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Classification and evolutionary studies of particularly speciose clades pose important challenges, as phylogenetic analyses typically sample a small proportion of the existing diversity. We examine here one of the largest bee genera, the genus Megachile – the dauber and leafcutting bees . Besides presenting a phylogeny based on five nuclear genes (5480 aligned nucleotide positions), we attempt to use the phylogenetic signal of mitochondrial DNA barcodes, which are rapidly accumulating and already include a substantial proportion of the known species diversity in the genus. We used barcodes in two ways: first, to identify particularly divergent lineages and thus to guide taxon sampling in our nuclear phylogeny; second, to augment taxon sampling by combining nuclear markers (as backbone for ancient divergences) with DNA barcodes. Our results indicate that DNA barcodes bear phylogenetic signal limited to very recent divergences (3–4 my before present). Sampling within clades of very closely related species may be augmented using this technique, but our results also suggest statistically supported, but incongruent placements of some taxa. However, the addition of one single nuclear gene (LW-rhodopsin) to the DNA barcode data was enough to recover meaningful placement with high clade support values for nodes up to 15 million years old. We discuss different proposals for the generic classification of the tribe Megachilini. Finding a classification that is both in agreement with our phylogenetic hypotheses and practical in terms of diagnosability is particularly challenging as our analyses recover several well-supported clades that include morphologically heterogeneous lineages. We favour a classification that recognizes seven morphologically well-delimited genera in Megachilini : Coelioxys , Gronoceras , Heriadopsis , Matangapis , Megachile , Noteriades and Radoszkowskiana . Our results also lead to the following classification changes: the groups known as Dinavis , Neglectella , Eurymella and Phaenosarus are reestablished as valid subgenera of the genus Megachile , while the subgenus Alocanthedon is placed in synonymy with M. (Callomegachile) , the subgenera Parachalicodoma and Largella with M. (Pseudomegachile) , Anodonteutricharaea with M. (Paracella) , Platysta with M. (Eurymella) , and Grosapis and Eumegachile with M. (Megachile) (new synonymies). In addition, we use maximum likelihood reconstructions of ancestral geographic ranges to infer the origin of the tribe and reconstruct the main dispersal routes explaining the current, cosmopolitan distribution of this genus. [ABSTRACT FROM AUTHOR]

To assess the recent history of taxonomy in Canada and the impact of DNA barcoding upon the field, we performed a survey of various indicators of taxonomic research over the past 30 years and also assessed the current direct impact of funds made available for taxonomy through the DNA barcoding NSERC (Natural Sciences and Engineering Research Council of Canada) network grant. Based on results from surveys of three Canadian journals, we find that between 1980 and 2000 there was a 74% decline in the number of new species described and a 70% reduction in the number of revisionary studies published by researchers based in Canada, but there was no similar decline for non-Canadian-authored research in the same journals. Between 1991 and 2007 there was a 55% decline in the total amount of inflation-corrected funds spent upon taxonomic research by NSERC’s GSC18 (Grant Selection Committee 18); this was a result of both a decrease in the number of funded taxonomists and a decrease in mean grant size. Similarly, by 2000, the number of entomologists employed at the Canadian National Collection (CNC) had decreased to almost half their 1980 complement. There was also a significant reduction in the number of active arthropod taxonomists in universities across the country between 1989 and 1996. If these declines had continued unabated, it seems possible that taxonomy would have ceased to exist in Canada by the year 2020. While slight increases in personnel have occurred recently at the CNC, the decline in financial assistance for taxonomists has been largely reversed through funds associated with DNA barcoding. These moneys have increased the financial resources available for taxonomy overall to somewhere close to NSERC’s 1980 expenditures and have also substantially increased the number of HQP (highly qualified personnel) currently being trained in taxonomy. We conclude that the criticism “DNA barcoding has taken funds away from traditional approaches to taxonomy” is false and that, in Canada at least, the advent of DNA barcoding has reversed the dramatic decline in taxonomy. We provide recommendations on how to foster the future health of taxonomy in Canada. [ABSTRACT FROM AUTHOR]

Strong evidence exists for global declines in pollinator populations. Data on the population genetics of solitary bees, especially diet specialists, are generally lacking. We studied the population genetics of the oligolectic bee Lasioglossum oenotherae, a specialist on the pollen of evening primrose (Onagraceae), by genotyping 455 females from 15 populations across the bee's North American range at six hyper-variable microsatellite loci. We found significant levels of genetic differentiation between populations, even at small geographic scales, as well as significant patterns of isolation by distance. However, using multilocus genotype assignment tests, we detected 11 first-generation migrants indicating that L. oenotherae's sub-populations are experiencing ongoing gene flow. Southern populations of L. oenotherae were significantly more likely to deviate from Hardy–Weinberg equilibrium and from genotypic equilibrium, suggesting regional differences in gene flow and/or drift and inbreeding. Short-term Ne estimated using temporal changes in allele frequencies in several populations ranged from ∼223 to 960. We discuss our findings in terms of the conservation genetics of specialist pollinators, a group of considerable ecological importance.Heredity (2007) 99, 397–405; doi:10.1038/sj.hdy.6801013; published online 30 May 2007 [ABSTRACT FROM AUTHOR]

Strenuous physical exercise induces oxidative stress. There may be a number of sources of this oxidative stress, including mitochondrial superoxide production, ischaemia-reperfusion mechanisms and auto-oxidation of catecholamines. Severe or prolonged exercise can overwhelm antioxidant defences, which include vitamins E and C and thiol antioxidants, which are interlinked in an antioxidant network, as well as antioxidant enzymes. Evidence for oxidative stress and damage during exercise comes from direct measurement of free radicals, from measurement of damage to lipids and DNA, and from measurement of antioxidant redox status, especially glutathione. There is little evidence that antioxidant supplementation can improve performance, but a large body of work suggests that bolstering antioxidant defences may ameliorate exercise-induced damage, suggesting that the benefits of antioxidant intervention may be for the long term rather than the short term. [ABSTRACT FROM AUTHOR]

We evaluated the quality of information about taxonomic identifications in 710 papers published in seven zoological journals in 2017. We found that only 10.7% of papers cited identification methods, 29.2% made available specimen-level material for later verification, and 6.9% indicated taxon concepts applied to studied animals. Only 4.0% provided details about all three practices, while almost two-thirds provided none. Invertebrate papers were more likely than vertebrate papers to provide identification methods and deposit vouchers, but taxon concepts were rarely provided, and none of the three practices were common in any category. In short, our data suggest that most zoological research is irreplicable. To address this problem, journals should require submitted manuscripts to meet the following guidelines: (1) methods used to identify studied taxa must be stated; (2) literature supporting these identifications must be cited; (3) taxon concept(s) applied to species-level taxa must be indicated; (4) specimen-level material should be available for later examination. We argue that research which falls short of these guidelines is not replicable. We provide recommendations for how authors can better document how studied animals are identified and permit others to verify their identifications, which is necessary for transparent, replicable, and ultimately scientific zoological research. [ABSTRACT FROM AUTHOR]

Coffee (genus L.) is one of the most critical global agricultural crops. Many studies have focused on coffee plants and their associated insects. This review will summarize work specifically relating to coffee plant - pollinator interactions. We review the current status of coffee as a worldwide commodity, botanical aspects of coffee, and insects associated with coffee pollination, and we assess the current understanding of the role of different pollinator taxa in increasing fruit set and yield. [ABSTRACT FROM AUTHOR]

Hereditary hemochromatosis (HHC) is a late-onset, autosomal recessive disorder leading to a chronic iron overload syndrome, finally causing diabetes, cardiomyopathy and liver disease. HHC is the most common single gene disorder in northern Europeans that occurs with a frequency of approximately 0.5%, and most of these patients carry the C282Y and H63D mutation in the HFE gene on chromosome 6p21.3. The vast majority of HHC patients are homozygous for the C282Y mutation, but HHC phenotypes are observed in other genotypes. Expression of the disease, in those homozygous for the C282Y mutation, is highly variable depending on the various features of the population studied. C282Y heterozygotes have slightly increased iron stores and in absence of other genetic and/or environmental factors do usually not develop the HHC phenotype. It is currently a matter of debate whether C282Y heterozygotes may have an increased risk for morbidity. Different studies investigating the association of C282Y heterozygocity with morbidity have given conflicting results, as is exemplified by extrahepatic cancers, cardiovascular diseases, alcoholic liver disease, and diabetes. However, there are examples of clear and unambiguous disease associations, such as with sporadic pophyria cutanea tarda. It remains to be seen whether a strong correlation between the C282Y heterozygous state and distinct pathological conditions will exist and large-scale genotyping studies will help to identify such potential risk groups in the future. [Copyright &y& Elsevier]

Vitamin E, the most important lipid-soluble antioxidant, was discovered at the University of California at Berkeley in 1922 in the laboratory of Herbert M. Evans (Science 1922, 55: 650). At least eight vitamin E isoforms with biological activity have been isolated from plant sources. Since its discovery, mainly antioxidant and recently also cell signaling aspects of tocopherols and tocotrienols have been studied. Tocopherols and tocotrienols are part of an interlinking set of antioxidant cycles, which has been termed the antioxidant network. Although the antioxidant activity of tocotrienols is higher than that of tocopherols, tocotrienols have a lower bioavailability after oral ingestion. Tocotrienols penetrate rapidly through skin and efficiently combat oxidative stress induced by UV or ozone. Tocotrienols have beneficial effects in cardiovascular diseases both by inhibiting LDL oxidation and by down-regulating 3-hydroxyl-3-methylglutaryl-coenzyme A (HMG CoA) reductase, a key enzyme of the mevalonate pathway. Important novel antiproliferative and neuroprotective effects of tocotrienols, which may be independent of their antioxidant activity, have also been described. [ABSTRACT FROM AUTHOR]

Highlights • Shutdown dose rate benchmark experiment has been performed at JET during high performance DD campaign in preparation of DTE2. • The scope of the experiment is to validate EU D1S and R2S codes used for SDR assessment in ITER. • Dedicated calibrations and efforts are performed to reduce the uncertainties and to optimize the experimental layout for TT and DTE2 campaigns. Abstract A novel Shutdown dose rate benchmark experiment has been performed at Joint European Torus (JET) machine during the last high performance Deuterium–Deuterium (DD) campaign in preparation of future high Deuterium-Tritium experiment (DTE2). On-line continuous gamma dose rate measurements were performed for four months at two ITER relevant ex-vessel positions close to Radial Neutron Camera and on the top of ITER-like Antenna using high-sensitive ionization chambers. Decay gamma spectra at the shutdown were also collected using High Purity Germanium spectrometer to identify dominant radionuclides contributing to the dose. Neutron fluence measurements during operations were performed as well using activation foils assembly installed close to ionization chambers. The measurements are performed to validate shutdown dose rate tools used in ITER. This paper presents the experimental assembly and measurements analyses. [ABSTRACT FROM AUTHOR]

In preparation for the upcoming deuterium-tritium campaign at the JET tokamak, the ex-vessel fission chamber neutron diagnostics and the neutron activation system will be calibrated in absolute terms at 14 MeV neutron energy, to a required accuracy of less than 10%. Two nominally identical DT neutron generators were chosen as the calibration sources, both of which were fully calibrated and characterized at the UK’s National Physical Laboratory. The neutron activation method was adopted as a complementary method for the purpose of determining the absolute value of the neutron yield from the neutron generators and to provide a means of cross check for the active detection methods being employed. The work being presented here shows the derivation of the neutron emission rate from the neutron generators based upon experimental activation foil measurements. [ABSTRACT FROM AUTHOR]

The Helium Cooled Pebble Bed (HCPB) breeder blanket is being developed as part of the European Fusion Programme. Part of the programme is to investigate blanket designs relevant for future demonstration fusion power plants. This paper presents neutronics analyses of the HCPB with an alternative neutron multiplier, Be 12 Ti which is incorporated into the design, replacing the current Be multiplier. A parameter study was performed for a range of geometries to identify the optimal heights of the lithium ceramic and neutron multiplier pebble beds. Automated creation of CAD models followed by conversion to constructive solid geometry (CSG) and unstructured mesh (UM) geometry allows the models to be useful for both neutronics simulations and engineering simulations. In this neutronics study simulations were performed using MCNP 6.1 to find the tritium breeding ratio, energy multiplication and the volumetric heat loads of different blanket designs. Combinations of geometry parameters and material choices that resulted in adequate TBR values were identified and will be further investigated with automated engineering simulations. This paper provides insight, supported by neutronics analysis, on the validity of the design and comments on some of the potential advantages and disadvantages of using Be 12 Ti in the Helium Cooled Pebble Bed (HCPB) breeder blanket. Blankets with Be 12 Ti neutron multiplier were found to produce less tritium but higher energy multiplication when compared to blankets with Be neutron multiplier. [ABSTRACT FROM AUTHOR]

Neutronics benchmark experiments are conducted at JET in the frame of WPJET3 NEXP within EUROfusion Consortium for validating the neutronics codes and tools used in ITER nuclear analyses to predict quantities such as the neutron flux along streaming paths and dose rates at the shutdown due to activated components. The preparation of neutron streaming and shutdown dose rate experiments for the future Deuterium-Tritium operations (DTE2 campaign) are in progress. This paper summarizes the status of measurements and analyses in progress in the current Deuterium–Deuterium (DD) campaign and the efforts in preparation for DTE2. [ABSTRACT FROM AUTHOR]

Beryllium (Be) is a precious resource with many high value uses, the low energy threshold (n,2n) reaction makes Be an excellent neutron multiplier for use in fusion breeder blankets. Estimates of Be requirements and available resources suggest that this could represent a major supply difficulty for solid-type blanket concepts. Reducing the quantity of Be required by breeder blankets would help to alleviate the problem to some extent. In addition, it is important that the reduction in the Be quantity does not diminish the blanket's performance in key aspects such as the tritium breeding ratio (TBR), energy multiplication and peak nuclear heating. Mixed pebble bed designs allow for the multiplier fraction to be varied throughout the blanket. This neutronics study used MCNP 6 to investigate linear variations of the multiplier fraction in relation to blanket depth, in order to better utilise the important multiplying Be(n,2n) and breeding reactions. Blankets with a uniform multiplier fraction showed little scope for reduction in Be mass. Blankets with varying multiplier fractions were able to simultaneously use 10% less Be, increase the energy amplification by 1%, reduce the peak heating by 7% and maintaining a sufficient TBR when compared to the performance achievable using a uniform composition. [ABSTRACT FROM AUTHOR]

In the frame of the WPJET3-DT Technology project within the EUROfusion Consortium program, neutronics experiments are in preparation for the future deuterium–tritium campaign on JET (DTE2). The experiments will be conducted with the purpose to validate the neutronics codes and tools used in ITER, thus reducing the related uncertainties and the associated risks in the machine operation. This paper summarizes the status of previous shutdown dose rate benchmarks experiments and analyses performed at JET and focuses on the computational and experimental efforts conducted in preparation of the future DTE2 experiments. In particular, preliminary calculations and studies to select detectors and positions aimed to reduce uncertainties in the shutdown dose rate experiment are presented and discussed. [ABSTRACT FROM AUTHOR]

A dedicated effort on nuclear data validation and nuclear instrumentation techniques for Test Blanket Modules (TBM) in ITER is conducted as an integral part of Fusion for Energy's (F4E) programme to ensure validated nuclear analysis capabilities for fusion technology applications. It is closely linked to nuclear data development activities, which are jointly coordinated and conducted by F4E and nuclear data consortia formed by European research institutions. The current experimental activities, an integral copper validation experiment and gas production experiments in EUROFER elements, as well as activities on the development and testing of candidate nuclear detectors for TBM in ITER and the related design integration assessment are presented in this paper. [ABSTRACT FROM AUTHOR]

This review considers current Zr alloys and opportunities for advanced zirconium alloys to meet the demands of a structural material in fusion reactors. Zr based materials in the breeder blanket offer the potential to increase the tritium breeding ratio above that of Fe, Si and V based materials. Current commercial Zr alloys might be considered as a material in water-cooled breeder blanket designs, due to the similar operating temperature to fission power plants. For breeder blankets designed to operate at higher temperatures, current commercial Zr alloys will not meet the high temperature strength and thermal creep requirements. Hence, Zr alloys with an operational temperature capability beyond that of current commercial fission alloys have been reviewed, specifically: binary Zr alloy systems Zr-Al, Zr-Be, Zr-Cr, Zr-Nb Zr-Ti, Zr-Si, Zr-Sn, Zr-V and Zr-W; as well as higher order Zr alloys Zr-Mo-Ti, Zr-Nb-Ti, Zr-Ti-Al-V and Zr-Mo-Sn. It is concluded that, with further work, higher order Zr alloys could achieve the required high temperature strength, alongside ductility, while maintaining a low thermal neutron cross-section. However, there is limited data and uncertainty regarding the structural performance and microstructural stability of the majority of advanced Zr alloys for temperatures 500–700 °C, at which they would be expected to operate for helium- and liquid metal-cooled breeder blanket designs. [ABSTRACT FROM AUTHOR]

• First neutronics assessment of alternative divertor configurations in DEMO. • Shielding proposals to reduce TF coil heat loads and neutron streaming. • DPA, helium production and to assess material damage and lifetimes of components. • MCNP model constructed for SN, SX and XD divertor configurations. • Tritium breeding ratio (TBR) calculated for SN, SX and XD divertor configurations. As a demonstration fusion power plant, EU DEMO has to prove the maturity of fusion technology and its viability for electricity production. The central requirements for DEMO rest on its capability to generate significant net electric power to the grid (300 MW to 500 MW) safely and consistently. Plant availability and lifetime will approach that of a commercial fusion power plant. Operating at such regimes presents many complex challenges, of which one is plasma exhaust. To mitigate the risk that the implementation in preceding experimental devices, namely ITER, does not extrapolate to the requirement of DEMO, alternative solutions must be sought. The investigation of alternative divertor configurations was born out of this motive, seeking to resolve a 'critical' challenge for the realisation of DEMO. In this paper, we study the neutronics performance of three concepts: Single Null (SN), Super-X (SX) and X-divertor (XD). This is the first time a preliminary analysis of alternative configurations to the SN baseline has been performed. The shielding proposals and design recommendations presented herein should be integrated with other engineering and physics constraints in future iterations of the chosen divertor concept. [ABSTRACT FROM AUTHOR]

BACKGROUND: The racemic mixture, RS-(+/-)-alpha-lipoic acid (rac-LA) has been utilized clinically and in a variety of disease models. Rac-LA and the natural form, R-lipoic acid (RLA), are widely available as nutritional supplements, marketed as antioxidants. Rac-LA sodium salt (NaLA) or rac-LA potassium salt (KLA) has been used to improve the aqueous solubility of LA. STUDY RATIONALE: Several in vitro and animal models of aging and age-related diseases have demonstrated efficacy for the oral solutions of LA salts in normalizing age-related changes to those of young animals. Other models and studies have demonstrated the superiority of RLA, the naturally occurring isomer over rac-LA. Despite this, RLA pharmacokinetics (PK) is not fully characterized in humans, and it is unknown whether the concentrations utilized in animal models can be achieved in vivo. Due to its tendency to polymerize, RLA is relatively unstable and suffers poor aqueous solubility, leading to poor absorption and low bioavailability. A preliminary study demonstrated the stability and bioavailability were improved by converting RLA to its sodium salt (NaRLA) and pre-dissolving it in water. The current study extends earlier findings from this laboratory and presents PK data for the 600-mg oral dosing of 12 healthy adult subjects given NaRLA. In addition, the effect of three consecutive doses was tested on a single subject relative to a one-time dosing in the same subject to determine whether plasma maximum concentration (Cmax) and the area under the plasma concentration versus time curve (AUC) values were comparable to those in animal studies and those achievable via intravenous infusions in humans. METHODS: Plasma RLA was separated from protein by a modification of a published method. Standard curves were generated from spiking known concentrations of RLA dissolved in ethanol and diluted in a phosphate-buffered saline (PBS) into each individual's baseline plasma to account for inter-individual differences in protein binding and to prevent denaturing of plasma proteins. Plasma RLA content was determined by the percent recovery using high-performance liquid chromatography (electrochemical/coulometric detection) (HPLC/ECD). RESULTS: As anticipated from the preliminary study, NaRLA is less prone to polymerization, completely soluble in water, and displays significantly higher Cmax and AUC values and decreased time to maximum concentration (Tmax) and T1/2 values than RLA or rac-LA. In order to significantly extend Cmax and AUC, it is possible to administer three 600-mg RLA doses (as NaRLA) at 15-minute intervals to achieve plasma concentrations similar to those from a slow (20-minute) infusion of LA. This is the first study to report negligible unbound RLA even at the highest achievable plasma concentrations. [ABSTRACT FROM AUTHOR]

In contrast to cutaneous melanoma, there is no evidence that BRAF mutations are involved in the activation of the mitogen-activated protein kinase (MAPK) pathway in uveal melanoma, although there is increasing evidence that this pathway is activated frequently in the latter tumours. In this study, we performed mutation analysis of the RAS and BRAF genes in a panel of 11 uveal melanoma cell lines and 19 primary uveal melanoma tumours. In addition, Western blot and immunohistochemical analyses were performed on downstream members of the MAPK pathway in order to assess the contribution of each of these components. No mutations were found in any of the three RAS gene family members and only one cell line carried a BRAF mutation (V599E). Despite this, mitogen-activated protein kinase/extracellular signal-regulated kinase kinase (MEK), ERK and ELK were constitutively activated in all samples. These data suggest that activation of the MAPK pathway is commonly involved in the development of uveal melanoma, but occurs through a mechanism different to that of cutaneous melanoma.British Journal of Cancer (2005) 92, 2032-2038. doi:10.1038/sj.bjc.6602598 www.bjcancer.com [ABSTRACT FROM AUTHOR]

One promising class of antioxidant compounds is polyphenols, contained abundantly in pine bark extract(Pycnogenol®—pine bark extract). This medicinal extract is utilized for its anti-inflammatory properties. Its pharmacological action in skin depends on the kinetics of its absorption. In this study the dermal bioavailability of pine bark extract was investigated. Viable human skin, adapted on continuously perfused Franz cells, was applied with 5%(w/v) pine bark solution. Samples were taken at 0.5, 1, 2, 4, 6, 8, 10, and 12-hour intervals and analyzed for detection of pine bark extract constituents by high performance liquid chromatography(HPLC)(reversed phase column, isocratic conditions) coupled with an electrochemical detector(EC). Several constituents of pine bark extract such as gallic acid, protocatechuic acid, catechin, p-hydroxybenzoic acid, vanillin, and one unidentified constituent were detected. These findings indicate that pine bark extract is readily absorbed by human skin and can be used for topical application. [ABSTRACT FROM AUTHOR]

Exposure to ultraviolet radiation or ozone leads to skin damage including oxidation of skin biomolecules, as well as to depletion of constitutive antioxidants. The highly organized stratum corneum forming the main barrier against most xenobiotics is particularly susceptible to such damage and possible barrier perturbation may be the consequence. Whereas ample evidence exists for an increased permeability for different solutes including water after exposure to ultraviolet radiation, such an effect has not yet been reported for ozone. This study reports on the effect of such oxidative stressors using the hairless mouse as the skin model and measuring temperature-controlled transepidermal water loss (TEWL) as an indicator for skin barrier integrity. First, a strong dependency of the TEWL on skin temperature was observed, an effect that was clearly more pronounced than that found in man. Given this temperature dependency in untreated animals, we proceeded to determine the effects of both ultraviolet radiation and ozone on TEWL over a relevant physiological skin temperature range. Solar-simulated ultraviolet radiation (0.75-3 minimal erythemal dose) resulted in a delayed and dose-dependent skin barrier disruption over the entire temperature range investigated. Conversely, daily ozone exposure at 2 ppm for 1 week, however, did not significantly alter TEWL up to 72 h after the last exposure. The results demonstrate a differential response of the epidermis to two environmental stressors associated with oxidative damage; they suggest that chronic ozone exposure at relevant environmental levels does not lead to a detectable skin barrier defect, while solar UV exposure was demonstrated to increase epidermal water loss. Furthermore, experimental evidence clearly suggests that future studies applying TEWL measurements in animal models should be performed under carefully controlled skin temperature conditions. [ABSTRACT FROM AUTHOR]

Exposure to environmental tobacco smoke (ETS) has been linked to increased risk of lung cancer and cardiovascular diseases in nonsmokers. Current research suggests that some of these diseases are associated with elevated oxidative stress. We investigated the effect of antioxidant (AO) intervention on the lipid peroxidation biomarker F2-isoprostanes (F2-IsoPs), an index of oxidative stress, in plasma of nonsmokers exposed to ETS (passive smokers). We measured free F2-IsoP concentrations in plasma of 67 passive smokers at baseline and after 2 mo of daily intervention with AOs or placebo. The study subjects (47 females, 20 males; mean age 46 +/-15) were randomized into one of three treatment groups: vitamin C, 'mixture' (vitamin C, vitamin E, and a-lipoic-acid), and placebo. Investigated confounders included plasma baseline AO levels, lipid and total cholesterol profiles, transferrin saturation, and C-reactive protein. Plasma F2IsoP concentrations of subjects in the vitamin C and mixture groups decreased significantly by 17.2 pmol/l (P = 0.0105) and 19.2 pmol/l (P = 0.0083) when compared with the placebo group (11.4% and 12.7%, respectively). Daily AO supplementation (especially with vitamin C) decreases this oxidative stress biomarker in passive smokers. This finding might be of importance for the prevention of ETS-associated adverse health effects in nonsmokers. [ABSTRACT FROM AUTHOR]

Presents information on a study which described several methods to assess free radicals and oxidative stress in biological systems. Definition of free radicals; Direct detection of free radicals by electron paramagnetic resonance spectroscopy; Measurement of oxidative damage to lipids, proteins and DNA.