolites of polychlorinated biphenyls (OH-PCBs) have been found to be ubiquitous in the environment due to the oxidative metabolism of their parent PCBs. With more polarity, OH-PCBs may be more toxic and mobile than their parent compounds. However, the behavior and fate of OH-PCBs have been neglected in the environment because they are not the original contaminants. Some of these hydroxylated metabolites are chiral, and chiral compounds can be used to probe biological metabolic processes. Therefore, chiral OH-PCBs were selected to study their uptake, translocation, transformation, and enantioselectivity in plants in this work. Poplars (Populus deltoides × nigra, DN34), a model plant with complete genomic sequence, were hydroponically exposed to 5-hydroxy-2,2′,3,4′,6-pentachlorobiphenyl (5-OH-PCB91) and 5-hydroxy-2,2′,3,5′,6-pentachlorobiphenyl (5-OH-PCB95) for 10 days. Chiral 5-OH-PCB91 and 5-OH-PCB95 were clearly shown to be sorbed, taken up, and translocated in whole poplars, and they were detected in various tissues of whole poplars. However, the enantioselectivity of poplar for 5-OH-PCB91 and 5-OH-PCB95 proved to be quite different. The second-eluting enantiomer of OH-PCB95, separated on a chiral column (Phenomenex Lux Cellulose-1), was enantioselectively removed in whole poplar. Enantiomeric fractions in the middle xylem, top bark, top xylem, and stem, reached 0.803 ± 0.022, 0.643 ± 0.110, 0.835 ± 0.087, and 0.830 ± 0.029, respectively. Therefore, 5-OH-PCB95 was significantly enantioselectively biotransformed inside poplar tissues, in contrast to nearly racemic mixtures of 5-OH-PCB95 remaining in hydroponic solutions. Unlike 5-OH-PCB95, 5-OH-PCB91 remained nearly racemic in most tissues of whole poplars during 10 day exposure, suggesting the enantiomers of 5-OH-PCB91 were equally transported and metabolized in whole poplars. This is the first evidence of enantioselectivity of chiral OH-PCBs and suggests that poplars can

  9. Toxicokinetics and biotransformation of 3-(4-methylbenzylidene)camphor in rats after oral administration

    SciTech Connect

    Voelkel, Wolfgang; Colnot, Thomas; Schauer, Ute M.D.; Broschard, Thomas H.; Dekant, Wolfgang . E-mail: dekant@toxi.uni-wuerzburg.de

    2006-10-15

    3-(4-Methylbenzylidene)camphor (4-MBC) is an UV-filter frequently used in sunscreens and cosmetics. Equivocal findings in some screening tests for hormonal activity initiated a discussion on a possible weak estrogenicity of 4-MBC. In this study, the toxicokinetics and biotransformation of 4-MBC were characterized in rats after oral administration. Male and female Sprague-Dawley rats (n = 3 per group) were administered single oral doses of 25 or 250 mg/kg bw of 4-MBC in corn oil. Metabolites formed were characterized and the kinetics of elimination for 4-MBC and its metabolites from blood and with urine were determined. Metabolites of 4-MBC were characterized by {sup 1}H NMR and LC-MS/MS as 3-(4-carboxybenzylidene)camphor and as four isomers of 3-(4-carboxybenzylidene)hydroxycamphor containing the hydroxyl group located in the camphor ring system with 3-(4-carboxybenzylidene)-6-hydroxycamphor as the major metabolite. After oral administration of 4-MBC, only very low concentrations of 4-MBC were present in blood and the peak concentrations of 3-(4-carboxybenzylidene)camphor were approximately 500-fold above those of 4-MBC; blood concentrations of 3-(4-carboxybenzylidene)-6-hydroxycamphor were below the limit of detection. Blood concentration of 4-MBC and 3-(4-carboxybenzylidene)camphor peaked within 10 h after 4-MBC administration and then decreased with half-lives of approximately 15 h. No major differences in peak blood levels between male and female rats were seen. In urine, one isomer of 3-(4-carboxybenzylidene)hydroxycamphor was the predominant metabolite [3-(4-carboxybenzylidene)-6-hydroxycamphor], the other isomers and 3-(4-carboxybenzylidene)camphor were only minor metabolites excreted with urine. However, urinary excretion of 4-MBC-metabolites represents only a minor pathway of elimination for 4-MBC, since most of the applied dose was recovered in feces as 3-(4-carboxybenzylidene)camphor and, to a smaller extent, as 3-(4-carboxybenzylidene)-6-hydroxycamphor

  10. Magnetic behaviour studies on nanocrystalline cobalt ferrite by employing the Arrott plot

    NASA Astrophysics Data System (ADS)

    Kumar, Rajnish; Kar, Manoranjan

    2016-05-01

    Vibrating Sample Magnetometer (VSM) has been used to analyze the magnetic behavior of ferrimagnetic material (CoFe2O4) synthesized by the citric acid modified sol-gel method. X-ray diffraction (XRD) pattern confirms the phase purity of the sample. Its magnetic measurement has been carried out at room temperature in the field range ±1.5T. The magnetocrystalline anisotropy and saturation magnetization of CoFe2O4 are two important parameters which need to be studied for exploring its technological applications like memory device, magnetic sensors etc. Law of Approach (LA) to saturation and the Arrott plot analysis have been carried out to obtain the saturation magnetization. The difference in the saturation magnetization obtained from the two methods gives the qualitative understanding of magnetocrystalline anisotropy and lattice strain present in the sample. The present study explores a new way of analyzing magnetic hysteresis loop of nanocrystalline cobalt ferrite.

  11. Environmental toxicants as extrinsic epigenetic factors for parkinsonism: studies employing transgenic C. elegans model.

    PubMed

    Jadiya, Pooja; Nazir, Aamir

    2012-12-01

    Various human diseases are known to occur as a result of gene-environment interactions. Amongst such diseases, neurodegenerative Parkinson's disease (PD) is a complex disorder in which genetics and exposure to toxins constitute the main determinants in the onset of the disease. Many studies have reported on a link between pesticide exposure and increased risk of PD, however the role of different classes of pesticides vis-à-vis Parkinsonism has not been well elucidated. We carried out the present study to explore the role of six groups of pesticides viz botanicals, herbicides, fungicides, organophosphates, carbamates and pyrethroids on PD and and associated neurotoxic effects. These pesticides were studied using transgenic Caenorhabditis elegans model expressing human alpha synuclein protein tagged with yellow fluorescent protein [NL5901; (Punc-54::alphasynuclein::YFP+unc-119)] in the body wall muscle. Amongst all the classes of pesticides examined, botanical rotenone showed severe effects on PD pathogenesis. It significantly increased alpha synuclein aggregation and oxidative stress. Furthermore, it reduced mitochondrial and lipid content in the worms. Pesticides from other classes were observed to exert marginal effects as compared to rotenone thus suggesting that there is a class or structure specific effect of environmental chemicals vis-à-vis Parkinsonism. Hence it may be deduced that all classes of toxicants do not induce similar effects on neurodegeneration and associated events. PMID:23244436

  12. The relationship between changes in employment status and mortality risk based on the Korea Labor and Income Panel Study (2003-2008).

    PubMed

    Kim, Ji Man; Son, Nak-Hoon; Park, Eun-Cheol; Nam, Chung Mo; Kim, Tae Hyun; Cho, Woo-Hyun

    2015-03-01

    The aim of this study was to analyze the relationship between the mortality rate and changes in employment status. This study used mortality data from the Korean Labor and Income Panel Study. To analyze the relationship between the mortality rate and changes in employment status, the population was classified into employed, unemployed, or economically inactive. Demographic and socioeconomic variables such as gender, age, educational level, annual household income, marital status, and self-rated health status were controlled. In this study, the generalized estimating equations were used to analyze the relationship between the morality rate and the changes in employment status. The mortality rate was higher (odds ratio = 4.31) among the population that experienced a change in economic status from employed to unemployed than those who maintained employment. The mortality rate for the population who became unemployed or economically inactive was higher (odds ratio = 5.05) in cases of death by disease.

  13. Effect of Supported Employment on Vocational Rehabilitation Outcomes of Transition-Age Youth with Intellectual and Developmental Disabilities: A Case Control Study

    ERIC Educational Resources Information Center

    Wehman, Paul; Chan, Fong; Ditchman, Nicole; Kang, Hyun-Ju

    2014-01-01

    The purpose of this study was to examine the effect of supported employment intervention on the employment outcomes of transition-age youth with intellectual and developmental disabilities served by the public vocational rehabilitation system using a case-control study design. Data for this study were extracted from the Rehabilitation Services…

  14. Association of biodiversity with the rates of micropollutant biotransformations among full-scale wastewater treatment plant communities.

    PubMed

    Johnson, David R; Helbling, Damian E; Lee, Tae Kwon; Park, Joonhong; Fenner, Kathrin; Kohler, Hans-Peter E; Ackermann, Martin

    2015-01-01

    Biodiversities can differ substantially among different wastewater treatment plant (WWTP) communities. Whether differences in biodiversity translate into differences in the provision of particular ecosystem services, however, is under active debate. Theoretical considerations predict that WWTP communities with more biodiversity are more likely to contain strains that have positive effects on the rates of particular ecosystem functions, thus resulting in positive associations between those two variables. However, if WWTP communities were sufficiently biodiverse to nearly saturate the set of possible positive effects, then positive associations would not occur between biodiversity and the rates of particular ecosystem functions. To test these expectations, we measured the taxonomic biodiversity, functional biodiversity, and rates of 10 different micropollutant biotransformations for 10 full-scale WWTP communities. We have demonstrated that biodiversity is positively associated with the rates of specific, but not all, micropollutant biotransformations. Thus, one cannot assume whether or how biodiversity will associate with the rate of any particular micropollutant biotransformation. We have further demonstrated that the strongest positive association is between biodiversity and the collective rate of multiple micropollutant biotransformations. Thus, more biodiversity is likely required to maximize the collective rates of multiple micropollutant biotransformations than is required to maximize the rate of any individual micropollutant biotransformation. We finally provide evidence that the positive associations are stronger for rare micropollutant biotransformations than for common micropollutant biotransformations. Together, our results are consistent with the hypothesis that differences in biodiversity can indeed translate into differences in the provision of particular ecosystem services by full-scale WWTP communities.

  15. Association of Biodiversity with the Rates of Micropollutant Biotransformations among Full-Scale Wastewater Treatment Plant Communities

    PubMed Central

    Helbling, Damian E.; Lee, Tae Kwon; Park, Joonhong; Fenner, Kathrin; Kohler, Hans-Peter E.; Ackermann, Martin

    2014-01-01

    Biodiversities can differ substantially among different wastewater treatment plant (WWTP) communities. Whether differences in biodiversity translate into differences in the provision of particular ecosystem services, however, is under active debate. Theoretical considerations predict that WWTP communities with more biodiversity are more likely to contain strains that have positive effects on the rates of particular ecosystem functions, thus resulting in positive associations between those two variables. However, if WWTP communities were sufficiently biodiverse to nearly saturate the set of possible positive effects, then positive associations would not occur between biodiversity and the rates of particular ecosystem functions. To test these expectations, we measured the taxonomic biodiversity, functional biodiversity, and rates of 10 different micropollutant biotransformations for 10 full-scale WWTP communities. We have demonstrated that biodiversity is positively associated with the rates of specific, but not all, micropollutant biotransformations. Thus, one cannot assume whether or how biodiversity will associate with the rate of any particular micropollutant biotransformation. We have further demonstrated that the strongest positive association is between biodiversity and the collective rate of multiple micropollutant biotransformations. Thus, more biodiversity is likely required to maximize the collective rates of multiple micropollutant biotransformations than is required to maximize the rate of any individual micropollutant biotransformation. We finally provide evidence that the positive associations are stronger for rare micropollutant biotransformations than for common micropollutant biotransformations. Together, our results are consistent with the hypothesis that differences in biodiversity can indeed translate into differences in the provision of particular ecosystem services by full-scale WWTP communities. PMID:25398862

  16. Receptor-Drug Interaction: Europium Employment for Studying the Biochemical Pathway of G-Protein-Coupled Receptor Activation

    PubMed Central

    Antonio, Colabufo Nicola; Grazia, Perrone Maria; Marialessandra, Contino; Francesco, Berardi; Roberto, Perrone

    2007-01-01

    In medicinal chemistry field, the biochemical pathways, involved in 7-transmembrane domains G-protein coupled receptors (GPCRs) activation, are commonly studied to establish the activity of ligands towards GPCRs. The most studied steps are the measurement of activated GTP-α subunit and stimulated intracellular cAMP. At the present, many researchers defined agonist or antagonist activity of potential GPCRs drugs employing [35S]GTPγS or [3H]cAMP as probes. Recently, the corresponding lanthanide labels Eu-GTP and Eu-cAMP as alternative to radiochemicals have been developed because they are highly sensitive, easy to automate, easily synthesized, they display a much longer shelf-life and they can be used in multilabel experiments. In the present review, the receptor-drug interaction by europium employment for studying the biochemical pathway of GPCR activation has been focused. Moreover, comparative studies between lanthanide label probes and the corresponding radiolabeled compounds have been carried out. PMID:18350113

  17. Biotransformation of N-Nitrosodimethylamine by Pseudomonas mendocina KR1▿

    PubMed Central

    Fournier, Diane; Hawari, Jalal; Streger, Sheryl H.; McClay, Kevin; Hatzinger, Paul B.

    2006-01-01

    N-Nitrosodimethylamine (NDMA) is a potent carcinogen and an emerging contaminant in groundwater and drinking water. The metabolism of NDMA in mammalian cells has been widely studied, but little information is available concerning the microbial transformation of this compound. The objective of this study was to elucidate the pathway(s) of NDMA biotransformation by Pseudomonas mendocina KR1, a strain that possesses toluene-4-monooxygenase (T4MO). P. mendocina KR1 was observed to initially oxidize NDMA to N-nitrodimethylamine (NTDMA), a novel metabolite. The use of 18O2 and H218O revealed that the oxygen added to NDMA to produce NTDMA was derived from atmospheric O2. Experiments performed with a pseudomonad expressing cloned T4MO confirmed that T4MO catalyzes this initial reaction. The NTDMA produced by P. mendocina KR1 did not accumulate, but rather it was metabolized further to produce N-nitromethylamine (88 to 94% recovery) and a trace amount of formaldehyde (HCHO). Small quantities of methanol (CH3OH) were also detected when the strain was incubated with NDMA but not during incubation with either NTDMA or HCHO. The formation of methanol is hypothesized to occur via a second, minor pathway mediated by an initial α-hydroxylation of the nitrosamine. Strain KR1 did not grow on NDMA or mineralize significant quantities of the compound to carbon dioxide, suggesting that the degradation process is cometabolic. PMID:16950909

  18. Deeper insight into the reducing biotransformation of bupropion in the human liver.

    PubMed

    Skarydova, Lucie; Tomanova, Radana; Havlikova, Lucie; Stambergova, Hana; Solich, Petr; Wsol, Vladimir

    2014-01-01

    Bupropion is widely used as an antidepressant drug and also as a smoking cessation aid. In humans, this drug is extensively metabolized to form several metabolites. Oxidised hydroxybupropion and two reduced metabolites, threohydrobupropion and erythrohydrobupropion, are major metabolites. All of these metabolites are considered to be active. Although the oxidative metabolic pathway and the central role of CYP2B6 are known, the enzymes that participate in the reduction have not been identified to date. The aim of this study was to confirm the role of human liver subcellular fractions in the metabolism of bupropion and elucidate the contribution of particular carbonyl-reducing enzymes. An HPLC method for the determination of bupropion metabolites was utilised. Bupropion is reduced to threohydrobupropion and less to erythrohydrobupropion in human liver cytosol, microsomes and also mitochondria. Surprisingly, intrinsic clearance for formation of both metabolites is the highest in mitochondrial fraction. Moreover this study provides the first direct evidence that 11β-hydroxysteroid dehydrogenase 1, AKR1C1, AKR1C2, AKR1C3 and CBR1 participate in the reducing biotransformation of bupropion in vitro. The enzyme kinetics of all of these reductases was investigated and kinetic parameters were calculated.

  19. Biotransformation and improved enzymatic extraction of chlorogenic acid from coffee pulp by filamentous fungi.

    PubMed

    Torres-Mancera, María Teresa; Baqueiro-Peña, Itzamná; Figueroa-Montero, Arturo; Rodríguez-Serrano, Gabriela; González-Zamora, Eduardo; Favela-Torres, Ernesto; Saucedo-Castañeda, Gerardo

    2013-01-01

    The highest enzymatic extraction of covalent linked chlorogenic (36.1%) and caffeic (CA) (33%) acids from coffee pulp (CP) was achieved by solid-state fermentation with a mixture of three enzymatic extracts produced by Aspergillus tamarii, Rhizomucor pusillus, and Trametes sp. Enzyme extracts were produced in a practical inexpensive way. Synergistic effects on the extraction yield were observed when more than one enzyme extract was used. In addition, biotransformation of chlorogenic acid (ChA) by Aspergillus niger C23308 was studied. Equimolar transformation of ChA into CA and quinic acids (QA) was observed during the first 36 h in submerged culture. Subsequently, after 36 h, equimolar transformation of CA into protocatechuic acid was observed; this pathway is being reported for the first time for A. niger. QA was used as a carbon source by A. niger C23308. This study presents the potential of using CP to produce enzymes and compounds such as ChA with biological activities.

  20. Comparison of Bioavailability and Biotransformation of Inorganic and Organic Arsenic to Two Marine Fish.

    PubMed

    Zhang, Wei; Wang, Wen-Xiong; Zhang, Li

    2016-03-01

    Dietary uptake could be the primary route of arsenic (As) bioaccumulation in marine fish, but the bioavailability of inorganic and organic As remains elusive. In this study, we investigated the trophic transfer and bioavailability of As in herbivorous rabbitfish Siganus fuscescens and carnivorous seabass Lateolabrax japonicus. Rabbitfish were fed with one artificial diet or three macroalgae, whereas seabass were fed with one artificial diet, one polychaete, or two bivalves for 28 days. The six spiked fresh prey diets contained different proportions of inorganic As [As(III) and As(V)] and organic As compounds [methylarsenate (MMA), dimethylarsenate (DMA), and arsenobetaine (AsB)], and the spiked artificial diet mainly contained As(III) or As(V). We demonstrated that the trophic transfer factors (TTF) of As in both fish were negatively correlated with the concentrations of inorganic As in the diets, while there was no relationship between TTF and the AsB concentrations in the diets. Positive correlation was observed between the accumulated As concentrations and the AsB concentrations in both fish, suggesting that organic As compounds (AsB) were more trophically available than inorganic As. Furthermore, the biotransformation ability of seabass was higher than that in rabbitfish, which resulted in higher As accumulation in seabass than in rabbitfish. Our study demonstrated that different prey with different inorganic/organic As proportions resulted in diverse bioaccumulation of total As in different marine fish.