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Sample records for naturally occurring isotopes

  1. URBAN STORMWATER TRACING WITH THE NATURALLY OCCURRING DEUTERIUM ISOTOPE

    EPA Science Inventory

    Measurements of the naturally-occurring deuterium isotope assist the tracing of water components during wet-weather flows in an urban watershed. A transect of installations in the vadose and saturated zones was completed in the vicinity of a small stream and storm sewer. High-r...

  2. The Role of Naturally Occurring Stable Isotopes in Mass Spectrometry, Part II: The Instrumentation

    PubMed Central

    Bluck, Les; Volmer, Dietrich A.

    2013-01-01

    In the second instalment of this tutorial, the authors explain the instrumentation for measuring naturally occurring stable isotopes, specifically the magnetic sector mass spectrometer. This type of instrument remains unrivalled in its performance for isotope ratio mass spectrometry (IRMS) and the reader is reminded of its operation and its technical advantages for isotope measurements. PMID:23772101

  3. Existence of long-lived isomeric states in naturally-occurring neutron-deficient Th isotopes

    SciTech Connect

    Marinov, A.; Kashiv, Y.; Rodushkin, I.; Halicz, L.; Segal, I.; Pape, A.; Miller, H. W.; Kolb, D.; Brandt, R.

    2007-08-15

    Four long-lived neutron-deficient Th isotopes with atomic mass numbers 211 to 218 and abundances of (1-10)x10{sup -11} relative to {sup 232}Th have been found in a study of naturally-occurring Th using inductively coupled plasma-sector field mass spectrometry. It is deduced that long-lived isomeric states exist in these isotopes. The hypothesis that they might belong to a new class of long-lived high spin super- and hyperdeformed isomeric states is discussed.

  4. APPLICATION OF THE NATURALLY-OCCURRING DEUTERIUM ISOTOPE TO TRACING THE CAPILLARY FRINGE

    EPA Science Inventory

    Naturally-occurring deuterium is a useful tracer of subsurface hydrologic processes. A possible application includes the identification of capillary fringes in the vadose zone. Multiple and discontinuous water tables persist in many temperate regions, under various hydrogeologi...

  5. BIODEGRADATION - MONITORED NATURAL ATTENUATION (MNA) FOR OXYGENATES: HOW IT EVOLVED, WHY IT OCCURS AND STABLE ISOTOPES

    EPA Science Inventory

    The organisms that degrade MtBE under anaerobic conditions are evolved to acquire energy for growth by using molecular hydrogen and carbonate ion to cleave methyl ether bonds. Methyl ether bonds are common in nature and the bond also occurs in MTBE. MTBE in contaminated ground...

  6. Naturally occurring chemical carcinogens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Natural products are chemicals found in nature which have unique pharmacological effects. Humans are exposed to many of these bioactive naturally occurring chemicals via the air breathed, the water drunk and the food eaten. Exposure also occurs in clinical settings. Naturally occurring chemicals ...

  7. Compilation of minimum and maximum isotope ratios of selected elements in naturally occurring terrestrial materials and reagents

    USGS Publications Warehouse

    Coplen, T.B.; Hopple, J.A.; Bhlke, J.K.; Peiser, H.S.; Rieder, S.E.; Krouse, H.R.; Rosman, K.J.R.; Ding, T.; Vocke, R.D., Jr.; Revesz, K.M.; Lamberty, A.; Taylor, P.; De Bievre, P.

    2002-01-01

    Documented variations in the isotopic compositions of some chemical elements are responsible for expanded uncertainties in the standard atomic weights published by the Commission on Atomic Weights and Isotopic Abundances of the International Union of Pure and Applied Chemistry. This report summarizes reported variations in the isotopic compositions of 20 elements that are due to physical and chemical fractionation processes (not due to radioactive decay) and their effects on the standard atomic weight uncertainties. For 11 of those elements (hydrogen, lithium, boron, carbon, nitrogen, oxygen, silicon, sulfur, chlorine, copper, and selenium), standard atomic weight uncertainties have been assigned values that are substantially larger than analytical uncertainties because of common isotope abundance variations in materials of natural terrestrial origin. For 2 elements (chromium and thallium), recently reported isotope abundance variations potentially are large enough to result in future expansion of their atomic weight uncertainties. For 7 elements (magnesium, calcium, iron, zinc, molybdenum, palladium, and tellurium), documented isotope-abundance variations in materials of natural terrestrial origin are too small to have a significant effect on their standard atomic weight uncertainties. This compilation indicates the extent to which the atomic weight of an element in a given material may differ from the standard atomic weight of the element. For most elements given above, data are graphically illustrated by a diagram in which the materials are specified in the ordinate and the compositional ranges are plotted along the abscissa in scales of (1) atomic weight, (2) mole fraction of a selected isotope, and (3) delta value of a selected isotope ratio. There are no internationally distributed isotopic reference materials for the elements zinc, selenium, molybdenum, palladium, and tellurium. Preparation of such materials will help to make isotope ratio measurements among laboratories comparable. The minimum and maximum concentrations of a selected isotope in naturally occurring terrestrial materials for selected chemical elements reviewed in this report are given below: Isotope Minimum mole fraction Maximum mole fraction -------------------------------------------------------------------------------- 2H 0 .000 0255 0 .000 1838 7Li 0 .9227 0 .9278 11B 0 .7961 0 .8107 13C 0 .009 629 0 .011 466 15N 0 .003 462 0 .004 210 18O 0 .001 875 0 .002 218 26Mg 0 .1099 0 .1103 30Si 0 .030 816 0 .031 023 34S 0 .0398 0 .0473 37Cl 0 .240 77 0 .243 56 44Ca 0 .020 82 0 .020 92 53Cr 0 .095 01 0 .095 53 56Fe 0 .917 42 0 .917 60 65Cu 0 .3066 0 .3102 205Tl 0 .704 72 0 .705 06 The numerical values above have uncertainties that depend upon the uncertainties of the determinations of the absolute isotope-abundance variations of reference materials of the elements. Because reference materials used for absolute isotope-abundance measurements have not been included in relative isotope abundance investigations of zinc, selenium, molybdenum, palladium, and tellurium, ranges in isotopic composition are not listed for these elements, although such ranges may be measurable with state-of-the-art mass spectrometry. This report is available at the url: http://pubs.water.usgs.gov/wri014222.

  8. Radiometric method for determining concentration of naturally occurring isotopes and device therefor

    SciTech Connect

    Yakubovich, S.L.; Gerling, V.E.; Golubnichy, V.V.; Kotsen, M.E.; Stepanov, J.N.

    1984-10-09

    The proposed method essentially consists in that a sample of a substance is placed between two scintillators in immediate contact therewith whereupon said sample is hermetically sealed. Arranged in close proximity to each scintillator is a photomultiplier tube recording ionizing ..cap alpha..- and b-radiation. A selector is utilized to select pulses corresponding to ..cap alpha..- and b-particles, and delayed coincidence circuits of a recording element separate and record b-..cap alpha.. and ..cap alpha..-..cap alpha.. cascade pairs of delayed coincidences of RaC, ThC, and AcA radionuclides. Flows are measured twice at a predetermined time interval to account for emanation build-up tendency and concentration of isotopes of radium is determined from a formula.

  9. Characterising the exchangeability of phenanthrene associated with naturally occurring soil colloids using an isotopic dilution technique.

    PubMed

    Tavakkoli, Ehsan; Juhasz, Albert; Donner, Erica; Lombi, Enzo

    2015-04-01

    The association of polycyclic aromatic hydrocarbons (PAHs) with inorganic and organic colloids is an important factor influencing their bioavailability, mobility and degradation in the environment. Despite this, our understanding of the exchangeability and potential bioavailability of PAHs associated with colloids is limited. The objective of this study was to use phenanthrene as a model PAH compound and develop a technique using (14)C phenanthrene to quantify the isotopically exchangeable and non-exchangeable forms of phenanthrene in filtered soil water or sodium tetraborate extracts. The study was also designed to investigate the exchangeability of colloidal phenanthrene as a function of particle size. Our findings suggest that the exchangeability of phenanthrene in sodium tetraborate is controlled by both inorganic and organic colloids, while in aqueous solutions inorganic colloids play the dominant role (even though coating of these by organic matter cannot be excluded). Filter pore size did not have a significant effect on phenanthrene exchangeability. PMID:25689461

  10. Combining metagenomics with metaproteomics and stable isotope probing reveals metabolic pathways used by a naturally occurring marine methylotroph.

    PubMed

    Grob, Carolina; Taubert, Martin; Howat, Alexandra M; Burns, Oliver J; Dixon, Joanna L; Richnow, Hans H; Jehmlich, Nico; von Bergen, Martin; Chen, Yin; Murrell, J Colin

    2015-10-01

    A variety of culture-independent techniques have been developed that can be used in conjunction with culture-dependent physiological and metabolic studies of key microbial organisms in order to better understand how the activity of natural populations influences and regulates all major biogeochemical cycles. In this study, we combined deoxyribonucleic acid-stable isotope probing (DNA-SIP) with metagenomics and metaproteomics to characterize an uncultivated marine methylotroph that actively incorporated carbon from (13) C-labeled methanol into biomass. By metagenomic sequencing of the heavy DNA, we retrieved virtually the whole genome of this bacterium and determined its metabolic potential. Through protein-stable isotope probing, the RuMP cycle was established as the main carbon assimilation pathway, and the classical methanol dehydrogenase-encoding gene mxaF, as well as three out of four identified xoxF homologues were found to be expressed. This proof-of-concept study is the first in which the culture-independent techniques of DNA-SIP and protein-SIP have been used to characterize the metabolism of a naturally occurring Methylophaga-like bacterium in the marine environment (i.e. Methylophaga thiooxydans L4) and thus provides a powerful approach to access the genome and proteome of uncultivated microbes involved in key processes in the environment. PMID:26033676

  11. Comment on ``Existence of long-lived isomeric states in naturally-occurring neutron-deficient Th isotopes''

    NASA Astrophysics Data System (ADS)

    Barber, R. C.; de Laeter, J. R.

    2009-04-01

    In their article Existence of Long-Lived Isomeric States in Naturally-Occuring Neutron-Deficient Th Isotopes [Phys. Rev. C 76, 021303 (2007)], Marinov fail to demonstrate that basic mass spectrometric protocols, such as abundance sensitivity, linearity, and freedom from possible interferences, have been met. In particular, the claim that four isomeric states of Th have been discovered, using an inductively coupled plasma-sector field mass spectrometer (ICP-SFMS), with abundances from (1-10)10-11 relative to Th232, cannot be accepted, given the known abundance sensitivities of other sector field mass spectrometers. Accelerator mass spectrometry is the only mass spectrometric methodology capable of measuring relative abundances of the magnitude claimed by Marinov

  12. Naturally occurring insecticides.

    PubMed Central

    Soloway, S B

    1976-01-01

    Naturally occurring insecticides are abundant and varied in their effects, though but a few are articles of commerce. Even for these, pyrethrum, nicotine, rotenone, hellebore, ryania, and sabadilla, there is a paucity of information on mammalian toxicology and environmental effects. In general, these materials are characterized favorably by low acute toxicity and ready dissipation in nature. Unfavorable aspects of natural insecticides are the contained mixture of active and inactive components and the low active ingredient content on a crop yield basis pointing to a high unit cost. Natural insecticides can serve additionally as leads to unnatural mimics, of which the commercially successful synthetic pyrethroids are prime examples. The chemical nature, relationship of insecticidal activity to chemical structure, occurrence, production, and utilization, registered uses, metabolism, and insect and mammalian toxicity are reviewed. PMID:789058

  13. "Naturally occurring asbestos

    NASA Astrophysics Data System (ADS)

    Cagnard, F.; Lahondère, D.; Blein, O.; Lahfid, A.; Wille, G.

    2012-04-01

    The term asbestos refers to six silicate minerals from amphibole and serpentine groups. By definition, it consists in bundles of thin and flexible long fibers, with high-tensile strength, and chemical and heat resistance. In contrast to asbestos found within commercial products and mining, the specific term ''naturally occurring asbestos'' (NOA) refers to asbestiform minerals occurring within rocks or soils that can be released by human activities or weathering processes. The fact that the exposure to asbestos is related to lung pathologies is now widely demonstrated (e.g. asbestosis, mesothelioma and lung cancer). However, if health risks associated with exposure to NOA exist, they are not yet well documented. The crystallization of natural asbestos occurs in specific Mg-rich lithologies associated with peculiar structural and metamorphic conditions. By recognizing and combining such specific geologic criteria, the presence or the absence of asbestos in bedrock terrains can be reasonably predicted and maps of NOA hazard can be drawn. We present here new results of geological mapping and petrological study concerning the evaluation of the NOA hazard in the Alps and Corsica, in France. The three folds approach consists in (1) a determination of lithologies with potential NOA from a bibliographic compilation and extraction of target zones from a geological geodatabase (2) a geological mapping of the target zones followed by a petrological characterization of sampled asbestiform minerals in the laboratory (optical microscopy, TEM, SEM, and Raman spectroscopy technics), and (3) the drawing of the final map of NOA hazard, at regional-scale. Occurrence criteria can be retained as follows: 1. NOA are abundant in the internal zones of the Alps and Corsica, especially within ophiolitic complexes. Natural asbestos are mostly concentrated within ultramafic rocks but can also occur within basic lithologies such as Mg-metagabbros, metabasalts and meta-pillow-lavas, 2. Asbestos is commonly located within fractures, shear-bands or shear-planes, developed during late retrograde metamorphic history, 3. Tremolite-actinolite-type asbestos is abundant both in ultramafic and mafic rocks, 4. Natural asbestos occur in few places within the external zones of the Alps, especially within hercynian ophiolitic massifs or concentrated in late Alpine fractures affecting leptyno-amphibolic lithologies.

  14. Naturally Occurring Food Toxins

    PubMed Central

    Dolan, Laurie C.; Matulka, Ray A.; Burdock, George A.

    2010-01-01

    Although many foods contain toxins as a naturally-occurring constituent or, are formed as the result of handling or processing, the incidence of adverse reactions to food is relatively low. The low incidence of adverse effects is the result of some pragmatic solutions by the US Food and Drug Administration (FDA) and other regulatory agencies through the creative use of specifications, action levels, tolerances, warning labels and prohibitions. Manufacturers have also played a role by setting limits on certain substances and developing mitigation procedures for process-induced toxins. Regardless of measures taken by regulators and food producers to protect consumers from natural food toxins, consumption of small levels of these materials is unavoidable. Although the risk for toxicity due to consumption of food toxins is fairly low, there is always the possibility of toxicity due to contamination, overconsumption, allergy or an unpredictable idiosyncratic response. The purpose of this review is to provide a toxicological and regulatory overview of some of the toxins present in some commonly consumed foods, and where possible, discuss the steps that have been taken to reduce consumer exposure, many of which are possible because of the unique process of food regulation in the United States. PMID:22069686

  15. Isotopic composition and origin of indigenous natural perchlorate and co-occurring nitrate in the southwestern United States.

    PubMed

    Jackson, W Andrew; Bhlke, John Karl; Gu, Baohua; Hatzinger, Paul B; Sturchio, Neil C

    2010-07-01

    Perchlorate (ClO(4)(-)) has been detected widely in groundwater and soils of the southwestern United States. Much of this ClO(4)(-) appears to be natural, and it may have accumulated largely through wet and dry atmospheric deposition. This study evaluates the isotopic composition of natural ClO(4)(-) indigenous to the southwestern U.S. Stable isotope ratios were measured in ClO(4)(-) (delta(18)O, Delta(17)O, delta(37)Cl) and associated NO(3)(-) (delta(18)O, Delta(17)O, delta(15)N) in groundwater from the southern High Plains (SHP) of Texas and New Mexico and the Middle Rio Grande Basin (MRGB) in New Mexico, from unsaturated subsoil in the SHP, and from NO(3)(-)-rich surface caliche deposits near Death Valley, California. The data indicate natural ClO(4)(-) in the southwestern U.S. has a wide range of isotopic compositions that are distinct from those reported previously for natural ClO(4)(-) from the Atacama Desert of Chile as well as all known synthetic ClO(4)(-). ClO(4)(-) in Death Valley caliche has a range of high Delta(17)O values (+8.6 to +18.4 per thousand), overlapping and extending the Atacama range, indicating at least partial atmospheric formation via reaction with ozone (O(3)). However, the Death Valley delta(37)Cl values (-3.1 to -0.8 per thousand) and delta(18)O values (+2.9 to +26.1 per thousand) are higher than those of Atacama ClO(4)(-). In contrast, ClO(4)(-) from western Texas and New Mexico has much lower Delta(17)O (+0.3 to +1.3 per thousand), with relatively high delta(37)Cl (+3.4 to +5.1 per thousand) and delta(18)O (+0.5 to +4.8 per thousand), indicating either that this material was not primarily generated with O(3) as a reactant or that the ClO(4)(-) was affected by postdepositional O isotope exchange. High Delta(17)O values in ClO(4)(-) (Atacama and Death Valley) are associated with high Delta(17)O values in NO(3)(-), indicating that both compounds preserve characteristics of O(3)-related atmospheric production in hyper-arid settings, whereas both compounds have low Delta(17)O values in less arid settings. Although Delta(17)O variations in terrestrial NO(3)(-) can be attributed to mixing of atmospheric (high Delta(17)O) and biogenic (low Delta(17)O) NO(3)(-), variations in Delta(17)O of terrestrial ClO(4)(-) are not readily explained in the same way. This study provides important new constraints for identifying natural sources of ClO(4)(-) in different environments by multicomponent isotopic characteristics, while presenting the possibilities of divergent ClO(4)(-) formation mechanisms and(or) ClO(4)(-) isotopic exchange in biologically active environments. PMID:20521813

  16. Carcinogens occurring naturally in foods.

    PubMed

    Miller, J A; Miller, E C

    1976-05-01

    Humans are susceptible to the carcinogenic action of a small group of organic and inorganic chemicals in certain industrial, medical, and social habit exposures. A larger number and wider variety of chemical carcinogens, primarily organic compounds, are known for experimental animals. Chemical carcinogens are also found among the metabolites of living cells. No common structure is evident among chemical carcinogens, and a majority of these agents are precarcinogens that require metabolic activation into reactive electrophilic ultimate carcinogens. These strong electrophiles combine covalently with nucleophilic sites in DNAs, RNAs, and proteins in target tissues. One or more of these adducts appear to initiate carcinogenesis. About 20 naturally occurring organic chemical carcinogens, primarily metabolites of green plants and fungi, are known; some occur in some human foods. Many other naturally chemical carcingens doubtless exist among the vast number of uncharacterized nonnutritive minor components of living systems, some of which are sources of human foods. The electrophilic forms of chemical carcinogens are mutagenic, and mammalian tissue-mediated mutagenicity assays appear promising in the detection of potential chemical carcinogens. These assays should serve at least as a prescreen for conventional lifetime tests in rodents for the carcinogenic activity of food components and contaminants. Epidemiological approaches appear necessary to evaluate the importance of the naturally occurring chemical carcinogens in the occurrence of human cancer. PMID:770205

  17. Caffeine, a naturally occurring acaricide.

    PubMed

    Russell, D W; Fernndez-Caldas, E; Swanson, M C; Seleznick, M J; Trudeau, W L; Lockey, R F

    1991-01-01

    Since caffeine is a plant alkaloid that has been described as a naturally occurring insecticide, its acaricidal effect on Dermatophagoides pteronyssinus (Dp) was investigated. Twelve cultures were established by adding 30 Dp to 200 mg of Tetramin fish food and brewer's yeast (8:2 ratio); six cultures were treated with 20 mg of finely ground caffeine. All 12 cultures were incubated at 75% relative humidity, 25 degrees C, and observed during 8 weeks. Live mites were then counted under a stereoscope, cultures were extracted, and supernatants were analyzed for Der p I and Der f I allergen content with a two-site monoclonal RIA. Live mite counts in untreated cultures varied from 146 to 274 (215 +/- 47.1), and in caffeine-treated cultures from 0 to 3 (1 +/- 1.2; p less than or equal to 0.0001). Der p I concentrations in untreated cultures varied from 588 to 9000 ng/gm (3138.3 +/- 2990.8 ng/gm), and in caffeine-treated cultures from 52 to 117 ng/gm (78 +/- 23.8 ng/gm; p less than or equal to 0.01). Der p I was not detected in the food media or caffeine; Der f I was not detected in any of the cultures. Results demonstrate that caffeine inhibits mite growth and allergen production. PMID:1991914

  18. INACTIVATION OF NATURALLY OCCURRING ENTEROVIRUSES

    EPA Science Inventory

    The goal of this project was to compare the kinetics of chlorine inactivation of a naturally-shed virus and its tissue culture grown counterpart. Since inactivation studies require purified preparation possessing high infectivity titer and low chlorine demand a major part of this...

  19. The magnitude of the naturally occurring isotopic enrichment of 13C in exhaled CO2 is directly proportional to exercise intensity in humans.

    PubMed

    McCue, Marshall D; Passement, Celeste A; Rodriguez, Miranda

    2015-01-01

    Due to various biochemical fractionation processes during lipid synthesis, the lipid molecules in the body contain substantially lower concentrations of 13C than the nonlipid molecules. Because of the isotopic differences between these two endogenous nutrient pools, any shift toward nonlipid fuel oxidation would be expected to increase in the ?13C of the exhaled breath. Interestingly, the possibility of whether or not an exercise-induced change actually occurs has been debated in literature for over two decades and researchers have still not reached a consensus. We measured ventilatory and metabolic variables before, during, and after exercise in forty-eight adults (n = 25 females, n = 23 males; 20.1 1.9 years) assigned to either a resting treatment or one of three exercising treatments where they maintained a heart rate of 130, 150, or 170 bpm for 56 min. We found that the mean metabolic rates of the exercising groups increased 4.4-fold, 6.1-fold, and 7.7-fold above resting values, respectively. Exercise caused small increases in respiratory exchange ratios (e.g., from 0.83 0.08 to 0.86 0.10) indicative of increased carbohydrate oxidation, but these changes were too variable to be reliably correlated with exercise intensity. In contrast, the ?13C of the exhaled breath increased by 0.62 0.19, 1.14 0.29, and 1.79 0.50, respectively, for the three groups and was significantly correlated with the intensity of exercise. We also show that the isotopic difference of the lipid and nonlipids of the body is similar (~ 2.7) even when consuming bulk diets that are isotopically distinct (> 8). If not corrected for, these exercise-induced changes in ?13C of the breath would be sufficiently large to skew the results of studies investigating the oxidative fates of exogenous nutritional supplements. PMID:25446144

  20. Biodegradation Monitored Natural Attenuation (MNA) for Oxygenates: How it Evolved, why it Occurs and Using Stable Carbon Isotopes to Predict Plume Behavior

    EPA Science Inventory

    The organisms that degrade MtBE under anaerobic conditions are evolved to acquire energy for growth by using molecular hydrogen and carbonate ion to cleave methyl ether bonds. Methyl ether bonds are common in nature and the bond also occurs in MTBE. MTBE in contaminated ground...

  1. Biodegradation – Monitored Natural Attenuation (MNA) for Oxygenates: How it Evolved, why it Occurs and Using Stable Carbon Isotopes to Predict Plume Behavior

    EPA Science Inventory

    The organisms that degrade MtBE under anaerobic conditions are evolved to acquire energy for growth by using molecular hydrogen and carbonate ion to cleave methyl ether bonds. Methyl ether bonds are common in nature and the bond also occurs in MTBE. MTBE in contaminated ground...

  2. Stable Isotopes of Selenium and Common Elements (N, O, S) Reveal Redox Controls on the Mobility of a Naturally Occurring Source of Selenium

    NASA Astrophysics Data System (ADS)

    Andrus, R. E.; Hibbs, B.; Ellis, A.

    2007-12-01

    Historically, an extensive wetland known as the "Swamp of the Frogs" occupied the central, low-lying part of the San Diego Creek Watershed in Orange County, California. The swamp acted as a sink for the redox sensitive trace element selenium. Toward the end of the nineteenth century the swamp was drained to make way for the expansion of ranching and agriculture, resulting in a shift in prevailing redox conditions. High levels selenium have been reported in the shallow groundwaters associated with the historic swamp often causing surface water concentrations to exceed the EPA chronic criterion of 5 ug/L. Nitrate in groundwater often exceeds 10 mg/L NO3-N due to leaching of fertilizer used on citrus crops. Published research has shown that nitrate can act to oxidize reduced forms of sulfur and selenium. Stable isotopes of selenium, N and O in nitrate and S in sulfate are used to investigate the link between denitrification and the oxidation of reduced forms of sulfur and selenium along two groundwater flowpaths within the historic swamp. The "El Modena" flowpath begins roughly at the northern boundary of the historic swamp. Along this flowpath selenium increases from an upgradient value of 12 ug/L to a downgradient value of 80 ug/L while nitrate varies from 16 to 28 mg/L NO3-N. Isotopes of N and O in nitrate indicate a denitrification trend along the flowpath as delta 15N [NO3-] increases from 6.8 per mille to 19.0 per mille and delta 18O [NO3-] increases from 6.8 per mille to 14.0 per mille. The behavior of sulfur isotopes varies inversely with that of nitrogen with delta 34S [SO4 2-] decreasing from 0.1 per mille to -17.2 per mille. This, coupled with a slight enrichment in delta 13C-DIC, suggests that denitrification is coupled to the oxidation of metal sulfides disseminated in soils. Selenium isotopes (del 82/76Se [SeO4 2-]) did not grow isotopically depleted as expected, but varied from about 1.0 per mille at the outer boundary of the historic marsh, decreasing to about -1.0 per mille as groundwater moves slightly inside the marsh interior, increasing to about 2.3 per mille toward the end of the flowpath, deep within the historic marsh. The relative availability of sulfur and selenium may explain the observed pattern in selenium isotopes. The "Valencia" flowpath begins roughly at the southeast boundary of the historic swamp. Selenium increases from an upgradient value of 42 ug/L to a downgradient value of 141 ug/L while nitrate varies from 13 to 18 mg/L NO3-N. Groundwaters flowing along this flowpath did not show a change in isotope ratios. Neither delta 34S [SO4 2-] nor delta 15N [NO3-] and delta 18O [NO3-] vary by more than 1 per mille, which is small enough to discount a role of redox processes. Anomalously high concentrations of silica along this flowpath may point to a possible explanation for this result.

  3. Synthesis of Naturally Occurring Tropones and Tropolones

    PubMed Central

    Liu, Na; Song, Wangze; Schienebeck, Casi M.; Zhang, Min; Tang, Weiping

    2014-01-01

    Tropones and tropolones are an important class of seven-membered non-benzenoid aromatic compounds. They can be prepared directly by oxidation of seven-membered rings. They can also be derived from cyclization or cycloaddition of appropriate precursors followed by elimination or rearrangement. This review discusses the types of naturally occurring tropones and tropolones and outlines important methods developed for the synthesis of tropone and tropolone natural products. PMID:25400298

  4. Naturally occurring antimicrobials for minimally processed foods.

    PubMed

    Davidson, P Michael; Critzer, Faith J; Taylor, T Matthew

    2013-01-01

    Natural antimicrobials are gaining increased interest from researchers and food manufacturers alike seeking to discover label-friendly alternatives to the widely implemented synthetic compounds. Naturally occurring antimicrobials can be applied directly to food to protect food quality, extend food shelf life by inhibiting or inactivating spoilage microorganisms, and improve food safety by inhibiting or inactivating food-borne pathogens. There are a great number of natural antimicrobials derived from animal, plant, and microbial sources. This manuscript reviews their efficacy against spoilage and pathogenic organisms, their methods of evaluation, and their application in various foods as well as the development of novel delivery systems and incorporation with other hurdles. PMID:23244398

  5. Naturally occurring products in cancer therapy

    PubMed Central

    Rajesh, E.; Sankari, Leena S.; Malathi, L.; Krupaa, Jayasri R.

    2015-01-01

    Natural products have been used for the treatment of various diseases and are becoming an important research area for drug discovery. These products, especially phytochemicals have been extensively studies and have exhibited anti-carcinogenic activities by interfering with the initiation, development and progression of cancer through the modulation of various mechanisms including cellular proliferation, differentiation, apoptosis, angiogenesis, and metastasis. This concept is gaining attention because it is a cost-effective alternative to cancer treatment. In this article, we have discussed some of the naturally occurring products used in cancer treatment. PMID:26015704

  6. Naturally Occuring Fish Poisons from Plants

    NASA Astrophysics Data System (ADS)

    Cannon, Jonathan G.; Burton, Robert A.; Wood, Steven G.; Owen, Noel L.

    2004-10-01

    Since prehistoric times, cultures throughout the world have used piscicidal (fish poisoning) plants for fishing. In recent times, scientists have identified many of the plant compounds responsible for killing the fish and have found that these compounds possess other important biological properties, such as insecticidal and anti-cancer activities. This article reviews some of the chemical research that has been performed on naturally occurring fish poisons, including plant sources, methods of use, toxicity, and mechanisms of action of piscicides.

  7. Introduction to naturally occurring radioactive material

    SciTech Connect

    Egidi, P.

    1997-08-01

    Naturally occurring radioactive material (NORM) is everywhere; we are exposed to it every day. It is found in our bodies, the food we eat, the places where we live and work, and in products we use. We are also bathed in a sea of natural radiation coming from the sun and deep space. Living systems have adapted to these levels of radiation and radioactivity. But some industrial practices involving natural resources concentrate these radionuclides to a degree that they may pose risk to humans and the environment if they are not controlled. Other activities, such as flying at high altitudes, expose us to elevated levels of NORM. This session will concentrate on diffuse sources of technologically-enhanced (TE) NORM, which are generally large-volume, low-activity waste streams produced by industries such as mineral mining, ore benefication, production of phosphate Fertilizers, water treatment and purification, and oil and gas production. The majority of radionuclides in TENORM are found in the uranium and thorium decay chains. Radium and its subsequent decay products (radon) are the principal radionuclides used in characterizing the redistribution of TENORM in the environment by human activity. We will briefly review other radionuclides occurring in nature (potassium and rubidium) that contribute primarily to background doses. TENORM is found in many waste streams; for example, scrap metal, sludges, slags, fluids, and is being discovered in industries traditionally not thought of as affected by radionuclide contamination. Not only the forms and volumes, but the levels of radioactivity in TENORM vary. Current discussions about the validity of the linear no dose threshold theory are central to the TENORM issue. TENORM is not regulated by the Atomic Energy Act or other Federal regulations. Control and regulation of TENORM is not consistent from industry to industry nor from state to state. Proposed regulations are moving from concentration-based standards to dose-based standards. So when is TENORM a problem? Where is it a problem? That depends on when, where, and whom you talk to! We will start by reviewing background radioactivity, then we will proceed to the geology, mobility, and variability of these radionuclides. We will then review some of the industrial sectors affected by TENORM, followed by a brief discussion on regulatory aspects of the issue.

  8. Sundew adhesive: a naturally occurring hydrogel.

    PubMed

    Huang, Yujian; Wang, Yongzhong; Sun, Leming; Agrawal, Richa; Zhang, Mingjun

    2015-06-01

    Bioadhesives have drawn increasing interest in recent years, owing to their eco-friendly, biocompatible and biodegradable nature. As a typical bioadhesive, sticky exudate observed on the stalked glands of sundew plants aids in the capture of insects and this viscoelastic adhesive has triggered extensive interests in revealing the implied adhesion mechanisms. Despite the significant progress that has been made, the structural traits of the sundew adhesive, especially the morphological characteristics in nanoscale, which may give rise to the viscous and elastic properties of this mucilage, remain unclear. Here, we show that the sundew adhesive is a naturally occurring hydrogel, consisting of nano-network architectures assembled with polysaccharides. The assembly process of the polysaccharides in this hydrogel is proposed to be driven by electrostatic interactions mediated with divalent cations. Negatively charged nanoparticles, with an average diameter of 231.9 14.8 nm, are also obtained from this hydrogel and these nanoparticles are presumed to exert vital roles in the assembly of the nano-networks. Further characterization via atomic force microscopy indicates that the stretching deformation of the sundew adhesive is associated with the flexibility of its fibrous architectures. It is also observed that the adhesion strength of the sundew adhesive is susceptible to low temperatures. Both elasticity and adhesion strength of the sundew adhesive reduce in response to lowering the ambient temperature. The feasibility of applying sundew adhesive for tissue engineering is subsequently explored in this study. Results show that the fibrous scaffolds obtained from sundew adhesive are capable of increasing the adhesion of multiple types of cells, including fibroblast cells and smooth muscle cells, a property that results from the enhanced adsorption of serum proteins. In addition, in light of the weak cytotoxic activity exhibited by these scaffolds towards a variety of mammal cells, evidence is sufficient to propose that sundew adhesive is a promising nanomaterial worth further exploitation in the field of tissue engineering. PMID:25948615

  9. Naturally occurring reoviruses for human cancer therapy

    PubMed Central

    Kim, Manbok

    2015-01-01

    Naturally occurring reoviruses are live replication-proficient viruses that specifically infect human cancer cells while sparing their normal counterpart. Since the discovery of reoviruses in 1950s, they have shown various degrees of safety and efficacy in pre-clinical or clinical applications for human anti-cancer therapeutics. I have recently discovered that cellular tumor suppressor genes are also important in determining reoviral tropism. Carcinogenesis is a multi-step process involving the accumulation of both oncogene and tumor suppressor gene abnormalities. Reoviruses can exploit abnormal cellular tumor suppressor signaling for their oncolytic specificity and efficacy. Many tumor suppressor genes such as p53, ataxia telangiectasia mutated (ATM), and retinoblastoma associated (RB) are known to play important roles in genomic fidelity/maintenance. Thus, a tumor suppressor gene abnormality could affect host genomic integrity and likely disrupt intact antiviral networks due to the accumulation of genetic defects which in turn could result in oncolytic reovirus susceptibility. This review outlines the discovery of oncolytic reovirus strains, recent progresses in elucidating the molecular connection between oncogene/tumor suppressor gene abnormalities and reoviral oncotropism, and their clinical implications. Future directions in the utility of reovirus virotherapy is also proposed in this review. [BMB Reports 2015; 48(8): 454-460] PMID:26058397

  10. Naturally occurring contamination in the Mancos Shale.

    PubMed

    Morrison, Stan J; Goodknight, Craig S; Tigar, Aaron D; Bush, Richard P; Gil, April

    2012-02-01

    Some uranium mill tailings disposal cells were constructed on dark-gray shale of the Upper Cretaceous Mancos Shale. Shale of this formation contains contaminants similar to those in mill tailings. To establish the contributions derived from the Mancos, we sampled 51 locations in Colorado, New Mexico, and Utah. Many of the groundwater samples were saline with nitrate, selenium, and uranium concentrations commonly exceeding 250,?000, 1000, and 200 ?g/L, respectively. Higher concentrations were limited to groundwater associated with shale beds, but were not correlated with geographic area, stratigraphic position, or source of water. The elevated concentrations suggest that naturally occurring contamination should be considered when evaluating groundwater cleanup levels. At several locations, seep water was yellow or red, caused in part by dissolved organic carbon concentrations up to 280 mg/L. Most seeps had (234)U to (238)U activity ratios greater than 2, indicating preferential leaching of (234)U. Seeps were slightly enriched in (18)O relative to the meteoric water line, indicating limited evaporation. Conceptually, major ion chemical reactions are dominated by calcite dissolution following proton release from pyrite oxidation and subsequent exchange by calcium for sodium residing on clay mineral exchange sites. Contaminants are likely released from organic matter and mineral surfaces during weathering. PMID:22225529

  11. Naturally occurring flavonoids against human norovirus surrogates.

    PubMed

    Su, Xiaowei; D'Souza, Doris H

    2013-06-01

    Naturally occurring plant-derived flavonoids are reported to have antibacterial, antiviral, and pharmacological activities. The objectives of this study were to determine the antiviral effects of four flavonoids (myricetin, L-epicatechin, tangeretin, and naringenin) on the infectivity of food borne norovirus surrogates after 2 h at 37 °C. The lab-culturable surrogates, feline calicivirus (FCV-F9) at titers of ~7 log₁₀ PFU/ml (high titer) or ~5 log₁₀ PFU/ml (low titer) and murine norovirus (MNV-1) at ~5 log₁₀ PFU/ml, were mixed with equal volumes of myricetin, L-epicatechin, tangeretin, or naringenin at concentrations of 0.5 or 1 mM, and incubated for 2 h at 37 °C. Treatments of viruses were neutralized in cell culture medium containing 10 % heat-inactivated fetal bovine serum, serially diluted, and plaque assayed. Each treatment was replicated thrice and assayed in duplicate. FCV-F9 (low titer) was not found to be reduced by tangeretin or naringenin, but was reduced to undetectable levels by myricetin at both concentrations. Low titer FCV-F9 was also decreased by 1.40 log₁₀ PFU/ml with L-epicatechin at 0.5 mM. FCV-F9 at high titers was decreased by 3.17 and 0.72 log₁₀ PFU/ml with myricetin and L-epicatechin at 0.5 mM, and 1.73 log10 PFU/ml with myricetin at 0.25 mM, respectively. However, MNV-1 showed no significant inactivation by the four tested treatments. The antiviral effects of the tested flavonoids are dependent on the virus type, titer, and dose. Further research will focus on understanding the antiviral mechanism of myricetin and L-epicatechin. PMID:23412728

  12. Tetrahedral boron in naturally occurring tourmaline

    SciTech Connect

    Tagg, S.L.; Cho, H.; Dyar, M.D.; Grew, E.S.

    1999-09-01

    Evidence for boron in both trigonal and tetrahedral coordination has been found in {sup 11}B magic-angle-spinning (MAS) nuclear magnetic resonance (NMR) spectra of natural, inclusion-free specimens of aluminum-rich lithian tourmaline from granitic pregmatites.

  13. Naturally Occurring Fish Poisons from Plants

    ERIC Educational Resources Information Center

    Cannon, Jonathan G.; Burton, Robert A.; Wood, Steven G.; Owen, Noel L.

    2004-01-01

    The fish poisons derived from plants used throughout the world, not only as piscicides but also for a range of other uses, including insecticident and in folk medicines, is presented. The aim of this review is to provide a useful background for students interested in natural products.

  14. Dog Models of Naturally Occurring Cancer

    PubMed Central

    Rowell, Jennie L.; McCarthy, Donna O.; Alvarez, Carlos E.

    2011-01-01

    Studies using dogs provide an ideal solution to the gap in animal models of natural disease and translational medicine. This is evidenced by approximately 400 inherited disorders being characterized in domesticated dogs, most of which are relevant to humans. There are several hundred isolated populations of dogs (breeds) and each has vastly reduced genetic variation compared to humans; this simplifies disease mapping and pharmacogenomics. Dogs age five to eight-fold faster than humans, share environments with their owners, are usually kept until old age, and receive a high level of health care. Farseeing investigators recognized this potential and, over the last decade, developed the necessary tools and infrastructure to utilize this powerful model of human disease, including the sequencing of the dog genome in 2005. Here we review the nascent convergence of genetic and translational canine models of spontaneous disease, focusing on cancer. PMID:21439907

  15. Naturally occurring hydroxytyrosol: synthesis and anticancer potential.

    PubMed

    Bernini, R; Merendino, N; Romani, A; Velotti, F

    2013-01-01

    Several epidemiological and animal studies have suggested that polyphenols, a group of secondary plant metabolites occurring mainly in the plant kingdom, may have a protective effect against some chronic degenerative diseases such as cancer. Polyphenols are part of the human diet, being present in vegetal food and beverages. Among them, an olive biophenol named hydroxytyrosol [2-(3,4- dihydroxyphenyl)ethanol, HTyr] has recently received particular attention because of its antioxidant, antiproliferative, pro-apoptotic, and anti-inflammatory activities, which have the potential to specifically counteract all cancer hallmarks, thus representing the expectant biological activities underlying the anti-tumor properties of this polyphenol. After a description of the synthetic procedures to prepare pure HTyr, this review takes into consideration the chemopreventive and chemotherapeutic potential of HTyr as the result of its antioxidant, antiproliferative and anti-inflammatory activities. In particular, the review is focused on the current knowledge of the main cellular and molecular mechanisms used by HTyr to affect carcinogenesis, highlighting the specific oncogenic and inflammatory signaling pathways potentially targeted by HTyr. PMID:23244583

  16. Absolute configuration of naturally occurring glabridin.

    PubMed

    Simmler, Charlotte; Fronczek, Frank R; Pauli, Guido F; Santarsiero, Bernard D

    2013-11-01

    The title compound {systematic name: 4-[(3R)-8,8-dimethyl-3,4-dihydro-2H-pyrano[2,3-f]chromen-3-yl]benzene-1,3-diol, commonly named glabridin}, C20H20O4, is a species-specific biomarker from the roots Glycyrrhiza glabra L. (European licorice, Fabaceae). In the present study, this prenylated isoflavan has been purified from an enriched CHCl3 fraction of the extract of the root, using three steps of medium-pressure liquid chromatography (MPLC) by employing HW-40F, Sephadex LH-20 and LiChroCN as adsorbents. Pure glabridin was crystallized from an MeOH-H2O mixture (95:5?v/v) to yield colorless crystals containing one molecule per asymmetric unit (Z' = 1) in the space group P212121. Although the crystal structure has been reported before, the determination of the absolute configuration remained uncertain. Stereochemical analysis, including circular dichroism, NMR data and an X-ray diffraction data set with Bijvoet differences, confirms that glabridin, purified from its natural source, is found only in a C3 R configuration. These results can therefore be used as a reference for the assignment of the configuration and enantiopurity of any isolated or synthetic glabridin sample. PMID:24192160

  17. Uranium isotopes in groundwater occurring at Amazonas State, Brazil.

    PubMed

    da Silva, Mrcio Luiz; Bonotto, Daniel Marcos

    2015-03-01

    This paper reports the behavior of the dissolved U-isotopes (238)U and (234)U in groundwater providing from 15 cities in Amazonas State, Brazil. The isotope dilution technique accompanied by alpha spectrometry were utilized for acquiring the U content and (234)U/(238)U activity ratio (AR) data, 0.01-1.4gL(-1) and 1.0-3.5, respectively. These results suggest that the water is circulating in a reducing environment and leaching strata containing minerals with low uranium concentration. A tendency to increasing ARs values following the groundwater flow direction is identified in Manaus city. The AR also increases according to the SW-NE directions: Uarini?Tef; Manacapuru?Manaus; Presidente Figueiredo?So Sebastio do Uatum; and Boa Vista do Ramos?Parintins. Such trends are possibly related to several factors, among them the increasing acid character of the waters. The waters analyzed are used for human consumption and the highest dissolved U content is much lower than the maximum established by the World Health Organization. Therefore, in view of this radiological parameter they can be used for drinking purposes. PMID:25528017

  18. Stable Carbon Isotopic Signatures and Fractionations Occurring During Fungal Biosynthesis of Methyl Chloride

    NASA Astrophysics Data System (ADS)

    Shaw, S. L.; Henn, M. R.; Chapela, I. H.; Conrad, M. E.; Goldstein, A. H.

    2003-12-01

    Methyl halides are responsible for approximately 25% of the equivalent chlorine involved in stratospheric ozone depletion, yet quantitative understanding of their atmospheric budgets is still incomplete. The use of an isotopic mass balance to constrain these budgets is currently being investigated. The utility of this approach will depend not only on being able to measure the source signatures and loss kinetic isotope effects contributing to their atmospheric budgets, but also in our ability to assess the variability in these terms. Natural methyl halide sources and sinks due to microbial cycling, combined with their large and variable associated isotopic effects, should have discernable effects on the global atmospheric signature of these gases. Thus, we have begun investigating the isotopic signatures of methyl halides produced by fungi, and the fractionations occurring during their biosynthesis, using controlled laboratory cultures. Measurements of the stable carbon isotopic signatures of growth medium, biomass, respired CO2, CH3Cl, and the carbon mass balance were made over the growth cycle of Inonotus andersonii, a wood-rot fungus previously shown to emit methyl halides. Resulting CH3Cl δ 13C signatures were enriched by approximately 10\\permil as compared to those previously reported for Phellinus pomaceus, another wood-rot species1. Fractionations between substrate and biomass \\{ɛ s-b\\}, as well as biomass and gases \\{ɛ b-g\\}, were nearly constant during exponential and early stationary phase growth. Biomass was depleted by 1\\permil compared to the 13C malt extract medium, and CH3Cl and CO2 were depleted by up to 5\\permil compared to the biomass, implying the bulk of the final CH3Cl signature is determined during CH3Cl synthesis and not during uptake of the carbon substrate. However, the magnitude of these fractionations, and the direction of ɛ s-b, probably depends on the complexity of the substrate. Additionally, a survey of isotopic signatures of CH3Cl produced by several fungal species on C3 and C4 substrates was begun to quantify likely variability in the natural source signature. 1 Harper, DB., R.M. Kalin, J.T.G. Hamilton, and C. Lamb, Carbon Isotope Ratios for Chloromethane of Biological Origin: Potential Tool in Determining Biological Emissions, Environ. Sci.Technol., 35, 3616-3619, 2001.

  19. Stable isotope deltas: tiny, yet robust signatures in nature.

    PubMed

    Brand, Willi A; Coplen, Tyler B

    2012-09-01

    Although most of them are relatively small, stable isotope deltas of naturally occurring substances are robust and enable workers in anthropology, atmospheric sciences, biology, chemistry, environmental sciences, food and drug authentication, forensic science, geochemistry, geology, oceanography, and paleoclimatology to study a variety of topics. Two fundamental processes explain the stable isotope deltas measured in most terrestrial systems: isotopic fractionation and isotope mixing. Isotopic fractionation is the result of equilibrium or kinetic physicochemical processes that fractionate isotopes because of small differences in physical or chemical properties of molecular species having different isotopes. It is shown that the mixing of radioactive and stable isotope end members can be modelled to provide information on many natural processes, including (14)C abundances in the modern atmosphere and the stable hydrogen and oxygen isotopic compositions of the oceans during glacial and interglacial times. The calculation of mixing fractions using isotope balance equations with isotope deltas can be substantially in error when substances with high concentrations of heavy isotopes (e.g. (13)C, (2)H, and (18)O ) are mixed. In such cases, calculations using mole fractions are preferred as they produce accurate mixing fractions. Isotope deltas are dimensionless quantities. In the International System of Units (SI), these quantities have the unit 1 and the usual list of prefixes is not applicable. To overcome traditional limitations with expressing orders of magnitude differences in isotope deltas, we propose the term urey (symbol Ur), after Harold C. Urey, for the unit 1. In such a manner, an isotope delta value expressed traditionally as-25 per mil can be written as-25 mUr (or-2.5 cUr or-0.25 dUr; the use of any SI prefix is possible). Likewise, very small isotopic differences often expressed in per meg 'units' are easily included (e.g. either+0.015 ‰ or+15 per meg can be written as+15 μUr. PMID:22462621

  20. Stable isotope deltas: Tiny, yet robust signatures in nature

    USGS Publications Warehouse

    Brand, Willi A.; Coplen, Tyler B.

    2012-01-01

    Although most of them are relatively small, stable isotope deltas of naturally occurring substances are robust and enable workers in anthropology, atmospheric sciences, biology, chemistry, environmental sciences, food and drug authentication, forensic science, geochemistry, geology, oceanography, and paleoclimatology to study a variety of topics. Two fundamental processes explain the stable isotope deltas measured in most terrestrial systems: isotopic fractionation and isotope mixing. Isotopic fractionation is the result of equilibrium or kinetic physicochemical processes that fractionate isotopes because of small differences in physical or chemical properties of molecular species having different isotopes. It is shown that the mixing of radioactive and stable isotope end members can be modelled to provide information on many natural processes, including 14C abundances in the modern atmosphere and the stable hydrogen and oxygen isotopic compositions of the oceans during glacial and interglacial times. The calculation of mixing fractions using isotope balance equations with isotope deltas can be substantially in error when substances with high concentrations of heavy isotopes (e.g. 13C, 2H, and 18O ) are mixed. In such cases, calculations using mole fractions are preferred as they produce accurate mixing fractions. Isotope deltas are dimensionless quantities. In the International System of Units (SI), these quantities have the unit 1 and the usual list of prefixes is not applicable. To overcome traditional limitations with expressing orders of magnitude differences in isotope deltas, we propose the term urey (symbol Ur), after Harold C. Urey, for the unit 1. In such a manner, an isotope delta value expressed traditionally as−25 per mil can be written as−25 mUr (or−2.5 cUr or−0.25 dUr; the use of any SI prefix is possible). Likewise, very small isotopic differences often expressed in per meg ‘units’ are easily included (e.g. either+0.015 ‰ or+15 per meg can be written as+15 μUr.

  1. Comparative Toxicology of Libby Amphibole and Naturally Occurring Asbestos

    EPA Science Inventory

    Summary sentence: Comparative toxicology of Libby amphibole (LA) and site-specific naturally occurring asbestos (NOA) provides new insights on physical properties influencing health effects and mechanisms of asbestos-induced inflammation, fibrosis, and tumorigenesis.Introduction/...

  2. Naturally occurring and forced azimuthal modes in a turbulent jet

    NASA Technical Reports Server (NTRS)

    Raman, Ganesh; Rice, Edward J.; Reshotko, Eli

    1991-01-01

    Naturally occurring instability modes in an axisymmetric jet are studied utilizing the modal frequency spectrum method. In the early evolution of the jet the axisymmetric mode was predominant, with the azimuthal modes growing quickly but dominating only after the end of the potential core. The growth of the azimuthal modes is seen nearer to the nozzle exit for the jet in the laminar boundary layer case than for the turbulent. Based on the results from these naturally occurring jet instability mode tests, target modes for efficient excitation were determined and two cases of excitation were examined.

  3. Controlled fermentation of kimchi using naturally occurring antimicrobial agents.

    PubMed

    Kim, Jinsol; Bang, Jihyun; Beuchat, Larry R; Kim, Hoikyung; Ryu, Jee-Hoon

    2012-10-01

    Kimchi is a traditional Korean fermented food. Since it ferments continuously during distribution and storage, the extension of shelf life by preventing over-acidification is a major concern in the kimchi industry. One of the most frequently attempted ways to delay fermentation is to add naturally occurring antimicrobial agents. Many researchers have investigated ways to delay over-acidification by adding minor ingredients, fruits or fruit seed extracts, extracts of medicinal herbs, culinary herbs and spices, and other miscellaneous substances to kimchi. The addition of naturally occurring antimicrobial agents may enhance the acceptability of kimchi to consumers over a longer period of time but may also have a disadvantage in that it may cause changes in sensory quality, especially if added in large amounts. To avoid undesirable sensory changes, application of hurdle technologies (i.e., multifactor preservative systems) which involve using combinations of low amounts of various naturally occurring antimicrobial agents as ingredients should be explored with the goal of controlling fermentation. If synergistic or additive antimicrobial effects can be achieved using small amounts of a combination of natural agents, changes in sensory qualities will be minimized, thereby prolonging shelf life. Research findings summarized in this review provide a basis for developing effective hurdle technologies using naturally occurring antimicrobial agents to extend shelf life of kimchi and perhaps other types of traditional fermented foods. PMID:22850370

  4. A preliminary evaluation of naturally occurring radioactivity concentration levels across the State of Kuwait.

    PubMed

    Shams, H; Bajoga, A D; Alazemi, N; Bradley, D A; Regan, P H

    2016-03-01

    An evaluation of naturally occurring radioactive materials has been undertaken as part of a systematic study to provide a surface radiological map of the State of Kuwait. Soil samples were collected from twelve locations across Kuwait and analysed using high-resolution gamma-ray spectrometry. The (226)Ra and (235)U specific activity concentrations have been determined and used to estimate the (235)U/(238)U isotopic ratios which are found to be comparable to that expected for naturally occurring uranium material. PMID:26717795

  5. The Assessment of Attachment in a Naturally Occurring Strange Situation.

    ERIC Educational Resources Information Center

    Hoyer, Paulette J.; Jacobson, Joseph L.

    Patterns of attachment in preschool-age children were investigated in a nonexperimental, naturally occurring stressful situation. The sample included 86 families with at least one child 18 to 54 months of age. In each family, the mother planned to deliver another child in a hospital birthing center. Separation from the mother during admission was

  6. On the Role of Attention in Naturally Occurring Matching Relations

    ERIC Educational Resources Information Center

    St. Peter, Claire C.; Vollmer, Timothy R.; Bourret, Jason C.; Borrero, Carrie S. W.; Sloman, Kimberly N.; Rapp, John T.

    2005-01-01

    Prior researchers have evaluated the efficacy of using the matching law to describe naturally occurring behavior-environment interactions. However, spurious matching could be obtained if the response and environmental event were correlated, even if the event did not reinforce the response. To assess the likelihood of obtaining spurious matching…

  7. Synthetic procedures for the preparation of deuterium-labeled analogs of naturally occurring steroids

    SciTech Connect

    Wudy, S.A. )

    1990-10-01

    The object of this article is to review the procedures that have been published concerning the preparation of deuterium-labeled analogs of naturally occurring steroid hormones. In combination with mass spectrometric methods, these stable isotope-labeled compounds should be applicable for human metabolism studies or as internal standards. Deuteration techniques for the elucidation of stereochemical problems, procedures for the preparation of monodeuterated steroids, and synthesis of deuterated analogs of nonbiologic steroids have therefore not been included in this review. 41 refs.

  8. Measuring and Modeling Naturally Occurring Radioactive Material: Interpreting the Relationship Between the Natural Radionuclides Present

    SciTech Connect

    Lombardo, A.J.; Mucha, A.F.

    2008-07-01

    The regulatory release of sites and facilities (property) for restricted or unrestricted use has evolved beyond prescribed levels to model-derived dose and risk based limits. Dose models for deriving corresponding soil and structure radionuclide concentration guidelines are necessarily simplified representations of complex processes. A conceptual site model is often developed to present a reasonable and somewhat conservative representation of the physical and chemical properties of the impacted material. Dose modeling software is then used to estimate resulting dose and/or radionuclide specific acceptance criteria (activity concentrations). When the source term includes any or all of the uranium, thorium or actinium natural decay series radionuclides the interpretation of the relationship between the individual radionuclides of the series is critical to a technically correct and complete assessment of risk and/or derivation of radionuclide specific acceptance criteria. Unlike man-made radionuclides, modeling and measuring naturally occurring radioactive material (NORM) and technologically enhanced NORM (TENORM) source terms involves the interpretation of the relationship between the radionuclide present, e.g., secular equilibrium, enrichment, depletion or transient equilibrium. Isotopes of uranium, radium, and thorium occur in all three natural decay series. Each of the three series also produces a radon gas isotope as one of its progeny. In nature, the radionuclides in the three natural decay series are in a state that is approaching or has achieved secular equilibrium, in which the activities of all radionuclides within each series are nearly equal. However, ores containing the three natural decay series may begin in approximate secular equilibrium, but after processing, equilibrium may be broken and certain elements (and the radioactive isotopes of that element) may be concentrated or removed. Where the original ore may have contained one long chain of natural decay series radionuclides, the resulting TENORM source term may contain several smaller decay chains, each headed by a different longer lived member of the original series. This paper presents the anatomy of common TENORM source terms and the pitfalls of measuring, interpreting and modeling these source terms. Modeling TENORM with common software such as RESRAD is discussed. In summary: RESRAD modeling (dose assessments) to derive single radionuclide, dose based acceptance criteria, requires a good understanding of the physical, chemical and biological factors/input parameters applicable to the selected exposure scenario(s). When NORM or TENORM source terms are modeled, an additional understanding of the status of equilibrium, is necessary to accurately perform a dose assessment in support of dose based acceptance criteria. Historical information about the site processes/ores, selection of appropriate analytical analyses to identify key decay series radionuclide and a comprehensive review of the characterization data are needed to understand the equilibrium status of the decay series present. Once the source term has been characterized (in regards to relative activities of the radionuclides within a decay series) the source term must be input into RESRAD to reflect that status of equilibrium at time zero, or at the time since placement, if the characterization data reflects the equilibrium status of dated material. When the RESRAD output file is reviewed, depending on the time of maximum dose, DCGL values may be artificially high in value. Sum of fraction calculations, based on the status of equilibrium of each decay series, can also be used to assess the RESRAD results and develop an appropriate MARSSIM final status survey protocol. (authors)

  9. Addressing Naturally Occurring Asbestos in the Mining Industry

    NASA Astrophysics Data System (ADS)

    Bieber, D. W.

    2012-12-01

    Mining companies deal with naturally occurring asbestos (NOA) issues on their sites in two ways, avoidance and management. Avoidance simply means that to the extent practical, new mines are located in areas where NOA is unlikely to occur. Where mines are located in areas where NOA may be present, mines implement management procedures to identify and control potential sources of NOA. Management practices may include procedures set forth in regulations such as California's Air Toxicity Control Measure that deals with surface mining, voluntary procedures, or a combination of both. The mining industry generally recognizes that addressing NOA issues is a cost of doing business.;

  10. Arsenic poisoning in dairy cattle from naturally occurring arsenic pyrites.

    PubMed

    Hopkirk, R G

    1987-10-01

    An outbreak of arsenic poisoning occurred in which most of a 200 cow dairy herd were affected and six died. The source of the arsenic was naturally occurring arsenic pyrites from the Waiotapu Stream, near Rotorua. Arsenic levels in the nearby soil were as high as 6618 ppm. There was little evidence to suggest that treatment affected the course of the disease. Haematology was of little use in diagnosis, post-mortem signs were not always consistent and persistence of the element in the liver appeared short. Control of further outbreaks have been based on practical measures to minimise the intake of contaminated soil and free laying water by the stock. PMID:16031332

  11. Naturally occurring crystalline phases: analogues for radioactive waste forms

    SciTech Connect

    Haaker, R.F.; Ewing, R.C.

    1981-01-01

    Naturally occurring mineral analogues to crystalline phases that are constituents of crystalline radioactive waste forms provide a basis for comparison by which the long-term stability of these phases may be estimated. The crystal structures and the crystal chemistry of the following natural analogues are presented: baddeleyite, hematite, nepheline; pollucite, scheelite;sodalite, spinel, apatite, monazite, uraninite, hollandite-priderite, perovskite, and zirconolite. For each phase in geochemistry, occurrence, alteration and radiation effects are described. A selected bibliography for each phase is included.

  12. Synthetic muscle promoters: activities exceeding naturally occurring regulatory sequences

    NASA Technical Reports Server (NTRS)

    Li, X.; Eastman, E. M.; Schwartz, R. J.; Draghia-Akli, R.

    1999-01-01

    Relatively low levels of expression from naturally occurring promoters have limited the use of muscle as a gene therapy target. Myogenic restricted gene promoters display complex organization usually involving combinations of several myogenic regulatory elements. By random assembly of E-box, MEF-2, TEF-1, and SRE sites into synthetic promoter recombinant libraries, and screening of hundreds of individual clones for transcriptional activity in vitro and in vivo, several artificial promoters were isolated whose transcriptional potencies greatly exceed those of natural myogenic and viral gene promoters.

  13. An Update on Antitumor Activity of Naturally Occurring Chalcones

    PubMed Central

    Zhang, En-Hui; Wang, Ru-Feng; Guo, Shu-Zhen; Liu, Bin

    2013-01-01

    Chalcones, which have characteristic 1,3-diaryl-2-propen-1-one skeleton, are mainly produced in roots, rhizomes, heartwood, leaves, and seeds of genera Angelica, Sophora, Glycyrrhiza, Humulus, Scutellaria, Parartocarpus, Ficus, Dorstenia, Morus, Artocarpus, and so forth. They have become of interest in the research and development of natural antitumor agents over the past decades due to their broad range of mechanisms including anti-initiation, induction of apoptosis, antiproliferation, antimetastasis, antiangiogenesis, and so forth. This review summarizes the studies on the antitumor activity of naturally occurring chalcones and their underlying mechanisms in detail during the past decades. PMID:23690855

  14. Crystal structure of naturally occurring mercury(II) amidonitrate

    NASA Astrophysics Data System (ADS)

    Randall, Charles J.; Peacor, Donald R.; Rouse, Roland C.; Dunn, Pete J.

    1982-05-01

    A naturally-occurring mercuroammonium compound from Pitkin County, Colorado, is shown to be the natural analog of synthetic HgNH 2NO 3. The crystals are isometric, P4 132 or P4 332, with a = 10.254(1) and twelve formula weights per cell. Using 437 symmetry-independent reflections, the crystal structure was partially determined and refined to a residual of 0.090. The positions of the Hg atoms and the N and O atoms of the nitrate group were determined, but the amide ion could not be located, probably due to positional disorder. The structure contains mercury atoms arranged in equilateral triangles 3.421(1) on a side. These triangles are linked through shared vertices into helical chains wound around the fourfold screw axes. Similar triangular units occur in other inorganic Hg(II) compounds. The distortion of the nitrate ion from trigonal planar symmetry is also discussed.

  15. Naturally Occurring Animal Models with Outer Retina Phenotypes

    PubMed Central

    Baehr, Wolfgang; Frederick, Jeanne M.

    2009-01-01

    Naturally occurring and laboratory generated animal models serve as powerful tools with which to investigate the etiology of human retinal degenerations, especially retinitis pigmentosa (RP), Leber congenital amaurosis (LCA), cone dystrophies (CD) and macular degeneration (MD). Much progress has been made in elucidating gene defects underlying disease, in understanding mechanisms leading to disease, and in designing molecules for translational research and gene-based therapy to interfere with the progression of disease. Key to this progress has been study of naturally occurring murine and canine retinal degeneration mutants. This article will review the history, phenotypes and gene defects of select animal models with outer retina (photoreceptor and retinal pigment epithelium) degeneration phenotypes. PMID:19375447

  16. Diversified bioactivities of four types of naturally occurring quinochalcones.

    PubMed

    Zhao, Siyu; Lu, Xinmiao; Xiao, Cheng; Ning, Zhangchi; Zeng, Honglian; Ding, Xinzhe; Zhang, Yinhuan; Lu, Cheng; Liu, Yuanyan

    2014-12-01

    Quinochalcones, quinone-containing chalcones, belong to the flavonoid family and have attracted increasing popularity in Western countries in the last decade due to their pharmacological activities. This review describes four types of naturally occurring quinochalcones and summarizes their different pharmacological activities, including anti-cerebral ischemia, anti-tumor, and anti-infection activities. In addition, the pharmacological activities and relevant structure-activity relationships of synthetic quinochalcones are also reviewed. PMID:25172102

  17. Potentiating the naturally occurring process for repair of damaged heart.

    PubMed

    Li, Ming; Ng, Shi Chung

    2014-01-01

    This article reviews the current progresses in application of both exogenous and endogenous progenitor cells/stem cells for cardiac repair, and the current understanding of the naturally-occurring process for physiological myocyte turnover and possibly cardiac repair. In particular the development of methods for potentiating the naturally-occurring mechanism for substantial repair of pathologically damaged cardiac tissues is discussed. In the last decade, tremendous efforts to identify both exogenous and endogenous progenitor cells/stem cells possessing capacities of differentiating into cardiac lineages have been made for potential cardiac repair. Although many impressive progresses have been made in the application of differently sourced progenitor cells/stem cells, such as embryonic stem cells (ESCs), induced pluripotent stem cell (iPS), bone marrow-derived mesenchymal stem cells (MSCs), skeletal myoblasts (SMs), umbilical cord blood cells (UCBs), residential cardiac stem cells (CSCs), cardiac resident fibroblasts (CRFs), or adipose tissue-derived stem cells (ASCs) for repair of damaged heart, however, inevitable controversies exist concerning: (i) the immune compatibility of the exogenous donor progenitors/stem cells, (ii) the tumorigenicity with ESCs and iPS, and (iii) the efficiency of these exogenous or endogenous progenitors/ stem cells to acquire cardiac lineages to reconstitute the lost cardiac tissues. The recent recognition of some active small molecules that can induce myocardial regeneration to repair damaged heart tissues through enhancing the naturally-occurring cardiac-repair mechanism has offered the hope for clinical translation of the technology. Potentiating the naturally-occurring process for cardiac repair by administration of such small molecules has provided a promising strategy for reconstruction of damaged cardiac tissues after heart infarction. Therefore, this article is in favor of the notion that such small molecules with the activity of manipulating gene expressions in such a way of inducing endogenous stem cells to commit cardiac lineage differentiation and consequently myocardial regeneration may fulfill the dream of substantial repair of damaged heart. PMID:23844738

  18. Mineralogical Characteristics of Carbonate Rock-Hosted Naturally Occurring Asbestos

    NASA Astrophysics Data System (ADS)

    Shin, E.; Roh, Y.

    2012-12-01

    Naturally Occurring Asbestos (NOA) occurs in rocks and soils as a result of natural weathering and human activities. The parent rocks of asbestos have been associated with ultramafic and mafic rocks, and carbonate rock. The previous studies on naturally occurring asbestos were mainly limited to ultramafic and mafic rock-hosted asbestos and studies on carbonate rock-hosted asbestos are relatively rare in South Korea. Therefore, this study was aimed to characterize mineralogy of carbonate rock-hosted NOA at Muju and Jangsu, Jeonbuk province and Seosan and Asan, Chungnam province. The rock types at the four sites are consisting mainly of Precambrian metasedimentary rock. XRD and PLM analyses showed fibrous minerals in the sites were tremolite and actinolite of acicular and columnar forms. SEM-EDS analyses showed that asbestiform tremolite and actinolite had various ratios of length and diameters over 12:1, and needle and columnar forms. A columnar forms of tremolite and actinolite were showed small acicular at the edge of the particle. Its main chemical compositions are mainly Si, O, Mg, Ca, which were identical to tremolite. Actinolite contains Fe in addition to Si, O, Mg, Ca. EPMA analyses of asbestos occurred at Muju indicated that chemical composition are 55% SiO2, 23.2% MgO, 13.1 % CaO, and 0.61 % FeO and the chemical formula calculated as (K0.01Na0.01)Ca2.01(Mg4.94Fe0.05) (Al0.004Si7.98)O22(OH)2, which is close to ideal tremolite. In addition to tremolite, actinolite was also occurred at Seosan, Chungnam. XRD analyses showed that antigorite was existed at Muju, but PLM and SEM analyses showed the antigorite was platy structure, not asbestiform. These results indicate that asbestiform tremolite and actinolite with acicular forms contains in carbonate rocks at Muju and Jangsu, Jeonbuk and Seosan and Asan, Chungnam province South Korea.

  19. Naturally Occurring Anthraquinones: Chemistry and Therapeutic Potential in Autoimmune Diabetes

    PubMed Central

    Wu, Yueh-Chen

    2015-01-01

    Anthraquinones are a class of aromatic compounds with a 9,10-dioxoanthracene core. So far, 79 naturally occurring anthraquinones have been identified which include emodin, physcion, cascarin, catenarin, and rhein. A large body of literature has demonstrated that the naturally occurring anthraquinones possess a broad spectrum of bioactivities, such as cathartic, anticancer, anti-inflammatory, antimicrobial, diuretic, vasorelaxing, and phytoestrogen activities, suggesting their possible clinical application in many diseases. Despite the advances that have been made in understanding the chemistry and biology of the anthraquinones in recent years, research into their mechanisms of action and therapeutic potential in autoimmune disorders is still at an early stage. In this paper, we briefly introduce the etiology of autoimmune diabetes, an autoimmune disorder that affects as many as 10 million worldwide, and the role of chemotaxis in autoimmune diabetes. We then outline the chemical structure and biological properties of the naturally occurring anthraquinones and their derivatives with an emphasis on recent findings about their immune regulation. We discuss the structure and activity relationship, mode of action, and therapeutic potential of the anthraquinones in autoimmune diabetes, including a new strategy for the use of the anthraquinones in autoimmune diabetes. PMID:25866536

  20. Naturally occurring anthraquinones: chemistry and therapeutic potential in autoimmune diabetes.

    PubMed

    Chien, Shih-Chang; Wu, Yueh-Chen; Chen, Zeng-Weng; Yang, Wen-Chin

    2015-01-01

    Anthraquinones are a class of aromatic compounds with a 9,10-dioxoanthracene core. So far, 79 naturally occurring anthraquinones have been identified which include emodin, physcion, cascarin, catenarin, and rhein. A large body of literature has demonstrated that the naturally occurring anthraquinones possess a broad spectrum of bioactivities, such as cathartic, anticancer, anti-inflammatory, antimicrobial, diuretic, vasorelaxing, and phytoestrogen activities, suggesting their possible clinical application in many diseases. Despite the advances that have been made in understanding the chemistry and biology of the anthraquinones in recent years, research into their mechanisms of action and therapeutic potential in autoimmune disorders is still at an early stage. In this paper, we briefly introduce the etiology of autoimmune diabetes, an autoimmune disorder that affects as many as 10 million worldwide, and the role of chemotaxis in autoimmune diabetes. We then outline the chemical structure and biological properties of the naturally occurring anthraquinones and their derivatives with an emphasis on recent findings about their immune regulation. We discuss the structure and activity relationship, mode of action, and therapeutic potential of the anthraquinones in autoimmune diabetes, including a new strategy for the use of the anthraquinones in autoimmune diabetes. PMID:25866536

  1. Leaching Properties of Naturally Occurring Heavy Metals from Soils

    NASA Astrophysics Data System (ADS)

    Zhang, M.; Hoshino, M.; Yoshikawa, M.; Hara, J.; Sugita, H.

    2014-12-01

    The major threats to human health from heavy metals are associated with exposure to arsenic, lead, cadmium, chromium, mercury, as well as some other elements. The effects of such heavy metals on human health have been extensively studied and reviewed by international organizations such as WHO. Due to their toxicity, heavy metal contaminations have been regulated by national environmental standards in many countries, and/or laws such as the Soil Contamination Countermeasures Act in Japan. Leaching of naturally occurring heavy metals from the soils, especially those around abandoned metal mines into surrounding water systems, either groundwater or surface water systems, is one of the major pathways of exposure. Therefore, understanding the leaching properties of toxic heavy metals from naturally polluted soils is of fundamentally importance for effectively managing abandoned metal mines, excavated rocks discharged from infrastructure constructions such as tunneling, and/or selecting a pertinent countermeasure against pollution when it is necessary. In this study, soil samples taken from the surroundings of abandoned metal mines in different regions in Japan were collected and analyzed. The samples contained multiple heavy metals such as lead, arsenic and chromium. Standard leaching test and sequential leaching test considering different forms of contaminants, such as trivalent and pentavalent arsenics, and trivalent and hexavalent chromiums, together with standard test for evaluating total concentration, X-ray Fluorescence Analysis (XRF), X-ray diffraction analysis (XRD) and Cation Exchange Capacity (CEC) tests were performed. In addition, sequential leaching tests were performed to evaluate long-term leaching properties of lead from representative samples. This presentation introduces the details of the above experimental study, discusses the relationships among leaching properties and chemical and mineral compositions, indicates the difficulties associated with remediation of naturally polluted sites, and emphasizes the importance of risk-based countermeasures against naturally occurring heavy metals. Keywords: Leaching properties, Control Factor, Naturally Occurring Heavy Metals, Lead, Arsenic, Chromium

  2. Radiological protection in North American naturally occurring radioactive material industries.

    PubMed

    Chambers, D B

    2015-06-01

    All soils and rocks contain naturally occurring radioactive material (NORM). Many ores and raw materials contain relatively high levels of natural radionuclides, and processing such materials can further increase the concentrations of natural radionuclides, sometimes referred to as 'technologically enhanced naturally occurring radioactive material' (TENORM). Examples of NORM minerals include uranium ores, monazite (a source of rare earth minerals), and phosphate rock used to produce phosphate fertiliser. Such activities have the potential to result in above background radiation exposure to workers and the public. The objective of this paper is to review the sources and exposure from NORM in North American industries, and provide a perspective on the potential radiological hazards to workers and the environment. Proper consideration of NORM issues is important and needs to be integrated in the assessment of these projects. Concerns over radioactivity and radiation amongst non-governmental organisations and the local public have resulted in the cancellation of NORM mining and mineral extraction projects, as well as inhibition of the safe use of by-product materials from various NORM industries. This paper also briefly comments on the current regulatory framework for NORM (TENORM) in Canada and the USA, as well as the potential implications of the recent activities of the International Commission on Radiological Protection for NORM industries. PMID:25816274

  3. Active experiments, magnetospheric modification, and a naturally occurring analogue

    NASA Technical Reports Server (NTRS)

    Kivelson, M. G.; Russell, C. T.

    1973-01-01

    Recently, a scheme has been proposed which would modify the magnetosphere by injecting plasma near the equator beyond the plasmapause and initiating wave-particle instabilities. The expected effects have been examined theoretically. Injection of plasma into this region is also a naturally occurring phenomenon produced by the cross-tail electric fields which are associated with geomagnetic activity. For further investigation of magnetospheric instabilities, the advantages of examining artificially injected plasma (control of time and location of injection and of the volume of plasma injected) contrast with the advantages of studying natural enhancements (no extra payload, frequent occurrence). Thus, the two types of experiments are complementary. In preliminary studies of natural plasma enhancements both ULF and ELF emissions have been observed. The ELF noise is consistent with generation by the electron cyclotron instability.

  4. High naturally occurring radioactivity in fossil groundwater from the Middle East.

    PubMed

    Vengosh, Avner; Hirschfeld, Daniella; Vinson, David; Dwyer, Gary; Raanan, Hadas; Rimawi, Omar; Al-Zoubi, Abdallah; Akkawi, Emad; Marie, Amer; Haquin, Gustavo; Zaarur, Shikma; Ganor, Jiwchar

    2009-03-15

    High levels of naturally occurring and carcinogenic radium isotopes have been measured in low-saline and oxic groundwater from the Rum Group of the Disi sandstone aquifer in Jordan. The combined 228Ra and 226Ra activities are up to 2000% higher than international drinking water standards. Analyses of the host sandstone aquifer rocks show 228Ra and 226Ra activities and ratios that are consistent with previous reports of sandstone rocks from different parts of the world. A compilation of previous data in groundwater from worldwide sandstone aquifers shows large variations in Ra activities regardless of the groundwater salinity. On the basis of the distribution of the four Ra isotopes and the ratios of the short- to long-lived Ra isotopes, we postulate that Ra activity in groundwater is controlled by the balance of radioactive decay of parent Th isotopes on aquifer solids, decay of the dissolved radium isotopes, and adsorption of dissolved Ra on solid surfaces. The availability of surface adsorption sites, which depends on the clay content in the aquifer rocks, is therefore an important constraint for Ra activity in sandstone aquifers. These findings raise concerns about the safety of this and similar nonrenewable groundwater reservoirs, exacerbating the already severe water crisis in the Middle East. PMID:19368170

  5. Temporal Sequencing of Brain Activations During Naturally Occurring Thermoregulatory Events

    PubMed Central

    Diwadkar, Vaibhav A.; Murphy, Eric R.; Freedman, Robert R.

    2014-01-01

    Thermoregulatory events are associated with activity in the constituents of the spinothalamic tract. Whereas studies have assessed activity within constituents of this pathway, in vivo functional magnetic resonance imaging (fMRI) studies have not determined if neuronal activity in the constituents of the tract is temporally ordered. Ordered activity would be expected in naturally occurring thermal events, such as menopausal hot flashes (HFs), which occur in physiological sequence. The origins of HFs may lie in brainstem structures where neuronal activity may occur earlier than in interoceptive centers, such as the insula and the prefrontal cortex. To study such time ordering, we conducted blood oxygen level-dependent-based fMRI in a group of postmenopausal women to measure neuronal activity in the brainstem, insula, and prefrontal cortex around the onset of an HF (detected using synchronously acquired skin conductance responses). Rise in brainstem activity occurred before the detectable onset of an HF. Activity in the insular and prefrontal trailed that in the brainstem, appearing following the onset of the HF. Additional activations associated with HF's were observed in the anterior cingulate cortex and the basal ganglia. Pre-HF brainstem responses may reflect the functional origins of internal thermoregulatory events. By comparison insular, prefrontal and striatal activity may be associated with the phenomenological correlates of HFs. PMID:23787950

  6. Transmission of naturally occurring lymphoma in macaque monkeys.

    PubMed Central

    Hunt, R D; Blake, B J; Chalifoux, L V; Sehgal, P K; King, N W; Letvin, N L

    1983-01-01

    Spontaneously occurring rhesus monkey lymphomas were transmitted into healthy rhesus monkeys by using tumor cell suspensions. The naturally arising tumors included an immunoblastic sarcoma and an undifferentiated lymphoma. Recipient animals developed undifferentiated lymphomas, poorly differentiated lymphomas, or parenchymal lymphoproliferative abnormalities suggestive of early lesions of lymphoma. Some of these animals developed such opportunistic infections as cytomegalovirus hepatitis and cryptosporidiosis. They also showed evidence of an abnormal circulating peripheral blood mononuclear cell. These findings, all characteristic of the acquired immune deficiency syndrome (AIDS) of macaques, suggest a link between these transmissible lymphomas and AIDS in macaque monkeys. Images PMID:6576377

  7. Measurements for the Development of a Simulated Naturally Occurring Radioactive Material

    PubMed Central

    Pibida, L.

    2012-01-01

    Nineteen different commercially available samples containing naturally occurring radioactive materials (NORM) (i.e., natural uranium, thorium, radium and potassium) were investigated, including zircon sand, cat litter, roofing tiles, ice melt and fertilizer among others. A large variation in isotopic composition was observed across the measured samples. As a result of this observation, a need was identified to develop and implement the use of a simulated NORM sample to serve as a reference standard sample containing naturally occurring radioactive elements. The purpose of the simulated NORM sample would be to simulate typical samples containing NORM to be used for testing radiation detection instruments against ANSI/IEEE and IEC document standards requirements. The design and construction of the proposed new simulated NORM sample and the subsequent energy spectra characterization measurements are presented as part of this work. PMID:26900520

  8. Trapezoidal keratotomy for the correction of naturally occurring astigmatism.

    PubMed

    Ibrahim, O; Hussein, H A; el-Sahn, M F; el-Nawawy, S; Kassem, A; Waring, G O

    1991-10-01

    We performed trapezoidal keratotomy, consisting of combined nonintersecting semiradial and transverse incisions, in 64 eyes of 45 consecutive patients with naturally occurring astigmatism. The central clear zone diameter and number and length of transverse incisions were determined by the refractive error. Mean preoperative refractive astigmatism was 3.18 +/- 1.16 diopters (D) (range, 2.25 to 7.00 D). At the 1-year follow-up examination, the mean surgically corrected astigmatism determined by vector analysis was 3.70 +/- 1.50 D (range, 0.75 to 8.5 D), and the mean residual refractive astigmatism was 0.85 +/- 0.72 D (range, 0 to 4.0 D), with 64% of eyes having 1.00 D or less. The smaller the clear zone diameter, the greater the astigmatic correction. Longer transverse incisions produced more steepening of the secondary meridian. The operative complications included microperforation (5%), misalignment of surgical meridian (6%), encroachment on clear zone (5%), and inadvertent crossed incisions (11%). Trapezoidal keratotomy reduced naturally occurring astigmatism, but with only fair predictability and with some irregular astigmatism due to irregular wound healing. PMID:1929924

  9. Regulation of naturally occurring radioactive materials in Australia.

    PubMed

    Jeffries, Cameron; Akber, Riaz; Johnston, Andrew; Cassels, Brad

    2011-07-01

    In order to promote uniformity between jurisdictions, the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) has developed the National Directory for Radiation Protection, which is a regulatory framework that all Australian governments have agreed to adopt. There is a large and diverse range of industries involved in mining or mineral processing, and the production of fossil fuels in Australia. Enhanced levels of naturally occurring radionuclides can be associated with mineral extraction and processing, other industries (e.g. metal recycling) and some products (e.g. plasterboard). ARPANSA, in conjunction with industry and State regulators, has undertaken a review and assessment of naturally occurring radioactive material (NORM) management in Australian industries. This review has resulted in guidance on the management of NORM that will be included in the National Directory for Radiation Protection. The first NORM safety guide provides the framework for NORM management and addresses specific NORM issues in oil and gas production, bauxite, aluminium and phosphate industries. Over time further guidance material for other NORM-related industries will be developed. This presentation will provide an overview of the regulatory approach to managing NORM industries in Australia. PMID:21515621

  10. Macaques Exhibit a Naturally-Occurring Depression Similar to Humans

    PubMed Central

    Xu, Fan; Wu, Qingyuan; Xie, Liang; Gong, Wei; Zhang, Jianguo; Zheng, Peng; Zhou, Qinmin; Ji, Yongjia; Wang, Tao; Li, Xin; Fang, Liang; Li, Qi; Yang, Deyu; Li, Juan; Melgiri, Narayan D.; Shively, Carol; Xie, Peng

    2015-01-01

    Rodent models have dominated preclinical investigations into the mechanisms of depression. However, these models-which rely on subjecting individual rodents to physical stressors - do not realistically resemble the etiopathological development of depression, which occurs naturally in a social context. A non-human primate model that better reflects the social ethological aspects of depression would be more advantageous to investigating pathophysiological mechanisms and developing antidepressant therapeutics. Here, we describe and model a naturally-occurring depressive state in a non-human primate species, the cynomolgus monkey (Macaca fascicularis), in a realistic social ethological context and associate the depressed behavioral phenotype with significant serum metabolic perturbations. One to two subjects per stable social colony (17–22 subjects) manifested a depressive phenotype that may be attributed to psychosocial stress. In accordance with rodent and human studies, the serum metabolic phenotype of depressed and healthy subjects significantly differed, supporting the model's face validity. However, application of the fast-acting antidepressant ketamine failed to demonstrate predictive validity. This study proposes a non-human primate depression model in a realistic social ethological context that can better approximate the psychosocial stressors underlying depression. PMID:25783476

  11. Beauveria caledonica is a naturally occurring pathogen of forest beetles.

    PubMed

    Glare, Travis R; Reay, Stephen D; Nelson, Tracey L; Moore, Roger

    2008-03-01

    In New Zealand, two introduced scolytid beetles, Hylastes ater and Hylurgus ligniperda (Curculionidae: Scolytinae) are pests in pine plantations. Investigation of the naturally occurring pathogens of these exotic pests revealed that both are attacked by Beauveria caledonica, a species originally isolated and described from soil in Scotland. The isolates in New Zealand were identical in morphology and conserved DNA region (rDNA, elongation factor alpha) sequence to isolates held in the USDA-ARS insect pathogens culture collection. In bioassay, the B. caledonica isolates were highly pathogenic to adults of H. ligniperda and larvae of Tenebrio molitor. Sporulation was observed on cadavers, confirming the species can utilise the cadavers. As both species were likely to have been introduced to New Zealand from Europe, a search was made for B. caledonica in the northern UK and Ireland. The fungus was found as a naturally-occurring pathogen of the weevil pest, Hylobius abietis (Curculionidae: Scolytinae), developing in spruce and other beetles in forests in both regions. PMID:18308525

  12. Naturally Occurring Animal Models of Human Hepatitis E Virus Infection

    PubMed Central

    Yugo, Danielle M.; Cossaboom, Caitlin M.; Meng, Xiang-Jin

    2014-01-01

    Hepatitis E virus (HEV) is a single-stranded, positive-sense RNA virus in the family Hepeviridae. Hepatitis E caused by HEV is a clinically important global disease. There are currently four well-characterized genotypes of HEV in mammalian species, although numerous novel strains of HEV likely belonging to either new genotypes or species have recently been identified from several other animal species. HEV genotypes 1 and 2 are limited to infection in humans, whereas genotypes 3 and 4 infect an expanding host range of animal species and are zoonotic to humans. Historical animal models include various species of nonhuman primates, which have been indispensable for the discovery of human HEV and for understanding its pathogenesis and course of infection. With the genetic identification and characterization of animal strains of HEV, a number of naturally occurring animal models such as swine, chicken, and rabbit have recently been developed for various aspects of HEV research, including vaccine trials, pathogenicity, cross-species infection, mechanism of virus replication, and molecular biology studies. Unfortunately, the current available animal models for HEV are still inadequate for certain aspects of HEV research. For instance, an animal model is still lacking to study the underlying mechanism of severe and fulminant hepatitis E during pregnancy. Also, an animal model that can mimic chronic HEV infection is critically needed to study the mechanism leading to chronicity in immunocompromised individuals. Genetic identification of additional novel animal strains of HEV may lead to the development of better naturally occurring animal models for HEV. This article reviews the current understanding of animal models of HEV infection in both natural and experimental infection settings and identifies key research needs and limitations. PMID:24936039

  13. Antiparasitic properties of medicinal plants and other naturally occurring products.

    PubMed

    Tagboto, S; Townson, S

    2001-01-01

    Parasitic diseases remain a major public health problem affecting hundreds of millions of people, particularly in tropical developing countries. The limited availability and affordability of pharmaceutical medicines means that the majority of the world's population depends on traditional medical remedies, and it is estimated that some 20,000 species of higher plant are used medicinally throughout the world. Many well-known drugs listed in the modern pharmacopoeia have their origins in nature, including, for example, quinine from the bark of the Cinchona tree for the treatment of malaria, which has been followed by the subsequent development of the synthetic derivatives chloroquine, amodiaquine, primaquine and mefloquine. More recently, the wider recognition of the antimalarial activity of artemisinin from the herb Artemisia annua has led current research to focus on the development of a large number of synthetic and semisynthetic compounds, which are more active than artemisinin. There is an increasing awareness of the potential of natural products, which may lead to the development of much-needed new antiparasitic drugs. In this chapter, we have drawn together a comprehensive list of medicinal plants and other natural products that have been shown to have activity against human and, to a lesser extent, animal parasites. In addition, some of the opportunities and difficulties in working with natural products have been reviewed and discussed, including the problems involved with evaluating complex mixtures of compounds which may occur in extracts, problems associated with differentiating between general cytotoxicity and genuine antiparasitic activity, and the hope that new technologies will rapidly accelerate new drug discovery and development in this field. Nevertheless, the way forward for natural product medicines, including the conservation of recognized natural products and protection of general biodiversity, the discovery and development process, and the promotion and usage of existing remedies, presents some difficult challenges. Following an initiative by the World Health Organization in August 2000, there is now the opportunity to evaluate scientifically many more traditional medicines and other natural products in validated antiparasite and toxicity screens, which will help establish which substances have potential for new pharmaceutical products. The use of 'untested' traditional medicines will no doubt continue, and there is an urgent need to distinguish between the efficacious and safe products and the ineffective and/or unsafe products, particularly since many remedies are being more widely promoted in developing countries. PMID:11757332

  14. Metabolic mechanism of phenyllactic acid naturally occurring in Chinese pickles.

    PubMed

    Li, Xingfeng; Ning, Yawei; Liu, Dou; Yan, Aihong; Wang, Zhixin; Wang, Shijie; Miao, Ming; Zhu, Hong; Jia, Yingmin

    2015-11-01

    Phenyllactic acid, a phenolic acid phytochemical with the antimicrobial activity, was rarely reported in food besides honey and sourdough. This study evidenced a new food source of phenyllactic acid and elucidated its metabolic mechanism. Phenyllactic acid naturally occurred in Chinese pickles with concentrations ranged from 0.02 to 0.30 mM in 23 pickle samples including homemade and commercial ones. Then, lactic acid bacteria capable of metabolizing phenyllactic acid were screened from each homemade pickle and a promising strain was characterized as Lactobacillus plantarum. Moreover, the investigation of the metabolic mechanism of phenyllactic acid in pickles suggested that the yield of phenyllactic acid was positively related to the content of phenylalanine in food, and the addition of phenylalanine as precursor substance could significantly promote the production of phenyllactic acid. This investigation could provide some insights into the accumulation of phenyllactic acid in pickle for long storage life. PMID:25976820

  15. Is anyone regulating naturally occurring radioactive material? A state survey

    SciTech Connect

    Gross, E.M.; Barisas, S.G.

    1993-08-01

    As far as we know, naturally occurring radioactive material (NORM) has surrounded humankind since the beginning of time. However, recent data demonstrating that certain activities concentrate NORM have increased concern regarding its proper handling and disposal and precipitated the development of new NORM-related regulations. The regulation of NORM affects the management of government facilities as well as a broad range of industrial processes. Recognizing that NORM regulation at the federal level is extremely limited, Argonne National Laboratory (ANL) conducted a 50-state survey to determine the extent to which states have assumed the responsibility for regulating NORM as well as the NORM standards that are currently being applied at the state level. Though the survey indicates that NORM regulation comprises a broad spectrum of controls from full licensing requirements to virtually no regulation at afl, a trend is emerging toward recognition of the need for increased regulation of potential NORM hazards, particularly in the absence of federal standards.

  16. Neuropathology of naturally occurring Trypanosoma evansi infection of horses.

    PubMed

    Rodrigues, A; Fighera, R A; Souza, T M; Schild, A L; Barros, C S L

    2009-03-01

    The clinical signs and pathology of the central nervous system in 9 horses with naturally occurring neurologic disease due to Trypanosoma evansi are described. The clinical course was 2 to 20 days; clinical signs included marked ataxia, blindness, head tilt and circling, hyperexcitability, obtundity, proprioceptive deficits, head pressing, and paddling movements. Grossly, asymmetric leukoencephalomalacia with yellowish discoloration of white matter and flattening of the gyri were observed in the brain of 7 of 9 horses. Histologically, all 9 horses had necrotizing encephalitis that was most severe in the white matter, with edema, demyelination, and lymphoplasmacytic perivascular cuffs. Mild to moderate meningitis or meningomyelitis was observed in the spinal cord of 5 of 7 horses. T. evansi was detected immunohistochemically in the perivascular spaces and neuropil of formalin-fixed, paraffin-embedded brain tissue in 8 of 9 horses. PMID:19261636

  17. Management of Naturally Occurring Radioactive Materials (NORM) in Canada

    NASA Astrophysics Data System (ADS)

    Baweja, Anar S.; Tracy, Bliss L.

    2008-08-01

    In Canada, nuclear and radiological regulatory responsibilities are shared between the provinces/territories and the federal government. The Canadian Nuclear Safety Commission (CNSC) regulates nuclear fuel cycle materials and man-made radionuclides under the Nuclear Safety and Control Act (2000). The provinces and territories regulate NORM arising from industrial activities, not involving the nuclear fuel cycle materials. Present guidelineCanadian Guidelines for the Management of Naturally Occurring Radioactive Materials (NORM)was published in 2000 in order to bring uniformity to the management of NORM-related procedures to provide adequate radiation protection for workers and the general public. The basic premise of these guidelines is that the NORM-related activities should not be posing any greater hazard than those activities regulated under the Nuclear Safety and Control Act; these concepts are described in this paper.

  18. Cytotoxicity and superoxide anion generation by some naturally occurring quinones.

    PubMed

    Johnson Inbaraj, J; Gandhidasan, R; Murugesan, R

    1999-05-01

    Four naturally occurring quinones, mansonone-D (MD), mansonone-H (MH), thespone (TP) and thespesone (TPE), extracted from the heartwood of Thespesia populnea have been tested for their cytotoxic action by aerobic incubation with human breast adenocarcinoma (MCF-7) cells. Toxicity of the quinones follows the order MD > TP > MH approximately TPE. EPR spectrometric and Clark electrode oximetric studies indicate that redox cycling of these quinones produce superoxide anion radical (O2*-) and H2O2 on aerobic incubation with NADH:cytochrome c reductase. Generation of superoxide radical during enzymatic reduction of quinones, was confirmed by EPR spin trapping experiment using 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) as a spin trap. Cyclic voltammetric studies show reversible redox couples for MD and TP whereas TPE and MH show irreversible redox couple. The electrochemical results indicate that MH and TPE are more difficult to reduce than TP and MD. PMID:10381175

  19. Naturally Occurring Peptides from Rana temporaria: Antimicrobial Properties and More.

    PubMed

    Mangoni, Maria Luisa; Grazia, Antonio Di; Cappiello, Floriana; Casciaro, Bruno; Luca, Vincenzo

    2016-01-01

    The extensive search for alternative therapeutics against microbial pathogens has led to the discovery of cationic peptides as new anti-infectives with a novel mode of action. Particular interest has been devoted to small linear peptides that can be efficiently made by chemical synthesis at competitive costs. The most promising originate from a large family of short, naturally occurring peptides found in the skin of amphibia of Rana genus, i.e. the temporins. This review is mainly focused on the recent structure-function studies of the earliest known temporin isoforms (TA, TB and TL) and their potential clinical role as novel antimicrobial agents. The development of novel antibiotics is an urgent public health concern due to the increased resistance of microorganisms to conventional antibiotics, particularly in the hospital setting. PMID:26139114

  20. Additive CHARMM force field for naturally occurring modified ribonucleotides.

    PubMed

    Xu, You; Vanommeslaeghe, Kenno; Aleksandrov, Alexey; MacKerell, Alexander D; Nilsson, Lennart

    2016-04-15

    More than 100 naturally occurring modified nucleotides have been found in RNA molecules, in particular in tRNAs. We have determined molecular mechanics force field parameters compatible with the CHARMM36 all-atom additive force field for all these modifications using the CHARMM force field parametrization strategy. Emphasis was placed on fine tuning of the partial atomic charges and torsion angle parameters. Quantum mechanics calculations on model compounds provided the initial set of target data, and extensive molecular dynamics simulations of nucleotides and oligonucleotides in aqueous solutions were used for further refinement against experimental data. The presented parameters will allow for computational studies of a wide range of RNAs containing modified nucleotides, including the ribosome and transfer RNAs. © 2016 The Authors. Journal of Computational Chemistry Published by Wiley Periodicals, Inc. PMID:26841080

  1. Epigenetic Variation in Mangrove Plants Occurring in Contrasting Natural Environment

    PubMed Central

    Lira-Medeiros, Catarina Fonseca; Parisod, Christian; Fernandes, Ricardo Avancini; Mata, Camila Souza; Cardoso, Monica Aires; Ferreira, Paulo Cavalcanti Gomes

    2010-01-01

    Background Epigenetic modifications, such as cytosine methylation, are inherited in plant species and may occur in response to biotic or abiotic stress, affecting gene expression without changing genome sequence. Laguncularia racemosa, a mangrove species, occurs in naturally contrasting habitats where it is subjected daily to salinity and nutrient variations leading to morphological differences. This work aims at unraveling how CpG-methylation variation is distributed among individuals from two nearby habitats, at a riverside (RS) or near a salt marsh (SM), with different environmental pressures and how this variation is correlated with the observed morphological variation. Principal Findings Significant differences were observed in morphological traits such as tree height, tree diameter, leaf width and leaf area between plants from RS and SM locations, resulting in smaller plants and smaller leaf size in SM plants. Methyl-Sensitive Amplified Polymorphism (MSAP) was used to assess genetic and epigenetic (CpG-methylation) variation in L. racemosa genomes from these populations. SM plants were hypomethylated (14.6% of loci had methylated samples) in comparison to RS (32.1% of loci had methylated samples). Within-population diversity was significantly greater for epigenetic than genetic data in both locations, but SM also had less epigenetic diversity than RS. Frequency-based (GST) and multivariate (?ST) methods that estimate population structure showed significantly greater differentiation among locations for epigenetic than genetic data. Co-Inertia analysis, exploring jointly the genetic and epigenetic data, showed that individuals with similar genetic profiles presented divergent epigenetic profiles that were characteristic of the population in a particular environment, suggesting that CpG-methylation changes may be associated with environmental heterogeneity. Conclusions In spite of significant morphological dissimilarities, individuals of L. racemosa from salt marsh and riverside presented little genetic but abundant DNA methylation differentiation, suggesting that epigenetic variation in natural plant populations has an important role in helping individuals to cope with different environments. PMID:20436669

  2. Multifaceted ability of naturally occurring polyphenols against metastatic cancer.

    PubMed

    Zhou, Qingyu; Bennett, Lunawati L; Zhou, Shufeng

    2016-04-01

    Although cancer metastases are known to be the main cause of cancer-related deaths, truly effective antimetastatic therapeutics remain scarce in clinical practice. Naturally occurring polyphenols are the most abundant antioxidants in human diets. Many of them possess chemopreventive and chemotherapeutic properties against various types of cancer. Recent advances in understanding the molecular pathways that mediate cancer development and progression have led to an increase of interest in preclinical investigations on the mechanisms underlying anticancer activity of polyphenols. In particular, an increasing number of preclinical studies using cultured cells and animal models have demonstrated the inhibitory effects of polyphenols on tumour cell invasion and metastasis, thereby highlighting the potential of polyphenols against metastatic cancer. This review specifically addresses growing evidence of the capability of polyphenols to impair the invasion and migration of tumour cells through a diverse set of mechanisms, including downregulation of expression of matrix metalloproteinases, modulation of regulators of epithelial-mesenchymal transition, interference with Met signalling, inhibition of nuclear factor-kappa B mediated transcription, and so on. Given that metastasis occurs through a multistep process in which each step is regulated by a complex network of signalling pathways, the multi-function and multi-target characteristics of polyphenols render those promising candidates for effective adjuvant therapy against metastatic cancer. PMID:26773801

  3. Canine osteosarcoma: a naturally occurring disease to inform pediatric oncology.

    PubMed

    Fenger, Joelle M; London, Cheryl A; Kisseberth, William C

    2014-01-01

    Osteosarcoma (OSA) is the most common form of malignant bone cancer in children and dogs, although the disease occurs in dogs approximately 10 times more frequently than in people. Multidrug chemotherapy and aggressive surgical techniques have improved survival; however, new therapies for OSA are critical, as little improvement in survival times has been achieved in either dogs or people over the past 15 years, even with significant efforts directed at the incorporation of novel therapeutic approaches. Both clinical and molecular evidence suggests that human and canine OSA share many key features, including tumor location, presence of microscopic metastatic disease at diagnosis, development of chemotherapy-resistant metastases, and altered expression/activation of several proteins (e.g. Met, ezrin, phosphatase and tensin homolog, signal transducer and activator of transcription 3), and p53 mutations, among others. Additionally, canine and pediatric OSA exhibit overlapping transcriptional profiles and shared DNA copy number aberrations, supporting the notion that these diseases are similar at the molecular level. This review will discuss the similarities between pediatric and canine OSA with regard to histology, biologic behavior, and molecular genetic alterations that indicate canine OSA is a relevant, spontaneous, large animal model of the pediatric disease and outline how the study of naturally occurring OSA in dogs will offer additional insights into the biology and future treatment of this disease in both children and dogs. PMID:24936031

  4. Inhibition of carcinogenesis by naturally-occurring and synthetic compounds.

    PubMed

    Wattenberg, L W

    1990-01-01

    A continuing study of chemopreventive agents has focused on three categories of naturally-occurring compounds that inhibit carcinogen activation and are effective in preventing carcinogen-induced neoplasia when administered at short time intervals prior to carcinogen challenge. The three are: aromatic isothiocyanates found in cruciferous vegetables, monoterpenes from citrus fruits and caraway seed oils, and organosulfur compounds occurring in Allium species. The short time-interval effects could be significant in terms of their impact on responses of humans to carcinogen exposures. The capacity of sodium cyanate, cruciferous vegetables, orange oil, benzyl isothiocyanate, and D-limonene to act as both blocking and suppressing agents has been discussed. Two possible mechanisms for this multiphase activity were presented. The first is that these inhibitory substances activate a complex integrated defense mechanism against toxic compounds which entails both blocking and suppressing components. The blocking component is the initial line of defense, and the suppressing component constitutes a "fail-safe" backup to assure that if any of the toxic material attacks cellular constituents, its effects will be nullified. The second possible mechanism considered is that the inhibitors, because of high reactivity, have multiple biological effects that are separate and not part of a single, coordinated response. Inhibitors that have both blocking and suppressing effects could be particularly useful as chemopreventive agents. PMID:2183767

  5. Fenugreek: a naturally occurring edible spice as an anticancer agent

    PubMed Central

    Shabbeer, Shabana; Sobolewski, Michelle; Kachhap, Sushant; Davidson, Nancy; Carducci, Michael A.; Khan, Saeed

    2011-01-01

    In recent years, various dietary components that can potentially be used for the prevention and treatment of cancer have been identified. In this study, we demonstrate that extract (FE) from the seeds of the plant Trigonella foenum graecum, commonly called fenugreek, are cytotoxic in vitro to a panel of cancer but not normal cells. Treatment with 10-15 ug/mL of FE for 72h was growth inhibitory to breast, pancreatic and prostate cancer cell lines (PCa). When tested at higher doses (15-20 ug/mL), FE continued to be growth inhibitory to PCa cell lines but not to either primary prostate or htert-immortalized prostate cells. At least part of the growth inhibition is due to induction of cell death, as seen by incorporation of Ethidium Bromide III into cancer cells exposed to FE. Molecular changes induced in PCa cells are: in DU-145 cells: down regulation of mutant p53, and in PC-3 cells up regulation of p21 and inhibition of TGF-? induced phosphorylation of Akt. The surprising finding of our studies is that death of cancer cells occurs despite growth stimulatory pathways being simultaneously up regulated (phosphorylated) by FE. Thus, these studies add another biologically active agent to our armamentarium of naturally occurring agents with therapeutic potential. PMID:19197146

  6. Sequestering Naturally Occurring Liquid Carbon Dioxide in the Deep Ocean

    NASA Astrophysics Data System (ADS)

    Capron, M. E.

    2008-12-01

    Liquid carbon dioxide has been found as shallow as 1,500 meters in seafloor ooze. Did the liquid carbon dioxide originate from volcanic activity? Or did bacteria convert organic matter, which started as atmospheric carbon dioxide, into methane and liquid carbon dioxide? At typical ocean temperatures carbon dioxide coming out of solution below 600 meters will be liquid. Therefore, one likely mechanism for generating liquid carbon dioxide in seafloor ooze is the bacterial decomposition of organic matter. This paper examines quantitative and qualitative bacterial decomposition of aquatic biomass, with an emphasis on assessing and demonstrating feasibility. Calculations suggest natural processes sequestering liquid carbon dioxide in the seafloor can be sustainably increased to decrease atmospheric carbon dioxide concentrations. First, algae growing on the ocean surface absorb carbon dioxide. The algae are then gathered into a submerged container. Naturally occurring bacteria will digest the algae producing methane, liquid carbon dioxide, and ammonium. The ammonium can be recycled as a nutrient for growing more algae. Bacterial decomposition continues in dilute solutions with any biomass. The process does not require any particular biomass. Also, concentrating the biomass by removing water is not essential. The buoyancy provided by water allows relatively inexpensive tension fabric structures to contain the dilute algae and decomposition products. Calculations based on algae growth in open ponds and experience with bacterial decomposition at 1 to 5 bar pressures suggest the economics of the associated macro-algae growing and harvesting can favor increasing ocean species diversity.

  7. Helium isotopic abundance variation in nature

    SciTech Connect

    Holden, N.E.

    1993-08-01

    The isotopic abundance of helium in nature has been reviewed. This atomic weight value is based on the value of helium in the atmosphere, which is invariant around the world and up to a distance of 100,000 feet. Helium does vary in natural gas, volcanic rocks and gases, ocean floor sediments, waters of various types and in radioactive minerals and ores due to {alpha} particle decay of radioactive nuclides.

  8. Forecasting Seizures in Dogs with Naturally Occurring Epilepsy

    PubMed Central

    Stead, S. Matt; Brinkmann, Ben; Vasoli, Vincent; Crepeau, Daniel; Vite, Charles H.; Sturges, Beverly; Ruedebusch, Vanessa; Mavoori, Jaideep; Leyde, Kent; Sheffield, W. Douglas; Litt, Brian; Worrell, Gregory A.

    2014-01-01

    Seizure forecasting has the potential to create new therapeutic strategies for epilepsy, such as providing patient warnings and delivering preemptive therapy. Progress on seizure forecasting, however, has been hindered by lack of sufficient data to rigorously evaluate the hypothesis that seizures are preceded by physiological changes, and are not simply random events. We investigated seizure forecasting in three dogs with naturally occurring focal epilepsy implanted with a device recording continuous intracranial EEG (iEEG). The iEEG spectral power in six frequency bands: delta (0.14 Hz), theta (48 Hz), alpha (812 Hz), beta (1230 Hz), low-gamma (3070 Hz), and high-gamma (70180 Hz), were used as features. Logistic regression classifiers were trained to discriminate labeled pre-ictal and inter-ictal data segments using combinations of the band spectral power features. Performance was assessed on separate test data sets via 10-fold cross-validation. A total of 125 spontaneous seizures were detected in continuous iEEG recordings spanning 6.5 to 15 months from 3 dogs. When considering all seizures, the seizure forecasting algorithm performed significantly better than a Poisson-model chance predictor constrained to have the same time in warning for all 3 dogs over a range of total warning times. Seizure clusters were observed in all 3 dogs, and when the effect of seizure clusters was decreased by considering the subset of seizures separated by at least 4 hours, the forecasting performance remained better than chance for a subset of algorithm parameters. These results demonstrate that seizures in canine epilepsy are not randomly occurring events, and highlight the feasibility of long-term seizure forecasting using iEEG monitoring. PMID:24416133

  9. Naturally occurring mastitis disrupts developmental competence of bovine oocytes.

    PubMed

    Roth, Z; Dvir, A; Kalo, D; Lavon, Y; Krifucks, O; Wolfenson, D; Leitner, G

    2013-10-01

    We examined the effects of naturally occurring mastitis on bovine oocyte developmental competence in vitro. Specifically, we investigated the effects of intramammary infection on the ovarian pool of oocytes (i.e., follicle-enclosed oocytes) and their ability to undergo in vitro maturation, fertilization, and further development to the blastocyst stage. Culled Holstein cows (n=50) from 9 commercial dairy farms in Israel were allotted to 3 groups according to somatic cell count (SCC) records of the last 3 monthly milk tests as well as of quarter samples collected before slaughter: (1) low SCC (n=7), (2) medium SCC (n=16), or (3) high SCC (n=27). Means of SCC values differed among low-, medium-, and high-SCC groups: 148,000, 311,000 and 1,813,000 cell/mL milk, respectively. Milk yield and days in milk did not differ among the 3 groups. Bacterial isolates included coagulase-negative staphylococci, Escherichia coli, Streptococcus dysgalactiae, or no bacteria found. Ovaries were collected at the abattoir and brought to the laboratory. Cumulus oocyte complexes were recovered separately from each cow and subjected individually to in vitro maturation and fertilization, followed by 8d in culture. The number of aspirated oocytes did not differ among groups, with a range of 17 to 21 oocytes per cow. The proportion of oocytes that cleaved into 2- to 4-cell-stage embryos (86.1 ± 3.4%) did not differ among groups. In contrast, mean percentages of embryos developed to the blastocyst stage on d 7 and 8 after fertilization were less in both medium- and-high SCC groups than in the low-SCC group (5.6 ± 2.3 and 4.1 ± 1.8 vs. 18.1 ± 4.6%, respectively). Additional analysis indicated that cleavage and blastocyst-formation rates did not differ among the bacterial types in the low-, medium-, and high-SCC groups. These are the first results to demonstrate that naturally occurring mastitis disrupts the developmental competence of the ovarian pool of oocytes, (i.e., oocytes at the germinal vesicle stage). The disruption was associated with elevation of SCC rather than bacterial type. The results may provide a partial explanation for the low fertility of cows that have contracted mastitic pathogens before insemination. PMID:23957998

  10. Naturally occurring phytochemicals for the prevention of Alzheimer's disease.

    PubMed

    Kim, Jiyoung; Lee, Hyong Joo; Lee, Ki Won

    2010-03-01

    Alzheimer's disease (AD) is an age-related neurodegenerative disease increasingly recognized as one of the most important medical problems affecting the elderly. Although a number of drugs, including several cholinesterase inhibitors and an NMDA receptor antagonist, have been approved for use, they have been shown to produce diverse side effects and yield relatively modest benefits. To overcome these limitations of current therapeutics for AD, extensive research and development are underway to identify drugs that are effective and free of undesirable side effects. Certain naturally occurring dietary polyphenolic phytochemicals have received considerable recent attention as alternative candidates for AD therapy. In particular, curcumin, resveratrol, and green tea catechins have been suggested to have the potential to prevent AD because of their anti-amyloidogenic, anti-oxidative, and anti-inflammatory properties. These polyphenolic phytochemicals also activate adaptive cellular stress responses, called 'neurohormesis', and suppress disease processes. In this commentary, we describe the amyloid-beta-induced pathogenesis of AD, and summarize the intracellular and molecular targets of selected dietary phytochemicals that might slow the progression of AD. PMID:20050972

  11. Identifying Naturally Occurring Retirement Communities: A Spatial Analysis

    PubMed Central

    Rivera-Hernandez, Maricruz; Yamashita, Takashi; Kinney, Jennifer M.

    2016-01-01

    Objectives Guided by the concept of “aging in place” and potential policy implications, the study analyzed naturally occurring retirement communities (NORCs; 40% or greater house owners and renters aged 65 years and older) and whether there were spatiotemporal patterns in Ohio between 2000 and 2010. Method Data were derived from the 2000 and 2010 census tracts. Geovisualization was used to visually examine the distribution of NORCs in 2000 and 2010. Global Moran’s I was used to quantify the spatial distribution of NORCs in Ohio and Local Moran’s I was used to identify clusters of NORCs (i.e., hot spots). Results The number of NORCs slightly decreased despite the overall increase of the older population from 2000 to 2010. NORCs were identified in one of the 3 most populous counties (i.e., Cuyahoga) and its neighboring counties. A number of hot spots were identified in Cuyahoga County (among Ohio’s most populous and NORC-rich counties), both in 2000 and 2010. There were different patterns including emerging, disappearing, and enduring NORCs and disproportionate distributions of NORCs across the state between 2000 and 2010. Discussion Locating NORCs could aid governments to create “aging in place” sensitive policies to address issues of independence, social care, health care, volunteerism, and community participation. PMID:24958694

  12. Design of Bioactive Peptides from Naturally Occurring ?-Conotoxin Structures*

    PubMed Central

    Stevens, Marijke; Peigneur, Steve; Dyubankova, Natalia; Lescrinier, Eveline; Herdewijn, Piet; Tytgat, Jan

    2012-01-01

    To date, cone snail toxins (conotoxins) are of great interest in the pursuit of novel subtype-selective modulators of voltage-gated sodium channels (Navs). Navs participate in a wide range of electrophysiological processes. Consequently, their malfunctioning has been associated with numerous diseases. The development of subtype-selective modulators of Navs remains highly important in the treatment of such disorders. In current research, a series of novel, synthetic, and bioactive compounds were designed based on two naturally occurring ?-conotoxins that target Navs. The initial designed peptide contains solely 13 amino acids and was therefore named Mini peptide. It was derived from the ?-conotoxins KIIIA and BuIIIC. Based on this Mini peptide, 10 analogues were subsequently developed, comprising 1216 amino acids with two disulfide bridges. Following appropriate folding and mass verification, blocking effects on Navs were investigated. The most promising compound established an IC50 of 34.1 0.01 nm (R2-Midi on Nav1.2). An NMR structure of one of our most promising compounds was determined. Surprisingly, this structure does not reveal an ?-helix. We prove that it is possible to design small peptides based on known pharmacophores of ?-conotoxins without losing their potency and selectivity. These data can provide crucial material for further development of conotoxin-based therapeutics. PMID:22773842

  13. Properties and mechanisms of action of naturally occurring antifungal peptides.

    PubMed

    van der Weerden, Nicole L; Bleackley, Mark R; Anderson, Marilyn A

    2013-10-01

    Antimicrobial peptides are a vital component of the innate immune system of all eukaryotic organisms and many of these peptides have potent antifungal activity. They have potential application in the control of fungal pathogens that are a serious threat to both human health and food security. Development of antifungal peptides as therapeutics requires an understanding of their mechanism of action on fungal cells. To date, most research on antimicrobial peptides has focused on their activity against bacteria. Several antimicrobial peptides specifically target fungal cells and are not active against bacteria. Others with broader specificity often have different mechanisms of action against bacteria and fungi. This review focuses on the mechanism of action of naturally occurring antifungal peptides from a diverse range of sources including plants, mammals, amphibians, insects, crabs, spiders, and fungi. While antimicrobial peptides were originally proposed to act via membrane permeabilization, the mechanism of antifungal activity for these peptides is generally more complex and often involves entry of the peptide into the cell. PMID:23381653

  14. Naturally occurring and forced azimuthal modes in a turbulent jet

    NASA Technical Reports Server (NTRS)

    Raman, Ganesh; Rice, Edward J.; Reshotko, Eli

    1991-01-01

    Naturally occurring instability modes in an axisymmetric jet were studied using the modal frequency technique. The evolution of the modal spectrum was obtained for a jet with a Reynolds number based on a diameter of 400,000 for both laminar and turbulent nozzle boundary layers. In the early evolution of the jet the axisymmetric mode was predominant, with the azimuthal modes growing rapidly but dominating only the end of the potential core. The growth of the azimuthal was observed closer to the nozzle exit for the jet in the laminar boundary layer case than for the turbulent. Target modes for efficient excitation of the jet were determined and two cases of excitation were studied. First, a jet was excited simultaneously by two helical modes, m equals plus 1 and m equals minus 1 at a Strouhal number based on jet diameter of 0.15 and the axisymmetric mode, m equals 0 at a jet diameter of 0.6. Second, m equals plus one and m equals minus 1 at jet diameter equals 0.3 and m equals 0 at jet diameter equals 0.6 were excited simultaneously. The downstream evolution of the hydrodynamic modes and the spreading rate of the jet were documented for each case. Higher jet spreading rates, accompanied by distorted jet cross sections were observed for the cases where combinations of axisymmetric and helical forcings were applied.

  15. Characteristics of Cherenkov radiation in naturally occurring ice

    NASA Astrophysics Data System (ADS)

    Mikkelsen, R. E.; Poulsen, T.; Uggerhøj, U. I.; Klein, S. R.

    2016-03-01

    We revisit the theory of Cherenkov radiation in uniaxial crystals. Historically, a number of flawed attempts have been made at explaining this radiation phenomenon, and a consistent error-free description is nowhere available. We apply our calculation to a large modern day telescope—IceCube. Located in Antarctica, this detector makes use of the naturally occurring ice as a medium to generate Cherenkov radiation. However, due to the high pressure at the depth of the detector site, large volumes of hexagonal ice crystals are formed. We calculate how this affects the Cherenkov radiation yield and angular dependence. We conclude that the effect is small, at most about a percent, and would only be relevant in future high-precision instruments like e.g. Precision IceCube Next Generation Upgrade (PINGU). For radio-Cherenkov experiments which use the presence of a clear Cherenkov cone to determine the arrival direction, any variation in emission angle will directly and linearly translate into a change in apparent neutrino direction. In closing, we also describe a simple experiment to test this formalism and calculate the impact of anisotropy on light yields from lead tungstate crystals as used, for example, in the CMS calorimeter at the CERN LHC.

  16. Naturally-occurring anti-Jka in infant twins.

    PubMed

    Rumsey, D H; Nance, S J; Rubino, M; Sandler, S G

    1999-01-01

    Anti-Jka was detected by solid-phase red cell adherence (SPRCA) antibody detection and identification tests in the plasma of a 9-month-old female infant during a routine presurgical evaluation. The patient and her nonidentical twin sister, who also had anti-Jka in her plasma, were products of an uncomplicated in vitro fertilization, full-term pregnancy, and vaginal delivery. Neither twin had been transfused, recently infected, or treated with medication. Their mother had no prior pregnancies or transfusions. Red blood cells (RBCs) from the patient and her sister typed as Jk(a-b+) by direct hemagglutination, and this phenotype was confirmed by negative adsorption and elution studies. Both infants' plasma samples were strongly reactive with 20 examples of Jk(a+) RBCs and nonreactive with 20 examples of Jk(a-) RBCs by SPRCA assays. Anti-Jka was not detected in either twins' plasma by indirect antiglobulin tests by tube method in low-ionic- strength saline solution or polyethylene glycol, or with ficin- or papain-treated RBCs. Monocyte monolayer assays using Jk(a+) RBCs sensitized by either twins' serum were nonreactive (0%). RBCs from both parents typed as Jk(a+b+). Both parents' antibody detection test results by SPRCA assay were negative. The absence of a history of exposure to allogeneic RBCs or possible passive transfer of maternal or other alloantibody classifies these antibodies as naturally-occurring anti-Jka. PMID:15373637

  17. Solution of naturally-occurring glasses in the geological environment

    SciTech Connect

    Glass, B.P.

    1982-12-01

    As part of a study to investigate the feasibility of putting nuclear wastes in glass containers and burying them on land or dumping them in the ocean, we have made a study of the amount of solution experienced by naturally occurring glasses from two land sites and thirty-four deep-sea sites. The glasses used in this study are microtektites from three strewn fields (Australasian, Ivory Coast, and North American) and from the Zhamanshin impact crater in southern Siberia. The microtektites range in age from 0.7 to 35 m.y. and they have a wide range in composition. Although several criteria for determining the amount of solution were considered, most of the conclusions are based on two criteria: (1) width of cracks, and (2) elevation of silica-rich inclusions above the adjacent microtektite surface. The amount of solution was determined for about 170 microtektites; and measured amounts of solution range from 0.2 to at least 28 {mu}m, but most are less than 5 {mu}m. There appears to be no systematic relationship between age and amount of solution. 21 refs., 7 tabs.

  18. Naturally occurring mutants inform SHBG structure and function.

    PubMed

    Wu, Tsung-Sheng; Hammond, Geoffrey L

    2014-07-01

    SHBG transports and regulates the activities of androgens and estrogens. Several single nucleotide polymorphisms in the human SHBG gene have been linked to sex steroid-dependent diseases, including those associated with the metabolic syndrome. The N-terminal laminin G-like domain of SHBG includes binding sites for calcium, sex steroids, and fibulin family members, as well as a dimerization domain. We have found that 8 of 18 uncharacterized nonsynonymous single nucleotide polymorphisms within this domain alter the production or biochemical properties of SHBG in ways not previously recognized. O-Linked glycosylation at Thr7 is disrupted in SHBG T7N, whereas abnormal glycosylation of SHBG G195E limits its secretion. Three SHBG mutants (R135C, L165M, and E176K) bind estradiol with abnormally high affinity. SHBG R135C also has an increased interaction with fibulin-2. Two different substitutions within the dimer interface at R123 (R123H and R123C) reduce the affinity for 5?-dihydrotestosterone, while increasing the relative binding affinity for estradiol. SHBG T48I is defective in calcium binding, which leads to a defect in dimerization, reduced affinity for sex steroids, and an enhanced interaction with fibulin-2, which can all be restored by calcium supplementation. These naturally occurring mutants provide insight into SHBG structure and function, and defects in SHBG production or function need to be considered in the context of its utility as a biomarker of diseases. PMID:24892637

  19. Application of the Commission's recommendations to naturally occurring radioactive material.

    PubMed

    Lecomte, J-F

    2015-06-01

    Since publication of the 2007 Recommendations (ICRP Publication 103), the International Commission on Radiological Protection has focused on preparing a series of publications dedicated to different types of existing exposure situations, such as radon exposure, cosmic exposure in aviation, and exposure to naturally occurring radioactive material (NORM). The publication related to NORM will present the main types of corresponding activities, and describe the characteristics of NORM exposure. It will also develop a conceptual framework for the practical application of the Commission's system to NORM exposure. In particular, the publication will explain why NORM activities are generally considered to be existing exposure situations, and when some of them should be managed as planned exposure situations. It will indicate when the workers should be considered as occupationally exposed. It will also provide recommendations regarding application of the three principles of radiological protection. The need to consider the justification of the re-use or recycling of residues carefully will be highlighted. Guidance will be provided for selection of the reference level, and for implementation of the optimisation process through a graded approach including both prevention and mitigation of exposures. Flexibility will be recommended for the application of dose limits, notably when the situation is managed as a planned exposure situation. PMID:25816272

  20. Global distribution of naturally occurring marine hypoxia on continental margins

    NASA Astrophysics Data System (ADS)

    Helly, John J.; Levin, Lisa A.

    2004-09-01

    Hypoxia in the ocean influences biogeochemical cycling of elements, the distribution of marine species and the economic well being of many coastal countries. Previous delineations of hypoxic environments focus on those in enclosed seas where hypoxia may be exacerbated by anthropogenically induced eutrophication. Permanently hypoxic water masses in the open ocean, referred to as oxygen minimum zones, impinge on a much larger seafloor surface area along continental margins of the eastern Pacific, Indian and western Atlantic Oceans. We provide the first global quantification of naturally hypoxic continental margin floor by determining upper and lower oxygen minimum zone depth boundaries from hydrographic data and computing the area between the isobaths using seafloor topography. This approach reveals that there are over one million km 2 of permanently hypoxic shelf and bathyal sea floor, where dissolved oxygen is <0.5 ml l -1; over half (59%) occurs in the northern Indian Ocean. We also document strong variation in the intensity, vertical position and thickness of the OMZ as a function of latitude in the eastern Pacific Ocean and as a function of longitude in the northern Indian Ocean. Seafloor OMZs are regions of low biodiversity and are inhospitable to most commercially valuable marine resources, but support a fascinating array of protozoan and metazoan adaptations to hypoxic conditions.

  1. A nitrogen and sulfur isotope investigation of redox conditions occurring in a shallow outwash aquifer.

    NASA Astrophysics Data System (ADS)

    Spalding, R.; Hartke, E.

    2001-12-01

    The sources and distribution of elevated nitrate and sulfate concentrations were determined using nitrogen and sulfur isotopes in groundwater from an unconfined outwash aquifer located in Jackson County, southern Indiana. Land use is mostly agricultural. Local farmers apply nitrogeneous inorganic fertilizers to their fields. In addition, two commercial confined feedlots house over two million chickens, and wastes are stored in seven interconnected lagoons at the larger feedlot. These wastes are later applied to an adjacent field via spray irrigation. Over 50 shallow wells (5 m deep), domestic wells (7 m deep) and deep wells (15to 20 m deep) were sampled over a two- year period to monitor nitrogen and sulfur inputs from these sources. Most shallow groundwater in the study area is above the EPA drinking water standards for nitrate-N (>10 mgL). Nitrate concentrations are highest down gradient from the spray irrigation field (53.5 mgL), yet are also elevated in up gradient groundwaters. Nitrogen isotopes are enriched in the heavier isotope (d15N-NO3 > +13.7 ooo) down gradient from the large feedlot and lightest signatures (d15N-NO3 < +2.0 ooo) are found in up gradient groundwater underlying fields that use inorganic fertilizers. Analytes associated with feedlot wastes (sodium, potassium, chloride and sulfate) are also elevated down gradient from the larger feedlot. Deep groundwater has no nitrate and higher sulfate concentrations than shallow waters. In two sets of multi-level wells, enrichment in both oxygen and nitrogen isotopes indicates that denitrification may occur at two depths: 1) locally in shallow waters adjacent to the waste lagoons; and 2) in deeper waters (approximately 10 m) throughout the study area. Sulfate isotopic signatures in deep groundwater approach the signature of pyrite found within the outwash (d34S-SO4 = -11.6 ooo). Autotrophic denitrification may be occurring where nitrate is reduced and the oxidation of pyrite is adding sulfate with depth.

  2. Committed effective dose from naturally occuring radionuclides in shellfish

    NASA Astrophysics Data System (ADS)

    Khandaker, Mayeen Uddin; Wahib, Norfadira Binti; Amin, Yusoff Mohd.; Bradley, D. A.

    2013-07-01

    Recognizing their importance in the average Malaysian daily diet, the radioactivity concentrations in mollusc- and crustacean-based food have been determined for key naturally occuring radionuclides. Fresh samples collected from various maritime locations around peninsular Malaysia have been processed using standard procedures; the radionuclide concentrations being determined using an HPGe ?-ray spectrometer. For molluscs, assuming secular equilibrium, the range of activities of 238U (226Ra), 232Th (228Ra) and 40K were found to be 3.280.35 to 5.340.52, 1.200.21 to 2.440.21 and 1186 to 28114 Bq kg-1 dry weight, respectively. The respective values for crustaceans were 3.020.57 to 4.700.52, 1.380.21 to 2.400.35 and 21611 to 31615 Bq kg-1. The estimated average daily intake of radioactivity from consumption of molluscs are 0.37 Bq kg-1 for 238U (226Ra), 0.16 Bq kg-1 for 232Th (228Ra) and 18 Bq kg-1 for 40K; the respective daily intake values from crustaceans are 0.36 Bq kg-1, 0.16 Bq kg-1 and 23 Bq kg-1. Associated annual committed effective doses from molluscs are estimated to be in the range 21.3 to 34.7 ?Sv for 226Ra, 19.3 to 39.1 ?Sv for 228Ra and 17.0 to 40.4 ?Sv for 40K. For crustaceans, the respective dose ranges are 19.6 to 30.5 ?Sv, 22.0 to 38.4 ?Sv and 31.1 to 45.5 ?Sv, being some several times world average values.

  3. ORIGIN AND PROPERTIES OF NATURALLY OCCURRING HAPTEN FROM ESCHERICHIA COLI

    PubMed Central

    Anacker, R. L.; Finkelstein, R. A.; Haskins, W. T.; Landy, M.; Milner, K. C.; Ribi, E.; Stashak, P. W.

    1964-01-01

    Anacker, R. L. (National Institute of Allergy and Infectious Diseases, Rocky Mountain Laboratory, Hamilton, Mont.), R. A. Finkelstein, W. T. Haskins, M. Landy, K. C. Milner, E. Ribi, and P. W. Stashak. Origin and properties of naturally occurring hapten from Escherichia coli. J. Bacteriol. 88:1705–1720. 1964.—Haptens found in preparations of endotoxin and in fractions of disrupted cells, particularly one termed “native hapten,” which appeared to be associated with the protoplasm of cells rather than with cell walls, have been further investigated with a view to establishing their origin and composition as well as their host-reactive properties. For this purpose, cells from a smooth strain of Escherichia coli O111:B4 were either extracted directly or disrupted and separated into cell-wall and protoplasmic fractions. Haptens were obtained by gel filtration of endotoxins, by trichloroacetic acid extraction of protoplasm, and by a mild acid hydrolysis of endotoxin. Several lines of evidence indicated that native hapten originated in the protoplasm rather than by autolysis or degradation of cell-wall endotoxin during procedures employed in disruption. In gel diffusion and quantitative precipitin tests, no hapten was identical with endotoxin, but native hapten was serologically the most complex of the haptens and precipitated the most antibody. Native and acid haptens, on a weight basis, fixed about 1% of the quantity of complement fixed by homologous endotoxin. Haptens did not stimulate the production of antibodies in mice or rabbits and did not elicit endotoxic host reactions. Chemically, native hapten differed from endotoxin and from acid hapten in that it lacked phosphorus, heptose, long-chain fatty acids, and 2-keto-3-deoxyoctonate. These substances did not appear to be determinants of antigenic specificity, but they may provide necessary bonds for assembling hapten-like units into fully antigenic and toxic macromolecules. Images PMID:14240961

  4. Effect of naturally occurring tetrapyrroles on photooxidation in cow's milk.

    PubMed

    Airado-Rodrguez, Diego; Intawiwat, Natthorn; Skaret, Josefine; Wold, Jens Petter

    2011-04-27

    The objective of this work was to better understand the photosensitizing effect of riboflavin versus naturally occurring tetrapyrroles in cow's milk. This was done by exposure of milk samples to blue light (400-500 nm), which is absorbed by riboflavin and tetrapyrroles, orange light (575-750 nm), which is absorbed by tetrapyrroles but not riboflavin, and white light, which contains the entire visible region. The milk was exposed to about 1.6 W/m(2) in 20 h, and two different light sources were tested: HMI lamp and fluorescent light tubes used for commercial display. Sensory analysis showed that wavelengths longer than 575 nm induced significantly more off-flavors than wavelengths shorter than 500 nm. By fluorescence spectroscopy it was observed that tetrapyrroles, in particular, chlorophyllic compounds, were degraded more by orange light than by blue and that the degree of degradation correlated closely with the formation of sensory off-flavors. The fluorescent agent Singlet Oxygen Sensor Green (SOSG) was used to monitor the formation of singlet oxygen under the different light exposure conditions, and the method verified that singlet oxygen was formed in large proportions in milk exposed to wavelengths longer than 575 nm, presumably with minor or no involvement of riboflavin. The results suggest that cholorophyllic compounds are responsible for a major part of photooxidation in milk. It is also suggested that ?-carotene protects against photooxidation under blue light because it absorbs a major portion of the light below 500 nm and thereby reduces reactions with photosensitizers. PMID:21405085

  5. Role of naturally occurring gas hydrates in sediment transport

    SciTech Connect

    McIver, R.D.

    1982-06-01

    Naturally occurring gas hydrates have the potential to store enormous volumes of both gas and water in semi-solid form in ocean-bottom sediments and then to release that gas and water when the hydrate's equilibrium condition are disturbed. Therefore, hydrates provide a potential mechanism for transporting large volumes of sediments. Under the combined low bottom-water temperatures and moderate hydrostatic pressures that exist over most of the continental slopes and all of the continental rises and abyssal plains, hydrocarbon gases at or near saturation in the interstitial waters of the near-bottom sediments will form hydrates. The gas can either be autochthonous, microbially produced gas, or allochthonous, catagenic gas from deeper sediments. Equilibrium conditions that stabilize hydrated sediments may be disturbed, for example, by continued sedimentation or by lowering of sea level. In either case, some of the solid gas-water matrix decomposes. Released gas and water volume exceeds the volume occupied by the hydrate, so the internal pressure rises - drastically if large volumes of hydrate are decomposed. Part of the once rigid sediment is converted to a gas- and water-rich, relatively low density mud. When the internal pressure, due to the presence of the compressed gas or to buoyancy, is sufficiently high, the overlying sediment may be lifted and/or breached, and the less dense, gas-cut mud may break through. Such hydrate-related phenomena can cause mud diapirs, mud volcanos, mud slides, or turbidite flows, depending on sediment configuration and bottom topography. 4 figures.

  6. Naturally occurring asbestos: a recurring public policy challenge.

    PubMed

    Lee, R J; Strohmeier, B R; Bunker, K L; Van Orden, D R

    2008-05-01

    The potential environmental hazards and associated public health issues related to exposure to respirable dusts from the vicinity of natural in-place asbestos deposits (commonly referred to as naturally occurring asbestos, NOA) have gained the regulatory and media spotlight in many areas around the United States, such as Libby, MT, Fairfax County, VA, and El Dorado Hills, CA, among others. NOA deposits may be present in a variety of geologic formations. It has been suggested that airborne asbestos may be released from NOA deposits, and absent appropriate engineering controls, may pose a potential health hazard if these rocks are crushed or exposed to natural weathering and erosion or to human activities that create dust. The issue that needs to be addressed at a policy level is the method of assessing exposures to elongated rock fragments ubiquitous in dust clouds in these same environments and the associated risk. Elongated rock fragments and single crystal minerals present in NOA have been construed by some as having attributes, including the health effects, of asbestos fibers. However, the Occupational Safety and Health Administration (OSHA), Mine Safety and Health Administration (MSHA), and the Consumer Products Safety Commission (CPSC) found that the scientific evidence did not support this assumption. As in many environmental fields of study, the evidence is often disputed. Regulatory policy is not uniform on the subject of rock fragments, even within single agencies. The core of the issue is whether the risk parameters associated with exposures to commercial asbestos can or should be applied to rock fragments meeting an arbitrary set of particle dimensions used for counting asbestos fibers. Inappropriate inclusion of particles or fragments results in dilution of risk and needless expenditure of resources. On the other hand, inappropriate exclusion of particles or fragments may result in increased and unnecessary risk. Some of the fastest growing counties in the United States are in areas where NOA is known to exist and therefore this issue takes on national significance. This ongoing national dilemma has raised public and business concerns. There has been continuing political and scientific debate and widespread miscommunication over perceived versus actual health risks, the validity of various analytical sampling and testing methods, the questionable necessity and escalating costs of remediation procedures, and the combined negative impact on numerous commercial and public interests. Thus, conflicting research and regulatory positions on the distinctions between and hazards of true asbestos and ordinary rock fragments is all that is presently available to the public until the differing scientific communities and government agencies arrive at a consensus on these issues. The risk assessment methodology and the analytical technology needed to support inferences drawn from existing research are available, but have not been organized and implemented in the manner needed to resolve the NOA controversy. There should exist nationally adopted and peer-reviewed NOA standards (developed jointly by the scientific community, health risk professionals, and government regulators) that establish: (1) a scientific basis for risk evaluation and assessment of NOA and rock fragments; (2) accepted analytical protocols for determining if NOA actually exists in a given area and for separating NOA from related non-asbestos rock fragments and single crystal minerals; and (3) effective public policies for managing NOA, minimizing potential hazards, and protecting public health. This article will review some of the key issues involved with the current NOA debate, propose improved analytical methodologies, describe potential solutions for dealing with NOA, and outline the benefits to be gained by creating a practical national NOA public policy. PMID:18180100

  7. Probabilities of Natural Events Occurring at Savannah River Plant

    SciTech Connect

    Huang, J.C.

    2001-07-17

    This report documents the comprehensive evaluation of probability models of natural events which are applicable to Savannah River Plant. The probability curves selected for these natural events are recommended to be used by all SRP/SRL safety analysts. This will ensure a consistency in analysis methodology for postulated SAR incidents involving natural phenomena.

  8. Mitochondrial catalase suppresses naturally occurring lung cancer in old mice

    PubMed Central

    Ge, Xuang; Pettan-Brewer, Christina; Morton, John; Carter, Katrina; Fatemi, Sy; Rabinovitch, Peter; Ladiges, Warren C.

    2015-01-01

    Lung cancer is generally difficult to detect until the late stages of disease, when it is much more difficult to treat because of the more aggressive and invasive behavior. Advanced lung cancer is much more common in older adults making it even more challenging to treat. Adenocarcinoma belongs to a category of non-small cell lung cancers, which comprise up to 40% of all lung cancers, and about half of these have an activating K-ras mutation. Because treatment relapses are common, more effective unconventional treatment and prevention methods are needed. In this regard, the antioxidant enzyme catalase targeted to mitochondria (mCAT) has been shown to delay aging and cancer in mice, and the progression of transgenic oncogene and syngeneic tumors was suppressed, helping support the notion that attenuation of mitochondria-generated hydrogen peroxide signaling is associated with an antitumor effect. In order to determine if mCAT has any effect on naturally occurring lung cancer of the adenocarcinoma type in old mice, the tumor incidence and progression were examined in the lungs of old mCAT transgenic and wild-type (WT) mice with a CB6F1 (Balb/c X C57BL/6) background. CB6F1 mice with a WT genotype were found to have a high incidence of adenomas at 24 months of age, which progressed to adenocarcinomas at 32 months of age. CB6F1 mice with the mCAT genotype had significantly reduced incidence and severity of lung tumors at both ages. Fibroblasts isolated from the lungs of old mCAT mice, but not WT mice, were shown to secrete soluble factors that inhibited lung tumor cell growth suggesting that stromal fibroblasts play a role in mediating the antitumor effects of mCAT. The aged CB6F1 mouse, with its high incidence of K-ras mutant lung cancer, is an excellent model to further study the anticancer potential of mitochondria-targeted therapy. PMID:26400209

  9. Manufactured Home Testing in Simulated and Naturally Occurring High Winds

    SciTech Connect

    W. D. Richins; T. K. Larson

    2006-08-01

    A typical double-wide manufactured home was tested in simulated and naturally occurring high winds to understand structural behavior and improve performance during severe windstorms. Seven (7) lateral load tests were conducted on a double-wide manufactured home at a remote field test site in Wyoming. An extensive instrumentation package monitored the overall behavior of the home and collected data vital to validating computational software for the manufactured housing industry. The tests were designed to approach the design load of the home without causing structural damage, thus allowing the behavior of the home to be accessed when the home was later exposed to high winds (to 80-mph). The data generally show near-linear initial system response with significant non-linear behavior as the applied loads increase. Load transfer across the marriage line is primarily compression. Racking, while present, is very small. Interface slip and shear displacement along the marriage line are nearly insignificant. Horizontal global displacements reached 0.6 inch. These tests were designed primarily to collect data necessary to calibrate a desktop analysis and design software tool, MHTool, under development at the Idaho National Laboratory specifically for manufactured housing. Currently available analysis tools are, for the most part, based on methods developed for “stick built” structures and are inappropriate for manufactured homes. The special materials utilized in manufactured homes, such as rigid adhesives used in the connection of the sheathing materials to the studs, significantly alter the behavior of manufactured homes under lateral loads. Previous full scale tests of laterally loaded manufactured homes confirm the contention that conventional analysis methods are not applicable. System behavior dominates the structural action of manufactured homes and its prediction requires a three dimensional analysis of the complete unit, including tiedowns. This project was sponsored by the US Department of Energy, US Department of Housing and Urban Development, and the Manufactured Housing Institute. The results of this research can lead to savings in annual losses of life and property by providing validated information to enable the advancement of code requirements and by developing engineering software that can predict and optimize wind resistance.

  10. Ammonite habitat revealed via isotopic composition and comparisons with co-occurring benthic and planktonic organisms

    PubMed Central

    Sessa, Jocelyn Anne; Larina, Ekaterina; Knoll, Katja; Garb, Matthew; Cochran, J. Kirk; Huber, Brian T.; MacLeod, Kenneth G.; Landman, Neil H.

    2015-01-01

    Ammonites are among the best-known fossils of the Phanerozoic, yet their habitat is poorly understood. Three common ammonite families (Baculitidae, Scaphitidae, and Sphenodiscidae) co-occur with well-preserved planktonic and benthic organisms at the type locality of the upper Maastrichtian Owl Creek Formation, offering an excellent opportunity to constrain their depth habitats through isotopic comparisons among taxa. Based on sedimentary evidence and the micro- and macrofauna at this site, we infer that the 9-m-thick sequence was deposited at a paleodepth of 70–150 m. Taxa present throughout the sequence include a diverse assemblage of ammonites, bivalves, and gastropods, abundant benthic foraminifera, and rare planktonic foraminifera. No stratigraphic trends are observed in the isotopic data of any taxon, and thus all of the data from each taxon are considered as replicates. Oxygen isotope-based temperature estimates from the baculites and scaphites overlap with those of the benthos and are distinct from those of the plankton. In contrast, sphenodiscid temperature estimates span a range that includes estimates of the planktonic foraminifera and of the warmer half of the benthic values. These results suggest baculites and scaphites lived close to the seafloor, whereas sphenodiscids sometimes inhabited the upper water column and/or lived closer to shore. In fact, the rarity and poorer preservation of the sphenodiscids relative to the baculites and scaphites suggests that the sphenodiscid shells may have only reached the Owl Creek locality by drifting seaward after death. PMID:26630003

  11. Ammonite habitat revealed via isotopic composition and comparisons with co-occurring benthic and planktonic organisms.

    PubMed

    Sessa, Jocelyn Anne; Larina, Ekaterina; Knoll, Katja; Garb, Matthew; Cochran, J Kirk; Huber, Brian T; MacLeod, Kenneth G; Landman, Neil H

    2015-12-22

    Ammonites are among the best-known fossils of the Phanerozoic, yet their habitat is poorly understood. Three common ammonite families (Baculitidae, Scaphitidae, and Sphenodiscidae) co-occur with well-preserved planktonic and benthic organisms at the type locality of the upper Maastrichtian Owl Creek Formation, offering an excellent opportunity to constrain their depth habitats through isotopic comparisons among taxa. Based on sedimentary evidence and the micro- and macrofauna at this site, we infer that the 9-m-thick sequence was deposited at a paleodepth of 70-150 m. Taxa present throughout the sequence include a diverse assemblage of ammonites, bivalves, and gastropods, abundant benthic foraminifera, and rare planktonic foraminifera. No stratigraphic trends are observed in the isotopic data of any taxon, and thus all of the data from each taxon are considered as replicates. Oxygen isotope-based temperature estimates from the baculites and scaphites overlap with those of the benthos and are distinct from those of the plankton. In contrast, sphenodiscid temperature estimates span a range that includes estimates of the planktonic foraminifera and of the warmer half of the benthic values. These results suggest baculites and scaphites lived close to the seafloor, whereas sphenodiscids sometimes inhabited the upper water column and/or lived closer to shore. In fact, the rarity and poorer preservation of the sphenodiscids relative to the baculites and scaphites suggests that the sphenodiscid shells may have only reached the Owl Creek locality by drifting seaward after death. PMID:26630003

  12. Natural mercury isotope variation in coal deposits and organic soils

    SciTech Connect

    Abir, Biswas; Joel D. Blum; Bridget A. Bergquist; Gerald J. Keeler; Zhouqing Xie

    2008-11-15

    There is a need to distinguish among sources of Hg to the atmosphere in order to more fully understand global Hg pollution. In this study we investigate whether coal deposits within the United States, China, and Russia-Kazakhstan, which are three of the five greatest coal-producing regions, have diagnostic Hg isotopic fingerprints that can be used to discriminate among Hg sources. We also investigate the Hg isotopic composition of modern organic soil horizons developed in areas distant from point sources of Hg in North America. Mercury stored in coal deposits displays a wide range of both mass dependent fractionation and mass independent fractionation. {delta}{sup 202}Hg varies in coals by 3{per_thousand} and {Delta}{sup 201}Hg varies by 0.9{per_thousand}. Combining these two Hg isotope signals results in what may be a unique isotopic 'fingerprint' for many coal deposits. Mass independent fractionation of mercury has been demonstrated to occur during photochemical reactions of mercury. This suggests that Hg found in most coal deposits was subjected to photochemical reduction near the Earth's surface prior to deposition. The similarity in MDF and MIF of modern organic soils and coals from North America suggests that Hg deposition from coal may have imprinted an isotopic signature on soils. This research offers a new tool for characterizing mercury inputs from natural and anthropogenic sources to the atmosphere and provides new insights into the geochemistry of mercury in coal and soils. 35 refs., 2 figs., 1 tab.

  13. Biosynthesis of toxic naturally-occurring seafood contaminants.

    PubMed

    Kalaitzis, John A; Chau, Rocky; Kohli, Gurjeet S; Murray, Shauna A; Neilan, Brett A

    2010-08-15

    Outbreaks of human illness caused by the consumption of contaminated seafood, continues to be a major problem particularly for the shellfish industry. Toxins from marine, brackish and freshwater environments, which are often produced as a result of harmful algal blooms, have been implicated as the causative agents of these poisonings. Commonly, poisoning events have been grouped into one of six classes, Paralytic Shellfish Poisoning (PSP), Diarrhetic Shellfish Poisoning (DSP), Neurotoxic Shellfish Poisoning (NSP), Ciguatera Fish Poisoning (CFP), Azaspiracid Shellfish Poisoning (AZP), and Amnesiac Shellfish Poisoning (ASP). The causative agents of these specific poisonings along with their biosyntheses are discussed in this review. The highly unusual and complex structures of most common seafood toxins have made them interesting targets for biosynthetic studies. Many of the toxins presented are biosynthesized via complex pathways that have been elucidated either through isotope labelled precursor feeding studies and/or characterization of the genes encoding the producing organism's biosynthetic machinery. Feeding studies key to our understanding of a particular toxin's biosynthesis, such as the incorporation of unusual precursors, as well as unique biosynthetic pathways and rare chemical mechanisms involved in the assembly process are highlighted. More recently, however, modern genomics-based techniques have been used for the elucidation of biosynthetic pathways and these are presented in the context of polyketide, non-ribosomal peptide, and hybrid pathway derived, toxin assembly. PMID:19761784

  14. Overview of naturally occurring Earth materials and human health concerns

    NASA Astrophysics Data System (ADS)

    Ernst, W. G.

    2012-10-01

    The biosphere and the Earth's critical zone have maintained a dynamic equilibrium for more than 3.5 billion years. Except for solar energy, almost all terrestrial substances necessary for life have been derived from near-surface portions of the land, hydrosphere, and atmosphere. If aggregate biological activities are less than the rate of nutrient supply and/or resource renewal, sustained population growth is possible. Where the replenishment rate of a life-sustaining Earth material is finite, usage may reach a condition of dynamic equilibrium in which biological consumption equals but on average cannot exceed the overall supply. Although large, most natural resources are present in finite abundances; for such commodities, excessive present-day human utilization reduces future availability, and thus the ultimate planetary carrying capacity for civilization. Intensive use of Earth materials has enhanced the quality of life, especially in the developed nations. Still, natural background levels, and Earth processes such as volcanic eruptions, as well as human activities involving agriculture, construction, and the extraction, refining, and transformation of mineral resources have led to harmful side effects involving environmental degradation and public health hazards. Among naturally and anthropogenically induced risks are bioaccessible airborne dusts and gases, soluble pollutants in agricultural, industrial, and residential waters, and toxic chemical species in foods and manufactured products. At appropriate levels of ingestion, many Earth materials are necessary for existence, but underdoses and overdoses have mild to serious consequences for human health and longevity. This overview briefly sketches several natural resource health hazards. Included are volcanic ash + aerosols + gases, mineral dusts, non-volcanic aerosols + nanoparticles, asbestos + fibrous zeolites, arsenic, fluorine, iodine, uranium + thorium + radium + radon + polonium, selenium, mercury, copper, lead, chromium, and cadmium. Also noted are health effects of natural disasters, and an obligatory future sustainable consumption of natural resources. Not treated are the overwhelming adverse effects of malnutrition, lack of potable water, inadequate sanitation, fossil fuel usage, mining, manufacturing, and agricultural pollution, or environmental pathogens, nor are the important impacts of complex mixtures of Earth materials considered. With rise of the worldwide information network, economic globalization, and the industrial thrust of Developing Nations, the achievement of natural resource sustainability has emerged as a strategic imperative. Accompanying increased rates of Earth materials consumption and attendant environmental change, substantially improved, universal public health will require a major global effort, integrating collaborations among geoscientists, medical researchers, and epidemiologists. Governments and NGOs must provide important support of such cooperative efforts, and both health and Earth scientists must cross disciplinary and national boundaries.

  15. Geochemistry of a naturally occurring massive marine gas hydrate

    USGS Publications Warehouse

    Kvenvolden, K.A.; Claypool, G.E.; Threlkeld, C.N.; Dendy, Sloan E.

    1984-01-01

    During Deep Sea Drilling Project (DSDP) Leg 84 a core 1 m long and 6 cm in diameter of massive gas hydrate was unexpectedly recovered at Site 570 in upper slope sediment of the Middle America Trench offshore of Guatemala. This core contained only 5-7% sediment, the remainder being the solid hydrate composed of gas and water. Samples of the gas hydrate were decomposed under controlled conditions in a closed container maintained at 4??C. Gas pressure increased and asymptotically approached the equilibrium decomposition pressure for an ideal methane hydrate, CH4.5-3/4H2O, of 3930 kPa and approached to this pressure after each time gas was released, until the gas hydrate was completely decomposed. The gas evolved during hydrate decomposition was 99.4% methane, ???0.2% ethane, and ???0.4% CO2. Hydrocarbons from propane to heptane were also present, but in concentrations of less than 100 p.p.m. The carbon-isotopic composition of methane was -41 to -44 permil(( 0 00), relative to PDB standard. The observed volumetric methane/water ratio was 64 or 67, which indicates that before it was stored and analyzed, the gas hydrate probably had lost methane. The sample material used in the experiments was likely a mixture of methane hydrate and water ice. Formation of this massive gas hydrate probably involved the following processes: (i) upward migration of gas and its accumulation in a zone where conditions favored the growth of gas hydrates, (ii) continued, unusually rapid biological generation of methane, and (iii) release of gas from water solution as pressure decreased due to sea level lowering and tectonic uplift. ?? 1984.

  16. Interactions between plasma proteins and naturally occurring polyphenols.

    PubMed

    Li, Min; Hagerman, Ann E

    2013-05-01

    The plant natural products known as polyphenols are found at micronutrient levels in fruits, vegetables, and plant-based beverages such as wine, tea, coffee and cocoa. Consumption of a fruit- and vegetable-rich diet, the "Mediterranean diet", has been epidemiologically related to health benefits especially for chronic diseases including diabetes, cardiovascular disease, and Alzheimer's disease. The abundance of polyphenols in plant-rich diets, and the potent bioactivities of polyphenols, provide indirect evidence for a role for polyphenols in maintaining good health. However, molecular mechanisms for therapeutic or preventative activity have not been demonstrated in vivo. We summarize the chemical classes of natural polyphenols, their bioactivities and bioavailability and metabolism. Because many polyphenols bind protein, we focus on the potential of protein binding to mediate the health-related effects of polyphenols. We discuss interactions with plasma proteins as the first target organ past the digestive tract for these orally-ingested compounds. PMID:23330924

  17. Shear wave filtering in naturally-occurring Bouligand structures.

    PubMed

    Guarn-Zapata, Nicols; Gomez, Juan; Yaraghi, Nick; Kisailus, David; Zavattieri, Pablo D

    2015-09-01

    Wave propagation was investigated in the Bouligand-like structure from within the dactyl club of the stomatopod, a crustacean that is known to smash their heavily shelled preys with high accelerations. We incorporate the layered nature in a unitary material cell through the propagator matrix formalism while the periodic nature of the material is considered via Bloch boundary conditions as applied in the theory of solid state physics. Our results show that these materials exhibit bandgaps at frequencies related to the stress pulse generated by the impact of the dactyl club to its prey, and therefore exhibiting wave filtering in addition to the already known mechanisms of macroscopic isotropic behavior and toughness. PMID:25983314

  18. Going Wild: Lessons from Naturally Occurring T-Lymphotropic Lentiviruses

    PubMed Central

    VandeWoude, Sue; Apetrei, Cristian

    2006-01-01

    Over 40 nonhuman primate (NHP) species harbor species-specific simian immunodeficiency viruses (SIVs). Similarly, more than 20 species of nondomestic felids and African hyenids demonstrate seroreactivity against feline immunodeficiency virus (FIV) antigens. While it has been challenging to study the biological implications of nonfatal infections in natural populations, epidemiologic and clinical studies performed thus far have only rarely detected increased morbidity or impaired fecundity/survival of naturally infected SIV- or FIV-seropositive versus -seronegative animals. Cross-species transmissions of these agents are rare in nature but have been used to develop experimental systems to evaluate mechanisms of pathogenicity and to develop animal models of HIV/AIDS. Given that felids and primates are substantially evolutionarily removed yet demonstrate the same pattern of apparently nonpathogenic lentiviral infections, comparison of the biological behaviors of these viruses can yield important implications for host-lentiviral adaptation which are relevant to human HIV/AIDS infection. This review therefore evaluates similarities in epidemiology, lentiviral genotyping, pathogenicity, host immune responses, and cross-species transmission of FIVs and factors associated with the establishment of lentiviral infections in new species. This comparison of consistent patterns in lentivirus biology will expose new directions for scientific inquiry for understanding the basis for virulence versus avirulence. PMID:17041142

  19. Verification of mid-ocean ballast water exchange using naturally occurring coastal tracers.

    PubMed

    Murphy, Kathleen; Boehme, Jennifer; Coble, Paula; Cullen, Jay; Field, Paul; Moore, Willard; Perry, Elgin; Sherrell, Robert; Ruiz, Gregory

    2004-04-01

    We examined methods for verifying whether or not ships have performed mid-ocean ballast water exchange (BWE) on four commercial vessels operating in the Pacific and Atlantic Oceans. During BWE, a ship replaces the coastal water in its ballast tanks with water drawn from the open ocean, which is considered to harbor fewer organisms capable of establishing in coastal environments. We measured concentrations of several naturally occurring chemical tracers (salinity, six trace elements, colored dissolved organic matter fluorescence and radium isotopes) along ocean transects and in ballast tanks subjected to varying degrees of BWE (0-99%). Many coastal tracers showed significant concentration changes due to BWE, and our ability to detect differences between exchanged and unexchanged ballast tanks was greatest under multivariate analysis. An expanded dataset, which includes additional geographic regions, is now needed to test the generality of our results. PMID:15041428

  20. Virological and serological findings in dogs with naturally occurring distemper.

    PubMed

    Elia, Gabriella; Camero, Michele; Losurdo, Michele; Lucente, Maria Stella; Larocca, Vittorio; Martella, Vito; Decaro, Nicola; Buonavoglia, Canio

    2015-03-01

    Canine distemper virus (CDV) is the cause of a severe and highly contagious disease in dogs. The unpredictable and variable course of CDV-related disease may hamper correct diagnosis of infection and makes it crucial the collection of samples suitable for laboratory confirmation. In the present study we were able to follow the disease in two dogs infected naturally, collecting different biological matrices during the entire period of infection. By real time RT-PCR, viral RNA was detected and quantified, suggesting that urine and rectal swabs would be useful for ante-mortem diagnosis of distemper in dogs, regardless of the clinical stage and form of the illness. PMID:25512131

  1. Polyomavirus and Naturally Occuring Neuroglial Tumors in Raccoons (Procyon Lotor).

    PubMed

    Pesavento, Patricia A; Brostoff, Terza; Church, Molly E; Dela Cruz, Florante N; Woolard, Kevin D

    2016-02-24

    Polyomavirus (PyV) infections are widespread in human populations and, although generally associated with silent persistence, rarely cause severe disease. Among diseases convincingly associated with natural PyV infections of humans, there are remarkably different tissue tropisms and outcomes, including progressive multifocal leukoencephalopathy, transient or progressive nephropathy, and cancer. The variable character and unpredictable outcomes of infection attest to large gaps in our basic understanding of PyV biology. In particular, the rich history of research demonstrating the oncogenic potential of PyVs in laboratory animals begs the question of why cancer is not more often associated with infection. Raccoon polyomavirus (RacPyV), discovered in 2010, is consistently identified in neuroglial tumors in free-ranging raccoons in the western United States. Exposure to RacPyV is widespread, and RacPyV is detected in tissues of raccoons without tumors. Studying the relationship of RacPyV with its natural host is a unique opportunity to uncover cogent cellular targets and protein interactions between the virus and its host. Our hypothesis is that RacPyV, as an intact episome, alters cellular pathways within neural progenitor cells and drives oncogenesis. PMID:26912716

  2. The Frequency, Nature, and Effects of Naturally Occurring Appearance-Focused Social Comparisons

    ERIC Educational Resources Information Center

    Leahey, Tricia M.; Crowther, Janis H.; Mickelson, Kristin D.

    2007-01-01

    This research examined the effects of naturally occurring appearance-focused social comparisons on women's affect, body satisfaction, and weight-related cognitions. During their daily activities, women reporting body dissatisfaction (n = 53) and women reporting body satisfaction (n = 34) recorded their reactions to comparison information.

  3. The Frequency, Nature, and Effects of Naturally Occurring Appearance-Focused Social Comparisons

    ERIC Educational Resources Information Center

    Leahey, Tricia M.; Crowther, Janis H.; Mickelson, Kristin D.

    2007-01-01

    This research examined the effects of naturally occurring appearance-focused social comparisons on women's affect, body satisfaction, and weight-related cognitions. During their daily activities, women reporting body dissatisfaction (n = 53) and women reporting body satisfaction (n = 34) recorded their reactions to comparison information.…

  4. Natural abundance variations in stable isotopes and their potential uses in animal physiological ecology.

    PubMed

    Gannes, L Z; Martínez del Rio, C; Koch, P

    1998-03-01

    Chemical, biological, and physical processes lead to distinctive "isotopic signatures" in biological materials that allow tracing of the origins of organic substances. Isotopic variation has been extensively used by plant physiological ecologists and by paleontologists, and recently ecologists have adopted the use of stable isotopes to measure ecosystem patterns and processes. To date, animal physiological ecologists have made minimal use of naturally occurring stable isotopes as tracers. Here we provide a review of the current and potential uses of naturally occurring stable isotopes in animal physiological ecology. We outline the physical and biological processes that lead to variation in isotopic abundance in plants and animals. We summarize current uses in animal physiological ecology (diet reconstruction and animal movement patterns), and suggest areas of research where the use of stable isotopes can be fruitful (protein balance and turnover and the allocation of dietary nutrients). We argue that animal physiological ecologists can benefit from including the measurement of naturally occurring stable isotopes in their battery of techniques. We also argue that animal physiologists can make an important contribution to the emerging field of stable isotopes in biology by testing experimentally the plethora of assumptions upon which the techniques rely. PMID:9683412

  5. Structures and Properties of Naturally Occurring Polyether Antibiotics

    PubMed Central

    Rutkowski, Jacek; Brzezinski, Bogumil

    2013-01-01

    Polyether ionophores represent a large group of natural, biologically active substances produced by Streptomyces spp. They are lipid soluble and able to transport metal cations across cell membranes. Several of polyether ionophores are widely used as growth promoters in veterinary. Polyether antibiotics show a broad spectrum of bioactivity ranging from antibacterial, antifungal, antiparasitic, antiviral, and tumour cell cytotoxicity. Recently, it has been shown that some of these compounds are able to selectively kill cancer stem cells and multidrug-resistant cancer cells. Thus, they are recognized as new potential anticancer drugs. The biological activity of polyether ionophores is strictly connected with their molecular structure; therefore, the purpose of this paper is to present an overview of their formula, molecular structure, and properties. PMID:23586016

  6. Naturally occurring clinical reticuloendotheliosis in turkeys and chickens.

    PubMed

    Okoye, J O; Ezema, W; Agoha, J N

    1993-06-01

    Outbreaks of clinical reticuloendotheliosis (RE) were observed in a turkey flock and two pullet flocks. Clinical signs in turkeys included sleepiness, weakness, anorexia, diarrhoea and reduced egg production. The pullets showed severe emaciation, loss of back feathers, anorexia and diarrhoea. Fifteen out of 54 turkeys died before the flock was killed. One pullet flock suffered 20% mortality while the other had an average daily mortality of four to six out of 2000 birds for 9 weeks with a total mortality of 16.4%. Necropsy of the dead turkeys and pullets showed neoplastic nodules or grey foci in the internal organs especially the liver, intestines and spleen. Histopathological sections of the organs had proliferation of reticular cells with necrosis of the parenchyma and focal lymphocytic infiltration. RE virus antigens and precipitating antibodies were detected in the serum samples collected from the birds. It was suspected that natural RE could be a more serious problem than earlier reported in some countries. PMID:18671014

  7. Serum concentration of sialic acids in naturally occurring ovine babesiosis.

    PubMed

    Esmaeilnejad, Bijan; Tavassoli, Mousa; Asri-Rezaei, Siamak; Dalir-Naghadeh, Bahram; Abtahi Froushani, Seyyed Meysam; Arjmand, Jafar; Golabi, Mostafa

    2014-10-01

    This study is designated to assess the effect of the severity of Babesia ovis infection on sialic acid concentration in blood sera in naturally infected sheep. Infected animals (diseased group) comprised 38 Iranian fat-tailed sheep, about 1-3 years old, naturally infected with B. ovis, divided into four subgroups with respect to parasitemia rates (low 0.1-0.3 %, moderate 0.4-0.9 %, high 1-2.5 %, and very high >2.5 %). The parasitological diagnosis was confirmed using PCR analysis. As a control group, ten clinically healthy sheep reared under the same management and environmental conditions were also sampled. Hematological parameters and the concentrations of total sialic acid (TSA), lipid-bound sialic acid (LBSA), and protein-bound sialic acid (PBSA) were measured in both groups. Compared to controls, sialic acid concentrations showed significant increase (p?

  8. Natural isotope correction of MS/MS measurements for metabolomics and (13) C fluxomics.

    PubMed

    Niedenführ, Sebastian; Ten Pierick, Angela; van Dam, Patricia T N; Suarez-Mendez, Camilo A; Nöh, Katharina; Wahl, S Aljoscha

    2016-05-01

    Fluxomics and metabolomics are crucial tools for metabolic engineering and biomedical analysis to determine the in vivo cellular state. Especially, the application of (13) C isotopes allows comprehensive insights into the functional operation of cellular metabolism. Compared to single MS, tandem mass spectrometry (MS/MS) provides more detailed and accurate measurements of the metabolite enrichment patterns (tandem mass isotopomers), increasing the accuracy of metabolite concentration measurements and metabolic flux estimation. MS-type data from isotope labeling experiments is biased by naturally occurring stable isotopes (C, H, N, O, etc.). In particular, GC-MS(/MS) requires derivatization for the usually non-volatile intracellular metabolites introducing additional natural isotopes leading to measurements that do not directly represent the carbon labeling distribution. To make full useof LC- and GC-MS/MS mass isotopomer measurements, the influence of natural isotopes has to be eliminated (corrected). Our correction approach is analyzed for the two most common applications; (13) C fluxomics and isotope dilution mass spectrometry (IDMS) based metabolomics. Natural isotopes can have an impact on the calculated flux distribution which strongly depends on the substrate labeling and the actual flux distribution. Second, we show that in IDMS based metabolomics natural isotopes lead to underestimated concentrations that can and should be corrected with a nonlinear calibration. Our simulations indicate that the correction for natural abundance in isotope based fluxomics and quantitative metabolomics is essential for correct data interpretation. Biotechnol. Bioeng. 2016;113: 1137-1147. © 2015 Wiley Periodicals, Inc. PMID:26479486

  9. Sexual conflict and cooperation under naturally occurring male enforced monogamy.

    PubMed

    Montrose, V T; Harris, W E; Moore, P J

    2004-03-01

    An evolutionary conflict often exists between the sexes in regard to female mating patterns. Females can benefit from polyandry, whereas males mating with polyandrous females lose reproductive opportunities because of sperm competition. Where this conflict occurs, the evolution of mechanisms whereby males can control female remating, often at a fitness cost to the female, are expected to evolve. The fitness cost to the female will be increased in systems where a few high status males monopolise mating opportunities and thus have limited sperm supplies. Here we show that in the cockroach Nauphoeta cinerea, a species where males enforce female monogamy in the first reproductive cycle, males that have become sperm depleted continue to be able to manipulate female remating behaviour. Although the manipulation severely decreases fecundity in females mated to sperm-depleted males, males benefit, increasing their relative fitness by preventing other males from reproducing. Our results suggest that there is selection on maintaining the mechanism of manipulation rather than maintaining sperm numbers. Taken with previous research on sexual conflict in N. cinerea, this study suggests that the causes and consequences of sexual conflict are complex and can change across the life history of an individual. PMID:15009277

  10. Evidence of sublaminar drag naturally occurring in a curved pipe

    NASA Astrophysics Data System (ADS)

    Noorani, A.; Schlatter, P.

    2015-03-01

    Steady and unsteady flows in a mildly curved pipe for a wide range of Reynolds numbers are examined with direct numerical simulation. It is shown that in a range of Reynolds numbers in the vicinity of Reb ≈ 3400, based on bulk velocity and pipe diameter, a marginally turbulent flow is established in which the friction drag naturally reduces below the laminar solution at the same Reynolds number. The obtained values for friction drag for the laminar and turbulent (sublaminar) flows turn out to be in excellent agreement with experimental measurements in the literature. Our results are also in agreement with Fukagata et al. ["On the lower bound of net driving power in controlled duct flows," Phys. D 238, 1082 (2009)], as the lower bound of net power required to drive the flow, i.e., the pressure drop of the Stokes solution, is still lower than our marginally turbulent flow. A large-scale traveling structure that is thought to be responsible for that behaviour is identified in the instantaneous field. This mode could also be extracted using proper orthogonal decomposition. The effect of this mode is to redistribute the mean flow in the circular cross section which leads to lower gradients at the wall compared to the laminar flow.

  11. Evidence of sublaminar drag naturally occurring in a curved pipe

    SciTech Connect

    Noorani, A.; Schlatter, P.

    2015-03-15

    Steady and unsteady flows in a mildly curved pipe for a wide range of Reynolds numbers are examined with direct numerical simulation. It is shown that in a range of Reynolds numbers in the vicinity of Re{sub b} ≈ 3400, based on bulk velocity and pipe diameter, a marginally turbulent flow is established in which the friction drag naturally reduces below the laminar solution at the same Reynolds number. The obtained values for friction drag for the laminar and turbulent (sublaminar) flows turn out to be in excellent agreement with experimental measurements in the literature. Our results are also in agreement with Fukagata et al. [“On the lower bound of net driving power in controlled duct flows,” Phys. D 238, 1082 (2009)], as the lower bound of net power required to drive the flow, i.e., the pressure drop of the Stokes solution, is still lower than our marginally turbulent flow. A large-scale traveling structure that is thought to be responsible for that behaviour is identified in the instantaneous field. This mode could also be extracted using proper orthogonal decomposition. The effect of this mode is to redistribute the mean flow in the circular cross section which leads to lower gradients at the wall compared to the laminar flow.

  12. Naturally occurring compounds affect glutamatergic neurotransmission in rat brain.

    PubMed

    Martini, Lucia Helena; Jung, Fernanda; Soares, Felix Antunes; Rotta, Liane Nanci; Vendite, Deusa Aparecida; Frizzo, Marcos Emilio dos Santos; Yunes, Rosendo A; Calixto, Joo Batista; Wofchuk, Susana; Souza, Diogo O

    2007-11-01

    Natural products, including those derived from plants, have largely contributed to the development of therapeutic drugs. Glutamate is the main excitatory neurotransmitter in the central nervous system and it is also considered a nociceptive neurotransmitter, by acting on peripheral nervous system. For this reason, in this study we investigated the effects of the hydroalcoholic extracts from Drymis winteri (polygodial and drimanial), Phyllanthus (rutin and quercetine), Jathopha elliptica (jatrophone), Hedyosmum brasiliense (13HDS), Ocotea suaveolens (Tormentic acid), Protium kleinii (alphabeta-amyrin), Citrus paradise (naringin), soybean (genistein) and Crataeva nurvala (lupeol), described as having antinociceptive effects, on glutamatergic transmission parameters, such as [(3)H]glutamate binding, [(3)H]glutamate uptake by synaptic vesicles and astrocyte cultures, and synaptosomal [(3)H]glutamate release. All the glutamatergic parameters were affected by one or more of these compounds. Specifically, drimanial and polygodial presented more broad and profound effects, requiring more investigation on their mechanisms. The putative central side effects of these compounds, via the glutamatergic system, are discussed. PMID:17577666

  13. Naturally Occurring Variants of the Dysglycemic Peptide Pancreastatin

    PubMed Central

    Allu, Prasanna K. R.; Chirasani, Venkat R.; Ghosh, Dhiman; Mani, Anitha; Bera, Amal K.; Maji, Samir K.; Senapati, Sanjib; Mullasari, Ajit S.; Mahapatra, Nitish R.

    2014-01-01

    Pancreastatin (PST), a chromogranin A-derived peptide, is a potent physiological inhibitor of glucose-induced insulin secretion. PST also triggers glycogenolysis in liver and reduces glucose uptake in adipocytes and hepatocytes. Here, we probed for genetic variations in PST sequence and identified two variants within its functionally important carboxyl terminus domain: E287K and G297S. To understand functional implications of these amino acid substitutions, we tested the effects of wild-type (PST-WT), PST-287K, and PST-297S peptides on various cellular processes/events. The rank order of efficacy to inhibit insulin-stimulated glucose uptake was: PST-297S > PST-287K > PST-WT. The PST peptides also displayed the same order of efficacy for enhancing intracellular nitric oxide and Ca2+ levels in various cell types. In addition, PST peptides activated gluconeogenic genes in the following order: PST-297S ≈ PST-287K > PST-WT. Consistent with these in vitro results, the common PST variant allele Ser-297 was associated with significantly higher (by ∼17 mg/dl, as compared with the wild-type Gly-297 allele) plasma glucose level in our study population (n = 410). Molecular modeling and molecular dynamics simulations predicted the following rank order of α-helical content: PST-297S > PST-287K > PST-WT. Corroboratively, circular dichroism analysis of PST peptides revealed significant differences in global structures (e.g. the order of propensity to form α-helix was: PST-297S ≈ PST-287K > PST-WT). This study provides a molecular basis for enhanced potencies/efficacies of human PST variants (likely to occur in ∼300 million people worldwide) and has quantitative implications for inter-individual variations in glucose/insulin homeostasis. PMID:24338022

  14. Naturally-occurring dimers of flavonoids as anticarcinogens.

    PubMed

    Mercader, Andrew G; Pomilio, Alicia B

    2013-10-01

    Biflavonoids are dimers of flavonoid moieties linked by a C-C or C-O-C bond. Simple, complex, rearranged, natural and ketalized Diels-Alder adducts, benzofuran derivatives, and spirobiflavonoids are some of the structural groups of biflavonoids. These compounds are mainly distributed in the Gymnosperms, Angiosperms (monocots and dicots), ferns (Pteridophyta), and mosses (Bryophyta). Biflavonoids have shown a variety of biological activities, including anticancer, antibacterial, antifungal, antiviral, antiinflammatory, analgesic, antioxidant, vasorelaxant, anticlotting, among others. This work is focused on probably the most potentially relevant biological activity of biflavonoids, the anticancer activity and the involved mechanisms of action, such as induction of apoptosis [inhibition of cyclic nucleotide phosphodiesterases; effects on NF-?B family of transcription factors; activation of caspase(s); inhibition effects on bcl-2 expression, and upregulation of p53 and caspase-3 gene expression]; inhibition of angiogenesis [anti-proliferative effects; activation of Rho-GTPases and ERK signaling pathways; inhibition of FASN activity]; inhibition of pre-mRNA splicing; inhibition of human DNA topoisomerases I and II-?; anti-inflammatory/ immunoregulatory effects [inhibition of XO; inhibition of proinflammatory enzymes, such as PLA2 and COX; effects on cytokines mediated COX-2 and iNOS expression]; modulation of immune response; inhibition of protein tyrosine phosphorylation; antioxidant and analgesic activities in relation to the anticarcinogen behavior. For that reason the structures and anticarcinogenic activities of 83 biflavonoids are thoroughly discussed. The results of this work indicate that biflavonoids strongly affect the cancer cells with little effect on normal cell proliferation, suggesting a therapeutic potential against cancer. PMID:23796246

  15. Distribution of naturally occurring radionuclides (U, Th) in Timahdit black shale (Morocco).

    TOXLINE Toxicology Bibliographic Information

    Galindo C; Mougin L; Fakhi S; Nourreddine A; Lamghari A; Hannache H

    2007-01-01

    Attention has been focused recently on the use of Moroccan black oil shale as the raw material for production of a new type of adsorbent and its application to U and Th removal from contaminated wastewaters. The purpose of the present work is to provide a better understanding of the composition and structure of this shale and to determine its natural content in uranium and thorium. A black shale collected from Timahdit (Morocco) was analyzed by powder X-ray diffraction and SEM techniques. It was found that calcite, dolomite, quartz and clays constitute the main composition of the inorganic matrix. Pyrite crystals are also present. A selective leaching procedure, followed by radiochemical purification and alpha-counting, was performed to assess the distribution of naturally occurring radionuclides. Leaching results indicate that 238U, 235U, 234U, 232Th, 230Th and 228Th have multiple modes of occurrence in the shale. U is interpreted to have been concentrated under anaerobic conditions. An integrated isotopic approach showed the preferential mobilization of uranium carried by humic acids to carbonate and apatite phases. Th is partitioned between silicate minerals and pyrite.

  16. Distribution of naturally occurring radionuclides (U, Th) in Timahdit black shale (Morocco).

    PubMed

    Galindo, C; Mougin, L; Fakhi, S; Nourreddine, A; Lamghari, A; Hannache, H

    2007-01-01

    Attention has been focused recently on the use of Moroccan black oil shale as the raw material for production of a new type of adsorbent and its application to U and Th removal from contaminated wastewaters. The purpose of the present work is to provide a better understanding of the composition and structure of this shale and to determine its natural content in uranium and thorium. A black shale collected from Timahdit (Morocco) was analyzed by powder X-ray diffraction and SEM techniques. It was found that calcite, dolomite, quartz and clays constitute the main composition of the inorganic matrix. Pyrite crystals are also present. A selective leaching procedure, followed by radiochemical purification and alpha-counting, was performed to assess the distribution of naturally occurring radionuclides. Leaching results indicate that 238U, 235U, 234U, 232Th, 230Th and 228Th have multiple modes of occurrence in the shale. U is interpreted to have been concentrated under anaerobic conditions. An integrated isotopic approach showed the preferential mobilization of uranium carried by humic acids to carbonate and apatite phases. Th is partitioned between silicate minerals and pyrite. PMID:17098337

  17. Mass spectrometry and natural variations of iron isotopes.

    PubMed

    Dauphas, Nicolas; Rouxel, Olivier

    2006-01-01

    Although the processes that govern iron isotope variations in nature are just beginning to be understood, multiple studies attest of the virtue of this system to solve important problems in geosciences and biology. In this article, we review recent advances in the geochemistry, cosmochemistry, and biochemistry of iron isotopes. In Section 2, we briefly address the question of the nucleosynthesis of Fe isotopes. In Section 3, we describe the different methods for purifying Fe and analyzing its isotopic composition. The methods of SIMS, RIMS, and TIMS are presented but more weight is given to measurements by MC-ICPMS. In Section 4, the isotope anomalies measured in extraterrestrial material are briefly discussed. In Section 5, we show how high temperature processes like evaporation, condensation, diffusion, reduction, and phase partitioning can affect Fe isotopic composition. In Section 6, the various low temperature processes causing Fe isotopic fractionation are presented. These involve aqueous and biologic systems. PMID:16463281

  18. Natural abundances of carbon isotopes in acetate from a coastal marine sediment

    NASA Technical Reports Server (NTRS)

    Blair, N. E.; Martens, C. S.; Des Marais, D. J.

    1987-01-01

    Measurements of the natural abundances of carbon isotopes were made in acetate samples isolated from the anoxic marine sediment of Cape Lookout Bight, North Carolina. The typical value of the total acetate carbon isotope ratio (delta 13C) was -16.1 +/- 0.2 per mil. The methyl and carboxyl groups were determined to be -26.4 +/- 0.3 and -6.0 +/- 0.3 per mil, respectively, for one sample. The isotopic composition of the acetate is thought to have resulted from isotopic discriminations that occurred during the cycling of that molecule. Measurements of this type, which have not been made previously in the natural environment, may provide information about the dominant microbial pathways in anoxic sediments as well as the processes that influence the carbon isotopic composition of biogenic methane from many sources.

  19. Construction of a naturally occurring radioactive material project in the BeAAT hazardous waste facilities.

    PubMed

    Abuahmad, H

    2015-06-01

    This paper does not necessarily reflect the views of the International Commission on Radiological Protection. Naturally occurring radioactive material (NORM) is produced during exploration and production operations of subsidiaries of the Abu Dhabi National Oil Company (ADNOC) in the United Arab Emirates, and accumulates in drilling tubulars, plant equipment, and components. These NORM hazardous wastes need to be managed in such a way that they do not damage human health and the environment. The primary radionuclides of concern in the oil and gas industries are radium-226 and radium-228. These radioisotopes are the decay products of uranium and thorium isotopes that are present in subsurface formations from which hydrocarbons are produced. While uranium and thorium are largely immobile, radium is slightly more soluble and may become mobilised in the fluid phases of the formation (International Association of Oil & Gas Producers, 2008). In order to treat and dispose of NORM waste products safely, ADNOC's subsidiary 'TAKREER' is developing a new facility, on behalf of all ADNOC subsidiaries, within the existing Central Environmental Protection Facilities (BeAAT) in Ruwais city. The NORM plant is envisaged to treat, handle, and dispose of NORM waste in the forms of scale, sludge, and contaminated equipment. The NORM treatment facility will cover activities such as decontamination, volume reduction, NORM handling, and concrete immobilisation of NORM waste into packages for designated landfilling. PMID:25816275

  20. Mobilization of arsenic and other naturally occurring contaminants in groundwater of the Main Ethiopian Rift aquifers.

    PubMed

    Rango, Tewodros; Vengosh, Avner; Dwyer, Gary; Bianchini, Gianluca

    2013-10-01

    This study investigates the mechanisms of arsenic (As) and other naturally occurring contaminants (F(-), U, V, B, and Mo) mobilization from Quaternary sedimentary aquifers of the Main Ethiopian Rift (MER) and their enrichment in the local groundwater. The study is based on systematic measurements of major and trace elements as well as stable oxygen and hydrogen isotopes in groundwater, coupled with geochemical and mineralogical analyses of the aquifer rocks. The Rift Valley aquifer is composed of rhyolitic volcanics and Quaternary lacustrine sediments. X-ray fluorescence (XRF) results revealed that MER rhyolites (ash, tuff, pumice and ignimbrite) and sediments contain on average 72 wt. % and 65 wt. % SiO2, respectively. Petrographic studies of the rhyolites indicate predominance of volcanic glass, sanidine, pyroxene, Fe-oxides and plagioclase. The As content in the lacustrine sediments (mean = 6.6 mg/kg) was higher than that of the rhyolites (mean: 2.5 mg/kg). The lacustrine aquifers of the Ziway-Shala basin in the northern part of MER were identified as high As risk zones, where mean As concentration in groundwater was 22.4 ± 33.5 (range of 0.60-190 μg/L) and 54% of samples had As above the WHO drinking water guideline value of 10 μg/L. Field As speciation measurements showed that most of the groundwater samples contain predominantly (~80%) arsenate-As(V) over arsenite-As(III) species. The As speciation together with field data of redox potential (mean Eh = +73 ± 65 mV) and dissolved-O2 (6.6 ± 2.2 mg/L) suggest that the aquifer is predominantly oxidative. Water-rock interactions, including the dissolution of volcanic glass produces groundwater with near-neutral to alkaline pH (range 6.9-8.9), predominance of Na-HCO3 ions, and high concentration of SiO2 (mean: 85.8 ± 11.3 mg/L). The groundwater data show high positive correlation of As with Na, HCO3, U, B, V, and Mo (R(2) > 0.5; p < 0.001). Chemical modeling of the groundwater indicates that Fe-oxides and oxyhydroxides minerals were saturated in the groundwater, suggesting that the As reactivity is controlled by adsorption/desorption processes with these minerals. The data show that As and other oxyanion-forming elements such as U, B, Mo, and V had typically higher concentrations at pH > ~8, reflecting the pH-dependence of their mobilization. Based on the geochemical and stable isotope variations we have established a conceptual model for the occurrence of naturally occurring contaminants in MER groundwater: 1) regional groundwater recharge from the Highland, along the Rift margins, followed by lateral flow and water-rock interactions with the aquifer rocks resulted in a gradual increase of the salinity and naturally occurring contaminants towards the center of the valley; and (2) local δ(18)O-rich lake water recharge into adjacent shallow aquifers, followed by additional mobilization of As and other oxyanion-forming elements from the aquifer rocks. We posit that the combined physical-chemical conditions of the aquifers such as oxidizing state, Na-HCO3 composition, and pH>~8 lead to enhanced mobilization of oxyanion-forming elements from Fe-oxides and consequently contamination of local groundwater. These geochemical conditions characterize groundwater resources along the Eastern African Rift and thus constitute a potential threat to the quality of groundwater in larger areas of Eastern Africa. PMID:23899878

  1. INFLUENCE OF EASILY DEGRADABLE NATURALLY OCCURRING CARBON SUBSTRATES ON BIODEGRADATION OF MONOSUBSTITUTED PHENOLS BY AQUATIC BACTERIA

    EPA Science Inventory

    The influence of readily degradable, naturally occurring carbon substrates on the biodegradation of several monosubstitued phenols (m-cresol, m-aminophenol, p-chlorophenol) was examined. The natural substrate classes used were amino acids, carbohydrates, and fatty acids. Samples ...

  2. Long-Term Toxicity of Naturally Occurring Asbestos in Male Fischer 344 Rats

    EPA Science Inventory

    Naturally occurring asbestos (NOA) fibers are found in geologic deposits that may be disturbed by mining, earthworks, or natural processes, resulting in adverse health risks to exposed individuals. The toxicities of Libby amphibole and NOA samples including Sumas Mountain chrysot...

  3. CZ-Tope: Using Measurements of Multiple Isotopes in One Setting to Understand Critical Zone Processes Occurring over Different Timescales

    NASA Astrophysics Data System (ADS)

    Brantley, S. L.

    2014-12-01

    Critical Zone (CZ) science includes the study of the inter-related chemical, physical, and biological processes happening at the earth surface. CZ science differs from watershed science or other similar initiatives in that it not only incorporates many disciplinary approaches and crosses spatial scales, but it also aims to understand processes occurring at timescales varying from those characterizing fast chemical reactions to the slow responses of surficial systems to tectonic change. Isotope systems are an important tool that can be used to assess processes at different timescales. Some isotopic systems are used as chronometers. Synthesizing isotopic data from different elemental systems to understand processes as complex as weathering at a ridgetop, hillslope transformation, or watershed evolution is a difficult task but is essential toward deciphering the complex coupling that characterizes surficial systems. A good example where isotopes are elucidating CZ processes is the analysis of weathering at ridgetops, along hillslopes, and in watersheds. Targetting these three types of study sites at the Susquehanna Shale Hills Critical Zone Observatory, we have used Mg, Fe, Li, Ca, Be, Sr, U and other isotopes to understand the effects of weathering in one-dimension (1D), 2D and 3D, respectively. Some of the systems such as Fe yield information about elemental losses due to biogeochemical weathering. Other isotopes such as U yield information about the development of particles from bedrock. In this talk I will synthesize data from many different researchers working at the CZO to show how disparate isotopic data for one set of sites can answer questions of how landforms develop and change. This effort to use many isotopes on the same CZ setting -- which we call "CZ-tope" science -- requires sharing of sites, samples, and data in team research. CZ-tope science delineates which processes control which features at each timescale of interest.

  4. Reassessing the stable isotope composition assigned to methane flux from natural wetlands in isotope-constrained budgets

    NASA Astrophysics Data System (ADS)

    Hornibrook, Edward; Maxfield, Peter; Gauci, Vincent; Stott, Andrew

    2013-04-01

    Stable isotope ratios in CH4 preserve information about its origin and history, and are commonly used to constrain global CH4 budgets. Wetlands are key contributors to the atmospheric burden of CH4 and typically are assigned a stable carbon isotope composition of ~-60 permil in isotope-weighted stable isotope models despite the considerable range of ?13C(CH4) values (~ -100 to -40 permil) known to occur in these diverse ecosystems. Kinetic isotope effects (KIEs) associated with the metabolism of CH4-producing microorganisms generate much of the natural variation but highly negative and positive ?13C(CH4) values generally result from secondary processes (e.g., diffusive transport or oxidation by soil methanotrophs). Despite these complexities, consistent patterns exist in the isotope composition of wetland CH4 that can be linked conclusively to trophic status and consequently, natural succession or human perturbations that impact nutrient levels. Another challenge for accurate representation of wetlands in carbon cycle models is parameterisation of sporadic CH4 emission events. Abrupt release of large volumes of CH4-rich bubbles in short periods of time can account for a significant proportion of the annual CH4 flux from a wetland but such events are difficult to detect using conventional methods. New infrared spectroscopy techniques capable of high temporal resolution measurements of CH4 concentration and stable isotope composition can readily quantify short-lived CH4 pulses. Moreover, the isotope data can be used conclusively to determine shifts in the mode of CH4 transport and provide the potential to link initiation of abrupt emission events to forcing by internal or external factors.

  5. Inferring microphysical processes occurring in mesoscale convective systems from radar measurements and isotopic analysis

    NASA Astrophysics Data System (ADS)

    Narayana Rao, T.; Radhakrishna, B.; Srivastava, Rohit; Mohan Satyanarayana, T.; Narayana Rao, D.; Ramesh, R.

    2008-05-01

    An attempt has been made, for the first time, to effectively utilize the synergy of various approaches providing microphysical information of precipitation to study short term variations in a Mesoscale Convective System (MCS). A campaign has been conducted wherein rain samples are collected during the passage of MCSs over Gadanki, India, and simultaneously a powerful VHF radar and disdrometer have been operated to infer the characteristics of the vertical structure and rain drop size distribution (DSD) of precipitation. Besides the convection and transition rain, two distinctly different phases of the stratiform rain are identified. Evaporation of rain drops seems to be significant in both convection and stratiform portions of MCS. Observed changes in the temporal variation of the stable oxygen isotope ratios (δ18O) of precipitation are interpreted in terms of microphysical processes leading to isotopic fractionation. The pattern of variability in isotopic abundance is found to be different from convection to transition and to stratiform rain. The present analysis clearly shows that the height (or temperature) and the rain regime of condensation are of paramount importance in determining δ18O. Correlations of δ18O with rainfall integral parameters stress the need for caution in interpreting the depleted isotopic ratios are due to high rainfall and/or bigger drops.

  6. Transport of naturally occurring radionuclides by a seasonal tropical river, northern Australia

    NASA Astrophysics Data System (ADS)

    Murray, A. S.; Johnston, A.; Martin, P.; Hancock, G.; Marten, R.; Pfitzner, J.

    1993-09-01

    Natural radionuclide transport is used as an analogue to determine the likely fate of uranium mine effluent in a seasonal tropical river in northern Australia. Concentrations of alpha activity determined at regular intervals in both filtered and unfiltered water are presented from four sites along the sand-bed channel of the creek, and one site at the outfall of the 200 km 2 flood plain. Annual mean radium isotope concentrations were also measured. It was found that transport by the creek was conservative, in that concentrations and {226Ra}/{228Ra} ratios remained constant. About 50% of the creek load was associated with particulates. No particulate concentrations were detectable at the flood plain outfall. Alpha activity loads were calculated for the creek input and flood plain outfall. It is concluded that all the creek particulates were trapped by the flood plain, probably at the upstream end. A substantial fraction of the solute/colloidal load was also retained. A 50% decrease in the {226Ra}/{228Ra} ratio between the input and outfall supports this conclusion. Systematic errors arising from sampling are considered by examining the 226Ra concentrations in detail through a flood at one creek site, and it is concluded that such errors are negligible. Previous modelling had assumed that only 20% of released activity would be retained on the flood plain. It is now recommended that complete retention should be assumed, with deposition occurring preferentially at the upstream end of the flood plain. This will have the effect of increasing the predicted radiation dose to members of the public by more than a factor of five.

  7. A century of oil and gas exploration in Albania: assessment of Naturally Occurring Radioactive Materials (NORMs).

    PubMed

    Xhixha, G; Baldoncini, M; Callegari, I; Colonna, T; Hasani, F; Mantovani, F; Shala, F; Strati, V; Xhixha Kaçeli, M

    2015-11-01

    The Naturally Occurring Radioactive Materials (NORMs) that are potentially generated from oil and gas extractions in Albania have been disposed of without regulations for many decades, and therefore, an extensive survey in one of the most productive regions (Vlora-Elbasan) was performed. A total of 52 gamma ray spectrometry measurements of soil, oil-sand, sludge, produced water and crude oil samples were performed. We discovered that relatively low activity concentrations of (226)Ra, (228)Ra, (228)Th and (40)K, with concentrations of 23±2Bq/kg, 23±2Bq/kg, 24±3Bq/kg and 549±12Bq/kg, respectively, came from the oil-sands produced by the hydrocarbon extraction of the molasses formations. The mineralogical characterizations and the (228)Ra/(40)K and (226)Ra/(40)K ratios of these Neogene deposits confirmed the predictions of the geological and geodynamic models of a dismantling of the Mesozoic source rocks. The average activity concentrations (±standard deviations) of the radium isotopes ((226)Ra and (228)Ra) and of the (228)Th and (40)K radionuclides in soil samples were 20±5Bq/kg, 25±10Bq/kg, 25±9Bq/kg and 326±83Bq/kg, respectively. Based on the measurements in this study, the future radiological assessments of other fields in the region should be strategically planned to focus on the oil-sands from the molasses sediments. Disequilibrium in the (228)Ra decay segment was not observed in the soil, sludge or oil-sand samples within the standard uncertainties. After a detailed radiological characterization of the four primary oil fields, we concluded that the outdoor absorbed dose rate never exceeded the worldwide population weighted average absorbed dose rate in outdoor air from terrestrial gamma radiation. PMID:26037957

  8. Isotope fractionation during natural gas hydrate formation

    NASA Astrophysics Data System (ADS)

    Nesheim Vaular, Espen; Corak, Djurdjica; Barth, Tanja

    2010-05-01

    In the task of pursuing the origin of hydrate-bound gas, isotope analysis is a well established tool of prediction. The carbon isotope values of methane, ethane, propane and i-butane will strongly indicate the source to either be microbial, thermogenic or of mixed origin. This is due to kinetic fractionation during microbial activity. In microbial CO2 reduction, the microbes tend to reduce δ12C molecules preferentially to δ13C. This leads to light methane and ethane in the gas from microbial activity compared to methane and ethane of thermogenic origin. Recently, isotopically light methane and ethane from hydrate-bond gas from the pockmark field of Nyegga (Norwegian Sea) has been reported. The gas has migrated from a free gas system beneath the base of gas hydrate stability and reached the seafloor through a chimney structured migration feature. The free gas layer is thought to be supported by deeper sources, and polygonal faulting that is known to lay on top of petroleum reservoirs supports speculations that the free gas layer contains thermogenic gas. The isotopic evidence classifies the hydrate gas as fractionated by microbial activity, while the composition and geological setting tell tales of a thermogenic source. This conundrum has led to the speculation upon a fractionation of carbon isotope through hydrate formation. With an experimental setup consisting of a cooling incubator and a pressure cell with controlled torque stirring, hydrates can form under controlled pressure and temperature conditions. The gas hydrates are formed with excess of gas making it possible to sample both the excess gas and hydrate gas. The gas is 99.5 % methane,

  9. DECIPHERING NATURALLY-OCCURRING PB CONTAMINATION IMPACTING DRINKING WATER WELLS: SHAKER VILLAGE CATCHMENT, MAINE.

    EPA Science Inventory

    Trace Pb concentrations in groundwater within glacial deposits across Maine fluctuate considerably. Deciphering the distribution and sources of naturally occurring Pb in groundwater with only the use of conventional anomaly identification techniques presents a challenge. In a rep...

  10. Environmental and biomedical applications of natural metal stable isotope variations

    USGS Publications Warehouse

    Bullen, T.D.; Walczyk, T.

    2009-01-01

    etal stable isotopes are now being used to trace metal contaminants in the environment and as indicators of human systemic function where metals play a role. Stable isotope abundance variations provide information about metal sources and the processes affecting metals in complex natural systems, complementing information gained from surrogate tracers, such as metal abundance ratios or biochemical markers of metal metabolism. The science is still in its infancy, but the results of initial studies confirm that metal stable isotopes can provide a powerful tool for forensic and biomedical investigations.

  11. Stable isotope tracers: natural and anthropogenic recharge, Orange County, California

    NASA Astrophysics Data System (ADS)

    Williams, Alan E.

    1997-12-01

    Stable isotopic techniques have been utilized to locate occurrences and trace movements of a variety of naturally and anthropogenically recharged waters in aquifers of Orange County, California. This basin is of particular interest not only because it provides the dominant water supply for the two million residents of this well-populated county, but also because it is representative of a common arid environment where natural recharge is dominated by distant, high-elevation precipitation transported by a major river. Such arid basins are particularly sensitive to climatic and anthropogenic disturbance of their recharge and their subsurface hydrology. In order to identify distinctive waters, oxygen and hydrogen stable isotope ratios from Orange County wells have been compared with a regional database including an array of surface water samples representative of watershed runoff. Four distinctive subsurface water types can be resolved. Waters of "local" rainfall and imported, "Colorado" River aqueduct origins are easily distinguished from dominant, "native" Santa Ana river compositions by use of hydrogen and oxygen stable isotope analysis. Recent human interference with Santa Ana river flow and recharge is also marginally resolvable by isotopic techniques. Distinguishable isotopic signatures of "recent" Santa Ana recharge appear to be due to evaporative loss, perhaps during storage in the Prado Reservoir or in percolation ponds, prior to recharge into Orange County aquifers. Characterization of traceable isotopic signatures of distinct natural and anthropogenic recharge components provides a major advance towards use of such techniques for developing a well constrained, three-dimensional hydrologic model for this complex basin.

  12. Survival of naturally occurring Campylobacter in refrigerated and frozen rinsate from a broiler carcass

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to determine if naturally occurring Campylobacter in a broiler rinsate could survive in cold storage. Ten commercial broiler carcasses were each rinsed with 500 ml of Butterfield’s buffer and all carcasses tested positive for the presence of 104-105/ml naturally occu...

  13. Concentrations of the naturally occurring radionucleides Pb-210, Po-210, and Ra-226 in aquatic fauna

    NASA Technical Reports Server (NTRS)

    Holtzman, R. B.

    1969-01-01

    Study reveals naturally occurring radionuclides are ubiquitous and contribute a substantial fraction of the natural radiation dose to humans and various biota. Measurements may be useful in ecological and other biological problems such as tracing food chains of animals and study of the metabolism of these elements.

  14. Mass fractionation of noble gases in synthetic methane hydrate: Implications for naturally occurring gas hydrate dissociation

    USGS Publications Warehouse

    Hunt, Andrew G.; Stern, Laura; Pohlman, John W.; Ruppel, Carolyn; Moscati, Richard J.; Landis, Gary P.

    2013-01-01

    As a consequence of contemporary or longer term (since 15 ka) climate warming, gas hydrates in some settings may presently be dissociating and releasing methane and other gases to the ocean-atmosphere system. A key challenge in assessing the impact of dissociating gas hydrates on global atmospheric methane is the lack of a technique able to distinguish between methane recently released from gas hydrates and methane emitted from leaky thermogenic reservoirs, shallow sediments (some newly thawed), coal beds, and other sources. Carbon and deuterium stable isotopic fractionation during methane formation provides a first-order constraint on the processes (microbial or thermogenic) of methane generation. However, because gas hydrate formation and dissociation do not cause significant isotopic fractionation, a stable isotope-based hydrate-source determination is not possible. Here, we investigate patterns of mass-dependent noble gas fractionation within the gas hydrate lattice to fingerprint methane released from gas hydrates. Starting with synthetic gas hydrate formed under laboratory conditions, we document complex noble gas fractionation patterns in the gases liberated during dissociation and explore the effects of aging and storage (e.g., in liquid nitrogen), as well as sampling and preservation procedures. The laboratory results confirm a unique noble gas fractionation pattern for gas hydrates, one that shows promise in evaluating modern natural gas seeps for a signature associated with gas hydrate dissociation.

  15. Mass transfer and carbon isotope evolution in natural water systems

    USGS Publications Warehouse

    Wigley, T.M.L.; Plummer, L.N.; Pearson, F.J., Jr.

    1978-01-01

    This paper presents a theoretical treatment of the evolution of the carbon isotopes C13 and C14 in natural waters and in precipitates which derive from such waters. The effects of an arbitrary number of sources (such as dissolution of carbonate minerals and oxidation of organic material) and sinks (such as mineral precipitation, CO2 degassing and production of methane), and of equilibrium fractionation between solid, gas and aqueous phases are considered. The results are expressed as equations relating changes in isotopic composition to changes in conventional carbonate chemistry. One implication of the equations is that the isotopic composition of an aqueous phase may approach a limiting value whenever there are simultaneous inputs and outputs of carbonate. In order to unambiguously interpret isotopic data from carbonate precipitates and identify reactants and products in reacting natural waters, it is essential that isotopic changes are determined chiefly by reactant and product stoichiometry, independent of reaction path. We demonstrate that this is so by means of quantitative examples. The evolution equations are applied to: 1. (1) carbon-14 dating of groundwaters; 2. (2) interpretation of the isotopic composition of carbonate precipitates, carbonate cements and diagenetically altered carbonates; and 3. (3) the identification of chemical reaction stoichiometry. These applications are illustrated by examples which show the variation of ??C13 in solutions and in precipitates formed under a variety of conditions involving incongruent dissolution, CO2 degassing, methane production and mineral precipitation. ?? 1978.

  16. Recent Advances in the Chemistry and Biology of Naturally Occurring Antibiotics

    PubMed Central

    Chen, Jason S.; Edmonds, David J.; Estrada, Anthony A.

    2009-01-01

    Lead-in Ever since the world-shaping discovery of penicillin, natures molecular diversity has been extensively screened for new medications and lead compounds in drug discovery. The search for anti-infective agents intended to combat infectious diseases has been of particular interest and has enjoyed a high degree of success. Indeed, the history of antibiotics is marked with impressive discoveries and drug development stories, the overwhelming majority of which have their origins in nature. Chemistry, and in particular chemical synthesis, has played a major role in bringing naturally occurring antibiotics and their derivatives to the clinic, and no doubt these disciplines will continue to be key enabling technologies for future developments in the field. In this review article, we highlight a number of recent discoveries and advances in the chemistry, biology, and medicine of naturally occurring antibiotics, with particular emphasis on the total synthesis, analog design, and biological evaluation of molecules with novel mechanisms of action. PMID:19130444

  17. Ability of orally administered IFN-?4 to inhibit naturally occurring gingival inflammation in dogs.

    PubMed

    Ito, Akira; Isogai, Emiko; Yoshioka, Kuniaki; Sato, Ko; Himeno, Naomi; Gotanda, Toru

    2010-09-01

    It has been reported that type I interferons (IFN-?/?) play an important role in innate immune responses against viral and bacterial infections. In this study, we used and examined naturally occurred canine periodontal disease to show the therapeutic efficacy of low dose oral administration (LDOA) of canine IFN-? subtype 4 (CaIFN-?4). We administered purified recombinant CaIFN-?4 expressed in a baculovirus system to dogs with or without gingival inflammation. We found that LDOA of CaIFN-?4 reduce periodontopathic bacterial counts. LDOA induced improvement of naturally occurring gingival inflammation, and reduction of the stress marker responses was also observed after LDOA. These results suggest that LDOA of CaIFN-?4 has effectiveness for improvement of naturally occurring gingival inflammation in dogs. PMID:20424396

  18. Chlorine isotope investigation of natural attenuation of trichloroethene in an aerobic aquifer

    SciTech Connect

    Sturchio, N.C.; Heraty, L.J.; Huang, L.; Holt, B.D.; Abrajano, T.A. Jr.; Clausen, J.L.

    1998-10-15

    Natural attenuation of chlorinated aliphatic hydrocarbons (CAHs) can be an important mechanism for groundwater remediation. It is difficult to determine the effectiveness of natural CAH attenuation from chemical analyses of groundwater samples because mixing, dispersion, and secondary reactions can mask the chemical evidence of attenuation. In this paper, the authors explore the application of stable chlorine isotope ratio measurements as a new tool for evaluating natural attenuation of CAHs. They report stable isotope ratios of chlorine in both trichloroethene (TCE) and inorganic chloride in groundwater from an aerobic aquifer beneath an extensively contaminated industrial site, the Paducah Gaseous Diffusion Plant in western Kentucky. Variations in the concentrations and chlorine isotope ratios of TCE and chloride in the groundwater are consistent with those expected from natural attenuation. These data support a model in which partial TCE degradation occurred in relatively impermeable, clay-rich sediments above the aquifer, and little or no further degradation of TCE occurred within the aquifer. A record of changing conditions within the TCE source area can be inferred from the spatial variation of chlorine isotope ratios for TCE and chloride within the plume.

  19. Chemical constituents of peppers (Piper spp.) and application to food preservation: naturally occurring antioxidative compounds.

    PubMed

    Nakatani, N; Inatani, R; Ohta, H; Nishioka, A

    1986-08-01

    In a structure analysis of the compounds of the genus Piper (Family Piperaceae), we identified five phenolic amides from Piper nigrum, seven compounds from P. retrofractum, and two compounds from P. baccatum. All the phenolic amides possess significant antioxidant activities that are more effective than the naturally occurring antioxidant, alpha-tocopherol. One amide, feruperine, has antioxidant activity as high as the synthetic antioxidants, butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT). Naturally occurring antioxidants, therefore, may surpass BHA and BHT in their ability to inactivate mutagens in food. PMID:3757949

  20. Apoptosis and autophagy induction as mechanism of cancer prevention by naturally occurring dietary agents

    PubMed Central

    Mukhtar, Eiman; Adhami, Vaqar Mustafa; Khan, Naghma; Mukhtar, Hasan

    2013-01-01

    Nontoxic naturally occurring compounds, especially those from dietary sources, are receiving increasing consideration for prevention and treatment of diseases including cancer. There is a growing need for innovative anticancer therapies and therefore search for natural compounds with novel biological activities or antineoplastic potential is currently an important area in drug discovery. Support for this interest also comes from increasing concern over the efficacy and safety of many conventional therapies, especially those that run over a long course of time. Laboratory studies in different in vitro and in vivo systems have shown that many natural compounds possess the capacity to regulate response to oxidative stress and DNA damage, suppress angiogenesis, inhibit cell proliferation and induce autophagy and apoptosis. This review discusses the induction of apoptosis and autophagy as a mechanism of cancer prevention by some of the most studied naturally occurring dietary compounds. PMID:23140293

  1. Recent progress regarding the bioactivities, biosynthesis and synthesis of naturally occurring resorcinolic macrolides.

    PubMed

    Xu, Jing; Jiang, Cheng-shi; Zhang, Zai-long; Ma, Wen-quan; Guo, Yue-wei

    2014-03-01

    Macrolides, which comprise a family of lactones with different ring sizes, belong to the polyketide class of natural products. Resorcinolic macrolides, an important subgroup, possess interesting structures and exhibit a wide variety of bioactivities, such as anti-tumor, anti-bacteria, and anti-malaria activities, etc. This review summarizes progress in isolation, bioactivity studies, biosynthesis, and representative chemical syntheses of this group of macrolides in recent decades, encompassing 63 naturally occurring macrolides published in 120 articles. PMID:24464049

  2. A study of the dry heat resistance of naturally occurring organisms widely dispersed on a surface

    NASA Technical Reports Server (NTRS)

    Garst, D. M.; Lindell, K. F.

    1971-01-01

    Although Bacillus subtilis var. niger is the standard test organism for NASA planetary quarantine sterilization studies, it was found that some naturally occurring soil organisms are more heat resistant. The separation of these organisms from soil particles is described. Experiments are discussed which were designed to show that the heat resistance is a natural characteristic of the organisms, rather than a condition induced by the clumping effect of agglomerated particles and organisms.

  3. Recent progress regarding the bioactivities, biosynthesis and synthesis of naturally occurring resorcinolic macrolides

    PubMed Central

    Xu, Jing; Jiang, Cheng-shi; Zhang, Zai-long; Ma, Wen-quan; Guo, Yue-wei

    2014-01-01

    Macrolides, which comprise a family of lactones with different ring sizes, belong to the polyketide class of natural products. Resorcinolic macrolides, an important subgroup, possess interesting structures and exhibit a wide variety of bioactivities, such as anti-tumor, anti-bacteria, and anti-malaria activities, etc. This review summarizes progress in isolation, bioactivity studies, biosynthesis, and representative chemical syntheses of this group of macrolides in recent decades, encompassing 63 naturally occurring macrolides published in 120 articles. PMID:24464049

  4. A naturally occurring brominated furanone covalently modifies and inactivates LuxS.

    PubMed

    Zang, Tianzhu; Lee, Bobby W K; Cannon, Lisa M; Ritter, Kathryn A; Dai, Shujia; Ren, Dacheng; Wood, Thomas K; Zhou, Zhaohui Sunny

    2009-11-01

    Halogenated furanones, a group of natural products initially isolated from marine red algae, are known to inhibit bacterial biofilm formation, swarming, and quorum sensing. However, their molecular targets and the precise mode of action remain elusive. Herein, we show that a naturally occurring brominated furanone covalently modifies and inactivates LuxS (S-ribosylhomocysteine lyase, EC 4.4.1.21), the enzyme which produces autoinducer-2 (AI-2). PMID:19775890

  5. MALDI-TOF Mass Spectrometry of Naturally-Occurring Mixtures of Mono- and Di-rhamnolipids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been developed for high-throughput screening of naturally-occurring mixtures of rhamnolipids from Pseudomonas spp. Mono- and di-rhamnolipids are readily distinguished by characteristic molecular adduct i...

  6. Comparison of Selective Campylobacter Media for Detection and Enumeration of Naturally Occurring Campylobacter spp. on Poultry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Campylobacter spp. are among the most common cause of bacterial foodborne diarrheal illness; poultry has been linked as a primary source of contamination. Detection and enumeration of low numbers of naturally occurring Campylobacter spp. on poultry is difficult due to the presence of competing micro...

  7. Therapeutic Recreation in the Naturally Occurring Retirement Community (NORC): Benefitting "Aging in Place."

    ERIC Educational Resources Information Center

    Kunstler, Robin

    2002-01-01

    Describes how therapeutic recreation in naturally occurring retirement communities (neighborhoods where most residents are older) can promote healthy lifestyles, presenting a case report of an in-home therapeutic recreation program offered in conjunction with nursing and social services in a such a community and discussing implications for…

  8. Naturally occurring vapor-liquid-solid (VLS) Whisker growth of germanium sulfide

    USGS Publications Warehouse

    Finkelman, R.B.; Larson, R.R.; Dwornik, E.J.

    1974-01-01

    The first naturally occurring terrestrial example of vapor-liquid-solid (VLS) growth has been observed in condensates from gases released by burning coal in culm banks. Scanning electron microscopy, X-ray diffraction, and energy dispersive analysis indicate that the crystals consist of elongated rods (??? 100 ??m) of germanium sulfide capped by bulbs depleted in germanium. ?? 1974.

  9. Naturally occurring reverse tilt domains in a high-pretilt alignment nematic liquid crystal

    NASA Astrophysics Data System (ADS)

    Wang, Ruiting; Atherton, Timothy J.; Zhu, Minhua; Petschek, Rolfe G.; Rosenblatt, Charles

    2007-08-01

    A cell whose substrates were coated with the polyamic acid SE1211 (Nissan Chemical Industries) and baked at high temperatures was filled with a nematic liquid crystal in the isotropic phase. On cooling into the nematic phase, naturally occurring and temporally and thermally robust reverse tilt domains separated by thin filamentlike walls were observed. The properties of these structures are reported.

  10. REMOVAL OF ARSENIC FROM GROUNDWATER USING NATURALLY OCCURRING IRON OXIDES IN RURAL REGIONS OF MONGOLIA

    EPA Science Inventory

    We have found that the iron oxide particles produced by grinding naturally occurring iron ores are very effective in removing arsenic from water. The arsenic adsorption isothermal of the particles h...

  11. THE ISOLATION AND CHARACTERIZATION OF NATURALLY-OCCURRING AMOEBA-RESISTANT BACTERIA FROM WATER SAMPLES

    EPA Science Inventory

    A. Isolation of ARB from naturally-occurring amoebae and identification based on 16S rDNA sequencing.

    Does Naturally Occurring Comprehension Strategies Instruction Make a Difference when Students Read Expository Text?

    ERIC Educational Resources Information Center

    Braten, Ivar; Anmarkrud, Oistein

    2013-01-01

    The present study examined whether observed differences in naturally occurring classroom instruction of reading comprehension strategies were reflected in students' independent use of strategies to comprehend expository text. Based on a descriptive classroom study in 4 ninth-grade language arts classrooms, participants were divided into two groups

  12. Subject Reaction to Human-Caused and Naturally-Occurring Radioactive Threat.

    ERIC Educational Resources Information Center

    Belford, Susan; Gibbs, Margaret

    While research has shown that people are adversely psychologically affected by knowledge that their communities have been toxically contaminated, it has been suggested that those who see a disaster as naturally occurring tend to be less adversely affected than those who see a disaster as caused by human acts. To examine this issue, questionnaires…

  13. Photoprotection: part I. Photoprotection by naturally occurring, physical, and systemic agents.

    PubMed

    Jansen, Rebecca; Wang, Steven Q; Burnett, Mark; Osterwalder, Uli; Lim, Henry W

    2013-12-01

    The acute and chronic consequences of ultraviolet radiation on human skin are reviewed. An awareness of variations in naturally occurring photoprotective agents and the use of glass, sunglasses, and fabric can lead to effective protection from the deleterious effects of ultraviolet radiation. New systemic agents, including Polypodium leucotomos, afamelanotide, and antioxidants have potential as photoprotective agents. PMID:24238179

  14. Antibacterial Activities of Naturally occurring Compounds against Mycobacterium avium subspecies paratuberculosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antibacterial activities of 19 naturally-occurring compounds (including essential oils and some of their isolated constituents, apple and green tea polyphenols and other plant extracts) against three strains of Mycobacterium avium subspecies paratuberculosis (Map), a bovine isolate NCTC 8578, a raw ...

  15. Comparison of selective media for detection and enumeration of naturally occurring Campylobacter spp. on poultry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: Campylobacter spp. are known to be among the most common bacteria to cause diarrheal illness, with poultry being linked as the primary source of contamination related to foodborne illness. Enumeration and detection of low numbers of naturally occurring Campylobacter spp. on poultry pro...

  16. Radiological dose assessment related to management of naturally occurring radioactive materials generated by the petroleum industry

    SciTech Connect

    Smith, K.P.; Blunt, D.L.; Williams, G.P.; Tebes, C.L.

    1995-05-01

    A preliminary radiological dose assessment related to equipment decontamination, subsurface disposal, landspreading, equipment smelting, and equipment burial was conducted to address concerns regarding the presence of naturally occurring radioactive materials in production waste streams. The assessment evaluated the relative dose of these activities and included a sensitivity analysis of certain input parameters. Future studies and potential policy actions are recommended.

  17. Fundamental studies on kinetic isotope effect (KIE) of hydrogen isotope fractionation in natural gas systems

    NASA Astrophysics Data System (ADS)

    Ni, Yunyan; Ma, Qisheng; Ellis, Geoffrey S.; Dai, Jinxing; Katz, Barry; Zhang, Shuichang; Tang, Yongchun

    2011-05-01

    Based on quantum chemistry calculations for normal octane homolytic cracking, a kinetic hydrogen isotope fractionation model for methane, ethane, and propane formation is proposed. The activation energy differences between D-substitute and non-substituted methane, ethane, and propane are 318.6, 281.7, and 280.2 cal/mol, respectively. In order to determine the effect of the entropy contribution for hydrogen isotopic substitution, a transition state for ethane bond rupture was determined based on density function theory (DFT) calculations. The kinetic isotope effect (KIE) associated with bond rupture in D and H substituted ethane results in a frequency factor ratio of 1.07. Based on the proposed mathematical model of hydrogen isotope fractionation, one can potentially quantify natural gas thermal maturity from measured hydrogen isotope values. Calculated gas maturity values determined by the proposed mathematical model using ?D values in ethane from several basins in the world are in close agreement with similar predictions based on the ? 13C composition of ethane. However, gas maturity values calculated from field data of methane and propane using both hydrogen and carbon kinetic isotopic models do not agree as closely. It is possible that ?D values in methane may be affected by microbial mixing and that propane values might be more susceptible to hydrogen exchange with water or to analytical errors. Although the model used in this study is quite preliminary, the results demonstrate that kinetic isotope fractionation effects in hydrogen may be useful in quantitative models of natural gas generation, and that ?D values in ethane might be more suitable for modeling than comparable values in methane and propane.

  18. Fundamental studies on kinetic isotope effect (KIE) of hydrogen isotope fractionation in natural gas systems

    USGS Publications Warehouse

    Ni, Y.; Ma, Q.; Ellis, G.S.; Dai, J.; Katz, B.; Zhang, S.; Tang, Y.

    2011-01-01

    Based on quantum chemistry calculations for normal octane homolytic cracking, a kinetic hydrogen isotope fractionation model for methane, ethane, and propane formation is proposed. The activation energy differences between D-substitute and non-substituted methane, ethane, and propane are 318.6, 281.7, and 280.2cal/mol, respectively. In order to determine the effect of the entropy contribution for hydrogen isotopic substitution, a transition state for ethane bond rupture was determined based on density function theory (DFT) calculations. The kinetic isotope effect (KIE) associated with bond rupture in D and H substituted ethane results in a frequency factor ratio of 1.07. Based on the proposed mathematical model of hydrogen isotope fractionation, one can potentially quantify natural gas thermal maturity from measured hydrogen isotope values. Calculated gas maturity values determined by the proposed mathematical model using ??D values in ethane from several basins in the world are in close agreement with similar predictions based on the ??13C composition of ethane. However, gas maturity values calculated from field data of methane and propane using both hydrogen and carbon kinetic isotopic models do not agree as closely. It is possible that ??D values in methane may be affected by microbial mixing and that propane values might be more susceptible to hydrogen exchange with water or to analytical errors. Although the model used in this study is quite preliminary, the results demonstrate that kinetic isotope fractionation effects in hydrogen may be useful in quantitative models of natural gas generation, and that ??D values in ethane might be more suitable for modeling than comparable values in methane and propane. ?? 2011 Elsevier Ltd.

  19. Stratigraphic and geochemical controls on naturally occurring arsenic in groundwater, eastern Wisconsin, USA

    NASA Astrophysics Data System (ADS)

    Schreiber, M. E.; Simo, J. A.; Freiberg, P. G.

    High arsenic concentrations (up to 12,000μg/L) have been measured in groundwater from a confined sandstone aquifer in eastern Wisconsin. The main arsenic source is a sulfide-bearing secondary cement horizon (SCH) that has variable thickness, morphology, and arsenic concentrations. Arsenic occurs in pyrite and marcasite as well as in iron oxyhydroxides but not as a separate arsenopyrite phase. Nearly identical sulfur isotopic signatures in pyrite and dissolved sulfate and the correlation between dissolved sulfate, iron, and arsenic concentrations suggest that sulfide oxidation is the dominant process controlling arsenic release to groundwater. However, arsenic-bearing oxyhydroxides can potentially provide another arsenic source if reducing conditions develop or if they are transported as colloids in the aquifer. Analysis of well data indicates that the intersection of the SCH with static water levels measured in residential wells is strongly correlated with high concentrations of arsenic in groundwater. Field and laboratory data suggest that the most severe arsenic contamination is caused by localized borehole interactions of air, water, and sulfides. Although arsenic contamination is caused by oxidation of naturally occurring sulfides, it is influenced by water-level fluctuations caused by municipal well pumping or climate changes, which can shift geographic areas in which contamination occurs. Résumé De fortes concentrations en arsenic, jusqu'à 12000μg/L, ont été mesurées dans l'eau souterraine d'un aquifère gréseux captif, dans l'est du Wisconsin. La principale source d'arsenic est un horizon à cimentation secondaire (SCH) comportant des sulfures, dont l'épaisseur, la morphologie et les concentrations en arsenic sont variables. L'arsenic est présent dans la pyrite et dans la marcassite, de même que dans des oxy-hydroxydes de fer, mais non pas dans une phase séparée d'arsénopyrite. Les signatures isotopiques du soufre presque identiques dans la pyrite et dans les sulfates dissous et la corrélation entre les concentrations en sulfates, en fer et en arsenic dissous laissent penser que l'oxydation des sulfures est le processus dominant contrôlant la libération de l'arsenic dans les eaux souterraines. Cependant, les oxy-hydroxydes contenant de l'arsenic sont susceptibles d'être une autre source d'arsenic si des conditions réductrices apparaissent ou s'ils sont transportés dans l'aquifère sous forme de colloïdes. L'analyse des données provenant de puits montre que l'intersection entre le SCH et les niveaux statiques des puits domestiques est fortement corrélée à de fortes concentrations en arsenic dans les eaux souterraines. Des données de terrain et de laboratoire conduisent à penser que la contamination en arsenic la plus forte est causée par l'interaction localisée aux forages entre l'air, l'eau et les sulfures. Bien que la contamination en arsenic soit causée par l'oxydation de sulfures présents naturellement, elle est influencée par les fluctuations du niveau piézométrique causées par les pompages du captage municipal ou par les variations climatiques, ce qui peut conduire au déplacement des zones géographiques où se produisent les contaminations. Resumen Se han medido concentraciones de arsénico muy altas (de hasta 12000μg/L) en las aguas subterráneas de un acuífero confinado, en areniscas, localizado en la parte oriental de Wisconsin (EEUU). La fuente principal de arsénico es un horizonte de cementación secundaria (SCH) con un alto contenido en sulfuros, y con una gran variabilidad en espesor, morfología y concentraciones de As. El arsénico aparece en piritas y marcasitas, además de en oxihidróxidos de hierro, pero no como una fase independiente de arsenopiritas. El hecho que la marca isotópica de piritas y sulfatos disueltos sea muy similar, y que exista una gran correlación entre las concentraciones de sulfato disuelto, hierro y arsénico sugiere que la oxidación de sulfuros es el proceso que controla la aportación de arsénico al agua subterránea. Sin embargo, los oxihidróxidos con alto contenido en arsénico podrían suponer otra fuente de arsénico si se llegaran a desarrollar condiciones reductoras o si se transportaran como coloides por el acuífero. De los datos procedentes de pozos, se ve una fuerte correlación entre la presencia de altas concentraciones de As en el agua y que el nivel freático intersecte el SCH. Los datos de campo y de laboratorio indican que los puntos con mayor contaminación de arsénico son debidos a interacciones de carácter local y en los propios pozos entre aire, agua y sulfuros. Aunque la contaminación por As está causada por la oxidación de sulfuros presentes de manera natural, también está muy influenciada por las fluctuaciones en los niveles freáticos causadas por bombeos o cambios climáticos.

  1. Hh signaling inhibitors from Vitex negundo; naturally occurring inhibitors of the GLI1-DNA complex.

    PubMed

    Arai, Midori A; Fujimatsu, Teruhisa; Uchida, Kyoko; Sadhu, Samir K; Ahmed, Firoj; Ishibashi, Masami

    2013-05-01

    The hedgehog (Hh) signaling pathway has crucial roles in embryonic development, cell maintenance and proliferation, and is also known to contribute to cancer cell growth. New naturally occurring Hh inhibitors (1, 7 and 9) were isolated from Vitex negundo using our previously constructed cell-based assay. Bioactivity guided isolation provided 9 natural compounds including a new diterpene, nishindanol (9). Compounds 7 and 9 showed cytotoxicity against cancer cell lines in which Hh signaling was aberrantly activated. Vitetrifolin D (7; GLI1 transcriptional inhibition IC50 = 20.2 ?M) showed inhibition of Hh related protein (PTCH and BCL2) production. Interestingly, the constructed electrophoresis mobility shift assay revealed that vitetrifolin D (7) disrupted GLI1 binding on its DNA binding domain. epi-Sclareol (8; inactive), possessing a similar structure to 7, did not show inhibition of GLI1DNA complex formation. This is the first example of naturally occurring inhibitors of GLI1DNA complex formation. PMID:23403897

  2. Groundwater surface water interaction study using natural isotopes tracer

    NASA Astrophysics Data System (ADS)

    Yoon, Yoon Yeol; Kim, Yong Chul; Cho, Soo Young; Lee, Kil Yong

    2015-04-01

    Tritium and stable isotopes are a component of the water molecule, they are the most conservative tracer for groundwater study. And also, radon is natural radioactive nuclide and well dissolved in groundwater. Therefore, these isotopes are used natural tracer for the study of surface water and groundwater interaction of water curtain greenhouse area. The study area used groundwater as a water curtain for warming tool of greenhouse during the winter, and is associated with issues of groundwater shortage while being subject to groundwater-river water interaction. During the winter time, these interactions were studied by using Rn-222, stable isotopes and H-3. These interaction was monitored in multi depth well and linear direction well of groundwater flow. And dam effect was also compared. Samples were collected monthly from October 2013 to April 2014. Radon and tritium were analyzed using Quantulus low background liquid scintillation counter and stable isotopes were analyzed using an IRIS (Isotope Ratio Infrared Spectroscopy ; L2120-i, Picarro). During the winter time, radon concentration was varied from 0.07 Bq/L to 8.9 Bq/L and different interaction was showed between dam. Surface water intrusion was severe at February and restored April when greenhouse warming was ended. The stable isotope results showed different trend with depth and ranged from -9.16 to -7.24 for ? 18O value, while the ?D value was ranged from -57.86 to -50.98 . The groundwater age as dated by H-3 was ranged 0.23 Bq/L - 0.59 Bq/L with an average value of 0.37 Bq/L.

  3. Natural Radionuclides and Isotopic Signatures for Determining Carbonaceous Aerosol Sources, Aerosol Lifetimes, and Washout Processes

    SciTech Connect

    Gaffney, Jeffrey

    2012-12-12

    This is the final technical report. The project description is as follows: to determine the role of aerosol radiative forcing on climate, the processes that control their atmospheric concentrations must be understood, and aerosol sources need to be determined for mitigation. Measurements of naturally occurring radionuclides and stable isotopic signatures allow the sources, removal and transport processes, as well as atmospheric lifetimes of fine carbonaceous aerosols, to be evaluated.

  4. Interaction of flavonoids, the naturally occurring antioxidants with different media: A UV-visible spectroscopic study

    NASA Astrophysics Data System (ADS)

    Naseem, Bushra; Shah, S. W. H.; Hasan, Aurangzeb; Sakhawat Shah, S.

    2010-04-01

    Quantitative parameters for interaction of flavonoids—the naturally occurring antioxidants, with solvents and surfactants are determined using UV-visible absorption spectroscopy. The availability of flavonoids; kaempferol, apigenin, kaempferide and rhamnetin in micelles of sodium dodecyl sulfate (SDS) is reflected in terms of partition coefficient, Kc. Thermodynamic calculations show that the process of transfer of flavonoid molecules to anionic micelles of SDS is energy efficient. A distortion in flavonoid's morphology occurs in case of kaempferol and apigenin in surfactant and water, exhibited in terms of a new band in the UV region of electronic spectra of these flavonoids. The partition coefficients of structurally related flavonoids are correlated with their antioxidant activities.

  5. Is it necessary to raise awareness about technologically enhanced naturally occurring radioactive materials?

    PubMed

    Michalik, Bogus?aw

    2009-10-01

    Since radiation risks are usually considered to be related to nuclear energy, the majority of research on radiation protection has focused on artificial radionuclides in radioactive wastes, spent nuclear fuel or global fallout caused by A-bomb tests and nuclear power plant failures. Far less attention has been paid to the radiation risk caused by exposure to ionizing radiation originating from natural radioactivity enhanced due to human activity, despite the fact that technologically enhanced naturally occurring radioactive materials are common in many branches of the non-nuclear industry. They differ significantly from "classical" nuclear materials and usually look like other industrial waste. The derived radiation risk is usually associated with risk caused by other pollutants and can not be controlled by applying rules designed for pure radioactive waste. Existing data have pointed out a strong need to take into account the non-nuclear industry where materials containing enhanced natural radioactivity occur as a special case of radiation risk and enclose them in the frame of the formal control. But up to now there are no reasonable and clear regulations in this matter. As a result, the non-nuclear industries of concern are not aware of problems connected with natural radioactivity or they would expect negative consequences in the case of implementing radiation protection measures. The modification of widely comprehended environmental legislation with requirements taken from radiation protection seems to be the first step to solve this problem and raise awareness about enhanced natural radioactivity for all stakeholders of concern. PMID:19809704

  6. Determination of naturally occurring radionuclides in soil samples of Ayranci, Turkey

    NASA Astrophysics Data System (ADS)

    Agar, Osman; Eke, Canel; Boztosun, Ismail; Emin Korkmaz, M.

    2015-04-01

    The specific activity, radiation hazard index and the annual effective dose of the naturally occurring radioactive elements (238U, 232Th and 40K) were determined in soil samples collected from 12 different locations in Ayranci region by using a NaI(Tl) gamma-ray spectrometer. The measured activity concentrations of the natural radionuclides in studied soil samples were compared with the corresponding results of different countries and the internationally reported values. From the analysis, it is found that these materials may be safely used as construction materials and do not pose significant radiation hazards.

  7. Structural consequences of chromophore formation and exploration of conserved lid residues amongst naturally occurring fluorescent proteins

    NASA Astrophysics Data System (ADS)

    Zimmer, Matthew H.; Li, Binsen; Shahid, Ramza; Peshkepija, Paola; Zimmer, Marc

    2014-01-01

    Computational methods were used to generate the lowest energy conformations of the immature precyclized forms of the 28 naturally occurring GFP-like proteins deposited in the pdb. In all 28 GFP-like proteins, the beta-barrel contracts upon chromophore formation and becomes more rigid. Our prior analysis of over 260 distinct naturally occurring GFP-like proteins revealed that most of the conserved residues are located in the top and bottom of the barrel in the turns between the β-sheets (Ong et al. 2011) [1]. Structural analyses, molecular dynamics simulations and the Anisotropic Network Model were used to explore the role of these conserved lid residues as possible folding nuclei. Our results are internally consistent and show that the conserved residues in the top and bottom lids undergo relatively less translational movement than other lid residues, and a number of these residues may play an important role as hinges or folding nuclei in the fluorescent proteins.

  8. Pyrethroid insecticides: A naturally occurring toxin. (Latest citations from Pollution Abstracts). Published Search

    SciTech Connect

    Not Available

    1993-05-01

    The bibliography contains citations concerning the effects of pyrethrum and pyrethroid insecticides. Topics examine toxicity to fish, worms, flies, mosquitoes, and moths. Chemical residue on crops, the transportation of pyrethrum from soils to crops, and pyrethrum accumulation in ponds and lakes are among the topics discussed. Naturally occurring and synthetic pyrethroid insecticides are included. (Contains a minimum of 173 citations and includes a subject term index and title list.)

  9. Bovine papillomavirus E7 oncoprotein binds to p600 in naturally occurring equine sarcoids.

    PubMed

    Corteggio, Annunziata; Di Geronimo, Ornella; Roperto, Sante; Roperto, Franco; Borzacchiello, Giuseppe

    2011-02-01

    Studies regarding the functions of the bovine papillomavirus (BPV) E7 oncoprotein in vivo are lacking and no E7-mediated mechanism underlying mesenchymal carcinogenesis is known. Here, we show that the interaction between the 600 kDa retinoblastoma protein-associated factor (p600) and BPV E7, described in vitro in cultured cells, takes place in vivo in naturally occurring equine sarcoids. In these cancers we detect the expression of E7 and p600, and demonstrate that E7 and p600 co-localize and physically interact. Furthermore, intracellular signals involved in p600 functional activity are found not to be overexpressed, suggesting a different functional activity of p600 in naturally occurring carcinogenesis. Our results demonstrate, for the first time, that E7-p600 interaction occurs during the natural history of BPV-induced equine tumours, suggesting an important role for E7 in carcinogenesis. Finally, the system provides a suitable animal model of papillomavirus-associated cancer to test therapeutic vaccination against E7. PMID:20965990

  10. California Dept. of Toxic Substances Control (DTSC) Update of the Schools Naturally Occurring Asbestos Guidance

    NASA Astrophysics Data System (ADS)

    Malinowski, M.

    2012-12-01

    Prior to acquisition and/or construction of prospective school sites, the California Education Code mandates that school districts complete environmental assessments and cleanups for prospective new or expanding school sites in order to qualify for state funding. If prospective school sites are determined to have environmental contamination from hazardous materials, including naturally occurring hazardous materials such as naturally occurring asbestos (NOA), where there may be unacceptable potential health risks, the school sites must be properly mitigated prior to occupancy for protection of human health and the environment. NOA is of special concern for schools, because children who are exposed to asbestos may be at increased risk of developing asbestos-related diseases over time. In order to protect human health, the Department of Toxic Substances Control's (DTSC) goals at school sites are to: 1) identify the presence of NOA in school site soils using exposure-reducing soil thresholds; 2) manage potential NOA exposures using mitigation measures to reduce generation of airborne asbestos fibers from soils on school sites; and 3) ensure long-term monitoring and protection of mitigation measures via Operations & Maintenance activities. DTSC is currently in the process of revising its Interim Guidance Naturally Occurring Asbestos (NOA) at School Sites - September 2004. The revisions include: 1) updating the guidance to consider incremental sampling for use at NOA sites in consultation with DTSC's project manager and technical staff, and 2) documenting a tiered approach to addressing high and low activity areas on a school.

  11. Segregation of Naturally Occurring Mitochondrial DNA Variants in a Mini-Pig Model.

    PubMed

    Cagnone, Gael; Tsai, Te-Sha; Srirattana, Kanokwan; Rossello, Fernando; Powell, David R; Rohrer, Gary; Cree, Lynsey; Trounce, Ian A; St John, Justin C

    2016-03-01

    The maternally inherited mitochondrial genome (mtDNA) is present in multimeric form within cells and harbors sequence variants (heteroplasmy). While a single mtDNA variant at high load can cause disease, naturally occurring variants likely persist at low levels across generations of healthy populations. To determine how naturally occurring variants are segregated and transmitted, we generated a mini-pig model, which originates from the same maternal ancestor. Following next-generation sequencing, we identified a series of low-level mtDNA variants in blood samples from the female founder and her daughters. Four variants, ranging from 3% to 20%, were selected for validation by high-resolution melting analysis in 12 tissues from 31 animals across three generations. All four variants were maintained in the offspring, but variant load fluctuated significantly across the generations in several tissues, with sex-specific differences in heart and liver. Moreover, variant load was persistently reduced in high-respiratory organs (heart, brain, diaphragm, and muscle), which correlated significantly with higher mtDNA copy number. However, oocytes showed increased heterogeneity in variant load, which correlated with increased mtDNA copy number during in vitro maturation. Altogether, these outcomes show that naturally occurring mtDNA variants segregate and are maintained in a tissue-specific manner across generations. This segregation likely involves the maintenance of selective mtDNA variants during organogenesis, which can be differentially regulated in oocytes and preimplantation embryos during maturation. PMID:26819245

  12. Elemental and Microscopic Analysis of Naturally Occurring C-O-Si Hetero-Fullerene-Like Structures.

    PubMed

    Hullavarad, Nilima V; Hullavarad, Shiva S; Fochesatto, Javier

    2015-03-01

    Carbon exhibits an ability to form a wide range of structures in nature. Under favorable conditions, carbon condenses to form hollow, spheroid fullerenes in an inert atmosphere. Using high resolution FESEM, we have concealed the existence of giant hetero-fullerene like structures in the natural form. Clear, distinct features of connected hexagons and pentagons were observed. Energy dispersive X-ray analysis depth-profile of natural fullerene structures indicates that Russian-doll-like configurations composed of C, 0, and Si rings exist in nature. The analysis is based on an outstanding molecular feature found in the size fraction of aerosols having diameters 150 nm to 1.0 m. The fullerene like structures, which are ~ 150 nm in diameter, are observed in large numbers. To the best of our knowledge, this is the first direct detailed observation of natural fullerene-like structures. This article reports inadvertent observation of naturally occurring hetero-fullerene-like structures in the Arctic. PMID:26413671

  13. Factors Affecting Comparative Resistance of Naturally Occurring and Subcultured Pseudomonas aeruginosa to Disinfectants

    PubMed Central

    Carson, L. A.; Favero, M. S.; Bond, W. W.; Petersen, N. J.

    1972-01-01

    A strain of Pseudomonas aeruginosa was isolated in pure culture from the reservoir of a hospital mist therapy unit by an extinction-dilution technique; its natural distilled water environment was used as a growth and maintenance medium. After a single subculture on Trypticase soy agar, the strain showed a marked decrease in resistance to inactivation by acetic acid, glutaraldehyde, chlorine dioxide, and a quaternary ammonium compound when compared with naturally occurring cells grown in mist therapy unit water. The following factors were observed to affect the relative resistances of naturally occurring and subcultured cells of the P. aeruginosa strain: (i) temperature at which the cultures were incubated prior to exposure to disinfectants, (ii) growth phase of the cultures at the time of exposure to disinfectants, (iii) nature of the suspending menstruum for disinfectants, and (iv) exposure to fluorescent light during incubation of inocula prior to testing. The applied significance of these findings may alter the present concepts of disinfectant testing as well as routine control procedures in the hospital environment. PMID:4624209

  14. Synthesis and Characterization of Arsenolipids: Naturally Occurring Arsenic Compounds in Fish and Algae

    PubMed Central

    2014-01-01

    Arsenic-containing lipids (arsenolipids) are natural products present in fish and algae. Because these compounds occur in foods, there is considerable interest in their human toxicology. We report the synthesis and characterization of seven arsenic-containing lipids, including six natural products. The compounds comprise dimethylarsinyl groups attached to saturated long-chain hydrocarbons (three compounds), saturated long-chain fatty acids (two compounds), and monounsaturated long chain fatty acids (two compounds). The arsenic group was introduced through sodium dimethylarsenide or bis(dimethylarsenic) oxide. The latter route provided higher and more reproducible yields, and consequently, this pathway was followed to synthesize six of the seven compounds. Mass spectral properties are described to assist in the identification of these compounds in natural samples. The pure synthesized arsenolipids will be used for in vitro experiments with human cells to test their uptake, biotransformation, and possible toxic effects. PMID:24683287

  15. Naturally occurring amino acid derivatives with herbicidal, fungicidal or insecticidal activity.

    PubMed

    Lamberth, Clemens

    2016-04-01

    Several naturally occurring amino acid derivatives display significant activities against weeds, fungi and insects: some of them have been even commercialized and are applied as crop protection agents. The 53 most important amino acid natural products with such efficacy are presented in this review together with their natural source, mode of action and biological activity. The diversity of the manifold bacterial, fungal and plantal sources of these compounds is impressive as well as their completely different structural scaffolds, ranging from cyclopeptides via unique non-proteinogenic amino acids to peptidyl nucleosides, the broad range of target enzymes from several different biochemical pathways, which they inhibit and also the plethora of different weeds, fungi and insects they are able to control. PMID:26801938

  16. Interactions with glutathione S-transferases of porphyrins used in photodynamic therapy and naturally occurring porphyrins.

    PubMed Central

    Smith, A; Nuiry, I; Awasthi, Y C

    1985-01-01

    Several naturally occurring porphyrins and porphyrins used in photodynamic therapy inhibit glutathione S-transferase isoenzymes either purified from rat liver or lung or in cytosol from normal and from cancerous (Morris 7288C hepatoma) liver. Although differences occur in the type and amount of transferases in normal and cancerous liver and in the liver of rats bearing an extrahepatic tumour, these enzymes are potential binding sites for porphyrins. Porphyrin structure is an important factor in determining the affinity of binding, as shown by the relative inhibitory effectiveness. Of the dicarboxylic porphyrins in the mixture used clinically, OO'-diacetylhaematoporphyrin and monohydroxyethylmonovinyldeuteroporphyrin are more effective inhibitors than haematoporphyrin and protoporphyrin IX. Of the naturally occurring porphyrins the order of effectiveness is protoporphyrin IX (dicarboxylic) greater than coproporphyrin (tetracarboxylic) greater than uroporphyrin (octacarboxylic) and type I greater than type III isomers of both uroporphyrin and coproporphyrin, and the synthetic tetra-meso-phenylporphinetetrasulphonate is a better inhibitor (apparent Ki = 250 nM) than coproporphyrin, which contains a comparable number of negative charges. In addition, iron-porphyrin chelates are more effective inhibitors of the transferases, with 25-fold decrease in Ki value, than the free porphyrins. These results indicate that one means whereby porphyrins accumulate in tissues is the occupation of intracellular binding sites, such as the transferases. Since porphyrins inhibit the activity of these important detoxifying enzymes, there will be metabolic consequences to the cell. PMID:4052030

  17. Alaska, Naturally Occurring Asbestos: Experiences, Policy and 2012 Limitation of Liability Legislation

    NASA Astrophysics Data System (ADS)

    Hargesheimer, J.; Perkins, R.

    2012-12-01

    Naturally Occurring Asbestos (NOA) occurs in mineral deposits in Alaska. There are many regions in Alaska that have minerals in surface rocks that may contain asbestos and asbestos has been discovered in many locations in Alaska. Gravel is constantly in demand for heavy construction projects, but some remote localities in Alaska do not have gravel sources that are NOA-free. Determining if NOA can be safely used in heavy construction materials and what can or should be done with NOA materials that are already in place are complex questions. Answers will depend on the amount and type of asbestos mineral, how it is handled in processing, and how it is maintained - all subject to regulation and control of operations. The State of Alaska recently enacted legislation (HB 258) providing, among other things, "… immunity for the state and for landowners, extractors, suppliers, transporters, and contractors for certain actions or claims arising in connection with the use of gravel or aggregate material containing naturally occurring asbestos in certain areas." Implementation of the law and interim regulations and guidance should enable use of NOA for heavy construction materials in Alaska, but as with any new law, it will take some time to understand its full scope and effect.

  18. Naturally occurring arsenic in the groundwater at the Kansas City Plant

    SciTech Connect

    Korte, N.E.

    1990-12-01

    This report describes an investigation concerning the presence of arsenic in concentrations exceeding 0.4 mg/L in the groundwater under the Department of Energy's Kansas City Plant (KCP). The study consisted of four distinct phases: a thorough review of the technical literature, a historical survey of arsenic use at the facility, a laboratory study of existing techniques for determining arsenic speciation, and a field program including water, soil, and sediment sampling. The historical survey and literature review demonstrated that plant activities had not released significant quantities of arsenic to the environment but that similar occurrences of arsenic in alluvial groundwater are widespread in the midwestern United States. Laboratory studies showed that a chromatographic separation technique was necessary to accurately determine arsenic speciation for the KCP groundwater samples. Field studies revealed that naturally occurring reducing conditions prevalent in the subsurface are responsible for dissolving arsenic previously sorbed by iron oxides. Indeed, the data demonstrated that the bulk arsenic concentration of site subsoils and sediments is {approximately}7 mg/kg, whereas the arsenic content of iron oxide subsamples is as high as 84 mg/kg. Literature showed that similar concentrations of arsenic in sediments occur naturally and are capable of producing the levels of arsenic found in groundwater monitoring wells at the KCP. The study concludes, therefore, that the arsenic present in the KCP groundwater is the result of natural phenomena. 44 refs., 8 figs., 14 tabs.

  19. Different Redox Response Elicited by Naturally Occurring Antioxidants in Human Endothelial Cells

    PubMed Central

    Giordo, Roberta; Cossu, Annalisa; Pasciu, Valeria; Hoa, Phu Thi; Posadino, Anna Maria; Pintus, Gianfranco

    2013-01-01

    Evidences that higher natural antioxidant (NA) intake provides protection against cardiovascular disease (CVD) are contradictory. Oxidative-induced endothelial cells (ECs) injury is the key step in the onset and progression of CVD and for this reason the cellular responses resulting from NA interaction with ECs are actively investigated. This study was designed to investigate the direct impact of different naturally occurring antioxidants on the intracellular ROS levels in cultured human ECs. NA-induced redox changes, in terms of modulation of the intracellular ROS levels, were assessed by using the ROS fluorescent probe 2',7'-dichlorodihydrofluorescein diacetate (H2DCF-DA). While caffeic and caftaric acid exerted an anti-oxidant effect, both coumaric acid and resveratrol were pro-oxidant. Anti- and pro-oxidant effects of the tested compounds were concentration dependent, showing the induction or the tendency to promote a pro-oxidant outcome with increasing concentrations. Interestingly, the anti- and pro-oxidant behavior of chlorogenic and ferulic acid was dependent on the basal intracellular redox state. Our data indicate that naturally occurring antioxidants are able to induce a rapid modification of the intracellular ROS levels in human ECs, which is dependent on both the applied concentration and the intracellular redox state. PMID:23730364

  20. Investigation of the resistance of some naturally occurring and synthetic inorganic ion exchangers against gamma radiation

    NASA Astrophysics Data System (ADS)

    Nilchi, A.; Khanchi, A.; Ghanadi Maragheh, M.; Bagheri, A.

    2003-02-01

    The effect of various doses of gamma radiation on the ion-exchange capacity, distribution coefficient values, elution behaviour, physical effect, pH titration and infrared spectra of some synthetic inorganic ion exchangers, namely the cerium substituted phosphates; and naturally occurring inorganic ion exchangers, zeolites from different parts of Iran, have been studied systematically. No significant change has been observed in the ion-exchange capacity (with the exception of CeP(Na), CeP(Di·Na) and zeolite 5 (deposits of arababad talas)), elution behaviour, physical effect, chemical stability and the infrared spectra of the synthetic ion exchangers irradiated upto a total dose of 200 kGy, while a change has been observed in the pH-titration and distribution behaviour. The increase in pH is sharper for irradiated samples with divalent cations than for the normal samples. Furthermore, the Kd values, and hence the selectivity towards certain cations increase with the total dose absorbed, reaching its optimum selectivity with the dose of 50-100 kGy. The natural zeolites chosen for these studies, show, similar pattern to those of synthetic ion exchangers, and in some cases an extremely high selectivity toward certain cations, like Be II. These make, zeolites, which are naturally occurring ion exchangers more viable economically, and extremely useful alternative in this industry.

  1. Articular Osteochondrosis: A Comparison of Naturally-Occurring Human and Animal Disease

    PubMed Central

    McCoy, Annette M; Toth, Ferenc; Dolvik, Nils I; Ekman, Stina; Ellermann, Jutta; Olstad, Kristin; Ytrehus, Bjornar; Carlson, Cathy S

    2013-01-01

    Background Osteochondrosis (OC) is a common developmental orthopedic disease affecting both humans and animals. Despite increasing recognition of this disease among children and adolescents, its pathogenesis is incompletely understood because clinical signs are often not apparent until lesions have progressed to end-stage, and examination of cadaveric early lesions is not feasible. In contrast, both naturally-occurring and surgically-induced animal models of disease have been extensively studied, most notably in horses and swine, species in which OC is recognized to have profound health and economic implications. The potential for a translational model of human OC has not been recognized in the existing human literature. Objective The purpose of this review is to highlight the similarities in signalment, predilection sites and clinical presentation of naturally-occurring OC in humans and animals and to propose a common pathogenesis for this condition across species. Study Design Review Methods The published human and veterinary literature for the various manifestations of OC was reviewed. Peer-reviewed original scientific articles and species-specific review articles accessible in PubMed (US National Library of Medicine) were eligible for inclusion. Results A broad range of similarities exists between OC affecting humans and animals, including predilection sites, clinical presentation, radiographic/MRI changes, and histological appearance of the end stage lesion, suggesting a shared pathogenesis across species. Conclusion This proposed shared pathogenesis for OC between species implies that naturally-occurring and surgically-induced models of OC in animals may be useful in determining risk factors and for testing new diagnostic and therapeutic interventions that can be used in humans. PMID:23954774

  2. Heteroaggregation of multiwall Carbon Nanotubes and Naturally Occurring Colloids in Aquatic Systems

    NASA Astrophysics Data System (ADS)

    Coogan, Patricia

    The heteroaggregation of engineered nanoparticles (ENPs) with naturally occurring colloids (NOCs) plays an important role in determining the ultimate fate and transport of nanomaterials in the environment. The objective of this research was to characterize the potential for heteroaggregation between functionalized multiwall carbon nanotubes (MWCNTs) with NOCs in the aquatic environment. Carboxylated MWCNTs (COOH-MWCNTs) and amine functionalized MWCNTs (NH2-MWCNTs) were studied. The natural clay kaolinite was chosen as a model NOC due to its widespread presence in the natural environment and unique charge heterogeneity. In this study, the aggregation between CNTs and kaolinite was analyzed for a range of CNT:NOC ratios and pH as well as in different source waters in a series of sedimentation and aggregation experiments. Sedimentation was monitored using ultraviolet-visible (UV-VIS) spectroscopy, while aggregation was characterized by dynamic light scattering. The heteroaggregation of the COOH-MWCNTs was found to be heavily dependent on pH and the CNT:NOC ratio. The sedimentation rate of the CNT-NOC mixture indicated by UV-VIS spectroscopy and average particle size measured by DLS both increased at low pH while the CNT solution remained stable over time when tested at the same solution chemistry. As the CNT:NOC ratio decreased, the CNT-NOC mixture demonstrated enhanced sedimentation behavior at pH 3. The enhanced sedimentation coupled with increasing particle size of the mixture indicated the presence of CNT-NOC heteroaggregates. At higher pH, no enhanced sedimentation occurred for the range of ratios tested. The NH2-MWCNTs were not dispersible at neutral pH were therefore only tested at pH 3. All solutions regardless of ratio indicated no significant evidence of enhanced sedimentation due to heteroaggregation for the NH 2-MWCNTs in this study. Filtered and unfiltered natural water samples from Lake Houston and the Trinity River were also analyzed and found to significantly enhance the sedimentation of the CNTs at neutral pH. The unfiltered samples exhibited enhanced sedimentation of the COOH-MWCNTs compared to the filtered samples. There was also evidence of enhanced removal of other particles present in the natural water sample due to the addition of CNTs. This indicates that the presence of CNTs could affect the transport of other contaminants in aquatic systems, altering the distribution of contaminants particularly at the sediment-water interface. These results suggest that NOCs enhance the sedimentation of CNTs in the natural environment and are highly dependent on pH and the ratio of carbon nanotube to natural colloid.

  3. Grafted self-assembled monolayers derived from naturally occurring phenolic lipids.

    PubMed

    Pillot, J-P; Birot, M; Tran, T T T; Dao, T M; Belin, C; Desbat, B; Lazare, S

    2005-04-12

    Self-assembled monolayers grafted onto silicon surfaces were obtained from the hydrosilylation products by trialcoxysilanes of naturally occurring phenolic lipid allyl ethers. The as-obtained materials were characterized by various physical and physicochemical methods. Thus, contact angles of water drops showed that they possess very high hydrophobicity. Their excellent regularity was corroborated by AFM microscopy. The frequencies of the stretching CH2 infrared modes indicate the presence of alkyl chains mainly in the trans/trans conformation. Additionally, optical ellipsometry and quartz microbalance measurements enabled us to estimate the thickness of the films. The results, as a whole, are in good agreement with the formation of densely packed monolayers. PMID:15807572

  4. Editing the genome to introduce a beneficial naturally occurring mutation associated with increased fetal globin.

    PubMed

    Wienert, Beeke; Funnell, Alister P W; Norton, Laura J; Pearson, Richard C M; Wilkinson-White, Lorna E; Lester, Krystal; Vadolas, Jim; Porteus, Matthew H; Matthews, Jacqueline M; Quinlan, Kate G R; Crossley, Merlin

    2015-01-01

    Genetic disorders resulting from defects in the adult globin genes are among the most common inherited diseases. Symptoms worsen from birth as fetal ?-globin expression is silenced. Genome editing could permit the introduction of beneficial single-nucleotide variants to ameliorate symptoms. Here, as proof of concept, we introduce the naturally occurring Hereditary Persistance of Fetal Haemoglobin (HPFH) -175T>C point mutation associated with elevated fetal ?-globin into erythroid cell lines. We show that this mutation increases fetal globin expression through de novo recruitment of the activator TAL1 to promote chromatin looping of distal enhancers to the modified ?-globin promoter. PMID:25971621

  5. Bay Area Air Quality Management District (BAAQMD) Naturally Occurring Asbestos Regulations and Enforcement Protocols

    NASA Astrophysics Data System (ADS)

    Wall, M.

    2012-12-01

    BAAQMD has been delegated local enforcement of the Naturally-Occurring Asbestos Airborne Toxic Control Measure for Construction, Grading, Quarrying, and Surface Mining Operations, Section 93105, Title 17, California Code of Regulation ("NOA ATCM") by the state Air Resource Board. BAAQMD will present an overview of how BAAQMD administers and enforces the NOA ATCM, as well as a discussion of various issues that have arisen at NOA projects BAAQMD has overseen, and steps that have been taken in the interest of protecting the public health.

  6. Bibliography of reports, papers, and presentations on naturally occurring radioactive material (NORM) in petroleum industry wastes

    SciTech Connect

    Smith, K.P.; Wilkey, M.L.; Hames, R.D.

    1997-07-01

    This bibliography was created to support projects conducted by Argonne National Laboratory (ANL) addressing issues related to naturally occurring radioactive material (NORM) in petroleum industry wastes. The bibliography provides citations for many of the available published reports, papers, articles, and presentations on petroleum industry NORM. In the past few years, the rapid expansion of NORM treatment and disposal technologies, the efforts to characterize NORM wastes and their associated potential risks, and the promulgation of state-level NORM regulatory programs have been well-documented in project reports and in papers presented at technical conferences and symposia. There are 221 citations.

  7. Towards the elusive structure of kotalanol, a naturally occurring glucosidase inhibitor.

    PubMed

    Mohan, Sankar; Pinto, B Mario

    2010-04-01

    This Highlight describes the detailed approach used to determine the absolute stereochemistry of the stereogenic centers in the acyclic side chain of kotalanol, a naturally occurring glucosidase inhibitor isolated from the plant Salacia reticulata. The plant extract itself is used in Ayurvedic medicine for the treatment of Type 2 diabetes. We highlight the syntheses of proposed candidates based on structure-activity relationships, the total synthesis of kotalanol, and crystallographic studies of kotalanol and its de-O-sulfonated derivative complexed with recombinant human maltase glucoamylase (MGA), a critical intestinal glucosidase involved in the breakdown of glucose oligomers into glucose. PMID:20336233

  8. Naturally occurring levels of elements in fishes as determined by PIXE and XRF methods

    NASA Astrophysics Data System (ADS)

    Tallandini, L.; Giacobini, F.; Turchetto, M.; Galassini, S.; Liu, Q. X.; Shao, H. R.; Moschini, G.; Moro, R.; Gialanella, G.; Ghermandi, G.; Cecchi, R.; Injuk, J.; Valkovi?, V.

    1989-04-01

    Naturally occurring levels of S, Cl, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Br, Sb, Sr and Pb were measured in the gills, liver and muscles of fishes ( Zosterisessor ophiocephalus Pall) in the northwestern region of the Adriatic Sea. The overall performance of PIXE and XRF methods was tested by the analysis of standard reference materials. The mean concentration values for elements were calculated from the distribution of experimentally determined concentration values. The obtained data are discussed in the framework of metal metabolism and toxicology.

  9. Naturally occurring phenanthrene degrading bacteria associated with seeds of various plant species.

    PubMed

    Fernet, Jennifer L; Lawrence, John R; Germida, James J

    2016-04-01

    Seeds of 11 of 19 plant species tested yielded naturally occurring phenanthrene degrading bacteria when placed on phenanthrene impression plates. Seed associated phenanthrene degrading bacteria were mostly detected on caragana, Canada thistle, creeping red fescue, western wheatgrass, and tall wheat grass. Based on 16S rRNA analysis the most common bacteria isolated from these seeds were strains belonging to the genera Enterobacteria, Erwinia, Burkholderia, Pantoea, Pseudomonas, and Sphingomonas. These plants may provide an excellent source of pre-adapted bacterial-plant associations highly suitable for use in remediation of contaminated soil environments. PMID:26515514

  10. Naturally occurring asbestos in eastern Australia: a review of geological occurrence, disturbance and mesothelioma risk

    NASA Astrophysics Data System (ADS)

    Hendrickx, Marc

    2009-04-01

    Potential asbestos-bearing rocks account for about 0.2% of the land area of eastern Australia. The main mode of occurrence is as narrow cross fibre and slip fibre veins of chrysotile asbestos in serpentinised ophiolite complexes along the boundaries of major tectonic domains. Smaller deposits of chrysotile and amphibole asbestos occur in metamorphosed mafic and ultramafic rocks associated with the Macquarie Volcanic Arc in New South Wales. Amphibole asbestos is also known from Proterozoic and Palaeozoic amphibolite and from Devonian basalt. Natural asbestos-bearing materials in eastern Australia have been disturbed by mining, road construction, agriculture and forestry, urban development and through natural weathering processes. Persons most at risk of potential exposure to asbestos from natural sources include: farmers who work or live in areas where asbestos-bearing materials may be routinely disturbed by agricultural activities; construction workers involved in large-scale earthwork projects in areas underlain by asbestos-bearing rocks; and quarry workers who unwittingly disturb asbestos-bearing materials. Government authorities and private enterprise need to take geological factors into account to reduce the likelihood of unplanned disturbance of natural asbestos-bearing materials.

  11. Cd Isotopic Composition Measured by Plasma Source Mass Spectrometry on Natural and Anthropogenic Materials. A Preliminary Outline of Cd Isotope Systematics

    NASA Astrophysics Data System (ADS)

    Innocent, C.

    2004-05-01

    Cadmium is a trace metal that is used as a geochemical tracer of natural processes, like biological productivity and paleoproductivity, and also of anthropogenic pollution, as Cd is known to be a toxic heavy metal that has become a major environmental and health concern. For these purposes, an outstanding issue is to determine whether Cd, like a number of metallic elements (e.g. Fe, Cu, Zn, Mo, Tl), may display variable isotopic compositions in natural and/or industrial compounds. It is known that Cd may display variable isotopic composition. Indeed, isotopic fractionation processes have been documented in some meteorites and in lunar soils. Consequently, due to its relatively low boiling point (767\\deg C) and also to the large mass range covered by its isotopes (10 mass units), Cd might fractionate isotopically, for example during the outpouring of acidic volcanic magmas and/or the emplacement of granitoids. On another hand, isotopic fractionation could also occur during human activities like refuse incineration or industrial manufacturing, for instance. Finally, biologically-induced isotopic fractionation should not be ruled out, as it is clearly evidenced for other metals, like Fe. A high precision method has been developed for determining the isotopic composition of Cd by plasma source mass spectrometry (Neptune). This method holds on the standard-bracketing technique, owing to the availability of Cd solutions of known isotopic composition provided by the University of M\\H{u}nster. This allows to correct precisely for mass fractionation that occurs in the plasma source mass spectrometer. It is also critical for the analysis to be possible to work with Cd solutions of very high purity. Chemical isolation of Cd involves 3 steps, and may be also suitable for Cd isotopic measurements using solid source mass spectrometry. Preliminary results suggest that Cd is likely to fractionate during smelting activities, as indicated by measurements on mining waste. The calibration of a 110Cd-116Cd double spike is underway for absolute, true isotopic ratios to be derived. The double spike technique allows the isotopic analysis of Cd using a plasma source, but also a solid source mass spectrometer, as Cd ionizes efficiently in such mass spectrometers owing to the standard silicagel technique.

  12. Identification of manganese as a toxicant in a groundwater treatment system: Addressing naturally occurring toxicants

    SciTech Connect

    Goodfellow, W. Jr.; Sohn, V.; Richey, M.; Yost, J.

    1995-12-31

    Effluent from a groundwater remediation system at a bulk oil storage and distribution terminal has been chronically toxic to Ceriodaphnia dubia. The remediation system was designed in response to a hydrocarbon plume in the area of the terminal. The remediation system consists of a series of groundwater recovery wells and groundwater intercept trench systems with groundwater treatment and phased-separated hydrocarbon recovery systems. The groundwater treatment and petroleum recovery systems consist of oil/water separators, product recovery tanks, air strippers, filters, and carbon adsorption units. The characteristics of this effluent are low total suspended solids, total dissolved solids, and hardness concentrations as well as meeting stringent NPDES permit requirements for lead, copper, zinc, mercury, total petroleum hydrocarbons, and BTEX. Additional priority pollutant evaluations revealed no compounds of concern. Performance of a Toxicity identification Evaluation (TIE) indicated that manganese was the principle toxicant in the effluent. Manganese is a naturally occurring constituent in this groundwater source and is not added to the treatment system. This paper will present the results of the TIE with a discussion of treatability/control options for manganese control at this facility. Recommendations for addressing naturally occurring toxicants that are not a result of the facility`s operations will also be presented.

  13. The role of mesoscale kinetic energy in natural occurring phytoplankton blooms and export in Drake Passage.

    NASA Astrophysics Data System (ADS)

    Davies, A. R.; Veron, F.; Oliver, M. J.

    2014-12-01

    The Southern Ocean is an iron limited, high nitrate, low chlorophyll region that draws considerable attention as a potential site for carbon drawdown through iron fertilization. However, there are no prolonged in-situ observations of the mechanisms driving naturally occurring blooms in this region. Here we present results from an APEX biofloat that continuously profiled the Drake Passage from ~ 2,000 m to the surface every two days. The biofloat measured the development and export of a naturally occurring phytoplankton bloom in the Drake Passage. Our analysis indicates that low levels of mesoscale kinetic energy coincided with the observed phytoplankton bloom. We postulate that low KE level are a precondition for bloom onset in the Drake Passage, which is confirmed by satellite observations. High levels of mesoscale kinetic energy immediately followed the phytoplankton bloom and appear to have facilitated organic carbon export to the deep ocean by changing the neutral density depths of aggregated cells. Furthermore, satellite observations in Drake Passage suggest that high levels of mesoscale kinetic energy limit bloom formation. We suggest that low mesoscale kinetic energy is a precondition for bloom formation in the Drake Passage before other potentially limiting factors become significant (e.g. grazing relation, macronutrients, micronutrients). If mesoscale kinetic energy were to impose a limitation on phytoplankton concentrations across the entire Southern Ocean, there may be regions unsuitable for geoengineered draw down of atmospheric carbon dioxide through large scale iron additions.

  14. A case of naturally occurring visual field loss in a chimpanzee with an arachnoid cyst.

    PubMed

    Kaneko, Takaaki; Sakai, Tomoko; Miyabe-Nishiwaki, Takako; Tomonaga, Masaki

    2013-11-01

    Deficits in the occipital cortex have varying consequences among mammalian species. Such variations are indicative of evolutionary transitions in the striate cortical contribution to visually guided behavior. However, little is known about the role of the striate cortex in visually guided behavior in chimpanzees due to ethical concerns about invasive experiments and methodological limitations such as the inability to monitor gaze movements. We had the opportunity to study the behavioral consequences of a deficit in the occipital cortex in a chimpanzee with a naturally occurring arachnoid cyst in her right occipital lobe. We assessed the chimpanzee's ability to detect a small light probe (0.5 visual degree, Michelson contrast > 0.9) presented at several locations in the visual field while monitoring gaze direction using an infra-red remote eye-tracker recently introduced to studies of great apes. The results showed the chimpanzee was unable to detect the probe in the lower left quadrant of the visual field, suggesting severe loss of contrast sensitivity in a part of hemivisual field that is retinotopically corresponded to the hemisphere of the cyst. A chimpanzee with a naturally occurring deficit in the right striate cortex and the availability of remote eye-tracking technology presented a unique opportunity to compare the role of the occipital lobe in visually guided behavior among various primate species. PMID:24036355

  15. Thermal resistance of naturally occurring airborne bacterial spores. [Viking spacecraft dry heat decontamination simulation

    NASA Technical Reports Server (NTRS)

    Puleo, J. R.; Bergstrom, S. L.; Peeler, J. T.; Oxborrow, G. S.

    1978-01-01

    Simulation of a heat process used in the terminal dry-heat decontamination of the Viking spacecraft is reported. Naturally occurring airborne bacterial spores were collected on Teflon ribbons in selected spacecraft assembly areas and subsequently subjected to dry heat. Thermal inactivation experiments were conducted at 105, 111.7, 120, 125, 130, and 135 C with a moisture level of 1.2 mg of water per liter. Heat survivors were recovered at temperatures of 135 C when a 30-h heating cycle was employed. Survivors were recovered from all cycles studied and randomly selected for identification. The naturally occurring spore population was reduced an average of 2.2 to 4.4 log cycles from 105 to 135 C. Heating cycles of 5 and 15 h at temperature were compared with the standard 30-h cycle at 111.7, 120, and 125 C. No significant differences in inactivation (alpha = 0.05) were observed between 111.7 and 120 C. The 30-h cycle differs from the 5- and 15-h cycles at 125 C. Thus, the heating cycle can be reduced if a small fraction (about 0.001 to 0.0001) of very resistant spores can be tolerated.

  16. Naturally Occurring Human Urinary Peptides for Use in Diagnosis of Chronic Kidney Disease*

    PubMed Central

    Good, David M.; Zrbig, Petra; Argils, ngel; Bauer, Hartwig W.; Behrens, Georg; Coon, Joshua J.; Dakna, Mohammed; Decramer, Stphane; Delles, Christian; Dominiczak, Anna F.; Ehrich, Jochen H. H.; Eitner, Frank; Fliser, Danilo; Frommberger, Moritz; Ganser, Arnold; Girolami, Mark A.; Golovko, Igor; Gwinner, Wilfried; Haubitz, Marion; Herget-Rosenthal, Stefan; Jankowski, Joachim; Jahn, Holger; Jerums, George; Julian, Bruce A.; Kellmann, Markus; Kliem, Volker; Kolch, Walter; Krolewski, Andrzej S.; Luppi, Mario; Massy, Ziad; Melter, Michael; Neusss, Christian; Novak, Jan; Peter, Karlheinz; Rossing, Kasper; Rupprecht, Harald; Schanstra, Joost P.; Schiffer, Eric; Stolzenburg, Jens-Uwe; Tarnow, Lise; Theodorescu, Dan; Thongboonkerd, Visith; Vanholder, Raymond; Weissinger, Eva M.; Mischak, Harald; Schmitt-Kopplin, Philippe

    2010-01-01

    Because of its availability, ease of collection, and correlation with physiology and pathology, urine is an attractive source for clinical proteomics/peptidomics. However, the lack of comparable data sets from large cohorts has greatly hindered the development of clinical proteomics. Here, we report the establishment of a reproducible, high resolution method for peptidome analysis of naturally occurring human urinary peptides and proteins, ranging from 800 to 17,000 Da, using samples from 3,600 individuals analyzed by capillary electrophoresis coupled to MS. All processed data were deposited in an Structured Query Language (SQL) database. This database currently contains 5,010 relevant unique urinary peptides that serve as a pool of potential classifiers for diagnosis and monitoring of various diseases. As an example, by using this source of information, we were able to define urinary peptide biomarkers for chronic kidney diseases, allowing diagnosis of these diseases with high accuracy. Application of the chronic kidney disease-specific biomarker set to an independent test cohort in the subsequent replication phase resulted in 85.5% sensitivity and 100% specificity. These results indicate the potential usefulness of capillary electrophoresis coupled to MS for clinical applications in the analysis of naturally occurring urinary peptides. PMID:20616184

  17. Photodynamic therapy of naturally occurring tumors in animals using a novel benzophenothiazine photosensitizer.

    PubMed

    Frimberger, A E; Moore, A S; Cincotta, L; Cotter, S M; Foley, J W

    1998-09-01

    5-Ethylamino-9-diethylaminobenzo[a]phenothiazinium chloride (EtNBS) is a novel photodynamic therapy (PDT) photosensitizer with efficacy against experimental murine tumors. In this preliminary study, dogs and cats with naturally occurring tumors were treated with EtNBS-PDT to determine safety and efficacy. Fifteen treatments were performed on 13 animals (9 treatments in 8 cats and 6 treatments in 5 dogs), generally using 400 J of 652 nm light. Two feline sublingual squamous cell carcinomas (SCCs) responded briefly (minor response). Six feline facial SCCs were treated, resulting in two partial responses and four long-term complete responses (CR). Two canine intraoral SCCs were treated; one responded minimally for 2 weeks (minor response), and one achieved long-term CR. One canine cutaneous mast cell tumor achieved CR, and one canine ocular mast cell tumor responded briefly. One canine ocular melanoma did not respond to treatment. Systemic reactions included nausea associated with photosensitizer injection in two cats and two dogs, elevated body temperatures during treatment in two dogs, elevated body temperature 2 days after PDT in one cat, and inappetance for 2 weeks in one cat. A peripheral neuropathy of undetermined cause occurred in one cat 2 weeks after PDT and resolved without treatment. Local reaction was well tolerated in 13 of 15 treatments. All animals were exposed to normal daylight after less than 5 days (mean, 3.5 days) without residual photosensitization. EtNBS-PDT is safe for dogs and cats and has activity against selected naturally occurring tumors, with an overall objective response rate (partial response + CR) of 61.5%. PMID:9748141

  18. Reactive Neurogenesis in Response to Naturally Occurring Apoptosis in an Adult Brain

    PubMed Central

    Larson, Tracy A.; Thatra, Nivretta M.; Lee, Brian H.

    2014-01-01

    Neuronal birth and death are tightly coordinated to establish and maintain properly functioning neural circuits. Disruption of the equilibrium between neuronal birth and death following brain injury or pharmacological insult often induces reactive, and in some cases regenerative, neurogenesis. Many neurodegenerative disorders are not injury-induced, however, so it is critical to determine if and how reactive neurogenesis occurs under noninjury-induced neurodegenerative conditions. Here, we used a model of naturally occurring neural degradation in a neural circuit that controls song behavior in Gambel's white-crowned sparrows (Zonotrichia leucophrys gambelii) and examined the temporal dynamics between neuronal birth and death. We found that during seasonal-like regression of the song, control nucleus HVC (proper name), caspase-mediated apoptosis increased within 2 d following transition from breeding to nonbreeding conditions and neural stem-cell proliferation in the nearby ventricular zone (VZ) increased shortly thereafter. We show that inhibiting caspase-mediated apoptosis in HVC decreased neural stem-cell proliferation in the VZ. In baseline conditions the extent of neural stem-cell proliferation correlated positively with the number of dying cells in HVC. We demonstrate that as apoptosis increased and the number of both recently born and pre-existing neurons in HVC decreased, the structure of song, a learned sensorimotor behavior, degraded. Our data illustrate that reactive neurogenesis is not limited to injury-induced neuronal death, but also can result from normally occurring degradation of a telencephalic neural circuit. PMID:25253853

  19. Preclinical characterization of naturally occurring polyketide cyclophilin inhibitors from the sanglifehrin family.

    PubMed

    Gregory, Matthew A; Bobardt, Michael; Obeid, Susan; Chatterji, Udayan; Coates, Nigel J; Foster, Teresa; Gallay, Philippe; Leyssen, Pieter; Moss, Steven J; Neyts, Johan; Nur-e-Alam, Mohammad; Paeshuyse, Jan; Piraee, Mahmood; Suthar, Dipen; Warneck, Tony; Zhang, Ming-Qiang; Wilkinson, Barrie

    2011-05-01

    Cyclophilin inhibitors currently in clinical trials for hepatitis C virus (HCV) are all analogues of cyclosporine (CsA). Sanglifehrins are a group of naturally occurring cyclophilin binding polyketides that are structurally distinct from the cyclosporines and are produced by a microorganism amenable to biosynthetic engineering for lead optimization and large-scale production by fermentation. Preclinical characterization of the potential utility of this class of compounds for the treatment of HCV revealed that the natural sanglifehrins A to D are all more potent than CsA at disrupting formation of the NS5A-CypA, -CypB, and -CypD complexes and at inhibition of CypA, CypB, and CypD isomerase activity. In particular, sanglifehrin B (SfB) was 30- to 50-fold more potent at inhibiting the isomerase activity of all Cyps tested than CsA and was also shown to be a more potent inhibitor of the 1b subgenomic replicon (50% effective concentrations [EC50s] of 0.070 ?M and 0.16 ?M in Huh 5-2 and Huh 9-13 cells, respectively). Physicochemical and mouse pharmacokinetic analyses revealed low oral bioavailability (F<4%) and low solubility (<25 ?M), although the half-lives (t1/2) of SfA and SfB in mouse blood after intravenous (i.v.) dosing were long (t1/2>5 h). These data demonstrate that naturally occurring sanglifehrins are suitable lead compounds for the development of novel analogues that are less immunosuppressive and that have improved metabolism and pharmacokinetic properties. PMID:21383094

  20. Naturally occurring conjugated octadecatrienoic acids are strong inhibitors of prostaglandin biosynthesis.

    PubMed

    Nugteren, D H; Christ-Hazelhof, E

    1987-03-01

    Fatty acids from natural sources (mostly seed oils) were isolated and assayed for their effect on the bioconversion of arachidonic acid into prostaglandin E2, using sheep vesicular gland microsomes. Homologues and isomers of the naturally occurring fatty acids, obtained by chemical modification and/or organic synthetic methods, were also tested. Two very active cyclooxygenase inhibitors were discovered, namely jacarandic acid (8Z, 10E, 12Z-octadecatrienoic acid), isolated from Jacaranda mimosifolia, the concentration which gives 50% inhibition ([I]50) being 2.4 microM and the synthetic 8Z, 10E, 12E-octadecatrienoic acid, having an [I]50 of 1.0 microM. Under the conditions of the assay (75 microM substrate), earlier described potent inhibitors showed the following [I]50's: indomethacin: 1.3 microM; 9,12-octadecadiynoic acid: 1.3 microM, 8Z, 12E, 14Z-eicosatrienoic acid: 2.7 microM; 5,8,11,14-eicosatetraynoic acid: 4.4 microM. At a concentration of about half that of the substrate, the following naturally occurring fatty acids revealed inhibition ([I]50): columbinic acid (29 microM), calendulic acid (31 microM), liagoric acid (31 microM), ximenynic acid (39 microM), crepenynic acid (40 microM) and timnodonic acid (43 microM). Other fatty acids, and some of the above acids, were converted themselves more or less rapidly, mostly into conjugated monohydroxy fatty acids. PMID:3107083

  1. Natural Ca Isotope Composition of Urine as a Rapid Measure of Bone Mineral Balance

    NASA Astrophysics Data System (ADS)

    Skulan, J.; Gordon, G. W.; Morgan, J.; Romaniello, S. J.; Smith, S. M.; Anbar, A. D.

    2011-12-01

    Naturally occurring stable Ca isotope variations in urine are emerging as a powerful tool to detect changes in bone mineral balance. Bone formation depletes soft tissue of light Ca isotopes while bone resorption releases isotopically light Ca into soft tissue. Previously published work found that variations in Ca isotope composition could be detected at 4 weeks of bed rest in a 90-day bed rest study (data collected at 4, 8 and 12 weeks). A new 30-day bed rest study involved 12 patients on a controlled diet, monitored for 7 days prior to bed rest and 7 days post bed rest. Samples of urine, blood and food were collected throughout the study. Four times daily blood samples and per void urine samples were collected to monitor diurnal or high frequency variations. An improved chemical purification protocol, followed by measurement using multiple collector inductively coupled plasma mass spectrometry (MC-ICP-MS) allowed accurate and precise determinations of mass-dependent Ca isotope variations in these biological samples to better than 0.2% (?44/42Ca) on <25 ?g of Ca. Results from this new study show that Ca isotope ratios shift in a direction consistent with net bone loss after just 7 days, long before detectible changes in bone density by X-ray measurements occur. Consistent with this interpretation, the Ca isotope variations track changes observed in N-teleopeptide, a bone resorption biomarker. Bone-specific alkaline phosphatase, a bone formation biomarker, is unchanged over this period. Ca isotopes can in principle be used to quantify net changes in bone mass. Using a mass-balance model, our results indicate an average loss of 0.62 0.16 % in bone mass over the course of this 30-day study. This is consistent with the rate of bone loss in longer-term studies as seen by X-ray measurements. This Ca isotope technique should accelerate the pace of discovery of new treatments for bone disease and provide novel insights into the dynamics of bone metabolism.

  2. Influence of easily degradable naturally occurring carbon substrates on biodegradation of monosubstituted phenols by aquatic bacteria

    SciTech Connect

    Shimp, R.J.; Pfaender, F.K.

    1985-02-01

    The influence of readily degradable, naturally occurring carbon substrates on the biodegradation of several monosubstituted phenols (m-cresol, m-aminophenol, p-chlorophenol) was examined. The natural substrate classes used were amino acids, carbohydrates, and fatty acids. Samples of the microbial community from Lake Michie, a mesotrophic reservoir, were adapted to different levels of representatives from each natural substrate class in chemostats. After an extended adaptation period, the ability of the microbial community to degrade the monosubstituted phenols was determined by using a radiolabeled substrate uptake and mineralization method. Several microbiological characteristics of the communities were also measured. Adaptation to increasing concentrations of amino acids, carbohydrates, or fatty acids enhanced the ability of the microbial community to degrade all three phenols. The stimulation was largest for m-cresol and m-aminophenol. The mechanism responsible for the enhancement of monosubstituted phenol metabolism was not clearly identified, but the observation that adaptation to amino acids also increased the biodegradation of glucose and, to a lesser extend, naphthalene suggests a general stimulation of microbial metabolism.

  3. From phenotypic to molecular polymorphisms involved in naturally occurring variation of plant development.

    PubMed

    Alonso-Blanco, Carlos; Mendez-Vigo, Beln; Koornneef, Maarten

    2005-01-01

    An enormous amount of naturally occurring genetic variation affecting development is found within wild and domesticated plant species. This diversity is presumably involved in plant adaptation to different natural environments or in human preferences. In addition, such intraspecific variation provides the basis for the evolution of plant development at larger evolutionary scales. Natural phenotypic differences are now amenable to genetic dissection up to the identification of causal DNA polymorphisms. Here we describe 30 genes and their functional nucleotide polymorphisms currently found as underlying allelic variation accounting for plant intraspecific developmental diversity. These studies provide molecular and cellular mechanisms that determine natural variation for quantitative and qualitative traits such as: fruit and seed morphology, colour and composition; flowering time; seedling emergence; plant architecture and inflorescence or flower morphology. Besides, analyses of flowering time variation within several distant species allow molecular comparisons between species, which are detecting homologous genes with partly different functions and unrelated genes with analogous functions. Thus, considerable gene function differences are being revealed also among species. Inspection of a catalogue of intraspecific nucleotide functional polymorphisms shows that transcriptional regulators are the main class of genes involved. Furthermore, barely more than half of the polymorphisms described are located in coding regions and affect protein structure, while the rest are regulatory changes altering gene expression. These limited analyses of intraspecific developmental variation support Doebley and Lukens's proposition (1998) that modifications in cis -regulatory regions of transcriptional regulators represent a predominant mode for the evolution of novel forms, but await more detailed studies in wild plant species. PMID:16096977

  4. Beneficial Effects of Autologous Bone Marrow-Derived Mesenchymal Stem Cells in Naturally Occurring Tendinopathy

    PubMed Central

    Smith, Roger Kenneth Whealands; Werling, Natalie Jayne; Dakin, Stephanie Georgina; Alam, Rafiqul; Goodship, Allen E.; Dudhia, Jayesh

    2013-01-01

    Tendon injuries are a common age-related degenerative condition where current treatment strategies fail to restore functionality and normal quality of life. This disease also occurs naturally in horses, with many similarities to human tendinopathy making it an ideal large animal model for human disease. Regenerative approaches are increasingly used to improve outcome involving mesenchymal stem cells (MSCs), supported by clinical data where injection of autologous bone marrow derived MSCs (BM-MSCs) suspended in marrow supernatant into injured tendons has halved the re-injury rate in racehorses. We hypothesized that stem cell therapy induces a matrix more closely resembling normal tendon than the fibrous scar tissue formed by natural repair. Twelve horses with career-ending naturally-occurring superficial digital flexor tendon injury were allocated randomly to treatment and control groups. 1X107 autologous BM-MSCs suspended in 2 ml of marrow supernatant were implanted into the damaged tendon of the treated group. The control group received the same volume of saline. Following a 6 month exercise programme horses were euthanized and tendons assessed for structural stiffness by non-destructive mechanical testing and for morphological and molecular composition. BM-MSC treated tendons exhibited statistically significant improvements in key parameters compared to saline-injected control tendons towards that of normal tendons and those in the contralateral limbs. Specifically, treated tendons had lower structural stiffness (p<0.05) although no significant difference in calculated modulus of elasticity, lower (improved) histological scoring of organisation (p<0.003) and crimp pattern (p<0.05), lower cellularity (p<0.007), DNA content (p<0.05), vascularity (p<0.03), water content (p<0.05), GAG content (p<0.05), and MMP-13 activity (p<0.02). Treatment with autologous MSCs in marrow supernatant therefore provides significant benefits compared to untreated tendon repair in enhancing normalisation of biomechanical, morphological, and compositional parameters. These data in natural disease, with no adverse findings, support the use of this treatment for human tendon injuries. PMID:24086616

  5. Beneficial effects of autologous bone marrow-derived mesenchymal stem cells in naturally occurring tendinopathy.

    PubMed

    Smith, Roger Kenneth Whealands; Werling, Natalie Jayne; Dakin, Stephanie Georgina; Alam, Rafiqul; Goodship, Allen E; Dudhia, Jayesh

    2013-01-01

    Tendon injuries are a common age-related degenerative condition where current treatment strategies fail to restore functionality and normal quality of life. This disease also occurs naturally in horses, with many similarities to human tendinopathy making it an ideal large animal model for human disease. Regenerative approaches are increasingly used to improve outcome involving mesenchymal stem cells (MSCs), supported by clinical data where injection of autologous bone marrow derived MSCs (BM-MSCs) suspended in marrow supernatant into injured tendons has halved the re-injury rate in racehorses. We hypothesized that stem cell therapy induces a matrix more closely resembling normal tendon than the fibrous scar tissue formed by natural repair. Twelve horses with career-ending naturally-occurring superficial digital flexor tendon injury were allocated randomly to treatment and control groups. 1X10(7) autologous BM-MSCs suspended in 2 ml of marrow supernatant were implanted into the damaged tendon of the treated group. The control group received the same volume of saline. Following a 6 month exercise programme horses were euthanized and tendons assessed for structural stiffness by non-destructive mechanical testing and for morphological and molecular composition. BM-MSC treated tendons exhibited statistically significant improvements in key parameters compared to saline-injected control tendons towards that of normal tendons and those in the contralateral limbs. Specifically, treated tendons had lower structural stiffness (p<0.05) although no significant difference in calculated modulus of elasticity, lower (improved) histological scoring of organisation (p<0.003) and crimp pattern (p<0.05), lower cellularity (p<0.007), DNA content (p<0.05), vascularity (p<0.03), water content (p<0.05), GAG content (p<0.05), and MMP-13 activity (p<0.02). Treatment with autologous MSCs in marrow supernatant therefore provides significant benefits compared to untreated tendon repair in enhancing normalisation of biomechanical, morphological, and compositional parameters. These data in natural disease, with no adverse findings, support the use of this treatment for human tendon injuries. PMID:24086616

  6. In vitro surface characterization of a biological patch fixed with a naturally occurring crosslinking agent.

    PubMed

    Sung, H W; Chen, C N; Huang, R N; Hsu, J C; Chang, W H

    2000-07-01

    The study was designed to characterize the surface properties (including water contact angle, surface tension, protein adsorption, platelet adhesion, and cellular compatibility) of a biological patch fixed with genipin, a naturally occurring crosslinking agent. Fresh and glutaraldehyde-fixed counterparts were used as controls. It was found that both glutaraldehyde and genipin are effective crosslinking agents for biological tissue fixation. Fixation of biological tissue with glutaraldehyde or genipin significantly increased its hydrophilicity and surface tension and reduced its mol ratio of adsorbed fibrinogen to adsorbed albumin as well as the amount of adhered platelet. There were no significant differences in hydrophilicity, surface tension, the mole ratio of adsorbed fibrinogen to adsorbed albumin, and the amount of platelet adhesion between the glutaraldehyde- and genipin-fixed tissues. However, the cellular compatibilities of fresh and the genipin-fixed tissues were significantly superior to the glutaraldehyde-fixed tissue. PMID:10850929

  7. The effect of various naturally occurring metal-binding compounds on the electrochemical behavior of aluminum

    SciTech Connect

    Hansen, D.C.; McCafferty, E.

    1996-01-01

    Naturally occurring biological molecules are of considerable interest as possible corrosion inhibitors because of increased attention on the development of environmentally compatible, nonpolluting corrosion inhibitors. A hydroxamate yeast siderophore (rhodotorulic acid), a catecholate bacterial siderophore (parabactin), an adhesive protein from the blue mussel Mytilus edulis, and two metal-binding compounds isolated from the tomato and sunflower roots, namely, chlorogenic and caffeic acid, respectively, were adsorbed from solution onto pure aluminum (99.9995%) and their effect on the critical pitting potential and polarization resistance in deaerated 0.1 M NaCl was measured. These measurements were made using anodic polarization and ac impedance spectroscopy. The catechol-containing siderophore has an inhibitive effect on the critical pitting potential of aluminum in 0.1 M NaCl and increases the polarization resistance of the metal over time. The adhesive protein from the blue mussel is also effective in inhibiting the pitting of aluminum.

  8. Determination of naturally occurring radionuclides in liquid wastes from mining and milling

    SciTech Connect

    Bayat, I.; Etehadian, M.; Ansar, M.

    1995-12-31

    An analytical method has been developed for the separation and determination of naturally occurring radionuclides (primordial and its decay products in ore samples and liquid wastes from mining and milling process). The radionuclides include U-238, Th-232, Ra-226, Pb-210 and Po-210. The methodology involves three steps: (1) Complete sample dissolution by wet oxidation; (2) Sequential separation of radionuclides by ion exchange and co-precipitation; and (3) Radiometric determination by alpha, beta and gamma counting spectroscopy. The detection limit for a radiochemical yield of approximately 72%, was 0.28 mBq per sample for Th-232, U-238 and Po-210. To test it`s applicability, the method was used with standard ore samples, soil and sediment. The analytical procedure was applied to a large number of liquid waste samples and the results of these analysis are presented.

  9. Systems and methods for facilitating hydrogen storage using naturally occurring nanostructure assemblies

    DOEpatents

    Fliermans; , Carl B.

    2012-08-07

    Some or all of the needs above can be addressed by embodiments of the invention. According to embodiments of the invention, systems and methods for facilitating hydrogen storage using naturally occurring nanostructure assemblies can be implemented. In one embodiment, a method for storing hydrogen can be provided. The method can include providing diatoms comprising diatomaceous earth or diatoms from a predefined culture. In addition, the method can include heating the diatoms in a sealed environment in the presence of at least one of titanium, a transition metal, or a noble metal to provide a porous hydrogen storage medium. Furthermore, the method can include exposing the porous hydrogen storage medium to hydrogen. In addition, the method can include storing at least a portion of the hydrogen in the porous hydrogen storage medium.

  10. El Dorado Air Quality Management District's Approach to Dealing With Naturally Occurring Asbestos (NOA) Hazards

    NASA Astrophysics Data System (ADS)

    Thomas, C.

    2012-12-01

    In 2005, Naturally Occurring Asbestos (NOA) in El Dorado County made headlines with the discovery significant amounts of tremolite/actinolite asbestos in areas where residents had built, or were in the process of building, homes and residences. The El Dorado Air Quality Management District has been involved in all aspects of dealing with NOA from the very beginning of its discovery, from overseeing the rehabilitation of school sites to expanding and rewriting fugitive dust rules at construction sites. A discussion of best management practices which have been developed will be given, as well as how the El Dorado Air Quality Management District has worked to educate members of the public, as well as workers in the field, about NOA to aid in maintaining the health and safety of the public.

  11. Effect of genipin, a naturally occurring crosslinker on the properties of kappa-carrageenan.

    PubMed

    Meena, Ramavatar; Prasad, Kamalesh; Siddhanta, A K

    2007-06-01

    Genipin-fixed kappa-carrageenan was prepared in ambient conditions in aqueous solution using genipin, a naturally occurring crosslinker with kappa-carrageenan (kappaC). The crosslinked kappaC showed the greatest swelling capacity in acidic medium having pH 1.2 when compared to those in neutral and alkaline media. Enhanced stability of the crosslinked product with respect to the non-modified kappaC was confirmed by degradation studies in Ringer's solution, rheological and thermogravimetric measurements. Genipin fixation of kappaC was confirmed by measuring the bulk density, true density, pore volume, porosity, intrinsic viscosity, UV absorbance and optical rotation of the crosslinked kappaC, and as well as by optical microscopy, SEM, and MS/MS studies. The crosslinked product may be useful as super absorbent and sustained release formulation in biomedical applications. PMID:17339049

  12. Effects of some naturally-occurring purine ribosides on purinergic receptors in cardiac and smooth muscle.

    PubMed

    Fuhrman, F A; Fuhrman, G J

    1982-01-01

    1. Certain marine sponges and dorid nudibranchs contain adenosine, 2-methoxyadenosine, 2'-deoxyadenosine, isoguanosine and 1-methylisoguanosine as free ribosides. 2. These ribosides have negative inotropic and chronotropic activity on the isolated guinea-pig atria. The decreasing order of activity is isoguanosine greater than 1-methylisoguanosine greater than adenosine greater than 2-methyoxyadenosine greater than 2-deoxyadenosine. 3. Adenosine and 1-methylisoguanosine inhibit the spontaneous contractions of the rabbit ileum and this effect is antagonized by theophylline. 4. All these naturally-occurring purine ribosides appear to act on the same purinergic receptors in the atria, since log concentration-response curves are parallel. 5. Theophylline is a competitive antagonist of adenosine, isoguanosine and 1-methylisoguanosine on the guinea-pig atria. PMID:6128140

  13. Naturally-occurring excitatory amino acids as neurotoxins and leads in drug design.

    PubMed

    Krogsgaard-Larsen, P; Hansen, J J

    1992-12-01

    The central excitatory neurotransmitter (S)-glutamic acid (Glu) activates at least three types of receptors the NMDA, AMPA, and kainic acid (KAIN) receptors. These receptors mediate the neurotoxicity of a number of naturally-occurring Glu analogues. Thus, domoic acid, a KAIN receptor agonist, has probably been the cause of severe neurologic illness in people who consumed domoic acid poisoned food. beta-N-oxalylaminoalanine (beta-ODAP), an AMPA receptor agonist, has been associated with lathyrism, a spastic paraparesis caused by dietary intake of Lathyrus sativus. The neurotoxic Amanita muscaria constituent ibotenic acid, a nonselective NMDA receptor agonist, has been used as a lead structure for the development of the specific NMDA receptor agonist AMAA, AMPA, and a number of therapeutically interesting AMPA and KAIN receptor agonists. PMID:1335179

  14. Poly(anhydride-esters) comprised exclusively of naturally occurring antimicrobials and EDTA: antioxidant and antibacterial activities.

    PubMed

    Carbone-Howell, Ashley L; Stebbins, Nicholas D; Uhrich, Kathryn E

    2014-05-12

    Carvacrol, thymol, and eugenol are naturally occurring phenolic compounds known to possess antimicrobial activity against a range of bacteria, as well as antioxidant activity. Biodegradable poly(anhydride-esters) composed of an ethylenediaminetetraacetic acid (EDTA) backbone and antimicrobial pendant groups (i.e., carvacrol, thymol, or eugenol) were synthesized via solution polymerization. The resulting polymers were characterized to confirm their chemical composition and understand their thermal properties and molecular weight. In vitro release studies demonstrated that polymer hydrolytic degradation was complete after 16 days, resulting in the release of free antimicrobials and EDTA. Antioxidant and antibacterial assays determined that polymer release media exhibited bioactivity similar to that of free compound, demonstrating that polymer incorporation and subsequent release had no effect on activity. These polymers completely degrade into components that are biologically relevant and have the capability to promote preservation of consumer products in the food and personal care industries via antimicrobial and antioxidant pathways. PMID:24702678

  15. Ultra-trace Measurements of 210Pb in natural occurring radioactive materials by ICP-MS

    NASA Astrophysics Data System (ADS)

    Amr, M. A.; Al-Saad, K. A.; Helal, A. I.

    2010-04-01

    Collision cell inductively coupled plasma mass spectrometry (CC-ICP-MS) was investigated as a possible alternative to nuclear analytical techniques for the determination of 210Pb. The formation of isobaric and polyatomic interferences was studied. Following the acid digestion, extraction chromatography was tested to assess their usefulness in reducing its interferences. A 210Pb pre-concentration of >300-fold and recoveries of 63-73% were obtained using a combined extraction chromatography and pre-concentration by evaporation protocol. Improvement in sensitivity of 210Pb was found by optimization of the collision cell parameters using krypton as a collision gas. The detection limit was improved by a factor of 300 for 210Pb. A detection limit of 0.214 ppt (0.698 Bq/mL) was obtained. The method was applied to determine 210Pb in samples of naturally occurring radioactive materials (NORM).

  16. Gene conversion is involved in the transfer of genetic information between naturally occurring inversions of Drosophila.

    PubMed Central

    Rozas, J; Aguadé, M

    1994-01-01

    The DNA sequences of the ribosomal protein 49 (rp49) region were determined for 34 isochromosomal strains of Drosophila subobscura representing two chromosomal arrangements, the OST and the O3 + 4 gene arrangements, which differ by two overlapping inversions. The data reveal that gene conversion is a mechanism responsible for the transfer of genetic information between naturally occurring inversions of Drosophila. The estimated rate of gene transfer by gene conversion at this region, which is close to an inversion breakpoint, is lower than previous estimates obtained experimentally at the rosy (ry) gene in Drosophila melanogaster. Our data indicate that gene arrangements OST and O3 + 4 are monophyletic and rather old (0.58 and 0.73 million years old, respectively). Images PMID:7972094

  17. Effect of mangiferin, a naturally occurring glucoxylxanthone, on fear memory in rats.

    PubMed

    Andreu, Gilberto L Pardo; Maurmann, Natasha; Reolon, Gustavo Kellermann; de Farias, Caroline Brunetto; Delgado, René; Roesler, Rafael

    2011-01-01

    Mangiferin (1,3,6,7-tetrahydroxy-2-[3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl] -xanthen-9-one, CAS 4773-96-0), a naturally occurring glucosylxanthone, is widely distributed in higher plants and a constituent of folk medicine. In the present study the effect of systemic administration of mangiferin on behavioural outcomes of neurological function in normal rats was investigated. A single intraperitoneal injection of mangiferin (10, 50 and 100 mg/kg body weight) immediately post-training produced an impairment of long-term memory for aversive training and a reduced freezing in a dose independent manner, when given immediately post-training. The administration of mangiferin 6 h post-training did not affect fear memory. The results indicate that mangiferin might induce deficits of emotionally motivated memory. PMID:21899205

  18. Localized surface plasmon resonance effects by naturally occurring Chinese yam particles

    NASA Astrophysics Data System (ADS)

    Li, Quanshui; Zhang, Zhili; Haque, Sara S.; Zhang, Mingjun; Xia, Lijin

    2010-12-01

    In this paper, localized surface plasmon resonance (LSPR) effects by naturally occurring Chinese yam particles are observed and quantified. Chinese yam particles were found by atomic force microscope and high-speed optical dark-field microscope. The particles with diameters greater than 200 nm are found to contribute most of ultraviolet and visible absorption. LSPR effects of silver nanoparticles by the Chinese yam particles lead to the redshifts in the extinction peaks of the silver nanoparticles. The wavelength shifts are quantitatively predicted based on discrete dipole approximation of the LSPR effects, which are sensitive to the local dielectric constant changed by the Chinese yam particles. The finding may open a new avenue to detect the biological submicron particles or virus in solution.

  19. The corrosion inhibition of iron and aluminum by various naturally occurring biological molecules

    SciTech Connect

    McCafferty, E.; Hansen, D.C.

    1995-12-31

    Biological polymers that exhibit a strong affinity for metal surfaces are increasingly becoming the focus of research toward the development of environmentally friendly corrosion inhibitors. This paper deals with the use of various naturally occurring organic molecules as corrosion inhibitors for iron or aluminum. Among the organic molecules considered are catecholate and hydroxamate siderophores isolated from bacteria, the adhesive protein from the blue mussel Mytilus edulis L, and caffeic acid and chlorogenic acid. FTIR analysis, anodic polarization curves, and AC impedance measurements were used to determine the adsorption and effectiveness of the various organic molecules as corrosion inhibitors. Parabactin, a catecholate siderophore, was effective in inhibiting both the corrosion of iron in hydrochloric acid and the pitting of aluminum in 0.1 M sodium chloride. The adhesive protein from the blue mussel was also effective in inhibiting the pitting of aluminum.

  20. Naturally Occurring Triggers that Induce Apoptosis-Like Programmed Cell Death in Plasmodium berghei Ookinetes

    PubMed Central

    Ali, Medhat; Al-Olayan, Ebtesam M.; Lewis, Steven; Matthews, Holly; Hurd, Hilary

    2010-01-01

    Several protozoan parasites have been shown to undergo a form of programmed cell death that exhibits morphological features associated with metazoan apoptosis. These include the rodent malaria parasite, Plasmodium berghei. Malaria zygotes develop in the mosquito midgut lumen, forming motile ookinetes. Up to 50% of these exhibit phenotypic markers of apoptosis; as do those grown in culture. We hypothesised that naturally occurring signals induce many ookinetes to undergo apoptosis before midgut traversal. To determine whether nitric oxide and reactive oxygen species act as such triggers, ookinetes were cultured with donors of these molecules. Exposure to the nitric oxide donor SNP induced a significant increase in ookinetes with condensed nuclear chromatin, activated caspase-like molecules and translocation of phosphatidylserine that was dose and time related. Results from an assay that detects the potential-dependent accumulation of aggregates of JC-1 in mitochondria suggested that nitric oxide does not operate via loss of mitochondrial membrane potential. L-DOPA (reactive oxygen species donor) also caused apoptosis in a dose and time dependent manner. Removal of white blood cells significantly decreased ookinetes exhibiting a marker of apoptosis in vitro. Inhibition of the activity of nitric oxide synthase in the mosquito midgut epithelium using L-NAME significantly decreased the proportion of apoptotic ookinetes and increased the number of oocysts that developed. Introduction of a nitric oxide donor into the blood meal had no effect on mosquito longevity but did reduce prevalence and intensity of infection. Thus, nitric oxide and reactive oxygen species are triggers of apoptosis in Plasmodium ookinetes. They occur naturally in the mosquito midgut lumen, sourced from infected blood and mosquito tissue. Up regulation of mosquito nitric oxide synthase activity has potential as a transmission blocking strategy. PMID:20844583

  1. Differential susceptibility to colorectal cancer due to naturally occurring gut microbiota

    PubMed Central

    Ericsson, Aaron C.; Akter, Sadia; Hanson, Marina M.; Busi, Susheel B.; Parker, Taybor W.; Schehr, Rebecca J.; Hankins, Miriam A.; Ahner, Carin E.; Davis, Justin W.; Franklin, Craig L.; Amos-Landgraf, James M.; Bryda, Elizabeth C.

    2015-01-01

    Recent studies investigating the human microbiome have identified particular bacterial species that correlate with the presence of colorectal cancer. To evaluate the role of qualitatively different but naturally occurring gut microbiota and the relationship with colorectal cancer development, genetically identical embryos from the Polyposis in Rat Colon (Pirc) rat model of colorectal cancer were transferred into recipients of three different genetic backgrounds (F344/NHsd, LEW/SsNHsd, and Crl:SD). Tumor development in the pups was tracked longitudinally via colonoscopy, and end-stage tumor burden was determined. To confirm vertical transmission and identify associations between the gut microbiota and disease phenotype, the fecal microbiota was characterized in recipient dams 24 hours pre-partum, and in Pirc rat offspring prior to and during disease progression. Our data show that the gut microbiota varies between rat strains, with LEW/SsNHsd having a greater relative abundance of the bacteria Prevotella copri. The mature gut microbiota of pups resembled the profile of their dams, indicating that the dam is the primary determinant of the developing microbiota. Both male and female F344-Pirc rats harboring the Lewis microbiota had decreased tumor burden relative to genetically identical rats harboring F344 or SD microbiota. Significant negative correlations were detected between tumor burden and the relative abundance of specific taxa from samples taken at weaning and shortly thereafter, prior to observable adenoma development. Notably, this naturally occurring variation in the gut microbiota is associated with a significant difference in severity of colorectal cancer, and the abundance of certain taxa is associated with decreased tumor burden. PMID:26378041

  2. Localization of the Naturally Occurring Plasmid ColE1 at the Cell Pole?

    PubMed Central

    Yao, Shiyin; Helinski, Donald R.; Toukdarian, Aresa

    2007-01-01

    The naturally occurring plasmid ColE1 was found to localize as a cluster in one or both of the cell poles of Escherichia coli. In addition to the polar localization of ColE1 in most cells, movement of the plasmid to the midcell position was observed in time-lapse studies. ColE1 could be displaced from its polar location by the p15A replicon, pBAD33, but not by plasmid RK2. The displacement of ColE1 by pBAD33 resulted in an almost random positioning of ColE1 foci in the cell and also in a loss of segregational stability, as evidenced by the large number of cells carrying pBAD33 with no visible ColE1 focus and as confirmed by ColE1 stability studies. The addition of the active partitioning systems of the F plasmid (sopABC) or RK2 (OB1 incC korB) resulted in movement of the ColE1 replicon from the cell pole to within the nucleoid region. This repositioning did not result in destabilization but did result in an increase in the number of plasmid foci, most likely due to partial declustering. These results are consistent with the importance of par regions to the localization of plasmids to specific regions of the cell and demonstrate both localization and dynamic movement for a naturally occurring plasmid that does not encode a replication initiation protein or a partitioning system that is required for plasmid stability. PMID:17158664

  3. Urinary bladder cancer in dogs, a naturally occurring model for cancer biology and drug development.

    PubMed

    Knapp, Deborah W; Ramos-Vara, Jos A; Moore, George E; Dhawan, Deepika; Bonney, Patty L; Young, Kirsten E

    2014-01-01

    Each year more than 65,000 people are diagnosed with urinary bladder cancer, and more than 14,000 people die from the disease in the United States. Studies in relevant animal models are essential to improve the management of bladder cancer. Naturally occurring bladder cancer in dogs very closely mimics human invasive bladder cancer, specifically high-grade invasive transitional cell carcinoma (TCC; also referred to as invasive urothelial carcinoma) in cellular and molecular features; biological behavior, including sites and frequency of metastasis; and response to therapy. Canine bladder cancer complements experimentally induced rodent tumors in regard to animal models of bladder cancer. Results of cellular and molecular studies and -omics analyses in dogs are expected to lead to improved detection of TCC and preneoplastic lesions, earlier intervention, better prediction of patient outcome, and more effective TCC management overall. Studies in dogs are being used to help define heritable risks (through very strong breed-associated risk) and environment risks and to evaluate prevention and treatment approaches that benefit humans as well as dogs. Clinical treatment trials in pet dogs with TCC are considered a win-win scenario by clinician scientists and pet owners. The individual dog benefits from effective treatment, the results are expected to help other dogs, and the findings are expected to ultimately help humans with TCC. This article provides an overview of canine TCC, a summary of the similarities and differences between canine and human invasive TCC, and examples of the types of valuable translational research that can be done using dogs with naturally occurring TCC. PMID:24936033

  4. Making species salinity sensitivity distributions reflective of naturally occurring communities: using rapid testing and Bayesian statistics.

    PubMed

    Hickey, Graeme L; Kefford, Ben J; Dunlop, Jason E; Craig, Peter S

    2008-11-01

    Species sensitivity distributions (SSDs) may accurately predict the proportion of species in a community that are at hazard from environmental contaminants only if they contain sensitivity data from a large sample of species representative of the mix of species present in the locality or habitat of interest. With current widely accepted ecotoxicological methods, however, this rarely occurs. Two recent suggestions address this problem. First, use rapid toxicity tests, which are less rigorous than conventional tests, to approximate experimentally the sensitivity of many species quickly and in approximate proportion to naturally occurring communities. Second, use expert judgements regarding the sensitivity of higher taxonomic groups (e.g., orders) and Bayesian statistical methods to construct SSDs that reflect the richness (or perceived importance) of these groups. Here, we describe and analyze several models from a Bayesian perspective to construct SSDs from data derived using rapid toxicity testing, combining both rapid test data and expert opinion. We compare these new models with two frequentist approaches, Kaplan-Meier and a log-normal distribution, using a large data set on the salinity sensitivity of freshwater macroinvertebrates from Victoria (Australia). The frequentist log-normal analysis produced a SSD that overestimated the hazard to species relative to the Kaplan-Meier and Bayesian analyses. Of the Bayesian analyses investigated, the introduction of a weighting factor to account for the richness (or importance) of taxonomic groups influenced the calculated hazard to species. Furthermore, Bayesian methods allowed us to determine credible intervals representing SSD uncertainty. We recommend that rapid tests, expert judgements, and novel Bayesian statistical methods be used so that SSDs reflect communities of organisms found in nature. PMID:18522453

  5. Behavioral changes in freestall-housed dairy cows with naturally occurring clinical mastitis.

    PubMed

    Fogsgaard, K K; Bennedsgaard, T W; Herskin, M S

    2015-03-01

    Dairy cows exhibit classic signs of sickness behavior during mastitis. However, knowledge about the consequences of naturally occurring mastitis in freestall-housed dairy cows, milked in automatic milking systems, is lacking. The aim of the present study was to describe the behavior of dairy cows after diagnosis and antibiotic treatment of mastitis. In the days before and after antibiotic treatment, the milking behavior, feeding, and activity were examined in 30 mastitic and 30 control Danish Holstein-Friesian cows kept in freestalls and milked by an automatic milking system. Sickness behavior was evident in the mastitic dairy cows and local clinical signs in the udder as well as behavioral changes persisted beyond the 3 d of antibiotic treatment. In the days before diagnosis and treatment, feed intake was reduced compared with the control animals. Although reduced by the antibiotic treatment, this difference persisted until at least 10 d after diagnosis. Sick cows spent less time lying in the initial days after treatment, reversing to the level of the control cows within the 10 d posttreatment period. In the 48 h before antibiotic treatment, the mastitic cows showed increased restlessness during milking, as seen by a higher frequency of tripping and kicking. Mastitic cows continued to show increased kicking during milking even after the antibiotic treatment period. These results show that the behavioral changes induced by naturally occurring mastitis persisted beyond the days of antibiotic treatment, thereby calling for further investigation into management of mastitic dairy cows to optimize recovery and ensure animal welfare during the recovery period after clinical mastitis. PMID:25547306

  6. Naturally occurring marine brominated indoles are aryl hydrocarbon receptor ligands/agonists.

    PubMed

    DeGroot, Danica E; Franks, Diana G; Higa, Tatsuo; Tanaka, Junichi; Hahn, Mark E; Denison, Michael S

    2015-06-15

    The aryl hydrocarbon receptor (AhR) is a ligand-dependent transcription factor that mediates the toxic and biological effects of structurally diverse chemicals, including the environmental contaminant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). As part of a larger effort to identify the full spectrum of chemicals that can bind to and activate the AhR, we have examined the ability of several naturally occurring marine-derived brominated indoles and brominated (methylthio)indoles (collectively referred to as brominated indoles) to bind to the AhR and stimulate AhR-dependent gene expression. Incubation of mouse, rat, and guinea pig recombinant cell lines containing a stably transfected AhR-responsive luciferase reporter gene with eight brominated indoles revealed that all compounds stimulated luciferase reporter gene activity, although some species-specific differences were observed. All compounds induced significantly more luciferase activity when incubated with cells for 4 h as compared to 24 h, demonstrating that these compounds are transient activators of the AhR signaling pathway. Three of the brominated indoles induced CYP1A1 mRNA in human HepG2 cells in vitro and Cyp1a mRNA in zebrafish embryos in vivo. The identification of the brominated indoles as direct ligands and activators/agonists of the AhR was confirmed by their ability to compete with [(3)H]TCDD for binding to the AhR and to stimulate AhR transformation and DNA binding in vitro. Taken together, these results indicate that marine-derived brominated indoles are members of a new class of naturally occurring AhR agonists. PMID:26001051

  7. Naturally occurring radioactive material (NORM) from a former phosphoric acid processing plant.

    PubMed

    Beddow, H; Black, S; Read, D

    2006-01-01

    In recent years there has been an increasing awareness of the radiological impact of non-nuclear industries that extract and/or process ores and minerals containing naturally occurring radioactive material (NORM). These industrial activities may result in significant radioactive contamination of (by-) products, wastes and plant installations. In this study, scale samples were collected from a decommissioned phosphoric acid processing plant. To determine the nature and concentration of NORM retained in pipe-work and associated process plant, four main areas of the site were investigated: (1) the 'Green Acid Plant', where crude acid was concentrated; (2) the green acid storage tanks; (3) the Purified White Acid (PWA) plant, where inorganic impurities were removed; and (4) the solid waste, disposed of on-site as landfill. The scale samples predominantly comprise the following: fluorides (e.g. ralstonite); calcium sulphate (e.g. gypsum); and an assemblage of mixed fluorides and phosphates (e.g. iron fluoride hydrate, calcium phosphate), respectively. The radioactive inventory is dominated by 238U and its decay chain products, and significant fractionation along the series occurs. Compared to the feedstock ore, elevated concentrations (< or =8.8 Bq/g) of 238U were found to be retained in installations where the process stream was rich in fluorides and phosphates. In addition, enriched levels (< or =11 Bq/g) of 226Ra were found in association with precipitates of calcium sulphate. Water extraction tests indicate that many of the scales and waste contain significantly soluble materials and readily release radioactivity into solution. PMID:16303218

  8. Naturally Occurring Capsid Protein Variants of Human Papillomavirus Genotype 31 Represent a Single L1 Serotype

    PubMed Central

    Bissett, Sara L.; Godi, Anna; Fleury, Maxime J. J.; Touze, Antoine; Cocuzza, Clementina

    2015-01-01

    ABSTRACT We investigated naturally occurring variation within the major (L1) and minor (L2) capsid proteins of oncogenic human papillomavirus (HPV) genotype 31 (HPV31) to determine the impact on capsid antigenicity. L1L2 pseudoviruses (PsVs) representing the three HPV31 variant lineages, variant lineages A, B, and C, exhibited comparable particle-to-infectivity ratios and morphologies. Lineage-specific L1L2 PsVs demonstrated subtle differences in susceptibility to neutralization by antibodies elicited following vaccination or preclinical L1 virus-like particle (VLP) immunization or by monoclonal antibodies; however, these differences were generally of a low magnitude. These data indicate that the diagnostic lineage-specific single nucleotide polymorphisms within the HPV31 capsid genes have a limited effect on L1 antibody-mediated neutralization and that the three HPV31 variant lineages belong to a single L1 serotype. These data contribute to our understanding of HPV L1 variant antigenicity. IMPORTANCE The virus coat (capsid) of the human papillomavirus contains major (L1) and minor (L2) capsid proteins. These proteins facilitate host cell attachment and viral infectivity and are the targets for antibodies which interfere with these events. In this study, we investigated the impact of naturally occurring variation within these proteins upon susceptibility to viral neutralization by antibodies induced by L1 VLP immunization. We demonstrate that HPV31 L1 and L2 variants exhibit similar susceptibility to antibody-mediated neutralization and that for the purposes of L1 VLP-based vaccines, these variant lineages represent a single serotype. PMID:25995264

  9. Analysis of naturally-occurring radionuclides in coal combustion fly ash, gypsum, and scrubber residue samples.

    PubMed

    Roper, Angela R; Stabin, Michael G; Delapp, Rossane C; Kosson, David S

    2013-03-01

    Coal combustion residues from coal-fired power plants can be advantageous for use in building and construction materials. These by-products contain trace quantities of naturally occurring radionuclides from the uranium and thorium series, as well as other naturally occurring radionuclides such as K. Analysis was performed on samples of coal fly ash, flue gas desulfurization, gypsum and scrubber sludges, fixated scrubber sludges, and waste water filter cakes sampled from multiple coal-fired power plants in the United States. The radioactive content of U and Th decay series nuclides was determined using gamma photopeaks from progeny Pb at 352 keV and Tl at 583 keV, respectively; K specific activities were determined using the 1,461 keV photopeak. The samples were hermetically sealed to allow for secular equilibrium between the radium parents and the radon and subsequent progeny. Samples were analyzed in a common geometry using two high purity germanium photon detectors with low energy detection capabilities. The specific activities (Bq kg) were compared to results from literature studies including different building materials and fly ash specific activities. Fly ash from bituminous and subbituminous coals had U specific activities varying from 30-217 Bq kg (mean + 1 s.d. 119 ± 45 Bq kg) and 72-209 Bq kg (115 ± 40 Bq kg), respectively; Th specific activities from 10-120 Bq kg (73 ± 26 Bq kg) and 53-110 Bq kg (81 ± 18 Bq kg), respectively; and K specific activities from 177 to 928 Bq kg (569 ± 184 Bq kg) and 87-303 Bq kg (171 ± 69 Bq kg), respectively. Gypsum samples had U, Th, and K specific activities approximately one order of magnitude less than measured for fly ash samples. PMID:23361421

  10. Biased Signaling in Naturally Occurring Mutations in Human Melanocortin-3 Receptor Gene

    PubMed Central

    Yang, Fan; Huang, Hui; Tao, Ya-Xiong

    2015-01-01

    The melanocortin-3 receptor (MC3R) is primarily expressed in the hypothalamus and plays an important role in the regulation of energy homeostasis. Recently, some studies demonstrated that MC3R also signals through mitogen-activated protein kinases (MAPKs), especially extracellular signal-regulated kinases 1 and 2 (ERK1/2). ERK1/2 signaling is known to alter gene expression, potentially contributing to the prolonged action of melanocortins on energy homeostasis regulation. In the present study, we performed detailed functional studies on 8 novel naturally occurring MC3R mutations recently reported, and the effects of endogenous MC3R agonist, ?-melanocyte stimulating hormone (MSH), on ERK1/2 signaling on all 22 naturally occurring MC3R mutations reported to date. We found that mutants D158Y and L299V were potential pathogenic causes to obesity. Four residues, F82, D158, L249 and L299, played critical roles in different aspects of MC3R function. ?-MSH exhibited balanced activity in Gs-cAMP and ERK1/2 signaling pathways in 15 of the 22 mutant MC3Rs. The other 7 mutant MC3Rs were biased to either one of the signaling pathways. In summary, we provided novel data about the structure-function relationship of MC3R, identifying residues important for receptor function. We also demonstrated that some mutations exhibited biased signaling, preferentially activating one intracellular signaling pathway, adding a new layer of complexity to MC3R pharmacology. PMID:25798062

  11. Characterization of naturally-occurring humoral immunity to AAV in sheep.

    PubMed

    Tellez, Joseph; Van Vliet, Kim; Tseng, Yu-Shan; Finn, Jonathan D; Tschernia, Nick; Almeida-Porada, Graa; Arruda, Valder R; Agbandje-McKenna, Mavis; Porada, Christopher D

    2013-01-01

    AAV vectors have shown great promise for clinical gene therapy (GT), but pre-existing human immunity against the AAV capsid often limits transduction. Thus, testing promising AAV-based GT approaches in an animal model with similar pre-existing immunity could better predict clinical outcome. Sheep have long been used for basic biological and preclinical studies. Moreover, we have re-established a line of sheep with severe hemophilia A (HA). Given the impetus to use AAV-based GT to treat hemophilia, we characterized the pre-existing ovine humoral immunity to AAV. ELISA revealed naturally-occurring antibodies to AAV1, AAV2, AAV5, AAV6, AAV8, and AAV9. For AAV2, AAV8, and AAV9 these inhibit transduction in a luciferase-based neutralization assay. Epitope mapping identified peptides that were common to the capsids of all AAV serotypes tested (AAV2, AAV5, AAV8 and AAV9), with each animal harboring antibodies to unique and common capsid epitopes. Mapping using X-ray crystallographic AAV capsid structures demonstrated that these antibodies recognized both surface epitopes and epitopes located within regions of the capsid that are internal or buried in the capsid structure. These results suggest that sheep harbor endogenous AAV, which induces immunity to both intact capsid and to capsid epitopes presented following proteolysis during the course of infection. In conclusion, their clinically relevant physiology and the presence of naturally-occurring antibodies to multiple AAV serotypes collectively make sheep a unique model in which to study GT for HA, and other diseases, and develop strategies to circumvent the clinically important barrier of pre-existing AAV immunity. PMID:24086458

  12. ENVIRONMENTAL ISOTOPES FOR RESOLUTION OF HYDROLOGY PROBLEMS

    EPA Science Inventory

    The use of environmental isotopes as tracers in the hydrosphere is increasing as analytical instrumentation improves and more applications are discovered. There exists still misconceptions on the role of isotopes in resolving hydrology problems. Naturally occurring isotopes in th...

  13. Naturally Occurring Mutations in the MPS1 Gene Predispose Cells to Kinase Inhibitor Drug Resistance.

    PubMed

    Gurden, Mark D; Westwood, Isaac M; Faisal, Amir; Naud, Sbastien; Cheung, Kwai-Ming J; McAndrew, Craig; Wood, Amy; Schmitt, Jessica; Boxall, Kathy; Mak, Grace; Workman, Paul; Burke, Rosemary; Hoelder, Swen; Blagg, Julian; Van Montfort, Rob L M; Linardopoulos, Spiros

    2015-08-15

    Acquired resistance to therapy is perhaps the greatest challenge to effective clinical management of cancer. With several inhibitors of the mitotic checkpoint kinase MPS1 in preclinical development, we sought to investigate how resistance against these inhibitors may arise so that mitigation or bypass strategies could be addressed as early as possible. Toward this end, we modeled acquired resistance to the MPS1 inhibitors AZ3146, NMS-P715, and CCT251455, identifying five point mutations in the kinase domain of MPS1 that confer resistance against multiple inhibitors. Structural studies showed how the MPS1 mutants conferred resistance by causing steric hindrance to inhibitor binding. Notably, we show that these mutations occur in nontreated cancer cell lines and primary tumor specimens, and that they also preexist in normal lymphoblast and breast tissues. In a parallel piece of work, we also show that the EGFR p.T790M mutation, the most common mutation conferring resistance to the EGFR inhibitor gefitinib, also preexists in cancer cells and normal tissue. Our results therefore suggest that mutations conferring resistance to targeted therapy occur naturally in normal and malignant cells and these mutations do not arise as a result of the increased mutagenic plasticity of cancer cells. PMID:26202014

  14. P-Element repression in Drosophila melanogaster by a naturally occurring defective telomeric P copy.

    PubMed

    Marin, L; Lehmann, M; Nouaud, D; Izaabel, H; Anxolabhre, D; Ronsseray, S

    2000-08-01

    In Drosophila melanogaster, hybrid dysgenesis occurs in progeny from crosses between females lacking P elements and males carrying P elements scattered throughout the genome. We have genetically isolated a naturally occurring P insertion at cytological location 1A, from a Tunisian population. The Nasr'Allah-P(1A) element [NA-P(1A)] has a deletion of the first 871 bp including the P promoter. It is flanked at the 3' end by telomeric associated sequences and at the 5' end by a HeT-A element sequence. The NA-P(1A) element strongly represses dysgenic sterility and P transposition. However, when testing P-promoter repression, NA-P(1A) was unable to repress a germinally expressed P-lacZ construct bearing no 5'-homology with it. Conversely, a second P-lacZ construct, in which the fusion with lacZ takes place in exon 3 of P, was successfully repressed by NA-P(1A). This suggests that NA-P(1A) repression involves a homology-dependent component. PMID:10924479

  15. A Naturally Occurring Bovine Tauopathy Is Geographically Widespread in the UK

    PubMed Central

    Jeffrey, Martin; Piccardo, Pedro; Ritchie, Diane L.; Ironside, James W.; Green, Alison J. E.; McGovern, Gillian

    2015-01-01

    Many human neurodegenerative diseases are associated with hyperphosphorylation and widespread intra-neuronal and glial associated aggregation of the microtubule associated protein tau. In contrast, animal tauopathies are not reported with only senescent animals showing inconspicuous tau labelling of fine processes albeit significant tau aggregation may occur in some experimental animal disease. Since 1986, an idiopathic neurological condition of adult cattle has been recognised in the UK as a sub-set of cattle slaughtered as suspect bovine spongiform encephalopathy cases. This disorder is characterised by brainstem neuronal chromatolysis and degeneration with variable hippocampal sclerosis and spongiform change. Selected cases of idiopathic brainstem neuronal chromatolysis (IBNC) were identified from archive material and characterised using antibodies specific to several tau hyperphosphorylation sites or different isoforms of the tau microtubule binding region. Labelling was also carried out for alpha synuclein, ubiquitin, TDP43, Aβ1–42, Aβ1–40. Widespread tau labelling was identified in all IBNC brains examined and with each of seven tau antibodies recognising different hyperphosphorylated sites. Labelling with each antibody was associated with dendrites, neuronal perikarya and glia. Thus IBNC is a sporadic, progressive neurological disease predominantly affecting aged cattle that occurs throughout the UK and is associated with hyperphosphorylation of tau, a rare example of a naturally-occurring tauopathy in a non-primate species. Secondary accumulation of alpha synuclein and ubiquitin was also present. The neuropathology does not precisely correspond with any human tauopathy. The cause of IBNC remains undetermined but environmental factors and exposure to agrochemicals needs to be considered in future aetiological investigations. PMID:26091261

  16. A Naturally Occurring Bovine Tauopathy Is Geographically Widespread in the UK.

    PubMed

    Jeffrey, Martin; Piccardo, Pedro; Ritchie, Diane L; Ironside, James W; Green, Alison J E; McGovern, Gillian

    2015-01-01

    Many human neurodegenerative diseases are associated with hyperphosphorylation and widespread intra-neuronal and glial associated aggregation of the microtubule associated protein tau. In contrast, animal tauopathies are not reported with only senescent animals showing inconspicuous tau labelling of fine processes albeit significant tau aggregation may occur in some experimental animal disease. Since 1986, an idiopathic neurological condition of adult cattle has been recognised in the UK as a sub-set of cattle slaughtered as suspect bovine spongiform encephalopathy cases. This disorder is characterised by brainstem neuronal chromatolysis and degeneration with variable hippocampal sclerosis and spongiform change. Selected cases of idiopathic brainstem neuronal chromatolysis (IBNC) were identified from archive material and characterised using antibodies specific to several tau hyperphosphorylation sites or different isoforms of the tau microtubule binding region. Labelling was also carried out for alpha synuclein, ubiquitin, TDP43, Aβ 1-42, Aβ 1-40. Widespread tau labelling was identified in all IBNC brains examined and with each of seven tau antibodies recognising different hyperphosphorylated sites. Labelling with each antibody was associated with dendrites, neuronal perikarya and glia. Thus IBNC is a sporadic, progressive neurological disease predominantly affecting aged cattle that occurs throughout the UK and is associated with hyperphosphorylation of tau, a rare example of a naturally-occurring tauopathy in a non-primate species. Secondary accumulation of alpha synuclein and ubiquitin was also present. The neuropathology does not precisely correspond with any human tauopathy. The cause of IBNC remains undetermined but environmental factors and exposure to agrochemicals needs to be considered in future aetiological investigations. PMID:26091261

  17. Acoustic surface perception from naturally occurring step sounds of a dexterous hexapod robot

    NASA Astrophysics Data System (ADS)

    Cuneyitoglu Ozkul, Mine; Saranli, Afsar; Yazicioglu, Yigit

    2013-10-01

    Legged robots that exhibit dynamic dexterity naturally interact with the surface to generate complex acoustic signals carrying rich information on the surface as well as the robot platform itself. However, the nature of a legged robot, which is a complex, hybrid dynamic system, renders the more common approach of model-based system identification impractical. The present paper focuses on acoustic surface identification and proposes a non-model-based analysis and classification approach adopted from the speech processing literature. A novel feature set composed of spectral band energies augmented by their vector time derivatives and time-domain averaged zero crossing rate is proposed. Using a multi-dimensional vector classifier, these features carry enough information to accurately classify a range of commonly occurring indoor and outdoor surfaces without using of any mechanical system model. A comparative experimental study is carried out and classification performance and computational complexity are characterized. Different feature combinations, classifiers and changes in critical design parameters are investigated. A realistic and representative acoustic data set is collected with the robot moving at different speeds on a number of surfaces. The study demonstrates promising performance of this non-model-based approach, even in an acoustically uncontrolled environment. The approach also has good chance of performing in real-time.

  18. Identification of naturally occurring hybrids between two overexploited sciaenid species along the South African coast.

    PubMed

    Mirimin, L; Kerwath, S E; Macey, B M; Bester-van der Merwe, A E; Lamberth, S J; Bloomer, P; Roodt-Wilding, R

    2014-07-01

    Hybridisation between fish species can play a significant role in evolutionary processes and can influence management and conservation planning, however, this phenomenon has been widely understudied, especially in marine organisms. The distribution limits of two sciaenid species (silver kob, Argyrosomus inodorus, and dusky kob, A. japonicus) partly overlap along the South African coast, where both species have undergone severe depletion due to overfishing. Following the identification of a number of possible cases of species misidentification or hybridisation (21 out of 422 individuals), nuclear and mitochondrial DNA data (12microsatellite loci and 562bp of the COI gene) were analysed to investigate the genetic composition of these individuals. Results indicated a field-based species misidentification rate of approximately 2.8% and a rate of natural hybridisation of 0.7%. Interestingly, all hybrid fish resulted from first-generation (F1) hybridisation events, which occurred exclusively between silver kob females and dusky kob males. Whether hybridisation is the result of natural events (such as secondary contact following a shift in distribution range), or anthropogenic activities (size-selective pressure due to overfishing), these findings have important implications for critical recovery and future management of these species in the wild. PMID:24582737

  19. In vitro Conversion of Vinyl to Formyl Groups in Naturally Occurring Chlorophylls

    PubMed Central

    Loughlin, Patrick C.; Willows, Robert D.; Chen, Min

    2014-01-01

    The chemical structural differences distinguishing chlorophylls in oxygenic photosynthetic organisms are either formyl substitution (chlorophyll b, d, and f) or the degree of unsaturation (8-vinyl chlorophyll a and b) of a side chain of the macrocycle compared with chlorophyll a. We conducted an investigation of the conversion of vinyl to formyl groups among naturally occurring chlorophylls. We demonstrated the in vitro oxidative cleavage of vinyl side groups to yield formyl groups through the aid of a thiol-containing compound in aqueous reaction mixture at room temperature. Heme is required as a catalyst in aqueous solution but is not required in methanolic reaction mixture. The conversion of vinyl- to formyl- groups is independent of their position on the macrocycle, as we observed oxidative cleavages of both 3-vinyl and 8-vinyl side chains to yield formyl groups. Three new chlorophyll derivatives were synthesised using 8-vinyl chlorophyll a as substrate: 8-vinyl chlorophyll d, [8-formyl]-chlorophyll a, and [3,8-diformyl]-chlorophyll a. The structural and spectral properties will provide a signature that may aid in identification of the novel chlorophyll derivatives in natural systems. The ease of conversion of vinyl- to formyl- in chlorophylls demonstrated here has implications regarding the biosynthetic mechanism of chlorophyll d in vivo. PMID:25119484

  20. A naturally occurring gene amplification leading to sulfonamide and trimethoprim resistance in Streptococcus agalactiae.

    PubMed

    Brochet, Mathieu; Couvé, Elisabeth; Zouine, Mohamed; Poyart, Claire; Glaser, Philippe

    2008-01-01

    Gene amplifications have been detected as a transitory phenomenon in bacterial cultures. They are predicted to contribute to rapid adaptation by simultaneously increasing the expression of genes clustered on the chromosome. However, genome amplifications have rarely been described in natural isolates. Through DNA array analysis, we have identified two Streptococcus agalactiae strains carrying tandem genome amplifications: a fourfold amplification of 13.5 kb and a duplication of 92 kb. Both amplifications were located close to the terminus of replication and originated independently from any long repeated sequence. They probably arose in the human host and showed different stabilities, the 13.5-kb amplification being lost at a frequency of 0.003 per generation and the 92-kb tandem duplication at a frequency of 0.035 per generation. The 13.5-kb tandem amplification carried the five genes required for dihydrofolate biosynthesis and led to both trimethoprim (TMP) and sulfonamide (SU) resistance. Resistance to SU probably resulted from the increased synthesis of dihydropteroate synthase, the target of this antibiotic, whereas the amplification of the whole pathway was responsible for TMP resistance. This revealed a new mechanism of resistance to TMP involving an increased dihydrofolate biosynthesis. This is, to our knowledge, the first reported case of naturally occurring antibiotic resistance resulting from genome amplification in bacteria. The low stability of DNA segment amplifications suggests that their role in antibiotic resistance might have been underestimated. PMID:18024520

  1. A Naturally Occurring Gene Amplification Leading to Sulfonamide and Trimethoprim Resistance in Streptococcus agalactiae▿

    PubMed Central

    Brochet, Mathieu; Couvé, Elisabeth; Zouine, Mohamed; Poyart, Claire; Glaser, Philippe

    2008-01-01

    Gene amplifications have been detected as a transitory phenomenon in bacterial cultures. They are predicted to contribute to rapid adaptation by simultaneously increasing the expression of genes clustered on the chromosome. However, genome amplifications have rarely been described in natural isolates. Through DNA array analysis, we have identified two Streptococcus agalactiae strains carrying tandem genome amplifications: a fourfold amplification of 13.5 kb and a duplication of 92 kb. Both amplifications were located close to the terminus of replication and originated independently from any long repeated sequence. They probably arose in the human host and showed different stabilities, the 13.5-kb amplification being lost at a frequency of 0.003 per generation and the 92-kb tandem duplication at a frequency of 0.035 per generation. The 13.5-kb tandem amplification carried the five genes required for dihydrofolate biosynthesis and led to both trimethoprim (TMP) and sulfonamide (SU) resistance. Resistance to SU probably resulted from the increased synthesis of dihydropteroate synthase, the target of this antibiotic, whereas the amplification of the whole pathway was responsible for TMP resistance. This revealed a new mechanism of resistance to TMP involving an increased dihydrofolate biosynthesis. This is, to our knowledge, the first reported case of naturally occurring antibiotic resistance resulting from genome amplification in bacteria. The low stability of DNA segment amplifications suggests that their role in antibiotic resistance might have been underestimated. PMID:18024520

  2. Naturally occurring double-stranded RNA and immune responses. III. Immunogenicity and antigenicity in animals.

    PubMed Central

    Cunningham, P G; Naysmith, J D

    1975-01-01

    Naturally occurring, double-stranded RNA (ds-RNA)) was immunogenic when injected into mice, rats, guinea-pigs, rabbits, dogs and baboons. The response to native material administered intravenously (i.v.) was strongest in rabbits and mice, and weakest in baboons. Mice, guinea-pigs and baboons injected with ds-RNA complexed with methylated BSA emulsified in Freund's complete adjuvant all gave high antibody responses. When ds-RNA was given in aerosol form to mice and guinea-pigs the response was weaker than that following i.v. injection, and baboons did not respond to antigen given as an aerosol. In most species the immune response obtained was predominantly IgM in nature, and there was no evidence for cell-mediated immunity in any species. The only evidence of an adverse reaction associated with repeated administration of ds-RNA was a systemic anaphylactic-type response in a small group of mice given ds-RNA repeatedly in aerosol form and challenged with ds-RNA i.v. PMID:811555

  3. Naturally Occurring Radioactivity in the City and Across Near by Cities in Iran

    NASA Astrophysics Data System (ADS)

    Hosseini, S. A.

    Naturally Occurring Radioactive Material (NORM) could be contributed in radioactivity pollution of environment. The natural radioactivity concentration in soil, drinking water, certain food items samples of Zahedan city in Iran and absorbed dose across near by 5 Sistan and Blouchestan cities in Iran have been determined using gamma spectrometry and Multi Rad Low Level (MRLL) detector, respectively. Results show that the concentrations of 40K, 238U and 232Th in the samples of the city varied from 39638.4 to 57657.4 Bq kg-1 with a mean of 473.340.7 Bq kg-1 for 40K, whereas for 238U and 232Th values varied from 20.62.3 to 24.73.6 Bq kg-1 with a mean of 21.92.8 Bq kg-1 and from 28.93.3 to 36.53.6 Bq kg-1 with a mean of 333.7 Bq kg-1, respectively. The absorbed dose rate in the air across Zahedan cities border ranged between 165 nGy h-1and 30044 nGy h-1 and the gross mean was 158.024.5 nGy h-1. It can be concluded that no risk threat the residents around and center Zahedan city and in above mentioned border.

  4. Allelopathic properties of ?-terthienyl and phenylheptatriyne, naturally occurring compounds from species of asteraceae.

    PubMed

    Campbell, G; Lambert, J D; Arnason, T; Towers, G H

    1982-06-01

    Alpha-terthienyl (?-T), a naturally occurring polyacetylene derivative from roots ofTagetes erecta L., and phenylheptatriyne (PHT), from leaves ofBidens pilosa L., were tested as possible allelopathic agents against four seedling species (Asclepias syriaca L.,Chenopodium album L.,Phleum pratense L.,Trifolium pratense L.).Asclepias was the most sensitive of the species. Allelopathic activity was enhanced in the presence of sunlight or sources of near-UV, with LC50s forA. syriaca of 0.15 ppm and 0.66 ppm with ?-T and PHT, respectively; 0.27 and 0.85 forC. album; 0.79 and 1.43 forP. pratense, and 1.93 and 1.82 forT. pratense. Near-UV exposure was saturating but never more than found in summer sunlight at Ottawa, Canada. Growth inhibition was observed with seedlings treated with ?-T and PHT but without near-UV irradiation. Germination of seedlings was also sensitive to ?-T and PHT with or without near-UV treatment. ?-T was extracted from soil surrounding the roots ofTagetes. Concentrations calculated for the soil (0.4 ppm) indicate that seedling growth could be significantly hindered. The activity and specificity of ?-T was sufficiently high to warrant future field trials to assess its potential as a natural weed-control agent. PMID:24415251

  5. Aberrant wound healing in the horse: naturally occurring conditions reminiscent of those observed in man.

    PubMed

    Theoret, Christine L; Wilmink, Jacintha M

    2013-01-01

    Impaired wound healing represents an enormous clinical and financial problem for companion animals and humans alike. Unfortunately, most models used to study healing rely on rodents, which have significant differences in the healing and scarring process and rarely develop complications. In order to better simulate impaired healing, the model should strive to reproduce the natural processes of healing and delayed healing. Wounds on the limbs of horses display similarities to wounds in humans in their epithelialization/contraction ratio, genetic influence as well as dysregulated cytokine profile and the spontaneous development of fibroproliferative disorders. Veterinarians have access to advanced wound therapies that are often identical to those provided to human patients. Wound research in large animals has resulted in new wound models as well as a better understanding of the physiology, immunology, and local environmental impact on both normal and aberrant wound healing. One such model reproduces the naturally occurring fibroproliferative disorder of horses known as exuberant granulation tissue. Comparisons between the normally healing and impaired wounds provide insight into the repair process and can facilitate product development. A better understanding of the wound healing physiopathology based on clinically accurate animal models should lead to the development of novel therapies thereby improving outcomes in both human and veterinary patients. PMID:23441750

  6. Phosphate removal from wastewaters by a naturally occurring, calcium-rich sepiolite.

    PubMed

    Yin, Hongbin; Yun, Ye; Zhang, Yinlong; Fan, Chengxin

    2011-12-30

    Developing an easily handled and cost-effective phosphate absorbent is crucial for the control of water eutrophication. In this study, a naturally occurring, calcium-rich sepiolite (NOCS) was evaluated for its feasibility as a phosphate absorbent candidate. Batch studies showed that phosphate sorption on NOCS followed a stepwise isotherm for concentrations between 5 and 1000 mg P/l, and the phosphate sorption was fitted well by the Freundlich equation. The estimated maximum phosphorus sorption capacity was 32.0 mg P/g, which was quite high compared with other natural materials and was comparable to some efficient manmade P absorbents. The NOCS sorption kinetics followed a pseudo-first-order model with an R(2) value of 0.999. The adsorption of phosphate was highly pH dependent. Phosphate adsorption decreased moderately with increasing pH values from 3.0 to 6.0, and it decreased sharply in alkaline conditions. Ionic strength, sulfate, nitrate and chloride anions had no effects on the phosphate removal capacity of NOCS, but fluoride and bicarbonate anions exerted large effects. Phosphorus fractionation indicated that phosphate removed from the solution was primarily formed as a calcium-bound phosphorus precipitation, which was further confirmed by SEM-EDS analysis. Moreover, phosphate was barely (<1.5%) desorbed from the phosphorus-adsorbed sepiolite regardless of pH value. PMID:22088501

  7. Enrichment and particle size dependence of polonium and other naturally occurring radionuclides in coal ash.

    PubMed

    Sahu, S K; Tiwari, M; Bhangare, R C; Pandit, G G

    2014-12-01

    Coal fired thermal power contributes 70% of power in India. Coal fired power generation results in huge amounts of fly ash and bottom ash of varying properties. Coal, which contains the naturally occurring radionuclides, on burning results in enrichment of these radionuclides in the ashes. In the present study, coal, bottom ash and fly ash samples collected from six coal-fired power plants in India were measured for (210)Po using alpha spectrometry and for natural U, (226)Ra, (232)Th and (40)K by an HPGe γ-ray spectrometer. (210)Po in fly ash ranged from 25.7 to 70 Bq/kg with a mean value of 40.5 Bq/kg. The range and mean activities of (238)U, (226)Ra, (232)Th, (40)K in fly ash were 38.5-101 (78.1), 60-105.7 (79), 20-125 (61.7) and 43.6-200 (100) Bq/kg respectively. Fly ash and bottom ash contains two to five times more natural radionuclides than feed coal. The results were compared with the available data from earlier studies in other countries. The effect of particle size on enrichment factor of the nuclides in fly ash was studied. (210)Po showed the largest size dependence with its concentration favoring the smaller particle size while (232)Th showed least size dependence. (238)U and (226)Ra showed behavior intermediate to that of (210)Po and (232)Th. Also the correlation between sulfur content of the feed coal and activity of (210)Po was investigated. Increased sulfur content in feed coal enhanced enrichment of (210)Po in ash. PMID:24813148

  8. Levels of naturally occurring gamma radiation measured in British homes and their prediction in particular residences.

    PubMed

    Kendall, G M; Wakeford, R; Athanson, M; Vincent, T J; Carter, E J; McColl, N P; Little, M P

    2016-03-01

    Gamma radiation from natural sources (including directly ionising cosmic rays) is an important component of background radiation. In the present paper, indoor measurements of naturally occurring gamma rays that were undertaken as part of the UK Childhood Cancer Study are summarised, and it is shown that these are broadly compatible with an earlier UK National Survey. The distribution of indoor gamma-ray dose rates in Great Britain is approximately normal with mean 96 nGy/h and standard deviation 23 nGy/h. Directly ionising cosmic rays contribute about one-third of the total. The expanded dataset allows a more detailed description than previously of indoor gamma-ray exposures and in particular their geographical variation. Various strategies for predicting indoor natural background gamma-ray dose rates were explored. In the first of these, a geostatistical model was fitted, which assumes an underlying geologically determined spatial variation, superimposed on which is a Gaussian stochastic process with Matérn correlation structure that models the observed tendency of dose rates in neighbouring houses to correlate. In the second approach, a number of dose-rate interpolation measures were first derived, based on averages over geologically or administratively defined areas or using distance-weighted averages of measurements at nearest-neighbour points. Linear regression was then used to derive an optimal linear combination of these interpolation measures. The predictive performances of the two models were compared via cross-validation, using a randomly selected 70 % of the data to fit the models and the remaining 30 % to test them. The mean square error (MSE) of the linear-regression model was lower than that of the Gaussian-Matérn model (MSE 378 and 411, respectively). The predictive performance of the two candidate models was also evaluated via simulation; the OLS model performs significantly better than the Gaussian-Matérn model. PMID:26880257

  9. Naturally occurring clay nanoparticles in Latosols of Brazil central region: detection and characterization

    NASA Astrophysics Data System (ADS)

    Dominika Dybowska, Agnieszka; Luciene Maltoni, Katia; Piella, Jordi; Najorka, Jens; Puntes, Victor; Valsami-Jones, Eugenia

    2015-04-01

    Stability and reactivity of minerals change as a particle size function, which makes mineral nanoparticles (defined here as <100 nm) fundamentally distinct from the larger size materials. Naturally occurring mineral nanoparticles contribute to many biogeochemical processes, however much remains to be learnt about these materials, their size dependent behavior and environmental significance. Advances in analytical, imaging and spectroscopic techniques made it now possible to study such particles; however we still have limited knowledge of their chemical, structural and morphological identity and reactivity, in particular in soils. The aim of this research was to characterize the naturally occurring nanoparticles in three soils from Brazil central region. The samples were collected in the A horizon, treated with H2O2 to remove organic material, dispersed in ultrasonic bath and wet sieved (53 µm) to remove the sand fraction. The clay fraction was collected by siphoning the supernatant, conditioned in 1000 ml cylinder, according to the Stock's law. This fraction was further processed by re-suspension in water, sonication and repeated centrifugation, to separate the fraction smaller than 100nm. This material, called here the soil "nanofraction", was analyzed using a range of techniques: 1) nanoparticle size/morphology and crystallinity with Transmission Electron Microscopy (TEM operateing in scanning (HAADF-STEM) and High Resolution (HRTEM) mode), 2) size distribution in water with Dynamic Light Scattering (DLS) and surface charge estimated from electrophoretic mobility measurements 3) crystal phase and crystallite size with X-ray Diffraction (XRD) 4) Chemical composition by quantitative analysis of elements (e.g., Si, Fe, Al, Ti) and their spatial distribution with HRTEM/EDS elemental mappings. The nanofraction had an average hydrodynamic particle diameter ranging from 83 to 92nm with a low polydispersity index of 0.13-0.17 and was found highly stable in aqueous suspension (no change in average particle size up to several months of storage). Particle surface charge (in water) ranged from -31mV to -34.5mV (pH = 5.7 - 6.2), this reflects the predominantly negative surface charge of kaolinites in soil environment effectively screening the positive charge of Fe oxides. Kaolinites appeared as single crystals (pseudo hexagonal platelets) while Fe oxides occurred mostly as micro-aggregates, with individual particles often not morphologically distinct with particle size <10nm. In addition, several anatase (TiO2) nanoparticles were also found. Both kaolinites and Fe oxides nanoparticles were crystalline, as evidenced from XRD measurements and HRTEM imaging. Distinction between different crystalline forms of Fe oxides (mainly hematite and goethite) was only possible with XRD, which revealed also subtle differences in mineralogical composition of the clay fraction (<2µm) and nanofraction (<100nm). The kaolinite's crystallite size (calculated from XRD data) was found to range 14-17nm in the nanofraction and 26-50nm in the clay fraction. For hematite, it was 13nm in the nanofraction and ranged from 21-30nm in the clay fraction. Such small particles can be expected to play an important role in soil sorption processes with implications on nutrient and contaminant cycling. Identification and understanding of the properties of naturally occurring nanoparticles in soils can therefore help soil scientists to better understand retention/mobilization of nutrients and pollutants in soils.

  10. The kinetics of clumped-isotope reactions in calcite and apatite from natural and experimental samples

    NASA Astrophysics Data System (ADS)

    Stolper, D. A.; Eiler, J. M.

    2014-12-01

    Measurements of clumped isotopes of carbonate-bearing minerals are a powerful tool for reconstructing past surface temperatures and thermal histories of shallow crustal rocks. Because the clumped-isotope thermometer is based on homogenous-phase equilibrium, a sample's clumped-isotope temperature is susceptible to resetting through, for example, intracrystalline diffusion and redistribution of C and O isotopes during (re)heating or slow cooling. Quantitative knowledge of the kinetics of this resetting have received increasing attention (1-3) and is critical for understanding the meaning of clumped-isotope temperatures of samples with complex burial histories. To better constrain these kinetics and complement previous work (1-3) we performed heating experiments (400-700°C) on optical calcites and carbonate-bearing apatites. As previously observed (2-3), calcites exhibit non-first-order kinetics. The data were fit using a model that incorporates both diffusion and isotope-exchange reactions (4). The kinetics derived with this model using the optical-calcite heating experiments of (2) and those measured here are indistinguishable. The model predicts that subtle changes (>10°C) in measured calcite clumped-isotope temperatures can occur at burial temperatures between 60-100°C on million-year timescales. Though small, such changes may have an impact on clumped-isotope-based reconstructions of past surface temperatures and thermal histories. The derived kinetics were compared to clumped-isotope measurements of cogenetic calcites and apatites from slowly cooled carbonatite intrusions. Apparent temperatures are 70-140°C for apatites and 120-190°C for calcites. Measured temperatures for calcites match modeled temperatures using reasonable geological cooling rates. Natural apatite samples yield lower apparent temperatures than predicted based on the model. We propose that this difference is the result of annealment of structural damage in apatites (e.g., generated by radiation damage) during experiments. (1) Dennis and Schrag, 2010; (2) Passey and Henkes, 2012; (3) Henkes et al., 2014. (4) Zhang et al., 1995.

  11. Bordetella pertussis naturally occurring isolates with altered lipooligosaccharide structure fail to fully mature human dendritic cells.

    PubMed

    Brummelman, Jolanda; Veerman, Rosanne E; Hamstra, Hendrik Jan; Deuss, Anna J M; Schuijt, Tim J; Sloots, Arjen; Kuipers, Betsy; van Els, Ccile A C M; van der Ley, Peter; Mooi, Frits R; Han, Wanda G H; Pinelli, Elena

    2015-01-01

    Bordetella pertussis is a Gram-negative bacterium and the causative agent of whooping cough. Despite high vaccination coverage, outbreaks are being increasingly reported worldwide. Possible explanations include adaptation of this pathogen, which may interfere with recognition by the innate immune system. Here, we describe innate immune recognition and responses to different B. pertussis clinical isolates. By using HEK-Blue cells transfected with different pattern recognition receptors, we found that 3 out of 19 clinical isolates failed to activate Toll-like receptor 4 (TLR4). These findings were confirmed by using the monocytic MM6 cell line. Although incubation with high concentrations of these 3 strains resulted in significant activation of the MM6 cells, it was found to occur mainly through interaction with TLR2 and not through TLR4. When using live bacteria, these 3 strains also failed to activate TLR4 on HEK-Blue cells, and activation of MM6 cells or human monocyte-derived dendritic cells was significantly lower than activation induced by the other 16 strains. Mass spectrum analysis of the lipid A moieties from these 3 strains indicated an altered structure of this molecule. Gene sequence analysis revealed mutations in genes involved in lipid A synthesis. Findings from this study indicate that B. pertussis isolates that do not activate TLR4 occur naturally and that this phenotype may give this bacterium an advantage in tempering the innate immune response and establishing infection. Knowledge on the strategies used by this pathogen in evading the host immune response is essential for the improvement of current vaccines or for the development of new ones. PMID:25348634

  12. Naturally occurring structural isomers in serum IgA1 o-glycosylation.

    PubMed

    Takahashi, Kazuo; Smith, Archer D; Poulsen, Knud; Kilian, Mogens; Julian, Bruce A; Mestecky, Jiri; Novak, Jan; Renfrow, Matthew B

    2012-02-01

    IgA is the most abundantly produced antibody and plays an important role in the mucosal immune system. Human IgA is represented by two isotypes, IgA1 and IgA2. The major structural difference between these two subclasses is the presence of nine potential sites of O-glycosylation in the hinge region between the first and second constant region domains of the heavy chain. Thr(225), Thr(228), Ser(230), Ser(232) and Thr(236) have been identified as the predominant sites of O-glycan attachment. The range and distribution of O-glycan chains at each site within the context of adjacent sites in this clustered region create a complex heterogeneity of surface epitopes that is incompletely defined. We previously described the analysis of IgA1 O-glycan heterogeneity by use of high resolution LC-MS and electron capture dissociation tandem MS to unambiguously localize all amino acid attachment sites in IgA1 (Ale) myeloma protein. Here, we report the identification and elucidation of IgA1 O-glycopeptide structural isomers that occur based on amino acid position of the attached glycans (positional isomers) and the structure of the O-glycan chains at individual sites (glycan isomers). These isomers are present in a model IgA1 (Mce1) myeloma protein and occur naturally in normal human serum IgA1. Variable O-glycan chains attached to Ser(230), Thr(233) or Thr(236) produce the predominant positional isomers, including O-glycans composed of a single GalNAc residue. These findings represent the first definitive identification of structural isomeric IgA1 O-glycoforms, define the single-site heterogeneity for all O-glycan sites in a single sample, and have implications for defining epitopes based on clustered O-glycan variability. PMID:22067045

  13. Effect of calcitonin pretreatment on naturally occurring intervertebral disc degeneration in guinea pig

    PubMed Central

    Jiang, Xiaohua; Tian, Faming; Wang, Wenya; Yan, Jinyin; Liu, Huanjiang; Liu, Binbin; Song, Huiping; Zhang, Yingze; Shen, Yong; Zhang, Liu

    2015-01-01

    Introduction: Our previous study suggested protective effects of calcitonin (CT) on experimental osteoarthritis. The aim of the present study was to provide evidence of whether CT pretreatment could prevent naturally occurring intervertebral disc degeneration in guinea pigs. Methods: Forty-two 3 months old female guinea pigs were randomly assigned into 2 groups as follows: Twenty-four were treated by normal saline as control group and sacrificed at 3, 6, 9 and 12 months of age (6 animals at each time point), the other 18 were received salmon CT (8 ug/kg/day, everyday) treatment at 3 months of age and sacrificed at the age of 6, 9 and 12 months respectively. Van Gieson stain and the histological score were used to identify the histological changes of the lumbar intervertebral discs. The disc height and vertebral body height were measured. Immunohistochemistry measurements for glycosaminoglycan, type II collagen, and matrix metalloprotease (MMP)-1 expressions were performed. Bone quality and microstructural changes in the L3-6 lumbar vertebral bodies were assessed by bone mineral density (BMD), micro-CT analysis and biomechanical testing. Results: Histological analysis indicated significantly higher disc degeneration scores in 9-month-old guinea pigs in comparison with younger animals, and grew higher with increasing age. CT treatment significantly reduced the histological score, and increased the disc height and the ratio to vertebral body height in 12 months old animals, as well as upregulated the glycosaminoglycan, type II collagen and inhibited the MMP-1 expression. Micro-CT analysis showed decreased percent bone volume (BV/TV) and increased trabecular separation (Tb.Sp), structural model index (SMI) in 12 months old animals in comparison with the younger animals. Markedly increased BV/TV and decreased Tb.Sp were observed in CT treated animals when compared with control animals. The biomechanical properties including maximum load, maximum stress, yield stress and elastic modulus increased from 3 to 6 months old and thereafter maintained in a stable level, which were enhanced by CT treatment. Conclusion: Pretreatment with CT could prevent naturally occurring intervertebral disc degeneration in guinea pigs, which might be related to the modulation of extracellular matrix metabolism and the integrity and biomechanical properties in adjacent vertebral body. PMID:26379827

  14. Effects of naturally occurring coumarins on hepatic drug-metabolizing enzymes inmice

    SciTech Connect

    Kleiner, Heather E. Xia, Xiaojun; Sonoda, Junichiro; Zhang, Jun; Pontius, Elizabeth; Abey, Jane; Evans, Ronald M.; Moore, David D.; DiGiovanni, John

    2008-10-15

    Cytochromes P450 (P450s) and glutathione S-transferases (GSTs) constitute two important enzyme families involved in carcinogen metabolism. Generally, P450s play activation or detoxifying roles while GSTs act primarily as detoxifying enzymes. We previously demonstrated that oral administration of the linear furanocoumarins, isopimpinellin and imperatorin, modulated P450 and GST activities in various tissues of mice. The purpose of the present study was to compare a broader range of naturally occurring coumarins (simple coumarins, and furanocoumarins of the linear and angular type) for their abilities to modulate hepatic drug-metabolizing enzymes when administered orally to mice. We now report that all of the different coumarins tested (coumarin, limettin, auraptene, angelicin, bergamottin, imperatorin and isopimpinellin) induced hepatic GST activities, whereas the linear furanocoumarins possessed the greatest abilities to induce hepatic P450 activities, in particular P450 2B and 3A. In both cases, this corresponded to an increase in protein expression of the enzymes. Induction of P4502B10, 3A11, and 2C9 by xenobiotics often is a result of activation of the pregnane X receptor (PXR) and/or constitutive androstane receptor (CAR). Using a pregnane X receptor reporter system, our results demonstrated that isopimpinellin activated both PXR and its human ortholog SXR by recruiting coactivator SRC-1 in transfected cells. In CAR transfection assays, isopimpinellin counteracted the inhibitory effect of androstanol on full-length mCAR, a Gal4-mCAR ligand-binding domain fusion, and restored coactivator binding. Orally administered isopimpinellin induced hepatic mRNA expression of Cyp2b10, Cyp3a11, and GSTa in CAR(+/+) wild-type mice. In contrast, the induction of Cyp2b10 mRNA by isopimpinellin was attenuated in the CAR(-/-) mice, suggesting that isopimpinellin induces Cyp2b10 via the CAR receptor. Overall, the current data indicate that naturally occurring coumarins have diverse activities in terms of inducing various xenobiotic metabolizing enzymes based on their chemical structure.

  15. Molecular characterization of a naturally occurring intraspecific recombinant begomovirus with close relatives widespread in southern Arabia

    PubMed Central

    2014-01-01

    Background Tomato leaf curl Sudan virus (ToLCSDV) is a single-stranded DNA begomovirus of tomato that causes downward leaf curl, yellowing, and stunting. Leaf curl disease results in significant yield reduction in tomato crops in the Nile Basin. ToLCSDV symptoms resemble those caused by Tomato yellow leaf curl virus, a distinct and widespread begomovirus originating in the Middle East. In this study, tomato samples exhibiting leaf curl symptoms were collected from Gezira, Sudan. The associated viral genome was molecularly characterized, analyzed phylogenetically, and an infectious clone for one isolate was constructed. Findings The complete genomes for five newly discovered variants of ToLCSDV, ranging in size from 2765 to 2767-bp, were cloned and sequenced, and subjected to pairwise and phylogenetic analyses. Pairwise analysis indicated that the five Gezira isolates shared 97-100% nucleotide identity with each other. Further, these variants of ToLCSDV shared their highest nucleotide identity at 96-98%, 91-95%, 91-92%, and 91-92% with the Shambat, Gezira, Oman and Yemen strains of ToLCSDV, respectively. Based on the high maximum nucleotide identities shared between these ToLCSDV variants from Gezira and other previously recognized members of this taxonomic group, they are considered isolates of the Shambat strain of ToLCSDV. Analysis of the complete genome sequence for these new variants revealed that they were naturally occurring recombinants between two previously reported strains of ToLCSDV. Finally, a dimeric clone constructed from one representative ToLCSV genome from Gezira was shown to be infectious following inoculation to tomato and N. benthamiana plants. Conclusion Five new, naturally occurring recombinant begomovirus variants (>96% shared nt identity) were identified in tomato plants from Gezira in Sudan, and shown to be isolates of the Shambat strain of ToLCSDV. The cloned viral genome was infectious in N. benthamiana and tomato plants, and symptoms in tomato closely resembled those observed in field infected tomato plants, indicating the virus is the causal agent of the leaf curl disease. The symptoms that developed in tomato seedlings closely resembled those observed in field infected tomato plants, indicating that ToLCSDV is the causal agent of the leaf curl disease in Gezira. PMID:24890736

  16. ISOTOPIC EVIDENCE FOR NATURALLY OCCURRING SULFATE PONDS IN THE KANKAKEE RIVER BASIN, ILLINOIS-INDIANA

    EPA Science Inventory

    Design of constructed wetlands in the Kankakee watershed, Indiana, include pumping and distribution ditches leaving former channelized river levees intact. Resultant changes in shallow ground water - surface water interactions may be contributing elevated sulfate to wetland ponds...

  17. Long-term toxicity of naturally occurring asbestos in male Fischer 344 rats.

    PubMed

    Cyphert, Jaime M; McGee, Marie A; Nyska, Abraham; Schladweiler, Mette C; Kodavanti, Urmila P; Gavett, Stephen H

    2016-01-01

    Naturally occurring asbestos (NOA) fibers are found in geologic deposits that may be disturbed by mining, earthworks, or natural processes, resulting in adverse health risks to exposed individuals. The toxicities of Libby amphibole and NOA samples including Sumas Mountain chrysotile (SM), El Dorado tremolite (ED), and Ontario ferroactinolite cleavage fragments (ON) were compared in male Fischer 344 (F344) rats 15 mo after exposure. Rat-respirable fractions of LA and SM displayed greater mean lengths and aspect ratios than ED and ON. After a single intratracheal (IT) instillation (0.5 or 1.5 mg/rat), persistent changes in ventilatory parameters and a significant increase in lung resistance at baseline and after methacholine aerosol dosing were found only in rats exposed to 1.5 mg SM. High-dose ED significantly elevated bronchoalveolar lavage lactate dehydrogenase (LDH) activity and protein levels, while high-dose SM increased ?-glutamyl transferase and LDH activities. A moderate degree of lung interstitial fibrosis after exposure to 1.5 mg SM persisted 15 mo after exposure, unchanged from previous findings at 3 mo. LA induced mild fibrosis, while ED and ON produced minimal and no apparent fibrosis, respectively. Bronchioloalveolar carcinoma was observed 15 mo after exposure to LA or ED. Data demonstrated that SM, given by bolus IT dosing on an equivalent mass basis, induced greater pulmonary function deficits, airway hyperresponsiveness, and interstitial fibrosis than other NOA, although unlike LA and ED, no apparent evidence for carcinogenicity was found. All NOA samples except ON cleavage fragments produced some degree of long-term toxicity. PMID:26818398

  18. Infrared spectroscopic examination of the interaction of urea with the naturally occurring zeolite clinoptilolite

    USGS Publications Warehouse

    Byler, D.M.; Gerasimowicz, W.V.; Stockette, V.M.; Eberl, D.D.

    1991-01-01

    Infrared spectroscopy has shown for the first time that the naturally occurring zeolite clinoptilolite can absorb urea, (NH2)2CO, under ambient conditions from either aqueous or ethanolic solutions. The two strongest NH stretching bands at 3441 and 3344 cm-1 in pure, solid urea shift to higher frequency (about 3504 and 3401 cm-1) after absorption. Two of the four urea bands in the 1800-1300 cm-1 range (at 1683 and 1467 cm-1) undergo marked downward shifts to about 1670 and 1445 cm-1. The other two bands show little change in frequency. The strong band at 1602 cm-1, however, diminishes in intensity to little more than an ill-defined shoulder on the 1626-cm-1 peak. When clinoptilolite is heated to 450 ??C and then treated with molten urea (ca. 140 ??C) for several minutes, and finally washed twice with ethanol to remove excess unreacted urea, further changes become apparent in the spectrum of the urea-treated clinoptilolite. The two NH stretching bands broaden without significant change in frequency. Two new bands appear in the midfrequency range at 1777 (weak) and 1719 (medium strong) cm-1. Of the four original midfrequency peaks, the one at 1602 cm-1 is now absent. Two others (1627 and 1440 cm-1) exhibit little change, while the fourth has broadened and shifted down to 1663 cm-1, where it appears as a shoulder on the band at 1627 cm-1. Both treatments clearly induce interaction between urea and the zeolite which seems to result in significant modifications in the nature of the hydrogen bonding of the substrate. ?? 1991.

  19. Potential environmental and regulatory implications of naturally occurring radioactive materials (NORM).

    PubMed

    Paschoa, A S

    1998-03-01

    The immense volume of naturally occurring radioactive materials (NORM) wastes produced annually by extracting industries throughout the world deserves to come to the attention of international and national environmental protection agencies and regulatory bodies. Although a great deal of work has been done in the fields of radiation protection and remedial actions concerning uranium and other mines, the need to dispose of diffuse NORM wastes will have environmental and regulatory implications that thus far are not fully appreciated. NORM wastes constitute, by and large, unwanted byproducts of industrial activities as diverse as thorium and uranium milling, niobium, tin and gold mining extraction, water treatment, and the production of oil, gas, phosphate fertilizer, coal fire and aluminum. The volumes of NORM wastes produced annually could reach levels so high that the existing low level radioactive waste (LLRW) facilities would be readily occupied by NORM if controlled disposal procedures were not adopted. On the other hand, NORM cannot just be ignored as being below radiological concern (BRC) or lower than exempt concentration levels (ECLs), because sometimes NORM concentrations reach levels as high as 1 x 10(3) kBq/kg for 226Ra, and not much less for 228Ra. Unfortunately, thus far there is not enough information available concerning NORM wastes in key industries, though the international scientific community has been concerned, for a long time now, with technologically enhanced natural radiation exposures (TENRE). This article is written with the intention of examining, to the extent possible, the potential environmental and regulatory implications of NORM wastes being produced in selected industries. PMID:9451772

  20. Heavy metal complexation with naturally occurring organic ligands in wetland ecosystems

    SciTech Connect

    Tuschall, J.R. Jr.

    1981-01-01

    The mode, rate, and extent of heavy metal uptake by freshwater wetlands were investigated as well as heavy metal complexation by a variety of soluble organics. One study involved adding Cd, Cu, Mn, and Zn to septage from Waldo, Florida, and pumping the wastewater through a 10 x 40-m corridor in a cypress swamp. Soluble concentrations of all four metals decreased within the corridor to levels close to those considered acceptable for discharge to surface water. Rates of immobilization were calculated to be a minimum of 7.2, 36, and 72, and 72 g metal/ha.day/sup -1/ for Cd, Cu, Mn, and Zn, respectively. In addition, microcosms (model ecosystems that simulated a swamp) were constructed for a laboratory investigation of factors that control metal immobilization rates. Of the factors - dissolved organic carbon, iron, calcium, sulfide, and pH - the latter two most greatly affected metal immobilization rates. Heavy metal interactions with naturally occurring organics and model compounds were examined by complexometric titrations using five separate techniques. Three of the techniques used (anodic stripping voltammetry (ASV) ion-selective electrode, and fluorescence quenching) were previously published methods, and the other two methods (continuous flow ultrafiltration and competing ligand/differential spectroscopy) were developed for this study. Each procedure was used to determine the available metal binding ability of the organic solutions and the conditional stability constants of the metal-organic complexes. For each solution, agreement among the procedures was good except for the ASV method, which produced results lower than the others. Additionally, the ASV method yielded a conditional stability constant for copper with ethylenedinitrilotetraacetic acid that was five orders of magnitude lower than other published values. The low ASV results for copper with swamp-water organics were found to be caused by the reducible nature of organically complexed copper.

  1. Natural thorium isotopes in marine sediment core off Labuan port

    SciTech Connect

    Hafidz, B. Y.; Asnor, A. S.; Terence, R. C.; Mohamed, C. A. R.

    2014-02-12

    Sediment core was collected from Labuan port and analyzed to determine the radioactivity of thorium (Th) isotopes. The objectives of this study are to determine the possible sources of Th isotopes at Labuan port and estimates the sedimentation rate based on {sup 228}Th/{sup 232}Th model. The results suggest the {sup 230}Th and {sup 232}Th might be originated from terrestrial sedimentary rock while {sup 228}Th originated by authigenic origin. High ratio value of {sup 230}Th/{sup 232}Th detected at the top surface sediment indicates the increasing of {sup 230}Th at the recent years which might be contributed from the anthropogenic sources. The sedimentation rate of core sediment from Labuan Port was successfully estimated by using {sup 228}Th/{sup 232}Th model. The result show high sedimentation rate with 4.67 cm/year indicates rapid deposition occurred at this study area due to the high physical activity at the Labuan port. By assume the constant sedimentation rate at this area; we estimated the age of 142 cm core sediment obtained from Labuan port is 32 years started from 1981 to 2012. This chronology will be used in forthcoming research to investigate the historical profile of anthropogenic activities affecting the Labuan port.

  2. Natural thorium isotopes in marine sediment core off Labuan port

    NASA Astrophysics Data System (ADS)

    Hafidz, B. Y.; Asnor, A. S.; Terence, R. C.; Mohamed, C. A. R.

    2014-02-01

    Sediment core was collected from Labuan port and analyzed to determine the radioactivity of thorium (Th) isotopes. The objectives of this study are to determine the possible sources of Th isotopes at Labuan port and estimates the sedimentation rate based on 228Th/232Th model. The results suggest the 230Th and 232Th might be originated from terrestrial sedimentary rock while 228Th originated by authigenic origin. High ratio value of 230Th/232Th detected at the top surface sediment indicates the increasing of 230Th at the recent years which might be contributed from the anthropogenic sources. The sedimentation rate of core sediment from Labuan Port was successfully estimated by using 228Th/232Th model. The result show high sedimentation rate with 4.67 cm/year indicates rapid deposition occurred at this study area due to the high physical activity at the Labuan port. By assume the constant sedimentation rate at this area; we estimated the age of 142 cm core sediment obtained from Labuan port is 32 years started from 1981 to 2012. This chronology will be used in forthcoming research to investigate the historical profile of anthropogenic activities affecting the Labuan port.

  3. Evaluation of occupational exposure to naturally occurring radioactive materials in the Iranian ceramics industry.

    PubMed

    Fathabadi, N; Farahani, M V; Amani, S; Moradi, M; Haddadi, B

    2011-06-01

    Zircon contains small amounts of uranium, thorium and radium in its crystalline structure. The ceramic industry is one of the major consumers of zirconium compounds that are used as an ingredient at ?10-20 % by weight in glaze. In this study, seven different ceramic factories have been investigated regarding the presence of radioactive elements with focus on natural radioactivity. The overall objective of this investigation is to provide information regarding the radiation exposure to workers in the ceramic industry due to naturally occurring radioactive materials. This objective is met by collecting existing radiological data specific to glaze production and generating new data from sampling activities. The sampling effort involves the whole process of glaze production. External exposures are monitored using a portable gamma-ray spectrometer and environmental thermoluminescence dosimeters, by placing them for 6 months in some workplaces. Internal routes of exposure (mainly inhalation) are studied using air sampling, and gross alpha and beta counting. Measurement of radon gas and its progeny is performed by continuous radon gas monitors that use pulse ionisation chambers. Natural radioactivity due to the presence of ?U, Th and ??K in zirconium compounds, glazes and other samples is measured by a gamma-ray spectrometry system with a high-purity germanium detector. The average concentrations of ?U and Th observed in the zirconium compounds are >3300 and >550 Bq kg?, respectively. The specific activities of other samples are much lower than in zirconium compounds. The annual effective dose from external radiation had a mean value of ?0.13 mSv y?. Dust sampling revealed the greatest values in the process at the powdering site and hand weighing places. In these plants, the annual average effective dose from inhalation of long-lived airborne radionuclides was 0.226 mSv. Rn gas concentrations in the glaze production plant and storage warehouse were found to range from 10 to 213 Bq m?. In this study, the estimated annual effective doses to exposed workers were <1 mSv y?. PMID:21148590

  4. Pennsylvania's technologically enhanced, naturally occurring radioactive material experiences and studies of the oil and gas industry.

    PubMed

    Allard, David J

    2015-02-01

    This presentation provides an overview of the Commonwealth of Pennsylvania's experiences and ongoing studies related to technologically enhanced, naturally occurring radioactive material (TENORM) in the oil and gas industry. It has been known for many years that Pennsylvania's geology is unique, with several areas having relatively high levels of natural uranium and thorium. In the 1950s, a few areas of the state were evaluated for commercial uranium production. In the late 1970s, scoping studies of radon in homes prompted the Pennsylvania Department of Environmental Protection (DEP) Bureau of Radiation Protection (BRP) to begin planning for a larger state-wide radon study. The BRP and Oil and Gas Bureau also performed a TENORM study of produced water in the early 1990s for a number of conventional oil and gas wells. More recently, BRP and the Bureau of Solid Waste developed radiation monitoring regulations for all Pennsylvania solid waste disposal facilities. These were implemented in 2001, prompting another evaluation of oil and gas operations and sludge generated from the treatment of conventionally produced water and brine but mainly focused on the disposal of TENORM solid waste in the state's Resource Conservation and Recovery Act Subtitle D landfills. However, since 2008, the increase in volumes of gas well wastewater and levels of Ra observed in the unconventional shale gas well flow-back fracking water has compelled DEP to fully re-examine these oil and gas operations. Specifically, with BRP in the lead, a new TENORM study of oil and gas operations and related wastewater treatment operations has been initiated (), supported by an American National Standards Institute standard on TENORM () and a U.S. Government Accountability Office report on shale resource development and risks (). This study began in early 2013 and will examine the potential public and worker radiation exposure and environmental impact as well as re-evaluate TENORM waste disposal. This presentation summarizes conventional and unconventional oil and gas well operations, geology and respective uranium/thorium content, radium content in oil and gas wastewater, treatment solids, radon in natural gas, the scope of other TENORM issues in the state, regulatory framework, national regulations and guidance. It also provides an overview of past and the status of ongoing TENORM studies in the Commonwealth (; Rowan and Kraemer 2012; ). PMID:25551500

  5. A molecular informed poroelastic model for organic-rich, naturally occurring porous geocomposites

    NASA Astrophysics Data System (ADS)

    Monfared, Siavash; Ulm, Franz-Josef

    2016-03-01

    Molecular simulation results on organic maturity (mature and immature kerogen as the two asymptotic cases) are introduced into a continuum micromechanics based model for organic-rich shales. Through a fundamental functional relationship that constrains microporous kerogen density and elasticity variable spaces and within the framework of effective media theory; the model bridges the gap between asymptotic cases of organic maturity with texture as the overriding theme, specifically a matrix/inclusion (Mori-Tanaka) texture for immature systems and a granular (self-consistent) texture for mature ones. The utility of the molecular results merged into a continuum framework is demonstrated by estimating kerogen's microporosity (< 2 nm) from nanoindentation measurements. The effect of burial and diagenetic processes on the effective poroelasticity of these porous, naturally occurring geocomposites are captured by introduction of imperfect interfaces. Finally, the performance of the model is fully characterized by ranking the normalized contribution of uncertainty of input to the overall behavior and parameters of interest to geophysicists and geomechanicians such as degree of anisotropy and in situ stresses.

  6. What should a radiation regulator do about naturally occurring radioactive material?

    PubMed

    Loy, J

    2015-06-01

    The standard regulatory framework of authorisation, review and assessment, inspection and enforcement, and regulation making is directed principally towards ensuring the regulatory control of planned exposure situations. Some mining and industrial activities involving exposures to naturally occurring radioactive material (NORM), such as uranium mining or the treatment and conditioning of NORM residues, may fit readily within this standard framework. In other cases, such as oil and gas exploration and production, the standard regulatory framework needs to be adjusted. For example, it is not sensible to require that an oil company seek a licence from the radiation regulator before drilling a well. The paper discusses other approaches that a regulator might take to assure protection and safety in such activities involving exposures to NORM, including the use of conditional exemptions from regulatory controls. It also suggests some areas where further guidance from the International Commission on Radiological Protection on application of the system of radiological protection to NORM would assist both regulators and operators. PMID:25816273

  7. Larvicidal activity of naturally occurring naphthalenedione and its structurally related analogs against three mosquito species.

    PubMed

    Jeon, Ju-Hyun; Kim, Min-Gi; Lee, Hoi-Seon

    2015-03-01

    The objective of this study was to determine the larvicidal activity of an active compound isolated from Cercis chinensis heartwood and its structurally related analogs against 4th-stage Aedes aegypti, Culex pipiens pallens, and Ae. togoi. The larvicidal compound of C. chinensis was isolated with the use of various chromatographic techniques and identified as analogs of 1,4-naphthalenedione. Based on the median lethal concentration (LC(50)) values of commercially procured analogs against Ae. aegypti larvae, the most toxic analog was 2-bromo-1,4-naphthalenedione (1.19 g/ml); followed by 5-hydroxy-1,4-naphthalenedione (1.72 g/ml); 2-methyl-1,4-naphthalenedione (9.12 g/ml); 2-hydroxy-1,4-naphthalenedione (10.76 g/ml); and 2-methoxy-1,4-naphthalenedione (12.50 g/ml). Similar results were observed against Cx. p. pallens and Ae. togoi larvae with 1,4-naphthalenedione analogs. These results also showed that 1,4-naphthalenedione analogs were less toxic than the organophosphate pirimiphos-methyl. Nonetheless, naturally occurring C. chinensis-derived materials and 1,4-naphthalenedione analogs have potential for development as mosquito larvicidal agents. PMID:25843178

  8. Effect of Naturally Occurring Ozone Air Pollution Episodes on Pulmonary Oxidative Stress and Inflammation

    PubMed Central

    Pirozzi, Cheryl; Sturrock, Anne; Weng, Hsin-Yi; Greene, Tom; Scholand, Mary Beth; Kanner, Richard; Paine, Robert

    2015-01-01

    This study aimed to determine if naturally occurring episodes of ozone air pollution in the Salt Lake Valley in Utah, USA, during the summer are associated with increased pulmonary inflammation and oxidative stress, increased respiratory symptoms, and decreased lung function in individuals with chronic obstructive pulmonary disease (COPD) compared to controls. We measured biomarkers (nitrite/nitrate (NOx), 8-isoprostane) in exhaled breath condensate (EBC), spirometry, and respiratory symptoms in 11 former smokers with moderate-to-severe COPD and nine former smokers without airflow obstruction during periods of low and high ozone air pollution. High ozone levels were associated with increased NOx in EBC in both COPD (8.7 (8.5) vs. 28.6 (17.6) ?mol/L on clean air vs. pollution days, respectively, p < 0.01) and control participants (7.6 (16.5) vs. 28.5 (15.6) ?mol/L on clean air vs. pollution days, respectively, p = 0.02). There was no difference in pollution effect between COPD and control groups, and no difference in EBC 8-isoprostane, pulmonary function, or respiratory symptoms between clean air and pollution days in either group. Former smokers both with and without airflow obstruction developed airway oxidative stress and inflammation in association with ozone air pollution episodes. PMID:25985308

  9. Effect of naturally occurring ozone air pollution episodes on pulmonary oxidative stress and inflammation.

    PubMed

    Pirozzi, Cheryl; Sturrock, Anne; Weng, Hsin-Yi; Greene, Tom; Scholand, Mary Beth; Kanner, Richard; Paine, Robert

    2015-05-01

    This study aimed to determine if naturally occurring episodes of ozone air pollution in the Salt Lake Valley in Utah, USA, during the summer are associated with increased pulmonary inflammation and oxidative stress, increased respiratory symptoms, and decreased lung function in individuals with chronic obstructive pulmonary disease (COPD) compared to controls. We measured biomarkers (nitrite/nitrate (NOx), 8-isoprostane) in exhaled breath condensate (EBC), spirometry, and respiratory symptoms in 11 former smokers with moderate-to-severe COPD and nine former smokers without airflow obstruction during periods of low and high ozone air pollution. High ozone levels were associated with increased NOx in EBC in both COPD (8.7 (8.5) vs. 28.6 (17.6) ?mol/L on clean air vs. pollution days, respectively, p < 0.01) and control participants (7.6 (16.5) vs. 28.5 (15.6) ?mol/L on clean air vs. pollution days, respectively, p = 0.02). There was no difference in pollution effect between COPD and control groups, and no difference in EBC 8-isoprostane, pulmonary function, or respiratory symptoms between clean air and pollution days in either group. Former smokers both with and without airflow obstruction developed airway oxidative stress and inflammation in association with ozone air pollution episodes. PMID:25985308

  10. Radiological dose assessment related to management of naturally occurring radioactive materials generated by the petroleum industry

    SciTech Connect

    Smith, K.P.; Blunt, D.L.; Williams, G.P.; Tebes, C.L.

    1996-09-01

    A preliminary radiological dose assessment of equipment decontamination, subsurface disposal, landspreading, equipment smelting, and equipment burial was conducted to address concerns regarding the presence of naturally occurring radioactive materials (NORM) in production waste streams. The assessment estimated maximum individual dose equivalents for workers and the general public. Sensitivity analyses of certain input parameters also were conducted. On the basis of this assessment, it is concluded that (1) regulations requiring workers to wear respiratory protection during equipment cleaning operations are likely to result in lower worker doses, (2) underground injection and downhole encapsulation of NORM wastes present a negligible risk to the general public, and (3) potential doses to workers and the general public related to smelting NORM-contaminated equipment can be controlled by limiting the contamination level of the initial feed. It is recommended that (1) NORM wastes be further characterized to improve studies of potential radiological doses; (2) states be encouraged to permit subsurface disposal of NORM more readily, provided further assessments support this study; results; (3) further assessment of landspreading NORM wastes be conducted; and (4) the political, economic, sociological, and nonradiological issues related to smelting NORM-contaminated equipment be studied to fully examine the feasibility of this disposal option.

  11. Characterizing Older Adults' Involvement in Naturally Occurring Retirement Community (NORC) Supportive Service Programs.

    PubMed

    Greenfield, Emily A; Fedor, James P

    2015-01-01

    Naturally Occurring Retirement Community (NORC) Supportive Service Programs constitute one of the longest-standing models for age-friendly community initiatives. As a support-focused model, NORC programs typically offer a range of benefits--including direct services, group activities, and broader community development activities--that are intended to engage older adults with diverse needs, preferences, and interests. Moreover, NORC programs are designed to be used according to the needs of the particular participant engaging with them at a particular point in time. This range and flexibility of benefits indicate the importance of more systematically characterizing the ways in which older adults are involved with NORC programs. For this purpose, we used data from in-depth interviews with 35 residents across 6 NORC programs in New York City. Qualitative analysis revealed 6 ordered categories of involvement: (a) consciously no involvement; (b) involved, but not consciously; (c) relationship with staff only; (d) selectively involved with a strong sense of security; (e) NORC program leaders; and (f) dependence on the NORC program. Overall, results indicate how older adults' involvement in NORC programs can be characterized beyond their utilization of specific types of services and by their relationship with the program as a whole. Findings suggest the importance for outcomes research on NORC programs and related models to consider subgroup differences by involvement. Results also provide directions for theory development on engagement in voluntary programs, as well as for practice to enhance older adults' involvement in supportive service programs. PMID:25734969

  12. Naturally occurring HCA1 missense mutations result in loss of function: potential impact on lipid deposition

    PubMed Central

    Doyle, Jamie R.; Lane, Jacqueline M.; Beinborn, Martin; Kopin, Alan S.

    2013-01-01

    The hydroxy-carboxylic acid receptor (HCA1) is a G protein-coupled receptor that is highly expressed on adipocytes and considered a potential target for the treatment of dyslipidemia. In the current study, we investigated the pharmacological properties of naturally occurring variants in this receptor (H43Q, A110V, S172L, and D253H). After transient expression of these receptors into human embryonic kidney 293 cells, basal and ligand-induced signaling were assessed using luciferase reporter gene assays. The A110V, S172L, and D253 variants showed reduced basal activity; the S172L mutant displayed a decrease in potency to the endogenous ligand l-lactate. Both the S172L and D253H variants also showed impaired cell surface expression, which may in part explain the reduced activity of these receptors. The impact of a loss in HCA1 function on lipid accumulation was investigated in the adipocyte cell line, OP9. In these cells, endogenous HCA1 transcript levels rapidly increased and reached maximal levels 3 days after the addition of differentiation media. Knockdown of HCA1 using siRNA resulted in an increase in lipid accumulation as assessed by quantification of Nile Red staining and TLC analysis. Our data suggest that lipid homeostasis may be altered in carriers of selected HCA1 missense variants. PMID:23268337

  13. Method for Collecting Naturally Occurring Airborne Bacterial Spores for Determining Their Thermal Resistance

    PubMed Central

    Puleo, J. R.; Favero, M. S.; Oxborrow, G. S.; Herring, C. M.

    1975-01-01

    The ability to determine the thermal resistance of naturally occurring air borne bacterial spores associated with spacecraft and their assembly areas has been hindered by lack of an effective collecting system. Efforts to collect and concentrate spores with air samplers or from air filters have not been successful. A fallout method was developed for this purpose and tested. Sterile Teflon ribbons (7.6 by 183 cm) were exposed in pertinent spacecraft assembly areas and subsequently treated with dry heat. Thermal inactivation experiments were conducted at 125 and 113 C. Heating intervals ranged from 1 to 12 h at 125 C and 6, 12, 18, and 24 h at 113 C. Eight hours was the longest heating time yielding survivors at 125 C, whereas survivors were recovered at all of the heating intervals at 113 C. D125C values were calculated using the fractional-replicate-unit-negative technique of Pflug and Schmidt (1968) and ranged from 25 to 126 min. This variation indicated that the most probable number of survivors at each heating interval did not fall on a straight line passing through the initial spore population. However, the most-probable-number values taken alone formed a straight line suggesting logarithmic thermal destruction of a subpopulation of spores with a D125C value of 6.3 h. PMID:1106321

  14. Actinonin, a naturally occurring antibacterial agent, is a potent deformylase inhibitor.

    PubMed

    Chen, D Z; Patel, D V; Hackbarth, C J; Wang, W; Dreyer, G; Young, D C; Margolis, P S; Wu, C; Ni, Z J; Trias, J; White, R J; Yuan, Z

    2000-02-15

    Peptide deformylase (PDF) is essential in prokaryotes and absent in mammalian cells, thus making it an attractive target for the discovery of novel antibiotics. We have identified actinonin, a naturally occurring antibacterial agent, as a potent PDF inhibitor. The dissociation constant for this compound was 0.3 x 10(-)(9) M against Ni-PDF from Escherichia coli; the PDF from Staphylococcus aureus gave a similar value. Microbiological evaluation revealed that actinonin is a bacteriostatic agent with activity against Gram-positive and fastidious Gram-negative microorganisms. The PDF gene, def, was placed under control of P(BAD) in E. coli tolC, permitting regulation of PDF expression levels in the cell by varying the external arabinose concentration. The susceptibility of this strain to actinonin increases with decreased levels of PDF expression, indicating that actinonin inhibits bacterial growth by targeting this enzyme. Actinonin provides an excellent starting point from which to derive a more potent PDF inhibitor that has a broader spectrum of antibacterial activity. PMID:10684604

  15. Naturally-occurring TGR5 agonists modulating glucagon-like peptide-1 biosynthesis and secretion.

    PubMed

    Jafri, Laila; Saleem, Samreen; Calderwood, Danielle; Gillespie, Anna; Mirza, Bushra; Green, Brian D

    2016-04-01

    Selective GLP-1 secretagogues represent a novel potential therapy for type 2 diabetes mellitus. This study examined the GLP-1 secretory activity of the ethnomedicinal plant, Fagonia cretica, which is postulated to possess anti-diabetic activity. After extraction and fractionation extracts and purified compounds were tested for GLP-1 and GIP secretory activity in pGIP/neo STC-1 cells. Intracellular levels of incretin hormones and their gene expression were also determined. Crude F. cretica extracts stimulated both GLP-1 and GIP secretion, increased cellular hormone content, and upregulated gene expression of proglucagon, GIP and prohormone convertase. However, ethyl acetate partitioning significantly enriched GLP-1 secretory activity and this fraction underwent bioactivity-guided fractionation. Three isolated compounds were potent and selective GLP-1 secretagogues: quinovic acid (QA) and two QA derivatives, QA-3β-O-β-d-glycopyranoside and QA-3β-O-β-d-glucopyranosyl-(28→1)-β-d-glucopyranosyl ester. All QA compounds activated the TGR5 receptor and increased intracellular incretin levels and gene expression. QA derivatives were more potent GLP-1 secretagogues than QA. This is the first time that QA and its naturally-occurring derivatives have been shown to activate TGR5 and stimulate GLP-1 secretion. These data provide a plausible mechanism for the ethnomedicinal use of F. cretica and may assist in the ongoing development of selective GLP-1 agonists. PMID:26820940

  16. Naturally occurring cancers in dogs: insights for translational genetics and medicine.

    PubMed

    Alvarez, Carlos E

    2014-01-01

    Here, we briefly review the state of knowledge of human cancer genetics to elaborate on the need for different types of mammalian models, highlighting the strengths of the dog. Mouse models are unparalleled for their experimental tractability and rapid genetic manipulation but have some key limitations in the area of human relevance. Companion dog models are attractive, because they are genetically more similar to humans, share environmental exposures with their owners, suffer from the same diseases as humans, and receive a high level of health care. They are ideal for the study of chronic diseases, because they age five to eight times faster than humans and generally live to old age. In addition, each dog breed is on the order of 100-fold genetically simpler than the whole human or dog population. These traits make the dog ideal for the study of complex genetics of naturally occurring cancers. Here, we contrast the relative strengths of cancer genetics in humans and dogs. We propose that humans are most ideal for the study of somatic cancer genetics, whereas dogs are most ideal for germline genetics. That proposition is supported by comparison of genome-wide association studies (GWASs) in human and canine cancer. One of the advantages of dog cancer GWASs is the ability to rapidly map complex traits, conduct fine mapping and identification of causative variation, and thus be in a position to move on to functional studies. We mention how these strengths of dog models will lead to rapid advances in translational medicine. PMID:24936028

  17. Aluminum-chloride-phthalocyanine encapsulated in liposomes: activity against naturally occurring dog breast cancer cells.

    PubMed

    Rocha, Martha S T; Lucci, Carolina M; Longo, Joo Paulo F; Galera, Paula D; Simioni, Andreza R; Lacava, Zulmira G M; Tedesco, Antnio C; Azevedo, Ricardo B

    2012-04-01

    Breast tumors represent the most common malignant tumors. Current treatments for humans and pets rely on tumor excision and adjuvant chemotherapy, which may affect both cancer cells and normal cells. Photodynamic therapy (PDT) is an approved treatment modality for a variety of cancers and was recently recommended as a first-line treatment for non-melanoma skin cancers for humans. The main purpose of the present study was to determine the efficacy of PDT using aluminum-chloride-phthalocyanine that is encapsulated in liposomes and LED as a light source to kill naturally occurring female dog breast cancer in vitro. The cytotoxicity behavior of the encapsulated photosensitizer in the dark and under irradiation using the 670 nm laser were investigated using classical trypan blue and MTT cell viability tests, acridine orange and ethidium bromide staining to label organelles, and cell morphology. Cell morphology was evaluated using light and electron microscopy. Our results demonstrate a reduced cell viability that is associated with morphologic alterations. The neoplasic cell destruction was predominantly mediated via a necrotic process, which was assayed using acridine orange and ethidium bromide staining. These findings were confirmed using light and electronic microscopy. The photosensitizer or laser irradiation alone did not induce cytotoxicity or morphological alterations, indicating the safety and efficacy of PDT with chloro-aluminum-phthalocyanine that was encapsulated in liposomes for the treatment of breast cancer cells in vitro. PMID:22515076

  18. Masculinised Behaviour of XY Females in a Mammal with Naturally Occuring Sex Reversal.

    PubMed

    Saunders, Paul A; Franco, Thomas; Sottas, Camille; Maurice, Tangui; Ganem, Guila; Veyrunes, Frédéric

    2016-01-01

    Most sex differences in phenotype are controlled by gonadal hormones, but recent work on laboratory strain mice that present discordant chromosomal and gonadal sex showed that sex chromosome complement can have a direct influence on the establishment of sex-specific behaviours, independently from gonads. In this study, we analyse the behaviour of a rodent with naturally occurring sex reversal: the African pygmy mouse Mus minutoides, in which all males are XY, while females are of three types: XX, XX* or X*Y (the asterisk represents an unknown X-linked mutation preventing masculinisation of X*Y embryos). X*Y females show typical female anatomy and, interestingly, have greater breeding performances. We investigate the link between sex chromosome complement, behaviour and reproductive success in females by analysing several behavioural features that could potentially influence their fitness: female attractiveness, aggressiveness and anxiety. Despite sex chromosome complement was not found to impact male mate preferences, it does influence some aspects of both aggressiveness and anxiety: X(*)Y females are more aggressive than the XX and XX*, and show lower anxiogenic response to novelty, like males. We discuss how these behavioural differences might impact the breeding performances of females, and how the sex chromosome complement could shape the differences observed. PMID:26964761

  19. Using naturally occurring polysaccharides to align molecules with nonlinear optical activity

    NASA Technical Reports Server (NTRS)

    Prasthofer, Thomas

    1996-01-01

    The Biophysics and Advanced Materials Branch of the Microgravity Science and Applications Division at Marshall Space Flight Center has been investigating polymers with the potential for nonlinear optical (NLO) applications for a number of years. Some of the potential applications for NLO materials include optical communications, computing, and switching. To this point the branch's research has involved polydiacetylenes, phthalocyanins, and other synthetic polymers which have inherent NLO properties. The aim of the present research is to investigate the possibility of using naturally occurring polymers such as polysaccharides or proteins to trap and align small organic molecules with useful NLO properties. Ordering molecules with NLO properties enhances 3rd order nonlinear effects and is required for 2nd order nonlinear effects. Potential advantages of such a system are the flexibility to use different small molecules with varying chemical and optical properties, the stability and cost of the polymers, and the ability to form thin, optically transparent films. Since the quality of any polymer films depends on optimizing ordering and minimizing defects, this work is particularly well suited for microgravity experiments. Polysaccharide and protein polymers form microscopic crystallites which must align to form ordered arrays. The ordered association of crystallites is disrupted by gravity effects and NASA research on protein crystal growth has demonstrated that low gravity conditions can improve crystal quality.

  20. Characterization of Naturally Occurring Atrazine-Resistant Isolates of the Purple Non-Sulfur Bacteria

    PubMed Central

    Brown, Alfred E.; Luttrell, Robin; Highfill, Claudia T.; Rushing, Ann E.

    1990-01-01

    Six isolates of the purple non-sulfur bacteria, which upon primary isolation were naturally resistant to the herbicide atrazine, were characterized with respect to their taxonomic identity and the mechanism of their resistance. On the basis of electron microscopy, photopigment analysis, and other criteria, they were identified as strains of Rhodopseudomonas acidophila, Rhodopseudomonas palustris, or Rhodocyclus gelatinosus. These isolates exhibited degrees of atrazine resistance which ranged from 1.5 to about 4 times greater than that of cognate reference strains (American Type Culture Collection) tested. Furthermore, all of the reference strains tested were more intrinsically resistant to atrazine than was Rhodobacter sphaeroides. No unique plasmids which might encode for herbicide degradation or inactivation were found in these isolates. Resistance to the herbicide in these isolates was not the result of diminished binding of the herbicide to the L subunit of the bacterial reaction center. Differences in herbicide resistance among the various species of this group may be the result of compositional and chemical differences in the individual reaction centers. However, the increase in atrazine resistance for the isolates characterized in this study probably occurs by undefined mechanisms and not necessarily by changes in the binding of the herbicide to the L subunit of the photosynthetic reaction center. Images PMID:16348126

  1. ? arcades: recurring motifs in naturally occurring and disease-related amyloid fibrils

    PubMed Central

    Kajava, Andrey V.; Baxa, Ulrich; Steven, Alasdair C.

    2010-01-01

    Amyloid fibrils are filamentous protein aggregates that accumulate in diseases such as Alzheimers or type II diabetes. The amyloid-forming protein is disease specific. Amyloids may also be formed in vitro from many other proteins, after first denaturing them. Unlike the diverse native folds of these proteins, their amyloids are fundamentally similar in being rigid, smooth-sided, and cross-?-structured, that is, with ? strands running perpendicular to the fibril axis. In the absence of high-resolution fibril structures, increasingly credible models are being derived by integrating data from a crossfire of experimental techniques. Most current models of disease-related amyloids invoke ? arcades, columnar structures produced by in-register stacking of ? arches. A ? arch is a strand-turn-strand motif in which the two ? strands interact via their side chains, not via the polypeptide backbone as in a conventional ? hairpin. Crystal structures of ?-solenoids, a class of proteins with amyloid-like properties, offer insight into the ?-arc turns found in ? arches. General conformational and thermodynamic considerations suggest that complexes of 2 or more ? arches may nucleate amyloid fibrillogenesis in vivo. The apparent prevalence of ? arches and their components have implications for identifying amyloidogenic sequences, elucidating fibril polymorphisms, predicting the locations and conformations of ? arcs within amyloid fibrils, and refining existing fibril models.Kajava, A. V., Baxa, U., Steven, A. C. ? arcades: recurring motifs in naturally occurring and disease-related amyloid fibrils. PMID:20032312

  2. Relationships of phytomacrofauna to surface area in naturally occurring macrophyte stands

    USGS Publications Warehouse

    Brown, Charles L.; Poe, Thomas P.; French, John R. P., III; Schloesser, Donald W.

    1988-01-01

    Most studies of the relationships between freshwater macrophytes and phytomacrofauna, or the macroinvertebrates associated with the macrophytes, have been based on individual plant collections or samples from monotypic plant stands. We describe the phytomacrofauna assemblages within naturally occurring, taxonomically mixed stands, and consider how macrophyte surface area and plant morphology influenced phytomacrofauna diversity and abundance. Samples of submersed macrophytes and phytomacrofauna were collected April-November 1979 in Anchor Bay of Lake St. Clair. Only the portions of macrophytes within the water column and invertebrates from above the sediment were considered. Densities of phytomacrofauna were not consistently related to fluctuations in macrophyte surface area, indicating that the use of macrophyte structure by the invertebrates changed during the year. Both the abundance and species richness of the phytomacrofauna were strongly related to macrophyte species richness reflecting the response of the invertebrates to the structural heterogeneity in taxonomically mixed stands. Vertically heterogeneous stands with an understory of Chara and an overstory of vascular macrophytes, for example, were likely to contain more invertebrates than stands with only one macrophyte taxon.

  3. Regulatory Initiatives for Control and Release of Technologically Enhanced Naturally-Occurring Radioactive Materials

    SciTech Connect

    Egidi, P.V.

    1999-03-02

    Current drafts of proposed standards and suggested State regulations for control and release of technologically-enhanced naturally-occurring radioactive material (TENORM), and standards for release of volumetrically-contaminated material in the US are reviewed. These are compared to the recommendations of the International Atomic Energy Association (IAEA) Safety Series and the European Commission (EC) proposals. Past regulatory efforts with respect to TENORM in the US dealt primarily with oil-field related wastes. Currently, nine states (AK, GA, LA, MS, NM, OH, OR SC, TX) have specific regulations pertaining to TENORM, mostly based on uranium mill tailings cleanup criteria. The new US proposals are dose- or risk-based, as are the IAEA and EC recommendations, and are grounded in the linear no threshold hypothesis (LNT). TENORM wastes involve extremely large volumes, particularly scrap metal and mine wastes. Costs to control and dispose of these wastes can be considerable. The current debate over the validity of LNT at low doses and low dose rates is particularly germane to this discussion. Most standards setting organizations and regulatory agencies base their recommendations on the LNT. The US Environmental Protection Agency has released a draft Federal Guidance Report that recommends calculating health risks from low-level exposure to radionuclides based on the LNT. However, some scientific and professional organizations are openly questioning the validity of LNT and its basis for regulations, practices, and costs to society in general. It is not clear at this time how a non-linear regulatory scheme would be implemented.

  4. Studies of two naturally occurring compounds which effect release of acetylcholine from synaptosomes. [Leptinotarsa decemlineata

    SciTech Connect

    Koenig, M.L.

    1985-01-01

    Two naturally occurring compounds which effect the release of neurotransmitter from synaptosomes have been purified to apparent homogeneity. Iotrochotin (IOT) isolated from wound exudate of the Caribbean purple bleeder sponge promotes release in a manner that is independent of the extracellular Ca/sup 2 +/ ion concentration. Leptinotarsin (LPT-d), a protein taken from hemolymph of the Colorado potato beetle, Leptinotarsa decemlineata, stimulates Ca/sup 2 +/-dependent release. IOT is slightly acidic and has a molecular weight of approximately 18 kD. (/sup 3/H)acetylcholine which has been introduced into synaptosomes as (/sup 3/H)choline can be released by IOT. The toxin releasable pool of labelled neurotransmitter is not depleted by depolarization of the synaptosomes with high potassium, and therefore seems to be primarily extravesicular. LPT-d is a larger protein (molecular weight = 45 kD) than IOT, and seems to effect primarily vesicular release by opening at least one type of presynaptic Ca/sup 2 +/ channel. The facilitatory effects of the toxin on synaptosomal release can be inhibited by inorganic Ca/sup 2 +/ channel antagonists, but are not generally affected by organic antagonists.

  5. Use of naturally occurring mercury to determine the importance of cutthroat trout to Yellowstone grizzly bears

    USGS Publications Warehouse

    Felicetti, L.A.; Schwartz, C.C.; Rye, R.O.; Gunther, K.A.; Crock, J.G.; Haroldson, M.A.; Waits, L.; Robbins, C.T.

    2004-01-01

    Spawning cutthroat trout (Oncorhynchus clarki (Richardson, 1836)) are a potentially important food resource for grizzly bears (Ursus arctos horribilis Ord, 1815) in the Greater Yellowstone Ecosystem. We developed a method to estimate the amount of cutthroat trout ingested by grizzly bears living in the Yellowstone Lake area. The method utilized (i) the relatively high, naturally occurring concentration of mercury in Yellowstone Lake cutthroat trout (508 ?? 93 ppb) and its virtual absence in all other bear foods (???6 ppb), (ii) hair snares to remotely collect hair from bears visiting spawning cutthroat trout streams between 1997 and 2000, (iii) DNA analyses to identify the individual and sex of grizzly bears leaving a hair sample, (iv) feeding trials with captive bears to develop relationships between fish and mercury intake and hair mercury concentrations, and (v) mercury analyses of hair collected from wild bears to estimate the amount of trout consumed by each bear. Male grizzly bears consumed an average of 5 times more trout/kg bear than did female grizzly bears. Estimated cutthroat trout intake per year by the grizzly bear population was only a small fraction of that estimated by previous investigators, and males consumed 92% of all trout ingested by grizzly bears.

  6. Investigation of the activity level and radiological impacts of naturally occurring radionuclides in blast furnace slag.

    PubMed

    Uğur, F A; Turhan, S; Sahan, H; Sahan, M; Gören, E; Gezer, F; Yeğingil, Z

    2013-01-01

    The activity level and possible radiological impacts of naturally occurring radionuclides on the health of workers and members of the public, as a result of utilisation of blast furnace slag (BFS) samples as a substitute for aggregate in road construction were investigated by using a gamma-ray spectrometer and potential exposure scenarios given in Radiation Protection 122. The mean activity concentrations of the (226)Ra, (232)Th and (40)K in BFS samples were found to be 152.4, 54.9 and 183.1 Bq kg(-1), respectively. These values are compared with typical values measured in BFS samples from the European Union countries, which are 270, 70 and 240 Bq kg(-1) for (226)Ra, (232)Th and (40)K, respectively. The values of radium equivalent activity index calculated for BFS samples were within the recommended safety limits. The highest total annual effective doses evaluated as 0.9 and 0.4 mSv y(-1) for members of the public and workers, respectively, were lower than the annual limit of 1 mSv y(-1). PMID:22826355

  7. A naturally occurring contrast agent for OCT imaging of smokers' lung

    NASA Astrophysics Data System (ADS)

    Yang, Ying; Bagnaninchi, Pierre O.; Whiteman, Suzanne C.; Gey van Pittius, Daniel; El Haj, Alicia J.; Spiteri, Monica A.; Wang, Ruikang K.

    2005-08-01

    Optical coherence tomography (OCT) offers great potential for clinical applications in terms of its cost, safety and real-time imaging capability. Improvement of its resolution for revealing sub-layers or sub-cellular components within a tissue will further widen its application. In this study we report that carbon pigment, which is frequently present in the lungs of smokers, could be used as a contrast agent to improve the OCT imaging of lung tissue. Carbon produced an intense bright OCT image at a relatively deep location. The parallel histopathological section analysis confirmed the presence of carbon pigment in such tissues. The underlying mechanism of the OCT image formation has been discussed based on a model system in which carbon particles were dispersed in agar gel. Calculations and in-depth intensity profiles of OCT revealed that higher refractive index particles with a size close to or smaller than the wavelength would greatly increase backscattering and generate a sharp contrast, while a particle size several times larger than the wavelength would absorb or obstruct the light path. The naturally occurring contrast agent could provide a diagnostic biomarker of lung tissue in smokers. Furthermore, carbon under such circumstances, can be used as an effective exogenous contrast agent, with which specific components or tissues exhibiting early tumour formation can be optically labelled to delineate the location and boundary, providing potential for early cancer detection and its treatment.

  8. Molecular epidemiology of Streptococcus zooepidemicus infection in naturally occurring equine respiratory disease.

    PubMed

    Newton, J R; Laxton, R; Wood, J L N; Chanter, N

    2008-03-01

    The objective of the study was to characterise the molecular epidemiology of Streptococcus zooepidemicus infection among isolates collected sequentially from recently weaned, pasture maintained Welsh mountain ponies with naturally occurring respiratory disease. Weekly nasopharyngeal and tracheal lavage samplings over a 10-week period were conducted in 29 ponies. Two PCR typing methods based on characterisation of the M-protein hypervariable (HV) region and the 16S-23S rRNA gene intergenic spacer were then applied to isolates of S. zooepidemicus recovered from nasopharyngeal swab and tracheal wash samples. S. zooepidemicus infection was highly prevalent during the study, being isolated from 94% of tracheal washes and 88% of nasopharyngeal swabs. Among 39 different S. zooepidemicus types isolated, more were isolated from the trachea (n=33) than the nasopharynx (n=27). There was evidence from temporal patterns of infection for clonal succession over time by the more prevalent S. zooepidemicus types. Novel S. zooepidemicus types were identified, including previously untyped HV regions and intra-strain multiples of both the HV region and intergenic spacer types. PMID:17433734

  9. Speech versus Song: Multiple Pitch-Sensitive Areas Revealed by a Naturally Occurring Musical Illusion

    PubMed Central

    Dick, Fred; Deutsch, Diana; Sereno, Marty

    2013-01-01

    It is normally obvious to listeners whether a human vocalization is intended to be heard as speech or song. However, the 2 signals are remarkably similar acoustically. A naturally occurring boundary case between speech and song has been discovered where a spoken phrase sounds as if it were sung when isolated and repeated. In the present study, an extensive search of audiobooks uncovered additional similar examples, which were contrasted with samples from the same corpus that do not sound like song, despite containing clear prosodic pitch contours. Using functional magnetic resonance imaging, we show that hearing these 2 closely matched stimuli is not associated with differences in response of early auditory areas. Rather, we find that a network of 8 regions, including the anterior superior temporal gyrus (STG) just anterior to Heschl's gyrus and the right midposterior STG, respond more strongly to speech perceived as song than to mere speech. This network overlaps a number of areas previously associated with pitch extraction and song production, confirming that phrases originally intended to be heard as speech can, under certain circumstances, be heard as song. Our results suggest that song processing compared with speech processing makes increased demands on pitch processing and auditory–motor integration. PMID:22314043

  10. Neuroprotective action and free radical scavenging activity of Guttiferone-A, a naturally occurring prenylated benzophenone.

    PubMed

    Nuñez-Figueredo, Y; García-Pupo, L; Ramírez-Sánchez, J; Alcántara-Isaac, Y; Cuesta-Rubio, O; Hernández, R D; Naal, Z; Curti, C; Pardo-Andreu, G L

    2012-12-01

    Reactive oxygen species (ROS) are important mediators in a number of neurodegenerative diseases and molecules capable of scavenging ROS may be a feasible strategy for protecting neuronal cells. We previously demonstrated a powerful iron-chelating action of Guttiferone-A (GA), a naturally occurring polyphenol, on oxidative stress injuries initiated by iron overload. Here we addressed the neuroprotective potential of GA in hydrogen peroxide and glutamate-induced injury on rat's primary culture of cortical neurons and PC12 cells, respectively, and antioxidant properties concerning scavenging and anti-lipoperoxidative activities in cell-free models. The decrease in cell viability induced by each of the toxins, assessed by [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] (MTT) assay, was significantly attenuated by GA. In addition, GA was found to be a potent antioxidant, as shown by (i) inhibition of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical reduction (EC50=20.0 μM), (ii) prevention against chemically or electrochemically generated superoxide radicals, (iii) inhibition of spontaneous brain lipid peroxidation and (iv) interference with the Fenton reaction. These results indicate that GA exerts neuroprotective effects against H2O2 or glutamate toxicity and its antioxidant activity, demonstrated in vitro, could be at least partly involved. They also suggest a promising potential for GA as a therapeutic agent against neurodegenerative diseases involving ROS and oxidative damage. PMID:23115059

  11. Rubemamine and Rubescenamine, Two Naturally Occurring N-Cinnamoyl Phenethylamines with Umami-Taste-Modulating Properties.

    PubMed

    Backes, Michael; Obst, Katja; Bojahr, Juliane; Thorhauer, Anika; Roudnitzky, Natacha; Paetz, Susanne; Reichelt, Katharina V; Krammer, Gerhard E; Meyerhof, Wolfgang; Ley, Jakob P

    2015-10-01

    Sensory screening of a series of naturally occurring N-cinnamoyl derivatives of substituted phenethylamines revealed that rubemamine (9, from Chenopodium album) and rubescenamine (10, from Zanthoxylum rubsecens) elicit strong intrinsic umami taste in water at 50 and 10 ppm, respectively. Sensory tests in glutamate- and nucleotide-containing bases showed that the compounds influence the whole flavor profile of savory formulations. Both rubemamine (9) and rubescenamine (10) at 10-100 ppm dose-dependently positively modulated the umami taste of MSG (0.17-0.22%) up to threefold. Among the investigated amides, only rubemamine (9) and rubescenamine (10) are able to directly activate the TAS1R1-TAS1R3 umami taste receptor. Moreover, both compounds also synergistically modulated the activation of TAS1R1-TAS1R3 by MSG. Most remarkably, rubemamine (9) was able to further positively modulate the IMP-enhanced TAS1R1-TAS1R3 response to MSG ? 1.8-fold. Finally, armatamide (11), zanthosinamide (13), and dioxamine (14), which lack intrinsic umami taste in vivo and direct receptor response in vitro, also positively modulated receptor activation by MSG about twofold and the IMP-enhanced MSG-induced TAS1R1-TAS1R3 responses approximately by 50%. In sensory experiments, dioxamine (14) at 25 ppm in combination with 0.17% MSG exhibited a sensory equivalent to 0.37% MSG. PMID:26375852

  12. Microbial utilization of naturally occurring hydrocarbons at the Guaymas Basin hydrothermal vent site

    SciTech Connect

    Bazylinski, D.A.; Wirsen, C.O.; Jannasch, H.W. )

    1989-11-01

    The Guaymas Basin (Gulf of California; depth, 2,000 m) is a site of hydrothermal activity in which petroliferous materials is formed by thermal alteration of deposited planktonic and terrestrial organic matter. We investigated certain components of these naturally occurring hydrocarbons as potential carbon sources for a specific microflora at these deep-sea vent sites. Respiratory conversion of (1-{sup 14}C)hexadecane and (1(4,5,8)-{sup 14}C)naphthalene to {sup 14}CO{sub 2} was observed at 4{degree}C and 25{degree}C, and some was observed at 55{degree}C, but none was observed at 80{degree}C. Bacterial isolates were capable of growing on both substrates as the sole carbon source. All isolates were aerobic and mesophilic with respect to growth on hydrocarbons but also grew at low temperatures (4 to 5{degree}C). These results correlate well with previous geochemical analyses, indicating microbial hydrocarbon degradation, and show that at least some of the thermally produced hydrocarbons at Guaymas Basin are significant carbon sources to vent microbiota.

  13. Recombinant Moraxella bovoculi cytotoxin-ISCOM matrix adjuvanted vaccine to prevent naturally occurring infectious bovine keratoconjunctivitis.

    PubMed

    Angelos, John A; Lane, V Michael; Ball, Louise M; Hess, John F

    2010-03-01

    A randomized, blinded, controlled field trial was conducted during summer 2006 in a northern California, USA, herd of beef cattle to evaluate the efficacy of a recombinant Moraxella bovoculi cytotoxin subunit vaccine to prevent naturally occurring infectious bovine keratoconjunctivitis (IBK; pinkeye). A convenience sample comprised of 127 steers were administered a subcutaneous dose of either adjuvant alone (ISCOM matrices; control group) or recombinant M. bovoculi cytotoxin carboxy terminus adjuvanted with ISCOM matrices (MbvA group) and were boostered 21 days later. The steers were examined once weekly for 15 weeks for evidence of IBK. No significant difference in the cumulative proportion of corneal ulcerations was detected between groups. Compared to the control calves, the MbvA vaccinates had significantly higher increases in serum neutralizing titers to M. bovoculi hemolysin between week 0 and week 6. The prevalence of M. bovis isolations was higher from ulcerated eyes of calves vaccinated with MbvA as compared to control calves. Vaccination of calves against the carboxy terminus of M. bovoculi RTX toxin resulted in significant increases in serum hemolysin neutralizing titers and may modulate organism type cultured from ulcerated eyes of calves in herds where both M. bovis and M. bovoculi exist. Use of M. bovoculi antigens alone in vaccines to prevent IBK may not be beneficial in herds where IBK is associated with both M. bovoculi and M. bovis. PMID:20217228

  14. Masculinised Behaviour of XY Females in a Mammal with Naturally Occuring Sex Reversal

    PubMed Central

    Saunders, Paul A.; Franco, Thomas; Sottas, Camille; Maurice, Tangui; Ganem, Guila; Veyrunes, Frédéric

    2016-01-01

    Most sex differences in phenotype are controlled by gonadal hormones, but recent work on laboratory strain mice that present discordant chromosomal and gonadal sex showed that sex chromosome complement can have a direct influence on the establishment of sex-specific behaviours, independently from gonads. In this study, we analyse the behaviour of a rodent with naturally occurring sex reversal: the African pygmy mouse Mus minutoides, in which all males are XY, while females are of three types: XX, XX* or X*Y (the asterisk represents an unknown X-linked mutation preventing masculinisation of X*Y embryos). X*Y females show typical female anatomy and, interestingly, have greater breeding performances. We investigate the link between sex chromosome complement, behaviour and reproductive success in females by analysing several behavioural features that could potentially influence their fitness: female attractiveness, aggressiveness and anxiety. Despite sex chromosome complement was not found to impact male mate preferences, it does influence some aspects of both aggressiveness and anxiety: X*Y females are more aggressive than the XX and XX*, and show lower anxiogenic response to novelty, like males. We discuss how these behavioural differences might impact the breeding performances of females, and how the sex chromosome complement could shape the differences observed. PMID:26964761

  15. Naturally occurring p16(Ink4a)-positive cells shorten healthy lifespan.

    PubMed

    Baker, Darren J; Childs, Bennett G; Durik, Matej; Wijers, Melinde E; Sieben, Cynthia J; Zhong, Jian; Saltness, Rachel A; Jeganathan, Karthik B; Verzosa, Grace Casaclang; Pezeshki, Abdulmohammad; Khazaie, Khashayarsha; Miller, Jordan D; van Deursen, Jan M

    2016-02-11

    Cellular senescence, a stress-induced irreversible growth arrest often characterized by expression of p16(Ink4a) (encoded by the Ink4a/Arf locus, also known as Cdkn2a) and a distinctive secretory phenotype, prevents the proliferation of preneoplastic cells and has beneficial roles in tissue remodelling during embryogenesis and wound healing. Senescent cells accumulate in various tissues and organs over time, and have been speculated to have a role in ageing. To explore the physiological relevance and consequences of naturally occurring senescent cells, here we use a previously established transgene, INK-ATTAC, to induce apoptosis in p16(Ink4a)-expressing cells of wild-type mice by injection of AP20187 twice a week starting at one year of age. We show that compared to vehicle alone, AP20187 treatment extended median lifespan in both male and female mice of two distinct genetic backgrounds. The clearance of p16(Ink4a)-positive cells delayed tumorigenesis and attenuated age-related deterioration of several organs without apparent side effects, including kidney, heart and fat, where clearance preserved the functionality of glomeruli, cardio-protective KATP channels and adipocytes, respectively. Thus, p16(Ink4a)-positive cells that accumulate during adulthood negatively influence lifespan and promote age-dependent changes in several organs, and their therapeutic removal may be an attractive approach to extend healthy lifespan. PMID:26840489

  16. Naturally Occurring Radioactive Materials in Coals and Coal Combustion Residuals in the United States.

    PubMed

    Lauer, Nancy E; Hower, James C; Hsu-Kim, Heileen; Taggart, Ross K; Vengosh, Avner

    2015-09-15

    The distribution and enrichment of naturally occurring radioactive materials (NORM) in coal combustion residuals (CCRs) from different coal source basins have not been fully characterized in the United States. Here we provide a systematic analysis of the occurrence of NORM ((232)Th, (228)Ra, (238)U, (226)Ra, and (210)Pb) in coals and associated CCRs from the Illinois, Appalachian, and Powder River Basins. Illinois CCRs had the highest total Ra ((228)Ra + (226)Ra = 297 46 Bq/kg) and the lowest (228)Ra/(226)Ra activity ratio (0.31 0.09), followed by Appalachian CCRs (283 34 Bq/kg; 0.67 0.09), and Powder River CCRs (213 21 Bq/kg; 0.79 0.10). Total Ra and (228)Ra/(226)Ra variations in CCRs correspond to the U and Th concentrations and ash contents of their feed coals, and we show that these relationships can be used to predict total NORM concentrations in CCRs. We observed differential NORM volatility during combustion that results in (210)Pb enrichment and (210)Pb/(226)Ra ratios greater than 1 in most fly-ash samples. Overall, total NORM activities in CCRs are 7-10- and 3-5-fold higher than NORM activities in parent coals and average U.S. soil, respectively. This study lays the groundwork for future research related to the environmental and human health implications of CCR disposal and accidental release to the environment in the context of this elevated radioactivity. PMID:26328894

  17. Anabolic and Antiresorptive Modulation of Bone Homeostasis by the Epigenetic Modulator Sulforaphane, a Naturally Occurring Isothiocyanate.

    PubMed

    Thaler, Roman; Maurizi, Antonio; Roschger, Paul; Sturmlechner, Ines; Khani, Farzaneh; Spitzer, Silvia; Rumpler, Monika; Zwerina, Jochen; Karlic, Heidrun; Dudakovic, Amel; Klaushofer, Klaus; Teti, Anna; Rucci, Nadia; Varga, Franz; van Wijnen, Andre J

    2016-03-25

    Bone degenerative pathologies like osteoporosis may be initiated by age-related shifts in anabolic and catabolic responses that control bone homeostasis. Here we show that sulforaphane (SFN), a naturally occurring isothiocyanate, promotes osteoblast differentiation by epigenetic mechanisms. SFN enhances active DNA demethylation viaTet1andTet2and promotes preosteoblast differentiation by enhancing extracellular matrix mineralization and the expression of osteoblastic markers (Runx2,Col1a1,Bglap2,Sp7,Atf4, andAlpl). SFN decreases the expression of the osteoclast activator receptor activator of nuclear factor-κB ligand (RANKL) in osteocytes and mouse calvarial explants and preferentially induces apoptosis in preosteoclastic cells via up-regulation of theTet1/Fas/Caspase 8 and Caspase 3/7 pathway. These mechanistic effects correlate with higher bone volume (∼20%) in both normal and ovariectomized mice treated with SFN for 5 weeks compared with untreated mice as determined by microcomputed tomography. This effect is due to a higher trabecular number in these mice. Importantly, no shifts in mineral density distribution are observed upon SFN treatment as measured by quantitative backscattered electron imaging. Our data indicate that the food-derived compound SFN epigenetically stimulates osteoblast activity and diminishes osteoclast bone resorption, shifting the balance of bone homeostasis and favoring bone acquisition and/or mitigation of bone resorptionin vivo Thus, SFN is a member of a new class of epigenetic compounds that could be considered for novel strategies to counteract osteoporosis. PMID:26757819

  18. Antioxidant effect of naturally occurring xanthines on the oxidative damage of DNA bases

    NASA Astrophysics Data System (ADS)

    Vieira, A. J. S. C.; Telo, J. P.; Pereira, H. F.; Patrocnio, P. F.; Dias, R. M. B.

    1999-01-01

    The repair of the oxidised radicals of adenine and guanosine by several naturally occurring xanthines was studied. Each pair of DNA purine/xanthine was made to react with the sulphate radical and the decrease of the concentration of both compounds was measured by HPLC as a function of irradiation time. The results show that xanthine efficiently prevents the oxidation of the two DNA purines. Theophyline and paraxanthine repair the oxidised radical of adenine but not the one from guanosine. Theobromine and caffeine do not show any protecting effect. An order of the oxidation potentials of all the purines studied is proposed. La rparation des radicaux oxyds de l'adnine et de la guanosine par des xanthines naturelles a t tudie en soumettant chaque paire base de l'ADN/xanthine l'oxydation par le radical sulfate et en mesurant par HPLC la disparition des deux composs en fonction du temps d'irradiation. Les rsultats montrent que la xanthine joue un rle protecteur efficace contre l'oxydation des deux purines de l'ADN. La thophyline et la paraxanthine rparent le radical oxyd de l'adnine mais pas celui de la guanosine. La thobromine et la cafene n'ont pas d'effet protecteur. Un ordre de potentiels d'oxydation des purines tudies est propos.

  19. Endotoxemia and tumor necrosis factor activity in dogs with naturally occurring parvoviral enteritis.

    PubMed

    Otto, C M; Drobatz, K J; Soter, C

    1997-01-01

    A prospective, nonrandomized study was performed to evaluate the role of endotoxin and tumor necrosis factor (TNF) in dogs with parvoviral enteritis. Seventeen dogs with naturally occurring parvoviral enteritis were enrolled in the study. Plasma samples were obtained for quantification of endotoxin and TNF on presentation and at 3 and 6 hours after therapy with either fluids prior to antibiotics, or fluids concurrently with antibiotics. All dogs received standard supportive therapy. Fourteen of 17 dogs had endotoxin in their plasma during the study period; 7 of 17 dogs had measurable TNF. No endotoxin or TNF was detectable in plasma from normal puppies. An increase in TNF activity was predictive of mortality (P = .041). There was a trend for increasing endotoxin activity to predict mortality (P = .0769). Animals that received antibiotics with fluids were significantly older than those that received fluids prior to antibiotics, and there was a trend for animals that received antibiotics with fluids to have a decrease in endotoxin activity after treatment (P = .054). Endotoxin and activation of the cytokine cascade are integral to the pathophysiology of parvoviral enteritis. Measures to limit endotoxemia and the systemic inflammatory response may improve survival. PMID:9127292

  20. An overview of naturally occurring radioactive materials (NORM) in the petroleum industry

    SciTech Connect

    Smith, K.P.

    1992-12-01

    Oil and gas extraction and processing operations sometimes accumulate naturally occurring radioactive materials (NORM) at concentrations above normal in by-product waste streams. Results from NORM surveys indicate that radionuclide concentrations can be quite variable, ranging from undetectable to extremely high levels. To date, efforts to characterize the geographic distribution of NORM have been limited by poor statistical representation. In addition, the fate of NORM in the environment has not been fully defined, and few human health risk assessment have been conducted. Both the petroleum industry and regulators are becoming increasingly concerned about the presence of NORM. At present, most existing federal environmental regulations do not address oil and gas NORM, and only a few states have developed regulatory programs. Available data suggest that the occurrence of NORM (and associated health risks) is significant enough to warrant increased regulatory control. However, before these regulations can be developed, additional research is needed to (1) better characterize the occurrence and distribution of NORM throughout the industry, (2) quantify hazards posed by NORM to industry workers and the general public, and (3) develop effective waste treatment and minimization technologies that will lower the risk associated with NORM and reduce disposal costs.

  1. Inhibition of tau aggregation using a naturally-occurring cyclic peptide scaffold.

    PubMed

    Wang, Conan K; Northfield, Susan E; Huang, Yen-Hua; Ramos, Mariana C; Craik, David J

    2016-02-15

    Disulfide-rich macrocyclic peptides are emerging as versatile scaffolds for the development of stable biochemical tools. This potential is due to the combination of their structural stability and range of bioactivities. Here, we explored the activity of these peptides on fibril growth of the hexapeptide Ac-VQIVYK-NH2 (AcPHF6), which is a tau-derived peptide that has been widely used to understand the pathological mechanism of numerous tauopathies, including Alzheimer's disease. Of the cyclic peptides tested, SFTI-1 and kB1 showed an inherent ability to inhibit AcPHF6 fibril formation. Using an end-capping strategy and combining it with a molecular grafting approach, we demonstrated that SFTI-1 could be used as a starting point to design more potent fibril inhibitors. We further identified chemical and structural features of SFTI-1 and its analogues that underpin their inhibitory activity. The ability to inhibit fibril growth using the strategy employed herein supports the 'steric zipper' model of AcPHF6 fibril formation and shows that naturally-occurring cyclic peptides have potential as drug leads or molecular probes for understanding fibril formation. PMID:26807864

  2. Formation of naturally occurring pigments during the production of nitrite-free dry fermented sausages.

    PubMed

    De Maere, Hannelore; Fraeye, Ilse; De Mey, Eveline; Dewulf, Lore; Michiels, Chris; Paelinck, Hubert; Chollet, Sylvie

    2016-04-01

    This study investigates the potential of producing red coloured dry fermented sausages without the addition of nitrite and/or nitrate. Therefore, the formation of zinc protoporphyrin IX (Zn(II)PPIX) as naturally occurring pigment, and the interrelated protoporphyrin IX (PPIX) and heme content were evaluated during nitrite-free dry fermented sausage production at different pH conditions. Zn(II)PPIX was only able to form in dry fermented sausages at pH conditions higher than approximately 4.9. Additionally, the presence of Zn(II)PPIX increased drastically at the later phase of the production process (up to day 177), confirming that in addition to pH, time is also a crucial factor for its formation. Similarly, PPIX also accumulated in the meat products at increased pH conditions and production times. In contrast, a breakdown of heme was observed. This breakdown was more gradual and independent of pH and showed no clear relationship with the formed amounts of Zn(II)PPIX and PPIX. A statistically significant relationship between Zn(II)PPIX formation and product redness was established. PMID:26686009

  3. Polyhydroxyester films obtained by non-catalyzed melt-polycondensation of natural occurring fatty polyhydroxyacids.

    NASA Astrophysics Data System (ADS)

    Benitez, Jose; Heredia-Guerrero, José; Guzman-Puyol, Susana; Barthel, Markus; Dominguez, Eva; Heredia, Antonio

    2015-08-01

    Free-standing polyesters films from mono and polyhydroxylated fatty acids (C16 and C18) have been obtained by non-catalyzed melt-condensation polymerization in air at 150°C. Chemical characterization by Fourier Transform Infrared Spectroscopy (FTIR) and 13C Magic Angle Spinning Nuclear Magnetic Resonance (13C MAS-NMR) has confirmed the formation of the corresponding esters and the occurrence of hydroxyl partial oxidation which extent depends on the type of hydroxylation of the monomer (primary or secondary). Generally, polyester films obtained are hydrophobic, insoluble in common solvents, amorphous and infusible as revealed by X-ray Diffraction (XRD) and Differential Scanning Calorimetry (DSC). In ?-polyhydroxy acids, esterification reaction with primary hydroxyls is preferential and, therefore, the structure can be defined as linear with variable branching depending on the amount of esterified secondary hydroxyls. The occurrence side oxidative reactions like the diol cleavage are responsible for chain cross-linking. Films are thermally stable up to 200-250°C though this limit can be extended up to 300°C in the absence of ester bonds involving secondary hydroxyls. By analogy with natural occurring fatty polyesters (i.e. cutin in higher plants) these polymers are proposed as biodegradable and non-toxic barrier films or coatings to be used, for instance, in food packing

  4. A quantitative analysis of microbially-induced calcite precipitation employing artificial and naturally-occurring sediments

    NASA Astrophysics Data System (ADS)

    Lokier, Stephen; Krieg Dosier, Ginger

    2013-04-01

    Microbially-induced calcite precipitation is a strong candidate for the production of sustainable construction materials. The process employs the microbe Sporosarcina pasteurii as an agent to microbially mediate the precipitation of calcium carbonate to bind unconsolidated sediment. As this process can be achieved under ambient temperature conditions and can utilise a wide variety of easily-available sediments, potentially including waste materials, it is envisioned that this procedure could significantly reduce carbon-dioxide emissions in the construction industry. This study describes and quantifies the precipitation of calcite cement in a range of naturally-occurring sediments compared with a control matrix. The study establishes the optimum treatment time for effective cement precipitation in order to produce a material that meets the standards required for construction whilst keeping economic and environmental outlays at a minimum. The 'control sediment' employed industrial-grade glass beads with a grain size range of 595-1180 microns (16-30 US mesh). Sporosarcina pasteurii were mixed in a solution of urea and calcium chloride and then inoculated into the control sediment. The microbes attach to the surface of the sediment grains and employ urea as a source of energy to produce ammonia and carbon dioxide. By so doing, they increase the pH of the solution allowing calcium carbonate to precipitate at the cell walls to act as nucleation points facilitating the precipitation of cements as a grain-coating and biocementing the unconsolidated sediment. The solution treatment was repeated at eight hour intervals with samples removed for detailed analysis after each every five consecutive treatments (i.e. 40 hours). The process was repeated to produce 20 samples with treatment times between 40 and 800 hours. Cemented samples were impregnated with blue epoxy and examined petrographically to monitor cement development. Modal analysis was undertaken on each cemented sample to establish the abundance and natures of precipitated cements. Samples were also examined via SEM to monitor cement distribution and quantify the thickness of cements on grain surfaces and at grain-on-grain contacts. Analysis established that precipitation of calcite continues until 400 hours (50 treatments) after which time there is only an insignificant precipitation of new calcite cement. This is inferred to result from the occlusion of porosity (from 40% to 10%) and observed calcite precipitation at grain-on-grain contacts, both factors reduce the permeability of the samples and, thus, inhibit the flow of solution through the medium. The precipitated calcite cement was found to be dominantly grain-rimming with a consistent thickness averaging 11 microns. A range of naturally-occurring sediments were collected from surface locations throughout the United Arab Emirates. Samples were submitted to a range of petrographic and geochemical analysis in order to quantify grain-size distribution, grain composition and bulk total carbonate content (7.5-94 wt%). Sub-samples of these sediments were established by sieving and the cementation potential of different size fractions was established. Following treatment, these samples were submitted to the same analysis as those employed for the control sediment. A relationship between both sediment grain-size characteristics and sediment grain composition to cement precipitation was established and is discussed.

  5. Isotopic analysis of uranium in natural waters by alpha spectrometry

    USGS Publications Warehouse

    Edwards, K.W.

    1968-01-01

    A method is described for the determination of U234/U238 activity ratios for uranium present in natural waters. The uranium is coprecipitated from solution with aluminum phosphate, extracted into ethyl acetate, further purified by ion exchange, and finally electroplated on a titanium disc for counting. The individual isotopes are determined by measurement of the alpha-particle energy spectrum using a high resolution low-background alpha spectrometer. Overall chemical recovery of about 90 percent and a counting efficiency of 25 percent allow analyses of water samples containing as little as 0.10 ?g/l of uranium. The accuracy of the method is limited, on most samples, primarily by counting statistics.

  6. Characterization of naturally occurring radioactive materials in Libyan oil pipe scale using a germanium detector and Monte Carlo simulation

    NASA Astrophysics Data System (ADS)

    Habib, A. S.; Shutt, A. L.; Regan, P. H.; Matthews, M. C.; Alsulaiti, H.; Bradley, D. A.

    2014-02-01

    Radioactive scale formation in various oil production facilities is acknowledged to pose a potential significant health and environmental issue. The presence of such an issue in Libyan oil fields was recognized as early as 1998. The naturally occurring radioactive materials (NORM) involved in this matter are radium isotopes (226Ra and 228Ra) and their decay products, precipitating into scales formed on the surfaces of production equipment. A field trip to a number of onshore Libyan oil fields has indicated the existence of elevated levels of specific activity in a number of locations in some of the more mature oil fields. In this study, oil scale samples collected from different parts of Libya have been characterized using gamma spectroscopy through use of a well shielded HPGe spectrometer. To avoid potential alpha-bearing dust inhalation and in accord with safe working practices at this University, the samples, contained in plastic bags and existing in different geometries, are not permitted to be opened. MCNP, a Monte Carlo simulation code, is being used to simulate the spectrometer and the scale samples in order to obtain the system absolute efficiency and then to calculate sample specific activities. The samples are assumed to have uniform densities and homogeneously distributed activity. Present results are compared to two extreme situations that were assumed in a previous study: (i) with the entire activity concentrated at a point on the sample surface proximal to the detector, simulating the sample lowest activity, and; (ii) with the entire activity concentrated at a point on the sample surface distal to the detector, simulating the sample highest activity.

  7. Managing for Successful Control of Naturally Occurring Asbestos During Large Scale Grading

    NASA Astrophysics Data System (ADS)

    Saur, R.; Harnish, D.; Cavanaugh, J.; Kendall, K.; Virdee, A.; Ludlam, D.

    2012-12-01

    Pacific Gas and Electric Company recently completed environmental remediation and civil grading of a 35-acre site in San Francisco Bay Area, and the project became recognized with local agencies as having excellent controls systems for naturally-occurring asbestos (NOA). The project began in 2010 and was completed in 2012, and involved excavating and grading over 100,000 tons of soil containing NOA. The work was subject to requirements by state, local and regional agencies, including an asbestos dust mitigation plan for the Bay Area Air Quality Management District. Effective control of NOA is attributed to management approaches combined with effective monitoring and state-of-the-art controls. Management Planning. The contract for construction specified NOA compliance management and controls, including having a NOA-control "czar" ultimately responsible for effective mitigation. An important element was daily pre-planning for excavation/grading that involved both the NOA mitigation experts and construction staff. Personnel Planning and Training. All construction personnel were trained before work regarding NOA hazards and mitigations. Daily tailboards with all construction personnel included discussions of the NOA controls integral to the daily work. Supervision. A NOA mitigation compliance leader was assigned to each excavation operation, responsible for continuously monitoring wind direction and work to ensure mitigation met requirements, and that disturbed areas were hydrosealed or covered. Adaptive Management - Daily and weekly debriefs occurred with those responsible for NOA controls to evaluate effectiveness, and identify improvements needed. If a monitoring result exceeded the project trigger level, work shut down and a root-cause analysis was performed to determine appropriate corrective actions. Deviations of results from background were researched as to cause, and any adjustments identified. Nearby non-project activities were monitored, as they occasionally caused trigger level exceedences in perimeter monitors, including from off-site vehicles, nearby construction, and mechanical vegetation management (e.g. weed whacking). Regulatory and Owner Oversight. Monitoring results were reported daily to agencies, agencies made frequent inspections, and owner's independent compliance representatives observed the NOA mitigation and provided real-time feedback to the construction team. NOA Controls. NOA emissions were controlled site-wide and for each work activity. Site systems included misting, water trucks on roads, temporary covers and soil sealants. Work activity controls for excavation/grading included both source and perimeter controls. Water application technologies specially designed for NOA fiber mitigation, and not just dust mitigation, were effective without adding excessive water to work areas. These activities collectively created a management structure that facilitated successful implementation of NOA control technologies.

  8. Immobilization and orientation-dependent activity of a naturally occurring antimicrobial peptide.

    PubMed

    Soares, Jason W; Kirby, Romy; Doherty, Laurel A; Meehan, Alexa; Arcidiacono, Steven

    2015-08-01

    A naturally occurring antimicrobial peptide, SMAP-29, was synthesized with an n-terminal or c-terminal cysteine, termed c_SMAP and SMAP_c, respectively, for site-directed immobilization to superparamagnetic beads. Immobilized SMAP orientation-dependent activity was probed against multiple bacteria of clinical interest including Acinetobacter baumannii, Pseudomonas aeruginosa, Bacillus anthracis sterne and Staphylococcus aureus. A kinetic microplate assay was employed to reveal both concentration and time-dependent activity for elucidation of minimum bactericidal concentration (MBC) and sub-lethal effects. Immobilized SMAP activity was equivalent or reduced compared with soluble SMAP_c and c_SMAP regardless of immobilization orientation, with only one exception. A comparison of immobilized SMAP_c and c_SMAP activity revealed a bacteria-specific potency dependent on immobilization orientation, which was contrary to that seen in solution, wherein SMAP_c was more potent against all bacteria than c_SMAP. Sub-MBC kinetic studies displayed the influence of peptide exposure to the cells with multiple bacteria exhibiting increased susceptibility and efficacy at lower concentrations upon extended exposure (i.e. MBC enhancement). For instances in which complete killing was not achieved, two predominant effects were evident: retardation of growth rate and an increased lag phase. Both effects, seen independently and concomitantly, indicate some degree of induced cellular damage that can serve as a predictor toward eventual cell death. SMAP_c immobilized on glass through standard silanization chemistry was also investigated to ascertain the influence of substrate on activity against select bacteria. PMID:26018607

  9. Effect of naturally occurring isothiocyanates in the inhibition of cyclophosphamide-induced urotoxicity.

    PubMed

    Manesh, C; Kuttan, G

    2005-06-01

    Cyclophosphamide-induced urotoxiciy was reduced in Swiss albino mice by the treatment of naturally occurring isothiocyanates such as AITC or PITC (25 microg/dose/animal, i.p.) for 5 days along with CTX (1.5 mmol/kg body wt.; i.p.). Severely inflamed and dark coloured urinary bladders of the CTX alone treated animals were found to be normalized on morphological analysis by the treatment of AITC or PITC. Urine protein levels were reduced by the treatment with AITC (6.2 +/- 0.37 g/l) and PITC (6.56 +/- 1.56 g/l), which was elevated by CTX administration (8.66 +/- 0.47 g/l). Urine urea N2 that was enhanced significantly by CTX administration (26.87 +/- 1.86 g/l) was reduced by treatment with both AITC (17.38 +/- 0.06 g/l) and PITC (15.85 +/- 1.56 g/l). GSH content, which was drastically reduced by CTX administration in both bladder (0.87 +/- 0.1 nmol/mg protein) and liver (2.47 +/- 0.6 nmol/mg protein) was enhanced by treatment with AITC and PITC both in bladder (AITC- 3.65 +/- 0.18 nmol/mg protein; PITC- 2.8 +/- 0.15 nmol/mg protein) and in liver (AITC- 4.10 +/- 0.81 nmol/mg protein; PITC- 4.70 +/- 0.44 nmol/mg protein). Histopathology of the bladders of CTX alone treated group showed severe necrosis of the tissue whereas AITC and PITC treated group showed normal bladder pathology. PMID:16008126

  10. Initial evaluation of nighttime restlessness in a naturally occurring canine model of osteoarthritis pain

    PubMed Central

    Knazovicky, David; Tomas, Andrea; Motsinger-Reif, Alison

    2015-01-01

    Chronic pain due to osteoarthritis (OA) can lead to significant disruption of sleep and increased restlessness. Our objective was to assess whether naturally occurring canine OA is associated with nighttime restlessness and so has potential as a model of OA-associated sleep disturbance. The study was designed as a two-part prospective masked, placebo-controlled study using client-owned dogs (Part A n = 60; Part B n = 19). Inclusion criteria consisted of OA-associated joint pain and mobility impairment. The primary outcome measure for both parts was nighttime accelerometry. In Part B, quality of sleep was assessed using a clinical metrology instrument (Sleep and Night Time Restlessness Evaluation Score, SNoRE). Part A included dogs receiving two weeks of non-steroidal anti-inflammatory drug (NSAID) preceded with two weeks of no treatment. Part B was a crossover study, with NSAID/placebo administered for two weeks followed by a washout period of one week and another two weeks of NSAID/placebo. Repeated measures analysis of variance was used to assess differences between baseline and treatment. There were no significant changes in accelerometry-measured nighttime activity as a result of NSAID administration. SNoRE measures indicated significant improvements in aspects of the quality of nighttime sleep that did not involve obvious movement. These results reflect the few similar studies in human OA patients. Although accelerometry does not appear to be useful, this model has potential to model the human pain-related nighttime sleep disturbance, and other outcome measures should be explored in this model. PMID:25722957

  11. Assessment of radiological hazards of naturally occurring radioactive materials in cement industry.

    PubMed

    Aslam, Muhammad; Gul, Rahmat; Ara, Tauseef; Hussain, Manzur

    2012-09-01

    A study on the radiological hazard in Portland cement due to the presence of naturally occurring radioactive materials is being carried out. The Portland cement manufactured in the Islamabad/Rawalpindi region of Pakistan, intermediate products (clinker) and the various raw materials which compose the product have been analysed for (226)Ra, (232)Th and (40)K using a gamma spectrometry system with a N-type high-purity germanium detector of 80 % relative efficiency. From the measured gamma ray spectra, specific activities were determined. The mean values of the total specific activity of (226)Ra, (232)Th and (40)K are 34.211.9, 29.13.6 and 295.166.9 Bq kg(-1), respectively in Portland cement, 28.48.7, 11.31.7 and 63.117.3 Bq kg(-1), respectively in lime stone, 8.21.9, 16.23.9 and 187.753.2 Bq kg(-1), respectively in gypsum, 34.713.1, 41.26.7 and 187.617.2 Bq kg(-1), respectively in clay, 41.111.8, 39.36.9 and 195.129.2 Bq kg(-1), respectively in latrite and 51.118.2, 23.21.2 and 258.415.3 Bq kg(-1), respectively in clinker. The radium equivalent activities (Ra(eq)), external hazard index (H(ex)), internal hazard index (H(in)), absorbed dose rate in air (D) and annual effective dose rate (E(eff)) were also determined. The measured activity concentrations for these radio nuclides and radiological indices were compared with the reported national and international data. All these measured values are comparable with the worldwide data reported in UNSCEAR publications. PMID:22355168

  12. Estimated trichloroethene transformation rates due to naturally occurring biodegradation in a fractured-rock aquifer

    USGS Publications Warehouse

    Chapelle, Francis H.; Lacombe, Pierre J.; Bradley, Paul M.

    2012-01-01

    Rates of trichloroethene (TCE) mass transformed by naturally occurring biodegradation processes in a fractured rock aquifer underlying a former Naval Air Warfare Center (NAWC) site in West Trenton, New Jersey, were estimated. The methodology included (1) dividing the site into eight elements of equal size and vertically integrating observed concentrations of two daughter products of TCE biodegradationcis-dichloroethene (cis-DCE) and chlorideusing water chemistry data from a network of 88 observation wells; (2) summing the molar mass of cis-DCE, the first biodegradation product of TCE, to provide a probable underestimate of reductive biodegradation of TCE, (3) summing the molar mass of chloride, the final product of chlorinated ethene degradation, to provide a probable overestimate of overall biodegradation. Finally, lower and higher estimates of aquifer porosities and groundwater residence times were used to estimate a range of overall transformation rates. The highest TCE transformation rates estimated using this procedure for the combined overburden and bedrock aquifers was 945 kg/yr, and the lowest was 37 kg/yr. However, hydrologic considerations suggest that approximately 100 to 500 kg/yr is the probable range for overall TCE transformation rates in this system. Estimated rates of TCE transformation were much higher in shallow overburden sediments (approximately 100 to 500 kg/yr) than in the deeper bedrock aquifer (approximately 20 to 0.15 kg/yr), which reflects the higher porosity and higher contaminant mass present in the overburden. By way of comparison, pump-and-treat operations at the NAWC site are estimated to have removed between 1,073 and 1,565 kg/yr of TCE between 1996 and 2009.

  13. Effect of leachability on environmental risk assessment for naturally occurring radioactive materials in petroleum oil fields.

    PubMed

    Rajaretnam, G; Spitz, H B

    2000-02-01

    Elevated concentrations of naturally occurring radioactive material (NORM), including 238U, 232Th, and their progeny found in underground geologic deposits, are often encountered during crude oil recovery. Radium, the predominant radionuclide brought to the surface with the crude oil and produced water, co-precipitates with barium in the form of complex compounds of sulfates, carbonates, and silicates found in sludge and scale. These NORM deposits are highly stable and very insoluble under ambient conditions at the earth's surface. However, the co-precipitated radium matrix is not thermodynamically stable at reducing conditions which may enable a fraction of the radium to eventually be released to the environment. Although the fate of radium in uranium mill tailings has been studied extensively, the leachability of radium from crude oil NORM deposits exposed to acid-rain and other aging processes is generally unknown. The leachability of radium from NORM contaminated soil collected at a contaminated oil field in eastern Kentucky was determined using extraction fluids having wide range of pH reflecting different extreme environmental conditions. The average 226Ra concentration in the samples of soil subjected to leachability testing was 32.56 Bq g(-1) +/- 0.34 Bq g(-1). The average leaching potential of 226Ra observed in these NORM contaminated soil samples was 1.3% +/- 0.46% and was independent of the extraction fluid. Risk assessment calculations using the family farm scenario show that the annual dose to a person living and working on this NORM contaminated soil is mainly due to external gamma exposure and radon inhalation. However, waterborne pathways make a non-negligible contribution to the dose for the actual resident families living on farmland with the type of residual NORM contamination due to crude oil recovery operations. PMID:10647985

  14. Forecasting Seizures Using Intracranial EEG Measures and SVM in Naturally Occurring Canine Epilepsy

    PubMed Central

    Brinkmann, Benjamin H.; Patterson, Edward E.; Vite, Charles; Vasoli, Vincent M.; Crepeau, Daniel; Stead, Matt; Howbert, J. Jeffry; Cherkassky, Vladimir; Wagenaar, Joost B.; Litt, Brian; Worrell, Gregory A.

    2015-01-01

    Management of drug resistant focal epilepsy would be greatly assisted by a reliable warning system capable of alerting patients prior to seizures to allow the patient to adjust activities or medication. Such a system requires successful identification of a preictal, or seizure-prone state. Identification of preictal states in continuous long- duration intracranial electroencephalographic (iEEG) recordings of dogs with naturally occurring epilepsy was investigated using a support vector machine (SVM) algorithm. The dogs studied were implanted with a 16-channel ambulatory iEEG recording device with average channel reference for a mean (st. dev.) of 380.4 (+87.5) days producing 220.2 (+104.1) days of intracranial EEG recorded at 400 Hz for analysis. The iEEG records had 51.6 (+52.8) seizures identified, of which 35.8 (+30.4) seizures were preceded by more than 4 hours of seizure-free data. Recorded iEEG data were stratified into 11 contiguous, non-overlapping frequency bands and binned into one-minute synchrony features for analysis. Performance of the SVM classifier was assessed using a 5-fold cross validation approach, where preictal training data were taken from 90 minute windows with a 5 minute pre-seizure offset. Analysis of the optimal preictal training time was performed by repeating the cross validation over a range of preictal windows and comparing results. We show that the optimization of feature selection varies for each subject, i.e. algorithms are subject specific, but achieve prediction performance significantly better than a time-matched Poisson random predictor (p<0.05) in 5/5 dogs analyzed. PMID:26241907

  15. Naturally Occurring Variation in Trophoblast Invasion as a Source of Novel (Epigenetic) Biomarkers

    PubMed Central

    van Dijk, Marie; Visser, Allerdien; Posthuma, Janny; Poutsma, Ankie; Oudejans, Cees B. M.

    2012-01-01

    During the first trimester of pregnancy fetal trophoblasts invade the maternal decidua, thereby remodeling the maternal spiral arteries. This process of trophoblast invasion is very similar to cancer cell invasion, with multiple signaling pathways shared between the two. Pregnancy-related diseases, e.g., pre-eclampsia, and cancer metastasis start with a decrease or increase in cellular invasion, respectively. Here, we investigate if first trimester placental explants can be used to identify epigenetic factors associated with changes in cellular invasion and their potential use as biomarkers. We show that the outgrowth potential of first trimester explants significantly correlates with promoter methylation of PRKCDBP and MMP2, two genes known to be differentially methylated in both placenta and cancer. The increase in methylation percentage of placental cells coincides with an increase in invasion potential. Subsequently, as a non-invasive marker must be detectable in blood, plasma samples of pregnant and non-pregnant women were analyzed. The MMP2 promoter showed high methylation levels in non-pregnant plasma samples, which decreased in pregnant plasma samples which also contain placental DNA. The decrease in methylated plasma DNA during pregnancy is most likely due to the fractional increase in unmethylated placental DNA. This suggests that the level of unmethylated DNA has the potential to be used as an invasion marker, where higher levels of unmethylated DNA indicate a lower invasion potential of trophoblasts. These proof of principle data provide evidence that human first trimester placental explants are an excellent ex vivo model system to identify (epigenetic) factors and thus potential biomarkers associated with changes in cellular invasion, e.g., to detect pregnancy-related diseases or cancer metastasis. To identify novel biomarkers the next step is to correlate naturally occurring variation in invasion potential to changes in (epigenetic) factors by genome-wide approaches such as massively parallel sequencing. PMID:22363344

  16. Naturally occurring secondary nutritional hyperparathyroidism in cattle egrets (Bubulcus ibis) from Central Texas

    USGS Publications Warehouse

    Phalen, D.N.; Drew, M.L.; Contreras, C.; Roset, K.; Mora, M.

    2005-01-01

    Naturally occurring secondary nutritional hyperparathyroidism is described in the nestlings of two colonies of cattle egrets (Bubulcus ibis) from Central Texas (Bryan and San Antonio, Texas, USA). Nestlings from a third colony (Waco, Texas, USA) were collected in a subsequent year for comparison. Birds from the first two colonies consistently had severe osteopenia and associated curving deformities and folding fractures of their long bones. These birds also had reduced bone ash, increased osteoclasia, a marked decrease in osteoblast activity, variable lengthening and shortening of the hypertrophic zone of the epiphyseal cartilage, decreased and disorganized formation of new bone, and a marked hypertrophy and hyperplasia of the parathyroid glands as compared to birds collected from the third colony. Fibrous osteodystrophy was found in all of the birds from San Antonio and Bryan. Evidence of moderate to severe calcium deficiency was also identified in 33% of the cattle egrets collected from Waco. Gut contents of affected chicks contained predominately grasshoppers and crickets; vertebrate prey items were absent from the Bryan birds. Grasshoppers and crickets collected from fields frequented by the adult egrets in 1994 had 0.12-0.28% calcium and 0.76-0.81% phosphorus. Pooled grasshoppers and crickets collected during a subsequent wet early spring averaged 0.24% calcium and 0.65% phosphorus. Although the phosphorus content of the insect prey was adequate for growth, calcium was approximately one-third the minimum calcium requirement needed for growth for other species of birds. It was postulated that cattle egrets breeding in Central Texas have expanded their range into habitat that contains less vertebrate prey, and as a result, many nestling egrets are being fed diets that contain suboptimal calcium. Therefore, in years where vertebrate prey is scarce and forage for insect prey is reduced in calcium, nestling egrets are at risk for developing secondary nutritional hyperparathyroidism. ?? Wildlife Disease Association 2005.

  17. Inactivation of naturally occurring microbiota in cucumber juice by pressure treatment.

    PubMed

    Zhao, Liang; Wang, Yongtao; Wang, Siyuan; Li, Hui; Huang, Wenshu; Liao, Xiaojun

    2014-03-17

    The inactivation effects of high hydrostatic pressure (HHP) (350MPa/10min, 400MPa/4min and 500MPa/2min) with homogenization (20MPa/2min), nisin (100IU/mL) and decompression time (<3s and 7-8s) on naturally occurring microbiota in cucumber juice were investigated. Initial concentration of yeasts and molds (Y&M) was 5.6×10(3)-2.4×10(4)CFU/mL, and total plate count (TPC) was 1.0×10(5)-3.5×10(5)CFU/mL. Y&M were inactivated below the detection level (≤10CFU/mL) in all cases. The reduction of TPC in non-homogenized cucumber juice (NHCJ) was 2.5-3.0 log cycles, which was significantly higher than 1.0 log cycle in homogenized cucumber juice. The combination of nisin with HHP had a synergistic effect on the inactivation of TPC. The reduction of TPC in NHCJ with a decompression time of <3s was approximately 4.5 log cycles, which was significantly higher than a decompression time of 7-8s. Five non-linear models including the biphasic, Weibull, modified Gompertz, log-logistic and Baranyi models were fitted to TPC inactivation curves for the NHCJ at 300, 350 and 400MPa for 2-15min and 500MPa for 2-8min at a decompression time of <3s. The biphasic model provided the best fit for the data. PMID:24441021

  18. Forecasting Seizures Using Intracranial EEG Measures and SVM in Naturally Occurring Canine Epilepsy.

    PubMed

    Brinkmann, Benjamin H; Patterson, Edward E; Vite, Charles; Vasoli, Vincent M; Crepeau, Daniel; Stead, Matt; Howbert, J Jeffry; Cherkassky, Vladimir; Wagenaar, Joost B; Litt, Brian; Worrell, Gregory A

    2015-01-01

    Management of drug resistant focal epilepsy would be greatly assisted by a reliable warning system capable of alerting patients prior to seizures to allow the patient to adjust activities or medication. Such a system requires successful identification of a preictal, or seizure-prone state. Identification of preictal states in continuous long- duration intracranial electroencephalographic (iEEG) recordings of dogs with naturally occurring epilepsy was investigated using a support vector machine (SVM) algorithm. The dogs studied were implanted with a 16-channel ambulatory iEEG recording device with average channel reference for a mean (st. dev.) of 380.4 (+87.5) days producing 220.2 (+104.1) days of intracranial EEG recorded at 400 Hz for analysis. The iEEG records had 51.6 (+52.8) seizures identified, of which 35.8 (+30.4) seizures were preceded by more than 4 hours of seizure-free data. Recorded iEEG data were stratified into 11 contiguous, non-overlapping frequency bands and binned into one-minute synchrony features for analysis. Performance of the SVM classifier was assessed using a 5-fold cross validation approach, where preictal training data were taken from 90 minute windows with a 5 minute pre-seizure offset. Analysis of the optimal preictal training time was performed by repeating the cross validation over a range of preictal windows and comparing results. We show that the optimization of feature selection varies for each subject, i.e. algorithms are subject specific, but achieve prediction performance significantly better than a time-matched Poisson random predictor (p<0.05) in 5/5 dogs analyzed. PMID:26241907

  19. Naturally occurring dominant resistance mutations to HCV protease and polymerase inhibitors in treatment-nave patients

    PubMed Central

    Kuntzen, Thomas; Timm, Joerg; Berical, Andrew; Lennon, Niall; Berlin, Aaron M.; Young, Sarah K.; Lee, Bongshin; Heckerman, David; Carlson, Jonathan; Reyor, Laura L.; Kleyman, Marianna; McMahon, Cory M.; Birch, Christopher; Wiesch, Julian Schulze zur; Ledlie, Timothy; Koehrsen, Michael; Kodira, Chinnappa; Roberts, Andrew D.; Lauer, Georg M.; Rosen, Hugo R.; Bihl, Florian; Cerny, Andreas; Spengler, Ulrich; Liu, Zhimin; Kim, Arthur Y.; Xing, Yanming; Schneidewind, Arne; Madey, Margaret A.; Fleckenstein, Jaquelyn F.; Park, Vicki M.; Galagan, James E.; Nusbaum, Chad; Walker, Bruce D.; Lake-Bakaar, Gerond V.; Daar, Eric S.; Jacobson, Ira M.; Gomperts, Edward D.; Edlin, Brian R.; Donfield, Sharyne M.; Chung, Raymond T.; Talal, Andrew H.; Marion, Tony; Birren, Bruce W.; Henn, Matthew R.; Allen, Todd M.

    2008-01-01

    Resistance mutations to HCV NS3 protease inhibitors in <1% of the viral quasispecies may still allow >1000-fold viral load reductions upon treatment, consistent with their reported reduced replicative fitness in vitro. Recently, however, an R155K protease mutation was reported as the dominant quasispecies in a treatment-nave individual, raising concerns about possible full drug resistance. To investigate the prevalence of dominant STAT-C resistance mutations in the population we analyzed HCV genome sequences from 507 treatment-nave HCV genotype 1 infected patients from the US, Germany and Switzerland. Phylogenetic sequence analysis and viral load data were used to identify the possible spread of replication competent, drug resistant viral strains in the population and to infer the consequences of these mutations upon viral replication in vivo. Mutations described to confer resistance to the protease inhibitors Telaprevir, BILN2061, ITMN-191, SCH6 and Boceprevir, the NS5B polymerase inhibitor AG-021541, and to the NS4A antagonist ACH-806 were observed mostly as sporadic, unrelated cases, at frequencies between 0.3% and 2.8% in the population, including two patients with possible multi-drug resistance. Collectively, however, 8.6% of the genotype 1a and 1.4% of the genotype 1b infected patients carried at least one dominant resistance mutation. Viral loads were high in the majority of these patients, suggesting that drug resistant viral strains might achieve replication levels comparable to non-resistant viruses in vivo. Conclusion: Naturally occurring dominant STAT-C resistance mutations are common in HCV genotype 1 infected treatment-nave patients. Their influence on treatment outcome should further be characterized to evaluate possible benefits of drug resistance testing for individual tailoring of drug combinations when treatment options are limited due to previous non-response to peginterferon and ribavirin. PMID:19026009

  20. Efficacy of enrofloxacin in the treatment of naturally occurring acute clinical Escherichia coli mastitis.

    PubMed

    Suojala, L; Simojoki, H; Mustonen, K; Kaartinen, L; Pyörälä, S

    2010-05-01

    The efficacy of the combination of systemic enrofloxacin (5mg/kg twice with a 24-h interval, first dose i.v., second dose s.c.) and the nonsteroidal antiinflammatory agent ketoprofen (3mg/kg i.m. or 4 mg/kg per os daily for 1 to 3 d) treatment was compared with antiinflammatory treatment only in dairy cows with naturally occurring acute clinical Escherichia coli mastitis. A total of 132 cows with acute clinical mastitis and with confirmed growth of E. coli in a pretreatment milk sample were randomly allocated to 1 of 2 treatment groups. Response to treatment was evaluated clinically and by bacteriological culturing and determination of N-acetyl-beta-d-glucosaminidase (NAGase) activity on d 2 and 21 posttreatment. Enrofloxacin treatment did not increase bacteriological (90.5% of treated vs. 86.8% of nontreated cured) or clinical cure (46.7% of treated vs. 57.1% of nontreated cured), cow survival (95.3% of treated vs. 92.7% of nontreated), or quarter milk production assessed 21 d posttreatment (21.8 vs. 29.3% return to preinfection level for nontreated cows), nor did it decrease mammary gland tissue damage estimated using determination of milk NAGase activity (24.0+/-0.3 vs. 18.3+/-1.3 pmol of 4-methylumbelliferone per min per microL for nontreated cows). Treatment did not influence the number of study cows remaining in the herd after 6 mo (71.9% of treated vs. 80.6% of nontreated). The only significant effects of enrofloxacin were enhancing the bacteriological cure (odds ratio=3.32 for treated cows) and decreasing the clinical cure (odds ratio=0.05 for treated cows) on d 2 posttreatment. Our results did not support the use of enrofloxacin to treat acute clinical E. coli mastitis. PMID:20412909

  1. Studying human respiratory disease in animals - role of induced and naturally occurring models.

    PubMed

    Williams, Kurt; Roman, Jesse

    2016-01-01

    Respiratory disorders like asthma, emphysema, and pulmonary fibrosis affect millions of Americans and many more worldwide. Despite advancements in medical research that have led to improved understanding of the pathophysiology of these conditions and sometimes to new therapeutic interventions, these disorders are for the most part chronic and progressive; current interventions are not curative and do not halt disease progression. A major obstacle to further advancements relates to the absence of animal models that exactly resemble the human condition, which delays the elucidation of relevant mechanisms of action, the unveiling of biomarkers of disease progression, and identification of new targets for intervention in patients. There are currently many induced animal models of human respiratory disease available for study, and even though they mimic features of human disease, discoveries in these models have not always translated into safe and effective treatments in humans. A major obstacle relates to the genetic, anatomical, and functional variations amongst species, which represents the major challenge to overcome when searching for appropriate models of respiratory disease. Nevertheless, rodents, in particular mice, have become the most common species used for experimentation, due to their relatively low cost, size, and adequate understanding of murine genetics, among other advantages. Less well known is the fact that domestic animals also suffer from respiratory illnesses similar to those found in humans. Asthma, bronchitis, pneumonia, and pulmonary fibrosis are among the many disorders occurring naturally in dogs, cats, and horses, among other species. These models might better resemble the human condition and are emphasized here, but further investigations are needed to determine their relevance. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. PMID:26467890

  2. Acute Toxicological Responses of Fischer Rats to Naturally Occurring Asbestos from theUnited States and Canada

    EPA Science Inventory

    This study was designed to provide understanding of the toxicity of naturally occurring asbestos (NOA) including Libby amphibole (LA), Sumas Mountain chrysotile (SM), EI Dorado Hills tremolite (ED) and Ontario actinolite/ferroactinolite cleavage fragments (ON). Ratrespirable fra...

  3. Naturally occurring heavy radioactive elements in the geothermal microcosm of the Los Azufres (Mexico) volcanic complex.

    PubMed

    Abuhani, W A; Dasgupta-Schubert, N; Villaseñor, L M; García Avila, D; Suárez, L; Johnston, C; Borjas, S E; Alexander, S A; Landsberger, S; Suárez, M C

    2015-01-01

    The Los Azufres geothermal complex of central Mexico is characterized by fumaroles and boiling hot-springs. The fumaroles form habitats for extremophilic mosses and ferns. Physico-chemical measurements of two relatively pristine fumarolic microcosms point to their resemblance with the paleo-environment of earth during the Ordovician and Devonian periods. These geothermal habitats were analysed for the distribution of elemental mass fractions in the rhizospheric soil (RS), the native volcanic substrate (VS) and the sediments (S), using the new high-sensitivity technique of polarized x-ray energy dispersive fluorescence spectrometry (PEDXRF) as well as instrumental neutron activation analysis (INAA) for selected elements. This work presents the results for the naturally occurring heavy radioactive elements (NOHRE) Bi, Th and U but principally the latter two. For the RS, the density was found to be the least and the total organic matter content the most. Bi was found to be negligibly present in all substrate types. The average Th and U mass fractions in the RS were higher than in the VS and about equal to their average mass fractions in the S. The VS mass fraction of Th was higher, and of U lower, than the mass fractions in the earth's crust. In fact for the fumaroles of one site, the average RS mass fractions of these elements were higher than the averaged values for S (without considering the statistical dispersion). The immobilization of the NOHRE in the RS is brought about by the bio-geochemical processes specific to these extremophiles. Its effectiveness is such that despite the small masses of these plants, it compares with, or may sometimes exceed, the immobilization of the NOHRE in the S by the abiotic and aggressive chemical action of the hot-springs. These results indicate that the fumarolic plants are able to transform the volcanic substrate to soil and to affect the NOHRE mass fractions even though these elements are not plant nutrients. Mirrored back to the paleo times when such plant types were ubiquitous, it would mean that the first plants contributed significantly to pedogenesis and the biogeochemical recycling of even the heaviest and radioactive elements. Such plants may potentially be useful for the phytostabilisation of soil moderately contaminated by the NOHRE. Furthermore where applicable, geochronology may require taking into account the influence of the early plants on the NOHRE distributions. PMID:25464039

  4. Neovastat, a naturally occurring multifunctional antiangiogenic drug, in phase III clinical trials.

    PubMed

    Falardeau, P; Champagne, P; Poyet, P; Hariton, C; Dupont, E

    2001-12-01

    Recent studies have indicated that bone marrow angiogenesis is increased in multiple myeloma, suggesting that treatment with an antiangiogenic agent might be useful. Among the new antiangiogenic drugs in development, Neovastat (AE-941; Aeterna Laboratories, Quebec City, Canada) can be classified as a naturally occurring multifunctional antiangiogenic agent. It has a marked inhibitory effect on the formation of blood vessels in the chicken embryo vascularization assay (EVT) and endothelial cell proliferation. Furthermore, in vivo experiments showed that oral administration of Neovastat blocks the formation of blood vessels in Matrigel implants containing basic fibroblast growth factor (bFGF). The antiangiogenic activity of Neovastat was found to be associated with two mechanisms of action. In addition to the inhibition of the matrix metalloproteinase activities (MMP-2, MMP-9, and MMP-12), Neovastat inhibits vascular endothelial growth factor (VEGF) binding to endothelial cells, VEGF-dependent tyrosine phosphorylation, and VEGF-induced vascular permeability in mice. Neovastat was also found to have a significant antitumor activity. Oral administration of Neovastat in mice with subcutaneous grafted breast cancer (DA3) cells showed a significant reduction in tumor volume. Neovastat also decreased the number of lung metastases in the Lewis lung carcinoma model. Interestingly, the effect of Neovastat was additive to cisplatin in this model. Furthermore, no treatment-related mortality or loss of body weight was observed. Also, toxicology studies in rats and monkeys demonstrate no dose-limiting toxicity or target organ damage after 1 year of chronic exposure, thus suggesting that Neovastat could be safely administered in humans. Four clinical studies have been conducted to establish the dosing, safety, and early efficacy of Neovastat administered orally. In the oncology field, 482 patients have received Neovastat, of which 146 with solid tumors were exposed to the drug for more than 6 months. Two phase III clinical trials are currently underway. A phase III double-blind placebo-controlled study is being conducted to evaluate the efficacy of Neovastat in addition to induction chemotherapy/radiotherapy combined modality treatment in patients with unresectable non-small cell lung cancer stage IIIA and IIIB. A second phase III randomized, double-blind placebo-controlled study evaluates the efficacy of Neovastat as a monotherapy in metastatic renal cell carcinoma patients who have progressed following a first-line immunotherapy. Neovastat efficacy is also being evaluated in a registration phase II trial in patients with early relapse or refractory multiple myeloma. PMID:11740820

  5. Manufactured Home Testing in Simulated and Naturally Occurring High Winds for WCTE Conference

    SciTech Connect

    William D. Richins; Thomas K. Larson; Jeffrey M. Lacy; Ryan G. Kobbe

    2006-08-01

    A typical double-wide manufactured home was tested in simulated and naturally occurring high winds to understand structural behavior and improve performance during severe windstorms. Seven (7) lateral load tests were conducted on a double-wide manufactured home at a remote field test site in Wyoming. An extensive instrumentation package monitored the overall behavior of the home and collected data vital to validating computational software for the manufactured housing industry. The tests were designed to approach the design load of the home without causing structural damage, thus allowing the behavior of the home to be accessed when the home was later exposed to high winds (to 80-mph). The data generally show near-linear initial system response with significant non-linear behavior as the applied loads increase. Load transfer across the marriage line is primarily compression. Racking, while present, is very small. Interface slip and shear displacement along the marriage line are nearly insignificant. Horizontal global displacements reached 0.6 inch. These tests were designed primarily to collect data necessary to calibrate a desktop analysis and design software tool, MHTool, under development at the Idaho National Laboratory specifically for manufactured housing. Currently available analysis tools are, for the most part, based on methods developed for "stick built" structures and are inappropriate for manufactured homes. The special materials utilized in manufactured homes, such as rigid adhesives used in the connection of the sheathing materials to the studs, significantly alter the behavior of manufactured homes under lateral loads. Previous full scale tests of laterally loaded manufactured homes confirm the contention that conventional analysis methods are not applicable. System behavior dominates the structural action of manufactured homes and its prediction requires a three dimensional analysis of the complete unit, including tie-downs. This project was sponsored by the US Department of Energy, US Department of Housing and Urban Development, and the Manufactured Housing Institute. The results of this research can lead to savings in annual losses of life and property by providing validated information to enable the advancement of code requirements and by developing engineering software that can predict and optimize wind resistance.

  6. The effect of colloid formulation on colloid osmotic pressure in horses with naturally occurring gastrointestinal disease

    PubMed Central

    2014-01-01

    Background Naturally occurring gastrointestinal disease is an important cause of acute hypoproteinemia in adult horses and hydroxyethyl starch colloid fluid treatment is a component of supportive care in these cases to improve plasma volume and maintain colloid osmotic pressure (COP). The objectives of the present study were to compare 2 formulations of high molecular weight hydroxyethyl starch and their relative effect on COP, acid-base status, and survival of horses with acute hypoproteinemia secondary to gastrointestinal disease. Methods Twenty adult horses, ? 1 year of age, were prospectively enrolled, with informed client consent, if they developed acute hypoproteinemia, defined as a plasma total protein <5.0 g/dL or albumin <2.2 g/dL during hospitalization while undergoing treatment for gastrointestinal disease. Horses were randomly assigned to receive a rapid infusion of either 6% hydroxyethyl starch in 0.9% saline or 6% hydroxyethyl starch in lactated ringers solution at a dose of 10ml/kg. Venous blood gas analysis, COP, and PCV were evaluated before and after colloid administration. Results For both groups, average COP prior to treatment was 11.0 mmHg (9.7 12.2 mmHg) and post colloid treatment was 13.2 mmHg (12.0 -14.7 mmHg) [Normal range 18 22 mmHg]. COP was significantly increased with colloid treatment (p<0.001) but this increase was not significantly different between treatment groups. Venous pH did not change significantly with treatment. Twelve horses survived to hospital discharge and survival did not differ significantly between treatment groups. Conclusions Post-treatment COP improved approximately 20% regardless of the formulation used, however, values did not reach the normal range of COP observed in healthy horses. Acid-base parameters were not significantly impacted by either treatment. Further study is needed to determine how these two products compare with regards to other outcome measures. Evaluation of the relative effects of colloid formulation in horses with clinical disease is a future area of interest. PMID:25237987

  7. Naturally occurring differences in CENH3 affect chromosome segregation in zygotic mitosis of hybrids.

    PubMed

    Maheshwari, Shamoni; Tan, Ek Han; West, Allan; Franklin, F Chris H; Comai, Luca; Chan, Simon W L

    2015-01-01

    The point of attachment of spindle microtubules to metaphase chromosomes is known as the centromere. Plant and animal centromeres are epigenetically specified by a centromere-specific variant of Histone H3, CENH3 (a.k.a. CENP-A). Unlike canonical histones that are invariant, CENH3 proteins are accumulating substitutions at an accelerated rate. This diversification of CENH3 is a conundrum since its role as the key determinant of centromere identity remains a constant across species. Here, we ask whether naturally occurring divergence in CENH3 has functional consequences. We performed functional complementation assays on cenh3-1, a null mutation in Arabidopsis thaliana, using untagged CENH3s from increasingly distant relatives. Contrary to previous results using GFP-tagged CENH3, we find that the essential functions of CENH3 are conserved across a broad evolutionary landscape. CENH3 from a species as distant as the monocot Zea mays can functionally replace A. thaliana CENH3. Plants expressing variant CENH3s that are fertile when selfed show dramatic segregation errors when crossed to a wild-type individual. The progeny of this cross include hybrid diploids, aneuploids with novel genetic rearrangements and haploids that inherit only the genome of the wild-type parent. Importantly, it is always chromosomes from the plant expressing the divergent CENH3 that missegregate. Using chimeras, we show that it is divergence in the fast-evolving N-terminal tail of CENH3 that is causing segregation errors and genome elimination. Furthermore, we analyzed N-terminal tail sequences from plant CENH3s and discovered a modular pattern of sequence conservation. From this we hypothesize that while the essential functions of CENH3 are largely conserved, the N-terminal tail is evolving to adapt to lineage-specific centromeric constraints. Our results demonstrate that this lineage-specific evolution of CENH3 causes inviability and sterility of progeny in crosses, at the same time producing karyotypic variation. Thus, CENH3 evolution can contribute to postzygotic reproductive barriers. PMID:25622028

  8. Naturally Occurring Differences in CENH3 Affect Chromosome Segregation in Zygotic Mitosis of Hybrids

    PubMed Central

    Maheshwari, Shamoni; Tan, Ek Han; West, Allan; Franklin, F. Chris H.; Comai, Luca

    2015-01-01

    The point of attachment of spindle microtubules to metaphase chromosomes is known as the centromere. Plant and animal centromeres are epigenetically specified by a centromere-specific variant of Histone H3, CENH3 (a.k.a. CENP-A). Unlike canonical histones that are invariant, CENH3 proteins are accumulating substitutions at an accelerated rate. This diversification of CENH3 is a conundrum since its role as the key determinant of centromere identity remains a constant across species. Here, we ask whether naturally occurring divergence in CENH3 has functional consequences. We performed functional complementation assays on cenh3-1, a null mutation in Arabidopsis thaliana, using untagged CENH3s from increasingly distant relatives. Contrary to previous results using GFP-tagged CENH3, we find that the essential functions of CENH3 are conserved across a broad evolutionary landscape. CENH3 from a species as distant as the monocot Zea mays can functionally replace A. thaliana CENH3. Plants expressing variant CENH3s that are fertile when selfed show dramatic segregation errors when crossed to a wild-type individual. The progeny of this cross include hybrid diploids, aneuploids with novel genetic rearrangements and haploids that inherit only the genome of the wild-type parent. Importantly, it is always chromosomes from the plant expressing the divergent CENH3 that missegregate. Using chimeras, we show that it is divergence in the fast-evolving N-terminal tail of CENH3 that is causing segregation errors and genome elimination. Furthermore, we analyzed N-terminal tail sequences from plant CENH3s and discovered a modular pattern of sequence conservation. From this we hypothesize that while the essential functions of CENH3 are largely conserved, the N-terminal tail is evolving to adapt to lineage-specific centromeric constraints. Our results demonstrate that this lineage-specific evolution of CENH3 causes inviability and sterility of progeny in crosses, at the same time producing karyotypic variation. Thus, CENH3 evolution can contribute to postzygotic reproductive barriers. PMID:25622028

  9. Increased carbon uptake in marine sediment enabled by naturally occurring electrical conductors

    NASA Astrophysics Data System (ADS)

    Nielsen, M. E.; Cahoon, D. P.; Girguis, P. R.

    2011-12-01

    Reduction-oxidation (redox) gradients are common across marine sediment-water interfaces and result from microbially-mediated reactions such as the oxidation of organic matter coupled to reduction of electron acceptors. Most microbes living in sediments do not have direct access to oxygen in their immediate environment, however it has recently been shown that sulfide-oxidizing microbes may employ extracellular electron transfer (EET) to couple the oxidation of sulfide in the anoxic zone to reduction of oxygen at the sediment-water interface located several centimeters away. However, no mechanisms for this observed phenomenon have been validated. Accordingly, we tested the hypothesis that conductive minerals in marine sediment (specifically pyrite) can couple spatially separated redox reactions such as anaerobic respiration and oxygen reduction. Marine sediment was amended with naturally occurring pyrite in varying concentrations (0, 2, 10 and 50 weight-percent) and then incubated with 10 ?M 13C-labeled acetate. After six hours, the treatments with the greatest amount of added pyrite showed the greatest incorporation of acetate from the labeled pool. The fraction of labeled acetate incorporation more than doubled in the 10 and 50 weight-percent treatments compared to the control sediment. We also designed a circuit to investigate the electrical conductivity of the sediment treatments as a function of added pyrite. A potentiostat was used to establish a known voltage across a sediment column and current was measured. Resistance (the inverse of conductance) was calculated from a linear fit of current data over a range of voltages ranging from 0.5 to 1.0 V. The treatments with added pyrite had lower resistance than background sediment, with the lowest resistance corresponding to the 50% pyrite treatment. We also examined the effect of varying pyrite content on microbial community composition using massively parallel 16S rRNA sequencing. Microbial community analyses reveal that the majority of microbes in the sediment belong to the deltaproteobacteria or gammaproteobacteria classes, which have been previously implicated in EET in laboratory and field-based bioelectrochemical studies. These data force us to reconsider the role of EET and conductive minerals in organic carbon cycling -particularly in metaliferous sediments- and suggest that EET-enabled anaerobic metabolism may represent a significant contribution to marine carbon cycling.

  10. Novel psbA1 Gene from a Naturally Occurring Atrazine-Resistant Cyanobacterial Isolate

    PubMed Central

    Sajjaphan, Kannika; Shapir, Nir; Judd, Adam K.; Wackett, Lawrence P.; Sadowsky, Michael J.

    2002-01-01

    A naturally occurring atrazine-resistant cyanobacterial isolate, strain SG2, was isolated from an atrazine-containing wastewater treatment system at the Syngenta atrazine production facility in St. Gabriel, La. Strain SG2 was resistant to 1,000 ?g of atrazine per ml but showed relatively low resistance to diuron [3-(3,4-dichlorophenyl)-1,1-dimethyl urea]. Analyses of 16S ribosomal DNA indicated that strain SG2 falls into the Synechocystis/Pleurocapsa/Microcystis group. Photosynthetically driven oxygen evolution in strain SG2 was only slightly inhibited (about 10%) by 2,000 ?g of atrazine per ml, whereas in the control strain Synechocystis 6803, oxygen evolution was inhibited 90% by 1,000 ?g of atrazine per ml. No atrazine accretion, mineralization, or metabolites were detected when strain SG2 was grown with [14C]atrazine. Strain SG2 contained three copies of the psbA gene, which encodes the D1 protein of the photosystem II reaction center. Nucleotide sequence analyses indicated that the psbA2 and psbA3 genes encoded predicted proteins with the same amino acid sequence. However, the psbA1 gene product contained five extra amino acids, which were not found in PsbA proteins from five other cyanobacteria. Moreover, the PsbA1 protein from strain SG2 had an additional 13 amino acid changes compared to the PsbA2/PsbA3 proteins and contained 10 amino acid alterations compared to conserved residues found in other cyanobacteria. Reverse transcriptase PCR analysis indicated that the psbA1 gene and the psbA2/psbA3 gene(s) were expressed in photosynthetically grown cells in the presence of atrazine. These results suggest that strong selection pressure conferred by the continual input of atrazine has contributed to the evolution of a herbicide-resistant, yet photosynthetically efficient, psbA gene in a cyanobacterium. PMID:11872488

  11. Contribution of Schwann Cells to Remyelination in a Naturally Occurring Canine Model of CNS Neuroinflammation

    PubMed Central

    Imbschweiler, Ilka; Wewetzer, Konstantin; Baumgärtner, Wolfgang; Seehusen, Frauke

    2015-01-01

    Gliogenesis under pathophysiological conditions is of particular clinical relevance since it may provide evidence for regeneration promoting cells recruitable for therapeutic purposes. There is evidence that neurotrophin receptor p75 (p75NTR)-expressing cells emerge in the lesioned CNS. However, the phenotype and identity of these cells, and signals triggering their in situ generation under normal conditions and certain pathological situations has remained enigmatic. In the present study, we used a spontaneous, idiopathic and inflammatory CNS condition in dogs with prominent lympho-histiocytic infiltration as a model to study the phenotype of Schwann cells and their relation to Schwann cell remyelination within the CNS. Furthermore, the phenotype of p75NTR-expressing cells within the injured CNS was compared to their counter-part in control sciatic nerve and after peripheral nerve injury. In addition, organotypic slice cultures were used to further elucidate the origin of p75NTR-positive cells. In cerebral and cerebellar white and grey matter lesions as well as in the brain stem, p75NTR-positive cells co-expressed the transcription factor Sox2, but not GAP-43, GFAP, Egr2/Krox20, periaxin and PDGFR-α. Interestingly, and contrary to the findings in control sciatic nerves, p75NTR-expressing cells only co-localized with Sox2 in degenerative neuropathy, thus suggesting that such cells might represent dedifferentiated Schwann cells both in the injured CNS and PNS. Moreover, effective Schwann cell remyelination represented by periaxin- and P0-positive mature myelinating Schwann cells, was strikingly associated with the presence of p75NTR/Sox2-expressing Schwann cells. Intriguingly, the emergence of dedifferentiated Schwann cells was not affected by astrocytes, and a macrophage-dominated inflammatory response provided an adequate environment for Schwann cells plasticity within the injured CNS. Furthermore, axonal damage was reduced in brain stem areas with p75NTR/Sox2-positive cells. This study provides novel insights into the involvement of Schwann cells in CNS remyelination under natural occurring CNS inflammation. Targeting p75NTR/Sox2-expressing Schwann cells to enhance their differentiation into competent remyelinating cells appears to be a promising therapeutic approach for inflammatory/demyelinating CNS diseases. PMID:26196511

  12. A Naturally Occurring Canine Model of Autosomal Recessive Congenital Stationary Night Blindness

    PubMed Central

    Kondo, Mineo; Das, Gautami; Imai, Ryoetsu; Santana, Evelyn; Nakashita, Tomio; Imawaka, Miho; Ueda, Kosuke; Ohtsuka, Hirohiko; Sakai, Kazuhiko; Aihara, Takehiro; Kato, Kumiko; Sugimoto, Masahiko; Ueno, Shinji; Nishizawa, Yuji; Aguirre, Gustavo D.; Miyadera, Keiko

    2015-01-01

    Congenital stationary night blindness (CSNB) is a non-progressive, clinically and genetically heterogeneous disease of impaired night vision. We report a naturally-occurring, stationary, autosomal recessive phenotype in beagle dogs with normal daylight vision but absent night vision. Affected dogs had normal retinas on clinical examination, but showed no detectable rod responses. They had “negative-type” mixed rod and cone responses in full-field ERGs. Their photopic long-flash ERGs had normal OFF-responses associated with severely reduced ON-responses. The phenotype is similar to the Schubert-Bornschein form of complete CSNB in humans. Homozygosity mapping ruled out most known CSNB candidates as well as CACNA2D4 and GNB3. Three remaining genes were excluded based on sequencing the open reading frame and intron-exon boundaries (RHO, NYX), causal to a different form of CSNB (RHO) or X-chromosome (NYX, CACNA1F) location. Among the genes expressed in the photoreceptors and their synaptic terminals, and mGluR6 cascade and modulators, reduced expression of GNAT1, CACNA2D4 and NYX was observed by qRT-PCR in both carrier (n = 2) and affected (n = 2) retinas whereas CACNA1F was down-regulated only in the affecteds. Retinal morphology revealed normal cellular layers and structure, and electron microscopy showed normal rod spherules and synaptic ribbons. No difference from normal was observed by immunohistochemistry (IHC) for antibodies labeling rods, cones and their presynaptic terminals. None of the retinas showed any sign of stress. Selected proteins of mGluR6 cascade and its modulators were examined by IHC and showed that PKCα weakly labeled the rod bipolar somata in the affected, but intensely labeled axonal terminals that appeared thickened and irregular. Dendritic terminals of ON-bipolar cells showed increased Goα labeling. Both PKCα and Goα labeled the more prominent bipolar dendrites that extended into the OPL in affected but not normal retinas. Interestingly, RGS11 showed no labeling in the affected retina. Our results indicate involvement of a yet unknown gene in this canine model of complete CSNB. PMID:26368928

  13. The stretch-shortening cycle : a model to study naturally occurring neuromuscular fatigue.

    PubMed

    Nicol, Caroline; Avela, Janne; Komi, Paavo V

    2006-01-01

    Neuromuscular fatigue has traditionally been examined using isolated forms of either isometric, concentric or eccentric actions. However, none of these actions are naturally occurring in human (or animal) ground locomotion. The basic muscle function is defined as the stretch-shortening cycle (SSC), where the preactivated muscle is first stretched (eccentric action) and then followed by the shortening (concentric) action. As the SSC taxes the skeletal muscles very strongly mechanically, its influence on the reflex activation becomes apparent and very different from the isolated forms of muscle actions mentioned above. The ground contact phases of running, jumping and hopping etc. are examples of the SSC for leg extensor muscles; similar phases can also be found for the upper-body activities. Consequently, it is normal and expected that the fatigue phenomena should be explored during SSC activities. The fatigue responses of repeated SSC actions are very versatile and complex because the fatigue does not depend only on the metabolic loading, which is reportedly different among muscle actions. The complexity of SSC fatigue is well reflected by the recovery patterns of many neuromechanical parameters. The basic pattern of SSC fatigue response (e.g. when using the complete exhaustion model of hopping or jumping) is the bimodality showing an immediate reduction in performance during exercise, quick recovery within 1-2 hours, followed by a secondary reduction, which may often show the lowest values on the second day post-exercise when the symptoms of muscle soreness/damage are also greatest. The full recovery may take 4-8 days depending on the parameter and on the severity of exercise. Each subject may have their own time-dependent bimodality curve. Based on the reviewed literature, it is recommended that the fatigue protocol is 'completely' exhaustive to reduce the important influence of inter-subject variability in the fatigue responses. The bimodality concept is especially apparent for stretch reflex responses, measured either in passive or active conditions. Interestingly, the reflex responses follow parallel changes with some of the pure mechanical parameters, such as yielding of the braking force during an initial ground contact of running or hopping. The mechanism of SSC fatigue and especially the bimodal response of performance deterioration and its recovery are often difficult to explain. The immediate post-exercise reduction in most of the measured parameters and their partial recovery 1-2 hours post-exercise can be explained primarily to be due to metabolic fatigue induced by exercise. The secondary reduction in these parameters takes place when the muscle soreness is highest. The literature gives several suggestions including the possible structural damage of not only the extrafusal muscle fibres, but also the intrafusal ones. Temporary changes in structural proteins and muscle-tendon interaction may be related to the fatigue-induced force reduction. Neural adjustments in the supraspinal level could naturally be operative, although many studies quoted in this article emphasise more the influences of exhaustive SSC fatigue on the fusimotor-muscle spindle system. It is, however, still puzzling why the functional recovery lasts several days after the disappearance of muscle soreness. Unfortunately, this and many other possible mechanisms need more thorough testing in animal models provided that the SSC actions can be truly performed as they appear in normal human locomotion. PMID:17052133

  14. A Naturally Occurring Domestic Cat APOBEC3 Variant Confers Resistance to Feline Immunodeficiency Virus Infection

    PubMed Central

    Yoshikawa, Rokusuke; Izumi, Taisuke; Yamada, Eri; Nakano, Yusuke; Misawa, Naoko; Ren, Fengrong; Carpenter, Michael A.; Ikeda, Terumasa; Münk, Carsten; Harris, Reuben S.; Miyazawa, Takayuki; Koyanagi, Yoshio

    2015-01-01

    ABSTRACT Apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like 3 (APOBEC3; A3) DNA cytosine deaminases can be incorporated into progeny virions and inhibit lentiviral replication. On the other hand, viral infectivity factor (Vif) of lentiviruses antagonizes A3-mediated antiviral activities by degrading A3 proteins. It is known that domestic cat (Felis catus) APOBEC3Z3 (A3Z3), the ortholog of human APOBEC3H, potently suppresses the infectivity of vif-defective feline immunodeficiency virus (FIV). Although a recent report has shown that domestic cat encodes 7 haplotypes (hap I to hap VII) of A3Z3, the relevance of A3Z3 polymorphism in domestic cats with FIV Vif has not yet been addressed. In this study, we demonstrated that these feline A3Z3 variants suppress vif-defective FIV infectivity. We also revealed that codon 65 of feline A3Z3 is a positively selected site and that A3Z3 hap V is subject to positive selection during evolution. It is particularly noteworthy that feline A3Z3 hap V is resistant to FIV Vif-mediated degradation and still inhibits vif-proficient viral infection. Moreover, the side chain size, but not the hydrophobicity, of the amino acid at position 65 determines the resistance to FIV Vif-mediated degradation. Furthermore, phylogenetic analyses have led to the inference that feline A3Z3 hap V emerged approximately 60,000 years ago. Taken together, these findings suggest that feline A3Z3 hap V may have been selected for escape from an ancestral FIV. This is the first evidence for an evolutionary “arms race” between the domestic cat and its cognate lentivirus. IMPORTANCE Gene diversity and selective pressure are intriguing topics in the field of evolutionary biology. A direct interaction between a cellular protein and a viral protein can precipitate an evolutionary arms race between host and virus. One example is primate APOBEC3G, which potently restricts the replication of primate lentiviruses (e.g., human immunodeficiency virus type 1 [HIV-1] and simian immunodeficiency virus [SIV]) if its activity is not counteracted by the viral Vif protein. Here we investigate the ability of 7 naturally occurring variants of feline APOBEC3, APOBEC3Z3 (A3Z3), to inhibit FIV replication. Interestingly, one feline A3Z3 variant is dominant, restrictive, and naturally resistant to FIV Vif-mediated degradation. Phylogenetic analyses revealed that the ancestral change that generated this variant could have been caused by positive Darwinian selection, presumably due to an ancestral FIV infection. The experimental-phylogenetic investigation sheds light on the evolutionary history of the domestic cat, which was likely influenced by lentiviral infection. PMID:26491161

  15. Quantifying intracellular metabolites in yeast using a matrix with minimal interference from naturally occurring analytes.

    PubMed

    Magdenoska, Olivera; Knudsen, Peter Boldsen; Svenssen, Daniel Killerup; Nielsen, Kristian Fog

    2015-10-15

    For quantification of intracellular metabolites, mass spectrometry combined with liquid chromatography, capillary electrophoresis, or gas chromatography is currently the method of choice, especially when combined with stable isotope-labeled internal standards (SIL-ISs). Due to the difficulties in finding a biological matrix free of intracellular metabolites, a standard addition based validation is needed. Here, we present an alternative by producing a matrix with minimal signal interferences on both the analytes and their SIL-ISs. The matrix was obtained by cultivating Saccharomyces cerevisiae in [(13)C6]glucose/nonlabeled glucose (50:50, w/w) growth medium. The areas of both (12)C6 and (13)C6 fractions of ATP in the matrix were measured to be 2% of the sum of the areas of all ATP isotopes detected. The matrix allowed for spiking of both the nonlabeled and SIL-ISs and more straightforward validation. The intra- and inter-day accuracy and precision were ?80% and ?20%, respectively. The methodology was used for quantification of nucleotides, coenzymes, and redox compounds from Saccharomyces cerevisiae. The determined energy charge ratio was 0.9, whereas the Mal-CoA/Ac-CoA ratio was 0.04. The analysis of the redox compounds was challenging due to the oxidation of NADH and NADPH, when dissolved in water or tributylamine. The oxidation was reduced by dissolving them in ammonium acetate solution (pH 8.0). PMID:26142219

  16. Mortality of one-week-old chickens during naturally occurring Marek's disease virus infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mareks disease (MD) is a serious economic disease of chickens which occurs worldwide. MD can present as one of several forms, with the most commonly occurring forms being the lymphoproliferative diseases. Under experimental conditions, an early mortality syndrome has been recognized following infec...

  17. Investigation of Naturally Occurring Radio Nuclides in Shir-kuh Granites

    SciTech Connect

    Mazarei, Mohammad Mehdi; Zarei, Mojtaba

    2011-12-26

    One of the principle natural radiation resources is Granite which can be dangerous for human because of its radiations. Based on this fact, in this research we attempt to specify the activity amount of these natural radio nuclides, existing in Shir-kuh Granite of Yazd state. To specify the activity amount of this natural radio nuclides, it has been applied the measurement method of Gamma spectroscopy using high purity Germanium (HPGe) detector.

  18. Understanding the Radioactive Ingrowth and Decay of Naturally Occurring Radioactive Materials in the Environment: An Analysis of Produced Fluids from the Marcellus Shale

    PubMed Central

    Nelson, Andrew W.; Eitrheim, Eric S.; Knight, Andrew W.; May, Dustin; Mehrhoff, Marinea A.; Shannon, Robert; Litman, Robert; Burnett, William C.; Forbes, Tori Z.

    2015-01-01

    Background The economic value of unconventional natural gas resources has stimulated rapid globalization of horizontal drilling and hydraulic fracturing. However, natural radioactivity found in the large volumes of “produced fluids” generated by these technologies is emerging as an international environmental health concern. Current assessments of the radioactivity concentration in liquid wastes focus on a single element—radium. However, the use of radium alone to predict radioactivity concentrations can greatly underestimate total levels. Objective We investigated the contribution to radioactivity concentrations from naturally occurring radioactive materials (NORM), including uranium, thorium, actinium, radium, lead, bismuth, and polonium isotopes, to the total radioactivity of hydraulic fracturing wastes. Methods For this study we used established methods and developed new methods designed to quantitate NORM of public health concern that may be enriched in complex brines from hydraulic fracturing wastes. Specifically, we examined the use of high-purity germanium gamma spectrometry and isotope dilution alpha spectrometry to quantitate NORM. Results We observed that radium decay products were initially absent from produced fluids due to differences in solubility. However, in systems closed to the release of gaseous radon, our model predicted that decay products will begin to ingrow immediately and (under these closed-system conditions) can contribute to an increase in the total radioactivity for more than 100 years. Conclusions Accurate predictions of radioactivity concentrations are critical for estimating doses to potentially exposed individuals and the surrounding environment. These predictions must include an understanding of the geochemistry, decay properties, and ingrowth kinetics of radium and its decay product radionuclides. Citation Nelson AW, Eitrheim ES, Knight AW, May D, Mehrhoff MA, Shannon R, Litman R, Burnett WC, Forbes TZ, Schultz MK. 2015. Understanding the radioactive ingrowth and decay of naturally occurring radioactive materials in the environment: an analysis of produced fluids from the Marcellus Shale. Environ Health Perspect 123:689–696; http://dx.doi.org/10.1289/ehp.1408855 PMID:25831257

  19. Stable isotopes of nitrate reflect natural attenuation of propellant residues on military training ranges.

    PubMed

    Bordeleau, Genevive; Savard, Martine M; Martel, Richard; Smirnoff, Anna; Ampleman, Guy; Thiboutot, Sonia

    2013-08-01

    Nitroglycerin (NG) and nitrocellulose (NC) are constituents of double-base propellants used notably for firing antitank ammunitions. Nitroglycerin was detected in soil and water samples from the unsaturated zone (pore water) at an active antitank firing position, where the presence of high nitrate (NO3(-)) concentrations suggests that natural attenuation of NG is occurring. However, concentrations alone cannot assess if NG is the source of NO3(-), nor can they determine which degradation processes are involved. To address this issue, isotopic ratios (?(15)N, ?(18)O) were measured for NO3(-) produced from NG and NC through various controlled degradation processes and compared with ratios measured in field pore water samples. Results indicate that propellant combustion and degradation mediated by soil organic carbon produced the observed NO3(-) in pore water at this site. Moreover, isotopic results are presented for NO3(-) produced through photolysis of propellant constituents, which could be a dominant process at other sites. The isotopic data presented here constitute novel information regarding a source of NO3(-) that was practically not documented before and a basis to study the contamination by energetic materials in different contexts. PMID:23815525

  20. Football Injuries Occurring on Natural Grass and Tartan Turf. A Comparison Study Covering 17 Years at the University of Wisconsin.

    ERIC Educational Resources Information Center

    Keene, J. S.; And Others

    A longitudinal study of university football players who played on Tartan Turf and/or natural grass was conducted to determine the types and severity of injuries occuring on the different field surfaces. Overall injury rates on Tartan Turf were found to be significantly lower than those sustained on natural grass. (JD)

  1. AcuteToxicological Responses of Fischer Rats to Naturally Occurring Asbestos Samples from the United States and Canada

    EPA Science Inventory

    The potential public health issues related to exposure to natural asbestos deposits (commonly termed naturally occurring asbestos, NO A) has gained the regulatory and media spotlight in recent years. Arguably the most well known example is Libby, Montana, the site of the largest ...

  2. Naturally-Occurring Radionuclides In Drinking Water From Surface And Groundwater Reservoirs

    NASA Astrophysics Data System (ADS)

    Carvalho, F. P.; Madruga, M. J.; Oliveira, J. M.; Lopes, I.; Ferrador, G.; Sequeira, M. M.

    2008-08-01

    Radioactivity in water for human consumption is under closer scrutiny than ever before and many countries adopted guideline values based on total alpha and total beta activity measurements. Although most waters from surface circulation meet these guidelines, it is frequently found that groundwater exceed guideline values. Results of water analyses by alpha spectrometry clarified that the main radionuclides present are from the uranium decay series, such as uranium isotopes, radium (226Ra), radon (222Rn), and also 210Pb and 210Po. Occasionally, groundwater displayed 226Ra concentrations higher than 1 Bq L-1 and 222Rn concentrations above 1000 Bq L-1. Nevertheless, lack of conformity of these waters with guidelines adopted, generally, is not due to anthropogenic inputs.

  3. Naturally-Occurring Radionuclides In Drinking Water From Surface And Groundwater Reservoirs

    SciTech Connect

    Carvalho, F. P.; Madruga, M. J.; Oliveira, J. M.; Lopes, I.; Ferrador, G.; Sequeira, M. M.

    2008-08-07

    Radioactivity in water for human consumption is under closer scrutiny than ever before and many countries adopted guideline values based on total alpha and total beta activity measurements. Although most waters from surface circulation meet these guidelines, it is frequently found that groundwater exceed guideline values. Results of water analyses by alpha spectrometry clarified that the main radionuclides present are from the uranium decay series, such as uranium isotopes, radium ({sup 226}Ra), radon ({sup 222}Rn), and also {sup 210}Pb and {sup 210}Po. Occasionally, groundwater displayed {sup 226}Ra concentrations higher than 1 Bq L{sup -1} and {sup 222}Rn concentrations above 1000 Bq L{sup -1}. Nevertheless, lack of conformity of these waters with guidelines adopted, generally, is not due to anthropogenic inputs.

  4. Demonstration of significant abiotic iron isotope fractionation in nature

    USGS Publications Warehouse

    Bullen, T.D.; White, A.F.; Childs, C.W.; Vivit, D.V.; Schultz, M.S.

    2001-01-01

    Field and laboratory studies reveal that the mineral ferrihydrite, formed as a result of abiotic oxidation of aqueous ferrous to ferric Fe, contains Fe that is isotopically heavy relative to coexisting aqueous Fe. Because the electron transfer step of the oxidation process at pH >5 is essentially irreversible and should favor the lighter Fe isotopes in the ferric iron product, this result suggests that relatively heavy Fe isotopes are preferentially partitioned into the readily oxidized Fe(II)(OH)x(aq) species or their transition complexes prior to oxidation. The apparent Fe isotope fractionation factor, ??ferrihydrite-water, depends primarily on the relative abundances of the Fe(II)(aq) species. This study demonstrates that abiotic processes can fractionate the Fe isotopes to the same extent as biotic processes, and thus Fe isotopes on their own do not provide an effective biosignature.

  5. Naturally Occurring Arsenic in Ground Water, Norman, Oklahoma, 2004, and Remediation Options for Produced Water

    USGS Publications Warehouse

    Smith, S. Jerrod; Christenson, Scott

    2005-01-01

    In 2000, the U.S. Environmental Protection Agency (EPA) reviewed the arsenic drinking water standard for public water supplies. Considering the available research and statistics on the health effects of arsenic ingestion, the EPA reduced the Maximum Contaminant Level (MCL) for public drinking water from 50 micrograms per liter (?g/L) to 10 ?g/L (U.S. Environmental Protection Agency, 2001a). As a result of the more stringent standard, the EPA estimates that about 3,000 public water providers across the United States must take action to meet the new standard before it becomes effective on January 23, 2006 (U.S. Environmental Protection Agency, 2001b). The City of Norman (City) is one of several Oklahoma municipalities affected by the new arsenic standard. About 20 percent of Norman?s water is supplied by wells completed in the Central Oklahoma (Garber-Wellington) aquifer; the rest is supplied by Lake Thunderbird (fig. 1) or purchased from Oklahoma City. The Norman well field is composed of 24 active wells, and water produced from about half of the wells will not be in compliance with the new MCL (figs. 2 and 3). Chemical treatment of water with elevated arsenic is possible, but it is generally cost prohibitive. Another costly solution is simply to abandon the high-arsenic wells and replace them with new wells in low-arsenic areas. In the next phase of well construction beginning in 2005, the City plans to construct as many as 30 new wells in northeast Norman (Bryan Mitchell, City of Norman, oral commun., 2005). The new wells will replace production lost to the new arsenic standard and add new production to keep pace with rapidly growing consumer demand. Well modification to exclude arsenic-bearing water from existing wells is a more cost-effective solution, but it requires a great deal of knowledge about local aquifer properties and individual well dynamics to decide which wells are good candidates for modification. With the goal of determining if well modification can be used to bring some of Norman?s high-arsenic wells into compliance with the new arsenic standard, the EPA Office of Research and Development (ORD) initiated a three-year research project in 2003 with participation from the U.S. Geological Survey (USGS), Oklahoma State University, and the City of Norman. The primary objectives of the project are to: (1) determine where naturally occurring arsenic is entering wells by collecting water samples at different depths, (2) investigate the utility of new methods for collecting water-quality data in a pumping well, (3) better understand the stratigraphy and composition of aquifer rocks, (4) assess 10 wells for the possibility of arsenic remediation by well modification, and (5) evaluate the effectiveness of well modification in bringing marginal wells into compliance with the new arsenic MCL. The purpose of this report is to describe the occurrence of arsenic in ground water near Norman, Oklahoma, and available options for reducing arsenic concentrations in produced ground water.

  6. The nitrogen cycle in cryoconites: naturally occurring nitrification-denitrification granules on a glacier.

    PubMed

    Segawa, Takahiro; Ishii, Satoshi; Ohte, Nobuhito; Akiyoshi, Ayumi; Yamada, Akinori; Maruyama, Fumito; Li, Zhongqin; Hongoh, Yuichi; Takeuchi, Nozomu

    2014-10-01

    Cryoconites are microbial aggregates commonly found on glacier surfaces where they tend to take spherical, granular forms. While it has been postulated that the microbes in cryoconite granules play an important role in glacier ecosystems, information on their community structure is still limited, and their functions remain unclear. Here, we present evidence for the occurrence of nitrogen cycling in cryoconite granules on a glacier in Central Asia. We detected marker genes for nitrogen fixation, nitrification and denitrification in cryoconite granules by digital polymerase chain reaction (PCR), while digital reverse transcription PCR analysis revealed that only marker genes for nitrification and denitrification were abundantly transcribed. Analysis of isotope ratios also indicated the occurrence of nitrification; nitrate in the meltwater on the glacier surface was of biological origin, while nitrate in the snow was of atmospheric origin. The predominant nitrifiers on this glacier belonged to the order Nitrosomonadales, as suggested by amoA sequences and 16S ribosomal RNA pyrosequencing analysis. Our results suggest that the intense carbon and nitrogen cycles by nitrifiers, denitrifiers and cyanobacteria support abundant and active microbes on the Asian glacier. PMID:24946985

  7. Naturally occurring radionuclides in food and drinking water from a thorium-rich area.

    PubMed

    da Costa Lauria, Dejanira; Rochedo, Elaine R R; Godoy, Maria Luisa D P; Santos, Eliane E; Hacon, Sandra S

    2012-11-01

    This paper focuses on a survey of uranium and thorium decay chain radionuclides in food and drinking water from the thorium-rich (monazite-bearing) region of Buena, which is located in the state of Rio de Janeiro, Brazil. The radionuclide concentration values in the food and drinking water from Buena reached values higher than 100-fold the international reference values. The daily intake of radionuclides by the local population is similar to that of another high background radiation area in Brazil, but the intake is higher than that of residents from a normal background radiation area. Approximately 58 % of the food consumed by Buena inhabitants is produced locally. Based on that figure, locally produced food and the dilution of total radionuclides in the diet of residents caused by food importation are both highly relevant to a population's intake of radionuclides. The concentration values for (210)Pb and the radium isotopes in drinking water from Buena are among the highest values to be reported in the literature. (228)Ra is the most important radionuclide ingested with both food and water among the inhabitants of Buena. PMID:22782172

  8. Spectroscopic study of major components of dissolved organic matter naturally occurring in water

    SciTech Connect

    Patsayeva, S.; Reuter, R.

    1995-12-31

    Natural organic compounds are present in significant concentration in all types of water. Many organic chemicals found in natural waters can be regarded as products of both biosynthesis and biodegradation. Until now not more than 30% of the dissolved organic matter (DOM) have been chemically characterized. The characterized fraction includes compound classes as carbohydrates, amino acids, hydrocarbons, fatty acids, phenolic compounds and others. The spectroscopic study of dissolved organic matter and its major components is important for applications of lidar remote sensing techniques for water quality measurements. In this paper, fluorescence emission and excitation spectra, as well as absorption spectra for commercially available analogues of major components of gelbstoff are analyzed and compared with spectra of natural water samples of different origin.

  9. RESTORATION OF MUNICIPAL DRINKING WATER SUPPLY WELLS IMPACTED BY NATURALLY OCCURRING ARSENIC

    EPA Science Inventory

    Studies have indicated that arsenic concentrations greater than the newly proposed U.S. Environmental Protection Agency (EPA) maximum contaminant level (MCL) of 10 micrograms per liter (ug/L) occur in specific parts of numerous aquifers around the United States. One such aquifer...

  10. Nitrate dynamics in natural plants: insights based on the concentration and natural isotope abundances of tissue nitrate

    PubMed Central

    Liu, Xue-Yan; Koba, Keisuke; Makabe, Akiko; Liu, Cong-Qiang

    2014-01-01

    The dynamics of nitrate (NO−3), a major nitrogen (N) source for natural plants, has been studied mostly through experimental N addition, enzymatic assay, isotope labeling, and genetic expression. However, artificial N supply may not reasonably reflect the N strategies in natural plants because NO−3 uptake and reduction may vary with external N availability. Due to abrupt application and short operation time, field N addition, and isotopic labeling hinder the elucidation of in situ NO−3-use mechanisms. The concentration and natural isotopes of tissue NO−3 can offer insights into the plant NO−3 sources and dynamics in a natural context. Furthermore, they facilitate the exploration of plant NO−3 utilization and its interaction with N pollution and ecosystem N cycles without disturbing the N pools. The present study was conducted to review the application of the denitrifier method for concentration and isotope analyses of NO−3 in plants. Moreover, this study highlights the utility and advantages of these parameters in interpreting NO−3 sources and dynamics in natural plants. We summarize the major sources and reduction processes of NO−3 in plants, and discuss the implications of NO−3 concentration in plant tissues based on existing data. Particular emphasis was laid on the regulation of soil NO−3 and plant ecophysiological functions in interspecific and intra-plant NO−3 variations. We introduce N and O isotope systematics of NO−3 in plants and discuss the principles and feasibilities of using isotopic enrichment and fractionation factors; the correlation between concentration and isotopes (N and O isotopes: δ18O and Δ17O); and isotope mass-balance calculations to constrain sources and reduction of NO−3 in possible scenarios for natural plants are deliberated. Finally, we offer a preliminary framework of intraplant δ18O-NO−3 variation, and summarize the uncertainties in using tissue NO−3 parameters to interpret plant NO−3 utilization. PMID:25101106

  11. Determination of lithium isotopes at natural abundance levels by atomic absorption spectrometry

    USGS Publications Warehouse

    Meier, A.L.

    1982-01-01

    The relationships of the absorption of 6Li and 7Li hollow cathode lamp emissions are used to determine lithium isotopic composition in the natural abundance range of geologic materials. Absorption was found to have a nonlinear dependence upon total lithium concentration and isotopic composition. A method using nonlinear equations to describe the relationship of the absorption of 6Li and 7Li lamp radiation is proposed as a means of calculating isotopic composition that is independent of total lithium concentration.

  12. Surface complexation modeling of uranium adsorption on naturally occurring iron coated sediments

    SciTech Connect

    Dicke, C.A.; Smith, R.W.

    1996-10-01

    Numerous surface complexation models (SCM) have been developed to describe the adsorption of metals and radionuclides onto oxide surfaces. These models differ primarily in how the electrostatic properties of the double layer are represented. Efforts have been made to develop internally consistent model specific SCM parameters for metal adsorption on single oxide surfaces (e.g., ferrihydrite, goethite, hematite, etc.). Although this approach is valid for well characterized synthetic minerals or mineral isolates, its applicability is less clear for natural soils and sediments containing mixed oxides. Natural materials are considered with the assumption that the total number of a given reactive site type (e.g., Fe[III]-OH) has a more significant impact on adsorption than crystallographic considerations. This assumption is evaluated by comparing the SCM constants determined for adsorption of uranium on three single iron oxide minerals with SCM constants determined for naturally coated iron oxide sediments. The results suggest that given the variability of natural materials, this simplifying assumption is appropriate.

  13. A NATURALLY OCCURRING EPIGENETIC MUTATION IN AN SBP-BOX GENE INHIBITS TOMATO FRUIT RIPENING

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A major player in the regulatory network controlling fruit ripening is likely to be the gene at the tomato Colorless non-ripening (Cnr) locus 1,2. The Cnr mutation results in colorless fruits with a significant loss of cell to cell adhesion. The nature of the mutation and the identity of the Cnr g...

  14. Elemental, stable isotopic and biochemical characterization of soil organic matter alteration across a natural peatland gradient

    NASA Astrophysics Data System (ADS)

    Cowie, G.; Mowbray, S.; Belyea, L.; Laing, C.; Allton, K.; Abbott, G.; Muhammad, A.

    2010-12-01

    Northern peatlands store around one third of global soil C and thus represent a key reservoir. To elucidate how these systems might respond to climate change, field- and laboratory-based experimental incubation studies are being conducted at sites across a natural peatland gradient in the boreonemoral zone of central Sweden (Ryggmossen). The site comprises four successional stages, from edge to centre; Swamp Forest (SF), Lagg Fen (LF), Bog Margin (BM) and Bog Plateau (BP). The well-preserved succession shows strong decreases in mineral cations and pH, and distinct changes in vegetation and water-table depth. As an underpinning to these experiments, comprehensive characterization of natural soil organic matter (SOM) alteration has been carried out through detailed analyses of vegetation and downcore profiles at contrasting topographic sites (hummock vs hollow) in each of the four locations. As illustrated in Figure 1, while some similarities occur in downcore trends, contrasts are observed in C and N elemental and stable isotopic compositions, between stages and, in some cases, between microtopographic settings. Downcore trends and intersite differences are also observed in biochemical yields and molecular composition (carbohydrates, amino acids, phenols, lipids and D/L amino acid ratios). These reflect SOM decay and alteration combined with the effects of contrasting hydrologic, redox and nutrient regimes and differing vegetation and microbial inputs at each of the study sites. Multivariate analysis is used to to elucidate compositional patterns that characterize and delineate progressive SOM decay, specific vegetation types, and the effects of contrasting environmental conditions at the different sites. Figure 1. A. Organic carbon content (wt %), B. Atomic ratio of organic C to total N, C. Stable C isotopic composition of organic C (d13Corg), and D. Stable N isotopic composition of total nitrogen (d15N), all for core profiles from contrasting settings (hummock and hollow) at locations spanning a peatland gradient. Site locations are defined in the text.

  15. Naturally occurring radioactive materials (NORMs) generated from lignite-fired power plants in Kosovo.

    PubMed

    Hasani, F; Shala, F; Xhixha, G; Xhixha, M K; Hodolli, G; Kadiri, S; Bylyku, E; Cfarku, F

    2014-12-01

    The energy production in Kosovo depends primarily on lignite-fired power plants. During coal combustion, huge amounts of fly ash and bottom ash are generated, which may result in enriched natural radionuclides; therefore, these radionuclides need to be investigated to identify the possible processes that may lead to the radiological exposure of workers and the local population. Lignite samples and NORMs of fly ash and bottom ash generated in lignite-fired power plants in Kosovo are analyzed using a gamma-ray spectrometry method for the activity concentration of natural radionuclides. The average activity concentrations of (40)K, (226)Ra and (232)Th in lignite are found to be 36 ± 8 Bq kg(-1), 9 ± 1 Bq kg(-1) and 9 ± 3 Bq kg(-1), respectively. Indications on the occurrence and geochemical behavior of uranium in the lignite matrix are suggested. The activity concentrations of natural radionuclides in fly ash and bottom ash samples are found to be concentrated from 3 to 5 times that of the feeding lignite. The external gamma-ray absorbed dose rate and the activity concentration index are calculated to assess the radiological hazard arising from ash disposal and recycling in the cement industry. PMID:25233215

  16. Naturally occurring variation in tadpole morphology and performance linked to predator regime.

    PubMed

    Johnson, James B; Saenz, Daniel; Adams, Cory K; Hibbitts, Toby J

    2015-08-01

    Divergent natural selection drives a considerable amount of the phenotypic and genetic variation observed in natural populations. For example, variation in the predator community can generate conflicting selection on behavioral, life-history, morphological, and performance traits. Differences in predator regime can subsequently increase phenotypic and genetic variations in the population and result in the evolution of reproductive barriers (ecological speciation) or phenotypic plasticity. We evaluated morphology and swimming performance in field collected Bronze Frog larvae (Lithobates clamitans) in ponds dominated by predatory fish and those dominated by invertebrate predators. Based on previous experimental findings, we hypothesized that tadpoles from fish-dominated ponds would have small bodies, long tails, and large tail muscles and that these features would facilitate fast-start speed. We also expected to see increased tail fin depth (i.e., the tail-lure morphology) in tadpoles from invertebrate-dominated ponds. Our results support our expectations with respect to morphology in affecting swimming performance of tadpoles in fish-dominated ponds. Furthermore, it is likely that divergent natural selection is playing a role in the diversification on morphology and locomotor performance in this system. PMID:26357533

  17. Naturally occurring variation in tadpole morphology and performance linked to predator regime

    PubMed Central

    Johnson, James B; Saenz, Daniel; Adams, Cory K; Hibbitts, Toby J

    2015-01-01

    Divergent natural selection drives a considerable amount of the phenotypic and genetic variation observed in natural populations. For example, variation in the predator community can generate conflicting selection on behavioral, life-history, morphological, and performance traits. Differences in predator regime can subsequently increase phenotypic and genetic variations in the population and result in the evolution of reproductive barriers (ecological speciation) or phenotypic plasticity. We evaluated morphology and swimming performance in field collected Bronze Frog larvae (Lithobates clamitans) in ponds dominated by predatory fish and those dominated by invertebrate predators. Based on previous experimental findings, we hypothesized that tadpoles from fish-dominated ponds would have small bodies, long tails, and large tail muscles and that these features would facilitate fast-start speed. We also expected to see increased tail fin depth (i.e., the tail-lure morphology) in tadpoles from invertebrate-dominated ponds. Our results support our expectations with respect to morphology in affecting swimming performance of tadpoles in fish-dominated ponds. Furthermore, it is likely that divergent natural selection is playing a role in the diversification on morphology and locomotor performance in this system. PMID:26357533

  18. Oxygen isotope signatures of transpired water vapor: the role of isotopic non-steady-state transpiration under natural conditions.

    PubMed

    Dubbert, Maren; Cuntz, Matthias; Piayda, Arndt; Werner, Christiane

    2014-09-01

    The oxygen isotope signature of water is a powerful tracer of water movement from plants to the global scale. However, little is known about the short-term variability of oxygen isotopes leaving the ecosystem via transpiration, as high-frequency measurements are lacking. A laser spectrometer was coupled to a gas-exchange chamber directly estimating branch-level fluxes in order to evaluate the short-term variability of the isotopic composition of transpiration (δE ) and to investigate the role of isotopic non-steady-state transpiration under natural conditions in cork-oak trees (Quercus suber) during distinct Mediterranean seasons. The measured δ(18) O of transpiration (δE ) deviated from isotopic steady state throughout most of the day even when leaf water at the evaporating sites was near isotopic steady state. High agreement was found between estimated and modeled δE values assuming non-steady-state enrichment of leaf water. Isoforcing, that is, the influence of the transpirational δ(18) O flux on atmospheric values, deviated from steady-state calculations but daily means were similar between steady state and non-steady state. However, strong daytime isoforcing on the atmosphere implies that short-term variations in δE are likely to have consequences for large-scale applications, for example, partitioning of ecosystem fluxes or satellite-based applications. PMID:24909361

  19. Investigating Tungsten Concentrations and Isotopic Compositions of Natural Water Samples from the Carson River Basin

    NASA Astrophysics Data System (ADS)

    Wasserman, N. L.; Williams, R. W.; Kayzar, T. M.; Schorzman, K. C.

    2012-12-01

    Recent studies have shown that W-isotopes may fractionate in nature1; however, the magnitude and cause of the isotopic variations are largely unknown and unconstrained. In this study, the isotopic compositions of the NIST 3163 W standard, W ore minerals, and 15 natural surface waters from Nevada's Carson River Basin were analyzed by MC-ICP-MS using external bracketing with NIST 3163 and the IUPAC 184W/183W for mass bias correction. Chemical separation procedures were developed to purify W from natural matrices and tested to assure fractionation was not introduced during column chemistry. The W isotopic compositions of these samples were measured and compared to the accepted IUPAC composition of natural W. Samples of wolframite (Fe, MnWO4) and hubnerite (MnWO4) have compositions similar to the IUPAC value but vary from the isotopic composition of NIST 3163 - particularly in 182W/183W. The isotopic compositions of the natural waters, except for an extremely evaporated sample from Soda Lake, are similar to the NIST standard. This evaporative lake, formed by a maar, has a unique chemical composition compared to other surface waters with high W (800 20 ng/g) and As (1665 17 ng/g) concentrations; and relatively low Fe (5.00 0.13 ng/g) and Mn (0.52 0.07 ng/g). These results support recent observations of natural W isotopic variation and imply that W-isotope compositions may be useful for environmental applications of stable isotope geochemistry. 1. Irisawa, K. and Hirata, T. (2006) Tungsten isotopic analysis on six geochemical reference materials using multiple collector-ICP-mass spectrometry coupled with a rhenium-external correction technique. Journal of Analytical Atomic Spectrometry 21, 1387-1395.

  20. Effect of temperature, pH, and oxygen level on the multiplication of naturally occurring Legionella pneumophila in potable water.

    PubMed Central

    Wadowsky, R M; Wolford, R; McNamara, A M; Yee, R B

    1985-01-01

    A water culture containing naturally occurring Legionella pneumophila and associated microbiota was maintained in the laboratory by serially transferring the culture in tap water which had been sterilized by membrane filtration. Successful maintenance of the water culture depended upon transferring the culture when the growth of L. pneumophila was in the late-exponential to early-stationary phase. The water culture was used as a source of naturally occurring bacteria to determine some of the parameters which affect the multiplication of L. pneumophila in tap water. Naturally occurring L. pneumophila multiplied at a temperature between 25 and 37 degrees C, at pH levels of 5.5 to 9.2, and at concentrations of dissolved oxygen of 6.0 to 6.7 mg/liter. Multiplication did not occur in tap water which contained less than 2.2 mg of dissolved oxygen per liter. An association was observed between the multiplication of L. pneumophila and the non-Legionellaceae bacteria which were also present in the water culture. The method of preserving naturally occurring L. pneumophila and associated microbiota may facilitate studies on the symbiosis of L. pneumophila with other microorganisms. PMID:4004233

  1. NATURAL MERCURY ISOTOPES AS TRACERS OF SOURCES, CYCLING, AND DEPOSITION OF ATMOSPHERIC MERCURY

    EPA Science Inventory

    This research centers on the use of mercury isotope systematics as a new way of investigating natural and anthropogenic emissions of mercury into the atmosphere and of the atmospheric processes that affect transportation and deposition. Given the fact that isotope systematics of ...

  2. Preparation, characterization, and cation exchange selectivity of synthetic and topotactically altered naturally occurring trioctahedral micas

    NASA Astrophysics Data System (ADS)

    Stout, Stephen Anthony

    The large quantity of high level nuclear waste held in underground stainless steel storage tanks around the country has necessitated the need for inorganic ion exchange materials with the ability to selectively remove radioactive species such as 137Cs and 90Sr in the presence of large concentrations of competing cations. Sodium expandable micas, such as sodium fluorophlogopite and K-depleted phlogopite have shown promise for this purpose. During this research highly charged sodium fluorophlogopite micas, Nax(Mg3)[AlxSi4-x]O 10F2yH2O, with layer charges of -2, -3, and -4 per unit cell were synthesized from a dry mix of poorly crystalline kaolinite, Mg(NO3)2, and NaF. Additional silicon was also added to the reaction mixture in the form of amorphous SiO2 to increase the Si:Al ratio as needed. Talc was also utilized for the first time as Si and Mg sources in the synthesis of Na-2-mica. Potassium-depleted phlogopite, K1-xNax(Mg3)[AlSi3]O 10(OH)2, was prepared by conventional and microwave assisted equilibration of <45mum phlogopite mica with a solution containing sodium tetraphenylborate. The synthesized materials were characterized using X-ray diffraction, scanning electron microscopy, magic angle spinning nuclear magnetic resonance, and wet chemical techniques. Three synthetic sodium fluorophlogopite micas and one K-depleted phlogopite sample were selected for ion exchange studies. Ion exchange isotherms for the synthetic sodium fluorophlogopite micas were obtained for Cs+, Sr2+, Ba2+, and Co2+. For the K-depleted phlogopite ion exchange isotherms for Cs+ and Sr2+ were determined. The ion exchange studies indicated that only the Na-2-mica was selective for Cs+, all three micas were selective for Sr2+. All three mica also appeared to be highly selective for both Ba2+ and Co2+. The ion exchange studies indicated that the K-depleted phlogopite was highly selective for both Cs+ and Sr 2+. The ion selectivity of all of these micas indicates that they may be useful not only for removal of radioactive isotopes from the nuclear waste stream, but also removal of transition metal cations from industrial wastes.

  3. When a natural disaster occurs: lessons learned in meeting students' needs.

    PubMed

    Watson, Pamela G; Loffredo, Vincent J; McKee, John C

    2011-01-01

    Across the nation, weather-related natural disasters-tropical storms, floods, tornadoes, and earthquakes-struck even areas where weather concerns are not paramount on the minds of most people. These natural disasters heightened awareness that all geographic areas are susceptible to aberrant weather conditions. The purpose of this article was to relate the lessons learned by one academic health center in meeting students' emergency preparedness and disaster recovery needs following a major hurricane in fall 2008. To gauge students' storm-related needs, a Hurricane Needs Survey (HNS) was conducted in spring 2009, 7 months after the hurricane. Students responded to 26 structured response items and 3 open-ended questions. Five hundred fifteen surveys were completed, constituting a response rate of 37.2%. Data were analyzed by creating frequencies to profile students' hurricane experiences. Results indicated that all students left the island under mandatory evacuation orders; most stayed with their families, and most experienced moderate material losses. For some students, the evacuation process and life after the storm contributed to ongoing problems, worries, and academic performance issues. Qualitative content analysis was used to derive themes from the students' narrative responses to the HNS open-ended questions about their perceptions of the extent to which the University of Texas Medical Branch met their needs. When students' hurricane response comments were analyzed, three major themes emerged: being prepared, needing to be connected, and returning to normalcy. The major lessons learned are that the emergency preparation of students requires greater specificity and that discussion about poststorm recovery expectations is essential. Following a natural disaster, students experience more distress than may be readily apparent. PMID:22142912

  4. Comparison of reactive transport model predictions for natural attenuation processes occurring at chlorinated solvent contaminated site

    NASA Astrophysics Data System (ADS)

    Chiu, H. M.; Tsai, C. H.; Lai, K. H.; Chen, J. S.

    2014-12-01

    Prediction of an analytical model and numerical model, namely BIOCLOR and HYDRODEOCHEM, for a test scenario involving the natural attenuations of dissolved solvent at chlorinated contaminated site are compared. Two models make same predictions for PCE, TCE and DCE and considerable different predictions for VC and ETH for the case of all species having identical retardation factors. Significant discrepancies between two models are observed for all species when retardation coefficients are considered to be different for all species. These differences can be attributed to the basic assumption that all the species have the same retardation factors embedded in BIOCHLOR.

  5. Characterization of calcium isotopes in natural and synthetic barite

    USGS Publications Warehouse

    Griffith, E.M.; Schauble, E.A.; Bullen, T.D.; Paytan, A.

    2008-01-01

    The mineral barite (BaSO4) accommodates calcium in its crystal lattice, providing an archive of Ca-isotopes in the highly stable sulfate mineral. Holocene marine (pelagic) barite samples from the major ocean basins are isotopically indistinguishable from each other (??44/40Ca = -2.01 ?? 0.15???) but are different from hydrothermal and cold seep barite samples (??44/40Ca = -4.13 to -2.72???). Laboratory precipitated (synthetic) barite samples are more depleted in the heavy Ca-isotopes than pelagic marine barite and span a range of Ca-isotope compositions, ??44/40Ca = -3.42 to -2.40???. Temperature, saturation state, a Ba2 + / a SO42 -, and aCa2+/aBa2+ each influence the fractionation of Ca-isotopes in synthetic barite; however, the fractionation in marine barite samples is not strongly related to any measured environmental parameter. First-principles lattice dynamical modeling predicts that at equilibrium Ca-substituted barite will have much lower 44Ca/40Ca than calcite, by -9??? at 0 ??C and -8??? at 25 ??C. Based on this model, none of the measured barite samples appear to be in isotopic equilibrium with their parent solutions, although as predicted they do record lower ??44/40Ca values than seawater and calcite. Kinetic fractionation processes therefore most likely control the extent of isotopic fractionation exhibited in barite. Potential fractionation mechanisms include factors influencing Ca2+ substitution for Ba2+ in barite (e.g. ionic strength and trace element concentration of the solution, competing complexation reactions, precipitation or growth rate, temperature, pressure, and saturation state) as well as nucleation and crystal growth rates. These factors should be considered when investigating controls on isotopic fractionation of Ca2+ and other elements in inorganic and biogenic minerals. ?? 2008 Elsevier Ltd.

  6. Characterization of calcium isotopes in natural and synthetic barite

    NASA Astrophysics Data System (ADS)

    Griffith, Elizabeth M.; Schauble, Edwin A.; Bullen, Thomas D.; Paytan, Adina

    2008-12-01

    The mineral barite (BaSO 4) accommodates calcium in its crystal lattice, providing an archive of Ca-isotopes in the highly stable sulfate mineral. Holocene marine (pelagic) barite samples from the major ocean basins are isotopically indistinguishable from each other (? 44/40Ca = -2.01 0.15) but are different from hydrothermal and cold seep barite samples (? 44/40Ca = -4.13 to -2.72). Laboratory precipitated (synthetic) barite samples are more depleted in the heavy Ca-isotopes than pelagic marine barite and span a range of Ca-isotope compositions, ? 44/40Ca = -3.42 to -2.40. Temperature, saturation state, aBa/aSO42-, and aCa 2+/ aBa 2+ each influence the fractionation of Ca-isotopes in synthetic barite; however, the fractionation in marine barite samples is not strongly related to any measured environmental parameter. First-principles lattice dynamical modeling predicts that at equilibrium Ca-substituted barite will have much lower 44Ca/ 40Ca than calcite, by -9 at 0 C and -8 at 25 C. Based on this model, none of the measured barite samples appear to be in isotopic equilibrium with their parent solutions, although as predicted they do record lower ? 44/40Ca values than seawater and calcite. Kinetic fractionation processes therefore most likely control the extent of isotopic fractionation exhibited in barite. Potential fractionation mechanisms include factors influencing Ca 2+ substitution for Ba 2+ in barite (e.g. ionic strength and trace element concentration of the solution, competing complexation reactions, precipitation or growth rate, temperature, pressure, and saturation state) as well as nucleation and crystal growth rates. These factors should be considered when investigating controls on isotopic fractionation of Ca 2+ and other elements in inorganic and biogenic minerals.

  7. The source of naturally occurring arsenic in a coastal sand aquifer of eastern Australia.

    PubMed

    O'Shea, Bethany; Jankowski, Jerzy; Sammut, Jesmond

    2007-07-01

    The discovery of dissolved arsenic in a coastal aquifer used extensively for human consumption has led to widespread concern for its potential occurrence in other sandy coastal environments in eastern Australia. The development of an aquifer specific geomorphic model (herein) suggests that arsenic is regionally derived from erosion of arsenic-rich stibnite (Sb(2)S(3)) mineralisation present in the hinterland. Fluvial processes have transported the eroded material over time to deposit an aquifer lithology elevated in arsenic. Minor arsenic contribution to groundwater is derived from mineralised bedrock below the unconsolidated aquifer. An association with arsenic and pyrite has been observed in the aquifer in small discrete arsenian pyrite clusters rather than actual acid sulfate soil horizons. This association is likely to influence arsenic distribution in the aquifer, but is not the dominant control on arsenic occurrence. Arsenic association with marine clays is considered a function of their increased adsorptive capacity for arsenic and not solely on the influence of sea level inundation of the aquifer sediments during the Quaternary Period. These findings have implications for, but are not limited to, coastal aquifers. Rather, any aquifer containing sediments derived from mineralised provenances may be at risk of natural arsenic contamination. Groundwater resource surveys should thus incorporate a review of the aquifer source provenance when assessing the likely risk of natural arsenic occurrence in an aquifer. PMID:17184824

  8. Naturally occurring inhibitors against the formation of advanced glycation end-products.

    PubMed

    Peng, Xiaofang; Ma, Jinyu; Chen, Feng; Wang, Mingfu

    2011-06-01

    Advanced glycation end-products (AGEs) are the final products of the non-enzymatic reaction between reducing sugars and amino groups in proteins, lipids and nucleic acids. Recently, the accumulation of AGEs in vivo has been implicated as a major pathogenic process in diabetic complications, atherosclerosis, Alzheimer's disease and normal aging. The early recognition of AGEs can ascend to the late 1960s when a non-enzymatic glycation process was found in human body which is similar to the Maillard reaction. To some extent, AGEs can be regarded as products of the Maillard reaction. This review firstly introduces the Maillard reaction, the formation process of AGEs and harmful effects of AGEs to human health. As AGEs can cause undesirable diseases or disorders, it is necessary to investigate AGE inhibitors to offer a potential therapeutic approach for the prevention of diabetic or other pathogenic complications induced by AGEs. Typical effective AGE inhibitors with different inhibition mechanisms are also reviewed in this paper. Both synthetic compounds and natural products have been evaluated as inhibitors against the formation of AGEs. However, considering toxic or side effects of synthetic molecules present in clinical trials, natural products are more promising to be developed as potent AGE inhibitors. PMID:21779567

  9. Naturally occurring diversity helps to reveal genes of adaptive importance in legumes

    PubMed Central

    Gentzbittel, Laurent; Andersen, Stig U.; Ben, Cécile; Rickauer, Martina; Stougaard, Jens; Young, Nevin D.

    2015-01-01

    Environmental changes challenge plants and drive adaptation to new conditions, suggesting that natural biodiversity may be a source of adaptive alleles acting through phenotypic plasticity and/or micro-evolution. Crosses between accessions differing for a given trait have been the most common way to disentangle genetic and environmental components. Interestingly, such man-made crosses may combine alleles that never meet in nature. Another way to discover adaptive alleles, inspired by evolution, is to survey large ecotype collections and to use association genetics to identify loci of interest. Both of these two genetic approaches are based on the use of biodiversity and may eventually help us in identifying the genes that plants use to respond to challenges such as short-term stresses or those due to global climate change. In legumes, two wild species, Medicago truncatula and Lotus japonicus, plus the cultivated soybean (Glycine max) have been adopted as models for genomic studies. In this review, we will discuss the resources, limitations and future plans for a systematic use of biodiversity resources in model legumes to pinpoint genes of adaptive importance in legumes, and their application in breeding. PMID:25954294

  10. Introduction to Chemistry and Applications in Nature of Mass Independent Isotope Effects Special Feature

    PubMed Central

    Thiemens, Mark H.

    2013-01-01

    Stable isotope ratio variations are regulated by physical and chemical laws. These rules depend on a relation with mass differences between isotopes. New classes of isotope variation effects that deviate from mass dependent laws, termed mass independent isotope effects, were discovered in 1983 and have a wide range of applications in basic chemistry and nature. In this special edition, new applications of these effects to physical chemistry, solar system origin models, terrestrial atmospheric and biogenic evolution, polar paleo climatology, snowball earth geology, and present day atmospheric sciences are presented. PMID:24167299

  11. Naturally occurring bacteraemia in American lobsters, Homarus americanus Milne-Edwards, in Long Island Sound.

    PubMed

    Bartlett, S L; Wooster, G A; Sokolowski, M S; Dove, A D M; Bowser, P R

    2008-01-01

    The health status of the American lobster, Homarus americanus Milne-Edwards, in Long Island Sound (LIS) has been in decline, with seasonal mortality events occurring since 1998. In order to assess the potential effects of environmental conditions on lobster health via haemolymph analysis, lobsters collected from various sites in LIS were examined and sampled while concurrent environmental data (water temperature, salinity and dissolved oxygen) were recorded. The pH of the haemolymph of each lobster was tested, followed by a collection of haemolymph for serum biochemistry analysis and bacterial culture. This report focuses on the results of the bacterial sampling. The majority of bacteria cultured were opportunistic pathogens commonly found in the environment, including some that are associated with sewage and pollution. The prevalence of bacteraemia was correlated with the site of collection, the month in which the lobsters were sampled, and water temperature. PMID:18086031

  12. Sequestering carbon dioxide into complex structures of naturally occurring gas hydrates

    PubMed Central

    Park, Youngjune; Kim, Do-Youn; Lee, Jong-Won; Huh, Dae-Gee; Park, Keun-Pil; Lee, Jaehyoung; Lee, Huen

    2006-01-01

    Large amounts of CH4 in the form of solid hydrates are stored on continental margins and in permafrost regions. If these CH4 hydrates could be converted into CO2 hydrates, they would serve double duty as CH4 sources and CO2 storage sites. We explore here the swapping phenomenon occurring in structure I (sI) and structure II (sII) CH4 hydrate deposits through spectroscopic analyses and its potential application to CO2 sequestration at the preliminary phase. The present 85% CH4 recovery rate in sI CH4 hydrate achieved by the direct use of binary N2 + CO2 guests is surprising when compared with the rate of 64% for a pure CO2 guest attained in the previous approach. The direct use of a mixture of N2 + CO2 eliminates the requirement of a CO2 separation/purification process. In addition, the simultaneously occurring dual mechanism of CO2 sequestration and CH4 recovery is expected to provide the physicochemical background required for developing a promising large-scale approach with economic feasibility. In the case of sII CH4 hydrates, we observe a spontaneous structure transition of sII to sI during the replacement and a cage-specific distribution of guest molecules. A significant change of the lattice dimension caused by structure transformation induces a relative number of small cage sites to reduce, resulting in the considerable increase of CH4 recovery rate. The mutually interactive pattern of targeted guest–cage conjugates possesses important implications for the diverse hydrate-based inclusion phenomena as illustrated in the swapping process between CO2 stream and complex CH4 hydrate structure. PMID:16908854

  13. Genetic architecture of naturally occurring quantitative traits in plants: an updated synthesis.

    PubMed

    Alonso-Blanco, Carlos; Mndez-Vigo, Beln

    2014-04-01

    Deciphering the genetic and molecular bases of quantitative variation is a long-standing challenge in plant biology because it is essential for understanding evolution and for accelerating plant breeding. Recent multi-trait analyses at different phenotypic levels are uncovering the pleiotropy and the genetic regulation underlying high-level complex traits. Thus, the number of known causal loci, genes and nucleotide polymorphisms is expanding. Current plant causal catalogs contain ?400 genes and natural polymorphisms revealing several dysfunctional allelic series that involve multiple mutations. In addition, repeated evolution of quantitative traits mediated by large effect alleles is found across plant phylogeny. Finally, systematic analyses of genetic and environmental interactions are beginning to elucidate the molecular mechanisms of relevant interactions. PMID:24565952

  14. Naturally occurring radionuclides and rare earth elements in weathered Japanese soil samples

    NASA Astrophysics Data System (ADS)

    Sahoo, Sarata; Hosoda, Masahiro; Prasad, Ganesh; Takahashi, Hiroyuki; Sorimachi, Atsuyuki; Ishikawa, Tetsuo; Tokonami, Shinji; Uchida, Shigeo

    2013-08-01

    The activity concentrations of 226Ra and 228Ac in weathered Japanese soils from two selected prefectures have been measured using a ?-ray spectroscopy system with high purity germanium detector. The uranium, thorium, and rare earth elements (REEs) concentrations were determined from the same soil samples using inductively coupled plasma mass spectrometry (ICP-MS). For example, granitic rocks contain higher amounts of U, Th, and light REEs compared to other igneous rocks such as basalt and andesites. Therefore, it is necessary to understand the interaction between REEs and nature of soils since soils are complex heterogeneous mixture of organic and inorganic solids, water, and gases. In this paper, we will discuss about distribution pattern of 238U and 232Th along with REEs in soil samples of weathered acid rock (granite) collected from two prefectures of Japan: Hiroshima and Miyagi.

  15. Baseline data of naturally occurring radionuclides in some native vegetables and fruits in Southern Thailand.

    PubMed

    Kranrod, C; Chanyotha, S; Pornnumpa, C; Kritsananuwat, R; Sriploy, P

    2015-11-01

    The aim of this study was to provide the baseline data information on natural radioactivities in vegetables and fruits produced and consumed locally in the areas of potential nuclear power plant sites in Thailand. Four provinces (Prajuab-Kirikhan, Chumphon, Surat-Thani and Nakhon-Si-thammarat) were selected for collection of native vegetables and fruits samples, together with their corresponding soils. The activities of (226)Ra, (228)Ra, (40)K and (210)Po were determined in all these samples. The obtained results for (226)Ra, (228)Ra, (40)K and (210)Po for all vegetable and fruit samples were in the range of 1-34, 1-108, 32-4392 and 0.2-47 Bq kg(-1), respectively, which were much lower than those obtained for their corresponding soils. PMID:25944964

  16. Fluoride: A naturally-occurring health hazard in drinking-water resources of Northern Thailand.

    PubMed

    Chuah, C Joon; Lye, Han Rui; Ziegler, Alan D; Wood, Spencer H; Kongpun, Chatpat; Rajchagool, Sunsanee

    2016-03-01

    In Northern Thailand, incidences of fluorosis resulting from the consumption of high-fluoride drinking-water have been documented. In this study, we mapped the high-fluoride endemic areas and described the relevant transport processes of fluoride in enriched waters in the provinces of Chiang Mai and Lamphun. Over one thousand surface and sub-surface water samples including a total of 995 collected from shallow (depth: ≤30m) and deep (>30m) wells were analysed from two unconnected high-fluoride endemic areas. At the Chiang Mai site, 31% of the shallow wells contained hazardous levels (≥1.5mg/L) of fluoride, compared with the 18% observed in the deep wells. However, at the Lamphun site, more deep wells (35%) contained water with at least 1.5mg/L fluoride compared with the shallow wells (7%). At the Chiang Mai site, the high-fluoride waters originate from a nearby geothermal field. Fluoride-rich geothermal waters are distributed across the area following natural hydrological pathways of surface and sub-surface water flow. At the Lamphun site, a well-defined, curvilinear high-fluoride anomalous zone, resembling that of the nearby conspicuous Mae Tha Fault, was identified. This similarity provides evidence of the existence of an unmapped, blind fault as well as its likely association to a geogenic source (biotite-granite) of fluoride related to the faulted zone. Excessive abstraction of ground water resources may also have affected the distribution and concentration of fluoride at both sites. The distribution of these high-fluoride waters is influenced by a myriad of complex natural and anthropogenic processes which thus created a challenge for the management of water resources for safe consumption in affected areas. The notion of clean and safe drinking water can be found in deeper aquifers is not necessarily true. Groundwater at any depth should always be tested before the construction of wells. PMID:26747991

  17. Relative Resistance of HLA-B to Downregulation by Naturally Occurring HIV-1 Nef Sequences

    PubMed Central

    Mahiti, Macdonald; Toyoda, Mako; Jia, Xiaofei; Kuang, Xiaomei T.; Mwimanzi, Francis; Mwimanzi, Philip; Walker, Bruce D.; Xiong, Yong; Brumme, Zabrina L.; Brockman, Mark A.

    2016-01-01

    ABSTRACT HIV-1 Nef binds to the cytoplasmic region of HLA-A and HLA-B and downregulates these molecules from the surface of virus-infected cells, thus evading immune detection by CD8+ T cells. Polymorphic residues within the HLA cytoplasmic region may affect Nefs downregulation activity. However, the effects of HLA polymorphisms on recognition by primary Nef isolates remain elusive, as do the specific Nef regions responsible for downregulation of HLA-A versus HLA-B. Here, we examined 46 Nef clones isolated from chronically HIV-1 subtype B-infected subjects for their ability to downregulate various HLA-A, HLA-B, and HLA-C molecules on the surface of virus-infected cells. Overall, HLA-B exhibited greater resistance to Nef-mediated downregulation than HLA-A, regardless of the cell type examined. As expected, no Nef clone downregulated HLA-C. Importantly, the differential abilities of patient-derived Nef clones to downregulate HLA-A and HLA-B correlated inversely with the sensitivities of HIV-infected target cells to recognition by effector cells expressing an HIV-1 Gag-specific T cell receptor. Nef codon function analysis implicated amino acid variation at position 202 (Nef-202) in differentially affecting the ability to downregulate HLA-A and HLA-B, an observation that was subsequently confirmed by experiments using Nef mutants constructed by site-directed mutagenesis. The in silico and mutagenesis analyses further suggested that Nef-202 may interact with the C-terminal Cys-Lys-Val residues of HLA-A, which are absent in HLA-B. Taken together, the results show that natural polymorphisms within Nef modulate its interaction with natural polymorphisms in the HLA cytoplasmic tails, thereby affecting the efficiency of HLA downregulation and consequent recognition by HIV-specific T cells. These results thus extend our understanding of this complex pathway of retroviral immune evasion. PMID:26787826

  18. Naturally occurring mutations to HCV protease inhibitors in treatment-nave patients

    PubMed Central

    2012-01-01

    Background Protease inhibitors (PIs) to treat hepatitis C (HCV) virus infection have been approved and others are under development. Results The aims of this study were to illustrate natural polymorphisms in the HCV protease and measure the frequency of PI resistance mutations in different HCV genotypes from PI-nave patients. Direct sequencing of HCV NS3/4A protease was performed in 156 HCV patients nave to PIs who were infected with genotype 1a (n?=?31), 1b (n?=?39), 2 (n?=?30), 3 (n?=?33) and 4 (n?=?23). Amino acid (aa) substitutions associated with HCV PI resistance were found in 17/156 (10.8%) sequences. Mutations V36L, T54S, V55A/I, and Q80K/L were observed in 29% of patients with genotype 1a, and V55F, Q80L/N and M175L in 10% of patients with genotype 1b. The mutation V158M was found in 3% of patients with genotype 2, D168Q was present in 100% of patients with genotype 3 and D168E was observed in 13% of patients with genotype 4. In addition, multiple aa polymorphisms not associated with PI resistance were detected in patients with genotypes 1a, 1b and 4. Conclusions Although major PI resistance mutations were not detected, other resistance mutations conferring low level resistance to PIs together with a number of natural polymorphisms were observed in proteases of PI nave HCV patients. A more extensive analysis is needed to better evaluate the impact of baseline resistance and compensatory mutations in the efficacy of HCV PI treatment. PMID:23095680

  19. The Case of an In-Home Recreation Program for an Older Adult in a Naturally Occurring Retirement Community (NORC).

    ERIC Educational Resources Information Center

    Chow, Yvette

    2002-01-01

    Describes the implementation of an in-home therapeutic recreation (TR) program with an elderly woman living in a naturally occurring retirement community (NORC) by a fourth-year TR student. The program helped meet her physical, social, and cognitive needs and re-stimulate her interests. Results suggest that in-home TR can be beneficial, and TR…

  20. Evaluation of the Fate of Naturally Occurring Escherichia coli O157:H7 During Bovine Manure Composting Processes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Foodborne illnesses associated with produce consumption have brought attention to livestock manure composts as potential sources of pathogens for the contamination of these crops. Our objective was to determine the fate of naturally-occurring E. coli O157:H7 during minimally managed on-farm bovin...

  1. Recruiting Older Adults into a Physical Activity Promotion Program: "Active Living Every Day" Offered in a Naturally Occurring Retirement Community

    ERIC Educational Resources Information Center

    Hildebrand, Mary; Neufeld, Peggy

    2009-01-01

    Purpose: This article explores recruitment strategies based on the transtheoretical model (TTM) with older adults living in a naturally occurring retirement community (NORC) to encourage enrollment in a physical activity promotion program, "Active Living Every Day" (ALED). Reasons for participation or nonparticipation are identified. Design and

  2. Elevated Appraisals of the Negative Impact of Naturally Occurring Life Events: A Risk Factor for Depressive and Anxiety Disorders

    ERIC Educational Resources Information Center

    Espejo, Emmanuel Peter; Hammen, Constance; Brennan, Patricia A.

    2012-01-01

    The tendency to appraise naturally occurring life events (LEs) as having high negative impact may be a predisposing factor for the development of depression and anxiety disorders. In the current study, appraisals of the negative impact of recent LEs were examined in relationship to depressive and anxiety disorders in a sample of 653 adolescents…

  3. The Nature, Occurring Contexts, and Psychological Implications of Weight-Related Teasing in Urban Physical Education Programs

    ERIC Educational Resources Information Center

    Li, Weidong; Rukavina, Paul

    2012-01-01

    This study examined the nature, occurring contexts, and psychological implications of weight-related teasing in urban physical education programs. Semistructured interviews were conducted with 47 participants from a large urban school district. Data were analyzed using inductive analysis and constant comparisons. Most overweight adolescents

  4. Elevated Appraisals of the Negative Impact of Naturally Occurring Life Events: A Risk Factor for Depressive and Anxiety Disorders

    ERIC Educational Resources Information Center

    Espejo, Emmanuel Peter; Hammen, Constance; Brennan, Patricia A.

    2012-01-01

    The tendency to appraise naturally occurring life events (LEs) as having high negative impact may be a predisposing factor for the development of depression and anxiety disorders. In the current study, appraisals of the negative impact of recent LEs were examined in relationship to depressive and anxiety disorders in a sample of 653 adolescents

  5. A novel Arometic compound acts synergistically with a naturally occurring monoterpene to elicit strong behavioral responses in Asian citrus psyllid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Inscent, Inc. has developed methodologies for rapidly screening potential ligands of chemosensory proteins (CSPs) isolated from the antennae of target insects. These novel ligands, referred to as Arometics, mimic naturally-occurring odorants and may function as super-stimuli because of their strong ...

  6. Recruiting Older Adults into a Physical Activity Promotion Program: "Active Living Every Day" Offered in a Naturally Occurring Retirement Community

    ERIC Educational Resources Information Center

    Hildebrand, Mary; Neufeld, Peggy

    2009-01-01

    Purpose: This article explores recruitment strategies based on the transtheoretical model (TTM) with older adults living in a naturally occurring retirement community (NORC) to encourage enrollment in a physical activity promotion program, "Active Living Every Day" (ALED). Reasons for participation or nonparticipation are identified. Design and…

  7. Sporadic naturally occurring melanoma in dogs as a preclinical model for human melanoma

    PubMed Central

    Simpson, R Mark; Bastian, Boris C; Michael, Helen T; Webster, Joshua D; Prasad, Manju L; Conway, Catherine M; Prieto, Victor M; Gary, Joy M; Goldschmidt, Michael H; Esplin, D Glen; Smedley, Rebecca C; Piris, Adriano; Meuten, Donald J; Kiupel, Matti; Lee, Chyi-Chia R; Ward, Jerrold M; Dwyer, Jennifer E; Davis, Barbara J; Anver, Miriam R; Molinolo, Alfredo A; Hoover, Shelley B; Rodriguez-Canales, Jaime; Hewitt, Stephen M

    2014-01-01

    Melanoma represents a significant malignancy in humans and dogs. Different from genetically engineered models, sporadic canine melanocytic neoplasms share several characteristics with human disease that could make dogs a more relevant preclinical model. Canine melanomas rarely arise in sun-exposed sites. Most occur in the oral cavity, with a subset having intra-epithelial malignant melanocytes mimicking the in situ component of human mucosal melanoma. The spectrum of canine melanocytic neoplasia includes benign lesions with some analogy to nevi, as well as invasive primary melanoma, and widespread metastasis. Growing evidence of distinct subtypes in humans, differing in somatic and predisposing germ-line genetic alterations, cell of origin, epidemiology, relationship to ultraviolet radiation and progression from benign to malignant tumors, may also exist in dogs. Canine and human mucosal melanomas appear to harbor BRAF, NRAS, and c-kit mutations uncommonly, compared with human cutaneous melanomas, although both species share AKT and MAPK signaling activation. We conclude that there is significant overlap in the clinical and histopathological features of canine and human mucosal melanomas. This represents opportunity to explore canine oral cavity melanoma as a preclinical model. PMID:24128326

  8. Sulphoraphane, a naturally occurring isothiocyanate induces apoptosis in breast cancer cells by targeting heat shock proteins

    SciTech Connect

    Sarkar, Ruma; Mukherjee, Sutapa; Biswas, Jaydip; Roy, Madhumita

    2012-10-12

    Highlights: Black-Right-Pointing-Pointer HSPs (27, 70 and 90) and HSF1 are overexpressed in MCF-7 and MDA-MB-231 cells. Black-Right-Pointing-Pointer Sulphoraphane, a natural isothiocyanate inhibited HSPs and HSF1 expressions. Black-Right-Pointing-Pointer Inhibition of HSPs and HSF1 lead to regulation of apoptotic proteins. Black-Right-Pointing-Pointer Alteration of apoptotic proteins activate of caspases particularly caspase 3 and 9 leading to induction of apoptosis. Black-Right-Pointing-Pointer Alteration of apoptotic proteins induce caspases leading to induction of apoptosis. -- Abstract: Heat shock proteins (HSPs) are involved in protein folding, aggregation, transport and/or stabilization by acting as a molecular chaperone, leading to inhibition of apoptosis by both caspase dependent and/or independent pathways. HSPs are overexpressed in a wide range of human cancers and are implicated in tumor cell proliferation, differentiation, invasion and metastasis. HSPs particularly 27, 70, 90 and the transcription factor heat shock factor1 (HSF1) play key roles in the etiology of breast cancer and can be considered as potential therapeutic target. The present study was designed to investigate the role of sulphoraphane, a natural isothiocyanate on HSPs (27, 70, 90) and HSF1 in two different breast cancer cell lines MCF-7 and MDA-MB-231 cells expressing wild type and mutated p53 respectively, vis-a-vis in normal breast epithelial cell line MCF-12F. It was furthermore investigated whether modulation of HSPs and HSF1 could induce apoptosis in these cells by altering the expressions of p53, p21 and some apoptotic proteins like Bcl-2, Bax, Bid, Bad, Apaf-1 and AIF. Sulphoraphane was found to down-regulate the expressions of HSP70, 90 and HSF1, though the effect on HSP27 was not pronounced. Consequences of HSP inhibition was upregulation of p21 irrespective of p53 status. Bax, Bad, Apaf-1, AIF were upregulated followed by down-regulation of Bcl-2 and this effect was prominent in MCF-7 than in MDA-MB-231. However, very little change in the expression of Bid was observed. Alteration in Bcl-2 Bax ratio resulted in the release of cytochrome c from mitochondria and activation of caspases 3 and 9 which are in agreement with apoptotic index values. Sulphoraphane therefore can be regarded as a potent inducer of apoptosis due to HSP modulation in breast cancer cells.

  9. Interactions between natural-occurring landscape conditions and land use influencing the abundance of riverine smallmouth bass, micropterus dolomieu

    USGS Publications Warehouse

    Brewer, S.K.; Rabeni, C.F.

    2011-01-01

    This study examined how interactions between natural landscape features and land use influenced the abundance of smallmouth bass, Micropterus dolomieu, in Missouri, USA, streams. Stream segments were placed into one of four groups based on natural-occurring watershed characteristics (soil texture and soil permeability) predicted to relate to smallmouth bass abundance. Within each group, stream segments were assigned forest (n = 3), pasture (n = 3), or urban (n = 3) designations based on the percentages of land use within each watershed. Analyses of variance indicated smallmouth bass densities differed between land use and natural conditions. Decision tree models indicated abundance was highest in forested stream segments and lowest in urban stream segments, regardless of group designation. Land use explained the most variation in decision tree models, but in-channel features of temperature, flow, and sediment also contributed significantly. These results are unique and indicate the importance of natural-occurring watershed conditions in defining the potential of populations and how finer-scale filters interact with land use to further alter population potential. Smallmouth bass has differing vulnerabilities to land-use attributes, and the better the natural watershed conditions are for population success, the more resilient these populations will be when land conversion occurs.

  10. Effect of synthetic and naturally occurring chalcones on ovarian cancer cell growth: structure-activity relationships.

    PubMed

    De Vincenzo, R; Scambia, G; Benedetti Panici, P; Ranelletti, F O; Bonanno, G; Ercoli, A; Delle Monache, F; Ferrari, F; Piantelli, M; Mancuso, S

    1995-09-01

    This study was carried out to determine the effect of 15 different natural and synthetic chalcones on the proliferation of both established and primary ovarian cancer cells expressing type II oestrogen binding sites (type II EBS). The binding affinity of chalcones for type II EBS was also tested. At concentrations from 0.1 to 10 microM, chalcones inhibited ovarian cancer cell proliferation and [3H]oestradiol ([3H]E2) binding to type II EBS. Considering the structure-related variation in IC50 (concentration resulting in a 50% inhibition of cell growth) and Di50 (concentration resulting in a 50% displacement of [3H]E2 bound to type II EBS), it appeared that the presence of an alpha-beta double bond, the hydroxylation in 3 or 2 of ring B and the absence of a prenyl group were important to both the antiproliferative and binding activity. Structure-related variations in IC50 and Di50 were significantly concordant (Fisher's exact test: P = 0.0291), suggesting that there may be a type II EBS-mediated mechanism for chalcone antiproliferative activity. Our data indicate that chalcones could be considered as potential new anticancer drugs. PMID:7575989

  11. Radiological indices of technologically enhanced naturally occurring radionuclides: a PIXE approach.

    PubMed

    Olise, Felix Samuel; Owoade, Oyediran Kayode; Olaniyi, Hezekiah Bamidele

    2011-06-01

    This paper reports an assessment of the level of the radionuclides (40)K, (232)Th and (238)U in environmental soil samples (process waste), and hence their calculated dose rates. For this purpose, the radioactivity from three natural radionuclides was determined in tin process-waste samples in Jos, Nigeria. This work is based on the particle induced x-ray emission (PIXE) approach, devoid of the secular equilibrium, and most of the resolution, interference, self-absorption, geometrical and density correction problems inherent in gamma spectrometry. Many potential environmental hazards have been observed and the data would be of use to the government in its remediation plan for the study area. The high hazard indices require taking adequate measures to check exposures, and an underground lining in the waste ponds to prevent direct contact with the waste pile is recommended. The use of the wastes as building materials should be stopped and use of soils around this area in any development projects should be discouraged until detailed studies on indoor radiation doses and the effects on the inhabitants of prolonged exposures have been carried out. PMID:21617293

  12. Adaptation for Protein Synthesis Efficiency in a Naturally Occurring Self-Regulating Operon

    PubMed Central

    Herman, Dorota; Thomas, Christopher M.; Stekel, Dov J.

    2012-01-01

    The korAB operon in RK2 plasmids is a beautiful natural example of a negatively and cooperatively self-regulating operon. It has been particularly well characterized both experimentally and with mathematical models. We have carried out a detailed investigation of the role of the regulatory mechanism using a biologically grounded mechanistic multi-scale stochastic model that includes plasmid gene regulation and replication in the context of host growth and cell division. We use the model to compare four hypotheses for the action of the regulatory mechanism: increased robustness to extrinsic factors, decreased protein fluctuations, faster response-time of the operon and reduced host burden through improved efficiency of protein production. We find that the strongest impact of all elements of the regulatory architecture is on improving the efficiency of protein synthesis by reduction in the number of mRNA molecules needed to be produced, leading to a greater than ten-fold reduction in host energy required to express these plasmid proteins. A smaller but still significant role is seen for speeding response times, but this is not materially improved by the cooperativity. The self-regulating mechanisms have the least impact on protein fluctuations and robustness. While reduction of host burden is evident in a plasmid context, negative self-regulation is a widely seen motif for chromosomal genes. We propose that an important evolutionary driver for negatively self-regulated genes is to improve the efficiency of protein synthesis. PMID:23185406

  13. Electrosensory interference in naturally occurring aggregates of a species of weakly electric fish, Eigenmannia virescens.

    PubMed

    Tan, Eric W; Nizar, Jonathan M; Carrera-G, Erika; Fortune, Eric S

    2005-10-14

    The detection and identification of behaviorally relevant signals in the presence of competing signals in the environment is a major challenge of animal sensory systems. In weakly electric fish such as Eigenmannia virescens, the interactions between the autogenous electric field and the electric fields of nearby conspecifics can have profound effects on the perception of other behaviorally relevant electrosensory information. To better understand the natural signals that the nervous system of Eigenmannia experiences during the processing of electrosensory information, we examined the electrosensory milieu of Eigenmannia in the wild and in the laboratory. Recordings of the electric fields of Eigenmannia were made in 'black' and 'white' waters near the Napo River in eastern Ecuador. Fourier analysis revealed that Eigenmannia typically experience the electric fields of three to five conspecifics during the day and night in each habitat. The median difference in electric organ discharge frequencies between nearby Eigenmannia during the day was 23 Hz in black water habitats, 41 Hz in white water, and 37 Hz at night in both habitats: these signals are known to activate tuberous electroreceptors and downstream CNS circuits. There was no correlation between the number of individual Eigenmannia detected at recording sites and electric organ discharge frequencies. Further, Eigenmannia apparently do not maximize the frequency differences between conspecifics. In laboratory studies fish were preferentially observed in aggregates of two fish or more. Aggregate sizes observed in the laboratory were similar to those in the wild. PMID:16099058

  14. Naturally Occurring Compounds Elicit HIV-1 Replication in Chronically Infected Promonocytic Cells

    PubMed Central

    Barquero, Andrea Alejandra; Dávola, María Eugenia; Riva, Diego Ariel; Mersich, Susana Esther; Alché, Laura Edith

    2014-01-01

    Since antiretroviral therapy suppresses but does not eradicate HIV-1 infection, methods to purge viral reservoirs are required. Many strategies involve the reactivation of chronically HIV infected cells to induce the expression of integrated viral genome. In this study, five bioactive compounds, the plant derivatives 1-cinnamoyl-3,11-dihydroxymeliacarpin (CDM), nordihydroguaiaretic acid (NDGA), and curcumin (Cur) and the synthetic stigmasterol analogs (22S,23S)-22,23-dihydroxystigmast-4-en-3-one (compound 1) and (22S,23S)-3β-bromo-5α,22,23-trihydroxystigmastan-6-one (compound 2), were evaluated for their ability to elicit HIV replication in promonocytic (U1) and lymphocytic (H9+) HIV-1 chronically infected cells. The results revealed that natural compounds CDM, NDGA, and Cur were able to increase HIV-1 p24 antigen, determined by ELISA, only in latently infected promonocytic cells. CDM would reactivate HIV from latency by modulating the release of IL-6 and TNF-α, since the amount of both cytokines measured through ELISA significantly increased in U1 treated cells. Besides, NDGA increased ROS production, which might be related to the increase on p24 level observed in NDGA treated U1. These findings suggest that CDM, NDGA, and Cur might be candidates for further studies on latency-reversing therapeutics to eliminate latently HIV-1 reservoirs. PMID:24901006

  15. Laboratory studies using naturally occurring "green rust" to aid metal mine water remediation.

    PubMed

    Bearcock, Jenny M; Perkins, William T; Pearce, Nicholas J G

    2011-06-15

    Green rust, an Fe (II) and (III) oxyhydroxy salt, can alter the aqueous oxidation state, mobility and toxicity, of inorganic contaminants and thus could have applications in water treatment. This paper discusses a series of stirred, open batch experiments designed to evaluate green rust, and its oxidised equivalent in this context comparing it to a ferrihydrite/goethite 'ochre'. Natural green rust was added to different mine waters as either a wet, reduced material or a dry, partially oxidised material. Experiments showed that the addition of either form accelerated the removal of potentially harmful elements from solution. Within one hour Fe, Al and Cu were completely removed from mine waters with initial concentrations of 80, 70 and 8.5mg/L, respectively, and Zn was reduced from 60 to <5mg/L. These experiments show the potential of green rust in mine water treatment, especially as it is able to remove problematic elements such as Al and Zn. The material is effective even after being dried and mostly oxidised. Changes to the pH and ORP of the mine waters and surface catalysis are the suggested mechanisms of accelerated removal of contaminants. PMID:21497995

  16. Pathogenicity of a naturally occurring recombinant DNA satellite associated with tomato yellow leaf curl China virus.

    PubMed

    Tao, Xiaorong; Zhou, Xueping

    2008-01-01

    Recombinant DNA beta molecules (RecDNA-Abeta) comprising parts of DNA A and DNA beta associated with tomato yellow leaf curl China virus (TYLCCNV) have been identified in naturally infected tobacco plants. Several examples of the recombinant DNA have been cloned and characterized by sequence analysis. All are approximately half the size of TYLCCNV genomic DNA, and all contain the betaC1 gene and the A-rich region from TYLCCNV DNA beta as well as intergenic region sequences and the 5' terminus of the AC1 gene from TYLCCNV DNA A. RecDNA-Abeta was detected by PCR in five of 25 TYLCCNV isolates. Co-inoculation of TYLCCNV DNA A and RecDNA-Abeta induced symptoms indistinguishable from those induced by TYLCCNV DNA A and DNA beta in Nicotiana benthamiana, Nicotiana glutinosa, Solanum lycopersicum and Petunia hybrida plants, and Southern blot hybridization results showed that RecDNA-Abeta could replicate stably in N. benthamiana plants. PMID:18089755

  17. Naturally occurring compounds elicit HIV-1 replication in chronically infected promonocytic cells.

    PubMed

    Barquero, Andrea Alejandra; Dávola, María Eugenia; Riva, Diego Ariel; Mersich, Susana Esther; Alché, Laura Edith

    2014-01-01

    Since antiretroviral therapy suppresses but does not eradicate HIV-1 infection, methods to purge viral reservoirs are required. Many strategies involve the reactivation of chronically HIV infected cells to induce the expression of integrated viral genome. In this study, five bioactive compounds, the plant derivatives 1-cinnamoyl-3,11-dihydroxymeliacarpin (CDM), nordihydroguaiaretic acid (NDGA), and curcumin (Cur) and the synthetic stigmasterol analogs (22S,23S)-22,23-dihydroxystigmast-4-en-3-one (compound 1) and (22S,23S)-3 β -bromo-5 α ,22,23-trihydroxystigmastan-6-one (compound 2), were evaluated for their ability to elicit HIV replication in promonocytic (U1) and lymphocytic (H9+) HIV-1 chronically infected cells. The results revealed that natural compounds CDM, NDGA, and Cur were able to increase HIV-1 p24 antigen, determined by ELISA, only in latently infected promonocytic cells. CDM would reactivate HIV from latency by modulating the release of IL-6 and TNF- α , since the amount of both cytokines measured through ELISA significantly increased in U1 treated cells. Besides, NDGA increased ROS production, which might be related to the increase on p24 level observed in NDGA treated U1. These findings suggest that CDM, NDGA, and Cur might be candidates for further studies on latency-reversing therapeutics to eliminate latently HIV-1 reservoirs. PMID:24901006

  18. Using naturally occurring radionuclides to determine drinking water age in a community water system

    DOE PAGESBeta

    Waples, James T.; Bordewyk, Jason K.; Knesting, Kristina M.; Orlandini, Kent A.

    2015-07-22

    Drinking water quality in a community water system is closely linked to the age of water from initial treatment to time of delivery. However, water age is difficult to measure with conventional chemical tracers; particularly in stagnant water, where the relationship between disinfectant decay, microbial growth, and water age is poorly understood. Using radionuclides that were naturally present in source water, we found that measured activity ratios of 90Y/90Sr and 234Th/238U in discrete drinking water samples of known age accurately estimated water age up to 9 days old (σest: ± 3.8 h, P < 0.0001, r2 = 0.998, n =more » 11) and 25 days old (σest: ± 13.3 h, P < 0.0001, r2 = 0.996, n = 12), respectively. Moreover, 90Y-derived water ages in a community water system (6.8 × 104 m3 d–1 capacity) were generally consistent with water ages derived from an extended period simulation model. Radionuclides differ from conventional chemical tracers in that they are ubiquitous in distribution mains and connected premise plumbing. The ability to measure both water age and an analyte (e.g., chemical or microbe) in any water sample at any time allows for new insight into factors that control drinking water quality.« less

  19. Microbial interactions with naturally occurring hydrophobic sediments: Influence on sediment and associated contaminant mobility.

    PubMed

    Droppo, I G; Krishnappan, B G; Lawrence, J R

    2016-04-01

    The erosion, transport and fate of sediments and associated contaminants are known to be influenced by both particle characteristics and the flow dynamics imparted onto the sediment. The influential role of bitumen containing hydrophobic sediments and the microbial community on sediment dynamics are however less understood. This study links an experimental evaluation of sediment erosion with measured sediment-associated contaminant concentrations and microbial community analysis to provide an estimate of the potential for sediment to control the erosion, transport and fate of contaminants. Specifically the paper addresses the unique behaviour of hydrophobic sediments and the role that the microbial community associated with hydrophobic sediment may play in the transport of contaminated sediment. Results demonstrate that the hydrophobic cohesive sediment demonstrates unique transport and particle characteristics (poor settling and small floc size). Biofilms were observed to increase with consolidation/biostabilization times and generated a unique microbial consortium relative to the eroded flocs. Natural oil associated with the flocs appeared to be preferentially associated with microbial derived extracellular polymeric substances. While PAHs and naphthenic acid increased with increasing shear (indicative of increasing loads), they tended to decrease with consolidation/biostabilization (CB) time at similar shears suggesting a chemical and/or biological degradation. PAH and napthenic acid degrading microbes decreased with time as well, which may suggest that there was a reduced pool of PAHs and naphthenic acids available resulting in their die off. This study emphasizes the importance that any management strategies and operational assessments for the protection of human and aquatic health incorporate the sediment (suspended and bed sediment) and biological (biofilm) compartments and the energy dynamics within the system in order to better predict contaminant transport. PMID:26849315

  20. Effectiveness of mineral soil to adsorb the natural occurring radioactive material (norm), uranium and thorium

    NASA Astrophysics Data System (ADS)

    Amir, Muhammad Nur Iman; Ismail, Nurul Izzatiafifi; Wood, Ab. Khalik; Saat, Ahmad; Hamzah, Zaini

    2015-04-01

    A study has been performed on U-soil and Th-soil adsorption of three types of soil collected from Selangor State of Malaysia which are Saujana Putra, Bukit Changgang and Jenderam Hilir. In this study, natural radionuclide (U and Th) soil adsorption based on batch experiments with various initial concentrations of the radionuclide elements were carried out. Parameters that were set constant include pH at 5;amount of soil used was 5 g each, contact time was 24 hour and different initial concentration for each solution of U and Th which is 5 mg/L, 10 mg/L, 15 mg/L, 20 mg/L, 25 mg/L and 40 mg/L were used. The Kd values for each type of soil were determined in this batch experiments which was based on US-EPA method, in order to estimate adsorption capacity of the soil.The Kd values of Th found higher than Kd values of U for all of the soil samples, and the highest was found on the soil collected from Bukit Changgang. The soil clay content was one of factors to influence the adsorption of both U and Th from dilute initial solution. The U-soil and Th-soil adsorption process for all the soil samples studied are generally obeying unimolecular layer Langmuir isotherm model. From Langmuir isotherm, the maximum adsorption capacity for U was 0.393mg/g and for Th was 1.53 mg/g for the soil that was taken from Bukit Changgang. From the study, it suggested that the soil from Bukit Changgang applicable as potential enhanced barrier for site disposing waste containing U and Th.

  1. Original mechanism of failure initiation revealed through modelling of naturally occurring microstructures

    NASA Astrophysics Data System (ADS)

    Gorbatikh, Larissa; Lomov, Stepan V.; Verpoest, Ignaas

    2010-05-01

    Motivated to reveal original mechanisms of failure resistance, we developed a material model that encompasses most reoccurring microstructural features of natural composites. The interesting result of the work is a notion that material failure is governed by the quality of interactions between hierarchical levels in the material microstructure. With intelligent use of the structure, these interactions can be tuned to create a powerful synergetic effect on the material failure behaviour. For example, while exploring different mechanisms of failure initiation in composites with bimodal size reinforcements (an indirect way to model two levels of hierarchy simultaneously) we found that failure initiation could be shifted from stress concentration sites of the higher level to the lower level. One could say that the material behaviour became insensitive to the presence of reinforcements on the higher level—a phenomenon that is counterintuitive to what is commonly known. The new mechanism of failure initiation could only be activated in composites with a highly controlled structural organization—in the studied case, reinforcements of the lower level needed to establish lamellar pathways between reinforcements of the higher level. These pathways lead to formation of an intriguing network-like microstructure. Intelligent communication between reinforcements in such a network created the necessary synergy to change the failure initiation mechanism in a discontinuous fashion. Another finding was that by establishing such a network, tensile stresses near dangerous stress concentration sites were locally transformed into compressive stresses. Resemblance of the revealed mechanism to phenomena on the nano-scale was also discussed. In the course of this work a new method was developed to investigate interactions between reinforcements and their collective input into effective and local properties of a composite. The reinforcement phase was modelled with the use of rigid-line inhomogeneities.

  2. Effectiveness of mineral soil to adsorb the natural occurring radioactive material (norm), uranium and thorium

    SciTech Connect

    Amir, Muhammad Nur Iman; Ismail, Nurul Izzatiafifi; Wood, Ab. Khalik Saat, Ahmad; Hamzah, Zaini

    2015-04-29

    A study has been performed on U-soil and Th-soil adsorption of three types of soil collected from Selangor State of Malaysia which are Saujana Putra, Bukit Changgang and Jenderam Hilir. In this study, natural radionuclide (U and Th) soil adsorption based on batch experiments with various initial concentrations of the radionuclide elements were carried out. Parameters that were set constant include pH at 5;amount of soil used was 5 g each, contact time was 24 hour and different initial concentration for each solution of U and Th which is 5 mg/L, 10 mg/L, 15 mg/L, 20 mg/L, 25 mg/L and 40 mg/L were used. The K{sub d} values for each type of soil were determined in this batch experiments which was based on US-EPA method, in order to estimate adsorption capacity of the soil.The K{sub d} values of Th found higher than Kd values of U for all of the soil samples, and the highest was found on the soil collected from Bukit Changgang. The soil clay content was one of factors to influence the adsorption of both U and Th from dilute initial solution. The U-soil and Th-soil adsorption process for all the soil samples studied are generally obeying unimolecular layer Langmuir isotherm model. From Langmuir isotherm, the maximum adsorption capacity for U was 0.393mg/g and for Th was 1.53 mg/g for the soil that was taken from Bukit Changgang. From the study, it suggested that the soil from Bukit Changgang applicable as potential enhanced barrier for site disposing waste containing U and Th.

  3. Allelic polymorphism of GIGANTEA is responsible for naturally occurring variation in circadian period in Brassica rapa.

    PubMed

    Xie, Qiguang; Lou, Ping; Hermand, Victor; Aman, Rashid; Park, Hee Jin; Yun, Dae-Jin; Kim, Woe Yeon; Salmela, Matti Juhani; Ewers, Brent E; Weinig, Cynthia; Khan, Sarah L; Schaible, D Loring P; McClung, C Robertson

    2015-03-24

    GIGANTEA (GI) was originally identified by a late-flowering mutant in Arabidopsis, but subsequently has been shown to act in circadian period determination, light inhibition of hypocotyl elongation, and responses to multiple abiotic stresses, including tolerance to high salt and cold (freezing) temperature. Genetic mapping and analysis of families of heterogeneous inbred lines showed that natural variation in GI is responsible for a major quantitative trait locus in circadian period in Brassica rapa. We confirmed this conclusion by transgenic rescue of an Arabidopsis gi-201 loss of function mutant. The two B. rapa GI alleles each fully rescued the delayed flowering of Arabidopsis gi-201 but showed differential rescue of perturbations in red light inhibition of hypocotyl elongation and altered cold and salt tolerance. The B. rapa R500 GI allele, which failed to rescue the hypocotyl and abiotic stress phenotypes, disrupted circadian period determination in Arabidopsis. Analysis of chimeric B. rapa GI alleles identified the causal nucleotide polymorphism, which results in an amino acid substitution (S264A) between the two GI proteins. This polymorphism underlies variation in circadian period, cold and salt tolerance, and red light inhibition of hypocotyl elongation. Loss-of-function mutations of B. rapa GI confer delayed flowering, perturbed circadian rhythms in leaf movement, and increased freezing and increased salt tolerance, consistent with effects of similar mutations in Arabidopsis. Collectively, these data suggest that allelic variation of GI-and possibly of clock genes in general-offers an attractive target for molecular breeding for enhanced stress tolerance and potentially for improved crop yield. PMID:25775524

  4. Using naturally occurring radionuclides to determine drinking water age in a community water system

    SciTech Connect

    Waples, James T.; Bordewyk, Jason K.; Knesting, Kristina M.; Orlandini, Kent A.

    2015-07-22

    Drinking water quality in a community water system is closely linked to the age of water from initial treatment to time of delivery. However, water age is difficult to measure with conventional chemical tracers; particularly in stagnant water, where the relationship between disinfectant decay, microbial growth, and water age is poorly understood. Using radionuclides that were naturally present in source water, we found that measured activity ratios of 90Y/90Sr and 234Th/238U in discrete drinking water samples of known age accurately estimated water age up to 9 days old (σest: ± 3.8 h, P < 0.0001, r2 = 0.998, n = 11) and 25 days old (σest: ± 13.3 h, P < 0.0001, r2 = 0.996, n = 12), respectively. Moreover, 90Y-derived water ages in a community water system (6.8 × 104 m3 d–1 capacity) were generally consistent with water ages derived from an extended period simulation model. Radionuclides differ from conventional chemical tracers in that they are ubiquitous in distribution mains and connected premise plumbing. The ability to measure both water age and an analyte (e.g., chemical or microbe) in any water sample at any time allows for new insight into factors that control drinking water quality.

  5. Isotopic studies of rare gases in terrestrial samples and in natural nucleosynthesis

    SciTech Connect

    Reynolds, J.H.

    1988-08-01

    This project is concerned with research in rare gas mass spectrometry. The broad objective is to read the natural record that isotopes of the rare gases comprise as trace constituents of natural gases, rocks, and meteorites. In past years, these interests have led to the study of such diverse problems as the dating of rocks, the early chronology and isotopic structure of the solar system as revealed by extinct radioactivities, and the elemental and isotopic composition of trapped primordial rare gases in meteorites. In recent years, the project has focused progressively more on terrestrial problems.

  6. Naturally occurring and stress induced tubular structures from mammalian cells, a survival mechanism

    PubMed Central

    Wu, Yonnie; Laughlin, Richard C; Henry, David C; Krueger, Darryl E; Hudson, JoAn S; Kuan, Cheng-Yi; He, Jian; Reppert, Jason; Tomkins, Jeffrey P

    2007-01-01

    Background Tubular shaped mammalian cells in response to dehydration have not been previously reported. This may be due to the invisibility of these cells in aqueous solution, and because sugars and salts added to the cell culture for manipulation of the osmotic conditions inhibit transformation of normal cells into tubular shaped structures. Results We report the transformation of normal spherical mammalian cells into tubular shaped structures in response to stress. We have termed these transformed structures 'straw cells' which we have associated with a variety of human tissue types, including fresh, post mortem and frozen lung, liver, skin, and heart. We have also documented the presence of straw cells in bovine brain and prostate tissues of mice. The number of straw cells in heart, lung tissues, and collapsed straw cells in urine increases with the age of the mammal. Straw cells were also reproduced in vitro from human cancer cells (THP1, CACO2, and MCF7) and mouse stem cells (D1 and adipose D1) by dehydrating cultured cells. The tubular center of the straw cells is much smaller than the original cell; houses condensed organelles and have filamentous extensions that are covered with microscopic hair-like structures and circular openings. When rehydrated, the filaments uptake water rapidly. The straw cell walls, have a range of 120 nm to 200 nm and are composed of sulfated-glucose polymers and glycosylated acidic proteins. The transformation from normal cell to straw cells takes 5 to 8 hr in open-air. This process is characterized by an increase in metabolic activity. When rehydrated, the straw cells regain their normal spherical shape and begin to divide in 10 to 15 days. Like various types of microbial spores, straw cells are resistant to harsh environmental conditions such as UV-C radiation. Conclusion Straw cells are specialized cellular structures and not artifacts from spontaneous polymerization, which are generated in response to stress conditions, like dehydration. The disintegrative, mobile, disruptive and ubiquitous nature of straw cells makes this a possible physiological process that may be involved in human health, longevity, and various types of diseases such as cancer. PMID:17705822

  7. Nuclear genomic control of naturally occurring variation in mitochondrial function in Drosophila melanogaster

    PubMed Central

    2012-01-01

    Background Mitochondria are organelles found in nearly all eukaryotic cells that play a crucial role in cellular survival and function. Mitochondrial function is under the control of nuclear and mitochondrial genomes. While the latter has been the focus of most genetic research, we remain largely ignorant about the nuclear-encoded genomic control of inter-individual variability in mitochondrial function. Here, we used Drosophila melanogaster as our model organism to address this question. Results We quantified mitochondrial state 3 and state 4 respiration rates and P:O ratio in mitochondria isolated from the thoraces of 40 sequenced inbred lines of the Drosophila Genetic Reference Panel. We found significant within-population genetic variability for all mitochondrial traits. Hence, we performed genome-wide association mapping and identified 141 single nucleotide polymorphisms (SNPs) associated with differences in mitochondrial respiration and efficiency (P ≤1 × 10-5). Gene-centered regression models showed that 2–3 SNPs can explain 31, 13, and 18% of the phenotypic variation in state 3, state 4, and P:O ratio, respectively. Most of the genes tagged by the SNPs are involved in organ development, second messenger-mediated signaling pathways, and cytoskeleton remodeling. One of these genes, sallimus (sls), encodes a component of the muscle sarcomere. We confirmed the direct effect of sls on mitochondrial respiration using two viable mutants and their coisogenic wild-type strain. Furthermore, correlation network analysis revealed that sls functions as a transcriptional hub in a co-regulated module associated with mitochondrial respiration and is connected to CG7834, which is predicted to encode a protein with mitochondrial electron transfer flavoprotein activity. This latter finding was also verified in the sls mutants. Conclusions Our results provide novel insights into the genetic factors regulating natural variation in mitochondrial function in D. melanogaster. The integrative genomic approach used in our study allowed us to identify sls as a novel hub gene responsible for the regulation of mitochondrial respiration in muscle sarcomere and to provide evidence that sls might act via the electron transfer flavoprotein/ubiquinone oxidoreductase complex. PMID:23171078

  8. Tartan Turf on trial. A comparison of intercollegiate football injuries occurring on natural grass and Tartan Turf.

    PubMed

    Keene, J S; Narechania, R G; Sachtjen, K M; Clancy, W G

    1980-01-01

    We retro- and prospectively compared collegiate football injuries that occurred on the grass and Tartan Turf (3M Company, St. Paul, Minnesota) fields at the University of Wisconsin. Retrospective injury data were obtained from questionnaires returned by 235 of 450 athletes that competed from 1960 to 1973. Prospective injury data were obtained by examination of athletes injured from 1975 through 1977. Although the number of injuries occurring on each playing surface were not significantly different, the type and severity of injuries were significantly different. We found that significantly more serious sprains and torn ligaments occurred on grass than occurred on Tartan Turf. There were significantly more scrapes (minor injuries) on the Tartan Turf than on the grass. We conclude that we may be prematurely returning to natural grass playing surfaces, and--to the detriment of the athlete--ending production of one synthetic turf that helped reduce major injuries. PMID:7356798

  9. Rapidly Assessing Changes in Bone Mineral Balance Using Natural Stable Calcium Isotopes

    NASA Technical Reports Server (NTRS)

    Morgan, J. L. L.; Gordon, G. W.; Romaniello, S. J.; Skulan, J. L.; Smith, S. M.; Anbar, A. D.

    2011-01-01

    We demonstrate that variations in the Ca isotope ratios in urine rapidly and quantitatively reflect changes in bone mineral balance. This variation occurs because bone formation depletes soft tissue of light Ca isotopes, while bone resorption releases that isotopically light Ca back into soft tissue. In a study of 12 individuals confined to bed rest, a condition known to induce bone resorption, we show that Ca isotope ratios shift in a direction consistent with net bone loss after just 7 days, long before detectible changes in bone density occur. Consistent with this interpretation, the Ca isotope variations track changes observed in N-teleopeptide, a bone resorption biomarker, while bone-specific alkaline phosphatase, a bone formation biomarker, is unchanged. Ca isotopes can in principle be used to quantify net changes in bone mass. Ca isotopes indicate an average loss of 0.62 +/- 0.16 % in bone mass over the course of this 30-day study. The Ca isotope technique should accelerate the pace of discovery of new treatments for bone disease and provide novel insights into the dynamics of bone metabolism.

  10. Using Natural Stable Calcium Isotopes to Rapidly Assess Changes in Bone Mineral Balance Using a Bed Rest Model to Induce Bone Loss

    NASA Technical Reports Server (NTRS)

    Morgan, J. L. L.; Skulan, J. L.; Gordon, G. E.; Smith, Scott M.; Romaniello, S. J.; Anbar, A. D.

    2012-01-01

    Metabolic bone diseases like osteoporosis result from the disruption of normal bone mineral balance (BMB) resulting in bone loss. During spaceflight astronauts lose substantial bone. Bed rest provides an analog to simulate some of the effects of spaceflight; including bone and calcium loss and provides the opportunity to evaluate new methods to monitor BMB in healthy individuals undergoing environmentally induced-bone loss. Previous research showed that natural variations in the Ca isotope ratio occur because bone formation depletes soft tissue of light Ca isotopes while bone resorption releases that isotopically light Ca back into soft tissue (Skulan et al, 2007). Using a bed rest model, we demonstrate that the Ca isotope ratio of urine shifts in a direction consistent with bone loss after just 7 days of bed rest, long before detectable changes in bone mineral density (BMD) occur. The Ca isotope variations tracks changes observed in urinary N-teleopeptide, a bone resorption biomarker. Bone specific alkaline phosphatase, a bone formation biomarker, is unchanged. The established relationship between Ca isotopes and BMB can be used to quantitatively translate the changes in the Ca isotope ratio to changes in BMD using a simple mathematical model. This model predicts that subjects lost 0.25 0.07% ( SD) of their bone mass from day 7 to day 30 of bed rest. Given the rapid signal observed using Ca isotope measurements and the potential to quantitatively assess bone loss; this technique is well suited to study the short-term dynamics of bone metabolism.

  11. Magnesium isotope fractionation by chemical diffusion in natural settings and in laboratory analogues

    NASA Astrophysics Data System (ADS)

    Chopra, Rahul; Richter, Frank M.; Bruce Watson, E.; Scullard, Christian R.

    2012-07-01

    Laboratory experiments are used to document isotopic fractionation of magnesium by chemical diffusion in a silicate melt and the results compared to the magnesium isotopic composition across contacts between igneous rocks of different composition in natural settings. The natural samples are from transects from felsic to mafic rocks at Vinal Cove in the Vinalhaven Intrusive Complex, Maine and from the Aztec Wash pluton in Nevada. Two laboratory diffusion couples made by juxtaposing melts made from powders of the felsic and mafic compositions sampled at Vinal Cove were annealed at about 1500 °C for 22.5 and 10 h, respectively. The transport of magnesium in the diffusion couples resulted in easily measured magnesium isotopic fractionations at the interface (δ26Mg∼1.5‰). These isotopic fractionations provide a distinctive isotopic “fingerprint” that we use to determine whether chemical gradients in natural settings where melts of different composition were juxtaposed were due to chemical diffusion. The magnesium isotopic fractionation along one profile at Vinal Cove is exactly what one would expect based on the fractionations found in the laboratory experiments. This is an important result in that it shows that the isotope fractionation by chemical diffusion found in highly controlled laboratory experiments can be found in a natural setting. This correspondence implies that chemical diffusion was the dominant process responsible for the transport of magnesium across this particular contact at Vinal Cove. A second Vinal Cove profile has a very similar gradient in magnesium concentration but with significantly less magnesium isotopic fractionation than expected. This suggests that mass transport at this location was only partly by diffusion and that some other mass transport mechanism such as mechanical mixing must have also played a role. The magnesium isotopic composition of samples from Aztec Wash shows no resolvable isotopic fractionation across the contact between the mafic and felsic rocks. The different degrees of magnesium isotopic fractionation associated with otherwise similar composition gradients in natural settings show that kinetic isotope fractionations provide a key discriminator for establishing whether or not molecular diffusion was the process responsible for an observed elemental gradient. In the one case of a contact at Vinal Cove where we are confident that the magnesium elemental and isotopic gradients were produced by diffusion, we deduced a cooling rate of about 1.5 °C per day.

  12. Measurement of natural carbon isotopic composition of acetone in human urine.

    PubMed

    Yamada, Keita; Ohishi, Kazuki; Gilbert, Alexis; Akasaka, Mai; Yoshida, Naohiro; Yoshimura, Ryoko

    2016-02-01

    The natural carbon isotopic composition of acetone in urine was measured in healthy subjects using gas chromatography-combustion-isotope ratio mass spectrometry combined with headspace solid-phase microextraction (HS-SPME-GC-C-IRMS). Before applying the technique to a urine sample, we optimized the measurement conditions of HS-SPME-GC-C-IRMS using aqueous solutions of commercial acetone reagents. The optimization enabled us to determine the carbon isotopic compositions within 0.2? of precision and 0.3 of error using 0.05 or 0.2mL of aqueous solutions with acetone concentrations of 0.3-121mg/L. For several days, we monitored the carbon isotopic compositions and concentrations of acetone in urine from three subjects who lived a daily life with no restrictions. We also monitored one subject for 3days including a fasting period of 24h. These results suggest that changes in the availability of glucose in the liver are reflected in changes in the carbon isotopic compositions of urine acetone. Results demonstrate that carbon isotopic measurement of metabolites in human biological samples at natural abundance levels has great potential as a tool for detecting metabolic changes caused by changes in physiological states and disease. Graphical abstract The natural carbon isotopic composition of acetone in urine can be determined using HS-SPME-GCC-IRMS and can provide information on changes in the availability of glucose in the liver. PMID:26718914

  13. Laccase?catalysed oxidations of naturally occurring phenols: from in vivo biosynthetic pathways to green synthetic applications

    PubMed Central

    Jeon, Jong?Rok; Baldrian, Petr; Murugesan, Kumarasamy; Chang, Yoon?Seok

    2012-01-01

    Summary Laccases are oxidases that contain several copper atoms, and catalyse single?electron oxidations of phenolic compounds with concomitant reduction of oxygen to water. The enzymes are particularly widespread in ligninolytic basidiomycetes, but also occur in certain prokaryotes, insects and plants. Depending on the species, laccases are involved in various biosynthetic processes contributing to carbon recycling in land ecosystems and the morphogenesis of biomatrices, wherein low?molecular?weight naturally occurring phenols serve as key enzyme substrates. Studies of these in vivo synthetic pathways have afforded new insights into fungal laccase applicability in green synthetic chemistry. Thus, we here review fungal laccase?catalysed oxidations of naturally occurring phenols that are particularly relevant to the synthesis of fine organic chemicals, and we discuss how the discovered synthetic strategies mimic laccase?involved in vivo pathways, thus enhancing the green nature of such reactions. Laccase?catalysed in vivo processes yield several types of biopolymers, including those of cuticles, lignin, polyflavonoids, humus and the melanin pigments, using natural mono? or poly?phenols as building blocks. The in vivo synthetic pathways involve either phenoxyl radical?mediated coupling or cross?linking reactions, and can be adapted to the design of in vitro oxidative processes involving fungal laccases in organic synthesis; the laccase substrates and the synthetic mechanisms reflect in vivo processes. Notably, such in vitro synthetic pathways can also reproduce physicochemical properties (e.g. those of chromophores, and radical?scavenging, hydration and antimicrobial activities) found in natural biomaterials. Careful study of laccase?associated in vivo metabolic pathways has been rewarded by the discovery of novel green applications for fungal laccases. This review comprehensively summarizes the available data on laccase?catalysed biosynthetic pathways and associated applications in fine chemical syntheses. PMID:21791030

  14. APPLICATIONS OF ENVIRONMENTAL ISOTOPES FOR WATERSHED INVESTIGATIONS

    EPA Science Inventory

    Environmental isotopes include naturally-occurring nuclides that can be applied as tracers within watersheds (Sidle, 1998). Recent advances in mass spectroscopy may supplant many traditional and costly hydrometric techniques. It is now possible, for example, to utilize isotopes a...

  15. Prediction of rodent carcinogenic potential of naturally occurring chemicals in the human diet using high-throughput QSAR predictive modeling

    SciTech Connect

    Valerio, Luis G. . E-mail: luis.valerio@FDA.HHS.gov; Arvidson, Kirk B.; Chanderbhan, Ronald F.; Contrera, Joseph F.

    2007-07-01

    Consistent with the U.S. Food and Drug Administration (FDA) Critical Path Initiative, predictive toxicology software programs employing quantitative structure-activity relationship (QSAR) models are currently under evaluation for regulatory risk assessment and scientific decision support for highly sensitive endpoints such as carcinogenicity, mutagenicity and reproductive toxicity. At the FDA's Center for Food Safety and Applied Nutrition's Office of Food Additive Safety and the Center for Drug Evaluation and Research's Informatics and Computational Safety Analysis Staff (ICSAS), the use of computational SAR tools for both qualitative and quantitative risk assessment applications are being developed and evaluated. One tool of current interest is MDL-QSAR predictive discriminant analysis modeling of rodent carcinogenicity, which has been previously evaluated for pharmaceutical applications by the FDA ICSAS. The study described in this paper aims to evaluate the utility of this software to estimate the carcinogenic potential of small, organic, naturally occurring chemicals found in the human diet. In addition, a group of 19 known synthetic dietary constituents that were positive in rodent carcinogenicity studies served as a control group. In the test group of naturally occurring chemicals, 101 were found to be suitable for predictive modeling using this software's discriminant analysis modeling approach. Predictions performed on these compounds were compared to published experimental evidence of each compound's carcinogenic potential. Experimental evidence included relevant toxicological studies such as rodent cancer bioassays, rodent anti-carcinogenicity studies, genotoxic studies, and the presence of chemical structural alerts. Statistical indices of predictive performance were calculated to assess the utility of the predictive modeling method. Results revealed good predictive performance using this software's rodent carcinogenicity module of over 1200 chemicals, comprised primarily of pharmaceutical, industrial and some natural products developed under an FDA-MDL cooperative research and development agreement (CRADA). The predictive performance for this group of dietary natural products and the control group was 97% sensitivity and 80% concordance. Specificity was marginal at 53%. This study finds that the in silico QSAR analysis employing this software's rodent carcinogenicity database is capable of identifying the rodent carcinogenic potential of naturally occurring organic molecules found in the human diet with a high degree of sensitivity. It is the first study to demonstrate successful QSAR predictive modeling of naturally occurring carcinogens found in the human diet using an external validation test. Further test validation of this software and expansion of the training data set for dietary chemicals will help to support the future use of such QSAR methods for screening and prioritizing the risk of dietary chemicals when actual animal data are inadequate, equivocal, or absent.

  16. MNA for Chlorinated Solvents and Fuel Oxygenates: Why It Occurs, How It Evolved, and Using Stable Carbon Isotopes to Predict Plume Behavior

    EPA Science Inventory

    The organisms that degrade MtBE under anaerobic conditions are evolved to acquire energy for growth by using molecular hydrogen and carbonate ion to cleave methyl ether bonds. Methyl ether bonds are common in nature and the bond also occurs in MTBE. MTBE in contaminated ground...

  17. MNA of Chlorinated Solvents and Fuel Oxygenates: Why it occurs, how it evolved, and using stable carbon isotopes to predict plume behavior

    EPA Science Inventory

    The organisms that degrade MTBE under anaerobic conditions are evolved to acquire energy for growth by using molecular hydrogen and carbonate ion to cleave methyl ether bonds. Methyl ether bonds are common in nature and the bond also occurs in MTBE. MTBE in contaminated ground...

  18. Naturally Occurring Asbestos in Washington State: Swift Creek at the Intersection of Science, Law, and Risk Perception

    NASA Astrophysics Data System (ADS)

    Melious, J. O.

    2012-12-01

    In the northwestern corner of Washington state, a large landslide on Sumas Mountain deposits more than 100,000 cubic yards of soil containing asbestos fibers and heavy metals into Swift Creek every year. Engineers predict that asbestos-laden soils will slide into Swift Creek for at least the next 400 years. Swift Creek joins the Sumas River, which crosses the border into Canada, serving as an international delivery system for asbestos-laden soils. When the rivers flood, as happens regularly, they deliver asbestos into field, yards, and basements. The tools available to address the Swift Creek situation are at odds with the scope and nature of the problem. Asbestos regulation primarily addresses occupational settings, where exposures can be estimated. Hazardous waste regulation primarily addresses liability for abandoned waste products from human activities. Health and environmental issues relating to naturally occurring asbestos (NOA) are fundamentally different from either regulatory scheme. Liability is not a logical lever for a naturally occurring substance, the existence of which is nobody's fault, and exposures to NOA in the environment do not necessarily resemble occupational exposures. The gaps and flaws in the legal regime exacerbate the uncertainties created by uncertainties in the science. Once it is assumed that no level of exposure is safe, legal requirements adopted in very different contexts foreclose the options for addressing the Swift Creek problem. This presentation will outline the applicable laws and how they intersect with issues of risk perception, uncertainty and politics in efforts to address the Swift Creek NOA site.

  19. Naturally Occurring Radionuclides of Ash Produced by Coal Combustion. The Case of the Kardia Mine in Northern Greece

    SciTech Connect

    Fotakis, M.; Tsikritzis, L.; Tzimkas, N.; Kolovos, N.; Tsikritzi, R.

    2008-08-07

    West Macedonia Lignite Center (WMLC), located in Northwest Greece, releases into the atmosphere about 21,400 tons/year of fly ash through the stacks of four coal fired plants. The lignite ash contains naturally occurring radionuclides, which are deposited on the WMLC basin. This work investigates the natural radioactivity of twenty six ash samples, laboratory produced from combustion of lignite, which was sampled perpendicularly to the benches of the Kardia mine. The concentrations of radionuclides {sup 40}K, {sup 235}U, {sup 238}U, {sup 226}Ra, {sup 228}Ra and {sup 232}Th, were measured spectroscopically and found round one order of magnitude as high as those of lignite. Subsequently the Radionuclide Partitioning Coefficients of radionuclides were calculated and it was found that they are higher for {sup 232}Th, {sup 228}Ra and {sup 40}K, because the latter have closer affinity with the inorganic matrix of lignite. During combustion up to one third of the naturally occurring radioisotopes escape from the solid phase into the flue gases. With comparison to relative global data, the investigated ash has been found to have relatively high radioactivity, but the emissions of the WMLC radionuclides contribute only 0.03% to the mean annual absorbed dose.

  20. Natural gamma radiation from long-lived actinide isotopes

    SciTech Connect

    Dupree, S.A.; Sanger, H.M.

    1987-06-01

    The purpose of this report is to describe a method, developed at Sandia National Laboratories, for calculating volumetric, unshielded, gamma radiation source spectra with arbitrary energy group structures from essentially arbitrary mixtures of actinide isotopes. The computer code and data base are combined as INRAD. These spectra can be used to describe the source for gamma radiation transport codes. Coupled with this source routine is a special version of the one-dimensional, discrete ordinates, radiation transport code XSDRN that uses the spectrum generating routine to define sources in an appropriate energy group structure. 15 refs., 34 figs., 10 tabs.

  1. Water quality in the vicinity of Mosquito Creek Lake, Trumbull County, Ohio, in relation to the chemistry of locally occurring oil, natural gas, and brine

    USGS Publications Warehouse

    Barton, G.J.; Burruss, R.C.; Ryder, R.T.

    1998-01-01

    Environmental samples collected in the Mosquito Creek Lake area were used to characterize water quality in relation to the chemistry of locally occurring oil, natural gas, and brine and to establish baseline water quality. Mosquito Creek Lake (a manmade reservoir) and the shallow bedrock aquifers near the lake are major sources of potable water in central Trumbull County. The city of Warren relies on the lake as a sole source of potable water. Some of the lake bottom may be in direct hydraulic connection with the underlying aquifers. The city of Cortland, along the southeastern shore of the lake, relies on the Cussewago Sandstone aquifer as a sole source of potable water. This aquifer subcrops beneath the glacio-fluvial sediments that underlie the lake. Nearly all residential homes around the lake, with the exception of homes in the city of Cortland, rely on domestic supply wells as a source of potable water. Oil and natural gas exploration and production have been ongoing in the Mosquito Creek Lakearea since the discovery of the historic Mecca Oil Pool in the Mississippian Berea and Cussewago Sandstones in 1860. Since the late 1970' s, the major drilling objective and zone of production is the Lower Silurian Clinton sandstone. The oil and natural gas resources of the Mosquito Creek Lake area, including reservoir pressure, production history, and engineering and abandonment practices are described in this report. The chemical and isotopic characteristics of the historic Mecca oil and natural gas are very different than those of the Clinton sandstone oil and natural gas. Gas chromatograms show that Mecca oil samples are extensively altered by biodegradation, whereas Clinton sandstone oils are not. Extensive alteration of Mecca oil is consistent with their occurrence at very shallow depths (less than 100 ft below land surface) where microbial activity can affect their composition. Also, the carbon-isotope composition of dissolved methane gas from Berea and Cussewago Sandstone water samples indicates that the gas is microbially generated, whereas the Clinton sandstone gases are thermogenically generated. Methane gas, in addition to crude oil, occurs naturally in the shallow Berea and Cussewago Sandstone aquifers in the Mosquito Creek Lake area and concentrations of dissolved methane are significant in the city of Cortland public-supply wells and in the domestic-supply wells near the southern shore of the lake. Water associated with oil and gas in the Clinton sandstone is a brine with high concentrations of chloride. Water from the Berea and Cussewago Sandstones, however, is fresh and potable. The contrasting geochemical characteristics are important for addressing water-quality issues that relate to oil and natural gas development in the Mosquito Creek area. A reexamination of the geologic framework and results of a subsurface-gas survey show that crude oil in the historic Mecca Oil Pool probably does not seep into Mosquito Creek Lake. Environmental samples show no evidence of any measurable release of oil, gas, or brine from the deeper Clinton sandstone oil and gas wells to the shallow aquifers, the lake, or lake tributaries. Brine is not associated with the hydrocarbons in the shallow Berea-Cussewago aquifer system and therefore cannot be a source of brine contamination. A mixing diagram constructed for dissolved bromide and chloride in surface water and water-supply wells shows no demonstrable mixing of these water resources with brine from the Clinton sandstone. There is some notable salinity in surface waters; however, the water is bromide poor, and a mixing diagram indicates that some local ground waters are influenced by halite solutions, presumably derived from leaching of road salt or from septic effluent.

  2. Ultrastructural aspects of naturally occurring wound in the tunic of two ascidians: Ciona intestinalis and Styela plicata (Tunicata).

    PubMed

    Di Bella, Maria Antonietta; Carbone, Maria Carmela; De Leo, Giacomo

    2015-02-01

    Efficient wound healing is essential for all animals from insects to mammals. Ciona intestinalis and Styela plicata are solitary ascidians belonging to urochordates, a subphylum that occupies a key phylogenetic position as it includes the closest relative to vertebrates. Urochordate first physical barrier against invaders is the tunic, an extracellular matrix that is constantly exposed to all kinds of insults. Thus, when damage occurs, an innate immune response is triggered to eliminate impaired tissue and potentially pathogenic microbes, and restore tissue functionality. Ultrastructural aspects of the tunic in the wound healing process of two ascidians are described. In the injured areas, we evidenced thinning of the tunic and areas of low fibre density, dense intratunic bacterial and protozoan population, and inflammatory aspects such as the increase in tunic cells, their aggregates, and phagocytosis. This is the first report on tunic physical wounding occurring in the natural habitat. PMID:25437850

  3. 2-Deoxyadenosine triphosphate restores the contractile function of cardiac myofibril from adult dogs with naturally occurring dilated cardiomyopathy.

    PubMed

    Cheng, Yuanhua; Hogarth, Kaley A; O'Sullivan, M Lynne; Regnier, Michael; Pyle, W Glen

    2016-01-01

    Dilated cardiomyopathy (DCM) is a major type of heart failure resulting from loss of systolic function. Naturally occurring canine DCM is a widely accepted experimental paradigm for studying human DCM. 2-Deoxyadenosine triphosphate (dATP) can be used by myosin and is a superior energy substrate over ATP for cross-bridge formation and increased systolic function. The objective of this study was to evaluate the beneficial effect of dATP on contractile function of cardiac myofibrils from dogs with naturally occurring DCM. We measured actomyosin NTPase activity and contraction/relaxation properties of isolated myofibrils from nonfailing (NF) and DCM canine hearts. NTPase assays indicated replacement of ATP with dATP significantly increased myofilament activity in both NF and DCM samples. dATP significantly improved maximal tension of DCM myofibrils to the NF sample level. dATP also restored Ca(2+) sensitivity of tension that was reduced in DCM samples. Similarly, dATP increased the kinetics of contractile activation (kACT), with no impact on the rate of cross-bridge tension redevelopment (kTR). Thus, the activation kinetics (kACT/kTR) that were reduced in DCM samples were restored for dATP to NF sample levels. dATP had little effect on relaxation. The rate of early slow-phase relaxation was slightly reduced with dATP, but its duration was not, nor was the fast-phase relaxation or times to 50 and 90% relaxation. Our findings suggest that myosin utilization of dATP improves cardiac myofibril contractile properties of naturally occurring DCM canine samples, restoring them to NF levels, without compromising relaxation. This suggests elevation of cardiac dATP is a promising approach for the treatment of DCM. PMID:26497964

  4. Distribution of the PBC-specific- (M2) and the naturally-occurring mitochondrial antigen- (NOMAg) systems in plants.

    PubMed Central

    Lang, P; Klein, R; Becker, E W; Berg, P A

    1992-01-01

    In previous studies it was demonstrated that antibodies in sera from patients with primary biliary cirrhosis (PBC) and their relatives can recognize two different antigen systems in the ATPase fraction prepared from beef heart mitochondria, namely the PBC-related M2- and the naturally occurring mitochondrial antigen (NOMAg)-related epitopes. Since separation of these two antigen systems could not be achieved using mammalian mitochondria, mitochondria from a wide spectrum of plants were analysed with respect to the presence of mitochondrial antigens. Mitochondria from 29 species of plants were prepared and tested by ELISA and Western blot using marker sera from patients with PBC reacting in the Western blot with M2a,b,c,d (alpha-ketoacid-dehydrogenase complex) and NOMAg-specific sera recognizing the three major epitopes epsilon, zeta, and eta at 65, 61 and 58 kD. Naturally occurring mitochondrial antibody (NOMA)-positive marker sera reacted in the ELISA with mitochondria from all plants, and the zeta/eta positive sera gave also a positive reaction at 61/58 kD in the Western blot while the epsilon epitope could not be visualized by this method. In contrast, the M2 antigen was detected preferentially in lower plants such as algae, fungi, and ferns. Analysing these data with respect to the evolution of proteins one would have to assume that the M2 antigen was lost in most higher plants or underwent some structural alterations. Furthermore, considering the fact that the M2- and the NOMAg-related epitopes could be only partially separated, i.e. there were no plant mitochondria showing only M2 but no NOMAg, one could speculate that anti-M2 antibodies are derived from the pool of naturally occurring antibodies. Images Fig. 2 PMID:1281057

  5. Nature of the Volume Isotope Effect in Ice.

    PubMed

    Umemoto, Koichiro; Sugimura, Emiko; de Gironcoli, Stefano; Nakajima, Yoichi; Hirose, Kei; Ohishi, Yasuo; Wentzcovitch, Renata M

    2015-10-23

    The substitution of hydrogen (H) by deuterium (D) in ice Ih and in its H-ordered version, ice XI, produces an anomalous form of volume isotope effect (VIE), i.e., volume expansion. This VIE contrasts with the normal VIE (volume contraction) predicted in ice-VIII and in its H-disordered form, ice VII. Here we investigate the VIE in ice XI and in ice VIII using first principles quasiharmonic calculations. We conclude that normal and anomalous VIEs can be produced in ice VIII and ice XI in sequence by application of pressure (ice XI starting at negative pressures) followed by a third type-anomalous VIE with zero-point volume contraction. The latter should also contribute to the isotope effect in the ice VII ? ice X transition. The predicted change between normal and anomalous VIE in ice VIII at 14.3GPa and 300K is well reproduced experimentally in ice VII using x-ray diffraction measurements. The present discussion of the VIE is general, and conclusions should be applicable to other solid phases of H_{2}O, possibly to liquid water under pressure, and to other H-bonded materials. PMID:26551113

  6. Positive Selection of Natural Poly-Reactive B Cells in the Periphery Occurs Independent of Heavy Chain Allelic Inclusion

    PubMed Central

    Xing, Ying; Ji, Qiuhe; Lin, Ying; Fu, Meng; Gao, Jixin; Zhang, Ping; Hu, Xingbin; Feng, Lei; Liu, Yufeng; Han, Hua; Li, Wei

    2015-01-01

    Natural autoreactive B cells are important mediators of autoimmune diseases. Receptor editing is known to play an important role in both central and peripheral B cell tolerance. However, the role of allelic inclusion in the development of natural autoreactive B cells is not clear. Previously, we generated ? chain (TgVH3B4I) and ?/? chains (TgVH/L3B4) transgenic mice using transgene derived from the 3B4 hybridoma, which produce poly-reactive natural autoantibodies. In this study, we demonstrate that a considerable population of B cells edited their B cells receptors (BCRs) via light chain or heavy chain allelic inclusion during their development in TgVH3B4I mice. Additionally, allelic inclusion occurred more frequently in the periphery and promoted the differentiation of B cells into marginal zone or B-1a cells in TgVH3B4I mice. B cells from TgVH/L3B4 mice expressing the intact transgenic 3B4 BCR without receptor editing secreted poly-reactive 3B4 antibody. Interestingly, however, B cell that underwent allelic inclusion in TgVH3B4I mice also produced poly-reactive autoantibodies in vivo and in vitro. Our findings suggest that receptor editing plays a minor role in the positive selection of B cells expressing natural poly-reactive BCRs, which can be positively selected through heavy chain allelic inclusion to retain their poly-reactivity in the periphery. PMID:25993514

  7. Nitrogen-isotope analysis of groundwater nitrate in carbonate aquifers: Natural sources versus human pollution

    NASA Astrophysics Data System (ADS)

    Kreitler, Charles W.; Browning, Lawrence A.

    1983-02-01

    Results of nitrogen-isotope analyses of nitrate in the waters of the Cretaceous Edwards aquifer in Texas, U.S.A., indicate that the source of the nitrate is naturally-occurring nitrogen compounds in the recharge streams. In contrast, nitrogen isotopes of nitrate in the fresh waters of the Pleistocene Ironshore Formation on Grand Cayman Island, West Indies, indicate that human wastes are the source of the nitrate. The Cretaceous Edwards Limestone is a prolific aquifer that produces principally from fracture porosity along the Balcones Fault Zone. Recharge is primarily by streams crossing the fault zone. Rainfall is ˜ 70 cm yr. -1, and the water table is generally deeper than 30 m below land surface. The δ15 N of 73 samples of nitrate from Edwards waters ranged from + 1.9 to + 10‰ with an average of + 6.2‰. This δ15 N range is within the range of nitrate in surface water in the recharge streams ( δ 15N range = + 1 to + 8.3‰ ) and within the range of nitrate in surface water from the Colorado River, Texas, ( δ 15N range = + 1 to + 11‰ ). No sample was found to be enriched in 15N, which would suggest the presence of nitrate from animal waste ( δ 15N range = + 10 to + 22‰ ). The Ironshore Formation contains a small freshwater lens that is recharged entirely by percolation through the soil. Average rainfall is 165 cm yr. -1, and the water table is within 3 m of land surface. The δ15 N of four nitrate samples from water samples of the Ironshore Formation ranged from + 18 to + 23.9‰, which indicates a cesspool/septictank source of the nitrate. Limestone aquifers in humid environments that are recharged by percolation through the soil appear to be more susceptible to contamination by septic tanks than are aquifers in subhumid environments that feature thick unsaturated sections and are recharged by streams.

  8. Rapidly assessing changes in bone mineral balance using natural stable calcium isotopes

    PubMed Central

    Morgan, Jennifer L. L.; Skulan, Joseph L.; Gordon, Gwyneth W.; Romaniello, Stephen J.; Smith, Scott M.; Anbar, Ariel D.

    2012-01-01

    The ability to rapidly detect changes in bone mineral balance (BMB) would be of great value in the early diagnosis and evaluation of therapies for metabolic bone diseases such as osteoporosis and some cancers. However, measurements of BMB are hampered by difficulties with using biochemical markers to quantify the relative rates of bone resorption and formation and the need to wait months to years for altered BMB to produce changes in bone mineral density large enough to resolve by X-ray densitometry. We show here that, in humans, the natural abundances of Ca isotopes in urine change rapidly in response to changes in BMB. In a bed rest experiment, use of high-precision isotope ratio MS allowed the onset of bone loss to be detected in Ca isotope data after about 1 wk, long before bone mineral density has changed enough to be detectable with densitometry. The physiological basis of the relationship between Ca isotopes and BMB is sufficiently understood to allow quantitative translation of changes in Ca isotope abundances to changes in bone mineral density using a simple model. The rate of change of bone mineral density inferred from Ca isotopes is consistent with the rate observed by densitometry in long-term bed rest studies. Ca isotopic analysis provides a powerful way to monitor bone loss, potentially making it possible to diagnose metabolic bone disease and track the impact of treatments more effectively than is currently possible. PMID:22652567

  9. Upper limits for the existence of long-lived isotopes of roentgenium in natural gold

    NASA Astrophysics Data System (ADS)

    Dellinger, F.; Kutschera, W.; Forstner, O.; Golser, R.; Priller, A.; Steier, P.; Wallner, A.; Winkler, G.

    2011-01-01

    A sensitive search for isotopes of a superheavy element (SHE) in natural gold materials has been performed with accelerator mass spectrometry at the Vienna Environmental Research Accelerator, which is based on a 3-MV tandem accelerator. Because the most likely SHE in gold is roentgenium (Rg, Z = 111), the search concentrated on Rg isotopes. Two different mass regions were explored: (i) For the neutron-deficient isotopes Rg261 and Rg265, abundance limits in gold of 310-16 were reached (no events observed). This is in stark contrast to the findings of Marinov [Int. J. Mod. Phys. EIMPEER0218-301310.1142/S021830130901280X 18, 621 (2009)], who reported positive identification of these isotopes with inductively coupled plasma sector field mass spectrometry in the (1-10)10-10 abundance range. (ii) Theoretical models of SHEs predict a region of increased stability around the proton and neutron shell closures of Z = 114 and N = 184. We therefore investigated eight heavy Rg isotopes, ARg, A = 289, 290, 291, 292, 293, 294, 295, and 296. For six isotopes no events were observed, setting limits also in the 10-16 abundance range. For Rg291 and Rg294 we observed two and nine events, respectively, which results in an abundance in the 10-15 range. However, pileup of a particularly strong background in these cases makes a positive identification as Rg isotopeseven after pileup correctionunlikely.

  10. Natural variation of magnesium isotopes in mammal bones and teeth from two South African trophic chains

    NASA Astrophysics Data System (ADS)

    Martin, Jeremy E.; Vance, Derek; Balter, Vincent

    2014-04-01

    Isotopic fractionations accompanying element transfer through terrestrial ecosystems have the potential to shed light on ecological interactions between primary producers and consumers, but with the exception of carbon and nitrogen this potential has barely been exploited. Here, the magnesium stable isotope composition of bones and teeth of extant mammals from Kruger National Park (KNP) and Western Cape (WC), South Africa was measured for the first time. The nature of the geological substrate proves to be a major determinant of the ecosystem isotope baseline, as indicated by the lighter magnesium isotope ratios measured in WC mammals (ranging from -1.58‰ to -0.79‰) compared to those from KNP mammals (ranging from -1.01‰ to -0.04‰). Therefore, comparisons between the isotope signatures of taxa must be restricted to a pre-defined geographic area with a homogeneous substrate. In both parks, Mg shows slight enrichment in heavier isotopes from herbivores to carnivores. Plant remains trapped in the dentition of herbivores provide direct evidence of dietary source and, when available, were measured. In KNP only, δ26Mg of plant remains is systematically lighter than the values for herbivore teeth. These results invite further exploration of the variability of Mg isotopes in vertebrate ecosystems in order to test whether magnesium, a bio-essential element present in relatively large proportions in bone and teeth apatite, may serve as an additional trophic tracer to nitrogen, which is a constituent of collagen that rapidly degrades after burial.

  11. Upper limits for the existence of long-lived isotopes of roentgenium in natural gold

    SciTech Connect

    Dellinger, F.; Kutschera, W.; Forstner, O.; Golser, R.; Priller, A.; Steier, P.; Wallner, A.; Winkler, G.

    2011-01-15

    A sensitive search for isotopes of a superheavy element (SHE) in natural gold materials has been performed with accelerator mass spectrometry at the Vienna Environmental Research Accelerator, which is based on a 3-MV tandem accelerator. Because the most likely SHE in gold is roentgenium (Rg, Z = 111), the search concentrated on Rg isotopes. Two different mass regions were explored: (i) For the neutron-deficient isotopes {sup 261}Rg and {sup 265}Rg, abundance limits in gold of 3x10{sup -16} were reached (no events observed). This is in stark contrast to the findings of Marinov et al.[Int. J. Mod. Phys. E 18, 621 (2009)], who reported positive identification of these isotopes with inductively coupled plasma sector field mass spectrometry in the (1-10)x10{sup -10} abundance range. (ii) Theoretical models of SHEs predict a region of increased stability around the proton and neutron shell closures of Z = 114 and N = 184. We therefore investigated eight heavy Rg isotopes, {sup A}Rg, A = 289, 290, 291, 292, 293, 294, 295, and 296. For six isotopes no events were observed, setting limits also in the 10{sup -16} abundance range. For {sup 291}Rg and {sup 294}Rg we observed two and nine events, respectively, which results in an abundance in the 10{sup -15} range. However, pileup of a particularly strong background in these cases makes a positive identification as Rg isotopes--even after pileup correction--unlikely.

  12. ISOTOPE HYDROLOGY LABORATORY (WATER QUALITY MANAGEMENT BRANCH, WATER SUPPLY AND WATER RESOURCES DIVISION, NRMRL)

    EPA Science Inventory

    The mission of NRMRL's Water Supply and Water Resources Division's Isotope Hydrology Laboratory (IHL) is to resolve environmental hydrology problems through research and application of naturally occurring isotopes.The emergent field of isotope hydrology follows advances in anal...

  13. ANALYTICAL CAPABILITY - ISOTOPE HYDROLOGY LABORATORY (WATER QUALITY MANAGEMENT BRANCH, WATER SUPPLY AND WATER RESOURCES DIVISION, NRMRL)

    EPA Science Inventory

    The mission of NRMRL's Water Supply and Water Resources Division's Isotope Hydrology Laboratory is to resolve environmental hydrology problems through research and application of naturally occurring isotopes.Analytical capabilities at IHL include light stable isotope radio mass...

  14. Accidental Predissociation: A Special Case of Photo-Induced Isotope Fractionation Effect and Possible Occurrence in Nature

    NASA Astrophysics Data System (ADS)

    Chakraborty, S.; Thiemens, M. H.

    2009-12-01

    Photo-Induced Isotope Fractionation Effects (PHIFE) are known to produce isotopic frac-tionation in some photo-dissociating molecules (1-2). The PHIFE formalism is based on the Born-Oppenheimer approximation and the Reflection Principle. The isotopic fractionation arises principally from the spectral shift induced by the small difference in zero point energy between isotopologues and the contraction of the wave function due to isotopic substitution, consequently, the associated isotopic fractionations depends on the reduced mass of the isotopically substi-tuted species. The PHIFE formalism is only applicable to the molecules which undergo direct photo-dissociation that possess continuous absorption spectra. Simple molecules (N2, O2, CO) however do not follow a direct dissociation pathway and dissociate through an indirect process termed predissociation, which occurs when the molecule is excited to a quasi-bound state energetically above the dissociation continuum. The PHIFE formalism is not applicable when the absorption spectra are discrete. The assumption that the lightest isotopologues are preferentially predissociated is only valid for restricted predissociation cases. There is a special case of predissociation known as accidental predissociation (3), which takes place through an intermediate bound state in two steps (i) leakage to an intermediate bound state (coupled through spin orbit interaction) and, (ii) predissociation to a third quasi-bound state from the intermediate state. Line broadening at an accidental predissociation is a function of the magnitude of coupling matrix elements and the linewidths are strongly influenced by isotopic substitution (4). An anomalous isotopic effect in accidental predissociation was spectroscopically observed in CO (5), N2 (4) and BeH (6). We measured the isotopic fractionation for the first time in two accidental predissociating states of CO through VUV photodissociation using the 9.0.2 beamline at ALS (7-8). In light of these data, anomalous isotopic fractionations associated with accidental predissociation will be discussed for the CO and N2. These fractionations are important as VUV-photodissociation of CO and N2 have been invoked in solar nebula (self-shielding, (9-10)) to explain the observed iso-topic signatures in different solar system objects neglecting these isotope effects during photo-dissociation. References: 1. Y. L. Yung, C. E. Miller, Science 278, 1778 (1997). 2. S. Chakraborty, S. K. Bhattacharya, J. Chem. Phys. 118, 2164 (2003). 3. H. Lefebvre-Brion, R. W. Field, The Spectra and Dynamics of Diatomic Molecules. (Elsevier Academic Press, 2004). 4. A. J. Lorquet, J. C. Lorquet, Chem. Phys. Lett. 26, 138 (1974). 5. W. Ubachs, I. Velchev, P. Cacciani, J. Chem. Phys. 113, 547 (2000). 6. H. Lefebvre-Brion, R. Colin, J. Mol. Spectrosc. 65, 33 (1977). 7. S. Chakraborty, M. Ahmed, T. L. Jackson, M. H. Thiemens, Science 321, 1328 (2008). 8. S. Chakraborty, M. Ahmed, T. L. Jackson, M. H. Thiemens, Science 324, 4 (2009). 9. R. N. Clayton, Nature 415, 860 (2002). 10. J. R. Lyons, E. D. Young, Nature 435, 317 (2005).

  15. A naturally-occurring histone acetyltransferase inhibitor derived from Garcinia indica impairs newly acquired and reactivated fear memories.

    PubMed

    Maddox, Stephanie A; Watts, Casey S; Doyère, Valérie; Schafe, Glenn E

    2013-01-01

    The study of the cellular and molecular mechanisms underlying the consolidation and reconsolidation of traumatic fear memories has progressed rapidly in recent years, yet few compounds have emerged that are readily useful in a clinical setting for the treatment of anxiety disorders such as post-traumatic stress disorder (PTSD). Here, we use a combination of biochemical, behavioral, and neurophysiological methods to systematically investigate the ability of garcinol, a naturally-occurring histone acetyltransferase (HAT) inhibitor derived from the rind of the fruit of the Kokum tree (Garcina indica), to disrupt the consolidation and reconsolidation of Pavlovian fear conditioning, a widely studied rodent model of PTSD. We show that local infusion of garcinol into the rat lateral amygdala (LA) impairs the training and retrieval-related acetylation of histone H3 in the LA. Further, we show that either intra-LA or systemic administration of garcinol within a narrow window after either fear conditioning or fear memory retrieval significantly impairs the consolidation and reconsolidation of a Pavlovian fear memory and associated neural plasticity in the LA. Our findings suggest that a naturally-occurring compound derived from the diet that regulates chromatin function may be useful in the treatment of newly acquired or recently reactivated traumatic memories. PMID:23349897

  16. Assessment of naturally occurring covalent and total dimer levels in human IgG1 and IgG2.

    PubMed

    Yang, Jane; Goetze, Andrew M; Flynn, Gregory C

    2014-03-01

    Antibody dimers, two self-associated monomers, have been detected on both recombinantly expressed and endogenous human IgG proteins. Nearly 10 years ago, Yoo et al. (2003) described low levels of IgG2 covalent dimer, in human serum, but did not quantify the levels. Here we quantify the total and covalent dimer levels of IgG2 and IgG1 in human blood, and study the origin of covalent dimer formation. Low levels (<1%) of total IgG1 and IgG2 dimers were measured in freshly prepared human plasma. Both IgG1 and IgG2 covalent dimers were also found in plasma. Whereas IgG1 covalent dimer levels were significantly reduced by steps intended to eliminate artifacts during sample preparation, IgG2 covalent dimer levels remain stable in such conditions. About 0.4% of IgG2 in plasma was in a covalent dimer form, yet very little (<0.03%) of IgG1 covalent dimer could be considered naturally occurring. IgG2 dimer also formed in vitro under conditions designed to mimic those in blood, suggesting that formation occurs in vivo during circulation. Thus, small amounts of covalent IgG2 dimer do appear to form naturally. PMID:24321397

  17. A Novel Naturally Occurring Class I 5-Enolpyruvylshikimate-3-Phosphate Synthase from Janibacter sp. Confers High Glyphosate Tolerance to Rice

    PubMed Central

    Yi, Shu-yuan; Cui, Ying; Zhao, Yan; Liu, Zi-duo; Lin, Yong-jun; Zhou, Fei

    2016-01-01

    As glyphosate is a broad spectrum herbicide extensively used in agriculture worldwide, identification of new aroA genes with high level of glyphosate tolerance is essential for the development and breeding of transgenic glyphosate-tolerant crops. In this study, an aroA gene was cloned from a Janibacter sp. strain isolated from marine sediment (designated as aroAJ. sp). The purified aroAJ. sp enzyme has a Km value of 30 μM for PEP and 83 μM for S3P, and a significantly higher Ki value for glyphosate (373 μM) than aroAE. coli. AroAJ. sp is characterized as a novel and naturally occurring class I aroA enzyme with glyphosate tolerance. Furthermore, we show that aroAJ. sp can be used as an effective selectable marker in both japonica and indica rice cultivar. Transgenic rice lines were tested by herbicide bioassay and it was confirmed that they could tolerate up to 3360 g/ha glyphosate, a dosage four-fold that of the recommended agricultural application level. To our knowledge, it is the first report of a naturally occurring novel class I aroA gene which can be efficiently utilized to study and develop transgenic glyphosate-tolerant crops, and can facilitate a more economical and simplified weed control system. PMID:26754957

  18. A Naturally-Occurring Histone Acetyltransferase Inhibitor Derived from Garcinia indica Impairs Newly Acquired and Reactivated Fear Memories

    PubMed Central

    Maddox, Stephanie A.; Watts, Casey S.; Doyre, Valrie; Schafe, Glenn E.

    2013-01-01

    The study of the cellular and molecular mechanisms underlying the consolidation and reconsolidation of traumatic fear memories has progressed rapidly in recent years, yet few compounds have emerged that are readily useful in a clinical setting for the treatment of anxiety disorders such as post-traumatic stress disorder (PTSD). Here, we use a combination of biochemical, behavioral, and neurophysiological methods to systematically investigate the ability of garcinol, a naturally-occurring histone acetyltransferase (HAT) inhibitor derived from the rind of the fruit of the Kokum tree (Garcina indica), to disrupt the consolidation and reconsolidation of Pavlovian fear conditioning, a widely studied rodent model of PTSD. We show that local infusion of garcinol into the rat lateral amygdala (LA) impairs the training and retrieval-related acetylation of histone H3 in the LA. Further, we show that either intra-LA or systemic administration of garcinol within a narrow window after either fear conditioning or fear memory retrieval significantly impairs the consolidation and reconsolidation of a Pavlovian fear memory and associated neural plasticity in the LA. Our findings suggest that a naturally-occurring compound derived from the diet that regulates chromatin function may be useful in the treatment of newly acquired or recently reactivated traumatic memories. PMID:23349897

  19. Prevention of naturally occurring infectious bovine keratoconjunctivitis with a recombinant Moraxella bovis cytotoxin-ISCOM matrix adjuvanted vaccine.

    PubMed

    Angelos, John A; Hess, John F; George, Lisle W

    2004-12-01

    The efficacy of a recombinant Moraxella bovis cytotoxin subunit vaccine to prevent naturally occurring infectious bovine keratoconjunctivitis (IBK) was evaluated in a randomized, blinded, controlled field trial. Ninety-three cross bred beef calves were vaccinated with either saline, ISCOM matrix (adjuvant control), or a recombinant M. bovis cytotoxin carboxy terminus peptide plus ISCOM matrix and boostered 21 days later. Ocular examinations were performed once weekly for 20 weeks. At week 12, the cumulative proportion of calves with ulcerated eyes in the recombinant vaccine group was significantly lower than in the saline control group. Throughout the 20 week trial, the cumulative proportion of ulcerated calves remained lowest in the recombinant vaccine group. By week 7, nonulcerated calves in the recombinant vaccine group had significantly higher changes in serum neutralizing titers and cytotoxin specific to total IgG ratios in serum and tears as compared to calves in the control groups. The trend for a reduced cumulative proportion of IBK in the vaccinated calves over the 20 week trial suggests that a recombinant M. bovis cytotoxin vaccine may be beneficial in helping to prevent naturally occurring IBK. PMID:15530703

  20. A Novel Naturally Occurring Class I 5-Enolpyruvylshikimate-3-Phosphate Synthase from Janibacter sp. Confers High Glyphosate Tolerance to Rice.

    PubMed

    Yi, Shu-Yuan; Cui, Ying; Zhao, Yan; Liu, Zi-Duo; Lin, Yong-Jun; Zhou, Fei

    2016-01-01

    As glyphosate is a broad spectrum herbicide extensively used in agriculture worldwide, identification of new aroA genes with high level of glyphosate tolerance is essential for the development and breeding of transgenic glyphosate-tolerant crops. In this study, an aroA gene was cloned from a Janibacter sp. strain isolated from marine sediment (designated as aroAJ. sp). The purified aroAJ. sp enzyme has a Km value of 30 μM for PEP and 83 μM for S3P, and a significantly higher Ki value for glyphosate (373 μM) than aroAE. coli. AroAJ. sp is characterized as a novel and naturally occurring class I aroA enzyme with glyphosate tolerance. Furthermore, we show that aroAJ. sp can be used as an effective selectable marker in both japonica and indica rice cultivar. Transgenic rice lines were tested by herbicide bioassay and it was confirmed that they could tolerate up to 3360 g/ha glyphosate, a dosage four-fold that of the recommended agricultural application level. To our knowledge, it is the first report of a naturally occurring novel class I aroA gene which can be efficiently utilized to study and develop transgenic glyphosate-tolerant crops, and can facilitate a more economical and simplified weed control system. PMID:26754957

  1. Molecular Imprint of Exposure to Naturally Occurring Genetic Variants of Human Cytomegalovirus on the T cell Repertoire

    NASA Astrophysics Data System (ADS)

    Smith, Corey; Gras, Stephanie; Brennan, Rebekah M.; Bird, Nicola L.; Valkenburg, Sophie A.; Twist, Kelly-Anne; Burrows, Jacqueline M.; Miles, John J.; Chambers, Daniel; Bell, Scott; Campbell, Scott; Kedzierska, Katherine; Burrows, Scott R.; Rossjohn, Jamie; Khanna, Rajiv

    2014-02-01

    Exposure to naturally occurring variants of herpesviruses in clinical settings can have a dramatic impact on anti-viral immunity. Here we have evaluated the molecular imprint of variant peptide-MHC complexes on the T-cell repertoire during human cytomegalovirus (CMV) infection and demonstrate that primary co-infection with genetic variants of CMV was coincident with development of strain-specific T-cell immunity followed by emergence of cross-reactive virus-specific T-cells. Cross-reactive CMV-specific T cells exhibited a highly conserved public T cell repertoire, while T cells directed towards specific genetic variants displayed oligoclonal repertoires, unique to each individual. T cell recognition foot-print and pMHC-I structural analyses revealed that the cross-reactive T cells accommodate alterations in the pMHC complex with a broader foot-print focussing on the core of the peptide epitope. These findings provide novel molecular insight into how infection with naturally occurring genetic variants of persistent human herpesviruses imprints on the evolution of the anti-viral T-cell repertoire.

  2. Total synthesis of isotopically enriched Si-29 silica NPs as potential spikes for isotope dilution quantification of natural silica NPs.

    PubMed

    Plmai, Marcell; Szalay, Roland; Bartczak, Dorota; Varga, Zoltn; Nagy, Lvia Naszlyi; Gollwitzer, Christian; Krumrey, Michael; Goenaga-Infante, Heidi

    2015-05-01

    A new method was developed for the preparation of highly monodisperse isotopically enriched Si-29 silica nanoparticles ((29)Si-silica NPs) with the purpose of using them as spikes for isotope dilution mass spectrometry (IDMS) quantification of silica NPs with natural isotopic distribution. Si-29 tetraethyl orthosilicate ((29)Si-TEOS), the silica precursor was prepared in two steps starting from elementary silicon-29 pellets. In the first step Si-29 silicon tetrachloride ((29)SiCl4) was prepared by heating elementary silicon-29 in chlorine gas stream. By using a multistep cooling system and the dilution of the volatile and moisture-sensitive (29)SiCl4 in carbon tetrachloride as inert medium we managed to reduce product loss caused by evaporation. (29)Si-TEOS was obtained by treating (29)SiCl4 with absolute ethanol. Structural characterisation of (29)Si-TEOS was performed by using (1)H and (13)C nuclear magnetic resonance (NMR) spectroscopy and Fourier-transform infrared (FTIR) spectroscopy. For the NP preparation, a basic amino acid catalysis route was used and the resulting NPs were analysed using transmission electron microscopy (TEM), small angle X-ray scattering (SAXS), dynamic light scattering (DLS) and zeta potential measurements. Finally, the feasibility of using enriched NPs for on-line field-flow fractionation coupled with multi-angle light scattering and inductively coupled plasma mass spectrometry (FFF/MALS/ICP-MS) has been demonstrated. PMID:25617615

  3. Mechanistic insights into the formation of chloroform from natural organic matter using stable carbon isotope analysis

    NASA Astrophysics Data System (ADS)

    Breider, Florian; Hunkeler, Daniel

    2014-01-01

    Chloroform can be naturally formed in terrestrial environments (e.g. forest soils, peatland) by chlorination of natural organic matter (NOM). Recently, it was demonstrated that natural and anthropogenic chloroform have a distinctly different carbon isotope signature that makes it possible to identify its origin in soil and groundwater. In order to evaluate the contribution of different functional groups to chloroform production and factors controlling the isotopic composition of chloroform, carbon isotope trends during chlorination of model compounds, soil organic matter (SOM) and humic acids were evaluated, and apparent kinetic isotope effects (AKIEs) quantified. Phenol and propanone were selected as model compounds representing common functional groups in NOM. Chlorination was induced by hypochlorous acid to mimic natural chlorination. The pH ranged between 4 and 8 to cover typical soil conditions. For each model compound and pH, different AKIEs were observed. For phenol, the AKIE was normal at pH 4 (1.0156 0.0012) and inverse at pH 8 (0.9900 0.0007). For 2-propoanol, an opposite pH dependence was observed with an inverse AKIE at pH 4 (0.9935 0.0007) and a normal AKIE at pH 8 (1.0189 0.0016). The variations of the AKIE values suggest that the rate-limiting step of the reaction is either the re-hybridization of the carbon atom involved in chloroform formation or the hydrolysis of trichloroacetyl intermediates depending on the nature of functional group and pH. The chloroform formation from humic acid and SOM gives rise to small isotope variations. A comparison of the isotopic trends of chloroform formed from humic acid and SOM with those found for the model compounds suggest that opposed AKIE associated with the chlorination of phenolic and ketone moieties of NOM partly compensate each other during chlorination of NOM indicating that different types of functional groups contribute to chloroform formation.

  4. A Polymorphism in the Processing Body Component Ge-1 Controls Resistance to a Naturally Occurring Rhabdovirus in Drosophila

    PubMed Central

    Bayer, Florian; Jiggins, Francis M.

    2016-01-01

    Hosts encounter an ever-changing array of pathogens, so there is continual selection for novel ways to resist infection. A powerful way to understand how hosts evolve resistance is to identify the genes that cause variation in susceptibility to infection. Using high-resolution genetic mapping we have identified a naturally occurring polymorphism in a gene called Ge-1 that makes Drosophila melanogaster highly resistant to its natural pathogen Drosophila melanogaster sigma virus (DMelSV). By modifying the sequence of the gene in transgenic flies, we identified a 26 amino acid deletion in the serine-rich linker region of Ge-1 that is causing the resistance. Knocking down the expression of the susceptible allele leads to a decrease in viral titre in infected flies, indicating that Ge-1 is an existing restriction factor whose antiviral effects have been increased by the deletion. Ge-1 plays a central role in RNA degradation and the formation of processing bodies (P bodies). A key effector in antiviral immunity, the RNAi induced silencing complex (RISC), localises to P bodies, but we found that Ge-1-based resistance is not dependent on the small interfering RNA (siRNA) pathway. However, we found that Decapping protein 1 (DCP1) protects flies against sigma virus. This protein interacts with Ge-1 and commits mRNA for degradation by removing the 5’ cap, suggesting that resistance may rely on this RNA degradation pathway. The serine-rich linker domain of Ge-1 has experienced strong selection during the evolution of Drosophila, suggesting that this gene may be under long-term selection by viruses. These findings demonstrate that studying naturally occurring polymorphisms that increase resistance to infections enables us to identify novel forms of antiviral defence, and support a pattern of major effect polymorphisms controlling resistance to viruses in Drosophila. PMID:26799957

  5. Iron isotopes in the Seine River (France): Natural versus anthropogenic sources

    NASA Astrophysics Data System (ADS)

    Chen, Jiu-Bin; Busigny, Vincent; Gaillardet, Jrme; Louvat, Pascale; Wang, Yi-Na

    2014-03-01

    The determination of fluxes and isotope compositions of Fe transported from continents to the ocean is essential for understanding global surface Fe cycle and its effect on oceanic biological productivity. Contrasting to non-polluted rivers, Fe isotope composition in rivers strongly affected by human activities is poorly constrained. In this contribution, we present the first Fe isotope data in suspended particulate matter (SPM) and dissolved load of the human-impacted Seine River (France). Iron concentrations and isotope compositions, together with major and trace element concentrations, were measured for two sample sets: (1) a geographic transect along the river from headwater to estuary, and (2) a temporal series of samples collected in Paris from 2004 to 2007. In the Seine River, Fe is mostly carried by SPM (average 99% of the total Fe) rather than dissolved load. The high Fe enrichment factor (1.40, relative to natural fluvial pre-historical and headwater sediments) and strong correlation between SPM Fe and Zn concentrations (r2 = 0.70, n = 30) demonstrate a strong anthropogenic Fe input. The Fe isotope compositions in SPM show a very small range (?56Fe from -0.05 to 0.09) in spite of the large variations of Fe concentrations (from 1.78 to 4.17 wt.%) and are comparable to anthropogenic samples, suggesting that anthropogenic sources have similar Fe isotope composition to that of the natural background. In contrast, larger variations of Fe isotope compositions observed in the dissolved load (from -0.60 to 0.06) than that of SPM may provide a more promising means for tracing anthropogenic contributions to natural river systems. The ?56Fe and ?66Zn values of the dissolved loads are positively correlated (r2 = 0.62, n = 8), indicating a mixing between anthropogenic and natural end-members, enriched in light and heavy Fe isotopes respectively. Correlation between dissolved ?56Fe and DOC/Fe ratio (i.e. dissolved organic carbon/dissolved Fe concentrations) suggests that dissolved Fe of natural origin is mainly associated with organic colloids. The Fe compounds with low DOC/Fe ratio and ?56Fe values may correspond to anthropogenically-derived Fe-oxyhydroxide or sulfide colloids. Our study clearly demonstrates that polluted rivers transport an anthropogenic surplus flux of Fe that can be traced by coupling Fe and Zn isotopes. This surplus flux will fertilize the ocean and increase the primary productivity of phytoplankton, and thus may ultimately impact the global carbon cycle.

  6. Dual Infection and Superinfection Inhibition of Epithelial Skin Cells by Two Alphaherpesviruses Co-Occur in the Natural Host

    PubMed Central

    Jarosinski, Keith W.

    2012-01-01

    Hosts can be infected with multiple herpesviruses, known as superinfection; however, superinfection of cells is rare due to the phenomenon known as superinfection inhibition. It is believed that dual infection of cells occurs in nature, based on studies examining genetic exchange between homologous alphaherpesviruses in the host, but to date, this has not been directly shown in a natural model. In this report, gallid herpesvirus 2 (GaHV-2), better known as Mareks disease virus (MDV), was used in its natural host, the chicken, to determine whether two homologous alphaherpesviruses can infect the same cells in vivo. MDV shares close similarities with the human alphaherpesvirus, varicella zoster virus (VZV), with respect to replication in the skin and exit from the host. Recombinant MDVs were generated that express either the enhanced GFP (eGFP) or monomeric RFP (mRFP) fused to the UL47 (VP13/14) herpesvirus tegument protein. These viruses exhibited no alteration in pathogenic potential and expressed abundant UL47-eGFP or -mRFP in feather follicle epithelial cells in vivo. Using laser scanning confocal microscopy, it was evident that these two similar, but distinguishable, viruses were able to replicate within the same cells of their natural host. Evidence of superinfection inhibition was also observed. These results have important implications for two reasons. First, these results show that during natural infection, both dual infection of cells and superinfection inhibition can co-occur at the cellular level. Secondly, vaccination against MDV with homologous alphaherpesvirus like attenuated GaHV-2, or non-oncogenic GaHV-3 or meleagrid herpesvirus (MeHV-1) has driven the virus to greater virulence and these results implicate the potential for genetic exchange between homologous avian alphaherpesviruses that could drive increased virulence. Because the live attenuated varicella vaccine is currently being administered to children, who in turn could be superinfected by wild-type VZV, this could potentiate recombination events of VZV as well. PMID:22629393

  7. Naturally occurring proteinaceous nanoparticles in Coptidis Rhizoma extract act as concentration-dependent carriers that facilitate berberine absorption

    PubMed Central

    Ma, Bing-Liang; Yin, Chun; Zhang, Bo-Kai; Dai, Yan; Jia, Yi-Qun; Yang, Yan; Li, Qiao; Shi, Rong; Wang, Tian-Ming; Wu, Jia-Sheng; Li, Yuan-Yuan; Lin, Ge; Ma, Yue-Ming

    2016-01-01

    Pharmacological activities of some natural products diminish and even disappear after purification. In this study, we explored the mechanisms underlying the decrease of acute oral toxicity of Coptidis Rhizoma extract after purification. The water solubility, in vitro absorption, and plasma exposure of berberine (the major active compound) in the Coptidis Rhizoma extract were much better than those of pure berberine. Scanning electron microscopy, laser scanning confocal microscopy (LSCM), and dynamic light scattering experiments confirmed that nanoparticles attached to very fine precipitates existed in the aqueous extract solution. The LSCM experiment showed that the precipitates were absorbed with the particles by the mouse intestine. High-speed centrifugation of the extract could not remove the nanoparticles and did not influence plasma exposure or acute oral toxicity. However, after extract dilution, the attached precipitates vanished, although the nanoparticles were preserved, and there were no differences in the acute oral toxicity and plasma exposure between the extract and pure berberine. The nanoparticles were then purified and identified as proteinaceous. Furthermore, they could absorb co-dissolved berberine. Our results indicate that naturally occurring proteinaceous nanoparticles in Coptidis Rhizoma extract act as concentration-dependent carriers that facilitate berberine absorption. These findings should inspire related studies in other natural products. PMID:26822920

  8. Analysis in natural time domain of geoelectric time series monitored prior two strong earthquakes occurred in Mexico

    NASA Astrophysics Data System (ADS)

    Ramrez-Rojas, A.; Flores-Marquez, L. E.

    2009-12-01

    The short-time prediction of seismic phenomena is currently an important problem in the scientific community. In particular, the electromagnetic processes associated with seismic events take in great interest since the VAN method was implemented. The most important features of this methodology are the seismic electrical signals (SES) observed prior to strong earthquakes. SES has been observed in the electromagnetic series linked to EQs in Greece, Japan and Mexico. By mean of the so-called natural time domain, introduced by Varotsos et al. (2001), they could characterize signals of dichotomic nature observed in different systems, like SES and ionic current fluctuations in membrane channels. In this work we analyze SES observed in geoelectric time series monitored in Guerrero, Mxico. Our analysis concern with two strong earthquakes occurred, on October 24, 1993 (M=6.6) and September 14, 1995 (M=7.3). The time series of the first one displayed a seismic electric signal six days before the main shock and for the second case the time series displayed dichotomous-like fluctuations some months before the EQ. In this work we present the first results of the analysis in natural time domain for the two cases which seems to be agreeing with the results reported by Varotsos. P. Varotsos, N. Sarlis, and E. Skordas, Practica of the Athens Academy 76, 388 (2001).

  9. Naturally occurring proteinaceous nanoparticles in Coptidis Rhizoma extract act as concentration-dependent carriers that facilitate berberine absorption.

    PubMed

    Ma, Bing-Liang; Yin, Chun; Zhang, Bo-Kai; Dai, Yan; Jia, Yi-Qun; Yang, Yan; Li, Qiao; Shi, Rong; Wang, Tian-Ming; Wu, Jia-Sheng; Li, Yuan-Yuan; Lin, Ge; Ma, Yue-Ming

    2016-01-01

    Pharmacological activities of some natural products diminish and even disappear after purification. In this study, we explored the mechanisms underlying the decrease of acute oral toxicity of Coptidis Rhizoma extract after purification. The water solubility, in vitro absorption, and plasma exposure of berberine (the major active compound) in the Coptidis Rhizoma extract were much better than those of pure berberine. Scanning electron microscopy, laser scanning confocal microscopy (LSCM), and dynamic light scattering experiments confirmed that nanoparticles attached to very fine precipitates existed in the aqueous extract solution. The LSCM experiment showed that the precipitates were absorbed with the particles by the mouse intestine. High-speed centrifugation of the extract could not remove the nanoparticles and did not influence plasma exposure or acute oral toxicity. However, after extract dilution, the attached precipitates vanished, although the nanoparticles were preserved, and there were no differences in the acute oral toxicity and plasma exposure between the extract and pure berberine. The nanoparticles were then purified and identified as proteinaceous. Furthermore, they could absorb co-dissolved berberine. Our results indicate that naturally occurring proteinaceous nanoparticles in Coptidis Rhizoma extract act as concentration-dependent carriers that facilitate berberine absorption. These findings should inspire related studies in other natural products. PMID:26822920

  10. Evaluation of naturally occurring radioactive materials (NORMs) in inorganic and organic oilfield scales from the Middle East.

    PubMed

    Bassioni, Ghada; Abdulla, Fareed; Morsy, Zeinab; El-Faramawy, Nabil

    2012-04-01

    The distribution of natural nuclide gamma-ray activities and their respective annual effective dose rates, produced by potassium-40 (??K), uranium-238 (?U), thorium-232 (Th), and radium-226 (?Ra), were determined for 14 oilfield scale samples from the Middle East. Accumulated radioactive materials concentrate in tubing and surface equipment, and workers at equipment-cleaning facilities and naturally occurring radioactive materials (NORMs) disposal facilities are the population most at risk for exposure to NORM radiation. Gamma-spectra analysis indicated that photo-gamma lines represent the parents of 10 radioactive nuclides: ?Th, plutonium-239, actinium-228, ?Ra, lead-212 (Pb), ?Pb, thallium-238 (??Tl), bismuth-212 (Bi), ?Bi, and ??K. These nuclides represent the daughters of the natural radioactive series ?U and Th with ??K as well. The mean activity concentration of ?U, Th, and ??K were found to be 25.8 11.6, 18.3 8.1, and 4487.2 2.5% Bq kg? (average values for 14 samples), respectively. The annual effective dose rates and the absorbed doses in air, both indoor and outdoor, for the samples were obtained as well. The results can be used to assess the respective hazard on workers in the field and represent a basis for revisiting current engineering practices. PMID:21892762

  11. Molecular identification of naturally occurring bacteriocinogenic and bacteriocinogenic-like lactic acid bacteria in raw milk and soft cheese.

    PubMed

    Ortolani, M B T; Moraes, P M; Perin, L M; Viosa, G N; Carvalho, K G; Silva Jnior, A; Nero, L A

    2010-07-01

    Lactic acid bacteria (LAB) are currently used by food industries because of their ability to produce metabolites with antimicrobial activity against gram-positive pathogens and spoilage microorganisms. The objectives of this study were to identify naturally occurring bacteriocinogenic or bacteriocinogenic-like LAB in raw milk and soft cheese and to detect the presence of nisin-coding genes in cultures identified as Lactococcus lactis. Lactic acid bacteria cultures were isolated from 389 raw milk and soft cheese samples and were later characterized for the production of antimicrobial substances against Listeria monocytogenes. Of these, 58 (14.9%) LAB cultures were identified as antagonistic; the nature of this antagonistic activity was then characterized via enzymatic tests to confirm the proteinaceous nature of the antimicrobial substances. In addition, 20 of these antagonistic cultures were selected and submitted to genetic sequencing; they were identified as Lactobacillus plantarum (