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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. 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.

  3. 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...

  4. 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...

  5. 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 ...

  6. 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.; Böhlke, 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.

  7. 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

  8. Analysis of Long-Term Diet Changes in Tropical Seabirds Using Naturally Occurring Stable Isotopes

    NASA Astrophysics Data System (ADS)

    Vilchis, I.; Ballance, L.

    2010-12-01

    A clear understanding of ecosystem response to past environmental changes will provide more accurate interpretations of current ecosystem trends. With this mindset, we investigated the effects of the 1976/77 regime shift in the Pacific Ocean on a tropical pelagic community of apex predators. Using study skins from museum collections from 1960 to 2006, we measured stable carbon (δ13C) and nitrogen (δ15N) isotopes for a suite of ecologically and phylogenetically diverse seabirds from the eastern Pacific warm pool. In this region, seabirds generally forage by depending on subsurface predators to drive prey to the surface or by associating with oceanographic features that increase productivity or aggregate prey in space and time. We found that annual δ15N means from Sooty Terns’ (Onychoprion fuscatus) feathers decreased by 2.98‰, while all other species did not show any significant trends over the study period. Annual δ13C means from feathers of Sooty Terns, Wedge-tailed Shearwaters (Puffinus pacificus), Red-footed Boobies (Sula sula) and Juan Fernandez Petrels (Petrodroma externa) decreased by an average of 1.02‰, at rates between 0.01 and 0.02 δ13C‰ per year-1. Our results do not suggest a response of the seabird community to the 1976/77 regime shift. Instead, they are consistent with a trophic shift and/or change in foraging area for Sooty Terns and a long-term decrease in feather δ13C for the eastern Pacific warm pool seabird community. This long-term decrease in feather δ13C is most likely due to the Suess effect and less likely due to a decline in primary productivity of the system. We hypothesize that a deepening trend in thermocline depth in the eastern Pacific warm pool affected Sooty Terns more than other species in the subsurface predator-dependent guild that depend less on smaller subsurface predators like skipjack tuna.

  9. 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

  10. "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.

  11. Naturally occuring mutagens.

    PubMed

    Clark, A M

    1976-01-01

    Naturally occurring mutagens have usually been discovered as a result of outbreaks of disease in agricultural livestock, or as a result of epidemiological studies of cancer of the liver in man. Subsequent work has then shown that the toxic agents responsible often have mutagenic properties. Examples are the pyrrolizidine alkaloids, cyasin, a range of mycotoxins produced by various fungi, and at least two unidentified toxic agents in bracken. Commonly the toxic agent itself does not show high biological activity, but after ingestion it is converted by metabolic processes into the active mutagen or carcinogen. Some of these toxic substances have been responsible for considerable losses of agricultural livestock and therefore are of economic significance. From the view-point of genetic hazards to man, the most significant compounds are probably the mycotoxins, e.g. aflatoxin, because of the common risk of fungal contamination of food, especially in tropical regions. No information is yet available on the effects of these mutagens on natural populations of animals. Plants containing the pyrrolizidine alkaloids are found in areas of Africa and the Middle East where plagues of the migratory locust occur. Although it is known that some of the alkaloids can induce chromosomal damage in grasshoppers, whether such damage ever becomes a significant factor under ecological conditions is not known. In some cases, insects have not only evolved resistance towards mutagenic alkaloids but have become dependent on them for certain purposes. The males of certain Danaid butterflies feed on plants containing pyrrolizidine alkaloids. After ingestion, the alkaloids are metabolised to dihydropyrrolizine derivatives, which are then secreted on special organs (hair pencils) and, following dissemination into the atmosphere, act as pheromones for the stimulation of mating behaviour. PMID:958226

  12. 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

  13. Naturally occurring cardiac glycosides.

    PubMed

    Radford, D J; Gillies, A D; Hinds, J A; Duffy, P

    1986-05-12

    Cardiac glycoside poisoning from the ingestion of plants, particularly of oleanders, occurs with reasonable frequency in tropical and subtropical areas. We have assessed a variety of plant specimens for their cardiac glycoside content by means of radioimmunoassays with antibodies that differ in their specificity for cardiac glycosides. Significant amounts of immunoreactive cardiac glycoside were found to be present in the ornamental shrubs: yellow oleander (Thevetia peruviana); oleander (Nerium oleander); wintersweet (Carissa spectabilis); bushman's poison (Carissa acokanthera); sea-mango (Cerbera manghas); and frangipani (Plumeria rubra); and in the milkweeds: redheaded cotton-bush (Asclepias curassavica); balloon cotton (Asclepias fruiticosa); king's crown (Calotropis procera); and rubber vine (Cryptostegia grandifolia). The venom gland of the cane toad (Bufo marinus) also contained large quantities of cardiac glycosides. The competitive immunoassay method permits the rapid screening of specimens that are suspected to contain cardiac glycosides. Awareness of the existence of these plant and animal toxins and their dangers allows them to be avoided and poisoning prevented. The method is also useful for the confirmation of the presence of cardiac glycosides in serum in cases of poisoning. PMID:3086679

  14. 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

  15. 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

  16. Naturally occurring methyl salicylate glycosides.

    PubMed

    Mao, Ping; Liu, Zizhen; Xie, Meng; Jiang, Rui; Liu, Weirui; Wang, Xiaohong; Meng, Shen; She, Gaimei

    2014-01-01

    As an important part of non steroids anti-inflammation drug (NSAIDs), salicylate has developed from natural substance salicylic acid to natrium salicylicum, to aspirin. Now, methyl salicylate glycoside, a new derivative of salicylic acid, is modified with a -COOH group integrated one methyl radical into formic ether, and a -OH linked with a monosaccharide, a disaccharide or a trisaccharide unit by glycosidic linkage. It has the similar pharmacological activities, anti-inflammatory, analgesic, antipyretic and antithrombotic as the previous salicylates' without resulting in serious side effects, particularly the gastrointestinal toxicity. Owing to the superiority of those significant bioactivities, methyl salicylate glycosides have became a hot research area in NSAIDs for several years. This paper compiles all 9 naturally occurring methyl salicylate glycosides, their distribution of the resource and pharmacological mechanism, which could contribute to the new drug discovery. PMID:24329991

  17. 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...

  18. 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.

  19. Trypanosomiasis in mice with naturally occurring immunodeficiencies.

    PubMed Central

    Jones, J F; Hancock, G E

    1983-01-01

    By using mice with naturally occurring defects, we have shown that an intact macrophage system is crucial to survival with the pathogenic protozoan Trypanosoma rhodesiense, since a defect in these cells decreased survival by half. Deficiencies in natural killer cell function or complement levels had no effect on survival. However, the capacity to survive trypanosomiasis was not related to the levels of parasitemia achieved during infection. PMID:6605927

  20. 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

  1. 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

  2. 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

  3. 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.

  4. Cocaine as a naturally occurring insecticide.

    PubMed Central

    Nathanson, J A; Hunnicutt, E J; Kantham, L; Scavone, C

    1993-01-01

    Although cocaine has a fascinating and complex medicinal history in man, its natural function in plants is unknown. The present studies demonstrate that cocaine exerts insecticidal effects at concentrations which occur naturally in coca leaves. Unlike its known action on dopamine reuptake in mammals, cocaine's pesticidal effects are shown to result from a potentiation of insect octopaminergic neurotransmission. Amine-reuptake blockers of other structural classes also exert pesticidal activity with a rank order of potency distinct from that known to affect vertebrate amine transporters. These findings suggest that cocaine functions in plants as a natural insecticide and that octopamine transporters may be useful sites for targeting pesticides with selectivity toward invertebrates. Images Fig. 3 PMID:8415755

  5. Leaching of technologically enhanced naturally occurring radioactive materials.

    PubMed

    Chau, Nguyen Dinh; Chruściel, Edward

    2007-08-01

    A form of waste associated with mining activities is related to the type of deposit being mined and to the procedure of exploitation and enrichment adopted. The wastes usually contain relatively large amounts of technologically enhanced naturally occurring radioactive materials (TENORM). The TENORM are often stored on the surface. Consequently, they can be leached as a result of interaction with aqueous solutions of different chemical composition. This further leads to pollution of water and soil in the vicinity of the stored wastes. The paper presents the results of laboratory investigation aimed at quantifying the leaching process of samples originating from uranium dumps and storage reservoirs associated with brine pumped from coal mines. The leaching process was investigated with respect to selected elements: uranium isotopes, radium isotopes, iron, barium and sodium. The samples were exposed to aqueous solutions of different chemical composition. The experiments revealed that TENORM in form of sulphate compounds are the most resistant against leaching. The leaching coefficient for radium isotopes varies from a few thousandth percent to a few hundredth percent. On the other hand, for TENORM occurring in sand or sludge, the leaching coefficient for uranium and radium isotopes ranged from a few hundredth percent to a few percent. PMID:17482828

  6. Gold: compositional variations of naturally occurring alloys

    SciTech Connect

    Craig, J.R.; Rimstidt, J.D.

    1985-01-01

    Naturally occurring gold is nearly always alloyed with silver, quantities of which may reach 40 or more percent, and frequently contains minor amounts of copper and mercury and traces of other metals. An extensive literatures search of analyses of gold alloys from world-wide localities, supplemented by several hundred additional electron microprobe analyses, yields the distribution pattern in terms of fineness (((Au)/(Au+Ag) wt %) x 1000). These data reveal few compositions in the range 0-500 fine and a maximum at approximately 920 fine. The near absence of compositions in the 0-500 fineness range and a few examples of coexisting silver and electrum (540 fine) suggest the existence of a miscibility gap at low temperatures. Copper contents generally increase with higher fineness; several natural examples reveal exsolution of cuprian gold and thus indicate another miscibility gap. Natural mercury contents are generally below 0.5 wt %, but placer gold grains commonly reveal surface contamination of mercury lost in streams by former recovery operations. Thin, sharply defined rims of very high fineness gold commonly have developed on placer gains in streams and soil zones.

  7. Naturally occurring secoiridoids and bioactivity of naturally occurring iridoids and secoiridoids. A review, part 2.

    PubMed

    Dinda, Biswanath; Debnath, Sudhan; Harigaya, Yoshihiro

    2007-05-01

    Naturally occurring new secoiridoids published during 1994-2005 are reviewed with available physical and spectral data: mp, [alpha](D), UV, IR, (1)H- and (13)C-NMR and plant source. The works on biological and pharmacological activity of naturally occurring iridoids and secoiridoids reported during 1998-2005 are also reviewed. Bioactivities like antiallergic, antiarthritis, antibacterial, anticancer, anticoagulant, anticomplement, antifungal, antiinflammatory, antioxidative, antiprotozoal, antispasmodic, antiviral, immunomodulatory, neuroprotective, nerve growth factor potentiating and wound healing activities are highlighted. PMID:17473457

  8. 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.

  9. 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

  10. 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

  11. Human exposure to naturally occurring hydroquinone.

    PubMed

    Deisinger, P J; Hill, T S; English, J C

    1996-01-01

    Hydroquinone (HQ) is a nonvolatile chemical used in the photographic, rubber, chemical, and cosmetic industries. HQ is also known to occur in nature as the beta-D-glucopyranoside conjugate (arbutin), and free HQ is a known component of cigarette smoke. Low concentrations of HQ have been detected in the urine and plasma of humans with no occupational or other known exposure to HQ. The studies reported here investigate dietary and other potential sources of HQ and their contribution to HQ concentrations in the plasma and urine of human volunteers. Analysis of possible food sources of HQ by GC indicated significant amounts of arbutin in wheat products (1-10 ppm), pears (4-15 ppm), and coffee and tea (0.1 ppm). Free HQ was found in coffee (0.2 ppm), red wine (0.5 ppm), wheat cereals (0.2-0.4 ppm), and broccoli (0.1 ppm). After consuming a meal including arbutin- and HQ-containing foods, volunteers showed significant increases in plasma and urinary levels of HQ and its conjugated metabolites (total HQ). Mean plasma concentrations of total HQ peaked at 5 times background levels at 2 h after the completion of the meal, and mean urinary excretion rates of total HQ peaked at 12 times background at 2-3 h after the meal. Immediately after smoking four cigarettes in approximately 30 min, mean plasma concentrations of total HQ were maximally 1.5 times background levels; mean urinary excretion rates of total HQ peaked at 2.5 times background at 1-3 h after smoking. These data indicate that considerable human exposure to HQ can result from plant-derived dietary sources and, to a lesser extent, from cigarette smoke. PMID:8568910

  12. 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

  13. Naturally occurring antibodies against Mycobacterium avium complex.

    PubMed

    Bermudez, L E; Wu, M; Enkel, H; Young, L S

    1989-01-01

    Serum obtained from 57 healthy individuals and patients admitted to the hospital owing to diverse pathological causes, as well as serum from seven patients with AIDS and disseminated Mycobacterium avium complex (MAC) infection, were studied to determine the prevalence of IgG and IgM antibodies against surface proteins of M. avium complex. Immunodot assay to detect serum positivity against MAC and Western Blot technique in order to determine the MAC antigens eliciting antibody production were performed. Sera from 89 percent and 81 percent of the non-AIDS population had IgG and IgM antibodies against MAC antigens, respectively. In contrast, 43 percent and 71 percent of the AIDS population had IgG and IgM antibodies against MAC antigens, respectively, in the serum. To define further the antigens recognized by these naturally occurring antibodies, the serum of 14 non-AIDS and four acquired immunodeficiency syndrome (AIDS) patients were studied. Multiple antigens of MAC, with molecular weight ranging from 10 to 95 kilodaltons were recognized by IgG and IgM antibodies present in the sera. The IgM type antibodies were shown to react mainly against 10 kilodalton and 31 kilodalton antigenic protein, while the IgG type antibodies were produced mainly against the 10, 31, and 65 kilodalton proteins. Although the pattern of reaction was consistent between non-AIDS and AIDS populations, IgM antibodies were not detected against the 10 kilodalton protein nor were IgG antibodies detected against the 31 kilodalton protein in the AIDS population. PMID:2690731

  14. 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.

  15. 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.

  16. 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

  17. 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

  18. 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

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

    PubMed

    da Silva, Márcio 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, 0.01-1.4µgL(-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→Tefé; Manacapuru→Manaus; Presidente Figueiredo→São Sebastião do Uatumã; 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

  2. 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/...

  3. 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.

  4. 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.

  5. 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

  6. 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

  7. 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…

  8. 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

  9. 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)

  10. 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.

  11. 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

  12. 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.;

  13. 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.

  14. 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.

  15. 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

  16. 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.

  17. Syntheses of naturally occurring terphenyls and related compounds.

    PubMed

    Sawayama, Yusuke; Tsujimoto, Takashi; Sugino, Kumi; Nishikawa, Toshio; Isobe, Minoru; Kawagishi, Hirokazu

    2006-12-01

    Naturally occurring terphenyls and related compounds such as terferol and its corresponding quinone and phlebiarubrone were synthesized from 2,5-diphenyl-1,4-benzoquinone. According to the proposed biosynthetic pathway, chemical conversion of phlebiarubrone to ustalic acid, a toxic compound isolated from the poisonous mushroom, Tricholoma ustale, was examined to find a low-yield conversion to the ustalic acid dimethyl ester. PMID:17151478

  18. 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

  19. Biological and pharmacological activity of naturally occurring iridoids and secoiridoids.

    PubMed

    Ghisalberti, E L

    1998-04-01

    The biological and pharmacological activities reported for naturally occurring iridoids and secoiridoids are reviewed. The hypothesis that iridoid glycoside and acetal esters can best be considered as pro-drugs and that corresponding hemiacetals and compounds derived from them carry the pharmacophores is discussed. The possibility that the activity of some iridoids is determined by their conversion to pyridine monoterpene alkaloids (PMTA) is also considered. The evidence available suggests that iridoids show activities consistent with those presented by immunomodulators and adaptogens. PMID:23195768

  20. 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.

  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. Issues related to regulatory control of naturally occurring radioactive materials

    SciTech Connect

    Chen, S.Y.

    1997-04-01

    Nearly 80% of human radiation exposure is from naturally occurring radioactive materials (NORM). While exposure from man-made sources of radiation has been well regulated, no consistent regulatory controls exist for NORM. Because elevated radiation levels have resulted from NORM enhancement activities such as occur in the petroleum, fertilizer, mining, and processing industries, some form of regulatory control is in order. In the US, regulation of NORM by federal agencies such as the Nuclear Regulatory Commission or the Environmental Protection Agency is not anticipated in the near future because there are no authorizing federal statutes. Important issues for addressing the control of NORM include source characterization and generation, radiation protection concerns, waste management and disposition, and the regulatory framework.

  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

    NASA Astrophysics Data System (ADS)

    Hunt, Ronald D.; Blake, Beverly J.; Chalifoux, Laura V.; Sehgal, Prabhat K.; King, Norval W.; Letvin, Norman L.

    1983-08-01

    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.

  7. 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

  8. 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

  9. 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

  10. 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

  11. Using Administrative Data to Identify Naturally Occurring Networks of Physicians

    PubMed Central

    Landon, Bruce E.; Onnela, Jukka-Pekka; Keating, Nancy L.; Barnett, Michael L.; Paul, Sudeshna; O’Malley, A. James; Keegan, Thomas; Christakis, Nicholas A.

    2013-01-01

    Background Physicians naturally form networks. Networks could form a rational basis for Accountable Care Organizations (ACOs) for defined populations of Medicare beneficiaries. Objectives To use methods from network science to identify naturally occurring networks of physicians that might be best suited to becoming ACOs. Research Design, Subjects, and Measures Using nationally representative claims data from the Medicare program for CY 2006 on 51 hospital referral regions (HRRs), we used a network-science based community-detection algorithm to identify groups of physicians likely to have pre-established relationships. We examined the proportion of care delivered within communities and compared our results to potential ACOs organized around single hospitals. Results We studied 4,586,044 Medicare beneficiaries from 51 HRRs who were seen by 68,288 active physicians practicing in those HRRs. The median community-based network ACO had 150 physicians with 5,928 ties whereas the median hospital-based network ACO had 96 physicians with 3,276 ties. Seventy-seven percent of physician visits occurred with physicians in the community-based networks as compared with 56% with physicians in the hospital-based networks; however, just 8% of specialist visits were to specialists within the hospital-based networks as compared with 60% of specialist visits within the community-based networks. Some markets seemed better suited to developing ACOs based on network communities than others. Conclusions We present a novel approach to identifying groups of physicians that might readily function as ACOs. Organic networks identified and defined in this natural and systematic manner already have physicians who exhibit close working relationships, and who, importantly, keep the vast majority of care within the networks. PMID:23807593

  12. 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

  13. Additive CHARMM force field for naturally occurring modified ribonucleotides

    PubMed Central

    Xu, You; Vanommeslaeghe, Kenno; Aleksandrov, Alexey; MacKerell, Alexander D.

    2016-01-01

    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

  14. 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.

  15. Status of EPA program: Naturally occurring radioactive materials (NORM)

    SciTech Connect

    Boyd, M.

    1997-12-31

    This paper provides a status report on actions by the Environmental Protection Agency (EPA) to provide guidance regarding radiation protection from naturally occurring radioactive materials (NORM). The talk discusses three aspects of EPA`s work: contract studies; CRCPD draft NORM regulations; sewage NORM projects. Contract studies have concentrated on response to the Diffuse NORM report issued in May 1993. Work has been done on waste characterization, risk assessment, and radiation exposure pathways. New draft exposure regulations are being proposed which include flexibility for states regarding the fraction of the yearly exposure which could come from TENORM sources. Sewage work has included guidance on typical radioisotopes found, what different agencies can do, how to respond to radiation, who to contact, etc.

  16. 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

  17. 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

  18. 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

  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. 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

  1. 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

  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. 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.

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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.

  9. 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 5α-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

  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. 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.

  12. 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

  13. 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.

  14. Volatile analysis of ground almonds contaminated with naturally occurring fungi.

    PubMed

    Beck, John J; Mahoney, Noreen E; Cook, Daniel; Gee, Wai S

    2011-06-01

    Aflatoxigenic aspergilli inflict major economic damage to the tree nut industry of California, with the highest negative impact to almonds. Aspergilli and fungi in general are known to emit volatiles in varying quantity and composition dependent upon their growth media. The goal of the study was to determine the volatile emission of whole and blanched almonds that had been picked out and labeled as inedible by processors. The aflatoxin content and number of colony forming units of each sample were also determined. A total of 23 compounds were consistently detected and identified. Several volatiles from the blanched almonds demonstrated significant increases when compared to the emissions of whole almonds. Several of these volatiles are considered fatty acid decomposition products and included hexanal, heptanal, octanal, nonanal, 3-octen-2-one, tetramethylpyrazine, and decanal. The almond samples investigated were characteristic of a typical postharvest environment and illustrative of potential contamination within a stockpile or transport container. Volatiles indicative of fatty acid decomposition were predominant in the samples that underwent some form of blanching. The emission amounts of hexanal, heptanal, octanal, and hexanoic acid increased 3-fold in samples contaminated with aflatoxin; however, due to variability between samples they could not be considered as indicator volatiles for aflatoxin content. The emission profile of volatiles from almond kernels contaminated with naturally occurring aspergilli and associated fungi is heretofore unreported. PMID:21528918

  15. 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.

  16. Surveillance programmes for managing risks from naturally occurring toxicants.

    PubMed

    Park, D L

    1995-01-01

    Aflatoxins are potent carcinogenic, mutagenic and teratogenic metabolites produced by moulds that grow on food and feed. Their toxicity has caused severe health and economic problems worldwide. Other mycotoxins which have been associated with human health risks include ergot alkaloids, citreoviridin, trichothecenes, ochratoxins, citrinin, tremorgenic mycotoxins and the fumonisins. Many phycotoxins have also been associated with human illnesses; these phycotoxins include paralytic shellfish poisons, diarrhoeic shellfish poisons, ciguatera-related toxins, neurotoxic shellfish poisons, tetrodotoxin and, the more recently discovered, domoic acid which is associated with amnesic shellfish poisoning. Human exposure to these naturally occurring toxins can be from direct consumption of contaminated commodities or from foods derived from animals previously exposed to these toxins in their feed. Food safety monitoring programmes for selected toxins have been established for raw and finished products susceptible to contamination. Components of these control programme include the establishment of regulatory limits or guidelines, monitoring susceptible products for specific compounds, and the diversion of the contaminated products to lower-risk uses and/or decontamination procedures. PMID:7664929

  17. Nortestosterone is not a naturally occurring compound in male cattle.

    PubMed

    McEvoy, J D; McCaughey, W J; Cooper, J; Kennedy, D G; McCartan, B M

    1999-01-01

    Nortestosterone (beta-NT) is a hormonal growth promoter banned from livestock production in the EU. Following injection, the major metabolite in cattle is the 17 alpha-epimer (alpha-NT). However, this also occurs naturally in pregnant cattle. It is not known whether alpha-NT is also endogenous to intact or castrated male cattle. Three surveys were undertaken to assess whether alpha-NT is naturally produced in this subset of the population. Bile samples from a total of 1,281 cattle (73 bulls and 1,208 steers) from 366 herds were collected at slaughter and initially screened by using a semi-automated EIA with multi-analyte immunoaffinity chromatography (IAC) clean-up. Bile samples from a further 38 male cattle (10 bulls and 28 steers) were analysed by high-resolution gas chromatography-mass spectrometry (GC-MS) with IAC pretreatment. Only samples containing more than 2 ng/ml alpha-NT were subjected to GC-MS. With 2 ng/ml alpha-NT as a threshold for confirmatory testing, the false positive rate of the screening EIA was 1.8%. Bulls (n = 16) and steers (n = 179) from government farms (n = 2) and which were not treated with exogenous beta-NT, did not have measurable concentrations of alpha-NT in their bile. Bulls (n = 35) and steers (n = 606) taken from herds (n = 204) which had no previous history of illegal growth promoter abuse also did not have alpha-NT in their bile. Of 32 bulls and 451 steers of unknown treatment history sampled from herds (n = 160), 56 steers from 19 herds contained GC-MS confirmed concentrations of alpha-NT higher than the limit of quantification of the assay LOQ (0.7 ng/ml). Of these animals, two had beta-NT-containing injection sites and five had residues of the beta-agonists clenbuterol and mabuterol. Examination of the animal movement and ownership histories of the 56 confirmed positive animals strongly suggested that exogenous beta-NT had been administered at the presenting farm. It is concluded that alpha-NT is not endogenous to this subset of the cattle population and that detection of this hormone in bile from bulls and steers constitutes evidence of abuse. PMID:9990701

  18. 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.

  19. 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

  20. 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

  1. 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.

  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 γ-ray spectrometer. For molluscs, assuming secular equilibrium, the range of activities of 238U (226Ra), 232Th (228Ra) and 40K were found to be 3.28±0.35 to 5.34±0.52, 1.20±0.21 to 2.44±0.21 and 118±6 to 281±14 Bq kg-1 dry weight, respectively. The respective values for crustaceans were 3.02±0.57 to 4.70±0.52, 1.38±0.21 to 2.40±0.35 and 216±11 to 316±15 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 μSv for 226Ra, 19.3 to 39.1 μSv for 228Ra and 17.0 to 40.4 μSv for 40K. For crustaceans, the respective dose ranges are 19.6 to 30.5 μSv, 22.0 to 38.4 μSv and 31.1 to 45.5 μSv, being some several times world average values.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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

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

    PubMed

    Guarín-Zapata, Nicolás; 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

  10. 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

  11. 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.…

  12. 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

  13. 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

  14. 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

  15. 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

  16. 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

  17. 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

  18. 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

  19. 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

  20. 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.

  1. 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.

  2. 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, João 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

  3. Purification of naturally occurring peptides by reversed-phase HPLC.

    PubMed

    Conlon, J Michael

    2007-01-01

    Reversed-phase high performance liquid chromatography (HPLC) has become the method of choice for the purification of peptides and small proteins (M(r) < 10,000 Da) from natural sources. The technique combines high resolution and recovery with ease and speed of operation and is applicable to a wide range of peptides with different physicochemical properties. This protocol describes procedures for (1) the extraction of a biologically active peptide from animal tissue, (2) concentration of the extracts and partial purification on Sep-Pak cartridges, and (3) purification to near homogeneity on a range of silica-based HPLC columns. Standard operating procedures involve acetonitrile as organic modifier, trifluoroacetic acid as ion-pairing reagent and sequential chromatographies on octadecyl (C18), butyl (C4) and diphenyl wide-pore (300 A) columns under gradient elution conditions. The limiting factor in the time taken to isolate a peptide is usually the speed at which assays to detect the peptide can be performed, but purifications can generally be accomplished within 1 or 2 weeks. PMID:17401353

  4. Isolation and Spectral Analysis of Naturally Occurring Thiarubrine A

    NASA Astrophysics Data System (ADS)

    Reyes, Juan; Morton, Melita; Downum, Kelsey; O'Shea, Kevin E.

    2001-06-01

    We have designed an experiment in which students isolate and characterize thiarubrine A, a pseudo-antiaromatic 1,2-dithia-3,5-cyclohexadiene derivative. Thiarubrines are an important class of compounds which have recently received attention because of their unusual reactivity, unique biological activity, and potential medicinal applications. They possess a distinctive red color and structure features that are particularly useful for demonstrating UV-vis, NMR, and IR spectral analyses. A crude mixture containing thiarubrine A is obtained by methanol (liquid-solid) extraction of the roots of short ragweed, Ambrosia artemisiifolia. Alternatively, these compounds can be isolated from numerous taxa within the family Asteraceae. Thiarubrine A possesses alkyl, alkenyl, and alkynyl functionality, which is useful in illustrating the utility of IR and NMR in the characterization of natural products. The long wavelength UV-vis absorption band of thiarubrine is indication of the nonplanarity of dithiin ring and provides an excellent opportunity to discuss the concepts of aromaticity, conjugation, and molecular orbital theory.

  5. 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

  6. 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

  7. 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.

  8. 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

  9. 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

  10. 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.

  11. 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

  12. 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...

  13. CHARACTERIZATION OF CASEINS CROSSLINKED BY A NATURALLY OCCURRING CROSSLINKING AGENT-GENIPIN

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increasing economic and environmental pressures demand more effective utilization of natural resources. Genipin, a naturally occurring crosslinking agent obtained from the fruit of Gardenia jasminoides, has recently attracted much attention due to its low cytotoxicity compared to traditional crossli...

  14. 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 ...

  15. 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

  16. Segregation of naturally occurring mitochondrial DNA variants in a mini-pig model

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Within cells and tissues, the maternally inherited mitochondrial genome (mtDNA) is present in multimeric form and can harbour naturally occurring variants. Whilst high variant load can cause mitochondrial disease, naturally occurring mtDNA variants likely persist at low levels across generations of ...

  17. Technologically Enhanced Naturally Occurring Radioactive Materials (TENORM) in the Oil and Gas Industry: A Review.

    PubMed

    Doyi, Israel; Essumang, David Kofi; Dampare, Samuel; Glover, Eric Tetteh

    2016-01-01

    Radiation is part of the natural environment: it is estimated that approximately 80 % of all human exposure comes from naturally occurring or background radiation. Certain extractive industries such as mining and oil logging have the potential to increase the risk of radiation exposure to the environment and humans by concentrating the quantities of naturally occurring radiation beyond normal background levels (Azeri-Chirag-Gunashli 2004). PMID:26670035

  18. 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,

  19. 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

  20. 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.

  1. 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.

  2. 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...

  3. 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.

  4. Naturally occurring iridoids, secoiridoids and their bioactivity. An updated review, part 3.

    PubMed

    Dinda, Biswanath; Chowdhury, Debashis Roy; Mohanta, Bikas Chandra

    2009-08-01

    Naturally occurring new iridoids and secoiridoids published during 2005-2008 are reviewed with available physical and spectral data: mp, [alpha](D), UV, IR, (1)H- and (13)C-NMR and plant source. The works on biological and pharmacological activity of naturally occurring iridoids and secoiridoids reported during 2005-2008 are also reviewed. Bioactivities like antibacterial, anticancer, anticoagulant, antifungal, anti-inflammatory, antioxidative, antiprotozoal, hepatoprotective and neuroprotective activities are highlighted. PMID:19652401

  5. 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...

  6. 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.

  7. 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.

  8. 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.

  9. Encapsulation of piceatannol, a naturally occurring hydroxylated analogue of resveratrol, by natural and modified cyclodextrins.

    PubMed

    Matencio, Adrián; García-Carmona, Francisco; López-Nicolás, José Manuel

    2016-05-18

    In this work, an in-depth study of the interaction between piceatannol (a type of stilbene with high biological activity) and different natural and modified cyclodextrins (CDs) is made, using steady state fluorescence. This bioactive molecule forms a 1 : 1 complex with all the natural (α-CD, β-CD and γ-CD) and modified (HP-β-CD, HE-β-CD and M-β-CD) CDs tested. Among natural CDs, the interaction of piceatannol with β-CD was the most efficient. However, the modified CDs showed higher encapsulation constants (KF) than β-CD, except M-β-CD; the highest KF being found for HP-β-CD (14 048 ± 702 M(-1)). The encapsulation of piceatannol in the internal cavity of CDs showed a strong dependence on pH and temperature. The interaction between HP-β-CD and piceatannol was less effective in the pH region where the stilbene begins to suffer the deprotonation of its hydroxyl group. Moreover, the values of KF decreased as the system temperature increased. To obtain information on the mechanism involved in the piceatannol affinity for CD, the thermodynamic parameters of the complexation (ΔH°, ΔS° and ΔG°) were studied, the results showed a negative entropy (-3.7 ± 0.2 J mol(-1) K(-1)), enthalpy (-24.6 ± 1.2 kJ mol(-1)) and Gibbs free energy change at 25 °C (-23.5 ± 1.2 J mol(-1)). Finally, molecular docking calculations provided further insights into how the different interactions influence the complexation constant. A high degree of correlation was observed between the computed scores and experimental values. PMID:27142512

  10. 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

  11. 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.

  12. 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

  13. 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

  14. 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

  15. 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 ...

  16. 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…

  17. 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 carcass rinsate could survive in cold or frozen 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...

  18. 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.

    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...

  19. 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...

  1. 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.

  2. Tasks, Teacher Feedback, and Learner Modified Output in Naturally Occurring Classroom Interaction

    ERIC Educational Resources Information Center

    Gurzynski-Weiss, Laura; Revesz, Andrea

    2012-01-01

    Tasks and interactional feedback have received much attention in instructed second language acquisition research in recent years. However, little research exists that has investigated feedback and task factors together during naturally occurring teacher-student interaction in classroom settings. To bridge this gap, the current study explored the…

  3. 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...

  4. 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…

  5. 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...

  6. 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

  7. 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, nature’s 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

  8. Sensitivity, child regulatory processes, and naturally occurring declines in antisocial behavior across childhood.

    PubMed

    Buck, Katharine Ann

    2014-12-01

    Despite considerable research on why antisocial behavior develops and interventions that reduce it, aspects of everyday family processes that may promote naturally occurring declines in antisocial behavior or that may result from such declines in most children without intervention are poorly understood. The current study explored family processes that may enable children to replace antisocial tendencies and the effects that declines in antisocial behavior may have on parenting and child regulatory processes. Longitudinal data from 1,022 children (54 months-6th grade) from the NICHD Study of Early Child Care and Youth Development were examined. Findings demonstrated that naturally occurring declines in antisocial behavior both predicted and were predicted by maternal sensitivity, emotion regulation, and social skills. These declines predicted but were not predicted by declines in hostile attributions. The data revealed multiple indirect paths, which highlight the complex nature of these variables across development. PMID:25221971

  9. 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.

  10. Naturally-occurring osteoarthritis in the domestic rabbit: possible implications for bioengineering research

    PubMed Central

    Arzi, Boaz; Wisner, Erik R.; Huey, Daniel J.; Kass, Philip H.; Hu, Jerry; Athanasiou, Kyriacos A.

    2015-01-01

    Objective Osteoarthritis affects 1 in 8 American adults over the age of 25 and in the US is a leading cause of chronic disability. Therefore, researchers are pursuing investigations on treating this naturally occurring joint disease. Finding the appropriate animal model for translational purposes is of utmost importance. The aim of the present study is to report the occurrence of naturally-occurring osteoarthritis in the domestic rabbit in the context of an appropriate animal model system. Methods A six-year radiographic retrospective study of domestic rabbits was conducted to assess the presence and severity of naturally occurring osteoarthritis in four major joints: the hip, knee, shoulder, and elbow. Results The rabbit experiences radiographic signs of naturally-occurring osteoarthritis. There was a significant influence of age on the development of the disease. Rabbits begin to have radiographic signs of the disease as early as 1 year of age with older rabbits experiencing over 70% occurrence. The most commonly effected joints were the knee and the hip. In addition, there was certain correlation of weight with the occurrence of osteoarthritis. Conclusion Discovery of new osteoarthritis treatment modalities relies on documenting efficacy in a relevant animal model prior to clinical translation. Despite previous claims on the ability of the rabbit’s cartilage to heal spontaneously and readily repair, we demonstrate that radiographically rabbits demonstrate progressive osteoarthritis. We have found that the rabbit is an excellent spontaneously arising model that may allow a predictable translation of results obtained in bioengineering experiments pertaining to the naturally occurring human disease. PMID:22184086

  11. 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.

  12. 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.

  13. Bodily variability of zinc natural isotope abundances in sheep.

    PubMed

    Balter, Vincent; Zazzo, Antoine; Moloney, Aidan P; Moynier, Fred; Schmidt, Olaf; Monahan, Frank J; Albarède, Francis

    2010-03-15

    Evidence is growing that the range of zinc stable isotope compositions, represented by the deviation of (66)Zn in permil units relative to a standard and expressed as delta(66)Zn, is larger in organic matter than in inorganic material. This study reports the variations of delta(66)Zn in various organs of sheep raised on a controlled diet. Zinc was purified by anion-exchange chromatography. The Zn concentrations and Zn stable isotope compositions were determined by quadrupole inductively coupled plasma mass spectrometry and multi-collector inductively coupled plasma mass spectrometry, respectively. The data show that delta(66)Zn variability exceeds 1 per thousand, with bone, muscle, serum and urine enriched in the heavy isotopes, and feces, red blood cells, kidney and liver enriched in light isotopes, all relative to the diet value. The (66)Zn enrichment of the circulating serum reservoir is likely to take place in the digestive tract, probably through the preferential binding of lighter isotopes with phytic acid, which is known to control the uptake of metallic elements. Mass balance calculations suggest that the (66)Zn depletion between diet and feces, which is not balanced by any other outward flux, leads to a secular isotopic drift in serum. A simple time-dependent two-box model, involving the gastro-intestinal tract on the one hand and the muscle and bone on the other, predicts that the maximum (66)Zn enrichment, which equals the difference in delta(66)Zn between diet and bulk (approximately 0.25 per thousand), is reached after about ten years. Therefore, a better understanding of the variations of natural abundance of Zn isotopes in animals and humans will probably bring new perspectives for the assessment of their Zn status. PMID:20155761

  14. 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.

  15. 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.

  16. 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

  17. Magnesium Isotope Fractionation By Chemical Diffusion In Natural Silicate Rocks

    NASA Astrophysics Data System (ADS)

    Chopra, R.; Richter, F. M.; Watson, E. B.

    2009-12-01

    The isotopic composition of geologic materials can be altered by natural processes in a number of different ways. Important information about the conditions and the processes that operated can be documented by studying the resulting fractionations. In this study, we document the fractionation of magnesium isotopes by chemical diffusion between coeval felsic and silicic magmas from the Vinal Cove complex of the Vinalhaven Intrusive Complex in Maine. Further, we show that the isotopic fractionation can be used to determine the extent of diffusive transport associated with particular geological processes. The Vinal Cove complex is dominated by felsic porphyry along with substantial volumes of contemporaneous mafic and hybrid rocks. The rocks of the Vinal Cove complex appear to record events during the waning stages of solidification of the Vinalhaven intrusive complex, when a large mafic dike intruded a small, partially molten inner portion of the mostly solidified, coarse-grained Vinalhaven granite (Wiebe et al., 2004). An approximately 20 cm thick zone of felsic porphyry between granite and basalt is thought to have formed by the thermal rejuvenation of a silicic crystal mush by a basaltic influx. The contact between the porphyry and the basalt is irregular and crenulate. The magnesium isotopic compositions of samples from two regions across this contact were measured. In addition, two experimental diffusion couples, made by juxtaposing powders of felsic porphyry and basalt from the natural sample from Vinal Cove, were also used to quantify and to compare the magnesium isotopic fractionations associated with chemical diffusion between the natural and experimental samples. The two diffusion couples were made by annealing the powders in a piston cylinder assembly at temperatures of 1450°C, pressures of 1450 kbar, and for 22.5 and 10 hours respectively. Chemical diffusion of magnesium from basalt to felsic porphyry was driven by a concentration ratio of between 4 and 5 in diffusion couples and the natural samples and produced a fractionation of 26Mg from 24Mg of between 2-3 ‰ in both, the two diffusion couples and in the two natural samples. The measured isotopic fractionations provide an estimate of the mass dependence of the diffusion coefficients of the magnesium isotopes corresponding to D26Mg/ D24Mg = (24/26)β with β = 0.05. These results correspond with the experimental results and predictions of Richter et al. (2008) and shows that the degree of isotopic fractionation during chemical diffusion depends on the relative mobility of the isotopes (i.e. β) and the concentration contrast between the interdiffusing melts and that its effect is the greatest in the region of low concentration. References Richter F. M., Watson E. B., Mendybaev R. A., Teng F-Z. and Janney P. E. (2008) Magnesium isotope fractionation in silicate melts by chemical and thermal diffusion. Geochem. Cosmochem. Acta 72, 206-220. Wiebe R. A., Manon M. R., Hawkins, D. P. and McDonough W. F. (2004) Late-stage mafic injection and thermal rejuvenation of the Vinalhaven granite, coastal Maine. J. Petrol. Vol. 45, 2133-2153.

  18. The analysis of naturally-occurring radionuclides from uranium and thorium decay series in table mineral waters.

    PubMed

    Aellen, T C; Umbricht, O; Goerlich, W

    1993-03-25

    This project required the highly sensitive analysis of low-level alpha- and beta-emitters naturally occurring in table mineral water sold on the Swiss market. These radionuclides occur in the three major decay series-uranium-238, uranium-235, and thorium-232. The radionuclides analysed were 238U, 235U, 234U, 232Th, 230Th, 228Th, 210Po, 210Pb, and 226Ra. Many other radionuclides were determinable as a result of their equilibrium with an analysed nuclide. Efficient, element specific separation techniques were developed, allowing for the spectral analysis of each element without interference from other radioactive elements. Radioactive tracers, 232U, 230Th, and 209Po, were necessary to determine the percentage yield. These yields often varied greatly between different mineral waters, especially for thorium, ranging from 30 to 100%. Uranium, thorium and polonium isotopes could be directly analysed for by alpha-spectrometry. 226Ra was determined through the ingrowth of its daughter 222Rn by liquid scintillation counting. From the samples remaining after 210Po removal, the isotope's re-ingrowth from 210Pb determined the original 210Pb content. Limits of detection ranged from 0.1 to 2.0 mBq/l. The following contents were determined 234U + 238U 30-720 mBq/l; 232Th + 230Th < 1-5 mBq/l; 228Th 2-40 mBq/l; 226Ra 5-370 mBq/l; 210Po 1-90 mBq/l; 2,0Pb 1-90 mBq/l. PMID:8469952

  19. 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.

  20. 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.)

  1. 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

  2. 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.

  3. Mechanisms and Modifications of Naturally Occurring Host Defense Peptides for Anti-HIV Microbicide Development

    PubMed Central

    Eade, Colleen R.; Wood, Matthew P.; Cole, Alexander M.

    2014-01-01

    Despite advances in the treatment of HIV infection, heterosexual transmission of HIV remains high, and vaccines to prevent HIV acquisition have been unfruitful. Vaginal microbicides, on the other hand, have demonstrated considerable potential for HIV prevention, and a variety of compounds have been screened for their activity and safety as anti-HIV microbicides. Among these are the naturally occurring host defense peptides, small peptides from diverse lineages with intrinsic antiviral activity. Naturally occurring host defense peptides with anti-HIV activity are promising candidates for vaginal microbicide development. Their structural variance and accompanying mechanistic diversity provide a wide range of inhibitors whose antiviral activity can be exerted at nearly every stage of the HIV lifecycle. Additionally, peptide modification has been explored as a method for improving the anti-HIV activity of host defense peptides. Structure- and sequence-based alterations have achieved varying success in improving the potency and specificity of anti-HIV peptides. Overall, peptides have been discovered or engineered to inhibit HIV with therapeutic indices of >1000, encouraging their advancement toward clinical trials. Here we review the naturally occurring anti-HIV host defense peptides, demonstrating their breadth of mechanistic diversity, and exploring approaches to enhance and optimize their activity in order to expedite their development as safe and effective anti-HIV vaginal microbicides. PMID:22264047

  4. 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

  5. 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

  6. Investigating microbial carbon cycling using natural abundance isotope analysis of PLFA

    NASA Astrophysics Data System (ADS)

    Slater, G. G.; Brady, A.; Cowie, B.

    2008-12-01

    Understanding microbial carbon sources and cycling is fundamental to our conceptualization of microbial ecosystems and their role in biogeochemical cycling in natural systems. Achieving this understanding requires application of a wide range of approaches. Natural abundance isotope analysis of individual compounds, particularly cellular components such as Phospholipids Fatty Acids (PLFA) can provide insights into the carbon sources and metabolic activities of the in situ microbial community from environmental samples. This is primarily because specific PLFA can be well resolved by gas chromatography even from complex matrices where confounding biological/organic compound abound. These PLFA can then be attributed to the viable microbial community, in some cases to specific components of this community and due to characteristic biosynthetic fractionations of stable isotope ratios, δ13C analysis of PLFA can: differentiate isotopically distinct primary carbon sources of heterotrophic communities; identify isotopic patterns characteristic of autotrophic versus heterotrophic processes; and elucidate microbial biosynthetic pathways. In cases where there δ13C cannot provide resolution of carbon sources, new approaches in Δ14C of PLFA can be applied. The vast range in Δ14C of ancient and modern carbon provides an easily traceable signal that can differentiate uptake and utilization of these carbon sources. This is particularly useful in cases such as contaminated sites where petroleum based contamination has occurred, or in natural systems where microbial communities may be utilizing geologic versus recently photosynthetically fixed carbon. This talk will present several examples demonstrating the utility of this approach.

  7. Phytohormonal basis for the plant growth promoting action of naturally occurring biostimulators.

    PubMed

    Kurepin, Leonid V; Zaman, Mohammad; Pharis, Richard P

    2014-07-01

    There is increasing interest in the use of naturally occurring 'biostimulators' for enhancing the growth of agricultural and horticultural crops. Bacteria, fungi and protozoa, as well as marine algae-based seaweed extracts, can produce or contain biostimulators. The activity of biostimulators to promote plant growth is often attributed to their ability to directly or indirectly provide mineral nutrients (mostly N, but also P, S and other macro- and micro-nutrients) to plants. Alternatively, biostimulators are postulated to increase the plant's ability to assimilate these mineral nutrients, often in return for photo-assimilates (as occurs with certain bacteria and fungi associations). Although optimal growth of plants depends on the availability of adequate mineral nutritients, that growth (and also development, including reproduction) is also regulated by plant hormones (phytohormones), including gibberellins, auxins and cytokinins. This review describes and discusses the evidence that the presence or application of biostimulators also increases plant growth directly via phytohormone action and also influences the plant's ability to control its own hormone biosynthesis and homeostasis. Finally, it discusses the need for a better understanding of the role(s) that are played by the naturally occurring biostimulators associated with the plant in the crop field. It is suggested that better understanding will allow for optimal crop yield returns, since disruptions of phytohormone homeostasis in plant organs and tissues can yield either beneficial or sub-optimal outcomes. PMID:24375470

  8. 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.

  9. 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.

  10. 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

  11. 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.

  12. 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

  13. Perchlorate isotope forensics with naturally produced 36Cl

    NASA Astrophysics Data System (ADS)

    Hillegonds, D.; Parker, D.; Singleton, M.; Buchholz, B.; Esser, B.; Moran, J.; Rood, D.; Finkel, R.

    2008-12-01

    The source of perchlorate (ClO4-) in many surface and groundwaters is not known. Recent studies (Parker et al., 2008) suggest that natural production is widespread and common, and may involve atmospheric processes. The isotopic composition of perchlorate chlorine and oxygen has proven useful for identifying anthropogenic/natural perchlorate sources (Bohlke et al, 2005) and for exploring biodegradation in environmental samples (Sturchio et al, 2007). The stable isotope approach, however, requires processing very large volumes of water to obtain milligrams of rigorously separated perchlorate for analysis, limiting its widespread application. Chlorine-36 (36Cl) is a long-lived and rare radionuclide produced cosmogenically in the upper atmosphere. The measurement of 36Cl/Cl by accelerator mass spectrometry (AMS) only requires micrograms of sample chlorine enabling lower volume extractions (less than 1/10th that required for stable isotope techniques), and potentially less rigorous perchlorate chemistry. The primary technical goal of our work is to determine the utility of 36Cl in distinguishing perchlorate source and in constraining mechanisms of natural perchlorate formation. We expect that synthetic perchlorate compounds produced using chloride brines from ancient sources and concentrated modern deposits will have low 36Cl/Cl ratios that will be distinct from natural perchlorate produced in the atmosphere. High levels of 36Cl in groundwater or rainwater perchlorate would then be an unambiguous indication of a natural atmospheric production, and the distribution of 36Cl/Cl in precipitation and groundwater (in conjunction with stable isotope compositions) would constrain the mechanism for natural perchlorate production in the atmosphere. Using accelerator mass spectrometry (AMS), we have measured 36Cl/Cl in a number of synthetic perchlorate salts (including potassium, sodium, magnesium, and ammonium salts). Synthetic salt 36Cl/Cl atom ratios range from 1 to 35 e-15 (consistent with recently reported analyses in Sturchio et al., 2008), and are two to fifteen times the AMS background. Bohlke et al, 2005. Anal. Chem. 77, 7838-7842. Parker et al, 2008. Environ. Sci. Technol. 42, 1465-1471. Sturchio et al, 2007. Environ. Sci. Technol. 41, 2796-2802. Sturchio et al, 2008. 36Cl: Tracer of perchlorate origin? (abstr.)Goldschmidt 2008 (July 13-18, Vancouver, Canada). This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344

  14. Kidney transplantation in dogs with naturally occurring end-stage renal disease.

    PubMed

    Mathews, K A; Holmberg, D L; Miller, C W

    2000-01-01

    Renal allografts were performed between unrelated donors and 15 dogs with naturally occurring end-stage renal disease. Donor selection was based on compatible dog erythrocyte antigen typing and cross-matching. An immunosuppressive protocol consisting of rabbit antidog antithymocyte serum, cyclosporin-A, azathioprine, and prednisone was used to control postoperative rejection of the donated kidney. Although seven animals died because of technical failures or rejection episodes, a median survival time of eight months has been achieved, with two dogs living for longer than five years after surgery. Long-term survivors have died from a variety of problems not related to renal allograft rejection. PMID:10914526

  15. Activity measurements of technically enhanced naturally occurring radionuclides (TENORM) in phosphogypsum.

    PubMed

    Luca, A; Margineanu, R; Sahagia, M; Wätjen, A C

    2009-05-01

    Phosphogypsum is a by-product of the phosphoric acid based fertilizer industry; it can be used in agriculture and to make building materials. Phosphogypsum is radioactive due to the presence of technically enhanced naturally occurring radionuclides (TENORM) and its environmental impact is a major concern of the public authorities. The Radionuclide Metrology Laboratory from IFIN-HH participated at the IAEA-CU-2007-06-CCRI(II)-S5 Supplementary Comparison for the Determination of TENORM in phosphogypsum. The measurement procedures and the discussion of results and problems encountered are presented. PMID:19231218

  16. The new IAEA reference material: IAEA-434 technologically enhanced naturally occurring radioactive materials (TENORM) in phosphogypsum.

    PubMed

    Shakhashiro, A; Sansone, U; Wershofen, H; Bollhöfer, A; Kim, C K; Kim, C S; Kis-Benedek, G; Korun, M; Moune, M; Lee, S H; Tarjan, S; Al-Masri, M S

    2011-01-01

    A reliable determination of Technologically Enhanced Naturally Occurring Radioactive Materials in phosphogypsum is necessary to comply with radiation protection and environmental regulations. In this respect, a new phosphogypsum reference material was produced and certified to assist in the validation of analytical methods and the quality assurance of produced analytical results. This paper presents the sample preparation methodology, material homogeneity assessment, characterization campaign results and assignment of property values, and associated uncertainties. The reference values and associated uncertainties for Pb-210, Ra-226, Th-230, U-234 and U-238 were established based on consensus values calculated from analytical results reported by three National Metrology Institutes and five expert laboratories. PMID:20869259

  17. 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.

  18. 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.

  19. Synthesis and anti-cancer activity of naturally occurring 2,5-diketopiperazines.

    PubMed

    Mollica, Adriano; Costante, Roberto; Fiorito, Serena; Genovese, Salvatore; Stefanucci, Azzurra; Mathieu, Veronique; Kiss, Robert; Epifano, Francesco

    2014-10-01

    Three naturally occurring oxyprenylated diketopiperazines were synthesized and preliminarily tested as growth inhibitory agents in vitro against various cancer cell lines. The compounds were tested on six human cancer cell lines with different sensitivity to proapoptotic stimuli using the MTT colorimetric assay. The data revealed that of the chemicals under study only deoxymicelianamide (11) displayed the highest activity, recording mean IC50 growth inhibitory values ranging from 2 to 23 μM. A comparative study with the non-geranylated saturated derivative of (11) revealed the importance of the presence of the geranyloxy side chain and the exocyclic 2,5-DPK double bond moiety for the observed activity. PMID:25064216

  20. 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

  1. 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.

  2. Molecular- and nm-scale Investigation of the Structure and Compositional Heterogeneity of Naturally Occurring Ferrihydrite

    NASA Astrophysics Data System (ADS)

    Cismasu, C.; Michel, F. M.; Stebbins, J. F.; Tcaciuc, A. P.; Brown, G. E.

    2008-12-01

    Ferrihydrite is a hydrated Fe(III) nano-oxide that forms in vast quantities in contaminated acid mine drainage environments. As a result of its high surface area, ferrihydrite is an important environmental sorbent, and plays an essential role in the geochemical cycling of pollutant metal(loid)s in these settings. Despite its environmental relevance, this nanomineral remains one of the least understood environmental solids in terms of its structure (bulk and surface), compositional variations, and the factors affecting its reactivity. Under natural aqueous conditions, ferrihydrite often precipitates in the presence of several inorganic compounds such as aluminum, silica, arsenic, etc., or in the presence of organic matter. These impurities can affect the molecular-level structure of naturally occurring ferrihydrite, thus modifying fundamental properties that are directly correlated with solid-phase stability and surface reactivity. Currently there exists a significant gap in our understanding of the structure of synthetic vs. natural ferrihydrites, due to the inherent difficulties associated to the investigation of these poorly crystalline nanophases. In this study, we combined synchrotron- and laboratory-based techniques to characterize naturally occurring ferrihydrite from an acid mine drainage system situated at the New Idria mercury mine in California. We used high-energy X-ray total scattering and pair distribution function analysis to elucidate quantitative structural details of these samples. We have additionally used scanning transmission X-ray microscopy high resolution imaging (30 nm) to evaluate the spatial relationship of major elements Si, Al, and C within ferrihydrite. Al, Si and C K-edge near- edge X-ray absorption fine structure spectroscopy and 27Al nuclear magnetic resonance spectroscopy were used to obtain short-range structural information. By combining these techniques we attain the highest level of resolution permitted by current analytical methods to study such naturally occurring nanomaterials, both at the molecular- and nm-scale. This work provides structural information at the short-, medium- and long- range, as well as evidence of compositional heterogeneity, and mineral/organic matter associations.

  3. 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.

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

    PubMed Central

    Good, David M.; Zürbig, Petra; Argilés, Àngel; Bauer, Hartwig W.; Behrens, Georg; Coon, Joshua J.; Dakna, Mohammed; Decramer, Stéphane; 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; Neusüss, 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

  5. 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.

  6. Harnessing Naturally Occurring Tumor Immunity: A Clinical Vaccine Trial in Prostate Cancer

    PubMed Central

    Tian, Suyan; Suárez-Fariñas, Mayte; Parveen, Salina; Blachère, Nathalie E.; Morris, Michael J.; Slovin, Susan; Scher, Howard I.; Albert, Matthew L.; Darnell, Robert B.

    2010-01-01

    Background Studies of patients with paraneoplastic neurologic disorders (PND) have revealed that apoptotic tumor serves as a potential potent trigger for the initiation of naturally occurring tumor immunity. The purpose of this study was to assess the feasibility, safety, and immunogenicity of an apoptotic tumor-autologous dendritic cell (DC) vaccine. Methods and Findings We have modeled PND tumor immunity in a clinical trial in which apoptotic allogeneic prostate tumor cells were used to generate an apoptotic tumor-autologous dendritic cell vaccine. Twenty-four prostate cancer patients were immunized in a Phase I, randomized, single-blind, placebo-controlled study to assess the safety and immunogenicity of this vaccine. Vaccinations were safe and well tolerated. Importantly, we also found that the vaccine was immunogenic, inducing delayed type hypersensitivity (DTH) responses and CD4+ and CD8+ T cell proliferation, with no effect on FoxP3+ regulatory T cells. A statistically significant increase in T cell proliferation responses to prostate tumor cells in vitro (p = 0.002), decrease in prostate specific antigen (PSA) slope (p = 0.016), and a two-fold increase in PSA doubling time (p = 0.003) were identified when we compared data before and after vaccination. Conclusions An apoptotic cancer cell vaccine modeled on naturally occurring tumor immune responses in PND patients provides a safe and immunogenic tumor vaccine. (ClinicalTrials.gov number NCT00289341). Trial Registration ClinicalTrials.gov NCT00289341 PMID:20824184

  7. Naturally occurring human urinary peptides for use in diagnosis of chronic kidney disease.

    PubMed

    Good, David M; Zürbig, Petra; Argilés, Angel; Bauer, Hartwig W; Behrens, Georg; Coon, Joshua J; Dakna, Mohammed; Decramer, Stéphane; 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; Neusüss, 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

    2010-11-01

    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

  8. Oocyst Discharge, Rumen Metabolism and Performance of Early Weaned Lambs with Naturally Occurring Coccidiosis Fed Monensin

    PubMed Central

    Horton, G. M. J.; Stockdale, P. H. G.

    1981-01-01

    Ninety-six 9.5 kg early-weaned lambs with naturally occurring coccidiosis were fed monensin either at 0, 11, 22, or 33 mg/kg of feed for 105 days. Fecal oocyst discharge during the first three days was highest with monensin 22 mg, lowest with monensin 33 mg and averaged 149.6 × 103 oocysts per gram feces for all lambs. Monensin at 22 mg/kg of feed reduced Eimeria ninakohlyakimovae and E. ahsata oocyst discharge. Organic matter and crude protein digestibilities were highest (P ≤ 0.05) in lambs fed monensin 22 mg/kg of feed. Monensin increased (P ≤ 0.01) rumen ammonia and propionic acid and decreased (P ≤ 0.01) acetic acid. Feeding monensin 33 mg decreased (P ≤ 0.05) feed intake by 5% and had no effect on gain or feed efficiency. Optimal responses were observed with monensin at 11 mg, feed consumption was not affected, gains were 8% higher (P ≤ 0.05) and feed was utilized 9% more efficiently (P ≤ 0.05) than the controls. In conclusion, monensin was an effective therapeutic agent against naturally occurring coccidial infections in early weaned lambs. Performance responses were largest with monensin fed at the rate of 11 mg/kg of feed. PMID:7197187

  9. 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

  10. 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

  11. Community responses to naturally occurring asbestos: implications for public health practice.

    PubMed

    Culley, M R; Zorland, J; Freire, K

    2010-10-01

    We used a qualitative community case study design to examine stakeholder responses to naturally occurring asbestos (NOA), a newly emerging environmental threat. The community of interest represents the first residential setting in the United States to receive substantial federal, state and local regulatory attention where NOA exposures largely resulted from local development. Because NOA is an emerging problem that will require evidence-based public health responses in the United States and elsewhere, we explored stakeholder responses to NOA and examined how these responses fit with what is known about individual, community and institutional responses to environmental hazards. The convergence of findings from multiple data sources, including interviews with stakeholder groups and documents, revealed a myriad of challenges associated with environmental and public health interventions in this community. What unfolded was consistent with the social sciences literature about communities facing similar hazards. 'Natural' and 'human-made' elements, the toxic nature of the threat and inadequate institutional responses to the threat combined to spark community conflict and other significant challenges. Implications for improved public health practice are discussed. PMID:20643707

  12. 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% (δ44/42Ca) on <25 μg 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.

  13. AB254. DU145: a naturally occurring cell with ATG5-independent alternative macroautophagy

    PubMed Central

    Qiu, Wei; Tian, Ye

    2016-01-01

    Background Autophagy serves as a catabolic pathway to maintain cellular homeostasis. The role of autophagy in cancer cells is essential for supplying adequate substrates for proliferation and metabolism. Recent study identified DU145, different from LNCaP and PC-3 cells, was an autophagy-deficient cell line due to the deficiency of ATG5 protein. However, ATG5-independent alternative macroautophagy has already been discovered in ATG5 knockout mouse embryo fibroblasts. In this study, our goal is to discover whether DU145 is a naturally occurring cell with such an alternative autophagy. Methods The lipidation levels of microtubule-associated protein 1 light chain 3 (LC3) was detected by Western blotting. Cultured cells were transfected with the GFP-LC3 expressing plasmid and the fluorescence was viewed using confocal microscopy. Ultrastructure was observed using transmission electron microscopy. Immuno-electron microscopy was performed to determine the co-location of LC3 and autophagic vacuoles. Results Under basal condition, the lipidation form of LC3, known as LC3-II, is detectable in both PC-3 and LNCaP cells. Stimulating autophagy with rapamycin or blocking autophagosome degradation with chloroquine increased the LC3-II levels in these cell lines. In contrast, LC3-II is constitutively undetectable in DU145 cells even treated with rapamycin or chloroquine. Similarly, the formation of autophagosome indicated by GFP-LC3 punctate was not easily observed in DU145 treated with rapamycin or chloroquine. Interestingly, we observed a great number of intracellular autophagic vacuoles under electron microscopy in all of three cell lines after starvation. Immuno-electron microscopy was applied with primary antibodies against LC3. Autophagic vacuoles labeled well with antibody against LC3-II in both PC-3 and LNCaP cells, rather than DU145 cells. These results suggested that DU145 is a naturally occurring cell with ATG5-independent autophagy. Conclusions Our findings reveal that DU145 is a naturally occurring cell with an ATG5-independent alternative autophagy, which indicates a novel category of tumor cells may exists in prostate cancer patients.

  14. 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

  15. 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

  16. Some Nutritional Characteristics of a Naturally Occurring Alga (Microcystis sp.) in a Guatemalan Lake.

    PubMed

    de la Fuente, G; Flores, A; Molina, M R; Almengor, L; Bressani, R

    1977-01-01

    The nutritional characteristics of an alga (Microcystis sp.) that occurs naturally in a Guatemalan lake were determined. The sun-dried material proved to have a high protein content (55.6%) and to be a possible good source of calcium and phosphorus (1, 169.1 and 633.4 mg/100 mg, respectively). Amino acid analysis showed that total sulfur amino acids were the most deficient ones, giving a protein score of 42 to the material. The in vitro protein digestibility of the material was 69.5%. Biological trials demonstrated that when the material was offered as the only protein source, very low consumption and a high mortality rate were obtained whether or not the diet was supplemented with 0.4% dl-methionine. However, when the material supplied 25% of the total protein of a corn-algae diet, the protein quality of the cereal was significantly improved (P < 0.05). PMID:16345191

  17. 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

  18. Some Nutritional Characteristics of a Naturally Occurring Alga (Microcystis sp.) in a Guatemalan Lake

    PubMed Central

    de la Fuente, Gabriel; Flores, Antonio; Molina, Mario R.; Almengor, Leticia; Bressani, Ricardo

    1977-01-01

    The nutritional characteristics of an alga (Microcystis sp.) that occurs naturally in a Guatemalan lake were determined. The sun-dried material proved to have a high protein content (55.6%) and to be a possible good source of calcium and phosphorus (1, 169.1 and 633.4 mg/100 mg, respectively). Amino acid analysis showed that total sulfur amino acids were the most deficient ones, giving a protein score of 42 to the material. The in vitro protein digestibility of the material was 69.5%. Biological trials demonstrated that when the material was offered as the only protein source, very low consumption and a high mortality rate were obtained whether or not the diet was supplemented with 0.4% dl-methionine. However, when the material supplied 25% of the total protein of a corn-algae diet, the protein quality of the cereal was significantly improved (P < 0.05). PMID:16345191

  19. 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

  20. 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

  1. 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.

  2. Naturally occurring Parelaphostrongylus tenuis-associated choriomeningitis in a guinea pig with neurologic signs.

    PubMed

    Southard, T; Bender, H; Wade, S E; Grunenwald, C; Gerhold, R W

    2013-05-01

    An adult male guinea pig (Cavia porcellus) with a 1-month history of hind limb paresis, torticollis, and seizures was euthanized and submitted for necropsy. Gross examination was unremarkable, but histologic examination revealed multifocal eosinophilic and lymphoplasmacytic choriomeningitis and cross sections of nematode parasites within the leptomeninges of the midbrain and diencephalon. Morphologic features of the nematode were consistent with a metastrongyle, and the parasite was identified as Parelaphostrongylus tenuis by polymerase chain reaction testing and nucleotide sequencing. Further questioning of the owner revealed that the guinea pig was fed grass from a yard often grazed by white-tailed deer (Odocoileus virginianus). To the authors' knowledge, this is the first report of a naturally occurring P. tenuis infection in a guinea pig. PMID:23238578

  3. 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

  4. 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.

  5. 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.

  6. General and Stereocontrolled Approach to the Chemical Synthesis of Naturally Occurring Cyanogenic Glucosides.

    PubMed

    Møller, Birger L; Olsen, Carl E; Motawia, Mohammed S

    2016-04-22

    An effective method for the chemical synthesis of cyanogenic glucosides has been developed as demonstrated by the synthesis of dhurrin, taxiphyllin, prunasin, sambunigrin, heterodendrin, and epiheterodendrin. O-Trimethylsilylated cyanohydrins were prepared and subjected directly to glucosylation using a fully acetylated glucopyranosyl fluoride donor with boron trifluoride-diethyl etherate as promoter to afford a chromatographically separable epimeric mixture of the corresponding acetylated cyanogenic glucosides. The isolated epimers were deprotected using a triflic acid/MeOH/ion-exchange resin system without any epimerization of the cyanohydrin function. The method is stereocontrolled and provides an efficient approach to chemical synthesis of other naturally occurring cyanogenic glucosides including those with a more complex aglycone structure. PMID:26959700

  7. Naturally occurring radioactive materials (NORM): a matter of wide societal implication.

    PubMed

    Pescatore, C; Menon, S

    2000-12-01

    Naturally occurring radioactive materials are ubiquitous on Earth and their radioactivity may become concentrated as a result of human activities. Numerous industries produce concentrated radioactivity in their by-products: the coal industry, petroleum extraction and processing, water treatment, etc. The present reference system of radiation protection does not provide a complete framework for the coherent management of all types of radioactively contaminated materials. Inconsistencies in waste management policy and practice can be noted across the board, and especially vis-à-vis the management of radioactive waste from the nuclear industry. This article reviews the present societal approach to manage materials that are radioactive but are often not recognised as being such, and place the management of radioactive materials from the nuclear industry in perspective. PMID:11302258

  8. 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

  9. 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.

  10. 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.

  11. Partitioning of naturally-occurring radionuclides (NORM) in Marcellus Shale produced fluids influenced by chemical matrix.

    PubMed

    Nelson, Andrew W; Johns, Adam J; Eitrheim, Eric S; Knight, Andrew W; Basile, Madeline; Bettis Iii, E Arthur; Schultz, Michael K; Forbes, Tori Z

    2016-04-20

    Naturally-occurring radioactive materials (NORM) associated with unconventional drilling produced fluids from the Marcellus Shale have raised environmental concerns. However, few investigations into the fundamental chemistry of NORM in Marcellus Shale produced fluids have been performed. Thus, we performed radiochemical experiments with Marcellus Shale produced fluids to understand the partitioning behavior of major radioelements of environmental health concern (uranium (U), thorium (Th), radium (Ra), lead (Pb), and polonium (Po)). We applied a novel radiotracer, (203)Pb, to understand the behavior of trace-levels of (210)Pb in these fluids. Ultrafiltration experiments indicated U, Th, and Po are particle reactive in Marcellus Shale produced fluids and Ra and Pb are soluble. Sediment partitioning experiments revealed that >99% of Ra does not adsorb to sediments in the presence of Marcellus Shale produced fluids. Further experiments indicated that although Ra adsorption is related to ionic strength, the concentrations of heavier alkaline earth metals (Ba, Sr) are stronger predictors of Ra solubility. PMID:26952871

  12. 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

  13. Leishmanicidal and cytotoxic activities of extracts and naturally-occurring compounds from two Lauraceae species.

    PubMed

    Sánchez-Suárez, Jeysson; Coy-Barrera, Ericsson; Cuca, Luis Enrique; Delgado, Gabriela

    2011-02-01

    The in vitro leishmanicidal effects of ethanolic extracts and fifteen naturally-occurring compounds (five lignans, eight neolignans, a diterpene and a dihydrochalcone), obtained from Pleurothyrium cinereum and Ocotea macrophylla, were evaluated on promastigotes of Leishmania panamensis and L. braziliensis. In addition, in order to determine the selective action on Leishmania species as a safety principle, in vitro cytotoxicity on J774 cells was also evaluated for test compounds and extracts. One extract and seven compounds showed activity against Leishmania parasites at different levels. Dihydroflavokawin B (8) was found to be the most potent antileishmanial compound on both parasites, whilst (+)-otobaphenol (14), was found to be the most selective compound on L. panamensis. PMID:21425681

  14. 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

  15. 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, Graça; 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

  16. 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

  17. 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

  18. The effect of inoculum volume on the microbiologic detection of naturally occurring Staphylococcus aureus intramammary infections.

    PubMed

    Walker, Jennifer B; Rajala-Schultz, Päivi J; DeGraves, Fred J

    2010-09-01

    Currently no standard definitions for the diagnosis of Staphylococcus aureus intramammary infection (IMI) exist. As a result, criteria applied in research to diagnose S. aureus IMIs have varied making comparisons between published works difficult. The goal of the current study was to define the optimal inoculum volume used in the diagnosis of naturally occurring S. aureus IMIs. Microbiologic results from 2 field studies examining S. aureus IMIs were used to examine the effects of inoculum volume on the microbiologic detection of S. aureus. A total of 1,583 milk samples were included in the analysis, and the results of using a 0.01-ml and a 0.1-ml inoculum are presented. Using a 0.01-ml inoculum resulted in a sensitivity of 91% (95% confidence interval [CI]: 88.6-93%) and a specificity of 99.4% (95% CI: 98.6-99.8%). Using the larger 0.1-ml inoculum resulted in a sensitivity of 96.8% (95% CI: 95.2-97.9%) and a specificity of 99.3% (95% CI: 98.4-99.7%). All false-positive samples were from S. aureus-negative quarters in S. aureus-positive cows. There were no false-positive cultures from S. aureus-negative cows. Of the false-negative samples, the majority (77%) were from 6 of the 34 S. aureus-positive quarters. Results from the current study of naturally occurring S. aureus IMIs support the hypothesis that, when using quarter level milk samples, a S. aureus IMI is most accurately diagnosed using a 0.1-ml inoculum. Regardless of inoculum volume, a single quarter sample culture that is positive with S. aureus (>or=1 colony-forming unit) is sufficient to diagnose a S. aureus IMI. PMID:20807927

  19. 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

  20. 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

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

    PubMed

    Gurden, Mark D; Westwood, Isaac M; Faisal, Amir; Naud, Sébastien; 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

  2. Glycosphingolipid analysis in a naturally occurring ovine model of acute neuronopathic Gaucher disease.

    PubMed

    Karageorgos, Litsa; Hein, Leanne; Rozaklis, Tina; Adams, Melissa; Duplock, Stephen; Snel, Marten; Hemsley, Kim; Kuchel, Tim; Smith, Nicholas; Hopwood, John J

    2016-07-01

    Gaucher disease arises from mutations in the β-glucocerebrosidase gene which encodes an enzyme required for the lysosomal catabolism of glucosylceramide. We have identified a naturally occurring mutation in the β-glucocerebrosidase gene in sheep that leads to Gaucher disease with acute neurological symptoms. Here we have examined the clinical phenotype at birth and subsequently quantified lipids in Gaucher lamb brain, in order to characterise the disorder. Enzyme activity assessments showed that a reduction in β-glucocerebrosidase activity to 1-5% of wild-type occurs consistently across newborn Gaucher lamb brain regions. We analyzed glucosylceramide, glucosylsphingosine, bis(monoacylglycero)phosphate and ganglioside profiles in brain, liver, and spleen, and observed 30- to 130-fold higher glucosylceramide, and 500- to 2000-fold higher glucosylsphingosine concentrations in Gaucher diseased lambs compared to wild-type. Significant increases of bis(monoacylglycero)phosphate and gangliosides [GM1, GM2, GM3] concentrations were also detected in the brain. As these glycosphingolipids are involved in many cellular events, an imbalance or disruption of the cell membrane lipid homeostasis would be expected to impair normal neuronal function. To our knowledge, this is the first detailed analysis of glycosphingolipids in various brain regions in a large animal model of neuronal disease, which permits the mechanistic investigation of lipid deregulation and their contribution to neurodegenerative process. PMID:26976737

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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.

  13. Potential health risk in areas with high naturally-occurring cadmium background in southwestern China.

    PubMed

    Liu, Yizhang; Xiao, Tangfu; Baveye, Philippe C; Zhu, Jianming; Ning, Zengping; Li, Huajun

    2015-02-01

    In various parts of the world, high cadmium (Cd) concentrations in environment are not related to anthropogenic contamination but have natural origins. Less is known about health risks that arise under these conditions. This study aimed to discuss the pollution of Cd with natural sources, and to investigate the concentration of Cd in food crops and the urine of inhabitants in an area of southwestern China. The results showed that the arable soils are moderately contaminated by Cd (I(geo)=1.51) relative to the local background, with a high ecological risk (Er=218). The chemical fractions of Cd in soils with natural sources are probably controlled by parent materials and mostly in residual phase. The average Cd concentrations were 0.68 mg kg(-1) (fresh weight) in local vegetables, 0.04 mg kg(-1) in rice, and 0.14 μg L(-1) in water. Leafy vegetable tends to accumulate more Cd than the other crops. The calculated Target Hazard Quotient (THQ) had a much higher value (4.33) for Cd, suggesting that Cd represents a significant potential risk to the local population. The urinary Cd concentrations (mean at 3.92 μg L(-1) for male and 4.85 μg L(-1) for female) of inhabitants in the study area were significantly higher (p<0.05) than those from the control area (mean at 0.8 μg L(-1) for male and 0.42 μg L(-1) for female). Male and female test subjects had similar urinary Cd levels (p>0.05), but age seemed to lead to an increase in Cd in the urine. These findings show that naturally-occurring Cd in local soils is taken up appreciably by local food crops, and that dietary exposure of Cd through vegetable ingestion is a major exposure pathway for local populations, and a potential risk to public health in the study area. PMID:25463862

  14. 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.

  15. 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

  16. Early and delayed effects of naturally occurring asbestos on serum biomarkers of inflammation and metabolism.

    PubMed

    Kodavanti, Urmila P; Andrews, Debora; Schladweiler, Mette C; Gavett, Stephen H; Dodd, Darol E; Cyphert, Jaime M

    2014-01-01

    Studies recently showed that intratracheal (IT) instillation of Libby amphibole (LA) increases circulating acute-phase proteins (APP; α-2 macroglobulin, A2M; and α-1 acid glycoprotein, AGP) and inflammatory biomarkers (osteopontin and lipocalin) in rats. In this study, objectives were to (1) compare changes in biomarkers of rats after instillation of different naturally occurring asbestos (NOA) minerals including LA, Sumas Mountain chrysotile (SM), El Dorado Hills tremolite (ED), and Ontario ferroactinolite cleavage fragments (ON), and (2) examine biomarkers after subchronic LA or amosite inhalation exposure. Rat-respirable fractions (aerodynamic diameter approximately 2.5 μm) prepared by water elutriation were delivered via a single IT instillation at doses of 0, 0.5, and 1.5 mg/rat in male F344 rats. Nose-only inhalation exposures were performed at 0, 1, 3.3, and 10 mg/m(3) for LA and at 3.3 mg /m(3) for amosite, 6h/d, 5 d/wk for 13 wk. Inflammation, metabolic syndrome, and cancer biomarkers were analyzed in the serum for up to 18 mo. IT instillation of some asbestos materials significantly increased serum AGP and A2M but to a varying degree (SM = LA > ON = ED). Numerical increases in interleukin (IL)-6 and osteopontin occurred in rats instilled with SM. SM and ED also elevated leptin and insulin at 15 mo, suggesting potential metabolic effects. LA inhalation tended to raise A2M at d 1 but not cytokines. Serum mesothelin appeared to elevate after 18 mo of LA inhalation. These results suggest that the lung injury induced by high levels of asbestos materials may be associated with systemic inflammatory changes and predisposition to insulin resistance. PMID:25072823

  17. 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.

  18. 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

  19. 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.

  20. 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.

  1. 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.

  2. 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

  3. 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

  4. 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.

  5. Persistence of naturally occurring antibiotic resistance genes in the bacteria and bacteriophage fractions of wastewater.

    PubMed

    Calero-Cáceres, William; Muniesa, Maite

    2016-05-15

    The emergence and prevalence of antibiotic resistance genes (ARGs) in the environment is a serious global health concern. ARGs from bacteria can be mobilized by mobile genetic elements, and recent studies indicate that phages and phage-derived particles, among others, could play a role in the spread of ARGs through the environment. ARGs are abundant in the bacterial and bacteriophage fractions of water bodies and for successful transfer of the ARGs, their persistence in these environments is crucial. In this study, three ARGs (blaTEM, blaCTX-M and sul1) that naturally occur in the bacterial and phage fractions of raw wastewater were used to evaluate the persistence of ARGs at different temperatures (4 °C, 22 °C and 37 °C) and pH values (3, 7 and 9), as well as after various disinfection treatments (thermal treatment, chlorination and UV) and natural inactivation in a mesocosm. Gene copies (GC) were quantified by qPCR; then the logarithmic reduction and significance of the differences between their numbers were evaluated. The ARGs persisted for a long time with minimal reductions after all the treatments. In general, they showed greater persistence in the bacteriophage fraction than in the bacterial fraction. Comparisons showed that the ARGs persisted under conditions that reduced culturable Escherichia coli and infectious coliphages below the limit of detection. The prevalence of ARGs, particularly in the bacteriophage fraction, poses the threat of the spread of ARGs and their incorporation into a new bacterial background that could lead to the emergence of new resistant clones. PMID:26978717

  6. 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

  7. Potential involvement of Neospora caninum in naturally occurring ovine abortions in New Zealand.

    PubMed

    Howe, L; Collett, M G; Pattison, R S; Marshall, J; West, D M; Pomroy, W E

    2012-04-30

    Neospora caninum is an obligate intracellular parasite and is recognised as the leading cause of bovine abortion worldwide. Natural infection with N. caninum has been described in sheep but it has generally not been regarded as a significant cause of abortion. Recently, there have been several New Zealand cases of foetal abortions where N. caninum was detected which strongly suggested the involvement of Neospora in these abortions. However, there is minimal information about the prevalence of N. caninum infection naturally occurring in New Zealand sheep flocks and particularly its impact on reproduction success. Thus, this present study provides preliminary data on the role that Neospora is playing in ovine reproductive failure by establishing the prevalence of N. caninum antibodies and DNA in ewe blood and foetal material present in 21 New Zealand sheep farms with ongoing unexplained abortion problems and 10 farms with consistently high fertility levels. The results of this study demonstrated an overall seroprevalence of 1.4% which varied between Aborting/non-pregnant (1.8%), age-matched pregnant controls (0.6%) and high fertility (2.1%) ewes. However, despite the variation observed, there was no statistical difference between the three groups. In addition, Neospora DNA was detected by PCR in 13% of submitted foetal brains and in ewe blood from aborting/non-pregnant (6.9%), age-matched pregnant controls (3.6%) and high fertility pregnant (2.1%) ewes. When the PCR results were considered with the IFAT and IDEXX ELISA results, there was no correlation between serology positive and PCR positive blood samples. Taken together, these results reveal that reliance on ELISA-based serology or PCR alone may underestimate the involvement of Neospora. Furthermore, determining the involvement of Neospora appears to require a multi-facetted approach where diagnostic methods and serological cut-off values may need to be adjusted as further information about the effect of natural infections with N. caninum in the ovine host is elucidated. PMID:22112976

  8. Genetic basis of hindlimb loss in a naturally occurring vertebrate model

    PubMed Central

    Don, Emily K.; de Jong-Curtain, Tanya A.; Doggett, Karen; Hall, Thomas E.; Heng, Benjamin; Badrock, Andrew P.; Winnick, Claire; Nicholson, Garth A.; Guillemin, Gilles J.; Currie, Peter D.; Hesselson, Daniel; Heath, Joan K.; Cole, Nicholas J.

    2016-01-01

    ABSTRACT Here we genetically characterise pelvic finless, a naturally occurring model of hindlimb loss in zebrafish that lacks pelvic fin structures, which are homologous to tetrapod hindlimbs, but displays no other abnormalities. Using a hybrid positional cloning and next generation sequencing approach, we identified mutations in the nuclear localisation signal (NLS) of T-box transcription factor 4 (Tbx4) that impair nuclear localisation of the protein, resulting in altered gene expression patterns during pelvic fin development and the failure of pelvic fin development. Using a TALEN-induced tbx4 knockout allele we confirm that mutations within the Tbx4 NLS (A78V; G79A) are sufficient to disrupt pelvic fin development. By combining histological, genetic, and cellular approaches we show that the hindlimb initiation gene tbx4 has an evolutionarily conserved, essential role in pelvic fin development. In addition, our novel viable model of hindlimb deficiency is likely to facilitate the elucidation of the detailed molecular mechanisms through which Tbx4 functions during pelvic fin and hindlimb development. PMID:26892237

  9. 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

  10. Bismuth solubility through binding by various organic compounds and naturally occurring soil organic matter.

    PubMed

    Murata, Tomoyoshi

    2010-01-01

    The present study was performed to examine the effects of soluble organic matter and pH on the solubility of Bi in relation to inference with the behavior of metallic Bi dispersed in soil and water environments using EDTA, citric acid, tartaric acid, L-cysteine, soil humic acids (HA), and dissolved organic matter (DOM) derived from the soil organic horizon. The solubility of Bi by citric acid, tartaric acid, L-cysteine, HA, and DOM showed pH dependence, while that by EDTA did not. Bi solubility by HA seemed to be related to the distribution of pKa (acid dissociation constant) values of acidic functional groups in their molecules. That is, HA extracted at pH 3.2 solubilized Bi preferentially in the acidic range, while HA extracted at pH 8.4 showed preferential solubilization at neutral and alkaline pH. This was related to the dissociation characteristics of functional groups, their binding capacity with Bi, and precipitation of Bi carbonate or hydroxides. In addition to the dissociation characteristics of functional groups, the unique structural configuration of the HA could also contribute to Bi-HA complex formation. The solubility of Bi by naturally occurring DOM derived from the soil organic horizon (Oi) and its pH dependence were different from those associated with HA and varied among tree species. PMID:20390922

  11. 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

  12. 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.

  13. 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

  14. 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

  15. 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.

  16. 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

  17. SUPPLEMENTARY COMPARISON Technically enhanced naturally occurring radionuclides (TENORM) in phosphogypsum: Comparison CCRI(II)-S5

    NASA Astrophysics Data System (ADS)

    Shakhashiro, A.; Sansone, U.; Wershofen, H.; Bollhöfer, A.; Kim, C. K.; Kim, C. S.; Korun, M.; Moune, M.; Lee, S. H.; Tarjan, S.

    2010-01-01

    Within the frame of mutual cooperation between the IAEA and the BIPM, the Consultative Committee for Ionizing Radiation Section II—Measurement of Radionuclides accepted an IAEA-organized interlaboratory comparison in 2008 on the determination of technically enhanced naturally occurring radionuclides in phosphogypsum. The study was piloted by the Chemistry Unit at the IAEA's Laboratories in Seibersdorf (Austria). This report presents the methodology applied in conducting this comparison and the results. Activity results for Pb-210, Ra-226, Th-230, U-234, U-235 and U-238 were reported by three national metrology institutes (NMI) and five other expert laboratories or designated institutes. Four different approaches were used to calculate the nominal value of the reported results and associated uncertainties, and the results from each individual participant were evaluated and compared with this nominal reference value. The reported evaluation of the measurement results demonstrated agreement amongst the participating laboratories. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI Section II, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

  18. 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.

  19. 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

  20. 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

  1. Pre-concentration of naturally occurring radionuclides and the determination of (212)Pb from fresh waters.

    PubMed

    Burnett, J L; Croudace, I W; Warwick, P E

    2011-04-01

    A novel technique has been developed for determining the (212)Pb activity of fresh waters. This is of interest to environmental monitoring programmes that utilise gross α-activity methods to screen for anthropogenic radionuclides. The contribution from (212)Pb varies, and is difficult to experimentally measure due to its relatively short half-life (t(½) = 10.6 h) and low environmental activity (<0.1 Bq l(-1)). The use of a three-stage technique that encompasses a unique form of pre-concentration, separation and analysis by liquid scintillation counting allows a lower detection limit of 0.006 Bq l(-1) with a chemical yield of 92.5 ± 5.6%. The measurement can be obtained within 7 h of sample collection, and is calculated using the radioactive decay of (212)Bi. Other naturally occurring radionuclides may also be extracted using the pre-concentration stage of the technique, with efficiencies above 90% at a range of pH values. PMID:21306802

  2. 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.

  3. 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

  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. 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

  6. Genetic basis of hindlimb loss in a naturally occurring vertebrate model.

    PubMed

    Don, Emily K; de Jong-Curtain, Tanya A; Doggett, Karen; Hall, Thomas E; Heng, Benjamin; Badrock, Andrew P; Winnick, Claire; Nicholson, Garth A; Guillemin, Gilles J; Currie, Peter D; Hesselson, Daniel; Heath, Joan K; Cole, Nicholas J

    2016-01-01

    Here we genetically characterise pelvic finless, a naturally occurring model of hindlimb loss in zebrafish that lacks pelvic fin structures, which are homologous to tetrapod hindlimbs, but displays no other abnormalities. Using a hybrid positional cloning and next generation sequencing approach, we identified mutations in the nuclear localisation signal (NLS) of T-box transcription factor 4 (Tbx4) that impair nuclear localisation of the protein, resulting in altered gene expression patterns during pelvic fin development and the failure of pelvic fin development. Using a TALEN-induced tbx4 knockout allele we confirm that mutations within the Tbx4 NLS (A78V; G79A) are sufficient to disrupt pelvic fin development. By combining histological, genetic, and cellular approaches we show that the hindlimb initiation gene tbx4 has an evolutionarily conserved, essential role in pelvic fin development. In addition, our novel viable model of hindlimb deficiency is likely to facilitate the elucidation of the detailed molecular mechanisms through which Tbx4 functions during pelvic fin and hindlimb development. PMID:26892237

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

    PubMed

    Rocha, Martha S T; Lucci, Carolina M; Longo, João Paulo F; Galera, Paula D; Simioni, Andreza R; Lacava, Zulmira G M; Tedesco, Antônio 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

  8. 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.

  9. 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

  10. Differential modulation of the genotoxicity of food carcinogens by naturally occurring monomeric and dimeric polyphenolics.

    PubMed

    Catterall, F; Souquet, J M; Cheynier, V; de Pascual-Teresa, S; Santos-Buelga, C; Clifford, M N; Ioannides, C

    2000-01-01

    Naturally occurring dimeric polyphenolics and their gallate esters were isolated from grape seeds, almond fruits, and apple skin, and their ability to modulate the mutagenicity of food carcinogens was studied in the Ames test, and compared to that of the monomeric green tea flavonols, (+)-catechin and (-)-epicatechin. Neither the monomeric nor the dimeric polyphenols and their galloylated derivatives influenced the mutagenic activity elicited by the indirectly acting food carcinogens benzo[a]pyrene and 2-amino-3-methylimidazo-[4,5-f]quinoline (IQ), in the presence of a hepatic activation system derived from Aroclor 1254-treated rats; the only exception was the B7 dimer, which, at concentrations above 1 microM, suppressed the mutagenicity of IQ. None of the polyphenolics modulated the mutagenic activity elicited by the directly acting carcinogen N'-methyl-N'-nitro-nitrosoguanidine (MNNG). In contrast, all the dimeric polyphenols and the galloylated metabolites, at concentrations over 1 microM, potentiated the mutagenic activity induced by the indirectly acting carcinogen N-nitrosopyrrolidine, in the presence of an activation system derived from isoniazid-treated rats. In conclusion, dimeric polyphenols and galloylated derivatives of plant origin are unlikely to influence the initiation stage of the carcinogenicity of chemicals through mechanisms that involve inhibition of their cytochrome P450-mediated bioactivation or scavenging of the reactive, genotoxic intermediates. PMID:10712742

  11. 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

  12. 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.

  13. 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

  14. 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

  15. 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

  16. 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.

  17. 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

  18. The effects of naturally occurring acids on the surface properties of chrysotile asbestos.

    PubMed

    Holmes, Emma P; Lavkulich, L M Les

    2014-01-01

    Chrysotile asbestos is considered an environmental health hazard. It is postulated that the surface of chrysotile, with its inherent positive charge and chemical content of trace transition metals within the mineral is a causative factor of the concern. Weathering may reduce the negative health effects of chrysotile asbestos, by alteration of the outer brucite layer of the chrysotile. To assess the changes in the surface properties of chrysotile asbestos by simulated weathering, chrysotile was treated with oxalic, hydrochloric, and carbonic acids. Naturally occurring chrysotile, from a mine site and serpentinitic stream sediments from the Sumas River were analyzed and compared. Oxalic acid, a chelating acid, was the most effective at extracting the majority of the trace elements present in the chrysotile, reducing their positive surface charge and producing visible changes at the surface of the fibers as shown by Field Emission Scanning Electron Microsopy (FESEM). Carbonic acid had little effect on the surface properties. Stream environments had minor detectable effects on the surface properties on the chrysotile stream sediments. PMID:25072777

  19. Theoretical simulations on the antioxidant mechanism of naturally occurring flavonoid: A DFT approach

    NASA Astrophysics Data System (ADS)

    Praveena, R.; Sadasivam, K.

    2016-05-01

    Synthetic antioxidants such as butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) are found to be toxic, hence non-carcinogenic naturally occurring radical scavengers especially flavonoids have gained considerable importance in the past two decades. In the present investigation, the radical scavenging activity of C-glycosyl flavonoids is evaluated using theoretical approach which could broaden its scope in therapeutic applications. Gas and solvent phase studies of structural and molecular characteristics of C-glycosyl flavonoid, isovitexin is investigated through hydrogen atom transfer mechanism (HAT), Electron transfer-proton transfer (ET-PT) and Sequential proton loss electron transfer (SPLET) by Density functional theory (DFT) using hybrid parameters. The computed values of the adiabatic ionization potential, electron affinity, hardness, softness, electronegativity and electrophilic index indicate that isovitexin possess good radical scavenging activity. The behavior of different -OH groups in polyphenolic compounds is assessed by considering electronic effects of the neighbouring groups and the overall geometry of molecule which in turn helps in analyzing the antioxidant capacity of the polyphenolic molecule. The studies indicate that the H-atom abstraction from 4'-OH site is preferred during the radical scavenging process. From Mulliken spin density analysis and FMOs, B-ring is found to be more delocalized center and capable of electron donation. Comparison of antioxidant activity of vitexin and isovitexin leads to the conclusion that isovitexin acts as a better radical scavenger. This is an evidence for the importance of position of glucose unit in the flavonoid.

  20. 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.

  1. 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

  2. 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

  3. 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

  4. 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...

  5. 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.

  6. 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...

  7. Isotopic composition and neutronics of the Okelobondo natural reactor

    NASA Astrophysics Data System (ADS)

    Palenik, Christopher Samuel

    The Oklo-Okelobondo and Bangombe uranium deposits, in Gabon, Africa host Earth's only known natural nuclear fission reactors. These 2 billion year old reactors represent a unique opportunity to study used nuclear fuel over geologic periods of time. The reactors in these deposits have been studied as a means by which to constrain the source term of fission product concentrations produced during reactor operation. The source term depends on the neutronic parameters, which include reactor operation duration, neutron flux and the neutron energy spectrum. Reactor operation has been modeled using a point-source computer simulation (Oak Ridge Isotope Generation and Depletion, ORIGEN, code) for a light water reactor. Model results have been constrained using secondary ionization mass spectroscopy (SIMS) isotopic measurements of the fission products Nd and Te, as well as U in uraninite from samples collected in the Okelobondo reactor zone. Based upon the constraints on the operating conditions, the pre-reactor concentrations of Nd (150 ppm +/- 75 ppm) and Te (<1 ppm) in uraninite were estimated. Related to the burnup measured in Okelobondo samples (0.7 to 13.8 GWd/MTU), the final fission product inventories of Nd (90 to 1200 ppm) and Te (10 to 110 ppm) were calculated. By the same means, the ranges of all other fission products and actinides produced during reactor operation were calculated as a function of burnup. These results provide a source term against which the present elemental and decay abundances at the fission reactor can be compared. Furthermore, they provide new insights into the extent to which a "fossil" nuclear reactor can be characterized on the basis of its isotopic signatures. In addition, results from the study of two other natural systems related to the radionuclide and fission product transport are included. A detailed mineralogical characterization of the uranyl mineralogy at the Bangombe uranium deposit in Gabon, Africa was completed to improve geochemical models of the solubility-limiting phase. A study of the competing effects of radiation damage and annealing in a U-bearing crystal of zircon shows that low temperature annealing in actinide-bearing phases is significant in the annealing of radiation damage.

  8. 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.

  9. 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.

  10. Zinc and cadmium adsorption to aluminum oxide nanoparticles affected by naturally occurring ligands.

    PubMed

    Stietiya, M Hashem; Wang, Jim J

    2014-03-01

    Nanoparticles of aluminum oxide (AlO) are efficient in removing Cd, Zn, and other heavy metals from wastewaters and soil solutions due to their high specific surface area and surface area to volume ratio. Naturally occurring ligands, such as phosphate (PO), citrate, and humic acid (HA), may affect the efficiency of AlO nanoparticles in adsorption of Cd and Zn. The objective of this study was to investigate Zn and Cd adsorption to AlO nanoparticles as influenced by PO, citrate, and HA. Adsorption of Zn and Cd was performed in mono-metal and binary-metal systems at pH 6.5 with initial metal concentration of 1.0 mmol L and varying ligand concentration at a solid:solution ratio of 1:1000. Adsorption isotherms showed that Zn had higher affinity to the AlO nanoparticle surface than Cd and that adsorption of Zn and Cd in the binary-metal system was lower than in the respective mono-metal systems. Phosphate and HA enhanced Zn and Cd adsorption in all systems, whereas citrate reduced Zn adsorption in the mono-metal system by 25% and increased adsorption in the other metal systems. Removal of Zn or Cd from the systems was generally accompanied by enhanced removal of PO and HA, which may indicate enhanced adsorption due to ternary complex formation or metal-ligand precipitation. Phosphate was the most effective among the three ligands in enhancing Zn and Cd adsorption. Overall, AlO nanoparticles are suitably used for Zn and Cd adsorption, which can be significantly enhanced by the presence of PO or HA and to a lesser degree by citrate at low concentrations. PMID:25602651

  11. 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

  12. 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.

  13. Wetland defense: naturally occurring pesticide resistance in zooplankton populations protects the stability of aquatic communities.

    PubMed

    Bendis, Randall J; Relyea, Rick A

    2016-06-01

    Anthropogenic stressors are ubiquitous and have been implicated in worldwide declines of terrestrial and aquatic species. Pesticides are one such stressor that can have profound effects on aquatic communities by directly affecting sensitive species and indirectly affecting other species via trophic cascades, which can alter ecosystem function. However, there is growing evidence that non-target species can evolve increased resistance. When such species are important drivers of the food web, then evolved resistance should help buffer communities from the effects of pesticides. To examine this possibility, we cultured four populations of the common zooplankton Daphnia pulex that we previously demonstrated were either sensitive or resistant to a common insecticide (i.e., chlorpyrifos) due to their proximity to agriculture. Using outdoor mesocosms that contained identical aquatic communities of phytoplankton, periphyton, and leopard frog tadpoles (Lithobates pipiens), we manipulated four D. pulex populations and four insecticide concentrations. As we monitored the communities for nearly 3 months, we found that the insecticide caused direct mortality of D. pulex in communities containing sensitive populations, and this led to a bloom of phytoplankton. In contrast, the insecticide caused much less direct mortality in communities containing resistant D. pulex populations, and the trophic cascade was prevented under low to moderate insecticide concentrations. Across all insecticide treatments, survivorship of leopard frogs was approximately 72 % in communities with resistant D. pulex but only 35 % in communities with sensitive D. pulex. To our knowledge, this is one of the first studies to use naturally occurring population variation in insecticide resistance to show that the evolution of pesticide resistance in zooplankton can mitigate the effects of insecticide-induced trophic cascades, and that this outcome can have far-reaching community effects. PMID:26875187

  14. 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 biodegradation–cis-dichloroethene (cis-DCE) and chloride–using 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.

  15. 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. PMID:26467890

  16. 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

  17. 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

  18. 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

  19. 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

  20. 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.; Patrocínio, 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 réparation des radicaux oxydés de l'adénine et de la guanosine par des xanthines naturelles a été étudiée en soumettant chaque paire base de l'ADN/xanthine à l'oxydation par le radical sulfate et en mesurant par HPLC la disparition des deux composés en fonction du temps d'irradiation. Les résultats montrent que la xanthine joue un rôle protecteur efficace contre l'oxydation des deux purines de l'ADN. La théophyline et la paraxanthine réparent le radical oxydé de l'adénine mais pas celui de la guanosine. La théobromine et la cafeíne n'ont pas d'effet protecteur. Un ordre de potentiels d'oxydation des purines étudiées est proposé.

  1. Cerebrospinal Fluid Inflammatory Cytokines and Chemokines in Naturally Occurring Canine Spinal Cord Injury

    PubMed Central

    Taylor, Amanda R.; Welsh, C. Jane; Young, Colin; Spoor, Erich; Kerwin, Sharon C.; Griffin, John F.; Levine, Gwendolyn J.; Cohen, Noah D.

    2014-01-01

    Abstract Canine intervertebral disk herniation (IVDH) is a common, naturally occurring form of spinal cord injury (SCI) that is increasingly being used in pre-clinical evaluation of therapies. Although IVDH bears critical similarities to human SCI with respect to lesion morphology, imaging features, and post-SCI treatment, limited data are available concerning secondary injury mechanisms. Here, we characterized cerebrospinal fluid (CSF) cytokines, and chemokines in dogs with acute, surgically treated, thoracolumbar IVDH (n=39) and healthy control dogs (n=21) to investigate early inflammatory events after SCI. A bioplex system was used to measure interleukin (IL)-2, -6, -7, -8, -10, -15, and -18, granulocyte macrophage colony-stimulating factor (GM-CSF), interferon gamma (IFN-γ), keratinocyte chemoattractant (KC)-like protein, IFN-γ-inducible protein-10, monocyte chemotactic protein 1 (MCP-1), and tumor necrosis factor alpha. Cytokine and chemokine concentrations in the CSF of healthy and SCI dogs were compared and, in SCI dogs, were correlated to the duration of SCI, behavioral measures of injury severity at the time of sampling, and neurological outcome 42 days post-SCI as determined by a validated ordinal score. IL-8 concentration was significantly higher in SCI cases than healthy controls (p=0.0013) and was negatively correlated with the duration of SCI (p=0.042). CSF MCP-1 and KC-like protein were positively correlated with CSF microprotein concentration in dogs with SCI (p<0.0001 and p=0.004). CSF MCP-1 concentration was negatively associated with 42-day postinjury outcome (p<0.0001). Taken together, these data indicate that cytokines and chemokines present after SCI in humans and rodent models are associated with SCI pathogenesis in canine IVDH. PMID:24786364

  2. 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

  3. 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

  4. Determination of naturally occurring MTBE biodegradation by analysing metabolites and biodegradation by-products.

    PubMed

    Martienssen, Marion; Fabritius, Holger; Kukla, Stefan; Balcke, Gerd U; Hasselwander, Eyk; Schirmer, Mario

    2006-09-10

    Methyl tert-butyl ether (MTBE) is one of the main additives in gasoline. Its degradation is known to be difficult in natural environments. In this study, significant MTBE degradation is demonstrated at a contaminated site in Leuna (eastern Germany). Since the extent of the plume appeared to be constant over the last 5 years, an extended study was performed to elucidate the degradation processes. Special attention was paid to the production, accumulation and degradation of metabolites and by-products. Groundwater samples from 105 monitoring wells were used to measure 20 different substances. During the degradation process, several intermediates such as tert-butyl alcohol (TBA), tert-butyl formate, formate and lactate were produced. However, the potentially carcinogenic by-product methacrylate was not detected in several hundred samples. At the Leuna site, MTBE degradation occurred under microaerobic conditions. In contrast to hydrocarbons and BTEX, there was no evidence for anaerobic MTBE degradation. Among the degradation products, TBA was found to be a useful intermediate to identify MTBE degradation, at least under microaerobic conditions. TBA accumulation was strongly correlated to MTBE degradation according to the kinetic properties of both degradation processes. Since maximum degradation rates (v(max)) and k(m) values were higher for MTBE (v(max)=2.3 mg/l/d and k(m)=3.2 mg/l) than for TBA (v(max)=1.35 mg/l/d and k(m)=0.05 mg/l), TBA significantly accumulated as an intermediate by-product. The field results were supported by bench scale model aquifer experiments. PMID:16828928

  5. 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...

  6. Selection of Naturally Occurring Extended-Spectrum TEM β-Lactamase Variants by Fluctuating β-Lactam Pressure

    PubMed Central

    Blazquez, Jesús; Morosini, María-Isabel; Negri, María-Cristina; Baquero, Fernando

    2000-01-01

    Despite the large number of in vitro mutations that increase resistance to extended-spectrum cephalosporins in TEM-type β-lactamases, only a small number occur in naturally occurring enzymes. In nature, and particularly in the hospital, bacteria that contain β-lactamases encounter simultaneous or consecutive selective pressure with different β-lactam molecules. All variants obtained by submitting an Escherichia coli strain that contains a blaTEM-1 gene to fluctuating challenge with both ceftazidime and amoxicillin contained only mutations previously detected in naturally occurring β-lactamases. Nevertheless, some variants obtained by ceftazidime challenge alone contained mutations never detected in naturally occurring TEM β-lactamases, suggesting that extended-spectrum TEM variants in hospital isolates result from fluctuating selective pressure with several β-lactams rather than selection with a single antibiotic. PMID:10898697

  7. 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

  8. 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

  9. 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

  10. 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

  11. 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 μM 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.

  12. Elevated Bacterial Abundance in Laboratory-Grown and Naturally Occurring Frost Flowers Under Late Winter Conditions

    NASA Astrophysics Data System (ADS)

    Bowman, J. S.; Deming, J. W.

    2009-12-01

    Sea ice has been identified as an important microbial habitat, with bacteria and other microbes concentrated in the brine inclusions between ice crystals. Frost flowers, thought to draw brine from underlying sea ice, have not been characterized from a microbial standpoint. To test whether frost flowers serve as an upward vector of bacteria contained within sea ice brines we grew frost flowers in a freezer laboratory (air temperature of -21°C) from saline water spiked with the mesophilic (and thus passive under experimental conditions) bacterium Halomonas pacifica. Salinity of melted samples was measured and bacterial abundance determined by epifluorescent microscopy. Bacterial counts scaled to ice-melt volume averaged 2.82 x 106 ml-1 for frost flowers, compared to 9.47 x 105 ml-1 for underlying ice (3 x higher). Bacterial counts also correlated significantly with salinity (maximum value of 62.5 psu) for frost flowers, brine skim, and ice (df = 17, r = 0.59, p < 0.0001). Segregation coefficients were calculated to describe the efficiency of transport of both cells and salt from the starting solution into frost flowers. From these coefficients an enrichment index was calculated to test for bacterial concentration into frost flowers at a different rate than salt. Analysis with a Student’s T-test (df = 24, t = 0.306, p = .76) indicated that cells and salt were not transported into frost flowers with a significantly different efficiency. To test these findings in the field we then collected frost flowers (and related samples) from new sea ice near Barrow, Alaska in April 2009. Bacterial counts were significantly elevated (again, a 3-fold increase) in natural frost flowers (mean = 2.73 x 105 ml-1) compared to underlying sea ice (mean = 8.46 x 104 cells ml-1). For all field samples collected (frost flowers, underlying brine skim and sea ice, as well as snow), bacterial abundance correlated significantly with salinity (maximum value 124 psu, df = 40, r = 0.60, p < 0.0001). The presence of elevated numbers of bacteria in frost flowers may have implications for the previously observed chemical reactions that take place in them, especially if microbial activity can be shown to occur in this unique low temperature, low water activity microbial habitat.

  13. 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

  14. 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

  15. 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

  16. 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

  17. Effects of feeding a high omega-3 fatty acids diet in dogs with naturally occurring osteoarthritis.

    PubMed

    Moreau, M; Troncy, E; Del Castillo, J R E; Bédard, C; Gauvin, D; Lussier, B

    2012-07-14

    The aim of this randomized, placebo-controlled and double-blinded trial was to compare the effect of a veterinary therapeutic diet (VTD) rich in omega-3 fatty acids (omega-3) from fish origin to a regular diet used as control (CTR) over a period of 13 weeks in dogs afflicted by naturally occurring osteoarthritis (OA). Thirty privately owned dogs were selected. Dogs had lameness confirmed by an orthopaedic examination, had stifle/hip OA and had locomotor disability based on the peak of the vertically oriented ground reaction force (PVF) measured using a force platform. At Baseline, all owners were asked to determine 2-5 activities of daily living that were the most impaired. Activities were scores (0-4) in accordance with severity using case-specific outcome measures (CSOM). The PVF was also measured. Dogs (15/group) were then randomly assigned to receive either the CTR or the VTD. The CSOM was completed twice weekly. The recording of PVF was repeated at Week 7 and 13. The VTD-fed dogs showed a significantly higher PVF at Week 7 (p < 0.001) and at Week 13 (p < 0.001) when compared to Baseline. From Baseline to Week 13, VTD-fed dogs had a mean (± SD) change in PVF recording of 3.5 ± 6.8% of body weight (%BW) compared with 0.5 ± 6.1%BW (p = 0.211) in CTR-fed dogs. This change in primary outcome was consistent with an effect size of 0.5. Conversely, dogs fed the CTR did not show significant change in PVF measurements. At the end of the study, the CSOM was significantly decreased (p = 0.047) only in VTD fed dogs. In lame OA dogs, a VTD that contains high level of omega-3 from fish origin improved the locomotor disability and the performance in activities of daily living. Such nutritional approach appears interesting for the management of OA. PMID:22805303

  18. 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.

  19. 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.

  20. Mortality of one-week-old chickens during naturally occurring Marek's disease virus infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Marek’s 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...

  1. 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

  2. The effect of natural weathering on the chemical and isotopic compositions of biotites

    USGS Publications Warehouse

    Clauer, Norbert; O'Neil, J.R.; Bonnot-Courtois, C.

    1982-01-01

    The effect of progressive natural weathering on the isotopic (Rb-Sr, K-Ar, ??D, ??18O) and chemical (REE, H2O+) compositions of biotite has been studied on a suite of migmatitic biotites from the Chad Republic. During the early stages of weathering the Rb-Sr system is strongly affected, the hydrogen and oxygen isotope compositions change markedly, the minerals are depleted in light REE, the water content increases by a factor of two, and the K-Ar system is relatively little disturbed. During intensive weathering the K-Ar system is more strongly disturbed than the Rb-Sr system. Most of the isotopic and chemical modifications take place under nonequilibrium conditions and occur before newly formed kaolinite and/or smectite can be detected. These observations suggest that 1. (a) "protominerals" may form within the biotite structure during the initial period of weathering, and 2. (b) only when chemical equilibrium is approached in the weathering profile are new minerals able to form. ?? 1982.

  3. 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 ...

  4. Multi-Isotope Analysis as a Natural Reaction Probe of Biodegradation Mechanisms of 1,2- Dichloroethane

    NASA Astrophysics Data System (ADS)

    Hirschorn, S. K.; Dinglasan-Panlilio, M.; Edwards, E. A.; Lacrampe-Couloume, G.; Sherwood Lollar, B.

    2006-12-01

    1,2-Dichloroethane (1,2-DCA), a chlorinated aliphatic hydrocarbon, is an EPA priority pollutant and a widespread groundwater contaminant. Stable isotope fractionation during biodegradation of 1,2-DCA occurs due to differences in the reaction rates of heavy versus light atoms present at a reacting bond in the 1,2-DCA molecule. In general, light isotopic bonds react more quickly, producing a relative enrichment in the heavy isotope in the remaining contaminant pool. Compound specific isotope analysis has the potential to demonstrate the occurrence and extent of biodegradation at chlorinated solvent contaminated groundwater sites. In this study, stable carbon isotope fractionation was used as a novel reaction probe to provide information about the mechanism of 1,2-DCA biodegradation. Isotopic fractionation was measured during 1,2-DCA degradation by a microbial culture capable of degrading 1,2-DCA under O2-reducing and NO3-reducing conditions. The microbial culture produced isotopic enrichment values that are not only large and reproducible, but are the same whether O2 or NO3 was used as an electron acceptor. The mean isotopic enrichment value of -25.8 permil measured for the microbial culture during 1,2-DCA degradation under both O2 and NO3- reducing conditions can be converted into a kinetic isotope effect (KIE) value to relate the observed isotopic fractionation to the mechanism of degradation. This KIE value (1.05) is consistent with degradation via a hydrolysis (SN2) reaction under both electron-accepting conditions. Isotope analysis was able to provide a first line of evidence for the reaction mechanism of 1,2-DCA biodegradation by the microbial culture. Using a multi-isotope approach incorporating both carbon and hydrogen isotopic data, compound specific isotope analysis also has the potential to determine degradation mechanisms for 1,2-DCA under aerobic conditions where 1,2-DCA is known to be degraded by two distinct enzymatic pathways. Biodegradation of 1,2-DCA via a hydrolysis (SN2) reaction produces a large carbon isotope enrichment (isotopic enrichment factor = -29.2 permil) while oxidation of 1,2-DCA via a monooxygenase enzyme produces a small carbon isotope enrichment (isotopic enrichment factor = -3.9 permil). Conversely, because a hydrogen bond is not broken in the hydrolysis (SN2) reaction, only a small secondary hydrogen isotope enrichment is expected, while a large hydrogen isotope enrichment is expected during oxidation of 1,2-DCA via a monooxygenase enzyme. The complementary information of both carbon and hydrogen isotopic data may be instrumental in identifying the mechanism of biodegradation in the subsurface, and illustrates the potential of compound specific isotope analysis as a natural reaction probe to provide insight into the enzymatic mechanism of subsurface contaminant degradation.

  5. 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.

  6. 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.

  7. The naturally occurring furanones: formation and function from pheromone to food.

    PubMed

    Colin Slaughter, J

    1999-08-01

    Three closely related 4-hydroxy-3(2H)-furanones have been found in a range of highly cooked foodstuffs where they are important flavour compounds with aroma threshold values as low as 20 micrograms kg-1 water (approximately 0.14 mumol l-1). The compounds are formed mainly as a result of the operation of the Maillard reactions between sugars and amino acids during heating but one compound, 5-(or 2)-ethyl-2-(or 5)-methyl-4-hydroxy-3(2H)-furanone, appears in practice to be produced by yeast, probably from a Maillard intermediate, during the fermentation stages in the production of soy sauce and beer. The compounds are also important in the flavour of strawberry, raspberry, pineapple and tomato but the route of biosynthesis is unknown. Two 3-hydroxy-2(5H)-furanones, emoxyfuranone and sotolon, which are produced spontaneously from amino acids such as threonine and 4-hydroxy-L-leucine are major contributors to meaty and spicy/nutty flavours in foods. The biosynthesis of 5-(1,2-dihydroxyethyl)-3,4-dihydroxy-2(5H)-furanone (ascorbic acid, vitamin C) and 5-hydroxymethyl-3,4-dihydroxy-2(5H)-furanone (erythroascorbic acid) from sugars in plants and yeast, respectively, has been characterized to the enzymic level. After treatment with chlorine, humic waters contain a range of chloro-furanones, some of which, particularly 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX), are powerful mutagens. The furanones which occur in foods are also mutagenic to bacteria and cause DNA damage in laboratory tests. However, these compounds are, in practice, very effective anti-carcinogenic agents in the diets of animals which are being treated with known cancer-inducing compounds such as benzo[alpha]pyrene or azoxymethane. Two of the food-derived furanones have antioxidant activity comparable to that of ascorbic acid. A biological function has been discovered for some of the furanones besides vitamin C. 5-Methyl-4-hydroxy-3(2H)-furanone is a male pheromone in the cockroach Eurycolis florionda (Walker) and the 2,5-dimethyl derivative deters fungal growth on strawberries and is an important component of the attractive aroma of the fruit. The red seaweed Delisea pulchra (Greville) Montagne produces a range of brominated furanones which prevent colonisation of the plant by bacteria by interfering with the acylated homoserine lactone (AHL) signalling system used by the bacteria for quorum sensing. In addition, these compounds can deter grazing by marine herbivores. It is proposed here that the evolved biological function of a number of furanones is to act as inter-organism signal molecules in several different systems. This has resulted in two coincidental effects which are important for humans. Firstly, the easily oxidized nature of the furanones in general, which is likely to be an important property in their functioning as signal molecules, results in both mutagenic and anti-carcinogenic activity. The balance of these two effects from compounds in the diet has yet to be fully established. Secondly, and more specifically, the 4-hydroxy-3(2H)-furanones associated with fruit aromas act to attract animals to the fruit, which ensures seed dispersal. In the case of humans, the coincidental synthesis of some of these compounds in foods during preparation results in these foods appearing particularly attractive through the transferred operation of the original signalling mechanisms. PMID:10466251

  8. Nitrate dynamics in natural plants: insights based on the concentration and natural isotope abundances of tissue nitrate.

    PubMed

    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: δ(18)O and Δ(17)O); 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 δ(18)O-NO(-) 3 variation, and summarize the uncertainties in using tissue NO(-) 3 parameters to interpret plant NO(-) 3 utilization. PMID:25101106

  9. 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

  10. Review of research on impacts to biota of discharges of naturally occurring radionuclides in produced water to the marine environment.

    PubMed

    Hosseini, Ali; Brown, Justin E; Gwynn, Justin P; Dowdall, Mark

    2012-11-01

    Produced water has been described as the largest volume waste stream in the exploration and production process of oil and gas. It is accompanied by discharges of naturally occurring radionuclides raising concerns over the potential radiological impacts of produced water on marine biota. In the Northern European marine environment, radioactivity in produced water has received substantial attention owing to the OSPAR Radioactive Substances Strategy which aims at achieving 'concentrations in the environment near background values for naturally occurring radioactive substances'. This review provides an overview of published research on the impacts to biota from naturally occurring radionuclides discharged in produced water by the offshore oil and gas industry. In addition to summarising studies and data that deal directly with the issue of dose and effect, the review also considers studies related to the impact of added chemicals on the fate of discharged radionuclides. The review clearly illustrates that only a limited number of studies have investigated possible impacts on biota from naturally occurring radionuclides present in produced water. Hence, although these studies indicate that the risk to the environment from naturally occurring radionuclides discharged in produced water is negligible, the substantial uncertainties involved in the assessments of impact make it difficult to be conclusive. With regard to the complexity involved in the problem under consideration there is a pressing need to supplement existing data and acquire new knowledge. Finally, the present work identifies some knowledge gaps to indicate future research requirements. PMID:23022586

  11. 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...

  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. First report of the natural occurence of Tomato chlorotic spot virus in peanuts in Haiti

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tomato chlorotic spot virus (TCSV) was identified in peanut in Haiti. This is the first report of TCSV naturally infecting peanut. Genetic diversity of TCSV was characterized. This report provides an overview of this emerging virus for growers, extension workers, crop consultants and research and...

  14. 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.

  15. A naturally occurring nanomaterial from the Sundew (Drosera) for tissue engineering.

    PubMed

    Lenaghan, S C; Serpersu, K; Xia, L; He, W; Zhang, M

    2011-12-01

    In recent years advances have been made in the design of novel materials for tissue engineering through the use of polysaccharides. This study evaluated the ability of a naturally secreted polysaccharide adhesive from the Sundew (Drosera capensis) as a support for cell growth. The Sundew adhesive has several advantages including its high elasticity and antibiotic nature. By coating glass cover slips with the Sundew adhesive, a network of nanofibers was generated that was capable of promoting attachment and differentiation of a model neuronal cell line, PC-12. We also demonstrated the potential of this material for repairing bone and soft tissue injuries, by testing attachment of osteoblasts and endothelial cells. Finally, it was determined that the Sundew biomaterial was stable through testing by atomic force microscopy and prolonged cell growth. This work has proven the capabilities of using a nanomaterial derived from the Sundew adhesive for the purpose of tissue engineering. PMID:22064887

  16. Modulation of sickle cell crisis by naturally occurring band 3 specific antibodies -- a malaria link.

    PubMed

    Kennedy, James Randall

    2002-05-01

    This paper's focus is prevention of sickle cell adhesion resulting from the erythrocyte's prematurely denatured hemoglobin. This denatured hemoglobin causes a molecule called band 3 to cluster on the erythrocyte's surface and adhere to the CD36 molecule located on the microvascular endothelium. Natural antibodies recognize these clusters on senescent erythrocytes and prevent their endothelial adhesion and target them for reticuloendothelial elimination. Band 3 is also displayed on the erythrocytes of individuals with falciparum malaria and the vaso-occlusive pathology in these patients is prevented in individuals with sickle trait. The hypothesis is that prematurely denatured sickle hemoglobin results in an up regulation of natural antibodies which control erythrocyte adhesion in both malaria and sickle cell disease. PMID:12011759

  17. 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

  18. 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

  19. 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

  20. Weakly electric fish display behavioral responses to envelopes naturally occurring during movement: implications for neural processing.

    PubMed

    Metzen, Michael G; Chacron, Maurice J

    2014-04-15

    How the brain processes natural sensory input remains an important and poorly understood problem in neuroscience. The efficient coding hypothesis asserts that the brain's coding strategies are adapted to the statistics of natural stimuli in order to efficiently process them, thereby optimizing their perception by the organism. Here we examined whether gymnotiform weakly electric fish displayed behavioral responses that are adapted to the statistics of the natural electrosensory envelopes. Previous studies have shown that the envelopes resulting from movement tend to consist of low (<1 Hz) temporal frequencies and are behaviorally relevant whereas those resulting from social interactions consist of higher (>1 Hz) temporal frequencies that can thus mask more behaviorally relevant signals. We found that the self-generated electric organ discharge frequency follows the detailed time course of the envelope around a mean value that is positively offset with respect to its baseline value for temporal frequencies between 0.001 Hz and 1 Hz. The frequency-following component of this behavioral response decreased in magnitude as a power law as a function of the envelope frequency and was negligible for envelope frequencies above 1 Hz. In contrast, the offset component was relatively constant and somewhat increased for envelope frequencies above 1 Hz. Thus, our results show that weakly electric fish display behavioral responses that track the detailed time course of low but not high frequency envelope stimuli. Furthermore, we found that the magnitude of the frequency-following behavioral response matches, in a one-to-one fashion, the spectral power of natural second-order stimulus attributes observed during movement. Indeed, both decayed as a power law with the same exponent for temporal frequencies spanning three orders of magnitude. Thus, our findings suggest that the neural coding strategies used by weakly electric fish perceive the detailed time course of movement envelopes and are adapted to their statistics as found in the natural environment. They also suggest that weakly electric fish might take advantage of the differential frequency content of movement and social envelopes in order to give appropriate behavioral responses during encounters between two or more conspecifics. PMID:24363423

  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. 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

  3. The Role of Neoantigens in Naturally Occurring and Therapeutically Induced Immune Responses to Cancer.

    PubMed

    Ward, Jeffrey P; Gubin, Matthew M; Schreiber, Robert D

    2016-01-01

    Definitive experimental evidence from mouse cancer models and strong correlative clinical data gave rise to the Cancer Immunoediting concept that explains the dual host-protective and tumor-promoting actions of immunity on developing cancers. Tumor-specific neoantigens can serve as targets of spontaneously arising adaptive immunity to cancer and thereby determine the ultimate fate of developing tumors. Tumor-specific neoantigens can also function as optimal targets of cancer immunotherapy against established tumors. These antigens are derived from nonsynonymous mutations that occur during cellular transformation and, because they are foreign to the host genome, are not subject to central tolerance. In this review, we summarize the experimental evidence indicating that cancer neoantigens are the source of both spontaneously occurring and therapeutically induced immune responses against cancer. We also review the advances in genomics, bioinformatics, and cancer immunotherapy that have facilitated identification of neoantigens and have moved personalized cancer immunotherapies into clinical trials, with the promise of providing more specific, safer, more effective, and perhaps even more generalizable treatments to cancer patients than current immunotherapies. PMID:26922999

  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. 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

  7. 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

  8. A non-intrusive velocity measurement technique for naturally-occurring turbulent shear flows

    NASA Astrophysics Data System (ADS)

    Ng, Chin Hei; Keedy, Ryan; Aliseda, Alberto

    2013-11-01

    Turbulent shear flows are common in nature (atmospheric low level jets, ocean hydrothermal vents, volcanic eruptions, convective cells, etc) and play an important role in environmental processes. These frequently inaccessible and measurements that require a physical probe are both restricted and inaccurate. We propose a non-intrusive technique that estimates the velocity of these flows by taking advantage of the existence of natural markers, such as condensation droplets, gas bubbles, reflective turbulent features on the mixing interface, that can be observed in video of the phenomena. Displacement of these markers, assumed to behave as fluid material elements, is measured by digital image correlation, and that velocity is associated with the fluid superlayer at the mixing interface between the ``seeded'' and unseeded flows. The relationship between these superficial velocities and the velocity in the interior of the flow has been investigated in a turbulent round jet laboratory experiment that allows for variations in jet Reynolds number, jet density, and jet viscosity. Influence of imaging parameters was also studied, with particular relevance to the application of this technique to the field.

  9. Phenylpropanoids as naturally occurring antioxidants: from plant defense to human health.

    PubMed

    Korkina, L G

    2007-01-01

    Phenylpropanoids (PPs) belong to the largest group of secondary metabolites produced by plants, mainly, in response to biotic or abiotic stresses such as infections, wounding, UV irradiation, exposure to ozone, pollutants, and other hostile environmental conditions. It is thought that the molecular basis for the protective action of phenylpropanoids in plants is their antioxidant and free radical scavenging properties. These numerous phenolic compounds are major biologically active components of human diet, spices, aromas, wines, beer, essential oils, propolis, and traditional medicine. Last few years, much interest has been attracted to natural and synthetic phenylpropanoids for medicinal use as antioxidant, UV screens, anticancer, anti-virus, anti-inflammatory, wound healing, and antibacterial agents. They are of great interest for cosmetic and perfume industries as active natural ingredients. In the present review, the metabolic pathways of phenylpropanoid biosynthesis in plants and the mechanism of phenylpropanoid-mediated plant defense are described. Learning from plants, free radical-driven, molecular and cellular processes modulated by phenylpropanoids in human cell cultures in vitro and in the in vivo animal models of tumors, inflammation, and cellular damage are also reviewed. PMID:17519109

  10. Climate change enhances the mobilisation of naturally occurring metals in high altitude environments.

    PubMed

    Zaharescu, Dragos G; Hooda, Peter S; Burghelea, Carmen I; Polyakov, Viktor; Palanca-Soler, Antonio

    2016-08-01

    Manmade climate change has expressed a plethora of complex effects on Earth's biogeochemical compartments. Climate change may also affect the mobilisation of natural metal sources, with potential ecological consequences beyond mountains' geographical limits; however, this question has remained largely unexplored. We investigated this by analysing a number of key climatic factors in relationship with trace metal accumulation in the sediment core of a Pyrenean lake. The sediment metal contents showed increasing accumulation trend over time, and their levels varied in step with recent climate change. The findings further revealed that a rise in the elevation of freezing level, a general increase in the frequency of drier periods, changes in the frequency of winter freezing days and a reducing snow cover since the early 1980s, together are responsible for the observed variability and augmented accumulation of trace metals. Our results provide clear evidence of increased mobilisation of natural metal sources - an overlooked effect of climate change on the environment. With further alterations in climate equilibrium predicted over the ensuing decades, it is likely that mountain catchments in metamorphic areas may become significant sources of trace metals, with potentially harmful consequences for the wider environment. PMID:27093125

  11. Rapid formation of N-nitrosodimethylamine from gramine, a naturally occurring precursor in barley malt.

    PubMed

    Mangino, M M; Scanlan, R A

    1984-01-01

    The two tertiary amine alkaloids, hordenine and gramine, which are biosynthesized in malt during germination, were subjected to nitrosation under conditions typical for the study of tertiary amine nitrosation. At 65 degrees C in dilute aqueous acid (pH 4.4 or pH 6.4), nitrosation of both amines resulted in formation of N-nitrosodimethylamine (NDMA). At 24 degrees C in dilute acid (pH 3.4), the initial rate of NDMA formation from gramine was nearly equal to the initial rate of NDMA formation from dimethylamine. At the same temperature, the ratio of initial rates of formation of NDMA from gramine and trimethylamine was 6250:1. At 23 degrees C, the ratio of initial rates of formation of NDMA from gramine and hordenine was 5200:1. The rapid reaction of gramine with nitrous acid and the nature of the gramine nitrosation reaction products both indicated that gramine did not undergo nitrosation by the expected mechanism of nitrosative dealkylation. A new mechanism if proposed to explain the labile nature of the dimethylamino group of gramine and to account for the fact that NDMA is the only N-nitrosamine formed during the nitrosation of gramine. PMID:6533024

  12. Fate and bioaccumulation of soil-associated low-level naturally occurring radioactivity following disposal into a marine ecosystem. Final report

    SciTech Connect

    Hunt, C.D.

    1986-10-01

    The fate of radium (Ra) and other naturally occurring uranium-series isotopes associated with soils disposed in seawater was examined using the Marine Ecosystem Research Laboratory (MERL) controlled marine ecosystems. Thirty-seven kilograms of a soil containing approximately 400 pCi Ra-226/g from an inactive uranium ore processing plant site in Middlesex, New Jersey, were added to each of two mesocosms over five days in mid-September 1984. Radionuclide activity in these and two control mesocosms was observed for three months after the soil additions. Radioactivity in the soil appeared to be confined to discrete soil particles rather than being distributed equally on the soil particles, suggesting the source of the radioactivity was remnant ore particles.

  13. Elevated naturally occurring arsenic in a semiarid oxidizing system, Southern High Plains aquifer, Texas, USA

    USGS Publications Warehouse

    Scanlon, B.R.; Nicot, J.-P.; Reedy, R.C.; Kurtzman, D.; Mukherjee, A.; Nordstrom, D.K.

    2009-01-01

    High groundwater As concentrations in oxidizing systems are generally associated with As adsorption onto hydrous metal (Al, Fe or Mn) oxides and mobilization with increased pH. The objective of this study was to evaluate the distribution, sources and mobilization mechanisms of As in the Southern High Plains (SHP) aquifer, Texas, relative to those in other semiarid, oxidizing systems. Elevated groundwater As levels are widespread in the southern part of the SHP (SHP-S) aquifer, with 47% of wells exceeding the current EPA maximum contaminant level (MCL) of 10 ??g/L (range 0.3-164 ??g/L), whereas As levels are much lower in the north (SHP-N: 9% ??? As MCL of 10 ??g/L; range 0.2-43 ??g/L). The sharp contrast in As levels between the north and south coincides with a change in total dissolved solids (TDS) from 395 mg/L (median north) to 885 mg/L (median south). Arsenic is present as arsenate (As V) in this oxidizing system and is correlated with groundwater TDS (Spearman's ?? = 0.57). The most likely current source of As is sorbed As onto hydrous metal oxides based on correlations between As and other oxyanion-forming elements (V, ?? = 0.88; Se, ?? = 0.54; B, ?? = 0.51 and Mo, ?? = 0.46). This source is similar to that in other oxidizing systems and constitutes a secondary source; the most likely primary source being volcanic ashes in the SHP aquifer or original source rocks in the Rockies, based on co-occurrence of As and F (?? = 0.56), oxyanion-forming elements and SiO2 (?? = 0.41), which are found in volcanic ashes. High groundwater As concentrations in some semiarid oxidizing systems are related to high evaporation. Although correlation of As with TDS in the SHP aquifer may suggest evaporative concentration, unenriched stable isotopes (??2H: -65 to -27; ??18O: -9.1 to -4.2) in the SHP aquifer do not support evaporation. High TDS in the SHP aquifer is most likely related to upward movement of saline water from the underlying Triassic Dockum aquifer. Mobilization of As in other semiarid oxidizing systems is caused by increased pH; however, pH in the SHP aquifer is near neutral (10-90 percentiles, 7.0-7.6). Although many processes, such as competitive desorption with SiO2, VO4, or PO4, could be responsible for local mobilization of As in the SHP aquifer, the most plausible explanation for the regional As distribution and correlation with TDS is the counterion effect caused by a change from Ca- to Na-rich, water as shown by the high correlation between As and Na/(Ca)0.5 ratios (?? = 0.57). This change in chemistry is related to mixing with saline water that moves upward from the underlying Dockum aquifer. This counterion effect may mobilize other anions and oxyanion-forming elements that are correlated with As (F, V, Se, B, Mo and SiO2). Competition among the oxyanions for sorption sites may enhance As mobilization. The SHP case study has similar As sources to those of other semiarid, oxidizing systems (original volcanic ash source followed by sorption onto hydrous metal oxides) but contrasts with these systems by showing lack of evaporative concentration and pH mobilization of As but counterion mobilization of As instead in the SHP-S aquifer. ?? 2009 Elsevier Ltd.

  14. 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

  15. ELASTOGRAPHIC EVALUATION OF NATURALLY OCCURING TENDON AND LIGAMENT INJURIES OF THE EQUINE DISTAL LIMB.

    PubMed

    Lustgarten, Meghann; Redding, W Rich; Labens, Raphael; Davis, Weston; Daniel, Thomas M; Griffith, Emily; Seiler, Gabriela S

    2015-01-01

    Compression elastography is an ultrasonographic technique that estimates tissue strain and may have utility in diagnosing and monitoring soft tissue injuries in the equine athlete. Recently, elastography has been proven to be a feasible and repeatable imaging modality for evaluating normal tendons and ligaments of the equine distal forelimb. The purposes of this prospective study were to investigate the ability of elastography to detect spontaneously occurring lesions of equine tendons and ligaments diagnosed with magnetic resonance imaging (MRI) and gray-scale ultrasound (US) and to characterize the differences in the elastographic appearance of acute vs. chronic injuries. Fifty seven horses with a total of 65 lesions were evaluated. Images were assessed quantitatively and qualitatively. Acute lesions were found to be significantly softer (P < 0.0001) than chronic lesions (P < 0.0001) and the stiffness of lesions increased with progression of healing (P = 0.0138). A negative correlation between lesion hypoechogenicity and softness was appreciated with more hypoechoic lesions appearing softer (P = 0.0087) and more hyperechoic regions harder (P = 0.0002). A similar finding occurred with increased signal intensity on short tau inversion recovery (STIR) and proton density (PD) MRI sequences correlating with increased softness on elastography (P = 0.0164). Using US and MRI as references, commonly encountered soft tissue injuries of the equine distal limb could be detected with elastography. However, elastography was limited for detecting small, proximal injuries of the hindlimb proximal suspensory ligament. Elastographic evaluation of equine tendons and ligaments may allow better characterization of lesion chronicity and severity, and sequential examinations may optimize lesion management, rehabilitation, and return to training. PMID:26304065

  16. 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

  17. 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

  18. 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 γ-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.

  19. Identification and clinical relevance of naturally occurring human CD8+HLA-DR+ regulatory T cells.

    PubMed

    Arruvito, Lourdes; Payaslián, Florencia; Baz, Plácida; Podhorzer, Ariel; Billordo, Ariel; Pandolfi, Julieta; Semeniuk, Guillermo; Arribalzaga, Eduardo; Fainboim, Leonardo

    2014-11-01

    The lack of responsiveness to self and non-self Ags is normally maintained by multiple mechanisms, including the suppressive activities of several T cell subsets. In this study, we show that CD8(+) T cells from both adult peripheral blood and umbilical cord blood mononuclear cells constitutively expressing HLA-DR represent a natural human CD8(+) regulatory T cell subset. Their suppressive effect appears to be cell-to-cell contact dependent and may involve CTLA-4 signaling between neighboring T cells. These regulatory T cells can be expanded in vitro and exhibit a suppressive capacity similar to that observed in ex vivo CD8(+)HLA-DR(+) T cells. The high frequency of CD8(+)HLA-DR(+) T cells that we detected in patients with non-small cell lung cancer deserves further work to confirm their putative suppressor effect within the tumor. PMID:25261474

  20. Efficacy of two iodine teat dips based on reduction of naturally occurring new intramammary infections.

    PubMed

    Foret, C J; Corbellini, C; Young, S; Janowicz, P

    2005-01-01

    The efficacy of 2 teat dips, product 1 (Della Care with 5 to 8 ppm of free iodine, used as a positive control) and product 2 (New Della Care with 12 to 16 ppm of free iodine), was compared using a natural exposure trial on dairy cattle. The trial was based on National Mastitis Council guidelines and performed over 9 mo. Both teat dips contained 0.25% iodine. Product 2 reduced the infection rate 57.6% for major pathogens and 53.7% for minor pathogens, compared with the positive control. Product 2 gave highly significant reductions for Staphylococcus aureus, coagulase-negative staphylococci, and Corynebacterium bovis. Teat skin, teat ends, and teat hyperkeratosis were evaluated during trial. No significant difference in teat condition was observed between these 2 products. PMID:15591409

  1. 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: ≤ 30 m) and deep (> 30 m) wells were analysed from two unconnected high-fluoride endemic areas. At the Chiang Mai site, 31% of the shallow wells contained hazardous levels (≥ 1.5 mg/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

  2. 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 Nef’s 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

  3. 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...

  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. 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…

  6. CHARACTERIZATION OF VARIOUS ISOLATES OF A NATURALLY OCCURRING RECOMBINANT AVIAN LEUKOSIS VIRUS USING BIOLOGICAL ASSAYS AND POLYMERASE CHAIN REACTION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recently, we have isolated a naturally occurring recombinant avian leukosis virus (ALV) containing the envelope of ALV-B and LTR of ALV-J from commercial layer flocks affected with myeloid leukosis. Seven new isolates of the recombinant ALV, isolated from the same flock, were characterized using bio...

  7. 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…

  8. 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…

  9. 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…

  10. 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 ...

  11. 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

  12. Pig Reticulocytes. III. Glucose permeability in naturally occurring reticulocytes and red cells from newborn piglets

    PubMed Central

    Kim, HD; Luthra, MG

    1977-01-01

    The loss of facilitated glucose transport of red cells occurring in the newborn pig was monitored in 11 density-separated cells from birth to a 4 wk of age. At birth there was a threefold increase in glucose permeability from the lightest cells to the most dense, suggesting that cells having progressively less glucose permeability are released into the circulation as gestation proceeds. Because of extraordinary stimulation of erythropoietic activity, the uppermost top fraction constituting 2-3 percent of the total cells is composed purely of reticulocytes in the growing animal. The glucose permeability of these reticulocytes which at birth has a slow but significant rate of 3.7 μmol/ml cell x min at 25 degrees C is rapidly decreased within 3-4 days to the level of reticulocytes produced in the adult in response to phenylhydrazine assault. Moreover, reticulocytes themselves discard their membrane permeability to glucose in the course of maturation to red cells. Thus, even though reticulocytes at birth are permeable to glucose, they will become red cells practically impervious to glucose within a few days. These findings suggest that the transition from a glucose- permeable fetal state to a glucose-impermeable postnatal state is brought about by two mechanisms: (a) dilution of fetal cells by glucose-impervious cells produced coincidentally with or shortly after birth; and (b) elimination of fetal cells, which have a shorter half-life, from the circulation. PMID:894256

  13. 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.

  14. Mobilization and transport of naturally occurring enterococci in beach sands subject to transient infiltration of seawater.

    PubMed

    Russell, Todd L; Yamahara, Kevan M; Boehm, Alexandria B

    2012-06-01

    This study explores the transport of enterococci (ENT) from naturally contaminated beach sands to the groundwater table via infiltrating seawater using field, laboratory, and modeling experiments. ENT were readily mobilized and transported through the unsaturated zone during infiltration events in both the field and laboratory column experiments. Detachment mechanisms were investigated using a modified version of HYDRUS-1D. Three models for detachment kinetics were tested. Detachment kinetics that are first order with respect to the rate of change in the water content and attached surface bacterial concentrations were found to provide a best fit between predicted and observed data. From these experimental and model results we conclude that detachment mechanisms associated with the rapid increases in pore water content such as air-water interface scouring and thin film expansion are likely drivers of ENT mobilization in the investigated system. These findings suggest that through-beach transport of ENT may be an important pathway through which ENT from beach sands are transported to beach groundwater where they may be discharged to coastal waters via submarine groundwater discharge. PMID:22533299

  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 Enzyme Activity Variation in DROSOPHILA MELANOGASTER. I. Sources of Variation for 23 Enzymes

    PubMed Central

    Laurie-Ahlberg, C. C.; Wilton, A. N.; Curtsinger, J. W.; Emigh, T. H.

    1982-01-01

    The genetic component of variation of enzyme activity levels in Drosophila melanogaster was investigated by using 48 second- and 48 third-chromosome isogenic substitution lines derived from natural populations. The results confirm those of our earlier experiments with the same lines and extend them to a number of additional enzymes. All 23 enzymes show a significant genetic component to the variation in one or both sets of lines and only a small part of this variation is accounted for by variation among the lines in the amount of tissue per fly. The magnitude of line effects is, in most cases, considerably larger than the magnitude of environmental and measurement error effects, and the line effects are approximately continuous in distribution. Variation in the geographic origin and karyotype of the chromosomes generally does not contribute to the line component of variation, but allozymes provide an important source of variation for a few of the enzymes. Many of the enzymes show evidence for variation of activity modifiers that are not linked to the structural locus of the enzyme. PMID:6818102

  18. The origin of naturally occurring perchlorate: the role of atmospheric processes.

    PubMed

    Dasgupta, Purnendu K; Martinelango, P Kalyani; Jackson, W Andrew; Anderson, Todd A; Tian, Kang; Tock, Richard W; Rajagopalan, Srinath

    2005-03-15

    Perchlorate, an iodide uptake inhibitor, is increasingly being detected in new places and new matrices. Perchlorate contamination has been attributed largelyto the manufacture and use of ammonium perchlorate (the oxidizer in solid fuel rockets) and/or the earlier use of Chilean nitrate as fertilizer (approximately 0.1% perchlorate). However, there are regions such as the southern high plains (Texas Panhandle) where there is no clear historical or current evidence of the extensive presence of rocket fuel or Chilean fertilizer sources. The occurrence of easily measurable concentrations of perchlorate in such places is difficult to understand. In the southern high plains groundwater, perchlorate is better correlated with iodate, known to be of atmospheric origin, compared to any other species. We show that perchlorate is readily formed by a variety of simulated atmospheric processes. For example, it is formed from chloride aerosol by electrical discharge and by exposing aqueous chloride to high concentrations of ozone. We report that perchlorate is present in many rain and snow samples. This strongly suggests that some perchlorate is formed in the atmosphere and a natural perchlorate background of atmospheric origin should exist. PMID:15819211

  19. 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

  20. 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

  1. Naturally Occurring Carbazole Alkaloids from Murraya koenigii as Potential Antidiabetic Agents.

    PubMed

    Patel, Om P S; Mishra, Akansha; Maurya, Ranjani; Saini, Deepika; Pandey, Jyotsana; Taneja, Isha; Raju, Kanumuri S R; Kanojiya, Sanjeev; Shukla, Sanjeev K; Srivastava, Mahendra N; Wahajuddin, M; Tamrakar, Akhilesh K; Srivastava, Arvind K; Yadav, Prem P

    2016-05-27

    This study identified koenidine (4) as a metabolically stable antidiabetic compound, when evaluated in a rodent type 2 model (leptin receptor-deficient db/db mice), and showed a considerable reduction in the postprandial blood glucose profile with an improvement in insulin sensitivity. Biological studies were directed from the preliminary in vitro evaluation of the effects of isolated carbazole alkaloids (1-6) on glucose uptake and GLUT4 translocation in L6-GLUT4myc myotubes, followed by an investigation of their activity (2-5) in streptozotocin-induced diabetic rats. The effect of koenidine (4) on GLUT4 translocation was mediated by the AKT-dependent signaling pathway in L6-GLUT4myc myotubes. Moreover, in vivo pharmacokinetic studies of compounds 2 and 4 clearly showed that compound 4 was 2.7 times more bioavailable than compound 2, resulting in a superior in vivo efficacy. Therefore, these studies suggested that koenidine (4) may serve as a promising lead natural scaffold for managing insulin resistance and diabetes. PMID:27136692

  2. 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

  3. 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

  4. 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

  5. Using Naturally Occurring Radionuclides To Determine Drinking Water Age in a Community Water System.

    PubMed

    Waples, James T; Bordewyk, Jason K; Knesting, Kristina M; Orlandini, Kent A

    2015-08-18

    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 (90)Y/(90)Sr and (234)Th/(238)U in discrete drinking water samples of known age accurately estimated water age up to 9 days old (σest: ± 3.8 h, P < 0.0001, r(2) = 0.998, n = 11) and 25 days old (σest: ± 13.3 h, P < 0.0001, r(2) = 0.996, n = 12), respectively. Moreover, (90)Y-derived water ages in a community water system (6.8 × 10(4) m(3) 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. PMID:26200208

  6. 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

  7. Genetic background and GxE interactions modulate the penetrance of a naturally occurring wing mutation in Drosophila melanogaster.

    PubMed

    Lachance, Joseph; Jung, Lawrence; True, John R

    2013-11-01

    Many genes involved in producing complex traits are incompletely penetrant. One such example is vesiculated, an X-linked gene in Drosophila melanogaster that results in wing defects. To examine the genetic architecture of a complex trait (wings containing vesicles), we placed a naturally occurring variant into multiple autosomal backgrounds and quantified penetrance and expressivity at a range of developmental temperatures. We found significant epistasis, genotype-by-environment interactions, and maternal effects. Sex and temperature effects were modulated by genetic background. The severity of wing phenotypes also varied across different genetic backgrounds, and expressivity was positively correlated with penetrance. We also found evidence of naturally segregating suppressors of vesiculated. These suppressors were present on both the second and third chromosomes, and complex interactions were observed. Taken together, these findings indicate that multiple genetic and environmental factors modulate the phenotypic effects of a naturally occurring vesiculated allele. PMID:24002866

  8. 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.

  9. 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.

  10. Collection, Isolation and Enrichment of Naturally Occurring Magnetotactic Bacteria from the Environment

    PubMed Central

    Oestreicher, Zachery; Lower, Steven K.; Lin, Wei; Lower, Brian H.

    2012-01-01

    Magnetotactic bacteria (MTB) are aquatic microorganisms that were first notably described in 19751 from sediment samples collected in salt marshes of Massachusetts (USA). Since then MTB have been discovered in stratified water- and sediment-columns from all over the world2. One feature common to all MTB is that they contain magnetosomes, which are intracellular, membrane-bound magnetic nanocrystals of magnetite (Fe3O4) and/or greigite (Fe3S4) or both3, 4. In the Northern hemisphere, MTB are typically attracted to the south end of a bar magnet, while in the Southern hemisphere they are usually attracted to the north end of a magnet3,5. This property can be exploited when trying to isolate MTB from environmental samples. One of the most common ways to enrich MTB is to use a clear plastic container to collect sediment and water from a natural source, such as a freshwater pond. In the Northern hemisphere, the south end of a bar magnet is placed against the outside of the container just above the sediment at the sediment-water interface. After some time, the bacteria can be removed from the inside of the container near the magnet with a pipette and then enriched further by using a capillary racetrack6 and a magnet. Once enriched, the bacteria can be placed on a microscope slide using a hanging drop method and observed in a light microscope or deposited onto a copper grid and observed using transmission electron microscopy (TEM). Using this method, isolated MTB may be studied microscopically to determine characteristics such as swimming behavior, type and number of flagella, cell morphology of the cells, shape of the magnetic crystals, number of magnetosomes, number of magnetosome chains in each cell, composition of the nanomineral crystals, and presence of intracellular vacuoles. PMID:23183960

  11. 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.

  12. 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.

  13. 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

  14. Overexpression of programmed death ligands in naturally occurring postweaning multisystemic wasting syndrome.

    PubMed

    Yue, Feng; Cheng, Anchun; Zhu, Yanping; Li, Peng; Zhang, Yanfang; Sun, Guopeng; Wang, Mingshu; Wang, Xuannian

    2015-03-01

    Postweaning multisystemic wasting syndrome (PMWS) is regarded as an immunosuppressive disease in pigs caused by porcine circovirus type 2 (PCV2). Immune inhibitory receptors, particularly programmed death 1/programmed death-ligands (PD-1/PD-Ls) are presumably involved in the immunopathogenesis of PMWS. The aim of this investigation was to examine the relationship of immune inhibitory receptors and immunocompromised by PMWS. Nine 45-day-old conventional pigs were selected from a farm where pigs exhibited typical signs of PMWS (wasting and respiratory disorders) and tested positive for PCV2 infection by polymerase chain reaction (PCR). Six pigs were selected as controls due to their notably healthy state and absence of PCV2 infection. Heparinized blood samples were taken from each pig for pathogen detection and isolation of peripheral blood mononuclear cells (PBMCs), from which mRNA expression of immunomodulatory molecule (PD-1, PD-L1, PD-L2, PTEN, CTLA-4, LAG-3, and Foxp3) and cytokines (IL-10, IL-2, and IFN-γ) was determined. Proliferation of PBMCs was also assessed by flow cytometry utilizing cellular labeling dilutions for detection. The mRNA levels of PD-L1 (p<0.01), PD-L2 (p<0.05), and PTEN (p<0.01) were remarkably increased in the PBMCs of diseased pigs compared to healthy pigs, whereas no change was observed for PD-1, CTLA-4, LAG-3, and Foxp3 expression. Cytokine IL-10 mRNA levels were significantly elevated (p<0.01), while IL-2 and IFN-γ mRNA levels tended to be only slightly increased in the PBMCs of affected pigs compared to healthy controls. The proliferation of PBMCs was also decreased in diseased pigs. These data suggest that overexpression of PD-L1 and PD-L2 mRNA is one mechanism by which immunosupression of PMWS pigs occurs, supporting a new therapeutic strategy focused on PD-Ls for pigs suffering from PMWS. PMID:25594677

  15. 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

  16. 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

  17. 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.

  18. 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.

  19. 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.

  20. Naturally occurring bacteriophages lyse a large proportion of canine and feline uropathogenic Escherichia coli isolates in vitro.

    PubMed

    Freitag, T; Squires, R A; Schmid, J

    2008-08-01

    We investigated the feasibility of bacteriophage therapy to combat canine and feline Escherichia coli urinary tract infections (UTIs) by testing the in vitro lytic ability of 40 naturally occurring bacteriophages on 53 uropathogenic E. coli (UPEC). The mean number of UPEC strains lysed by an individual bacteriophage was 21/53 (40%, range 17-72%). In total, 50/53 (94%) of the UPEC strains were killed by one or more of the bacteriophages. Ten bacteriophages lysed 51% of UPEC strains individually and 92% of UPEC strains as a group. Electron microscopy and DNA sequencing of 5 'promising' bacteriophages revealed that 4 bacteriophages belonged to the lytic T4-like genus, while one displayed morphologic similarity to temperate P2-like bacteriophages. Overall, these results indicate that the majority of UPEC are susceptible to lysis by naturally occurring bacteriophages. Thus, bacteriophages show promise as therapeutic agents for treatment of canine and feline E. coli UTIs. PMID:17959211

  1. Cellular targets and mechanistic strategies of remyelination-promoting IgMs as part of the naturally occurring autoantibody repertoire

    PubMed Central

    Watzlawik, Jens O; Wootla, Bharath; Painter, Meghan M; Warrington, Arthur E; Rodriguez, Moses

    2014-01-01

    Immunoglobulins with germline sequences occur in invertebrates and vertebrates and are named naturally occurring autoantibodies (NAbs). NAbs may target foreign antigens, self- or altered self-components and are part of the normal immunoglobulin repertoire. Accumulating evidence indicates that naturally occurring antibodies can act as systemic surveillance molecules, which tag, damaged or stressed cells, invading pathogens and toxic cellular debris for elimination by the immune system. In addition to acting as detecting molecules, certain types of NAbs actively signal in different cell types with a broad range of responses from induction of apoptosis in cancer cells to stimulation of remyelination in glial cells. This review emphasizes functions and characteristics of NAbs with focus on remyelination-promoting mouse and human antibodies. Human remyelination-promoting NAbs are potential therapeutics to combat a wide spectrum of disease processes including demyelinating diseases like multiple sclerosis. We will highlight the identified glycosphingolipid (SL) antigens of polyreactive remyelination-promoting antibodies and their proposed mechanism(s) of action. The nature of the identified antigens suggests a lipid raft-based mechanism for remyelination-promoting antibodies with SLs as most essential raft components. However, accumulating evidence also suggests involvement of other antigens in stimulation of remyelination, which will be discussed in the text. PMID:24053345

  2. Laccase-catalysed oxidations of naturally occurring phenols: from in vivo biosynthetic pathways to green synthetic applications.

    PubMed

    Jeon, Jong-Rok; Baldrian, Petr; Murugesan, Kumarasamy; Chang, Yoon-Seok

    2012-05-01

    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

  3. Revealing the structural nature of the Cd isotopes

    NASA Astrophysics Data System (ADS)

    Garrett, P. E.; Diaz Varela, A.; Green, K. L.; Jamieson, D. S.; Jigmeddorj, B.; Wood, J. L.; Yates, S. W.

    2015-10-01

    The even-even Cd isotopes have provided fertile ground for the investigation of collectivity in nuclei. Soon after the development of the Bohr model, the stable Cd isotopes were identified as nearly harmonic vibrators based on their excitation energy patterns. The measurements of enhanced B (E 2) values appeared to support this interpretation. Shape co-existing rotational-like intruder bands were discovered, and mixing between the configurations was invoked to explain the deviation of the decay pattern of multiphonon vibrational states. Very recently, a detailed analysis of the low-lying levels of 110Cd combining results of the (n ,n' γ) reaction and high-statistics β decay, provided strong evidence that the mixing between configurations is weak, except for the ground-state band and ``Kπ =0+ '' intruder band. The analysis of the levels in 110Cd has now been extended to 3 MeV, and combined with data for 112Cd and previous Coulomb excitation data for 114Cd, enables a detailed map of the E 2 collectivity in these nuclei, demanding a complete re-interpretation of the structure of the stable Cd isotopes.

  4. 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.

  5. 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.

  6. A Naturally Occurring Single Amino Acid Replacement in Multiple Gene Regulator of Group A Streptococcus Significantly Increases Virulence

    PubMed Central

    Sanson, Misu; O'Neill, Brian E.; Kachroo, Priyanka; Anderson, Jeff R.; Flores, Anthony R.; Valson, Chandni; Cantu, Concepcion C.; Makthal, Nishanth; Karmonik, Christof; Fittipaldi, Nahuel; Kumaraswami, Muthiah; Musser, James M.; Olsen, Randall J.

    2016-01-01

    Single-nucleotide polymorphisms (SNPs) are the most common source of genetic variation within a species; however, few investigations demonstrate how naturally occurring SNPs may increase strain virulence. We recently used group A Streptococcus as a model pathogen to study bacteria strain genotype–patient disease phenotype relationships. Whole-genome sequencing of approximately 800 serotype M59 group A Streptococcus strains, recovered during an outbreak of severe invasive infections across North America, identified a disproportionate number of SNPs in the gene encoding multiple gene regulator of group A Streptococcus (mga). Herein, we report results of studies designed to test the hypothesis that the most commonly occurring SNP, encoding a replacement of arginine for histidine at codon 201 of Mga (H201R), significantly increases virulence. Whole transcriptome analysis revealed that the H201R replacement significantly increased expression of mga and 54 other genes, including many proven virulence factors. Compared to the wild-type strain, a H201R isogenic mutant strain caused significantly larger skin lesions in mice. Serial quantitative bacterial culture and noninvasive magnetic resonance imaging also demonstrated that the isogenic H201R strain was significantly more virulent in a nonhuman primate model of joint infection. These findings show that the H201R replacement in Mga increases the virulence of M59 group A Streptococcus and provide new insight to how a naturally occurring SNP in bacteria contributes to human disease phenotypes. PMID:25476528

  7. 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.

  8. 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.

  9. 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

  10. 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.

  11. 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...

  12. Computed Tomography Imaging of Solid Tumors Using a Liposomal-Iodine Contrast Agent in Companion Dogs with Naturally Occurring Cancer

    PubMed Central

    Ghaghada, Ketan B.; Sato, Amy F.; Starosolski, Zbigniew A.; Berg, John; Vail, David M.

    2016-01-01

    Objectives Companion dogs with naturally occurring cancer serve as an important large animal model in translational research because they share strong similarities with human cancers. In this study, we investigated a long circulating liposomal-iodine contrast agent (Liposomal-I) for computed tomography (CT) imaging of solid tumors in companion dogs with naturally occurring cancer. Materials and Methods The institutional animal ethics committees approved the study and written informed consent was obtained from all owners. Thirteen dogs (mean age 10.1 years) with a variety of masses including primary and metastatic liver tumors, sarcomas, mammary carcinoma and lung tumors, were enrolled in the study. CT imaging was performed pre-contrast and at 15 minutes and 24 hours after intravenous administration of Liposomal-I (275 mg/kg iodine dose). Conventional contrast-enhanced CT imaging was performed in a subset of dogs, 90 minutes prior to administration of Liposomal-I. Histologic or cytologic diagnosis was obtained for each dog prior to admission into the study. Results Liposomal-I resulted in significant (p < 0.05) enhancement and uniform opacification of the vascular compartment. Non-renal, reticulo-endothelial systemic clearance of the contrast agent was demonstrated. Liposomal-I enabled visualization of primary and metastatic liver tumors. Sub-cm sized liver lesions grossly appeared as hypo-enhanced compared to the surrounding normal parenchyma with improved lesion conspicuity in the post-24 hour scan. Large liver tumors (> 1 cm) demonstrated a heterogeneous pattern of intra-tumoral signal with visibly higher signal enhancement at the post-24 hour time point. Extra-hepatic, extra-splenic tumors, including histiocytic sarcoma, anaplastic sarcoma, mammary carcinoma and lung tumors, were visualized with a heterogeneous enhancement pattern in the post-24 hour scan. Conclusions The long circulating liposomal-iodine contrast agent enabled prolonged visualization of small and large tumors in companion dogs with naturally occurring cancer. The study warrants future work to assess the sensitivity and specificity of the Liposomal-I agent in various types of naturally occurring canine tumors. PMID:27031614

  13. 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.

  14. 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.

  15. 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

  16. 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.

  17. 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

  18. 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

  19. Distribution of injected technetium(99m)-labeled mesenchymal stem cells in horses with naturally occurring tendinopathy.

    PubMed

    Becerra, Patricia; Valdés Vázquez, Miguel A; Dudhia, Jayesh; Fiske-Jackson, Andrew R; Neves, Francisco; Hartman, Neil G; Smith, Roger K W

    2013-07-01

    This study aimed to investigate immediate cell survival and distribution following different administration routes of mesenchymal stem cells (MSCs) into naturally occurring tendon injuries. Ten million MSCs, labeled with technetium-99m hexamethylpropyleneamine oxime, were implanted into 13 horses with naturally occurring tendon or ligament injuries intra-lesionally, intravenously and by regional perfusion, and traced for up to 48 h using planar gamma scintigraphy. Labeling efficiencies varied between 1.8% and 18.5% (mean 9.3%). Cells were retained in the damaged area after intra-lesional administration but only 24% of cells were still present within the tendon after 24 h. After intravenous injection, cells largely distributed to the lung fields, with no detectable cells in the tendon lesions. Significant labeling of the tendon lesions was observed in 11/12 horses following regional perfusion but at a lower level to intra-lesional injection. The highest cell numbers were retained after intra-lesional injection, although with considerable cell loss, while regional perfusion may be a viable alternative for MSC delivery. Cells did not "home" to damaged tendon in large numbers after intravenous administration. Cells were detected in the lungs most frequently after intravascular administration, although with no adverse effects. Low cell retention has important implications for designing effective clinical therapies for human clinical use. PMID:23508674

  20. 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.

  1. 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

  2. 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

  3. Ba isotopic signature for early differentiation between Cs and Ba in natural fission reactors

    NASA Astrophysics Data System (ADS)

    Hidaka, Hiroshi; Gauthier-Lafaye, François

    2008-08-01

    Ba isotopic studies of the Oklo and Bangombé natural fission reactors in east Gabon provide information on the geochemical behavior of radioactive Cs ( 135Cs and 137Cs) in a geological medium. Large isotopic deviations derived from fissiogenic Ba were found in chemical leachates of the reactor uraninites. The fissiogenic Ba isotopic patterns calculated by subtracting the non-fissiogenic component are classified into three types that show different magnifications of chemical fractionation between Cs and Ba. In addition, the isotopic signatures of fissiogenic 135Ba, 137Ba and 138Ba suggest an early differentiation between Cs and Ba of less than 20 years after the production of fissiogenic Cs and Ba. On the other hand, only small excesses of 135Ba ( ɛ < +1.8) and/or 137Ba ( ɛ < +1.3) were identified in some clay samples, which might have resulted from selective adsorption of 135Cs and 137Cs that migrated from the reactors by differentiation.

  4. 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).

  5. An Isotope Fractionation - Reactive Transport Model to Assess Natural Attenuation of Chlorinated Solvents

    NASA Astrophysics Data System (ADS)

    Stack, P.; Kuder, T.; Vanderford, M.; Philp, P.; van Breukelen, B.

    2012-04-01

    While compound-specific isotope analysis has been used successfully to demonstrate in situ degradation of chlorinated solvents, it suffers from uncertainty resulting from geological heterogeneity and variability in redox conditions. The primary objective of this project was to create an Isotope Fractionation - Reactive Transport Model (IF-RTM) capable of simultaneously simulating multiple isotopes within a complex reaction network, in this case C, Cl and H isotopes during the sequential degradation of chlorinated ethenes, and with heterogeneous environmental conditions. This IF-RTM can then be used as a tool to quantitatively assess contaminant mass destruction through natural attenuation processes, potentially reducing the required monitoring effort, informing remediation or mitigation efforts, and providing insight into the relative impacts of mass attenuation mechanisms. A greater level of model confidence can be obtained by incorporating isotope fractionation into the model output, rather than the usual concentration only approach. A model code capable of simulating concentration changes and isotope fractionation of multiple isotopes (C, Cl, H) during reductive dechlorination and aerobic degradation has been developed using the biogeochemical speciation and transport modelling programme PHREEQC-2. This model is novel not only because it simulates multiple isotopes, but also because it also incorporates secondary isotope effects in the simulation of chlorine isotope fractionation. Microcosm data, including a dataset representing the first a comprehensive, three-isotope (C, Cl, H) characterisation of the TCE reductive dechlorination sequence will be presented and have been used to calibrate/validate this model. The model was found to be capable of simulating the carbon, chlorine and hydrogen isotope fractionation patterns and change in concentration for TCE and its degradation products throughout the reductive dechlorination process. In the next stage of this project solute transport capability will be added to the model by modifying it to be used with a reactive multi-component transport model such as PHAST. The final IF-RTM product will have the capability of simulating changes in concentrations of the parent compound (e.g. PCE) and its degradation products (e.g. VC) and the isotope ratios (of C, Cl and H) of each compound in 3D space. This IF-RTM can also be modified to include fractionation resulting from physical processes such as hydrodynamic dispersion. The developed model will be tested on a large dataset collected at a contaminated field site, namely the TCE plume at Hill AFB, UT.

  6. 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

  7. 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...

  8. 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...

  9. 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

  10. 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

  11. 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

  12. 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 (n=2) and Lactococcus lactis ssp. lactis (n=18). Nisin genes were identified by polymerase chain reaction in 7 of these cultures. The identified bacteriocinogenic and bacteriocinogenic-like cultures were highly variable concerning the production and activity of antimicrobial substances, even when they were genetically similar. The obtained results indicated the need for molecular and phenotypic methodologies to properly characterize bacteriocinogenic LAB, as well as the potential use of these cultures as tools to provide food safety. PMID:20630205

  13. Iron isotopes in the Seine River (France): Natural versus anthropogenic sources

    NASA Astrophysics Data System (ADS)

    Chen, Jiu-Bin; Busigny, Vincent; Gaillardet, Jérôme; 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 (δ56Fe 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 δ56Fe and δ66Zn 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 δ56Fe 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 δ56Fe 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.

  14. Total synthesis of isotopically enriched Si-29 silica NPs as potential spikes for isotope dilution quantification of natural silica NPs.

    PubMed

    Pálmai, Marcell; Szalay, Roland; Bartczak, Dorota; Varga, Zoltán; Nagy, Lívia Naszályi; 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

  15. 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 0.2 mL of aqueous solutions with acetone concentrations of 0.3-121 mg/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 3 days including a fasting period of 24 h. 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

  16. Results of the European Commission Marina II study: part II--effects of discharges of naturally occurring radioactive material.

    PubMed

    Betti, M; Aldave de las Heras, L; Janssens, A; Henrich, E; Hunter, G; Gerchikov, M; Dutton, M; van Weers, A W; Nielsen, S; Simmonds, J; Bexon, A; Sazykina, T

    2004-01-01

    Enhanced levels of naturally occurring radioactive materials (NORM) are produced through various industrial operations and may lead to discharges to the marine environment. A recent study, called MARINA II, carried out for the European Commission considered discharges of radionuclides from the NORM industries to north European marine waters and their consequences. There are two main sources that were considered in the study. The use of phosphogypsum during the production of phosphoric acid by the fertiliser industry and the pumping of oil and gas from the continental shelf in the North Sea which produces large quantities of water contaminated with enhanced levels of naturally occurring radionuclides. Discharges of alpha emitting radionuclides from these two industries have contributed significantly to the total input of alpha emitters to north European waters over the period 1981-2000 (data were not available prior to 1981). Discharges due to the use of phosphogypsum have declined since the early 1990s and are now very low. Discharges from the oil and gas industries stabilised in the second half of the 1990s and are now the major contributor to alpha discharges to the region. As most European countries do not report discharges of radioactivity with the water produced during extraction, there is considerable uncertainty in the discharges used in the study. The impact of the discharges has been estimated both in terms of the effect on non-human biota and the radiological impact for people. In the 1980s the radiation dose rates to marine biota in the region around a phosphate plant on the north-west coast of England were as high due to the discharges from the phosphate plant as those near to the Sellafield reprocessing plant due to its discharges. In recent years the additional dose to marine biota in this region due to the past NORM discharges is of the same order of magnitude as the natural background. The collective dose rate was estimated to determine the radiological impact on people. The peak collective dose rate from the NORM industries occurred in 1984 and was just over 600 manSv y(-1). The collective dose rate fell with time as discharges from the phosphate industry reduced and was estimated as under 200 manSv y(-1) in 2000. PMID:15063553

  17. Use of Sulphur and Boron Isotopes to Identify Natural Gas Processing Emissions Sources

    NASA Astrophysics Data System (ADS)

    Bradley, C. E.; Norman, A.; Wieser, M. E.

    2003-12-01

    Natural gas processing results in the emission of large amounts of gaseous pollutants as a result of planned and / or emergency flaring, sulphur incineration, and in the course of normal operation. Since many gas plants often contribute to the same air shed, it is not possible to conclusively determine the sources, amounts, and characteristics of pollution from a particular processing facility using traditional methods. However, sulphur isotopes have proven useful in the apportionment of sources of atmospheric sulphate (Norman et al., 1999), and boron isotopes have been shown to be of use in tracing coal contamination through groundwater (Davidson and Bassett, 1993). In this study, both sulphur and boron isotopes have been measured at source, receptor, and control sites, and, if emissions prove to be sufficiently distinct isotopically, they will be used to identify and apportion emissions downwind. Sulphur is present in natural gas as hydrogen sulphide (H2S), which is combusted to sulphur dioxide (SO2) prior to its release to the atmosphere, while boron is present both in hydrocarbon deposits as well as in any water used in the process. Little is known about the isotopic abundance variations of boron in hydrocarbon reservoirs, but Krouse (1991) has shown that the sulphur isotope composition of H2S in reservoirs varies according to both the concentration and the method of formation of H2S. As a result, gas plants processing gas from different reservoirs are expected to produce emissions with unique isotopic compositions. Samples were collected using a high-volume air sampler placed directly downwind of several gas plants, as well as at a receptor site and a control site. Aerosol sulphate and boron were collected on quartz fibre filters, while SO2 was collected on potassium hydroxide-impregnated cellulose filters. Solid sulphur samples were taken from those plants that process sulphur in order to compare the isotopic composition with atmospheric measurements. A method was developed to extract and concentrate boron for isotope analysis. Isotopic composition and concentrations of both sulphur and boron were measured in order to determine whether emissions have distinct sulphur and/or boron isotopic compositions. Preliminary results of SO2 and solid sulphur analysis show values that range from +3 to +30 \\permil.

  18. Radiological Impact Associated to Technologically Enhanced Naturally Occurring Radioactive Materials (TENORM) from Coal-Fired Power Plants Emissions - 13436

    SciTech Connect

    Dinis, Maria de Lurdes; Fiuza, Antonio; Soeiro de Carvalho, Jose; Gois, Joaquim; Meira Castro, Ana Cristina

    2013-07-01

    Certain materials used and produced in a wide range of non-nuclear industries contain enhanced activity concentrations of natural radionuclides. In particular, electricity production from coal is one of the major sources of increased human exposure to naturally occurring radioactive materials. A methodology was developed to assess the radiological impact due to natural radiation background. The developed research was applied to a specific case study, the Sines coal-fired power plant, located in the southwest coastline of Portugal. Gamma radiation measurements were carried out with two different instruments: a sodium iodide scintillation detector counter (SPP2 NF, Saphymo) and a gamma ray spectrometer with energy discrimination (Falcon 5000, Canberra). Two circular survey areas were defined within 20 km of the power plant. Forty relevant measurements points were established within the sampling area: 15 urban and 25 suburban locations. Additionally, ten more measurements points were defined, mostly at the 20-km area. The registered gamma radiation varies from 20 to 98.33 counts per seconds (c.p.s.) corresponding to an external gamma exposure rate variable between 87.70 and 431.19 nGy/h. The highest values were measured at locations near the power plant and those located in an area within the 6 and 20 km from the stacks. In situ gamma radiation measurements with energy discrimination identified natural emitting nuclides as well as their decay products (Pb-212, Pb-2142, Ra-226, Th-232, Ac-228, Th-234, Pa-234, U- 235, etc.). According to the results, an influence from the stacks emissions has been identified both qualitatively and quantitatively. The developed methodology accomplished the lack of data in what concerns to radiation rate in the vicinity of Sines coal-fired power plant and consequently the resulting exposure to the nearby population. (authors)

  19. Natural variations in calcium isotope composition as a monitor of bone mineral balance in humans.

    NASA Astrophysics Data System (ADS)

    Skulan, J.; Anbar, A.; Thomas, B.; Smith, S.

    2004-12-01

    The skeleton is the largest reservoir of calcium in the human body and is responsible for the short term control of blood levels of this element. Accurate measurement of changes in bone calcium balance is critical to understanding how calcium metabolism responds to physiological and environmental changes and, more specifically, to diagnosing and evaluating the effectiveness of treatments for osteoporosis and other serious calcium-related disorders. It is very difficult to measure bone calcium balance using current techniques, however, because these techniques rely either on separate estimates of bone resorption and formation that are not quantitatively comparable, or on complex and expensive studies of calcium kinetics using administered isotopic tracers. This difficulty is even more apparent and more severe for measurements of short-term changes in bone calcium balance that do not produce detectable changes in bone mineral density. Calcium isotopes may provide a novel means of addressing this problem. The foundation of this isotope application is the ca. 1.3 per mil fractionation of calcium during bone formation, favoring light calcium in the bone. This fractionation results in a steady-state isotopic offset between calcium in bone and calcium in soft tissues, blood and urine. Perturbations to this steady state due to changes in the net formation or resorption of bone should be reflected in changes in the isotopic composition of soft tissues and fluids. Here we present evidence that easily detectable shifts in the natural calcium isotope composition of human urine rapidly reflect changes in bone calcium balance. Urine from subjects in a 17-week bed rest study was analyzed for calcium isotopic composition. Bed rest promotes net resorption of bone, shifting calcium from bone to soft tissues, blood and urine. The calcium isotope composition of patients in this study shifted toward lighter values during bed rest, consistent with net resorption of isotopically-light bone calcium. In contrast, little shift was seen in patients who exercised during bed rest, consistent with the expectation that exercise should inhibit bone resorption. Most intriguingly, an opposite-sense shift was seen in patients who were administered aledronate, a drug which inhibits bone resorption. We hypothesize that these patients entered a state of positive bone mineral balance despite initiation of bed rest. Comparison of isotopic data with measurements of bone mineral density and metabolic markers of bone metabolism confirms that the calcium isotope composition of urine reflects changes in bone mineral balance. Calcium isotope analysis of urine and soft tissues may provide information on bone mineral balance that is in important respects better than that available from other techniques, and illustrates the usefulness of applying geochemical techniques to biomedical problems.

  20. 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...

  1. 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...

  2. First detection of the presence of naturally occurring grapevine downy mildew in the field by a fluorescence-based method.

    PubMed

    Latouche, Gwendal; Debord, Christian; Raynal, Marc; Milhade, Charlotte; Cerovic, Zoran G

    2015-10-01

    Early detection of fungal pathogen presence in the field would help to better time or avoid some of the fungicide treatments used to prevent crop production losses. We recently introduced a new phytoalexin-based method for a non-invasive detection of crop diseases using their fluorescence. The causal agent of grapevine downy mildew, Plasmopara viticola, induces the synthesis of stilbenoid phytoalexins by the host, Vitis vinifera, early upon infection. These stilbenoids emit violet-blue fluorescence under UV light. A hand-held solid-state UV-LED-based field fluorimeter, named Multiplex 330, was used to measure stilbenoid phytoalexins in a vineyard. It allowed us to non-destructively detect and monitor the naturally occurring downy mildew infections on leaves in the field. PMID:26293623

  3. Polarization dependent two-photon absorption spectroscopy on a naturally occurring biomarker (curcumin) in solution: A theoretical-experimental study

    NASA Astrophysics Data System (ADS)

    Tiburcio-Moreno, Jose A.; Alvarado-Gil, J. J.; Diaz, Carlos; Echevarria, Lorenzo; Hernández, Florencio E.

    2013-09-01

    We report on the theoretical-experimental analysis of the two-photon absorption (TPA) and two-photon circular-linear dichroism (TPCLD) spectra of (1E,6E)-1,7-bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione (curcumin) in Tetrahydrofuran (THF) solution. The measurement of the full TPA spectrum of this molecule reveals a maximum TPA cross-section at 740 nm, i.e. more than 10 times larger than the maximum reported in the literature at 800 nm for the application of curcumin in bioimaging. The TPCLD spectrum exposes the symmetry of the main excited-states involved in the two-photon excitation process. TD-DFT calculations support the experimental results. These outcomes are expected to expand the application of natural-occurring dyes in bioimaging.

  4. Investigation of the environmental impacts of naturally occurring radionuclides in the processing of sulfide ores for gold using gamma spectrometry.

    PubMed

    Gbadago, J K; Faanhof, A; Darko, E O; Schandorf, C

    2011-09-01

    The possible environmental impacts of naturally occurring radionuclides on workers and a critical community, as a result of milling and processing sulfide ores for gold by a mining company at Bogoso in the western region of Ghana, have been investigated using gamma spectroscopy. Indicative doses for the workers during sulfide ore processing were calculated from the activity concentrations measured at both physical and chemical processing stages. The dose rate, annual effective dose equivalent, radium equivalent activity, external and internal hazard indices, and radioactivity level index for tailings, for the de-silted sediments of run-off from the vicinity of the tailings dam through the critical community, and for the soils of the critical community's basic schools were calculated and found to be lower than their respective permissible limits. The environmental impact of the radionuclides is therefore expected to be low in this mining environment. PMID:21865616

  5. Host-guest Inclusion Complexes between Mitiglinide and the Naturally Occurring Cyclodextrins α, β, and γ: A Theoretical Approach

    PubMed Central

    Al Azzam, Khaldun Mohammad; Muhammad, Ermafatiha

    2015-01-01

    Purpose: The present study is aimed to study the host-guest inclusion complexation of the naturally occurring cyclodextrins (CDs), namely; (α-CD,β-CD, and γ-CD) with mitiglinide (MIT). Methods: Host-guest inclusion complexation was simulated using semi-empirical PM3 method. Results: The obtained results clearly indicate that the complexes formed are energetically favored in the presence of γ-CD (Ecomp = -17.884 kcal/mol) of the optimal configurations of (1:1) MIT/γ-CD inclusion complexes. Moreover, the results obtained reveal that the formation of more stable MIT/γ-CD complex compared to MIT/α-CD or MIT/β-CD complexes is primarily due to differences in intermolecular hydrogen bonding. Conclusion: The present theoretical results may be informative to scientists who are devoting themselves to developing effective methods for enhancing the drug solubility. PMID:26236670

  6. Vincristine modulates the expression of Ki67 and apoptosis in naturally occurring canine transmissible venereal tumor (TVT).

    PubMed

    Özalp, G R; Zik, B; Bastan, A; Peker, S; Özdemir-Salci, E S; Bastan, I; Darbaz, I; Salar, S; Karakas, K

    2012-07-01

    We investigated eight adult dogs that were brought to veterinary clinics with a history of transmissible venereal tumors (TVT). Our goal was to demonstrate the occurrence of apoptosis and the cessation of cell proliferation at every phase of scheduled chemotherapy for naturally occurring TVT. Tissue samples were collected immediately after weekly treatments with vincristine sulfate and processed for histological purposes. Sections 5 μm thick were stained by the TUNEL reaction for apoptosis and immunostained for Ki67 as a proliferation marker. We observed that after vincristine applications, tumor cell proliferation ceased and apoptosis increased. Ki67 HSCORE values were significantly lowered after the first and second treatments with the chemotherapeutic agent compared to controls, whereas TUNEL HSCORE values were significantly higher after two applications of vincristine compared to controls. Our results suggest that scheduled vincristine sulfate applications stabilize the induction of tumor regression by inducing apoptosis and preventing cell proliferation. PMID:22404564

  7. A method for the determination of vanadium and iron oxidation states in naturally occurring oxides and silicates

    USGS Publications Warehouse

    Wanty, R.B.; Goldhaber, M.B.

    1985-01-01

    A valence-specific analytical method for determining V3+ in ore minerals has been developed that involves two steps: dissolution of a mineral sample without disturbing the V3+/Vtot ratio, followed by determination of V3+ in the presence of V4+. The samples are dissolved in a mixture of hydrofluoric and sulphuric acids at 100?? in Teflon-lined reaction vessels. Tervalent vanadium is then determined colorimetrically by formation of a V3+-thiocyanate complex in aqueous-acetone medium. Fe3+ is measured semi-quantitatively in the same solution. The method has been tested with two naturally occurring samples containing vanadium and iron. The results obtained were supported by those obtained by other methods, including electron spin resonance spectroscopy, thermogravimetric analysis, and Mo??ssbauer spectroscopy. ?? 1985.

  8. The atomic weight and isotopic composition of boron and their variation in nature

    SciTech Connect

    Holden, N.E.

    1993-08-01

    The boron isotopic composition and atomic weight value and their variation in nature are reviewed. Questions are raised about the previously recommended value and the uncertainty for the atomic weight. The problem of what constitutes an acceptable range for normal material and what should then be considered geologically exceptional is discussed. Recent measurements make some previous decisions in need of re-evaluation.

  9. The Effect of Naturally Occurring Chronic Kidney Disease on the Micro-Structural and Mechanical Properties of Bone

    PubMed Central

    Meltzer, Hagar; Milrad, Moran; Brenner, Ori; Atkins, Ayelet; Shahar, Ron

    2014-01-01

    Chronic kidney disease (CKD) is a growing public health concern worldwide, and is associated with marked increase of bone fragility. Previous studies assessing the effect of CKD on bone quality were based on biopsies from human patients or on laboratory animal models. Such studies provide information of limited relevance due to the small size of the samples (biopsies) or the non-physiologic CKD syndrome studied (rodent models with artificially induced CKD). Furthermore, the type, architecture, structure and biology of the bone of rodents are remarkably different from human bones; therefore similar clinicopathologic circumstances may affect their bones differently. We describe the effects of naturally occurring CKD with features resembling human CKD on the skeleton of cats, whose bone biology, structure and composition are remarkably similar to those of humans. We show that CKD causes significant increase of resorption cavity density compared with healthy controls, as well as significantly lower cortical mineral density, cortical cross-sectional area and cortical cross-sectional thickness. Young's modulus, yield stress, and ultimate stress of the cortical bone material were all significantly decreased in the skeleton of CKD cats. Cancellous bone was also affected, having significantly lower trabecular thickness and bone volume over total volume in CKD cats compared with controls. This study shows that naturally occurring CKD has deleterious effects on bone quality and strength. Since many similarities exist between human and feline CKD patients, including the clinicopathologic features of the syndrome and bone microarchitecture and biology, these results contribute to better understanding of bone abnormalities associated with CKD. PMID:25333360

  10. Naturally occurring hypothermia is more advantageous than fever in severe forms of lipopolysaccharide- and Escherichia coli-induced systemic inflammation

    PubMed Central

    Liu, Elaine; Lewis, Kevin; Al-Saffar, Hiba; Krall, Catherine M.; Singh, Anju; Kulchitsky, Vladimir A.; Corrigan, Joshua J.; Simons, Christopher T.; Petersen, Scott R.; Musteata, Florin M.; Bakshi, Chandra S.; Romanovsky, Andrej A.; Sellati, Timothy J.

    2012-01-01

    The natural switch from fever to hypothermia observed in the most severe cases of systemic inflammation is a phenomenon that continues to puzzle clinicians and scientists. The present study was the first to evaluate in direct experiments how the development of hypothermia vs. fever during severe forms of systemic inflammation impacts the pathophysiology of this malady and mortality rates in rats. Following administration of bacterial lipopolysaccharide (LPS; 5 or 18 mg/kg) or of a clinical Escherichia coli isolate (5 × 109 or 1 × 1010 CFU/kg), hypothermia developed in rats exposed to a mildly cool environment, but not in rats exposed to a warm environment; only fever was revealed in the warm environment. Development of hypothermia instead of fever suppressed endotoxemia in E. coli-infected rats, but not in LPS-injected rats. The infiltration of the lungs by neutrophils was similarly suppressed in E. coli-infected rats of the hypothermic group. These potentially beneficial effects came with costs, as hypothermia increased bacterial burden in the liver. Furthermore, the hypotensive responses to LPS or E. coli were exaggerated in rats of the hypothermic group. This exaggeration, however, occurred independently of changes in inflammatory cytokines and prostaglandins. Despite possible costs, development of hypothermia lessened abdominal organ dysfunction and reduced overall mortality rates in both the E. coli and LPS models. By demonstrating that naturally occurring hypothermia is more advantageous than fever in severe forms of aseptic (LPS-induced) or septic (E. coli-induced) systemic inflammation, this study provides new grounds for the management of this deadly condition. PMID:22513748

  11. Naturally Occurring Variation in the Glutathione-S-Transferase 4 Gene Determines Neurodegeneration After Traumatic Brain Injury

    PubMed Central

    Ström, Mikael; Lindblom, Rickard; Aeinehband, Shahin; Bellander, Bo-Michael; Nyengaard, Jens R.; Lidman, Olle; Piehl, Fredrik

    2013-01-01

    Abstract Aim: Genetic factors are important for outcome after traumatic brain injury (TBI), although exact knowledge of relevant genes/pathways is still lacking. We here used an unbiased approach to define differentially activated pathways between the inbred DA and PVG rat strains. The results prompted us to study further if a naturally occurring genetic variation in glutathione-S-transferase alpha 4 (Gsta4) affects the outcome after TBI. Results: Survival of neurons after experimental TBI is increased in PVG compared to the DA strain. Global expression profiling analysis shows the glutathione metabolism pathway to be the most regulated between the strains, with increased Gsta4 in PVG among top regulated transcripts. A