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1.
Article in English | MEDLINE | ID: mdl-35027938

ABSTRACT

In recent years, mindfulness-based interventions (MBIs) are rapidly growing in the workplace. Several meta-analyses conclude that overall MBIs have a moderate effect of alleviating deficit-based experiences, such as burnout and stress, but a small to no effect of promoting asset-based experiences, such as positive affect and well-being. While workplace MBIs vary greatly in their content, format, and duration, the dominant format is still face to face in a group setting, which limits scalability. Our study introduces an emerging workplace intervention called Inner Engineering Online (IEO) and evaluates its effect on reducing stress, burnout, depression, and anxiety and increasing mindfulness and joy. Drawing on the classical yogic science, IEO is a comprehensive web-based multicomponent intervention that utilizes dialectic discourse, meditation, and yogic practices designed to improve physical, mental, and emotional health. Utilizing a randomized active control cross-over experimental design with a sample of 71 employees of an Information Technology company, we tested our hypothesis that IEO training and regular daily yogic practice are likely to lower the stress levels, prevent burnout, and alleviate anxiety and depression, while at the same time promotes positive affect for employees. The results show that IEO program significantly reduces stress only among those who adhere to recommended daily yogic practices. The study is limited by its small sample size. Future research using a large sample is recommended to reexamine the effect of IEO training on occupational health. This trial is registered with NCT04126564.

2.
Anal Chem ; 80(3): 775-82, 2008 Feb 01.
Article in English | MEDLINE | ID: mdl-18181583

ABSTRACT

Anion-exchange chromatography was utilized for speciation of arsenite (As(III)), arsenate (As(V)), dimethylarsinic acid (DMA(V)), monomethylarsonic acid (MMA(V)), monomethylarsonous acid (MMA(III)), and the new As species monomethylthioarsonic acid (MMTA), using inductively coupled plasma mass spectrometric (ICPMS) detection. MMA(III) and MMTA were identified for the first time in freeze-dried carrot samples that were collected over 25 years ago as part of a joint U.S. EPA, U.S. FDA, and USDA study on trace elements in agricultural crops. The discovery of MMA(III) and MMTA in terrestrial foods necessitated the analytical characterization of synthetic standards of both species, which were used for standard addition in carrot extracts. The negative ion mode, high-resolution electrospray mass spectrometry (HR-ESI-MS) data produced molecular ions of m/z 122.9418 and 154.9152 for MMA(III) and MMTA, respectively. However, ESI-MS was not sensitive enough to directly identify MMA(III) and MMTA in the carrot extracts. Therefore, to further substantiate the identification of MMA(III) and MMTA, two additional separations using an Ion-120 column were developed using the more sensitive ICPMS detection. The first separation used 20 mM tetramethylammonium hydroxide at pH 12.2 with MMA(III) eluting in less than 7 min. In the second separation, MMTA eluted at 11.2 min by utilizing 40 mM ammonium carbonate at pH 9.0. Oxidation of MMA(III) and MMTA to MMA(V) with hydrogen peroxide was observed for standards and carrot extracts alike. Several samples of carrots collected from local markets in 2006 were also analyzed and found to contain low levels of inorganic arsenic species.


Subject(s)
Arsenic Poisoning , Arsenicals/analysis , Daucus carota/chemistry , Environmental Pollutants/analysis , Organometallic Compounds/analysis , Arsenicals/metabolism , Environmental Pollutants/chemistry , Environmental Pollutants/metabolism , Hydrogen-Ion Concentration , Organometallic Compounds/metabolism , Plant Extracts/chemistry , Quaternary Ammonium Compounds/chemistry , Spectrometry, Mass, Electrospray Ionization/methods , Time Factors
3.
Anal Bioanal Chem ; 389(3): 715-23, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17653702

ABSTRACT

An attempt was made to study selenium (Se) and mercury (Hg) interactions in plants, specifically soybean (Glycine max), by inductively coupled plasma mass spectrometric detection. Greenhouse-cultivated plants were subjected to treatment with different regimens of Se and Hg and analyzed for their metabolized species in roots, stems, leaves, pods and beans. Most of the water-soluble Hg was found to be localized in the roots in association with Se in a high molecular weight entity, as identified by size exclusion chromatography. This entity was also extracted in protein specific isolate, but it resisted enzymatic breakdown. Complete breakdown of this high molecular weight species was accomplished by acid hydrolysis. Optimization of the conditions for acid hydrolysis is discussed. Hg and Se species found in root extract were studied by ion-pairing chromatography. In a sub-study, the Se distribution pattern was found to be unaffected by the presence of Hg, but the amount of Se assimilated was found to be higher in plants coexposed to Hg.


Subject(s)
Chromatography, High Pressure Liquid/methods , Glycine max/chemistry , Mercury/antagonists & inhibitors , Plant Roots/chemistry , Selenium/antagonists & inhibitors , Mass Spectrometry/methods , Mercury/analysis , Mercury/pharmacology , Plant Extracts/analysis , Plant Extracts/chemistry , Selenium/analysis , Selenium/pharmacology , Solubility , Water/chemistry
4.
J Agric Food Chem ; 54(9): 3440-4, 2006 May 03.
Article in English | MEDLINE | ID: mdl-16637705

ABSTRACT

The incorporation of Se to fungi has been studied, focusing on element distribution among different cellular compartments and, in particular, polysaccharide structures contained in cell walls. Se-enriched mycelia of Pleurotus ostreatus were obtained in submerged cultures. The incorporation of selenium from the growth medium to mycelia was observed with the relative distribution between cytosol plus cell membranes fraction (CCM) and cell walls fraction (CW) of about 44 and 56%, respectively. CCM fractions were analyzed by size exclusion chromatography with on-line UV (280 nm) and ICP-MS detection (80Se). The results obtained showed selenium binding to components of different molecular masses (about 24% of total selenium coeluted with the compounds of molecular mass > 10 kDa). A polysaccharide-containing fraction of mycelia was treated alternatively with Tris-HCl at pH 7.5 or with chitinase. Better solubility and increased contribution of low molecular mass compounds were observed in chitinase extracts (UV detection), confirming the degradation of polysacharides by the enzyme. The total area under the ICP-MS chromatogram of chitinase extract was 2 times higher with respect to the area for Tris-HCl extract. Furthermore, the relative contribution of selenium in the low molecular mass fraction (molecular mass < 1 kDa) in chitinase extract was 72% as compared to 45% in Tris-HCl extract (based on peak area measurements with respect to total area under the chromatogram). The results obtained suggest selenium binding to chitin-containing polysaccharide structures in fungi cell walls.


Subject(s)
Cell Membrane/chemistry , Cell Wall/chemistry , Cytosol/chemistry , Mycelium/ultrastructure , Pleurotus/chemistry , Selenium/analysis , Chromatography, Gel , Mycelium/chemistry
5.
Talanta ; 70(4): 784-90, 2006 Nov 15.
Article in English | MEDLINE | ID: mdl-18970840

ABSTRACT

In the present work, speciation of selenium in dill (Anethum graveolens L.), supplemented with sodium selenite during its growth, was performed using ion pairing reversed phase and cation exchange chromatography. Heptafluorobutyric acid (HFBA) was used as the ion-pairing agent in reversed phase chromatography. In cation exchange chromatography, two different gradient programs were employed for the identification of selenospecies using pyridinium formate as the mobile phase. Low molecular weight selenocompounds were extracted from root, stem and dill leaf with 0.1M HCl. Enzymatic digestion was used for the extraction of selenospecies related to high molecular weight compounds. The chromatograms obtained from different parts of the plant revealed major differences in the type of selenospecies as well as their concentrations. The major selenospecies found in different parts of the plant is Se-methyl-selenocysteine (MeSeCys). Another major Se species identified is Se-methyl-selenomethionine (MeSeMet), which has the highest relative concentration in the root indicating possible Se volatilization from that part of the plant. Selenomethionine (SeMet) is present in minor quantities in all parts of the plant.

6.
J Chromatogr A ; 1100(2): 153-9, 2005 Dec 30.
Article in English | MEDLINE | ID: mdl-16198358

ABSTRACT

Strong cation-exchange chromatography (SCX-HPLC) was used in conjunction with inductively coupled plasma mass spectrometry (ICP-MS) to investigate cationic selenium species present in leaf extract of wild-type Brassica juncea supplemented with selenite. Total amount of Se accumulated by the leaves was found to be 352 microg g(-1). Cation-exchange solid-phase extraction (SCX-SPE) was used to pre-concentrate the cationic species present in the leaf extract. Methylselenomethionine (MeSeMet) and dimethylselenoniumproprionate (DMSeP) were synthesized and characterized by electrospray quadrupole time-of-flight MS (ESI-QTOF-MS). Laboratory synthesized and commercially available standards were used in chromatographic studies to identify the Se species in the leaf extract through retention time comparisons and standard addition method. Major cationic selenium species identified in the present study were MeSeMet and methylselenocysteine (MeSeCys) while selenomethionine (SeMet) was found in minor quantities.


Subject(s)
Chromatography, Ion Exchange/methods , Mustard Plant/chemistry , Plant Leaves/chemistry , Selenium Compounds/analysis , Spectrometry, Mass, Electrospray Ionization/methods , Chemical Fractionation/methods , Mustard Plant/metabolism , Selenium/metabolism
7.
J Agric Food Chem ; 53(13): 5138-43, 2005 Jun 29.
Article in English | MEDLINE | ID: mdl-15969488

ABSTRACT

Huitlacoche is the ethnic name of the young fruiting bodies of Ustilago maydis, a common parasite of maize. In Mexico and other Latin American countries, this fungus has been traditionally appreciated as a local delicacy. In this work a metallomics approach was used with the determination of eight elements in huitlacoche by electrothermal atomic absorption spectrometry as one facet of this approach. The results obtained indicated relatively lower concentrations of commonly analyzed metals, as referred to the data reported for other mushroom types. This effect was ascribed to different accessibilities of elements, depending on fungus substrate (lower from plant than from soil). Subcellular fractionation was accomplished by centrifugation of cell homogenates suspended in Tris-HCl buffer. Recoveries of the fractionation procedure were in the range of 71-103%. For six elements (Cr, Cu, Fe, Mn, Ni, and Pb), the mean relative contributions in cytosol, cell walls, and mixed membrane fraction were 50.7, 48.2, and 1.1% respectively. To attain the molecular weight distribution of compounds containing target elements as an additional aspect of the metallomics approach, the fungus extract (1% sodium dodecyl sulfate in Tris-HCl, 30 mmol L(-)(1), pH 7.0) was analyzed by size exclusion chromatography with UV and ICP-MS detection. With spectrophotometric detection (280 nm), the elution of high molecular weight compounds was observed in the form of one peak (MW > 10 kDa), and several lower peaks appeared at higher retention times (MW < 10 kDa). On ICP-MS chromatograms, a coelution of (59)Co, (63)Cu, (57)Fe, (202)Hg, (60)Ni, and (80)Se with the first peak on the UV chromatogram was clearly observed, indicating that a fraction of each element incorporated with high molecular weight compounds (12.7, 19.8, 33.7, 100, 19.4, and 45.8%, respectively, based on the peak area measurements). From a comparison of (80)Se and (33)S chromatograms (for sulfur analysis, the extract was obtained in the absence of SDS), both elements coeluted with the first UV peak, but their lower molecular weight compounds were apparently different. These findings may contribute to a better understanding of the accumulation of elements in mushrooms.


Subject(s)
Trace Elements/analysis , Ustilago/chemistry , Cell Fractionation , Chromatography, Gel , Mass Spectrometry , Molecular Weight , Spectrophotometry, Atomic , Ustilago/ultrastructure
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