WorldWideScience

Sample records for mtbe chez mycobacterium

  1. Catabolism of methyl ter-butyl ether (MTBE): characterization of the enzymes of Mycobacterium austroafricanum IFP 2012 involved in MTBE degradation; Catabolisme du methyl tert-butyl ether (MTBE): caracterisation des enzymes impliquees dans la degradation du MTBE chez Mycobacterium austroafricanum IFP 2012

    Energy Technology Data Exchange (ETDEWEB)

    Lopes Ferreira, N

    2005-11-15

    Methyl tert-butyl ether (MTBE) is added to gasoline to meet the octane index requirement. its solubility in water and its poor biodegradability made the use of MTBE a great environmental concern, particularly regarding aquifers. We previously isolated M austroafricanum IFP 2012 able to use MTBE as a sole source of carbon and energy and the MTBE pathway was partially characterized. In the present study, which aimed at isolating the genes involved in MTBE biodegradation in order to use them for estimation of MTBE biodegradation capacities in contaminated environment, we isolated a new M. austroafricanum strain, IFP 2015. A new degradation intermediate, the 2-methyl 1,2-propane-diol (2-M1,2-PD), the product of tert-butanol (TBA) oxidation, was identified. We also determined the enzymes induced during growth of M. austroafricanum IFP 2012 on MTBF. Then, using the tools of protein analysis and of molecular biology, we isolated and cloned the mpd genes cluster in the plasmid pCL4D. Heterologous expression of the recombinant plasmid in M smegmatis tmc2 155, showed the involvement of an 2-M1,2-PD dehydrogenase (MpdB) and a hydroxy-iso-butyr-aldehyde dehydrogenase (MpdC), encoded by mpdB and mpdC, respectively. Both enzymes were responsible for the conversion of 2-M 1,2-PD to hydroxy-isobutyric acid (HIBA). A further survey of different M austroafricanum strains, including IFP 2012, IFP 2015 and JOBS (ex-M vaccae) showed the link between the ability to grow on C{sub 2} to C{sub 16} n-alkanes and the MTBE and TBA degradation capacities. The alkB gene was partially sequenced in all these strains. Expression of alkB was demonstrated in M. austroafricanum IFP 2012 after growth on propane, hexane, hexadecane and TBA. Finally, we identified 2-propanol as the intermediate of HIBA degradation. The gene encoding the 2-propanol:p-N,N'-dimethyl-4-nitroso-aniline (NDMA) oxidoreductase was detected M austroafricanum IFP 2012. (author)

  2. Catabolism of methyl ter-butyl ether (MTBE): characterization of the enzymes of Mycobacterium austroafricanum IFP 2012 involved in MTBE degradation; Catabolisme du methyl tert-butyl ether (MTBE): caracterisation des enzymes impliquees dans la degradation du MTBE chez Mycobacterium austroafricanum IFP 2012

    Energy Technology Data Exchange (ETDEWEB)

    Lopes Ferreira, N.

    2005-11-15

    Methyl tert-butyl ether (MTBE) is added to gasoline to meet the octane index requirement. its solubility in water and its poor biodegradability made the use of MTBE a great environmental concern, particularly regarding aquifers. We previously isolated M austroafricanum IFP 2012 able to use MTBE as a sole source of carbon and energy and the MTBE pathway was partially characterized. In the present study, which aimed at isolating the genes involved in MTBE biodegradation in order to use them for estimation of MTBE biodegradation capacities in contaminated environment, we isolated a new M. austroafricanum strain, IFP 2015. A new degradation intermediate, the 2-methyl 1,2-propane-diol (2-M1,2-PD), the product of tert-butanol (TBA) oxidation, was identified. We also determined the enzymes induced during growth of M. austroafricanum IFP 2012 on MTBF. Then, using the tools of protein analysis and of molecular biology, we isolated and cloned the mpd genes cluster in the plasmid pCL4D. Heterologous expression of the recombinant plasmid in M smegmatis tmc2 155, showed the involvement of an 2-M1,2-PD dehydrogenase (MpdB) and a hydroxy-iso-butyr-aldehyde dehydrogenase (MpdC), encoded by mpdB and mpdC, respectively. Both enzymes were responsible for the conversion of 2-M 1,2-PD to hydroxy-isobutyric acid (HIBA). A further survey of different M austroafricanum strains, including IFP 2012, IFP 2015 and JOBS (ex-M vaccae) showed the link between the ability to grow on C{sub 2} to C{sub 16} n-alkanes and the MTBE and TBA degradation capacities. The alkB gene was partially sequenced in all these strains. Expression of alkB was demonstrated in M. austroafricanum IFP 2012 after growth on propane, hexane, hexadecane and TBA. Finally, we identified 2-propanol as the intermediate of HIBA degradation. The gene encoding the 2-propanol:p-N,N'-dimethyl-4-nitroso-aniline (NDMA) oxidoreductase was detected M austroafricanum IFP 2012. (author)

  3. Degradation of a recalcitrant xenobiotic compound: methyl tert-butyl ether (MTBE) metabolism by mycobacterium austroafricanum; Degradation d'un compose xenobiotique recalcitrant: metabolisme du methyl tert-butyl ether (MTBE) par mycobacterium austroafricanum IFP 2012

    Energy Technology Data Exchange (ETDEWEB)

    Francois, A

    2002-11-01

    Methyl tert-butyl ether (MTBE) is introduced up to 15% (vol/vol) in gasoline in order to obtain a good octane number and to prevent carbon monoxide emissions. However, as a consequence of storage tanks leakage, MTBE became one of the major pollutants of aquifers because of its very low biodegradability. The present study aimed at investigating the biodegradation of MTBE by Mycobacterium austroafricanum IFP 2012. The MTBE metabolic pathway was partially elucidated owing to the identification of some intermediates (tert-butyl formate (TBF), tert-butyl alcohol (TBA), a-hydroxy-isobutyric acid and acetone) and some enzymatic activities (MTBE/TBA monooxygenase (non hemic and inducible), TBF esterase, 2-propanol: NDMA oxidoreductase and another monooxygenase involved in acetone degradation). The involvement of TBF and the requirement of cobalt could be explanations for the low natural attenuation of MTBE; whereas the methoxy group does not seem to be implicated. (author)

  4. Degradation of a recalcitrant xenobiotic compound: methyl tert-butyl ether (MTBE) metabolism by mycobacterium austroafricanum; Degradation d'un compose xenobiotique recalcitrant: metabolisme du methyl tert-butyl ether (MTBE) par mycobacterium austroafricanum IFP 2012

    Energy Technology Data Exchange (ETDEWEB)

    Francois, A.

    2002-11-01

    Methyl tert-butyl ether (MTBE) is introduced up to 15% (vol/vol) in gasoline in order to obtain a good octane number and to prevent carbon monoxide emissions. However, as a consequence of storage tanks leakage, MTBE became one of the major pollutants of aquifers because of its very low biodegradability. The present study aimed at investigating the biodegradation of MTBE by Mycobacterium austroafricanum IFP 2012. The MTBE metabolic pathway was partially elucidated owing to the identification of some intermediates (tert-butyl formate (TBF), tert-butyl alcohol (TBA), a-hydroxy-isobutyric acid and acetone) and some enzymatic activities (MTBE/TBA monooxygenase (non hemic and inducible), TBF esterase, 2-propanol: NDMA oxidoreductase and another monooxygenase involved in acetone degradation). The involvement of TBF and the requirement of cobalt could be explanations for the low natural attenuation of MTBE; whereas the methoxy group does not seem to be implicated. (author)

  5. Effects of gasoline components on MTBE and TBA cometabolism by Mycobacterium austroafricanum JOB5.

    Science.gov (United States)

    House, Alan J; Hyman, Michael R

    2010-07-01

    In this study we have examined the effects of individual gasoline hydrocarbons (C(5-10,12,14) n-alkanes, C(5-8) isoalkanes, alicyclics [cyclopentane and methylcyclopentane] and BTEX compounds [benzene, toluene, ethylbenzene, m-, o-, and p-xylene]) on cometabolism of methyl tertiary butyl ether (MTBE) and tertiary butyl alcohol (TBA) by Mycobacterium austroafricanum JOB5. All of the alkanes tested supported growth and both MTBE and TBA oxidation. Growth on C(5-8) n-alkanes and isoalkanes was inhibited by acetylene whereas growth on longer chain n-alkanes was largely unaffected by this gas. However, oxidation of both MTBE and TBA by resting cells was consistently inhibited by acetylene, irrespective of the alkane used as growth-supporting substrate. A model involving two separate but co-expressed alkane-oxidizing enzyme systems is proposed to account for these observations. Cyclopentane, methylcyclopentane, benzene and ethylbenzene did not support growth but these compounds all inhibited MTBE and TBA oxidation by alkane-grown cells. In the case of benzene, the inhibition was shown to be due to competitive interactions with both MTBE and TBA. Several aromatic compounds (p-xylene > toluene > m-xylene) did support growth and cells previously grown on these substrates also oxidized MTBE and TBA. Low concentrations of toluene (TBA oxidation by alkane-grown cells whereas higher concentrations were inhibitory. The effects of acetylene suggest strain JOB5 also has two distinct toluene-oxidizing activities. These results have been discussed in terms of their impact on our understanding of MTBE and TBA cometabolism and the enzymes involved in these processes in mycobacteria and other bacteria.

  6. Limitations in MTBE biodegradation; Etapes limitantes dans la biodegradation du MTBE

    Energy Technology Data Exchange (ETDEWEB)

    Fayolle, F.; Francois, A.; Garnier, L.; Godefroy, D.; Mathis, H.; Piveteau, P.; Monot, F. [Institut Francais du Petrole (IFP), Dept. Biotechnologie et Chimie de la Biomasse, 92 - Rueil-Malmaison (France)

    2003-08-01

    The methyl tert-butyl ether (MTBE) metabolic pathway was partially elucidated in Mycobacterium austroafricanum IFP 2012 by identifying the degradation intermediates. Several enzymatic activities were specifically induced during growth on MTBE. Among those required for the first steps of MTBE degradation to tert-butyl alcohol (TBA), the same monooxygenase was responsible for the oxidation of both MTBE and TBA, with a low affinity for TBA (Km = 1.1 mM). An esterase was involved in the hydrolysis of tert-butyl formate (TBF). The slowness of the degradation of MTBE by M. austroafricanum IFP 2012 was the result of complex interactions, especially the negative effect of TBF formed during MTBE oxidation on the MTBE/TBA mono-oxygenase and the absence of TBA oxidation in the presence of residual MTBE. Moreover, concerning the downstream steps of MTBE metabolism, Co{sup ++} ions were required for the degradation of 2-hydroxy-isobutyric acid (HIBA) formed by oxidation of TBA as shown by the low growth yield on HIBA in the absence of cobalt. (authors)

  7. THE PARADOXES OF MTBE

    Science.gov (United States)

    A widely used gasoline additive, methyl tertiary butyl ether (MTBE), has been controversial, in part because of concerns about potential inhalation health effects and more recently because of added concerns about water contamination. Although many of the issues related to MTBE ha...

  8. Phytoremediation of MTBE

    International Nuclear Information System (INIS)

    Newman, L.

    2002-01-01

    'Full text:' Phytoremediation, or the use of plants to remediate contaminants, is one of the new technologies being considered for MTBE remediation. While the high solubility of MTBE results in rapid uptake in the plant, little is known about the metabolic fate of MTBE in the plant system. In part, this is because of the lack of analytical methods that will allow the identification and characterization of low levels of metabolites when examined against a plant cell background. This talk will present a review of the work from several laboratories that are looking into phytoremediation of MTBE as well as the work done at the University of Washington and the University of South Carolina looking at the fate of MTBE in the plant system. Results from several experiments, both in the laboratory and from field installations, will be presented. (author)

  9. A review of treatment technologies for MTBE

    International Nuclear Information System (INIS)

    Bass, D.

    1995-01-01

    Available treatment technologies for methyl tertiary butyl ether (MTBE) contamination in soil, groundwater, and recovered groundwater are reviewed and assessed. MTBE contamination is becoming an important issue due to the increasing prevalence and regulation of this gasoline additive. In addition, MTBE is more soluble and more mobile in groundwater than most hydrocarbons, so it is usually the first gasoline constituent to reach sensitive receptors. Treatment of MTBE is complicated by its Henry's constant, which is lower than most other gasoline constituents. Furthermore, evidence of biodegradability of MTBE is mixed, and MTBE does not degrade rapidly abiotically. Groundwater pumping is usually employed to contain and collect MTBE-contaminated groundwater, often successfully because of its high aqueous solubility. Air sparging/soil vapor extraction is also successfully employed to treat MTBE, but its effectiveness is reduced by the low Henry's constant of MTBE. Sparging and other aerobic bioremediation approaches are hampered by the poor biodegradability of MTBE. Oxidation technologies, such as ozone injection, hold promise for rapid in situ remediation of MTBE. Treatment of recovered groundwater contaminated with MTBE is also problematic. MTBE adsorbs poorly to granular activated carbon; advanced oxidation processes are effective on MTBE, but entail high capital and operating costs; bioreactors are of questionable effectiveness on MTBE. Air stripping is usually the most cost-effective treatment technology for MTBE so long as the off gas from the air stripper can be discharged without treatment. However, off gas treatment is expensive, so groundwater is sometimes heated to reduce the requirement for stripping air

  10. MTBE: effects on soil and groundwater resources

    National Research Council Canada - National Science Library

    Jacobs, James J; Guertin, Jacques; Herron, Christy

    2001-01-01

    ... Properties of MTBE); Dr. Jacques Guertin, Toxicologist/ Chemist (Toxicity, Health Effects, and Taste and Odor Thresholds of MTBE; Appendix I, Toxicity of MTBE: Human Health Risk Calculations); Fred Stanin, Hydrogeologist (Transport and Fate of MTBE in the Environment); Dr. Paul Fahrenthold, Remediation Engineer/Chemist (Detection and Treatment of M...

  11. Characterization of arene di-oxygenases involved in polycyclic aromatic hydrocarbons biodegradation in Mycobacterium sp. 6PY1; Caracterisation d'arene dioxygenases impliquees dans la biodegradation des hydrocarbures aromatiques polycycliques chez Mycobacterium sp. 6PY1

    Energy Technology Data Exchange (ETDEWEB)

    Kuony, S.

    2005-06-15

    This thesis deals with the bacterial biodegradation of pollutants called polycyclic aromatic hydrocarbons (PAHs). The bacterium Mycobacterium sp. 6PY1 was isolated from a polluted soil for its ability to use pyrene, a 4-ring PAH, as sole source of carbon and energy. To learn about the pyrene metabolic pathway, the identification of the enzymes involved in this process has been undertaken using a proteomic approach. This approach revealed the occurrence of two ring-hydroxylating di-oxygenases in strain 6PY1, which could catalyze the initial attack of pyrene. The goal of this study was to clone the genes encoding the di-oxygenases identified in Mycobacterium sp. 6PY1, over-express these genes in an heterologous system in order to facilitate the purification of the corresponding enzymes, and determine the biochemical and catalytic properties of these enzymes. The pdoA1B1 genes encoding the terminal component of a di-oxygenase were cloned and over-expressed in Escherichia coli. The catalytic properties of this enzyme, called Pdo1, were determined in vivo by measuring the oxidation products of 2- to 4-ring PAHs by gas chromatography coupled to mass spectrometry (GC-MS). Analysis of the selectivity of the enzyme, as determined using GC-MS, showed that Pdo1 preferentially oxidized 3- or 4-ring PAHs, including phenanthrene and pyrene, but was inactive on di-aromatic compounds such as naphthalene and biphenyl. Pdo1 was unstable and was therefore purified in inactive form. The genes encoding a second di-oxygenase component were found in a locus containing two other catabolic genes. The pdoA2B2 genes encoded an enzyme called Pdo2 showing a narrow specificity towards 2- to 3-ring PAHs, and a high preference for phenanthrene. Pdo2 is an a3{beta}3 hexamer, containing [2Fe-2S] Rieske clusters which confer it a characteristic absorbance spectrum. A third set of genes possibly encoding another di-oxygenase was discovered in the genome of Mycobacterium sp. 6PY1. This set is closely

  12. Biodegradation of MTBE in reactors

    DEFF Research Database (Denmark)

    Waul, Christopher Kevin

    2007-01-01

    The fuel oxygenate methyl tert-butyl ether (MTBE) was first introduced in the 1970’s to improve gasoline combustion efficiency and reduce emission of harmful gases. However, it has caused groundwater contamination in Denmark and in many locations worldwide through accidental releases from leaking...... anaerobic conditions. Overall, the studies showed that despite the effects of competition, fixed film bioreactors can be successfully applied to remove MTBE from ground water to meet the current Danish drinking water regulatory requirement of 5 ppb or even lower....

  13. MTBE experts' discussion: Environmental pollution from MTBE fuel additives. Proceedings; MTBE-Fachgespraech: Umweltbelastungen durch die Nutzung von MTBE (Methyl-tertiaer-butylether) als Kraftstoffzusatz. Tagungsband

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    MTBE is a volatile, water-soluble, oxygen-containing liquid with a high octane rating. It hardly absorbs to the soil matrix, is hardly degradable by biological means, and moves in groundwater at practically the same speed as the groundwater itself. This makes it an important groundwater hazard. The main problem is the low taste and smell threshold concentration of MTBE, because of which contaminated water is unfit for drinking. MTBE has been used as a fuel additive in the USA since the seventies and in Germany since the eighties for a better antiknock rating. MTBE concentrations depend on the fuel quality, ranging from 0.3 percent in normal gasoline and 1.6 percent in super gasoline to 6-12 percent by volume in SuperPlus and Optimax fuels. At this conference, which comprised nine lectures and a round of detailed discussions, measured concentrations of MTBE in air, precipitations, surface water and groundwater were presented, and the possibilities of modelling were discussed. The attendants of the meeting agreed that in view of the available data and at the present state of knowledge concerning the sources and fate of MTBE in environmental media, MTBE cannot be excluded as a groundwater pollutant. (orig.) [German] MTBE ist eine leichtfluechtige, gut wasserloesliche, sauerstoffhaltige Fluessigkeit mit hoher Oktanzahl. Es sorbiert fast nicht an die Bodenmatrix, ist sehr schlecht biologisch abbaubar und bewegt sich im Grundwasser praktisch mit der gleichen Geschwindigkeit wie das Grundwasser selbst. Aufgrund dieser Eigenschaften stellt MTBE eine Gefahr fuer das Grundwasser dar. Problematisch aus Sicht der Wasserversorgung ist die niedrige Geruchs- und Geschmacksschwelle von MTBE, weshalb kontaminiertes Wasser nicht mehr als Trinkwasser brauchbar ist. MTBE wird seit Mitte der 70er Jahre in den USA und seit Anfang der 80er Jahre in Deutschland dem Benzin zugesetzt, um die Klopffestigkeit zu verbessern. Der MTBE-Gehalt haengt von der Benzin-Qualitaet ab: Waehrend

  14. Biodegradation of MTBE in reactors

    OpenAIRE

    Waul, Christopher Kevin; Arvin, Erik; Schmidt, Jens Ejbye

    2007-01-01

    The fuel oxygenate methyl tert-butyl ether (MTBE) was first introduced in the 1970’s to improve gasoline combustion efficiency and reduce emission of harmful gases. However, it has caused groundwater contamination in Denmark and in many locations worldwide through accidental releases from leaking underground gasoline storage tanks and pipelines. Both laboratory experiments and mathematical computer models were used to acquire knowledge on the scientific and engineering aspects related to the ...

  15. Degradation of MTBE and TBA by a new isolate from MTBE-contaminated soil.

    Science.gov (United States)

    Zhang, Rui-Ling; Huang, Guo-Qiang; Lian, Jing-Yan; Li, Xin-Gang

    2007-01-01

    Methyl tert-butyl ether (MTBE), a gasoline additive, possesses serious problems to the environmental health. In the present study, a bacterial culture named A-3 which could effectively degrade MTBE was isolated from the MTBE contaminated soil. The isolate was identified as Chryseobacterium sp., a new species capable of degrading MTBE. In order to enhance its degradation ability, selected environment factors were investigated. The results showed that the optimal temperature was in the range of 25-30 degrees C, the pH was 7.0, the inoculum size was 2 x 10(8) CFU/ml and the optimal concentration of MTBE was from 50 to 100 mg/L. The maximum MTBE utilization rate (upsilon(max)) was 102 nmol MTBE/(mg cell protein x h). Furthermore, it was found that the isolate could also degrade tert-butyl alcohol (TBA). The degradation rates of TBA were much faster than those of MTBE. The additional TBA would lead to the decrease of the initial MTBE degradation rate and the inhibitory effect of TBA increased with the increase of TBA concentration. Similar protein profiles at least seven peptides were demonstrated after SDS-PAGE analysis of crude extracts obtained from the cells growing in MTBE and TBA culture.

  16. BIODEGRADATION OF MTBE BY A MICROORGANISM CONSORTIUM

    Directory of Open Access Journals (Sweden)

    M. Alimohammadi, A. R. Mesdaghinia, M. Mahmoodi, S. Nasseri, A. H. Mahvi and J. Nouri

    2005-10-01

    Full Text Available Methyl Tert-Butyl Ether (MTBE is one of the ether oxygenates which its use has been increased within the last twenty years. This compound is produced from isobutylene and methanol reaction that is used as octane index enhancer and also increases dissolved oxygen in gasoline and decreases carbon monoxide emission in four phased motors because of better combustion of gasoline. High solubility in water (52 g/L, high vapor pressure (0.54 kg/cm3, low absorption to organic carbon of soil and presence of MTBE in the list of potentially-carcinogens of U.S EPA has made its use of great concern. The culture media used in this study was Mineral Salt Medium (MSM. The study lasted for 236 days and in three different concentrations of MTBE of 200, 5 and 0.8 mg/L. A control sample was also used to compare the results. This research studied the isolation methods of microbial consortium in the MTBE polluted soils in Tehran and Abadan petroleum refinery besides MTBE degradation. The results showed the capability of bacteria in consuming MTBE as carbon source. Final microbial isolation was performed with several microbial passages as well as keeping consortium in a certain amount of MTBE as the carbon source.

  17. MICROCOSM STUDY OF ANAEROBIC BIODEGRADATION OF MTBE AND TBA

    Science.gov (United States)

    Ground water samples collected in at a gasoline spill sites in Orange County, California, suggested that MTBE was being transformed to TBA. In some of the most heavily contaminated wells, the concentration of TBA was higher than the concentration of MTBE (MTBE 2 µg/L and TBA 40,...

  18. Jeux chez les Touaregs

    OpenAIRE

    Bernus, E.

    2012-01-01

    Parmi les jeux pratiqués par les Touaregs, il faut distinguer les jeux sportifs qui opposent deux équipes ou deux hommes, des jeux de société dans un cadre inscrit dans le sable, et les jeux d’esprit, véritables joutes verbales ; enfin, il faut signaler la construction par les enfants de jouets. Un certain nombre de jeux sont connus chez d’autres populations africaines. L’ouvrage de Charles Béart, Jeux et jouets de l’Ouest africain (1955), nous permet d’utiles comparaisons. Il est donc intére...

  19. Role of volatilization in changing TBA and MTBE concentrations at MTBE-contaminated sites.

    Science.gov (United States)

    Eweis, Juana B; Labolle, Eric M; Benson, David A; Fogg, Graham E

    2007-10-01

    Tertiary butyl alcohol (TBA) is commonly found as an impurity in methyl tertiary butyl ether (MTBE) added to gasoline. Frequent observations of high TBA, and especially rising TBA/MTBE concentration ratios, in groundwater at gasoline spill sites are generally attributed to microbial conversion of MTBE to TBA. Typically overlooked is the role of volatilization in the attenuation of these chemicals especially in the vadose zone, which is a source of contamination to groundwater. Here we show that volatilization, particularly through remediation by vapor extraction, can substantially affect the trends in TBA and MTBE concentrations and the respective mass available to impact groundwater aquifers, through the preferential removal of more volatile compounds, including MTBE, and the apparent enrichment of less volatile compounds like TBA. We demonstrate this phenomenon through numerical simulations of remedial-enhanced volatilization. Results show increases in TBA/MTBE concentration ratios consistent with ratios observed in groundwater at gasoline spill sites. Volatilization is an important, and potentially dominant, process that can result in concentration trends similar to those typically attributed to biodegradation.

  20. In Situ Biodegradation of MTBE and TBA

    Science.gov (United States)

    Ground water at most UST spills sites in Kansas contains both MTBE and benzene, and both contaminants must be effectively treated to close the sites. Soil vacuum extraction, and air sparging are common treatment technologies in Kansas. The technologies supply oxygen to support ...

  1. Conversion of methanol and isobutanol to MTBE

    CSIR Research Space (South Africa)

    Nicolaides, CP

    1993-09-24

    Full Text Available Over the resin catalyst Amberlyst 15, and under our reaction conditions, the yield of MTBE (methyl tert-butyl ether), from the reaction of methanol and isobutene, is at a maximum in the temperature rang of 40-60-degrees-C. Slightly higher...

  2. Bioremediation treatment of MTBE and ETBE in contaminated soils

    Directory of Open Access Journals (Sweden)

    Alissara Reungsang

    2006-07-01

    Full Text Available Three Methyl Tertiary Butyl Ether (MTBE degradative consortia were isolated from gasoline-contaminated soil namely: mKMS, mKGS1 and mKGS2. These consortia were tested for the ability to degrade Ethyl Tertiary Butyl Ether (ETBE at the concentration of 100 mg/L and to degrade a mixture of MTBE and ETBE in the Nutrient Broth (NB media at the concentration of 50 mg/L each. The results showed that mKGS1 was the best degraders in which 74% of MTBE, 25% of ETBE and 16% of MTBE and 23% of ETBE in the mixture were degraded, within 30 days. mKGS1 was then further used in the bioaugmentation and biostimulation experiments. Degradation of MTBE increased from 34% to 61% after 70 days when mKGS1 was amended in soil mixed with the combination of MTBE and ETBE (at 50 mg/L each. However, mKGS1 did not significantly help the ETBE degradation when it was amended in soil (biostimulation technique. One percent glucose significantly stimulated the degradation of MTBE by the indigenous microorganisms. The presence of mKGS1 and an addition of 1% glucose as extra carbon source improved the degradation of MTBE, from 42 to 51%, suggesting mKGS1 played an important role in the degradation of MTBE.

  3. Water quality and MTBE water pollution

    International Nuclear Information System (INIS)

    Buiatti, M.; Mascini, M.; Monanni, R.; Filipponi, M.; Piangoloni, A.; Mancini, G.

    2001-01-01

    The research project, here presented, was defined with the aim of evaluating the eventual presence of MTBE and the possible relative impact in water destined to human use; the territorial valence of the project was extended to the competence region n. 4 of the Tuscany water authority (AATO n. 4). University of Florence, ARPAT, AATO n. 4 and Nuove Acque SpA, in this role of manager for the integrated water cycle in the country, have productively contributed to the project [it

  4. Challenges of MTBE development from field butanes

    International Nuclear Information System (INIS)

    Williams, F.

    1991-01-01

    Tenneco Natural Gas Liquids has embarked on a new project to produce Methyl Teritiary Butyl Ether (MTBE) form butanes as have several others. The Clean Air Act will provide the impetus for even more of these plants in the future. In fact, butanes have the potential to go form a surplus product situation today to an important product in the near future. So what follows are our ideas about what the MTBE business looks like form the standpoint of a new producer getting things underway. This paper reports that there are roughly six areas where a potential producer of MTBE or Ethyl Tertiary Butyl Ether (ETBE) for that matter, should have concern. Your planning department should be aware of a source of feedstocks; have adequate storage planned; understand the technology involved and its related cost; be forearmed with an idea of location and its specific market opportunities; be prepared for significant environmental evaluation along with necessary contingency plans; and most importantly display a high degree of optimism as to future markets so as to minimize all of the aforementioned concerns

  5. AEROBIC BIODEGRADATION OF GASOLINE OXYGENATES MTBE AND TBA

    Science.gov (United States)

    MTBE degradation was investigated using a continuously stirred tank reactor (CSTR) with biomass retention (porous pot reactor) operated under aerobic conditions. MTBE was fed to the reactor at an influent concentration of 150 mg/l (1.70 mmol/l). A second identifical rector was op...

  6. REMEDIATION OF MTBE - CONTAMINATED WATER: STUDIES ON THE DEGRADATION OF MTBE INTERMEDIATES USING THE FENTON'S REAGENT

    Science.gov (United States)

    The recent findings of unusual oncentrations of MTBE in groundwater aquifers and surface waters [1] originated most probably from the leaking of underground storage gasoline tanks [2[ has led to a series of judicial and legislative actions, especially in the state of California w...

  7. Bioremediation Potential of MTBE in Water Resources by Eucalyptus Globolus

    Directory of Open Access Journals (Sweden)

    Mohammad Koushafar

    2005-12-01

    Full Text Available Methyl Tertia Butyl Ether (MTBE is an organic compound with widespread use in unleaded gasoline. Although use of MTBE had some environmental advantages, it was soon cleared that this compound has adverse effect on environment and human health. MTBE is highly soluble in water, it binds weakly to soil and doesn’t readily biodegrade in the environments. However it is known as a contaminant in environment specially for groundwater resources. Different methods have been introduced for treatment of MTBE from groundwater. These methods are generally expensive and inefficient. Phytoremediation introduce as an effective and inexpensive technology for removal of MTBE from groundwater and soil. In this paper the ability of  Eucaliptus globules for removal of MTBE from water has been investigated.The Transpiration Stream Concentration Factor (TSCF was used for evaluation of the ability of this plant. The calculated value for TSCF was 0.79 so it can be concluded that MTBE can be absorbed by this plant.

  8. Laboratory evidence of MTBE biodegradation in Borden aquifer material

    Science.gov (United States)

    Schirmer, Mario; Butler, Barbara J.; Church, Clinton D.; Barker, James F.; Nadarajah, Nalina

    2003-02-01

    Mainly due to intrinsic biodegradation, monitored natural attenuation can be an effective and inexpensive remediation strategy at petroleum release sites. However, gasoline additives such as methyl tert-butyl ether (MTBE) can jeopardize this strategy because these compounds often degrade, if at all, at a slower rate than the collectively benzene, toluene, ethylbenzene and the xylene (BTEX) compounds. Investigation of whether a compound degrades under certain conditions, and at what rate, is therefore important to the assessment of the intrinsic remediation potential of aquifers. A natural gradient experiment with dissolved MTBE-containing gasoline in the shallow, aerobic sand aquifer at Canadian Forces Base (CFB) Borden (Ontario, Canada) from 1988 to 1996 suggested that biodegradation was the main cause of attenuation for MTBE within the aquifer. This laboratory study demonstrates biologically catalyzed MTBE degradation in Borden aquifer-like environments, and so supports the idea that attenuation due to biodegradation may have occurred in the natural gradient experiment. In an experiment with batch microcosms of aquifer material, three of the microcosms ultimately degraded MTBE to below detection, although this required more than 189 days (or >300 days in one case). Failure to detect the daughter product tert-butyl alcohol (TBA) in the field and the batch experiments could be because TBA was more readily degradable than MTBE under Borden conditions.

  9. Benzene and MTBE Sorption in Fine Grain Sediments

    Science.gov (United States)

    Leal-Bautista, R. M.; Lenczewski, M. E.

    2003-12-01

    The practice of adding methyl tert-butyl ether (MTBE) to gasoline started in the late 1970s and increased dramatically in the 1990s. MTBE first was added as a substitute for tetra-ethyl lead then later as a fuel oxygenate. Although the use of MTBE has resulted in significant reduction in air pollution, it has become a significant groundwater contaminant due to its high solubility in water, high environmental mobility, and low potential for biodegradation. A recent report (1999-2001) by the Metropolitan Water District of Southern California in collaboration with United State Geological Survey and the Oregon Health and Science University found that MTBE was the second most frequent detected volatile organic compound in groundwater. In Illinois, MTBE has been found in 26 of the 1,800 public water supplies. MTBE has also been blended in Mexico into two types of gasoline sold in the country by the state oil company (PEMEX) but is not monitored in groundwater at this time. Early research on MTBE considered it unable to adsorb to soils and sediments, however, by increasing the organic matter and decreasing the size of the grains (silts or clays) this may increase sorption. The objective of this study is to determine if fine grained materials have the potential for sorption of MTBE due to its high specific surface area (10-700 m 2/g) and potentially high organic matter (0.5-3.8%). The experiment consisted of sorption isotherms to glacial tills from DeKalb, Illinois and lacustrine clays from Chalco, Mexico. Experiments were performed with various concentrations of MTBE and benzene (10, 50, 100, 500 and 1000 ug/L) at 10° C and 25° C. Results showed a range of values for the distribution coefficient (Kd, linear model). At 10° C the Kd value for MTBE was 0.187 mL/g for lacustrine clay while the glacial loess had a value of 0.009 mL/g. The highest Kd values with MTBE were 0.2859 mL/g for organic rich lacustrine clays and 0.014 mL/g for glacial loess at 25° C. The highest

  10. Depistage clinique des infections sexuellement transmissibles chez ...

    African Journals Online (AJOL)

    Depistage clinique des infections sexuellement transmissibles chez les personnes vivant avec le VIH suivies au Centre de Traitement Ambulatoire du Centre National Hospitalier Universitaire Hubert Koutoukou Maga de Cotonou.

  11. Les manifestations cardiovasculaires chez les hemodialyses ...

    African Journals Online (AJOL)

    Le but de l'étude est d'analyser sur une période de 12 mois chez 75 patients en hémodialyse chronique, âgés de 38ans en moyenne, le les aspects cliniques, thérapeutiques et évolutifs des manifestations cardiovasculaires. La prévalence est de 87,20% chez les patients. Les signes fonctionnels les plus fréquents sont la ...

  12. n-Alkane assimilation and tert-butyl alcohol (TBA) oxidation capacity in Mycobacterium austroafricanum strains.

    Science.gov (United States)

    Lopes Ferreira, Nicolas; Mathis, Hugues; Labbé, Diane; Monot, Frédéric; Greer, Charles W; Fayolle-Guichard, Françoise

    2007-06-01

    Mycobacterium austroafricanum IFP 2012, which grows on methyl tert-butyl ether (MTBE) and on tert-butyl alcohol (TBA), the main intermediate of MTBE degradation, also grows on a broad range of n-alkanes (C2 to C16). A single alkB gene copy, encoding a non-heme alkane monooxygenase, was partially amplified from the genome of this bacterium. Its expression was induced after growth on n-propane, n-hexane, n-hexadecane and on TBA but not after growth on LB. The capacity of other fast-growing mycobacteria to grow on n-alkanes (C1 to C16) and to degrade TBA after growth on n-alkanes was compared to that of M. austroafricanum IFP 2012. We studied M. austroafricanum IFP 2012 and IFP 2015 able to grow on MTBE, M. austroafricanum IFP 2173 able to grow on isooctane, Mycobacterium sp. IFP 2009 able to grow on ethyl tert-butyl ether (ETBE), M. vaccae JOB5 (M. austroaafricanum ATCC 29678) able to degrade MTBE and TBA and M. smegmatis mc2 155 with no known degradation capacity towards fuel oxygenates. The M. austroafricanum strains grew on a broad range of n-alkanes and three were able to degrade TBA after growth on propane, hexane and hexadecane. An alkB gene was partially amplified from the genome of all mycobacteria and a sequence comparison demonstrated a close relationship among the M. austroafricanum strains. This is the first report suggesting the involvement of an alkane hydroxylase in TBA oxidation, a key step during MTBE metabolism.

  13. Comparison of an ability to degrade MTBE between mixed culture and monoculture isolated from gasoline contaminated soil

    Directory of Open Access Journals (Sweden)

    Wanpen Virojanakud

    2004-02-01

    Full Text Available Methyl tertiary butyl ether (MTBE is an oxygenated compound used to enhance the octane index of gasoline and replace lead in gasoline. MTBE can reduce air pollution but causes water pollution due to its high water solubility and low sorption to soil and thus can easily contaminate the environment. Biodegradation is one of the promising techniques to reduce MTBE contaminated in the environment and MTBE degrader was proposed as an efficient method used to degrade MTBE. In this study, MTBE degraders were isolated from gasoline contaminated soil and then were evaluated with the hypothesis that MTBE degraders could improve biodegradation of MTBE in soil and mixed culture could degrade MTBE more rapidly than monoculture. Gasoline contaminated soil samples were taken from retail gas stations and a motorcycle repair shop in Khon Kaen University. Isolation of MTBE degrader was conducted by using Basal Salt Medium (BSM containing 200 mg/L of MTBE as a carbon source. Mixed culture of MTBE degrader was successfully isolated under aerobic condition. Morphology study was conducted by streaking isolated mixed culture in solid medium, agar slant and identifying the cells shape under a microscope. It was found that this mixed culture was a gram negative bacteria with 7 different isolates. A comparison of the ability to degrade MTBE between mixed culture and monoculture was investigated in BSM containing 100 mg/L of MTBE. The results indicated that a mixed culture degraded MTBE more rapidly than monoculture i.e. 20% within 14 days. Monoculture, J4 and J7, were the most rapid MTBE degraders among the other monocultures in which they degraded 14% of MTBE in 14 days while monoculture J15 could degrade only 1% of MTBE.This preliminary result suggests that mixed cultures degrade MTBE more efficiently than monoculture.

  14. MTBE inhaled alone and in combination with gasoline vapor: uptake, distribution, metabolism, and excretion in rats.

    Science.gov (United States)

    Benson, J M; Barr, E B; Krone, J R

    2001-05-01

    The purpose of these studies was to extend previous evaluation of methyl tert-butyl ether (MTBE)* tissue distribution, metabolism, and excretion in rats to include concentrations more relevant to human exposure (4 and 40 ppm) and to determine the effects of coinhalation of the volatile fraction of unleaded gasoline on the tissue distribution, metabolism, and excretion of MTBE. Groups of male F344 rats were exposed nose-only for 4 hours to 4, 40, or 400 ppm 14C-MTBE or to 20 or 200 ppm of the light fraction of unleaded gasoline (LFG) containing 4 or 40 ppm 14C-MTBE, respectively. To evaluate the effects of repeated inhalation of LFG on MTBE tissue distribution, metabolism, and excretion, rats were exposed for 4 hours on each of 7 consecutive days to 20 or 200 ppm LFG with MTBE (4 or 40 ppm) followed on the eighth day by a similar exposure to LFG containing 14C-MTBE. Subgroups of rats were evaluated for respiratory parameters, initial body burdens, rates and routes of excretion, and tissue distribution and elimination. The concentrations of MTBE and its chief metabolite, tert-butyl alcohol (TBA), were measured in blood and kidney immediately after exposure, and the major urinary metabolites-2-hydroxyisobutyric acid (IBA) and 2-methyl-1,2-propanediol (2MePD)-were measured in urine. Inhalation of MTBE alone or as a component of LFG had no concentration-dependent effect on respiratory minute volume. The initial body burdens of MTBE equivalents achieved after 4 hours of exposure to MTBE did not increase linearly with exposure concentration. MTBE equivalents rapidly distributed to all tissues examined, with the largest percentages distributed to liver. The observed initial body burden did not increase linearly between 4 and 400 ppm. At 400 ppm, elimination half-times of MTBE equivalents from liver increased and from lung, kidney, and testes decreased compared with the two smaller doses. Furthermore, at 400 ppm the elimination half-time for volatile organic compounds (VOCs

  15. DETERMINING HOW VAPOR PHASE MTBE REACHES GROUND WATER

    Science.gov (United States)

    EPA Region 2 and ORD have funded a RARE project for FY 2005/2006 to evaluate the prospects that MTBE (and other fuel components) in vapors that escape from an underground storage tank (UST) can find its way to ground water produced by monitoring wells at a gasoline filling statio...

  16. Degradation of methyl-tert-butyl ether (MTBE)

    Czech Academy of Sciences Publication Activity Database

    Cajthaml, Tomáš; Baldrian, Petr; Stoychev, I.; Nerud, František

    2004-01-01

    Roč. 53, - (2004), s. 208-209 ISSN 0964-8305. [International Bideterioration and Biodegradation Symposium /12./. Praha, 14.07.2002-18.07.2002] R&D Projects: GA MŠk LN00B030 Institutional research plan: CEZ:AV0Z5020903 Keywords : mtbe Subject RIV: EE - Microbiology, Virology Impact factor: 0.835, year: 2004

  17. MTBE BIOREMEDIATION WITH BIONETS CONTAINING ISOLITE, PMI, SOS ON AIR

    Science.gov (United States)

    Methyl tert-Butyl Ether (MTBE), a gasoline additive, is a persistent and foul tasting contaminant that is more mobile in ground water than BTEX. It is turning up at many American crossroads. This study's objective was to determine if biologically active in situ Bionets could bior...

  18. IS YOUR TBA COMING FROM BIODEGRADATION OF MTBE

    Science.gov (United States)

    MTBE (methyl tertiary butyl ether) is present at high concentrations in ground water at many sites where gasoline has been spilled from underground storage tanks. In addition, TBA (tertiary butyl alcohol) is also present at high concentrations in many of the same ground waters. ...

  19. TBA IN GROUND WATER FROM THE NATURAL BIODEGRADATION OF MTBE

    Science.gov (United States)

    At many UST spills, the concentrations of TBA in ground water are much higher than would be expected from the presence of TBA in the gasoline originally spilled. The ratio of concentrations of TBA to concentrations of MTBE in monitoring wells at gasoline spill sites was compared ...

  20. Economics of integrated MTBE/TAME/DIPE production

    International Nuclear Information System (INIS)

    Denney, R.G.

    1993-01-01

    Because of the 1990 Clean Air Act (CAA), the 1993 demand for oxygenates (i.e. MTBE, TAME, DIPE) for motor gasoline blending in PADD IV and V is estimated to total 166,000 bpd. Existing PADD IV and V oxygenate producers can only supply about 13% of this demand. The shortfall must be supplied from oxygenate producers in PADD III or from Canadian and offshore sources. This paper examines the economics of locating an integrated plant in Southwest Wyoming (PADD IV), to supply approximately 6,800 bpd of the PADD IV and V demand by producing MTBE, TAME, and DIPE from natural gas liquids (NGL). The Southwest Wyoming location offers the advantage of being closer to the PADD IV and V markets than the producers in PADD III and the availability of a relatively inexpensive NGL feedstock that has no other market than the Midwest or US Gulf Coast via MAPCO's NGL pipeline. With these location and feedstock cost advantages, the Southwest Wyoming integrated MTBE, TAME, DIPE plant offers an attractive return on investment and economics comparable to those of a World Scale, 12,500 bpd mixed butane feed MTBE plant in PADD III

  1. TREATMENT OF MTBE-CONTAMINATED WATERS WITH FENTON'S REAGENT

    Science.gov (United States)

    Methyl tertiary-butyl ether (MTBE) has been commonly used as a fuel additive because of its many favorable properties that allow it to improve fuel combustion and reduce resulting concentrations of carbon monoxide and unburnt hydrocarbons. Unfortuantely, increased production a...

  2. Intrinsic bioremediation of MTBE-contaminated groundwater at a petroleum-hydrocarbon spill site

    Science.gov (United States)

    Chen, K. F.; Kao, C. M.; Chen, T. Y.; Weng, C. H.; Tsai, C. T.

    2006-06-01

    An oil-refining plant site located in southern Taiwan has been identified as a petroleum-hydrocarbon [mainly methyl tert-butyl ether (MTBE) and benzene, toluene, ethylbenzene, and xylenes (BTEX)] spill site. In this study, groundwater samples collected from the site were analyzed to assess the occurrence of intrinsic MTBE biodegradation. Microcosm experiments were conducted to evaluate the feasibility of biodegrading MTBE by indigenous microorganisms under aerobic, cometabolic, iron reducing, and methanogenic conditions. Results from the field investigation and microbial enumeration indicate that the intrinsic biodegradation of MTBE and BTEX is occurring and causing the decrease in MTBE and BTEX concentrations. Microcosm results show that the indigenous microorganisms were able to biodegrade MTBE under aerobic conditions using MTBE as the sole primary substrate. The detected biodegradation byproduct, tri-butyl alcohol (TBA), can also be biodegraded by the indigenous microorganisms. In addition, microcosms with site groundwater as the medium solution show higher MTBE biodegradation rate. This indicates that the site groundwater might contain some trace minerals or organics, which could enhance the MTBE biodegradation. Results show that the addition of BTEX at low levels could also enhance the MTBE removal. No MTBE removal was detected in iron reducing and methanogenic microcosms. This might be due to the effects of low dissolved oxygen (approximately 0.3 mg/L) within the plume. The low iron reducers and methanogens (soil) observed in the aquifer also indicate that the iron reduction and methanogenesis are not the dominant biodegradation patterns in the contaminant plume. Results from the microcosm study reveal that preliminary laboratory study is required to determine the appropriate substrates and oxidation-reduction conditions to enhance the biodegradation of MTBE. Results suggest that in situ or on-site aerobic bioremediation using indigenous microorganisms would

  3. Microbial biosafety of pilot-scale bioreactor treating MTBE and TBA-contaminated drinking water supply.

    Science.gov (United States)

    Schmidt, Radomir; Klemme, David A; Scow, Kate; Hristova, Krassimira

    2012-03-30

    A pilot-scale sand-based fluidized bed bioreactor (FBBR) was utilized to treat both methyl tert-butyl ether (MTBE) and tert-butyl alcohol (TBA) from a contaminated aquifer. To evaluate the potential for re-use of the treated water, we tested for a panel of water quality indicator microorganisms and potential waterborne pathogens including total coliforms, Escherichia coli, Salmonella and Shigella spp., Campylobacter jejuni, Aeromonas hydrophila, Legionella pneumophila, Vibrio cholerae, Yersinia enterocolytica and Mycobacterium avium in both influent and treated waters from the bioreactor. Total bacteria decreased during FBBR treatment. E. coli, Salmonella and Shigella spp., C. jejuni, V. cholerae, Y. enterocolytica and M. avium were not detected in aquifer water or bioreactor treated water samples. For those pathogens detected, including total coliforms, L. pneumophila and A. hydrophila, numbers were usually lower in treated water than influent samples, suggesting removal during treatment. The detection of particular bacterial species reflected their presence or absence in the influent waters. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Assessment of MTBE biodegradation in contaminated groundwater using 13C and 14C analysis: Field and laboratory microcosm studies

    International Nuclear Information System (INIS)

    Thornton, Steven F.; Bottrell, Simon H.; Spence, Keith H.; Pickup, Roger; Spence, Michael J.; Shah, Nadeem; Mallinson, Helen E.H.; Richnow, Hans H.

    2011-01-01

    Highlights: → Carbon isotope fractionation for MTBE varies with dissolved oxygen concentration. → Carbon isotope fractionation can underestimate MTBE biodegradation at plume fringes. → Fractionation factors must be for specific biodegradation mechanisms and conditions. → Specific microbial populations influence carbon isotope fractionation in groundwater. - Abstract: Radiolabelled assays and compound-specific stable isotope analysis (CSIA) were used to assess methyl tert-butyl ether (MTBE) biodegradation in an unleaded fuel plume in a UK chalk aquifer, both in the field and in laboratory microcosm experiments. The 14 C-MTBE radiorespirometry studies demonstrated widespread potential for aerobic and anaerobic MTBE biodegradation in the aquifer. However, δ 13 C compositions of MTBE in groundwater samples from the plume showed no significant 13 C enrichment that would indicate MTBE biodegradation at the field scale. Carbon isotope enrichment during MTBE biodegradation was assessed in the microcosms when dissolved O 2 was not limiting, compared with low in situ concentrations (2 mg/L) in the aquifer, and in the absence of O 2 . The microcosm experiments showed ubiquitous potential for aerobic MTBE biodegradation in the aquifer within hundreds of days. Aerobic MTBE biodegradation in the microcosms produced an enrichment of 7 per mille in the MTBE δ 13 C composition and an isotope enrichment factor (ε) of -1.53 per mille when dissolved O 2 was not limiting. However, for the low dissolved O 2 concentration of up to 2 mg/L that characterizes most of the MTBE plume fringe, aerobic MTBE biodegradation produced an enrichment of 0.5-0.7 per mille, corresponding to an ε value of -0.22 per mille to -0.24 per mille. No anaerobic MTBE biodegradation occurred under these experimental conditions. These results suggest the existence of a complex MTBE-biodegrading community in the aquifer, which may consist of different aerobic species competing for MTBE and dissolved O 2

  5. Ignition delay and soot oxidative reactivity of MTBE blended diesel fuel

    KAUST Repository

    Yang, Seung Yeon; Naser, Nimal; Chung, Suk-Ho; Al-Qurashi, Khalid

    2014-01-01

    Methyl tert-butyl ether (MTBE) was added to diesel fuel to investigate the effect on ignition delay and soot oxidative reactivity. An ignition quality tester (IQT) was used to study the ignition propensity of MTBE blended diesel fuels in a reactive spray environment. The IQT data showed that ignition delay increases linearly as the MTBE fraction increases in the fuel. A four-stroke single cylinder diesel engine was used to generate soot samples for a soot oxidation study. Soot samples were pre-treated using a tube furnace in a nitrogen environment to remove any soluble organic fractions and moisture content. Non-isothermal oxidation of soot samples was conducted using a thermogravimetric analyzer (TGA). It was observed that oxidation of 'MTBE soot' started began at a lower temperature and had higher reaction rate than 'diesel soot' across a range of temperatures. Several kinetic analyses including an isoconversional method and a combined model fitting method were carried out to evaluate kinetic parameters. The results showed that Diesel and MTBE soot samples had similar activation energy but the pre-exponential factor of MTBE soot was much higher than that of the Diesel soot. This may explain why MTBE soot was more reactive than Diesel soot. It is suggested that adding MTBE to diesel fuel is better for DPF regeneration since an MTBE blend can significantly influence the ignition characteristics and, consequently, the oxidative reactivity of soot. Copyright © 2014 SAE International.

  6. Ignition delay and soot oxidative reactivity of MTBE blended diesel fuel

    KAUST Repository

    Yang, Seung Yeon

    2014-04-01

    Methyl tert-butyl ether (MTBE) was added to diesel fuel to investigate the effect on ignition delay and soot oxidative reactivity. An ignition quality tester (IQT) was used to study the ignition propensity of MTBE blended diesel fuels in a reactive spray environment. The IQT data showed that ignition delay increases linearly as the MTBE fraction increases in the fuel. A four-stroke single cylinder diesel engine was used to generate soot samples for a soot oxidation study. Soot samples were pre-treated using a tube furnace in a nitrogen environment to remove any soluble organic fractions and moisture content. Non-isothermal oxidation of soot samples was conducted using a thermogravimetric analyzer (TGA). It was observed that oxidation of \\'MTBE soot\\' started began at a lower temperature and had higher reaction rate than \\'diesel soot\\' across a range of temperatures. Several kinetic analyses including an isoconversional method and a combined model fitting method were carried out to evaluate kinetic parameters. The results showed that Diesel and MTBE soot samples had similar activation energy but the pre-exponential factor of MTBE soot was much higher than that of the Diesel soot. This may explain why MTBE soot was more reactive than Diesel soot. It is suggested that adding MTBE to diesel fuel is better for DPF regeneration since an MTBE blend can significantly influence the ignition characteristics and, consequently, the oxidative reactivity of soot. Copyright © 2014 SAE International.

  7. Overview of technologies for removal of methyl tert-butyl ether (MTBE) from water.

    Science.gov (United States)

    Levchuk, Irina; Bhatnagar, Amit; Sillanpää, Mika

    2014-04-01

    Wide use of methyl tert-butyl ether (MTBE) as fuel oxygenates leads to worldwide environment contamination with this compound basically due to fuel leaks from storage or pipelines. Presence of MTBE in drinking water is of high environmental and social concern. Existing methods for MTBE removal from water have a number of limitations which can be possibly overcome in the future with use of emerging technologies. This work aims to provide an updated overview of recent developments in technologies for MTBE removal from water. Copyright © 2014. Published by Elsevier B.V.

  8. La spermiation chez le brochet.

    Directory of Open Access Journals (Sweden)

    DE MONTALEMBERT G.

    1980-01-01

    Full Text Available L'évolution quantitative et qualitative de la production de sperme au cours de la période de spermiation a été étudiée chez des brochets maintenus en captivité dans un étang de 400 m2. Le sperme est prélevé toutes les semaines à partir du début de février, et pendant près de 2 mois. La quantité de sperme recueillie est très faible et présente de fortes variations individuelles ; elle augmente progressivement jusqu'à la 5me semaine et décroit ensuite. La quantité moyenne de sperme récoltée par mâle est de l'ordre de 0,7 ml/semaine et varie considérablement d'un mâle à l'autre (0.07 à 1,5 ml. La concentration du sperme en spermatozoïdes varie entre 18 et 25 milliards par ml ( X = 21,5 109 + 2,11. La quantité de spermatozoïdes récoltée par semaine est de 28,5 106 + 26,4/kg de poids corporel. La qualité du sperme appréciée par l'intensité et la durée de motilité suit une évolution similaire à celle de la quantité de sperme récoltée avec des valeurs maximales à 4 semaines et minimales en début et fin de période de prélèvement. Les premières ovulations détectées sur des femelles stockées dans les mêmes conditions que les mâles ont été observées à la 6me semaine de prélèvements alors que les performances de spermiation avaient déjà fortement déclinées. Il est vraisemblable que les conditions expérimentales particulièrement traumatisantes pour les mâles ont affecté prématurément la spermiation, amplifiant ainsi le décalage fréquemment observé entre les périodes de spermiation et d'ovulation.

  9. Risk characterization of methyl tertiary butyl ether (MTBE) in tap water.

    Science.gov (United States)

    Stern, B R; Tardiff, R G

    1997-12-01

    Methyl tertiary butyl ether (MTBE) can enter surface water and groundwater through wet atmospheric deposition or as a result of fuel leaks and spills. About 30% of the U.S. population lives in areas where MTBE is in regular use. Ninety-five percent of this population is unlikely to be exposed to MTBE in tap water at concentrations exceeding 2 ppb, and most will be exposed to concentrations that are much lower and may be zero. About 5% of this population may be exposed to higher levels of MTBE in tap water, resulting from fuel tank leaks and spills into surface or groundwater used for potable water supplies. This paper describes the concentration ranges found and anticipated in surface and groundwater, and estimates the distribution of doses experienced by humans using water containing MTBE to drink, prepare food, and shower/bathe. The toxic properties (including potency) of MTBE when ingested, inhaled, and in contact with the skin are summarized. Using a range of human toxic potency values derived from animal studies, margins of exposure (MOE) associated with alternative chronic exposure scenarios are estimated to range from 1700 to 140,000. Maximum concentrations of MTBE in tap water anticipated not to cause adverse health effects are determined to range from 700 to 14,000 ppb. The results of this analysis demonstrate that no health risks are likely to be associated with chronic and subchronic human exposures to MTBE in tap water. Although some individuals may be exposed to very high concentrations of MTBE in tap water immediately following a localized spill, these exposures are likely to be brief in duration due to large-scale dilution and rapid volatilization of MTBE, the institution of emergency response and remediation measures to minimize human exposures, and the low taste and odor thresholds of MTBE which ensure that its presence in tap water is readily detected at concentrations well below the threshold for human injury.

  10. Retrofit of an MTBE-unit to ETBE

    Energy Technology Data Exchange (ETDEWEB)

    Rix, A.; Peters, U. [Degussa GmbH, Marl (Germany)

    2007-07-01

    New European policies on renewable fuels have created substantial market pressure to increase the share of bio-fuels. For blending in gasoline, ETBE formed by etherification of isobutene with bio-ethanol is an interesting alternative to direct blending of bio-ethanol. Since the physical properties of methanol and ethanol - and consequently MTBE and ETBE - are quite similar, MTBE-plants can be retrofitted for ETBE-production. Experience from a retrofit-project at Marl is presented. In an integrated C4-plant, isobutene removal is one the most important tasks of the etherification unit to purify the raffinate 2 stream for butene-1 production. Compared to MTBE, reaction rate and equilibrium constant are lower and suitable means of maintaining isobutene conversion on former levels must be found. Furthermore, the extraction of excess alcohol and its recovery by distillation is more difficult. The ethanol-water azeotrope formed on top of the alcohol recovery column has to undergo a further drying process. Alternatives for ethanol drying have been evaluated and performance data for a membrane process is presented. (orig.)

  11. BTEX and MTBE adsorption onto raw and thermally modified diatomite.

    Science.gov (United States)

    Aivalioti, Maria; Vamvasakis, Ioannis; Gidarakos, Evangelos

    2010-06-15

    The removal of BTEX (benzene, toluene, ethyl-benzene and xylenes) and MTBE (methyl tertiary butyl ether) from aqueous solution by raw (D(R)) and thermally modified diatomite at 550, 750 and 950 degrees C (D(550), D(750) and D(950) respectively) was studied. Physical characteristics of both raw and modified diatomite such as specific surface, pore volume distribution, porosity and pH(solution) were determined, indicating important structural changes in the modified diatomite, due to exposure to high temperatures. Both adsorption kinetic and isotherm experiments were carried out. The kinetics data proved a closer fit to the pseudo-second order model. Maximum values for the rate constant, k(2), were obtained for MTBE and benzene (48.9326 and 18.0996 g mg(-1)h(-1), respectively) in sample D(550). The isotherm data proved to fit the Freundlich model more closely, which produced values of the isotherm constant 1/n higher than one, indicating unfavorable adsorption. The highest adsorption capacity, calculated through the values of the isotherm constant k(F), was obtained for MTBE (48.42 mg kg(-1) (mg/L)(n)) in sample D(950). Copyright 2010 Elsevier B.V. All rights reserved.

  12. Water quality and MTBE water pollution; Evidenze di presenza di MTBE sulle acque sotterranee di aree a rischio

    Energy Technology Data Exchange (ETDEWEB)

    Buiatti, M.; Mascini, M.; Monanni, R. [Florence Univ., Florence (Italy). Centro Interdipartimentale Biotecnologie Agrarie Chimiche Industriali; Agati, L.; Bartoli, C.; Bolletti, P.; Cortonesi, B.; Martinelli, L. [Agenzia Regionale per la Protezione dell' Ambiente della Toscana, Florence (Italy); Filipponi, M.; Piangoloni, A. [Nuove Acque SpA,, Arezzo (Italy); Mancini, G. [Autorita' di ambito territoriale ottimale n.4, Arezzo (Italy)

    2001-11-01

    The research project, here presented, was defined with the aim of evaluating the eventual presence of MTBE and the possible relative impact in water destined to human use; the territorial valence of the project was extended to the competence region n. 4 of the Tuscany water authority (AATO n. 4). University of Florence, ARPAT, AATO n. 4 and Nuove Acque SpA, in this role of manager for the integrated water cycle in the country, have productively contributed to the project. [Italian] La Nuove Acque SpA, soggetto gestore del ciclo idrico integrato, l'Universita' degli Studi di Firenze, l'Agenzia Regionale per la Protezione Ambientale e l'Autorita' di Ambito Territoriale hanno realizzato un progetto di verifica e messa a punto delle metodologie analitiche per il monitoraggio delle eventuali presenze di MTBE nelle acque, con particolare riferimento agli acquiferi sotterranei.

  13. Long term studies on the anaerobic biodegradability of MTBE and other gasoline ethers

    DEFF Research Database (Denmark)

    Waul, Christopher Kevin; Arvin, Erik; Schmidt, Jens Ejbye

    2009-01-01

    to investigate the anaerobic biodegradability of MTBE and other gasoline ethers. Inoculums collected from various environments were used, along with different electron acceptors. Only one set of the batch experiments showed a 30-60% conversion of MTBE to tert-butyl alcohol under Fe(III)-reducing conditions...

  14. Model description and kinetic parameter analysis of MTBE biodegradation in a packed bed reactor

    DEFF Research Database (Denmark)

    Waul, Christopher Kevin; Arvin, Erik; Schmidt, Jens Ejbye

    2008-01-01

    A dynamic modeling approach was used to estimate in-situ model parameters, which describe the degradation of methyl tert-butyl ether (MTBE) in a laboratory packed bed reactor. The measured dynamic response of MTBE pulses injected at the reactor's inlet was analyzed by least squares and parameter...

  15. MICROBIAL ANALYSIS OF MTBE, BTEX BIOREMEDIATION: BIONETS CONTAINING PM1, SOS, ISOLITE.

    Science.gov (United States)

    MTBE and BTEX (benzene, toluene, ethylbenzene, and xylene) are major problems of many sites in the United States. The objective of this study was to determine if biologically active in-situ BioNets could bioremediation MTBE and BTEX contaminated groundwater. Seven BioNets were ...

  16. BTEX AND MTBE BIOREMEDIATION: BIONETS™ CONTAINING SOS, PM1 AND ISOLITE®

    Science.gov (United States)

    MTBE and BTEX (benzene, toluene, ethylbenzene, and xylenes) are major problems of many sites in the United States. The objective of this study was to determine if biologically active in situ BioNets could bioremediate MTBE and BTEX contaminated groundwater. Seven BioNets w...

  17. MICROBIAL ANALYSIS OF MTBE, BTEX BIOREMEDIATION: BIONETS(TM) CONTAINING PM1, SOS, ISOLITE (R)

    Science.gov (United States)

    MTBE and BTEX (benzene, toluene, ethylbenzene, and xylene) are major problems of many sites in the United States. The objective of this study was to determine if biologically active in-situ BioNets could bioremediation MTBE and BTEX contaminated groundwater. Seven BioNets were ...

  18. MICROBIAL ANALYSIS OF MTBE, BTEX BIOREMEDIATION: BIONETS CONTAINING PM1, SOS, ISOLITE�

    Science.gov (United States)

    MTBE and BTEX (benzene, toluene, ethylbenzene, and xylene) are major problems of many sites in the United States. The objective of this study was to determine if biologically active in-situ BioNets could bioremediate MTBE and BTEX contaminated groundwater. Seven BioNets were plac...

  19. EFFECT OF BTEX ON THE DEGRADATION OF MTBE AND TBA BY MIXED BACTERIAL CONSORTIUM

    Science.gov (United States)

    Methyl tert-butyl ether (MTBE) contamination in groundwater often coexists with benzene, toluene, ethylbenzene, and xylene (BTEX) near the source of the plume. Tertiary butyl alcohol (TBA) is a prevalent intermediate of MTBE degradation. Therefore, there is a significant p...

  20. REMEDIATION OF MTBE FROM DRINKING WATER: AIR STRIPPING FOLLOWED BY OFF-GAS ADSORPTION

    Science.gov (United States)

    The widespread use of methyl tertiary butyl ether (MTBE) as an oxygenate in gasoline has resulted in the contamination of a large number of ground and surface water sources. Even though air stripping has been proven to be an effective treatment technology for MTBE removal, off-ga...

  1. AIR STRIPPING AND OFF-GAS ADSORPTION FOR THE REMOVAL OF MTBE FROM DRINKING WATER

    Science.gov (United States)

    Methyl-tertiary butyl ether (MTBE) is a synthetic organic chemical, primarily used for oxgenating fuel. The 1990 Federal Clean Air Act Amendments mandated the use of fuel oxgenates in areas where air quality did not meet national standards, which led to widespread use of MTBE in...

  2. Risicogrenzen voor MTBE (Methyl tertiair-Butyl Ether) in bodem, sediment, grondwater, oppervlaktewater en voor drinkwaterbereiding

    NARCIS (Netherlands)

    Swartjes FA; Baars AJ; Fleuren RHLJ; Otte PF; LER

    2004-01-01

    Recentelijk is politieke commotie ontstaan ten gevolge van de mogelijke schadelijke gezondheidseffecten van Methyl tertiair-Butyl Ether (MTBE). Dit was reden voor het ministerie van VROM om het RIVM te verzoeken risicogrenzen voor MTBE in bodem, sediment, grondwater, oppervlaktewater, drinkwater en

  3. CONTROLLED, SHORT-TERM DERMAL AND INHALATION EXPOSURE TO MTBE AND DIBROMOCHLOROMETHANE

    Science.gov (United States)

    The oxygenate methyl tert-butyl ether (MTBE) has been added to gasoline to meet national ambient air quality standards in those parts of the US that are non-compliant for carbon monoxide. Although MTBE has provided important health benefits in terms of reduced hazardous air po...

  4. INHALATION EXPOSURE TO METHYL TERT-BUTYL ETHER (MTBE) AND DIBROMOCHLOROMETHANE (DBCM) USING CONTINUOUS BREATH ANALYSIS

    Science.gov (United States)

    The oxygenate methyl tert-butyl ether (MTBE) has been added to gasoline to help meet national ambient air quality standards in those parts of the U.S. that are non-compliant for carbon monoxide. Although MTBE has provided important health benefits in terms of reduced haza...

  5. Persulfate Oxidation of MTBE- and Chloroform-Spent Granular Activated Carbon

    Science.gov (United States)

    Activated persulfate (Na2S2O8) regeneration of methyl tert-butyl ether (MTBE) and chloroform-spent GAC was evaluated in this study. Thermal-activation of persulfate was effective and resulted in greater MTBE removal than either alkaline-activation or H2O2–persulfate binary mixtur...

  6. USE OF MEMBRANE BIOREACTOR FOR BIODEGRADATION OF MTBE IN CONTAMINATED WATER1

    Science.gov (United States)

    An ultrafiltration membrane bioreactor was evaluated for biodegradation of methyl tert-butyl ether (MTBE) in contaminated water. The system was fed 5 mg/L MTBE in granular activated carbon (GAC) treated Cincinnati tap water containing ample buffer and nutrients. Within 120...

  7. Used motor oil as a source of MTBE, TAME, and BTEX to ground water

    Science.gov (United States)

    Baker, R.J.; Best, E.W.; Baehr, A.L.

    2002-01-01

    Methyl tert-butyl ether (MTBE), the widely used gasoline oxygenate, has been identified as a common ground water contaminant, and BTEX compounds (benzene, toluene, ethylbenzene, and xylenes) have long been associated with gasoline spills. Because not all instances of ground water contamination by MTBE and BTEX can be attributed to spills or leaking storage tanks, other potential sources need to be considered. In this study, used motor oil was investigated as a potential source of these contaminants. MTBE in oil was measured directly by methanol extraction and gas chromatography using a flame ionization detector (GC/FID). Water was equilibrated with oil samples and analyzed for MTBE, BTEX, and the oxygenate tert-amyl methyl ether (TAME) by purge-and-trap concentration followed by GC/FID analysis. Raoult's law was used to calculate oil-phase concentrations of MTBE, BTEX, and TAME from aqueous-phase concentrations. MTBE, TAME, and BTEX were not detected in any of five new motor oil samples, whereas these compounds were found at significant concentrations in all six samples of the used motor oil tested for MTBE and all four samples tested for TAME and BTEX. MTBE concentrations in used motor oil were on the order of 100 mg/L. TAME concentrations ranged from 2.2 to 87 mg/L. Concentrations of benzene were 29 to 66 mg/L, but those of other BTEX compounds were higher, typically 500 to 2000 mg/L.

  8. Iron Amendment and Fenton Oxidation of MTBE-Spent Granular Activated Carbon

    Science.gov (United States)

    Fenton-driven regeneration of Methyl tert-butyl ether (MTBE)-spent granular activated carbon (GAC) involves Fe amendment to the GAC to catalyze H2O2 reactions and to enhance the rate of MTBE oxidation and GAC regeneration. Four forms of iron (ferric sulfate, ferric chloride, fer...

  9. Fenton-Driven Chemical Regeneration of MTBE-Spent Granular Activated Carbon -- A Pilot Study

    Science.gov (United States)

    MTBE-spent granular activated carbon (GAC) underwent 3 adsorption/oxidation cycles. Pilot-scale columns were intermittently placed on-line at a ground water pump and treat facility, saturated with MTBE, and regenerated with H2O2 under different chemical, physical, and operational...

  10. Fenton-like Degradation of MTBE: Effects of Iron Counter Anion and Radical Scavengers

    Science.gov (United States)

    Fenton-driven oxidation of Methyl tert-butyl ether (MTBE) (0.11-0.16 mM) in batch reactors containing ferric iron (5 mM), hydrogen peroxide (H2O2) (6 mM) (pH=3) was performed to investigate MTBE transformation mechanisms. Independent variables included the form of iron (Fe) (Fe2(...

  11. Trieb et énergie chez Herder

    OpenAIRE

    Pénisson, Pierre

    2011-01-01

    Herder s’inspire à la fois de la philosophie leibnizienne de la force, de la théorie d’Albrecht von Haller sur l’excitabilité (Reizbarkeit) et des pensées françaises de l’énergie, que l’on trouve aussi chez Sulzer à Berlin et James Harris en Angleterre, et d’une autre façon chez Hamann que commentera Hegel. Mais le Trieb est plus qu’une concentration de force, et la critique herdérienne des pensées françaises de l’énergie ou du culte allemand du génie retrouve les arguments du premier discour...

  12. Detections of MTBE in surficial and bedrock aquifers in New England

    International Nuclear Information System (INIS)

    Grady, S.J.

    1995-01-01

    The gasoline additive methyl tert-butyl ether (MTBE) was detected in 24% of water samples collected from surficial and bedrock aquifers in areas of New England. MTBE was the most frequently detected volatile organic compound among the 60 volatile chemicals analyzed and was present in 33 of 133 wells sampled from July 1993 through September 1995. The median MTBE concentration measured in ground-water samples was 0.45 microgram per liter and concentrations ranged from 0.2 to 5.8 microgram per liter. The network of wells sampled for MTBE consisted of 103 monitoring wells screened in surficial sand-and-gravel aquifers and 30 domestic-supply wells in fractured crystalline bedrock aquifers. Seventy-seven percent of all MTBE detections were from 26 shallow monitoring wells screened in surficial aquifers. MTBE was detected in42% of monitoring wells in urban areas. In agricultural areas, MTBE was detected i 8% (2 of 24) of wells and was not detected in undeveloped areas. Sixty-two percent of the MTBE detections in surficial aquifers were from wells within 0.25 mile of gasoline stations or underground gasoline storage tanks; all but one of these wells were in Connecticut and Massachusetts, where reformulated gasoline is used. MTBE was detected in 23% of deep domestic-supply wells that tapped fractured bedrock aquifers. MTBE was detected in bedrock wells only in Connecticut and Massachusetts; land use near the wells was suburban to rural, and none of the sampled bedrock wells were within 0.25 mile of a gasoline station

  13. The chances for green petrol. Alternative for MTBE is ethylene tertiary butylether; Kans op groenere benzine stijgt. Alternatief voor MTBE is etheen tertiair butyl ether

    Energy Technology Data Exchange (ETDEWEB)

    Van de Graaf, A.; Steentjes, A. [eds.

    2000-05-03

    To find a useful and environment-friendly fuel is difficult. Lead and benzene already were replaced by methyl tertiary butylether (MTBE), but this fuel additive too appears to be hazardous for man and the environment. When MTBE will be banned the chances for so-called green petrol (made from biomass) are rising. A brief overview of the developments in the field of fuel additives so far is given.

  14. Effects of MTBE blended diesel fuel on diesel combustion and emissions; MTBE kongo keiyu ga diesel nensho haiki ni oyobosu eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Shundo, S; Yokota, H; Kakegawa, T [Hino Motors, Ltd., Tokyo (Japan)

    1997-10-01

    The effects of MTBE (Methyl-t-butyl ether) blended diesel fuel on diesel combustion and emissions were studied. In conventional diesel combustion, the testing mode was carried out in conformity with the Japanese 13 mode. Furthermore, this fuel was applied to a new combustion system (Homogeneous Charge Intelligent Multiple Injection). MTBE blended diesel fuel is more effective in the case of new combustion system and very low NOx, PM capability is suggested. 6 refs., 6 figs., 2 tabs.

  15. In vitro susceptibility of Mycobacterium tuberculosis, Mycobacterium africanum, Mycobacterium bovis, Mycobacterium avium, Mycobacterium fortuitum, and Mycobacterium chelonae to ticarcillin in combination with clavulanic acid.

    OpenAIRE

    Casal, M J; Rodriguez, F C; Luna, M D; Benavente, M C

    1987-01-01

    The in vitro susceptibility of Mycobacterium tuberculosis, Mycobacterium bovis, Mycobacterium africanum, Mycobacterium avium, Mycobacterium fortuitum, and Mycobacterium chelonae (M. chelonei) to ticarcillin in combination with calvulanic acid (CA) was studied by the agar dilution method. All the M. tuberculosis, M. bovis, and M. africanum strains were inhibited at a ticarcillin concentration of 32 micrograms/ml or lower in combination with 5 micrograms of CA. M. chelonae and M. avium strains ...

  16. The Mycobacterium tuberculosis homologue of the Mycobacterium ...

    African Journals Online (AJOL)

    With the completion of genome sequencing of Mycobacterium tuberculosis and upsurge in the incidence of M. tuberculosis infection worldwide partly as a result of HIV pandemic, there is need for rationale approach to vaccine and chemotherapy discoveries for M. tuberculosis. The homologue of mig gene of. Mycobacterium ...

  17. MTBE, the evolution of a commodity and its impact on US butanes

    International Nuclear Information System (INIS)

    Whitley, S.C.

    1994-01-01

    Since 1990, members of the gas processing and natural gas liquids communities have watched with eager anticipation the growth and development of methyl tertiary butyl ether. MTBE, as it is more commonly known, is a motor fuel oxygenate and octane enhancer. Not too long ago there were several butane-based MTBE plants in the engineering or construction phase and many more were on the drawing board. At one time the demand outlook for butanes that could potentially be consumed by existing and planned butane-based MTBE facilities exceeded 150,000 b/d. That outlook has been downgraded substantially over the past two years as technical and economic factors forced several companies to scrap their plans for worldscale butane-based MTBE plants. A look at the evolution of MTBE as a commodity may explain what has happened, and why demand for butanes by this market sector is no longer as promising as it was only two short years ago. This paper reviews first the impact that government regulations and legislation played in creating the need for MTBE. This will be followed by a discussion of how subsequent proposals and legislation have led to downward revisions in the US outlook for MTBE and butanes

  18. Enhancement of the Biodegradability of Methyl tert- Butyl Ether (MTBE by Advanced Oxidation

    Directory of Open Access Journals (Sweden)

    Mehraban Sadeghi

    2006-06-01

    Full Text Available The effectiveness of ozone treatment for improving the biodegradability of recalcitrant pollutants has been proved by investigating the ozonation reaction of Methyl tert-Butyl Ether (MTBE as a bioresistant gasoline oxygenate. Laboratory scale experiments have been carried out at room temperature by bubbling for 120 minutes ozonated air (3.4 ppm/min into 3 liter of an alkaline (pH=11.5 aqueous solution (100 mg/L of MTBE. The experimental results indicated that during the ozonation, complete MTBE degradation occurs in 100 minutes and after this time, ozone consumption goes on very slowly. At the end of the ozonation, after 100 minutes, the initial value of COD (256 mg O2/L is 98 and corresponds to a relative removal of about 62%. As for MTBE solution biodegradability expressed as (BOD5 / (COD ratio, during the first 90 minutes, its value regularly increases from lowest 0.01 up to a maximum of 0.68 that corresponds to an ozone consumption of 1.25 mg per each mg of COD initially present in the solution. The research showed that partial degradation of MTBE in the advanced oxidation processes results an increase in its biological degradation. But more oxidation results lower  (BOD5 / (COD ratio. Also the research showed that for idealization of the chemical oxidation conditions of MTBE, it needs to decrease COD to 46-68% before the biological degradation. The experimental results for determining the rate of MTBE removal due to stripping showed that about 14% of MTBE strips out after an hour of sparging with oxygen gas. The fraction of MTBE oxidized and/or striped increases to about 28% (in pH=7 and 70% (in pH=11.5 with ozonation over the same time period.

  19. Quantifying MTBE biodegradation in the Vandenberg Air Force Base ethanol release study using stable carbon isotopes

    Science.gov (United States)

    McKelvie, Jennifer R.; Mackay, Douglas M.; de Sieyes, Nicholas R.; Lacrampe-Couloume, Georges; Sherwood Lollar, Barbara

    2007-12-01

    Compound-specific isotope analysis (CSIA) was used to assess biodegradation of MTBE and TBA during an ethanol release study at Vandenberg Air Force Base. Two continuous side-by-side field releases were conducted within a preexisting MTBE plume to form two lanes. The first involved the continuous injection of site groundwater amended with benzene, toluene and o-xylene ("No ethanol lane"), while the other involved the continuous injection of site groundwater amended with benzene, toluene and o-xylene and ethanol ("With ethanol lane"). The δ 13C of MTBE for all wells in the "No ethanol lane" remained constant during the experiment with a mean value of - 31.3 ± 0.5‰ ( n = 40), suggesting the absence of any substantial MTBE biodegradation in this lane. In contrast, substantial enrichment in 13C of MTBE by 40.6‰, was measured in the "With ethanol lane", consistent with the effects of biodegradation. A substantial amount of TBA (up to 1200 μg/L) was produced by the biodegradation of MTBE in the "With ethanol lane". The mean value of δ 13C for TBA in groundwater samples in the "With ethanol lane" was - 26.0 ± 1.0‰ ( n = 32). Uniform δ 13C TBA values through space and time in this lane suggest that substantial anaerobic biodegradation of TBA did not occur during the experiment. Using the reported range in isotopic enrichment factors for MTBE of - 9.2‰ to - 15.6‰, and values of δ 13C of MTBE in groundwater samples, MTBE first-order biodegradation rates in the "With ethanol lane" were 12.0 to 20.3 year - 1 ( n = 18). The isotope-derived rate constants are in good agreement with the previously published rate constant of 16.8 year - 1 calculated using contaminant mass-discharge for the "With ethanol lane".

  20. Anaerobic degradation of methyl tert-butyl ether (MTBE) and tert-butyl alcohol (TBA).

    Science.gov (United States)

    Finneran, K T; Lovley, D R

    2001-05-01

    The potential for anaerobic degradation of methyl tert-butyl ether (MTBE) and tert-butyl alcohol (TBA) was investigated in laboratory incubations of sediments from a petroleum-contaminated aquifer and in aquatic sediments. The addition of humic substances (HS) stimulated the anaerobic degradation of MTBE in aquifer sediments in which Fe(III) was available as an electron acceptor. This is attributed to the fact that HS and other extracellular quinones can stimulate the activity of Fe(III)-reducing microorganisms by acting as an electron shuttle between Fe(III)-reducing microorganisms and insoluble Fe(III) oxides. MTBE was not degraded in aquifer sediments without Fe(III) and HS. [14C]-MTBE added to aquatic sediments adapted for anaerobic MTBE degradation was converted to 14CO2 in the presence or absence of HS or the HS analog, anthraquione-2,6-disulfonate. Unamended aquatic sediments produced 14CH4 as well as 14CO2 from [14C]-MTBE. The aquatic sediments also rapidly consumed TBA under anaerobic conditions and converted [14C]-TBA to 14CH4 and 14CO2. An adaptation period of ca. 250-300 days was required prior to the most rapid anaerobic MTBE degradation in both sediment types, whereas TBA was metabolized in the aquatic sediments without a lag. These results demonstrate that, under the appropriate conditions, MTBE and TBA can be degraded in the absence of oxygen. This suggests that it may be possible to design strategies for the anaerobic remediation of MTBE in petroleum-contaminated subsurface environments.

  1. Photovaporisation prostatique au laser chez les patients à haut ...

    African Journals Online (AJOL)

    infection urinaire chez 5 patients (10.6%), une dysurie chez 4 patients et une hémorragie retardée chez 4 autres (8.5%). Un seul de ces patients a nécessité une transfusion sanguine et aucun patient n'a nécessité une réintervention. En 3 mois de suivi un seul patient a nécessité une incision du col vésical pour sclérose du ...

  2. ESTCP Cost and Performance Report. In-Situ Bioremediation of MTBE in Ground Water

    National Research Council Canada - National Science Library

    Miller, Karen

    2003-01-01

    ... (methyl-tert-butyl-ether) and other dissolved gasoline components. It was implemented at the Naval Base Ventura County, Port Hueneme, CA to prevent further contamination of ground water by MTBE leaching from gasoline contaminated soils...

  3. A Practical Approach to the Design, Monitoring, and Optimization of the Situ MTBE Aerobic Biobarriers

    National Research Council Canada - National Science Library

    Johnson, Paul

    2004-01-01

    ...) aerobic biobarriers. The technology discussed in this document is applied for the purposes of containing or preventing further migration of existing dissolved MTBE groundwater plumes, or for the purpose of eliminating...

  4. Adduction of DNA with MTBE and TBA in mice studied by accelerator mass spectrometry.

    Science.gov (United States)

    Yuan, Y; Wang, H F; Sun, H F; Du, H F; Xu, L H; Liu, Y F; Ding, X F; Fu, D P; Liu, K X

    2007-12-01

    Methyl tert-butyl ether (MTBE) is a currently worldwide used octane enhancer substituting for lead alkyls and gasoline oxygenate. Our previous study using doubly (14)C-labeled MTBE [(CH(3))(3) (14)CO(14)CH(3)] has shown that MTBE binds DNA to form DNA adducts at low dose levels in mice. To elucidate the mechanism of the binding reaction, in this study, the DNA adducts with singly (14)C-labeled MTBE, which was synthesized from (14)C-methanol and tert-butyl alcohol (TBA), or (14)C-labeled TBA in mice have been measured by ultra sensitive accelerator mass spectrometry. The results show that the methyl group of MTBE and tert-butyl alcohol definitely form adducts with DNA in mouse liver, lung, and kidney. The methyl group of MTBE is the predominant binding part in liver, while the methyl group and the tert-butyl group give comparable contributions to the adduct formation in lung and kidney.

  5. Comparative effects of MTBE and ethanol additions into gasoline on exhaust emissions

    Science.gov (United States)

    Song, Chong-Lin; Zhang, Wen-Mei; Pei, Yi-Qiang; Fan, Guo-Liang; Xu, Guan-Peng

    The effects of the additives of ethanol (EA) and methyl tert-butyl ether (MTBE) in various blend ratios into the gasoline fuel on the exhaust emissions and the catalytic conversion efficiencies were investigated in an EFI gasoline engine. The regulated exhaust emissions (CO, THC and NO X) and the unregulated exhaust emissions (benzene, formaldehyde, acetaldehyde, unburned EA and MTBE) before and after the three-way catalytic converter were measured. The experimental results showed that EA brought about generally lower regulated engine-out emissions than MTBE did. But, the comparison of the unregulated engine-out emissions between both additives was different. Concretely, the effect of EA on benzene emission was worse than that of MTBE on the whole, which was a contrast with formaldehyde emission. The difference in the acetaldehyde comparison depended much on the engine operating conditions, especially the engine speed. Both EA and MTBE were identified in the engine exhaust gases only when they were added to the fuel, and their volume fraction increased with blend ratios. The catalytic conversion efficiencies of the regulated emissions for the EA blends were in general lower than those for MTBE blends, especially at the low and high engine speeds. There was little difference in the catalytic conversion efficiencies for both benzene and formaldehyde, while distinct difference for acetaldehyde.

  6. Ecriture traumatique de la problematique de la jeunesse chez deux ...

    African Journals Online (AJOL)

    Ecriture traumatique de la problematique de la jeunesse chez deux romanciers africains froncophones: Ahmadou kourouma et boubacar boris diop, ou l'Afrique au pied du mur de la crise de la conscience Africaine.

  7. Tuberculose lymphonodale cervicale chez les enfants vaccines par ...

    African Journals Online (AJOL)

    La tuberculose ganglionnaire cervicale est une localisation extrapulmonaire relativement fréquente chez l'enfant. Elle pose essentiellement des difficultés de prévention. L'objectif de ce travail est d'étudier les particularités diagnostiques et thérapeutiques chez des enfants vaccinés par le BCG. Matériel et méthodes: Nôtre ...

  8. Les dyslipidemies et antiretroviraux chez les personnes vivant avec ...

    African Journals Online (AJOL)

    hypercholestérolémie, l'hyper LDL-cholestérolémie, l'hypo HDLcholestérolémie ont été retrouvées respectivement chez 41,4%, 23,5% et 17,4% des patients. La différence n'est pas significative entre les fréquences des troubles lipidiques chez les ...

  9. Aspects des Onychomycoses chez des patients camerounais de ...

    African Journals Online (AJOL)

    ... biologiques et évolutifs des onychomycoses chez des patients camerounais. Méthode : Il s'agit d'une étude rétrospective et descriptive menée de mars 2011 à mars 2014 dans l'unité de dermatologie de l'hôpital général de Douala (HGD), incluant des patients chez lesquels le diagnostic d'onychomycose avait été posé.

  10. MTBE and aromatic hydrocarbons in North Carolina stormwater runoff.

    Science.gov (United States)

    Borden, Robert C; Black, David C; McBlief, Kathleen V

    2002-01-01

    A total of 249 stormwater samples were collected from 46 different sampling locations in North Carolina over an approximate 1-year period and analyzed to identify land use types where fuel oxygenates and aromatic hydrocarbons may be present in higher concentrations and at greater frequency. Samples were analyzed by gas chromatography-mass spectrometry in ion selective mode to achieve a quantitation limit of 0.05 microg/l. m-,p-Xylene and toluene were detected in over half of all samples analyzed, followed by MTBE: o-xylene: 1,3,5-trimethylbenzene: ethylbenzene; and 1,2,4-trimethylbenzene. Benzene, DIPE, TAME and 1,2,3-trimethylbenzene were detected in runoff from a gas station or discharge of contaminated groundwater from a former leaking underground storage tank. For all of the aromatic hydrocarbons, the maximum observed contaminant concentrations were over an order of magnitude lower than current drinking water standards.

  11. The role of mesopores in MTBE removal with granular activated carbon.

    Science.gov (United States)

    Redding, Adam M; Cannon, Fred S

    2014-06-01

    This activated carbon research appraised how pore size and empty-bed contact time influenced the removal of methyl tert-butyl ether (MTBE) at part-per-billion (ppb) concentrations when MTBE was the sole organic impurity. The study compared six granular activated carbons (GACs) from three parent sources; these GACs contained a range of pore volume distributions and had uniform slurry pHs of 9.7-10.4 (i.e. the carbons' bulk surface chemistries were basic). Several of these activated carbons had been specifically tailored for enhanced sorption of trace organic compounds. In these tests, MTBE was spiked into deionized-distilled water (∼pH 7); MTBE loading was measured by isotherms and by rapid small-scale column tests (RSSCTs) that simulated full-scale empty-bed contact times of 7, 14, and 28 min. The results showed that both ultra-fine micropores and small-diameter mesopores were important for MTBE adsorption. Specifically, full MTBE loading during RSSCTs bore a strong correlation (R(2) = 0.94) to the product (mL/g × mL/g) of pore volume ≤4.06 Å wide and pore volume between ∼22 Å and ∼59 Å wide. This correlation was greater than for the product of any other pore volume combinations. Also, this product exhibited a stronger correlation than for just one or the other of these two pore ranges. This multiplicative relationship implied that both of these pore sizes were important for the optimum GAC performance of these six carbons (i.e. favorable mass transfer coupled with favorable sorption). The authors also compared MTBE mass loading during RSSCTs (μg MTBE/g GAC) to isotherm capacity (μg MTBE/g GAC). This RSSCT loading "efficiency" ranged from 28% to 96% for the six GACs; this efficiency correlated most strongly to pores that were 14-200 Å wide (R(2) = 0.94). This correlation indicated that only those carbons with a sufficient volume of 14-200 Å pores could adsorb MTBE to the extent that would be predicted from isotherm data. Copyright

  12. Remediation challenges posed by the fate and transport properties of MTBE

    International Nuclear Information System (INIS)

    Day, M.J.

    2002-01-01

    Releases of fuel from underground tank systems have been a major source of groundwater contamination for several decades. The fate and transport characteristics of fuel components significantly influence the potential risk to groundwater supplies and the methodologies to manage and remediate contamination at fuel release sites. The recognition that MTBE can be more mobile in groundwater systems than other components of oxygenated fuels has put an increased emphasis on early detection and response to fuel leaks and spills. Remediation of oxygenated fuel releases usually follows a sequence of tasks: receptor protection, source control, residual and dissolved phase remediation, and monitored natural attenuation. Good characterization of hydrogeological and geochemical conditions is required because understanding the fate and transport of fuel components is critical to developing an appropriate management plan and an efficient remediation program. Understanding the specific site conditions allows appropriate selection and sequencing of remedial technologies. The physical and chemical characteristics of MTBE can result in a higher mobility in the subsurface, compared with the BTEX components of a gasoline release. These same characteristics make MTBE more readily extractable from the subsurface compared with BTEX. There is an impression that remediating gasoline releases containing MTBE requires costly, specialized technologies compared with those employed to deal with non-oxygenated fuel releases. However, the characteristics of MTBE are well suited to traditional, physical remedial approaches that have proven to be effective with the other components of gasoline. Technologies such as groundwater extraction, soil vapor extraction (SVE), and thermal desorption work exceptionally well with MTBE due to its low adsorptive and high vapor pressure characteristics. Similarly, recent studies have demonstrated that MTBE is biodegradable under a wide variety of conditions

  13. Bio-MTBE. A new option to fulfil biofuel quota for gasoline; Bio-MTBE. Eine neue Option zur Erfuellung der Biokraftstoffquote in Ottokraftstoffen

    Energy Technology Data Exchange (ETDEWEB)

    Busch, Oliver M.; Schade, Arnd; Locher, Annette [Evonik Industries AG, Essen (Germany)

    2013-05-15

    To meet the legally required bio-fuel quota in gasoline, an alternative to the ethanol blend E10 is nowavailable for nearly one year. Evonik Industries has introduced a bio-version of methyl tert-butyl ether (MTBE), an anti-knock agent, on the market. Chemically, both products are identical, because in production methanol is exchanged for bio-methanol. Bio-methanol is produced from raw glycerine, which arises as a byproduct from biodiesel production. This makes bio-MTBE an ideal bio-fuel component as defined by the EU's Renewable Energy Directive: Fuel components made from waste and residues are ''double counted'' regarding their bio-energy content. The product is widely used in the German and Dutch markets. In both countries, bio- MTBE is legally recognized as a bio-fuel component fulfilling double counting requirements. In the meantime, also other European countries have been introducing double counting for second-generation biofuel components. The EU Commission proposed to allow components based on residual materials to be calculated fourfold in the future. Should this be the case, bio-MTBE would become significantly more valuable. (orig.)

  14. Measurement of critical temperatures and critical pressures for binary mixtures of methyl tert-butyl ether (MTBE) + alcohol and MTBE + alkane

    International Nuclear Information System (INIS)

    Han, Kewei; Xia, Shuqian; Ma, Peisheng; Yan, Fangyou; Liu, Tao

    2013-01-01

    Highlights: • The critical properties of seven binary mixtures related to gasoline were measured. • The critical properties of the five systems containing MTBE were reported for the first time. • Binary interaction parameters were fitted by experimental data using PR EOS with Wong–Sandler mixing rule. • Redlich–Kister equation was used to correlate the experimental data. -- Abstract: A set of high-pressure view apparatus was designed for determining the critical properties of chemicals. In order to check the reliability of the apparatus, the critical temperatures (T c ) and critical pressures (P c ) of pure n-heptane, cyclohexane, methanol, ethanol, 1-propanol, methyl tert-butyl ether (MTBE), and binary mixture n-hexane + ethanol were measured. The experimental data were in good agreement with the literature data, which proves the reliability of the apparatus used in the work. The critical temperatures and critical pressures of five binary mixtures containing gasoline additive (MTBE + n-heptane, MTBE + cyclohexane, MTBE + methanol, MTBE + ethanol, MTBE + 1-propanol) were measured using the high-pressure view cell with visual observation. The critical temperatures and critical pressures for the five binary mixtures were all reported for the first time. In addition, the critical temperatures and critical pressures of the binary mixture n-heptane + cyclohexane (two of main components in gasoline) were also measured. All the critical lines for the mixtures studied are continuous which connect the critical points of the two pure components, indicating their phase diagrams belong to type I proposed by Scott and van Konynenburg. The critical points of these systems were calculated by the Peng–Robinson equation of state with the Wong–Sandler mixing rule. This model could calculate the critical properties of the mixtures well with the binary interaction parameter k ij obtained by fitting the experimental critical data. And the experimental data were all

  15. MTBE IN SITU BIODEGRADATION IN BIONETS USING ISOLITE, PM1, SLOW RELEASING OXYGEN AND AIR IN INDIAN COUNTRY

    Science.gov (United States)

    Methyl tert-Butyl Ether (MTBE), a gasoline additive, is a persistent, foul tasting chemical and more mobile in ground water than BTEX. Our objective was to determine if biologically active in situ Bionets could bioremediate MTBE. Seven Bionets, most containing 3 fractures each,...

  16. Biodegradation of methyl tertiary butyl ether (MTBE) using a granular activated carbon trickling filter

    Energy Technology Data Exchange (ETDEWEB)

    Converse, B.M.; Schroeder, E.D.; Chang, D.P.Y.

    1999-07-01

    A pilot scale trickling filter was constructed using granular activated carbon (GAC) as the packing medium and inoculated with a microbial culture known to degrade MTBE. The packing dimensions were 0.076 m in diameter and 0.22 m deep. The unit operated with recycling flow for two months before a biofilm was observed on the GAC. After two additional months the biofilm had visibly spread throughout the packing. A few pieces of GAC were placed in a sealed bottle with MTBE-contaminated water and nutrients. Headspace analysis performed over 14 days confirmed that MTBE degradation was occurring. The trickling filter was converted to continuous flow and operated for one month at a nominal flow rate of 0.1 L/min and a hydraulic loading rate of 32 m{sup 3}/m{sup 2}-d. Samples were collected for analysis at the spray nozzle and at the bottom of the trickling filter. Fractional removal varied with influent MTBE concentration, temperature and liquid flow rate. Percent MTBE removal was as high as 85%. A mechanical failure resulted in the trickling filter bed drying and percent removal dropping to less than 1 percent. However, the system recovered within five days.

  17. Trends in the occurrence of MTBE in drinking water in the Northeast United States

    Science.gov (United States)

    Moran, M.J.

    2007-01-01

    Public water systems in Connecticut, Maine, Maryland, New Hampshire, New Jersey, and Rhode Island sampled treated drinking water from 1993-2006 and analyzed the samples for MTBE. The US Geological Survey examined trends in the occurrence of MTBE in drinking water derived from ground water in these States for two near-decadal time steps; 1993-1999 and 2000-2006. MTBE was detected in 14% of drinking water samples collected in all States from 1993-1999 and in 19% of drinking water samples collected from the same systems from 2000-2006 and this difference was statistically significant. Trends in the occurrence of MTBE in each State by individual year indicated significant positive trends in Maryland and New Hampshire. Significant, increasing trends in MTBE concentrations were observed in Maryland and Rhode Island by individual year. This is an abstract of a paper presented at the 2007 Petroleum Hydrocarbons and Organic Chemicals in Ground Water: Prevention, Assessment and Remediation Conference (Houston, TX 11/5-6/2007).

  18. The rapid detection of methyl tert-butyl ether (MtBE) in water using a prototype gas sensor system.

    Science.gov (United States)

    de Lacy Costello, B P J; Sivanand, P S; Ratcliffe, N M; Reynolds, D M

    2005-01-01

    The gasoline additive Methyl-tertiary-Butyl Ether (MtBE) is the second most common contaminant of groundwater in the USA and represents an important soil contaminant. This compound has been detected in the groundwater in at least 27 states as a result of leaking underground storage facilities (gasoline storage tanks and pipelines). Since the health effects of MtBE are unclear the potential threat to drinking water supplies is serious. Therefore, the ability to detect MtBE at low levels (ppb) and on-line at high-risk groundwater sites would be highly desirable. This paper reports the use of 'commercial' and metal oxide sensor arrays for the detection of MtBE in drinking and surface waters at low ppb level (microg.L(-1) range). The output responses from some of the sensors were found to correlate well with MtBE concentrations under laboratory conditions.

  19. Using DNA-Stable Isotope Probing to Identify MTBE- and TBA-Degrading Microorganisms in Contaminated Groundwater.

    Science.gov (United States)

    Key, Katherine C; Sublette, Kerry L; Duncan, Kathleen; Mackay, Douglas M; Scow, Kate M; Ogles, Dora

    2013-01-01

    Although the anaerobic biodegradation of methyl tert -butyl ether (MTBE) and tert -butyl alcohol (TBA) has been documented in the laboratory and the field, knowledge of the microorganisms and mechanisms involved is still lacking. In this study, DNA-stable isotope probing (SIP) was used to identify microorganisms involved in anaerobic fuel oxygenate biodegradation in a sulfate-reducing MTBE and TBA plume. Microorganisms were collected in the field using Bio-Sep® beads amended with 13 C 5 -MTBE, 13 C 1 -MTBE (only methoxy carbon labeled), or 13 C 4 -TBA. 13 C-DNA and 12 C-DNA extracted from the Bio-Sep beads were cloned and 16S rRNA gene sequences were used to identify the indigenous microorganisms involved in degrading the methoxy group of MTBE and the tert -butyl group of MTBE and TBA. Results indicated that microorganisms were actively degrading 13 C-labeled MTBE and TBA in situ and the 13 C was incorporated into their DNA. Several sequences related to known MTBE- and TBA-degraders in the Burkholderiales and the Sphingomonadales orders were detected in all three 13 C clone libraries and were likely to be primary degraders at the site. Sequences related to sulfate-reducing bacteria and iron-reducers, such as Geobacter and Geothrix , were only detected in the clone libraries where MTBE and TBA were fully labeled with 13 C, suggesting that they were involved in processing carbon from the tert -butyl group. Sequences similar to the Pseudomonas genus predominated in the clone library where only the methoxy carbon of MTBE was labeled with 13 C. It is likely that members of this genus were secondary degraders cross-feeding on 13 C-labeled metabolites such as acetate.

  20. Elucidating MTBE degradation in a mixed consortium using a multidisciplinary approach.

    Science.gov (United States)

    Bastida, Felipe; Rosell, Mònica; Franchini, Alessandro G; Seifert, Jana; Finsterbusch, Stefanie; Jehmlich, Nico; Jechalke, Sven; von Bergen, Martin; Richnow, Hans H

    2010-08-01

    The structure and function of a microbial community capable of biodegrading methyl-tert-butyl ether (MTBE) was characterized using compound-specific stable isotope analysis (CSIA), clone libraries and stable isotope probing of proteins (Protein-SIP). The enrichment culture (US3-M), which originated from a gasoline-impacted site in the United States, has been enriched on MTBE as the sole carbon source. The slope of isotopic enrichment factors (epsilon(C) of -2.29+/-0.03 per thousand; epsilon(H) of -58+/-6 per thousand) for carbon and hydrogen discrimination (Deltadelta(2)H/Deltadelta(13)C) was on average equal to Lambda=24+/-2, a value closely related to the reaction mechanism of MTBE degradation in Methylibium petroleiphilum PM1. 16S rRNA gene libraries revealed sequences belonging to M. petroleiphilum PM1, Hydrogenophaga sp., Thiothrix unzii, Rhodobacter sp., Nocardiodes sp. and different Sphingomonadaceae bacteria. Protein-SIP analysis of the culture grown on (13)C-MTBE as the only carbon source revealed that proteins related to members of the Comamonadaceae family, such as Delftia acidovorans, Acidovorax sp. or Comamonas sp., were not (13)C-enriched, whereas proteins related to M. petroleiphilum PM1 showed an average incorporation of 94.5 atom%(13)C. These results indicate a key role for this species in the degradation of MTBE within the US3-M consortia. The combination of CSIA, molecular biology and Protein-SIP facilitated the analysis of an MTBE-degrading mixed culture from a functional and phylogenetic point of view.

  1. Volatile Fuel Hydrocarbons and MTBE in the Environment

    Science.gov (United States)

    Cozzarelli, I. M.; Baehr, A. L.

    2003-12-01

    Petroleum hydrocarbons (hydrocarbons that result from petroleum products such as oil, gasoline, or diesel fuel) are among the most commonly occurring and widely distributed contaminants in the environment. Volatile hydrocarbons are the lighter fraction of the petroleum hydrocarbons and, together with fuel oxygenates, are most often released from crude oil and liquid petroleum products produced from crude oil. The demand for crude oil stems from the world's ever-growing energy need. From 1970 to 1999, primary energy production of the world grew by 76% (Energy Information Administration, 2001), with fossil fuels (crude oil, natural gas, and coal) accounting for ˜85% of all energy produced worldwide (Figure 1). World crude oil production reached a record 68 million barrels (bbl) per day (1.08×1010 L d-1) in 2000. The world's dependence on oil as an energy source clearly is identified as contributing to global warming and worsening air and water quality. (7K)Figure 1. World primary energy production by source from 1970 to 1999 (Energy Information Administration, 2001). Petroleum products are present in Earth's subsurface as solids, liquids, or gases. This chapter presents a summary of the environmental problems and issues related to the use of liquid petroleum, or oil. The focus is on the sources of volatile hydrocarbons and fuel oxygenates and the geochemical behavior of these compounds when they are released into the environment. Although oxygenates currently in commercial use include compounds other than methyl t-butyl ether (MTBE), such as ethanol (ETOH), most of the information presented here focuses on MTBE because of its widespread occurrence. The environmental impact of higher molecular weight hydrocarbons that also originate from petroleum products is described in (Chapter 9.13, Abrajano et al.).Crude oil occurs within the Earth and is a complex mixture of natural compounds composed largely of hydrocarbons containing only hydrogen and carbon atoms. The minor

  2. Review of quantitative surveys of the length and stability of MTBE, TBA, and benzene plumes in groundwater at UST sites.

    Science.gov (United States)

    Connor, John A; Kamath, Roopa; Walker, Kenneth L; McHugh, Thomas E

    2015-01-01

    Quantitative information regarding the length and stability condition of groundwater plumes of benzene, methyl tert-butyl ether (MTBE), and tert-butyl alcohol (TBA) has been compiled from thousands of underground storage tank (UST) sites in the United States where gasoline fuel releases have occurred. This paper presents a review and summary of 13 published scientific surveys, of which 10 address benzene and/or MTBE plumes only, and 3 address benzene, MTBE, and TBA plumes. These data show the observed lengths of benzene and MTBE plumes to be relatively consistent among various regions and hydrogeologic settings, with median lengths at a delineation limit of 10 µg/L falling into relatively narrow ranges from 101 to 185 feet for benzene and 110 to 178 feet for MTBE. The observed statistical distributions of MTBE and benzene plumes show the two plume types to be of comparable lengths, with 90th percentile MTBE plume lengths moderately exceeding benzene plume lengths by 16% at a 10-µg/L delineation limit (400 feet vs. 345 feet) and 25% at a 5-µg/L delineation limit (530 feet vs. 425 feet). Stability analyses for benzene and MTBE plumes found 94 and 93% of these plumes, respectively, to be in a nonexpanding condition, and over 91% of individual monitoring wells to exhibit nonincreasing concentration trends. Three published studies addressing TBA found TBA plumes to be of comparable length to MTBE and benzene plumes, with 86% of wells in one study showing nonincreasing concentration trends. © 2014 GSI Environmental Inc. Groundwater published by Wiley Periodicals, Inc. on behalf of National Ground Water Association.

  3. Tabagisme et dysfonction erectile chez les personnes vivant avec le ...

    African Journals Online (AJOL)

    La dysfonction erectile (DE) est un probleme de sante publique qui altere la qualite de vie des patients. Chez les personnes infectees par le VIH, le tabagisme en association ii d'autres facteurs pourrait accroitre le risque de survenue de ce trouble. L'objectif de cette etude est de determiner la prevalence de laDE, les ...

  4. Depression chez l'hemiplegique vasculaire a Brazzaville | Ossou ...

    African Journals Online (AJOL)

    L'évolution à 6 mois n'a pas été favorable chez 65,7 % des patients. ... Sa prise en charge permettrait assurément d'améliorer la qualité de vie des patients, ... The management of post-stroke depression certainly improves the quality of life of ...

  5. Inobservance therapeutique aux anti-retroviraux chez les personnes ...

    African Journals Online (AJOL)

    Buts : Rechercher les facteurs psychologiques ou psychosociaux responsables de l'inobservance thérapeutique (IBT) aux antiretroviraux (ARV) Méthodologie : Il s'agit d'une étude transversale sur 06 mois (mai - octobre 2008) menée au centre de promotion sociale à Lomé chez les personnes vivant avec le VIH (PVVIH) ...

  6. Risque de transmission sexuelle chez les personnes vivant avec le ...

    African Journals Online (AJOL)

    Contexte : Depuis 1996, les traitements du sida ont permis de changer le visage de la maladie. Un traitement efficace ... Conclusion : Cette étude a décrit que le risque de transmission sexuelle des infections sexuellement transmissibles (IST) existe chez les PVVIH à cause des rapports sexuels à risque. D'autres études ...

  7. Efficacite de la bitherapie raltegravir-etravirine chez les ...

    African Journals Online (AJOL)

    Efficacite de la bitherapie raltegravir-etravirine chez les immunodeprimes au VIH. D Traore, A Simon, N Sawadogo, S.A. Coulibaly, D.S. Sow, A.S. Kaya, M Dembélé, A.K. Traoré, H.A. Traoré, S Herson ...

  8. BTEX MTBE BIOREMEDIATION: BIONETS CONTAINING ISOLITE, PM1, SOLID OXYGEN SOURCE

    Science.gov (United States)

    Methyl tert-Butyl Ether (MTBE), a gasoline additive, is a persistent and foul tasting contaminate that is more mobile in ground water than BTEX . It, along with BTEX, is turning up at many American crossroads. This study's objective was to determine if biologically active in sit...

  9. MTBE BIODEGRADATION IN A GRAVITY FLOW, HIGH-BIOMASS RETAINING BIOREACTOR

    Science.gov (United States)

    The aerobic biodegradation of methyl tert-butyl ether (MtBE), a widely used fuel oxygenate, was investigated using a pilot-scale biomass-retaining bioreactor called a Biomass Concentrator Reactor (BCR). The reactor was operated for a year at a flow rate of 2500 L/d on Ci...

  10. REMOVAL OF MTBE FROM WATER BY MEMBRANE-BASED PERVAPORATION TECHNOLOGY

    Science.gov (United States)

    The ability of pervaporation to remove methyl t-butyl ether (MTBE) from water has been evaluated at both bench- and pilot-scales. In pervaporation, a liquid stream containing two or more components is placed in contact with one side of a non-porous polymeric membrane while a vac...

  11. MTBE BIOREMEDIATION WITH BIONETS CONTAINING ISOLITE®, PM1, SOLID OXYGEN SOURCE (SOS) OR AIR

    Science.gov (United States)

    MTBE, a gasoline additive, is a persistent and foul tasting contaminant that is more mobile in groundwater than BTEX (benzene, toluene, ethylbenzene, xylenes). It is turning up at many American crossroads. The objective of this well controlled study was to determine if biological...

  12. MTBE BIOREMEDIATION WITH BIONETS(TM) CONTAINING ISOLITE, PM1, SOLD OXYGEN SOURCE (SOS) OR AIR

    Science.gov (United States)

    MTBE, a gasoline additive, is a persistent and foul tasting contaminant that is more mobile in groundwater than BTEX (benzene, toluene, ethylbenzene, xylenes). It is turning up at many American crossroads. The objective of this well controlled study was to determine if biological...

  13. STABLE ISOTOPE ANALYSIS OF MTBE TO EVALUATE THE SOURCE OF TBA IN GROUND WATER

    Science.gov (United States)

    Although tert-butyl alcohol (TBA) has not been used as a fuel oxygenate in Orange County, California, the concentrations of TBA in ground water at gasoline spill sites are high compared those of the conventional fuel oxygenate methyl tert-butyl ether (MTBE). In the year 2002, th...

  14. MONITORED NATURAL ATTENUATION AND RISK MANAGEMENT OF MTBE AND TBA IN GROUND WATER

    Science.gov (United States)

    Monitored natural attenuation (as U.S. EPA defines the term) is a remedy, where natural processes bring the concentration of MTBE or TBA to an acceptable level in a reasonable period of time. The longevity of the plume is its critical property. The rate of attenuation is typica...

  15. Investigation of MTBE and aromatic compound concentrations at a gas service station.

    Science.gov (United States)

    Lin, Chi-Wen; Chiang, Song-Bor; Lu, San-Ju

    2005-06-01

    Methyl tert-butyl ether (MTBE) has been used as a fuel additive at levels of 2-11% in Taiwan for the past decade. The purpose of this additive is to enhance the octane, replace the use of lead-based anti-knock gasoline additives and reduce aromatic hydrocarbons. However, it is possible that oxygenated fuel has a potential health impact. To determine the air quality impact of MTBE, measurements were made of ambient MTBE and other gasoline constituents at a service station. Additionally, environmental conditions (wind speed, wind direction, and temperature, etc.) that could affect concentrations of emission constituents were measured. Gas samples were analyzed for target MTBE and volatile organic compounds, e.g., benzene and toluene. Ambient samples were collected using Tenax adsorbent tubes for mass spectrometric analysis at a service station located in Changhua County, Taiwan. The resulting measured ambient air concentrations were compared with Taiwan's regulatory standards for hazardous air pollutants. Subsequently, the factors controlling the formation of high-VOC levels at the service station and in the residential neighborhoods were identified. Additionally, the results can provide the Environmental Protection Agency (EPA) of Taiwan with useful information and prompt them to mandate this gas service station to install a refueling vapor recovery system.

  16. DERMAL, ORAL, AND INHALATION PHARMACOKINETICS OF METHYL TERTIARY BUTYL ETHER (MTBE) IN HUMAN VOLUNTEERS

    Science.gov (United States)

    Methyl tertiary butyl ether (MTBE), a gasoline additive, used to increase octane and reduce carbon monoxide emissions and ozone precursors has contaminated drinking water leading to exposure by oral, inhalation, and dermal routes. To determine its dermal, oral, and inhalation ki...

  17. DERMAL, ORAL AND INHALATION PHARMACOKINETICS OF METHYL TERTIARY-BUTYL ETHER (MTBE) IN HUMAN VOLUNTEERS

    Science.gov (United States)

    Methyl tertiary butyl ether (MTBE), a gasoline additive used to increase octane and reduce carbon monoxide emissions and ozone precursors, has contaminated drinking water and can lead to exposure by oral, inhalation, and dermal routes. To determine its dermal, oral, and inhal...

  18. Monitoring of the Gasoline Oxygenate MTBE and BTEX Compounds in Groundwater in Catalonia (Northeast Spain

    Directory of Open Access Journals (Sweden)

    J. Fraile

    2002-01-01

    Full Text Available Headspace (HS gas chromatography with flame ionisation detection (HS-GC-FID and purge and trap (P gas chromatography-mass spectrometry (P were used for the determination of methyl-tert-butyl ether (MTBE and benzene, toluene, and xylenes (BTEX in groundwater. In this work, we present the first data on the levels of MTBE and BTEX in different groundwater wells in the area of Catalonia (northeast Spain. This monitoring campaign corresponded to 28 groundwater wells that were located near petrol service stations, oil refinery storage tanks, and/or chemical industry at different locations of Catalonia during the period of 1998/1999. The levels of MTBE detected varied between 4—300 μg/l, but two sites had MTBE levels up to 3 and 13 mg/l. In many cases, the BTEX levels were below 1 μg/l, whereas 7 sites had levels varying from 19 μg/l up to 3 mg/l. Most of them were related to leakage from underground tanks in petrol service stations, while the remaining three corresponded respectively to chemical industrial pollution of undetermined origin and to a leak from high-ground petrol tanks in petrochemical refinery factories. The aquifers involved were constituted by detritus coarse materials, sands, and conglomerates. Piezometric levels were roughly comprised between 3 and 40 m, and permeability (K and transmissivity (T values were estimated from field measurements.

  19. NOVEL EMBEDDED CERAMIC ELECTRODE SYSTEM TO ACTIVATE NANOSTRUCTURED TITANIUM DIOXIDE FOR DEGRADATION OF MTBE

    Science.gov (United States)

    A novel reactor combining a flame-deposited nanostructured titanium dioxide film and a set of embedded ceramic electrodes was designed, developed and tested for degradation of methyl tert-butyl ether (MTBE) in water. On applying a voltage to the ceramic electrodes, a surface coro...

  20. Particle Size Effects on Fenton Regeneration of MTBE-spent Activated Carbon

    Science.gov (United States)

    Fenton-driven regeneration of spent granular activated carbon (GAC) is a developing technology that may reduce water treatment costs. In this study, the effect of GAC particle size on Fenton-driven oxidation of methyl tert-butyl ether (MTBE)-spent GAC was evaluated. The GAC was...

  1. Fenton-Driven Regeneration of MTBE-spent Granular Activated Carbon

    Science.gov (United States)

    Fenton-driven regeneration of Methyl tert-butyl ether (MTBE)-spent granular activated carbon (GAC) involves the combined, synergistic use of two treatment technologies: adsorption of organic chemicals onto activated carbon and Fenton-driven oxidation regeneration of the spent-GAC...

  2. Analysis of dissolved benzene plumes and methyl tertiary butyl ether (MTBE) plumes in ground water at leaking underground fuel tank (LUFT) sites

    International Nuclear Information System (INIS)

    Happel, A.M.; Rice, D.; Beckenbach, E.; Savalin, L.; Temko, H.; Rempel, R.; Dooher, B.

    1996-11-01

    The 1990 Clean Air Act Amendments mandate the addition of oxygenates to gasoline products to abate air pollution. Currently, many areas of the country utilize oxygenated or reformulated fuel containing 15- percent and I I-percent MTBE by volume, respectively. This increased use of MTBE in gasoline products has resulted in accidental point source releases of MTBE containing gasoline products to ground water. Recent studies have shown MTBE to be frequently detected in samples of shallow ground water from urban areas throughout the United States (Squillace et al., 1995). Knowledge of the subsurface fate and transport of MTBE in ground water at leaking underground fuel tank (LUFT) sites and the spatial extent of MTBE plumes is needed to address these releases. The goal of this research is to utilize data from a large number of LUFT sites to gain insights into the fate, transport, and spatial extent of MTBE plumes. Specific goals include defining the spatial configuration of dissolved MTBE plumes, evaluating plume stability or degradation over time, evaluating the impact of point source releases of MTBE to ground water, and attempting to identify the controlling factors influencing the magnitude and extent of the MTBE plumes. We are examining the relationships between dissolved TPH, BTEX, and MTBE plumes at LUFT sites using parallel approaches of best professional judgment and a computer-aided plume model fitting procedure to determine plume parameters. Here we present our initial results comparing dissolved benzene and MTBE plumes lengths, the statistical significance of these results, and configuration of benzene and MTBE plumes at individual LUFT sites

  3. Epigenetic and Transcriptional Modifications in Repetitive Elements in Petrol Station Workers Exposed to Benzene and MTBE

    Directory of Open Access Journals (Sweden)

    Federica Rota

    2018-04-01

    Full Text Available Benzene, a known human carcinogen, and methyl tert-butyl ether (MTBE, not classifiable as to its carcinogenicity, are fuel-related pollutants. This study investigated the effect of these chemicals on epigenetic and transcriptional alterations in DNA repetitive elements. In 89 petrol station workers and 90 non-occupationally exposed subjects the transcriptional activity of retrotransposons (LINE-1, Alu, the methylation on repeated-element DNA, and of H3K9 histone, were investigated in peripheral blood lymphocytes. Median work shift exposure to benzene and MTBE was 59 and 408 µg/m3 in petrol station workers, and 4 and 3.5 µg/m3, in controls. Urinary benzene (BEN-U, S-phenylmercapturic acid, and MTBE were significantly higher in workers than in controls, while trans,trans-muconic acid (tt-MA was comparable between the two groups. Increased BEN-U was associated with increased Alu-Y and Alu-J expression; moreover, increased tt-MA was associated with increased Alu-Y and Alu-J and LINE-1 (L1-5′UTR expression. Among repetitive element methylation, only L1-Pa5 was hypomethylated in petrol station workers compared to controls. While L1-Ta and Alu-YD6 methylation was not associated with benzene exposure, a negative association with urinary MTBE was observed. The methylation status of histone H3K9 was not associated with either benzene or MTBE exposure. Overall, these findings only partially support previous observations linking benzene exposure with global DNA hypomethylation.

  4. L’amor humanus chez Marsile Ficin

    Directory of Open Access Journals (Sweden)

    Laurence Boulègue

    2010-12-01

    Full Text Available Les éditions et études du Commentaire sur le Banquet de Platon, ou De amore, de Marsile Ficin ont mis en évidence que la conception de Vamor humanus chez l'humaniste florentin, inspirée certes des définitions du Banquet de Platon, était étroitement liée aux conceptions néoplatoniciennes héritées de Plotin. Néanmoins, l'interprétation du texte de Platon et les développements de ses successeurs ne sauraient à eux seuls rendre compte de la définition ficinienne, notamment dans son lien avec la notion, romaine, de la fascinatio. La philosophie et la poésie romaines des passions offrent une analyse du sentiment amoureux dont les échos sont sensibles dans le texte même du Commentaire. En effet, l'exposé des passions qu'offre le livre IV des Tusculanes a sans aucun doute fourni à Ficin les caractéristiques et la définition du « mauvais amour », dont l'évocation n'est pas étrangère aux motifs poétiques tels qu'on peut les trouver, par exemple, dans la poésie ovidienne à propos du mythe de Narcisse, dont Ficin se souvient. Si Cicéron soulignait, au début du livre IV des Tusculanes, la tension qui existait entre l'anthropologie platonicienne et la théorie des passions stoïcienne, il ne la résolvait pas. Ficin, lui, réalise cette articulation grâce à la hiérarchisation néoplatonicienne des différents amours et peut ainsi affirmer l'existence d'un bon amour. Mais un tel amor humanus, qui est amour philopédique, destiné à l'élévation divine ou voué à s'affaisser jusqu'à la concupiscence bestiale, ne peut être qu'un moment dans le processus proposé par Ficin, un point de fragile équilibre, intenable.

  5. Location of MTBE and toluene in the channel system of the zeolite mordenite: Adsorption and host-guest interactions

    Energy Technology Data Exchange (ETDEWEB)

    Arletti, Rossella, E-mail: rossella.arletti@unito.it [Department of Earth Sciences, University of Torino Via Valperga Caluso 35, I-10125, Torino (Italy); Martucci, Annalisa; Alberti, Alberto [Department of Earth Sciences, University of Ferrara, Via G. Saragat 1, I-44100, Ferrara (Italy); Pasti, Luisa; Nassi, Marianna [Department of Chemistry, University of Ferrara, Via L. Borsari 26, I-44100 Ferrara (Italy); Bagatin, Roberto [Research Centre for Non-Conventional Energy-Istituto ENI Donegani, Environmental Technologies, Via Fauser 4, I-28100 Novara (Italy)

    2012-10-15

    This paper reports a study of the location of Methyl Tertiary Butyl Ether (MTBE) and toluene molecules adsorbed in the pores of the organophylic zeolite mordenite from an aqueous solution. The presence of these organic molecules in the zeolite channels was revealed by structure refinement performed by the Rietveld method. About 3 molecules of MTBE and 3.6 molecules of toluene per unit cell were incorporated into the cavities of mordenite, representing 75% and 80% of the total absorption capacity of this zeolite. In both cases a water molecule was localized inside the side pocket of mordenite. The saturation capacity determined by the adsorption isotherms, obtained by batch experiments, and the weight loss given by thermogravimetric (TG) analyses were in very good agreement with these values. The interatomic distances obtained after the structural refinements suggest MTBE could be connected to the framework through a water molecule, while toluene could be bonded to framework oxygen atoms. The rapid and high adsorption of these hydrocarbons into the organophylic mordenite zeolite makes this cheap and environmental friendly material a suitable candidate for the removal of these pollutants from water. - graphical abstract: Location of MTBE (a) and toluene (b) in mordenite channels (projection along the [001] direction). Highlights: Black-Right-Pointing-Pointer We investigated the MTBE and toluene adsorption process into an organophilic zeolite mordenite. Black-Right-Pointing-Pointer The presence of MTBE and toluene in mordenite was determined by X-ray diffraction studies. Black-Right-Pointing-Pointer About 3 molecules of MTBE and 3.6 molecules of toluene per unit cell were incorporated into the zeolite cavities. Black-Right-Pointing-Pointer MTBE is connected to the framework through a water molecule. Black-Right-Pointing-Pointer Toluene is directly bonded to framework oxygen atoms.

  6. Two-year drinking water carcinogenicity study of methyl tertiary-butyl ether (MTBE) in Wistar rats.

    Science.gov (United States)

    Dodd, Darol; Willson, Gabrielle; Parkinson, Horace; Bermudez, Edilberto

    2013-07-01

    Methyl tertiary-butyl ether (MTBE) has been used as a gasoline additive to reduce tailpipe emissions and its use has been discontinued. There remains a concern that drinking water sources have been contaminated with MTBE. A two-year drinking water carcinogenicity study of MTBE was conducted in Wistar rats (males, 0, 0.5, 3, 7.5 mg ml(-1); and females, 0, 0.5, 3, and 15 mg ml(-1)). Body weights were unaffected and water consumption was reduced in MTBE-exposed males and females. Wet weights of male kidneys were increased at the end of two years of exposure to 7.5 mg ml(-1) MTBE. Chronic progressive nephropathy was observed in males and females, was more severe in males, and was exacerbated in the high MTBE exposure groups. Brain was the only tissue with a statistically significant finding of neoplasms. One astrocytoma (1/50) was found in a female rat (15 mg ml(-1)). The incidence of brain astrocytomas in male rats was 1/50, 1/50, 1/50 and 4/50 for the 0, 0.5, 3 and 7.5 mg ml(-1) exposure groups, respectively. This was a marginally significant statistical trend, but not statistically significant when pairwise comparisons were made or when multiple comparisons were taken into account. The incidence of astrocytoma fell within historical control ranges for Wistar rats, and the brain has not been identified as a target organ following chronic administration of MTBE, ethyl tert-butyl ether, or tertiary butyl alcohol (in drinking water) to mice and rats. We conclude that the astrocytomas observed in this study are not associated with exposure to MTBE. Copyright © 2011 John Wiley & Sons, Ltd.

  7. Role of back diffusion and biodegradation reactions in sustaining an MTBE/TBA plume in alluvial media.

    Science.gov (United States)

    Rasa, Ehsan; Chapman, Steven W; Bekins, Barbara A; Fogg, Graham E; Scow, Kate M; Mackay, Douglas M

    2011-11-01

    A methyl tert-butyl ether (MTBE) / tert-butyl alcohol (TBA) plume originating from a gasoline spill in late 1994 at Vandenberg Air Force Base (VAFB) persisted for over 15 years within 200 feet of the original spill source. The plume persisted until 2010 despite excavation of the tanks and piping within months after the spill and excavations of additional contaminated sediments from the source area in 2007 and 2008. The probable history of MTBE concentrations along the plume centerline at its source was estimated using a wide variety of available information, including published details about the original spill, excavations and monitoring by VAFB consultants, and our own research data. Two-dimensional reactive transport simulations of MTBE along the plume centerline were conducted for a 20-year period following the spill. These analyses suggest that MTBE diffused from the thin anaerobic aquifer into the adjacent anaerobic silts and transformed to TBA in both aquifer and silt layers. The model reproduces the observation that after 2004 TBA was the dominant solute, diffusing back out of the silts into the aquifer and sustaining plume concentrations much longer than would have been the case in the absence of such diffusive exchange. Simulations also suggest that aerobic degradation of MTBE or TBA at the water table in the overlying silt layer significantly affected concentrations of MTBE and TBA by limiting the chemical mass available for back diffusion to the aquifer. Copyright © 2011 Elsevier B.V. All rights reserved.

  8. Perception urbaine, distraction et stratification chez Benjamin, Eisenstein et Vertov

    OpenAIRE

    Rousse, Pascal

    2008-01-01

    La ville à l’écran est le substrat imaginaire et historique du cinéma. Mais le cinéma, burlesque et soviétique, transforme ce contexte tout en constituant sa mémoire. Walter Benjamin inaugura cette problématique avec la notion de « distraction », liant architecture et cinéma sur le fond du paradigme de la stratification de l’appareil psychique chez Freud.

  9. Rates and products of degradation for MTBE and other oxygenate fuel additives in the subsurface environment

    International Nuclear Information System (INIS)

    Tratnyek, P.G.; Church, C.D.; Pankow, J.F.

    1995-01-01

    The recent realization that oxygenated fuel additives such as MTBE are becoming widely distributed groundwater contaminants has created a sudden and pressing demand for data on the processes that control their environmental fate. Explaining and predicting the subsequent environmental fate of these compounds is going to require extrapolations over long time frames that will be very sensitive to the quality of input data on each compound. To provide such data, they have initiated a systematic study of the pathways and kinetics of fuel oxygenate degradation under subsurface conditions. Batch experiments in simplified model systems are being performed to isolate specific processes that may contribute to MTBE degradation. A variety of degradation pathways can be envisioned that lead to t-butyl alcohol (TBA) as the primary or secondary product. However, experiments to date with a facultative iron reducing bacteria showed no evidence for TBA formation. Continuing experiments include mixed cultures from a range of aquifer materials representative of NAWQA study sites

  10. Physiologically based pharmacokinetic rat model for methyl tertiary-butyl ether; comparison of selected dose metrics following various MTBE exposure scenarios used for toxicity and carcinogenicity evaluation

    International Nuclear Information System (INIS)

    Borghoff, Susan J.; Parkinson, Horace; Leavens, Teresa L.

    2010-01-01

    There are a number of cancer and toxicity studies that have been carried out to assess hazard from methyl tertiary-butyl ether (MTBE) exposure via inhalation and oral administration. MTBE has been detected in surface as well as ground water supplies which emphasized the need to assess the risk from exposure via drinking water contamination. This model can now be used to evaluate route-to-route extrapolation issues concerning MTBE exposures but also as a means of comparing potential dose metrics that may provide insight to differences in biological responses observed in rats following different routes of MTBE exposure. Recently an updated rat physiologically based pharmacokinetic (PBPK) model was published that relied on a description of MTBE and its metabolite tertiary-butyl alcohol (TBA) binding to α2u-globulin, a male rat-specific protein. This model was used to predict concentrations of MTBE and TBA in the kidney, a target tissue in the male rat. The objective of this study was to use this model to evaluate the dosimetry of MTBE and TBA in rats following different exposure scenarios, used to evaluate the toxicity and carcinogenicity of MTBE, and compare various dose metrics under these different conditions. Model simulations suggested that although inhalation and drinking water exposures show a similar pattern of MTBE and TBA exposure in the blood and kidney (i.e. concentration-time profiles), the total blood and kidney levels following exposure of MTBE to 7.5 mg/ml MTBE in the drinking water for 90 days is in the same range as administration of an oral dose of 1000 mg/kg MTBE. Evaluation of the dose metrics also supports that a high oral bolus dose (i.e. 1000 mg/kg MTBE) results in a greater percentage of the dose exhaled as MTBE with a lower percent metabolized to TBA as compared to dose of MTBE that is delivered over a longer period of time as in the case of drinking water.

  11. Potential occurrence of MTBE and BTEX in groundwater resources of Amman-Zarqa basin, Jordan

    International Nuclear Information System (INIS)

    Al Kuisi, Mustafa; Saffarini, Ghazi; Yaseen, Najal; Alawi, Mahmoud

    2012-01-01

    This study investigates potential occurrence, distribution, and sources of the newly added gasoline oxygenate, methyl-tert-butyl ether (MTBE) and the petroleum derivatives benzene, toluene, ethylbenzene, and xylenes called collectively, BTEX, in Jordan's heavily populated Amman-Zarqa Basin (AZB). It presents the first data on the levels of MTBE and BTEX in the aquifers of this basin. One hundred and seventy-nine (179) groundwater wells were sampled near petrol service stations, oil refinery storage tanks, car wrecks, bus stations, and chemical industries at different locations in the basin. Headspace GC and purge and trap GC-MS were utilized to determine the target substances in the samples. Concentrations of BTEX varied between no-detection (minimum) for all of them to 6.6 μg/L (maximum) for ethylbenzene. MTBE was found in few samples but none has exceeded the regulated levels; its concentrations ranged between no-detection to 4.1 μg/L. However, though the contamination levels are very low they should be considered alarming. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  12. The Effect of Water Contaminated with Methyl Tertiary Butyl Ether (MTBE) on the Rat's Weight and Tissue

    International Nuclear Information System (INIS)

    Backer, Wadiah Saleh; AboKhatwa, Ahmed Nabil; Katouah, Hanadi Ahmed

    2008-01-01

    Lead is known to cause deleterious effects on health and environment. Therefore, it was removed from car-fuel, in the United States since 1979. In January 2001, Saudi Arabia and other Arabian Gulf States, replaced lead with a synthetic organic substance called methyl tertiary-butyl ether (MTBE). MTBE is added to gasoline at 12-15%. It dissolves readily in water and evaporates quickly. This study was focused on the possible health hazards of MTBE in drinking water as manifested by changes in weight and vital tissues (heart, liver, kidney, lung, and testis) of rat. This study also aimed to establish a quantitative relationship between MTBE concentration and changes that occur to these tissues. One hundred and twenty male Wistar rats were exposed to five different MTBE concentrations (0.0, 1,000, 1,500, 2,000, 2,500 ppm) for 60 days. The results showed that most of MTBE-treated animals have revealed significant weight loss and the maximum weight loss (nearly 10 %) was achieved at the highest concentration (2,500 ppm) after 60 days of treatment. Also, both liver and heart weights were significantly reduced by almost 9%, and kidneys by 8% of MTBE concentration of 2,000 ppm. At a higher concentration (2,500 ppm), liver weight was reduced by 12%. The weight of other tissues (lungs and testes) remained unchanged. The outcome of the results may lead to hepatic disorder. This disorder could reduce plasma glucose, or increase some hepatic markers like ALT, AST, and GGT activity, or elevate the levels of sodium and chloride in plasma and may have other side effects. (author)

  13. Sorption of methyl tert-butyl ether (MTBE) and tert-butyl alcohol (TBA) to synthetic resins.

    Science.gov (United States)

    Bi, Erping; Haderlein, Stefan B; Schmidt, Torsten C

    2005-10-01

    Methyl tert-butyl ether (MTBE) is a widely used gasoline oxygenate. Contamination of MTBE and its major degradation product tert-butyl alcohol (TBA) in groundwater and surface water has received great attention. However, sorption affinity and sorption mechanisms of MTBE and TBA to synthetic resins, which can be potentially used in removal of these contaminants from water, in passive sampling, or in enrichment of bacteria, have not been studied systemically. In this study, kinetic and equilibrium sorption experiments (single solute and binary mixtures) on four synthetic resins were conducted. The sorption affinity of the investigated sorbents for MTBE and TBA decreases in the order Ambersorb 563>Optipore L493>Amberlite XAD4>Amberlite XAD7, and all show higher sorption affinity for MTBE than for TBA. Binary experiments with o-xylene, a major compound of gasoline as co-contaminant, imply that all resins preferentially sorb o-xylene over MTBE or TBA, i.e., there is sorption competition. In the equilibrium aqueous concentration (Ceq) range (0.1-139.0 mg/L for MTBE, and 0.01-48.4 mg/L for TBA), experimental and modeling results as well as sorbent characteristics indicate that micropore filling and/or some other type of adsorption process (e.g., adsorption to specific sites of high sorption potential at low concentrations) rather than partitioning were the dominant sorption mechanisms. Optipore L493 has favourable sorption and desorption characteristics, and is a suitable sorbent, e.g., in bacteria enrichment or passive sampling for moderately polar compounds. However, for highly polar compounds such as TBA, Ambersorb 563 might be a better choice, especially in water treatment.

  14. In vitro Inhibition of Mycobacterium smegmatis and Mycobacterium ...

    African Journals Online (AJOL)

    Some Nigerian plants used in traditional medicine to treat tuberculosis and/or some of its symptoms were screened for in vitro activity against Mycobacterium smegmatis and a clinical isolate of Mycobacterium tuberculosis. Only 3 of the 6 crude methanolic extracts of the 6 plant species exhibited inhibitory activities against ...

  15. Preparation and characterization of Pd doped ceria–ZnO nanocomposite catalyst for methyl tert-butyl ether (MTBE) photodegradation

    International Nuclear Information System (INIS)

    Seddigi, Zaki S.; Bumajdad, Ali; Ansari, Shahid P.; Ahmed, Saleh A.; Danish, Ekram Y.; Yarkandi, Naeema H.; Ahmed, Shakeel

    2014-01-01

    Highlights: • Novel Pd supported ceria–ZnO photocatalysts were prepared with different amounts of palladium. • The photocatalytic activity of these catalysts was evaluated for degradation of MTBE in water. • Near complete removal of MTBE was achieved using 1% Pd doped ceria–ZnO catalyst and UV irradiation. • Highest rate constant was obtained in case of 1% Pd doped ceria–ZnO catalyst. • Shape and size of pores are important factors for high photoactivity of catalyst. -- Abstract: A series of binary oxide catalysts (ceria–ZnO) were prepared and doped with different amounts of palladium in the range of 0.5%–1.5%. The prepared catalysts were characterized by SEM, TEM, XRD and XPS, as well as by N 2 sorptiometry study. The XPS results confirmed the structure of the Pd CeO 2−x -ZnO. The photocatalytic activity of these catalysts was evaluated for degradation of MTBE in water. These photocatalyst efficiently degrade a 100 ppm aqueous solution of MTBE upon UV irradiation for 5 h in the presence of 100 mg of each of these photocatalysts. The removal of 99.6% of the MTBE was achieved with the ceria–ZnO catalyst doped with 1% Pd. In addition to the Pd loading, the N 2 sorptiometry study introduced other factors that might affect the catalytic efficiency is the catalyst average pore sizes. The photoreaction was determined to be a first order reaction

  16. Preparation and characterization of Pd doped ceria–ZnO nanocomposite catalyst for methyl tert-butyl ether (MTBE) photodegradation

    Energy Technology Data Exchange (ETDEWEB)

    Seddigi, Zaki S. [Chemistry Department, Umm Al-Qura University, Makkah (Saudi Arabia); Bumajdad, Ali [Chemistry Department, Faculty of Science, Kuwait University (Kuwait); Ansari, Shahid P. [Chemistry Department, Umm Al-Qura University, Makkah (Saudi Arabia); Ahmed, Saleh A., E-mail: saleh_63@hotmail.com [Chemistry Department, Umm Al-Qura University, Makkah (Saudi Arabia); Danish, Ekram Y. [Chemistry Department, King Abdulaziz University, Jeddah (Saudi Arabia); Yarkandi, Naeema H. [Chemistry Department, Umm Al-Qura University, Makkah (Saudi Arabia); Ahmed, Shakeel [Center for Refining and Petrochemicals, Research Institute, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia)

    2014-01-15

    Highlights: • Novel Pd supported ceria–ZnO photocatalysts were prepared with different amounts of palladium. • The photocatalytic activity of these catalysts was evaluated for degradation of MTBE in water. • Near complete removal of MTBE was achieved using 1% Pd doped ceria–ZnO catalyst and UV irradiation. • Highest rate constant was obtained in case of 1% Pd doped ceria–ZnO catalyst. • Shape and size of pores are important factors for high photoactivity of catalyst. -- Abstract: A series of binary oxide catalysts (ceria–ZnO) were prepared and doped with different amounts of palladium in the range of 0.5%–1.5%. The prepared catalysts were characterized by SEM, TEM, XRD and XPS, as well as by N{sub 2} sorptiometry study. The XPS results confirmed the structure of the Pd CeO{sub 2−x}-ZnO. The photocatalytic activity of these catalysts was evaluated for degradation of MTBE in water. These photocatalyst efficiently degrade a 100 ppm aqueous solution of MTBE upon UV irradiation for 5 h in the presence of 100 mg of each of these photocatalysts. The removal of 99.6% of the MTBE was achieved with the ceria–ZnO catalyst doped with 1% Pd. In addition to the Pd loading, the N{sub 2} sorptiometry study introduced other factors that might affect the catalytic efficiency is the catalyst average pore sizes. The photoreaction was determined to be a first order reaction.

  17. Definition of purified enzyme-linked immunosorbent assay antigens from the culture filtrate protein of Mycobacterium bovis by proteomic analysis.

    Science.gov (United States)

    Cho, Yun Sang; Lee, Sang-Eun; Ko, Young Joon; Cho, Donghee; Lee, Hyang Shim; Hwang, Inyeong; Nam, Hyangmi; Heo, Eunjung; Kim, Jong Man; Jung, Sukchan

    2009-01-01

    Enzyme-linked immunosorbent assay (ELISA) has been developed as the ancillary diagnosis of bovine tuberculosis at ante-mortem to overcome the disadvantages of intradermal skin test. In this study, the antigenic proteins were purified, applied to bTB ELISA, and identified through proteomic analysis. Culture filtrate protein of Mycobacterium bovis was fractionated by MonoQ column chromatography, and examined the antigenicity by immunoblotting. The antigenic 20 kDa protein was in-gel digested and identified the antigenome by LTQ mass spectrometer and peptide match fingerprinting, which were MPB64, MPB70, MPB83, Fas, Smc, Nrp, RpoC, Transposase, LeuA, and MtbE. The 20 kDa protein exhibited the highest antigenicity to bTB positive cattle in ELISA and would be useful for bTB serological diagnosis.

  18. Production d'isobutène de haute pureté par décomposition du MTBE High-Purity Isobutene Production from Mtbe

    Directory of Open Access Journals (Sweden)

    Meunier P. B.

    2006-11-01

    Full Text Available La décomposition du MTBE en isobutène et méthanol s'accompagne de réactions secondaires (oligomérisation de l'isobutène, hydratation de l'isobutène, déshydratation du méthanol. Les différents types de catalyseurs utilisés, les mécanismes et les cinétiques suggérés, ainsi que les sites actifs et les espèces adsorbées proposés dans la littérature sont examinés dans le cas de la réaction principale, et des réactions secondaires. La formulation du catalyseur et la nature des sites actifs (Brönsted, Lewis ont une incidence particulière sur la réaction. Les données de la littérature portent essentiellement sur des catalyseurs de type résines présentant une acidité de Brönsted. Sur catalyseurs de type oxydes il apparaît que les sites acides de Lewis, catalysent la réaction principale, tandis que les réactions secondaires sont essentiellement dues à la présence d'acidité de Brönsted. Un contrôle de l'acidité des formulations catalytiques est nécessaire afin de minimiser les réactions secondaires, et de produire de l'isobutène très pur. Under suitable conditions, methyl-tert-butyl ether (MTBE is decomposed into isobutene (C4H8 and methanol (CH3OH. This decomposition is a reversible endothermic chemical reaction ((*** = 15. 6 kcal/mol in the gas phase. When this reaction is situated downstream from MTBE synthesis from a C4 cut, this results in the separation of the different isomers in this cut by a less costly method than the one now used, which consists of concentrated sulfuric-acid extraction. The isobutene obtained by MTBE decomposition is very pure and meets the specifications required for subsequent polymerization into butyl rubber or methyl methacrylate. The MTBE decomposition reaction is accompanied by secondary reactions such as the oligomerization of isobutene (mainly the formation of dimers, the dehydration of methanol into dimethylether, and the hydration of isobutene into tert-butyl alcohol. MTBE

  19. Envenimation mortelle par morsure de serpent chez une femme ...

    African Journals Online (AJOL)

    Les auteurs rapportent un cas de morsure de serpent au niveau de la face chez une femme enceinte, dont l'évolution a été marquée par l'installation d'un oedème cervico-facial nécessitant une trachéotomie en urgence, et une mort foetale in utero avec troubles de l'hémostase responsable du décès maternel dans un ...

  20. Stress au travail chez les enseignants: approches diagnostique et ...

    African Journals Online (AJOL)

    Position du problème: déterminer la prévalence et identifier les facteurs déterminants du stress professionnel chez les enseignants de l'école primaire publique au Togo. Méthodes: Il s'agit d'une étude transversale menée sur cinq mois, de décembre 2011 à avril 2012, dans la commune de Lomé et la préfecture du Golfe, ...

  1. Prevalence des hemolysines chez les donneurs de sang de groupe ...

    African Journals Online (AJOL)

    Objectifs : Déterminer la fréquence et le titre des hémolysines anti-A et anti-B dans la population des donneurs O et de prédire de l'intérêt de la systématisation de leur recherche chez tous les donneurs O par l'évaluation du risque d'accident transfusionnels liés aux hémolysines. Méthodologie : Etude prospective au ...

  2. Anaerobic degradation of a mixture of MtBE, EtBE, TBA, and benzene under different redox conditions.

    Science.gov (United States)

    van der Waals, Marcelle J; Pijls, Charles; Sinke, Anja J C; Langenhoff, Alette A M; Smidt, Hauke; Gerritse, Jan

    2018-04-01

    The increasing use of biobased fuels and fuel additives can potentially change the typical fuel-related contamination in soil and groundwater. Anaerobic biotransformation of the biofuel additive ethyl tert-butyl ether (EtBE), as well as of methyl tert-butyl ether (MtBE), benzene, and tert-butyl alcohol (TBA, a possible oxygenate metabolite), was studied at an industrially contaminated site and in the laboratory. Analysis of groundwater samples indicated that in the field MtBE was degraded, yielding TBA as major product. In batch microcosms, MtBE was degraded under different conditions: unamended control, with medium without added electron acceptors, or with ferrihydrite or sulfate (with or without medium) as electron acceptor, respectively. Degradation of EtBE was not observed under any of these conditions tested. TBA was partially depleted in parallel with MtBE. Results of microcosm experiments with MtBE substrate analogues, i.e., syringate, vanillate, or ferulate, were in line with the hypothesis that the observed TBA degradation is a cometabolic process. Microcosms with ferulate, syringate, isopropanol, or diethyl ether showed EtBE depletion up to 86.5% of the initial concentration after 83 days. Benzene was degraded in the unamended controls, with medium without added electron acceptors and with ferrihydrite, sulfate, or chlorate as electron acceptor, respectively. In the presence of nitrate, benzene was only degraded after addition of an anaerobic benzene-degrading community. Nitrate and chlorate hindered MtBE, EtBE, and TBA degradation.

  3. An ex situ evaluation of TBA- and MTBE-baited bio-traps.

    Science.gov (United States)

    North, Katharine P; Mackay, Douglas M; Annable, Michael D; Sublette, Kerry L; Davis, Greg; Holland, Reef B; Petersen, Daniel; Scow, Kate M

    2012-08-01

    Aquifer microbial communities can be investigated using Bio-traps(®) ("bio-traps"), passive samplers containing Bio-Sep(®) beads ("bio-beads") that are deployed in monitoring wells to be colonized by bacteria delivered via groundwater flow through the well. When bio-beads are "baited" with organic contaminants enriched in (13)C, stable isotope probing allows assessment of the composition and activity of the microbial community. This study used an ex situ system fed by groundwater continuously extracted from an adjacent monitoring well within an experimentally-created aerobic zone treating a tert-butyl alcohol (TBA) plume. The goal was to evaluate aspects of bio-trap performance that cannot be studied quantitatively in situ. The measured groundwater flow through a bio-trap housing suggests that such traps might typically "sample" about 1.8 L per month. The desorption of TBA or methyl tert-butyl ether (MTBE) bait from bio-traps during a typical deployment duration of 6 weeks was approximately 90% and 45%, respectively, of the total initial bait load, with initially high rate of mass loss that decreased markedly after a few days. The concentration of TBA in groundwater flowing by the TBA-baited bio-beads was estimated to be as high as 3400 mg/L during the first few days, which would be expected to inhibit growth of TBA-degrading microbes. Initial inhibition was also implied for the MTBE-baited bio-trap, but at lower concentrations and for a shorter time. After a few days, concentrations in groundwater flowing through the bio-traps dropped below inhibitory concentrations but remained 4-5 orders of magnitude higher than TBA or MTBE concentrations within the aquifer at the experimental site. Desorption from the bio-beads during ex situ deployment occurred at first as predicted by prior sorption analyses of bio-beads but with apparent hysteresis thereafter, possibly due to mass transfer limitations caused by colonizing microbes. These results suggest that TBA- or MTBE

  4. Innovative reactive distillation process for the production of the MTBE substitute isooctane from isobutene

    Energy Technology Data Exchange (ETDEWEB)

    Chalakova, M. [Magdeburg Univ. (Germany). Process Systems Engineering; Kaur, R.; Mahajani, S. [Indian Inst. of Technology, Mumbai (India); Freund, H. [Max-Planck-Institute for Dynamics of Complex Technical Systems, Magdeburg (Germany); Sundmacher, K. [Magdeburg Univ. (Germany). Process Systems Engineering]|[Max-Planck-Institute for Dynamics of Complex Technical Systems, Magdeburg (Germany)

    2007-07-01

    Isooctane is a promising candidate to replace MTBE as gasoline additive if it can be produced in economically and environmentally efficient processes. A promising reaction way at mild conditions is the so called indirect alkylation of isobutene (IB). In the present work two innovative reactive distillation (RD) concepts where the reactions are carried out either simultaneously (fully integrated) or sequentially (partially integrated) are designed. Suitable operation conditions are identified and a comparison with the conventional process scheme under performance and economic aspects is carried out. (orig.)

  5. An ex situ evaluation of TBA- and MTBE-baited bio-traps

    Science.gov (United States)

    North, Katharine P.; Mackay, Douglas M.; Annable, Michael D.; Sublette, Kerry L.; Davis, Greg; Holland, Reef B.; Petersen, Daniel; Scow, Kate M.

    2013-01-01

    Aquifer microbial communities can be investigated using Bio-traps® (“bio-traps”), passive samplers containing Bio-Sep® beads (“bio-beads”) that are deployed in monitoring wells to be colonized by bacteria delivered via groundwater flow through the well. When bio-beads are “baited” with organic contaminants enriched in 13C, stable isotope probing allows assessment of the composition and activity of the microbial community. This study used an ex situ system fed by groundwater continuously extracted from an adjacent monitoring well within an experimentally-created aerobic zone treating a tert-butyl alcohol (TBA) plume. The goal was to evaluate aspects of bio-trap performance that cannot be studied quantitatively in situ. The measured groundwater flow through a bio-trap housing suggests that such traps might typically “sample” about 1.8 L per month. The desorption of TBA or methyl tert-butyl ether (MTBE) bait from bio-traps during a typical deployment duration of 6 weeks was approximately 90% and 45%, respectively, of the total initial bait load, with initially high rate of mass loss that decreased markedly after a few days. The concentration of TBA in groundwater flowing by the TBA-baited bio-beads was estimated to be as high as 3400 mg/L during the first few days, which would be expected to inhibit growth of TBA-degrading microbes. Initial inhibition was also implied for the MTBE-baited bio-trap, but at lower concentrations and for a shorter time. After a few days, concentrations in groundwater flowing through the bio-traps dropped below inhibitory concentrations but remained 4–5 orders of magnitude higher than TBA or MTBE concentrations within the aquifer at the experimental site. Desorption from the bio-beads during ex situ deployment occurred at first as predicted by prior sorption analyses of bio-beads but with apparent hysteresis thereafter, possibly due to mass transfer limitations caused by colonizing microbes. These results suggest that

  6. Mycobacterium persicum sp. nov., a novel species closely related to Mycobacterium kansasii and Mycobacterium gastri.

    Science.gov (United States)

    Shahraki, Abdolrazagh Hashemi; Trovato, Alberto; Mirsaeidi, Mehdi; Borroni, Emanuele; Heidarieh, Parvin; Hashemzadeh, Mohamad; Shahbazi, Narges; Cirillo, Daniela M; Tortoli, Enrico

    2017-06-01

    Four strains isolated in Iran from pulmonary specimens of unrelated patients are proposed as representative of a novel Mycobacterium species. Similarity, at the phenotypic level, with Mycobacterium kansasii is remarkable with the photochromogenic yellow pigmentation of the colonies being the salient feature. They differ, however, genotypically from this species and present unique sequences in 16S rRNA, hsp65 and rpoB genes. The average nucleotide identity and the genome-to-genome distance fully support the status of an independent species. The name proposed for this species is Mycobacterium persicum sp. nov. with AFPC-000227T (=DSM 104278T=CIP 111197T) as the type strain.

  7. Simulation of methyl tert-butyl ether (MTBE) transport to ground water from immobile sources of gasoline in the vadose zone

    Science.gov (United States)

    Lahvis, M.A.; Rehmann, L.C.

    1999-01-01

    The mathematical model, R-UNSAT, developed to simulate the transport of benzene and MTBE in representative sand and clay hydrogeologic systems was evaluated. The effects on groundwater were simulated for small, chronic-, and single-volume releases of gasoline trapped in unsaturated soil. Hydrocarbon biodegradation was simulated by using a dual Monod-type kinetics model that includes oxygen and the reactive constituents. MTBE was assumed to be non-reactive. For MTBE, infiltration had the greatest effect on transport to groundwater. Infiltration also affected mass losses of MTBE to the atmosphere, particularly, in fine-grained soils. Depth to groundwater and soil type primarily affected travel times of MTBE to groundwater, but could affect mass-loading rates to groundwater if infiltration is insignificant. For benzene, transport to groundwater was significant only if the depth to the water table was groundwater were generally smaller for benzene than for MTBE by more than two orders of magnitude. Thus, water that recharges an aquifer beneath a spill can be enriched in MTBE relative to benzene when compared to the composition of water in equilibrium with gasoline.

  8. Calcifications valvulaires chez l'hémodialysé au Maroc | Faqih | Pan ...

    African Journals Online (AJOL)

    Calcifications valvulaires chez l'hémodialysé au Maroc. Samia Ait Faqih, Béfa Noto-Kadou-Kaza, Lalla Meryam Abouamrane, Naoufal Mtiou, Selma El Khaya, Mohamed Zamd, Ghislaine Medkouri, Mohamed Gharbi Bengahanem, Benyounes Ramdani ...

  9. Maintien de l'abstinence chez les patients alcoolo-dependants ...

    African Journals Online (AJOL)

    Maintien de l'abstinence chez les patients alcoolo-dependants: étude comparee de la disponibilite et du cout du traitement par le baclofene, l'acamprosate, et la naltrexone a Cotonou (Benin) et a Lome (Togo)

  10. Mycobacterium ulcerans disease, Peru.

    Science.gov (United States)

    Guerra, Humberto; Palomino, Juan Carlos; Falconí, Eduardo; Bravo, Francisco; Donaires, Ninoska; Van Marck, Eric; Portaels, Françoise

    2008-03-01

    Eight adult patients (ages 18-58, 5 women) with Buruli ulcer (BU) confirmed by at least 2 diagnostic methods were seen in a 10-year period. Attempts to culture Mycobacterium ulcerans failed. Five patients came from jungle areas, and 3 from the swampy northern coast of Peru. The patients had 1-5 lesions, most of which were on the lower extremities. One patient had 5 clustered gluteal lesions; another patient had 2 lesions on a finger. Three patients were lost to follow-up. All 5 remaining patients had moderate disease. Diverse treatments (antituberculous drugs, World Health Organization [WHO] recommended antimicrobial drug treatment for BU, and for 3 patients, excision surgery) were successful. Only 1 patient (patient 7) received the specific drug treatment recommended by WHO. BU is endemic in Peru, although apparently infrequent. Education of populations and training of health workers are first needed to evaluate and understand the full extent of BU in Peru.

  11. Mycobacterium tuberculosis Metabolism

    Science.gov (United States)

    Warner, Digby F.

    2015-01-01

    Metabolism underpins the physiology and pathogenesis of Mycobacterium tuberculosis. However, although experimental mycobacteriology has provided key insights into the metabolic pathways that are essential for survival and pathogenesis, determining the metabolic status of bacilli during different stages of infection and in different cellular compartments remains challenging. Recent advances—in particular, the development of systems biology tools such as metabolomics—have enabled key insights into the biochemical state of M. tuberculosis in experimental models of infection. In addition, their use to elucidate mechanisms of action of new and existing antituberculosis drugs is critical for the development of improved interventions to counter tuberculosis. This review provides a broad summary of mycobacterial metabolism, highlighting the adaptation of M. tuberculosis as specialist human pathogen, and discusses recent insights into the strategies used by the host and infecting bacillus to influence the outcomes of the host–pathogen interaction through modulation of metabolic functions. PMID:25502746

  12. Recherche et Titrage des Hémolysines Anti-A et Anti-B Chez Les ...

    African Journals Online (AJOL)

    Les hémolysines apparaissent suite à une immunisation ABO et peuvent causer, à titre élevé, une hémolyse chez le receveur de sang ou chez le nouveau-né. ... Mots Clés: Hémolysines anti-A et anti-A, Incompatibilité foeto-maternelle ABO, Maladie hémolytique du nouveau-né, Période du post-partum immédiate ...

  13. Caractéristiques épidémiologiques du cancer de la vessie chez la ...

    African Journals Online (AJOL)

    Le tabagisme était retrouvé chez 29,6 % des patientes,l'exposition professionnelle aux carcinogènes dans 5.4 % des cas. Discussion: L'incidence du cancer de la vessie chez la femme est parmi les plus basses dans le monde. Elle est plus élevée dans le grand Tunis et les zones côtières. Elle augmente directement avec ...

  14. Les infections urinaires chez les patients insuffisants rénaux ...

    African Journals Online (AJOL)

    L'infection urinaire chez l'insuffisant rénal est fréquente et particulière dans sa prise en charge diagnostique et thérapeutique. L'objectif de notre étude est de déterminer le profil bactériologique et d'étudier les facteurs de risque des infections urinaires chez le patient insuffisant rénal chronique en milieu de néphrologie.

  15. Odour and flavour thresholds of gasoline additives (MTBE, ETBE and TAME) and their occurrence in Dutch drinking water collection areas

    NARCIS (Netherlands)

    van Wezel, A.; Puijker, L.; Vink, C.; Versteegh, A.; de Voogt, P.

    2009-01-01

    The use of ETBE (ethyl-tert-butylether) as gasoline additive has recently grown rapidly. Contamination of aquatic systems is well documented for MTBE (methyl-tert-butylether), but less for other gasoline additives. Due to their mobility they may easily reach drinking water collection areas. Odour

  16. Modeling the competitive effect of ammonium oxidizers and heterotrophs on the degradation of MTBE in a packed bed reactor

    DEFF Research Database (Denmark)

    Waul, Christopher Kevin; Arvin, Erik; Schmidt, Jens Ejbye

    2008-01-01

    A mathematical model was used to study effects on the degradation of methyl tert-butyl ether (MTBE) in a packed bed reactor due to the presence of contaminants such as ammonium, and the mix of benzene, toluene, ethylbenzene and xylenes (BTEX). It was shown that competition between the slower...

  17. ANAEROBIC DEGRADATION OF MTBE TO TBA IN GROUND WATER AT GASOLINE SPILL SITES IN ORANGE COUNTY, CALIFORNIA

    Science.gov (United States)

    Although tert-Butyl Alcohol (TBA) has not been used as a fuel oxygenate in Orange County, California, the concentrations of TBA in ground water at gasoline spill sites are high compared to the concentrations of the conventional fuel oxygenate Methyl tert-Butyl Ether (MTBE). In t...

  18. Fenton-driven regeneration of MTBE-spent granular activated carbon - Effects of particle size and Iron Amendment Procedures

    Science.gov (United States)

    Fenton-driven regeneration of spent granular activated carbon (GAC) is a technology being developed to regenerate organic contaminant-spent GAC. Here, the effect of GAC particle size (>2 mm to <0.35 mm) on Fenton-driven oxidation of methyl tert-butyl ether (MTBE)-spent GAC was ev...

  19. Effects on temperature and acidic pre-treatment on Fenton-driven oxidation of MTBE-spent granular activated carbon

    Science.gov (United States)

    Temperature-dependent mechanisms in the Fenton-driven chemical oxidation of methyl tert-butyl ether (MTBE)-spent granular activated carbon (GAC) was investigated. Prior to iron (Fe) amendment to the GAC, acid-treatment altered the surface chemistry of the GAC and lowered the p...

  20. Effects of Temperature and Acidic Pre-Treatment on Fenton-Driven Oxidation of MTBE-Spent Granular Activated Carbon

    Science.gov (United States)

    Temperature-dependent mechanisms in the Fenton-driven chemical oxidation of methyl tert-butyl ether (MTBE)-spent granular activated carbon (GAC) was investigated. Prior to iron (Fe) amendment to the GAC, acid-treatment altered the surface chemistry of the GAC and lowered the pH ...

  1. Anaerobic degradation of a mixture of MtBE, EtBE, TBA, and benzene under different redox conditions

    NARCIS (Netherlands)

    Waals, van der Marcelle J.; Pijls, Charles; Sinke, Anja J.C.; Langenhoff, Alette A.M.; Smidt, Hauke; Gerritse, Jan

    2018-01-01

    The increasing use of biobased fuels and fuel additives can potentially change the typical fuel-related contamination in soil and groundwater. Anaerobic biotransformation of the biofuel additive ethyl tert-butyl ether (EtBE), as well as of methyl tert-butyl ether (MtBE), benzene, and tert-butyl

  2. TOXICITY OF METHYL-TERT BYTYL ETHER (MTBE) TO PLANTS (AVENA SATIVA, ZEA MAYS, TRITICUM AESTIVUM, AND LACTUCA SATIVA)

    Science.gov (United States)

    Effects of Methyl tert-butyl ether (MTBE) on the germination of seeds and growth of the plant were studied in some laboratory experiments. Test plants were wild oat (Avena sative), sweet corn (Zea mays), wheat (Triticum aestivum), and lettuce (Lactuca sativa). Seed germination,...

  3. MTBE DEGRADATION USING FENTON'S REAGENT: THE EFFECT OF FERROUS AND FERRIC IRON MIXTURES ON THE EFFICIENCY OF THE OVERALL REACTION

    Science.gov (United States)

    The gasoline additive MTBE has been extensively used in the U.S. since the late 70's to increase the octane rating in reformulated gasoline, replacing toxic organo-lead compounds. However, its use was boosted during the late 80's, when the study of additional physico-chemical pro...

  4. Fenton-driven regeneration of MTBE-spent granular activated carbon - Effects of particle size and Iron Amendment Procedures

    Science.gov (United States)

    Fenton-driven regeneration of spent granular activated carbon (GAC) is a technology being developed to regenerate organic contaminant-spent GAC. Here, the effect of GAC particle size (>2 mm to Fenton-driven oxidation of methyl tert-butyl ether (MTBE)-spent GAC was ev...

  5. Modeling Of A Reactive Distillation Column: Methyl Tertiary Butyl Ether (Mtbe Simulation Studies

    Directory of Open Access Journals (Sweden)

    Ismail Mohd Saaid Abdul Rahman Mohamed and Subhash Bhatia

    2012-10-01

    Full Text Available A process simulation stage-wise reactive distillation column model formulated from equilibrium stage theory was developed. The algorithm for solving mathematical model represented by sets of differential-algebraic equations was based on relaxation method. Numerical integration scheme based on backward differentiation formula was selected for solving the stiffness of differential-algebraic equations. Simulations were performed on a personal computer (PC Pentium processor through a developed computer program using FORTRAN90 programming language. The proposed model was validated by comparing the simulated results with the published simulation results and with the pilot plant data from the literature. The model was capable of predicting high isobutene conversion for heterogeneous system, as desirable in industrial MTBE production process. The comparisons on temperature profiles, liquid composition profile and operating conditions of reactive distillation column also showed promising results. Therefore the proposed model can be used as a tool for the development and simulation of reactive distillation column.Keywords: Modeling, simulation, reactive distillation, relaxation method, equilibrium stage, heterogeneous, MTBE

  6. MTBE and priority contaminant treatment with high energy electron beam injection

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, William J; Nickelsen, Michael G; Mezyk, Stephen P; Leslie, Greg; Tornatore, Paul M; Hardison, Wayne; Hajali, Paris A

    2002-11-01

    A study was conducted to examine the removal of methyl tert-butyl ether (MTBE) and 15 other organic compounds, as well as perchlorate ion, in waters of different quality. The 15 organic compounds consisted of halogenated solvents (chlorination), disinfection by-products, pesticides, and nitrosodimethylamine (NDMA). These studies were conducted using a pilot scale 20 kW mobile electron beam system at Water Factory 21, Orange County, CA where wastewater is treated and re-injected into the ground as a barrier to salt water intrusion. Future applications for this treated water include water reuse. Ground water and treated wastewater, after having gone through a reverse osmosis-polishing step (RO permeate), were used to prepare mixtures of the compounds. Using fundamental radiation chemistry, it was possible to examine the factors effecting removal efficiency of all the compounds as well as MTBE destruction and reaction by-product formation and removal. All of the organic compounds were destroyed in the studies and we also observed the destruction of perchlorate ion in one of the waters.

  7. MTBE and priority contaminant treatment with high energy electron beam injection

    International Nuclear Information System (INIS)

    Cooper, William J.; Nickelsen, Michael G.; Mezyk, Stephen P.; Leslie, Greg; Tornatore, Paul M.; Hardison, Wayne; Hajali, Paris A.

    2002-01-01

    A study was conducted to examine the removal of methyl tert-butyl ether (MTBE) and 15 other organic compounds, as well as perchlorate ion, in waters of different quality. The 15 organic compounds consisted of halogenated solvents (chlorination), disinfection by-products, pesticides, and nitrosodimethylamine (NDMA). These studies were conducted using a pilot scale 20 kW mobile electron beam system at Water Factory 21, Orange County, CA where wastewater is treated and re-injected into the ground as a barrier to salt water intrusion. Future applications for this treated water include water reuse. Ground water and treated wastewater, after having gone through a reverse osmosis-polishing step (RO permeate), were used to prepare mixtures of the compounds. Using fundamental radiation chemistry, it was possible to examine the factors effecting removal efficiency of all the compounds as well as MTBE destruction and reaction by-product formation and removal. All of the organic compounds were destroyed in the studies and we also observed the destruction of perchlorate ion in one of the waters

  8. Intrinsic bioremediation of a BTEX and MTBE plume under mixed aerobic/denitrifying conditions

    International Nuclear Information System (INIS)

    Borden, R.C.; Daniel, R.A.

    1995-01-01

    A shallow Coastal Plain aquifer in rural Sampson Country, North Carolina, has been contaminated with petroleum hydrocarbon from a leaking underground storage tank containing gasoline.An extensive field characterization has been performed to define the horizontal and vertical distribution of soluble gasoline components and indicator parameters. A plume of dissolved methyl tert-butyl ether (MTBE) and the aromatic hydrocarbons benzene, toluene, ethylbenzene, and xylene isomers (BTEX) is present in the aquifer and has migrated over 600 ft from the source area. Background dissolved oxygen concentrations range from 7 to 8 mg/L, and nitrate concentrations range from 5 to 22 mg/L as N due to extensive fertilization of fields surrounding the spill. In the center of the BTEX plume, oxygen concentrations decline to less than 1 mg/L while nitrate concentrations remain high. The total mass flux of MTBE and all BTEX components decline with distance downgradient relative to a conservative tracer (chloride). At the source, the total BTEX concentration exceeds 75 mg/L while 130 ft downgradient, total BTEX concentrations are less than 4.9 mg/L, a 15-fold reduction. Toluene and ethylbenzene decline most rapidly followed by m-p-xylene, o-xylene and finally benzene. Biodegradation of TEX appears to be enhanced by the excess nitrate present in the aquifer while benzene biodegradation appears to be due to strictly aerobic processes

  9. Adsorption of BTEX, MTBE and TAME on natural and modified diatomite.

    Science.gov (United States)

    Aivalioti, Maria; Papoulias, Panagiotis; Kousaiti, Athanasia; Gidarakos, Evangelos

    2012-03-15

    The removal of BTEX (benzene, toluene, ethyl-benzene and m-,p-,o-xylenes), MTBE (methyl tertiary butyl ether) and TAME (tertiary amyl methyl ether) from aqueous solutions by raw, thermally, chemically and both chemically and thermally treated diatomite was studied, through batch adsorption experiments. In total, 14 different diatomite samples were created and tested. Selected physical characteristics of the adsorbents, such as specific surface area and pore volume distribution, were determined. Matrix and competitive adsorption effects were also explored. It was proved that the diatomite samples were effective in removing BTEX, MTBE and TAME from aqueous solutions, with the sample treated with HCl being the most effective, as far as its adsorption capacity and equilibrium time are concerned. Among the contaminants, BTEX appeared to have the strongest affinity, based on mass uptake by the diatomite samples. Matrix effects were proved to be strong, significantly decreasing the adsorption of the contaminants onto diatomite. The kinetics data proved a closer fit to the pseudo second order model, while the isotherm experimental data were a better fit to the Freundlich model. However, the latter produced values of the isotherm constant 1/n greater than one, indicating unfavorable adsorption. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Bases chimiosensorielles du comportement alimentaire chez les poissons

    OpenAIRE

    Saglio, P.

    1981-01-01

    Le comportement alimentaire, indispensable à la survie de l'individu et donc de l'espèce, occupe à ce titre une position de première importance dans la hiérarchie des comportements fondamentaux qui tous en dépendent très étroitement. Chez les poissons, cette prééminence se trouve illustrée par l'extrême diversité des supports sensoriels impliqués et des expressions comportementales qui leur sont liées. A la suite d'un certain nombre de mises en évidence neurophysiologiques et éthologiques de ...

  11. Mycobacterium fortuitum causing surgical site wound infection

    International Nuclear Information System (INIS)

    Kaleem, F.; Usman, J.; Omair, M.; Din, R.U.; Hassan, A.

    2010-01-01

    Mycobacterium fortuitum, a rapidly growing mycobacterium, is ubiquitous in nature. The organism was considered to be a harmless saprophyte but now there have been several reports from different parts of the world wherein it has been incriminated in a variety of human infections. We report a culture positive case of surgical site infection caused by Mycobacterium fortuitum, who responded well to the treatment. (author)

  12. Les jeux de hasard chez les enfants et les adolescents

    Science.gov (United States)

    Gupta, Rina; Pinzon, Jorge L

    2012-01-01

    RÉSUMÉ Même si, au Canada, les mineurs n’ont pas le droit de jouer à des jeux de hasard légalisés, les adolescents participent souvent à des jeux de hasard soit légalisés (produits de loterie, casino, terminaux de jeux vidéo), soit autonomes (jeux de cartes, paris sportifs, dés) à la maison et en milieu scolaire. Chez les adultes, le taux de prévalence de dépendance aux jeux de hasard au cours de la vie se situe entre 1 % et 2 %. D’après les données existantes, la prévalence chez les adolescents serait de deux à quatre fois plus élevée. On ne sait pas grand-chose des facteurs de risque d’apparition et de perpétuation d’une dépendance pathologique aux jeux de hasard. Le présent document de principes vise à informer les pédiatres, les médecins de famille et les autres professionnels de la santé des connaissances émergentes sur les jeux de hasard pendant l’enfance et l’adolescence et du risque de conséquences graves qui s’y rattachent. On y exhorte également les gouvernements fédéral, provinciaux et territoriaux à inclure cette question dans leur programme et à tenir compte des facteurs sociopolitiques associés aux jeux de hasard.

  13. Mycobacterium saopaulense sp. nov., a rapidly growing mycobacterium closely related to members of the Mycobacterium chelonae--Mycobacterium abscessus group.

    Science.gov (United States)

    Nogueira, Christiane Lourenço; Whipps, Christopher M; Matsumoto, Cristianne Kayoko; Chimara, Erica; Droz, Sara; Tortoli, Enrico; de Freitas, Denise; Cnockaert, Margo; Palomino, Juan Carlos; Martin, Anandi; Vandamme, Peter; Leão, Sylvia Cardoso

    2015-12-01

    Five isolates of non-pigmented, rapidly growing mycobacteria were isolated from three patients and,in an earlier study, from zebrafish. Phenotypic and molecular tests confirmed that these isolates belong to the Mycobacterium chelonae-Mycobacterium abscessus group, but they could not be confidently assigned to any known species of this group. Phenotypic analysis and biochemical tests were not helpful for distinguishing these isolates from other members of the M. chelonae–M.abscessus group. The isolates presented higher drug resistance in comparison with other members of the group, showing susceptibility only to clarithromycin. The five isolates showed a unique PCR restriction analysis pattern of the hsp65 gene, 100 % similarity in 16S rRNA gene and hsp65 sequences and 1-2 nt differences in rpoB and internal transcribed spacer (ITS) sequences.Phylogenetic analysis of a concatenated dataset including 16S rRNA gene, hsp65, and rpoB sequences from type strains of more closely related species placed the five isolates together, as a distinct lineage from previously described species, suggesting a sister relationship to a group consisting of M. chelonae, Mycobacterium salmoniphilum, Mycobacterium franklinii and Mycobacterium immunogenum. DNA–DNA hybridization values .70 % confirmed that the five isolates belong to the same species, while values ,70 % between one of the isolates and the type strains of M. chelonae and M. abscessus confirmed that the isolates belong to a distinct species. The polyphasic characterization of these isolates, supported by DNA–DNA hybridization results,demonstrated that they share characteristics with M. chelonae–M. abscessus members, butconstitute a different species, for which the name Mycobacterium saopaulense sp. nov. is proposed. The type strain is EPM10906T (5CCUG 66554T5LMG 28586T5INCQS 0733T).

  14. Buruli Ulcer (Mycobacterium ulcerans Infection)

    Science.gov (United States)

    ... detail/buruli-ulcer-(mycobacterium-ulcerans-infection)","@context":"http://schema.org","@type":"Article"}; العربية 中文 français русский español ... Buruli ulcer on a regular basis to share information, coordinate disease control and research efforts, and monitor ...

  15. Characterization of a Mycobacterium leprae antigen related to the secreted Mycobacterium tuberculosis protein MPT32

    NARCIS (Netherlands)

    Wieles, B.; van Agterveld, M.; Janson, A.; Clark-Curtiss, J.; Rinke de Wit, T.; Harboe, M.; Thole, J.

    1994-01-01

    Secreted proteins may serve as major targets in the immune response to mycobacteria. To identify potentially secreted Mycobacterium leprae antigens, antisera specific for culture filtrate proteins of Mycobacterium tuberculosis were used to screen a panel of recombinant antigens selected previously

  16. Methyl tert-Butyl Ether (MTBE) - Its Movement and Fate in the Environment and Potential for Natural Attenuation

    Science.gov (United States)

    1999-10-01

    but at varying rates, by indigenous microbiota . Normal alkanes of low molecular weight (C-8 to C-22) are metabolized most rapidly, followed by...confirmed that TBA degradation occurred at a rate slower than MTBE degradation. Pure bacterial cultures isolated from activated sludge and the fruit of...isolated from activated sludge and fruit of the Gingko tree. They have been classified as belonging to the genuses Methlobacterium, Rhodococcus, and

  17. Liberté et habitus chez Pierre Bourdieu.

    Directory of Open Access Journals (Sweden)

    Mathieu Hilgers

    2006-07-01

    Full Text Available La question de la libert é e st récurrente dans les théories de l’habitus. Bien qu'il en fasse un concept central, elle reste si peu thématisée chez Bourdieu que de nombreux critiques ont pu taxer son travail de déterministe. Pourtant, une lecture approfondie permet de dégager au cœur du modèle au moins trois principes qui le rendent incompatible avec le déterminisme : la production d’un nombre infini de comportements à partir d’un nombre limité de principes, la mutation permanente et les limites intensives et extensives de l’appréhension sociologique. L’identification de ses principes et l’analyse de leur portée sur la matrice conceptuelle permettent de mieux comprendre le statut de la liberté dans l’œuvre de Bourdieu. The question of freedom is recurrent in the theories of habitus. In the Bourdieu’s work, the freedom plays an essential role but not often explicit. This article tries to identify and to analyse the underlying principles of the freedom in this sociological approach.

  18. Intoxications aigues aux organophosphores chez la femme enceinte

    Science.gov (United States)

    Barhoumi, Mohamed Hafed; Bannour, Badra; Barhoumi, Tarek; Jouini, Rami; Marwene, Nadia; Fatnassi, Mohamed Ridha

    2016-01-01

    Les intoxications aiguës par les pesticides organophosphorés (OP) au cours de la grossesse sont des événements rares, peu décrites dans la littérature. A travers cette étude rétrospective, nous rapportons les résultats de sept cas d’ingestion suicidaire d’OP chez des femmes enceintes. Cette intoxication était le plus souvent grave. En effet, cinq des sept parturientes avaient un Glasgow initial des cas elle était défavorable pour le fœtus (mort fœtal in utéro). Deux mécanismes peuvent expliquer ces complications fœtales. Le premier est l’hypoxie fœtale associée ou non à un état de choc qui peuvent se traduire au niveau du RCF par une tachycardie ou des décélérations et aboutir ainsi à un décès in utero. Le deuxième mécanisme est le passage de ces pesticides à travers la barrière placentaire, ce qui pose un risque potentiel pour le fœtus par altération des systèmes enzymatiques des microsomes. PMID:28293343

  19. Effect of benzene, toluene, ethylbenzene, and p-xylene (BTEX) mixture on biodegradation of methyl tert-butyl ether (MTBE) and tert-butyl alcohol (TBA) by pure culture UC1.

    Science.gov (United States)

    Pruden, Amy; Suidan, Makram

    2004-08-01

    The effect of a BTEX mixture on the biodegradation of methyl tert-butyl ether (MTBE) and its degradation intermediate, tert-butyl alcohol (TBA) was investigated in the pure bacterial culture UC1, which has been identified to be a strain of the known MTBE-degrader PM1 based on greater than 99% 16S rDNA similarity. Several degradation studies were carried out on UC1 at three initial concentration levels of MTBE or TBA: 6-7; 15-17; and 40-45 mg/l, both with and without BTEX present cumulatively at about half of the MTBE or TBA molar mass in the system. The BTEX mixture was observed not to affect either the rate or the degradation lag period of MTBE or TBA degradation, except that the TBA degradation rate actually increased when BTEX was present initially in the highest concentration studies. When serving as the sole substrate, the MTBE degradation rate ranged from 48 +/- 1.2 to 200 +/- 7.0 mg(MTBE)/g(dw) h, and the TBA degradation rate from 140 +/- 18 to 530 +/- 70 mg(TBA)/g(dw) h. When present with BTEX, MTBE and TBA rates ranged from 46 +/- 2.2 to 210 +/- 14 and 170 +/- 28 to 780 +/- 43 mg(TBA)/g(dw) h, respectively. In studies where varying concentrations of TBA were present with 5 mg/l MTBE, both compounds were degraded simultaneously with no obvious preference for either substrate. In the highest concentration study of TBA with 5 mg/l MTBE, BTEX was also observed to increase the ultimate rate of TBA degradation. In addition to exploring the affect of BTEX, this study also provides general insight into the metabolism of MTBE and TBA by pure culture UC1.

  20. Bio-MTBE. How to reduce CO{sub 2} footprint in fuels with a well known premium gasoline component

    Energy Technology Data Exchange (ETDEWEB)

    Busch, O.; Schade, A.; Rasch, H.; Schulte-Koerne, E. [Evonik Industries AG, Marl (Germany)

    2012-07-01

    With the revision of Renewable Energy Directive (RED) and Fuels Quality Directive (FQD) in 2009 the EU Commission promoted the use of biofuels, especially of those made from residues and waste because of their favourable CO{sub 2} footprint. Crude glycerol is an inevitable residue of conventional biodiesel production and can therefore be used to make 2{sup nd} generation biofuels, in this case bio-methanol. Methanol itself has several application issues as a fuel and can only be blended into gasoline at low quantities (max. 3 vol.-% according to European gasoline specification EN 228). However, today methanol is virtually absent in European gasoline due to its detrimental properties (e.g. corrosivity, water miscibility, etc.). In contrast to this, MTBE (methyl tertiary butyl ether) made from methanol and isobutylene is a high value gasoline component that can be blended into gasoline at high quantities without any application issues. Current European gasoline specification allows up to 15 vol.-%% and the revised FQD has enabled the specification to be expanded to up to 22 vol.-% MTBE in gasoline. Thus, bio-methanol converted into bio-MTBE is an appropriate pathway to get a 2{sup nd} generation biofuel into the blending pool with perfect compatibility with infrastructure and the existing car fleet. (orig.)

  1. Sludge Recycle of Wastewater Treatment Plant via its Application as Powdered Activated Carbon for Removal of Methyl Tertiary-Butyl Ether (MTBE from Aqueous Solutions

    Directory of Open Access Journals (Sweden)

    MR Zare

    2016-05-01

    Full Text Available Introduction: Nowadays, application of MTBE due to its physical and chemical characteristics including high solubility in water has been increased, resulting in its release into the water resources. On other hand, waste activated sludge derived from municipal wastewater treatment plant (MWTP contains high amount of carbon. Therefore, this study aimed to provide the activated carbon via sludge of MWTP as well as to evaluate its efficiency for MTBE removal. Methods: The effect of some parameters such as kind of activator, pH (2-10, contact time (0-240min, adsorbent dose (2-6g/L and initial concentration of MTBE (20-70mg/L was investigated on MTBE adsorption via activated carbon, after preparation of coal from wastewater sludge and activation of this coal via 3 molar solution of H2PO4,  and KOH as well as 5 molar solution of ZnCl2. MTBE concentration in solution was determined via Gas-Chromatography instrument. The obtained experimental data were modeled by adsorption model of Freundlich and Langmuir. Results: The maximum adsorbed MTBE per gram of activated carbon was obtained when the ZnCL2 was used as an activator; however, there was no statistically significant difference among different activators. In addition, maximum removal efficiency (about 50% was obtained in acidic pH of 4, 6g/L of activated carbon and 20mg/L of MTBE concentration. Results of adsorption isotherm showed that Freundlich adsorption model had a better compliance with the experimental data. Conclusion: Regarding the problems associated with sludge disposal of wastewater treatment plant, recycling of this sludge, as an adsorbent, can eliminate most of these problems. As a result, the economical features with respect to industrial scale application and the efficiency of this substance in removal of other pollutants are recommended to be investigated.

  2. Polymorphisms of twenty regulatory proteins between Mycobacterium tuberculosis and Mycobacterium bovis

    Science.gov (United States)

    Mycobacterium tuberculosis and Mycobacterium bovis are responsible for tuberculosis in humans or animals, respectively. Both species are closely related and belong to the Mycobacterium tuberculosis complex (MTC). M. tuberculosis is the most ancient species from which M. bovis and the other members o...

  3. Gradients socioéconomiques du risque cardiovasculaire chez les enfants et les adolescents canadiens

    Directory of Open Access Journals (Sweden)

    Y. Shi

    2016-01-01

    Full Text Available Introduction : Les maladies cardiovasculaires (MCV et leurs facteurs de risque présentent des gradients socioéconomiques clairs chez les adultes canadiens, mais présentent des ambiguïtés chez les enfants. L'objectif de cette étude est de vérifier l'existence ou non de gradients socioéconomiques dans les marqueurs physiologiques du risque de MCV chez les enfants et les adolescents canadiens. Méthodologie : À partir des données transversales combinées de l'Enquête canadienne sur les mesures de la santé 2007-2011, nous avons étudié, chez 2 149 enfants (6 à 11 ans et 2 073 adolescents (12 à 17 ans et selon le sexe, les marqueurs de risque cardiovasculaire suivants : excès de poids (y compris l'obésité, score de capacité aérobique (SCA, pression artérielle (PA, lipides sanguins (totaux, cholestérol LDL et HDL, triglycérides, métabolisme du glucose et protéine C réactive (CRP. Des analyses de régression logistique et de régression linéaire multidimensionnelles ont permis de dégager les tendances relatives au risque cardiovasculaire en fonction de la suffisance du revenu du ménage et du niveau de scolarité des parents, après ajustement en fonction de l'âge et de l'origine ethnique, et après stratification par groupe d'âge et par sexe. Résultats : La prévalence de l'obésité était sensiblement plus élevée chez les jeunes garçons que chez les jeunes filles (prévalence de 18,5 %, intervalle de confiance [IC] à 95 % : 15,6 à 21,5 contre 7,7 %, IC à 95 % : 5,2 à 10,3. Toutefois, des gradients socioéconomiques négatifs ont été observés en ce qui concerne le risque d'adiposité chez les jeunes filles et les adolescentes, et non chez les garçons. Parmi les enfants et les adolescents, les garçons étaient en meilleure condition physique que les filles (SCA moyen de 541, IC à 95 % : 534 à 546 contre 501, IC à 95 % : 498 à 505 chez les enfants; 522, IC à 95 % : 514 à 529 contre 460, IC à 95 % : 454

  4. Mycobacterium avium Infection after Acupoint Embedding Therapy

    Directory of Open Access Journals (Sweden)

    Jiao Zhang, MD

    2017-09-01

    Full Text Available Summary:. Nontuberculous mycobacterium is a ubiquitous environmental organism that is unusual to cause a true infection, but it can cause severe cutaneous infections. In this case report, we present a successful treatment for a Chinese patient with Mycobacterium avium cutaneous infection after acupoint embedding therapy. We managed to conduct pathogenic detection, drug sensitive test, and multidisciplinary consultation. Finally, a systematic treatment strategy of nontuberculous mycobacterium was performed. Twenty-two-month follow-up revealed excellent outcome without any recurrence.

  5. The Chemistry and Flow Dynamics of Molecular Biological Tools Used to Confirm In Situ Bioremediation of Benzene, TBA, and MTBE

    Science.gov (United States)

    North, K. P.; Mackay, D. M.; Scow, K. M.

    2010-12-01

    In situ bioremediation has typically been confirmed by collecting sediment and groundwater samples to directly demonstrate a degradation process in a laboratory microcosm. However, recent advances in molecular biological tools present options for demonstrating degradation processes with field-based tools that are less time-consuming. We have been investigating the capability of some of these molecular biological tools to evaluate in situ biodegradation of tert-butyl alcohol (TBA), methyl tert-butyl ether (MTBE), and benzene at two field sites in California. At both sites, we have deployed Bio-Traps® (“traps”), made of Bio-Sep® beads in slotted PVC pipe, which provide ideal environments for microbial colonization. Stable Isotope Probing can be accomplished by sorbing the13C-labeled organic contaminant of concern onto Bio-Sep® beads (“baiting”); incorporation of 13C into the biomass collected by the trap would indicate that the microbial community was capable of degrading the labeled compound. In addition, we examined the chemistry and flow dynamics of these traps and present those results here. We performed a field experiment and a lab experiment to, in part, define the rate that different baits leached off various traps. At a TBA- and MTBE-contaminated site at Vandenberg AFB, Lompoc, CA, the TBA-dominant plume was effectively treated by recirculation/oxygenation of groundwater, decreasing TBA and MTBE concentrations to detection limits along predicted flowpaths created by two pairs of recirculation wells. We used the generated aerobic treatment zone to deploy traps baited with 13C-labeled MTBE or TBA in a novel, ex situ experimental setup. The groundwater flow extracted from the aerobic treatment zone was split through several chambers, each containing a trap and monitoring of influent and effluent. The chamber effluent was measured throughout a six-week deployment and analyzed for both TBA and MTBE; the majority of mass leached from the baited traps did

  6. γ-aminobutyric acidA (GABAA) receptor regulates ERK1/2 phosphorylation in rat hippocampus in high doses of Methyl Tert-Butyl Ether (MTBE)-induced impairment of spatial memory

    International Nuclear Information System (INIS)

    Zheng Gang; Zhang Wenbin; Zhang Yun; Chen Yaoming; Liu Mingchao; Yao Ting; Yang Yanxia; Zhao Fang; Li Jingxia; Huang Chuanshu; Luo Wenjing; Chen Jingyuan

    2009-01-01

    Experimental and occupational exposure to Methyl Tert-Butyl Ether (MTBE) has been reported to induce neurotoxicological and neurobehavioral effects, such as headache, nausea, dizziness, and disorientation, etc. However, the molecular mechanisms involved in MTBE-induced neurotoxicity are still not well understood. In the present study, we investigated the effects of MTBE on spatial memory and the expression and function of GABA A receptor in the hippocampus. Our results demonstrated that intraventricular injection of MTBE impaired the performance of the rats in a Morris water maze task, and significantly increased the expression of GABA A receptor α1 subunit in the hippocampus. The phosphorylation of ERK1/2 decreased after the MTBE injection. Furthermore, the decreased ability of learning and the reduction of phosphorylated ERK1/2 level of the MTBE-treated rats was partly reversed by bicuculline injected 30 min before the training. These results suggested that MTBE exposure could result in impaired spatial memory. GABA A receptor may play an important role in the MTBE-induced impairment of learning and memory by regulating the phosphorylation of ERK in the hippocampus.

  7. Bases chimiosensorielles du comportement alimentaire chez les poissons

    Directory of Open Access Journals (Sweden)

    SAGLIO Ph.

    1981-07-01

    Full Text Available Le comportement alimentaire, indispensable à la survie de l'individu et donc de l'espèce, occupe à ce titre une position de première importance dans la hiérarchie des comportements fondamentaux qui tous en dépendent très étroitement. Chez les poissons, cette prééminence se trouve illustrée par l'extrême diversité des supports sensoriels impliqués et des expressions comportementales qui leur sont liées. A la suite d'un certain nombre de mises en évidence neurophysiologiques et éthologiques de l'importance du sens chimique (olfaction, gustation dans le comportement alimentaire des poissons, de très importants secteurs d'études électrophysiologiques et d'analyses physico-chimiques visant à en déterminer la nature exacte (en termes de substances actives se sont développés ces vingt dernières années. De tous ces travaux dont les plus avancés sont présentés ici, il ressort que les acides aminés de série L plus ou moins associés à d'autres composés de poids moléculaires < 1000 constituent des composés chimiques jouant un rôle déterminant dans le comportement alimentaire de nombreuses espèces de poissons carnivores.

  8. Mise en évidence d'une variation intra spécifique chez Botrytis ...

    African Journals Online (AJOL)

    SARAH

    25 avr. 2013 ... 2 Présidence de l'Université Ibn Tofaïl, Kenitra, Maroc. Auteur correspondant .... ambiante et sous lumière continue afin de favoriser davantage la .... formation de sclérotes sur les disques foliaires de tomate est observée chez ...

  9. Dépistage sérologique de la maladie coeliaque chez des patients ...

    African Journals Online (AJOL)

    transglutaminase tissulaire (AtTG) et anti-gliadines (AAG) chez les patients diabétiques de type 1 dans le but de recommander une éventuelle biopsie jéjunale et d'instaurer un régime sans gluten précocement avant l'installation des signes ...

  10. La dialyse péritonéale chez les patients de moins de vingt ans ...

    African Journals Online (AJOL)

    La dialyse péritonéale chez les patients de moins de vingt ans: expérience d'un centre hospitalier universitaire marocain. Intissar Haddiya, Hakima Rhou, Fatima Ezaitouni, Naima Ouzeddoun, Rabia Bayahia, Loubna Benamar ...

  11. Les accidents de la vie courante chez l'enfant à Dakar: à propos de ...

    African Journals Online (AJOL)

    Les accidents de la vie courante chez l'enfant à Dakar: à propos de 201 cas. Azhar Salim Mohamed, Aloïse Sagna, Mbaye Fall, Ndeye Aby Ndoye, Papa Alassane Mbaye, Aimé Lakh Fall, Alou Diaby, Oumar Ndour, Gabriel Ngom ...

  12. Les troubles gonadiques chez les hémodialysés chroniques à l ...

    African Journals Online (AJOL)

    étude montre une forte prévalence des manifestations cliniques des troubles gonadiques chez les patients en hémodialyse chronique. Aussi elles doivent être recherchées afin de mieux les prendre en charge, car ces troubles sont vécus par ...

  13. S'attaquer à la marginalisation, à la criminalité et à la violence chez ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    S'attaquer à la marginalisation, à la criminalité et à la violence chez les jeunes - le rôle du capital social communautaire. Il est maintenant reconnu que les adolescents ont besoin d'un capital social positif (réseaux sociaux, relations interpersonnelles) pour devenir des adultes productifs et socialement responsables.

  14. Evolution des paramètres biochimiques chez les chevaux de sport ...

    African Journals Online (AJOL)

    Evolution des paramètres biochimiques chez les chevaux de sport pendant un test d'effort. ... English Title: Evolution of biochemical parameters in sport horses subjected to a stress test. English Abstract. The study aimed ... The evaluation of the fitness of these racehorses is of great use in assessing the physical conditions.

  15. Effects of aromatics, MTBE, olefins, and T90 on urban air quality year 2005/2010

    International Nuclear Information System (INIS)

    Dunker, A.M.; Morris, R.D.; Pollack, A.K.; Cohen, J.P.; Schleyer, C.H.

    1992-01-01

    Subject to the limitations described in the Discussion, changing fuel composition changes the light-duty vehicle contribution to ozone. By the year 2005/2010, light-duty vehicles will contribute only 5 to 9% of the peak ozone in the three cities studied, because large reductions in automotive emissions are projected due to regulations now in place. For the reformulated gasolines studied, the contribution of light-duty vehicles to peak ozone can be reduced up to 26%. Reducing gasoline olefin content reduces ozone formation, due to its impact on evaporative, running-loss, and refueling and storage emissions. Lowering gasoline boiling range also reduces ozone formation by lowering the reactivity of exhaust emissions. Reducing aromatic content or adding MTBE had no clear effect on ozone formation. The emissions inventories used in the air quality modeling contain significant uncertainties. In particular, recent studies have suggested that emissions models may significantly underestimate hydrocarbon and CO emissions from today's vehicle fleet. If this is the case, the predicted ozone reductions due to reformulated gasoline reported here may be underestimated

  16. Molecular Characterization of the Resistance of Mycobacterium ...

    African Journals Online (AJOL)

    Purpose: To characterize the resistance of Mycobacterium tuberculosis to second line drugs using a line probe assay. Methods: Multi-drug resistant strains of Mycobacterium tuberculosis isolated between December 2008 and December 2009 were tested for resistance to fluoroquinolones and second-line injectable drugs ...

  17. Disseminated Mycobacterium avium infection in a cat

    OpenAIRE

    Barry, Maureen; Taylor, Judith; Woods, Paul

    2002-01-01

    A domestic shorthair cat was presented for lethargy and ataxia. Clinical findings included an abdominal mass, lumbosacral pain, ataxia. Aspirates from the liver and lymph nodes revealed intracellular, negative-staining rods. Treatment for presumptive mycobacterium infection was unsuccessful and the cat was euthanized. Disseminated Mycobacterium avium was confirmed on culture.

  18. Disseminated Mycobacterium avium infection in a cat.

    Science.gov (United States)

    Barry, Maureen; Taylor, Judith; Woods, J Paul

    2002-05-01

    A domestic shorthair cat was presented for lethargy and ataxia. Clinical findings included an abdominal mass, lumbosacral pain, ataxia. Aspirates from the liver and lymph nodes revealed intracellular, negative-staining rods. Treatment for presumptive mycobacterium infection was unsuccessful and the cat was euthanized. Disseminated Mycobacterium avium was confirmed on culture.

  19. Drug Resistance of Mycobacterium tuberculosis Complex among ...

    African Journals Online (AJOL)

    BACKGROUND: In Burkina Faso, there is no recent data about the level of drug resistance in Mycobacterium tuberculosis strains among newly diagnosed tuberculosis cases. OBJECTIVE: To provide an update of the primary drug resistance of mycobacterium tuberculosis among patients in Burkina faso. METHODS: ...

  20. MycoCAP - Mycobacterium Comparative Analysis Platform.

    Science.gov (United States)

    Choo, Siew Woh; Ang, Mia Yang; Dutta, Avirup; Tan, Shi Yang; Siow, Cheuk Chuen; Heydari, Hamed; Mutha, Naresh V R; Wee, Wei Yee; Wong, Guat Jah

    2015-12-15

    Mycobacterium spp. are renowned for being the causative agent of diseases like leprosy, Buruli ulcer and tuberculosis in human beings. With more and more mycobacterial genomes being sequenced, any knowledge generated from comparative genomic analysis would provide better insights into the biology, evolution, phylogeny and pathogenicity of this genus, thus helping in better management of diseases caused by Mycobacterium spp.With this motivation, we constructed MycoCAP, a new comparative analysis platform dedicated to the important genus Mycobacterium. This platform currently provides information of 2108 genome sequences of at least 55 Mycobacterium spp. A number of intuitive web-based tools have been integrated in MycoCAP particularly for comparative analysis including the PGC tool for comparison between two genomes, PathoProT for comparing the virulence genes among the Mycobacterium strains and the SuperClassification tool for the phylogenic classification of the Mycobacterium strains and a specialized classification system for strains of Mycobacterium abscessus. We hope the broad range of functions and easy-to-use tools provided in MycoCAP makes it an invaluable analysis platform to speed up the research discovery on mycobacteria for researchers. Database URL: http://mycobacterium.um.edu.my.

  1. Microaerobic growth and anaerobic survival of Mycobacterium avium, Mycobacterium intracellulare and Mycobacterium scrofulaceum

    Directory of Open Access Journals (Sweden)

    Amy Herndon Lewis

    2015-01-01

    Full Text Available Representative strains of Mycobacterium avium, Mycobacterium intracellulare and Mycobacterium scrofulaceum (MAIS grew at equal rates in laboratory medium at 21% (air and 12% oxygen. Growth in 6% oxygen proceeded at a 1.4–1.8-fold lower rate. Colony formation was the same at 21% (air and 6% oxygen. The MAIS strains survived rapid shifts from aerobic to anaerobic conditions as measured by two experimental approaches (Falkinham (1996 [1]. MAIS cells grown aerobically to log phase in broth were diluted, spread on agar medium, and incubated anaerobically for up to 20 days at 37 °C. Although no colonies formed anaerobically, upon transfer to aerobic conditions, greater than 25% of the colony forming units (CFU survived after 20 days of anaerobic incubation (Prince et al. (1989 [2]. MAIS cells grown in broth aerobically to log phase were sealed and vigorous agitation led to oxygen depletion (Wayne model. After 12 days anaerobic incubation, M. avium and M. scrofulaceum survival were high (>50%, while M. intracellulare survival was lower (22%. M. avium cells shifted to anaerobiosis in broth had increased levels of glycine dehydrogenase and isocitrate lyase. Growth of MAIS strains at low oxygen levels and their survival following a rapid shift to anaerobiosis is consistent with their presence in environments with fluctuating oxygen levels.

  2. Microaerobic growth and anaerobic survival of Mycobacterium avium, Mycobacterium intracellulare and Mycobacterium scrofulaceum.

    Science.gov (United States)

    Lewis, Amy Herndon; Falkinham, Joseph O

    2015-03-01

    Representative strains of Mycobacterium avium, Mycobacterium intracellulare and Mycobacterium scrofulaceum (MAIS) grew at equal rates in laboratory medium at 21% (air) and 12% oxygen. Growth in 6% oxygen proceeded at a 1.4-1.8-fold lower rate. Colony formation was the same at 21% (air) and 6% oxygen. The MAIS strains survived rapid shifts from aerobic to anaerobic conditions as measured by two experimental approaches (Falkinham (1996) [1]). MAIS cells grown aerobically to log phase in broth were diluted, spread on agar medium, and incubated anaerobically for up to 20 days at 37°C. Although no colonies formed anaerobically, upon transfer to aerobic conditions, greater than 25% of the colony forming units (CFU) survived after 20 days of anaerobic incubation (Prince et al. (1989) [2]). MAIS cells grown in broth aerobically to log phase were sealed and vigorous agitation led to oxygen depletion (Wayne model). After 12 days anaerobic incubation, M. avium and M. scrofulaceum survival were high (>50%), while M. intracellulare survival was lower (22%). M. avium cells shifted to anaerobiosis in broth had increased levels of glycine dehydrogenase and isocitrate lyase. Growth of MAIS strains at low oxygen levels and their survival following a rapid shift to anaerobiosis is consistent with their presence in environments with fluctuating oxygen levels. Copyright © 2015 Asian African Society for Mycobacteriology. Published by Elsevier Ltd. All rights reserved.

  3. Visible-light-induced photocatalysis of low-level methyl-tertiary butyl ether (MTBE) and trichloroethylene (TCE) using element-doped titanium dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Wan-Kuen; Yang, Chang-Hee [Department of Environmental Engineering, Kyungpook National University, Sankeokdong, Bukgu, Daegu 702-701 (Korea)

    2010-04-15

    While the photocatalytic degradation of various volatile organic compounds in conjunction with UV light has been widely reported, visible-light-induced photocatalytic degradation of low-levels of the pollutants MTBE and TCE, which have been linked to potential adverse health effects, is rarely reported. The present study examined whether visible-light-activated S- or N-doped TiO{sub 2} photocatalytic technology can be used to control indoor concentrations of MTBE and TCE. This study consists of the characterization of the doped TiO{sub 2} powders, as well as an investigation of their photocatalytic activities. In regards to both powders, a shift of the absorbance spectrum towards the visible light region was observed. An activity test suggested that these photocatalysts exhibited reasonably high degradation efficiencies towards MTBE and TCE under visible light irradiation. The degradation efficiencies of MTBE and TCE by S- and N-doped photocatalysts exceeded 75 and 80%, respectively, at input concentrations (IC) of 0.1 ppm. Degradation efficiency was dependent on both IC and relative humidity. TCE could enhance the degradation efficiency of MTBE even under visible-light irradiation. The estimated mineralization efficiencies (MEs) were comparable to those of previous studies conducted with UV/TiO{sub 2} systems. Similar to the relative degradation efficiencies, the ME of TCE was higher in comparison to that of MTBE. The CO production measured during the photocatalytic processes represented a negligible addition to indoor CO levels. These results suggest that visible-light-activated S- and N-doped TiO{sub 2} photocatalysts may prove a useful tool in the effort to improve indoor air quality. (author)

  4. Beta-lactamases of Mycobacterium tuberculosis and Mycobacterium kansasii.

    Science.gov (United States)

    Segura, C; Salvadó, M

    1997-09-01

    Re-emergence of infectious diseases caused by mycobacteria as well as the emergence of multiresistant strains of Mycobacterium has promoted the research on the use of beta-lactames in the treatment of such diseases. Mycobacteria produce beta-lactamases: M. tuberculosis produces a wide-spectrum beta-lactamase whose behaviour mimicks those of Gram-negative bacteria. M. kansasii produces also beta-lactamase which can be inhibited by clavulanic acid. An overview on beta-lactamases from both species is reported.

  5. Méditation et pratique de soi chez Malebranche.

    Directory of Open Access Journals (Sweden)

    Éric Dubreucq

    2004-04-01

    Full Text Available Une étude des Méditations pour se disposer à l’Humilité et à la pénitence qui les replace dans le cadre des pratiques de son époque, par exemple, chez François de Sales, celles de l’oraison, de la méditation et de la contemplation, permet d’apercevoir que l’une des thèses majeures du malebranchisme, la vision en Dieu, est un effet instauré dans le destinataire par un dispositif textuel. Celui-ci tire sa puissance prescriptive de l’a priori pratique où il s’inscrit. C’est à une opération de production de soi que l’exercice spirituel donne lieu : l’analyse des quatre premières Méditations chrétiennes et métaphysiques, en particulier, montre que c’est une organisation de la substance personnelle que provoque le travail spirituel sur soi. Celui-ci consiste à déterminer le rapport à soi comme relation d’une vision attentive à une activité illuminante, par un décentrement textuel du « je » vers le « tu ».One of the major Malebranche’s assertion, that we see truth in God, is not a mere theoretical thesis. I study first the Méditations pour se disposer à l’Humilité et à la pénitence and compare them with François de Sales’ spiritual exercitations, and show that prayer, meditation and contemplation constitute the practical frameworks of this period. The text of the Méditations is an apparatus which is fit to cause an effect in its target – the self of the reader : the vision in God. The practical a priori of the meditation provides the text with prescriptive power to transform the self. Then I study the Méditations chrétiennes et métaphysiques i-iv : we see that Malebranche set his textual apparatus so that it prescribes its receiver a form of « work-on-one’s-self ». The self is here produced by the organisation of relationship between attentive vision and lighting action, and this structure is built in the self by a movement, induced by the text, which leads the self from

  6. Prévalence et facteurs associés à la surcharge pondérale chez les ...

    African Journals Online (AJOL)

    30% des adolescentes et près de 10% des garçons sont soit en surpoids, soit obèses. (McQuaide, 2008). Des études ont estimé la prévalence de la surcharge pondérale chez les adolescents mexicains à 19,8% et chez les adolescents égyptiens à 12.1%. Les facteurs de risque étaient l'âge, le niveau d'instruction,.

  7. Methanol production by Mycobacterium smegmatis

    International Nuclear Information System (INIS)

    Weisman, L.S.; Ballou, C.E.

    1988-01-01

    Mycobacterium smegmatis cells produce [ 3 H]methanol when incubated with [methyl- 3 H]methionine. The methanol is derived from S-adenosylmethionine rather than methyltetrahydrofolate. M. smegmatis cells carboxymethylate several proteins, and some of the methanol probably results from their demethylation, but most of the methanol may come from an unidentified component with a high gel mobility. Although methanol in the medium reached 19 μM, it was not incorporated into the methylated mannose polysaccharide, a lipid carrier in this organism

  8. Mycobacterium arupense, Mycobacterium heraklionense, and a Newly Proposed Species, "Mycobacterium virginiense" sp. nov., but Not Mycobacterium nonchromogenicum, as Species of the Mycobacterium terrae Complex Causing Tenosynovitis and Osteomyelitis.

    Science.gov (United States)

    Vasireddy, Ravikiran; Vasireddy, Sruthi; Brown-Elliott, Barbara A; Wengenack, Nancy L; Eke, Uzoamaka A; Benwill, Jeana L; Turenne, Christine; Wallace, Richard J

    2016-05-01

    Mycobacterium terrae complex has been recognized as a cause of tenosynovitis, with M. terrae and Mycobacterium nonchromogenicum reported as the primary etiologic pathogens. The molecular taxonomy of the M. terrae complex causing tenosynovitis has not been established despite approximately 50 previously reported cases. We evaluated 26 isolates of the M. terrae complex associated with tenosynovitis or osteomyelitis recovered between 1984 and 2014 from 13 states, including 5 isolates reported in 1991 as M. nonchromogenicum by nonmolecular methods. The isolates belonged to three validated species, one new proposed species, and two novel related strains. The majority of isolates (20/26, or 77%) belonged to two recently described species: Mycobacterium arupense (10 isolates, or 38%) and Mycobacterium heraklionense (10 isolates, or 38%). Three isolates (12%) had 100% sequence identity to each other by 16S rRNA and 99.3 to 100% identity by rpoB gene region V sequencing and represent a previously undescribed species within the M. terrae complex. There were no isolates of M. terrae or M. nonchromogenicum, including among the five isolates reported in 1991. The 26 isolates were susceptible to clarithromycin (100%), rifabutin (100%), ethambutol (92%), and sulfamethoxazole or trimethoprim-sulfamethoxazole (70%). The current study suggests that M. arupense, M. heraklionense, and a newly proposed species ("M. virginiense" sp. nov.; proposed type strain MO-233 [DSM 100883, CIP 110918]) within the M. terrae complex are the major causes of tenosynovitis and osteomyelitis in the United States, with little change over 20 years. Species identification within this complex requires sequencing methods. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  9. ADVANCED OXIDATION PROCESS TECHNOLOGY (ULTRAVIOLET RADIATION/OZONE TREATMENT) FOR REMOVAL OF METHYL TERTIARY BUTYL ETHER (MTBE) IN GROUND WATER SUPPLIES.

    Science.gov (United States)

    U.S. EPA’s Office of Research and Development in Cincinnati, Ohio has been testing and evaluating MTBE removal in dechlorinated tap water using three oxidant combinations: hydrogen peroxide/ozone, ultraviolet irradiation (UV)/ozone, and UV/ozone/hydrogen peroxide. Pilot-scale st...

  10. Preparation of mesoporous alumina films by anodization: Effect of pretreatments on the aluminum surface and MTBE catalytic oxidation

    International Nuclear Information System (INIS)

    Vazquez, A.L.; Carrera, R.; Arce, E.; Castillo, N.; Castillo, S.; Moran-Pineda, M.

    2009-01-01

    Mesoporous materials are both scientifically and technologically important because of the presence of voids of controllable dimensions at atomic, molecular, and nanometric scales. Over the last decade, there has been both an increasing interest and research effort in the synthesis and characterization of these types of materials. The purposes of this work are to study the physical and chemical changes in the properties of mesoporous alumina films produced by anodization in sulphuric acid by different pretreatments on the aluminium surface such as mechanical polishing [MP] and electropolishing [EP]; and to compare their properties such as morphology, structure and catalytic activity with those present in commercial alumina. The morphologic and physical characterizations of the alumina film samples were carried out by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The chemical evaluations were performed by the oxidation of methyl-tert-butyl-ether (MTBE) at 400 deg. C under O 2 /He oxidizing conditions (Praxair, 2.0% O 2 /He balance). According to the results, the samples that presented higher activities than those in Al 2 O 3 /Al [MP] and commercial alumina in the MTBE oxidation (69%), were those prepared by Al 2 O 3 /Al [EP]. The average mesoporous diameter was 17 nm, and the morphological shape was equiaxial; thus, that pore distribution was the smallest of all with a homogeneous distribution.

  11. Preparation of mesoporous alumina films by anodization: Effect of pretreatments on the aluminum surface and MTBE catalytic oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Vazquez, A.L., E-mail: avazquezd@ipn.m [Departamento de Ingenieria Metalurgica, ESIQIE-IPN, AP 75-876, Mexico, D.F. (Mexico); Programa de Ingenieria Molecular, Instituto Mexicano del Petroleo, Eje Lazaro Cardenas 152, C.P. 07730, Mexico, D.F. (Mexico); Carrera, R. [Departamento de Ingenieria Metalurgica, ESIQIE-IPN, AP 75-876, Mexico, D.F. (Mexico); Programa de Ingenieria Molecular, Instituto Mexicano del Petroleo, Eje Lazaro Cardenas 152, C.P. 07730, Mexico, D.F. (Mexico); Arce, E. [Departamento de Ingenieria Metalurgica, ESIQIE-IPN, AP 75-876, Mexico, D.F. (Mexico); Castillo, N. [CINVESTAV, Departamento de Fisica. Av. IPN 2508, 07360, Mexico, D.F (Mexico); Castillo, S. [Departamento de Ingenieria Metalurgica, ESIQIE-IPN, AP 75-876, Mexico, D.F. (Mexico); Programa de Ingenieria Molecular, Instituto Mexicano del Petroleo, Eje Lazaro Cardenas 152, C.P. 07730, Mexico, D.F. (Mexico); Moran-Pineda, M. [Programa de Ingenieria Molecular, Instituto Mexicano del Petroleo, Eje Lazaro Cardenas 152, C.P. 07730, Mexico, D.F. (Mexico)

    2009-08-26

    Mesoporous materials are both scientifically and technologically important because of the presence of voids of controllable dimensions at atomic, molecular, and nanometric scales. Over the last decade, there has been both an increasing interest and research effort in the synthesis and characterization of these types of materials. The purposes of this work are to study the physical and chemical changes in the properties of mesoporous alumina films produced by anodization in sulphuric acid by different pretreatments on the aluminium surface such as mechanical polishing [MP] and electropolishing [EP]; and to compare their properties such as morphology, structure and catalytic activity with those present in commercial alumina. The morphologic and physical characterizations of the alumina film samples were carried out by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The chemical evaluations were performed by the oxidation of methyl-tert-butyl-ether (MTBE) at 400 deg. C under O{sub 2}/He oxidizing conditions (Praxair, 2.0% O{sub 2}/He balance). According to the results, the samples that presented higher activities than those in Al{sub 2}O{sub 3}/Al [MP] and commercial alumina in the MTBE oxidation (69%), were those prepared by Al{sub 2}O{sub 3}/Al [EP]. The average mesoporous diameter was 17 nm, and the morphological shape was equiaxial; thus, that pore distribution was the smallest of all with a homogeneous distribution.

  12. Whole genome sequence analysis of Mycobacterium suricattae

    KAUST Repository

    Dippenaar, Anzaan; Parsons, Sven David Charles; Sampson, Samantha Leigh; Van Der Merwe, Ruben Gerhard; Drewe, Julian Ashley; Abdallah, Abdallah; Siame, Kabengele Keith; Gey Van Pittius, Nicolaas Claudius; Van Helden, Paul David; Pain, Arnab; Warren, Robin Mark

    2015-01-01

    Tuberculosis occurs in various mammalian hosts and is caused by a range of different lineages of the Mycobacterium tuberculosis complex (MTBC). A recently described member, Mycobacterium suricattae, causes tuberculosis in meerkats (Suricata suricatta) in Southern Africa and preliminary genetic analysis showed this organism to be closely related to an MTBC pathogen of rock hyraxes (Procavia capensis), the dassie bacillus. Here we make use of whole genome sequencing to describe the evolution of the genome of M. suricattae, including known and novel regions of difference, SNPs and IS6110 insertion sites. We used genome-wide phylogenetic analysis to show that M. suricattae clusters with the chimpanzee bacillus, previously isolated from a chimpanzee (Pan troglodytes) in West Africa. We propose an evolutionary scenario for the Mycobacterium africanum lineage 6 complex, showing the evolutionary relationship of M. africanum and chimpanzee bacillus, and the closely related members M. suricattae, dassie bacillus and Mycobacterium mungi.

  13. Whole genome sequence analysis of Mycobacterium suricattae

    KAUST Repository

    Dippenaar, Anzaan

    2015-10-21

    Tuberculosis occurs in various mammalian hosts and is caused by a range of different lineages of the Mycobacterium tuberculosis complex (MTBC). A recently described member, Mycobacterium suricattae, causes tuberculosis in meerkats (Suricata suricatta) in Southern Africa and preliminary genetic analysis showed this organism to be closely related to an MTBC pathogen of rock hyraxes (Procavia capensis), the dassie bacillus. Here we make use of whole genome sequencing to describe the evolution of the genome of M. suricattae, including known and novel regions of difference, SNPs and IS6110 insertion sites. We used genome-wide phylogenetic analysis to show that M. suricattae clusters with the chimpanzee bacillus, previously isolated from a chimpanzee (Pan troglodytes) in West Africa. We propose an evolutionary scenario for the Mycobacterium africanum lineage 6 complex, showing the evolutionary relationship of M. africanum and chimpanzee bacillus, and the closely related members M. suricattae, dassie bacillus and Mycobacterium mungi.

  14. Piqures massives par un essaim d�abeilles chez un enfant

    Directory of Open Access Journals (Sweden)

    Mohamed Adnane Berdai

    2011-10-01

    Full Text Available Les piqures multiples d�abeilles sont responsables d�envenimation severe. Nous rapportons un cas d�une attaque massive par un essaim d�abeilles chez un enfant de sept ans. Sa gravite est liee a la localisation cephalique et au nombre important des piqures qui etait d�environ 270. Ses complications etaient l�insuffisance renale, l�anemie et une conjonctivite. La prise en charge etait symptomatique avec bonne evolution clinique et biologique.

  15. Infection par le VIH chez les patientes atteintes de cancer du sein en ...

    African Journals Online (AJOL)

    L'objectif était de déterminer la prévalence de l'infection à VIH chez les patientes atteintes de cancer du sein et de comparer les caractéristiques anatomocliques et thérapeutiques de ces cancers du sein par rapports aux patientes non infectées par le VIH. Il s'agissait d'une étude rétrospective et analytique comparant les ...

  16. Prevalence de l'infection a VIH chez les patients victimes d'un ...

    African Journals Online (AJOL)

    Introduction: Le VIH/SIDA et son traitement antirétroviral sont associés à un risque élevé de maladies cardiovasculaires comme les accidents vasculaires cérébraux (AVC). L'objectif de cette étude était d'estimer la prévalence du VIH et d'identifier ses facteurs associés chez les patients hospitalisés pour un AVC. Méthode: ...

  17. Épidémiologie de l'intoxication par envenimation chez les enfants ...

    African Journals Online (AJOL)

    Introduction: L'intoxication par envenimation est l'ensemble des manifestations locales et générales induites par la pénétration dans l'organisme d'une substance toxique produite par un animal venimeux. Le but de notre travail était d'étudier les signes cliniques des intoxications par envenimation chez les enfants de 0 à 15 ...

  18. Evaluation des complications cardiaques chez les hémodialysés ...

    African Journals Online (AJOL)

    Introduction: L'évaluation cardiovasculaire est essentielle en hémodialyse périodique car les affections cardiovasculaires sont la première cause de mortalité chez les hémodialysés chroniques. Nous avons conduit cette étude afin de déterminer la prévalence et le type des différentes complications cardiovasculaires et ...

  19. La surveillance des abords vasculaires chez les hémodialysés ...

    African Journals Online (AJOL)

    La fistule artério veineuse a présenté très peu de complications chez les patients. Mots clés : Abord vasculaire, Hémodialyse, insuffisance rénale chronique. English abstract. Monitoring of vascular access in chronic hemodialysis patients at the National Hospital of Niamey Lamordé The purpose of this cross-sectional study ...

  20. Evaluation de la prise en charge du paludisme chez les enfants de ...

    African Journals Online (AJOL)

    Devant l'ampleur du paludisme en pays intertropicaux le rôle du personnel soignant dans la réduction de la fréquence des cas de paludisme grave et de son taux de létalité devient évident. Nous avons alors voulu évaluer la qualité de la prise en charge de cette affection chez l'enfant de moins de cinq ans dans un hôpital ...

  1. MANIfESTATIONS ORL dU RGO ChEz L'ENfANT

    African Journals Online (AJOL)

    7 déc. 2011 ... Le volume de salive déglutie et sa concentration en bicarbonates semblent jouer un rôle primordial dans la clairance œsophagienne (4, 6). vidange gastrique : Des études récentes ont montré qu'il existait une gastro- parésie et des troubles de la motricité gastro-intestinale chez des enfants atteints de RGO ...

  2. Original Paper Evaluation de la fonction rénale chez les patients ...

    African Journals Online (AJOL)

    Evaluation de la fonction rénale chez les patients atteints de maladie cardio vasculaire (MCV) : comparaison entre ... Mots clés : Cystatine C, créatinine, insuffisance rénale, débit de filtration glomérulaire, maladies cardiovasculaires. Evaluation of the ... L'insuffisance rénale chronique (IRC) et les maladies cardiovasculaires ...

  3. Lymphome B à grandes cellules primitif du médiastin chez la femme ...

    African Journals Online (AJOL)

    Les patientes ont été adressées à l'institut national d'oncologie pour prise en charge thérapeutique. Le pronostic du LBPM est réservé, il survient volontiers chez des femmes jeunes, ce qui rend d'autant plus nécessaire une thérapeutique agressive afin d'améliorer le taux de survie. The Pan African Medical Journal 2016; ...

  4. Les besoins en isoleucine, valine et leucine chez le porcelet entre 7 et 15 kg

    DEFF Research Database (Denmark)

    Assadi Soumeh, Elham; van Milgen, Jaap; Sloth, Niels Morten

    2015-01-01

    croissance s’ils sont fournis en deçà du besoin. Des études de métaanalyse révèlent que peu de données de type dose‐réponse sont disponibles chez le porcelet pour l’Ile, notamment avec des aliments exempts de cellules de sang, et la Val (van Milgen et al., 2012, 2013). Par ailleurs, une revue de la...

  5. Mycobacterium intracellulare Infection Mimicking Progression of Scleroderma

    DEFF Research Database (Denmark)

    Krabbe, Simon; Engelhart, Merete; Thybo, Sören

    2017-01-01

    This case report describes a patient with scleroderma who developed Mycobacterium intracellulare infection, which for more than a year mimicked worsening of her connective tissue disorder. The patient was diagnosed with scleroderma based on puffy fingers that developed into sclerodactyly, abnormal......, unfortunately with significant scarring. Immunodeficiency testing was unremarkable. In summary, an infection with Mycobacterium intracellulare was mistaken for an unusually severe progression of scleroderma....

  6. Les effets neurocognitifs de la vitamine D chez la personne âgée

    Directory of Open Access Journals (Sweden)

    Annweiler Cédric

    2014-05-01

    Full Text Available Une alimentation saine, en particulier la consommation régulière d’aliments riches en vitamine D, est un facteur protecteur contre la survenue de pathologie démentielle chez la personne âgée. Outre ses propriétés traditionnellement reconnues de régulation du métabolisme phosphocalcique, la vitamine D est une hormone neurostéroïde indispensable au fonctionnement neurophysiologique (régulation de neurotransmetteurs et de neurotrophines avec, en plus, une action neuroprotectrice anti-inflammatoire et anti-oxydante. Au contraire son insuffisance, extrêmement prévalente chez la personne âgée, pourrait engendrer des dysfonctionnements du système nerveux central, expliquant en partie les troubles cognitifs rencontrés dans cette population. L’épidémiologie est cohérente avec cette notion et rapporte une association entre hypovitaminose D et trouble cognitif, que ce soit en population âgée générale ou chez le malade Alzheimer. Les essais d’intervention confirment la relation de causalité et quantifient l’efficacité cognitive de la supplémentation vitaminique D chez la personne âgée, ce qui suscite des perspectives en matière de prévention primo-secondaire des troubles cognitifs chez la personne âgée par un apport exogène de vitamine D. En particulier, tandis que les traitements anti-démence symptomatiques actuellement disponibles ne font que ralentir transitoirement le déclin cognitif, les futures possibilités de traitement pourraient reposer sur des combinaisons médicamenteuses luttant contre plusieurs mécanismes neurodégénératifs à la fois. À ce titre, la vitamine D améliore l’efficacité de la mémantine en termes de protection neuronale et de prévention du déclin cognitif au cours de la maladie d’Alzheimer.

  7. Whole-genome sequence analysis of the Mycobacterium avium complex and proposal of the transfer of Mycobacterium yongonense to Mycobacterium intracellulare subsp. yongonense subsp. nov.

    Science.gov (United States)

    Castejon, Maria; Menéndez, Maria Carmen; Comas, Iñaki; Vicente, Ana; Garcia, Maria J

    2018-06-01

    Bacterial whole-genome sequences contain informative features of their evolutionary pathways. Comparison of whole-genome sequences have become the method of choice for classification of prokaryotes, thus allowing the identification of bacteria from an evolutionary perspective, and providing data to resolve some current controversies. Currently, controversy exists about the assignment of members of the Mycobacterium avium complex, as is for the cases of Mycobacterium yongonense and 'Mycobacterium indicus pranii'. These two mycobacteria, closely related to Mycobacterium intracellulare on the basis of standard phenotypic and single gene-sequences comparisons, were not considered a member of such species on the basis on some particular differences displayed by a single strain. Whole-genome sequence comparison procedures, namely the average nucleotide identity and the genome distance, showed that those two mycobacteria should be considered members of the species M. intracellulare. The results were confirmed with other whole-genome comparison supplementary methods. According to the data provided, Mycobacterium yongonense and 'Mycobacterium indicus pranii' should be considered and renamed and included as members of M. intracellulare. This study highlights the problems caused when a novel species is accepted on the basis of a single strain, as was the case for M. yongonense. Based mainly on whole-genome sequence analysis, we conclude that M. yongonense should be reclassified as a subspecies of Mycobacterium intracellulareas Mycobacterium intracellularesubsp. yongonense and 'Mycobacterium indicus pranii' classified in the same subspecies as the type strain of Mycobacterium intracellulare and classified as Mycobacterium intracellularesubsp. intracellulare.

  8. Complete Genome Sequence of Mycobacterium phlei Type Strain RIVM601174

    KAUST Repository

    Abdallah, A. M.; Rashid, M.; Adroub, S. A.; Arnoux, M.; Ali, Shahjahan; van Soolingen, D.; Bitter, W.; Pain, Arnab

    2012-01-01

    Mycobacterium phlei is a rapidly growing nontuberculous Mycobacterium species that is typically nonpathogenic, with few reported cases of human disease. Here we report the whole genome sequence of M. phlei type strain RIVM601174.

  9. Complete Genome Sequence of Mycobacterium phlei Type Strain RIVM601174

    KAUST Repository

    Abdallah, A. M.

    2012-05-24

    Mycobacterium phlei is a rapidly growing nontuberculous Mycobacterium species that is typically nonpathogenic, with few reported cases of human disease. Here we report the whole genome sequence of M. phlei type strain RIVM601174.

  10. Mycobacterium chelonae infections associated with bee venom acupuncture.

    Science.gov (United States)

    Cho, Sun Young; Peck, Kyong Ran; Kim, Jungok; Ha, Young Eun; Kang, Cheol-In; Chung, Doo Ryeon; Lee, Nam Yong; Song, Jae-Hoon

    2014-03-01

    We report 3 cases of Mycobacterium chelonae infections after bee venom acupuncture. All were treated with antibiotics and surgery. Mycobacterium chelonae infections should be included in the differential diagnosis of chronic skin and soft tissue infections following bee venom acupuncture.

  11. The draft genome of Mycobacterium aurum , a potential model organism for investigating drugs against Mycobacterium tuberculosis and Mycobacterium leprae

    Directory of Open Access Journals (Sweden)

    Jody Phelan

    2015-01-01

    Full Text Available Mycobacterium aurum (M. aurum is an environmental mycobacteria that has previously been used in studies of anti-mycobacterial drugs due to its fast growth rate and low pathogenicity. The M. aurum genome has been sequenced and assembled into 46 contigs, with a total length of 6.02 Mb containing 5684 annotated protein-coding genes. A phylogenetic analysis using whole genome alignments positioned M. aurum close to Mycobacterium vaccae and Mycobacterium vanbaalenii, within a clade related to fast-growing mycobacteria. Large-scale genomic rearrangements were identified by comparing the M. aurum genome to those of Mycobacterium tuberculosis and Mycobacterium leprae. M. aurum orthologous genes implicated in resistance to anti-tuberculosis drugs in M. tuberculosis were observed. The sequence identity at the DNA level varied from 68.6% for pncA (pyrazinamide drug-related to 96.2% for rrs (streptomycin, capreomycin. We observed two homologous genes encoding the catalase-peroxidase enzyme (katG that is associated with resistance to isoniazid. Similarly, two emb B homologues were identified in the M. aurum genome. In addition to describing for the first time the genome of M. aurum , this work provides a resource to aid the use of M. aurum in studies to develop improved drugs for the pathogenic mycobacteria M. tuberculosis and M. leprae.

  12. The draft genome of Mycobacterium aurum, a potential model organism for investigating drugs against Mycobacterium tuberculosis and Mycobacterium leprae

    KAUST Repository

    Phelan, Jody

    2015-06-04

    Mycobacterium aurum (M. aurum) is an environmental mycobacteria that has previously been used in studies of anti-mycobacterial drugs due to its fast growth rate and low pathogenicity. The M. aurum genome has been sequenced and assembled into 46 contigs, with a total length of 6.02 Mb containing 5684 annotated protein-coding genes. A phylogenetic analysis using whole genome alignments positioned M. aurum close to Mycobacterium vaccae and Mycobacterium vanbaalenii, within a clade related to fast-growing mycobacteria. Large-scale genomic rearrangements were identified by comparing the M. aurum genome to those of Mycobacterium tuberculosis and Mycobacterium leprae. M. aurum orthologous genes implicated in resistance to anti-tuberculosis drugs in M. tuberculosis were observed. The sequence identity at the DNA level varied from 68.6% for pncA (pyrazinamide drug-related) to 96.2% for rrs (streptomycin, capreomycin). We observed two homologous genes encoding the catalase-peroxidase enzyme (katG) that is associated with resistance to isoniazid. Similarly, two embB homologues were identified in the M. aurum genome. In addition to describing for the first time the genome of M. aurum, this work provides a resource to aid the use of M. aurum in studies to develop improved drugs for the pathogenic mycobacteria M. tuberculosis and M. leprae.

  13. The draft genome of Mycobacterium aurum, a potential model organism for investigating drugs against Mycobacterium tuberculosis and Mycobacterium leprae

    KAUST Repository

    Phelan, Jody; Maitra, Arundhati; McNerney, Ruth; Nair, Mridul; Gupta, Antima; Coll, Francesc; Pain, Arnab; Bhakta, Sanjib; Clark, Taane G.

    2015-01-01

    Mycobacterium aurum (M. aurum) is an environmental mycobacteria that has previously been used in studies of anti-mycobacterial drugs due to its fast growth rate and low pathogenicity. The M. aurum genome has been sequenced and assembled into 46 contigs, with a total length of 6.02 Mb containing 5684 annotated protein-coding genes. A phylogenetic analysis using whole genome alignments positioned M. aurum close to Mycobacterium vaccae and Mycobacterium vanbaalenii, within a clade related to fast-growing mycobacteria. Large-scale genomic rearrangements were identified by comparing the M. aurum genome to those of Mycobacterium tuberculosis and Mycobacterium leprae. M. aurum orthologous genes implicated in resistance to anti-tuberculosis drugs in M. tuberculosis were observed. The sequence identity at the DNA level varied from 68.6% for pncA (pyrazinamide drug-related) to 96.2% for rrs (streptomycin, capreomycin). We observed two homologous genes encoding the catalase-peroxidase enzyme (katG) that is associated with resistance to isoniazid. Similarly, two embB homologues were identified in the M. aurum genome. In addition to describing for the first time the genome of M. aurum, this work provides a resource to aid the use of M. aurum in studies to develop improved drugs for the pathogenic mycobacteria M. tuberculosis and M. leprae.

  14. The draft genome of Mycobacterium aurum, a potential model organism for investigating drugs against Mycobacterium tuberculosis and Mycobacterium leprae.

    Science.gov (United States)

    Phelan, Jody; Maitra, Arundhati; McNerney, Ruth; Nair, Mridul; Gupta, Antima; Coll, Francesc; Pain, Arnab; Bhakta, Sanjib; Clark, Taane G

    2015-09-01

    Mycobacterium aurum (M. aurum) is an environmental mycobacteria that has previously been used in studies of anti-mycobacterial drugs due to its fast growth rate and low pathogenicity. The M. aurum genome has been sequenced and assembled into 46 contigs, with a total length of 6.02Mb containing 5684 annotated protein-coding genes. A phylogenetic analysis using whole genome alignments positioned M. aurum close to Mycobacterium vaccae and Mycobacterium vanbaalenii, within a clade related to fast-growing mycobacteria. Large-scale genomic rearrangements were identified by comparing the M. aurum genome to those of Mycobacterium tuberculosis and Mycobacterium leprae. M. aurum orthologous genes implicated in resistance to anti-tuberculosis drugs in M. tuberculosis were observed. The sequence identity at the DNA level varied from 68.6% for pncA (pyrazinamide drug-related) to 96.2% for rrs (streptomycin, capreomycin). We observed two homologous genes encoding the catalase-peroxidase enzyme (katG) that is associated with resistance to isoniazid. Similarly, two embB homologues were identified in the M. aurum genome. In addition to describing for the first time the genome of M. aurum, this work provides a resource to aid the use of M. aurum in studies to develop improved drugs for the pathogenic mycobacteria M. tuberculosis and M. leprae. Copyright © 2015 Asian-African Society for Mycobacteriology. Published by Elsevier Ltd. All rights reserved.

  15. The MTBE-plant at Kaarstoe, Norway. Consequences for industry and commerce, labour market and local government finance

    International Nuclear Information System (INIS)

    Stokka, A.; Nilssen, I.

    1995-05-01

    The paper discusses some of the results of a consequence analysis of the establishment of a MTBE-plant at Kaarstoe, Norway. The supplies from local subcontractors to the construction and operation of the plant are likely to be of the same extent as for previous constructions, but the supplies from the Norwegian industry will probably be less because of limited experience with petrochemistry. A high investment level offshore may lead to a shortage of some categories of Norwegian and local personnel during the construction. The number of people directly employed at the construction site plus the number of those throughout the Haugesund area who work for the plant may amount to 800-900 in 1994. During operation, the plant will employ 140-150 local people. For the local governments the plant implies considerable tax revenues: property tax, personal tax and corporation tax. 10 refs., 7 figs., 16 tabs

  16. Enfermedad por Mycobacterium simiae y "Mycobacterium sherrisii" en la Argentina

    Directory of Open Access Journals (Sweden)

    Lucía Barrera

    2010-08-01

    Full Text Available Se presenta información reunida retrospectivamente sobre casos de micobacteriosis originados por Mycobacterium simiae (n = 4 y "M. sherrisii" (n = 6. Los casos ocurrieron entre pacientes con sida (n = 6, historia de silicosis (n = 2 o tuberculosis previa (n = 1. Un caso se perdió luego de diagnosticado y nueve fueron tratados con esquemas terapéuticos basados en claritromicina, etambutol y quinolonas. La respuesta fue muy pobre: cinco pacientes fallecieron (cuatro eran HIV positivos, tres permanecieron crónicos y sólo uno curó. Estas micobacterias originaron 2.1% de los casos de micobacteriosis registrados en un período de ocho años. La distinción de estas micobacterias raras de otras más frecuentes por métodos moleculares rápidos, parece ser clínicamente útil para advertir sobre la dificultad que puede presentar el tratamiento. Sin embargo, la diferenciación genotípica entre M. simiae y "M. sherrisii" parecería no ser clínicamente relevante, dado que no quedaron expuestas características que distingan a los pacientes afectados por los dos microorganismos tan estrechamente relacionados.

  17. Mycobacterium mageritense Parotitis in an Immunocompetent Adult.

    Science.gov (United States)

    Okabe, Taro; Sasahara, Teppei; Suzuki, Jun; Onishi, Tsubasa; Komura, Masayoshi; Hagiwara, Shigehiro; Suzuki, Hiromichi; Morisawa, Yuji

    2018-03-01

    Mycobacterium mageritense , a rapidly growing mycobacterium, is a rare clinical pathogen. Furthermore, parotitis due to non-tuberculosis mycobacterium is very rare in adults. Herein, we report the first case of M. mageritense parotitis in an immunocompetent adult. A 40-year-old man presented with swelling in a left parotid lesion. He was diagnosed with parotitis. The culture from the parotid abscess grew M. mageritense . He was unsuccessfully treated with levofloxacin monotherapy. Trimethoprim-sulfamethoxazole was added, leading to some clinical response; however, the erythema persisted despite 14 months of antibiotic therapy. Subsequently, the skin lesion was surgically removed. The antibiotic treatment was ceased a week after surgery as the postoperative course was uneventful and the lesion had improved. No recurrence was noted at 7 months after surgery. Although extremely rare, M. mageritense can cause parotitis in immunocompetent adults, and may not be sufficiently treated with antibiotics alone.

  18. Draft Genome Sequence of Mycobacterium chimaera Type ...

    Science.gov (United States)

    We report the draft genome sequence of the type strain Mycobacterium chimaera Fl-0169T, a member of the Mycobacterium avium complex (MAC). M. chimaera Fl-0169T was isolated from a patient in Italy and is highly similar to strains of M. chimaera isolated in Ireland, though Fl-0169T possesses unique virulence genes. Evidence suggests that M. avium, M. intracellulare, and M. chimaera are differently virulent and a comparative genomic analysis is critically needed to identify diagnostic targets that reliably differentiate species of MAC. With treatment costs for Mycobacterium infections estimated to be >$1.8 B annually in the U.S., correct species identification will result in improved treatment selection, lower costs, and improved patient outcomes.

  19. Some aspects of sulphite metabolism in plants; Quelques aspects du metabolisme du sulfite chez les vegetaux

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Milan, Hernan

    1958-05-15

    As sulphite appears to be an intermediate substance in the degradation of sulphur-containing amino acids, and has an important metabolic role, notably for plants, this research thesis aims at comparing transformations which may occur for a same chemical compound (the sulphite) in various organisms belonging to different species or kingdoms. More particularly, the author studied the formation of sulphite in vegetal tissues, and the oxidisation of sulphite into sulfate within these tissues. In vitro experiments have been performed with oat, while in vivo experiments have been performed on tobacco plants [French] Le sulfite apparait comme une substance intermediaire de la degradation des acides amines soufres. Son role dans la biosynthese de certains d'entre eux, problematique chez les mammiferes, est certain chez les oiseaux, qui, a cet egard, se comportent comme des autotrophes partiels, puisqu'ils reduisent le sulfate en sulfite. On s'apercoit ainsi qu'un degre d'evolution moindre confere au sulfite une importance metabolique plus grande. On peut s'attendre a trouver chez les vegetaux un role encore accru pour le sulfite. Le present travail entre dans ce cadre d'etudes comparees des transformations que peut subir un meme type de compose chimique: le sulfite, dans divers organismes appartenant a des especes ou a des regnes differents. Les donnees acquises exposees ici auront trait aux deux points suivants: I - La formation du sulfite dans les tissus vegetaux, II - L'oxydation dans ces tissus, du sulfite en sulfate. L'avoine nous a servi comme materiel de depart pour les experiences faites in vitro. Cette plante presente en effet l'avantage de se bien cultiver en toutes saisons, de se broyer facilement, et d'etre depourvue au maximum de mucilages, de resines, substances genantes pour l'analyse ulterieure. Les essais faits in vivo, ont mis en oeuvre des plants de tabac, qui permettent une nutrition par le petiole ou par la tige particulierement aisee.

  20. Mortalite liee au VIH chez les enfants aux Chu campus et tokoin de ...

    African Journals Online (AJOL)

    Introduction. Le but de ce travail était d'étudier la mortalité liée au VIH chez les enfants séropositifs aux CHU-Campus et Tokoin de Lomé. Patients et méthode. Il s'est agi d'une étude prospective qui s'est déroulée dans les services de pédiatrie des CHU-Campus et Tokoin de Lomé et qui a couvert une période de 6 mois ...

  1. Grippe aviaire chez les oiseaux migrateurs : réseau régional de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La souche du virus de l'influenza aviaire hautement pathogène (H5N1) est responsable d'une forme grave de la maladie liée à une mortalité élevée chez la volaille d'élevage, les oiseaux d'eau et d'autres espèces d'oiseaux. Même si le mode de propagation de la maladie à l'échelle internationale est encore mal compris, ...

  2. Les dysthyroïdies chez l'hémodialysé chronique | Zbiti | Pan African ...

    African Journals Online (AJOL)

    Introduction: Les dysthyroïdies chez l'hémodialysé chronique sont représentées par une hypothyroïdie: dite le syndrome de basse T3, actuellement nommée "le syndrome de la maladie euthyroïdienne". L'objectif de notre travail est de déterminer le profil thyroïdien de nos HDC afin de préciser la prévalence des différents ...

  3. La systématique de l’esprit pratique chez Wolff, Kant, Fichte et Hegel

    OpenAIRE

    Siep, Ludwig

    2011-01-01

    En dépit des grands bouleversements systématiques dans la philosophie allemande du xviiie siècle, la continuité est étonnante, de Wolff à Hegel, pour ce qui concerne le contenu des doctrines sur la raison pratique. Une comparaison de ces doctrines chez Wolff, Kant, Fichte et Hegel peut révéler l’intention et les raisons pour lesquelles chacun de ces auteurs modifia la systématique des différentes facultés. À partir de Kant, autonomie et liberté deviennent les concepts directeurs permettant de...

  4. Étude des facteurs de risque du burnout chez les casques bleus ...

    African Journals Online (AJOL)

    Introduction: Il est devenu un problème de santé mentale au sein des casques bleus. L'objectif de cette étude était d'explorer les facteurs de risque du burnout chez les casques sénégalais en mission de maintien de la paix au Darfour. Méthode: Cette étude est transversale et analytique. Elle s'est déroulée du 19 avril au 20 ...

  5. Polymorphisme de l'APO A-IV chez les togolais: fréquences et ...

    African Journals Online (AJOL)

    Le polymorphisme génétique de l'apolipoprotéine A-IV (apo A-IV) a été étudié chez 601 togolais dont 252 sujets d'un isolat relatif, les Adélé et 349 sujets des ethnies, Ewé, Mina, Ouatchi originaires de la côte atlantique. La détermination des phénotypes a été réalisée par isoélectrofocalisation (IEF) sur gel de ...

  6. Répercussions socioéconomiques de la grippe aviaire chez les ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La souche du virus de l'influenza aviaire hautement pathogène (H5N1) est responsable d'une forme grave de la maladie liée à une mortalité élevée chez la volaille d'élevage, les oiseaux d'eau et d'autres espèces d'oiseaux. Les autorités de la santé publique craignent une mutation de cette souche hautement virulente qui ...

  7. Mycobacterium chelonae y Mycobacterium abscessus: patógenos emergentes

    Directory of Open Access Journals (Sweden)

    Mónica M. Ortegón

    1996-09-01

    Full Text Available Mycobacterium chelonae es el nombre correcto para la micobacteria aislada en 1903 de los pulmones enfermos de una tortuga marina. En una especie distinta de Mycobacterium fo/tuitum, aislado de ranas en 1905, y de Mycobacterium abscessus, considerado actualmente como una subespecie de M chelonae. Estas tres especies son las únicas patógenas para el hombre dentro del grupo de micobacterias ambientales o atipicas, de crecimiento rápido, las cuales se caracterizan por formar colonias en cultivo en menos de siete días. Son agentes etiológicos de nódulos y abscesos cutáneos, localizados y diseminados, de lesiones postoperatorias, usualmente en la cicatriz quirúrgica, de lesiones pulmonares y de linfadenitis granulomatosa, de osteomielitis y de queratitis, entre otras. Las lesiones cutáneas y de los tejidos blandos son las más frecuentes y resultan generalmente de la inoculación traumática de esta micobacteria. Histopatológicamente, los nódulos y abscesos muestran un proceso inflamatorio, supurativo y granulomatoso, mixto, en el que en la cuarta parte de los casos pueden demostrarse conglomerados de bacilos ácido alcohol resistentes, que tienden a estar situados en una vacuola en el centro del absceso. En Colombia, se han descrito tres brotes de abscesos subcutáneos producidos por bacterias ambientales, secundarios a la aplicación de inyecciones contaminadas con el germen causal: en 1981, en Bucaramanga, luego de la aplicación de la vacuna contra la fiebre amarilla, en 50 personas, la mayoría niños; en 1989, en Medellin, por la inyección subcutánea de alergenos, en 13 personas; y, en 1993, en varias ciudades de la costa atlántica, luego de aplicaciones subcutáneas de xilocaína, como tratamiento bionergético, en 297 pacientes. Existen otros informes aislados de casos posttraumáticos.La enfermedad diseminada por micobacterias de rápido crecimiento, se presenta en pacientes inmunosuprimidos. En la biopsia, predominan los

  8. Mycobacterium franklinii sp. nov., a species closely related to members of the Mycobacterium chelonae-Mycobacterium abscessus group.

    Science.gov (United States)

    Lourenço Nogueira, Christiane; Simmon, Keith E; Chimara, Erica; Cnockaert, Margo; Carlos Palomino, Juan; Martin, Anandi; Vandamme, Peter; Brown-Elliott, Barbara A; Wallace, Richard; Cardoso Leão, Sylvia

    2015-07-01

    Two isolates from water, D16Q19 and D16R27, were shown to be highly similar in their 16S rRNA, 16S-23S internal transcribed spacer (ITS), hsp65 and rpoB gene sequences to 'Mycobacterium franklinii' DSM 45524, described in 2011 but with the name not validly published. They are all nonpigmented rapid growers and are related phenotypically and genetically to the Mycobacterium chelonae-Mycobacterium abscessus group. Extensive characterization by phenotypic analysis, biochemical tests, drug susceptibility testing, PCR restriction enzyme analysis of the hsp65 gene and ITS, DNA sequencing of housekeeping genes and DNA-DNA hybridization demonstrated that 'M. franklinii' DSM 45524, D16Q19 and D16R27 belong to a single species that is separated from other members of the M. chelonae-M. abscessus group. On the basis of these results we propose the formal recognition of Mycobacterium franklinii sp. nov. Strain DSM 45524(T) ( = ATCC BAA-2149(T)) is the type strain.

  9. Photodynamic inactivation of the models Mycobacterium phlei and Mycobacterium smegmatis in vitro

    Science.gov (United States)

    Bruce-Micah, R.; Gamm, U.; Hüttenberger, D.; Cullum, J.; Foth, H.-J.

    2009-07-01

    Photodynamic inactivation (PDI) of bacterial strains presents an attractive potential alternative to antibiotic therapies. Success is dependent on the effective accumulation in bacterial cells of photochemical substances called photosensitizers, which are usually porphyrins or their derivatives. The kinetics of porphyrin synthesis after treatment with the precursor ALA and the accumulation of the Chlorin e6 and the following illumination were studied. The goal was to estimate effectivity of the destructive power of these PS in vitro in respect of the physiological states of Mycobacteria. So the present results examine the cell destruction by PDI using ALA-induced Porphyrins and Chlorin e6 accumulated in Mycobacterium phlei and Mycobacterium smegmatis, which serve as models for the important pathogens Mycobacterium tuberculosis, Mycobacterium leprae and Mycobacterium bovis. We could show that both Mycobacterium after ALA and Chlorin e6 application were killed by illumination with light of about 662 nm. A reduction of about 97% could be reached by using a lightdose of 70 mW/cm2.

  10. Targeting phenotypically tolerant Mycobacterium tuberculosis

    Science.gov (United States)

    Gold, Ben; Nathan, Carl

    2016-01-01

    While the immune system is credited with averting tuberculosis in billions of individuals exposed to Mycobacterium tuberculosis, the immune system is also culpable for tempering the ability of antibiotics to deliver swift and durable cure of disease. In individuals afflicted with tuberculosis, host immunity produces diverse microenvironmental niches that support suboptimal growth, or complete growth arrest, of M. tuberculosis. The physiological state of nonreplication in bacteria is associated with phenotypic drug tolerance. Many of these host microenvironments, when modeled in vitro by carbon starvation, complete nutrient starvation, stationary phase, acidic pH, reactive nitrogen intermediates, hypoxia, biofilms, and withholding streptomycin from the streptomycin-addicted strain SS18b, render M. tuberculosis profoundly tolerant to many of the antibiotics that are given to tuberculosis patients in a clinical setting. Targeting nonreplicating persisters is anticipated to reduce the duration of antibiotic treatment and rate of post-treatment relapse. Some promising drugs to treat tuberculosis, such as rifampicin and bedaquiline, only kill nonreplicating M. tuberculosis in vitro at concentrations far greater than their minimal inhibitory concentrations against replicating bacilli. There is an urgent demand to identify which of the currently used antibiotics, and which of the molecules in academic and corporate screening collections, have potent bactericidal action on nonreplicating M. tuberculosis. With this goal, we review methods of high throughput screening to target nonreplicating M. tuberculosis and methods to progress candidate molecules. A classification based on structures and putative targets of molecules that have been reported to kill nonreplicating M. tuberculosis revealed a rich diversity in pharmacophores. However, few of these compounds were tested under conditions that would exclude the impact of adsorbed compound acting during the recovery phase of

  11. Luxation postérieure de l'épaule chez un sujet sportif traitée par ...

    African Journals Online (AJOL)

    Luxation postérieure de l'épaule chez un sujet sportif traitée par transfert pédiculé du sub-scapulaire. Adil El Alaoui, Ilyas Rabhi, Aliou Bah, Mouhcine Sbiyaa, Amine Mezzani, Badr Alami, Amine Marzouki, Fawzi Boutayeb ...

  12. Préoccupations de carrière chez les médecins de travail des ...

    African Journals Online (AJOL)

    Préoccupations de carrière chez les médecins de travail des groupements de Médecine de travail en Tunisie. Irtyah Merchaoui, Asma Chouchène, Ines Bouanène, Néila Chaari, Wassim Zrafi, Adnène Henchi, Mohamed Akrout, Charfeddine Amri ...

  13. Detection of Mycobacterium Tuberculosis by using PCR

    International Nuclear Information System (INIS)

    Suhadi, F; Dadang-Sudrajat; Maria-Lina, R.

    1996-01-01

    Polymerase Chain Reaction (PCR) procedure using three primary set derived from repetitive DNA sequence specific to mycobacteria was used to diagnose pathogenic Mycobacterium tuberculosis. The assay was specific for M. tuberculosis and could be used to detect the amount DNA less than 10 -9 g

  14. Molecular Epidemiology of Mycobacterium Tuberculosis Strains in ...

    African Journals Online (AJOL)

    Doroudchi M, Kremer K, Basiri EA, Kadivar MR,. Van Soolingen D, Ghaderi AA. IS6110‑RFLP and spoligotyping of Mycobacterium tuberculosis isolates in Iran. Scand J Infect. Dis 2000;32:663‑8. 13. Farnia P, Masjedi MR, Mirsaeidi M, Mohammadi F,. Jallaledin‑Ghanavi, Vincent V, et al. Prevalence of Haarlem I and Beijing ...

  15. Mycobacterium bovis Infection of Red Fox, France.

    Science.gov (United States)

    Michelet, Lorraine; De Cruz, Krystel; Hénault, Sylvie; Tambosco, Jennifer; Richomme, Céline; Réveillaud, Édouard; Gares, Hélène; Moyen, Jean-Louis; Boschiroli, María Laura

    2018-06-01

    Mycobacterium bovis infection in wild red foxes was found in southern France, where livestock and other wildlife species are infected. Foxes frequently interact with cattle but have been underestimated as a reservoir of M. bovis. Our results suggest a possible role of the red fox in the epidemiology of bovine tuberculosis.

  16. Mycobacterium tuberculosis monoarthritis in a child

    Directory of Open Access Journals (Sweden)

    Rosenberg Alan M

    2008-09-01

    Full Text Available Abstract A child with isolated Mycobacterium tuberculosis monoarthritis, with features initially suggesting oligoarthritis subtype of juvenile idiopathic arthritis, is presented. This patient illustrates the need to consider the possibility of tuberculosis as the cause of oligoarthritis in high-risk pediatric populations even in the absence of a tuberculosis contact history and without evidence of overt pulmonary disease.

  17. Investigating Mycobacterium chelonae-abscessus Complex

    Centers for Disease Control (CDC) Podcasts

    2011-11-17

    Keith Simmon, scientist at Isentio US discusses research that was done while he was at ARUP laboratories, discusses a new classification of Mycobacterium chelonae-abscessus complex.  Created: 11/17/2011 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 11/22/2011.

  18. Safety assessment in primary Mycobacterium tuberculosis smear ...

    African Journals Online (AJOL)

    Introduction Tuberculosis (TB) is caused by Mycobacterium tuberculosis and is transmitted mainly through aerosolization of infected sputum which puts laboratory workers at risk in spite of the laboratory workersf risk of infection being at 3 to 9 times higher than the general public. Laboratory safety should therefore be ...

  19. Molecular Characterization of the Resistance of Mycobacterium ...

    African Journals Online (AJOL)

    Abstract. Purpose: To characterize the resistance of Mycobacterium tuberculosis to second line drugs using a line probe assay. Methods: ... Marne-la-Coquette,. France). Bacterial isolates contained in 500 µl of liquid culture were heat- inactivated at 95 °C for 30 min and then sonicated for 12 min. Finally, the suspension was ...

  20. Peritoneal tuberculosis due to Mycobacterium caprae

    Directory of Open Access Journals (Sweden)

    T. Nebreda

    2016-01-01

    Full Text Available The incidence of tuberculosis in humans due to Mycobacterium caprae is very low and is almost confined to Europe. We report a case of a previously healthy 41-year-old Moroccan with a 6 month history of abdominal pain, weight loss, fatigue and diarrhea. A diagnosis of peritoneal tuberculosis due to M. caprae was made.

  1. The epidemiology of Mycobacterium leprae: recent insight

    NARCIS (Netherlands)

    van Beers, S. M.; de Wit, M. Y.; Klatser, P. R.

    1996-01-01

    Leprosy is still a health problem in many countries. Because the causative organism, Mycobacterium leprae cannot be cultured in vitro, it is virtually impossible to assess exposure, and the onset of infection and disease. As a consequence, the chain of infection, considered as the relationships

  2. Modelling the Transitional Dynamics of Mycobacterium Tuberculosis ...

    African Journals Online (AJOL)

    The World Health Organization's targets of eliminating Tuberculosis (TB) by 2050 is challenged by the emergence and spread of drug resistance TB. However, the traditional mechanism of resistance is that of acquired resistance, whereby the mycobacterium Tuberculosis (MTB) strain develops mutations under selective ...

  3. Mitogen-activated protein kinases mediate Mycobacterium

    Indian Academy of Sciences (India)

    CD44, an adhesion molecule, has been reported to be a binding site for Mycobacterium tuberculosis (M. tuberculosis) in macrophages and it also mediates mycobacterial phagocytosis, macrophage recruitment and protective immunity against pulmonary tuberculosis in vivo. However, the signalling pathways that are ...

  4. Otomastoiditis Caused by Mycobacterium abscessus, the Netherlands

    NARCIS (Netherlands)

    van Ingen, Jakko; Looijmans, Frank; Mirck, Piet; Dekhuijzen, Richard; Boeree, Martin; van Soolingen, Dick

    2010-01-01

    To the Editor: Nontuberculous mycobacteria (NTM) are increasingly recognized as human pathogens (1). Otomastoiditis is a rare extrapulmonary NTM disease type first described in 1976; Mycobacterium chelonae-M. abscessus group bacteria, which are rapidly growing NTM, are the most frequent causative

  5. ELECTROPHORETIC MOBILITY OF MYCOBACTERIUM AVIUM COMPLEX ORGANISMS

    Science.gov (United States)

    The electrophoretic mobilities (EPMs) of thirty Mycobacterium avium Complex (MAC) organisms were measured. The EPMs of fifteen clinical isolates ranged from -1.9 to -5.0 µm cm V-1s-1, and the EPMs of fifteen environmental isolates ranged from -1...

  6. Chronic leg ulcer caused by Mycobacterium immunogenum

    NARCIS (Netherlands)

    Loots, Miriam A. M.; de Jong, Menno D.; van Soolingen, Dick; Wetsteyn, José C. F. M.; Faber, William R.

    2005-01-01

    Rare tropical skin diseases are seen more frequently in Western countries because of the increased popularity of visiting tropical regions. A 55-year-old white man developed a painless leg ulcer after traveling in Guatemala and Belize. A mycobacterium was cultured from a biopsy specimen and was

  7. Identification of Immunotopes against Mycobacterium leprae as ...

    African Journals Online (AJOL)

    Purpose: To determine the surface epitopes of Mycobacterium leprae (M. leprae) and evaluate their efficacy in the production of anti-M. leprae antibodies in an animal model. Methods: Blood samples were obtained from 34 patients suffering from lepromatous leprosy. Antibodies were obtained from the samples, ...

  8. Seroprevalence of Mycobacterium avium SSP paratuberculosis ...

    African Journals Online (AJOL)

    This study aimed to determine the seroprevalence of antibodies for Mycobacterium avium subspecies paratuberculosis (MAP) in dairy cattle in the Jimma zone of Ethiopia in 2011. A random sample of 29 herds was selected, and all mature cattle within these herds had a blood sample taken. Serum was tested in duplicate, ...

  9. Granulomatous lobular mastitis secondary to Mycobacterium fortuitum.

    Science.gov (United States)

    Kamyab, Armin

    2016-12-16

    Granulomatous lobular mastitis is a rare inflammatory disease of the breast of unknown etiology. Most present as breast masses in women of child-bearing age. A 29-year-old female presented with a swollen, firm and tender right breast, initially misdiagnosed as mastitis. Core needle biopsy revealed findings consistent with granulomatous lobular mastitis, and cultures were all negative for an infectious etiology. She was started on steroid therapy to which she initially responded well. A few weeks later she deteriorated and was found to have multiple breast abscesses. She underwent operative drainage and cultures grew Mycobacterium fortuitum . Granulomatous lobular mastitis is a rare inflammatory disease of the breast. The definitive diagnose entails a biopsy. Other causes of chronic or granulomatous mastitis should be ruled out, including atypical or rare bacteria such as Mycobacterium fortuitum . This is the first reported case of granulomatous mastitis secondary to Mycobacterium fortuitum . With pathologic confirmation of granulomatous mastitis, an infectious etiology must be ruled out. Atypical bacteria such as Mycobacterium fortuitum may not readily grow on cultures, as with our case. Medical management is appropriate, with surgical excision reserved for refractory cases or for drainage of abscesses.

  10. Occurrence and temporal variability of methyl tert-butyl ether (MTBE) and other volatile organic compounds in select sources of drinking water : results of the focused survey

    Science.gov (United States)

    Delzer, Gregory C.; Ivahnenko, Tamara

    2003-01-01

    The large-scale use of the gasoline oxygenate methyl tert-butyl ether (MTBE), and its high solubility, low soil adsorption, and low biodegradability, has resulted in its detection in ground water and surface water in many places throughout the United States. Studies by numerous researchers, as well as many State and local environmental agencies, have discovered high levels of MTBE in soils and ground water at leaking underground gasoline-storage-tank sites and frequent occurrence of low to intermediate levels of MTBE in reservoirs used for both public water supply and recreational boating.In response to these findings, the American Water Works Association Research Foundation sponsored an investigation of MTBE and other volatile organic compounds (VOCs) in the Nation's sources of drinking water. The goal of the investigation was to provide additional information on the frequency of occurrence, concentration, and temporal variability of MTBE and other VOCs in source water used by community water systems (CWSs). The investigation was completed in two stages: (1) reviews of available literature and (2) the collection of new data. Two surveys were associated with the collection of new data. The first, termed the Random Survey, employed a statistically stratified design for sampling source water from 954 randomly selected CWSs. The second, which is the focus of this report, is termed the Focused Survey, which included samples collected from 134 CWS source waters, including ground water, reservoirs, lakes, rivers, and streams, that were suspected or known to contain MTBE. The general intent of the Focused Survey was to compare results with the Random Survey and provide an improved understanding of the occurrence, concentration, temporal variability, and anthropogenic factors associated with frequently detected VOCs. Each sample collected was analyzed for 66 VOCs, including MTBE and three other ether gasoline oxygenates (hereafter termed gasoline oxygenates). As part of

  11. Enfermedad por Mycobacterium simiae y "Mycobacterium sherrisii" en la Argentina Disease due to Mycobacterium simiae and "Mycobacterium sherrisii" in Argentina

    Directory of Open Access Journals (Sweden)

    Lucía Barrera

    2010-08-01

    Full Text Available Se presenta información reunida retrospectivamente sobre casos de micobacteriosis originados por Mycobacterium simiae (n = 4 y "M. sherrisii" (n = 6. Los casos ocurrieron entre pacientes con sida (n = 6, historia de silicosis (n = 2 o tuberculosis previa (n = 1. Un caso se perdió luego de diagnosticado y nueve fueron tratados con esquemas terapéuticos basados en claritromicina, etambutol y quinolonas. La respuesta fue muy pobre: cinco pacientes fallecieron (cuatro eran HIV positivos, tres permanecieron crónicos y sólo uno curó. Estas micobacterias originaron 2.1% de los casos de micobacteriosis registrados en un período de ocho años. La distinción de estas micobacterias raras de otras más frecuentes por métodos moleculares rápidos, parece ser clínicamente útil para advertir sobre la dificultad que puede presentar el tratamiento. Sin embargo, la diferenciación genotípica entre M. simiae y "M. sherrisii" parecería no ser clínicamente relevante, dado que no quedaron expuestas características que distingan a los pacientes afectados por los dos microorganismos tan estrechamente relacionados.A revision of mycobacterial disease due to M simiae (n = 4 and "M. sherrisii" (n = 6 identified during an eight-year period is presented. Cases occurred among patients with AIDS (n = 6, previous history of silicosis (n = 2 or tuberculosis (n = 2. One case was lost to follow-up and the remaining nine responded poorly to chemotherapy based on clarithromycin, ethambutol and fluoroquinolones. Five patients died of whom four were HIV-positive, three remained chronic and one was cured. These microorganisms originated 2.1% of mycobacterioses cases detected in an eight-year period. Timely identification of this group of uncommon mycobacteria by molecular methods seems to be clinically relevant in order to warn of difficulties inherent to the treatment. However, the distinction between both closely related microorganisms might not be crucial for case

  12. Cryopreservation of Mycobacterium bovis isolates

    Directory of Open Access Journals (Sweden)

    Cássia Yumi Ikuta

    2016-11-01

    Full Text Available Research, development of new biotechnological methods, diagnostic tests, confirmation of results, and reinvestigations are possible because of the availability of well-preserved living organisms maintained without any changes. Cryopreservation is a simpler, more reliable and long-term stable method for culture maintenance. Storage temperature and composition of the suspending vehicle are factors that affect the viability of mycobacterial strains. Three vehicles and three storage temperatures were evaluated to define a suitable cryoprotective medium for the preservation of Mycobacterium bovis strains. Colonies of sixteen M. bovis isolates were used to prepare the suspensions, which were then added to three vehicles: sterile 0.85% saline solution (SS, Middlebrook 7H9 broth (7H9, and Middlebrook 7H9 broth with sodium pyruvate (7H9p replacing glycerol. Aliquots of these suspensions were frozen by three different methods, directly in the -20°C freezer, directly in the -80°C freezer, and at -196°C by immersion in liquid nitrogen (LN. The frozen aliquots were thawed at room temperature after 45, 90 and 120 days. Mycobacterial viability was assessed by counting the living cells on plates of Stonebrink medium before and after the freezing procedure. Storage at -20°C exhibited a lower recovery of M. bovis compared to storage at -80°C (Dunn’s test, p=0.0018 and LN (Dunn’s test, p=0.0352. There was no statistically significant difference between storage at -80°C and in LN (Dunn’s test, p=0.1403, yet -80°C showed better results than LN. All three suspending vehicles showed no statistically significant difference in terms of viability (Friedman’s test, p=0.7765. Given the low loss proportion of 5% during storage at -20°C and the high cost equipment required for storage at -80°C and LN, we recommend storage at -20°C or -80°C, when this is available, for preservation of M. bovis field strains.

  13. Mycobacterium talmoniae sp. nov., a slowly growing mycobacterium isolated from human respiratory samples.

    Science.gov (United States)

    Davidson, Rebecca M; DeGroote, Mary Ann; Marola, Jamie L; Buss, Sarah; Jones, Victoria; McNeil, Michael R; Freifeld, Alison G; Elaine Epperson, L; Hasan, Nabeeh A; Jackson, Mary; Iwen, Peter C; Salfinger, Max; Strong, Michael

    2017-08-01

    A novel slowly growing, non-chromogenic species of the class Actinobacteria was isolated from a human respiratory sample in Nebraska, USA, in 2012. Analysis of the internal transcribed spacer sequence supported placement into the genus Mycobacterium with high sequence similarity to a previously undescribed strain isolated from a patient respiratory sample from Oregon, USA, held in a collection in Colorado, USA, in 2000. The two isolates were subjected to phenotypic testing and whole genome sequencing and found to be indistinguishable. The bacteria were acid-fast stain-positive, rod-shaped and exhibited growth after 7-10 days on solid media at temperatures ranging from 25 to 42°C. Colonies were non-pigmented, rough and slightly raised. Analyses of matrix-assisted laser desorption ionization time-of-flight profiles showed no matches against a reference library of 130 mycobacterial species. Full-length 16S rRNA gene sequences were identical for the two isolates, the average nucleotide identity (ANI) between their genomes was 99.7 % and phylogenetic comparisons classified the novel mycobacteria as the basal most species in the slowly growing Mycobacterium clade. Mycobacterium avium is the most closely related species based on rpoB gene sequence similarity (92 %), but the ANI between the genomes was 81.5 %, below the suggested cut-off for differentiating two species (95 %). Mycolic acid profiles were more similar to M. avium than to Mycobacterium simiae or Mycobacterium abscessus. The phenotypic and genomic data support the conclusion that the two related isolates represent a novel Mycobacterium species for which the name Mycobacterium talmoniae sp. nov. is proposed. The type strain is NE-TNMC-100812T (=ATCC BAA-2683T=DSM 46873T).

  14. La fibroscopie digestive haute chez 2795 patients au centre hospitalier universitaire-campus de Lomé: les particularités selon le sexe

    Science.gov (United States)

    Lawson-Ananissoh, Laté Mawuli; Bouglouga, Oumboma; Bagny, Aklesso; Kaaga, Laconi; Redah, Datouda

    2014-01-01

    Introduction Notre étude consistera à rapporter les indications et les lésions objectivées à la fibroscopie digestive haute et relever les particularités selon le sexe. Méthodes Étude rétrospective, descriptive sur des résultats de compte-rendu de la fibroscopie digestive haute menée en unité d'endoscopie digestive du service d'hépato-gastro-entérologie du CHU Campus de Lomé du 15 Mai 2009 au 31 Décembre 2013. Résultats La fibroscopie digestive haute a été réalisée chez 2795 patients dont 1188 hommes et 1607 femmes. L’âge moyen était de 40,65 ans (Extrêmes: 5 et 93 ans). La fibroscopie digestive haute était normale chez les femmes que chez les hommes avec une différence statistiquement significative (p = 0,000). Les principales indications étaient: les épigastralgies chez les femmes (p = 0,000); les hémorragies digestives hautes (p = 0,000) et l'hypertension portale (p = 0,000) chez les hommes; 3485 lésions pathologiques ont été observées. La pathologie inflammatoire prédominait (56,3%), la pathologie ulcéreuse (13,89%), la pathologie tumorale (2,01%). Les varices et la candidose œsophagiennes étaient significativement notées chez les hommes. Les ulcérations gastriques (p = 0,000), le reflux biliaire duodéno-gastrique (p = 0,017) étaient plus retrouvés chez les femmes et la gastropathie hypertensive beaucoup plus chez les hommes (p = 0,000). Que les lésions duodénales soient inflammatoires ou ulcéreuses associées ou non à une sténose bulbaire, elles étaient plus fréquentes chez les hommes. Conclusion De manière générale, il y avait une prédominance des lésions inflammatoires chez les femmes, les lésions tumorales et ulcéreuses chez les hommes PMID:25852805

  15. Bone marrow infection with mycobacterium fortuitum in a diabetic patient

    International Nuclear Information System (INIS)

    Satti, L.; Abbasi, S.; Sattar, A.; Ikram, A.; Manzar, M.A.; Khalid, M.M.

    2011-01-01

    Incidence and prevalence of Mycobacterium fortuitum infection vary greatly by location and death is very rare except in disseminated disease in immunocompromised individuals. We present what we believe is the first case of bone marrow infection with Mycobacterium fortuitum in an HIV negative patient. Bone marrow examination revealed presence of numerous acid fast bacilli which were confirmed as Mycobacterium fortuitum on culture and by molecular analysis. Patient was managed successfully with amikacin and ciprofloxacin. (author)

  16. L’hybridation interspécifique chez les champignons phytopathogènes à l’origine de nouvelles maladies

    OpenAIRE

    Frey, Pascal

    2009-01-01

    Mécanisme évolutif bien connu chez les plantes, l’hybridation interspécifique a été relativement peu étudiée dans certains groupes taxonomiques, comme les champignons. Chez les champignons phytopathogènes, l’hybridation entre une espèce indigène et une espèce exotique peut pourtant conduire à l’émergence de nouvelles maladies des plantes.

  17. Facteurs prédictifs de la réponse à la CERA chez les hémodialysés ...

    African Journals Online (AJOL)

    Facteurs prédictifs de la réponse à la CERA chez les hémodialysés chroniques naïfs de traitement par agent stimulant l'érythropoïèse. ... Il s'agit une étude prospective mono centrique faite au sein d'une population d' hémodialysés chroniques. ... L'anémie est une complication majeure chez les hémodialysés chroniques.

  18. Mycobacterium komaniense sp. nov., a rapidly growing non-tuberculous Mycobacterium species detected in South Africa.

    Science.gov (United States)

    Gcebe, Nomakorinte; Rutten, Victor P M G; van Pittius, Nicolaas Gey; Naicker, Brendon; Michel, Anita L

    2018-05-01

    Some species of non-tuberculous mycobacteria (NTM) have been reported to be opportunistic pathogens of animals and humans. Recently there has been an upsurge in the number of cases of NTM infections, such that some NTM species are now recognized as pathogens of humans and animals. From a veterinary point of view, the major significance of NTM is the cross-reactive immune response they elicit against Mycobacterium bovis antigens, leading to misdiagnosis of bovine tuberculosis. Four NTM isolates were detected from a bovine nasal swab, soil and water, during an NTM survey in South Africa. These were all found using 16S rRNA gene sequence analysis to be closely related to Mycobacterium moriokaense. The isolates were further characterised by sequence analysis of the partial fragments of hsp65, rpoB and sodA. The genome of the type strain was also elucidated. Gene (16S rRNA, hsp65, rpoB and sodA) and protein sequence data analysis of 6 kDa early secretory antigenic target (ESAT 6) and 10 kDa culture filtrate protein (CFP-10) revealed that these isolates belong to a unique Mycobacterium species. Differences in phenotypic and biochemical traits between the isolates and closely related species further supported that these isolates belong to novel Mycobacterium species. We proposed the name Mycobacterium komaniense sp. nov. for this new species. The type strain is GPK 1020 T (=CIP 110823T=ATCC BAA-2758).

  19. Mycobacterium ahvazicum sp. nov., the nineteenth species of the Mycobacterium simiae complex.

    Science.gov (United States)

    Bouam, Amar; Heidarieh, Parvin; Shahraki, Abodolrazagh Hashemi; Pourahmad, Fazel; Mirsaeidi, Mehdi; Hashemzadeh, Mohamad; Baptiste, Emeline; Armstrong, Nicholas; Levasseur, Anthony; Robert, Catherine; Drancourt, Michel

    2018-03-07

    Four slowly growing mycobacteria isolates were isolated from the respiratory tract and soft tissue biopsies collected in four unrelated patients in Iran. Conventional phenotypic tests indicated that these four isolates were identical to Mycobacterium lentiflavum while 16S rRNA gene sequencing yielded a unique sequence separated from that of M. lentiflavum. One representative strain AFP-003 T was characterized as comprising a 6,121,237-bp chromosome (66.24% guanosine-cytosine content) encoding for 5,758 protein-coding genes, 50 tRNA and one complete rRNA operon. A total of 2,876 proteins were found to be associated with the mobilome, including 195 phage proteins. A total of 1,235 proteins were found to be associated with virulence and 96 with toxin/antitoxin systems. The genome of AFP-003 T has the genetic potential to produce secondary metabolites, with 39 genes found to be associated with polyketide synthases and non-ribosomal peptide syntases and 11 genes encoding for bacteriocins. Two regions encoding putative prophages and three OriC regions separated by the dnaA gene were predicted. Strain AFP-003 T genome exhibits 86% average nucleotide identity with Mycobacterium genavense genome. Genetic and genomic data indicate that strain AFP-003 T is representative of a novel Mycobacterium species that we named Mycobacterium ahvazicum, the nineteenth species of the expanding Mycobacterium simiae complex.

  20. Mycobacterium bovis and Other Uncommon Members of the Mycobacterium tuberculosis Complex.

    Science.gov (United States)

    Esteban, Jaime; Muñoz-Egea, Maria-Carmen

    2016-12-01

    Since its discovery by Theobald Smith, Mycobacterium bovis has been a human pathogen closely related to animal disease. At present, M. bovis tuberculosis is still a problem of importance in many countries and is considered the main cause of zoonotic tuberculosis throughout the world. Recent development of molecular epidemiological tools has helped us to improve our knowledge about transmission patterns of this organism, which causes a disease indistinguishable from that caused by Mycobacterium tuberculosis. Diagnosis and treatment of this mycobacterium are similar to those for conventional tuberculosis, with the important exceptions of constitutive resistance to pyrazinamide and the fact that multidrug-resistant and extremely drug-resistant M. bovis strains have been described. Among other members of this complex, Mycobacterium africanum is the cause of many cases of tuberculosis in West Africa and can be found in other areas mainly in association with immigration. M. bovis BCG is the currently available vaccine for tuberculosis, but it can cause disease in some patients. Other members of the M. tuberculosis complex are mainly animal pathogens with only exceptional cases of human disease, and there are even some strains, like "Mycobacterium canettii," which is a rare human pathogen that could have an important role in the knowledge of the evolution of tuberculosis in the history.

  1. 21 CFR 866.3370 - Mycobacterium tuberculosis immunofluorescent reagents.

    Science.gov (United States)

    2010-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents... used to identify Mycobacterium tuberculosis directly from clinical specimens. The identification aids...

  2. A single or multistage mycobacterium avium subsp. paratuberculosis subunit vaccine

    DEFF Research Database (Denmark)

    2014-01-01

    The present invention provides one or more immunogenic polypeptides for use in a preventive or therapeutic vaccine against latent or active infection in a human or animal caused by a Mycobacterium species, e.g. Mycobacterium avium subsp. paratuberculosis. Furthermore a single or multi-phase vaccine...... comprising the one or more immunogenic polypeptides is provided for administration for the prevention or treatment of infection with a Mycobacterium species, e.g. Mycobacterium avium subsp. paratuberculosis. Additionally, nucleic acid vaccines, capable of in vivo expression of the multi-phase vaccine...

  3. Doppler transcranien au cours de la drépanocytose chez l'enfant Malagasy

    Science.gov (United States)

    Herinirina, Nicolas Fanantenana; Rajaonarison, Lova Hasina Ny Ony Narindra; Herijoelison, Andry Roussel; Rakoto, Olivat Aimée Alson; Ahmad, Ahmad

    2016-01-01

    Introduction Le doppler transcrânien est un outil efficace permettant de dépister les enfants drépanocytaires à risque d'AVC. Méthodes Nous avons réalisé une étude descriptive transversale sur des enfants Malagasy âgés entre 24 mois et 15 ans (groupe 1: 57 drépanocytaires, groupe 2: 43 témoins) afin d’évaluer le profil vélocimétrique des artères cérébrales chez les drépanocytaires. Un examen Doppler transcrânien a été réalisé avec étude des flux sanguins cérébraux chez les enfants des deux groupes. Résultats Pour les sujets drépanocytaires, la vitesse moyenne (VM) de l'artère cérébrale moyenne était de 100,9 ± 26,8 cm/s, l'indice de pulsatilité (IP) de 0,73 ± 0,20, la différence entre les artères cérébrales moyennes droite et gauche (ACMr) de 19,8 ± 21,5 cm/s, le rapport des vitesses de l'artère cérébrale antérieure/artère cérébrale moyenne (ACA/ACM) de 0,7 ± 0,2. Pour les enfants non drépanocytaires, VM: 80,6 ± 19,3 cm/s, IP: 0,79 ± 0,14, ACMr: 17 ± 20,1 cm/s, ACA/ACM: 0,8 ± 0,2. La vélocité des enfants drépanocytaires était supérieure au groupe contrôle. Les vitesses ont été corrélées avec le taux d'hémoglobine et l’âge et non pas avec le sexe et le volume globulaire moyen. Conclusion Les vitesses circulatoires cérébrales sont élevées chez les drépanocytaires que les enfants non drépanocytaires et sont influencées par le taux d'hémoglobine et l’âge. PMID:27516829

  4. Infection caused by Mycobacterium tuberculosis.

    Science.gov (United States)

    Peloquin, C A; Berning, S E

    1994-01-01

    To update readers on the clinical management of infections caused by Mycobacterium tuberculosis, to provide a general description of the organism, culture and susceptibility testing, and clinical manifestations of the disease, and to provide several aspects of the treatment of the disease, including historical perspective, current approaches, and research opportunities for the future. The current medical literature, including abstracts presented at recent international meetings, is reviewed. References were identified through MEDLINE, MEDLARS II, Current Contents, and published meeting abstracts. Data regarding the epidemiology, clinical manifestations, culture and susceptibility testing, and treatment of tuberculosis are cited. Specific attention has been focused on the clinical management of patients with noncontagious infection and potentially contagious active disease (TB) caused by M. tuberculosis. Information contributing to the discussion of the topics selected by the authors is reviewed. Data supporting and disputing specific conclusions are presented. The incidence of TB is increasing in the US, despite the fact that available technologies are capable of controlling the vast majority of existing cases. Fueling the fire is the problem of coinfection with HIV and M. tuberculosis. Very few drugs are available for the treatment of TB, and few of these approach the potency of isoniazid and rifampin. Preventive therapy of patients exposed to multiple-drug-resistant M. tuberculosis (MDR-TB) is controversial and of unknown efficacy. Treatment of active disease caused by MDR-TB requires up to four times longer, is associated with increased toxicity, and is far less successful than the treatment of drug-susceptible TB. Strategies for the management of such cases are presented. The rising incidence of TB in the US reflects a breakdown in the healthcare systems responsible for controlling the disease, which reflects the past budgetary reductions. Although TB control

  5. [Identification and drug susceptibility testing of Mycobacterium thermoresistibile and Mycobacterium elephantis isolated from a cow with mastitis].

    Science.gov (United States)

    Li, W B; Ji, L Y; Xu, D L; Liu, H C; Zhao, X Q; Wu, Y M; Wan, K L

    2018-05-10

    Objective: To understand the etiological characteristics and drug susceptibility of Mycobacterium thermoresistibile and Mycobacterium elephantis isolated from a cow with mastitis and provide evidence for the prevention and control of infectious mastitis in cows. Methods: The milk sample was collected from a cow with mastitis, which was pretreated with 4 % NaOH and inoculated with L-J medium for Mycobacterium isolation. The positive cultures were initially identified by acid-fast staining and multi-loci PCR, then Mycobacterium species was identified by the multiple loci sequence analysis (MLSA) with 16S rRNA , hsp65 , ITS and SodA genes. The drug sensitivity of the isolates to 27 antibiotics was tested by alamar blue assay. Results: Two anti-acid stain positive strains were isolated from the milk of a cow with mastitis, which were identified as non- tuberculosis mycobacterium by multi-loci PCR, and multi-loci nucleic acid sequence analysis indicated that one strain was Mycobacterium thermoresistibile and another one was Mycobacterium elephantis . The results of the drug susceptibility test showed that the two strains were resistant to most antibiotics, including rifampicin and isoniazid, but they were sensitive to amikacin, moxifloxacin, levofloxacin, ethambutol, streptomycin, tobramycin, ciprofloxacin and linezolid. Conclusions: Mycobacterium thermoresistibile and Mycobacterium elephantis were isolated in a cow with mastitis and the drug susceptibility spectrum of the pathogens were unique. The results of the study can be used as reference for the prevention and control the infection in cows.

  6. Multifaceted role of lipids in Mycobacterium leprae.

    Science.gov (United States)

    Kaur, Gurkamaljit; Kaur, Jagdeep

    2017-03-01

    Mycobacterium leprae must adopt a metabolic strategy and undergo various metabolic alterations upon infection to survive inside the human body for years in a dormant state. A change in lipid homeostasis upon infection is highly pronounced in Mycobacterium leprae. Lipids play an essential role in the survival and pathogenesis of mycobacteria. Lipids are present in several forms and serve multiple roles from being a source of nutrition, providing rigidity, evading the host immune response to serving as virulence factors, etc. The synthesis and degradation of lipids is a highly regulated process and is the key to future drug designing and diagnosis for mycobacteria. In the current review, an account of the distinct roles served by lipids, the mechanism of their synthesis and degradation has been elucidated.

  7. ZINC ET PROFIL IMMUNO-INFLAMMATOIRE CHEZ LES ENFANTS ET LES ADOLESCENTS DIABETIQUES DE TYPE 1

    OpenAIRE

    BESTAOUI, Abdelaziz

    2014-01-01

    Introduction : le diabète de type 1 (DT1) est une maladie autoimmune qui résulte de la destruction progressive et sélective des cellules-bêta pancréatiques. Objectifs : Ce travail consiste à déterminer les nivaux de zinc apporté par l’alimentation et de mesurer sa concentration sérique chez les diabétiques de type 1 et les sujets sains, contrôles. But : Montrer le rôle immuno-modulateur du zinc dans le processus d’auto-immunité inflammatoire au cours de DT1. Matériels et méthodes : t...

  8. Développement folliculaire ovarien et ovulation chez les mammifères

    OpenAIRE

    Monniaux , Danielle; Caraty , Alain; Clement , Frederique; Dalbiès-Tran , Rozenn; Dupont , J.; Fabre , Stéphane; Gérard , N.; Mermillod , Pascal; Monget , Philippe; Uzbekova , Svetlana

    2009-01-01

    Cette revue présente l’état des connaissances sur la folliculogenèse et l’ovulation chez les mammifères. La folliculogenèse basale est une phase de croissance folliculaire lente, au cours de laquelle l’ovocyte acquiert la compétence méiotique. La folliculogenèse terminale est une phase de développement rapide, au cours de laquelle le follicule ovulatoire est sélectionné et termine sa maturation, tandis que l’ovocyte acquiert la compétence au développement. La revue décrit les différents chang...

  9. Hallucination chez Flaubert : poétique de la perception

    Directory of Open Access Journals (Sweden)

    Tomoko Hashimoto

    2009-01-01

    Full Text Available Notre étude vise à montrer dans le cadre d’une poétique du discours réaliste la manière dont l’« hallucination » fonctionne, se construit et trouve sa signification chez Flaubert. Par quels procédés fait-il surgir des mots le caractère éphémère des images et l’intensité de leur perception ?Notre étude se développera en une forme de triptyque, où le contexte, l’avant-texte et le texte seront examinés. Mais, ces trois points constituant ensemble l’œuvre de Flaubert, nous ne les séparerons pas à...

  10. La digestion chez les camélidés ; comparaison avec les ruminants

    OpenAIRE

    Jouany, J Pierre

    2000-01-01

    Les études sur la digestion et le métabolisme des camélidés ont bénéficié au cours des quinze dernières années des progrès techniques et méthodologiques issus des travaux conduits chez les ruminants. On dispose aujourd’hui d’éléments scientifiques fiables qui permettent de comparer les aptitudes digestives et métaboliques respectives de ces deux types d’animaux. L’anatomie des pré-estomacs ainsi que le comportement alimentaire des animaux sont très différents entre camélidés et ruminants. De ...

  11. Nitazoxanide is active against Mycobacterium leprae

    Science.gov (United States)

    Bailey, Mai Ann; Na, Hana; Duthie, Malcolm S.; Gillis, Thomas P.; Lahiri, Ramanuj

    2017-01-01

    Nitazoxanide (NTZ) is an anti-parasitic drug that also has activity against bacteria, including Mycobacterium tuberculosis. Our data using both radiorespirometry and live-dead staining in vitro demonstrate that NTZ similarly has bactericidal against M. leprae. Further, gavage of M. leprae-infected mice with NTZ at 25mg/kg provided anti-mycobacterial activity equivalent to rifampicin (RIF) at 10 mg/kg. This suggests that NTZ could be considered for leprosy treatment. PMID:28850614

  12. Comparative Mycobacteriology of the Mycobacterium tuberculosis complex

    OpenAIRE

    Gordon, Stephen V.; Behr, Marcel A.

    2015-01-01

    The Mycobacterium tuberculosis complex (MTBC) is a group of highly genetically related pathogens that cause tuberculosis (TB) in mammalian species. However, the very name of the complex underlines the fact that our knowledge of these pathogens is dominated by studies on the human pathogen, M. tuberculosis. Of course this is entirely justified; M. tuberculosis is a major global pathogen that exacts a horrendous burden in terms of mortality and morbidity so it is appropriate that it is...

  13. Inactivation of Mycobacterium paratuberculosis and Mycobacterium tuberculosis in fresh soft cheese by gamma radiation

    International Nuclear Information System (INIS)

    Badr, Hesham M.

    2011-01-01

    The effectiveness of gamma irradiation on the inactivation of Mycobacterium paratuberculosis, Mycobacterium bovis and Mycobacterium tuberculosis in fresh soft cheese that prepared from artificially inoculated milk samples was studied. Irradiation at dose of 2 kGy was sufficient for the complete inactivation of these mycobacteria as they were not detected in the treated samples during storage at 4±1 o C for 15 days. Moreover, irradiation of cheese samples, that were prepared from un-inoculated milk, at this effective dose had no significant effects on their gross composition and contents from riboflavin, niacin and pantothenic acid, while significant decreases in vitamin A and thiamin were observed. In addition, irradiation of cheese samples had no significant effects on their pH and nitrogen fractions contents, except for the contents of ammonia, which showed a slight, but significant, increases due to irradiation. The analysis of cheese fats indicated that irradiation treatment induced significant increase in their oxidation parameters and contents from free fatty acids; however, the observed increases were relatively low. On the other hand, irradiation of cheese samples induced no significant alterations on their sensory properties. Thus, irradiation dose of 2 kGy can be effectively applied to ensure the safety of soft cheese with regards to these harmful mycobacteria. - Highlights: → We examined the effectiveness of gamma irradiation on inactivation of Mycobacterium paratuberculosis, Mycobacterium bovis and Mycobacterium tuberculosis in fresh soft cheese. → Irradiation at dose of 2 kGy was sufficient for complete inactivation of these mycobacteria. → Irradiation of cheese samples induced no significant alterations on their sensory properties.

  14. Inactivation of Mycobacterium paratuberculosis and Mycobacterium tuberculosis in fresh soft cheese by gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Badr, Hesham M., E-mail: heshambadr_aea@yahoo.co.uk [Atomic Energy Authority, Nuclear Research Center, Abou Zaabal, P.O. Box 13759 Cairo (Egypt)

    2011-11-15

    The effectiveness of gamma irradiation on the inactivation of Mycobacterium paratuberculosis, Mycobacterium bovis and Mycobacterium tuberculosis in fresh soft cheese that prepared from artificially inoculated milk samples was studied. Irradiation at dose of 2 kGy was sufficient for the complete inactivation of these mycobacteria as they were not detected in the treated samples during storage at 4{+-}1 {sup o}C for 15 days. Moreover, irradiation of cheese samples, that were prepared from un-inoculated milk, at this effective dose had no significant effects on their gross composition and contents from riboflavin, niacin and pantothenic acid, while significant decreases in vitamin A and thiamin were observed. In addition, irradiation of cheese samples had no significant effects on their pH and nitrogen fractions contents, except for the contents of ammonia, which showed a slight, but significant, increases due to irradiation. The analysis of cheese fats indicated that irradiation treatment induced significant increase in their oxidation parameters and contents from free fatty acids; however, the observed increases were relatively low. On the other hand, irradiation of cheese samples induced no significant alterations on their sensory properties. Thus, irradiation dose of 2 kGy can be effectively applied to ensure the safety of soft cheese with regards to these harmful mycobacteria. - Highlights: > We examined the effectiveness of gamma irradiation on inactivation of Mycobacterium paratuberculosis, Mycobacterium bovis and Mycobacterium tuberculosis in fresh soft cheese. > Irradiation at dose of 2 kGy was sufficient for complete inactivation of these mycobacteria. > Irradiation of cheese samples induced no significant alterations on their sensory properties.

  15. Les Cicatrices Retractiles Post-Brulures Du Membre Inferieur Chez L’Enfant

    Science.gov (United States)

    Sankale, A.A.; Manyacka Ma Nyemb, P.; Coulibaly, N.F.; Ndiaye, A.; Ndoye, M.

    2010-01-01

    Summary Il s'agit d'une étude faisant ressortir les aspects épidémiologiques, cliniques et thérapeutiques des séquelles de brûlures du membre inférieur chez l'enfant, à propos de 42 cas colligés au service de chirurgie infantile de l'Hôpital Aristide Le Dantec (Sénégal). L'âge moyen retrouvé est de 5 ans et 3 mois, et le sex-ratio garçons/filles de 1,8/1. La brûlure thermique est causée par une flamme dans 33% des cas, par un liquide chaud dans 21% des cas, et par des braises dans 21% des cas. Les cicatrices rétractiles intéressent le genou et le creux poplité dans 47% des cas et le pied dans 45% des cas. Elles sont bilatérales dans 21% des cas, et concernent une autre localisation associée dans 21% des cas. Quant aux brides, 21% ont bénéficié d'une chirurgie, avec un délai moyen de 3 ans et 2 mois après la brûlure. Cette procédure chirurgicale consiste en une plastie en Z dans 91% des cas, à laquelle est associée une greffe de peau dans 54% des cas. Une rééducation fonctionnelle est pratiquée chez 54% des opérés. Parallèlement aux données de la littérature, nos résultats montrent que l'optimisation de la prise en charge passe par une meilleure prévention des accidents domestiques et une bonne codification thérapeutique. PMID:21991202

  16. Prise en charge de l’infection gonococcique chez les adultes et les jeunes

    Science.gov (United States)

    Pogany, Lisa; Romanowski, Barbara; Robinson, Joan; Gale-Rowe, Margaret; Latham-Carmanico, Cathy; Weir, Christine; Wong, Tom

    2015-01-01

    Résumé Objectif Présenter des recommandations sur la prise en charge de l’infection gonococcique chez les adultes et les jeunes. Qualité des données Les recommandations thérapeutiques des lignes directrices canadiennes sur les infections transmissibles sexuellement reposent sur une recherche documentaire de même que sur des catégories de recommandations et des niveaux de qualité de données déterminés par au moins 2 évaluateurs. Les recommandations ont été revues par des pairs et sont en instance d’approbation par le groupe de travail d’experts. Message principal Les nouvelles recommandations portant sur la prise en charge de l’infection gonococcique chez les adultes et les jeunes préconisent les cultures à titre d’outil diagnostique lorsqu’elles sont pratiques, le traitement par antibiothérapie combinée (ceftriaxone associée à l’azithromycine) et le signalement sans délai de tous les cas dont le traitement a échoué aux autorités de santé publique. Conclusion Si elles sont suivies, ces nouvelles recommandations pourraient réduire l’échec thérapeutique, contribuer à une surveillance plus étroite des tendances à la résistance de Neisseria gonorrhoeae aux antibiotiques et contribuer à prévenir la transmission de gonorrhée résistante à plusieurs médicaments.

  17. A Dermal Piercing Complicated by Mycobacterium fortuitum

    Science.gov (United States)

    Scroggins-Markle, Leslie; Kelly, Brent

    2013-01-01

    Background. Dermal piercings have recently become a fashion symbol. Common complications include hypertrophic scarring, rejection, local infection, contact allergy, and traumatic tearing. We report a rare case of Mycobacterium fortuitum following a dermal piercing and discuss its medical implications and treatments. Case. A previously healthy 19-year-old woman presented complaining of erythema and edema at the site of a dermal piercing on the right fourth dorsal finger. She was treated with a 10-day course of trimethoprim-sulfamethoxazole and one course of cephalexin by her primary care physician with incomplete resolution. The patient stated that she had been swimming at a local water park daily. A punch biopsy around the dermal stud was performed, and cultures with sensitivities revealed Mycobacterium fortuitum. The patient was treated with clarithromycin and ciprofloxacin for two months receiving full resolution. Discussion. Mycobacterium fortuitum is an infrequent human pathogen. This organism is a Runyon group IV, rapidly growing nontuberculous mycobacteria, often found in water,soil, and dust. Treatment options vary due to the size of the lesion. Small lesions are typically excised, while larger lesions require treatment for 2–6 months with antibiotics. We recommend a high level of suspicion for atypical mycobacterial infections in a piercing resistant to other therapies. PMID:24073343

  18. A Dermal Piercing Complicated by Mycobacterium fortuitum

    Directory of Open Access Journals (Sweden)

    Trisha Patel

    2013-01-01

    Full Text Available Background. Dermal piercings have recently become a fashion symbol. Common complications include hypertrophic scarring, rejection, local infection, contact allergy, and traumatic tearing. We report a rare case of Mycobacterium fortuitum following a dermal piercing and discuss its medical implications and treatments. Case. A previously healthy 19-year-old woman presented complaining of erythema and edema at the site of a dermal piercing on the right fourth dorsal finger. She was treated with a 10-day course of trimethoprim-sulfamethoxazole and one course of cephalexin by her primary care physician with incomplete resolution. The patient stated that she had been swimming at a local water park daily. A punch biopsy around the dermal stud was performed, and cultures with sensitivities revealed Mycobacterium fortuitum. The patient was treated with clarithromycin and ciprofloxacin for two months receiving full resolution. Discussion. Mycobacterium fortuitum is an infrequent human pathogen. This organism is a Runyon group IV, rapidly growing nontuberculous mycobacteria, often found in water,soil, and dust. Treatment options vary due to the size of the lesion. Small lesions are typically excised, while larger lesions require treatment for 2–6 months with antibiotics. We recommend a high level of suspicion for atypical mycobacterial infections in a piercing resistant to other therapies.

  19. Methyl tert-butyl ether (MTBE) detected in abnormally high concentrations in postmortem blood and urine from two persons found dead inside a car containing a gasoline spill.

    Science.gov (United States)

    Karinen, Ritva; Vindenes, Vigdis; Morild, Inge; Johnsen, Lene; Le Nygaard, Ilah; Christophersen, Asbjørg S

    2013-09-01

    Two deep frozen persons, a female and a male, were found dead in a car. There had been an explosive fire inside the car which had extinguished itself. On the floor inside the car were large pools of liquid which smelled of gasoline. The autopsy findings and routine toxicological analyses could not explain the cause of death. Carboxyhemoglobin levels in the blood samples were gasoline as a fuel oxygenate. Gasoline poisoning is likely to be the cause of the death in these two cases, and MTBE can be a suitable marker of gasoline exposure, when other volatile components have vaporized. © 2013 American Academy of Forensic Sciences.

  20. Phylogenetic analysis of vitamin B12-related metabolism in Mycobacterium tuberculosis

    OpenAIRE

    Young, Douglas B.; Comas, I?aki; de Carvalho, Luiz P. S.

    2015-01-01

    Comparison of genome sequences from clinical isolates of Mycobacterium tuberculosis with phylogenetically-related pathogens Mycobacterium marinum, Mycobacterium kansasii, and Mycobacterium leprae reveals diversity amongst genes associated with vitamin B12-related metabolism. Diversity is generated by gene deletion events, differential acquisition of genes by horizontal transfer, and single nucleotide polymorphisms (SNPs) with predicted impact on protein function and transcriptional regulation...

  1. L’hybridation interspécifique et l’hétérosis chez les arbres forestiers

    OpenAIRE

    Pâques E., Luc

    2011-01-01

    L’hybridation interspécifique se rencontre fréquemment chez les arbres forestiers et intéressent les chercheurs dans des contextes très différents : introgression dans les aires naturelles des espèces, pollution des pools génétiques autochtones par des espèces/variétés introduites…. Elle est aussi valorisée en amélioration génétique en vue de la création variétale. Ce dernier aspect constitue le cœur de nos activités et de notre projet de recherche. Etudiés depuis longtemps chez les plantes...

  2. Sarcome à cellules claires du rein : À propos d’un cas chez un jeune de 17 ans

    Science.gov (United States)

    Mazdar, Adil; Sakel, Adil Ait; Essatara, Younes; Beddouche, Ali; Elsayegh, Hachem; Iken, Ali; Benslimane, Lounis; Nouini, Yassine

    2014-01-01

    Résumé Le sarcome à cellules claires du rein (SCCR) se voit très rarement chez les jeunes. Il est caractérisé par une évolution agressive marquée par un taux élevé de récidive et de mortalité. Nous rapportons le cas d’un SCCR chez un patient de 17 ans et nous discutons de son apport et de son intérêt médical en vue d’une bonne prise en charge thérapeutique. L’agressivité du SCCR et la prolifération de métastases surtout osseuses impliquent qu’il ne faut pas méconnaître ce diagnostic afin de mettre en place un traitement adapté. PMID:24940474

  3. Mycobacterium marinum infections in Denmark from 2004 to 2017

    DEFF Research Database (Denmark)

    Holden, Inge K.; Kehrer, Michala; Andersen, Aase B.

    2018-01-01

    Mycobacterium marinum (M. marinum) is a slowly growing nontuberculous mycobacterium. The incidence of M. marinum infections in Denmark is unknown. We conducted a retrospective nationwide study including all culture confirmed cases of M. marinum from 2004 to 2017 in Denmark. All available medical ...

  4. Complete Genome Sequence of Mycobacterium vaccae Type Strain ATCC 25954

    KAUST Repository

    Ho, Y. S.; Adroub, S. A.; Abadi, Maram; Al Alwan, B.; Alkhateeb, R.; Gao, G.; Ragab, A.; Ali, Shahjahan; van Soolingen, D.; Bitter, W.; Pain, Arnab; Abdallah, A. M.

    2012-01-01

    Mycobacterium vaccae is a rapidly growing, nontuberculous Mycobacterium species that is generally not considered a human pathogen and is of major pharmaceutical interest as an immunotherapeutic agent. We report here the annotated genome sequence of the M. vaccae type strain, ATCC 25954.

  5. Mycobacterium marinum kan være vanskelig at diagnosticere

    DEFF Research Database (Denmark)

    Lønnberg, Ann Sophie; Seersholm, Niels; Nielsen, Signe Ledou

    2012-01-01

    The diagnosis of cutaneous Mycobacterium marinum infection is often delayed for months after presentation. In this case the diagnosis and correct treatment was delayed for ten months resulting in possible irreversible damage to the patient's infected finger. The main reason for the delay is lack...... of knowledge of the mycobacterium....

  6. Complete Genome Sequence of Mycobacterium vaccae Type Strain ATCC 25954

    KAUST Repository

    Ho, Y. S.

    2012-10-26

    Mycobacterium vaccae is a rapidly growing, nontuberculous Mycobacterium species that is generally not considered a human pathogen and is of major pharmaceutical interest as an immunotherapeutic agent. We report here the annotated genome sequence of the M. vaccae type strain, ATCC 25954.

  7. An orphan gyrB in the Mycobacterium smegmatis genome

    Indian Academy of Sciences (India)

    DNA gyrase is an essential topoisomerase found in all bacteria. It is encoded by gyrB and gyrA genes. These genes are organized differently in different bacteria. Direct comparison of Mycobacterium tuberculosis and Mycobacterium smegmatis genomes reveals presence of an additional gyrB in M. smegmatis flanked by ...

  8. Risk factors for Mycobacterium tuberculosis infection among children in Greenland

    DEFF Research Database (Denmark)

    Søborg, Bolette; Andersen, Aase Bengaard; Melbye, Mads

    2011-01-01

    To examine the risk factors for Mycobacterium tuberculosis infection (MTI) among Greenlandic children for the purpose of identifying those at highest risk of infection.......To examine the risk factors for Mycobacterium tuberculosis infection (MTI) among Greenlandic children for the purpose of identifying those at highest risk of infection....

  9. Draft Genome Sequence of Mycobacterium chimaera Type Strain Fl-0169

    Science.gov (United States)

    We report the draft genome sequence of the type strain Mycobacterium chimaera Fl-0169T, a member of the Mycobacterium avium complex (MAC). M. chimaera Fl-0169T was isolated from a patient in Italy and is highly similar to strains of M. chimaera isolated in Ireland, though Fl-016...

  10. Urètrocèle post-traumatique chez l'homme: A propos de 2 cas

    African Journals Online (AJOL)

    Y. Sow

    d'épithélium et de couche musculaire lisse [2]. Il peut être secon- daire à une effraction de la paroi urétrale par un traumatisme pelvien ou périnéal [1] (c'est le cas de nos observations) ou à un traumatisme iatrogène: sondage vésical prolongé surtout chez les paraplégiques ou traumatique, urètrotomie endoscopique [3].

  11. De la ferme à la fourchette – lutte contre l'obésité chez les enfants ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    26 avr. 2016 ... ... but de combattre l'obésité chez les enfants. La démarche repose sur trois piliers, à savoir augmenter la proportion de fruits et de légumes frais dans les repas servis à l'école, faciliter l'approvisionnement en produits auprès des agriculteurs locaux et favoriser l'augmentation de la production maraîchère.

  12. Améliorer le traitement de la douleur chez les enfants en Thaïlande ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    21 avr. 2016 ... FLIKR/ROSS POLLOCK. Des lignes directrices sur la gestion de la douleur dans les hôpitaux thaïlandais aident à prévenir ou à traiter la douleur chez les enfants. Global Health Research Initiative. Les enfants sont plus susceptibles que les adultes de souffrir de l'absence de traitement ou de traitement ...

  13. A PULMONARY INFECTION CAUSED BY MYCOBACTERIUM PEREGRINUM– A CASE REPORT.

    Directory of Open Access Journals (Sweden)

    Tatina T. Todorova

    2015-12-01

    Full Text Available Mycobacterium peregrinum is a member of the group of rapidly growing Nontuberculous Mycobacteria (NTM. It can be found in high frequency in natural and laboratory environments and is considered to be uncommonrare pathogen for both immunocompetent and immunosuppressed individuals. Currently, pulmonary infections caused by Mycobacterium peregrinum are unusual and diagnosed only in limited number of cases. Here, we present a clinical case of elderly man (72 years with 1 month history of non-specific respiratory symptomatic. The patient was without underlying immunosuppressive condition or lung disease. Chest X-ray demonstrated persistent pleural effusion, opacities and cavitations in the right lobe. One of the sputum culturesgrewa rapidly growing mycobacterium and the isolated strain was found to be Mycobacterium peregrinumas identified by molecular genetic detection (PCR and DNA strip technology. To our knowledge, this is the third case in the world to report Mycobacterium peregrinumas a possible causative agent of pulmonary infection.

  14. Réponse au stress induit par le transport chez la truite arc-en-ciel (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    ROUGER Y.

    1998-07-01

    Full Text Available La réponse au stress induit par le transport a été étudiée chez des truites arc-en-ciel immatures d'un poids moyen de 200 g. D'une manière globale, les valeurs de l'hématocrite, de l'osmolarité du plasma sanguin, du Cortisol et de la testostérone sont significativement plus élevées chez les poissons transportés que chez les témoins non transportés, alors que les niveaux de gonadostimuline (GTH1 et d'hormone de croissance ne diffèrent pas suivant les lots. L'analyse du comportement en "open field" des individus de chaque lot montre que les poissons transportés s'immobilisent en moyenne après un temps significativement plus long que les témoins. L'étude des performances zootechniques de chaque lot pendant les deux mois suivant l'expérience indique que le lot transporté récupère rapidement.

  15. Mycobacterium malmesburyense sp. nov., a non-tuberculous species of the genus Mycobacterium revealed by multiple gene sequence characterization

    CSIR Research Space (South Africa)

    Gcebe, N

    2017-04-01

    Full Text Available Journal of Systematic and Evolutionary Microbiology: DOI 10.1099/ijsem.0.001678 Mycobacterium malmesburyense sp. nov., a non-tuberculous species of the genus Mycobacterium revealed by multiple gene sequence characterization Gcebe N Rutten V Gey...

  16. Immunological crossreactivity of the Mycobacterium leprae CFP-10 with its homologue in Mycobacterium tuberculosis

    NARCIS (Netherlands)

    Geluk, A.; van Meijgaarden, K. E.; Franken, K. L. M. C.; Wieles, B.; Arend, S. M.; Faber, W. R.; Naafs, B.; Ottenhoff, T. H. M.

    2004-01-01

    Mycobacterium tuberculosis culture filtrate protein-10 (CFP-10) (Rv3874) is considered a promising antigen for the immunodiagnosis of tuberculosis (TB) together with early secreted antigens of M. tuberculosis (ESAT-6). Both ESAT-6 and CFP-10 are encoded by the RD1 region that is deleted from all

  17. Bacteriological diagnosis and molecular strain typing of Mycobacterium bovis and Mycobacterium caprae.

    Science.gov (United States)

    Gormley, E; Corner, L A L; Costello, E; Rodriguez-Campos, S

    2014-10-01

    The primary isolation of a Mycobacterium sp. of the Mycobacterium tuberculosis complex from an infected animal provides a definitive diagnosis of tuberculosis. However, as Mycobacterium bovis and Mycobacterium caprae are difficult to isolate, particularly for animals in the early stages of disease, success is dependent on the optimal performance of all aspects of the bacteriological process, from the initial choice of tissue samples at post-mortem examination or clinical samples, to the type of media and conditions used to cultivate the microorganism. Each step has its own performance characteristics, which can contribute to sensitivity and specificity of the procedure, and may need to be optimized in order to achieve the gold standard diagnosis. Having isolated the slow-growing mycobacteria, species identification and fine resolution strain typing are keys to understanding the epidemiology of the disease and to devise strategies to limit transmission of infection. New technologies have emerged that can now even discriminate different isolates from the same animal. In this review we highlight the key factors that contribute to the accuracy of bacteriological diagnosis of M. bovis and M. caprae, and describe the development of advanced genotyping techniques that are increasingly used in diagnostic laboratories for the purpose of supporting detailed epidemiological investigations. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Mycobacterium sarraceniae sp. nov. and Mycobacterium helvum sp. nov., isolated from the pitcher plant Sarracenia purpurea.

    Science.gov (United States)

    Tran, Phuong M; Dahl, John L

    2016-11-01

    Several fast- to intermediate-growing, acid-fast, scotochromogenic bacteria were isolated from Sarracenia purpurea pitcher waters in Minnesota sphagnum peat bogs. Two strains (DL734T and DL739T) were among these isolates. On the basis of 16S rRNA gene sequences, the phylogenetic positions of both strains is in the genus Mycobacterium with no obvious relation to any characterized type strains of mycobacteria. Phenotypic characterization revealed that neither strain was similar to the type strains of known species of the genus Mycobacterium in the collective properties of growth, pigmentation or fatty acid composition. Strain DL734T grew at temperatures between 28 and 32 °C, was positive for 3-day arylsulfatase production, and was negative for Tween 80 hydrolysis, urease and nitrate reduction. Strain DL739T grew at temperatures between 28 and 37 °C, and was positive for Tween 80 hydrolysis, urea, nitrate reduction and 3-day arylsulfatase production. Both strains were catalase-negative while only DL739T grew with 5 % NaCl. Fatty acid methyl ester profiles were unique for each strain. DL739T showed an ability to survive at 8 °C with little to no cellular replication and is thus considered to be psychrotolerant. Therefore, strains DL734T and DL739T represent two novel species of the genus Mycobacterium with the proposed names Mycobacterium sarraceniae sp. nov. and Mycobacterium helvum sp. nov., respectively. The type strains are DL734T (=JCM 30395T=NCCB 100519T) and DL739T (=JCM 30396T=NCCB 100520T), respectively.

  19. Mesotherapy and cutaneous Mycobacterium fortuitum infection.

    Science.gov (United States)

    Difonzo, Elisa Margherita; Campanile, Grazia Lucia; Vanzi, Laura; Lotti, Lorena

    2009-06-01

    Cutaneous infections caused by Mycobacterium fortuitum usually are a complication of trauma or postsurgical wounds. A 41-year-old woman presented with numerous dusky red nodules, abscesses and sinuses on the right buttock and on the lateral surfaces of both thighs. The lesions developed at the injection sites of mesotherapy treatment. M. fortuitum was cultured from a biopsy specimen and purulent fluid drained from lesions. The lesions had cleared completely with ciprofloxacin 500 mg b.d. for 3 weeks, and then 250 mg b.d. for another 3 weeks. This case demonstrates the importance of suspecting mycobacterial etiology in patients with nodules and abscesses in the areas of mesotherapy treatment.

  20. Mycobacterium tuberculosis effectors interfering host apoptosis signaling.

    Science.gov (United States)

    Liu, Minqiang; Li, Wu; Xiang, Xiaohong; Xie, Jianping

    2015-07-01

    Tuberculosis remains a serious human public health concern. The coevolution between its pathogen Mycobacterium tuberculosis and human host complicated the way to prevent and cure TB. Apoptosis plays subtle role in this interaction. The pathogen endeavors to manipulate the apoptosis via diverse effectors targeting key signaling nodes. In this paper, we summarized the effectors pathogen used to subvert the apoptosis, such as LpqH, ESAT-6/CFP-10, LAMs. The interplay between different forms of cell deaths, such as apoptosis, autophagy, necrosis, is also discussed with a focus on the modes of action of effectors, and implications for better TB control.

  1. Mycobacterium chimaera left ventricular assist device infections.

    Science.gov (United States)

    Balsam, Leora B; Louie, Eddie; Hill, Fred; Levine, Jamie; Phillips, Michael S

    2017-06-01

    A global outbreak of invasive Mycobacterium chimaera infections after cardiac surgery has recently been linked to bioaerosols from contaminated heater-cooler units. The majority of cases have occurred after valvular surgery or aortic graft surgery and nearly half have resulted in death. To date, infections in patients with left ventricular assist devices (LVADs) have not been characterized in the literature. We report two cases of device-associated M. chimaera infection in patients with continuous-flow LVADs and describe challenges related to diagnosis and management in this population. © 2017 Wiley Periodicals, Inc.

  2. Skin granulomas due to Mycobacterium gordonae.

    Science.gov (United States)

    Gengoux, P; Portaels, F; Lachapelle, J M; Minnikin, D E; Tennstedt, D; Tamigneau, P

    1987-04-01

    A 38-year-old woman presented with small, ulcerated, red or bluish nodules on the right hand, clinically resembling mycobacterial granulomas; these appeared a few months after a bite by a rat, while the patient was collecting frogs in a pond in the Belgian Ardennes. The histopathologic picture was compatible with a diagnosis of mycobacterial infection and rare acid-fast bacilli could be found. Repeated bacteriologic investigations were performed and these led to the identification of a strain displaying characteristics of Mycobacterium gordonae. The skin condition responded well to rifampicin (300 mg/day) within 6 months.

  3. Facteurs de risque et dépistage du cancer chez les Premières Nations en Ontario

    Directory of Open Access Journals (Sweden)

    Maegan V. Mazereeuw

    2017-01-01

    Full Text Available Introduction : L'absence d'identificateurs, dans les bases de données administratives sur la santé, nous empêche de bien comprendre le fardeau du cancer chez les Premières Nations. Notre étude compare les facteurs de risque et le dépistage du cancer chez les membres des Premières Nations en Ontario (vivant dans des réserves et hors réserves et chez les Ontariens non autochtones, en s'appuyant sur deux enquêtes sur la santé. Méthodologie : Les taux normalisés selon l'âge ont été calculés en utilisant la phase 2 de l'Enquête régionale sur la santé des Premières Nations (ERS de 2008-2010 pour les Premières Nations dans des réserves et l'Enquête sur la santé dans les collectivités canadiennes (ESCC de 2007-2013 pour les membres des Premières Nations hors réserves et les Ontariens non autochtones. Des rapports de taux (RT et des tests du chi carré de Pearson (pour les différences de proportion ont été utilisés pour comparer les estimations entre les membres des Premières Nations (dans des réserves et hors réserves et les Ontariens non autochtones. Résultats : Une proportion plus élevée d'hommes, de femmes et d'adolescents des Premières Nations vivant dans des réserves fumaient (RT = 1,97, 2,78 et 7,21 respectivement et souffraient d'obésité (RT = 1,73, 2,33 et 3,29 respectivement, comparativement à leurs homologues non autochtones. Des tendances similaires ont été observées chez les membres des Premières Nations vivant hors réserves. La consommation excessive ponctuelle d'alcool fréquente était également plus répandue chez les hommes et les femmes des Premières Nations vivant dans des réserves (RT = 1,28 et 2,22, respectivement et hors réserves (RT = 1,70 et 1,45, respectivement que chez les Ontariens non autochtones. Les hommes et les femmes des Premières Nations vivant dans des réserves étaient deux fois moins susceptibles de consommer des fruits au moins deux fois par jour et des l

  4. Mycobacterium spp. in wild game in Slovenia.

    Science.gov (United States)

    Pate, Mateja; Zajc, Urška; Kušar, Darja; Žele, Diana; Vengušt, Gorazd; Pirš, Tina; Ocepek, Matjaž

    2016-02-01

    Wildlife species are an important reservoir of mycobacterial infections that may jeopardise efforts to control and eradicate bovine tuberculosis (bTB), caused by Mycobacterium bovis. Slovenia is officially free of bTB, but no data on the presence of mycobacteria in wild animals has been reported. In this study, samples of liver and lymph nodes were examined from 306 apparently healthy free-range wild animals of 13 species in Slovenia belonging to the families Cervidae, Suidae, Canidae, Mustelidae and Bovidae. Mycobacteria were isolated from 36/306 (11.8%) animals (red deer, roe deer, fallow deer, wild boar and jackal) and identified by PCR, commercial diagnostic kits and sequencing. Non-tuberculous mycobacteria identified in five species were Mycobacterium peregrinum, M. avium subsp. hominissuis, M. intracellulare, M. confluentis, M. fortuitum, M. terrae, M. avium subsp. avium, M. celatum, M. engbaekii, M. neoaurum, M. nonchromogenicum and M. vaccae. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Mycobacterium canettii Infection of Adipose Tissues.

    Science.gov (United States)

    Bouzid, Fériel; Brégeon, Fabienne; Poncin, Isabelle; Weber, Pascal; Drancourt, Michel; Canaan, Stéphane

    2017-01-01

    Adipose tissues were shown to host Mycobacterium tuberculosis which is persisting inside mature adipocytes. It remains unknown whether this holds true for Mycobacterium canettii , a rare representative of the M. tuberculosis complex responsible for lymphatic and pulmonary tuberculosis. Here, we infected primary murine white and brown pre-adipocytes and murine 3T3-L1 pre-adipocytes and mature adipocytes with M. canettii and M. tuberculosis as a positive control. Both mycobacteria were able to infect 18-22% of challenged primary murine pre-adipocytes; and to replicate within these cells during a 7-day experiment with the intracellular inoculums being significantly higher in brown than in white pre-adipocytes for M. canettii ( p = 0.02) and M. tuberculosis ( p = 0.03). Further in-vitro infection of 3T3-L1 mature adipocytes yielded 9% of infected cells by M. canettii and 17% of infected cells by M. tuberculosis ( p = 0.001). Interestingly, M. canettii replicated and accumulated intra-cytosolic lipid inclusions within mature adipocytes over a 12-day experiment; while M. tuberculosis stopped replicating at day 3 post-infection. These results indicate that brown pre-adipocytes could be one of the potential targets for M. tuberculosis complex mycobacteria; and illustrate differential outcome of M. tuberculosis complex mycobacteria into adipose tissues. While white adipose tissue is an unlikely sanctuary for M. canettii , it is still an open question whether M. canettii and M. tuberculosis could persist in brown adipose tissues.

  6. Dry-heat inactivation of "Mycobacterium canettii".

    Science.gov (United States)

    Aboubaker Osman, Djaltou; Garnotel, Eric; Drancourt, Michel

    2017-06-09

    "Mycobacterium canettii" is responsible for non-transmissible lymph node and pulmonary tuberculosis in persons exposed in the Horn of Africa. In the absence of direct human transmission, contaminated water and foodstuffs could be sources of contamination. We investigated the dry-heat inactivation of "M. canettii" alone and mixed into mock-infected foodstuffs by inoculating agar cylinders and milk with 10 4 colony-forming units of "M. canettii" CIPT140010059 and two "M. canettii" clinical strains with Mycobacterium tuberculosis H37Rv as a control. Exposed to 35 °C, M. tuberculosis H37Rv, "M canettii" CIPT140010059 and "M. canettii" 157 exhibited a survival rate of 108, 95 and 81%, which is significantly higher than that of "M. canettii" 173. However, all tested mycobacteria tolerated a 90-min exposure at 45 °C. In the foodstuff models set at 70 °C, no growing mycobacteria were visualized. This study supports the premise that "M. canettii" may survive up to 45 °C; and suggests that contaminated raw drinks and foodstuffs but not cooked ones may be sources of infection for populations.

  7. Images of mycobacterium for nuclear reactions

    International Nuclear Information System (INIS)

    Lima, C.T.S.; Crispim, V.R.; Silva, M.G.

    2007-01-01

    According to the World Health Organization (WHO) tuberculosis is responsible for 2.9 million deaths annually worldwide. The necessity for optimizing time to detect the tuberculosis bacillus (mycobacterium tuberculosis) in the sputum samples of affected individuals (TB patients) led to the development of a methodology based on the doping with boron of the bacillus, submission of the samples to thermal neutron beam and ionizing particles, generating nuclear reactions of the types: 10 B (n,α) 7 Li and 10 B(α, p) 13 C. Images of these bacilli are obtained by means of the nuclear tracks produced in the CR-39 detector for particles products of these nuclear reactions, α and p. When the CR-39 is submitted to a chemical attack the traces are developed and the images of the microorganisms registered in the detector can be observed with a conventional light microscope, characterizing them by morphology. The use of this methodology results in images of the mycobacterium tuberculosis becoming more defined and enlarged than those obtained by bacilloscopy, in which the sample is submitted to the method of coloration of Ziehl-Neelsen (ZN) and observed in light microscopy. (author)

  8. Alimentation et dépôts lipidiques chez la truite arc-en-ciel, effet de la température d’élevage

    OpenAIRE

    Corraze, Geneviève; Larroquet, Laurence; Médale, Françoise

    1999-01-01

    Cet article fait le point sur la régulation de la genèse des dépôts lipidiques par l’alimentation chez les poissons, sur la base de données bibliographiques existantes et de données personnelles obtenues chez la truite arc-en-ciel (Oncorhynchus mykiss). Chez la truite arc-en-ciel, l’importance quantitative des dépôts lipidiques corporels varie avec la teneur en lipides des aliments, mais les mécanismes de dépôts sont identiques quel que soit le régime alimentaire. Le tissu adipeux périviscéra...

  9. Radiometric assessment of the sensitivity to antituberculotics of Mycobacterium avium-intracellulare and Mycobacterium xenopi

    International Nuclear Information System (INIS)

    Kubin, M.; Lindholm-Levy, P.; Heifets, L. B.

    1994-01-01

    The macrodilution radiometric method using Middlebrook's 7H12 liquid medium enriched with 14 C-palmitic acid, where the growth activity is monitored by measuring liberated 14 CO 2 , was applied to 25 strains of the Mycobacterium avium complex and to 20 strains of Mycobacterium xenopi to determine the minimal inhibitory concentrations of the following chemotherapeutical agents: ciprofloxacine, clofazimine, rifampin, cycloserine, kanamycin, etionamide, ethambutol, and amikacin. In the case of the M. avium complex, slightly or completely resistant strains were found for the majority of drugs. The sensitive strain proportion was highest with clofazimine and amikacin. The M. xenopis strains exhibited generally lower minimal inhibitory concentrations than the avian mycobacteria for all drugs except for cycloserine and ethambutol. The radiometric method using the BACTEC system was found suitable for the determination of the sensitivity of mycobacteria to chemotherapeutic agents: the results are obtained rapidly, within 8 days following inoculation, and the minimal inhibitory concentrations can be evaluated quantitatively. 1 tab., 8 refs

  10. Distinct Spatiotemporal Dynamics of Peptidoglycan Synthesis between Mycobacterium smegmatis and Mycobacterium tuberculosis

    Directory of Open Access Journals (Sweden)

    Helene Botella

    2017-09-01

    Full Text Available Peptidoglycan (PG, a polymer cross-linked by d-amino acid-containing peptides, is an essential component of the bacterial cell wall. We found that a fluorescent d-alanine analog (FDAA incorporates chiefly at one of the two poles in Mycobacterium smegmatis but that polar dominance varies as a function of the cell cycle in Mycobacterium tuberculosis: immediately after cytokinesis, FDAAs are incorporated chiefly at one of the two poles, but just before cytokinesis, FDAAs are incorporated comparably at both. These observations suggest that mycobacterial PG-synthesizing enzymes are localized in functional compartments at the poles and septum and that the capacity for PG synthesis matures at the new pole in M. tuberculosis. Deeper knowledge of the biology of mycobacterial PG synthesis may help in discovering drugs that disable previously unappreciated steps in the process.

  11. A Case of False-Positive Mycobacterium tuberculosis Caused by Mycobacterium celatum

    Directory of Open Access Journals (Sweden)

    Edward Gildeh

    2016-01-01

    Full Text Available Mycobacterium celatum is a nontuberculous mycobacterium shown to cause symptoms similar to pulmonary M. tuberculosis. Certain strains have been shown to cross-react with the probes used to detect M. tuberculosis, making this a diagnostic challenge. We present a 56-year-old gentleman who developed signs and symptoms of lung infection with computed tomography scan of the chest showing right lung apex cavitation. Serial sputum samples were positive for acid-fast bacilli and nucleic acid amplification testing identified M. tuberculosis ribosomal RNA, resulting in treatment initiation. Further testing with high performance liquid chromatography showed a pattern consistent with M. celatum. This case illustrates the potential for M. celatum to mimic M. tuberculosis in both its clinical history and laboratory testing due to the identical oligonucleotide sequence contained in both. An increasing number of case reports suggest that early reliable differentiation could reduce unnecessary treatment and public health intervention associated with misdiagnosed tuberculosis.

  12. [Cutaneous infection by Mycobacterium fortuitum]  Infeccion cutanea por Mycobacterium fortuitum

    Directory of Open Access Journals (Sweden)

    Verónica Rotela

    2017-10-01

    Full Text Available Mycobacteria are aerobic, non-spore forming, gram positive, acid-fast bacilli, which affect skin, subcutaneous tissue, and other organs and systems. Mycobacterium fortuitum produces cellulitis, abscesses, papules-pustules, nodules and ulcers with serosanguinolent, purulent material, and subcutaneous necrosis. A 61-year-old woman, presents a case of two months of evolution that begins with reddish grain from an insect sting. After immersion in the Mexican Sea, it worsens, increases in quantity, is blistered and has brownish secretion; Physical examination shows erythematous plaque, with punctate orifices with hematic and meliceric crusts; Pustules and satellite papules, on the anterior aspect of the right leg. Histopathology: Suppurative dermal granulomas, centered by acute leukocyte infiltrate, with liquefactive tissue necrosis, surrounded by chronic inflammation with macrophages, plasma cells, lymphocytes, multinucleated giant cells. The first skin culture returns negative; in the second skin culture, fast-growing, non-pigmented atypical mycobacteria. Molecular detection is performed by Polymerase Chain Reaction: Mycobacterium fortuitum. Treatment with Ciprofloxacin 500 mg every 12 hours, with resolution of the table to the eighth month. A case of cutaneous infection by Mycobacterium fortuitum, related to the immersion in the sea and corals, whose diagnostic process has been difficult and was achieved by techniques of advanced molecular biology.

  13. Chronic breast abscess due to Mycobacterium fortuitum: a case report

    Directory of Open Access Journals (Sweden)

    MacNeill Fiona A

    2011-05-01

    Full Text Available Abstract Introduction Mycobacterium fortuitum is a rapidly growing group of nontuberculous mycobacteria more common in patients with genetic or acquired causes of immune deficiency. There have been few published reports of Mycobacterium fortuitum associated with breast infections mainly associated with breast implant and reconstructive surgery. Case presentation We report a case of a 51-year-old Caucasian woman who presented to our one-stop breast clinic with a two-week history of left breast swelling and tenderness. Following triple assessment and subsequent incision and drainage of a breast abscess, the patient was diagnosed with Mycobacterium fortuitum and treated with antibiotic therapy and surgical debridement. Conclusion This is a rare case of a spontaneous breast abscess secondary to Mycobacterium fortuitum infection. Recommended treatment is long-term antibacterial therapy and surgical debridement for extensive infection or when implants are involved.

  14. Buoyant density of Mycobacterium tuberculosis: implications for sputum processing

    NARCIS (Netherlands)

    den Hertog, A. L.; Klatser, P. R.; Anthony, R. M.

    2009-01-01

    A tuberculosis (TB) research laboratory in the Netherlands. The concentration of Mycobacterium tuberculosis cells from sputum is almost universally performed by centrifugation after chemical liquefaction. These methods are thus dependent on the effective sedimentation of mycobacterial cells, and the

  15. Variable host-pathogen compatibility in Mycobacterium tuberculosis.

    NARCIS (Netherlands)

    Gagneux, Sebastien; DeRiemer, Kathryn; Van, Tran; Kato-Maeda, Midori; Jong, Bouke C de; Narayanan, Sujatha; Nicol, Mark; Niemann, Stefan; Kremer, Kristin; Gutierrez, M Cristina; Hilty, Markus; Hopewell, Philip C; Small, Peter M

    2006-01-01

    Mycobacterium tuberculosis remains a major cause of morbidity and mortality worldwide. Studies have reported human pathogens to have geographically structured population genetics, some of which have been linked to ancient human migrations. However, no study has addressed the potential evolutionary

  16. EVIDENCE FOR THE MACROPHAGE INDUCING GENE IN MYCOBACTERIUM INTRACELLULARE

    Science.gov (United States)

    Background: The Mycobacterium avium Complex (MAC) includes the species M. avium (MA), M. intracellulare (MI), and possibly others. Organisms belonging to the MAC are phylogenetically closely related, opportunistic pathogens. The macrophage inducing gene (mig) is the only well-des...

  17. A robust SNP barcode for typing Mycobacterium tuberculosis complex strains

    KAUST Repository

    Coll, Francesc; McNerney, Ruth; Guerra-Assunç ã o, José Afonso; Glynn, Judith R.; Perdigã o, Joã o; Viveiros, Miguel; Portugal, Isabel; Pain, Arnab; Martin, Nigel; Clark, Taane G.

    2014-01-01

    Strain-specific genomic diversity in the Mycobacterium tuberculosis complex (MTBC) is an important factor in pathogenesis that may affect virulence, transmissibility, host response and emergence of drug resistance. Several systems have been proposed

  18. Drug susceptibility testing of Mycobacterium tuberculosis to fluoroquinolones

    DEFF Research Database (Denmark)

    Johansen, I S; Larsen, A R; Sandven, P

    2003-01-01

    In the first attempt to establish a quality assurance programme for susceptibility testing of Mycobacterium tuberculosis to fluoroquinolones, 20 strains with different fluoroquinolone susceptibility patterns were distributed by the Supranational Reference Laboratory in Stockholm to the other...

  19. Bloodstream Infections with Mycobacterium tuberculosis among HIV patients

    Centers for Disease Control (CDC) Podcasts

    This podcast looks at bloodstream infections with Mycobacterium tuberculosis and other pathogens among outpatients infected with HIV in Southeast Asia. CDC health scientist Kimberly McCarthy discusses the study and why bloodstream infections occur in HIV-infected populations.

  20. Complete Genome Sequence of Mycobacterium xenopi Type Strain RIVM700367

    KAUST Repository

    Abdallah, A. M.; Rashid, M.; Adroub, S. A.; Elabdalaoui, H.; Ali, Shahjahan; van Soolingen, D.; Bitter, W.; Pain, Arnab

    2012-01-01

    Mycobacterium xenopi is a slow-growing, thermophilic, water-related Mycobacterium species. Like other nontuberculous mycobacteria, M. xenopi more commonly infects humans with altered immune function, such as chronic obstructive pulmonary disease patients. It is considered clinically relevant in a significant proportion of the patients from whom it is isolated. We report here the whole genome sequence of M. xenopi type strain RIVM700367.

  1. Complete Genome Sequence of Mycobacterium xenopi Type Strain RIVM700367

    KAUST Repository

    Abdallah, A. M.

    2012-05-24

    Mycobacterium xenopi is a slow-growing, thermophilic, water-related Mycobacterium species. Like other nontuberculous mycobacteria, M. xenopi more commonly infects humans with altered immune function, such as chronic obstructive pulmonary disease patients. It is considered clinically relevant in a significant proportion of the patients from whom it is isolated. We report here the whole genome sequence of M. xenopi type strain RIVM700367.

  2. Mycobacterium chelonae empyema with bronchopleural fistula in an immunocompetent patient

    International Nuclear Information System (INIS)

    Wali, Siraj

    2009-01-01

    Mycobacterium Calhoun is one of the rapidly growing mycobacteria that rarely cause lung disease. M chelonae more commonly causes skin and soft tissue infections primarily in immunosuppressed individuals. Thoracic empyema caused by rapidly growing mycobacteria and complicated with bronchopleural fistula is rarely reported, especially in immunocompetent patients. In this article we report the first immunocompetent Arabian patient presented with M chelonae- related empyema with bronchopleural fistula which mimics, clinically and radiologically, empyema caused by Mycobacterium tuberculosis. (author)

  3. Mycobacterium Diversity and Pyrene Mineralization in Petroleum-Contaminated Soils

    OpenAIRE

    Cheung, Pui-Yi; Kinkle, Brian K.

    2001-01-01

    Degradative strains of fast-growing Mycobacterium spp. are commonly isolated from polycyclic aromatic hydrocarbon (PAH)-contaminated soils. Little is known, however, about the ecology and diversity of indigenous populations of these fast-growing mycobacteria in contaminated environments. In the present study 16S rRNA genes were PCR amplified using Mycobacterium-specific primers and separated by temperature gradient gel electrophoresis (TGGE), and prominent bands were sequenced to compare the ...

  4. Mycobacterium arupense, Mycobacterium heraklionense, and a Newly Proposed Species, “Mycobacterium virginiense” sp. nov., but Not Mycobacterium nonchromogenicum, as Species of the Mycobacterium terrae Complex Causing Tenosynovitis and Osteomyelitis

    Science.gov (United States)

    Vasireddy, Sruthi; Brown-Elliott, Barbara A.; Wengenack, Nancy L.; Eke, Uzoamaka A.; Benwill, Jeana L.; Turenne, Christine; Wallace, Richard J.

    2016-01-01

    Mycobacterium terrae complex has been recognized as a cause of tenosynovitis, with M. terrae and Mycobacterium nonchromogenicum reported as the primary etiologic pathogens. The molecular taxonomy of the M. terrae complex causing tenosynovitis has not been established despite approximately 50 previously reported cases. We evaluated 26 isolates of the M. terrae complex associated with tenosynovitis or osteomyelitis recovered between 1984 and 2014 from 13 states, including 5 isolates reported in 1991 as M. nonchromogenicum by nonmolecular methods. The isolates belonged to three validated species, one new proposed species, and two novel related strains. The majority of isolates (20/26, or 77%) belonged to two recently described species: Mycobacterium arupense (10 isolates, or 38%) and Mycobacterium heraklionense (10 isolates, or 38%). Three isolates (12%) had 100% sequence identity to each other by 16S rRNA and 99.3 to 100% identity by rpoB gene region V sequencing and represent a previously undescribed species within the M. terrae complex. There were no isolates of M. terrae or M. nonchromogenicum, including among the five isolates reported in 1991. The 26 isolates were susceptible to clarithromycin (100%), rifabutin (100%), ethambutol (92%), and sulfamethoxazole or trimethoprim-sulfamethoxazole (70%). The current study suggests that M. arupense, M. heraklionense, and a newly proposed species (“M. virginiense” sp. nov.; proposed type strain MO-233 [DSM 100883, CIP 110918]) within the M. terrae complex are the major causes of tenosynovitis and osteomyelitis in the United States, with little change over 20 years. Species identification within this complex requires sequencing methods. PMID:26962085

  5. Échecs thérapeutiques chez les enfants infectés par le VIH en suivi ...

    African Journals Online (AJOL)

    Introduction: L'objectif de cette étude était de déterminer les facteurs associés aux échecs thérapeutiques chez les enfants infectés par le VIH à l'Hôpital Laquintinie de Douala. Méthodes: Une étude transversale rétrospective a été menée sur une période de 5 mois en 2010, recrutant 222 enfants âgés de 1 à 18 ans et sous ...

  6. S'attaquer au chômage chez les jeunes en Éthiopie grâce au ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le chômage chez les jeunes constitue un problème de taille aussi bien pour les pays industrialisés que pour les pays en développement. L'Éthiopie ne fait pas exception. Quels sont les politiques et les programmes qui favorisent l'emploi des jeunes et quel rôle le secteur privé peut-il jouer à cet égard ? Le présent projet ...

  7. La grossesse chez l'adolescente à l'hôpital de Tsévié (Togo ...

    African Journals Online (AJOL)

    Objectif : Décrire le profil des grossesses chez l'adolescente à l'hôpital de Tsévié (Togo). Matériel et méthode : Il s'agissait d'une étude descriptive analytique portant sur les dossiers des parturientes âgées de 10 à 19 ans reçues à l'hôpital de Tsévié entre janvier 2011 et juin 2012. Résultats : Au cours de cette période, 180 ...

  8. Les effets potentiels du taping chez une population adulte souffrant d'un conflit sous-acromial

    OpenAIRE

    Roch, Sylvie; Thétaz, Alain; Balthazard, Pierre

    2012-01-01

    Introduction : Le conflit sous-acromial est une pathologie fréquente qui touche une grande partie de la population. Quelques revues de la littérature recommandent une prise en charge spécifique, mais peu d’études proposent le taping comme adjuvant aux traitements préconisés. Ainsi ce travail de bachelor a pour objectif de déterminer les effets potentiels du taping chez une population adulte souffrant de conflit sous-acromial. Méthodologie : Notre recherche d’études s’est effectuée de janvier ...

  9. Epidémiologie de l'infection urinaire chez l'enfant au CHU-Campus ...

    African Journals Online (AJOL)

    Titre : Epidémiologie de l'infection urinaire chez l'enfant au CHU-Campus de Lomé. Objectif : Evaluer la prévalence et étudier l'épidémiologie des infections urinaires. Méthodologie : Il s'agit d'une étude prospective qui s'est déroulée du 1er janvier au 31décembre 2009, dans le service de pédiatrie du CHU-Campus de ...

  10. Mycobacterium Tuberculosis Pyomyositis in an Infant

    Science.gov (United States)

    Malik, ZA; Shehab, M

    2013-01-01

    Mycobacterium tuberculosis is endemic to many parts of the world. It may have variable clinical presentations, especially in the pediatric age group. Presented here is the case of a 9-month old infant who was referred for infectious disease opinion when his thigh induration failed to improve after surgical drainage and a course of oral antibiotic therapy. Mycobacterial PCR on the operative sample fluid was found to be positive; and mycobacterial culture grew M. tuberculosis. He received 9 months of treatment with anti-TB medications, with excellent results and complete recovery. This is the first report of TB pyomyositis in an infant; and highlights the need to have a high index of suspicion for unusual organisms when conventional therapy fails to demonstrate expected results. PMID:23919207

  11. Virulence factors of the Mycobacterium tuberculosis complex

    Science.gov (United States)

    Forrellad, Marina A.; Klepp, Laura I.; Gioffré, Andrea; Sabio y García, Julia; Morbidoni, Hector R.; Santangelo, María de la Paz; Cataldi, Angel A.; Bigi, Fabiana

    2013-01-01

    The Mycobacterium tuberculosis complex (MTBC) consists of closely related species that cause tuberculosis in both humans and animals. This illness, still today, remains to be one of the leading causes of morbidity and mortality throughout the world. The mycobacteria enter the host by air, and, once in the lungs, are phagocytated by macrophages. This may lead to the rapid elimination of the bacillus or to the triggering of an active tuberculosis infection. A large number of different virulence factors have evolved in MTBC members as a response to the host immune reaction. The aim of this review is to describe the bacterial genes/proteins that are essential for the virulence of MTBC species, and that have been demonstrated in an in vivo model of infection. Knowledge of MTBC virulence factors is essential for the development of new vaccines and drugs to help manage the disease toward an increasingly more tuberculosis-free world. PMID:23076359

  12. MYCOBACTERIUM AVIUM SUSP. PARATUBERCULOSIS IN DAIRY PRODUCTION

    Directory of Open Access Journals (Sweden)

    G. Marchetti

    2012-08-01

    Full Text Available Mycobacterium avium subsp. paratuberculosis (MAP is the etiologic agent of paratuberculosis. The disease affects cows and other ruminants and causes high economic losses, mainly for dairy production. MAP may also have a role in the development of Crohn’s disease in humans. Infected animals shed viable MAP with milk and faeces and humans may assume MAP via the consumption of contaminated milk and dairy products. Current methods of milk pasteurization are not sufficient to kill all MAP cells present in milk and MAP has been found in raw or pasteurized milk and isolated from cheese. The aim of this paper is to review the current knowledge about MAP in dairy production. We analyzed studies on milk contamination, effect of pasteurization and methods for identification of MAP that can be applied to dairy products.

  13. Advances in Proteomics of Mycobacterium leprae.

    Science.gov (United States)

    Parkash, O; Singh, B P

    2012-04-01

    Although Mycobacterium leprae was the first bacterial pathogen identified causing human disease, it remains one of the few that is non-cultivable. Understanding the biology of M. leprae is one of the primary challenges in current leprosy research. Genomics has been extremely valuable, nonetheless, functional proteins are ultimately responsible for controlling most aspects of cellular functions, which in turn could facilitate parasitizing the host. Furthermore, bacterial proteins provide targets for most of the vaccines and immunodiagnostic tools. Better understanding of the proteomics of M. leprae could also help in developing new drugs against M. leprae. During the past nearly 15 years, there have been several developments towards the identification of M. leprae proteins employing contemporary proteomics tools. In this review, we discuss the knowledge gained on the biology and pathogenesis of M. leprae from current proteomic studies. © 2012 The Authors. Scandinavian Journal of Immunology © 2012 Blackwell Publishing Ltd.

  14. Mycobacterium leprae: genes, pseudogenes and genetic diversity

    Science.gov (United States)

    Singh, Pushpendra; Cole, Stewart T

    2011-01-01

    Leprosy, which has afflicted human populations for millenia, results from infection with Mycobacterium leprae, an unculturable pathogen with an exceptionally long generation time. Considerable insight into the biology and drug resistance of the leprosy bacillus has been obtained from genomics. M. leprae has undergone reductive evolution and pseudogenes now occupy half of its genome. Comparative genomics of four different strains revealed remarkable conservation of the genome (99.995% identity) yet uncovered 215 polymorphic sites, mainly single nucleotide polymorphisms, and a handful of new pseudogenes. Mapping these polymorphisms in a large panel of strains defined 16 single nucleotide polymorphism-subtypes that showed strong geographical associations and helped retrace the evolution of M. leprae. PMID:21162636

  15. Consequences of genomic diversity in Mycobacterium tuberculosis

    Science.gov (United States)

    Coscolla, Mireia; Gagneux, Sebastien

    2014-01-01

    The causative agent of human tuberculosis, Mycobacterium tuberculosis complex (MTBC), comprises seven phylogenetically distinct lineages associated with different geographical regions. Here we review the latest findings on the nature and amount of genomic diversity within and between MTBC lineages. We then review recent evidence for the effect of this genomic diversity on mycobacterial phenotypes measured experimentally and in clinical settings. We conclude that overall, the most geographically widespread Lineage 2 (includes Beijing) and Lineage 4 (also known as Euro-American) are more virulent than other lineages that are more geographically restricted. This increased virulence is associated with delayed or reduced pro-inflammatory host immune responses, greater severity of disease, and enhanced transmission. Future work should focus on the interaction between MTBC and human genetic diversity, as well as on the environmental factors that modulate these interactions. PMID:25453224

  16. Associations between Mycobacterium tuberculosis Strains and Phenotypes

    Science.gov (United States)

    Brown, Timothy; Nikolayevskyy, Vladyslav; Velji, Preya

    2010-01-01

    To inform development of tuberculosis (TB) control strategies, we characterized a total of 2,261 Mycobacterium tuberculosis complex isolates by using multiple phenotypic and molecular markers, including polymorphisms in repetitive sequences (spoligotyping and variable-number tandem repeats [VNTRs]) and large sequence and single-nucleotide polymorphisms. The Beijing family was strongly associated with multidrug resistance (p = 0.0001), and VNTR allelic variants showed strong associations with spoligotyping families: >5 copies at exact tandem repeat (ETR) A, >2 at mycobacterial interspersed repetitive unit 24, and >3 at ETR-B associated with the East African–Indian and M. bovis strains. All M. tuberculosis isolates were differentiated into 4 major lineages, and a maximum parsimony tree was constructed suggesting a more complex phylogeny for M. africanum. These findings can be used as a model of pathogen global diversity. PMID:20113558

  17. Mycobacterium abscessus Complex Infections in Humans.

    Science.gov (United States)

    Lee, Meng-Rui; Sheng, Wang-Huei; Hung, Chien-Ching; Yu, Chong-Jen; Lee, Li-Na; Hsueh, Po-Ren

    2015-09-01

    Mycobacterium abscessus complex comprises a group of rapidly growing, multidrug-resistant, nontuberculous mycobacteria that are responsible for a wide spectrum of skin and soft tissue diseases, central nervous system infections, bacteremia, and ocular and other infections. M. abscessus complex is differentiated into 3 subspecies: M. abscessus subsp. abscessus, M. abscessus subsp. massiliense, and M. abscessus subsp. bolletii. The 2 major subspecies, M. abscessus subsp. abscessus and M. abscessus subsp. massiliense, have different erm(41) gene patterns. This gene provides intrinsic resistance to macrolides, so the different patterns lead to different treatment outcomes. M. abscessus complex outbreaks associated with cosmetic procedures and nosocomial transmissions are not uncommon. Clarithromycin, amikacin, and cefoxitin are the current antimicrobial drugs of choice for treatment. However, new treatment regimens are urgently needed, as are rapid and inexpensive identification methods and measures to contain nosocomial transmission and outbreaks.

  18. Autoradiographic and metabolic studies of Mycobacterium leprae

    International Nuclear Information System (INIS)

    Khanolkar, S.R.; Ambrose, E.J.; Chulawala, R.G.; Bapat, C.V.

    1978-01-01

    Highly purified suspensions of Mycobacterium leprae show a progressive increase in incorporation of [ 3 H]thymidine and [ 3 H]DOPA in short-term cultures as shown by scintillation counting. The intact bacilli are known to have a high permeability barrier. The experiments described suggest that [ 3 H]DOPA becomes trapped within this barrier and oxidized inside the bacilli. Tests by pre-treatment with diethyl dithiocarbamate (DDC inhibitor of DOPA), cold DOPA or hyaluronidase distinguish the uptake of [ 3 H]DOPA by bacilli from the effects of connective tissue contamination. Similar increases in labelling of bacilli by scintillation counting of cultures, have been observed by autoradiography of the organisms. The scintillation method shows promise for rapidly identifying drug resistance in lepromatous patients relapsing while on treatment with dapsone (DDS) rifampicin, clofazimine or other anti-leprosy drugs. (author)

  19. Phenotypic and genomic comparison of Mycobacterium aurum and surrogate model species to Mycobacterium tuberculosis: implications for drug discovery.

    Science.gov (United States)

    Namouchi, Amine; Cimino, Mena; Favre-Rochex, Sandrine; Charles, Patricia; Gicquel, Brigitte

    2017-07-13

    Tuberculosis (TB) is caused by Mycobacterium tuberculosis and represents one of the major challenges facing drug discovery initiatives worldwide. The considerable rise in bacterial drug resistance in recent years has led to the need of new drugs and drug regimens. Model systems are regularly used to speed-up the drug discovery process and circumvent biosafety issues associated with manipulating M. tuberculosis. These include the use of strains such as Mycobacterium smegmatis and Mycobacterium marinum that can be handled in biosafety level 2 facilities, making high-throughput screening feasible. However, each of these model species have their own limitations. We report and describe the first complete genome sequence of Mycobacterium aurum ATCC23366, an environmental mycobacterium that can also grow in the gut of humans and animals as part of the microbiota. This species shows a comparable resistance profile to that of M. tuberculosis for several anti-TB drugs. The aims of this study were to (i) determine the drug resistance profile of a recently proposed model species, Mycobacterium aurum, strain ATCC23366, for anti-TB drug discovery as well as Mycobacterium smegmatis and Mycobacterium marinum (ii) sequence and annotate the complete genome sequence of this species obtained using Pacific Bioscience technology (iii) perform comparative genomics analyses of the various surrogate strains with M. tuberculosis (iv) discuss how the choice of the surrogate model used for drug screening can affect the drug discovery process. We describe the complete genome sequence of M. aurum, a surrogate model for anti-tuberculosis drug discovery. Most of the genes already reported to be associated with drug resistance are shared between all the surrogate strains and M. tuberculosis. We consider that M. aurum might be used in high-throughput screening for tuberculosis drug discovery. We also highly recommend the use of different model species during the drug discovery screening process.

  20. Comparison of the UDP-N-Acetylmuramate:l-Alanine Ligase Enzymes from Mycobacterium tuberculosis and Mycobacterium leprae

    Science.gov (United States)

    Mahapatra, Sebabrata; Crick, Dean C.; Brennan, Patrick J.

    2000-01-01

    In the peptidoglycan of Mycobacterium leprae, l-alanine of the side chain is replaced by glycine. When expressed in Escherichia coli, MurC (UDP-N-acetyl-muramate:l-alanine ligase) of M. leprae showed Km and Vmax for l-alanine and glycine similar to those of Mycobacterium tuberculosis MurC, suggesting that another explanation should be sought for the presence of glycine. PMID:11073931

  1. Comparison of the UDP-N-Acetylmuramate:l-Alanine Ligase Enzymes from Mycobacterium tuberculosis and Mycobacterium leprae

    OpenAIRE

    Mahapatra, Sebabrata; Crick, Dean C.; Brennan, Patrick J.

    2000-01-01

    In the peptidoglycan of Mycobacterium leprae, l-alanine of the side chain is replaced by glycine. When expressed in Escherichia coli, MurC (UDP-N-acetyl-muramate:l-alanine ligase) of M. leprae showed Km and Vmax for l-alanine and glycine similar to those of Mycobacterium tuberculosis MurC, suggesting that another explanation should be sought for the presence of glycine.

  2. Fatty Acyl Chains of Mycobacterium marinum Lipooligosaccharides

    Science.gov (United States)

    Rombouts, Yoann; Alibaud, Laeticia; Carrère-Kremer, Séverine; Maes, Emmanuel; Tokarski, Caroline; Elass, Elisabeth; Kremer, Laurent; Guérardel, Yann

    2011-01-01

    We have recently established the fine structure of the glycan backbone of lipooligosaccharides (LOS-I to LOS-IV) isolated from Mycobacterium marinum, a close relative of Mycobacterium tuberculosis. These studies culminated with the description of an unusual terminal N-acylated monosaccharide that confers important biological functions to LOS-IV, such as macrophage activation, that may be relevant to granuloma formation. It was, however, also suggested that the lipid moiety was required for LOSs to exert their immunomodulatory activity. Herein, using highly purified LOSs from M. marinum, we have determined through a combination of mass spectrometric and NMR techniques, the structure and localization of the fatty acids composing the lipid moiety. The occurrence of two distinct polymethyl-branched fatty acids presenting specific localizations is consistent with the presence of two highly related polyketide synthases (Pks5 and Pks5.1) in M. marinum and presumably involved in the synthesis of these fatty acyl chains. In addition, a bioinformatic search permitted us to identify a set of enzymes potentially involved in the biosynthesis or transfer of these lipids to the LOS trehalose unit. These include MMAR_2343, a member of the Pap (polyketide-associated protein) family, that acylates trehalose-based glycolipids in M. marinum. The participation of MMAR_2343 to LOS assembly was demonstrated using a M. marinum mutant carrying a transposon insertion in the MMAR_2343 gene. Disruption of MMAR_2343 resulted in a severe LOS breakdown, indicating that MMAR_2343, hereafter designated PapA4, fulfills the requirements for LOS acylation and assembly. PMID:21803773

  3. Multinucleated giant cell cytokine expression in pulmonary granulomas of cattle experimentally infected with Mycobacterium bovis

    Science.gov (United States)

    Pathogenic mycobacteria of the Mycobacterium tuberculosis complex such as Mycobacterium bovis, induce a characteristic lesion known as a granulomas. Granulomas represent a specific host response to chronic antigenic stimuli, such as foreign bodies, certain bacterial components, or persistent pathoge...

  4. Pott's disease: a case of Mycobacterium xenopi infection of the spine.

    Science.gov (United States)

    Alfreijat, Majd; Ononiwu, Chiagozie; Sexton, Carlton

    2012-01-01

    Pott's disease is an infection of the spine with Mycobacterium tuberculosis that causes destruction of the spine elements resulting in progressive kyphosis. We are describing a rare case of Pott's disease where Mycobacterium xenopi was the inculpated organism.

  5. La poétique de la contradiction chez Nelly Arcan

    Directory of Open Access Journals (Sweden)

    Laurence Gauvreau

    2015-12-01

    Full Text Available L’autofiction chez Nelly Arcan, en plus de mettre en scène l’union atypique, bien que déjà vue, de l’écriture et de la prostitution, donne l’impression d’être tout entier un rassemblement de pensées opposées, incompatibles, en désordre. S’opposer à soi-même peut montrer l’existence d’un esprit critique, en plus de la capacité à pousser celui-ci au-delà du simple débat entre amis. La critique négative et la négativité de la critique pénètrent profondément le processus d’écriture dans les autofictions d’Arcan, Putain et Folle, et cette dernière possède définitivement un esprit critique. Par contre, celui-ci ne semble pas la source des oppositions qui caractérisent sa plume. La poétique de l’auteure semble en effet être fondée sur l’utilisation constante d’une série de contradictions. C’est dans la tension de l’exploration de ces contradictions, de la force de cette dialectique négative, qu’Arcan tente de faire éclater le sens des préjugés, de ce qui a été jugé d’avance sans aucun esprit critique, afin d’atteindre une conception et une compréhension qui seraient plus authentiques.

  6. La prise en charge des morsures de chien chez les enfants

    Science.gov (United States)

    Sabhaney, Vikram; Goldman, Ran D.

    2012-01-01

    Résumé Question Une fillette de 4 ans jouait avec le chien de ses voisins. Le chien s’est excité et a mordu la jeune fille à l’avant-bras, y laissant une plaie punctiforme. À cause cette blessure, elle s’est présentée à mon bureau. Devrais-je la traiter avec des antibiotiques? Quel antibiotique faut-il utiliser et pendant combien de temps? Réponse L’administration d’antibiotiques prophylactiques est indiquée lorsqu’on a procédé à une suture primitive de la morsure, que la plaie est de gravité modérée à sévère, qu’elle est punctiforme (particulièrement s’il y a eu pénétration de l’os, de la gaine tendineuse ou de l’articulation), pour les morsures au visage, aux mains, aux pieds ou aux parties génitales ou lorsque les victimes sont immunodéprimées ou souffrent d’asplénisme. L’antibiotique de première intention est l’amoxicilline-clavulanate. La prophylaxie appropriée antitétanique et contre la rage devrait faire partie des soins chez un patient qui a été mordu par un chien, tout comme le débridement local et le nettoyage complet de la plaie.

  7. Les interactions entre la reproduction et la biologie des populations chez les Monogènes Gyrodactylidae : revue

    Directory of Open Access Journals (Sweden)

    HARRIS P. D.

    1993-01-01

    Full Text Available Les Gyrodactylidae sont des Monogènes vivipares, les embryons se développent de manière emboitée dans l'utérus maternel. Les premier et deuxième individus fils se développent sans auto, ni fécondation croisée ; seuls les troisième et suivants peuvent se développer sexuellement. L'importance relative de la reproduction sexuée, dépend de la structure d'âge de la population et de la mortalité. Chez Macrogyrodactylus polypteri, le développement postnatal de l'appareil génital femelle facilite la fécondation croisée chez tous les individus suivant la seconde naissance. La reproduction asexuée maximise la croissance de la population mais la sexualité intervient régulièrement. Gyrdicotylus gallieni, qui parasite la bouche de Xenopus laevis, présente une croissance exceptionnellement lente de la population et les populations parasites sont surtout composées d'individus âgés et sexuellement matures. Isancistrum subulatae, parasite du Calmar Alloteuthis subulata, forme d'importantes populations, mais leur croissance est probablement lente, et la structure d'âge suggère que la sexualité est courante. Chez Gyrodactylus, plusieurs stratégies existent. Gyrodactylus turnbulli, chez les Guppis, a une courte durée de vie et manifeste une mortalité spécifique croissant exponentiellement avec l'âge, de telle sorte que moins d'un pour cent survivent assez longtemps pour donner une troisième naissance. La reproduction est principalement asexuée mais le sexe intervient dans les populations de très fortes densités. Dans la nature la reproduction asexuée prédomine sans doute et cette espèce peut être considérée comme cycliquement parthénogénétique. Chez le saumon, Gyrodactylus salaris, présente des mortalités faibles et 10-15% des survivants se reproduisent sexuellement. Des individus fécondés sont trouvés même dans les faibles infestations et la sexualité est habituelle dans la biologie de cette espèce. Chez

  8. Après le spectacle : les impacts psychosociaux de consommation de pornographie homosexuelle masculine chez les hommes gais

    Directory of Open Access Journals (Sweden)

    SIMON CORNEAU

    2010-01-01

    Full Text Available Cette recherche qualitative exploratoire vise à mettre à jour les impacts psychosociaux possibles de consommation de pornographie homosexuelle masculine à travers les discours de 20 usagers gais de Toronto (Canada. La consommation de pornographie semble plus acceptée et normalisée chez les hommes gais que chez les hommes hétérosexuels. Une telle consommation peut avoir une incidence sur certains aspects de la santé sexuelle et de la santé mentale. L'analyse thématique du corpus de nos données nous révèle que les impacts peuvent se faire sentir au niveau de l'apprentissage, de l'édification de la fantasmatique, de la validation de la sexualité entre hommes, de l'ingérence dans la vie sexuelle et enfin, sur l'habituation et sur l'image de soi/image corporelle. À l'aide de l’analyse critique de discours, nous avons pu documenter les discours sociaux plus larges en jeu dans les récits des usagers et voir de quelle façon ils se positionnent à l'intérieur de ces mêmes discours.

  9. MODULATION DE L’INSULINO-SECRETION PAR LES CYTOKINES CHEZ LE RAT DES SABLES ET LE RAT WISTAR: ETUDE INTERSPECIFIQUE

    Directory of Open Access Journals (Sweden)

    A HADDAR

    2001-12-01

    Dans cette étude, nous avons comparé l’activité insulinosécrétoire des îlots de Langerhans isolés du rat Wistar et du rat des sables, afin de déterminer les variation interspécifiques. Nos résultats préliminaires indiquent que l'effet le plus probant est observé en présence de l’IL-1b. En effet, cette cytokine stimule la sécrétion d’insuline de manière dose-dépendante également chez le rat des sables; toutefois, l'amplitude de la réponse est plus prononcée chez le rongeur désertique, avec une augmentation du taux de l’insuline libérée de l’ordre de 147%, en présence d’une concentration de 20 UI/ml de l’IL-1b, comparée à la sécrétion basale. Quant à l’IL-2, nous n’avons enregistré aucune modification dans l’activité insulinosécrétoire des 2 espèces.

  10. Brûlure chez l’épileptique: brûlure pas comme les autres

    Science.gov (United States)

    Boukind, S.; Elatiqi, O.K.; Dlimi, M.; Elamrani, D.; Benchamkha, Y.; Ettalbi, S.

    2015-01-01

    Summary L’association brûlure et épilepsie est une constatation fréquente au Maroc. Ces brûlures, souvent itératives, touchent le plus souvent des femmes jeunes de milieu rural. L’accident survient habituellement au domicile, le plus souvent dans la cuisine à la suite d’une chute sur un moyen de cuisson posé au sol. Elles peuvent être inaugurales de la maladie mais surviennent plus souvent chez des patients connus mais au traitement mal suivi. Les conséquences de ces brûlures, toujours profondes, sont souvent dramatiques en termes de séquelles, chez des patients ayant déjà une insertion sociale rendue difficile par l’épilepsie. La prise en charge doit être multidisciplinaire et concerner à la fois la brûlures et l’épilepsie. Des mesures de prévention simples, visant à équilibrer l’épilepsie et éviter au patient de se trouver seul à proximité d’une source de chaleur, doivent être mises en place. PMID:27252613

  11. Complete Genome Sequence of the Frog Pathogen Mycobacterium ulcerans Ecovar Liflandii

    NARCIS (Netherlands)

    Tobias, Nicholas J.; Doig, Kenneth D.; Medema, Marnix H.; Chen, Honglei; Haring, Volker; Moore, Robert; Seemann, Torsten; Stinear, Timothy P.

    In 2004, a previously undiscovered mycobacterium resembling Mycobacterium ulcerans (the agent of Buruli ulcer) was reported in an outbreak of a lethal mycobacteriosis in a laboratory colony of the African clawed frog Xenopus tropicalis. This mycobacterium makes mycolactone and is one of several

  12. Two novel species of rapidly growing mycobacteria: Mycobacterium lehmannii sp. nov. and Mycobacterium neumannii sp. nov.

    Science.gov (United States)

    Nouioui, Imen; Sangal, Vartul; Carro, Lorena; Teramoto, Kanae; Jando, Marlen; Montero-Calasanz, Maria Del Carmen; Igual, José Mariano; Sutcliffe, Iain; Goodfellow, Michael; Klenk, Hans-Peter

    2017-12-01

    Two rapidly growing mycobacteria with identical 16S rRNA gene sequences were the subject of a polyphasic taxonomic study. The strains formed a well-supported subclade in the mycobacterial 16S rRNA gene tree and were most closely associated with the type strain of Mycobacterium novocastrense. Single and multilocus sequence analyses based on hsp65, rpoB and 16S rRNA gene sequences showed that strains SN 1900 T and SN 1904 T are phylogenetically distinct but share several chemotaxonomic and phenotypic features that are are consistent with their classification in the genus Mycobacterium. The two strains were distinguished by their different fatty acid and mycolic acid profiles, and by a combination of phenotypic features. The digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) values for strains SN 1900 T and SN 1904 T were 61.0 % and 94.7 %, respectively; in turn, the corresponding dDDH and ANI values with M. novocastrense DSM 44203 T were 41.4 % and 42.8 % and 89.3 % and 89.5 %, respectively. These results show that strains SN1900 T and SN 1904 T form new centres of taxonomic variation within the genus Mycobacterium. Consequently, strains SN 1900 T (40 T =CECT 8763 T =DSM 43219 T ) and SN 1904 T (2409 T =CECT 8766 T =DSM 43532 T ) are considered to represent novel species, for which the names Mycobacteriumlehmannii sp. nov. and Mycobacteriumneumannii sp. nov. are proposed. A strain designated as 'Mycobacteriumacapulsensis' was shown to be a bona fide member of the putative novel species, M. lehmannii.

  13. Combating highly resistant emerging pathogen Mycobacterium abscessus and Mycobacterium tuberculosis with novel salicylanilide esters and carbamates.

    Science.gov (United States)

    Baranyai, Zsuzsa; Krátký, Martin; Vinšová, Jarmila; Szabó, Nóra; Senoner, Zsuzsanna; Horváti, Kata; Stolaříková, Jiřina; Dávid, Sándor; Bősze, Szilvia

    2015-08-28

    In the Mycobacterium genus over one hundred species are already described and new ones are periodically reported. Species that form colonies in a week are classified as rapid growers, those requiring longer periods (up to three months) are the mostly pathogenic slow growers. More recently, new emerging species have been identified to lengthen the list, all rapid growers. Of these, Mycobacterium abscessus is also an intracellular pathogen and it is the most chemotherapy-resistant rapid-growing mycobacterium. In addition, the cases of multidrug-resistant Mycobacterium tuberculosis infection are also increasing. Therefore there is an urgent need to find new active molecules against these threatening strains. Based on previous results, a series of salicylanilides, salicylanilide 5-chloropyrazinoates and carbamates was designed, synthesized and characterised. The compounds were evaluated for their in vitro activity on M. abscessus, susceptible M. tuberculosis H37Rv, multidrug-resistant (MDR) M. tuberculosis MDR A8, M. tuberculosis MDR 9449/2006 and on the extremely-resistant Praha 131 (XDR) strains. All derivatives exhibited a significant activity with minimum inhibitory concentrations (MICs) in the low micromolar range. Eight salicylanilide carbamates and two salicylanilide esters exhibited an excellent in vitro activity on M. abscessus with MICs from 0.2 to 2.1 μM, thus being more effective than ciprofloxacin and gentamicin. This finding is potentially promising, particularly, as M. abscessus is a threateningly chemotherapy-resistant species. M. tuberculosis H37Rv was inhibited with MICs from 0.2 μM, and eleven compounds have lower MICs than isoniazid. Salicylanilide esters and carbamates were found that they were effective also on MDR and XDR M. tuberculosis strains with MICs ≥1.0 μM. The in vitro cytotoxicity (IC50) was also determined on human MonoMac-6 cells, and selectivity index (SI) of the compounds was established. In general, salicylanilide

  14. Analysis of the leprosy agents Mycobacterium leprae and Mycobacterium lepromatosis in four countries.

    Science.gov (United States)

    Han, Xiang Y; Aung, Fleur M; Choon, Siew Eng; Werner, Betina

    2014-10-01

    To differentiate the leprosy agents Mycobacterium leprae and Mycobacterium lepromatosis and correlate them with geographic distribution and clinicopathologic features. Species-specific polymerase chain reactions were used to detect each bacillus in archived skin biopsy specimens from patients with leprosy from Brazil (n = 52), Malaysia (n = 31), Myanmar (n = 9), and Uganda (n = 4). Findings were correlated with clinical and pathologic data. Etiologic species was detected in 46 of the 52 Brazilian patients, including 36 patients with M leprae, seven with M lepromatosis, and three with both bacilli. The seven patients with sole M lepromatosis all had tuberculoid leprosy, whereas only nine of the 36 patients infected with M leprae exhibited this type, and the rest were lepromatous (P leprae and two with M lepromatosis. Of the Malaysian and Ugandan patients, only M leprae was detected in 27 of the 31 Malaysians and two of the four Ugandans. The leprosy agents vary in geographic distribution. Finding M lepromatosis in Brazil and Myanmar suggests wide existence of this newly discovered species. The leprosy manifestations likely vary with the etiologic agents. Copyright© by the American Society for Clinical Pathology.

  15. [Ecology and transmission of Mycobacterium ulcerans].

    Science.gov (United States)

    Marsollier, L; Aubry, J; Saint-André, J-P; Robert, R; Legras, P; Manceau, A-L; Bourdon, S; Audrain, C; Carbonnelle, B

    2003-10-01

    Mycobacterium ulcerans is an environmental pathogen concerning mainly the tropical countries; it is the causative agent of Buruli ulcer, which has become the third most important mycobacterial disease. In spite of water-linked epidemiological studies to identify the sources of M. ulcerans, the reservoir and the mode of transmission of this organism remain elusive. To determine the ecology and the mode of transmission of M. ulcerans we have set up an experimental model. This experimental model demonstrated that water bugs were able to transmit M. ulcerans by bites. In insects, the bacilli were localized exclusively within salivary glands, where it could both multiply contrary to other mycobacteria species. In another experimental study, we report that the crude extracts from aquatic plants stimulate in vitro the growth of M. ulcerans as much as the biofilm formation by M. ulcerans has been observed on aquatic plants. Given that the water bugs are essentially carnivorous, it is difficult to imagine a direct contact in the contamination of aquatic bugs and plants. It seems very likely that an intermediate host exists. In an endemic area of Daloa in Côte d'Ivoire, our observations were confirmed.

  16. DNA repair in Mycobacterium tuberculosis revisited.

    Science.gov (United States)

    Dos Vultos, Tiago; Mestre, Olga; Tonjum, Tone; Gicquel, Brigitte

    2009-05-01

    Our understanding of Mycobacterium tuberculosis DNA repair mechanisms is still poor compared with that of other bacterial organisms. However, the publication of the first complete M. tuberculosis genome sequence 10 years ago boosted the study of DNA repair systems in this organism. A first step in the elucidation of M. tuberculosis DNA repair mechanisms was taken by Mizrahi and Andersen, who identified homologs of genes involved in the reversal or repair of DNA damage in Escherichia coli and related organisms. Genes required for nucleotide excision repair, base excision repair, recombination, and SOS repair and mutagenesis were identified. Notably, no homologs of genes involved in mismatch repair were identified. Novel characteristics of the M. tuberculosis DNA repair machinery have been found over the last decade, such as nonhomologous end joining, the presence of Mpg, ERCC3 and Hlr - proteins previously presumed to be produced exclusively in mammalian cells - and the recently discovered bifunctional dCTP deaminase:dUTPase. The study of these systems is important to develop therapeutic agents that can counteract M. tuberculosis evolutionary changes and to prevent adaptive events resulting in antibiotic resistance. This review summarizes our current understanding of the M. tuberculosis DNA repair system.

  17. Characterization of Mycobacterium tuberculosis nicotinamidase/pyrazinamidase.

    Science.gov (United States)

    Zhang, Hua; Deng, Jiao-Yu; Bi, Li-Jun; Zhou, Ya-Feng; Zhang, Zhi-Ping; Zhang, Cheng-Gang; Zhang, Ying; Zhang, Xian-En

    2008-02-01

    The nicotinamidase/pyrazinamidase (PncA) of Mycobacterium tuberculosis is involved in the activation of the important front-line antituberculosis drug pyrazinamide by converting it into the active form, pyrazinoic acid. Mutations in the pncA gene cause pyrazinamide resistance in M. tuberculosis. The properties of M. tuberculosis PncA were characterized in this study. The enzyme was found to be a 20.89 kDa monomeric protein. The optimal pH and temperature of enzymatic activity were pH 7.0 and 40 degrees C, respectively. Inductively coupled plasma-optical emission spectrometry revealed that the enzyme was an Mn(2+)/Fe(2+)-containing protein with a molar ratio of [Mn(2+)] to [Fe(2+)] of 1 : 1; furthermore, the external addition of either type of metal ion had no apparent effect on the wild-type enzymatic activity. The activity of the purified enzyme was determined by HPLC, and it was shown that it possessed similar pyrazinamidase and nicotinamidase activity, by contrast with previous reports. Nine PncA mutants were generated by site-directed mutagenesis. Determination of the enzymatic activity and metal ion content suggested that Asp8, Lys96 and Cys138 were key residues for catalysis, and Asp49, His51, His57 and His71 were essential for metal ion binding. Our data show that M. tuberculosis PncA may bind metal ions in a manner different from that observed in the case of Pyrococcus horikoshii PncA.

  18. The transcriptional regulatory network of Mycobacterium tuberculosis.

    Directory of Open Access Journals (Sweden)

    Joaquín Sanz

    Full Text Available Under the perspectives of network science and systems biology, the characterization of transcriptional regulatory (TR networks beyond the context of model organisms offers a versatile tool whose potential remains yet mainly unexplored. In this work, we present an updated version of the TR network of Mycobacterium tuberculosis (M.tb, which incorporates newly characterized transcriptional regulations coming from 31 recent, different experimental works available in the literature. As a result of the incorporation of these data, the new network doubles the size of previous data collections, incorporating more than a third of the entire genome of the bacterium. We also present an exhaustive topological analysis of the new assembled network, focusing on the statistical characterization of motifs significances and the comparison with other model organisms. The expanded M.tb transcriptional regulatory network, considering its volume and completeness, constitutes an important resource for diverse tasks such as dynamic modeling of gene expression and signaling processes, computational reliability determination or protein function prediction, being the latter of particular relevance, given that the function of only a small percent of the proteins of M.tb is known.

  19. Lipid Droplets and Mycobacterium leprae Infection

    Science.gov (United States)

    Elamin, Ayssar A.; Stehr, Matthias; Singh, Mahavir

    2012-01-01

    Leprosy is a chronic infectious disease and is a major source of morbidity in developing countries. Leprosy is caused by the obligate intracellular bacterium Mycobacterium leprae, which infects as primary target Schwann cells. Lepromatous leprosy exhibits multiple lesions of the skin, eyes, nerves, and lymph nodes. The sites of infection are characterized by the presence of foamy macrophages, fully packed with lipid droplets (LDs), which are induced by M. leprae. In the last years, it has become evident that M. tuberculosis imports lipids from foamy macrophages and is dependent on fatty acids for growth in infected macrophages. M. leprae seems to have similar mechanisms for scavenging lipids from the host. But due to the inability to culture M. leprae on laboratory media, research progresses only slowly. However, in the last years, substantial progress has been made in the field of lipid metabolism in M. leprae. Herein, we will present and summarize the lipid droplets formation and the metabolism of lipids during M. leprae infection. PMID:23209912

  20. The cell envelope glycoconjugates of Mycobacterium tuberculosis

    Science.gov (United States)

    Angala, Shiva Kumar; Belardinelli, Juan Manuel; Huc-Claustre, Emilie; Wheat, William H.; Jackson, Mary

    2015-01-01

    Tuberculosis (TB) remains the second most common cause of death due to a single infectious agent. The cell envelope of Mycobacterium tuberculosis (Mtb), the causative agent of the disease in humans, is a source of unique glycoconjugates and the most distinctive feature of the biology of this organism. It is the basis of much of Mtb pathogenesis and one of the major causes of its intrinsic resistance to chemotherapeutic agents. At the same time, the unique structures of Mtb cell envelope glycoconjugates, their antigenicity and essentiality for mycobacterial growth provide opportunities for drug, vaccine, diagnostic and biomarker development, as clearly illustrated by recent advances in all of these translational aspects. This review focuses on our current understanding of the structure and biogenesis of Mtb glycoconjugates with particular emphasis on one of most intriguing and least understood aspect of the physiology of mycobacteria: the translocation of these complex macromolecules across the different layers of the cell envelope. It further reviews the rather impressive progress made in the last ten years in the discovery and development of novel inhibitors targeting their biogenesis. PMID:24915502

  1. Phenotypic assays for Mycobacterium tuberculosis infection.

    Science.gov (United States)

    Song, Ok-Ryul; Deboosere, Nathalie; Delorme, Vincent; Queval, Christophe J; Deloison, Gaspard; Werkmeister, Elisabeth; Lafont, Frank; Baulard, Alain; Iantomasi, Raffaella; Brodin, Priscille

    2017-10-01

    Tuberculosis (TB) is still a major global threat, killing more than one million persons each year. With the constant increase of Mycobacterium tuberculosis strains resistant to first- and second-line drugs, there is an urgent need for the development of new drugs to control the propagation of TB. Although screenings of small molecules on axenic M. tuberculosis cultures were successful for the identification of novel putative anti-TB drugs, new drugs in the development pipeline remains scarce. Host-directed therapy may represent an alternative for drug development against TB. Indeed, M. tuberculosis has multiple specific interactions within host phagocytes, which may be targeted by small molecules. In order to enable drug discovery strategies against microbes residing within host macrophages, we developed multiple fluorescence-based HT/CS phenotypic assays monitoring the intracellular replication of M. tuberculosis as well as its intracellular trafficking. What we propose here is a population-based, multi-parametric analysis pipeline that can be used to monitor the intracellular fate of M. tuberculosis and the dynamics of cellular events such as phagosomal maturation (acidification and permeabilization), zinc poisoning system or lipid body accumulation. Such analysis allows the quantification of biological events considering the host-pathogen interplay and may thus be derived to other intracellular pathogens. © 2017 International Society for Advancement of Cytometry. © 2017 International Society for Advancement of Cytometry.

  2. Inactivation of Mycobacterium avium with free chlorine.

    Science.gov (United States)

    Luh, Jeanne; Mariñas, Benito J

    2007-07-15

    The inactivation kinetics of Mycobacterium avium with free chlorine was characterized by two stages: an initial phase at a relatively fast rate followed by a slower second stage of pseudo first-order kinetics. The inactivation rate of each stage was approximately the same for all experiments performed at a certain condition of pH and temperature; however, variability was observed for the disinfectant exposure at which the transition between the two stages occurred. This variability was not a function of the initial disinfectant concentration, the initial bacterial density, or the bacterial stock. However, the transition to the second stage varied more significantly at high temperatures (30 degrees C), while lower variability was observed at lower temperatures (5 and 20 degrees C). Experiments conducted at pH values in the range of 6-9 revealed that the inactivation of M. avium was primarily due to hypochlorous acid, with little contribution from hypochlorite ion within this pH range. The inactivation kinetics was represented with a two-population model. The activation energies for the resulting pseudo first-order rate constants for the populations with fast and slow kinetics were 100.3 and 96.5 kJ/mol, respectively. The magnitude of these values suggested that for waters of relatively high pH and low temperatures, little inactivation of M. avium would be achieved within treatment plants, providing a seeding source for distribution systems.

  3. Mycobacterium abscessus skin infection after tattooing - Case report*

    Science.gov (United States)

    de Sousa, Pétra Pereira; Cruz, Rossilene Conceição da Silva; Schettini, Antonio Pedro Mendes; Westphal, Danielle Cristine

    2015-01-01

    Mycobacterium abscessus is a rapidly growing mycobacterium that has been affecting people undergoing invasive procedures, such as videosurgery and mesotherapy. This bacterium has global distribution, being found in numerous niches. The frequency of published reports of infection by rapidly growing mycobacteria associated with tattooing procedures has increased in recent years. However, in Brazil there were no case reports of M. abscessus after tattooing in the literature until now. In this paper, we describe the case of a patient with a nine-month history of lesion on a tattoo site. The diagnosis of infection with Mycobacterium abscessus was established by correlation between dermatological and histopathological aspects, culture and molecular biology techniques. The patient had significant improvement of symptoms with the use of clarithromycin monotherapy. PMID:26560222

  4. MYCOBACTERIUM GENAVENSE IN AN AFRICAN PENGUIN (SPHENISCUS DEMERSUS).

    Science.gov (United States)

    Krause, Kristian J; Reavill, Drury; Weldy, Scott H; Bradway, Daniel S

    2015-12-01

    A 19-yr-old female African penguin (Spheniscus demersus) presented with labored breathing and anorexia. Radiographs revealed soft-tissue density lesions in the left lung fields and fluid in the right. The penguin died during the night. Postmortem examination demonstrated multiple granulomas in the lungs and air sacs. The right coelom was filled with opaque fluid. Histopathology of the lung, liver, kidney, and spleen identified Mycobacterium as a primary disease etiology. Large numbers of acid fast-positive, rod-shaped bacteria were recognized on tissue staining. Mycobacterium genavense was detected by polymerase chain reaction (PCR) using primers specific for the species. Further confirmation of M. genavense was accomplished using PCR with universal Mycobacterium spp. primers followed by sequencing of the amplicon obtained. To our knowledge, this is the first reported case of mycobacteriosis-and specifically M. genavense -in an African penguin. This case also demonstrates the similarities of presentation between the more commonly suspected and encountered aspergillosis and mycobacteriosis.

  5. Imaging features of mycobacterium in patients with acquired immunodeficiency syndrome

    International Nuclear Information System (INIS)

    Yang Jun; Sun Yue; Wei Liangui; Xu Yunliang; Li Xingwang

    2013-01-01

    Objective: To analyze the imaging features of mycobacterium in AIDS patients. Methods: Twenty-three cases of mycobacterium tuberculosis and 13 patients of non-tuberculous mycobacteria were proved etiologically and included in this study. All patients underwent X-ray and CT examinations, imaging data were analyzed and compared. Results: The imaging findings of mycobacterium tuberculosis in AIDS patients included consolidation (n = 11), pleural effusion (n = 11), mediastinal lymphadenopathy (n = 11). Pulmonary lesions were always diffuse distribution, and 14 patients of extrapulmonary tuberculosis were found. Pulmonary lesions in non-tuberculous mycobacteria tend to be circumscribed. Conclusions: Non-tuberculous mycobacterial infection in AIDS patients is more common and usually combined with other infections. Imaging features are atypical. (authors)

  6. Aspects épidemiocliniques et évolutifs chez 157 cas de leishmaniose cutanée au Maroc

    Science.gov (United States)

    Hjira, Naoufal; Frikh, Rachid; Marcil, Tarik; Lamsyah, Hanane; Oumakhir, Siham; Baba, Noureddine; Boui, Mohammed

    2014-01-01

    Connue au Maroc depuis la fin du XIX siècle, la leishmaniose cutanée (LC) constitue un problème de santé publique dans notre pays. Le but de notre travail est de décrire le profil épidémioclinique et l’évolution post thérapeutique chez les patients ayant une leishmaniose cutanée dans notre contexte. Nous avons effectué une étude rétrospective, basée sur l'exploitation des dossiers de malades ayant présenté une leishmaniose cutanée confirmée entre janvier 2003 et décembre 2012. Nous avons colligés 157 cas de leishmaniose cutanée. L’âge moyen des patients était de 34.5 ans avec des extrêmes de 6 ans à 63 ans. Le sex-ratio était de 2.34 H/F. La durée d’évolution moyenne des lésions était de 3,6 mois avec des extrêmes de 2 semaines à 10 mois. Les lésions étaient uniques dans 29.5% des cas. Les lésions siégeaient sur membres dans 63%. La forme ulcèro- croûteuse touchait plus de 48%. Le Glucantime était utilisé dans 29.3% des cas, l'azote liquide était utilisé chez 111 autres. L’évolution post-thérapeutique était favorable avec disparition quasi-complète des lésions dans un délai variant de 6 à 10 semaines, au prix de cicatrices inesthétiques chez 14 patients. La leishmaniose cutanée continue à poser un vrai problème de santé publique dans notre pays. L’émergence de formes sévères et résistantes à travers le monde doit inciter à multiplier et renforcer les mesures prophylactiques. PMID:25309671

  7. Serovars of Mycobacterium avium Complex isolated from patients in Denmark

    DEFF Research Database (Denmark)

    Askgaard, D. S.; Giese, Steen Bjørck; Thybo, S.

    1994-01-01

    Danish isolates of Mycobacterium avium complex were serotyped by the use of seroagglutination. The most prevalent serovars among patients with AIDS (n = 89) were 4 and 6, while among non-AIDS patients the most prevalent serovars were 1, 6, and 4, with no major differences between those in patients...... with pulmonary disease (n = 65) and those in patients with lymph node infection (n = 58). The results suggest a Scandinavian distribution of serovars with a predominance of serovar 6 and fail to demonstrate any selective protection against different serovars by Mycobacterium bovis ECG vaccination....

  8. Radiographic differentiation of atypical tuberculosis from mycobacterium tuberculosis

    International Nuclear Information System (INIS)

    Tarver, R.D.; Pearcy, E.A.; Conces, D.J. Jr.; Mathur, P.N.

    1987-01-01

    The chest radiographs of 95 patients with the new diagnosis of atypical turberculosis were reviewed to determine if any significant differences between atypical tuberculosis and that caused by Mycobacterium tuberculosis could be discerned. Findings included upper lobe involvement in B4 of the 95 patients and cavities in 76, with nearly equal groups having no, moderate, or extensive surrounding alveolar disease. Nodules were common; in six patients a nodule was the sole manifestation of disease. Adenopathy was seen in 12 of the 95 patients, atlectasis in 45, pleural thickening in 90, and effusions in three. These radiographic findings did not allow the radiographic differentiation of atypical tuberculosis from Mycobacterium tuberculosis infection

  9. Valorisation de la coupe C4 de vapocraquage via l'hydrogénation du butadiène, l'isomérisation des butènes et la métathèse, en MTBE ou en propylène Upgrading the C4 Cut from Steam Cracking via the Hydrogenation of Butadiene, the Isomerization of Butenes and Metathesis Into Mtbe Or Propylene

    Directory of Open Access Journals (Sweden)

    Chaumette S.

    2006-11-01

    Full Text Available Le surplus de butadiène au niveau mondial contraint les pétrochimistes à recycler la coupe C4 au vapocraqueur. De plus en plus, le butadiène est hydrogéné avant de recraquer toute la coupe. Une fois hydrogénée, cette coupe peut être beaucoup mieux valorisée, soit en MTBE avec isomérisation des n-butènes (procédé ISO-4, soit en propylène et MTBE en utilisant le procédé META-4. L'étude technico-économique montre que cette dernière voie offre la meilleure rentabilité (TRI = 21,5 %. Si le vapocraqueur est intégré à une raffinerie, les butènes peuvent également être transformés en alkylats ou en MTBE, pour répondre à une demande en octane ou en oxygénés pour les carburants. Ces diverses voies de valorisation sont plus intéressantes que la production de MTBE à partir des butanes via la déshydrogénation de l'isobutane ou que la production du propylène par déshydrogénation du propane. Une étude de sensibilité aux différents prix des produits envisagés permet d'établir des courbes d'isorentabilités, délimitant des zones de prix favorables à l'un ou l'autre des produits, pris deux à deux. The evolution of the outlets for C4 cuts from steam cracking shows quite contradictory results. On one hand, European and Asian petrochemists are more constrained to recycle this type of effluent, which contains butadiene and isobutene, to the steam cracker. Likewise, the demand for isobutene for MTBE production is such that it has to be produced by the dehydrogenation of isobutane. This situation is effectively caused by the surplus of butadiene, a by-product of ethylene, and for which the demand is not increasing as fast as the demand for ethylene. To improve cracking performances during the recycling of the C4 Cut, butadiene is more and more selectively hydrogenated. Under these conditions, rather than cracking it, the new processes could make it possible to better upgrade it. Indeed, after selective hydrogenation, most

  10. Immune Responses Involved in Mycobacterium Tuberculosis Infection

    Directory of Open Access Journals (Sweden)

    Roghayeh Teimourpour

    2016-09-01

    Full Text Available Background and Objectives: Mycobacterium tuberculosis is the causative agent of tuberculosis (TB. Approximately one-third of the world's population is infected with M. tuberculosis. Despite the availability of drug and vaccine, it remains one of the leading causes of death in humans especially in developing countries. Epidemiological studies have indicated that only 10-30% of people exposed to tubercle bacillus are infected with M. tuberculosis, and at least 90% of the infected people finally do not acquire TB. The studies have indicated that the host efficient immune system has essential roles in the control of TB infection such that the highest rate of mortality and morbidity is seen in immunocompromised patients such as people infected with HIV. M. tuberculosis is an obligatory intracellular bacterium. It enters the body mainly through the respiratory tract and alveolar macrophages combat this pathogen most commonly. In addition to alveolar macrophages, various T-cell subpopulations need to be activated to overcome this bacterium's resistance to the host defense systems. CD4+ T cells, through production of several cytokines such as IFN-γ and TNF-α, and CD8+ T cells, through cytotoxic activities and induction of apoptosis in infected cells, play critical roles in inducing appropriate immune responses against M. tuberculosis. Although cell-mediated immunity is the cornerstone of host responses against TB and the recent studies have provided evidence for the importance of humoral and innate immune system in the control of TB, a profound understanding of the immune responses would provide a basis for development of new generations of vaccines and drugs. The present study addresses immune responses involved in M. tuberculosis infection.

  11. Nicotine Impairs Macrophage Control of Mycobacterium tuberculosis.

    Science.gov (United States)

    Bai, Xiyuan; Stitzel, Jerry A; Bai, An; Zambrano, Cristian A; Phillips, Matthew; Marrack, Philippa; Chan, Edward D

    2017-09-01

    Pure nicotine impairs macrophage killing of Mycobacterium tuberculosis (MTB), but it is not known whether the nicotine component in cigarette smoke (CS) plays a role. Moreover, the mechanisms by which nicotine impairs macrophage immunity against MTB have not been explored. To neutralize the effects of nicotine in CS extract, we used a competitive inhibitor to the nicotinic acetylcholine receptor (nAChR)-mecamylamine-as well as macrophages derived from mice with genetic disruption of specific subunits of nAChR. We also determined whether nicotine impaired macrophage autophagy and whether nicotine-exposed T regulatory cells (Tregs) could subvert macrophage anti-MTB immunity. Mecamylamine reduced the CS extract increase in MTB burden by 43%. CS extract increase in MTB was also significantly attenuated in macrophages from mice with genetic disruption of either the α7, β2, or β4 subunit of nAChR. Nicotine inhibited autophagosome formation in MTB-infected THP-1 cells and primary murine alveolar macrophages, as well as increased the intracellular MTB burden. Nicotine increased migration of THP-1 cells, consistent with the increased number of macrophages found in the lungs of smokers. Nicotine induced Tregs to produce transforming growth factor-β. Naive mouse macrophages co-cultured with nicotine-exposed Tregs had significantly greater numbers of viable MTB recovered with increased IL-10 production and urea production, but no difference in secreted nitric oxide as compared with macrophages cocultured with unexposed Tregs. We conclude that nicotine in CS plays an important role in subverting macrophage control of MTB infection.

  12. Search for Mycobacterium leprae in wild mammals

    Directory of Open Access Journals (Sweden)

    Sílvia Cristina Barboza Pedrini

    Full Text Available Leprosy is still a worldwide public health problem. Brazil and India show the highest prevalence rates of the disease. Natural infection of armadillos Dasypus novemcinctus with Mycobacterium leprae has been reported in some regions of the United States. Identification of bacilli is difficult, particularly due to its inability to grow in vitro. The use of molecular tools represents a fast and sensitive alternative method for diagnosis of mycobacteriosis. In the present study, the diagnostic methods used were bacilloscopy, histopathology, microbiology, and PCR using specific primers for M. leprae repetitive sequences. PCR were performed using genomic DNA extracted from 138 samples of liver, spleen, lymph nodes, and skin of 44 D. novemcinctus, Euphractus sexcinctus, Cabassous unicinctus, and C. tatouay armadillos from the Middle Western region of the state of São Paulo and from the experimental station of Embrapa Pantanal, located in Pantanal da Nhecolândia of Mato Grosso do Sul state. Also, the molecular analysis of 19 samples from internal organs of other road killed species of wild animals, such as Nasua nasua (ring-tailed coati, Procyon cancrivoros (hand-skinned, Cerdocyon thous (dog-pity-bush, Cavia aperea (restless cavy, Didelphis albiventris (skunk, Sphigurrus spinosus (hedgehog, and Gallictis vittata (ferret showed PCR negative data. None of the 157 analyzed samples had shown natural mycobacterial infection. Only the armadillo inoculated with material collected from untreated multibacillary leprosy patient presented PCR positive and its genomic sequencing revealed 100% identity with M. leprae. According to these preliminary studies, based on the used methodology, it is possible to conclude that wild mammals seem not to play an important role in the epidemiology of leprosy in the Middle Western region of the São Paulo state and in the Pantanal of Mato Grosso do Sul state.

  13. Clonage de l'IGF-I et de son récepteur chez le turbot (Psetta maxima

    Directory of Open Access Journals (Sweden)

    ELIES G.

    1998-07-01

    Full Text Available Les IGF, leurs récepteurs et leurs protéines de liaison constituent une famille moléculaire qui joue un rôle essentiel dans la régulation de la croissance et du développement. Nous nous sommes intéressés à la caractérisation moléculaire de l'IGF-l et de son récepteur (IGF-1R chez le turbot (Psetta maxima, un poisson plat téléostéen. Par RT-PCR, nous avons clone un ADNc codant pour les quatre domaines de l'IGF-l mature. La protéine présente 70 à 96 % d'identité avec les autres IGF-I de vertébrés. Le clonage de la séquence codante entière du récepteur a nécessité la construction d'une banque d'ADNc d'embryons de turbots. Le récepteur est organisé en domaines dont la taille et les caractéristiques sont semblables à celles des autres récepteurs aux IGF de type 1 décrits chez les mammifères et le poulet. La région catalytique est particulièrement conservée. Dans certains domaines, notamment dans la région C-terminale du précurseur, quelques différences qui pourraient avoir une importance fonctionnelle sont cependant observées. Enfin, par RT-PCR, nous avons mis en évidence une régulation ontogénique du statut de polyadénylation des ARNm IGF-1R.

  14. Food security among individuals experiencing homelessness and mental illness in the At Home/Chez Soi Trial.

    Science.gov (United States)

    O'Campo, Patricia; Hwang, Stephen W; Gozdzik, Agnes; Schuler, Andrée; Kaufman-Shriqui, Vered; Poremski, Daniel; Lazgare, Luis Ivan Palma; Distasio, Jino; Belbraouet, Slimane; Addorisio, Sindi

    2017-08-01

    Individuals experiencing homelessness are particularly vulnerable to food insecurity. The At Home/Chez Soi study provides a unique opportunity to first examine baseline levels of food security among homeless individuals with mental illness and second to evaluate the effect of a Housing First (HF) intervention on food security in this population. At Home/Chez Soi was a 2-year randomized controlled trial comparing the effectiveness of HF compared with usual care among homeless adults with mental illness, stratified by level of need for mental health services (high or moderate). Logistic regressions tested baseline associations between food security (US Food Security Survey Module), study site, sociodemographic variables, duration of homelessness, alcohol/substance use, physical health and service utilization. Negative binomial regression determined the impact of the HF intervention on achieving levels of high or marginal food security over an 18-month follow-up period (6 to 24 months). Community settings at five Canadian sites (Moncton, Montreal, Toronto, Winnipeg and Vancouver). Homeless adults with mental illness (n 2148). Approximately 41 % of our sample reported high or marginal food security at baseline, but this figure varied with gender, age, mental health issues and substance use problems. High need participants who received HF were more likely to achieve marginal or high food security than those receiving usual care, but only at the Toronto and Moncton sites. Our large multi-site study demonstrated low levels of food security among homeless experiencing mental illness. HF showed promise for improving food security among participants with high levels of need for mental health services, with notable site differences.

  15. Dépression et niveau de fardeau chez les aidants familiaux des sujets déments en Tunisie

    Science.gov (United States)

    Ben Thabet, Jihène; Jaoua, Feriel; Charfi, Nada; Zouari, Lobna; Zouari, Nasreddine; Maalej, Mohamed

    2011-01-01

    Introduction La démence peut retentir lourdement sur les aidants familiaux du patient. Les objectifs de notre étude étaient de déterminer le niveau de fardeau et de la dépression chez les aidants familiaux de sujets déments, et d'identifier les facteurs associés à un niveau de fardeau élevé. Méthodes Il s'agissait d'une enquête auprès de 65 aidants tunisiens. Les niveaux de fardeau et de la dépression ont été évalués par, respectivement, l'inventaire de Zarit et l’échelle de Beck. Résultats Le taux des aidants qui avaient un niveau de fardeau élevé était de 52,3 %. Une dépression modérée ou sévère a été relevée chez 46,2 %. Un niveau de fardeau élevé était corrélé, du côté de l'aidant, avec le niveau socio-économique moyen à élevé, la cohabitation avec le patient, le fait d’être son conjoint, la réduction des activités quotidiennes et la sévérité de la dépression, et, du côté du dément, avec l'agressivité. Conclusion Les facteurs corrélés à un niveau de fardeau élevé orientent vers les cibles d'intervention et sont susceptibles d’être améliorés par la prise en charge, ce qui contribuerait à alléger la détresse des aidants. PMID:22384291

  16. Expression of Mycobacterium smegmatis pyrazinamidase in Mycobacterium tuberculosis confers hypersensitivity to pyrazinamide and related amides.

    Science.gov (United States)

    Boshoff, H I; Mizrahi, V

    2000-10-01

    A pyrazinamidase (PZase)-deficient pncA mutant of Mycobacterium tuberculosis, constructed by allelic exchange, was used to investigate the effects of heterologous amidase gene expression on the susceptibility of this organism to pyrazinamide (PZA) and related amides. The mutant was highly resistant to PZA (MIC, >2,000 microg/ml), in accordance with the well-established role of pncA in the PZA susceptibility of M. tuberculosis (A. Scorpio and Y. Zhang, Nat. Med. 2:662-667, 1996). Integration of the pzaA gene encoding the major PZase/nicotinamidase from Mycobacterium smegmatis (H. I. M. Boshoff and V. Mizrahi, J. Bacteriol. 180:5809-5814, 1998) or the M. tuberculosis pncA gene into the pncA mutant complemented its PZase/nicotinamidase defect. In both pzaA- and pncA-complemented mutant strains, the PZase activity was detected exclusively in the cytoplasm, suggesting an intracellular localization for PzaA and PncA. The pzaA-complemented strain was hypersensitive to PZA (MIC, /=20 microg/ml) and was also sensitive to benzamide (MIC, 20 microg/ml), unlike the wild-type and pncA-complemented mutant strains, which were highly resistant to this amide (MIC, >500 microg/ml). This finding was consistent with the observation that benzamide is hydrolyzed by PzaA but not by PncA. Overexpression of PzaA also conferred sensitivity to PZA, nicotinamide, and benzamide on M. smegmatis (MIC, 150 microg/ml in all cases) and rendered Escherichia coli hypersensitive for growth at low pH.

  17. Effect of chlorine on Mycobacterium gordonae and Mycobacterium chubuense in planktonic and Biofilm State

    Directory of Open Access Journals (Sweden)

    Alejandra Soledad Oriani

    2018-01-01

    Full Text Available Background: There is evidence that drinking water could be a source of infections with pathogenic nontuberculous mycobacteria (NTM potentially risky to human health. The aim was to investigate the resistance of two NTM isolated from drinking water, Mycobacterium gordonae and Mycobacterium chubuense, at different concentrations of chlorine (as sodium hypochlorite, used in drinking water sanitation. Methods: The NTM were grown in suspension and in biofilms and were challenged with biocide for 10 and 60 min. Results: To obtain 7-log reduction from the initial population of M. chubuense, in the planktonic state, there were necessary 20 ppm of chorine and 60 min of exposure. The same effect was achieved in M. gordonae with 10 ppm for the same period. The maximum reduction of both NTM in biofilm was 3-log reduction and was achieved using 30 ppm for 60 min. The chlorine susceptibility of cells in biofilms was significantly lower than that of planktonic cells. The results highlight the resistance of both NTM to the concentrations used in routine water sanitation (0.2 ppm according to Argentine Food Code. Differences in chlorine resistance found between the two NTM in planktonic growth decrease when they are grown in biofilm. Conclusion: This suggests that current water disinfection procedures do not always achieve effective control of NTM in the public supply system, with the consequent health risk to susceptible population, and the need to take into account biofilms, because of their deep consequences in the way to analyze the survival of prokaryotic cells in different environments.

  18. Insights on the Emergence of Mycobacterium tuberculosis from the Analysis of Mycobacterium kansasii

    Science.gov (United States)

    Wang, Joyce; McIntosh, Fiona; Radomski, Nicolas; Dewar, Ken; Simeone, Roxane; Enninga, Jost; Brosch, Roland; Rocha, Eduardo P.; Veyrier, Frédéric J.; Behr, Marcel A.

    2015-01-01

    By phylogenetic analysis, Mycobacterium kansasii is closely related to Mycobacterium tuberculosis. Yet, although both organisms cause pulmonary disease, M. tuberculosis is a global health menace, whereas M. kansasii is an opportunistic pathogen. To illuminate the differences between these organisms, we have sequenced the genome of M. kansasii ATCC 12478 and its plasmid (pMK12478) and conducted side-by-side in vitro and in vivo investigations of these two organisms. The M. kansasii genome is 6,432,277 bp, more than 2 Mb longer than that of M. tuberculosis H37Rv, and the plasmid contains 144,951 bp. Pairwise comparisons reveal conserved and discordant genes and genomic regions. A notable example of genomic conservation is the virulence locus ESX-1, which is intact and functional in the low-virulence M. kansasii, potentially mediating phagosomal disruption. Differences between these organisms include a decreased predicted metabolic capacity, an increased proportion of toxin–antitoxin genes, and the acquisition of M. tuberculosis-specific genes in the pathogen since their common ancestor. Consistent with their distinct epidemiologic profiles, following infection of C57BL/6 mice, M. kansasii counts increased by less than 10-fold over 6 weeks, whereas M. tuberculosis counts increased by over 10,000-fold in just 3 weeks. Together, these data suggest that M. kansasii can serve as an image of the environmental ancestor of M. tuberculosis before its emergence as a professional pathogen, and can be used as a model organism to study the switch from an environmental opportunistic pathogen to a professional host-restricted pathogen. PMID:25716827

  19. Generalized Tuberculosis in Llamas (Lama glama) Due to Mycobacterium microti

    Science.gov (United States)

    Oevermann, A.; Pfyffer, G. E.; Zanolari, P.; Meylan, M.; Robert, N.

    2004-01-01

    Necropsy of two llamas revealed numerous caseous nodules containing abundant acid-fast bacilli (AFB) in various organs. The AFB were identified by spoligotyping as Mycobacterium microti, vole type. Infection caused by M. microti should be considered in the differential diagnosis of debilitating diseases in New World camelids. PMID:15071059

  20. Cytochemical and biological properties of Mycobacterium bovis BCG.

    Science.gov (United States)

    Slosárek, M

    1977-01-01

    It was the aim of the present communication to find a simple test for a reliable discrimination of Mycobacterium bovis BCG from Mycobacterium tuberculosis. A total of 26 BCG strains, out of them 10 Czechoslovak strains (2 lyophilized cultures of BCG of different batch, 6 strains isolated from abscesses of children after BCG-vaccination and 2 strains from fatal cases after BCG-vaccination) and 16 strains obtained from foreign laboratories, were used. Of the tested characteristics a combination of 3 tests, sensitivity to 1 microgram of 2-thiophene carbonylhydrazide (TCH), activity of 3 acylamidases (urease, nicotinamidase and pyrazinamidase) and a quantitative nitrate test, was found to be most advantageous. The Czechoslovak strains of Mycobacterium bovis BCG were fully sensitive to TCH, of the 3 acylamidases mentioned above only urease was positive and nitrate was reduced only little or not at all. On the other hand, strains of Mycobacterium tuberculosis were always resistant to TCH, had positive urease, nicotinamidase and pyrazinamidase and reduced nitrate very intensively.

  1. Mycobacterium tuberculosis infection of domesticated Asian elephants, Thailand.

    OpenAIRE

    2011-01-01

    Four Asian elephants were confirmed to be infected with Mycobacterium tuberculosis by bacterial culture, other diagnostic procedures, and sequencing of 16S–23S rDNA internal transcribed spacer region, 16S rRNA, and gyrase B gene sequences. Genotyping showed that the infectious agents originated from 4 sources in Thailand. To identify infections, a combination of diagnostic assays is essential.

  2. Mycobacterium avium subsp. paratuberculosis infection, immunology and pathology of livestock

    Science.gov (United States)

    Mycobacterium avium subsp. paratuberculosis (MAP) infection in ruminants leads to a chronic and progressive enteric disease (Johne’s disease) that results in loss of intestinal function, poor body condition, and eventual death. Transmission is primarily through a fecal-oral route in neonates but con...

  3. Mycobacterium bovis hip bursitis in a lung transplant recipient.

    Science.gov (United States)

    Dan, J M; Crespo, M; Silveira, F P; Kaplan, R; Aslam, S

    2016-02-01

    We present a report of extrapulmonary Mycobacterium bovis infection in a lung transplant recipient. M. bovis is acquired predominantly by zoonotic transmission, particularly from consumption of unpasteurized foods. We discuss epidemiologic exposure, especially as relates to the Mexico-US border, clinical characteristics, resistance profile, and treatment. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Siderocalin inhibits the intracellular replication of Mycobacterium tuberculosis in macrophages

    DEFF Research Database (Denmark)

    Johnson, Erin E; Srikanth, Chittur V; Sandgren, Andreas

    2010-01-01

    Siderocalin is a secreted protein that binds to siderophores to prevent bacterial iron acquisition. While it has been shown to inhibit the growth of Mycobacterium tuberculosis (M.tb) in extracellular cultures, its effect on this pathogen within macrophages is not clear. Here, we show that sideroc...

  5. Clinical manifestations, diagnosis, and treatment of Mycobacterium haemophilum infections.

    NARCIS (Netherlands)

    Lindeboom, J.A.; Bruijnesteijn van Coppenraet, L.E.; Soolingen, D. van; Prins, J.M.; Kuijper, E.J.

    2011-01-01

    Mycobacterium haemophilum is a slowly growing acid-fast bacillus (AFB) belonging to the group of nontuberculous mycobacteria (NTM) frequently found in environmental habitats, which can colonize and occasionally infect humans and animals. Several findings suggest that water reservoirs are a likely

  6. Clinical manifestations, diagnosis, and treatment of Mycobacterium haemophilum infections

    NARCIS (Netherlands)

    Lindeboom, J.A.; Bruijnesteijn van Coppenraet, L.E.S.; van Soolingen, D.; Prins, J.M.; Kuijper, E.J.

    2011-01-01

    Mycobacterium haemophilum is a slowly growing acid-fast bacillus (AFB) belonging to the group of nontuberculous mycobacteria (NTM) frequently found in environmental habitats, which can colonize and occasionally infect humans and animals. Several findings suggest that water reservoirs are a likely

  7. Sensitivity of Mycobacterium bovis to common beef processing interventions

    Science.gov (United States)

    Objective. Mycobacterium bovis is the causative agent of bovine tuberculosis, a relevant zoonosis that can spread to humans through inhalation or by ingestion. M. bovis multiplies slowly, so infected animals may be sent to slaughter during the early stages of the disease before diagnosis and when ...

  8. Polymerase chain reaction for the detection of Mycobacterium leprae

    NARCIS (Netherlands)

    Hartskeerl, R. A.; de Wit, M. Y.; Klatser, P. R.

    1989-01-01

    A polymerase chain reaction (PCR) using heat-stable Taq polymerase is described for the specific detection of Mycobacterium leprae, the causative agent of leprosy. A set of primers was selected on the basis of the nucleotide sequence of a gene encoding the 36 kDa antigen of M. leprae. With this set

  9. Transmission of Mycobacterium tuberculosis Undetected by Tuberculin Skin Testing

    Czech Academy of Sciences Publication Activity Database

    Anderson, S. T.; Williams, A. J.; Brown, J. R.; Newton, S. M.; Šimšová, Marcela; Nicol, M. P.; Šebo, Peter; Levin, M.; Wilkinson, R. J.; Wilkinson, K. A.

    2006-01-01

    Roč. 173, - (2006), s. 1038-1042 ISSN 1073-449X R&D Projects: GA AV ČR IAA5020406 Institutional research plan: CEZ:AV0Z50200510 Keywords : adenylate cyclase * diagnostic tests and procedures * mycobacterium tuberculosis Subject RIV: EE - Microbiology, Virology Impact factor: 9.091, year: 2006

  10. Microevolution of Mycobacterium tuberculosis in a tuberculosis patient.

    NARCIS (Netherlands)

    Al-Hajoj, S.A.; Akkerman, O.; Parwati, I.; Al-Gamdi, S.; Rahim, Z.; Soolingen, D. van; Ingen, J. van; Supply, P.; Zanden, A.G. van der

    2010-01-01

    Five Mycobacterium tuberculosis isolates were obtained from three body sites from a Dutch patient. The isolates displayed a single genotype by 24-locus MIRU-VNTR typing (except for a single locus not amplified from one isolate) but were differentiated by small variations in IS6110 fingerprints,

  11. Structural studies on Mycobacterium tuberculosis RecA

    Indian Academy of Sciences (India)

    Structures of crystals of Mycobacterium tuberculosis RecA, grown and analysed under different conditions, provide insights into hitherto underappreciated details of molecular structure and plasticity. In particular, they yield information on the invariant and variable features of the geometry of the P-loop, whose binding to ATP ...

  12. The Use Of Rap-PCR In Studying Mycobacterium tuberculosis ...

    African Journals Online (AJOL)

    Mycobacterium tuberculosis is the second leading cause of death from infectious agent. This study sought to detect M. tuberculosis genes, which were specifically expressed, or upregulated during intracellular infection of. J774 murine macrophages; as such genes may be potential targets for novel drug action. J774 murine ...

  13. Construction of an internal amplification control for Mycobacterium ...

    African Journals Online (AJOL)

    Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis (MTB) which mostly affects the lungs. The disease causes deaths of many people every year. There are different methods to detect MTB such as skin test, staining, culture and molecular techniques. Polymerase chain reaction (PCR) is a ...

  14. Modern lineages of Mycobacterium tuberculosis in Addis Ababa ...

    African Journals Online (AJOL)

    Background: The genotyping of Mycobacterium tuberculosis strains is important to have unique insights into the dissemination dynamics and evolutionary genetics of this pathogen and for TB control as it allows the detection of suspected outbreaks and the tracing of transmission chains. Objective: To characterize M.

  15. Beijing/W genotype Mycobacterium tuberculosis and drug resistance.

    NARCIS (Netherlands)

    Glynn, Judith R; Kremer, Kristin; Borgdorff, Martien W; Rodriguez, Mar Pujades; Soolingen, Dick van

    2006-01-01

    Beijing/W genotype Mycobacterium tuberculosis is widespread, may be increasing, and may have a predilection for drug resistance. Individual-level data on >29,000 patients from 49 studies in 35 countries were combined to assess the Beijing genotype's prevalence worldwide, trends over time and with

  16. Disseminated Mycobacterium avium complex in an immunocompetent host

    Directory of Open Access Journals (Sweden)

    Joseph M Yabes

    2017-01-01

    Full Text Available Disseminated Mycobacterium avium complex (DMAC has historically been described in the immunocompromised. The current epidemiologic research suggests that the incidence of nontuberculous mycobacterial infections is increasing. We present a case of DMAC infection manifesting as hepatic granulomas in a 35-year-old immunocompetent female. This case suggests DMAC infection in a patient without traditional epidemiological risk factors.

  17. The transmission of Mycobacterium tuberculosis in high burden settings

    NARCIS (Netherlands)

    Yates, Tom A.; Khan, Palwasha Y.; Knight, Gwenan M.; Taylor, Jonathon G.; McHugh, Timothy D.; Lipman, Marc; White, Richard G.; Cohen, Ted; Cobelens, Frank G.; Wood, Robin; Moore, David A. J.; Abubakar, Ibrahim

    2016-01-01

    Unacceptable levels of Mycobacterium tuberculosis transmission are noted in high burden settings and a renewed focus on reducing person-to-person transmission in these communities is needed. We review recent developments in the understanding of airborne transmission. We outline approaches to measure

  18. Cloning and expression of mce1A gene from Mycobacterium ...

    African Journals Online (AJOL)

    Background: Tuberculosis remains the leading cause of death in the world, especially wherever poverty, malnutrition and poor housing prevail. Mycobacterium tuberculosis Beijing strain is the most common strain that causes tuberculosis in Indonesia. The wide spread of tuberculosis has been further aggravated by ...

  19. Identification of Mycobacterium avium subsp. hominissuis Isolated From Drinking Water

    Science.gov (United States)

    Mycobacterium avium (MA) is divided into four subspecies based primarily on host-range and consists of MA subsp. avium (birds), MA subsp. silvaticum (wood pigeons), MA subsp. paratuberculosis (broad, poorly-defined host range), and the recently described MA subsp. hominissuis (hu...

  20. Prevalence of Mycobacterium bovis in Cattle Slaughtered at Sokoto ...

    African Journals Online (AJOL)

    This study was undertaken to screen cattle slaughtered at the Sokoto Central Abattoir for antibodies against Mycobacterium bovis. By the lateral flow technique (immunochromatography), using monoclonal antibodies for M. bovis (BioNote, Inc. Gyeonggi-do, Korea) and by post mortem examination. A total of 194 slaughtered ...

  1. Advances in the Laboratory Diagnosis of Mycobacterium Tuberculosis

    African Journals Online (AJOL)

    Mycobacterium tuberculosis (MTB), the agent of human tuberculosis remains a leading cause of mortality globally. Its resurgence during the last two decades is a reflection of its opportunistic relationship with HIV. The challenges associated with the disease are enormous and often debilitating. The role of clinical and ...

  2. Adaptation and evolution of drug-resistant Mycobacterium tuberculosis

    NARCIS (Netherlands)

    Bergval, I.L.

    2013-01-01

    Many studies have been conducted on drug resistance and the evolution of Mycobacterium tuberculosis. Notwithstanding, many molecular mechanisms facilitating the emergence, adaptation and spread of drug-resistant tuberculosis have yet to be discovered. This thesis reports studies of the adaptive

  3. BACTEC MGIT 960 TM system for screening of Mycobacterium ...

    African Journals Online (AJOL)

    This study was aimed to evaluate the recent technique (BACTEC MGIT 960 TM system) for screening of Mycobacterium tuberculosis complex among cattle in Egypt. From the 1180 cattle examined in three different Governorates (El-Sharkia, El-Gharbia and El-Monefeia) by single intradermal tuberculin test, 29 animals ...

  4. Degradation of morpholine by Mycobacterium sp. isolated from ...

    African Journals Online (AJOL)

    The biodegradation of morpholine has attracted much interest because morpholine causes environmental pollution. Ten species belonging to nine genera were tested for their abilities to degrade morpholine in mineral salts medium containing morpholine (1 g/l). Mycobacterium sp. isolated from polluted water sample ...

  5. Acanthamoeba Sp. S-11 phagocytotic activity on Mycobacterium ...

    African Journals Online (AJOL)

    Background: Mycobacterium leprae (M. leprae) is a pathogenic bacterium that causes leprosy. The presence of M. leprae in the environment is supported by microorganisms that act as the new host for M. leprae. Acanthamoeba's potential to be a host of M. leprae in the environment. Acanthamoeba sp. is Free Living ...

  6. Transmissie van Mycobacterium bovis tussen mens en dier

    NARCIS (Netherlands)

    Vries, de G.; Beer, de J.; Bakker, D.; Soolingen, D.

    2015-01-01

    Nederland is officieel vrij van rundertuberculose. Toch komt af en toe nog Mycobacterium bovis-tuberculose voor bij relatief jonge autochtone Nederlanders. Ook zijn er recent nog wel boviene-uitbraken geweest. Dat roept de vraag op of er ook nu nog transmissie is van M.bovis tussen mens en dier.

  7. MYCOBACTERIUM AVIUM AND DRINKING WATER WHAT ARE THE CONNECTIONS?

    Science.gov (United States)

    Background: Human Mycobacterium avium infections are only known to be acquired from environmental sources such as water and soil. We compared M. avium isolates from clinical and drinking water sources using molecular tools. Methods: M. avium was isolated from water samples colle...

  8. Tuberkulose forårsaget af Mycobacterium africanum

    DEFF Research Database (Denmark)

    Bek, Dorte; Kjeldsen, Marianne Kirstine; Hansen, Nikolaj Friis

    2010-01-01

    Tuberkulose (TB) forårsages af patogene arter fra Mycobacterium tuberculosis komplekset (MTBC) og har en incidens på cirka 7/100.000 i Danmark. På mistanke om TB hos en akut indlagt 40 årig afrikansk mand initieredes anti-TB behandling. Efter 13 timers indlæggelse afgik patienten ved døden. Fra...

  9. Host immunity to Mycobacterium tuberculosis and risk of tuberculosis

    DEFF Research Database (Denmark)

    Michelsen, Sascha Wilk; Soborg, Bolette; Agger, Else-Marie

    2016-01-01

    BACKGROUND: Human immune responses to latent Mycobacterium tuberculosis (Mtb) infection (LTBI) may enable individuals to control Mtb infection and halt progression to tuberculosis (TB), a hypothesis applied in several novel TB vaccines. We aimed to evaluate whether immune responses to selected LTBI...

  10. Benzothiazinones kill Mycobacterium tuberculosis by blocking arabinan synthesis

    DEFF Research Database (Denmark)

    Makarov, Vadim; Manina, Giulia; Mikusova, Katarina

    2009-01-01

    New drugs are required to counter the tuberculosis (TB) pandemic. Here, we describe the synthesis and characterization of 1,3-benzothiazin-4-ones (BTZs), a new class of antimycobacterial agents that kill Mycobacterium tuberculosis in vitro, ex vivo, and in mouse models of TB. Using genetics...

  11. A case of Manila type Mycobacterium tuberculosis infection in Japan

    Science.gov (United States)

    Usami, Osamu; Nakajima, Chie; Endo, Shiro; Inomata, Shinya; Kanamori, Hajime; Hirakata, Yoichi; Uchiyama, Bine; Kaku, Mitsuo; Suzuki, Yasuhiko; Hattori, Toshio

    2015-01-01

    Key Clinical Message A 76-year-old Japanese woman contracted a Mycobacterium tuberculosis (TB, Manila type) infection in Japan, despite never having traveled. However, her son was treated for TB in the Philippines 3 years before he stayed at her house. Spoligotyping allows us to identify the TB genotype and identify the route of infection. PMID:26273455

  12. La double-page chez Hirohiko Araki : l’ubris faite norme

    Directory of Open Access Journals (Sweden)

    Aurélien Pigeat

    2011-03-01

    Full Text Available Le style d’Araki se caractérise par un usage massif de la double-page, loin de l’usage ponctuel que l’on trouve habituellement dans les shonen. Elle témoigne d’une forme d’ubris qui se fait norme de composition c’est-à-dire qu’elle érige le principe de débordement en règle de structuration de l’action et des planches Elle est ainsi la marque de la démesure d’un auteur qui, sous l’apparence du manga populaire, et à travers les codes de ce dernier, élabore une œuvre d’une puissance et d’une sophistication rares..

    Pour appréhender ce phénomène, il nous faut d’abord observer concrètement l’usage que fait Hirohiko Araki de la double-page, les lieux du récit que celle-ci investit, la fréquence de ses manifestations, et la manière dont elle caractérise les différentes parties de la saga Jojo’s bizarre Adventure. L’ubris de la double-page met alors particulièrement en relief deux éléments centraux de la poétique d’Hirohiko Araki : le corps et le temps.  La double-page apparaît comme la réponse matérielle à ces corps qui débordent de la page classique, qui éclatent ou se dispersent de telle sorte que l’auteur doit étendre les limites de ce cadre pour les représenter. Le temps entre lui en scène à travers le détail : la double-page devient le règne d’un détail sur lequel le lecteur passe trop vite et auquel le héros accorde toute son attention. Enfin, la double-page possède chez Hirohiko Araki une dimension proprement esthétique que révèle clairement l’usage presque absolu qui en est fait dans la septième partie de Jojo’s bizarre Adventure, Steel Ball Run, et dans le volume Rohan au Louvre, même si l’on peut la deviner déjà auparavant. La double-page est un moment où l’énigme se présente au héros, se met en mouvement ou se trouve élucidée. Le règne de l’ubris s’affirme là, dans ces doubles-pages qui n’en sont finalement plus, dans cette

  13. Les dysthyroïdies chez l’hémodialysé chronique

    Directory of Open Access Journals (Sweden)

    Najoua Zbiti

    2010-10-01

    Full Text Available INTRODUCTION: Les dysthyroïdies chez l’hémodialysé chronique sont représentées par une hypothyroïdie: dite le syndrome de basse T3, actuellement nommée "le syndrome de la maladie euthyroïdienne". L’objectif de notre travail est de déterminer le profil thyroïdien de nos HDC afin de préciser la prévalence des différents troubles thyroïdiens dans notre population et de dégager les facteurs prédictifs, aussi on a précisé l’évolution sur une période de 3 ans. METHODES: Il s’agit d’une étude rétrospective réalisée en Mars 2007 concernant 68 patients adultes en hémodialyse périodique. Nous avons analysé les paramètres anthropométriques, cliniques et biologiques. Le dosage des hormones thyroïdiennes ((triiodothyronine libre FT3, (thyroxine libre FT4 et (thyréostimuline ultra-sensible TSHus s’est effectué selon la méthode radio-immunologique. Nous avons comparé 2 groupes de patients avec et sans dysthyroïdie (définie par un taux anormal de FT3 et/ou de FT4 et/ou de TSH afin de dégager les facteurs de risque. On a réalisé une surveillance biologique des hormones thyroïdiennes pendant 3 ans afin de préciser l’incidence des différents troubles thyroïdiens dans la même population. RESULTATS: Tous les patients sont en euthyroïdie clinique. On n’a noté aucun cas de goitre. Le profil thyroïdien est caractérisé par une hypothyroïdie biologique, la prévalence était de 28%. Nous n'avons pas trouvé des cas d'hyperthyroïdie. L'étude comparative des deux groupes de malades biologiquement euthyroïdiens et hypothyroïdiens a révèle le syndrome inflammatoire (p=0.001, l’âge avancé (p=0.003, et la durée prolongée en hémodialyse (p=0.04 comme des facteurs de risque liés à l’hypothyroïdie biologique. Deux HDC ont nécessité un traitement hormonal substitutif vu le contexte du diabète dans un cas et de la grossesse dans l’autre cas. Le suivi biologique pendant trois ans n’a r

  14. Comparaison de différentes associations d'anticoagulants sur les numérations plaquettaires et la formation d'agrégats chez le chat

    OpenAIRE

    Charru, Pauline

    2011-01-01

    Chez le chat, l'hémogramme est un examen complémentaire parfois difficile à interpréter aux vues des nombreuses difficultés d'ordre pré-analytique et analytique potentielle. Parmi elles, on retiendra la forte tendance des plaquettes à s'agréger in vitro, surtout sur EDTA-dépendante, une nouvelle molécule antiagrégante a montré son intérêt : le CTAD (Citrate, Théophylline, Adénosine et Dipyridamole). Dans notre étude, l'utilisation de l'association EDTA et CTAD chez 46 chats sains, en éliminan...

  15. Detection of Mycobacterium chelonae, Mycobacterium abscessus Group, and Mycobacterium fortuitum Complex by a Multiplex Real-Time PCR Directly from Clinical Samples Using the BD MAX System.

    Science.gov (United States)

    Rocchetti, Talita T; Silbert, Suzane; Gostnell, Alicia; Kubasek, Carly; Campos Pignatari, Antonio C; Widen, Raymond

    2017-03-01

    A new multiplex PCR test was designed to detect Mycobacterium chelonae, Mycobacterium abscessus group, and Mycobacterium fortuitum complex on the BD MAX System. A total of 197 clinical samples previously submitted for mycobacterial culture were tested using the new protocol. Samples were first treated with proteinase K, and then each sample was inoculated into the BD MAX Sample Buffer Tube. Extraction and multiplex PCR were performed by the BD MAX System, using the BD MAX ExK TNA-3 extraction kit and BD TNA Master Mix, along with specific in-house designed primers and probes for each target. The limit of detection of each target, as well as specificity, was evaluated. Of 197 clinical samples included in this study, 133 were positive and 60 were negative for mycobacteria by culture, and another 4 negative samples were spiked with M. chelonae ATCC 35752. The new multiplex PCR on the BD MAX had 97% concordant results with culture for M. abscessus group detection, 99% for M. chelonae, and 100% for M. fortuitum complex. The new multiplex PCR test performed on the BD MAX System proved to be a sensitive and specific test to detect M. chelonae, M. abscessus group, and M. fortuitum complex by real-time PCR on an automated sample-in results-out platform. Copyright © 2017 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

  16. Organization of the origins of replication of the chromosomes of Mycobacterium smegmatis, Mycobacterium leprae and Mycobacterium tuberculosis and isolation of a functional origin from M. smegmatis.

    Science.gov (United States)

    Salazar, L; Fsihi, H; de Rossi, E; Riccardi, G; Rios, C; Cole, S T; Takiff, H E

    1996-04-01

    The genus Mycobacterium is composed of species with widely differing growth rates ranging from approximately three hours in Mycobacterium smegmatis to two weeks in Mycobacterium leprae. As DNA replication is coupled to cell duplication, it may be regulated by common mechanisms. The chromosomal regions surrounding the origins of DNA replication from M. smegmatis, M. tuberculosis, and M. leprae have been sequenced, and show very few differences. The gene order, rnpA-rpmH-dnaA-dnaN-recF-orf-gyrB-gyrA, is the same as in other Gram-positive organisms. Although the general organization in M. smegmatis is very similar to that of Streptomyces spp., a closely related genus, M. tuberculosis and M. leprae differ as they lack an open reading frame, between dnaN and recF, which is similar to the gnd gene of Escherichia coli. Within the three mycobacterial species, there is extensive sequence conservation in the intergenic regions flanking dnaA, but more variation from the consensus DnaA box sequence was seen than in other bacteria. By means of subcloning experiments, the putative chromosomal origin of replication of M. smegmatis, containing the dnaA-dnaN region, was shown to promote autonomous replication in M. smegmatis, unlike the corresponding regions from M. tuberculosis or M. leprae.

  17. Infections with Mycobacterium tuberculosis and Mycobacterium avium among HIV-infected patients after the introduction of highly active antiretroviral therapy. EuroSIDA Study Group JD

    DEFF Research Database (Denmark)

    Kirk, O; Gatell, J M; Mocroft, A

    2000-01-01

    the introduction of HAART, using data from the EuroSIDA study, a European, multicenter observational cohort of more than 7,000 patients. Overall incidences of Mycobacterium tuberculosis (TB) and Mycobacterium avium complex (MAC) were 0.8 and 1.4 cases/100 person-years of follow-up (PYF), decreasing from 1.8 (TB...

  18. Detection of Mycobacterium bovis and Mycobacterium tuberculosis from Cattle: Possible Public Health Relevance

    DEFF Research Database (Denmark)

    Thakur, Aneesh; Sharma, Mandeep; Katoch, Vipin C.

    2012-01-01

    Mycobacterium bovis and Mycobacterium tuberculosis infect both animals and humans. The disease epidemiology by these agents differs in developed and developing countries due to the differences in the implementation of the prevention and control strategies. The present study describes the detectio...

  19. Comparative Genomics and Proteomic Analysis of Four Non-tuberculous Mycobacterium Species and Mycobacterium tuberculosis Complex : Occurrence of Shared Immunogenic Proteins

    NARCIS (Netherlands)

    Gcebe, Nomakorinte; Michel, Anita; Gey van Pittius, Nicolaas C; Rutten, Victor

    2016-01-01

    The Esx and PE/PPE families of proteins are among the most immunodominant mycobacterial antigens and have thus been the focus of research to develop vaccines and immunological tests for diagnosis of bovine and human tuberculosis, mainly caused by Mycobacterium bovis and Mycobacterium tuberculosis,

  20. Mycobacterium malmesburyense sp. nov., a non-tuberculous species of the genus Mycobacterium revealed by multiple gene sequence characterization.

    Science.gov (United States)

    Gcebe, Nomakorinte; Rutten, Victor; Pittius, Nicolaas Gey van; Naicker, Brendon; Michel, Anita

    2017-04-01

    Non-tuberculous mycobacteria (NTM) are ubiquitous in the environment, and an increasing number of NTM species have been isolated and characterized from both humans and animals, highlighting the zoonotic potential of these bacteria. Host exposure to NTM may impact on cross-reactive immune responsiveness, which may affect diagnosis of bovine tuberculosis and may also play a role in the variability of the efficacy of Mycobacterium bovis BCG vaccination against tuberculosis. In this study we characterized 10 NTM isolates originating from water, soil, nasal swabs of cattle and African buffalo as well as bovine tissue samples. These isolates were previously identified during an NTM survey and were all found, using 16S rRNA gene sequence analysis to be closely related to Mycobacterium moriokaense. A polyphasic approach that included phenotypic characterization, antibiotic susceptibility profiling, mycolic acid profiling and phylogenetic analysis of four gene loci, 16S rRNA, hsp65, sodA and rpoB, was employed to characterize these isolates. Sequence data analysis of the four gene loci revealed that these isolates belong to a unique species of the genus Mycobacterium. This evidence was further supported by several differences in phenotypic characteristics between the isolates and the closely related species. We propose the name Mycobacterium malmesburyense sp. nov. for this novel species. The type strain is WCM 7299T (=ATCC BAA-2759T=CIP 110822T).

  1. Mycobacterium angelicum sp. nov., a non-chromogenic, slow-growing species isolated from fish and related to Mycobacterium szulgai.

    Science.gov (United States)

    Pourahmad, Fazel; Pate, Mateja; Ocepek, Matjaž; Borroni, Emanuele; Cabibbe, Andrea M; Capitolo, Eleonora; Cittaro, Davide; Frizzera, Eliana; Jenčič, Vlasta; Mariottini, Alessandro; Marumo, Kenji; Vaggelli, Guendalina; Cirillo, Daniela M; Tortoli, Enrico

    2015-12-01

    The name 'Mycobacterium angelicum' dates back to 2003 when it was suggested for a slowly growing mycobacterium isolated from freshwater angelfish. This name is revived here and the novel species is proposed on the basis of the polyphasic characterization of four strains including the original one. The four strains presented 100 % 16S rRNA gene sequence similarity with Mycobacterium szulgai but clearly differed from M. szulgai for the milky white aspect of the colonies. The sequence similarity with the type strain of M. szulgai ranged, in eight additionally investigated genetic targets, from 78.9 to 94.3 %, an evident contrast with the close relatedness that emerged at the level of 16S rRNA gene. The average nucleotide identity between the genomes of M. szulgai DSM 44166T and strain 126/5/03T (type strain of the novel species) was 92.92 %, and supported the status of independent species. The confirmation of the name Mycobacterium angelicum sp. nov. is proposed, with strain 126/5/03T ( = CIP 109313T = DSM 45057T) as the type strain.

  2. Line probe assay for differentiation within Mycobacterium tuberculosis complex. Evaluation on clinical specimens and isolates including Mycobacterium pinnipedii

    DEFF Research Database (Denmark)

    Kjeldsen, Marianne Kirstine; Bek, Dorte; Rasmussen, Erik Michael

    2009-01-01

    A line probe assay (GenoType MTBC) was evaluated for species differentiation within the Mycobacterium tuberculosis complex (MTBC). We included 387 MTBC isolates, 43 IS6110 low-copy MTBC isolates, 28 clinical specimens with varying microscopy grade, and 30 isolates of non-tuberculous mycobacteria...

  3. Etude de l'effet du stress salin (NaCl) chez deux variétés de tomate ...

    African Journals Online (AJOL)

    La germination, les paramètres de croissance ainsi que les paramètres biochimiques, sont comparés chez deux variétés de tomate (Campbell 33 et Mongal) soumises à des concentrations croissantes de NaCl. (0,17, 50, 85 et 130 mM). Le pourcentage de germination des graines diminue avec l'augmentation de la salinité ...

  4. Activité antérieure – Le chômage chez les jeunes, un problème d ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    7 juil. 2016 ... Gordon Betcherman, professeur à l'École de développement international et mondialisation de l'Université d'Ottawa et coauteur du Rapport sur le développement dans le monde 2013 : Emplois publié par la Banque mondiale, a évoqué la nécessité d'enrichir les connaissances au sujet du chômage chez ...

  5. Apport des approches inspirées de la neuropsychologie au diagnostic d'autisme chez l'adulte: une étude de cas

    OpenAIRE

    Weiner , L.; Baratta , A.; Henry , J.; Di Santi , C.

    2010-01-01

    Resume Nous allons illustrer a partir d?un cas clinique les procedures diagnostiques des troubles du spectre autistique chez l?adulte, inspirees des theories neurocognitives actuelles. Nous relatons le cas d?un homme de 29 ans recu en consultation psychiatrique. Le diagnostic initialement retenu etait celui de personnalite evitante, compliquee de phobie sociale et d?un trouble depressif intercurrent. Malgre la diminution des symptomes anxieux et depressifs apres l?instauration d?un...

  6. Feline leprosy due to Mycobacterium lepraemurium.

    Science.gov (United States)

    O'Brien, Carolyn R; Malik, Richard; Globan, Maria; Reppas, George; McCowan, Christina; Fyfe, Janet A

    2017-07-01

    This paper, the second in a series of three on 'feline leprosy', provides a detailed description of disease referable to Mycobacterium lepraemurium, the most common cause of feline leprosy worldwide. Cases were sourced retrospectively and prospectively for this observational study, describing clinical, geographical and molecular microbiological data for cats definitively diagnosed with M lepraemurium infection. A total of 145 cases of feline leprosy were scrutinised; 114 'new' cases were sourced from the Victorian Infectious Diseases Reference Laboratory records, veterinary pathology laboratories or veterinarians, and 31 cases were derived from six published studies. Sixty-five cats were definitively diagnosed with M lepraemurium infection. Typically, cats were 1-3 years of age when first infected, with a male gender predilection. Affected cats were generally systemically well. All had outdoor access. Lesions tended to consist of one or more cutaneous/subcutaneous nodules, typically located on the head and/or forelimbs, possibly reflecting the most likely locations for a rodent bite as the site of inoculation for organisms. Nodules had the propensity to ulcerate at some stage in the clinical course. The cytological and histological picture varied from tuberculoid, with relatively low bacterial numbers, to lepromatous with moderate to high bacterial numbers. Treatment was varied, although most cats underwent surgical resection of lesions with adjunctive medical therapy, most often using a combination of oral clarithromycin and rifampicin. Prognosis for recovery was generally good, and in two cases there was spontaneous remission without the requirement for medical intervention. Untreated cats continued to enjoy an acceptable quality of life despite persistence of the disease, which extended locally but had no apparent tendency to disseminate to internal organs. M lepraemurium causes high bacterial index (lepromatous) or low bacterial index (tuberculoid) feline

  7. Iconicity and Typography in Steve McCaffery’s Panel-Poems Iconicité et typographie chez Steve McCaffery: les poèmes-panneaux

    Directory of Open Access Journals (Sweden)

    Fiona McMahon

    2007-01-01

    Full Text Available Cet article se propose de retracer les étapes d’un projet d’écriture qui se rattache historiquement aux mouvances internationales de la poésie concrète comme à l’émergence d’une poétique de l’iconicité chez l’avant-garde nord-américaine du vingtième siècle. Le matérialisme dont se réclame la poésie de Steve McCaffery se traduit dans son œuvre typographique Carnival (1967-75 par une pratique mettant en jeu la lettre, le plus petit dénominateur de la langue, et la page, qui doit se laisser transformer pour que se réalise un nouvel espace de signification poétique. Le dialogue qui se joue entre le lisible et le visible prend forme grâce à un répertoire de techniques expérimenté avec la machine à écrire et de concert avec le lecteur, devenu acteur de l’œuvre poétique. La pratique architecturale du poème-panneau chez McCaffery sera envisagée dans son rapport actuel avec le prolongement des problématiques de la poésie visuelle chez l’avant-garde nord-américaine.

  8. Revival and emended description of 'Mycobacterium paraffinicum' Davis, Chase and Raymond 1956 as Mycobacterium paraffinicum sp. nov., nom. rev.

    Science.gov (United States)

    Toney, Nadege; Adekambi, Toidi; Toney, Sean; Yakrus, Mitchell; Butler, W Ray

    2010-10-01

    The omission of the name 'Mycobacterium paraffinicum' from the Approved Lists of Bacterial Names was due to phenotypic confusion surrounding a close relationship with Mycobacterium scrofulaceum. Correspondingly, 'M. paraffinicum' strains grew slowly in > 7 days, stained acid-alcohol-fast and produced yellow-pigmented, smooth, waxy colonies in the dark at an optimal temperature of 35°C. However, 'M. paraffinicum' strains demonstrated no activity for urease, nicotinamidase or pyrazinamidase and lacked growth at 42°C, unlike M. scrofulaceum. The mycolic acid pattern, as determined by HPLC, clustered 'M. paraffinicum' with M. scrofulaceum, Mycobacterium avium and Mycobacterium parascrofulaceum. Strains were fully susceptible to linezolid, rifabutin, clarithromycin and amikacin. Examination of the historical reference strain of 'M. paraffinicum', ATCC 12670, and five additional isolates using comparative studies with 16S rRNA, hsp65 and rpoB gene and concatenated sequences showed that they formed a tight taxonomic group that was distinct from similar non-tuberculous mycobacteria. Multilocus enzyme electrophoresis (MEE) analysis confirmed a close association of the five additional isolates with the reference strain of 'M. paraffinicum' with a genetic distance of 0.12 and showed that all six strains were distinct from other closely related species. These genetic results provided unambiguous evidence of the uniqueness of this slowly growing, scotochromogenic species and supported the revival of the name as Mycobacterium paraffinicum (ex Davis, Chase and Raymond 1956) sp. nov., nom. rev. We propose the previously deposited reference strain ATCC 12670(T) =DSM 44181(T) =NCIMB 10420(T), located in collections worldwide, as the type strain.

  9. Real-Time Measurement of Host Bioenergetics During Mycobacterium Tuberculosis Infection

    Science.gov (United States)

    2015-05-01

    AWARD NUMBER: W81XWH-13-1-0149 TITLE: “Real-Time Measurement of Host Bioenergetics During Mycobacterium Tuberculosis Infection...successfully adapted metabolic flux analysis using a Seahorse XF96 metabolic flux analyzer to study Mycobacterium tuberculosis energy metabolism in an...Mycobacterium tuberculosis function. In: Systems Biology of Tuberculosis . Editors: J McFadden, D Beste and A Kierzek. 2013. Springer, New York, NY. 2

  10. Methylobacterium spp. as an indicator for the presence or absence of Mycobacterium spp.

    OpenAIRE

    Falkinham III, Joseph O.; Williams, Myra D.; Kwait, Rebecca; Lande, Leah

    2016-01-01

    Objective/Background: A published survey of bacteria in showerhead biofilm samples revealed that Methylobacterium spp. and Mycobacterium spp. seldom coexisted in biofilms. Method: To confirm that information, biofilm samples were collected from household plumbing of Mycobacterium avium patients and Methylobacterium spp. and M. avium numbers were measured by direct colony counts. Results: The results demonstrated that if Methylobacterium spp. were present, Mycobacterium spp. were absent,...

  11. Cervical Lymphadenitis by Mycobacterium triplex in an Immunocompetent Child: Case Report and Review

    OpenAIRE

    Caruso, G.; Angotti, R.; Molinaro, F.; Benicchi, E.; Cerchia, E.; Messina, M.

    2013-01-01

    Mycobacterium triplex was first described in 1996. This nontuberculous Mycobacterium causes a severe pulmonary disease in immunocompromised patients but it can involve also healthy patients. A literature search was made on the PubMed database and it produced only few cases of children with cervical lymphadenitis due to this Mycobacterium Triplex. We are describing a case of M. triplex cervical lymphadenitis in an immunocompetent child.

  12. Profil épidémiologique des pathologies respiratoires chez l’enfant à l’Hôpital d’Enfants de Rabat, Maroc

    Science.gov (United States)

    Benchekroun, Ilham; Boubkraoui, Mohamed El Mahdi; Mekaoui, Nour; Karboubi, Lamia; Mahraoui, Chafiq; Dakhama, Badr Sououd Benjelloun

    2017-01-01

    Introduction Les pathologies respiratoires représentent un motif fréquent d'hospitalisation en pédiatrie. L'objectif de cette étude était d'évaluer le profil épidémiologique des pathologies respiratoires chez l'enfant à l'hôpital d'enfants de Rabat, Maroc. Méthodes Il s'agit d'une étude observationnelle transversale qui a concerné tous les cas d'enfants âgés de 3 mois à 15 ans hospitalisés pour une pathologie respiratoire au service de pneumoallergologie et infectiologie pédiatriques de l'hôpital d'enfants de Rabat sur une période d'une année, du 1 janvier 2014 au 31 décembre 2014. Résultats Sur 3537 patients hospitalisés, 2493 (70,5%) l'ont été pour une pathologie respiratoire. Les hospitalisations pour exacerbation d'asthme (p < 0,001), bronchiolite aigüe (p < 0,001) et dyspnée laryngée (p = 0,004) étaient plus fréquentes chez le garçon alors que les hospitalisations pour pneumopathie aigüe (p = 0,005), pour inhalation de corps étranger (p = 0,007) et pour coqueluche (p = 0,020) étaient plus fréquentes chez la fille. Les hospitalisations pour pneumopathie aigüe (p < 0,001), exacerbation de séquelles graves de virose (p < 0,001) et pour coqueluche (p < 0,001) étaient plus fréquentes chez le nourrisson. Les hospitalisations pour pneumopathie aigüe (p < 0,001) et pour coqueluche (p = 0,015) étaient plus fréquentes en période automnohivernale. Conclusion Les motifs d'hospitalisation étaient dominés par les exacerbations d'asthme et la bronchiolite aigüe, lesquelles étaient plus fréquentes chez le garçon. Les infections respiratoires, représentées par les pneumopathies aigües et la coqueluche, étaient plus fréquentes en période automnohivernale et touchaient plus le nourrisson. PMID:29675122

  13. Disseminated Infection by Mycobacterium sherrisii and Histoplasma capsulatum in an African HIV-Infected Patient

    Science.gov (United States)

    Taján, Juan; Espasa, Mateu; Sala, Montserrat; Navarro, Marta; Font, Bernat; González-Martín, Julián; Segura, Ferran

    2013-01-01

    Mycobacterium sherrisii is a new species of opportunistic, slow-growing, non-tuberculous Mycobacterium closely related to Mycobacterium simiae that can currently be identified with the sequence of 16S rARN gene and the heat-shock protein 65. Few cases of patients infected by this Mycobacterium have been reported and all of them were associated with human immunodeficiency virus or other immunosuppressive conditions. Clinical management is complex, because there is not a clear correlation between the in vitro antibiotic susceptibility testing and the patient's clinical outcome. PMID:23419367

  14. Activity of Scottish plant, lichen and fungal endophyte extracts against Mycobacterium aurum and Mycobacterium tuberculosis.

    Science.gov (United States)

    Gordien, Andréa Y; Gray, Alexander I; Ingleby, Kevin; Franzblau, Scott G; Seidel, Véronique

    2010-05-01

    With tuberculosis the leading bacterial killer worldwide and other mycobacterial diseases on the increase, the search for new antimycobacterial agents is timely. In this study, extracts from plants, lichens and fungal endophytes of Scottish provenance were screened for activity against Mycobacterium aurum and M. tuberculosis H(37)Rv. The best activity against M. aurum was observed for extracts of Juniperus communis roots and Cladonia arbuscula (MIC = 4 microg/mL), and a fungal endophyte isolated from Vaccinium myrtillus (MIC = 8 microg/mL). The best activity against M. tuberculosis was observed for extracts of C. arbuscula, Empetrum nigrum, J. communis roots, Calluna vulgaris aerial parts, Myrica gale roots and stems (93 to 99% inhibition at 100 microg/mL). Potent antitubercular activity (90 to 96% inhibition at 100 microg/mL) was also observed for the ethanol extracts of Xerocomus badius, Chalciporus piperatus, Suillus luteus and of endophytes isolated from C. vulgaris, E. nigrum, Vaccinium vitis-idaea and V. myrtillus. The results obtained this study provide, in part, some scientific basis for the traditional use of some of the selected plants in the treatment of tuberculosis. They also indicate that fungal endophytes recovered from Scottish plants are a source of antimycobacterial agents worthy of further investigation. Copyright (c) 2009 John Wiley & Sons, Ltd.

  15. Mycobacterium fortuitum and Mycobacterium chelonae biofilm formation under high and low nutrient conditions.

    Science.gov (United States)

    Hall-Stoodley, L; Keevil, C W; Lappin-Scott, H M

    1998-12-01

    The rapidly growing mycobacteria (RGM) are broadly disbursed in the environment. They have been recovered from freshwater, seawater, wastewater and even potable water samples and are increasingly associated with non-tuberculous mycobacterial disease. There is scant evidence that non-tuberculous mycobacteria (NTM) and RGM form biofilms. Therefore, an experimental system was designed to assess the ability of RGM to form biofilms under controlled laboratory conditions. A flat plate reactor flow cell was attached to either a high or low nutrient reservoir and monitored by image analysis over time. Two surfaces were chosen for assessment of biofilm growth: silastic which is commonly used in medical settings and high density polyethylene (HDPE) which is prevalent in water distribution systems. The results show that Mycobacterium fortuitum and M. chelonae formed biofilms under both high and low nutrient conditions on both surfaces studied. These results suggest that RGM may form biofilms under a variety of conditions in industrial and medical environments. 1998 Society of Applied Microbiology.

  16. The Complete Structure of the Mycobacterium smegmatis 70S Ribosome

    Directory of Open Access Journals (Sweden)

    Jendrik Hentschel

    2017-07-01

    Full Text Available The ribosome carries out the synthesis of proteins in every living cell. It consequently represents a frontline target in anti-microbial therapy. Tuberculosis ranks among the leading causes of death worldwide, due in large part to the combination of difficult-to-treat latency and antibiotic resistance. Here, we present the 3.3-Å cryo-EM structure of the 70S ribosome of Mycobacterium smegmatis, a close relative to the human pathogen Mycobacterium tuberculosis. The structure reveals two additional ribosomal proteins and localizes them to the vicinity of drug-target sites in both the catalytic center and the decoding site of the ribosome. Furthermore, we visualized actinobacterium-specific rRNA and protein expansions that extensively remodel the ribosomal surface with implications for polysome organization. Our results provide a foundation for understanding the idiosyncrasies of mycobacterial translation and reveal atomic details of the structure that will facilitate the design of anti-tubercular therapeutics.

  17. Mycobacterium tuberculosis Complex Members Adapted to Wild and Domestic Animals.

    Science.gov (United States)

    Malone, Kerri M; Gordon, Stephen V

    2017-01-01

    The Mycobacterium tuberculosis complex (MTBC) is composed of several highly genetically related species that can be broadly classified into those that are human-host adapted and those that possess the ability to propagate and transmit in a variety of wild and domesticated animals. Since the initial description of the bovine tubercle bacillus, now known as Mycobacterium bovis, by Theobald Smith in the late 1800's, isolates originating from a wide range of animal hosts have been identified and characterized as M. microti, M. pinnipedii, the Dassie bacillus, M. mungi, M. caprae, M. orygis and M. suricattae. This chapter outlines the events resulting in the identification of each of these animal-adapted species, their close genetic relationships, and how genome-based phylogenetic analyses of species-specific variation amongst MTBC members is beginning to unravel the events that resulted in the evolution of the MTBC and the observed host tropism between the human- and animal-adapted member species.

  18. Adhesion of Mycobacterium smegmatis to Charged Surfaces and Diagnostics Implications

    Science.gov (United States)

    Gorse, Diane; Dhinojwala, Ali; Moore, Francisco

    Pulmonary tuberculosis (PTB) causes more than 1 million deaths annually. Smear microscopy is a primary rapid detection tool in areas where 95 % of PTB cases occur. This technique, in which the sputum of a symptomatic patient is stained and examined using a light microscope for Mycobacterium tuberculosis (MTB) shows sensitivity between 20 and 60 %. Insufficient bacterial isolation during sample preparation may be a reason for low sensitivity. We are optimizing a system to capture bacteria on the basis of electrostatic interactions to more thoroughly isolate bacteria from suspension and facilitate more accurate detection. Silica supports coated with positively-charged polyelectrolyte, poly(diallyldimethylammonium chloride), captured approximately 4.1 times more Mycobacterium smegmatis, a model organism for MTB, than was captured on negatively-charged silica substrates. Future experimentation will employ branched polymer systems and seek to justify the use of colloidal stability theories to describe initial capture. Supported by University of Akron, Department of Polymer Science, Department of Biology; LORD Corporation.

  19. Intraocular manifestations of mycobacterium tuberculosis: A review of the literature

    Directory of Open Access Journals (Sweden)

    Lauren A. Dalvin

    2017-05-01

    Full Text Available Mycobacterium tuberculosis: is most commonly associated with pulmonary infection. However, tuberculosis (TB can also affect the eye. TB can affect nearly any tissue in the eye, and a high index of suspicion is required for accurate diagnosis, as many of the intraocular manifestations of TB can mimic other, more common diseases. Correct diagnosis is critical because systemic anti-tuberculosis treatment may be required, and vision loss or even loss of the affected eye can occur without proper treatment. Thus, it is important for ophthalmologists and infectious disease specialists to work together to accurately diagnose and treat intraocular TB. This article reports the various known presentations of intraocular TB and reviews important elements of diagnosis and treatment. Keywords: Mycobacterium, Tuberculosis, Choroidal granuloma, Retinal vasculitis

  20. Siderocalin inhibits the intracellular replication of Mycobacterium tuberculosis in macrophages

    DEFF Research Database (Denmark)

    Johnson, Erin E; Srikanth, Chittur V; Sandgren, Andreas

    2010-01-01

    Siderocalin is a secreted protein that binds to siderophores to prevent bacterial iron acquisition. While it has been shown to inhibit the growth of Mycobacterium tuberculosis (M.tb) in extracellular cultures, its effect on this pathogen within macrophages is not clear. Here, we show that sideroc......Siderocalin is a secreted protein that binds to siderophores to prevent bacterial iron acquisition. While it has been shown to inhibit the growth of Mycobacterium tuberculosis (M.tb) in extracellular cultures, its effect on this pathogen within macrophages is not clear. Here, we show...... findings are consistent with an important role for siderocalin in protection against M.tb infection and suggest that exogenously administered siderocalin may have therapeutic applications in tuberculosis....

  1. Diversity and evolution of drug resistance mechanisms in Mycobacterium tuberculosis

    Directory of Open Access Journals (Sweden)

    Al-Saeedi M

    2017-10-01

    Full Text Available Mashael Al-Saeedi, Sahal Al-Hajoj Department of Infection and Immunity, Mycobacteriology Research Section, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia Abstract: Despite the efficacy of antibiotics to protect humankind against many deadly pathogens, such as Mycobacterium tuberculosis, nothing can prevent the emergence of drug-resistant strains. Several mechanisms facilitate drug resistance in M. tuberculosis including compensatory evolution, epistasis, clonal interference, cell wall integrity, efflux pumps, and target mimicry. In this study, we present recent findings relevant to these mechanisms, which can enable the discovery of new drug targets and subsequent development of novel drugs for treatment of drug-resistant M. tuberculosis. Keywords: Mycobacterium tuberculosis, antibiotic resistance, compensatory evolution, epistasis, efflux pumps, fitness cost

  2. Isolation of Mycobacterium paratuberculosis from Milk by Immunomagnetic Separation

    OpenAIRE

    Grant, Irene R.; Ball, Hywel J.; Rowe, Michael T.

    1998-01-01

    An immunomagnetic separation (IMS) technique was developed to facilitate selective isolation of Mycobacterium paratuberculosis cells from milk. Rabbit polyclonal antibodies against radiation-killed intact M. paratuberculosis cells were produced and used to coat sheep anti-rabbit immunoglobulin G (IgG) type M-280 Dynabeads. The rabbit anti-M. paratuberculosis IgG-coated beads (IMB) reacted strongly with laboratory strains of M. paratuberculosis as determined by slide agglutination, and microsc...

  3. Cutaneous Mycobacterium abscessus Infection Associated with Mesotherapy Injection.

    Science.gov (United States)

    Wongkitisophon, Pranee; Rattanakaemakorn, Ploysyne; Tanrattanakorn, Somsak; Vachiramon, Vasanop

    2011-02-18

    Non-tuberculous mycobacterial skin infections have an increasing incidence. In immunocompetent patients, they usually follow local trauma. We present a case of cutaneous Mycobacterium abscessus infection following mesotherapy. The lesions were successfully treated with a combination of clarithromycin, ciprofloxacin, and doxycycline. Atypical mycobacterial infection should be suspected in patients who develop late-onset skin and soft tissue infection after cutaneous injury, injection, and surgical intervention, particularly if they do not respond to conventional antibiotic treatment.

  4. Cutaneous Mycobacterium abscessus Infection Associated with Mesotherapy Injection

    Directory of Open Access Journals (Sweden)

    Pranee Wongkitisophon

    2011-02-01

    Full Text Available Non-tuberculous mycobacterial skin infections have an increasing incidence. In immunocompetent patients, they usually follow local trauma. We present a case of cutaneous Mycobacterium abscessus infection following mesotherapy. The lesions were successfully treated with a combination of clarithromycin, ciprofloxacin, and doxycycline. Atypical mycobacterial infection should be suspected in patients who develop late-onset skin and soft tissue infection after cutaneous injury, injection, and surgical intervention, particularly if they do not respond to conventional antibiotic treatment.

  5. Bloodstream Infections with Mycobacterium tuberculosis among HIV patients

    Centers for Disease Control (CDC) Podcasts

    2010-09-23

    This podcast looks at bloodstream infections with Mycobacterium tuberculosis and other pathogens among outpatients infected with HIV in Southeast Asia. CDC health scientist Kimberly McCarthy discusses the study and why bloodstream infections occur in HIV-infected populations.  Created: 9/23/2010 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 9/23/2010.

  6. Mycobacterium avium-intracellulare: a rare cause of subacromial bursitis.

    Science.gov (United States)

    Sinha, Raj; Tuckett, John; Hide, Geoff; Dildey, Petra; Karsandas, Alvin

    2015-01-01

    Septic subacromial bursitis is an uncommon disorder with only a few reported cases in the literature. The most common causative organism is Staphylococcus aureus. We report the case of a 61-year-old female with a septic subacromial bursitis where the causative organism was found to be Mycobacterium avium-intracellulare (MAI). The diagnosis was only made following a biopsy, and we use this case to highlight the importance of recognising the need to consider a biopsy and aspiration in atypical situations.

  7. Structural and Functional Studies of Phosphoenolpyruvate Carboxykinase from Mycobacterium tuberculosis

    Czech Academy of Sciences Publication Activity Database

    Machová, Iva; Snášel, Jan; Dostál, Jiří; Brynda, Jiří; Fanfrlík, Jindřich; Singh, M.; Tarábek, Ján; Vaněk, O.; Bednárová, Lucie; Pichová, Iva

    2015-01-01

    Roč. 10, č. 3 (2015), e0120682/1-e0120682/21 E-ISSN 1932-6203 R&D Projects: GA MŠk LO1302 EU Projects: European Commission(XE) 241587 - SYSTEMTB Institutional support: RVO:61388963 Keywords : crystal structure * noncovalent complexes * Mycobacterium tuberculosis * mechanism Subject RIV: CE - Biochemistry Impact factor: 3.057, year: 2015 http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0120682

  8. Studium role fosfofruktokinasy A a B v metabolismu Mycobacterium tuberculosis

    Czech Academy of Sciences Publication Activity Database

    Machová, Iva; Snášel, Jan; Pichová, Iva

    2014-01-01

    Roč. 108, č. 5 (2014), s. 542 ISSN 0009-2770. [Mezioborové setkání mladých biologů, biochemiků a chemiků /14./. 13.05.2014-16.05.2014, Milovy] Grant - others:European Research Council(XE) FP7-245187 Institutional support: RVO:61388963 Keywords : Mycobacterium tuberculosis * phosphofructokinase Subject RIV: CE - Biochemistry

  9. Tumor necrosis factor blockers influence macrophage responses to Mycobacterium tuberculosis

    OpenAIRE

    HARRIS, JAMES; HARRIS, JAMES

    2008-01-01

    PUBLISHED umor necrosis factor (TNF)?? is a proinflammatory cytokine that mediates inflammation in response to various pathogens, including Mycobacterium tuberculosis, but is also a key factor in the pathogenesis of rheumatoid arthritis and other autoimmune diseases. Three TNF???suppressing drugs have been approved to treat selected autoimmune diseases; 2 are monoclonal antibodies against TNF?? (adalimumab and infliximab), and the other is a soluble TNF receptor/Fc fusion protein (etanerce...

  10. Disseminated Mycobacterium abscessus infection in a peritoneal dialysis patient

    Directory of Open Access Journals (Sweden)

    Vincent H.J.F. Mooren

    2017-01-01

    Full Text Available A disseminated peritoneal dialysis-related Mycobacterium abscessus infection is very rare. M. abscessus belongs to the rapidly growing mycobacteria and can be misidentified as a diphtheroid bacterium, which in our case delayed diagnosis and optimal treatment. Due to intrinsic resistance to most antimicrobials, therapeutic options in M. abscessus infections are limited. Infection often leads to catheter loss. A fatal outcome, like in our case, is not exceptional.

  11. Mycobacterium bovis in milk samples: a preliminary investigation using PCR

    International Nuclear Information System (INIS)

    Achel, D.G.; Gyamfi, O.K.; Broni, F.; Gomda, Y.; Brown, C.A.

    2007-01-01

    PCR was used to screen milk samples (n=41) for Mycobacterium bovis. DNA samples were obtained through concentration by 50% sucrose addition and centrifugation. Sixteen (16) samples (or 39%) were positive for M. Bovis DNA and the rest 25 (or 61%) were negative. All four kraals had some samples testing positive for M. bovis; the highest being 50% (5/10) and the lowest being 13% (2/15). (au)

  12. Triple valve endocarditis by mycobacterium tuberculosis. A case report

    Directory of Open Access Journals (Sweden)

    Shaikh Quratulain

    2012-09-01

    Full Text Available Abstract Background Granulomas caused by Mycobacterium Tuberculosis have been observed at autopsy in the heart, pre-dominantly in the myocardium and endocardium, but rarely involving the coronary vessels and valvular structures. Mycobacterium tuberculosis valvular endocarditis is extremely rare, with most reports coming from autopsy series. Case presentation We report the case of a 17 year old immunocompetent girl who presented with history of fever, malaise, foot gangrene and a left sided hemiparesis. On investigation she was found to have infective endocarditis involving the aortic, mitral and tricuspid valves. She had developed a right middle cerebral artery stroke. She underwent dual valve replacement and tricuspid repair. The vegetations showed granulomatous inflammation but blood cultures and other biological specimen cultures were negative for any organisms. She was started on antituberculous treatment and anticoagulation. Conclusion This is the first reported case of triple valve endocarditis by Mycobacterium Tuberculosis in an immunocompetent host. Especially important is the fact that the right heart is involved which has been historically described in the setting of intravenous drug abuse. This implies that Tuberculosis should be considered in cases of culture negative endocarditis in endemic areas like Pakistan even in immunocompetent hosts.

  13. Infection due to Mycobacterium bovis in common variable immunodeficiency

    Directory of Open Access Journals (Sweden)

    Diana Andrea Herrera-Sánchez

    2015-02-01

    Full Text Available Common variable immunodeficiency (CVID is an heterogeneous group of disorders characterized by impaired antibody production. It shows a wide spectrum of manifestations including severe and recurrent respiratory infections (Streptococcus pneumoniae, Haemophilus and gastrointestinal (Campylobacter jejuni, rotavirus and Giardia lamblia. Viral infections caused by herpes zoster, cytomegalovirus (CMV and hepatitis C are rare. The opportunistic agents such as CMV, Pneumocystis jirovecii, cryptococcus and atypical mycobacteria have been reported as isolated cases. This paper reports the case of a 38-year-old female patient, who began six years before with weight loss of 7 kg in six months, fatigue, weakness, sweating, fever and abdominal pain. Furthermore, patient had intestinal obstruction and abdominal CT showed mesenteric lymph growth. The mesenteric lymph node biopsy revealed positives Mycobacterium PCR, Ziehl-Neelsen staining and culture for M. bovis. In the laparotomy postoperative period was complicated with nosocomial pneumonia, requiring mechanical ventilation and tracheostomy. Two years later, she developed right renal abscess that required surgical drainage, once again with a positive culture for Mycobacterium bovis. She was referred to highly specialized hospital and we documented panhypogammaglobulinemia and lymphopenia. Secondary causes of hypogammaglobulinemia were ruled out and common variable immunodeficiency (CVID was confirmed, we started IVIG replacement. Four years later she developed mixed cellularity Hodgkin’s lymphoma. Until today she continues with IVIG and chemotherapy. This report of a patient with CVID and Mycobacterium bovis infection, a unusual association, shows the cellular immunity susceptibility in this immunodeficiency, additional to the humoral defect.

  14. Mycobacterium stephanolepidis sp. nov., a rapidly growing species related to Mycobacterium chelonae, isolated from marine teleost fish, Stephanolepis cirrhifer.

    Science.gov (United States)

    Fukano, Hanako; Wada, Shinpei; Kurata, Osamu; Katayama, Kinya; Fujiwara, Nagatoshi; Hoshino, Yoshihiko

    2017-08-01

    A previously undescribed rapidly growing, non-pigmented mycobacterium was identified based on biochemical and nucleic acid analyses, as well as growth characteristics. Seven isolates were cultured from samples collected from five thread-sail filefish (Stephanolepis cirrhifer) and two farmed black scraper (Thamnaconus modestus). Bacterial growth occurred at 15-35 °C on Middlebrook 7H11 agar. The bacteria were positive for catalase activity at 68 °C and urease activity, intermediate for iron uptake, and negative for Tween 80 hydrolysis, nitrate reduction, semi-quantitative catalase activity and arylsulfatase activity at day 3. No growth was observed on Middlebrook 7H11 agar supplemented with picric acid, and very little growth was observed in the presence of 5 % NaCl. α- and α'-mycolates were identified in the cell walls, and a unique profile of the fatty acid methyl esters and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) profiles of the protein and cell-wall lipids were acquired. Sequence analysis revealed that the seven isolates shared identical sequences for the 16S rRNA, rpoB, hsp65, recA and sodA genes. Phylogenetic analysis of the five gene sequences confirmed that the isolates were unique, but closely related to Mycobacterium chelonae. Antibiotic susceptibility testing revealed the minimum inhibitory concentration (MIC) of clarithromycin against this novel species was Mycobacterium salmoniphilum. The hsp65 PCR restriction enzyme analysis pattern differed from those of M. chelonae and M. salmoniphilum. Based on these findings, the name Mycobacterium stephanolepidis sp. nov. is proposed for this novel species, with the type strain being NJB0901 T (=JCM 31611 T =KCTC 39843 T ).

  15. Bases mécanistiques des effets d'un insecticide agrovétérinaire, le fipronil,et/ou de ses métabolites sur la fonction thyroîdienne chez le rat

    OpenAIRE

    Roques, Béatrice

    2012-01-01

    Le fipronil, insecticide largement utilisé, est un perturbateur thyroïdien chez le rat modulant le catabolisme hépatique des hormones thyroïdiennes. Ses effets chez le mouton, considéré comme un modèle plus pertinent que le rat pour étudier une régulation de la fonction thyroïdienne chez l'Homme, sont plus limités. Le but de cette thèse était de caractériser au niveau hépatique le mode d'action du fipronil sur la fonction thyroïdienne en s'intéressant 1) au rôle potentiel du principal métabol...

  16. Cerebral Scintigraphy in the Child and Nursing Infant; La Scintigraphie Cerebrale chez l'Enfant et le Nourrisson

    Energy Technology Data Exchange (ETDEWEB)

    Akerman, M.; Rougerie, J.; Guiot, G. [INSERM, Hopital Foch, Suresnes (France)

    1969-05-15

    overall results of cerebral scintigraphy are less favourable in the case of cerebral tumours in children than in that of adults. The reason for this is the high frequency in children of tumours of the brain stem, the pituitary and the third ventricle, the detectability of which is low. However, very good results were obtained in the case of 35 tumours of the cerebellum and the fourth ventricle as a result of using very rigorous techniques. Excellent results have also been obtained with other surgical lesions, such as chronic subdural haematoma in the nursing infant and vascular malformations. In conditions not amenable to neurosurgery definitely false results were the exception. Lastly, the authors present the initial results of a study of the cerebral cisterns and ventricles. They emphasize the abundance of information supplied by these scintigraphic methods and their great utility for the neurosurgeon. (author) [French] La scintigraphie cerebrale chez l' enfant a fait l'objet de peu de travaux publies. Une etude separee chez l' enfant se justifie cependant par les particularites de la pathologie neurochirurgicale infantile. L' exploration de l' enfant et du nourrisson conduit a discuter les donnees dosimetriques et a poser le probleme de la detectabilite des tumeurs de la fosse posterieure, des tumeurs medianes de la base du crane, et des astrocytomes, qui sont justement les tumeurs les plus frequentes en pathologie infantile. Enfin, l' enfant et le nourrisson sont les sujets d'application privilegies des techniques de scintigraphie apres injection locale de composes radioactifs, par voie sous- arachno'idienne, intra-ventriculaire, ou intra-cavitaire, pour 1' etude des hydrocephalies communicantes ou par stenose, des malformations meningo-encephaliques et des hematomes sous-duraux chroniques. En cinq ans ont ete explores 400 enfants et nourrissons ages de 2 mois a 16 ans, soit 10% des 4000 explorations craniennes effectuees dans le laboratoire des auteurs. Parmi ces

  17. Systeme microfluidique d'analyse sanguine en temps reel pour l'imagerie moleculaire chez le petit animal

    Science.gov (United States)

    Convert, Laurence

    De nouveaux radiotraceurs sont continuellement développés pour améliorer l'efficacité diagnostique en imagerie moléculaire, principalement en tomographie d'émission par positrons (TEP) et en tomographie d'émission monophotonique (TEM) dans les domaines de l'oncologie, de la cardiologie et de la neurologie. Avant de pouvoir être utilisés chez les humains, ces radiotraceurs doivent être caractérisés chez les petits animaux, principalement les rats et les souris. Pour cela, de nombreux échantillons sanguins doivent être prélevés et analysés (mesure de radioactivité, séparation de plasma, séparation d'espèces chimiques), ce qui représente un défi majeur chez les rongeurs à cause de leur très faible volume sanguin (˜1,4 ml pour une souris). Des solutions fournissant une analyse partielle sont présentées dans la littérature, mais aucune ne permet d'effectuer toutes les opérations dans un même système. Les présents travaux de recherche s'insèrent dans le contexte global d'un projet visant à développer un système microfluidique d'analyse sanguine complète en temps réel pour la caractérisation des nouveaux radiotraceurs TEP et TEM. Un cahier des charges a tout d'abord été établi et a permis de fixer des critères quantitatifs et qualitatifs à respecter pour chacune des fonctions de la puce. La fonction de détection microfluidique a ensuite été développée. Un état de l'art des travaux ayant déjà combiné la microfluidique et la détection de radioactivité a permis de souligner qu'aucune solution existante ne répondait aux critères du projet. Parmi les différentes technologies disponibles, des microcanaux en résine KMPR fabriqués sur des détecteurs semiconducteurs de type p-i-n ont été identifiés comme une solution technologique pour le projet. Des détecteurs p-i-n ont ensuite été fabriqués en utilisant un procédé standard. Les performances encourageantes obtenues ont mené à initier un projet de ma

  18. Protective and therapeutic efficacy of Mycobacterium smegmatis expressing HBHA-hIL12 fusion protein against Mycobacterium tuberculosis in mice.

    Directory of Open Access Journals (Sweden)

    Shanmin Zhao

    Full Text Available Tuberculosis (TB remains a major worldwide health problem. The only vaccine against TB, Mycobacterium bovis Bacille Calmette-Guerin (BCG, has demonstrated relatively low efficacy and does not provide satisfactory protection against the disease. More efficient vaccines and improved therapies are urgently needed to decrease the worldwide spread and burden of TB, and use of a viable, metabolizing mycobacteria vaccine may be a promising strategy against the disease. Here, we constructed a recombinant Mycobacterium smegmatis (rMS strain expressing a fusion protein of heparin-binding hemagglutinin (HBHA and human interleukin 12 (hIL-12. Immune responses induced by the rMS in mice and protection against Mycobacterium tuberculosis (MTB were investigated. Administration of this novel rMS enhanced Th1-type cellular responses (IFN-γ and IL-2 in mice and reduced bacterial burden in lungs as well as that achieved by BCG vaccination. Meanwhile, the bacteria load in M. tuberculosis infected mice treated with the rMS vaccine also was significantly reduced. In conclusion, the rMS strain expressing the HBHA and human IL-12 fusion protein enhanced immunogencity by improving the Th1-type response against TB, and the protective effect was equivalent to that of the conventional BCG vaccine in mice. Furthermore, it could decrease bacterial load and alleviate histopathological damage in lungs of M. tuberculosis infected mice.

  19. Mycobacterium alsiense, a novel, slowly growing species isolated from two patients with pulmonary disease

    DEFF Research Database (Denmark)

    Richter, Elvira; Tortoli, Enrico; Fischer, Arno

    2007-01-01

    A previously undescribed, slowly growing Mycobacterium species was isolated from pulmonary specimens of two patients, one from Denmark and one from Italy. The isolates showed unique 16S rRNA internal transcribed spacers and hsp65 sequences: the 16S rRNA was most closely related to Mycobacterium...

  20. Comparative genomics of archived pyrazinamide resistant Mycobacterium tuberculosis complex isolates from Uganda

    Science.gov (United States)

    Bovine tuberculosis is a ‘neglected zoonosis’ and its contribution to the proportion of Mycobacterium tuberculosis complex infections in humans is unknown. A retrospective study on archived Mycobacterium tuberculosis complex (MTC) isolates from a reference laboratory in Uganda was undertaken to iden...

  1. Pott's disease: a case of Mycobacterium xenopi infection of the spine

    Directory of Open Access Journals (Sweden)

    Majd Alfreijat

    2013-01-01

    Full Text Available Pott's disease is an infection of the spine with Mycobacterium tuberculosis that causes destruction of the spine elements resulting in progressive kyphosis. We are describing a rare case of Pott's disease where Mycobacterium xenopi was the inculpated organism.

  2. Diffuse Lepromatous Leprosy Due to Mycobacterium lepromatosis in Quintana Roo, Mexico.

    Science.gov (United States)

    Han, Xiang Y; Quintanilla, Marco

    2015-11-01

    A 43-year-old woman of Mayan origin from Quintana Roo, Mexico, was diagnosed with diffuse lepromatous leprosy. The etiologic bacillus was determined to be Mycobacterium lepromatosis instead of Mycobacterium leprae. This case likely represents the first report of this leprosy form and its agent in the southeastern tip of Mexico. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  3. Environmental Mycobacterium avium subsp. paratuberculosis hosted by free-living amoebae

    Science.gov (United States)

    Mycobacterium avium subsp. paratuberculosis is responsible for paratuberculosis in animals. This disease, leading to an inflammation of the gastrointestinal tract, has a high impact on animal health and an important economic burden. The environmental life cycle of Mycobacterium avium subsp. paratube...

  4. Performance Assessment of the CapitalBio Mycobacterium Identification Array System for Identification of Mycobacteria

    Science.gov (United States)

    Liu, Jingbo; Yan, Zihe; Han, Min; Han, Zhijun; Jin, Lingjie; Zhao, Yanlin

    2012-01-01

    The CapitalBio Mycobacterium identification microarray system is a rapid system for the detection of Mycobacterium tuberculosis. The performance of this system was assessed with 24 reference strains, 486 Mycobacterium tuberculosis clinical isolates, and 40 clinical samples and then compared to the “gold standard” of DNA sequencing. The CapitalBio Mycobacterium identification microarray system showed highly concordant identification results of 100% and 98.4% for Mycobacterium tuberculosis complex (MTC) and nontuberculous mycobacteria (NTM), respectively. The sensitivity and specificity of the CapitalBio Mycobacterium identification array for identification of Mycobacterium tuberculosis isolates were 99.6% and 100%, respectively, for direct detection and identification of clinical samples, and the overall sensitivity was 52.5%. It was 100% for sputum, 16.7% for pleural fluid, and 10% for bronchoalveolar lavage fluid, respectively. The total assay was completed in 6 h, including DNA extraction, PCR, and hybridization. The results of this study confirm the utility of this system for the rapid identification of mycobacteria and suggest that the CapitalBio Mycobacterium identification array is a molecular diagnostic technique with high sensitivity and specificity that has the capacity to quickly identify most mycobacteria. PMID:22090408

  5. Characterization of Three Mycobacterium spp. with Potential Use in Bioremediation by Genome Sequencing and Comparative Genomics.

    Science.gov (United States)

    Das, Sarbashis; Pettersson, B M Fredrik; Behra, Phani Rama Krishna; Ramesh, Malavika; Dasgupta, Santanu; Bhattacharya, Alok; Kirsebom, Leif A

    2015-06-16

    We provide the genome sequences of the type strains of the polychlorophenol-degrading Mycobacterium chlorophenolicum (DSM43826), the degrader of chlorinated aliphatics Mycobacterium chubuense (DSM44219) and Mycobacterium obuense (DSM44075) that has been tested for use in cancer immunotherapy. The genome sizes of M. chlorophenolicum, M. chubuense, and M. obuense are 6.93, 5.95, and 5.58 Mb with GC-contents of 68.4%, 69.2%, and 67.9%, respectively. Comparative genomic analysis revealed that 3,254 genes are common and we predicted approximately 250 genes acquired through horizontal gene transfer from different sources including proteobacteria. The data also showed that the biodegrading Mycobacterium spp. NBB4, also referred to as M. chubuense NBB4, is distantly related to the M. chubuense type strain and should be considered as a separate species, we suggest it to be named Mycobacterium ethylenense NBB4. Among different categories we identified genes with potential roles in: biodegradation of aromatic compounds and copper homeostasis. These are the first nonpathogenic Mycobacterium spp. found harboring genes involved in copper homeostasis. These findings would therefore provide insight into the role of this group of Mycobacterium spp. in bioremediation as well as the evolution of copper homeostasis within the Mycobacterium genus. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  6. Progression to active tuberculosis, but not transmission, varies by Mycobacterium tuberculosis lineage in The Gambia

    NARCIS (Netherlands)

    de Jong, Bouke C.; Hill, Philip C.; Aiken, Alex; Awine, Timothy; Antonio, Martin; Adetifa, Ifedayo M.; Jackson-Sillah, Dolly J.; Fox, Annette; Deriemer, Kathryn; Gagneux, Sebastien; Borgdorff, Martien W.; McAdam, Keith P. W. J.; Corrah, Tumani; Small, Peter M.; Adegbola, Richard A.

    2008-01-01

    BACKGROUND: There is considerable variability in the outcome of Mycobacterium tuberculosis infection. We hypothesized that Mycobacterium africanum was less likely than M. tuberculosis to transmit and progress to tuberculosis disease. METHODS: In a cohort study of patients with tuberculosis and their

  7. Comparative analysis of mycobacterium and related actinomycetes yields insight into the evolution of mycobacterium tuberculosis pathogenesis

    Directory of Open Access Journals (Sweden)

    McGuire Abigail

    2012-03-01

    Full Text Available Abstract Background The sequence of the pathogen Mycobacterium tuberculosis (Mtb strain H37Rv has been available for over a decade, but the biology of the pathogen remains poorly understood. Genome sequences from other Mtb strains and closely related bacteria present an opportunity to apply the power of comparative genomics to understand the evolution of Mtb pathogenesis. We conducted a comparative analysis using 31 genomes from the Tuberculosis Database (TBDB.org, including 8 strains of Mtb and M. bovis, 11 additional Mycobacteria, 4 Corynebacteria, 2 Streptomyces, Rhodococcus jostii RHA1, Nocardia farcinia, Acidothermus cellulolyticus, Rhodobacter sphaeroides, Propionibacterium acnes, and Bifidobacterium longum. Results Our results highlight the functional importance of lipid metabolism and its regulation, and reveal variation between the evolutionary profiles of genes implicated in saturated and unsaturated fatty acid metabolism. It also suggests that DNA repair and molybdopterin cofactors are important in pathogenic Mycobacteria. By analyzing sequence conservation and gene expression data, we identify nearly 400 conserved noncoding regions. These include 37 predicted promoter regulatory motifs, of which 14 correspond to previously validated motifs, as well as 50 potential noncoding RNAs, of which we experimentally confirm the expression of four. Conclusions Our analysis of protein evolution highlights gene families that are associated with the adaptation of environmental Mycobacteria to obligate pathogenesis. These families include fatty acid metabolism, DNA repair, and molybdopterin biosynthesis. Our analysis reinforces recent findings suggesting that small noncoding RNAs are more common in Mycobacteria than previously expected. Our data provide a foundation for understanding the genome and biology of Mtb in a comparative context, and are available online and through TBDB.org.

  8. Comparative analysis of Mycobacterium and related Actinomycetes yields insight into the evolution of Mycobacterium tuberculosis pathogenesis.

    Science.gov (United States)

    McGuire, Abigail Manson; Weiner, Brian; Park, Sang Tae; Wapinski, Ilan; Raman, Sahadevan; Dolganov, Gregory; Peterson, Matthew; Riley, Robert; Zucker, Jeremy; Abeel, Thomas; White, Jared; Sisk, Peter; Stolte, Christian; Koehrsen, Mike; Yamamoto, Robert T; Iacobelli-Martinez, Milena; Kidd, Matthew J; Maer, Andreia M; Schoolnik, Gary K; Regev, Aviv; Galagan, James

    2012-03-28

    The sequence of the pathogen Mycobacterium tuberculosis (Mtb) strain H37Rv has been available for over a decade, but the biology of the pathogen remains poorly understood. Genome sequences from other Mtb strains and closely related bacteria present an opportunity to apply the power of comparative genomics to understand the evolution of Mtb pathogenesis. We conducted a comparative analysis using 31 genomes from the Tuberculosis Database (TBDB.org), including 8 strains of Mtb and M. bovis, 11 additional Mycobacteria, 4 Corynebacteria, 2 Streptomyces, Rhodococcus jostii RHA1, Nocardia farcinia, Acidothermus cellulolyticus, Rhodobacter sphaeroides, Propionibacterium acnes, and Bifidobacterium longum. Our results highlight the functional importance of lipid metabolism and its regulation, and reveal variation between the evolutionary profiles of genes implicated in saturated and unsaturated fatty acid metabolism. It also suggests that DNA repair and molybdopterin cofactors are important in pathogenic Mycobacteria. By analyzing sequence conservation and gene expression data, we identify nearly 400 conserved noncoding regions. These include 37 predicted promoter regulatory motifs, of which 14 correspond to previously validated motifs, as well as 50 potential noncoding RNAs, of which we experimentally confirm the expression of four. Our analysis of protein evolution highlights gene families that are associated with the adaptation of environmental Mycobacteria to obligate pathogenesis. These families include fatty acid metabolism, DNA repair, and molybdopterin biosynthesis. Our analysis reinforces recent findings suggesting that small noncoding RNAs are more common in Mycobacteria than previously expected. Our data provide a foundation for understanding the genome and biology of Mtb in a comparative context, and are available online and through TBDB.org.

  9. Ctenophthalmus (Ethioctenophthalmus kemmelberg n. sp. (Insecta : Siphonaptera : Ctenophthalmidae, Puce nouvelle de Tanzanie et description de structures internes non signalées chez les Mécoptèroïdes

    Directory of Open Access Journals (Sweden)

    Laudisoit A.

    2007-09-01

    Full Text Available Nous avons récemment décrit deux taxa nouveaux de Siphonaptères (Ctenophthalmus (Ethioctenophthalmus teucqae teucqae et C. (E. teucqae shumeensis Laudisoit & Beaucournu, 2007 du foyer pesteux de Lushoto (Monts Usambara occidentaux, Tanzanie. Nous étudierons ici un taxon nouveau, Ctenophthalmus kemmelberg, puce originale, non seulement par ses segments génitaux, mais aussi par des structures jusqu’à maintenant décrites, à notre connaissance, chez aucun Mécoptèroïde. Elles sont observables chez les femelles uniquement. Nous proposons d’attribuer à ces structures remarquables le nom d’“organes de Teucq”.

  10. Les tumeurs neuro ectodermiques périphériques primitives de localisation thoracique (tumeur d'Askin) chez l'adulte jeune : à propos de deux observations, revue de la littérature

    OpenAIRE

    Brugger , Catherine

    2003-01-01

    Non disponible / Not available; La tumeur d'Askin appartient à la famille des tumeurs neuro ectodermiques périphériques primitives. De localisation thoracique, elle est décrite initialement chez l'enfant, sa survenue chez l'adulte jeune demeure exceptionnelle. Elle est définie comme une tumeur maligne à petites cellules rondes exprimant le gène MIC2 et présentant une translocation chromosomique t(11,22) spécifique. Ses aspects cliniques et radiologiques ne sont pas spécifiques. L'évolution à ...

  11. Distribution épidémiologique de l'infection à VIH chez les femmes enceintes dans les dix régions du Cameroun et implications stratégiques pour les programmes de prévention

    Science.gov (United States)

    Billong, Serge-Clotaire; Fokam, Joseph; Billong, Edson-Joan; Nguefack-Tsague, Georges; Essi, Marie-Josée; Fodjo, Raoul; Sosso, Samuel-Martin; Gomba, Armelle; Mosoko-Jembia, Joseph; Loni-Ekali, Gabriel; Colizzi, Vittorio; Bissek, Anne-Cécile Zoung-Kani; Monebenimp, Francisca; Nfetam, Jean-Bosco Elat

    2015-01-01

    Introduction Le Cameroun se situe dans un contexte d’épidémie généralisée du VIH. La sous-population des femmes enceintes, facilement accessible au sein de la population générale, représente une cible probante pour mener la surveillance du VIH et estimer l’évolution épidémiologique. L'objectif de notre étude était d’évaluer la distribution épidémiologique du VIH chez les femmes enceintes. Méthodes Étude transversale menée en 2012 chez 6521 femmes enceintes (49,3% âgées de 15-24 ans) en première consultation prénatale (CPN1) dans 60 sites des 10 régions Camerounaises. L'algorithme en série a été utilisé pour le sérodiagnostic du VIH. Résultats La prévalence du VIH était de 7,8% (508/6521), avec une différence non significative (p = 0,297) entre milieu rural (7,4%) et milieu urbain (8,1%). En zone rurale, cette prévalence variait de 0,7% à l'Extrême-Nord à 11,8% au Sud. Cependant, en zone urbaine elle variait de 4% à l'Ouest à 11,1% au Sud-Ouest. Suivant l’âge, la prévalence était plus élevée (11,3%) chez les femmes de 35-39 ans. Suivant le niveau de scolarisation, la prévalence du VIH était plus faible (4,4%) chez celles non-scolarisées, et plus élevée (9,3%) chez celles ayant un niveau primaire. Selon la profession, l'infection était plus élevée chez les coiffeuses (15,5%), secrétaires (14,8%), commerçantes (12,9%) et institutrices/enseignantes (10,8%). Conclusion La prévalence du VIH reste élevée chez les femmes enceintes au Cameroun, sans distinction entre milieux rural et urbain. Les stratégies de prévention devraient s'orienter préférentiellement chez les femmes enceintes âgées, celles du niveau d'instruction primaire, et celles du secteur des petites et moyennes entreprises. PMID:26090037

  12. Mycobacterium avium-intracellulare cellulitis occurring with septic arthritis after joint injection: a case report

    Directory of Open Access Journals (Sweden)

    Murdoch David M

    2007-02-01

    Full Text Available Abstract Background Cellulitis caused by Mycobacterium avium-intracellulare has rarely been described. Mycobacterium avium-intracellulare is a rare cause of septic arthritis after intra-articular injection, though the causative role of injection is difficult to ascertain in such cases. Case presentation A 57-year-old with rheumatoid arthritis treated with prednisone and azathioprine developed bilateral painful degenerative shoulder arthritis. After corticosteroid injections into both acromioclavicular joints, he developed bilateral cellulitis centered over the injection sites. Skin biopsy showed non-caseating granulomas, and culture grew Mycobacterium avium-intracellulare. Joint aspiration also revealed Mycobacterium avium-intracellulare infection. Conclusion Although rare, skin and joint infections caused by Mycobacterium avium-intracellulare should be considered in any immunocompromised host, particularly after intra-articular injection. Stains for acid-fast bacilli may be negative in pathologic samples even in the presence of infection; cultures of tissue specimens should always be obtained.

  13. Mycobacterium eburneum sp. nov., a non-chromogenic, fast-growing strain isolated from sputum.

    Science.gov (United States)

    Nouioui, Imen; Carro, Lorena; Teramoto, Kanae; Igual, José M; Jando, Marlen; Del Carmen Montero-Calasanz, Maria; Sutcliffe, Iain; Sangal, Vartul; Goodfellow, Michael; Klenk, Hans-Peter

    2017-09-01

    A polyphasic study was undertaken to establish the taxonomic position of a non-chromogenic, rapidly growing Mycobacterium strain that had been isolated from sputum. The strain, CECT 8775T, has chemotaxonomic and cultural properties consistent with its classification in the genus Mycobacterium and was distinguished from the type strains of closely related mycobacterial species, notably from Mycobacterium paraense DSM 46749T, its nearest phylogenetic neighbour, based on 16S rRNA, hsp65 and rpoB gene sequence data. These organisms were also distinguished by a broad range of chemotaxonomic and phenotypic features and by a digital DNA-DNA relatedness value of 22.8 %. Consequently, the strain is considered to represent a novel species of Mycobacterium for which the name Mycobacterium eburneum sp. nov is proposed; the type strain is X82T (CECT 8775T=DSM 44358T).

  14. Mycobacterium shigaense Causes Lymph Node and Cutaneous Lesions as Immune Reconstitution Syndrome in an AIDS Patient: The Third Case Report of a Novel Strain Non-tuberculous Mycobacterium

    Science.gov (United States)

    Koizumi, Yusuke; Shimizu, Kaoru; Shigeta, Masayo; Minamiguchi, Hitoshi; Hodohara, Keiko; Andoh, Akira; Tanaka, Toshihide; Chikamatsu, Kinuyo; Mitarai, Satoshi; Mikamo, Hiroshige

    2016-01-01

    A 40-year-old man complaining of progressive body weight loss was diagnosed to have acquired immunodeficiency syndrome. Within 2 weeks after the initiation of combination antiretroviral therapy, he developed fever, massive cervical lymphadenopathy and a protruding subcutaneous abscess. A lymph node biopsy and abscess drainage revealed non-caseous granuloma and mycobacterium. The mycobacterium belonged to Runyon II group, but it showed no matches to any previously reported species. According to sequence analyses, the strain was identified as Mycobacterium shigaense. After six months of antimycobacterial treatment, the lesions were all successfully cured. This is the third case report of the novel mycobacterium, M. shigaense, presenting in associatioin with immune reconstitution syndrome. PMID:27853087

  15. Role of genotype® mycobacterium common mycobacteria/additional species assay for rapid differentiation between Mycobacterium tuberculosis complex and different species of non-tuberculous mycobacteria

    Directory of Open Access Journals (Sweden)

    Amresh Kumar Singh

    2013-01-01

    Full Text Available Background: Mycobacterium tuberculosis complex (MTBC and non-tuberculous mycobacteria (NTM may or may not have same clinical presentations, but the treatment regimens are always different. Laboratory differentiation between MTBC and NTM by routine methods are time consuming and cumbersome to perform. We have evaluated the role of GenoType® Mycobacterium common mycobacteria/additional species (CM/AS assay for differentiation between MTBC and different species of NTM in clinical isolates from tuberculosis (TB cases. Materials and Methods: A total of 1080 clinical specimens were collected from January 2010 to June 2012. Diagnosis was performed by Ziehl-Neelsen staining followed by culture in BacT/ALERT 3D system (bioMerieux, France. A total of 219 culture positive clinical isolates (BacT/ALERT® MP cultures were selected for differentiation by p-nitrobenzoic acid (PNB sensitivity test as and BIO-LINE SD Ag MPT64 TB test considering as the gold standard test. Final identification and differentiation between MTBC and different species of NTM were further confirmed by GenoType® Mycobacterium CM/AS assay (Hain Lifescience, Nehren, Germany. Results: Out of 219 BacT/ALERT® MP culture positive isolates tested by PNB as 153 MTBC (69.9% and by GenoType® Mycobacterium CM/AS assay as 159 (72.6% MTBC and remaining 60 (27.4% were considered as NTM species. The GenoType® Mycobacterium CM/AS assay was proved 99.3% sensitive and 98.3% specific for rapid differentiation of MTBC and NTM. The most common NTM species were; Mycobacterium fortuitum 20 (33.3% among rapid growing mycobacteria and Mycobacterium intracellulare 11 (18.3% among slow growing mycobacteria. Conclusion: The GenoType® Mycobacterium assay makes rapid and accurate identification of NTM species as compared with different phenotypic and molecular diagnostic tool and helps in management of infections caused by different mycobacteria.

  16. Prévalence de l'hépatite B chez les personnes infectées par le VIH à ...

    African Journals Online (AJOL)

    Introduction: la co-infection avec l'hépatite B est l'un des défis majeurs de la prise en charge du VIH depuis l'amélioration de l'accès aux antirétroviraux en Afrique. La présente étude visait à estimer la prévalence de l'hépatite B chez les personnes séropositives au VIH à Parakou et décrire les facteurs associés. Méthodes: il ...

  17. Carence en fer, anémie et anémie ferriprive chez les donneurs de sang à Kinshasa, République Démocratique du Congo

    Science.gov (United States)

    Nzengu-Lukusa, Franck; Yuma-Ramazani, Sylvain; Sokolua-Mvika, Eddy; Dilu-Keti, Angèle; Malenga-Nkanga, Blanchard; Shuli, Jean Baptiste; Nzongola-Nkasu, Donatien Kayembe; Mbayo-Kalumbu, Ferdinand; Ahuka-Mundeke, Steve

    2016-01-01

    Introduction En République Démocratique du Congo (RDC), plus d'un million de don de sang ont été réalisés entre 2007 et 2011. Cependant, aucun bilan portant sur la carence en fer et l'anémie ferriprive, conséquence d'un don de sang chez les donneurs de sang (DS), n'est disponible dans ce pays. L'objectif de cette étude était d'estimer la prévalence de la carence en fer, de l'anémie et de l'anémie ferriprive chezles DS au Centre National de Transfusion Sanguine (CNTS) à Kinshasa en RDC. Méthodes Entre Décembre 2012 et Août 2013, une étude transversale a été menée au CNTS où des DS éligibles au don de sang ont été inclus. Les informations socio démographiques et des prélèvements sanguins ont été collectés de manière simultanée au don de sang. La ferritine sérique a été dosée pour évaluer la carence en fer en utilisant la technique ELISA. L'hémogramme a été réalisé en vue d’évaluer et mettre au point l'anémie. Résultats Au total 386 DS ont été inclus dans cette étude. La prévalence de la carence en fer et de l'anémie ferriprive étaient respectivement de 63,2% (244/386) et 25,9% (100/386) des DS. Une anémie a été trouvée chez 36.5% (141/386) au moment du don de sang. Conclusion La carence en fer, l'anémie et l'anémie ferriprive demeurent très fréquentes chez les DS à Kinshasa. Ces résultats suggèrent la révision des tests biologiques utilisés dans le recrutement des DS au CNTS. Par ailleurs le dosage de la ferritine s'impose en routine chez les DS rég PMID:27303590

  18. Anomalies échocardiographiques chez l'hémodialysé chronique: prévalence et facteurs de risqué

    OpenAIRE

    Ezziani, Mariam; Najdi, Adil; Mikou, Souad; Elhassani, Anis; Akrichi, Mohammed Amine; Hanin, Hakim; Arrayhani, Mohammed; Houssaini, Tarik Sqalli

    2014-01-01

    Introduction Les complications cardio-vasculaires sont la principale cause de mortalité et de morbidité chez les patients hémodialysés chroniques. Le but de cette étude est de décrire les différentes atteintes cardiaques à l’échocardiographie transthoracique et de dégager les facteurs associés aux principales atteintes. Méthodes Etude transversale monocentrique incluant des patients adultes hémodialysés depuis plus d'un an et ayant bénéficié d'une échocardiographie transthoracique durant l'an...

  19. La pharmacothérapie du délirium chez les patients atteints de cancer avancé : une étude descriptive

    OpenAIRE

    Rousseau, Mayssa

    2010-01-01

    Les objectifs de la recherche étaient de décrire prospectivement les comportements de prescriptions des médecins spécialistes en soins palliatifs suivant un delirium diagnostiqué chez les patients atteints de cancer avancé et d'évaluer la conformité de ces médecins aux recommandations pharmacologiques pour le traitement du delirium. Les antipsychotiques, les benzodiazepines, les corticostéroïdes et les opioïdes sont les classes thérapeutiques qui ont été retenues et analysées. L'effectif réel...

  20. CONTRIBUTION À L’ÉTUDE DES LIPIDES TISSULAIRES ET PLASMATIQUES CHEZ LE RAT WISTAR MÂLE SOUS RÉGIME HYPERGRAS

    OpenAIRE

    BENSALAH, Meryem

    2012-01-01

    De nos jours, les pathologies associées aux accumulations lipidiques dans l’organisme humain, telle l’obésité, prennent une importance croissante dans les questions de santé. Ces maladies sont consécutives à des apports caloriques superieurs à la dépense énergétique aboutissant à un surplus de stockage des graisses. L’objectif principal de cette étude était d’évaluer l’impact d’un régime hyperlipidique hypercalorique administré pour une période de 8 semaines chez le rat male Wistar (que nous ...