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Sample records for glufosinate ammonium-induced pathogen

  1. Glufosinate Ammonium-Induced Pathogen Inhibition and Defense Responses Culminate in Disease Protection in bar-Transgenic Rice1[C

    Science.gov (United States)

    Ahn, Il-Pyung

    2008-01-01

    Glufosinate ammonium diminished developments of rice (Oryza sativa) blast and brown leaf spot in 35S:bar-transgenic rice. Pre- and postinoculation treatments of this herbicide reduced disease development. Glufosinate ammonium specifically impeded appressorium formation of the pathogens Magnaporthe grisea and Cochliobolus miyabeanus on hydrophobic surface and on transgenic rice. In contrast, conidial germination remained unaffected. Glufosinate ammonium diminished mycelial growth of two pathogens; however, this inhibitory effect was attenuated in malnutrition conditions. Glufosinate ammonium caused slight chlorosis and diminished chlorophyll content; however, these alterations were almost completely restored in transgenic rice within 7 d. Glufosinate ammonium triggered transcriptions of PATHOGENESIS-RELATED (PR) genes and hydrogen peroxide accumulation in transgenic rice and PR1 transcription in Arabidopsis (Arabidopsis thaliana) wild-type ecotype Columbia harboring 35S:bar construct. All transgenic Arabidopsis showed robust hydrogen peroxide accumulation by glufosinate ammonium. This herbicide also induced PR1 transcription in etr1 and jar1 expressing bar; however, no expression was observed in NahG and npr1. Fungal infection did not alter transcriptions of PR genes and hydrogen peroxide accumulation induced by glufosinate ammonium. Infiltration of glufosinate ammonium did not affect appressorium formation of M. grisea in vivo but inhibited blast disease development. Hydrogen peroxide scavengers nullified blast protection and transcriptions of PR genes by glufosinate ammonium; however, they did not affect brown leaf spot progression. In sum, both direct inhibition of pathogen infection and activation of defense systems were responsible for disease protection in bar-transgenic rice. PMID:17981989

  2. Glufosinate ammonium-induced pathogen inhibition and defense responses culminate in disease protection in bar-transgenic rice.

    Science.gov (United States)

    Ahn, Il-Pyung

    2008-01-01

    Glufosinate ammonium diminished developments of rice (Oryza sativa) blast and brown leaf spot in 35S:bar-transgenic rice. Pre- and postinoculation treatments of this herbicide reduced disease development. Glufosinate ammonium specifically impeded appressorium formation of the pathogens Magnaporthe grisea and Cochliobolus miyabeanus on hydrophobic surface and on transgenic rice. In contrast, conidial germination remained unaffected. Glufosinate ammonium diminished mycelial growth of two pathogens; however, this inhibitory effect was attenuated in malnutrition conditions. Glufosinate ammonium caused slight chlorosis and diminished chlorophyll content; however, these alterations were almost completely restored in transgenic rice within 7 d. Glufosinate ammonium triggered transcriptions of PATHOGENESIS-RELATED (PR) genes and hydrogen peroxide accumulation in transgenic rice and PR1 transcription in Arabidopsis (Arabidopsis thaliana) wild-type ecotype Columbia harboring 35S:bar construct. All transgenic Arabidopsis showed robust hydrogen peroxide accumulation by glufosinate ammonium. This herbicide also induced PR1 transcription in etr1 and jar1 expressing bar; however, no expression was observed in NahG and npr1. Fungal infection did not alter transcriptions of PR genes and hydrogen peroxide accumulation induced by glufosinate ammonium. Infiltration of glufosinate ammonium did not affect appressorium formation of M. grisea in vivo but inhibited blast disease development. Hydrogen peroxide scavengers nullified blast protection and transcriptions of PR genes by glufosinate ammonium; however, they did not affect brown leaf spot progression. In sum, both direct inhibition of pathogen infection and activation of defense systems were responsible for disease protection in bar-transgenic rice.

  3. Glufosinate ammonium induces convulsion through N-methyl-D-aspartate receptors in mice.

    Science.gov (United States)

    Matsumura, N; Takeuchi, C; Hishikawa, K; Fujii, T; Nakaki, T

    2001-05-18

    Glufosinate ammonium, a broad-spectrum herbicide, causes convulsion in rodents and humans. Because of the structural similarities between glufosinate and glutamate, the convulsion induced by glufosinate ammonium may be ascribed to glutamate receptor activation. Three N-methyl-D-asparate (NMDA) receptor antagonists, dizocilpine, LY235959, and Compound 40, and an alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA)/kainate receptor antagonist, NBQX, were coadministrated with glufosinate ammonium (80 mg/kg, intraperitoneally) in mice. Statistical analyses showed that the NMDA receptor antagonists markedly inhibited the convulsions, while the AMPA/kainate receptor antagonist had no effect on the convulsion. These results suggest that the convulsion caused by glufosinate ammonium is mediated through NMDA receptors.

  4. Pre- and postnatal exposure to low dose glufosinate ammonium induces autism-like phenotypes in mice.

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    Laugeray, Anthony; Herzine, Ameziane; Perche, Olivier; Hébert, Betty; Aguillon-Naury, Marine; Richard, Olivier; Menuet, Arnaud; Mazaud-Guittot, Séverine; Lesné, Laurianne; Briault, Sylvain; Jegou, Bernard; Pichon, Jacques; Montécot-Dubourg, Céline; Mortaud, Stéphane

    2014-01-01

    Glufosinate ammonium (GLA) is one of the most widely used herbicides in agriculture. As is the case for most pesticides, potential adverse effects of GLA have not been studied from the perspective of developmental neurotoxicity. Early pesticides exposure may weaken the basic structure of the developing brain and cause permanent changes leading to a wide range of lifelong effects on health and/or behavior. Here, we addressed the developmental impact of GLA by exposing female mice to low dose GLA during both pre- and postnatal periods and analyzed potential developmental and behavioral changes of the offspring during infancy and adulthood. A neurobehavioral test battery revealed significant effects of GLA maternal exposure on early reflex development, pup communication, affiliative behaviors, and preference for social olfactory cues, but emotional reactivity and emotional memory remained unaltered. These behavioral alterations showed a striking resemblance to changes seen in animal models of Autistic Spectrum Disorders. At the brain level, GLA maternal exposure caused some increase in relative brain weight of the offspring. In addition, reduced expression of Pten and Peg3 - two genes implicated in autism-like deficits - was observed in the brain of GLA-exposed pups at postnatal day 15. Our work thus provides new data on the link between pre- and postnatal exposure to the herbicide GLA and the onset of autism-like symptoms later in life. It also raises fundamental concerns about the ability of current safety testing to assess risks of pesticide exposure during critical developmental periods.

  5. Perinatal exposure to low dose glufosinate ammonium induces autism-like phenotypes in mice.

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    Anthony eLaugeray

    2014-11-01

    Full Text Available Glufosinate ammonium (GLA is one of the most widely used herbicides in agriculture. As is the case for most pesticides, potential adverse effects of GLA have not been studied from the perspective of developmental neurotoxicity. Early pesticides exposure may weaken the basic structure of the developing brain and cause permanent changes leading to a wide range of lifelong effects on health and/or behavior. Here we addressed the developmental impact of GLA by exposing female mice to low dose GLA during both pre- and postnatal periods and analyzed potential developmental and behavioral changes of the offspring during infancy and adulthood. A neurobehavioral test battery revealed significant effects of GLA maternal exposure on early reflex development, pup communication, affiliative behaviors, and preference for social olfactory cues, but emotional reactivity and emotional memory remained unaltered. These behavioral alterations showed a striking resemblance to changes seen in animal models of Autistic Spectrum Disorders. At the brain level, GLA maternal exposure caused some increase in normalized brain weight of the offspring. In addition, reduced expression of Pten and Peg3 - two genes implicated in autism-like deficits – was observed in the brain of GLA-exposed pups at postnatal day 15. Our work thus provides new data on the link between perinatal exposure to the herbicide GLA and the onset of autism-like symptoms later in life. It also raises fundamental concerns about the ability of current safety testing to assess risks of pesticide exposure during critical developmental periods.

  6. Chronic exposure to glufosinate-ammonium induces spatial memory impairments, hippocampal MRI modifications and glutamine synthetase activation in mice.

    Science.gov (United States)

    Calas, André-Guilhem; Richard, Olivier; Même, Sandra; Beloeil, Jean-Claude; Doan, Bich-Thuy; Gefflaut, Thierry; Même, William; Crusio, Wim E; Pichon, Jacques; Montécot, Céline

    2008-07-01

    Glufosinate-ammonium (GLA), the active compound of a worldwide-used herbicide, acts by inhibiting the plant glutamine synthetase (GS) leading to a lethal accumulation of ammonia. GS plays a pivotal role in the mammalian brain where it allows neurotransmitter glutamate recycling within astroglia. Clinical studies report that an acute GLA ingestion induces convulsions and memory impairment in humans. Toxicological studies performed at doses used for herbicidal activity showed that GLA is probably harmless at short or medium range periods. However, effects of low doses of GLA on chronically exposed subjects are not known. In our study, C57BL/6J mice were treated during 10 weeks three times a week with 2.5, 5 and 10mg/kg of GLA. Effects of this chronic treatment were assessed at behavioral, structural and metabolic levels by using tests of spatial memory, locomotor activity and anxiety, hippocampal magnetic resonance imaging (MRI) texture analysis, and hippocampal GS activity assay, respectively. Chronic GLA treatments have effects neither on anxiety nor on locomotor activity of mice but at 5 and 10mg/kg induce (1) mild memory impairments, (2) a modification of hippocampal texture and (3) a significant increase in hippocampal GS activity. It is suggested that these modifications may be causally linked one to another. Since glutamate is the main neurotransmitter in hippocampus where it plays a crucial role in spatial memory, hippocampal MRI texture and spatial memory alterations might be the consequences of hippocampal glutamate homeostasis modification revealed by increased GS activity in hippocampus. The present study provides the first data that show cerebral alterations after chronic exposure to GLA.

  7. Glufosinate ammonium selection of transformed Arabidopsis.

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    Weigel, Detlef; Glazebrook, Jane

    2006-12-01

    INTRODUCTIONOne of the most commonly used markers for the selection of transgenic Arabidopsis is resistance to glufosinate ammonium, an herbicide that is sold under a variety of trade names including Basta and Finale. Resistance to glufosinate ammonium is conferred by the bacterial bialophos resistance gene (BAR) encoding the enzyme phosphinotricin acetyl transferase (PAT). This protocol describes the use of glufosinate ammonium to select transformed Arabidopsis plants. The major advantage of glufosinate ammonium selection is that it can be performed on plants growing in soil and does not require the use of sterile techniques.

  8. Chronotoxicity of glufosinate ammonium in mice.

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    Yoshiyama, Y; Kobayashi, T; Kondo, R; Tomonaga, F; Ohwada, T

    1995-02-01

    The effect of a circadian-stage dependent dosing schedule on the toxicity of glufosinate was studied in mice. Male ICR mice were housed in a standardized 12:12 light:dark cycle for 3 w. Each animal was given 1500 or 3000 mg glufosinate/kg po. A highly significant circadian rhythm occurred in the resulting mortality, with the highest mortality from doses given during the light phase and the lowest from doses administered during the dark phase. The circadian-stage dependent dosing schedule had a marked influence on the pattern of acute glufosinate toxicity in mice.

  9. 40 CFR 180.473 - Glufosinate ammonium; tolerances for residues.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Glufosinate ammonium; tolerances for... § 180.473 Glufosinate ammonium; tolerances for residues. (a) General. Tolerances are established for residues of the herbicide glufosinate-ammonium (butanoic acid, 2-amino-4-(hydroxymethylphosphinyl...

  10. Characterisation of glufosinate resistance mechanisms in Eleusine indica.

    Science.gov (United States)

    Jalaludin, Adam; Yu, Qin; Zoellner, Peter; Beffa, Roland; Powles, Stephen B

    2017-06-01

    An Eleusine indica population has evolved resistance to glufosinate, a major post-emergence herbicide of global agriculture. This population was analysed for target-site (glutamine synthetase) and non-target-site (glufosinate uptake, translocation and metabolism) resistance mechanisms. Glutamine synthetase (GS) activity extracted from susceptible (S) and resistant (R*) plants was equally sensitive to glufosinate inhibition, with IC 50 values of 0.85 mm and 0.99 mm, respectively. The extractable GS activity was also similar in S and R* samples. Foliar uptake of [ 14 C]-glufosinate did not differ in S and R* plants, nor did glufosinate net uptake in leaf discs. Translocation of [ 14 C]-glufosinate into untreated shoots and roots was also similar in both populations, with 44% to 47% of the herbicide translocated out from the treated leaf 24 h after treatment. The HPLC and LC-MS analysis of glufosinate metabolism revealed no major metabolites in S or R* leaf tissue. Glufosinate resistance in this resistant population is not due to an insensitive GS, or increased activity, or altered glufosinate uptake and translocation, or enhanced glufosinate metabolism. Thus, target-site resistance is likely excluded and the exact resistance mechanism(s) remain to be determined. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  11. Neurological effects of glufosinate poisoning with a brief review.

    Science.gov (United States)

    Watanabe, T; Sano, T

    1998-01-01

    Herbicides containing glufosinate ammonium are widely used in many countries including Japan. Many Japanese cases of accidental and suicidal poisoning by glufosinate have been reported since 1989. We report a case of a 64-year old man who ingested glufosinate in an attempted suicide. The patient suffered mental disturbances and hematological changes together with gastrointestinal effects shortly after ingesting the poison, and later developed generalized convulsions, impaired respiration and circulatory failure. During recovery he exhibited loss of short-term memory (retrograde and anterograde amnesia). Neurotoxicity is a characteristic of glufosinate poisoning, although the mechanism is not clear. From the analysis of clinical symptoms of previously published cases, glufosinate toxicity appears to arise both from the active ingredient and the surfactant in the formulation.

  12. Rapeseed with tolerance to the non selective herbicide glufosinate ammonium

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    Rasche, E. [Hoechst Schering AgrEvo GmbH, Frankfurt am Main (Germany)

    1998-12-31

    Weed control with herbicides is essential to grow rapeseed. Glufosinate Ammonium is used as a non selective herbicide successfully in many countries for over 10 years. It conforms well with ever increasing safety standards for human beings, animals and the environment. The tolerance of rapeseed and other crop plants was achieved by genetic modification. A resistance gene (PAT or BAR) was transfered into previously susceptible rapeseed plants. This new approach allowed the development of Glufosinate Ammonium as an almost ideal selective herbicide. In cooperation with major seed companies and by own breeding programmes new Glufosinate tolerant rapeseed varieties and hybrids are developed. Data on metabolism, toxicity, residues, efficacy etc. were generated to get registration for the selective herbicide use. In addition various studies were done for safety assessments of the PAT gene and the modified rapeseed. In spring 1995 Canadian authorities granted worldwide the first approvals for the selective use of Glufosinate Ammonium (trademark Liberty) and Glufosinate tolerant (trademark and logo Liberty Link) spring rapeseed (Canola). After a successful launch in 1995 about 150.000 ha of Liberty Link Canola were grown and treated with Liberty in 1996. The Liberty Link Canola growers were very well satisfied. In a grower survey 84% stated that they will definitely use the Liberty Link System again. In Europe registrations for Glufosinate Ammonium as a selective herbicide and for the first Glufosinate tolerant rapeseed varieties are expected in the course of 1997. The Liberty Link System will be launched in rapeseed most probably in 1998. (orig.)

  13. A toxicokinetic analysis in a patient with acute glufosinate poisoning.

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    Hirose, Y; Kobayashi, M; Koyama, K; Kohda, Y; Tanaka, T; Honda, H; Hori, Y; Yoshida, K; Kikuchi, M

    1999-05-01

    Incidents of poisoning in humans caused by the ingestion of the glufosinate ammonium containing herbicides are gradually increasing in Japan. This poisoning is characterized by various neurological symptoms such as disturbances of consciousness, convulsions and apnea which appear after an asymptomatic interval of several hours. We studied the toxicokinetics of glufosinate in a patient with this poisoning successfully treated without extracorporeal hemopurification. A 65-year-old male ingested BASTA, which contains 20% w/v of glufosinate ammonium, about 300 ml, more than the estimated human toxic dose. Four and a half hours after ingestion, he showed speech ataxia and systemic tremor. He was prophylactically intubated before the occurrence of serious respiratory failure. After 5 days of artificial ventilation he was extubated and discharged without any sequelae. We studied the serial change of serum glufosinate concentration every 3-6 h and assessed the urinary excretion of glufosinate every 24 h. The absorbed amount of glufosinate was estimated from the cumulative excreted in urine. Toxicokinetic analysis was performed using the two-compartment model. The changes in serum glufosinate concentration exhibited T1/2alpha of 1.84 and T1/2beta of 9.59 h. The apparent distribution volume at beta-phase and the total body clearance were 1.44 l/kg and 86.6 ml/min, respectively. Renal clearance was estimated to be 77.9 ml/min. The indication for extracorporeal hemopurification for this poisoning has been discussed.

  14. Glufosinate Herbicide Intoxication Causing Unconsciousness, Convulsion, and 6th Cranial Nerve Palsy

    OpenAIRE

    Park, Jae-seok; Kwak, Soo-Jung; Gil, Hyo-wook; Kim, So-Young; Hong, Sae-yong

    2013-01-01

    Although glufosinate ammonium herbicides are considered safe when used properly, ingestion of the undiluted form can cause grave outcomes. Recently, we treated a 34-yr-old man who ingested glufosinate ammonium herbicide. In the course of treatment, the patient developed apnea, mental deterioration, and sixth cranial nerve palsy; he has since been discharged with full recovery after intensive care. This case report describes the clinical features of glufosinate intoxication with a focus on six...

  15. Apoptosis induced by glufosinate ammonium in the neuroepithelium of developing mouse embryos in culture.

    Science.gov (United States)

    Watanabe, T

    1997-01-24

    Glufosinate ammonium structurally resembles glutamate and blocks glutamine synthetase. Glufosinate was recently found to be dysmorphogenic in mammals in vitro. The present study examined the cell death induced specifically by glufosinate in the neuroepithelium of mouse embryos. Electron micrograph revealed characteristic chromatin condensation and segregation, extracellular apoptotic bodies, and cell fragments phagocytosed in macrophages in the neuroepithelium of the brain vesicle and neural tube. Moreover neuroepithelial cells undergoing DNA fragmentation were histochemically identified. DNA gel electrophoresis of the neuroepithelial layer revealed a DNA ladder. These observations demonstrate that glufosinate specifically induced apoptosis in the neuroepithelium of embryos.

  16. SENSITIVITY OF MORNINGGLORY PLANTS AND THEIR PROGENIES TO GLUFOSINATE AMMONIUM

    OpenAIRE

    BRITO, I.P.F.S.; MORAES, C.P.; MARCHESI, B.B.; CARBONARI, C.A.; VELINI, E.D.

    2017-01-01

    ABSTRACT The sensitivity of weed species to herbicides is variable, and the behavior can be repeated or not in the next generation. The objective of this study was to evaluate the response of morningglory plants to different doses of glufosinate ammonium and the sensitivity of plant populations and their progenies to the herbicide. Three studies were conducted, all in a greenhouse and repeated in two periods. In the first study, two experiments were conducted to examine the dose-response curv...

  17. First Case of Glufosinate-Resistant Rigid Ryegrass (Lolium rigidum Gaud. in Greece

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    Ilias S. Travlos

    2018-03-01

    Full Text Available Repeated applications of the same herbicide(s, which are characterized by the same mode of action, increase selection pressure, which in turn favours the evolution of herbicide-resistant weeds. Glufosinate is a broad-spectrum non-selective herbicide being used for weed control for many years around the world. Rigid ryegrass (Lolium rigidum Gaud. is an economically important grass weed in Greece. Recent complaints by growers about control failure of rigid ryegrass with glufosinate require further investigation and have been the basis of this study. The objectives of this study were to confirm the existence of glufosinate-resistant L. rigidum in Greece and evaluate the effect of L. rigidum growth stage on glufosinate efficacy. Twenty populations of rigid ryegrass from Greece were sampled from five regions, and whole plant dose–response studies were conducted for five populations under controlled conditions with eight rates of glufosinate (0.0, 0.098, 0.187, 0.375, 0.75, 1.5, 3.0, and 6.0 kg a.i. ha−1. Glufosinate resistance was confirmed in three out of five populations with the level of resistance ranging from three-to seven-fold compared with the susceptible populations based on above-ground biomass reduction. Results also revealed that the level of glufosinate-resistance of rigid ryegrass was dependent on the growth stage at which it was applied.

  18. Field dissipation and storage stability of glufosinate ammonium and its metabolites in soil.

    Science.gov (United States)

    Zhang, Yun; Wang, Kai; Wu, Junxue; Zhang, Hongyan

    2014-01-01

    A simple analytical method was developed to measure concentrations of glufosinate ammonium and its metabolites, 3-methylphosphinico-propionic acid (MPP) and 2-methylphosphinico-acetic acid (MPA), in field soil samples. To determine the minimum quantification limit, samples were spiked at different levels (0.1, 0.5, and 1.0 mg/kg). Soil samples were extracted with ammonium hydroxide solution 5% (v/v), concentrated, and reacted with trimethyl orthoacetate (TMOA) in the presence of acetic acid for derivatization. The derivatives were quantified by gas chromatography (GC) using a flame photometric detector (FPD). The linear correlation coefficients of glufosinate ammonium, MPP, and MPA in soil were 0.991, 0.999, and 0.999, respectively. The recoveries of this method for glufosinate ammonium, MPP, and MPA in soil were 77.2-95.5%, 98.3-100.3%, and 99.3-99.6% with relative standard deviations (RSD) of 1.8-4.1%, 0.4-1.4%, and 1.3-2.0%, respectively. Glufosinate ammonium dissipated rapidly in soil to MPA in hours and gradually degraded to MPP. The half-life of glufosinate ammonium degradation in soil was 2.30-2.93 days in an open field. In soil samples stored at -20°C glufosinate ammonium was stable for two months. The results of this study should provide guidance for the safe application of the herbicide glufosinate ammonium to agricultural products and the environment.

  19. Circadian response of annual weeds to glyphosate and glufosinate.

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    Martinson, Krishona B; Sothern, Robert B; Koukkari, Willard L; Durgan, Beverly R; Gunsolus, Jeffrey L

    2002-03-01

    Five field experiments were conducted in 1998 and 1999 in Minnesota to examine the influence of time of day efficacy of glyphosate [N-(phosphonomethyl)glycine] and glufosinate [2-amino-4-(hydroxymethyl-phosphinyl)butanoic acid] applications on the control of annual weeds. Each experiment was designed to be a randomized complete block with four replications using plot sizes of 3 x 9 m. Glyphosate and glufosinate were applied at rates of 0.421 kg ae/ha and 0.292 kg ai/ha, respectively, with and without an additional adjuvant that consisted of 20% nonionic surfactant and 80% ammonium sulfate. All treatments were applied with water at 94 L/ha. Times of day for the application of herbicide were 06:00h, 09:00h, 12:00h, 15:00h, 18:00h, 21:00h, and 24:00h. Efficacy was evaluated 14 d after application by visual ratings. At 14 d, a circadian response to each herbicide was found, with greatest annual weed control observed with an application occurring between 09:00h and 18:00h and significantly less weed control observed with an application at 06:00h, 21:00h, or 24:00h. The addition of an adjuvant to both herbicides increased overall efficacy, but did not overcome the rhythmic time of day effect. Results of the multiple regression analysis showed that after environmental temperature, time of day was the second most important predictor of percent weed kill. Thus, circadian timing of herbicide application significantly influenced weed control with both glyphosate and glufosinate.

  20. Glufosinate (phosphinothricin), a natural amino acid with unexpected herbicidal properties.

    Science.gov (United States)

    Hoerlein, G

    1994-01-01

    Glufosinate ammonium (phosphinothricin ammonium) (GLA) is the active ingredient of Basta and several other herbicides used worldwide. It is produced as part of the tripeptide L-phosphinothricyl-L-alanyl-L-alanin, which was first isolated from Streptomyces viridichromogenes or Streptomyces hygroscopicus. Its structure is confirmed by degradation and synthesis. Several processes for the preparation of D,L- and L-phosphinothricin are described. Glufosinate is a structural analog of glutamate and inhibits the glutamine synthetase. The result is a rapid build-up of a high ammonia level and a concomitant depletion of glutamine and several other amino acids in the plant. These effects are accompanied by a rapid decline of photosynthetic CO2-fixation and are followed by chlorosis and desiccation. The results of numerous toxicological studies show that glufosinate ammonium and its commercial formulations are safe for users and consumers under the conditions of recommended use. The fast and complete degradation in soil and surface water prevents movement of residues into groundwater. The toxicological threshold levels for all the nontarget organisms tested are well above the potential exposure levels and therefore do not reflect any hazard for nontarget organisms in the ecosystem. Basta is a nonselective foliar applied herbicide for the control of undesirable mono- and dicotyledonous plants in orchards, vineyards, and plantations for minimum tillage, and as a harvest aid. A synthetic phosphinothricin acetyltransferase (PAT) gene has been introduced via Agrobacterium tumefaciens into dicot crops, such as like tobacco, tomato, spring and winter rapeseed, alfalfa, and several horticultural crops. The PAT gene was also successfully introduced into maize protoplasts that could be regenerated into fertile plants. All transgenic crop plants tolerated a two- to threefold field dosage of Basta.

  1. Glufosinate herbicide intoxication causing unconsciousness, convulsion, and 6th cranial nerve palsy.

    Science.gov (United States)

    Park, Jae-seok; Kwak, Soo-Jung; Gil, Hyo-wook; Kim, So-Young; Hong, Sae-yong

    2013-11-01

    Although glufosinate ammonium herbicides are considered safe when used properly, ingestion of the undiluted form can cause grave outcomes. Recently, we treated a 34-yr-old man who ingested glufosinate ammonium herbicide. In the course of treatment, the patient developed apnea, mental deterioration, and sixth cranial nerve palsy; he has since been discharged with full recovery after intensive care. This case report describes the clinical features of glufosinate intoxication with a focus on sixth cranial nerve palsy. Our observation suggests that neurologic manifestations after ingestion of a "low-grade toxicity herbicide" are variable and more complex than that was previously considered.

  2. Ammonium-induced calcium mobilization in 1321N1 astrocytoma cells

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    Hillmann, Petra; Koese, Meryem; Soehl, Kristina; Mueller, Christa E.

    2008-01-01

    High blood levels of ammonium/ammonia (NH 4 + /NH 3 ) are associated with severe neurotoxicity as observed in hepatic encephalopathy (HE). Astrocytes are the main targets of ammonium toxicity, while neuronal cells are less vulnerable. In the present study, an astrocytoma cell line 1321N1 and a neuroblastoma glioma hybrid cell line NG108-15 were used as model systems for astrocytes and neuronal cells, respectively. Ammonium salts evoked a transient increase in intracellular calcium concentrations ([Ca 2+ ] i ) in astrocytoma (EC 50 = 6.38 mM), but not in NG108-15 cells. The ammonium-induced increase in [Ca 2+ ] i was due to an intracellular effect of NH 4 + /NH 3 and was independent of extracellular calcium. Acetate completely inhibited the ammonium effect. Ammonium potently reduced calcium signaling by G q protein-coupled receptors (H 1 and M3) expressed on the cells. Ammonium (5 mM) also significantly inhibited the proliferation of 1321N1 astrocytoma cells. While mRNA for the mammalian ammonium transporters RhBG and RhCG could not be detected in 1321N1 astrocytoma cells, both transporters were expressed in NG108-15 cells. RhBG and RhBC in brain may promote the excretion of NH 3 /NH 4 + from neuronal cells. Cellular uptake of NH 4 + /NH 3 was mainly by passive diffusion of NH 3 . Human 1321N1 astrocytoma cells appear to be an excellent, easily accessible human model for studying HE, which can substitute animal studies, while NG108-15 cells may be useful for investigating the role of the recently discovered Rhesus family type ammonium transporters in neuronal cells. Our findings may contribute to the understanding of pathologic ammonium effects in different brain cells, and to the treatment of hyperammonemia

  3. VARIATION IN THE SENSITIVITY OF WANDERING JEW PLANTS TO GLUFOSINATE AMMONIUM

    OpenAIRE

    BRITO, IVANA PAULA FERRAZ SANTOS DE; MARCHESI, BRUNA BARBOZA; SILVA, ILCA PUERTAS FREITAS E; CARBONARI, CAIO ANTONIO; VELINI, EDIVALDO DOMINGUES

    2017-01-01

    ABSTRACT This study aimed to identify the response of wandering jew (Commelina benghalensis L.) plants to different doses of glufosinate ammonium and the sensitivity of plants populations to the herbicide. Two studies were conducted, both in a greenhouse, and were repeated at different times. In the first study, two experiments were conducted to examine the dose-response curve using seven different doses of the glufosinate ammonium herbicide (0, 50, 100, 200, 400, 800, and 1600 g a.i. ha-1) w...

  4. Glyphosate and glufosinate-ammonium runoff from a corn-growing area in Italy

    OpenAIRE

    Screpanti , Claudio; Accinelli , Cesare; Vicari , Alberto; Catizone , Pietro

    2005-01-01

    International audience; The main objective of this experiment was to estimate field-scale runoff losses of glyphosate and glufosinate-ammonium under natural rainfall conditions. Investigations were carried out at the Runoff Monitoring Station of the University of Bologna (Italy). Glyphosate and glufosinate-ammonium were applied as pre-emergence herbicides on 350-m2 field plots characterized by a uniform slope of 15%. Field plots were cultivated with corn. The persistence and sorption isotherm...

  5. VARIATION IN THE SENSITIVITY OF WANDERING JEW PLANTS TO GLUFOSINATE AMMONIUM

    OpenAIRE

    IVANA PAULA FERRAZ SANTOS DE BRITO; BRUNA BARBOZA MARCHESI; ILCA PUERTAS FREITAS E SILVA; CAIO ANTONIO CARBONARI; EDIVALDO DOMINGUES VELINI

    2017-01-01

    This study aimed to identify the response of wandering jew (Commelina benghalensis L.) plants to different doses of glufosinate ammonium and the sensitivity of plants populations to the herbicide. Two studies were conducted, both in a greenhouse, and were repeated at different times. In the first study, two experiments were conducted to examine the dose-response curve using seven different doses of the glufosinate ammonium herbicide (0, 50, 100, 200, 400, 800, and 1600 g a.i. ha-1) with four ...

  6. Nitrogen loss in Brachiaria decumbens after application of glyphosate or glufosinate-ammonium

    OpenAIRE

    Damin,Virginia; Franco,Henrique Coutinho Junqueira; Moraes,Milton Ferreira; Franco,Ademir; Trivelin,Paulo Cesar Ocheuze

    2008-01-01

    Nitrogen losses from the soil-plant system may be influenced by herbicide applications. In order to evaluate N loss in brachiaria (Brachiaria decumbens) after application of the herbicides glyphosate and glufosinate-ammonium, an experiment was carried out in a greenhouse as a completely randomized design, with three treatments and six replicates. Treatments were as follows: i) desiccation of brachiaria-plants with glyphosate; ii) desiccation of brachiaria-plants with glufosinate-ammonium; and...

  7. A comparative study of direct hemoperfusion and hemodialysis for the removal of glufosinate ammonium.

    Science.gov (United States)

    Tanaka, J; Yamashita, M; Yamamoto, T

    1995-01-01

    BASTA is a herbicide containing glufosinate ammonium 18.5% and a surface-active agent. There were six fatalities in 34 cases of glufosinate ammonium poisoning reported by the Japan Poison Information Center. To evaluate efficacy in the removal of glufosinate ammonium from the blood, two bottles were prepared containing 600 mL of heparinized bovine blood with 1 mL or 3 mL of BASTA. Direct hemoperfusion or hemodialysis was performed for two hours at a flow rate of 50 mL/min. The final glufosinate ammonium concentration of the blood bottle containing 1 mL of BASTA decreased to 96.9% of the initial concentration after direct hemoperfusion and to 0.5% after hemodialysis. The final glufosinate ammonium concentration of the bottle containing 3 mL of BASTA decreased to 62.2% after direct hemoperfusion and to 0.9% after hemodialysis. Hemodialysis is more effective than direct hemoperfusion for removal of glufosinate ammonium from blood.

  8. Glufosinate ammonium--some aspects of its mode of action in mammals.

    Science.gov (United States)

    Hack, R; Ebert, E; Ehling, G; Leist, K H

    1994-05-01

    The broad-spectrum herbicide glufosinate ammonium is a structural analogue of glutamate and acts in plants by inhibition of glutamine synthetase leading to a complete breakdown of ammonia metabolism. Owing to the structural analogy of glufosinate ammonium to glutamate, its effect on various glutamate-utilizing systems needed to be investigated in mammals. Although in laboratory animals glufosinate ammonium causes an inhibition of glutamine synthetase activity in different tissues, this inhibition led to slight increases of glutamate and ammonia levels at high sublethal and lethal doses only. After oral administration for 28 days, glufosinate ammonium had no effect on glutathione and carbohydrate metabolism and no effect on biosynthesis of non-essential amino acids in rats and dogs. Glufosinate ammonium does not interfere with various neurotransmitter receptors in vitro and does not influence the catecholamine neurotransmitter tissue concentrations after iv application. The results of these studies show that--in contrast to the plant metabolism--in mammals the inhibition of glutamine synthetase activity in various tissues does not lead to a breakdown of ammonia metabolism. The mammalian metabolism obviously compensates for this inhibition of glutamine synthetase activity by various other metabolic pathways. It is concluded that under the conditions of recommended use of glufosinate ammonium as an active ingredient in herbicides, a detrimental effect on the health of both users and consumers is extremely unlikely.

  9. Transformation of the herbicide [14C]glufosinate in soils

    International Nuclear Information System (INIS)

    Smith, A.E.

    1989-01-01

    The degradation of 2 μg/g [ 14 C]glufosinate (DL-homoalan-4-ylmethylphosphinic acid) was studied in clay, clay loam, and sandy loam soils at 85% field capacity and at 20 degree C. Over a 4-week period the soils were extracted and analyzed for transformation products by radiochemical and gas chromatographic techniques. In all soils there was release of [ 14 C]carbon dioxide and formation of [ 14 C]-3-(hydroxymethylphosphinyl)propionic acid (MPPA) as major degradation products. Within 21 days, about 55% of the applied 14 C herbicide had been transformed to MPPA in the sandy loam and 19% to [ 14 C]carbon dioxide. After 28 days, approximately 45% of the 14 C herbicide had been transformed to MPPA in the clay and clay loam and 10% released as [ 14 C]carbon dioxide. At all samplings, other 14 C transformation products appeared to be insignificant

  10. Summary of safety evaluation toxicity studies of glufosinate ammonium.

    Science.gov (United States)

    Ebert, E; Leist, K H; Mayer, D

    1990-05-01

    This article reviews the results of toxicity studies to evaluate the safety of the herbicide glufosinate ammonium (GLA) and its formulation (200 g/litre) in laboratory animals. The data show that GLA and its formulation are slightly toxic following oral exposure. In addition, the formulation induced GLA and its formulation are slightly toxic following oral exposure. In addition, the formulation induced slight dermal toxicity and eye irritation. Testing for teratogenicity in rats and rabbits indicated no teratogenic potential, and numerous mutagenicity tests showed GLA to be non-genotoxic. Chronic toxicity testing in rats and dogs yielded no-observable-effect levels of 2 and 5 mg/kg body weight/day, respectively. Oncogenicity studies in rats and mice revealed no carcinogenic potential. On the basis of these toxicity data it is concluded that this herbicide is safe under conditions of recommended use.

  11. Reversible Splenial Lesion Syndrome (RESLES) Following Glufosinate Ammonium Poisoning.

    Science.gov (United States)

    Jeong, Tae Oh; Yoon, Jae Chol; Lee, Jae Baek; Jin, Young Ho; Hwang, Seung Bae

    2015-01-01

    Isolated and reversible lesion restricted to the splenium of the corpus callosum, known as reversible splenial lesion syndrome, have been reported in patients with infection, high-altitude cerebral edema, seizures, antiepileptic drug withdrawal, or metabolic disturbances. Here, we report a 39-year-old female patient with glufosinate ammonium (GLA) poisoning who presented with confusion and amnesia. Diffusion-weighted magnetic resonance imaging of the brain revealed cytotoxic edema of the splenium of the corpus callosum. The lesion was not present on follow-up MR imaging performed 9 months later. We postulate that a GLA-induced excitotoxic mechanism was the cause of this reversible splenial lesion. Copyright © 2015 by the American Society of Neuroimaging.

  12. Biolistic co-transformation of Metarhizium anisopliae var. acridum strain CG423 with green fluorescent protein and resistance to glufosinate ammonium.

    Science.gov (United States)

    Inglis, P W; Aragão, F J; Frazão, H; Magalhães, B P; Valadares-Inglis, M C

    2000-10-15

    Metarhizium anisopliae var. acridum (syn. M. flavoviride) is recognized as a highly specific and virulent mycopathogen of locusts and grasshoppers and is currently being developed as a biological control agent for this group of insects in Brazil. Intact conidia of M. anisopliae var. acridum strain CG423 were transformed using microparticle bombardment. Plasmids used were: (1) pBARKS1 carrying the bar gene of Streptomyces hygroscopicus fused to the Aspergillus nidulans trpC promoter, encoding resistance to glufosinate ammonium (or phosphinothricin) and modified by addition of the telomeric repeat (TTAGGG)(18) of Fusarium oxysporum and 2.pEGFP/gpd/tel carrying a red-shifted variant gene for Aequorea victoria green fluorescent protein (EGFP) which we have fused to the A. nidulans gpd promoter and trpC terminator. Highly fluorescent co-transformants were selected on solid minimal medium containing 100 microg ml(-1) glufosinate ammonium using an inverted microscope with 450-490 nm excitation/510 nm emission filter set. Southern blot analysis of co-transformants revealed varying multiple chromosomal integrations of both bar and egfp genes at both telomeric and non-telomeric loci. Transformants retained pathogenicity in bioassays against Rhammatocerus schistocercoides and showed unaltered lack of pathogenicity against larvae of the non-target insect Anticarsia gemmatalis. One co-transformant from four tested, however, showed a significant, but non-dose-dependent, elevation in virulence against Tenebrio molitor.

  13. Field Dissipation and Storage Stability of Glufosinate Ammonium and Its Metabolites in Soil

    Directory of Open Access Journals (Sweden)

    Yun Zhang

    2014-01-01

    Full Text Available A simple analytical method was developed to measure concentrations of glufosinate ammonium and its metabolites, 3-methylphosphinico-propionic acid (MPP and 2-methylphosphinico-acetic acid (MPA, in field soil samples. To determine the minimum quantification limit, samples were spiked at different levels (0.1, 0.5, and 1.0 mg/kg. Soil samples were extracted with ammonium hydroxide solution 5% (v/v, concentrated, and reacted with trimethyl orthoacetate (TMOA in the presence of acetic acid for derivatization. The derivatives were quantified by gas chromatography (GC using a flame photometric detector (FPD. The linear correlation coefficients of glufosinate ammonium, MPP, and MPA in soil were 0.991, 0.999, and 0.999, respectively. The recoveries of this method for glufosinate ammonium, MPP, and MPA in soil were 77.2–95.5%, 98.3–100.3%, and 99.3–99.6% with relative standard deviations (RSD of 1.8–4.1%, 0.4–1.4%, and 1.3–2.0%, respectively. Glufosinate ammonium dissipated rapidly in soil to MPA in hours and gradually degraded to MPP. The half-life of glufosinate ammonium degradation in soil was 2.30–2.93 days in an open field. In soil samples stored at −20°C glufosinate ammonium was stable for two months. The results of this study should provide guidance for the safe application of the herbicide glufosinate ammonium to agricultural products and the environment.

  14. Field Dissipation and Storage Stability of Glufosinate Ammonium and Its Metabolites in Soil

    Science.gov (United States)

    Zhang, Yun; Wang, Kai; Wu, Junxue; Zhang, Hongyan

    2014-01-01

    A simple analytical method was developed to measure concentrations of glufosinate ammonium and its metabolites, 3-methylphosphinico-propionic acid (MPP) and 2-methylphosphinico-acetic acid (MPA), in field soil samples. To determine the minimum quantification limit, samples were spiked at different levels (0.1, 0.5, and 1.0 mg/kg). Soil samples were extracted with ammonium hydroxide solution 5% (v/v), concentrated, and reacted with trimethyl orthoacetate (TMOA) in the presence of acetic acid for derivatization. The derivatives were quantified by gas chromatography (GC) using a flame photometric detector (FPD). The linear correlation coefficients of glufosinate ammonium, MPP, and MPA in soil were 0.991, 0.999, and 0.999, respectively. The recoveries of this method for glufosinate ammonium, MPP, and MPA in soil were 77.2–95.5%, 98.3–100.3%, and 99.3–99.6% with relative standard deviations (RSD) of 1.8–4.1%, 0.4–1.4%, and 1.3–2.0%, respectively. Glufosinate ammonium dissipated rapidly in soil to MPA in hours and gradually degraded to MPP. The half-life of glufosinate ammonium degradation in soil was 2.30–2.93 days in an open field. In soil samples stored at −20°C glufosinate ammonium was stable for two months. The results of this study should provide guidance for the safe application of the herbicide glufosinate ammonium to agricultural products and the environment. PMID:25374604

  15. Fate of the herbicide glufosinate-ammonium in the sandy, low-organic-carbon aquifer at CFB Borden, Ontario, Canada

    Science.gov (United States)

    Allen-King, Richelle M.; Butler, Barbara J.; Reichert, Barbara

    1995-04-01

    The herbicide glufosinate-ammonium was persistent in aerobic sandy aquifer material in laboratory batch and field in situ microcosms when added at concentrations of 50-400 μg L -1. In contrast, the compound is biotransformed relatively quickly in surface soil. Glufosinate transformation and metabolite (3-methylphosphinyl-propionic acid) production in carbonamended laboratory microcosms demonstrated that the aquifer system was carbon-limited with respect to glufosinate transformation. Microbiological test showed that flufosinateammonium and sodium-glufosinate was be used as a nitrogen source, in the presence of sufficient carbon. Glufosinate was not used by the native microorganisms as a source of phosphorus, nor metabolized as a sole carbon and energy source. Ammonium appeared to be preferred over glufosinate as a nitrogen source. When representative microbial strains isolated from the Borden aquifer were tested, most were glufosinate-ammonium tolerant. Complete inhibition of some isolates was demonstrated only at very high concentrations of 2-4 g L -1. The research suggests that in an aquifer with a relatively low clay content and little labile organic carbon, such as the sandy aquifer at the field site, glufosinate will be persistent and transport will be essentially unretarded. The availability of alternative nitrogen sources was also indicated as a parameter that can affect persistence.

  16. Runoff of the herbicides triclopyr and glufosinate ammonium from oil palm plantation soil.

    Science.gov (United States)

    Tayeb, M A; Ismail, B S; Khairiatul-Mardiana, J

    2017-10-11

    This study focused on the residue detection of the herbicides triclopyr and glufosinate ammonium in the runoff losses from the Tasik Chini oil palm plantation area and the Tasik Chini Lake under natural rainfall conditions in the Malaysian tropical environment. Triclopyr and glufosinate ammonium are post-emergence herbicides. Both herbicides were foliar-sprayed on 0.5 ha of oil palm plantation plots, which were individualized by an uneven slope of 10-15%. Samples were collected at 1, 3, 7, 15, 30, 45, 60, 90, and 120 days after treatment. The concentrations of both herbicides quickly diminished from those in the analyzed sample by the time of collection. The highest residue levels found in the field surface leachate were 0.031 (single dosage, triclopyr), 0.041 (single dosage, glufosinate ammonium), 0.017 (double dosage, triclopyr), and 0.037 μg/kg (double dosage, glufosinate ammonium). The chromatographic peaks were observed at "0" day treatment (2 h after herbicide application). From the applied active ingredients, the triclopyr and glufosinate losses were 0.025 and 0.055%, respectively. The experimental results showed that both herbicides are less potent than other herbicides in polluting water systems because of their short persistence and strong adsorption onto soil clay particles.

  17. Developmental and dysmorphogenic effects of glufosinate ammonium on mouse embryos in culture.

    Science.gov (United States)

    Watanabe, T; Iwase, T

    1996-01-01

    The effects of glufosinate ammonium on embryonic development in mice were examined using whole embryo and micromass cultures of midbrain and limb bud cells. In day 8 embryos cultured for 48 hr, glufosinate caused significant overall embryonic growth retardation and increased embryolethality to 37.5% at 10 micrograms/ml (5.0 x 10(-5) M). All embryos in the treated groups exhibited specific morphological defects including hypoplasia of the prosencephalon (forebrain) (100%) and visceral arches (100%). In day 10 embryos cultured for 24 hr, glufosinate significantly reduced the crown-rump length and the number of somite pairs, and produced a high incidence of morphological defects (84.6%) at 10 micrograms/ml. These embryos were characterized by blister in the lateral head (100%), hypoplasia of prosencephalon (57.1%), and cleft lips (42.9%) at 20 micrograms/ml (10.0 x 10(-5) M). Histological examination of the treated embryos showed numerous cell death (pyknotic debris) present throughout the neuroepithelium in the brain vesicle and neural tube, but did not involve the underlying mesenchyme. In micromass culture, glufosinate inhibited the differentiation of midbrain cells in day 12 embryos with 50% inhibition occurring at 0.55 microgram/ml (2.8 x 10(-6) M). The ratios of 50% inhibition concentration for cell proliferation to cell differentiation in limb bud cells were 0.76 and 1.52 in day 11 and 12 embryos, respectively. These findings indicate that glufosinate ammonium is embryotoxic in vitro. In addition to causing growth retardation, glufosinate specifically affected the neuroepithelium of the brain vesicle and neural tube, leading to neuroepithelial cell death.

  18. Serial ammonia measurement in patients poisoned with glufosinate ammonium herbicide.

    Science.gov (United States)

    Moon, J M; Chun, B J

    2016-05-01

    This study investigated whether ammonia concentrations can predict delayed neurotoxicity development and neurotoxicity latency in glufosinate ammonium (GLA) herbicide-poisoned patients presenting with an alert mental state and stable hemodynamics. This retrospective observational case study included 26 patients divided into 2 groups: neurotoxicity during hospitalization (complicated group) and without neurotoxicity (noncomplicated group). Thirteen patients (50.0%) experienced neurotoxicity at 16 h post-ingestion. Although ammonia concentrations at presentation did not differ significantly between the two groups, the ammonia level in the complicated group increased significantly at the next measurement and remained significantly higher than that in the noncomplicated group until 48 h after ingestion. The peak ammonia concentration before neurotoxicity development was an independent predictor of neurotoxicity (odds ratio: 1.047, 95% confidence interval: 1.010-1.087, p value = 0.014), and the optimal cutoff value of peak ammonia concentration for predicting neurotoxicity was 101.5 μg/dL. The rate of ammonia increase was not associated with the time latency from ingestion to neurotoxicity development. This study showed that serial ammonia measurements in GLA-poisoned patients may identify those who are at high risk of developing neurotoxicity. However, as this study enrolled few patients, further qualified trials are required to confirm our results and to reveal the etiology of hyperammonemia and its causality in neurotoxicity. © The Author(s) 2015.

  19. Two cases of glufosinate poisoning with late onset convulsions.

    Science.gov (United States)

    Tanaka, J; Yamashita, M; Yamashita, M; Matsuo, H; Yamamoto, T

    1998-08-01

    Glufosinate ammonium (GLA), the active ingredient in the non-selective herbicide BASTA (18.5% GLA), is a phosphinic acid analogue of glutamic acid. We report 2 cases of GLA poisoning with late onset convulsions and increased serum CK in spite of low blood concentrations of GLA after hemodialysis. A 69-y-old female was admitted to the emergency department after taking 500 ml of BASTA. On arrival she was conscious, and gut decontamination, hemodialysis and hemoperfusion were performed. However, 8 1/2 hours after ingestion, general convulsions occurred. Her serum OK increased to a peak of 24,900 IU/L on the third day of admission. An 87-y-old male was admitted to the emergency department 3 1/2 hours after taking 200 ml of BASTA and receiving gastric lavage at a local emergency room. On arrival he was conscious, and serial activated charcoal and hemodialysis was performed. Blood concentration of GLA after hemodialysis decreased from 1.56 micrograms/ml to 0.68 micrograms/ml. Thirty hours after admission he had general convulsions. GLA was not detected in the cerebrospinal fluid 6 h after the convulsions. His serum CK increased to a peak of 17,870 IU/L on the fifth day of admission.

  20. Insecticidal activity of glufosinate through glutamine depletion in a caterpillar.

    Science.gov (United States)

    Kutlesa, N J; Caveney, S

    2001-01-01

    The herbicide glufosinate-ammonium (GLA) is a competitive inhibitor of glutamine synthetase (GS), an enzyme converting glutamate to glutamine in both plants and animals. Because GS is essential for ammonia detoxification in plants, GLA treatment disrupts photorespiration by causing a build-up of ammonia and a loss of glutamine in plant tissues. This study reports that GLA applied to leaf surfaces is also toxic to 5th-instar caterpillars of the skipper butterfly Calpodes ethlius (LD50 = 400 mg kg-1). After ingesting GLA, caterpillars stopped feeding and became dehydrated through a loss of rectal function. Caterpillars showed symptoms of neurotoxicity, such as proleg tremors, body convulsions and complete paralysis before death. Incubation of several tissues isolated from normal feeding-stage caterpillars with the GS substrates glutamate and ammonium showed that GLA inhibited GS activity in vitro. Within 24 h of ingesting GLA, caterpillars had a greatly reduced glutamine content and the ammonium ion levels had more than doubled. Injection of ammonium chloride into non-GLA-treated caterpillars had no deleterious effect, suggesting that glutamine depletion, and not a rise in body ammonium, was the primary cause of GLA toxicity following GS inhibition. This was supported by the observation that the onset of the symptoms of GLA poisoning could be postponed by giving GLA-fed caterpillars several subsequent daily injections of glutamine. The effective GLA dose fed to 5th-instar caterpillars in this study was comparable to the amount that might realistically by acquired from feeding on GLA-treated crops.

  1. Comparison of the effectiveness of Basta, Bialaphos and Glufosinate Ammonium for selecting Transformed Oil Palm Tissues

    International Nuclear Information System (INIS)

    A Rahman Nurfahisza; Md Aman Rafiqah; Ghulam Kadir Ahmad Parveez; Omar Abdul Rashid

    2016-01-01

    One of the important requirements for producing transgenic plants is the ability to isolate true transformed cells and regenerate into complete plants without chimera and escapes. Therefore, an efficient selection process is essential. In this study, three different selection agents, namely Basta, bialaphos and glufosinate ammonium were evaluated on embryogenic calli and embryoids, for their effectiveness on selecting transformed oil palm tissues. Un transformed tissues were used in this study as the minimal concentrations which inhibit the growth of the tissues would be the optimum concentrations for selecting the transformed cells. Based on this study, the growth of embryogenic calli was shown to be fully inhibited at 10 mg litre -1 of Basta. Meanwhile, only 3 mg litre -1 of bialaphos and glufosinate ammonium are needed to inhibit the embryogenic calli. For oil palm embryo id cultures, the minimal concentration for Basta was determined at 20 mg litre -1 as compared to 5 mg litre -1 for bialaphos and glufosinate ammonium. This result indicated that a higher concentration of Basta is needed to completely inhibit the growth of oil palm tissues as compared to bialaphos and glufosinate ammonium. Furthermore, these observations revealed that embryogenic calli are more sensitive to the three selection agents as compared to embryoids. The information gained from this study will be used as a guideline to increase the efficiency for selecting transformed oil palm cells and producing transgenic oil palm. (author)

  2. VARIATION IN THE SENSITIVITY OF WANDERING JEW PLANTS TO GLUFOSINATE AMMONIUM

    Directory of Open Access Journals (Sweden)

    IVANA PAULA FERRAZ SANTOS DE BRITO

    2017-01-01

    Full Text Available This study aimed to identify the response of wandering jew (Commelina benghalensis L. plants to different doses of glufosinate ammonium and the sensitivity of plants populations to the herbicide. Two studies were conducted, both in a greenhouse, and were repeated at different times. In the first study, two experiments were conducted to examine the dose-response curve using seven different doses of the glufosinate ammonium herbicide (0, 50, 100, 200, 400, 800, and 1600 g a.i. ha-1 with four replicates each. In the second study, which examined the range in sensitivity of wandering jew plants to glufosinate ammonium, 26 plants were sprayed with a dose of 200 g a.i. ha-1 herbicide. Visual assessments of percent injury and measurements of leaf tissue ammonium content were conducted. The use of untreated wandering jew control plants allowed for the correlation of glufosinate ammonium treatment with the ammonium concentrations in treated plant tissues; the ammonium concentration increased as a function of herbicide application, albeit not linearly with the dose. Ammonium content varied among individuals of the wandering jew plant population.

  3. Analysis of reproductive toxicity and classification of glufosinate-ammonium.

    Science.gov (United States)

    Schulte-Hermann, Rolf; Wogan, Gerald N; Berry, Colin; Brown, Nigel A; Czeizel, Andrew; Giavini, Erminio; Holmes, Lewis B; Kroes, Robert; Nau, Heinz; Neubert, Diether; Oesch, Franz; Ott, Tilmann; Pelkonen, Olavi; Robert-Gnansia, Elisabeth; Sullivan, Frank M

    2006-04-01

    CONCLUSION REGARDING CLASSIFICATION OF GLUFOSINATE-AMMONIUM: Science Partners' Evaluation Group (Evaluation Group) has conducted an independent analysis of the herbicide glufosinate-ammonium (GA) relative to its potential to cause reproductive toxicity in humans. Further, the Evaluation Group has evaluated the implementation of Annex 6 of Commission Directive 2001/59/EC (28th ATP of Council Directive 67/548/EEC) and Council Directive 91/414/EEC, with respect to classification of chemicals posing potential reproductive hazards. After consideration of all information available to us relevant to the potential of glufosinate-ammonium (GA) to cause reproductive toxicity, the Science Partners Evaluation Group concludes that no classification of GA is justified. The following form the basis of this conclusion. There are no human data to suggest that GA causes reproductive toxicity in women or in their conceptus. The issue concerning possible reproductive hazard to humans is raised solely on the basis of positive animal test results that show GA to cause preimplantation or implantation losses in rats. SPECIFICALLY: a. Daily treatment with GA had no detectable effect on the earliest stages of the reproductive sequence including gametogenesis, ovulation, mating and conception; b. Treatment with GA interfered with rat gestation before and at the stage when the conceptus implants into the uterus. This effect occurred at doses of 360 ppm in the feed (corresponding to daily doses of 27.8 mg/kg bw) and above; and c. After implantation, no further effect of GA on prenatal and post-natal development was recognized. Previous concerns that GA might be toxic to embryonic stages after implantation were not supported by the data. Abortions and stillbirth seen were associated with, and regarded as secondary to, maternal toxicity. There was no evidence suggesting the induction of malformations in the offspring. The mechanism underlying this adverse effect in experimental laboratory

  4. Effects of soil phosphorus status on environmental risk assessment of glyphosate and glufosinate-ammonium.

    Science.gov (United States)

    Laitinen, Pirkko; Siimes, Katri; Rämö, Sari; Jauhiainen, Lauri; Eronen, Liisa; Oinonen, Seija; Hartikainen, Helinä

    2008-01-01

    The increased use of herbicides poses a risk to the aquatic environment. Easy and economical methods are needed to identify the fields where specific environment protection measures are needed. Phosphorus (P) and organophosphorus herbicides compete for the same adsorption sites in soil. In this study the relationship between P obtained in routine Finnish agronomic tests (acid ammonium acetate [P(AC)]) and adsorption of glyphosate and glufosinate-ammonium was investigated to determine whether P(AC) values could be used in the risk assessment. The adsorption of glyphosate ((N-(phosphonomethyl)glycine) and glufosinate-ammonium (2-amino-4-(hydroxymethylphosphinyl)butanoic acid) was studied in a clay and a sandy loam soil enriched with increasing amounts of P added as potassium dihydrogen phosphate. Desorption was also determined for some P-enriched soil samples. The adsorption of both herbicides diminished with increasing P(AC) value. The correlations between Freundlich adsorption coefficients obtained in the adsorption tests and P(AC) were nonlinear but significant (r > 0.98) in both soils. The exponential models of the relationship between soil P(AC) values and glyphosate adsorption were found to fit well to an independent Finnish soil data set (P glufosinate-ammonium). The desorption results showed that glufosinate-ammonium sorption is not inversely related to soil P status, and the high correlation coefficients obtained in the test of the model were thus artifacts caused by an abnormal concentration of exchangeable potassium in soil. The solved equations are a useful tool in assessing the leaching risks of glyphosate, but their use for glufosinate-ammonium is questionable.

  5. Bermudagrass (Cynodon spp) dose-response relationships with clethodim, glufosinate and glyphosate.

    Science.gov (United States)

    Webster, Theodore M; Hanna, Wayne W; Mullinix, Benjamin G

    2004-12-01

    Greenhouse studies were conducted to evaluate the sensitivity of three commercial cultivars, eight experimental cultivars and common bermudagrass to clethodim, glufosinate and glyphosate. Each herbicide was applied at eight doses. Data were regressed on herbicide dose using a log-logistic curve (R2 = 0.56-0.95 for clethodim, R2 = 0.60-0.94 for glufosinate, and R2 = 0.70-0.96 for glyphosate). The herbicide rate that elicited a 50% plant response (I50) in the bermudagrass cultivars ranged from 0.04 to 0.19 kg ha(-1) clethodim, 0.19 to 1.33 kg ha(-1) glufosinate and 0.34 to 1.14 kg ha(-1) glyphosate. Relative to other cultivars, common bermudagrass was intermediate in its response to clethodim and among the most tolerant cultivars to glufosinate and glyphosate. TifSport was relatively tolerant to clethodim and glufosinate compared with other cultivars, but relatively sensitive to glyphosate. One cultivar, 94-437, was consistently among the most sensitive cultivars to each of the herbicides. While there were differential herbicide tolerances among the tested bermudagrass cultivars, there did not appear to be any naturally occurring herbicide resistance that could be commercially utilized. However, research indicated that breeding efforts should target herbicide resistance that is at least four times the registered use rate. Also, TifSport and Tifway have been identified as suitable representatives of triploid hybrid bermudagrass cultivars to be used to evaluate the success of turfgrass renovation programs. 2004 Society of Chemical Industry.

  6. Glufosinate ammonium stimulates nitric oxide production through N-methyl D-aspartate receptors in rat cerebellum.

    Science.gov (United States)

    Nakaki, T; Mishima, A; Suzuki, E; Shintani, F; Fujii, T

    2000-09-01

    Glufosinate ammonium, a structural analogue of glutamate, is an active herbicidal ingredient. The neuronal activities of this compound were investigated by use of a microdialysis system that allowed us to measure nitric oxide production in the rat cerebellum in vivo. Kainate (0.3-30 nmol/10 microliter), N-methyl-D-aspartate (NMDA) (3-300 nmol/10 microliter) and glufosinate ammonium (30-3000 nmol/10 microliter), which were administered through the microdialysis probe at a rate of 1 microliter/min for 10 min, stimulated nitric oxide production. The glufosinate ammonium-elicited increase in nitric oxide production was suppressed by an inhibitor of nitric oxide synthase and was antagonized by NMDA receptor antagonists, but not by a kainate/(+/-)-alphaamino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor antagonist. These results suggest that glufosinate ammonium stimulates nitric oxide production through NMDA receptors.

  7. Effects of glufosinate on antioxidant enzymes, subcellular structure, and gene expression in the unicellular green alga Chlorella vulgaris.

    Science.gov (United States)

    Qian, Haifeng; Chen, Wei; Sheng, G Daniel; Xu, Xiaoyan; Liu, Weiping; Fu, Zhengwei

    2008-07-30

    Greater exposure to herbicide increases the likelihood of harmful effects in humans and the environment. Glufosinate, a non-selective herbicide, inhibits glutamine synthetase (GS) and thus blocks ammonium assimilation in plants. In the present study, the aquatic unicellular alga Chlorella vulgaris was chosen to assess the effects of acute glufosinate toxicity. We observed physiological changes during 12-96 h of exposure, and gene transcription during 6-48 h of exposure. Exposure to glufosinate increased malondialdehyde content by up to 2.73 times compared with the control, suggesting that there was some oxidative damage. Electron microscopy also showed that there were some chloroplast abnormalities in response to glufosinate. The activities of the antioxidant enzymes superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) also increased markedly in the presence of glufosinate. Maximum activities of SOD, POD, and CAT were 2.90, 2.91, and 2.48 times that of the control, respectively. These elevated activities may help alleviate oxidative damage. A real-time polymerase chain reaction (PCR) assay showed changes in transcript abundances of three photosynthetic genes, psaB, psbC, and rbcL. The results showed that glufosinate reduced the transcript abundances of the three genes after 12h exposure. The lowest abundances of psaB, psbC and rbcL transcripts in response to glufosinate exposure were 38%, 16% and 43% of those of the control, respectively. Our results demonstrate that glufosinate affects the activities of antioxidant enzymes, disrupts chloroplast ultrastructure, and reduces transcription of photosynthesis-related genes in C. vulgaris.

  8. Takotsubo Cardiomyopathy as a Delayed Complication with a Herbicide Containing Glufosinate Ammonium in a Suicide Attempt: A Case Report

    OpenAIRE

    Tominaga, Keiichiro; Izumi, Manabu; Suzukawa, Masayuki; Shinjo, Takafumi; Izawa, Yoshimitsu; Yonekawa, Chikara; Ano, Masaki; Yamashita, Keisuke; Muronoi, Tomohiro; Mochiduki, Reiko

    2012-01-01

    Background. Glufosinate ammonium has a famous delayed complication as respiratory failure, however, delayed cardiogenic complication is not well known. Objectives. The aim of this study is to report a takotsubo cardiomyopathy as a delayed complication of glufosinate ammonium for suicide attempt. Case Report. A 75-year-old woman ingested about 90 mL of Basta, herbicide for suicide attempt at arousal during sleep. She came to our hospital at twelve hours after ingesting. She was admitted to our...

  9. Effects of glufosinate on antioxidant enzymes, subcellular structure, and gene expression in the unicellular green alga Chlorella vulgaris

    International Nuclear Information System (INIS)

    Qian Haifeng; Chen Wei; Sheng, G. Daniel; Xu Xiaoyan; Liu Weiping; Fu Zhengwei

    2008-01-01

    Greater exposure to herbicide increases the likelihood of harmful effects in humans and the environment. Glufosinate, a non-selective herbicide, inhibits glutamine synthetase (GS) and thus blocks ammonium assimilation in plants. In the present study, the aquatic unicellular alga Chlorella vulgaris was chosen to assess the effects of acute glufosinate toxicity. We observed physiological changes during 12-96 h of exposure, and gene transcription during 6-48 h of exposure. Exposure to glufosinate increased malondialdehyde content by up to 2.73 times compared with the control, suggesting that there was some oxidative damage. Electron microscopy also showed that there were some chloroplast abnormalities in response to glufosinate. The activities of the antioxidant enzymes superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) also increased markedly in the presence of glufosinate. Maximum activities of SOD, POD, and CAT were 2.90, 2.91, and 2.48 times that of the control, respectively. These elevated activities may help alleviate oxidative damage. A real-time polymerase chain reaction (PCR) assay showed changes in transcript abundances of three photosynthetic genes, psaB, psbC, and rbcL. The results showed that glufosinate reduced the transcript abundances of the three genes after 12 h exposure. The lowest abundances of psaB, psbC and rbcL transcripts in response to glufosinate exposure were 38%, 16% and 43% of those of the control, respectively. Our results demonstrate that glufosinate affects the activities of antioxidant enzymes, disrupts chloroplast ultrastructure, and reduces transcription of photosynthesis-related genes in C. vulgaris

  10. Effects of glufosinate on antioxidant enzymes, subcellular structure, and gene expression in the unicellular green alga Chlorella vulgaris

    Energy Technology Data Exchange (ETDEWEB)

    Qian Haifeng; Chen Wei; Sheng, G. Daniel; Xu Xiaoyan; Liu Weiping [College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032 (China); Fu Zhengwei [College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032 (China)], E-mail: azwfu2003@yahoo.com.cn

    2008-07-30

    Greater exposure to herbicide increases the likelihood of harmful effects in humans and the environment. Glufosinate, a non-selective herbicide, inhibits glutamine synthetase (GS) and thus blocks ammonium assimilation in plants. In the present study, the aquatic unicellular alga Chlorella vulgaris was chosen to assess the effects of acute glufosinate toxicity. We observed physiological changes during 12-96 h of exposure, and gene transcription during 6-48 h of exposure. Exposure to glufosinate increased malondialdehyde content by up to 2.73 times compared with the control, suggesting that there was some oxidative damage. Electron microscopy also showed that there were some chloroplast abnormalities in response to glufosinate. The activities of the antioxidant enzymes superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) also increased markedly in the presence of glufosinate. Maximum activities of SOD, POD, and CAT were 2.90, 2.91, and 2.48 times that of the control, respectively. These elevated activities may help alleviate oxidative damage. A real-time polymerase chain reaction (PCR) assay showed changes in transcript abundances of three photosynthetic genes, psaB, psbC, and rbcL. The results showed that glufosinate reduced the transcript abundances of the three genes after 12 h exposure. The lowest abundances of psaB, psbC and rbcL transcripts in response to glufosinate exposure were 38%, 16% and 43% of those of the control, respectively. Our results demonstrate that glufosinate affects the activities of antioxidant enzymes, disrupts chloroplast ultrastructure, and reduces transcription of photosynthesis-related genes in C. vulgaris.

  11. Resistance to glufosinate is proportional to phosphinothricin acetyltransferase expression and activity in LibertyLink(®) and WideStrike(®) cotton.

    Science.gov (United States)

    Carbonari, Caio A; Latorre, Débora O; Gomes, Giovanna L G C; Velini, Edivaldo D; Owens, Daniel K; Pan, Zhiqiang; Dayan, Franck E

    2016-04-01

    Insertion of the gene encoding phosphinothricin acetyltransferase (PAT) has resulted in cotton plants resistant to the herbicide glufosinate. However, the lower expression and commensurate reduction in PAT activity is a key factor in the low level of injury observed in the WideStrike(®) cotton and relatively high level of resistance observed in LibertyLink(®) cotton. LibertyLink(®) cotton cultivars are engineered for glufosinate resistance by overexpressing the bar gene that encodes phosphinothricin acetyltransferase (PAT), whereas the insect-resistant WideStrike(®) cultivars were obtained using the similar pat gene as a selectable marker. The latter cultivars carry some level of resistance to glufosinate which enticed certain farmers to select this herbicide for weed control with WideStrike(®) cotton. The potency of glufosinate on conventional FM 993, insect-resistant FM 975WS, and glufosinate-resistant IMACD 6001LL cotton cultivars was evaluated and contrasted to the relative levels of PAT expression and activity. Conventional cotton was sensitive to glufosinate. The single copy of the pat gene present in the insect-resistant cultivar resulted in very low RNA expression of the gene and undetectable PAT activity in in vitro assays. Nonetheless, the presence of this gene provided a good level of resistance to glufosinate in terms of visual injury and effect on photosynthetic electron transport. The injury is proportional to the amount of ammonia accumulation. The strong promoter associated with bar expression in the glufosinate-resistant cultivar led to high RNA expression levels and PAT activity which protected this cultivar from glufosinate injury. While the insect-resistant cultivar demonstrated a good level of resistance to glufosinate, its safety margin is lower than that of the glufosinate-resistant cultivar. Therefore, farmers should be extremely careful in using glufosinate on cultivars not expressly designed and commercialized as resistant to this

  12. Seletividade de amonio-glufosinate isolado e em mistura com pyrithiobac-sodium em algodoeiro transgênico LL® Selectivity of ammonium-glufosinate applied alone or in mixture with pyrithiobac sodium in transgenic LL® cotton

    Directory of Open Access Journals (Sweden)

    G.B.P. Braz

    2012-12-01

    Full Text Available Com a recente introdução no Brasil de variedades transgênicas de algodoeiro que apresentam resistência ao amonio-glufosinate (LL®, há escassez de informações tanto a respeito da seletividade de reaplicações desse herbicida, quanto no que se refere a misturas com outros herbicidas. Objetivou-se no presente trabalho avaliar a seletividade de aplicações sequenciais de amonio-glufosinate isolado e em associação com pyrithiobac-sodium em algodão transgênico LL®. Dessa forma, foi instalado um experimento em delineamento de blocos casualizados em arranjo fatorial (3x3+1, empregando-se oito repetições. O primeiro fator correspondeu à aplicação dos tratamentos amonio-glufosinate (500 g ha-1 e amonio-glufosinate + pyrithiobac-sodium (500 + 42 g ha-1 e 500 + 56 g ha-1. O segundo fator foi o número de aplicações sequenciais em pós-emergência do algodoeiro (uma, duas ou três. O tratamento adicional foi composto por testemunha sem aplicação de herbicida. A associação do pyrithiobac-sodium ao amonio-glufosinate causou maiores níveis de fitointoxicação inicial, embora não tenham havido mais sintomas duas semanas após as aplicações. A qualidade de fibra do algodoeiro não foi influenciada por nenhum dos tratamentos herbicidas. O amonio-glufosinate isolado foi seletivo para o algodão LL® em até três aplicações em pós-emergência. O algodoeiro apresentou ainda tolerância a uma aplicação da mistura de amonio-glufosinate + pyrithiobac-sodium, e não se observou qualquer efeito negativo sobre a produtividade de algodão em caroço.Due to the recent introduction of transgenic cotton varities with resistance to ammonium-glufosinate (LL® in Brazil, there is a lack of information related both to the selectivity of sequential reapplications of ammonium-glufosinate and to tank mixture with other herbicides. This work aimed to evaluate the selectivity of sequential applications of ammonium-glufosinate isolated or in

  13. Interaction of 2,4-D or Dicamba with Glufosinate for Control of Glyphosate-Resistant Giant Ragweed (Ambrosia trifida L. in Glufosinate-Resistant Maize (Zea mays L.

    Directory of Open Access Journals (Sweden)

    Zahoor A. Ganie

    2017-07-01

    Full Text Available Glyphosate-resistant (GR giant ragweed is a problematic broadleaf weed in crops including maize and soybean in the Midwestern United States. Commercialization of crops with 2,4-D or dicamba and glufosinate resistance will allow post-emergence (POST applications of these herbicides. Therefore, information is needed on how 2,4-D/dicamba will interact with glufosinate in various rate combinations. The objectives of this study were to evaluate the interaction of glufosinate plus 2,4-D and/or dicamba for control of GR giant ragweed, and to determine their effect on GR giant ragweed density, biomass, maize injury, and yield. Field experiments were conducted in 2013 and 2014 in a field infested with GR giant ragweed in Nebraska, United States. The treatments included POST applications of glufosinate (450 or 590 g ai ha-1, 2,4-D, or dicamba at 280 or 560 g ae ha-1 applied alone and in tank-mixtures in glufosinate-resistant maize. The results showed that dicamba applied alone resulted in 56 to 62% and 73 to 83% control at 14 and 28 days after treatment (DAT, respectively, and ≥95% control at 60 DAT or at harvest compared to 17 to 30% and 57 to 73% control with 2,4-D applied alone at 280 and 560 g ai ha-1, respectively. Glufosinate tank-mixed with 2,4-D and/or dicamba consistently provided ≥89% control of GR giant ragweed, except that control with glufosinate plus 2,4-D varied from 80 to 92% at 60 DAT and at harvest. The comparison between the observed and expected control (determined by Colby’s equation suggested an additive interaction between glufosinate and 2,4-D or dicamba for control of GR giant ragweed. Contrast analysis also indicated that GR giant ragweed control with glufosinate plus 2,4-D or dicamba was either consistently higher or comparable with individual herbicides excluding 2,4-D applied alone. Herbicide programs, excluding 2,4-D at 280 g ae ha-1, resulted in ≥80% reduction in GR giant ragweed density. Tank-mixing glufosinate with

  14. Seizures in patients with acute pesticide intoxication, with a focus on glufosinate ammonium.

    Science.gov (United States)

    Park, S; Kim, D E; Park, S Y; Gil, H W; Hong, S Y

    2018-04-01

    The incidence and clinical aspects of seizures remain to be elucidated in patients with acute pesticide intoxication. The present study included subjects who ingested pesticide with the intention of committing suicide and were treated at Soonchunhyang University Hospital (Cheonan, Korea) between January 2011 and December 2014. We analyzed the incidence and characterized the type and frequency of seizure, from the medical records of 464 patients with acute pesticide intoxication, according to the pesticide class. The effect of seizure on the clinical outcome was assessed. The incidence of seizure was 31.5% in patients who ingested glufosinate ammonium {2-amino-4-[hydroxyl (methyl) phosphinoyl] butyrate; ammonium DL-homoalanin-4-yl (methyl) phosphinate}, followed by those who ingested pyrethroid (5.9%) or glycine derivatives (5.4%). All of the seizures developed between 12 and 24 h of pesticide ingestion and had ceased by 72 h after seizure initiation, following treatment with antiseizure medication. Generalized tonic-clonic seizures were the most commonly observed (85.7% of the cases). Multivariable logistic regression analysis showed that the effect of seizure on mortality was not statistically significant. In conclusion, glufosinate ammonium herbicide is the most common seizurogenic pesticide class. Seizure itself was not a risk factor for mortality in patients with acute glufosinate ammonium intoxication.

  15. The effect of several adjuvants on glufosinate effectiveness in Conyza species.

    Science.gov (United States)

    Fernandez-Cerejido, M C; Bastida, F; Menendez, J

    2009-01-01

    The effect of several adjuvants on the effectiveness of glufosinate and the role of adherence and contact angle modifications due to the presence of these adjuvants in the spraying solution on the increase in efficacy observed on the broadleaved weeds Conyza albida and Conyza bonariensis has been determined under laboratory controlled conditions. The adjuvants used on the experiment were a mixture of methyl oleate and palmitate (MO/MP), a dodecylbenzene ammonium sulphonate (DBAS), a paraffinic oil (PO), an alkylglycol ester (AGE), and a lecithin + propionic acid + non ionic surfactant based product (LI-700). Dose-response experiments showed that C. albida displayed higher susceptibility to glufosinate than C. bonariensis, no matter the adjuvant tested. However, none of the mixtures increased the herbicide effectiveness on C. atlbida, with LI 700 and PO showing an antagonistic effect on the herbicide efficacy. On C. bonariensis, MO/MP and DBAS showed significant better results than non-amended glufosinate controls, with LI 700 showing again an antagonistic effect. Both adherence and contact angle studies were inconclusive, since adjuvants with best adherence and contact angle values were not the most effective ones. Therefore, other unknown parameters putatively modified by adjuvants such as herbicide penetration should be questioned.

  16. Effects of glufosinate-ammonium on off crop vegetation--interim results.

    Science.gov (United States)

    De Snoo, G R; De Jong, F M; Van Der Poll, R J; Van Der Linden, M G

    2001-01-01

    In 2000 a field study was conducted at four different locations concerning the effects of low dosages of glufosinate-ammonium, a leaf acting herbicide, on off crop vegetation. Therefore species rich road verges and ditch banks not adapted to a history of herbicide use were sprayed twice with different dosages of glufosinate-ammonium, simulating drift (0, 2, 4, 16, 32 and 64% of the maximum field dose: 800 g a.i./ha). The parameters studied were short term phytotoxic effects and the effects on biomass, species cover and number of species in autumn (Braun-Blanquêt relevés). The results show significant phytotoxic effects at all dosages of glufosinate-ammonium on the non-target vegetation. The low concentrations (2 and 4%) had most impact when applied early in the season (9% average at the 2% dosage and 22% at 4% dosage, after the first spraying. At high dosages (32 and 64%) a decrease of the biomass of the vegetation was found in August. A comparison between treatments in August shows a small decrease in species number and cover in the 64% compared to the control. In the comparison between the spring and August relevés, the decrease in the mean number of species was significantly stronger in the treated plots than in the untreated ones of 4% and higher. For monocotyledons in all treatments except 16%, a significantly stronger decrease in species number was found compared to the untreated. For dicotyledons only the 64% dosage differed from the untreated. Only at the 64% treatment the total cover of species decreased more than in the untreated plots. Since drift percentages of 2-4% can be expected at 1-2 m from a treated plot it can be concluded that the use of glufosinate-ammonium could result in visible short term phytotoxic effects (max 22%) on off-crop vegetation such as ditch banks and verges. There are also indications that effects on the number and cover of species in autumn can occur. Because in future glufosinate-ammonium could be used on a large scale in

  17. The relationship between serum ammonia level and neurologic complications in patients with acute glufosinate ammonium poisoning: A prospective observational study.

    Science.gov (United States)

    Cha, Y S; Kim, H; Lee, Y; Choi, E H; Kim, H I; Kim, O H; Cha, K-C; Lee, K H; Hwang, S O

    2018-06-01

    Glufosinate ammonium poisoning can cause neurological complications even after a symptom-free period. We prospectively investigated the predictors of neurologic complications in acute glufosinate ammonium poisoning and the change of serum ammonia level as a predictor of patient's presence and recovery of neurologic complication. This prospective observational study collected data from consecutive patients diagnosed with acute glufosinate ammonium poisoning between September 2014 and June 2016. Serum ammonia was serially measured. The patients were divided into two groups: the neurologic complication group and the nonneurologic complication group. We also defined 25 other insecticide- or herbicide-poisoned patients as controls. The neurologic complication group included 18 patients (72.0%). The latency period for neurologic complications was within 48-h postingestion. The peak ammonia level was statistically higher in the neurologic complication group than in the control group ( p glufosinate ammonium poisoning, serial serum ammonia level measurements are needed and a serum peak ammonia level greater than 90 μg/dL is a predictor of neurologic complications. Also, it is important to treat the hyperammonemia in acute glufosinate ammonium poisoning.

  18. Forward selection for multiple resistance across the non-selective glyphosate, glufosinate and oxyfluorfen herbicides in Lolium weed species.

    Science.gov (United States)

    Fernández, Pablo; Alcántara, Ricardo; Osuna, María D; Vila-Aiub, Martin M; Prado, Rafael De

    2017-05-01

    In the Mediterranean area, Lolium species have evolved resistance to glyphosate after decades of continual use without other alternative chemicals in perennial crops (olive, citrus and vineyards). In recent years, oxyfluorfen alone or mixed with glyphosate and glufosinate has been introduced as a chemical option to control dicot and grass weeds. Dose-response studies confirmed that three glyphosate-resistant Lolium weed species (L. rigidum, L. perenne, L. multiflorum) collected from perennial crops in the Iberian Peninsula have also evolved resistance to glufosinate and oxyfluorfen herbicides, despite their recent introduction. Based on the LD 50 resistance parameter, the resistance factor was similar among Lolium species and ranged from 14- to 21-fold and from ten- to 12-fold for oxyfluorfen and glufosinate respectively. Similarly, about 14-fold resistance to both oxyfluorfen and glufosinate was estimated on average for the three Lolium species when growth reduction (GR 50 ) was assessed. This study identified oxyfluorfen resistance in a grass species for the first time. A major threat to sustainability of perennial crops in the Iberian Peninsula is evident, as multiple resistance to non-selective glyphosate, glufosinate and oxyfluorfen herbicides has evolved in L. rigidum, L. perenne and L. multiflorum weeds. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  19. Metabolism of the herbicide glufosinate-ammonium in plant cell cultures of transgenic (rhizomania-resistant) and non-transgenic sugarbeet (Beta vulgaris), carrot (Daucus carota), purple foxglove (Digitalis purpurea) and thorn apple (Datura stramonium).

    Science.gov (United States)

    Müller, B P; Zumdick, A; Schuphan, I; Schmidt, B

    2001-01-01

    The metabolism of the herbicide glufosinate-ammonium was investigated in heterotrophic cell suspension and callus cultures of transgenic (bar-gene) and non-transgenic sugarbeet (Beta vulgaris). Similar studies were performed with suspensions of carrot (Daucus carota), purple foxglove (Digitalis purpurea) and thorn apple (Datura stramonium). 14C-labelled chemicals were the (racemic) glufosinate, L-glufosinate, and D-glufosinate, as well as the metabolites N-acetyl L-glufosinate and 3-(hydroxymethylphosphinyl)propionic acid (MPP). Cellular absorption was generally low, but depended noticeably on plant species, substance and enantiomer. Portions of non-extractable residues ranged from 0.1% to 1.2% of applied 14C. Amounts of soluble metabolites resulting from glufosinate or L-glufosinate were between 0.0% and 26.7% of absorbed 14C in non-transgenic cultures and 28.2% and 59.9% in transgenic sugarbeet. D-Glufosinate, MPP and N-acetyl L-glufosinate proved to be stable. The main metabolite in transgenic sugarbeet was N-acetyl L-glufosinate, besides traces of MPP and 4-(hydroxymethylphosphinyl)butanoic acid (MPB). In non-transgenic sugarbeet, glufosinate was transformed to a limited extent to MPP and trace amounts of MPB. In carrot, D stramonium and D purpurea, MPP was also the main product; MPB was identified as a further trace metabolite in D stramonium and D purpurea.

  20. Selectivity of ammonium-glufosinate applied alone or in mixture with pyrithiobac sodium in transgenic LL® cotton

    OpenAIRE

    Braz, G.B.P.; Oliveira Jr, R.S.; Constantin, J.; Raimondi, M.A.; Franchini, L.H.M.; Biffe, D.F.; Arantes, J.G.Z.; Takano, H.K.

    2012-01-01

    Com a recente introdução no Brasil de variedades transgênicas de algodoeiro que apresentam resistência ao amonio-glufosinate (LL®), há escassez de informações tanto a respeito da seletividade de reaplicações desse herbicida, quanto no que se refere a misturas com outros herbicidas. Objetivou-se no presente trabalho avaliar a seletividade de aplicações sequenciais de amonio-glufosinate isolado e em associação com pyrithiobac-sodium em algodão transgênico LL®. Dessa forma, foi instalado um expe...

  1. Vasogenic edema in striatum following ingestion of glufosinate-containing herbicide.

    Science.gov (United States)

    Lee, Hui-Young; Song, Seo-Young; Lee, Seung-Hwan; Lee, Seo-Young; Kim, Sung-Hun; Ryu, Sook-Won

    2009-10-01

    Glufosinate-ammonium (GLA) is a broad-spectrum herbicide used worldwide. We report a patient who attempted suicide by ingesting a liquid herbicide containing GLA. A diffusion-weighted MRI showed cytotoxic edema in the hippocampus as well as vasogenic edema in the striata. To our knowledge, vasogenic edema caused by GLA-containing herbicide involving the striatum has not been reported in association with cytotoxic edema in the hippocampus. We assume that this herbicide affected the central nervous system via different mechanisms to produce both cytotoxic and vasogenic edema in the same patient.

  2. Sensitivity to Glufosinate-ammonium herbicide in plants of Glycine max cultivar INCASoy-27

    Directory of Open Access Journals (Sweden)

    Jorge Liusvert Pérez Pérez

    2014-10-01

    Full Text Available This work had as objective to define the minimum concentration of herbicide Glufosinate-ammonium that inhibits the growth of the soybean plants in greenhouse condition. The soybean plants were tried with different concentrations of herbicide (5; 10; 1 5; 20; 25; 30 mg L-1 and a control without herbicide. The increase of the concentrations increased the necrosis of the plants and the use of 20 mgL-1 Glufosinato de amonio herbicide was sufficient to inhibit the plant growth. These results allow using this method of selection in programs of genetic improvement and selection of transgenic soybean plants

  3. Field Dissipation and Storage Stability of Glufosinate Ammonium and Its Metabolites in Soil

    OpenAIRE

    Zhang, Yun; Wang, Kai; Wu, Junxue; Zhang, Hongyan

    2014-01-01

    A simple analytical method was developed to measure concentrations of glufosinate ammonium and its metabolites, 3-methylphosphinico-propionic acid (MPP) and 2-methylphosphinico-acetic acid (MPA), in field soil samples. To determine the minimum quantification limit, samples were spiked at different levels (0.1, 0.5, and 1.0 mg/kg). Soil samples were extracted with ammonium hydroxide solution 5% (v/v), concentrated, and reacted with trimethyl orthoacetate (TMOA) in the presence of acetic acid f...

  4. Glufosinate ammonium clean-up procedure from water samples using SPE

    Science.gov (United States)

    Tayeb M., A.; Ismail B., S.; Mardiana-Jansar, K.; Ta, Goh Choo; Agustar, Hani Kartini

    2015-09-01

    For the determination of glufosinate ammonium residue in soil and water samples, different solid phase extraction (SPE) sorbent efficiency was studied. Four different SPE sorbents i.e.: CROMABOND PS-H+, CROMABOND PS-OH-, ISOLUTE ENV+, Water Sep-Pak and OASIS HLB were used. Sample clean-up performance was evaluated using high performance liquid chromatography (Agilent 1220 infinity LC) with fluorescence detector. Detection of FMO-derivatives was done at λ ex = 260 nm and λ em= 310 nm. OASIS HLB column was the most suitable for the clean-up in view of the overall feasibility of the analysis.

  5. Integrated Palmer Amaranth Management in Glufosinate-Resistant Cotton: II. Primary, Secondary and Conservation Tillage

    Directory of Open Access Journals (Sweden)

    Michael G. Patterson

    2013-01-01

    Full Text Available A three year field experiment was conducted to evaluate the role of soil inversion, cover crops and spring tillage methods for Palmer amaranth between-row (BR and within-row (WR management in glufosinate-resistant cotton. Main plots were two soil inversion treatments: fall inversion tillage (IT and non-inversion tillage (NIT. Subplots were three cover treatments: crimson clover, cereal rye or none (i.e., winter fallow; and the sub subplots were four secondary spring tillage methods: disking followed by (fb cultivator (DCU, disking fb chisel plow (DCH, disking fb disking (DD and no tillage (NT. Averaged over years and soil inversion, the crimson clover produced maximum cover biomass (4390 kg ha−1 fb cereal rye (3698 kg ha−1 and winter fallow (777 kg ha−1. Two weeks after planting (WAP and before the postemergence (POST application, Palmer amaranth WR and BR density were two- and four-times less, respectively, in IT than NIT. Further, Palmer amaranth WR and BR density were reduced two-fold following crimson clover and cereal rye than following winter fallow at 2 WAP. Without IT, early season Palmer amaranth densities were 40% less following DCU, DCH and DD, when compared with IT. Following IT, no spring tillage method improved Palmer amaranth control. The timely application of glufosinate + S-metolachlor POST tank mixture greatly improved Palmer amaranth control in both IT and NIT systems. The highest cotton yields were obtained with DD following cereal rye (2251 kg ha−1, DD following crimson clover (2213 kg ha−1 and DD following winter fallow (2153 kg ha−1. On average, IT cotton yields (2133 kg ha−1 were 21% higher than NIT (1766 kg ha−1. Therefore, from an integrated weed management standpoint, an occasional fall IT could greatly reduce Palmer amaranth emergence on farms highly infested with glyphosate-resistant Palmer amaranth. In addition, a cereal rye or crimson clover cover crop can effectively reduce early season Palmer

  6. A case of transient diabetes insipidus associated with poisoning by a herbicide containing glufosinate.

    Science.gov (United States)

    Takahashi, H; Toya, T; Matsumiya, N; Koyama, K

    2000-01-01

    The herbicide BASTA (AgrEvo, Germany), containing glufosinate ammonium (20%) and an anionic surfactant, polyoxyethylene alkylether sulfate (33%), is widely used. In acute oral BASTA poisoning, patients develop a variety of clinical signs, including disturbed consciousness, convulsions, and apnea. These effects are suspected to be due to the effects of glufosinate on the central nervous system. A 60-year-old man ingested 500 mL of BASTA herbicide in a suicide attempt. He developed not only unconsciousness, respiratory distress, and convulsions but also an increase in urine output (7885 mL/d), elevated serum sodium (167 mEq/L), elevated plasma osmolality (332 mOsm/kg), and a decrease in both urine osmolality (200 mOsm/kg) and urine specific gravity (1.003), which suggested the development of diabetes insipidus. The plasma level of antidiuretic hormone remained within the normal range (1.3 pg/mL), despite high plasma osmolality. The administration of desmopressin was successful in normalizing urine volume, specific gravity, and osmolality. Serum sodium corrected gradually within 48 hours. The possible mechanisms causing the diabetes insipidus are discussed.

  7. Toxicity of the herbicide glufosinate-ammonium to predatory insects and mites of Tetranychus urticae (Acari: Tetranychidae) under laboratory conditions.

    Science.gov (United States)

    Ahn, Y J; Kim, Y J; Yoo, J K

    2001-02-01

    The toxicities of the herbicide glufosinate-ammonium to three predatory insect and two predatory mite species of Tetranychus urticae Koch were determined in the laboratory by the direct contact application. At a concentration of 540 ppm (a field application rate for weed control in apple orchards), glufosinate-ammonium was almost nontoxic to eggs of Amblyseius womersleyi Schicha, Phytoseiulus persimilis Athias-Henriot, and T. urticae but highly toxic to nymphs and adults of these three mite species, indicating that a common mode of action between predatory and phytophagous mites might be involved. In tests with predatory insects using 540 ppm, glufosinate-ammonium revealed little or no harm to larvae and pupae of Chrysopa pallens Rambur but was slightly harmful to eggs (71.2% mortality), nymphs (65.0% mortality), and adults (57.7% mortality) of Orius strigicollis Poppius. The herbicide showed no direct effect on eggs and adults of Harmonia axyridis (Pallas) but was harmful, slightly harmful, and harmless to first instars (100% mortality), fourth instars (51.1% mortality), and pupae (24.5% mortality), respectively. The larvae and nymphs of predators died within 12 h after treatment, suggesting that the larvicidal and nymphicidal action may be attributable to a direct effect rather than an inhibitory action of chitin synthesis. On the basis of our data, glufosinate-ammonium caused smaller effects on test predators than on T. urticae with the exception of P. persimilis, although the mechanism or cause of selectivity remains unknown. Glufosinate-ammonium merits further study as a key component of integrated pest management.

  8. The effect of high concentrations of glufosinate ammonium on the yield components of transgenic spring wheat (Triticum aestivum L.) constitutively expressing the bar gene.

    Science.gov (United States)

    Áy, Zoltán; Mihály, Róbert; Cserháti, Mátyás; Kótai, Éva; Pauk, János

    2012-01-01

    We present an experiment done on a bar(+) wheat line treated with 14 different concentrations of glufosinate ammonium-an effective component of nonselective herbicides-during seed germination in a closed experimental system. Yield components as number of spikes per plant, number of grains per spike, thousand kernel weight, and yield per plant were thoroughly analysed and statistically evaluated after harvesting. We found that a concentration of glufosinate ammonium 5000 times the lethal dose was not enough to inhibit the germination of transgenic plants expressing the bar gene. Extremely high concentrations of glufosinate ammonium caused a bushy phenotype, significantly lower numbers of grains per spike, and thousand kernel weights. Concerning the productivity, we observed that concentrations of glufosinate ammonium 64 times the lethal dose did not lead to yield depression. Our results draw attention to the possibilities implied in the transgenic approaches.

  9. The Effect of High Concentrations of Glufosinate Ammonium on the Yield Components of Transgenic Spring Wheat (Triticum aestivum L. Constitutively Expressing the bar Gene

    Directory of Open Access Journals (Sweden)

    Zoltán Áy

    2012-01-01

    Full Text Available We present an experiment done on a bar+ wheat line treated with 14 different concentrations of glufosinate ammonium—an effective component of nonselective herbicides—during seed germination in a closed experimental system. Yield components as number of spikes per plant, number of grains per spike, thousand kernel weight, and yield per plant were thoroughly analysed and statistically evaluated after harvesting. We found that a concentration of glufosinate ammonium 5000 times the lethal dose was not enough to inhibit the germination of transgenic plants expressing the bar gene. Extremely high concentrations of glufosinate ammonium caused a bushy phenotype, significantly lower numbers of grains per spike, and thousand kernel weights. Concerning the productivity, we observed that concentrations of glufosinate ammonium 64 times the lethal dose did not lead to yield depression. Our results draw attention to the possibilities implied in the transgenic approaches.

  10. The Effect of High Concentrations of Glufosinate Ammonium on the Yield Components of Transgenic Spring Wheat (Triticum aestivum L.) Constitutively Expressing the bar Gene

    OpenAIRE

    Áy, Zoltán; Mihály, Róbert; Cserháti, Mátyás; Kótai, Éva; Pauk, János

    2012-01-01

    We present an experiment done on a bar + wheat line treated with 14 different concentrations of glufosinate ammonium—an effective component of nonselective herbicides—during seed germination in a closed experimental system. Yield components as number of spikes per plant, number of grains per spike, thousand kernel weight, and yield per plant were thoroughly analysed and statistically evaluated after harvesting. We found that a concentration of glufosinate ammonium 5000 times the lethal dose w...

  11. Transgene Flow from Glufosinate-Resistant Rice to Improved and Weedy Rice in China

    Directory of Open Access Journals (Sweden)

    Yong-liang LU

    2014-09-01

    Full Text Available The development of transgenic rice with novel traits in China can increase rice productivity, but transgene flow to improved or weedy rice has become a major concern. We aimed to evaluate the potential maximum frequencies of transgene flow from glufosinate-resistant rice to improved rice cultivars and weedy rice. Treatments were arranged in randomized complete blocks with three replicates. Experiments were conducted between 2009 and 2010 at the Center for Environmental Safety Supervision and Inspection for Genetically Modified Plants, China National Rice Research Institute, Hangzhou, China. Glufosinate-resistant japonica rice 99-1 was the pollen donor. The pollen recipients were two inbred japonica rice (Chunjiang 016 and Xiushui 09, two inbred indica rice (Zhongzu 14 and Zhongzao 22, two indica hybrid rice (Zhongzheyou 1 and Guodao 1, and one weedy indica rice (Taizhou weedy rice. The offspring of recipients were planted in the field and sprayed with a commercial dose of glufosinate. Leaf tissues of survivors were analyzed by polymerase chain reaction to detect the presence of the transgene. The frequency of gene flow ranged from 0 to 0.488%. In 2009, the order of gene flow frequency was as follows: weedy rice > Chunjiang 016 > Xiushui 09 and Zhongzu 14 > Guodao 1, Zhongzheyou 1 and Zhongzao 22. Gene flow frequencies were generally higher in 2009 than in 2010, but did not differ significantly among rice materials. Gene flow frequency was the highest in weedy rice followed by the inbred japonica rice. The risk of gene flow differed significantly between years and year-to-year variance could mask risk differences among pollen recipients. Gene flow was generally lesser in taller pollen recipients than in shorter ones, but plant height only accounted for about 30% of variation in gene flow. When flowering synchrony was maximized, as in this study, low frequencies of gene flow occurred from herbicide-resistant japonica rice to other cultivars and

  12. Sensitivity of Phaseolus vulgaris cv. `CIAP 7247F' plants to Glufosinate ammonium herbicide in greenhouse

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    Idalmis Bermúdez-Caraballoso

    2014-01-01

    Full Text Available Genetic breeding in Phaseolus by genetic transformation requires an efficient selection system. The present investigation was aimed to determine the minimum lethal concentration of glufosinate-ammonium (Finale ® in beans plants cv. `CIAP 7247F' grown in greenhouse. Different concentrations of the herbicide were applied to the foliage of plants in acclimatization phase (20, 30 y 40 mg l-1 and the control. Results showed that the minimum lethal concentration in plants in acclimatization phase was 30 mg l-1. Results also demonstrated that is possible the use of the herbicide as a selective agent of beans transformants cv. `CIAP 7247F' carrying the bar gene. Keywords: genetic transformation, herbicide, selective agent, tissue culture

  13. Ação dos herbicidas atrazine e glufosinate de amônio no aproveitamento de nitrogênio pelas plantas de milho Herbicides atrazine and ammonium glufosinate action on nitrogen usage by corn plants

    OpenAIRE

    N.G. Fleck; M.A. Rizzardi; R. Neves; D. Agostinetto

    2001-01-01

    A absorção vegetal do nitrogênio (N) presente no solo ou fornecido via fertilização é regulada por um complexo enzimático que age de forma conjunta e ordenada na planta. O objetivo desta pesquisa foi investigar efeitos dos herbicidas atrazine e glufosinate de amônio na absorção do N pelas plantas e os efeitos que exercem em características de plantas de milho. Em um dos experimentos (experimento 1) foram testadas três doses de atrazine (0, 200 e 2.000 g i.a. ha-1) e de glufosinate de amônio (...

  14. Ação dos herbicidas atrazine e glufosinate de amônio no aproveitamento de nitrogênio pelas plantas de milho Herbicides atrazine and ammonium glufosinate action on nitrogen usage by corn plants

    Directory of Open Access Journals (Sweden)

    N.G. Fleck

    2001-08-01

    Full Text Available A absorção vegetal do nitrogênio (N presente no solo ou fornecido via fertilização é regulada por um complexo enzimático que age de forma conjunta e ordenada na planta. O objetivo desta pesquisa foi investigar efeitos dos herbicidas atrazine e glufosinate de amônio na absorção do N pelas plantas e os efeitos que exercem em características de plantas de milho. Em um dos experimentos (experimento 1 foram testadas três doses de atrazine (0, 200 e 2.000 g i.a. ha-1 e de glufosinate de amônio (0; 40 e 80 g i.a. ha-1 e duas doses de N (0 e 90 kg ha-1. No segundo experimento (experimento 2 foram testados três tratamentos herbicidas (atrazine, 200 g i.a. ha-1; glufosinate de amônio, 40 g i.a. ha-1; atrazine + glufosinate de amônio, 200 + 40 g i.a. ha-1; e testemunha, duas fontes de N (uréia e nitrato de amônio e duas doses de N (0 e 100 kg ha-1. Os efeitos dos tratamentos foram avaliados aos 10 e 20 dias após a aplicação (DAA dos herbicidas, no experimento 1, e quando as plantas de milho apresentavam 10 folhas desenvolvidas (15 DAA e no pendoamento do milho (40 DAA, no experimento 2. A partir da análise dos resultados obtidos, constatou-se que aplicação de N em cobertura na cultura do milho promove aumento na maioria dos componentes do rendimento e incrementa em 35% o rendimento de grãos e que esse efeito ocorre de forma independente da fonte de N utilizada: uréia ou nitrato de amônio. Não ocorre interação entre os fatores relacionados aos herbicidas inibidores do fotossistema II (atrazine e da síntese de glutamina (glufosinate de amônio e aplicação de N em cobertura no milho. O uso destes herbicidas em doses reduzidas (abaixo da recomendada, aplicados isoladamente ou combinados, não afetou o rendimento de grãos nem os componentes do rendimento da cultura do milho. O herbicida atrazine tem pequena influência nos teores de clorofila e de N em milho, mas, em algumas situações, sua ação é favorável, especialmente

  15. Fate of the herbicides glyphosate, glufosinate-ammonium, phenmedipham, ethofumesate and metamitron in two Finnish arable soils.

    Science.gov (United States)

    Laitinen, Pirkko; Siimes, Katri; Eronen, Liisa; Rämö, Sari; Welling, Leena; Oinonen, Seija; Mattsoff, Leona; Ruohonen-Lehto, Marja

    2006-06-01

    The fate of five herbicides (glyphosate, glufosinate-ammonium, phenmedipham, ethofumesate and metamitron) was studied in two Finnish sugar beet fields for 26 months. Soil types were sandy loam and clay. Two different herbicide-tolerant sugar beet cultivars and three different herbicide application schedules were used. Meteorological data were collected throughout the study and soil properties were thoroughly analysed. An extensive data set of herbicide residue concentrations in soil was collected. Five different soil depths were sampled. The study was carried out using common Finnish agricultural practices and represents typical sugar beet cultivation conditions in Finland. The overall observed order of persistence was ethofumesate > glyphosate > phenmedipham > metamitron > glufosinate-ammonium. Only ethofumesate and glyphosate persisted until the subsequent spring. Seasonal variation in herbicide dissipation was very high and dissipation ceased almost completely during winter. During the 2 year experiment no indication of potential groundwater pollution risk was obtained, but herbicides may cause surface water pollution. Copyright (c) 2006 Society of Chemical Industry

  16. Takotsubo cardiomyopathy as a delayed complication with a herbicide containing glufosinate ammonium in a suicide attempt: a case report.

    Science.gov (United States)

    Tominaga, Keiichiro; Izumi, Manabu; Suzukawa, Masayuki; Shinjo, Takafumi; Izawa, Yoshimitsu; Yonekawa, Chikara; Ano, Masaki; Yamashita, Keisuke; Muronoi, Tomohiro; Mochiduki, Reiko

    2012-01-01

    Background. Glufosinate ammonium has a famous delayed complication as respiratory failure, however, delayed cardiogenic complication is not well known. Objectives. The aim of this study is to report a takotsubo cardiomyopathy as a delayed complication of glufosinate ammonium for suicide attempt. Case Report. A 75-year-old woman ingested about 90 mL of Basta, herbicide for suicide attempt at arousal during sleep. She came to our hospital at twelve hours after ingesting. She was admitted to our hospital for fear of delayed respiratory failure. Actually, she felt down to respiratory failure, needing a ventilator with intubation at 20 hours after ingesting. Procedure around respiratory management had smoothly done with no delay. Her vital status had been stable, however, she felt down to circulatory failure and diagnosed as Takotsubo cardiomyopathy at about 41 hours after ingestion. There was no trigger activities or events to evoke mental and physical stresses. Conclusion. We could successfully manage takotsubo cardiomyopathy resulted in circulatory failure in a patient with glufosinate poisoning for suicide attempt. Takotsubo cardiomyopathy should be taken into consideration if circulatory failure is observed for unexplained reasons.

  17. Takotsubo Cardiomyopathy as a Delayed Complication with a Herbicide Containing Glufosinate Ammonium in a Suicide Attempt: A Case Report

    Directory of Open Access Journals (Sweden)

    Keiichiro Tominaga

    2012-01-01

    Full Text Available Background. Glufosinate ammonium has a famous delayed complication as respiratory failure, however, delayed cardiogenic complication is not well known. Objectives. The aim of this study is to report a takotsubo cardiomyopathy as a delayed complication of glufosinate ammonium for suicide attempt. Case Report. A 75-year-old woman ingested about 90 mL of Basta, herbicide for suicide attempt at arousal during sleep. She came to our hospital at twelve hours after ingesting. She was admitted to our hospital for fear of delayed respiratory failure. Actually, she felt down to respiratory failure, needing a ventilator with intubation at 20 hours after ingesting. Procedure around respiratory management had smoothly done with no delay. Her vital status had been stable, however, she felt down to circulatory failure and diagnosed as Takotsubo cardiomyopathy at about 41 hours after ingestion. There was no trigger activities or events to evoke mental and physical stresses. Conclusion. We could successfully manage takotsubo cardiomyopathy resulted in circulatory failure in a patient with glufosinate poisoning for suicide attempt. Takotsubo cardiomyopathy should be taken into consideration if circulatory failure is observed for unexplained reasons.

  18. Different rates of synthesis and degradation of two chloroplastic ammonium-inducible NADP-specific glutamate dehydrogenase isoenzymes during induction and deinduction in Chlorella sorokiniana cells

    International Nuclear Information System (INIS)

    Bascomb, N.F.; Prunkard, D.E.; Schmidt, R.R.

    1987-01-01

    The kinetics of accumulation (per milliliter of culture) of the α- and β-subunits, associated with chloroplast-localized ammonium inducible nicotinamide adenine dinucleotide phosphate-specific glutamate dehydrogenase (NADP-GDH) isoenzymes, were measured during a 3 hour induction of synchronized daughter cells of Chlorella sorokiniana in 29 millimolar ammonium medium under photoautotrophic conditions. The β-subunit holoenzyme(s) accumulated in a linear manner for 3 hours without an apparent induction lag. A 40 minute induction lag preceded the accumulation of the α-subunit holoenzyme(s). After 120 minutes, the α-subunit ceased accumulating and thereafter remained at a constant level. From pulse-chase experiments, using 35 SO 4 and immunochemical procedures, the rate of synthesis of the α-subunit was shown to be greater than the β-subunit during the first 80 minutes of induction. The α- and β-subunits had different rates of degradation during the induction period (t/sub 1/2/ = 50 versus 150 minutes, respectively) and during the deinduction period (t/sub 1/2/ = 5 versus 13.5 minutes) after removal of ammonium from the culture. During deinduction, total NADP-GDH activity decreased with a half-time of 9 minutes. Cycloheximide completely inhibited the synthesis and degradation of both subunits. A model for regulation of expression of the NADP-GDH gene was proposed

  19. Hyperammonemia following glufosinate-containing herbicide poisoning: a potential marker of severe neurotoxicity.

    Science.gov (United States)

    Mao, Yan-Chiao; Wang, Jiaan-Der; Hung, Dong-Zong; Deng, Jou-Fang; Yang, Chen-Chang

    2011-01-01

    Glufosinate-ammonium (GLA) is the active ingredient of certain widely used non-selective contact herbicides ("e.g.," Basta). Although it is thought to be much less toxic to humans than to plants, deliberate ingestion of GLA could still lead to serious effects ("e.g.," neurotoxicity) or even death. Three cases presented with delayed-onset neurotoxicity including stupor, delirium, seizures, coma, and amnesia after ingesting large amount of Basta. Considering that GLA could irreversibly inhibit glutamine synthetase (GS) in plants, we performed serial measurements of serum ammonia in those patients and revealed marked hyperammonemia in all of them. All patients recovered with the sequelae of persistent amnesia after receiving intensive care and hemodialysis. We speculated that the occurrence of hyperammonemia might at least be partially related to GS inhibition in humans. Moreover, hyperammonemia could serve as a potential marker of severe neurotoxicity, especially prolonged amnesia, following massive ingestion of GLA-containing herbicides. The possible dose-response relation between GLA exposure and serum ammonia level, however, needs more investigations.

  20. Perinatal Exposure to Glufosinate Ammonium Herbicide Impairs Neurogenesis and Neuroblast Migration through Cytoskeleton Destabilization.

    Science.gov (United States)

    Herzine, Ameziane; Laugeray, Anthony; Feat, Justyne; Menuet, Arnaud; Quesniaux, Valérie; Richard, Olivier; Pichon, Jacques; Montécot-Dubourg, Céline; Perche, Olivier; Mortaud, Stéphane

    2016-01-01

    Neurogenesis, a process of generating functional neurons from neural precursors, occurs throughout life in restricted brain regions such as the subventricular zone (SVZ). During this process, newly generated neurons migrate along the rostral migratory stream to the olfactory bulb to replace granule cells and periglomerular neurons. This neuronal migration is pivotal not only for neuronal plasticity but also for adapted olfactory based behaviors. Perturbation of this highly controlled system by exogenous chemicals has been associated with neurodevelopmental disorders. We reported recently that perinatal exposure to low dose herbicide glufosinate ammonium (GLA), leads to long lasting behavioral defects reminiscent of Autism Spectrum Disorder-like phenotype in the offspring (Laugeray et al., 2014). Herein, we demonstrate that perinatal exposure to low dose GLA induces alterations in neuroblast proliferation within the SVZ and abnormal migration from the SVZ to the olfactory bulbs. These disturbances are not only concomitant to changes in cell morphology, proliferation and apoptosis, but are also associated with transcriptomic changes. Therefore, we demonstrate for the first time that perinatal exposure to low dose GLA alters SVZ neurogenesis. Jointly with our previous work, the present results provide new evidence on the link between molecular and cellular consequences of early life exposure to the herbicide GLA and the onset of ASD-like phenotype later in life.

  1. Resistance to Phosphinothricin (Glufosinate) and Its Utilization as a Nitrogen Source by Chlamydomonas reinhardtii.

    Science.gov (United States)

    Franco, A R; Lopez-Siles, F J; Cardenas, J

    1996-10-01

    Wild-type strain 21gr of the green alga Chlamydomonas reinhardtii was resistant to the ammonium salt of l-phosphinothricin (PPT, also called glufosinate), an irreversible inhibitor of glutamine synthetase activity and the main active component of the herbicide BASTA (AgrEvo, Frankfurt am Main, Germany). Under the same conditions, however, this strain was highly sensitive to l-methionine-S-sulfoximine, a structural analog of PPT which has been reported to be 5 to 10 times less effective than PPT as an inhibitor in plants. Moreover, this alga was able to grow with PPT as the sole nitrogen source when this compound was provided at low concentrations. This utilization of PPT was dependent upon the addition of acetate and light and did not take place in the presence of ammonium. Resistance was due neither to the presence of N-acetyltransferase or transaminase activity nor to the presence of glutamine synthetase isoforms resistant to PPT. By using l-[methyl-(sup14)C]PPT, we demonstrated that resistance is due to lack of PPT transport into the cells. This strongly suggests that PPT and l-methionine-S-sulfoximine enter the cells through different systems. Growth with PPT is supported by its deamination by an l-amino acid oxidase activity which has been previously described to be located at the periplasm.

  2. Characterization of seizures induced by acute exposure to an organophosphate herbicide, glufosinate-ammonium.

    Science.gov (United States)

    Calas, André-Guilhem; Perche, Olivier; Richard, Olivier; Perche, Astrid; Pâris, Arnaud; Lauga, Fabien; Herzine, Ameziane; Palomo, Jennifer; Ardourel, Marie-Yvonne; Menuet, Arnaud; Mortaud, Stéphane; Pichon, Jacques; Montécot-Dubourg, Céline

    2016-05-04

    Glufosinate-ammonium (GLA), the active component of a widely used herbicide, induces convulsions in rodents and humans. In mouse, intraperitoneal treatment with 75 mg/kg GLA generates repetitive tonic-clonic seizures associated with 100% mortality within 72 h after treatment. In this context, we characterized GLA-induced seizures, their histological consequences and the effectiveness of diazepam treatment. Epileptic discharges on electroencephalographic recordings appeared simultaneously in the hippocampus and the cerebral cortex. Diazepam treatment at 6 h immediately stopped the seizures and prevented animal death. However, intermittent seizures were recorded on electroencephalogram from 6 h after diazepam treatment until 24 h, but had disappeared after 15 days. In our model, neuronal activation (c-Fos immunohistochemistry) was observed 6 h after GLA exposure in the dentate gyrus, CA1, CA3, amygdala, piriform and entorhinal cortices, indicating the activation of the limbic system. In these structures, Fluoro-Jade C and Cresyl violet staining did not show neuronal suffering. However, astroglial activation was clearly observed at 24 h and 15 days after GLA treatment in the amygdala, piriform and entorhinal cortices by PCR quantitative, western blot and immunohistochemistry. Concomitantly, glutamine synthetase mRNA expression (PCR quantitative), protein expression (western blot) and enzymatic activity were upregulated. In conclusion, our study suggests that GLA-induced seizures: (a) involved limbic structures and (b) induced astrocytosis without neuronal degeneration as an evidence of a reactive astrocyte beneficial effect for neuronal protection.

  3. Glufosinate aerogenic exposure induces glutamate and IL-1 receptor dependent lung inflammation.

    Science.gov (United States)

    Maillet, Isabelle; Perche, Olivier; Pâris, Arnaud; Richard, Olivier; Gombault, Aurélie; Herzine, Ameziane; Pichon, Jacques; Huaux, Francois; Mortaud, Stéphane; Ryffel, Bernhard; Quesniaux, Valérie F J; Montécot-Dubourg, Céline

    2016-11-01

    Glufosinate-ammonium (GLA), the active component of an herbicide, is known to cause neurotoxicity. GLA shares structural analogy with glutamate. It is a powerful inhibitor of glutamine synthetase (GS) and may bind to glutamate receptors. Since these potentials targets of GLA are present in lung and immune cells, we asked whether airway exposure to GLA may cause lung inflammation in mice. A single GLA exposure (1 mg/kg) induced seizures and inflammatory cell recruitment in the broncho-alveolar space, and increased myeloperoxidase (MPO), inducible NO synthase (iNOS), interstitial inflammation and disruption of alveolar septae within 6-24 h. Interleukin 1β (IL-1β) was increased and lung inflammation depended on IL-1 receptor 1 (IL-1R1). We demonstrate that glutamate receptor pathway is central, since the N-methyl-D-aspartate (NMDA) receptor inhibitor MK-801 prevented GLA-induced lung inflammation. Chronic exposure (0.2 mg/kg 3× per week for 4 weeks) caused moderate lung inflammation and enhanced airway hyperreactivity with significant increased airway resistance. In conclusion, GLA aerosol exposure causes glutamate signalling and IL-1R-dependent pulmonary inflammation with airway hyperreactivity in mice. © 2016 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.

  4. Cholinesterase activities and behavioral changes in Hypsiboas pulchellus (Anura: Hylidae) tadpoles exposed to glufosinate ammonium herbicide.

    Science.gov (United States)

    Peltzer, Paola M; Junges, Celina M; Attademo, Andrés M; Bassó, Agustín; Grenón, Paula; Lajmanovich, Rafael C

    2013-09-01

    In this study, amphibian tadpoles of Hypsiboas pulchellus were exposed to herbicide Liberty®, which contains glufosinate ammonium (GLA), for 48 h to the following concentrations: 0 (control), 3.55, 4.74, 6.32, 8.43, 11.25, 15, 20, 26.6, and 35.5 mg GLA L(-1). Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities, as well as swimming capabilities (swimming speed and mean distance) were measured in tadpoles whose concentrations displayed survival rates > 85 %. Our results reveal that sublethal concentrations of GLA significantly inhibited both AChE and BChE activities in tadpoles with respect to the control, showing a concentration-dependent inhibitory effect. The highest inhibition percentages of AChE (50.86%) and BChE (53.02%) were registered in tadpoles exposed to 15 mg GLA L(-1). At this concentration, a significant increase of the swimming speed and mean distance were found in exposed tadpoles with respect to the control, as well as a negative and significant correlation between swimming speed and BChE activity, thus suggesting that this enzyme inhibition is related to an increase in swimming speed. Therefore, exposure of tadpoles to GLA in the wild at concentrations similar to those tested here may have adverse consequences at population level because neurotransmission and swimming performance are essential for tadpole performance and survival.

  5. Glufosinate-ammonium reduces growth and aflatoxin B1 production by Aspergillus flavus.

    Science.gov (United States)

    Tubajikat, K M; Damann, K E

    2002-09-01

    The herbicide glufosinate-ammonium (GA) [butanoic acid, 2-amino-4-(hydroxymethylphosphinyl)-ammonium salt] was tested at concentrations from 2 to 2,000 g GA per ml for activity against growth and aflatoxin B1 (AFB) production by the mycotoxigenic fungus Aspergillus flavus Link:Fr. The highest concentration (2,000 microg GA per ml) reduced colony diameter of A. flavus strain AF13 by 80%. AFB1 production was inhibited by 90% at this concentration. Reduction in mycelial dry weight and AFB1 production in response to GA application ranged from 17.2 to 97.1% and from 39.1 to 90.1%, respectively. Of four concentrations tested, 2 microg GA per ml was weakly inhibitory. In the kernel screening assay, AFB1 production was inhibited 60 to 91% when kernels were preimmersed or immersed 5 days after incubation in 200 microg GA per ml. Both concentrations (2 and 200 microg GA per ml) reduced seed germination by 25 to 50%. Results indicate that GA has an inhibitory effect on growth and AFB1 production by A. flavus.

  6. Protein binding of glufosinate and factors affecting it revealed by an equilibrium dialysis technique.

    Science.gov (United States)

    Hori, Y; Koyama, K; Fujisawa, M; Nakajima, M; Shimada, K; Hirose, Y; Kohda, Y; Akuzawa, H

    2001-09-01

    We investigated the protein binding of glufosinate ammonium (GLF) and several factors affecting this binding using human serum albumin (HSA) and human volunteer serum under various conditions. The mean ratios of the free GLF (RFr-GLF) to 4% HSA were examined in the sera of patients described elsewhere at GLF levels from 1 microg/mL to 500 microg/mL; the range was found to be only from 0.80 to 0.88. Neither the incubation temperature nor buffers containing different chloride ion concentrations had any effect on the RFr-GLF to HSA. Moreover, the addition of heparin, glycoprotein-alpha1-acid (AAG), and sodium azide had no effect on the RFr-GLF. However, pH of the isotonic phosphate buffer and the addition of palmitic or oleic acid were seen to have an effect. In this study, the mean RFr-GLF to healthy human serum was 0.99. This high value was evidenced that GLF was rapidly excreted through the renal route.

  7. Perinatal exposure to glufosinate ammonium herbicide impairs neurogenesis and neuroblast migration through cytoskeleton destabilization

    Directory of Open Access Journals (Sweden)

    Ameziane Herzine

    2016-08-01

    Full Text Available Neurogenesis, a process of generating functional neurons from neural precursors, occurs throughout life in restricted brain regions such as the subventricular zone (SVZ. During this process, newly generated neurons migrate along the rostral migratory stream to the olfactory bulb to replace granule cells and periglomerular neurons. This neuronal migration is pivotal not only for neuronal plasticity but also for adapted olfactory based behaviors. Perturbation of this highly controlled system by exogenous chemicals has been associated with neurodevelopmental disorders. We reported recently that perinatal exposure to low dose herbicide glufosinate ammonium (GLA, leads to long lasting behavioral defects reminiscent of Autism Spectrum Disorder-like phenotype in the offspring (Laugeray, Herzine et al. 2014 . Herein, we demonstrate that perinatal exposure to low dose GLA induces alterations in neuroblast proliferation within the SVZ and abnormal migration from the SVZ to the olfactory bulbs. These disturbances are not only concomitant to changes in cell morphology, proliferation and apoptosis, but are also associated with transcriptomic changes. Therefore, we demonstrate for the first time that perinatal exposure to low dose GLA alters SVZ neurogenesis. Jointly with our previous work, the present results provide new evidence on the link between molecular and cellular consequences of early life exposure to the herbicide GLA and the onset of ASD-like phenotype later in life.

  8. Glyphosate and glufosinate detection at electrogenerated NiAl-LDH thin films

    Energy Technology Data Exchange (ETDEWEB)

    Khenifi, Aicha [Laboratoire des Materiaux Inorganiques, UMR CNRS 6002, Universite Blaise Pascal, Clermont-Ferrand (France); Laboratoire de physico-chimie des materiaux, catalyse et environnement Usto, Oran, El M' nouar (Algeria); Derriche, Zoubir [Laboratoire de physico-chimie des materiaux, catalyse et environnement Usto, Oran, El M' nouar (Algeria); Forano, Claude; Prevot, Vanessa [Laboratoire des Materiaux Inorganiques, UMR CNRS 6002, Universite Blaise Pascal, Clermont-Ferrand (France); Mousty, Christine, E-mail: Christine.Mousty@univ-bpclermont.fr [Laboratoire des Materiaux Inorganiques, UMR CNRS 6002, Universite Blaise Pascal, Clermont-Ferrand (France); Scavetta, Erika, E-mail: scavetta@fci.unibo.it [Laboratorio di Chimica Analitica, Dipartimento di Chimica Fisica ed Inorganica, Universita degli Studi di Bologna (Italy); Ballarin, Barbara; Guadagnini, Lorella; Tonelli, Domenica [Laboratorio di Chimica Analitica, Dipartimento di Chimica Fisica ed Inorganica, Universita degli Studi di Bologna (Italy)

    2009-11-10

    An amperometric sensor based on Ni{sub 1-x}Al{sub x}(OH){sub 2}NO{sub 3x}.nH{sub 2}O layered double hydroxide (LDH) has been developed for the electrochemical analysis in one step of two herbicides: glyphosate (N-(phosphonomethyl)glycine, Glyp) and glufosinate ((DL-homoalanine-4-yl)-methylphosphinic acid, Gluf). NiAl-LDH was prepared by coprecipitation or by electrodeposition at the Pt electrode surface. Inorganic films were fully characterized by X-ray diffraction, Raman spectroscopy and scanning electron microscopy. Adsorption isotherms of Glyp onto this inorganic lamellar material have been established. Electrocatalytic oxidation of Glyp and Gluf is possible at the Ni{sup 3+} centres of the structure. The electrochemical responses of the NiAl-LDH modified electrode were obtained by cyclic voltammetry and chronoamperometry at 0.49 V/SCE as a function of herbicide concentration in 0.1 M NaOH solution. The electrocatalytic response showed a linear dependence on the Glyp concentration ranging between 0.01 and 0.9 mM with a detection limit of 1 {mu}M and sensitivity 287 mA/M cm{sup 2}. The sensitivity found for Gluf was lower (178 mA/M cm{sup 2}).

  9. Herbicide glufosinate inhibits yeast growth and extends longevity during wine fermentation.

    Science.gov (United States)

    Vallejo, Beatriz; Picazo, Cecilia; Orozco, Helena; Matallana, Emilia; Aranda, Agustín

    2017-09-29

    Glufosinate ammonium (GA) is a widely used herbicide that inhibits glutamine synthetase. This inhibition leads to internal amino acid starvation which, in turn, causes the activation of different nutrient sensing pathways. GA also inhibits the enzyme of the yeast Saccharomyces cerevisiae in such a way that, although it is not used as a fungicide, it may alter yeast performance in industrial processes like winemaking. We describe herein how GA indeed inhibits the yeast growth of a wine strain during the fermentation of grape juice. In turn, GA extends longevity in a variety of growth media. The biochemical analysis indicates that GA partially inhibits the nutrient sensing TORC1 pathway, which may explain these phenotypes. The GCN2 kinase mutant is hypersensitive to GA. Hence the control of translation and amino acid biosynthesis is required to also deal with the damaging effects of this pesticide. A global metabolomics analysis under winemaking conditions indicated that an increase in amino acid and in polyamines occurred. In conclusion, GA affects many different biochemical processes during winemaking, which provides us with some insights into both the effect of this herbicide on yeast physiology and into the relevance of the metabolic step for connecting nitrogen and carbon metabolism.

  10. Metodologia para determinação de efeitos fisiológicos e metabólicos do glufosinate em soja

    OpenAIRE

    Barberis, Luis Rodrigo Miyamoto [UNESP

    2012-01-01

    O glufosinate é derivado do fosfinotricina, uma toxina microbiana natural isolada a partir de duas espécies de fungos Streptomyces. Atua inibindo a atividade da enzima glutamina sintetase, que é necessária para a produção do aminoácido glutamina e para a desintoxicação da amônia pela planta. Objetivou-se neste trabalho avaliar a intoxicação e alterações fisiológicas e bioquímicas causadas pelo glufosinate em plantas de soja. O experimento foi conduzido em casa-de-vegetação, no Núcleo de Pesqu...

  11. Glufosinate herbicide-tolerant (LibertyLink) rice vs. conventional rice in diets for growing-finishing swine.

    Science.gov (United States)

    Cromwell, G L; Henry, B J; Scott, A L; Gerngross, M F; Dusek, D L; Fletcher, D W

    2005-05-01

    Genetically modified (GM) rice (LibertyLink, event LLRICE62) that is tolerant to glufosinate ammonium (Liberty) herbicide was compared with a near-isogenic (NI) conventional medium-grain brown rice (cultivar, Bengal) and a commercially milled long-grain brown rice in diets for growing-finishing pigs. The GM and NI rice were grown in 2000. The GM rice was from fields treated (GM+) or not treated (GM-) with glufosinate herbicide. The GM- and NI rice were grown using herbicide regimens typical of southern United States rice production practices. The four rice grains were similar in composition. Growing-finishing pigs (n = 96) were fed fortified rice-soybean meal diets containing the four different rice grains from 25 to 106 kg BW. Diets contained 0.99% lysine initially (growing phase), with lysine decreased to 0.80% (early finishing phase) and 0.65% (late finishing phase), when pigs reached 51 and 77 kg, respectively. The percentage of rice in the four diets was constant during each of the three phases (72.8, 80.0, and 85.8% for the growing, early-finishing, and late-finishing phases, respectively). There were six pen replicates (three pens of barrows and three pens of gilts) and four pigs per pen for each dietary treatment. All pigs were slaughtered at the termination of the study to collect carcass data. At the end of the 98-d experiment, BW gain, feed intake (as-fed basis), and feed:gain ratio did not differ (P > 0.05) for pigs fed the GM+ vs. conventional rice diets, but growth performance traits of pigs fed the GM+ rice diets were superior (P glufosinate herbicide-tolerant rice was similar in composition and nutritional value to conventional rice for growing-finishing pigs.

  12. Intoxicação e alterações metabólicas do algodão sensível e resistente ao amônio glufosinate

    OpenAIRE

    Latorre, Débora de Oliveira [UNESP

    2014-01-01

    The Liberty Link cotton cultivars are those that resist a dose of ammonium glufosinate application that normally would be recommended for other biotypes species .These cotton plants are constitute genetically with gene that encodes the production of enzyme phosphinothricin acetyl transferase (PAT) responsible for the acetylation of glufosinate ammonium, inactivating it in the plant. The cotton cultivar FiberMax® 975 WideStrike has present in i ts DNA the gene PAT and present intermediate meta...

  13. Determination of the minimal inhibitory concentration of Ammonium glufosinate in organogenic calli of Phaseolus vulgaris cv. `CIAP 7247F'

    OpenAIRE

    Idalmis Bermúdez-Caraballoso; Raúl Collado; Lourdes R. García; Novisel Veitía; Amanda Martirena; Damaris Torres; Carlos Romero; Gert Angenon

    2012-01-01

    An efficient selection system is necessary for distinguishing transformed cells of the untransformed tissue. This study aimed to determine the minimum inhibitory concentration of the herbicide Ammonium glufosinate in organogenic calli of Phaseolus vulgaris cv. CIAP 7247F, to use it as a selective agent in the process of genetic transformation. Fragments (4-5 mm) of proliferated calli after second subculture were used as explant. Callus proliferation medium with different concentrations of Amm...

  14. Persistence and transformation of the herbicide (/sup 14/C)glufosinate-ammonium in prairie soils under laboratory conditions

    Energy Technology Data Exchange (ETDEWEB)

    Smith, A.E.

    The degradation of the herbicide (/sup 14/C)glufosinate-ammonium (the ammonium salt of DL-homoalanin-4-ylmethylphosphinic acid), at a rate of 2 ppm, was studied in three prairie soils at 85% of their field capacity moisture at both 20 and 10/sup 0/C. In all soils the herbicide was biologically transformed to degradation product(s) that underwent further slow degradation with release of (/sup 14/C)carbon dioxide. At 20/sup 0/C, the soil half-life values for the (/sup 14/C)herbicide were 3-7 days and, at 10/sup 0/C, 8-11 days. Over a 90-day incubation period at 20/sup 0/C, between 28 and 55% of the applied radioactivity was released from treated soils as (/sup 14/C)carbon dioxide; solvent-extractable degradation product(s) accounted for 19-37% of the applied radioactivity; between 2.4 and 9.5% of the initial /sup 14/C was incorporated into soil microbial biomass and 7-13% into the fulvic, humic, and humin soil fractions.

  15. [Determination of glufosinate residue in tea by liquid chromatography-tandem mass spectrometry coupled with precolumn derivatization].

    Science.gov (United States)

    Lin, Yonghui; Liu, Zhengcai; Yang, Fang; Qiu, Yuanjin; Liu, Suzhen; Su, Zhijiao; Zhang, Qiong; Xue, Zhimin; Fang, Yu

    2012-12-01

    A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was established for the determination of glufosinate (GLUF) residue in tea. The GLUF was extracted with water for 30 min under ultrasonication, and cleaned-up using a C18 solid phase extraction cartridge, then derived using fluorenylmethylchloroformate (FMOC-Cl) in borate buffer for 2 h. The separation was performed on a Kinetex C18 column with the mobile phases of acetonitrile and 5 mmol/L ammonium acetate aqueous solution (containing 0.2% (v/v) formic acid) in a gradient elution mode. The identification and quantification of the GLUF were carried out by MS/MS in negative electrospray ionization (ESI(-)) and multiple reaction monitoring (MRM) mode, the quantification analysis was performed by external standard method. The calibration curve showed good linearity in the range of 2.5 - 50.0 microg/L with the correlation coefficient r2 > 0.999. The limit of quantification (LOQ) was 0.10 mg/kg. The average recoveries of GLUF spiked at 0.10, 0.50 and 1.00 mg/kg levels in tea were between 61.6% and 81.4%, and the relative standard deviations (RSDs) were between 3.2% and 8.4%. The method is simple, rapid, sensitive, accurate and suitable for the confirmation and quantification of GLUF in tea.

  16. Persistence and transformation of the herbicide [14C]glufosinate-ammonium in prairie soils under laboratory conditions

    International Nuclear Information System (INIS)

    Smith, A.E.

    1988-01-01

    The degradation of the herbicide [ 14 C]glufosinate-ammonium (the ammonium salt of DL-homoalanin-4-ylmethylphosphinic acid), at a rate of 2 ppm, was studied in three prairie soils at 85% of their field capacity moisture at both 20 and 10 0 C. In all soils the herbicide was biologically transformed to degradation product(s) that underwent further slow degradation with release of [ 14 C]carbon dioxide. At 20 0 C, the soil half-life values for the [ 14 C]herbicide were 3-7 days and, at 10 0 C, 8-11 days. Over a 90-day incubation period at 20 0 C, between 28 and 55% of the applied radioactivity was released from treated soils as [ 14 C]carbon dioxide; solvent-extractable degradation product(s) accounted for 19-37% of the applied radioactivity; between 2.4 and 9.5% of the initial 14 C was incorporated into soil microbial biomass and 7-13% into the fulvic, humic, and humin soil fractions

  17. Toxicity of a glufosinate- and several glyphosate-based herbicides to juvenile amphibians from the Southern High Plains, USA.

    Science.gov (United States)

    Dinehart, Simon K; Smith, Loren M; McMurry, Scott T; Anderson, Todd A; Smith, Philip N; Haukos, David A

    2009-01-15

    Pesticide toxicity is often proposed as a contributing factor to the world-wide decline of amphibian populations. We assessed acute toxicity (48 h) of a glufosinate-based herbicide (Ignite 280 SL) and several glyphosate-based herbicide formulations (Roundup WeatherMAX, Roundup Weed and Grass Killer Super Concentrate, Roundup Weed and Grass Killer Ready-To-Use Plus on two species of amphibians housed on soil or moist paper towels. Survival of juvenile Great Plains toads (Bufo cognatus) and New Mexico spadefoots (Spea multiplicata) was reduced by exposure to Roundup Weed and Grass Killer Ready-To-Use Plus on both substrates. Great Plains toad survival was also reduced by exposure to Roundup Weed and Grass Killer Super Concentrate on paper towels. New Mexico spadefoot and Great Plains toad survival was not affected by exposure to the two agricultural herbicides (Roundup WeatherMAX and Ignite 280 SL) on either substrate, suggesting that these herbicides likely do not pose an immediate risk to these species under field conditions.

  18. Sublethal effects of the herbicide glufosinate ammonium on crops and wild plants: short-term effects compared to vegetative recovery and plant reproduction.

    Science.gov (United States)

    Carpenter, David; Boutin, Céline

    2010-10-01

    Current guidelines for phytotoxicity testing rely heavily on short-term testing of primarily crop species to predict the sensitivity of non-target, wild plants to herbicides. However, little is known on how plants recover following initial growth inhibitions in standard 14-28 day greenhouse tests conducted for pesticide assessment and registration. The objectives of this study were to assess the ability of plant species to recover (biomass and reproduction) when tested at the juvenile stage (routine regulatory testing), comparing crop and wild species and using the herbicide glufosinate ammonium. Ten crops and 10 wild species were tested with a one-time exposure to glufosinate ammonium in a greenhouse. Half the plants of each species (9 doses × 6 replicates) were harvested 3 weeks after being sprayed (short-term). The remaining plants were harvested several weeks later, coinciding with seed set or natural senescence (long-term). Total aboveground biomass and several endpoints related to crop production and plant reproduction were measured. Calculated IC50 values (dosage that results in a 50% decrease in the biomass of a plant as compared to the untreated controls) based solely on aboveground biomass, for species harvested in the long-term were generally higher than those obtained in the short-term (with two exceptions), indicating recovery over time. Crop species did not differ from wild species in terms of sensitivity. However, in seven out of 12 cases where reproduction was measurable, reproductive endpoints were more sensitive than either short or long-term biomass endpoints, indicating the importance of examining these parameters in phytotoxicity testing. Glufosinate ammonium was found to be phytotoxic at low doses (2.64-7.74% g ai/ha of the label rate).

  19. A review of methods for the analysis of orphan and difficult pesticides: glyphosate, glufosinate, quaternary ammonium and phenoxy acid herbicides, and dithiocarbamate and phthalimide fungicides.

    Science.gov (United States)

    Raina-Fulton, Renata

    2014-01-01

    This article reviews the chromatography/MS methodologies for analysis of pesticide residues of orphan and difficult chemical classes in a variety of sample matrixes including water, urine, blood, and food. The review focuses on pesticide classes that are not commonly included in multiresidue analysis methods such as highly polar or ionic herbicides including glyphosate, glufosinate, quaternary ammonium, and phenoxy acid herbicides, and some of their major degradation or metabolite products. In addition, dithiocarbamate and phthalimide fungicides, which are thermally unstable and have stability issues in some solvents or sample matrixes, are also examined due to their special needs in residue analysis.

  20. Sensibilidade de indivíduos e progênies de bidens pilosa e conyza sumatrensis ao amônio glufosinate

    OpenAIRE

    Brito, Ivana Paula Ferraz Santos de [UNESP

    2016-01-01

    A sensibilidade de plantas daninhas a herbicidas frequentemente se apresenta variável, em função de diversos fatores. O herbicida amônio glufosinate tem ação de contato e inibe a atividade da enzima glutamina sintetase, causando dentre outros efeitos, o acúmulo de amônia nos tecidos foliares, sendo esse um bom indicativo da intoxicação das plantas. Desse modo, o objetivo desse trabalho foi identificar a resposta de plantas de Bidens pilosa e Conyza sumatrensis a diferentes doses do herbicida ...

  1. MRI characterization of structural mouse brain changes in response to chronic exposure to the glufosinate ammonium herbicide.

    Science.gov (United States)

    Meme, Sandra; Calas, André-Guilhem; Montécot, Céline; Richard, Oliver; Gautier, Hélène; Gefflaut, Thierry; Doan, Bich Thuy; Même, William; Pichon, Jacques; Beloeil, Jean-Claude

    2009-10-01

    Glufosinate ammonium (GLA) is the active component of herbicides widely used in agriculture, truck farming, or public domains. GLA acts by inhibiting the plant glutamine synthetase (GlnS). It also inhibits mammalian GlnS in vitro and ex vivo. In the central nervous system this enzyme is exclusively localized in glial cells. Whereas acute neurotoxic effects of GLA are well documented, long-term effects during chronic exposure at low doses remain largely undisclosed. In the present work, C57BL/6J mice were treated intraperitoneally with 2.5, 5, and 10 mg/kg of GLA three times a week during 10 weeks. Cerebral magnetic resonance imaging (MRI) experiments were performed at high field (9.4 T) and the images were analyzed with four texture analysis (TA) methods. TA highlighted structural changes in seven brain structures after chronic GLA treatments. Changes are dose dependent and can be seen at a dose as low as 2.5 mg/kg for two areas, namely hippocampus and somatosensorial cortex. Glial fibrillary acidic protein (GFAP) expression in the same seven brain structures and GlnS activity in the hippocampus and cortex areas were also studied. The number of GFAP-positive cells is modified in six out of the seven areas examined. GlnS activity was significantly increased in the hippocampus but not in the cortex. These results indicate some kind of suffering at the cerebral level after chronic GLA treatment. Changes in TA were compared with the modification of the number of GFAP-positive astrocytes in the studied brain areas after GLA treatment. We show that the noninvasive MRI-TA is a sensitive method and we suggest that it would be a very helpful tool that can efficiently contribute to the detection of cerebral alterations in vivo during chronic exposure to xenobiotics.

  2. Molecular investigations of the soil, rhizosphere and transgenic glufosinate-resistant rape and maize plants in combination with herbicide (Basta) application under field conditions.

    Science.gov (United States)

    Ernst, Dieter; Rosenbrock-Krestel, Hilkea; Kirchhof, Gudrun; Bieber, Evi; Giunaschwili, Nathela; Müller, Rüdiger; Fischbeck, Gerhard; Wagner, Tobias; Sandermann, Heinrich; Hartmann, Anton

    2008-01-01

    A field study was conducted during 1994 to 1998 on the Experimental Farm Roggenstein, near Fürstenfeldbruck, Bavaria, Germany to determine the effect of transgenic glufosinate-resistant rape in combination with the herbicide Basta [glufosinate-ammonium, phosphinothricin, ammonium (2RS)-2-amino-4-(methylphosphinato) butyric acid] application on soil microorganisms and the behaviour of the synthetic transgenic DNA in response to normal agricultural practice. No influence of Basta on microbial biomass could be detected. The phospholipid fatty acid analysis of soil extracts showed no difference between Basta application and mechanical weed control, whereas conventional herbicide application revealed a different pattern. Basta application resulted in a changed population of weeds with a selective effect for Viola arvensis. During senescence, transgenic rape DNA was degraded similar to endogenous control DNA. After ploughing the chopped plant material in the soil, transgenic as well as endogenous control DNA sequences could be detected for up to 4 weeks for rape and up to 7 months for maize, whereas PCR analysis of composted transgenic maize revealed the presence of the transgene over a period of 22 months.

  3. Determination of Glyphosate, its Degradation Product Aminomethylphosphonic Acid, and Glufosinate, in Water by Isotope Dilution and Online Solid-Phase Extraction and Liquid Chromatography/Tandem Mass Spectrometry

    Science.gov (United States)

    Meyer, Michael T.; Loftin, Keith A.; Lee, Edward A.; Hinshaw, Gary H.; Dietze, Julie E.; Scribner, Elisabeth A.

    2009-01-01

    The U.S. Geological Survey method (0-2141-09) presented is approved for the determination of glyphosate, its degradation product aminomethylphosphonic acid (AMPA), and glufosinate in water. It was was validated to demonstrate the method detection levels (MDL), compare isotope dilution to standard addition, and evaluate method and compound stability. The original method USGS analytical method 0-2136-01 was developed using liquid chromatography/mass spectrometry and quantitation by standard addition. Lower method detection levels and increased specificity were achieved in the modified method, 0-2141-09, by using liquid chromatography/tandem mass spectrometry (LC/MS/MS). The use of isotope dilution for glyphosate and AMPA and pseudo isotope dilution of glufosinate in place of standard addition was evaluated. Stable-isotope labeled AMPA and glyphosate were used as the isotope dilution standards. In addition, the stability of glyphosate and AMPA was studied in raw filtered and derivatized water samples. The stable-isotope labeled glyphosate and AMPA standards were added to each water sample and the samples then derivatized with 9-fluorenylmethylchloroformate. After derivatization, samples were concentrated using automated online solid-phase extraction (SPE) followed by elution in-line with the LC mobile phase; the compounds separated and then were analyzed by LC/MS/MS using electrospray ionization in negative-ion mode with multiple-reaction monitoring. The deprotonated derivatized parent molecule and two daughter-ion transition pairs were identified and optimized for glyphosate, AMPA, glufosinate, and the glyphosate and AMPA stable-isotope labeled internal standards. Quantitative comparison between standard addition and isotope dilution was conducted using 473 samples analyzed between April 2004 and June 2006. The mean percent difference and relative standard deviation between the two quantitation methods was 7.6 plus or minus 6.30 (n = 179), AMPA 9.6 plus or minus 8

  4. Cardiovascular effects of a herbicide containing glufosinate and a surfactant: in vitro and in vivo analyses in rats.

    Science.gov (United States)

    Koyama, K; Koyama, K; Goto, K

    1997-08-01

    A herbicide, Basta (BASTA), containing glufosinate ammonium (GLA) as the main component and an anionic surfactant, sodium polyoxyethylene alkylether sulfate (AES), causes hemodynamic changes characterized by a decrease in total vascular resistance with an increase or a decrease in cardiac output in human acute oral poisoning. With a motivation based on these clinical observations, we tried to elucidate the exact component and its mode of action that is mostly responsible for the direct cardiovascular effects of this herbicide formulation, investigating the effects of BASTA, GLA, and AES independently on the cardiovascular system in rats in vitro and in vivo. In isolated right atria beating spontaneously in Krebs-Ringer's solution, BASTA and AES produced negative chronotropic responses in a concentration-dependent manner. In electrically driven isolated left atria, BASTA and AES produced positive inotropic responses concentration dependently but negative inotropic responses at extremely high concentrations. In aortic ring segments, BASTA and AES produced no vasoconstrictive effects but exerted significant vasodilative effects when the aortic ring was precontracted with phenylephrine. These in vitro responses caused by BASTA and AES occurred to a similar degree. On the other hand, the main component, GLA, produced no effects in isolated atria and aortas. In anesthetized rats, relatively low doses of BASTA and AES produced a decrease in blood pressure followed by a slight increase in heart rate, which was presumably due to baroreflex caused by the decrease in blood pressure. At an extremely high dose, BASTA and AES produced a decrease in blood pressure with a marked decrease in heart rate. These in vivo responses to BASTA and AES also occurred to a similar degree. In contrast, the main component, GLA, did not produce any effects on heart rate and blood pressure in anesthetized rats. From these results, we concluded that the effects of BASTA in our in vivo experiments

  5. Integrated Palmer Amaranth Management in Glufosinate-Resistant Cotton: I. Soil-Inversion, High-Residue Cover Crops and Herbicide Regimes

    Directory of Open Access Journals (Sweden)

    Michael G. Patterson

    2012-11-01

    Full Text Available A three year field experiment was conducted to evaluate the role of soil-inversion, cover crops and herbicide regimes for Palmer amaranth between-row (BR and within-row (WR management in glufosinate-resistant cotton. The main plots were two soil-inversion treatments: fall inversion tillage (IT and non-inversion tillage (NIT. The subplots were three cover crop treatments: crimson clover, cereal rye and winter fallow; and sub subplots were four herbicide regimes: preemergence (PRE alone, postemergence (POST alone, PRE + POST and a no herbicide check (None. The PRE herbicide regime consisted of a single application of pendimethalin at 0.84 kg ae ha−1 plus fomesafen at 0.28 kg ai ha−1. The POST herbicide regime consisted of a single application of glufosinate at 0.60 kg ai ha−1 plus S-metolachlor at 0.54 kg ai ha−1 and the PRE + POST regime combined the prior two components. At 2 weeks after planting (WAP cotton, Palmer amaranth densities, both BR and WR, were reduced ≥90% following all cover crop treatments in the IT. In the NIT, crimson clover reduced Palmer amaranth densities >65% and 50% compared to winter fallow and cereal rye covers, respectively. At 6 WAP, the PRE and PRE + POST herbicide regimes in both IT and NIT reduced BR and WR Palmer amaranth densities >96% over the three years. Additionally, the BR density was reduced ≥59% in no-herbicide (None following either cereal rye or crimson clover when compared to no-herbicide in the winter fallow. In IT, PRE, POST and PRE + POST herbicide regimes controlled Palmer amaranth >95% 6 WAP. In NIT, Palmer amaranth was controlled ≥79% in PRE and ≥95% in PRE + POST herbicide regimes over three years. POST herbicide regime following NIT was not very consistent. Averaged across three years, Palmer amaranth controlled ≥94% in PRE and PRE + POST herbicide regimes regardless of cover crop. Herbicide regime effect on cotton yield was highly significant; the maximum cotton yield was

  6. Pathogen intelligence

    Directory of Open Access Journals (Sweden)

    Michael eSteinert

    2014-01-01

    Full Text Available Different species inhabit different sensory worlds and thus have evolved diverse means of processing information, learning and memory. In the escalated arms race with host defense, each pathogenic bacterium not only has evolved its individual cellular sensing and behaviour, but also collective sensing, interbacterial communication, distributed information processing, joint decision making, dissociative behaviour, and the phenotypic and genotypic heterogeneity necessary for epidemiologic success. Moreover, pathogenic populations take advantage of dormancy strategies and rapid evolutionary speed, which allow them to save co-generated intelligent traits in a collective genomic memory. This review discusses how these mechanisms add further levels of complexity to bacterial pathogenicity and transmission, and how mining for these mechanisms could help to develop new anti-infective strategies.

  7. Foodborne pathogens

    Directory of Open Access Journals (Sweden)

    Thomas Bintsis

    2017-06-01

    Full Text Available Foodborne pathogens are causing a great number of diseases with significant effects on human health and economy. The characteristics of the most common pathogenic bacteria (Bacillus cereus, Campylobacter jejuni, Clostridium botulinum, Clostridium perfringens, Cronobacter sakazakii, Esherichia coli, Listeria monocytogenes, Salmonella spp., Shigella spp., Staphylococccus aureus, Vibrio spp. and Yersinia enterocolitica, viruses (Hepatitis A and Noroviruses and parasites (Cyclospora cayetanensis, Toxoplasma gondii and Trichinella spiralis, together with some important outbreaks, are reviewed. Food safety management systems based on to classical hazard-based approach has been proved to be inefficient, and risk-based food safety approach is now suggested from leading researchers and organizations. In this context, a food safety management system should be designed in a way to estimate the risks to human health from food consumption and to identify, select and implement mitigation strategies in order to control and reduce these risks. In addition, the application of suitable food safety education programs for all involved people in the production and consumption of foods is suggested.

  8. Safety evaluation of the phosphinothricin acetyltransferase proteins encoded by the pat and bar sequences that confer tolerance to glufosinate-ammonium herbicide in transgenic plants.

    Science.gov (United States)

    Hérouet, Corinne; Esdaile, David J; Mallyon, Bryan A; Debruyne, Eric; Schulz, Arno; Currier, Thomas; Hendrickx, Koen; van der Klis, Robert-Jan; Rouan, Dominique

    2005-03-01

    Transgenic plant varieties, which are tolerant to glufosinate-ammonium, were developed. The herbicide tolerance is based upon the presence of either the bar or the pat gene, which encode for two homologous phosphinothricin acetyltransferases (PAT), in the plant genome. Based on both a review of published literature and experimental studies, the safety assessment reviews the first step of a two-step-approach for the evaluation of the safety of the proteins expressed in plants. It can be used to support the safety of food or feed products derived from any crop that contains and expresses these PAT proteins. The safety evaluation supports the conclusion that the genes and the donor microorganisms (Streptomyces) are innocuous. The PAT enzymes are highly specific and do not possess the characteristics associated with food toxins or allergens, i.e., they have no sequence homology with any known allergens or toxins, they have no N-glycosylation sites, they are rapidly degraded in gastric and intestinal fluids, and they are devoid of adverse effects in mice after intravenous administration at a high dose level. In conclusion, there is a reasonable certainty of no harm resulting from the inclusion of the PAT proteins in human food or in animal feed.

  9. [Establisment of a genetic transformation method of coffee (Coffea arabica cv. Catimor) and incorporation of bar gene for ammonium glufosinate resistance].

    Science.gov (United States)

    Fernández Da Silva, Rafael

    2003-01-01

    In order to establish a successful method of genetic transformation in Coffea arabica cv. Catimor, different conditions of generation and electroporation were evaluated on different plant tissues. Cell suspension system was improved using one hormone only (BA), obtaining high yields of primary and secondary somatic embryo production. For selection of viable and potentially transformed cells, MTT (1%) method and ammonium glufosinate concentration (1 mg/L in leaf, callus and embryos; and 5 mg/L in cells) were established. Different conditions were evaluated to electroporate different explants (embryogenic callus, vitroplants leaves, globular and torpedo embryos). The highest gus gene expression percentage by explant were found on enzymatic treated tissues at 375 V/cm in callus, and at 625 V/cm in leaves and embryos. Torpedo embryos cultured on liquid medium were the only type of tissue that could regenerate into plants, where secondary somatic embryos were obtained. Those embryos were positive to the gus gene histochemical test and to the gus and bar genes amplification on a PCR reaction.

  10. Evaluation of the effects and mechanisms of action of glufosinate, an organophosphate insecticide, on striatal dopamine release by using in vivo microdialysis in freely moving rats.

    Science.gov (United States)

    Ferreira Nunes, Brenda V; Durán, Rafael; Alfonso, Miguel; de Oliveira, Iris Machado; Ferreira Faro, Lilian R

    2010-10-01

    The purpose of the present work was to assess the effects of glufosinate ammonium (GLA), an aminoacid structurally related to glutamate, on in vivo dopamine (DA) release from rat striatum, using brain microdialysis coupled to HPLC-EC. Intrastriatal administration of GLA produced significant concentration-dependent increases in DA levels. At least two mechanisms can be proposed to explain these increases: GLA could be inducing DA release from synaptic vesicles or producing an inhibition of DA transporter (DAT). Thus, we investigated the effects of GLA under Ca(++)-free condition, and after pretreatment with reserpine and TTX. It was observed that the pretreatment with Ca(++)-free Ringer, reserpine or TTX significantly reduced the DA release induced by GLA. Coinfusion of GLA and nomifensine shows that the GLA-induced DA release did not involve the DAT. These results show that GLA-induced striatal DA release is probably mediated by an exocytotic-, Ca(++)-, action potential-dependent mechanism, being independent of DAT.

  11. Degradation and leaching behaviour of 14C-glufosinate in a silty sand soil. Experiments in outdoor lysimeters with undisturbed soil cores

    International Nuclear Information System (INIS)

    Kubiak, R.

    1996-12-01

    Degradation and leaching behaviour of 14 C-labelled glufosinate in a silty sand soil was investigated in two outdoor lysimeters after repeated application of 12.5 litres/hectare (1/ha) Basta (divided in 7.5 and 5 l/ha respectively). The 14 C-loss during application was 4.8-8.2%. The 14 C-content in the plants (vines and weeds) was 0.3% of that applied at the most. After 130 days, 25.9 and 25.5% of the applied material was found in the soil up to a depth of 40 cm. One year after the first application, this amount was still 18.5 and 18.6%. As a consequence of the renewed spraying, the detected amounts of 14 C were 44.3 and 43.1% some 107 days after the first application in the second experimental year. The additional investigation in lysimeter 2 after 373 days showed a decrease to 33.9%. Most of the detected radioactivity remained in the 0-10 cm soil layer. At the end of the experiment, the amount of 14 C in the 30-40 cm layer was 0.5%. The total residues in the 0-10 cm soil layer were less than 1 mg/kg at all dates of sampling, and only a small amount still represented the free acid of the active ingredient. The average values were 0.05 mg/kg after 130 days, 0.01 mg/kg after 363 days and 0.09 mg/kg at the following date of sampling. In the spring of the following year, no residues of the free acid were detectable. The radioactivity in the percolate amounted to a maximum of 0.11% of that applied and in no case represented the free acid of the ammonium salt. (author)

  12. [Simultaneous determination of glyphosate and glufosinate-ammonium residues in tea by ultra performance liquid chromatography-tandem mass spectrometry coupled with pre-column derivatization].

    Science.gov (United States)

    Wu, Xiaogang; Chen, Xiaoquan; Xiao, Haijun; Liu, Binqiu

    2015-10-01

    A method was developed for the determination of glyphosate (GLY) and glufosinate-ammonium (GLUF) in tea using ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The sample was extracted with ultrapure water and dichloromethane for 30 min under ultrasonication, followed by a simple cleanup with a C18 solid phase extraction (SPE) cartridge, and then GLY and GLUF were derivatized using 9-fluorenylmethoxycarbonyl (FMOC-Cl) in borate buffer for 2 h. The derivatives of GLY and GLUF were separated on a Waters C18 column (50 mm x 2.1 mm, 1.7 μm) in a gradient elution mode, and finally detected with positive electrospray ionization-mass spectrometry (ESI-MS/MS ) in multiple reaction monitoring (MRM) mode. The quantification analysis was performed by external standard method. The method showed a good linearity (r > 0. 990) in the range of 0.003 125-0.1 mg/L. The limits of detection (LODs) of GLY and GLUF were 0.03 mg/kg. At the spiked levels of 0.375, 1.5 and 4.5 mg/kg, the recoveries of GLY and GLUF were 87.37%-99.11% and 81.44% -86.17% respectively, and the relative standard deviations (RSDs) (n = 6) of GLY and GLUF were 0.68%-1.35% and 1.01%-2.33%, respectively. This method is simple, rapid and characterized with acceptable sensitivity and accuracy to meet the requirements for the analysis of GLY and GLUF simultaneously in tea.

  13. Role of glutamate receptors and nitric oxide on the effects of glufosinate ammonium, an organophosphate pesticide, on in vivo dopamine release in rat striatum.

    Science.gov (United States)

    Faro, Lilian R F; Ferreira Nunes, Brenda V; Alfonso, Miguel; Ferreira, Vania M; Durán, Rafael

    2013-09-15

    The purpose of the present work was to assess the possible role of glutamatergic receptors and nitric oxide (NO) production on effects of glufosinate ammonium (GLA), an organophosphate pesticide structurally related to glutamate, on in vivo striatal dopamine release in awake and freely moving rats. For this, we used antagonists of NMDA (MK-801 and AP5) or AMPA/kainate (CNQX) receptors, or nitric oxide synthase (NOS) inhibitors (l-NAME and 7-NI), to study the effects of GLA on release of dopamine from rat striatum. So, intrastriatal infusion of 10mM GLA significantly increased dopamine levels (1035±140%, compared with basal levels) and administration of GLA to MK-801 (250μM) or AP5 (650μM) pretreated animals, produced increases in dopamine overflow that were ∼40% and ∼90% smaller than those observed in animals not pretreated with MK-801 or AP5. Administration of GLA to CNQX (500μM) pretreated animals produced an effect that was not significantly different from the one produced in animals not pretreated with CNQX. On the other hand, administration of GLA to l-NAME (100μM) or 7-NI (100μM) pretreated animals, produced increases in dopamine overflow that were ∼80% and ∼75% smaller than those observed in animals not pretreated with these inhibitors. In summary, GLA appears to act, at least in part, through an overstimulation of NMDA (and not AMPA/kainate) receptors with possible NO production to induce in vivo dopamine release. Administration of NMDA receptor antagonists and NOS inhibitors partially blocks the release of dopamine from rat striatum. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  14. Degradation and leaching behaviour of {sup 14}C-glufosinate in a silty sand soil. Experiments in outdoor lysimeters with undisturbed soil cores

    Energy Technology Data Exchange (ETDEWEB)

    Kubiak, R

    1996-12-01

    Degradation and leaching behaviour of {sup 14}C-labelled glufosinate in a silty sand soil was investigated in two outdoor lysimeters after repeated application of 12.5 litres/hectare (1/ha) Basta (divided in 7.5 and 5 l/ha respectively). The {sup 14}C-loss during application was 4.8-8.2%. The {sup 14}C-content in the plants (vines and weeds) was 0.3% of that applied at the most. After 130 days, 25.9 and 25.5% of the applied material was found in the soil up to a depth of 40 cm. One year after the first application, this amount was still 18.5 and 18.6%. As a consequence of the renewed spraying, the detected amounts of {sup 14}C were 44.3 and 43.1% some 107 days after the first application in the second experimental year. The additional investigation in lysimeter 2 after 373 days showed a decrease to 33.9%. Most of the detected radioactivity remained in the 0-10 cm soil layer. At the end of the experiment, the amount of {sup 14}C in the 30-40 cm layer was 0.5%. The total residues in the 0-10 cm soil layer were less than 1 mg/kg at all dates of sampling, and only a small amount still represented the free acid of the active ingredient. The average values were 0.05 mg/kg after 130 days, 0.01 mg/kg after 363 days and 0.09 mg/kg at the following date of sampling. In the spring of the following year, no residues of the free acid were detectable. The radioactivity in the percolate amounted to a maximum of 0.11% of that applied and in no case represented the free acid of the ammonium salt. (author)

  15. Induction of micronuclei and nuclear abnormalities in tadpoles of the common toad (Rhinella arenarum) treated with the herbicides Liberty® and glufosinate-ammonium.

    Science.gov (United States)

    Lajmanovich, Rafael C; Cabagna-Zenklusen, Mariana C; Attademo, Andrés M; Junges, Celina M; Peltzer, Paola M; Bassó, Agustín; Lorenzatti, Eduardo

    2014-07-15

    The assessment of micronucleated erythrocytes (ME) in blood represents a widely used method for the detection of chromosomal damage by chemical agents, such as herbicides that may occur as water contaminants. We investigated the changes in some circulating blood-cell parameters of tadpoles of the common toad (Rhinella arenarum) that were exposed during 48 or 96 h to three sub-lethal concentrations (3.75, 7.5, and 15 mg/L) of a commercial formulation of a glufosinate-ammonium (GLA)-based herbicide (Liberty(®), LY(®)) as well as to the corresponding active ingredient GLA. The frequency of ME and other erythrocyte nuclear abnormalities (ENA, i.e., lobed nuclei, binucleates or segmented nuclei, kidney-shaped nuclei, notched nuclei, and picnotic nuclei) were evaluated and compared with positive (cyclophosphamide, CP, 40 mg/L) and negative (de-chlorinated tap water) controls. The results indicate that the exposure of R. arenarum tadpoles to LY(®) induces a concentration-dependent increase in ME frequency. The ENA frequency at 48 h was also significantly higher than that in the negative control group for all the chemicals assayed (CP, LY(®) and GLA) whereas at 96 h, increases in ENA over the negative control group were found only for CP and GLA (7.5 mg/L). Our study demonstrates that the commercial formulation of a GLA-based herbicide induces micronucleus formation in R. arenarum tadpoles, in contrast to the active ingredient. According to these results, the inert ingredients of the commercial formulation played an important role in the production of genotoxic damage in erythrocytes of amphibian tadpoles. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Optimisation of tomato Micro-tom regeneration and selection on glufosinate/Basta and dependency of gene silencing on transgene copy number.

    Science.gov (United States)

    Khuong, Thi Thu Huong; Crété, Patrice; Robaglia, Christophe; Caffarri, Stefano

    2013-09-01

    An efficient protocol of transformation and selection of transgenic lines of Micro-tom, a widespread model cultivar for tomato, is reported. RNA interference silencing efficiency and stability have been investigated and correlated with the number of insertions. Given its small size and ease of cultivation, the tomato (Solanum lycopersicon) cultivar Micro-tom is of widespread use as a model tomato plant. To create and screen transgenic plants, different selectable markers are commonly used. The bar marker carrying the resistance to the herbicide glufosinate/Basta, has many advantages, but it has been little utilised and with low efficiency for identification of tomato transgenic plants. Here we describe a procedure for accurate selection of transgenic Micro-tom both in vitro and in soil. Immunoblot, Southern blot and phenotypic analyses showed that 100 % of herbicide-resistant plants were transgenic. In addition, regeneration improvement has been obtained by using 2 mg/l Gibberellic acid in the shoot elongation medium; rooting optimisation on medium containing 1 mg/l IAA allowed up to 97 % of shoots developing strong and very healthy roots after only 10 days. Stable transformation frequency by infection of leaf explants with Agrobacterium reached 12 %. Shoots have been induced by combination of 1 mg/l zeatin-trans and 0.1 mg/l IAA. Somatic embryogenesis of cotyledon on medium containing 1 mg/l zeatin + 2 mg/l IAA is described in Micro-tom. The photosynthetic psbS gene has been used as reporter gene for RNA silencing studies. The efficiency of gene silencing has been found equivalent using three different target gene fragments of 519, 398 and 328 bp. Interestingly, silencing efficiency decreased from T0 to the T3 generation in plants containing multiple copies of the inserted T-DNA, while it was stable in plants containing a single insertion.

  17. Emerging Pathogens Initiative (EPI)

    Data.gov (United States)

    Department of Veterans Affairs — The Emerging Pathogens Initiative (EPI) database contains emerging pathogens information from the local Veterans Affairs Medical Centers (VAMCs). The EPI software...

  18. Determination of glufosinate ammonium and its metabolite (AE F064619 and AE F061517) residues in water by gas chromatography with tandem mass spectrometry after ion exchange cleanup and derivatization.

    Science.gov (United States)

    Royer, A; Beguin, S; Sochor, H; Communal, P Y

    2000-11-01

    An analytical method for the determination of glufosinate ammonium and its principal metabolites, AE F064619 and AE F061517, in water of two different hardnesses (5 and 30 DH, French hardness) has been developed and validated. Samples were spiked at different levels (0. 05 and 0.5 microgram/L) and were purified by column chromatography on ion-exchange resins. After derivatization with glacial acetic acid and trimethylarthoacetate mixture, the derivatives were quantified by using capillary gas chromatography with an ion-trap tandem mass spectrometric detector. Analytical conditions for MS/MS detection were optimized, and the quantification was carried out on the areas of the most representative ions. The limit of quantification was validated at 0.05 microgram/L for each compound. The mean recovery value and the relative standard deviation (n = 20) were 92.0% and 17. 8% for glufosinate ammonium, 90.2% and 15.8% for AE F064619, and 89. 7% and 12.7% for AE F061517.

  19. Produção de prolina e suscetibilidade ao glufosinato de amônio em plantas transgênicas de citrumelo Swingle Proline production by transgenic plants of Swingle citrumelo and susceptibility to glufosinate ammonium

    Directory of Open Access Journals (Sweden)

    Cristine Elizabeth Alvarenga Carneiro

    2006-05-01

    Full Text Available O objetivo deste trabalho foi avaliar a sensibilidade de plantas transgênicas de citrumelo Swingle com elevada produção de prolina, ao herbicida glufosinato de amônio. As plantas utilizadas apresentavam a inserção do gene mutante da enzima delta1-pirrolina-5-carboxilato sintetase (P5CS, responsável pela biossíntese de prolina. A expressão do gene p5cs em plantas transgênicas causou aumento nas quantidades de prolina em tecidos foliares, em até cinco vezes, quando comparadas às plantas-controle tratadas com 200 µM de glufosinato de amônio. As plantas transgênicas acumularam maior quantidade de NH4+ nas folhas, em relação às plantas não-transgênicas. Os danos causados pelo herbicida foram avaliados in vitro, utilizando-se discos foliares cultivados em meio MS com diferentes concentrações de glufosinato de amônio. Observou-se maior clorose em discos foliares das plantas transgênicas, o que comprova a maior suscetibilidade de plantas de citrumelo Swingle com alta produção de prolina ao herbicida.The objective of this work was to evaluate the susceptibility to glufosinate ammonium of transgenic plants of Swingle citrumelo with high proline production. The mutant gene of the enzyme delta1-pyrroline-5-carboxylate synthetase (P5CS, the rate-limiting enzyme in proline biosynthesis, was inserted into Swingle citrumelo plants. The expression of the gene p5cs caused up to 5-fold increase on the proline content in leaf tissues of transgenic plants treated with 200 µM glufosinate ammonium, when compared with control plants. Leaves of transgenic plants accumulated higher amounts of NH4+ than the nontransgenic control. The herbicide toxicity was evaluated using leaf disks cultivated in MS medium, containing different concentrations of glufosinate ammonium. The severity of the chlorosis, observed in leaf disks of transgenic plants, confirmed the higher susceptibility of Swingle citrumelo plants, with high proline production, to this

  20. AMPK in Pathogens

    OpenAIRE

    Mesquita, Inês Morais; Moreira, Diana; Marques, Belém Sampaio; Laforge, Mireille; Cordeiro-da-Silva, Anabela; Ludovico, Paula; Estaquier, Jérôme; Silvestre, Ricardo Jorge Leal

    2016-01-01

    During host–pathogen interactions, a complex web of events is crucial for the outcome of infection. Pathogen recognition triggers powerful cellular signaling events that is translated into the induction and maintenance of innate and adaptive host immunity against infection. In opposition, pathogens employ active mechanisms to manipulate host cell regulatory pathways toward their proliferation and survival. Among these, subversion of host cell energy metabolism by pathogens is currently recogn...

  1. AMPK in Pathogens.

    Science.gov (United States)

    Mesquita, Inês; Moreira, Diana; Sampaio-Marques, Belém; Laforge, Mireille; Cordeiro-da-Silva, Anabela; Ludovico, Paula; Estaquier, Jérôme; Silvestre, Ricardo

    2016-01-01

    During host-pathogen interactions, a complex web of events is crucial for the outcome of infection. Pathogen recognition triggers powerful cellular signaling events that is translated into the induction and maintenance of innate and adaptive host immunity against infection. In opposition, pathogens employ active mechanisms to manipulate host cell regulatory pathways toward their proliferation and survival. Among these, subversion of host cell energy metabolism by pathogens is currently recognized to play an important role in microbial growth and persistence. Extensive studies have documented the role of AMP-activated protein kinase (AMPK) signaling, a central cellular hub involved in the regulation of energy homeostasis, in host-pathogen interactions. Here, we highlight the most recent advances detailing how pathogens hijack cellular metabolism by suppressing or increasing the activity of the host energy sensor AMPK. We also address the role of lower eukaryote AMPK orthologues in the adaptive process to the host microenvironment and their contribution for pathogen survival, differentiation, and growth. Finally, we review the effects of pharmacological or genetic AMPK modulation on pathogen growth and persistence.

  2. Potatoes, pathogens and pests

    NARCIS (Netherlands)

    Lazebnik, Jenny

    2017-01-01

    Currently, fungicides are necessary to protect potato crops against late blight, Phytophthora infestans, one of the world’s most damaging crop pathogens. The introgression of plant resistance genes from wild potato species targeted specifically to the late blight pathogen into

  3. Food-borne pathogens

    International Nuclear Information System (INIS)

    Niemand, J.G.

    1985-01-01

    The Salmonella scare reinforced the importance of never taking chances when it comes to controlling pathogens. The issue has been resolved by radurisation. The article deals with the various pathogens that can effect food and argues the case for radurisation in dealing with them. It also looks at some of the other food products that can be treated using this process

  4. Pathogen inactivation techniques.

    Science.gov (United States)

    Pelletier, J P R; Transue, S; Snyder, E L

    2006-01-01

    The desire to rid the blood supply of pathogens of all types has led to the development of many technologies aimed at the same goal--eradication of the pathogen(s) without harming the blood cells or generating toxic chemical agents. This is a very ambitious goal, and one that has yet to be achieved. One approach is to shun the 'one size fits all' concept and to target pathogen-reduction agents at the Individual component types. This permits the development of technologies that might be compatible with, for example, plasma products but that would be cytocidal and thus incompatible with platelet concentrates or red blood cell units. The technologies to be discussed include solvent detergent and methylene blue treatments--designed to inactivate plasma components and derivatives; psoralens (S-59--amotosalen) designed to pathogen-reduce units of platelets; and two products aimed at red blood cells, S-303 (a Frale--frangible anchor-linker effector compound) and Inactine (a binary ethyleneimine). A final pathogen-reduction material that might actually allow one material to inactivate all three blood components--riboflavin (vitamin B2)--is also under development. The sites of action of the amotosalen (S-59), the S-303 Frale, Inactine, and riboflavin are all localized in the nucleic acid part of the pathogen. Solvent detergent materials act by dissolving the plasma envelope, thus compromising the integrity of the pathogen membrane and rendering it non-infectious. By disrupting the pathogen's ability to replicate or survive, its infectivity is removed. The degree to which bacteria and viruses are affected by a particular pathogen-reducing technology relates to its Gram-positive or Gram-negative status, to the sporulation characteristics for bacteria, and the presence of lipid or protein envelopes for viruses. Concerns related to photoproducts and other breakdown products of these technologies remain, and the toxicology of pathogen-reduction treatments is a major ongoing area

  5. Potencial de cruzamento natural entre o arroz transgênico resistente ao herbicida glufosinato de amônio e o arroz daninho Outcrossing potential of glufosinate-resistant rice to red rice

    Directory of Open Access Journals (Sweden)

    J.A. Noldin

    2002-08-01

    Full Text Available A utilização de cultivares de arroz irrigado resistentes a herbicidas não-seletivos, como o glufosinato de amônio, pode se constituir numa alternativa de controle de arroz daninho em lavouras de arroz irrigado. O objetivo deste trabalho foi avaliar a taxa e o sentido do cruzamento natural entre plantas de uma linhagem modificada geneticamente para resistência ao herbicida glufosinato de amônio (arroz GM e ao arroz daninho. A taxa de cruzamento natural entre o arroz GM como receptor feminino e o arroz daninho como doador de pólen foi de 0,22 e 0,02%, respectivamente para os ecótipos de arroz daninho com glumas de cor palha e com glumas pretas. No caso inverso, quando o arroz daninho foi o receptor feminino e o arroz GM o doador de pólen, a taxa de cruzamento foi de 0,26 e 0,14%, para o arroz daninho com glumas palha e com glumas pretas, respectivamente. Os resultados deste estudo evidenciaram que ocorreu cruzamento natural entre o arroz GM e o arroz daninho em percentuais que variaram de 0,14 e 0,48%, respectivamente para o arroz preto e para o arroz vermelho. A fim de minimizar a possibilidade de hibridação, medidas de controle eficientes devem ser adotadas no sentido de prevenir a coincidência de floração das plantas de arroz daninho com a das plantas de arroz GM cultivado.The broad spectrum non-selective herbicide ammonium glufosinate, combined with genetically modified glufosinate-resistant rice cultivars (GM rice, may comprise a rice weed control system for red rice and other weeds that infest Brazilian rice fields. The objective of this study was to evaluate the potential for outcrossing and gene flow of GM rice to red rice. Natural outcrossing between adjacent field plots (1 m x 1 m was measured during the 1999/2000 production season in Brazil. The outcrossing rate of the GM rice as the female parent to red rice, as the pollen donor, was 0.22% for strawhull and 0.02% for the blackhull red rice, respectively. In the reciprocal

  6. Processes for managing pathogens.

    Science.gov (United States)

    Godfree, Alan; Farrell, Joseph

    2005-01-01

    Wastewater contains human, animal, and plant pathogens capable of causing viral, bacterial, or parasitic infections. There are several routes whereby sewage pathogens may affect human health, including direct contact, contamination of food crops, zoonoses, and vectors. The range and numbers of pathogens in municipal wastewater vary with the level of endemic disease in the community, discharges from commercial activities, and seasonal factors. Regulations to control pathogen risk in the United States and Europe arising from land application of biosolids are based on the concept of multiple barriers to the prevention of transmission. The barriers are (i) treatment to reduce pathogen content and vector attraction, (ii) restrictions on crops grown on land to which biosolids have been applied, and (iii) minimum intervals following application and grazing or harvesting. Wastewater treatment reduces number of pathogens in the wastewater by concentrating them with the solids in the sludge. Although some treatment processes are designed specifically to inactivate pathogens, many are not, and the actual mechanisms of microbial inactivation are not fully understood for all processes. Vector attraction is reduced by stabilization (reduction of readily biodegradable material) and/or incorporation immediately following application. Concerns about health risks have renewed interest in the effects of treatment (on pathogens) and advanced treatment methods, and work performed in the United States suggests that Class A pathogen reduction can be achieved less expensively than previously thought. Effective pathogen risk management requires control to the complete chain of sludge treatment, biosolids handling and application, and post-application activities. This may be achieved by adherence to quality management systems based on hazard analysis critical control point (HACCP) principles.

  7. Desempenho de populações híbridas F2 de arroz-vermelho (Oryza sativa com arroz transgênico (O. sativa resistente ao herbicida amonio-glufosinate Performance of F2 hybrid populations of red rice (Oryza sativa with ammonium-glufosinate-resistant transgenic rice (O. sativa

    Directory of Open Access Journals (Sweden)

    J.A. Noldin

    2004-09-01

    -preto. Mesmo assim, os usuários dessa tecnologia deverão adotar, obrigatoriamente, medidas que evitem a possibilidade de cruzamento entre o arroz transgênico e o arroz-vermelho ou arroz-preto.Red rice is an important weed in paddy rice fields. The use of ammonium glufosinate - resistant genetically modified (GM rice cultivars is a viable alternative for controlling red rice in cultivated rice crops. The objective of this study was to evaluate the behavior of F2 hybrid population derivates of crossing between ammonium glufosinate - resistant GM rice and red rice. The F2 hybrid population derivates of crossing between GM rice and red rice are viable but do not present any apparent competitive advantage over red rice. The morphological characteristics of the F2 hybrid populations, such as tillering capacity, number of leaves produced and average plant height were partly reduced and partly unaffected by the introgression of the bar gene. The period between rice planting and 50% flowering increased in the red rice x GM rice F2 hybrids, compared to the parental red rice and GM rice. Average seed shattering rate in the four hybrid families was lower than in the red rice ecotypes, with such aspect also being unfavorable to the persistence of red rice in the environment. Seed dormancy of the hybrids was similar to that of the red rice ecotypes. However, management practices should be adopted to avoid crossing between transgenic rice and red rice.

  8. Extracts against Various Pathogens

    Directory of Open Access Journals (Sweden)

    Ritika Chauhan

    2013-07-01

    The present study shows that tested lichen Parmotrema sp. extracts demonstrated a strong antimicrobial effect. That suggests the active components from methanol extracts of the investigated lichen Parmotrema sp. can be used as natural antimicrobial agent against pathogens.

  9. Evolution of microbial pathogens

    National Research Council Canada - National Science Library

    DiRita, Victor J; Seifert, H. Steven

    2006-01-01

    ... A. Hogan vvi ■ CONTENTS 8. Evolution of Pathogens in Soil Rachel Muir and Man-Wah Tan / 131 9. Experimental Models of Symbiotic Host-Microbial Relationships: Understanding the Underpinnings of ...

  10. Indicators for waterborne pathogens

    National Research Council Canada - National Science Library

    Committee on Indicators for Waterborne Pathogens, National Research Council

    2004-01-01

    ... not practical or feasible to monitor for the complete spectrum of microorganisms that may occur in water, and many known pathogens are difficult to detect directly and reliably in water samples.Â...

  11. Host–Pathogen Interactions

    NARCIS (Netherlands)

    Smits, M.A.; Schokker, D.J.

    2011-01-01

    The outcome of an infection is determined by numerous interactions between hosts and pathogens occurring at many different biological levels, ranging from molecule to population. To develop new control strategies for infectious diseases in livestock species, appropriate methodologies are needed

  12. Determination of glufosinate ammonium and its metabolite, 3-methylphosphinicopropionic acid, in human serum by gas chromatography-mass spectrometry following mixed-mode solid-phase extraction and t-BDMS derivatization.

    Science.gov (United States)

    Hori, Y; Fujisawa, M; Shimada, K; Hirose, Y

    2001-01-01

    A method for the analysis of glufosinate ammonium (GLUF) and its metabolite 3-methylphosphinicopropionic acid (MPPA) in human serum by gas chromatography-mass spectrometry (GC-MS) was developed. Employing a mixed-mode cartridge with both anion exchange action and weak nonpolar interaction, we extracted GLUF and MPPA from the serum and carried out GC-MS analysis of their tert-butyldimethylsilyl derivatives. The detection limits of GLUF and MPPA were 10 pg and 1 pg, respectively. Full mass spectra of 100 pg GLUF and of 10 pg MPPA were easily obtainable. The recovery rate of 90.0+/-11.9% (or better) when the serum concentrations of GLUF and MPPA were 10-0.1 microg/mL. Results of 23 serum samples, from patients with GLUF poisoning, measured by this method correlate well with those derived from the conventional high-performance liquid chromatography method (r = 0.996). The developed GC-MS method is likely to become a useful analytical technique in clinical settings.

  13. Viral pathogen discovery

    Science.gov (United States)

    Chiu, Charles Y

    2015-01-01

    Viral pathogen discovery is of critical importance to clinical microbiology, infectious diseases, and public health. Genomic approaches for pathogen discovery, including consensus polymerase chain reaction (PCR), microarrays, and unbiased next-generation sequencing (NGS), have the capacity to comprehensively identify novel microbes present in clinical samples. Although numerous challenges remain to be addressed, including the bioinformatics analysis and interpretation of large datasets, these technologies have been successful in rapidly identifying emerging outbreak threats, screening vaccines and other biological products for microbial contamination, and discovering novel viruses associated with both acute and chronic illnesses. Downstream studies such as genome assembly, epidemiologic screening, and a culture system or animal model of infection are necessary to establish an association of a candidate pathogen with disease. PMID:23725672

  14. Highly pathogenic avian influenza.

    Science.gov (United States)

    Swayne, D E; Suarez, D L

    2000-08-01

    Highly pathogenic (HP) avian influenza (AI) (HPAI) is an extremely contagious, multi-organ systemic disease of poultry leading to high mortality, and caused by some H5 and H7 subtypes of type A influenza virus, family Orthomyxoviridae. However, most AI virus strains are mildly pathogenic (MP) and produce either subclinical infections or respiratory and/or reproductive diseases in a variety of domestic and wild bird species. Highly pathogenic avian influenza is a List A disease of the Office International des Epizooties, while MPAI is neither a List A nor List B disease. Eighteen outbreaks of HPAI have been documented since the identification of AI virus as the cause of fowl plague in 1955. Mildly pathogenic avian influenza viruses are maintained in wild aquatic bird reservoirs, occasionally crossing over to domestic poultry and causing outbreaks of mild disease. Highly pathogenic avian influenza viruses do not have a recognised wild bird reservoir, but can occasionally be isolated from wild birds during outbreaks in domestic poultry. Highly pathogenic avian influenza viruses have been documented to arise from MPAI viruses through mutations in the haemagglutinin surface protein. Prevention of exposure to the virus and eradication are the accepted methods for dealing with HPAI. Control programmes, which imply allowing a low incidence of infection, are not an acceptable method for managing HPAI, but have been used during some outbreaks of MPAI. The components of a strategy to deal with MPAI or HPAI include surveillance and diagnosis, biosecurity, education, quarantine and depopulation. Vaccination has been used in some control and eradication programmes for AI.

  15. Human pathogen avoidance adaptations

    NARCIS (Netherlands)

    Tybur, J.M.; Lieberman, D.

    2016-01-01

    Over the past few decades, researchers have become increasingly interested in the adaptations guiding the avoidance of disease-causing organisms. Here we discuss the latest developments in this area, including a recently developed information-processing model of the adaptations underlying pathogen

  16. Nitrogen loss in Brachiaria decumbens after application of glyphosate or glufosinate-ammonium Perdas de nitrogênio por Brachiaria decumbens após a aplicação de glifosato ou glufosinato de amônio

    Directory of Open Access Journals (Sweden)

    Virginia Damin

    2008-01-01

    Full Text Available Nitrogen losses from the soil-plant system may be influenced by herbicide applications. In order to evaluate N loss in brachiaria (Brachiaria decumbens after application of the herbicides glyphosate and glufosinate-ammonium, an experiment was carried out in a greenhouse as a completely randomized design, with three treatments and six replicates. Treatments were as follows: i desiccation of brachiaria-plants with glyphosate; ii desiccation of brachiaria-plants with glufosinate-ammonium; and iii control, without herbicide application. The plants were cultivated in 4 kg pots of sandy soil and fertilized with ammonium sulfate- 15N, (200 mg kg-1 in order to quantify the allocation of the fertilizer-N and its recovery in the soil-plant system. Plants treated with the herbicides had less N accumulation and less recovery of the fertilizer-N (15N relative to the control. In the soil, the greatest recovery of 15N-fertilizer occurred for treatments where N was applied, possibly due to the occurrence of other N compound losses to the soil, like root exudation and root death. The total recovery of 15N-fertilizer in the soil-plant system was higher in the control than in the treated plants showing the direct action of the herbicides on nitrogen loss, and especially by the above-ground part of the brachiaria plants.As perdas de nitrogênio no sistema solo-planta podem ser influenciadas pela aplicação de herbicidas. Com o objetivo de avaliar a perda de N do capim-Brachiaria (Brachiaria decumbens após a aplicação dos herbicidas glifosato e glufosinato de amônio, foi realizado um experimento em casa-de-vegetação em delineamento inteiramente aleatorizado (DIA, com três tratamentos e seis repetições. Os tratamentos foram os seguintes: i dessecação de plantas de braquiária com o herbicida glifosato; ii dessecação de plantas de braquiária com herbicida glufosinato de amônio e iii testemunha, sem aplicação de herbicida. As plantas foram cultivadas

  17. Autophagy in plant pathogenic fungi.

    Science.gov (United States)

    Liu, Xiao-Hong; Xu, Fei; Snyder, John Hugh; Shi, Huan-Bin; Lu, Jian-Ping; Lin, Fu-Cheng

    2016-09-01

    Autophagy is a conserved cellular process that degrades cytoplasmic constituents in vacuoles. Plant pathogenic fungi develop special infection structures and/or secrete a range of enzymes to invade their plant hosts. It has been demonstrated that monitoring autophagy processes can be extremely useful in visualizing the sequence of events leading to pathogenicity of plant pathogenic fungi. In this review, we introduce the molecular mechanisms involved in autophagy. In addition, we explore the relationship between autophagy and pathogenicity in plant pathogenic fungi. Finally, we discuss the various experimental strategies available for use in the study of autophagy in plant pathogenic fungi. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Evolution of microbial pathogens.

    OpenAIRE

    Morschhäuser, J; Köhler, G; Ziebuhr, W; Blum-Oehler, G; Dobrindt, U; Hacker, J

    2000-01-01

    Various genetic mechanisms including point mutations, genetic rearrangements and lateral gene transfer processes contribute to the evolution of microbes. Long-term processes leading to the development of new species or subspecies are termed macroevolution, and short-term developments, which occur during days or weeks, are considered as microevolution. Both processes, macro- and microevolution need horizontal gene transfer, which is particularly important for the development of pathogenic micr...

  19. Pathogenic mycoflora on carrot seeds

    Directory of Open Access Journals (Sweden)

    Bogdan Nowicki

    2013-12-01

    Full Text Available Altogether 300 seed samples were collected during 9 years in 8 regions of Poland and the fungi Were isolated and their pathogenicity to carrot seedlings was examined. Alternaria rudicina provcd to be the most important pathogen although. A. alternata was more common. The other important pathogens were Fusarium spp., Phoma spp. and Botrytis cinerea. The infection of carrot seeds by A. radicina should be used as an important criterium in seed quality evaluation.

  20. Pathogenic agents in freshwater resources

    Science.gov (United States)

    Geldreich, Edwin E.

    1996-02-01

    Numerous pathogenic agents have been found in freshwaters used as sources for water supplies, recreational bathing and irrigation. These agents include bacterial pathogens, enteric viruses, several protozoans and parasitic worms more common to tropical waters. Although infected humans are a major source of pathogens, farm animals (cattle, sheep, pigs), animal pets (dogs, cats) and wildlife serve as significant reservoirs and should not be ignored. The range of infected individuals within a given warm-blooded animal group (humans included) may range from 1 to 25%. Survival times for pathogens in the water environment may range from a few days to as much as a year (Ascaris, Taenia eggs), with infective dose levels varying from one viable cell for several primary pathogenic agents to many thousands of cells for a given opportunistic pathogen.As pathogen detection in water is complex and not readily incorporated into routine monitoring, a surrogate is necessary. In general, indicators of faecal contamination provide a positive correlation with intestinal pathogen occurrences only when appropriate sample volumes are examined by sensitive methodology.Pathways by which pathogens reach susceptible water users include ingestion of contaminated water, body contact with polluted recreational waters and consumption of salad crops irrigated by polluted freshwaters. Major contributors to the spread of various water-borne pathogens are sewage, polluted surface waters and stormwater runoff. All of these contributions are intensified during periods of major floods. Several water-borne case histories are cited as examples of breakdowns in public health protection related to water supply, recreational waters and the consumption of contaminated salad crops. In the long term, water resource management must focus on pollution prevention from point sources of waste discharges and the spread of pathogens in watershed stormwater runoff.

  1. Comparative proteomic analysis of pathogenic and non-pathogenic strains from the swine pathogen Mycoplasma hyopneumoniae

    Directory of Open Access Journals (Sweden)

    Klein Cátia S

    2009-12-01

    Full Text Available Abstract Background Mycoplasma hyopneumoniae is a highly infectious swine pathogen and is the causative agent of enzootic pneumonia (EP. Following the previous report of a proteomic survey of the pathogenic 7448 strain of swine pathogen, Mycoplasma hyopneumoniae, we performed comparative protein profiling of three M. hyopneumoniae strains, namely the non-pathogenic J strain and the two pathogenic strains 7448 and 7422. Results In 2DE comparisons, we were able to identify differences in expression levels for 67 proteins, including the overexpression of some cytoadherence-related proteins only in the pathogenic strains. 2DE immunoblot analyses allowed the identification of differential proteolytic cleavage patterns of the P97 adhesin in the three strains. For more comprehensive protein profiling, an LC-MS/MS strategy was used. Overall, 35% of the M. hyopneumoniae genome coding capacity was covered. Partially overlapping profiles of identified proteins were observed in the strains with 81 proteins identified only in one strain and 54 proteins identified in two strains. Abundance analysis of proteins detected in more than one strain demonstrates the relative overexpression of 64 proteins, including the P97 adhesin in the pathogenic strains. Conclusions Our results indicate the physiological differences between the non-pathogenic strain, with its non-infective proliferate lifestyle, and the pathogenic strains, with its constitutive expression of adhesins, which would render the bacterium competent for adhesion and infection prior to host contact.

  2. Transient virulence of emerging pathogens.

    Science.gov (United States)

    Bolker, Benjamin M; Nanda, Arjun; Shah, Dharmini

    2010-05-06

    Should emerging pathogens be unusually virulent? If so, why? Existing theories of virulence evolution based on a tradeoff between high transmission rates and long infectious periods imply that epidemic growth conditions will select for higher virulence, possibly leading to a transient peak in virulence near the beginning of an epidemic. This transient selection could lead to high virulence in emerging pathogens. Using a simple model of the epidemiological and evolutionary dynamics of emerging pathogens, along with rough estimates of parameters for pathogens such as severe acute respiratory syndrome, West Nile virus and myxomatosis, we estimated the potential magnitude and timing of such transient virulence peaks. Pathogens that are moderately evolvable, highly transmissible, and highly virulent at equilibrium could briefly double their virulence during an epidemic; thus, epidemic-phase selection could contribute significantly to the virulence of emerging pathogens. In order to further assess the potential significance of this mechanism, we bring together data from the literature for the shapes of tradeoff curves for several pathogens (myxomatosis, HIV, and a parasite of Daphnia) and the level of genetic variation for virulence for one (myxomatosis). We discuss the need for better data on tradeoff curves and genetic variance in order to evaluate the plausibility of various scenarios of virulence evolution.

  3. Ecological niche of plant pathogens

    Directory of Open Access Journals (Sweden)

    Ecaterina Fodor

    2011-06-01

    Full Text Available Disease ecology is a new approach to the understanding of the spread and dynamics of pathogens in natural and man-made environments. Defining and describing the ecological niche of the pathogens is one of the major tasks for ecological theory, as well as for practitioners preoccupied with the control and forecasting of established and emerging diseases. Niche theory has been periodically revised, not including in an explicit way the pathogens. However, many progresses have been achieved in niche modeling of disease spread, but few attempts were made to construct a theoretical frame for the ecological niche of pathogens. The paper is a review of the knowledge accumulated during last decades in the niche theory of pathogens and proposes an ecological approach in research. It quest for new control methods in what concerns forest plant pathogens, with a special emphasis on fungi like organisms of the genus Phytophthora. Species of Phytophthora are the most successful plant pathogens of the moment, affecting forest and agricultural systems worldwide, many of them being invasive alien organisms in many ecosystems. The hyperspace of their ecological niche is defined by hosts, environment and human interference, as main axes. To select most important variables within the hyperspace, is important the understanding of the complex role of pathogens in the ecosystems as well as for control programs. Biotic relationships within ecosystem of host-pathogen couple are depicted by ecological network and specific metrics attached to this. The star shaped network is characterized by few high degree nodes, by short path lengths and relatively low connectivity, premises for a rapid disturbance spread. 

  4. Ecological niche of plant pathogens

    Directory of Open Access Journals (Sweden)

    Ecaterina Fodor

    2011-02-01

    Full Text Available Disease ecology is a new approach to the understanding of the spread and dynamics of pathogens in natural and man-made environments. Defining and describing the ecological niche of the pathogens is one of the major tasks for ecological theory, as well as for practitioners preoccupied with the control and forecasting of established and emerging diseases. Niche theory has been periodically revised, not including in an explicit way the pathogens. However, many progresses have been achieved in niche modeling of disease spread, but few attempts were made to construct a theoretical frame for the ecological niche of pathogens. The paper is a review of the knowledge accumulated during last decades in the niche theory of pathogens and proposes an ecological approach in research. It quest for new control methods in what concerns forest plant pathogens, with a special emphasis on fungi like organisms of the genus Phytophthora. Species of Phytophthora are the most successful plant pathogens of the moment, affecting forest and agricultural systems worldwide, many of them being invasive alien organisms in many ecosystems. The hyperspace of their ecological niche is defined by hosts, environment and human interference, as main axes. To select most important variables within the hyperspace, is important for the understanding of the complex role of pathogens in the ecosystems as well as for control programs. Biotic relationships within ecosystem of host-pathogen couple are depicted by ecological network and specific metrics attached to this. The star shaped network is characterized by few high degree nodes, by short path lengths and relatively low connectivity, premises for a rapid disturbance spread.

  5. Host pathogen relations: exploring animal models for fungal pathogens.

    Science.gov (United States)

    Harwood, Catherine G; Rao, Reeta P

    2014-06-30

    Pathogenic fungi cause superficial infections but pose a significant public health risk when infections spread to deeper tissues, such as the lung. Within the last three decades, fungi have been identified as the leading cause of nosocomial infections making them the focus of research. This review outlines the model systems such as the mouse, zebrafish larvae, flies, and nematodes, as well as ex vivo and in vitro systems available to study common fungal pathogens.

  6. Host Pathogen Relations: Exploring Animal Models for Fungal Pathogens

    Directory of Open Access Journals (Sweden)

    Catherine G. Harwood

    2014-06-01

    Full Text Available Pathogenic fungi cause superficial infections but pose a significant public health risk when infections spread to deeper tissues, such as the lung. Within the last three decades, fungi have been identified as the leading cause of nosocomial infections making them the focus of research. This review outlines the model systems such as the mouse, zebrafish larvae, flies, and nematodes, as well as ex vivo and in vitro systems available to study common fungal pathogens.

  7. Tropism and pathogenicity of rickettsiae

    Directory of Open Access Journals (Sweden)

    Tsuneo eUchiyama

    2012-06-01

    Full Text Available Rickettsiae are obligate intracellular parasitic bacteria that cause febrile exanthematous illnesses such as Rocky Mountain spotted fever, Mediterranean spotted fever, epidemic and murine typhus, etc. Although the vector ranges of each Rickettsia species are rather restricted; i.e., ticks belonging to Arachnida and lice and fleas belonging to Insecta usually act as vectors for spotted fever group and typhus group rickettsiae, respectively, it would be interesting to elucidate the mechanisms controlling the vector tropism of rickettsiae. This review discusses the factors determining the vector tropism of rickettsiae. In brief, the vector tropism of rickettsiae species is basically consistent with their tropism towards cultured tick and insect cells. The mechanisms responsible for rickettsiae pathogenicity are also described. Recently, genomic analyses of rickettsiae have revealed that they possess several genes that are homologous to those affecting the pathogenicity of other bacteria. Analyses comparing the genomes of pathogenic and nonpathogenic strains of rickettsiae have detected many factors that are related to rickettsial pathogenicity. It is also known that a reduction in the rickettsial genome has occurred during the course of its evolution. Interestingly, Rickettsia species with small genomes, such as Rickettsia prowazekii, are more pathogenic to humans than those with larger genomes. This review also examines the growth kinetics of pathogenic and nonpathogenic species of spotted fever group rickettsiae in mammalian cells. The growth of nonpathogenic species is restricted in these cells, which is mediated, at least in part, by autophagy. The superinfection of nonpathogenic rickettsiae-infected cells with pathogenic rickettsiae results in an elevated yield of the nonpathogenic rickettsiae and the growth of the pathogenic rickettsiae. Autophagy is restricted in these cells. These results are discussed in this review.

  8. Pathogen avoidance by insect predators

    OpenAIRE

    Meyling, Nicolai V.; Ormond, Emma; Roy, Helen E.; Pell, Judith K.

    2008-01-01

    Insects can detect cues related to the risk of attack by their natural enemies. Pathogens are among the natural enemies of insects and entomopathogenic fungi attack a wide array of host species. Evidence documents that social insects in particular have adapted behavioural mechanisms to avoid infection by fungal pathogens. These mechanisms are referred to as 'behavioural resistance'. However, there is little evidence for similar adaptations in non-social insects. We have conducted experime...

  9. Antibiotic Resistance in Foodborne Pathogens

    OpenAIRE

    Walsh, Ciara; Duffy, Geraldine

    2013-01-01

    Wide-spread antibiotic resistance among bacterial pathogens is now a serious public health issue and multi-antibiotic resistance has been reported in many foodborne pathogens including Salmonella and E. coli. A study to determine antibiotic resistance profiles of a range of Salmonella and Verocytotoxigenic E.coli (VTEC) isolated from Irish foods revealed significant levels of antibiotic resistance in the strains. S. typhimurium DT104 were multiantibiotic resistant with 97% resistant to 7 anti...

  10. Molecular detection of human bacterial pathogens

    National Research Council Canada - National Science Library

    Liu, Dongyou

    2011-01-01

    .... Molecular Detection of Human Bacterial Pathogens addresses this issue, with international scientists in respective bacterial pathogen research and diagnosis providing expert summaries on current...

  11. Biosensors for plant pathogen detection.

    Science.gov (United States)

    Khater, Mohga; de la Escosura-Muñiz, Alfredo; Merkoçi, Arben

    2017-07-15

    Infectious plant diseases are caused by pathogenic microorganisms such as fungi, bacteria, viruses, viroids, phytoplasma and nematodes. Worldwide, plant pathogen infections are among main factors limiting crop productivity and increasing economic losses. Plant pathogen detection is important as first step to manage a plant disease in greenhouses, field conditions and at the country boarders. Current immunological techniques used to detect pathogens in plant include enzyme-linked immunosorbent assays (ELISA) and direct tissue blot immunoassays (DTBIA). DNA-based techniques such as polymerase chain reaction (PCR), real time PCR (RT-PCR) and dot blot hybridization have also been proposed for pathogen identification and detection. However these methodologies are time-consuming and require complex instruments, being not suitable for in-situ analysis. Consequently, there is strong interest for developing new biosensing systems for early detection of plant diseases with high sensitivity and specificity at the point-of-care. In this context, we revise here the recent advancement in the development of advantageous biosensing systems for plant pathogen detection based on both antibody and DNA receptors. The use of different nanomaterials such as nanochannels and metallic nanoparticles for the development of innovative and sensitive biosensing systems for the detection of pathogens (i.e. bacteria and viruses) at the point-of-care is also shown. Plastic and paper-based platforms have been used for this purpose, offering cheap and easy-to-use really integrated sensing systems for rapid on-site detection. Beside devices developed at research and development level a brief revision of commercially available kits is also included in this review. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. 77 FR 59106 - Glufosinate Ammonium; Pesticide Tolerances

    Science.gov (United States)

    2012-09-26

    ... response to the notices of filing. Based upon review of the data supporting the petition, EPA is: (1... 408(b)(2)(D), EPA has reviewed the available scientific data and other relevant information in support... sensitizer. Subchronic toxicity studies in rats showed inhibition of glutamate synthetase and lead the Agency...

  13. Pathogenicity of highly pathogenic avian influenza virus in mammals

    NARCIS (Netherlands)

    de Wit, Emmie; Kawaoka, Yoshihiro; de Jong, Menno D.; Fouchier, Ron A. M.

    2008-01-01

    In recent years, there has been an increase in outbreaks of highly pathogenic avian influenza (HPAI) in poultry. Occasionally, these outbreaks have resulted in transmission of influenza viruses to humans and other mammals, with symptoms ranging from conjunctivitis to pneumonia and death. Here, the

  14. New trends in emerging pathogens.

    Science.gov (United States)

    Skovgaard, Niels

    2007-12-15

    The emergence of pathogens is the result of a number of impact in all parts of the food chain. The emerging technologies in food production explain how new pathogens can establish themselves in the food chain and compromise food safety. The impact of the food technology is analysed for several bacteria, such as Yersinia, Campylobacter, Arcobacter, Helicobacter pullorum, Enterobacter sakazakii, Mycobacterium avium spp. paratuberculosis, prions related to vCJD and others. The importance of the ability of many microbes to form VBNC forms is elaborated on. Research on culture independent methods may address this outstanding issue to the better understanding of emerging pathogens. The "demerging" of pathogens also occur, and examples of this are explained. The reaction of bacteria to stresses and sublethal treatments, and how exposure to one stress factor can confer resistance to other stresses, literally speaking causing contagious resistance, are explained. The implication of this e.g. in modern approaches of food preservation, such as Minimally processed Foods, is considerable. Intestinal colonization of EHEC may be regulated by Quorum sensing, and this ability of microbes plays an important role in the colonization of microbes in food and on food processing equipment, an important factor in the emergence of pathogens. The emergence of Saccharomyces cerevisiae, as an opportunistic human pathogen, used for centuries for food and production of alcoholic beverages, calls for research in molecular tools to distinguish between probiotic and clinical strains. Cyclospora cayetanensis and Norovirus outbreaks can no longer be designated as emerging pathogens, they share however one characteristic in the epidemiology of emerging nature, the importance of the hygiene in the primary production stage, including supply of potable water, and the application of GMP and the HACCP principles in the beginning of the food chain. Hepatitis E virus is a potential emerging food borne

  15. Applied Genomics of Foodborne Pathogens

    DEFF Research Database (Denmark)

    and customized source of information designed for and accessible to microbiologists interested in applying cutting-edge genomics in food safety and public health research. This book fills this void with a well-selected collection of topics, case studies, and bioinformatics tools contributed by experts......This book provides a timely and thorough snapshot into the emerging and fast evolving area of applied genomics of foodborne pathogens. Driven by the drastic advance of whole genome shot gun sequencing (WGS) technologies, genomics applications are becoming increasingly valuable and even essential...... at the forefront of foodborne pathogen genomics research....

  16. Pathogen disgust and interpersonal personality

    NARCIS (Netherlands)

    Kupfer, Tom R.; Tybur, Joshua M.

    2017-01-01

    The behavioral immune system includes motivational systems for avoiding contact with pathogens, including those transmitted by other people. Motivations to avoid others may depend not only on the perceived risk of infection but also on perceived benefits of social interaction. Based on this idea, we

  17. Lectins in human pathogenic fungi.

    Science.gov (United States)

    Gallegos, Belém; Martínez, Ruth; Pérez, Laura; Del Socorro Pina, María; Perez, Eduardo; Hernández, Pedro

    2014-01-01

    Lectins are carbohydrate-binding proteins widely distributed in nature. They constitute a highly diverse group of proteins consisting of many different protein families that are, in general, structurally unrelated. In the last few years, mushroom and other fungal lectins have attracted wide attention due to their antitumour, antiproliferative and immunomodulatory activities. The present mini-review provides concise information about recent developments in understanding lectins from human pathogenic fungi. A bibliographic search was performed in the Science Direct and PubMed databases, using the following keywords "lectin", "fungi", "human" and "pathogenic". Lectins present in fungi have been classified; however, the role played by lectins derived from human pathogenic fungi in infectious processes remains uncertain; thus, this is a scientific field requiring more research. This manuscript is part of the series of works presented at the "V International Workshop: Molecular genetic approaches to the study of human pathogenic fungi" (Oaxaca, Mexico, 2012). Copyright © 2013 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  18. Pathogenicity of Shigella in chickens.

    Science.gov (United States)

    Shi, Run; Yang, Xia; Chen, Lu; Chang, Hong-tao; Liu, Hong-ying; Zhao, Jun; Wang, Xin-wei; Wang, Chuan-qing

    2014-01-01

    Shigellosis in chickens was first reported in 2004. This study aimed to determine the pathogenicity of Shigella in chickens and the possibility of cross-infection between humans and chickens. The pathogenicity of Shigella in chickens was examined via infection of three-day-old SPF chickens with Shigella strain ZD02 isolated from a human patient. The virulence and invasiveness were examined by infection of the chicken intestines and primary chicken intestinal epithelial cells. The results showed Shigella can cause death via intraperitoneal injection in SPF chickens, but only induce depression via crop injection. Immunohistochemistry and transmission electron microscopy revealed the Shigella can invade the intestinal epithelia. Immunohistochemistry of the primary chicken intestinal epithelial cells infected with Shigella showed the bacteria were internalized into the epithelial cells. Electron microscopy also confirmed that Shigella invaded primary chicken intestinal epithelia and was encapsulated by phagosome-like membranes. Our data demonstrate that Shigella can invade primary chicken intestinal epithelial cells in vitro and chicken intestinal mucosa in vivo, resulting in pathogenicity and even death. The findings suggest Shigella isolated from human or chicken share similar pathogenicity as well as the possibility of human-poultry cross-infection, which is of public health significance.

  19. Pathogen reduction of blood components.

    Science.gov (United States)

    Solheim, Bjarte G

    2008-08-01

    Thanks to many blood safety interventions introduced in developed countries the risk of transfusion transmitted infections has become exceedingly small in these countries. However, emerging pathogens still represent a serious challenge, as demonstrated by West Nile virus in the US and more recently by Chikungunya virus in the Indian Ocean. In addition bacterial contamination, particularly in platelets, and protozoa transmitted by blood components still represent sizeable risks in developed countries. In developing countries the risk of all transfusion transmitted infections is still high due to insufficient funding and organisation of the health service. Pathogen reduction of pooled plasma products has virtually eliminated the risk of transfusion transmitted infections, without compromising the quality of the products significantly. Pathogen reduction of blood components has been much more challenging. Solvent detergent treatment which has been so successfully applied for plasma products dissolves cell membranes, and can, therefore, only be applied for plasma and not for cellular blood components. Targeting of nucleic acids has been another method for pathogen inactivation of plasma and the only approach possible for cellular blood products. As documented in more than 15 year's track record, solvent detergent treatment of pooled plasma can yield high quality plasma. The increased risk for contamination by unknown viruses due to pooling is out weighed by elimination of TRALI, significant reduction in allergic reactions and standardisation of the product. Recently, a promising method for solvent detergent treatment of single donor plasma units has been published. Methylene blue light treatment of single donor plasma units has a similar long track record as pooled solvent detergent treated plasma; but the method is less well documented and affects coagulation factor activity more. Psoralen light treated plasma has only recently been introduced (CE marked in Europe

  20. Neuroepigenetic Regulation of Pathogenic Memories.

    Science.gov (United States)

    Sillivan, Stephanie E; Vaissière, Thomas; Miller, Courtney A

    2015-01-01

    Our unique collection of memories determines our individuality and shapes our future interactions with the world. Remarkable advances into the neurobiological basis of memory have identified key epigenetic mechanisms that support the stability of memory. Various forms of epigenetic regulation at the levels of DNA methylation, histone modification, and non-coding RNAs (ncRNAs) can modulate transcriptional and translational events required for memory processes. By changing the cellular profile in the brain's emotional, reward, and memory circuits, these epigenetic modifications have also been linked to perseverant, pathogenic memories. In this review, we will delve into the relevance of epigenetic dysregulation to pathogenic memory mechanisms by focusing on two neuropsychiatric disorders perpetuated by aberrant memory associations: substance use disorder (SUD) and post-traumatic stress disorder (PTSD). As our understanding improves, neuroepigenetic mechanisms may someday be harnessed to develop novel therapeutic targets for the treatment of these chronic, relapsing disorders.

  1. Neuroepigenetic regulation of pathogenic memories

    Directory of Open Access Journals (Sweden)

    Stephanie E. Sillivan

    2015-01-01

    Full Text Available Our unique collection of memories determines our individuality and shapes our future interactions with the world. Remarkable advances into the neurobiological basis of memory have identified key epigenetic mechanisms that support the stability of memory. Various forms of epigenetic regulation at the levels of DNA methylation, histone modification, and noncoding RNAs can modulate transcriptional and translational events required for memory processes. By changing the cellular profile in the brain’s emotional, reward, and memory circuits, these epigenetic modifications have also been linked to perseverant, pathogenic memories. In this review, we will delve into the relevance of epigenetic dysregulation to pathogenic memory mechanisms by focusing on 2 neuropsychiatric disorders perpetuated by aberrant memory associations: substance use disorder and post-traumatic stress disorder. As our understanding improves, neuroepigenetic mechanisms may someday be harnessed to develop novel therapeutic targets for the treatment of these chronic, relapsing disorders.

  2. Antimicrobial resistance of mastitis pathogens.

    Science.gov (United States)

    Oliver, Stephen P; Murinda, Shelton E

    2012-07-01

    Antibiotics are used extensively in the dairy industry to combat disease and to improve animal performance. Antibiotics such as penicillin, cephalosporin, streptomycin, and tetracycline are used for the treatment and prevention of diseases affecting dairy cows caused by a variety of gram-positive and gram-negative bacteria. Antibiotics are often administrated routinely to entire herds to prevent mastitis during the dry period. An increase in the incidence of disease in a herd generally results in increased use of antimicrobials, which in turn increases the potential for antibiotic residues in milk and the potential for increased bacterial resistance to antimicrobials. Continued use of antibiotics in the treatment and prevention of diseases of dairy cows will continue to be scrutinized. It is clear that strategies employing the prudent use of antimicrobials are needed. This clearly illustrates the importance of effective herd disease prevention and control programs. Based on studies published to date, scientific evidence does not support widespread, emerging resistance among mastitis pathogens to antibacterial drugs even though many of these antibiotics have been used in the dairy industry for treatment and prevention of disease for several decades. However, it is clear that use of antibiotics in dairy cows can contribute to increased antimicrobial resistance. While antimicrobial resistance does occur, we are of the opinion that the advantages of using antibiotics for the treatment of mastitis far outweigh the disadvantages. The clinical consequences of antimicrobial resistance of dairy pathogens affecting humans appear small. Antimicrobial resistance among dairy pathogens, particularly those found in milk, is likely not a human health concern as long as the milk is pasteurized. However, there are an increasing number of people who choose to consume raw milk. Transmission of an antimicrobial-resistant mastitis pathogen and/or foodborne pathogen to humans could occur

  3. Evolutionary biology of bacterial and fungal pathogens

    National Research Council Canada - National Science Library

    Baquero, F

    2008-01-01

    ... and Evolutionary Dynamics of Pathogens * 21 Keith A. Crandall and Marcos Pérez-Losada II. Evolutionary Genetics of Microbial Pathogens 4. Environmental and Social Influences on Infectious Disea...

  4. Plant Pathogenicity in Spaceflight Environments

    OpenAIRE

    Bishop, Deborah L.; Levine, Howard G.; Anderson, Anne J.

    1996-01-01

    Plants grown in microgravity are subject to many environmental stresses, which may promote microbial growth and result in pathogenicity to the plant. Recent plant experiments with super dwarf wheat aboard the NASA Space Shuttle and NASA/Russian Mir Space Station returned from the mission with severe degrees of fungal contamination. Understanding the cause of such microbial contamination and methods to eliminate it are necessary prerequisites for continued plant growth and development studies ...

  5. Proteomics of Plant Pathogenic Fungi

    Directory of Open Access Journals (Sweden)

    Raquel González-Fernández

    2010-01-01

    Full Text Available Plant pathogenic fungi cause important yield losses in crops. In order to develop efficient and environmental friendly crop protection strategies, molecular studies of the fungal biological cycle, virulence factors, and interaction with its host are necessary. For that reason, several approaches have been performed using both classical genetic, cell biology, and biochemistry and the modern, holistic, and high-throughput, omic techniques. This work briefly overviews the tools available for studying Plant Pathogenic Fungi and is amply focused on MS-based Proteomics analysis, based on original papers published up to December 2009. At a methodological level, different steps in a proteomic workflow experiment are discussed. Separate sections are devoted to fungal descriptive (intracellular, subcellular, extracellular and differential expression proteomics and interactomics. From the work published we can conclude that Proteomics, in combination with other techniques, constitutes a powerful tool for providing important information about pathogenicity and virulence factors, thus opening up new possibilities for crop disease diagnosis and crop protection.

  6. Minisequencing mitochondrial DNA pathogenic mutations

    Directory of Open Access Journals (Sweden)

    Carracedo Ángel

    2008-04-01

    Full Text Available Abstract Background There are a number of well-known mutations responsible of common mitochondrial DNA (mtDNA diseases. In order to overcome technical problems related to the analysis of complete mtDNA genomes, a variety of different techniques have been proposed that allow the screening of coding region pathogenic mutations. Methods We here propose a minisequencing assay for the analysis of mtDNA mutations. In a single reaction, we interrogate a total of 25 pathogenic mutations distributed all around the whole mtDNA genome in a sample of patients suspected for mtDNA disease. Results We have detected 11 causal homoplasmic mutations in patients suspected for Leber disease, which were further confirmed by standard automatic sequencing. Mutations m.11778G>A and m.14484T>C occur at higher frequency than expected by change in the Galician (northwest Spain patients carrying haplogroup J lineages (Fisher's Exact test, P-value Conclusion We here developed a minisequencing genotyping method for the screening of the most common pathogenic mtDNA mutations which is simple, fast, and low-cost. The technique is robust and reproducible and can easily be implemented in standard clinical laboratories.

  7. Molecular Mechanisms of Bacterial Pathogenicity

    Science.gov (United States)

    Fuchs, Thilo Martin

    Cautious optimism has arisen over recent decades with respect to the long struggle against bacteria, viruses, and parasites. This has been offset, however, by a fatal complacency stemming from previous successes such as the development of antimicrobial drugs, the eradication of smallpox, and global immunization programs. Infectious diseases nevertheless remain the world's leading cause of death, killing at least 17 million persons annually [61]. Diarrheal diseases caused by Vibrio cholerae or Shigella dysenteriae kill about 3 million persons every year, most of them young children: Another 4 million die of tuberculosis or tetanus. Outbreaks of diphtheria in Eastern Europe threatens the population with a disease that had previously seemed to be overcome. Efforts to control infectious diseases more comprehensively are undermined not only by socioeconomic conditions but also by the nature of the pathogenic organisms itself; some isolates of Staphylococcus aureus and Enterobacter have become so resistant to drugs by horizontal gene transfer that they are almost untreatable. In addition, the mechanism of genetic variability helps pathogens to evade the human immune system, thus compromising the development of powerful vaccines. Therefore detailed knowledge of the molecular mechanisms of microbial pathogenicity is absolutely necessary to develop new strategies against infectious diseases and thus to lower their impact on human health and social development.

  8. Plant innate immunity against human bacterial pathogens

    Directory of Open Access Journals (Sweden)

    Maeli eMelotto

    2014-08-01

    Full Text Available Certain human bacterial pathogens such as the enterohemorrhagic Escherichia coli and Salmonella enterica are not proven to be plant pathogens yet. Nonetheless, under certain conditions they can survive on, penetrate into, and colonize internal plant tissues causing serious food borne disease outbreaks. In this review, we highlight current understanding on the molecular mechanisms of plant responses against human bacterial pathogens and discuss salient common and contrasting themes of plant interactions with phytopathogens or human pathogens.

  9. Effectiveness of irradiation in killing pathogens

    International Nuclear Information System (INIS)

    Yeager, J.G.; Ward, R.L.

    1980-01-01

    United States Environmental Protection Agency regulations include gamma ray irradiation of sludge as an approved Process to Further Reduce Pathogens (PFRP) prior to land application. Research at Sandia National Laboratories on pathogen inactivation in sludge by gamma irradiation has demonstrated that the 1 Mrad PFRP dose is capable, by itself, of eliminating bacterial, fungal, and parasitic pathogens from sludge. Gamma irradiation of sludge in conjunction with the required Processes to Significantly Reduce Pathogens (PSRP) should also eliminate the viral hazard from wastewater sludges

  10. 76 FR 24793 - Highly Pathogenic Avian Influenza

    Science.gov (United States)

    2011-05-03

    .... APHIS-2006-0074] RIN 0579-AC36 Highly Pathogenic Avian Influenza AGENCY: Animal and Plant Health... any subtype of highly pathogenic avian influenza is considered to exist. The interim rule also imposed... avian influenza, or that have moved through regions where any subtype of highly pathogenic avian...

  11. Epigenetic control of effectors in plant pathogens

    Directory of Open Access Journals (Sweden)

    Mark eGijzen

    2014-11-01

    Full Text Available Plant pathogens display impressive versatility in adapting to host immune systems. Pathogen effector proteins facilitate disease but can become avirulence (Avr factors when the host acquires discrete recognition capabilities that trigger immunity. The mechanisms that lead to changes to pathogen Avr factors that enable escape from host immunity are diverse, and include epigenetic switches that allow for reuse or recycling of effectors. This perspective outlines possibilities of how epigenetic control of Avr effector gene expression may have arisen and persisted in plant pathogens, and how it presents special problems for diagnosis and detection of specific pathogen strains or pathotypes.

  12. Future research needs involving pathogens in groundwater

    Science.gov (United States)

    Bradford, Scott A.; Harvey, Ronald W.

    2017-01-01

    Contamination of groundwater by enteric pathogens has commonly been associated with disease outbreaks. Proper management and treatment of pathogen sources are important prerequisites for preventing groundwater contamination. However, non-point sources of pathogen contamination are frequently difficult to identify, and existing approaches for pathogen detection are costly and only provide semi-quantitative information. Microbial indicators that are readily quantified often do not correlate with the presence of pathogens. Pathogens of emerging concern and increasing detections of antibiotic resistance among bacterial pathogens in groundwater are topics of growing concern. Adequate removal of pathogens during soil passage is therefore critical for safe groundwater extraction. Processes that enhance pathogen transport (e.g., high velocity zones and preferential flow) and diminish pathogen removal (e.g., reversible retention and enhanced survival) are of special concern because they increase the risk of groundwater contamination, but are still incompletely understood. Improved theory and modeling tools are needed to analyze experimental data, test hypotheses, understand coupled processes and controlling mechanisms, predict spatial and/or temporal variability in model parameters and uncertainty in pathogen concentrations, assess risk, and develop mitigation and best management approaches to protect groundwater.

  13. Future research needs involving pathogens in groundwater

    Science.gov (United States)

    Bradford, Scott A.; Harvey, Ronald W.

    2017-06-01

    Contamination of groundwater by enteric pathogens has commonly been associated with disease outbreaks. Proper management and treatment of pathogen sources are important prerequisites for preventing groundwater contamination. However, non-point sources of pathogen contamination are frequently difficult to identify, and existing approaches for pathogen detection are costly and only provide semi-quantitative information. Microbial indicators that are readily quantified often do not correlate with the presence of pathogens. Pathogens of emerging concern and increasing detections of antibiotic resistance among bacterial pathogens in groundwater are topics of growing concern. Adequate removal of pathogens during soil passage is therefore critical for safe groundwater extraction. Processes that enhance pathogen transport (e.g., high velocity zones and preferential flow) and diminish pathogen removal (e.g., reversible retention and enhanced survival) are of special concern because they increase the risk of groundwater contamination, but are still incompletely understood. Improved theory and modeling tools are needed to analyze experimental data, test hypotheses, understand coupled processes and controlling mechanisms, predict spatial and/or temporal variability in model parameters and uncertainty in pathogen concentrations, assess risk, and develop mitigation and best management approaches to protect groundwater.

  14. Pathogen recognition in the innate immune response.

    Science.gov (United States)

    Kumar, Himanshu; Kawai, Taro; Akira, Shizuo

    2009-04-28

    Immunity against microbial pathogens primarily depends on the recognition of pathogen components by innate receptors expressed on immune and non-immune cells. Innate receptors are evolutionarily conserved germ-line-encoded proteins and include TLRs (Toll-like receptors), RLRs [RIG-I (retinoic acid-inducible gene-I)-like receptors] and NLRs (Nod-like receptors). These receptors recognize pathogens or pathogen-derived products in different cellular compartments, such as the plasma membrane, the endosomes or the cytoplasm, and induce the expression of cytokines, chemokines and co-stimulatory molecules to eliminate pathogens and instruct pathogen-specific adaptive immune responses. In the present review, we will discuss the recent progress in the study of pathogen recognition by TLRs, RLRs and NLRs and their signalling pathways.

  15. Contamination of water resources by pathogenic bacteria

    Science.gov (United States)

    2014-01-01

    Water-borne pathogen contamination in water resources and related diseases are a major water quality concern throughout the world. Increasing interest in controlling water-borne pathogens in water resources evidenced by a large number of recent publications clearly attests to the need for studies that synthesize knowledge from multiple fields covering comparative aspects of pathogen contamination, and unify them in a single place in order to present and address the problem as a whole. Providing a broader perceptive of pathogen contamination in freshwater (rivers, lakes, reservoirs, groundwater) and saline water (estuaries and coastal waters) resources, this review paper attempts to develop the first comprehensive single source of existing information on pathogen contamination in multiple types of water resources. In addition, a comprehensive discussion describes the challenges associated with using indicator organisms. Potential impacts of water resources development on pathogen contamination as well as challenges that lie ahead for addressing pathogen contamination are also discussed. PMID:25006540

  16. Complement Evasion by Pathogenic Leptospira.

    Science.gov (United States)

    Fraga, Tatiana Rodrigues; Isaac, Lourdes; Barbosa, Angela Silva

    2016-01-01

    Leptospirosis is a neglected infectious disease caused by spirochetes from the genus Leptospira . Pathogenic microorganisms, notably those which reach the blood circulation such as Leptospira , have evolved multiple strategies to escape the host complement system, which is important for innate and acquired immunity. Leptospira avoid complement-mediated killing through: (i) recruitment of host complement regulators; (ii) acquisition of host proteases that cleave complement proteins on the bacterial surface; and, (iii) secretion of proteases that inactivate complement proteins in the Leptospira surroundings. The recruitment of host soluble complement regulatory proteins includes the acquisition of Factor H (FH) and FH-like-1 (alternative pathway), C4b-binding protein (C4BP) (classical and lectin pathways), and vitronectin (Vn) (terminal pathway). Once bound to the leptospiral surface, FH and C4BP retain cofactor activity of Factor I in the cleavage of C3b and C4b, respectively. Vn acquisition by leptospires may result in terminal pathway inhibition by blocking C9 polymerization. The second evasion mechanism lies in plasminogen (PLG) binding to the leptospiral surface. In the presence of host activators, PLG is converted to enzymatically active plasmin, which is able to degrade C3b, C4b, and C5 at the surface of the pathogen. A third strategy used by leptospires to escape from complement system is the active secretion of proteases. Pathogenic, but not saprophytic leptospires, are able to secrete metalloproteases that cleave C3 (central complement molecule), Factor B (alternative pathway), and C4 and C2 (classical and lectin pathways). The purpose of this review is to fully explore these complement evasion mechanisms, which act together to favor Leptospira survival and multiplication in the host.

  17. Icu Pathogens: A Continuous Challenge

    International Nuclear Information System (INIS)

    Hafeez, A.; Munir, T.; Najeeb, S.; Rehman, S.; Gilani, M.

    2016-01-01

    Objective: To determine the frequency and antibiogram of pathogens in an intensive care unit (ICU). Study Design: Cross-sectional, observational study. Place and Duration of Study: Department of Microbiology, Army Medical College, National University of Science and Technology, Islamabad, from January 2013 to January 2014. Methodology: Clinical samples, received from patients admitted in ICU, were inoculated on various medias like blood agar, chocolate agar, MacConkey agar and urine samples on CLED. These were then incubated at 37 degree C for 24 hours. Isolates were identified by colony morphology, Gram reaction, catalase test, oxidase test. Species identification in case of Gram Negative Rods was done by using API 20E (BioMerieux). Antibiotic susceptibility was done by using modified KirbyBauer disc diffusion technique. Bacterial isolates were prepared and inoculated on Mueller-Hinton agar plates followed by application of various antibiotic disc (Oxoid, UK) as per manufacturer's instructions. The plates were then incubated at 37 degree C aerobically for 18 - 24 hours. Zone diameters were measured and interpreted as sensitive and resistant, according to Clinical and Laboratory Standards Institute (CLSI) guidelines. Results: Out of the 367 positive cultures, 116 (31.08 percent) were Acinetobacter baumanniisusceptible to minocycline and tigecycline followed by Klebsiella pneumoniae (n=71, 16 percent) susceptible to tigecycline and meropenem. Others were Pseudomonas aeruginosa, Escherichia coli Coagulase Negative Staphylococcus, Staphylococcus aureus, Enterococcus spp., Streptococcus spp., Klebsiella oxytoca, Stenotrophomonas maltophilia, and Candida spp. Conclusion: Acinetobacter baumannii was the most frequently isolated pathogen. Most of the cultures yielding pathogens were from respiratory tract samples. Gram negative isolates were multidrug resistant but most were tigecycline and susceptible to meropenem. (author)

  18. COXIELLA BURNETII PATHOGENICITY MOLECULAR BASIS

    Directory of Open Access Journals (Sweden)

    Yu. A. Panferova

    2016-01-01

    Full Text Available Coxiella burnetii is an obligate intracellular gram-negative bacterial pathogen, an ethiological agent of Q-fever, a zoonotic disease, elapsing as an acute (mostly atypical pneumonia or a chronic (mostly endocarditis form. The host range is represented by wide range of mammal, avian and arthropod species, but the main source of human infection are farm animals. The main route of infection is aerosolic. In case of contact with organism pathogen binds with phagocytal monocytic-macrophagal cell line. C. burnetii promotes maturation of specific phagolysosome-like compartment in host cell, called coxiella-containing vacuole, within this vacuole pathogen becames metabolically activated and actively replicates. Coxiella persists as metabolically inactive spore-like form in environment. Internalisation of C. burnetii occurs using actin-mediated phagocytosis and zipper mechanism. After internalization of bacteria maturation of phagolysosome-like compartment and large coxiella-containing vacuole formation occure, and vacuole can occupy nearly the whole cytoplasm of the host cell. Survivance of infected cells is important for chronic infection with C. burnetii. C. burnetii elongate the viability of host cell by two ways: it actively inhibits apoptotic signal cascades and induce pro-survival factors. Exceptthat C. burnetii involves autophagic pathway during coxiella-containing vacuole formation, and induction of autophagy promotes pathogen replication. During infection C. burnetii translocates effector substrates from bacterial cytosole to euca ryotic host cell cytosole using type IV secretion system, where effectors modulate host cell proteins. Overall approximately 130 secreted effectors of type IV transport system, but function of most of them remains unknown to date. Specific sec reted proteins for variety of strains and isolates were identified, confirmed that certain pathotypes of C. burnetii can exist. Identification and

  19. Streptococcus agalactiae: a vaginal pathogen?

    Science.gov (United States)

    Maniatis, A N; Palermos, J; Kantzanou, M; Maniatis, N A; Christodoulou, C; Legakis, N J

    1996-03-01

    The significance of Streptococcus agalactiae as an aetiological agent in vaginitis was evaluated. A total of 6226 samples from women who presented with vaginal symptoms was examined. The presence of >10 leucocytes/high-power field (h.p.f.) was taken to be the criterion of active infection. S. agalactiae was isolated from 10.1% of these samples. The isolation rates of other common pathogens such as Candida spp., Gardnerella vaginalis and Trichomonas spp. were 54.1%, 27.2% and 4.2%, respectively, in the same group of patients. In contrast, the isolation rates of these micro-organisms in the group of patients who had no infection (S. agalactiae was isolated, it was the sole pathogen isolated (83%) and its presence was associated with an inflammatory response in 80% of patients. Furthermore, the relative risk of vaginal infection with S. agalactiae (2.38) in patients with purulent vaginal discharge was greater than that of Candida spp. infection (1.41) and lower than that of Trichomonas spp. infection (8.32). These data suggest that S. agalactiae in symptomatic women with microscopic evidence of inflammation should be considered a causative agent of vaginitis.

  20. Interaction of pathogens with host cholesterol metabolism.

    Science.gov (United States)

    Sviridov, Dmitri; Bukrinsky, Michael

    2014-10-01

    Pathogens of different taxa, from prions to protozoa, target cellular cholesterol metabolism to advance their own development and to impair host immune responses, but also causing metabolic complications, for example, atherosclerosis. This review describes recent findings of how pathogens do it. A common theme in interaction between pathogens and host cholesterol metabolism is pathogens targeting lipid rafts of the host plasma membrane. Many intracellular pathogens use rafts as an entry gate, taking advantage of the endocytic machinery and high abundance of outward-looking molecules that can be used as receptors. At the same time, disruption of the rafts' functional capacity, achieved by the pathogens through a number of various means, impairs the ability of the host to generate immune response, thus helping pathogen to thrive. Pathogens cannot synthesize cholesterol, and salvaging host cholesterol helps pathogens build advanced cholesterol-containing membranes and assembly platforms. Impact on cholesterol metabolism is not limited to the infected cells; proteins and microRNAs secreted by infected cells affect lipid metabolism systemically. Given an essential role that host cholesterol metabolism plays in pathogen development, targeting this interaction may be a viable strategy to fight infections, as well as metabolic complications of the infections.

  1. Potentially pathogenic, pathogenic, and allergenic moulds in the urban soils

    Directory of Open Access Journals (Sweden)

    Đukić Dragutin A.

    2011-01-01

    Full Text Available The dynamics of soil mould populations that can compromise the human immune system was evaluated in experimental plots located at different distances (100, 300, 500, 700 and 900 m from the main source of pollution - the Podgorica Aluminum Plant. Soil samples were collected in July and October 2008 from three different plot zones at a depth of 0-10 cm. The count of potentially pathogenic, keratinolytic and allergenic (melaninogenic moulds was assessed, which can significantly contribute to both diagnosis and prophylaxis. The count of medically important moulds was higher in the urban soil than in the unpolluted (control soil. Their count decreased with increasing distance from the main pollution source (PAP. Their abundance in the soil was considerably higher in autumn than in spring.

  2. Genetic characteristics and pathogenic mechanisms of periodontal pathogens.

    Science.gov (United States)

    Amano, A; Chen, C; Honma, K; Li, C; Settem, R P; Sharma, A

    2014-05-01

    Periodontal disease is caused by a group of bacteria that utilize a variety of strategies and molecular mechanisms to evade or overcome host defenses. Recent research has uncovered new evidence illuminating interesting aspects of the virulence of these bacteria and their genomic variability. This paper summarizes some of the strategies utilized by the major species - Aggregatibacter actinomycetemcomitans, Tannerella forsythia, Treponema denticola, and Porphyromonas gingivalis - implicated in the pathogenesis of periodontal disease. Whole-genome sequencing of 14 diverse A. actinomycetemcomitans strains has revealed variations in their genetic content (ranging between 0.4% and 19.5%) and organization. Strikingly, isolates from human periodontal sites showed no genomic changes during persistent colonization. T. forsythia manipulates the cytokine responses of macrophages and monocytes through its surface glycosylation. Studies have revealed that bacterial surface-expressed O-linked glycans modulate T-cell responses during periodontal inflammation. Periodontal pathogens belonging to the "red complex" consortium express neuraminidases, which enables them to scavenge sialic acid from host glycoconjugates. Analysis of recent data has demonstrated that the cleaved sialic acid acts as an important nutrient for bacterial growth and a molecule for the decoration of bacteria surfaces to help evade the host immune attack. In addition, bacterial entry into host cells is also an important prerequisite for the lifestyle of periodontal pathogens such as P. gingivalis. Studies have shown that, after its entry into the cell, this bacterium uses multiple sorting pathways destined for autophagy, lysosomes, or recycling pathways. In addition, P. gingivalis releases outer membrane vesicles which enter cells via endocytosis and cause cellular functional impairment.

  3. Mucosal immunity to pathogenic intestinal bacteria.

    Science.gov (United States)

    Perez-Lopez, Araceli; Behnsen, Judith; Nuccio, Sean-Paul; Raffatellu, Manuela

    2016-03-01

    The intestinal mucosa is a particularly dynamic environment in which the host constantly interacts with trillions of commensal microorganisms, known as the microbiota, and periodically interacts with pathogens of diverse nature. In this Review, we discuss how mucosal immunity is controlled in response to enteric bacterial pathogens, with a focus on the species that cause morbidity and mortality in humans. We explain how the microbiota can shape the immune response to pathogenic bacteria, and we detail innate and adaptive immune mechanisms that drive protective immunity against these pathogens. The vast diversity of the microbiota, pathogens and immune responses encountered in the intestines precludes discussion of all of the relevant players in this Review. Instead, we aim to provide a representative overview of how the intestinal immune system responds to pathogenic bacteria.

  4. Heme Synthesis and Acquisition in Bacterial Pathogens

    OpenAIRE

    Choby, Jacob E.; Skaar, Eric P.

    2016-01-01

    Bacterial pathogens require the iron-containing cofactor heme to cause disease. Heme is essential to the function of hemoproteins, which are involved in energy generation by the electron transport chain, detoxification of host immune effectors, and other processes. During infection, bacterial pathogens must synthesize heme or acquire heme from the host; however, host heme is sequestered in high-affinity hemoproteins. Pathogens have evolved elaborate strategies to acquire heme from host source...

  5. The Candida Pathogenic Species Complex

    Science.gov (United States)

    Turner, Siobhán A.; Butler, Geraldine

    2014-01-01

    Candida species are the most common causes of fungal infection. Approximately 90% of infections are caused by five species: Candida albicans, Candida glabrata, Candida tropicalis, Candida parapsilosis, and Candida krusei. Three (C. albicans, C. tropicalis, and C. parapsilosis) belong to the CTG clade, in which the CTG codon is translated as serine and not leucine. C. albicans remains the most commonly isolated but is decreasing relative to the other species. The increasing incidence of C. glabrata is related to its reduced susceptibility to azole drugs. Genome analysis suggests that virulence in the CTG clade is associated with expansion of gene families, particularly of cell wall genes. Similar independent processes took place in the C. glabrata species group. Gene loss and expansion in an ancestor of C. glabrata may have resulted in preadaptations that enabled pathogenicity. PMID:25183855

  6. Land application of sewage sludge: Pathogen issues

    International Nuclear Information System (INIS)

    Chang, A.C.

    1997-01-01

    Diseases transmitted via the faecal-oral exposure route cause severe gastroenteric disorders, and large numbers of causative organisms are discharged with the faecal matter of infected individuals. For this reason, pathogenic bacteria, viruses, protozoa, or helminths, are always found in sewage sludge. If not properly treated for use in agriculture, sludge can be a source of pathogenic contamination. Radiation is an attractive method to reduce the numbers of microorganisms in sewage sludge. Routine examination for pathogens is not practised nor recommended because complicated and costly procedures are involved. Instead, an indicator organism is usually assayed and enumerated. In this paper, methods are discussed for the investigation of pathogens in sewage sludge. (author)

  7. Ammonium-induced inhibition of ammonium-starved Nitrosomonas europaea cells in soil and sand slurries

    NARCIS (Netherlands)

    Gerards, S.; Duyts, H.; Laanbroek, H.J.

    1998-01-01

    Ammonia-oxidising bacteria are poor competitors for limiting amounts of ammonium. Hence, starvation for ammonium seems to be the regular condition for these bacteria in natural environments. Long-term survival in the absence of ammonium will be dependent on the ability to maintain large population

  8. Ammonium-induced impairment of axonal growth is prevented through glial creatine.

    OpenAIRE

    Braissant, O.; Henry, H.; Villard, A.M.; Zurich, M.G.; Loup, M.; Eilers, B.; Parlascino, G.; Matter, E.; Boulat, O.; Honegger, P.; Bachmann, C.

    2002-01-01

    Hyperammonemia in neonates and infants affects brain development and causes mental retardation. We report that ammonium impaired cholinergic axonal growth and altered localization and phosphorylation of intermediate neurofilament protein in rat reaggregated brain cell primary cultures. This effect was restricted to the phase of early maturation but did not occur after synaptogenesis. Exposure to NH4Cl decreased intracellular creatine, phosphocreatine, and ADP. We demonstrate that creatine cot...

  9. Comparative genome analysis of pathogenic and non-pathogenic Clavibacter strains reveals adaptations to their lifestyle

    OpenAIRE

    Załuga, Joanna; Stragier, Pieter; Baeyen, Steve; Haegeman, Annelies; Van Vaerenbergh, Johan; Maes, Martine; De Vos, Paul

    2014-01-01

    Background The genus Clavibacter harbors economically important plant pathogens infecting agricultural crops such as potato and tomato. Although the vast majority of Clavibacter strains are pathogenic, there is an increasing number of non-pathogenic isolates reported. Non-pathogenic Clavibacter strains isolated from tomato seeds are particularly problematic because they affect the current detection and identification tests for Clavibacter michiganensis subsp. michiganensis (Cmm), which is reg...

  10. Targeting of the hydrophobic metabolome by pathogens.

    Science.gov (United States)

    Helms, J Bernd; Kaloyanova, Dora V; Strating, Jeroen R P; van Hellemond, Jaap J; van der Schaar, Hilde M; Tielens, Aloysius G M; van Kuppeveld, Frank J M; Brouwers, Jos F

    2015-05-01

    The hydrophobic molecules of the metabolome - also named the lipidome - constitute a major part of the entire metabolome. Novel technologies show the existence of a staggering number of individual lipid species, the biological functions of which are, with the exception of only a few lipid species, unknown. Much can be learned from pathogens that have evolved to take advantage of the complexity of the lipidome to escape the immune system of the host organism and to allow their survival and replication. Different types of pathogens target different lipids as shown in interaction maps, allowing visualization of differences between different types of pathogens. Bacterial and viral pathogens target predominantly structural and signaling lipids to alter the cellular phenotype of the host cell. Fungal and parasitic pathogens have complex lipidomes themselves and target predominantly the release of polyunsaturated fatty acids from the host cell lipidome, resulting in the generation of eicosanoids by either the host cell or the pathogen. Thus, whereas viruses and bacteria induce predominantly alterations in lipid metabolites at the host cell level, eukaryotic pathogens focus on interference with lipid metabolites affecting systemic inflammatory reactions that are part of the immune system. A better understanding of the interplay between host-pathogen interactions will not only help elucidate the fundamental role of lipid species in cellular physiology, but will also aid in the generation of novel therapeutic drugs. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Population genomics of fungal and oomycete pathogens

    Science.gov (United States)

    We are entering a new era in plant pathology where whole-genome sequences of many individuals of a pathogen species are becoming readily available. This era of pathogen population genomics will provide new opportunities and challenges, requiring new computational and analytical tools. Population gen...

  12. Immunity to plant pathogens and iron homeostasis.

    Science.gov (United States)

    Aznar, Aude; Chen, Nicolas W G; Thomine, Sebastien; Dellagi, Alia

    2015-11-01

    Iron is essential for metabolic processes in most living organisms. Pathogens and their hosts often compete for the acquisition of this nutrient. However, iron can catalyze the formation of deleterious reactive oxygen species. Hosts may use iron to increase local oxidative stress in defense responses against pathogens. Due to this duality, iron plays a complex role in plant-pathogen interactions. Plant defenses against pathogens and plant response to iron deficiency share several features, such as secretion of phenolic compounds, and use common hormone signaling pathways. Moreover, fine tuning of iron localization during infection involves genes coding iron transport and iron storage proteins, which have been shown to contribute to immunity. The influence of the plant iron status on the outcome of a given pathogen attack is strongly dependent on the nature of the pathogen infection strategy and on the host species. Microbial siderophores emerged as important factors as they have the ability to trigger plant defense responses. Depending on the plant species, siderophore perception can be mediated by their strong iron scavenging capacity or possibly via specific recognition as pathogen associated molecular patterns. This review highlights that iron has a key role in several plant-pathogen interactions by modulating immunity. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  13. Bacterial reproductive pathogens of cats and dogs.

    Science.gov (United States)

    Graham, Elizabeth M; Taylor, David J

    2012-05-01

    With the notable exception of Brucella canis, exogenous bacterial pathogens are uncommon causes of reproductive disease in cats and dogs. Most bacterial reproductive infections are endogenous, and predisposing factors for infection are important. This article reviews the etiology, pathogenesis, clinical presentation, diagnosis, treatment, and public health significance of bacterial reproductive pathogens in cats and dogs.

  14. Digital PCR for detection of citrus pathogens

    Science.gov (United States)

    Citrus trees are often infected with multiple pathogens of economic importance, especially those with insect or mite vectors. Real-time/quantitative PCR (qPCR) has been used for high-throughput detection and relative quantification of pathogens; however, target reference or standards are required. I...

  15. Occurrence of root parsley pathogens inhabiting seeds

    Directory of Open Access Journals (Sweden)

    Bogdan Nowicki

    2013-12-01

    Full Text Available The studies on root parsley pathogens inhabiting seeds were conducted during 1981-1988 and in 1993. Filter paper method with prefreezing and keeping under light was used. Each test sample comprised 500 seeds. Pathogenicity of collected fungal isolates was tested following two laboratory methods. 238 seed samples were studied. 18 fungal species were found but only 7 proved to be important pathogens of root parsley. The most common inhabitants of root parsley seeds were Alternaria spp. A.allernata occurred on 74,8% of seeds but only a few isolates showed to be slightly pathogenic while A.petroselini and A.radicina were higly pathogenic and inhabited 11,4 and 4,2% of seeds, respectively. The second group of important pathogens were species of Fusarium found on 3,9% of seeds. F.avenaceum dominated as it comprised 48% of Fusarium isolates, the next were as follow: F.culmorum - 20%, F.equiseti - 15%, F.solani - 8%, F.oxysporum - 7% and F.dimerum -2%. Some fungi like Botrytis cinerea, Septoria petroselini and Phoma spp. inhabited low number of seeds, respectively O,4; 0,5 and 0,8%, but they were highly pathogenic to root parsley. The fungi: Bipolaris sorokiniana, Drechslera biseptata, Stemphylium botryosum and Ulocludium consortiale showed slight pathogenicity. They were isolated from 3,8% of seeds.

  16. 77 FR 34783 - Highly Pathogenic Avian Influenza

    Science.gov (United States)

    2012-06-12

    ... [Docket No. APHIS-2006-0074] RIN 0579-AC36 Highly Pathogenic Avian Influenza AGENCY: Animal and Plant... regions where any subtype of highly pathogenic avian influenza (HPAI) is considered to exist. The interim... avian influenza (HPAI). On January 24, 2011, we published in the Federal Register (76 FR 4046-4056...

  17. THE OCCURRENCE, GROWTH AND CONTROL OF PATHOGENS ...

    African Journals Online (AJOL)

    Fermented foods have many advantageous attributes such as improved nutritional value and safety against bacterial pathogens. These foods are also important for weaning purposes and hence play a role in protecting infants against foodborne diseases. However, pathogens have been isolated from some fermented foods ...

  18. Tracing pathogens in the food chain

    NARCIS (Netherlands)

    Brul, S.; Fratamico, P.M.; McMeekin, T.A.

    2010-01-01

    Successful methods for the detection and investigation of outbreaks of foodborne disease are essential for ensuring consumer safety. Increased understanding of the transmission of pathogens in food chains will also assist efforts to safeguard public health. Tracing pathogens in the food chain

  19. Arthropods vector grapevine trunk disease pathogens.

    Science.gov (United States)

    Moyo, P; Allsopp, E; Roets, F; Mostert, L; Halleen, F

    2014-10-01

    Arthropod-mediated dispersal of pathogens is known in many cropping systems but has never been demonstrated for grapevine trunk disease pathogens. Arthropods from vineyards were screened for the presence of pathogens associated with Petri disease and esca using cultural and molecular techniques. The ability of the most abundant pathogen-carrying species to inoculate healthy grapevine vascular tissues was also determined. Millipedes and ants were allowed to associate with a DsRed- Express-transformed Phaeomoniella chlamydospora, after which they were exposed to freshly pruned healthy grapevines under controlled conditions and wounds were monitored for subsequent infection. In addition, the possibility of millipede excreta, commonly found on pruning wounds in the field, to act as inoculum source was determined. A diverse arthropod fauna was associated with declining grapevines and many of these carried trunk disease pathogens. However, spiders, the ant Crematogaster peringueyi, and the millipede Ommattoiulus moreleti were the most abundant pathogen carriers. The ant and millipede species fed on pruning wound sap and effectively transmitted trunk disease pathogens. Millipede excreta contained viable spores of Phaeomoniella chlamydospora and may serve as an inoculum source. Numerous arthropods, including beneficial predators, are potential vectors of grapevine trunk disease pathogens. Our results highlight the need for an integrated approach, including targeted management of ants and millipedes at the time of pruning, to limit the spread of grapevine trunk diseases.

  20. Pathogens' toolbox to manipulate human complement.

    Science.gov (United States)

    Fernández, Francisco J; Gómez, Sara; Vega, M Cristina

    2017-12-14

    The surveillance and pathogen fighting functions of the complement system have evolved to protect mammals from life-threatening infections. In turn, pathogens have developed complex molecular mechanisms to subvert, divert and evade the effector functions of the complement. The study of complement immunoevasion by pathogens sheds light on their infection drivers, knowledge that is essential to implement therapies. At the same time, complement evasion also acts as a discovery ground that reveals important aspects of how complement works under physiological conditions. In recent years, complex interrelationships between infection insults and the onset of autoimmune and complement dysregulation diseases have led to propose that encounters with pathogens can act as triggering factors for disease. The correct management of these diseases involves the recognition of their triggering factors and the development and administration of complement-associated molecular therapies. Even more recently, unsuspected proteins from pathogens have been shown to possess moonlighting functions as virulence factors, raising the possibility that behind the first line of virulence factors there be many more pathogen proteins playing secondary, helping and supporting roles for the pathogen to successfully establish infections. In an era where antibiotics have a progressively reduced effect on the management and control of infectious diseases worldwide, knowledge on the mechanisms of pathogenic invasion and evasion look more necessary and pressing than ever. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Heme Synthesis and Acquisition in Bacterial Pathogens.

    Science.gov (United States)

    Choby, Jacob E; Skaar, Eric P

    2016-08-28

    Bacterial pathogens require the iron-containing cofactor heme to cause disease. Heme is essential to the function of hemoproteins, which are involved in energy generation by the electron transport chain, detoxification of host immune effectors, and other processes. During infection, bacterial pathogens must synthesize heme or acquire heme from the host; however, host heme is sequestered in high-affinity hemoproteins. Pathogens have evolved elaborate strategies to acquire heme from host sources, particularly hemoglobin, and both heme acquisition and synthesis are important for pathogenesis. Paradoxically, excess heme is toxic to bacteria and pathogens must rely on heme detoxification strategies. Heme is a key nutrient in the struggle for survival between host and pathogen, and its study has offered significant insight into the molecular mechanisms of bacterial pathogenesis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Pathogenic mechanisms of intracellular bacteria.

    Science.gov (United States)

    Niller, Hans Helmut; Masa, Roland; Venkei, Annamária; Mészáros, Sándor; Minarovits, Janos

    2017-06-01

    We wished to overview recent data on a subset of epigenetic changes elicited by intracellular bacteria in human cells. Reprogramming the gene expression pattern of various host cells may facilitate bacterial growth, survival, and spread. DNA-(cytosine C5)-methyltransferases of Mycoplasma hyorhinis targeting cytosine-phosphate-guanine (CpG) dinucleotides and a Mycobacterium tuberculosis methyltransferase targeting non-CpG sites methylated the host cell DNA and altered the pattern of gene expression. Gene silencing by CpG methylation and histone deacetylation, mediated by cellular enzymes, also occurred in M. tuberculosis-infected macrophages. M. tuberculosis elicited cell type-specific epigenetic changes: it caused increased DNA methylation in macrophages, but induced demethylation, deposition of euchromatic histone marks and activation of immune-related genes in dendritic cells. A secreted transposase of Acinetobacter baumannii silenced a cellular gene, whereas Mycobacterium leprae altered the epigenotype, phenotype, and fate of infected Schwann cells. The 'keystone pathogen' oral bacterium Porphyromonas gingivalis induced local DNA methylation and increased the level of histone acetylation in host cells. These epigenetic changes at the biofilm-gingiva interface may contribute to the development of periodontitis. Epigenetic regulators produced by intracellular bacteria alter the epigenotype and gene expression pattern of host cells and play an important role in pathogenesis.

  3. The evolution of pathogenic trypanosomes

    Directory of Open Access Journals (Sweden)

    Jamie R. Stevens

    Full Text Available In the absence of a fossil record, the evolution of protozoa has until recently largely remained a matter for speculation. However, advances in molecular methods and phylogenetic analysis are now allowing interpretation of the "history written in the genes". This review focuses on recent progress in reconstruction of trypanosome phylogeny based on molecular data from ribosomal RNA, the miniexon and protein-coding genes. Sufficient data have now been gathered to demonstrate unequivocally that trypanosomes are monophyletic; the phylogenetic trees derived can serve as a framework to reinterpret the biology, taxonomy and present day distribution of trypanosome species, providing insights into the coevolution of trypanosomes with their vertebrate hosts and vectors. Different methods of dating the divergence of trypanosome lineages give rise to radically different evolutionary scenarios and these are reviewed. In particular, the use of one such biogeographically based approach provides new insights into the coevolution of the pathogens, Trypanosoma brucei and Trypanosoma cruzi, with their human hosts and the history of the diseases with which they are associated.

  4. Quorum Sensing of Periodontal Pathogens

    Directory of Open Access Journals (Sweden)

    Darije Plančak

    2015-01-01

    Full Text Available The term ‘quorum sensing’ describes intercellular bacterial communication which regulates bacterial gene expression according to population cell density. Bacteria produce and secrete small molecules, named autoinducers, into the intercellular space. The concentration of these molecules increases as a function of population cell density. Once the concentration of the stimulatory threshold is reached, alteration in gene expression occurs. Gram-positive and Gram-negative bacteria possess different types of quorum sensing systems. Canonical LuxI/R-type/acyl homoserine lactone mediated quorum sensing system is the best studied quorum sensing circuit and is described in Gram-negative bacteria which employ it for inter-species communication mostly. Grampositive bacteria possess a peptide-mediated quorum sensing system. Bacteria can communicate within their own species (intra-species but also between species (inter-species, for which they employ an autoinducer-2 quorum sensing system which is called the universal language of the bacteria. Periodontal pathogenic bacteria possess AI-2 quorum sensing systems. It is known that they use it for regulation of biofilm formation, iron uptake, stress response and virulence factor expression. A better understanding of bacterial communication mechanisms will allow the targeting of quorum sensing with quorum sensing inhibitors to prevent and control disease.

  5. Algae as reservoirs for coral pathogens.

    Directory of Open Access Journals (Sweden)

    Michael J Sweet

    Full Text Available Benthic algae are associated with coral death in the form of stress and disease. It's been proposed that they release exudates, which facilitate invasion of potentially pathogenic microbes at the coral-algal interface, resulting in coral disease. However, the original source of these pathogens remains unknown. This study examined the ability of benthic algae to act as reservoirs of coral pathogens by characterizing surface associated microbes associated with major Caribbean and Indo-Pacific algal species/types and by comparing them to potential pathogens of two dominant coral diseases: White Syndrome (WS in the Indo-Pacific and Yellow Band Disease (YBD in the Caribbean. Coral and algal sampling was conducted simultaneously at the same sites to avoid spatial effects. Potential pathogens were defined as those absent or rare in healthy corals, increasing in abundance in healthy tissues adjacent to a disease lesion, and dominant in disease lesions. Potentially pathogenic bacteria were detected in both WS and YBD and were also present within the majority of algal species/types (54 and 100% for WS and YBD respectively. Pathogenic ciliates were associated only with WS and not YBD lesions and these were also present in 36% of the Indo-Pacific algal species. Although potential pathogens were associated with many algal species, their presence was inconsistent among replicate algal samples and detection rates were relatively low, suggestive of low density and occurrence. At the community level, coral-associated microbes irrespective of the health of their host differed from algal-associated microbes, supporting that algae and corals have distinctive microbial communities associated with their tissue. We conclude that benthic algae are common reservoirs for a variety of different potential coral pathogens. However, algal-associated microbes alone are unlikely to cause coral death. Initial damage or stress to the coral via other competitive mechanisms is

  6. Comparative genome analysis of pathogenic and non-pathogenic Clavibacter strains reveals adaptations to their lifestyle.

    Science.gov (United States)

    Załuga, Joanna; Stragier, Pieter; Baeyen, Steve; Haegeman, Annelies; Van Vaerenbergh, Johan; Maes, Martine; De Vos, Paul

    2014-05-22

    The genus Clavibacter harbors economically important plant pathogens infecting agricultural crops such as potato and tomato. Although the vast majority of Clavibacter strains are pathogenic, there is an increasing number of non-pathogenic isolates reported. Non-pathogenic Clavibacter strains isolated from tomato seeds are particularly problematic because they affect the current detection and identification tests for Clavibacter michiganensis subsp. michiganensis (Cmm), which is regulated with a zero tolerance in tomato seed. Their misidentification as pathogenic Cmm hampers a clear judgment on the seed quality and health. To get more insight in the genetic features linked to the lifestyle of these bacteria, a whole-genome sequence of the tomato seed-borne non-pathogenic Clavibacter LMG 26808 was determined. To gain a better understanding of the molecular determinants of pathogenicity, the genome sequence of LMG 26808 was compared with that of the pathogenic Cmm strain (NCPPB 382). The comparative analysis revealed that LMG 26808 does not contain plasmids pCM1 and pCM2 and also lacks the majority of important virulence factors described so far for pathogenic Cmm. This explains its apparent non-pathogenic nature in tomato plants. Moreover, the genome analysis of LMG 26808 detected sequences from a plasmid originating from a member of Enterobacteriaceae/Klebsiella relative. Genes received that way and coding for antibiotic resistance may provide a competitive advantage for survival of LMG 26808 in its ecological niche. Genetically, LMG 26808 was the most similar to the pathogenic Cmm NCPPB 382 but contained more mobile genetic elements. The genome of this non-pathogenic Clavibacter strain contained also a high number of transporters and regulatory genes. The genome sequence of the non-pathogenic Clavibacter strain LMG 26808 and the comparative analyses with other pathogenic Clavibacter strains provided a better understanding of the genetic bases of virulence and

  7. Efferocytosis of Pathogen-Infected Cells

    Directory of Open Access Journals (Sweden)

    Niloofar Karaji

    2017-12-01

    Full Text Available The prompt and efficient clearance of unwanted and abnormal cells by phagocytes is termed efferocytosis and is crucial for organism development, maintenance of tissue homeostasis, and regulation of the immune system. Dying cells are recognized by phagocytes through pathways initiated via “find me” signals, recognition via “eat me” signals and down-modulation of regulatory “don’t eat me” signals. Pathogen infection may trigger cell death that drives phagocytic clearance in an immunologically silent, or pro-inflammatory manner, depending on the mode of cell death. In many cases, efferocytosis is a mechanism for eliminating pathogens and pathogen-infected cells; however, some pathogens have subverted this process and use efferocytic mechanisms to avoid innate immune detection and assist phagocyte infection. In parallel, phagocytes can integrate signals received from infected dying cells to elicit the most appropriate effector response against the infecting pathogen. This review focuses on pathogen-induced cell death signals that drive infected cell recognition and uptake by phagocytes, and the outcomes for the infected target cell, the phagocyte, the pathogen and the host.

  8. Waterborne Pathogens: Detection Methods and Challenges

    Directory of Open Access Journals (Sweden)

    Flor Yazmín Ramírez-Castillo

    2015-05-01

    Full Text Available Waterborne pathogens and related diseases are a major public health concern worldwide, not only by the morbidity and mortality that they cause, but by the high cost that represents their prevention and treatment. These diseases are directly related to environmental deterioration and pollution. Despite the continued efforts to maintain water safety, waterborne outbreaks are still reported globally. Proper assessment of pathogens on water and water quality monitoring are key factors for decision-making regarding water distribution systems’ infrastructure, the choice of best water treatment and prevention waterborne outbreaks. Powerful, sensitive and reproducible diagnostic tools are developed to monitor pathogen contamination in water and be able to detect not only cultivable pathogens but also to detect the occurrence of viable but non-culturable microorganisms as well as the presence of pathogens on biofilms. Quantitative microbial risk assessment (QMRA is a helpful tool to evaluate the scenarios for pathogen contamination that involve surveillance, detection methods, analysis and decision-making. This review aims to present a research outlook on waterborne outbreaks that have occurred in recent years. This review also focuses in the main molecular techniques for detection of waterborne pathogens and the use of QMRA approach to protect public health.

  9. Laser inactivation of pathogenic viruses in water

    Science.gov (United States)

    Grishkanich, Alexander; Zhevlakov, Alexander; Kascheev, Sergey; Sidorov, Igor; Ruzankina, Julia; Yakovlev, Alexey; Mak, Andrey

    2016-03-01

    Currently there is a situation that makes it difficult to provide the population with quality drinking water for the sanitary-hygienic requirements. One of the urgent problems is the need for water disinfection. Since the emergence of microorganisms that are pathogens transmitted through water such as typhoid, cholera, etc. requires constant cleansing of waters against pathogenic bacteria. In the water treatment process is destroyed up to 98% of germs, but among the remaining can be pathogenic viruses, the destruction of which requires special handling. As a result, the conducted research the following methods have been proposed for combating harmful microorganisms: sterilization of water by laser radiation and using a UV lamp.

  10. A novel approach for differentiating pathogenic and non-pathogenic Leptospira based on molecular fingerprinting.

    Science.gov (United States)

    Xiao, Di; Zhang, Cuicai; Zhang, Huifang; Li, Xiuwen; Jiang, Xiugao; Zhang, Jianzhong

    2015-04-24

    Leptospirosis is a worldwide, deadly zoonotic disease. Pathogenic Leptospira causes leptospirosis. The rapid and accurate identification of pathogenic and non-pathogenic Leptospira strains is essential for appropriate therapeutic management and timely intervention for infection control. The molecular fingerprint is a simple and rapid alternative tool for microorganisms identification, which is based on matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). In this study, molecular fingerprint was performed to identify pathogenic strains of Leptospira. Phylogenetic analysis based on 16S rRNA gene sequences was used as the reference method. In addition, a label-free technique was used to reveal the different proteins of pathogenic or non-pathogenic Leptospira. A reference database was constructed using 30 Leptospira strains, including 16 pathogenic strains and 14 non-pathogenic strains. Two super reference spectra that were associated with pathogenicity were established. Overall, 33 Leptospira strains were used for validation, and 32 of 33 Leptospira strains could be identified on the species level and all the 33 could be classified as pathogenic or non-pathogenic. The super reference spectra and the major spectra projection (MSP) dendrogram correctly categorized the Leptospira strains into pathogenic and non-pathogenic groups, which was consistent with the 16S rRNA reference methods. Between the pathogenic and non-pathogenic strains, 108 proteins were differentially expressed. molecular fingerprint is an alternative to conventional molecular identification and can rapidly distinguish between pathogenic and non-pathogenic Leptospira strains. Therefore, molecular fingerprint may play an important role in the clinical diagnosis, treatment, surveillance, and tracking of epidemic outbreaks of leptospirosis. Leptospirosis is a worldwide zoonosis that is caused by spirochetes of the genus Leptospira. Leptospirosis is a serious zoonotic

  11. Pathogen reduction in sludges by irradiation

    International Nuclear Information System (INIS)

    Brandon, J.R.

    1978-01-01

    This paper presents results of pathogen inactivation programs being conducted in Belgium, Czechoslovakia, France, East Germany, West Germany, Hungary, Italy, The Netherlands, Poland, Spain, Sweden, Switzerland, the United Kingdom, and the United States

  12. Land application of sewage sludge: Pathogen issues

    Energy Technology Data Exchange (ETDEWEB)

    Chang, A C [Department of Soil and Environmental Sciences, Univ. of California at Riverside, Riverside, CA (United States)

    1997-10-01

    Diseases transmitted via the faecal-oral exposure route cause severe gastroenteric disorders, and large numbers of causative organisms are discharged with the faecal matter of infected individuals. For this reason, pathogenic bacteria, viruses, protozoa, or helminths, are always found in sewage sludge. If not properly treated for use in agriculture, sludge can be a source of pathogenic contamination. Radiation is an attractive method to reduce the numbers of microorganisms in sewage sludge. Routine examination for pathogens is not practised nor recommended because complicated and costly procedures are involved. Instead, an indicator organism is usually assayed and enumerated. In this paper, methods are discussed for the investigation of pathogens in sewage sludge. (author). 8 refs, 3 tabs.

  13. Genomes of foodborne and waterborne pathogens

    National Research Council Canada - National Science Library

    Fratamico, Pina M; Liu, Yanhong; Kathariou, Sophia

    2011-01-01

    ... of Pathogenic Vibrio cholerae * 85 Salvador Almagro-Moreno, Ronan A. Murphy, and E. Fidelma Boyd 8. Genomics of the Enteropathogenic Yersiniae * 101 Alan McNally, Nicholas R. Thomson, and Brendan W. ...

  14. Antibiotic resistance and pathogenicity factors in Staphylococcus ...

    Indian Academy of Sciences (India)

    know which endemic strains of S. aureus in dairy cattle ... Antibiotic resistance; cattle; mastitis; MRSA; pathogenic genes ... recommended by Clinical and Laboratory Standards Institute ...... fnbA, eno, hla and nuc, did not show any relation to.

  15. Exposure Control--OSHA's Bloodborne Pathogens Standard.

    Science.gov (United States)

    Granville, Mark F.

    1993-01-01

    Explains schools' responsibilities in complying with the Occupational Safety and Health Administration's (OSHA) Bloodborne Pathogens Standard. Describes exposure determination plan, protective equipment, housekeeping practices, labeling of waste, training employees, hepatitis B vaccinations, postexposure evaluation and medical follow-up, and…

  16. Persistence and drug tolerance in pathogenic yeast

    DEFF Research Database (Denmark)

    Bojsen, Rasmus Kenneth; Regenberg, Birgitte; Folkesson, Sven Anders

    2017-01-01

    In this review, we briefly summarize the current understanding of how fungal pathogens can persist antifungal treatment without heritable resistance mutations by forming tolerant persister cells. Fungal infections tolerant to antifungal treatment have become a major medical problem. One mechanism...

  17. Promotion and inhibition of mutation in pathogens

    Directory of Open Access Journals (Sweden)

    Maurice Samuel Devaraj

    2014-03-01

    Findings from this research may be used to prevent development of drug resistance, whether epigenetic or arising due to deoxyribonucleic acid (DNA modification, in several pathogens, especially Mycobacterium tuberculosis through the co-administration of adenosine along with antibiotic treatment.

  18. Modulation of pathogen recognition by autophagy

    Directory of Open Access Journals (Sweden)

    Ji Eun eOh

    2012-03-01

    Full Text Available Autophagy is an ancient biological process for maintaining cellular homeostasis by degradation of long-lived cytosolic proteins and organelles. Recent studies demonstrated that autophagy is availed by immune cells to regulate innate immunity. On the one hand, cells exert direct effector function by degrading intracellular pathogens; on the other hand, autophagy modulates pathogen recognition and downstream signaling for innate immune responses. Pathogen recognition via pattern recognition receptors induces autophagy. The function of phagocytic cells is enhanced by recruitment of autophagy-related proteins. Moreover, autophagy acts as a delivery system for viral replication complexes to migrate to the endosomal compartments where virus sensing occurs. In another case, key molecules of the autophagic pathway have been found to negatively regulate immune signaling, thus preventing aberrant activation of cytokine production and consequent immune responses. In this review, we focus on the recent advances in the role of autophagy in pathogen recognition and modulation of innate immune responses.

  19. Pathogen Causing Disease of Diagnosis PCR Tecnology

    OpenAIRE

    SEVİNDİK, Emre; KIR, A. Çağrı; BAŞKEMER, Kadir; UZUN, Veysel

    2013-01-01

    Polimerase chain reaction (PCR) with which, the development of recombinant DNA tecnology, a technique commonly used in field of moleculer biology and genetic. Duplication of the target DNA is provided with this technique without the need for cloning. Some fungus species, bacteria, viruses constitutent an important group of pathogenicity in human, animals and plants. There are routinely applied types of PCR in the detection of pathogens infections diseases. These Nested- PCR, Real- Time PCR, M...

  20. Adaptive value of sex in microbial pathogens.

    Science.gov (United States)

    Michod, Richard E; Bernstein, Harris; Nedelcu, Aurora M

    2008-05-01

    Explaining the adaptive value of sex is one of the great outstanding problems in biology. The challenge comes from the difficulty in identifying the benefits provided by sex, which must outweigh the substantial costs of sex. Here, we consider the adaptive value of sex in viruses, bacteria and fungi, and particularly the information available on the adaptive role of sex in pathogenic microorganisms. Our general theme is that the varied aspects of sex in pathogens illustrate the varied issues surrounding the evolution of sex generally. These include, the benefits of sex (in the short- and long-term), as well as the costs of sex (both to the host and to the pathogen). For the benefits of sex (that is, its adaptive value), we consider three hypotheses: (i) sex provides for effective and efficient recombinational repair of DNA damages, (ii) sex provides DNA for food, and (iii) sex produces variation and reduces genetic associations among alleles under selection. Although the evolution of sex in microbial pathogens illustrates these general issues, our paper is not a general review of theories for the evolution of sex in all organisms. Rather, we focus on the adaptive value of sex in microbial pathogens and conclude that in terms of short-term benefits, the DNA repair hypothesis has the most support and is the most generally applicable hypothesis in this group. In particular, recombinational repair of DNA damages may substantially benefit pathogens when challenged by the oxidative defenses of the host. However, in the long-term, sex may help get rid of mutations, increase the rate of adaptation of the population, and, in pathogens, may infrequently create new infective strains. An additional general issue about sex illustrated by pathogens is that some of the most interesting consequences of sex are not necessarily the reasons for which sex evolved. For example, antibiotic resistance may be transferred by bacterial sex, but this transfer is probably not the reason sex

  1. Identification of periodontal pathogens in atherosclerotic vessels

    DEFF Research Database (Denmark)

    Fiehn, Nils-Erik; Larsen, Tove; Christiansen, Natalia

    2005-01-01

    Epidemiological studies have shown that periodontitis may be associated with presence of atherosclerosis. DNA from periodontal pathogens has been detected in atherosclerotic lesions, but viable oral bacteria have not yet been isolated from atherosclerotic plaques. The purpose of the present study...... was to determine if viable oral bacteria could be isolated from atherosclerotic lesions and if DNA from periodontal pathogens could be detected by use of polymerase chain reaction (PCR) techniques....

  2. The cuticle and plant defense to pathogens

    Directory of Open Access Journals (Sweden)

    Jean-Pierre eMetraux

    2014-06-01

    Full Text Available The cuticle provides a physical barrier against water loss and protects against irradiation, xenobiotics and pathogens. Components of the cuticle are perceived by invading fungi and activate developmental processes during pathogenesis. In addition, cuticle alterations of various types induce a syndrome of reactions that often results in resistance to necrotrophs. This article reviews the current knowledge on the role of the cuticle in relation to the perception of pathogens and activation of defenses.

  3. Adenoid Reservoir for Pathogenic Biofilm Bacteria▿

    Science.gov (United States)

    Nistico, L.; Kreft, R.; Gieseke, A.; Coticchia, J. M.; Burrows, A.; Khampang, P.; Liu, Y.; Kerschner, J. E.; Post, J. C.; Lonergan, S.; Sampath, R.; Hu, F. Z.; Ehrlich, G. D.; Stoodley, P.; Hall-Stoodley, L.

    2011-01-01

    Biofilms of pathogenic bacteria are present on the middle ear mucosa of children with chronic otitis media (COM) and may contribute to the persistence of pathogens and the recalcitrance of COM to antibiotic treatment. Controlled studies indicate that adenoidectomy is effective in the treatment of COM, suggesting that the adenoids may act as a reservoir for COM pathogens. To investigate the bacterial community in the adenoid, samples were obtained from 35 children undergoing adenoidectomy for chronic OM or obstructive sleep apnea. We used a novel, culture-independent molecular diagnostic methodology, followed by confocal microscopy, to investigate the in situ distribution and organization of pathogens in the adenoids to determine whether pathogenic bacteria exhibited criteria characteristic of biofilms. The Ibis T5000 Universal Biosensor System was used to interrogate the extent of the microbial diversity within adenoid biopsy specimens. Using a suite of 16 broad-range bacterial primers, we demonstrated that adenoids from both diagnostic groups were colonized with polymicrobial biofilms. Haemophilus influenzae was present in more adenoids from the COM group (P = 0.005), but there was no significant difference between the two patient groups for Streptococcus pneumoniae or Staphylococcus aureus. Fluorescence in situ hybridization, lectin binding, and the use of antibodies specific for host epithelial cells demonstrated that pathogens were aggregated, surrounded by a carbohydrate matrix, and localized on and within the epithelial cell surface, which is consistent with criteria for bacterial biofilms. PMID:21307211

  4. Regulatory T cells and immunity to pathogens.

    Science.gov (United States)

    Rouse, Barry T; Suvas, Susmit

    2007-09-01

    Immune responses to pathogens are modulated by one or more types of cells that perform a regulatory function. Some cells with this function, such as CD4+ Foxp3+ natural regulatory T cells (nTreg), pre-exist prior to infections whereas others may be induced as a consequence of infection (adaptive Treg). With pathogens that have a complex pathogenesis, multiple types of regulatory cells could influence the outcome. One major property of Treg is to help minimize collateral tissue damage that can occur during immune reactions to a chronic infection. The consequence is less damage to the host but in such situations the pathogen is likely to establish persistence. In some cases, a fine balance is established between Treg responses, effector components of immunity and the pathogen. Treg responses to pathogens may also act to hamper the efficacy of immune control. This review discusses these issues as well as the likely mechanisms by which various pathogens can signal the participation of Treg during infection.

  5. Sexual Reproduction of Human Fungal Pathogens

    Science.gov (United States)

    Heitman, Joseph; Carter, Dee A.; Dyer, Paul S.; Soll, David R.

    2014-01-01

    We review here recent advances in our understanding of sexual reproduction in fungal pathogens that commonly infect humans, including Candida albicans, Cryptococcus neoformans/gattii, and Aspergillus fumigatus. Where appropriate or relevant, we introduce findings on other species associated with human infections. In particular, we focus on rapid advances involving genetic, genomic, and population genetic approaches that have reshaped our view of how fungal pathogens evolve. Rather than being asexual, mitotic, and largely clonal, as was thought to be prevalent as recently as a decade ago, we now appreciate that the vast majority of pathogenic fungi have retained extant sexual, or parasexual, cycles. In some examples, sexual and parasexual unions of pathogenic fungi involve closely related individuals, generating diversity in the population but with more restricted recombination than expected from fertile, sexual, outcrossing and recombining populations. In other cases, species and isolates participate in global outcrossing populations with the capacity for considerable levels of gene flow. These findings illustrate general principles of eukaryotic pathogen emergence with relevance for other fungi, parasitic eukaryotic pathogens, and both unicellular and multicellular eukaryotic organisms. PMID:25085958

  6. Pathogenicity of Human ST23 Streptococcus agalactiae to Fish and Genomic Comparison of Pathogenic and Non-pathogenic Isolates

    Directory of Open Access Journals (Sweden)

    Rui Wang

    2017-10-01

    Full Text Available Streptococcus agalactiae, or Group B Streptococcus (GBS, is a major pathogen causing neonatal sepsis and meningitis, bovine mastitis, and fish meningoencephalitis. CC23, including its namesake ST23, is not only the predominant GBS strain derived from human and cattle, but also can infect a variety of homeothermic and poikilothermic species. However, it has never been characterized in fish. This study aimed to determine the pathogenicity of ST23 GBS to fish and explore the mechanisms causing the difference in the pathogenicity of ST23 GBS based on the genome analysis. Infection of tilapia with 10 human-derived ST23 GBS isolates caused tissue damage and the distribution of pathogens within tissues. The mortality rate of infection was ranged from 76 to 100%, and it was shown that the mortality rate caused by only three human isolates had statistically significant difference compared with fish-derived ST7 strain (P < 0.05, whereas the mortality caused by other seven human isolates did not show significant difference compared with fish-derived ST7 strain. The genome comparison and prophage analysis showed that the major genome difference between virulent and non-virulent ST23 GBS was attributed to the different prophage sequences. The prophage in the P1 region contained about 43% GC and encoded 28–39 proteins, which can mediate the acquisition of YafQ/DinJ structure for GBS by phage recombination. YafQ/DinJ belongs to one of the bacterial toxin–antitoxin (TA systems and allows cells to cope with stress. The ST23 GBS strains carrying this prophage were not pathogenic to tilapia, but the strains without the prophage or carrying the pophage that had gene mutation or deletion, especially the deletion of YafQ/DinJ structure, were highly pathogenic to tilapia. In conclusion, human ST23 GBS is highly pathogenic to fish, which may be related to the phage recombination.

  7. Pathogenicity and Host Range of Pathogen Causing Black Raspberry (Rubus coreanus) Anthracnose in Korea

    OpenAIRE

    Uh Seong Jeong; Ju Hee Kim; Ki Kwon Lee; Seong Soo Cheong; Wang Hyu Lee

    2013-01-01

    The strains of Colletotrichum gloeosporioides, C. coccodes, C. acutatum isolated from black raspberry werepathogenic to apple and strawberry after dropping inoculation, but showed weak pathogenicity in hot-pepperand tomato. The anthracnose pathogens of C. gloeosporioides, C. orbiculare, C. acutatum isolated from apple,hot-pepper and pumpkin showed pathogenicity in black raspberry. Moreover, the anthracnose pathogensisolated from apple caused disease symptoms in non-wounded inoculation.

  8. Electrochemical Methodologies for the Detection of Pathogens.

    Science.gov (United States)

    Amiri, Mandana; Bezaatpour, Abolfazl; Jafari, Hamed; Boukherroub, Rabah; Szunerits, Sabine

    2018-05-25

    Bacterial infections remain one of the principal causes of morbidity and mortality worldwide. The number of deaths due to infections is declining every year by only 1% with a forecast of 13 million deaths in 2050. Among the 1400 recognized human pathogens, the majority of infectious diseases is caused by just a few, about 20 pathogens only. While the development of vaccinations and novel antibacterial drugs and treatments are at the forefront of research, and strongly financially supported by policy makers, another manner to limit and control infectious outbreaks is targeting the development and implementation of early warning systems, which indicate qualitatively and quantitatively the presence of a pathogen. As toxin contaminated food and drink are a potential threat to human health and consequently have a significant socioeconomic impact worldwide, the detection of pathogenic bacteria remains not only a big scientific challenge but also a practical problem of enormous significance. Numerous analytical methods, including conventional culturing and staining techniques as well as molecular methods based on polymerase chain reaction amplification and immunological assays, have emerged over the years and are used to identify and quantify pathogenic agents. While being highly sensitive in most cases, these approaches are highly time, labor, and cost consuming, requiring trained personnel to perform the frequently complex assays. A great challenge in this field is therefore to develop rapid, sensitive, specific, and if possible miniaturized devices to validate the presence of pathogens in cost and time efficient manners. Electrochemical sensors are well accepted powerful tools for the detection of disease-related biomarkers and environmental and organic hazards. They have also found widespread interest in the last years for the detection of waterborne and foodborne pathogens due to their label free character and high sensitivity. This Review is focused on the current

  9. Pathogenicity island mobility and gene content.

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Kelly Porter

    2013-10-01

    Key goals towards national biosecurity include methods for analyzing pathogens, predicting their emergence, and developing countermeasures. These goals are served by studying bacterial genes that promote pathogenicity and the pathogenicity islands that mobilize them. Cyberinfrastructure promoting an island database advances this field and enables deeper bioinformatic analysis that may identify novel pathogenicity genes. New automated methods and rich visualizations were developed for identifying pathogenicity islands, based on the principle that islands occur sporadically among closely related strains. The chromosomally-ordered pan-genome organizes all genes from a clade of strains; gaps in this visualization indicate islands, and decorations of the gene matrix facilitate exploration of island gene functions. A %E2%80%9Clearned phyloblocks%E2%80%9D method was developed for automated island identification, that trains on the phylogenetic patterns of islands identified by other methods. Learned phyloblocks better defined termini of previously identified islands in multidrug-resistant Klebsiella pneumoniae ATCC BAA-2146, and found its only antibiotic resistance island.

  10. Deconstructing host-pathogen interactions in Drosophila

    Directory of Open Access Journals (Sweden)

    Ethan Bier

    2012-01-01

    Full Text Available Many of the cellular mechanisms underlying host responses to pathogens have been well conserved during evolution. As a result, Drosophila can be used to deconstruct many of the key events in host-pathogen interactions by using a wealth of well-developed molecular and genetic tools. In this review, we aim to emphasize the great leverage provided by the suite of genomic and classical genetic approaches available in flies for decoding details of host-pathogen interactions; these findings can then be applied to studies in higher organisms. We first briefly summarize the general strategies by which Drosophila resists and responds to pathogens. We then focus on how recently developed genome-wide RNA interference (RNAi screens conducted in cells and flies, combined with classical genetic methods, have provided molecular insight into host-pathogen interactions, covering examples of bacteria, fungi and viruses. Finally, we discuss novel strategies for how flies can be used as a tool to examine how specific isolated virulence factors act on an intact host.

  11. PIML: the Pathogen Information Markup Language.

    Science.gov (United States)

    He, Yongqun; Vines, Richard R; Wattam, Alice R; Abramochkin, Georgiy V; Dickerman, Allan W; Eckart, J Dana; Sobral, Bruno W S

    2005-01-01

    A vast amount of information about human, animal and plant pathogens has been acquired, stored and displayed in varied formats through different resources, both electronically and otherwise. However, there is no community standard format for organizing this information or agreement on machine-readable format(s) for data exchange, thereby hampering interoperation efforts across information systems harboring such infectious disease data. The Pathogen Information Markup Language (PIML) is a free, open, XML-based format for representing pathogen information. XSLT-based visual presentations of valid PIML documents were developed and can be accessed through the PathInfo website or as part of the interoperable web services federation known as ToolBus/PathPort. Currently, detailed PIML documents are available for 21 pathogens deemed of high priority with regard to public health and national biological defense. A dynamic query system allows simple queries as well as comparisons among these pathogens. Continuing efforts are being taken to include other groups' supporting PIML and to develop more PIML documents. All the PIML-related information is accessible from http://www.vbi.vt.edu/pathport/pathinfo/

  12. Susceptibility of pathogenic and nonpathogenic Naegleria ssp

    International Nuclear Information System (INIS)

    Whiteman, L.Y.

    1988-01-01

    The susceptibility of four species of Naegleria amoebae to complement-mediated lysis was determined. The amoebicidal activity of normal human serum (NHS) and normal guinea pig serum (NGPS) for Naegleria amoebae was measured by an in vitro cytotoxicity assay. Release of radioactivity from amoebae labeled with 3 H-uridine and visual observation with a compound microscope were used as indices of lysis. Susceptibility or resistance to complement-mediated lysis in vitro correlated with the in vivo pathogenic potential. Nonpathogenic Naegleria amoebae were lysed at a faster rate and at higher cell concentrations than were pathogenic amoebae. Electrophoretic analysis of NHS incubated with pathogenic or nonpathogenic Naegleria spp. demonstrated that amoebae activate the complement cascade resulting in the production of C3 and C5 complement cleavage products. Treatment with papain or trypsin for 1 h, but not with sialidase, increase the susceptibility of highly pathogenic, mouse-passaged N. fowleri to lysis. Treatment with actinomycin D, cycloheximide or various protease inhibitors for 4 h did not increase susceptibility to lysis. Neither a repair process involving de novo protein synthesis nor a complement-inactivating protease appear to account for the increase resistance of N. fowleri amoebae to complement-mediated lysis. A binding study with 125 I radiolabeled C9 indicated that the terminal complement component does not remain stably bound to the membrane of pathogenic amoebae

  13. Regulatory Proteolysis in Arabidopsis-Pathogen Interactions.

    Science.gov (United States)

    Pogány, Miklós; Dankó, Tamás; Kámán-Tóth, Evelin; Schwarczinger, Ildikó; Bozsó, Zoltán

    2015-09-24

    Approximately two and a half percent of protein coding genes in Arabidopsis encode enzymes with known or putative proteolytic activity. Proteases possess not only common housekeeping functions by recycling nonfunctional proteins. By irreversibly cleaving other proteins, they regulate crucial developmental processes and control responses to environmental changes. Regulatory proteolysis is also indispensable in interactions between plants and their microbial pathogens. Proteolytic cleavage is simultaneously used both by plant cells, to recognize and inactivate invading pathogens, and by microbes, to overcome the immune system of the plant and successfully colonize host cells. In this review, we present available results on the group of proteases in the model plant Arabidopsis thaliana whose functions in microbial pathogenesis were confirmed. Pathogen-derived proteolytic factors are also discussed when they are involved in the cleavage of host metabolites. Considering the wealth of review papers available in the field of the ubiquitin-26S proteasome system results on the ubiquitin cascade are not presented. Arabidopsis and its pathogens are conferred with abundant sets of proteases. This review compiles a list of those that are apparently involved in an interaction between the plant and its pathogens, also presenting their molecular partners when available.

  14. Immune Evasion Strategies of Pathogens in Macrophages: the Potential for Limiting Pathogen Transmission.

    Science.gov (United States)

    Ren, Yuwei; Khan, Faheem Ahmed; Pandupuspitasari, Nuruliarizki Shinta; Zhang, Shujun

    2017-01-01

    Preventing pathogen transmission to a new host is of major interest to the immunologist and could benefit from a detailed investigation of pathogen immune evasion strategies. The first line of defense against pathogen invasion is provided by macrophages. When they sense pathogens, macrophages initiate signals to inflammatory and pro-inflammatory cytokines through pattern recognition receptors (PRRs) subsequently mediating phagocytosis and inflammation. The macrophage immune machinery classically includes two subsets: the activated M1 and the activated M2 that respond accordingly in diverse immune challenges. The lipid and glycogen metabolic pathways work together with the lysosome to help the mature phagosome to degrade and eliminate intracellular pathogens in macrophages. The viral evasion strategies are even more complex due to the interplay between autophagy and apoptosis. However, pathogens evolve several strategies to camouflage themselves against immune responses in order to ensure their survival, replication and transmission. These strategies include the muting of PRRs initiated inflammatory responses, attenuation of M1 and/or induction of M2 macrophages, suppression of autophago-lysosomal formation, interference with lipid and glycogen metabolism, and viral mediation of autophagy and apoptosis cross-talk to enhance viral replication. This review focuses on pathogen immune evasion methods and on the strategies used by the host against camouflaged pathogens.

  15. Priority setting of foodborne pathogens: disease burden and costs of selected enteric pathogens

    NARCIS (Netherlands)

    Kemmeren JM; Mangen MJJ; Duynhoven YTHP van; Havelaar AH; MGB

    2006-01-01

    Toxoplasmosis causes the highest disease burden among seven evaluated foodborne pathogens. This is the preliminary conclusion of a major study of the disease burden and related costs of foodborne pathogens. The other micro-organisms that were studied are Campylobacter spp., Salmonella spp.,

  16. Methods for detecting pathogens in the beef food chain: detecting particular pathogens

    Science.gov (United States)

    The main food-borne pathogens of concern in the beef food chain are Shiga toxin-producing Escherichia coli (STEC) and Salmonella spp.; however, the presence of other pathogens, including Listeria monocytogenes, Campylobacter spp., Clostridium spp., Bacillus cereus, and Mycobacterium avium subsp. par...

  17. Host-pathogen interactions and genome evolution in two generalist and specialist microsporidian pathogens of mosquitoes

    Science.gov (United States)

    The adaptation of two distantly related microsporidia to their mosquito hosts was investigated. Edhazardia aedis is a specialist pathogen that infects Aedes aegypti, the main vector of dengue and yellow fever arboviruses. Vavraia culicis is a generalist pathogen of several insects including Anophele...

  18. Insight of Genus Corynebacterium: Ascertaining the Role of Pathogenic and Non-pathogenic Species.

    Science.gov (United States)

    Oliveira, Alberto; Oliveira, Leticia C; Aburjaile, Flavia; Benevides, Leandro; Tiwari, Sandeep; Jamal, Syed B; Silva, Arthur; Figueiredo, Henrique C P; Ghosh, Preetam; Portela, Ricardo W; De Carvalho Azevedo, Vasco A; Wattam, Alice R

    2017-01-01

    This review gathers recent information about genomic and transcriptomic studies in the Corynebacterium genus, exploring, for example, prediction of pathogenicity islands and stress response in different pathogenic and non-pathogenic species. In addition, is described several phylogeny studies to Corynebacterium , exploring since the identification of species until biological speciation in one species belonging to the genus Corynebacterium . Important concepts associated with virulence highlighting the role of Pld protein and Tox gene. The adhesion, characteristic of virulence factor, was described using the sortase mechanism that is associated to anchorage to the cell wall. In addition, survival inside the host cell and some diseases, were too addressed for pathogenic corynebacteria, while important biochemical pathways and biotechnological applications retain the focus of this review for non-pathogenic corynebacteria. Concluding, this review broadly explores characteristics in genus Corynebacterium showing to have strong relevance inside the medical, veterinary, and biotechnology field.

  19. Serpin functions in host-pathogen interactions

    Directory of Open Access Journals (Sweden)

    Jialing Bao

    2018-04-01

    Full Text Available Serpins are a broadly distributed superfamily of protease inhibitors that are present in all kingdoms of life. The acronym, serpin, is derived from their function as potent serine proteases inhibitors. Early studies of serpins focused on their functions in haemostasis since modulating serine proteases activities are essential for coagulation. Additional research has revealed that serpins function in infection and inflammation, by modulating serine and cysteine proteases activities. The aim of this review is to summarize the accumulating findings and current understanding of the functions of serpins in host-pathogen interactions, serving as host defense proteins as well as pathogenic factors. We also discuss the potential crosstalk between host and pathogen serpins. We anticipate that future research will elucidate the therapeutic value of this novel target.

  20. Pathogenicity gene variations within the order Entomophthorales

    DEFF Research Database (Denmark)

    Grell, Morten Nedergaard; Jensen, Annette Bruun; Lange, Lene

    Fungi within the order Entomophthorales (subphylum Entomophthoromycotina) are obligate biotrophic pathogens of arthropods with a remarkable narrow host range. Infection takes place through the cuticle when conidia hit a susceptible host, facilitated by enzymatic and mechanical mechanisms. In the ...... pathogenicity genes within genera Entomophthora and Pandora, using fungal genomic DNA originating from field-collected, infected insect host species of dipteran (flies, mosquitoes) or hemipteran (aphid) origin.......Fungi within the order Entomophthorales (subphylum Entomophthoromycotina) are obligate biotrophic pathogens of arthropods with a remarkable narrow host range. Infection takes place through the cuticle when conidia hit a susceptible host, facilitated by enzymatic and mechanical mechanisms......, conidia are produced and discharged when humidity gets high—usually during night. In an earlier secretome study of field-collected grain aphids (Sitobion avenae) infected with entomophthoralean fungi, a number of pathogenesis-related, secreted enzymes were discovered (Fungal Genetics and Biology 2011, vol...

  1. Threats and opportunities of plant pathogenic bacteria.

    Science.gov (United States)

    Tarkowski, Petr; Vereecke, Danny

    2014-01-01

    Plant pathogenic bacteria can have devastating effects on plant productivity and yield. Nevertheless, because these often soil-dwelling bacteria have evolved to interact with eukaryotes, they generally exhibit a strong adaptivity, a versatile metabolism, and ingenious mechanisms tailored to modify the development of their hosts. Consequently, besides being a threat for agricultural practices, phytopathogens may also represent opportunities for plant production or be useful for specific biotechnological applications. Here, we illustrate this idea by reviewing the pathogenic strategies and the (potential) uses of five very different (hemi)biotrophic plant pathogenic bacteria: Agrobacterium tumefaciens, A. rhizogenes, Rhodococcus fascians, scab-inducing Streptomyces spp., and Pseudomonas syringae. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. Histone Acetylation in Fungal Pathogens of Plants

    Directory of Open Access Journals (Sweden)

    Junhyun Jeon

    2014-03-01

    Full Text Available Acetylation of histone lysine residues occurs in different organisms ranging from yeast to plants and mammals for the regulation of diverse cellular processes. With the identification of enzymes that create or reverse this modification, our understanding on histone acetylation has expanded at an amazing pace during the last two decades. In fungal pathogens of plants, however, the importance of such modification has only just begun to be appreciated in the recent years and there is a dearth of information on how histone acetylation is implicated in fungal pathogenesis. This review covers the current status of research related to histone acetylation in plant pathogenic fungi and considers relevant findings in the interaction between fungal pathogens and host plants. We first describe the families of histone acetyltransferases and deacetylases. Then we provide the cases where histone acetylation was investigated in the context of fungal pathogenesis. Finally, future directions and perspectives in epigenetics of fungal pathogenesis are discussed.

  3. Expression Study of Banana Pathogenic Resistance Genes

    Directory of Open Access Journals (Sweden)

    Fenny M. Dwivany

    2016-10-01

    Full Text Available Banana is one of the world's most important trade commodities. However, infection of banana pathogenic fungi (Fusarium oxysporum race 4 is one of the major causes of decreasing production in Indonesia. Genetic engineering has become an alternative way to control this problem by isolating genes that involved in plant defense mechanism against pathogens. Two of the important genes are API5 and ChiI1, each gene encodes apoptosis inhibitory protein and chitinase enzymes. The purpose of this study was to study the expression of API5 and ChiI1 genes as candidate pathogenic resistance genes. The amplified fragments were then cloned, sequenced, and confirmed with in silico studies. Based on sequence analysis, it is showed that partial API5 gene has putative transactivation domain and ChiI1 has 9 chitinase family GH19 protein motifs. Data obtained from this study will contribute in banana genetic improvement.

  4. Photoinactivation of major bacterial pathogens in aquaculture

    Directory of Open Access Journals (Sweden)

    Heyong Jin Roh

    2016-08-01

    Full Text Available Abstract Background Significant increases in the bacterial resistance to various antibiotics have been found in fish farms. Non-antibiotic therapies for infectious diseases in aquaculture are needed. In recent years, light-emitting diode technology has been applied to the inactivation of pathogens, especially those affecting humans. The purpose of this study was to assess the effect of blue light (wavelengths 405 and 465 nm on seven major bacterial pathogens that affect fish and shellfish important in aquaculture. Results We successfully demonstrate inactivation activity of a 405/465-nm LED on selected bacterial pathogens. Although some bacteria were not fully inactivated by the 465-nm light, the 405-nm light had a bactericidal effect against all seven pathogens, indicating that blue light can be effective without the addition of a photosensitizer. Photobacterium damselae, Vibrio anguillarum, and Edwardsiella tarda were the most susceptible to the 405-nm light (36.1, 41.2, and 68.4 J cm−2, respectively, produced one log reduction in the bacterial populations, whereas Streptococcus parauberis was the least susceptible (153.8 J cm−2 per one log reduction. In general, optical density (OD values indicated that higher bacterial densities were associated with lower inactivating efficacy, with the exception of P. damselae and Vibrio harveyi. In conclusion, growth of the bacterial fish and shellfish pathogens evaluated in this study was inactivated by exposure to either the 405- or 465-nm light. In addition, inactivation was dependent on exposure time. Conclusions This study presents that blue LED has potentially alternative therapy for treating fish and shellfish bacterial pathogens. It has great advantages in aspect of eco-friendly treating methods differed from antimicrobial methods.

  5. Differentiation between a pathogenic and a non-pathogenic form of Gyrodactylus salaris using PCR-RFLP

    DEFF Research Database (Denmark)

    Kania, Per Walther; Jørgensen, Thomas Rohde; Buchmann, Kurt

    2007-01-01

    A new method based on PCR-RFLP is presented. It is able to differentiate between the Danish non-pathogenic form of Gyrodactylus salaris and the Norwegian pathogenic form.......A new method based on PCR-RFLP is presented. It is able to differentiate between the Danish non-pathogenic form of Gyrodactylus salaris and the Norwegian pathogenic form....

  6. Molecular techniques for characterisation of pathogens

    DEFF Research Database (Denmark)

    Kampmann, Marie-Louise

    Pathogens have always had a major interest to humans due to their central role in sickness and death. Influenza A annually kills at least 250,000 humans, and has been the cause of millions of further deaths during pandemic years in the past. Plague (Yersinia pestis) has been the cause of the Black...... capture for the detection of Y. pestis in samples from the Justinian plague (600 AD) as an attempt to detect this pathogen as a cause of death in the victims....

  7. Whole-genome sequencing of veterinary pathogens

    DEFF Research Database (Denmark)

    Ronco, Troels

    -electrophoresis and single-locus sequencing has been widely used to characterize such types of veterinary pathogens. However, DNA sequencing techniques have become fast and cost effective in recent years and whole-genome sequencing data provide a much higher discriminative power and reproducibility than any...... genetic background. This indicates that dairy cows can be natural carriers of S. aureus subtypes that in certain cases lead to CM. A group of isolates that mostly belonged to ST151 carried three pathogenicity islands that were primarily found in this group. The prevalence of resistance genes was generally...

  8. The Tick Microbiome: Why Non-pathogenic Microorganisms Matter in Tick Biology and Pathogen Transmission

    Directory of Open Access Journals (Sweden)

    Sarah I. Bonnet

    2017-06-01

    Full Text Available Ticks are among the most important vectors of pathogens affecting humans and other animals worldwide. They do not only carry pathogens however, as a diverse group of commensal and symbiotic microorganisms are also present in ticks. Unlike pathogens, their biology and their effect on ticks remain largely unexplored, and are in fact often neglected. Nonetheless, they can confer multiple detrimental, neutral, or beneficial effects to their tick hosts, and can play various roles in fitness, nutritional adaptation, development, reproduction, defense against environmental stress, and immunity. Non-pathogenic microorganisms may also play a role in driving transmission of tick-borne pathogens (TBP, with many potential implications for both human and animal health. In addition, the genetic proximity of some pathogens to mutualistic symbionts hosted by ticks is evident when studying phylogenies of several bacterial genera. The best examples are found within members of the Rickettsia, Francisella, and Coxiella genera: while in medical and veterinary research these bacteria are traditionally recognized as highly virulent vertebrate pathogens, it is now clear to evolutionary ecologists that many (if not most Coxiella, Francisella, and Rickettsia bacteria are actually non-pathogenic microorganisms exhibiting alternative lifestyles as mutualistic ticks symbionts. Consequently, ticks represent a compelling yet challenging system in which to study microbiomes and microbial interactions, and to investigate the composition, functional, and ecological implications of bacterial communities. Ultimately, deciphering the relationships between tick microorganisms as well as tick symbiont interactions will garner invaluable information, which may aid in the future development of arthropod pest and vector-borne pathogen transmission control strategies.

  9. The Role of Pathogenic Autoantibodies in Autoimmunity

    Directory of Open Access Journals (Sweden)

    Merrill J. Rowley

    2015-11-01

    Full Text Available The serological presence of autoantibodies is diagnostic of autoimmunity, and these autoantibodies may be present for many years before the presentation of autoimmune disease (AID. Although a pathogenic role has been demonstrated for various autoantibodies reactive with cell surface and extracellular autoantigens, studies using monoclonal antibodies (mAb show not all antibodies in the polyclonal response are pathogenic. Differences depend on Fab-mediated diversity in epitope specificity, Fc-mediated effects based on immunoglobulin (Ig class and subclass, activation of complement, and the milieu in which the reaction occurs. These autoantibodies often occur in organ-specific AID and this review illustrates their pathogenic and highly specific effects. The role of autoantibodies associated with intracellular antigens is less clear. In vitro they may inhibit or adversely affect well-defined intracellular biochemical pathways, yet, in vivo they are separated from their autoantigens by multiple cellular barriers. Recent evidence that Ig can traverse cell membranes, interact with intracellular proteins, and induce apoptosis has provided new evidence for a pathogenic role for such autoantibodies. An understanding of how autoantibodies behave in the polyclonal response and their role in pathogenesis of AID may help identify populations of culprit B-cells and selection of treatments that suppress or eliminate them.

  10. Host-pathogen interactions in typhoid fever

    NARCIS (Netherlands)

    de Jong, H.K.

    2015-01-01

    This thesis focuses on host-pathogen interactions in Salmonella Typhi and Burkholderia pseudomallei infections and explores the interplay between these bacteria and the innate immune system. Typhoid fever is one of the most common causes of bacterial infection in low-income countries. With adequate

  11. Current situation on highly pathogenic avian influenza

    Science.gov (United States)

    Avian influenza is one of the most important diseases affecting the poultry industry worldwide. Avian influenza viruses can cause a range of clinical disease in poultry. Viruses that cause severe disease and mortality are referred to as highly pathogenic avian influenza (HPAI) viruses. The Asian ...

  12. RNAi suppressors encoded by pathogenic human viruses

    NARCIS (Netherlands)

    de Vries, Walter; Berkhout, Ben

    2008-01-01

    RNA silencing or RNAi interference (RNAi) serves as an innate antiviral mechanism in plants, fungi and animals. Human viruses, like plant viruses, encode suppressor proteins or RNAs that block or modulate the RNAi pathway. This review summarizes the mechanisms by which pathogenic human viruses

  13. Low-Incidence, High-Consequence Pathogens

    Centers for Disease Control (CDC) Podcasts

    2014-02-21

    Dr. Stephan Monroe, a deputy director at CDC, discusses the impact of low-incidence, high-consequence pathogens globally.  Created: 2/21/2014 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 2/26/2014.

  14. Rapid methods: the detection of foodborne pathogens

    NARCIS (Netherlands)

    Beumer, R.R.; Hazeleger, W.C.

    2009-01-01

    Although bacteria are the first type of microorganisms that come to mind when discussing microbial food safety, they are by no means the only pathogenic foodborne microorganisms. Mycotoxin producing moulds, human enteric viruses, protozoan parasites and marine biotoxins are also of importance.

  15. Quantitative multiplex detection of pathogen biomarkers

    Energy Technology Data Exchange (ETDEWEB)

    Mukundan, Harshini; Xie, Hongzhi; Swanson, Basil I.; Martinez, Jennifer; Grace, Wynne K.

    2016-02-09

    The present invention addresses the simultaneous detection and quantitative measurement of multiple biomolecules, e.g., pathogen biomarkers through either a sandwich assay approach or a lipid insertion approach. The invention can further employ a multichannel, structure with multi-sensor elements per channel.

  16. Pathogen Pressure Puts Immune Defense into Perspective

    NARCIS (Netherlands)

    Horrocks, Nicholas P. C.; Matson, Kevin D.; Tieleman, B. Irene

    2011-01-01

    The extent to which organisms can protect themselves from disease depends on both the immune defenses they maintain and the pathogens they face. At the same time, immune systems are shaped by the antigens they encounter, both over ecological and evolutionary time. Ecological immunologists often

  17. Control of indigenous pathogenic bacteria in seafood

    DEFF Research Database (Denmark)

    Huss, Hans Henrik

    1997-01-01

    The pathogenic bacteria indigenous to the aquatic and general environment are listed. Their distribution in nature, prevalence in seafood and the possibilities for growth of these organisms in various types of products are outlined These data, combined with what is known regarding the epidemiology...

  18. EPCOT, NASA and plant pathogens in space.

    Science.gov (United States)

    White, R

    1996-01-01

    Cooperative work between NASA and Walt Disney World's EPCOT Land Pavilion is described. Joint efforts include research about allelopathy in multi-species plant cropping in CELSS, LEDs as light sources in hydroponic systems, and the growth of plant pathogens in space.

  19. Quantitative multiplex detection of pathogen biomarkers

    Science.gov (United States)

    Mukundan, Harshini; Xie, Hongzhi; Swanson, Basil I; Martinez, Jennifer; Grace, Wynne K

    2014-10-14

    The present invention addresses the simultaneous detection and quantitative measurement of multiple biomolecules, e.g., pathogen biomarkers through either a sandwich assay approach or a lipid insertion approach. The invention can further employ a multichannel, structure with multi-sensor elements per channel.

  20. Cultural, morphological, pathogenic and molecular characterization ...

    African Journals Online (AJOL)

    Alternaria blotch (Alternaria mali) causes severe foliar damage to apple trees in Kashmir. Twenty one (21) isolates of A. mali were collected from different locations and characterized for cultural, morphological, pathogenic and molecular variations. A. mali colonies varied in their cultural behaviour ranging from velvety to ...

  1. Paleogene radiation of a plant pathogenic mushroom.

    Directory of Open Access Journals (Sweden)

    Martin P A Coetzee

    Full Text Available The global movement and speciation of fungal plant pathogens is important, especially because of the economic losses they cause and the ease with which they are able to spread across large areas. Understanding the biogeography and origin of these plant pathogens can provide insights regarding their dispersal and current day distribution. We tested the hypothesis of a Gondwanan origin of the plant pathogenic mushroom genus Armillaria and the currently accepted premise that vicariance accounts for the extant distribution of the species.The phylogeny of a selection of Armillaria species was reconstructed based on Maximum Parsimony (MP, Maximum Likelihood (ML and Bayesian Inference (BI. A timeline was then placed on the divergence of lineages using a Bayesian relaxed molecular clock approach.Phylogenetic analyses of sequenced data for three combined nuclear regions provided strong support for three major geographically defined clades: Holarctic, South American-Australasian and African. Molecular dating placed the initial radiation of the genus at 54 million years ago within the Early Paleogene, postdating the tectonic break-up of Gondwana.The distribution of extant Armillaria species is the result of ancient long-distance dispersal rather than vicariance due to continental drift. As these finding are contrary to most prior vicariance hypotheses for fungi, our results highlight the important role of long-distance dispersal in the radiation of fungal pathogens from the Southern Hemisphere.

  2. Novel Micro-organisms controlling plant pathogens

    NARCIS (Netherlands)

    Köhl, J.

    2009-01-01

    The invention relates to control of pathogen caused diseases on leaves, fruits and ears in plants, such as apple scab (Venturia inaequalis by treatment of plant with an isolate of Cladosporium cladosporioides. The treatment is effective in both prevention and treatment of the fungal infection

  3. Novel Micro-organisms controlling plant pathogens

    NARCIS (Netherlands)

    Köhl, J.

    2010-01-01

    The invention relates to control of pathogen caused diseases on leaves, fruits and ears in plants, such as apple scab (Venturia inaequalis by treatment of plant with an isolate of Cladosporium cladosporioides. The treatment is effective in both prevention and treatment of the fungal infection

  4. PATHOGENIC POTENTIALS OF ESCHERICHIA COLI ISOLATED ...

    African Journals Online (AJOL)

    Electrolyte and haematological parameters in rabbits infected with pathogenic isolates of Escherichia coli from rural water supplies in Rivers State, Nigeria, where monitored. Rabbits were orally infected with suspension containing 3x107 cfu /ml of Escherichia coli to induce diarrhoea, and the electrolyte (sodium, potassium ...

  5. Microbial minimalism: genome reduction in bacterial pathogens.

    Science.gov (United States)

    Moran, Nancy A

    2002-03-08

    When bacterial lineages make the transition from free-living or facultatively parasitic life cycles to permanent associations with hosts, they undergo a major loss of genes and DNA. Complete genome sequences are providing an understanding of how extreme genome reduction affects evolutionary directions and metabolic capabilities of obligate pathogens and symbionts.

  6. Plastic Transcriptomes Stabilize Immunity to Pathogen Diversity

    DEFF Research Database (Denmark)

    Zhang, Wei; Corwin, Jason A; Copeland, Daniel

    2017-01-01

    To respond to pathogen attack, selection and associated evolution has led to the creation of plant immune system that are a highly effective and inducible defense system. Central to this system are the plant defense hormones jasmonic acid (JA) and salicylic acid (SA) and crosstalk between the two...

  7. Host-pathogen interactions during apoptosis

    Indian Academy of Sciences (India)

    Unknown

    349. Keywords. Antioxidant; baculovirus; host-pathogen; eIF2α-kinase; P35; PKR .... conferring a selective advantage to the virus, the capacity to prevent apoptosis is ..... totic extracts were found to cleave purified PKR in vitro. These findings ...

  8. Plastic transcriptomes stabilize immunity to pathogen diversity

    DEFF Research Database (Denmark)

    Zhang, Wei; Corwin, Jason A.; Copeland, Daniel

    2017-01-01

    To respond to pathogen attack, selection and associated evolution has led to the creation of plant immune system that are a highly effective and inducible defense system. Central to this system are the plant defense hormones jasmonic acid (JA) and salicylic acid (SA) and crosstalk between the two...

  9. Pathogenic human viruses in coastal waters

    Science.gov (United States)

    Griffin, Dale W.; Donaldson, Kim A.; Paul, J.H.; Rose, Joan B.

    2003-01-01

    This review addresses both historical and recent investigations into viral contamination of marine waters. With the relatively recent emergence of molecular biology-based assays, a number of investigations have shown that pathogenic viruses are prevalent in marine waters being impacted by sewage. Research has shown that this group of fecal-oral viral pathogens (enteroviruses, hepatitis A viruses, Norwalk viruses, reoviruses, adenoviruses, rotaviruses, etc.) can cause a broad range of asymptomatic to severe gastrointestinal, respiratory, and eye, nose, ear, and skin infections in people exposed through recreational use of the water. The viruses and the nucleic acid signature survive for an extended period in the marine environment. One of the primary concerns of public health officials is the relationship between the presence of pathogens and the recreational risk to human health in polluted marine environments. While a number of studies have attempted to address this issue, the relationship is still poorly understood. A contributing factor to our lack of progress in the field has been the lack of sensitive methods to detect the broad range of both bacterial and viral pathogens. The application of new and advanced molecular methods will continue to contribute to our current state of knowledge in this emerging and

  10. Campylobacter jejuni & Inflammation : Grilling the pathogen

    NARCIS (Netherlands)

    Bouwman, L.I.

    2016-01-01

    Campylobacter jejuni is the most common cause of bacterial foodborne disease. Yet, little is known about how this pathogen causes intestinal inflammation. The clinical pathology during human infection points to invasive bacterial behavior accompanied by the induction of potent pro-inflammatory

  11. The making of a new pathogen

    DEFF Research Database (Denmark)

    Stukenbrock, Eva; Bataillon, Thomas; Dutheil, Julien

    2011-01-01

    that gene-rich regions or regions with low recombination experience stronger effects of natural selection on neutral diversity. Emergence of a new agricultural host selected a highly specialized and fast-evolving pathogen with unique evolutionary patterns compared with its wild relatives. The strong impact...

  12. Home Air Purifiers Eradicate Harmful Pathogens

    Science.gov (United States)

    2014-01-01

    Marshall Space Flight Center funded the University of Madison-Wisconsin to develop ethylene scrubbers to keep produce fresh in space. Akida Holdings of Jacksonville, Florida, licensed the technology and developed Airocide, an air purifier that can kill airborne pathogens. Previously designed for industrial spaces, there is now a specially designed unit for home use.

  13. Carp erythrodermatitis : host defense-pathogen interaction

    NARCIS (Netherlands)

    Pourreau, C.N.

    1990-01-01

    The outcome of a bacterial infection depends on the interaction between pathogen and host. The ability of the microbe to survive in the host depends on its invasive potential (i.e. spreading and multiplication), and its ability to obtain essential nutrients and to resist the

  14. Antibiotic susceptibility profiles of oral pathogens

    NARCIS (Netherlands)

    Veloo, A. C. M.; Seme, K.; Raangs, Gerwin; Rurenga, P.; Singadji, Z.; Wekema - Mulder, G.; van Winkelhoff, A. J.

    2012-01-01

    Periodontitis is a bacterial disease that can be treated with systemic antibiotics. The aim of this study was to establish the antibiotic susceptibility profiles of five periodontal pathogens to six commonly used antibiotics in periodontics. A total of 247 periodontal bacterial isolates were tested

  15. Morphological, cultural, pathogenic and molecular variability ...

    African Journals Online (AJOL)

    Alternaria blight (Alternaria brassicae) causes severe foliar damage to Indian mustard in Uttarakhand. Ten (10) isolates of A. brassicae were collected from different hosts and characterized for cultural, morphological, pathogenic and molecular variations. A. brassicae colonies varied in their cultural behaviour ranging from ...

  16. Ewingella Americana: An Emerging True Pathogen

    Directory of Open Access Journals (Sweden)

    Syed Hassan

    2012-01-01

    Full Text Available Infections caused by Ewingella americana have been rarely reported in the literature. Most of the cases that have been reported were among the immunocompromised patients. We report a case of E. americana causing osteomyelitis and septic arthritis of the shoulder joint in a previous intravenous drug abuser. The causative pathogen was identified by synovial fluid analysis and culture.

  17. Arginase activity in pathogenic and non-pathogenic species of Leishmania parasites.

    Science.gov (United States)

    Badirzadeh, Alireza; Taheri, Tahereh; Taslimi, Yasaman; Abdossamadi, Zahra; Heidari-Kharaji, Maryam; Gholami, Elham; Sedaghat, Baharehsadat; Niyyati, Maryam; Rafati, Sima

    2017-07-01

    Proliferation of Leishmania (L.) parasites depends on polyamine availability, which can be generated by the L-arginine catabolism and the enzymatic activity of arginase (ARG) of the parasites and of the mammalian hosts. In the present study, we characterized and compared the arginase (arg) genes from pathogenic L. major and L. tropica and from non-pathogenic L. tarentolae. We quantified the level of the ARG activity in promastigotes and macrophages infected with pathogenic L. major and L. tropica and non-pathogenic L. tarentolae amastigotes. The ARG's amino acid sequences of the pathogenic and non-pathogenic Leishmania demonstrated virtually 98.6% and 88% identities with the reference L. major Friedlin ARG. Higher ARG activity was observed in all pathogenic promastigotes as compared to non-pathogenic L. tarentolae. In vitro infection of human macrophage cell line (THP1) with pathogenic and non-pathogenic Leishmania spp. resulted in increased ARG activities in the infected macrophages. The ARG activities present in vivo were assessed in susceptible BALB/c and resistant C57BL/6 mice infected with L. major, L. tropica and L. tarentolae. We demonstrated that during the development of the infection, ARG is induced in both strains of mice infected with pathogenic Leishmania. However, in L. major infected BALB/c mice, the induction of ARG and parasite load increased simultaneously according to the time course of infection, whereas in C57BL/6 mice, the enzyme is upregulated solely during the period of footpad swelling. In L. tropica infected mice, the footpads' swellings were slow to develop and demonstrated minimal cutaneous pathology and ARG activity. In contrast, ARG activity was undetectable in mice inoculated with the non-pathogenic L. tarentolae. Our data suggest that infection by Leishmania parasites can increase ARG activity of the host and provides essential polyamines for parasite salvage and its replication. Moreover, the ARG of Leishmania is vital for parasite

  18. The sunflower downy mildew pathogen Plasmopara halstedii.

    Science.gov (United States)

    Gascuel, Quentin; Martinez, Yves; Boniface, Marie-Claude; Vear, Felicity; Pichon, Magalie; Godiard, Laurence

    2015-02-01

    Downy mildew of sunflower is caused by Plasmopara halstedii (Farlow) Berlese & de Toni. Plasmopara halstedii is an obligate biotrophic oomycete pathogen that attacks annual Helianthus species and cultivated sunflower, Helianthus annuus. Depending on the sunflower developmental stage at which infection occurs, the characteristic symptoms range from young seedling death, plant dwarfing, leaf bleaching and sporulation to the production of infertile flowers. Downy mildew attacks can have a great economic impact on sunflower crops, and several Pl resistance genes are present in cultivars to protect them against the disease. Nevertheless, some of these resistances have been overcome by the occurrence of novel isolates of the pathogen showing increased virulence. A better characterization of P. halstedii infection and dissemination mechanisms, and the identification of the molecular basis of the interaction with sunflower, is a prerequisite to efficiently fight this pathogen. This review summarizes what is currently known about P. halstedii, provides new insights into its infection cycle on resistant and susceptible sunflower lines using scanning electron and light microscopy imaging, and sheds light on the pathogenicity factors of P. halstedii obtained from recent molecular data. Kingdom Stramenopila; Phylum Oomycota; Class Oomycetes; Order Peronosporales; Family Peronosporaceae; Genus Plasmopara; Species Plasmopara halstedii. Sunflower seedling damping off, dwarfing of the plant, bleaching of leaves, starting from veins, and visible white sporulation, initially on the lower side of cotyledons and leaves. Plasmopara halstedii infection may severely impact sunflower seed yield. In spring, germination of overwintered sexual oospores leads to sunflower root infection. Intercellular hyphae are responsible for systemic plant colonization and the induction of disease symptoms. Under humid and fresh conditions, dissemination structures are produced by the pathogen on all

  19. Overexpression of Differentially Expressed Genes Identified in Non-pathogenic and Pathogenic Entamoeba histolytica Clones Allow Identification of New Pathogenicity Factors Involved in Amoebic Liver Abscess Formation.

    Directory of Open Access Journals (Sweden)

    Martin Meyer

    2016-08-01

    Full Text Available We here compared pathogenic (p and non-pathogenic (np isolates of Entamoeba histolytica to identify molecules involved in the ability of this parasite to induce amoebic liver abscess (ALA-like lesions in two rodent models for the disease. We performed a comprehensive analysis of 12 clones (A1-A12 derived from a non-pathogenic isolate HM-1:IMSS-A and 12 clones (B1-B12 derived from a pathogenic isolate HM-1:IMSS-B. "Non-pathogenicity" included the induction of small and quickly resolved lesions while "pathogenicity" comprised larger abscess development that overstayed day 7 post infection. All A-clones were designated as non-pathogenic, whereas 4 out of 12 B-clones lost their ability to induce ALAs in gerbils. No correlation between ALA formation and cysteine peptidase (CP activity, haemolytic activity, erythrophagocytosis, motility or cytopathic activity was found. To identify the molecular framework underlying different pathogenic phenotypes, three clones were selected for in-depth transcriptome analyses. Comparison of a non-pathogenic clone A1np with pathogenic clone B2p revealed 76 differentially expressed genes, whereas comparison of a non-pathogenic clone B8np with B2p revealed only 19 differentially expressed genes. Only six genes were found to be similarly regulated in the two non-pathogenic clones A1np and B8np in comparison with the pathogenic clone B2p. Based on these analyses, we chose 20 candidate genes and evaluated their roles in ALA formation using the respective gene-overexpressing transfectants. We conclude that different mechanisms lead to loss of pathogenicity. In total, we identified eight proteins, comprising a metallopeptidase, C2 domain proteins, alcohol dehydrogenases and hypothetical proteins, that affect the pathogenicity of E. histolytica.

  20. Overexpression of Differentially Expressed Genes Identified in Non-pathogenic and Pathogenic Entamoeba histolytica Clones Allow Identification of New Pathogenicity Factors Involved in Amoebic Liver Abscess Formation.

    Science.gov (United States)

    Meyer, Martin; Fehling, Helena; Matthiesen, Jenny; Lorenzen, Stephan; Schuldt, Kathrin; Bernin, Hannah; Zaruba, Mareen; Lender, Corinna; Ernst, Thomas; Ittrich, Harald; Roeder, Thomas; Tannich, Egbert; Lotter, Hannelore; Bruchhaus, Iris

    2016-08-01

    We here compared pathogenic (p) and non-pathogenic (np) isolates of Entamoeba histolytica to identify molecules involved in the ability of this parasite to induce amoebic liver abscess (ALA)-like lesions in two rodent models for the disease. We performed a comprehensive analysis of 12 clones (A1-A12) derived from a non-pathogenic isolate HM-1:IMSS-A and 12 clones (B1-B12) derived from a pathogenic isolate HM-1:IMSS-B. "Non-pathogenicity" included the induction of small and quickly resolved lesions while "pathogenicity" comprised larger abscess development that overstayed day 7 post infection. All A-clones were designated as non-pathogenic, whereas 4 out of 12 B-clones lost their ability to induce ALAs in gerbils. No correlation between ALA formation and cysteine peptidase (CP) activity, haemolytic activity, erythrophagocytosis, motility or cytopathic activity was found. To identify the molecular framework underlying different pathogenic phenotypes, three clones were selected for in-depth transcriptome analyses. Comparison of a non-pathogenic clone A1np with pathogenic clone B2p revealed 76 differentially expressed genes, whereas comparison of a non-pathogenic clone B8np with B2p revealed only 19 differentially expressed genes. Only six genes were found to be similarly regulated in the two non-pathogenic clones A1np and B8np in comparison with the pathogenic clone B2p. Based on these analyses, we chose 20 candidate genes and evaluated their roles in ALA formation using the respective gene-overexpressing transfectants. We conclude that different mechanisms lead to loss of pathogenicity. In total, we identified eight proteins, comprising a metallopeptidase, C2 domain proteins, alcohol dehydrogenases and hypothetical proteins, that affect the pathogenicity of E. histolytica.

  1. Bacteriophages for detection of bacterial pathogens

    International Nuclear Information System (INIS)

    Kutateladze, M.

    2009-01-01

    The G. Eliava Institute of Bacteriophages, Microbiology and Virology (Tbilisi, Georgia) is one of the most famous institutions focused on bacteriophage research for the elaboration of appropriate phage methodologies for human and animal protection. The main direction of the institute is the study and production of bacteriophages against intestinal disorders (dysentery, typhoid, intesti) and purulent-septic infections (staphylococcus, streptococcus, pyophage, etc.). These preparations were successfully introduced during the Soviet era, and for decades were used throughout the former Soviet Union and in other Socialist countries for the treatment, prophylaxis, and diagnosis of various infectious diseases, including those caused by antibiotic-resistant bacterial strains. Bacteriophages were widely used for identifying and detecting infections caused by the most dangerous pathogens and causative agents of epidemiological outbreaks. The specific topic of this presentation is the phage typing of bacterial species, which can be an important method for epidemiological diagnostics. Together with different genetic methodologies - such as PCR-based methods, PFGE, plasmid fingerprinting, and ribosomal typing - phage typing is one method for identifying bacterial pathogens. The method has a high percentage of determination of phage types, high specificity of reaction, and is easy for interpretation and use by health workers. Phage typing was applied for inter-species differentiation of different species of Salmonella, S. typhi, Brucella spp, Staphylococcus aureus, E. col,i Clostridium deficile, Vibrio cholerae, Yersinia pestis, Yersinia enterocolitica, Lysteria monocytogenes, Clostridium perfringens, Clostridium tetani, plant pathogens, and other bacterial pathogens. In addition to addressing the utility and efficacy of phage typing, the paper will discuss the isolation and selection of diagnostic typing phages for interspecies differentiation of pathogens that is necessary

  2. Recent developments in pathogen detection arrays: implications for fungal plant pathogens and use in practica

    NARCIS (Netherlands)

    Lievens, B.; Thomma, B.P.H.J.

    2005-01-01

    The failure to adequately identify plant pathogens from culture-based morphological techniques has led to the development of culture-independent molecular approaches. Increasingly, diagnostic laboratories are pursuing fast routine methods that provide reliable identification, sensitive detection,

  3. A fungal pathogen of amphibians, Batrachochytrium dendrobatidis, attenuates in pathogenicity with in vitro passages.

    Science.gov (United States)

    Langhammer, Penny F; Lips, Karen R; Burrowes, Patricia A; Tunstall, Tate; Palmer, Crystal M; Collins, James P

    2013-01-01

    Laboratory investigations into the amphibian chytrid fungus, Batrachochytrium dendrobatidis (Bd), have accelerated recently, given the pathogen's role in causing the global decline and extinction of amphibians. Studies in which host animals were exposed to Bd have largely assumed that lab-maintained pathogen cultures retained the infective and pathogenic properties of wild isolates. Attenuated pathogenicity is common in artificially maintained cultures of other pathogenic fungi, but to date, it is unknown whether, and to what degree, Bd might change in culture. We compared zoospore production over time in two samples of a single Bd isolate having different passage histories: one maintained in artificial media for more than six years (JEL427-P39), and one recently thawed from cryopreserved stock (JEL427-P9). In a common garden experiment, we then exposed two different amphibian species, Eleutherodactylus coqui and Atelopus zeteki, to both cultures to test whether Bd attenuates in pathogenicity with in vitro passages. The culture with the shorter passage history, JEL427-P9, had significantly greater zoospore densities over time compared to JEL427-P39. This difference in zoospore production was associated with a difference in pathogenicity for a susceptible amphibian species, indicating that fecundity may be an important virulence factor for Bd. In the 130-day experiment, Atelopus zeteki frogs exposed to the JEL427-P9 culture experienced higher average infection intensity and 100% mortality, compared with 60% mortality for frogs exposed to JEL427-P39. This effect was not observed with Eleutherodactylus coqui, which was able to clear infection. We hypothesize that the differences in phenotypic performance observed with Atelopus zeteki are rooted in changes of the Bd genome. Future investigations enabled by this study will focus on the underlying mechanisms of Bd pathogenicity.

  4. A fungal pathogen of amphibians, Batrachochytrium dendrobatidis, attenuates in pathogenicity with in vitro passages.

    Directory of Open Access Journals (Sweden)

    Penny F Langhammer

    Full Text Available Laboratory investigations into the amphibian chytrid fungus, Batrachochytrium dendrobatidis (Bd, have accelerated recently, given the pathogen's role in causing the global decline and extinction of amphibians. Studies in which host animals were exposed to Bd have largely assumed that lab-maintained pathogen cultures retained the infective and pathogenic properties of wild isolates. Attenuated pathogenicity is common in artificially maintained cultures of other pathogenic fungi, but to date, it is unknown whether, and to what degree, Bd might change in culture. We compared zoospore production over time in two samples of a single Bd isolate having different passage histories: one maintained in artificial media for more than six years (JEL427-P39, and one recently thawed from cryopreserved stock (JEL427-P9. In a common garden experiment, we then exposed two different amphibian species, Eleutherodactylus coqui and Atelopus zeteki, to both cultures to test whether Bd attenuates in pathogenicity with in vitro passages. The culture with the shorter passage history, JEL427-P9, had significantly greater zoospore densities over time compared to JEL427-P39. This difference in zoospore production was associated with a difference in pathogenicity for a susceptible amphibian species, indicating that fecundity may be an important virulence factor for Bd. In the 130-day experiment, Atelopus zeteki frogs exposed to the JEL427-P9 culture experienced higher average infection intensity and 100% mortality, compared with 60% mortality for frogs exposed to JEL427-P39. This effect was not observed with Eleutherodactylus coqui, which was able to clear infection. We hypothesize that the differences in phenotypic performance observed with Atelopus zeteki are rooted in changes of the Bd genome. Future investigations enabled by this study will focus on the underlying mechanisms of Bd pathogenicity.

  5. Lipids in host-pathogen interactions: pathogens exploit the complexity of the host cell lipidome.

    Science.gov (United States)

    van der Meer-Janssen, Ynske P M; van Galen, Josse; Batenburg, Joseph J; Helms, J Bernd

    2010-01-01

    Lipids were long believed to have a structural role in biomembranes and a role in energy storage utilizing cellular lipid droplets and plasma lipoproteins. Research over the last decades has identified an additional role of lipids in cellular signaling, membrane microdomain organization and dynamics, and membrane trafficking. These properties make lipids an attractive target for pathogens to modulate host cell processes in order to allow their survival and replication. In this review we will summarize the often ingenious strategies of pathogens to modify the lipid homeostasis of host cells, allowing them to divert cellular processes. To this end pathogens take full advantage of the complexity of the lipidome. The examples are categorized in generalized and emerging principles describing the involvement of lipids in host-pathogen interactions. Several pathogens are described that simultaneously induce multiple changes in the host cell signaling and trafficking mechanisms. Elucidation of these pathogen-induced changes may have important implications for drug development. The emergence of high-throughput lipidomic techniques will allow the description of changes of the host cell lipidome at the level of individual molecular lipid species and the identification of lipid biomarkers.

  6. Molecular Diagnostics for Soilborne Fungal Pathogens

    Directory of Open Access Journals (Sweden)

    E.J. Paplomatas

    2004-08-01

    Full Text Available Several classical approaches have been developed to detect and identify soil fungal inhabitants through the years. Selective media have been devised to exclude the large number of soil organisms and allow growth of target fungi. However the advent of molecular biology has offered a number of revolutionary insights into the detection and enumeration of soilborne fungal pathogens and also has started to provide information on the identification of unknown species from DNA sequences. This review paper focuses on the application of various molecular techniques in the detection, identification, characterization and quantification of soilborne fungal plant pathogens. This is based on information from the literature and is combined with personal research findings of the author.

  7. Bacteriophage interactions with marine pathogenic Vibrios

    DEFF Research Database (Denmark)

    Kalatzis, Panagiotis

    development and spreading of antibiotic resistant bacteria in the environment. Bacteriophage therapy, constitutes a potent alternative not only for treatment but also for prevention of vibriosis in aquaculture and the current thesis addresses the potential and challenges of using phages to control Vibrio...... pathogens. The combinatory administration of virulent bacteriophages φSt2 and φGrn1, isolated against Vibrio alginolyticus significantly reduced the Vibrio load in cultures of Artemia salina live prey, decreasing subsequently the risk of a vibriosis outbreak in the marine hatchery. During infection...... therapy applications. Lytic phage vB_VspP_pVa5 that has been isolated against the rapidly emerging pathogen V. splendidus is also a promising candidate for phage therapy application according to its gene content and in vitro performance against its host. The genetic features of vB_VspP_pVa5 provide also...

  8. Susceptibility of Postharvest Pathogens to Esential Oils

    Directory of Open Access Journals (Sweden)

    Božik M.

    2017-09-01

    Full Text Available Antimicrobial volatile substances from plants represent alternatives to synthetic pesticides and food preservatives. In this study, the compositions of some essential oils were determined by gas chromatography with mass spectrometry, and the inhibitory properties of the essential oils and their components against the bacterial postharvest pathogens Pectobacterium carotovorum subsp. carotovorum (CCM 1008, Pseudomonas syringae (CCM 7018, Xanthomonas campestris (CCM 22 were determined by the microdilution method. Essential oils from oregano, cinnamon, lemongrass, lavender, clove, rosemary, tea tree, eucalyptus, garlic, and ginger and their components cinnamaldehyde, eugenol, thymol, and carvacrol were used in the tests. The essential oil components exhibited strong antibacterial activity against all tested bacteria. The oregano and cinnamon essential oils were most effective. The rosemary, lavender, tea tree, eucalyptus, garlic, and ginger oils were not effective at the tested concentrations. In conclusion, certain essential oils, particularly their components, are highly effective and could be used for the control of postharvest bacterial pathogens.

  9. Actinobaculum schaalii: A truly emerging pathogen?

    Science.gov (United States)

    Prigent, G.; Perillaud, C.; Amara, M.; Coutard, A.; Blanc, C.; Pangon, B.

    2016-01-01

    Actinobaculum schaalii is a Gram-positive facultative anaerobe bacillus. It is a commensal organism of the genitourinary tract. Its morphology is nonspecific. Aerobic culture is tedious, and identification techniques have long been inadequate. Thus, A. schaalii has often been considered as a nonpathogen bacterium or a contaminant. Its pathogenicity is now well described in urinary tract infections, and infections in other sites have been reported. This pathogen is considered as an emerging one following the growing use of mass spectrometry identification. In this context, the aim of our study was to evaluate the number of isolations of A. schaalii before and after the introduction of mass spectrometry in our hospital and to study the clinical circumstances in which isolates were found. PMID:27014462

  10. OSHA Bloodborne Pathogens Standards Exposure Control Plan

    Science.gov (United States)

    Luhrs, Caro Elise; Teitelbaum, Rita

    1993-01-01

    The Hummer Associates Exposure Control Plan is designed to reduce significant occupational exposure to bloodborne pathogens and infectious materials for Hummer Associates health care personnel. Under universal precautions, all patients and all body fluids are considered potentially infectious for bloodborne pathogens. Medical personnel need not be at increased risk if universal precautions are correctly understood and followed. This program covers all employees who could reasonably anticipate contact with blood or other potentially infectious materials during the performance of their job responsibilities. Although HIV and hepatitis B are mentioned most often, this program applies to all bloodborne diseases. The two main components needed to implement this program are universal precautions and engineering/work practice controls. This program covers all employees who may have occupational exposure to blood or other potentially infectious materials. Other aspects of this program are discussed.

  11. Main Concerns of Pathogenic Microorganisms in Meat

    Science.gov (United States)

    Nørrung, Birgit; Andersen, Jens Kirk; Buncic, Sava

    Although various foods can serve as sources of foodborne illness, meat and meat products are important sources of human infections with a variety of foodborne pathogens, i.e. Salmonella spp., Campylobacter jejuni/coli, Yersinia enterocolitica, Verotoxigenic E. coli and, to some extent, Listeria monocytogenes. All these may be harboured in the gastrointestinal tract of food-producing animals. The most frequent chain of events leading to meat-borne illness involves food animals, which are healthy carriers of the pathogens that are subsequently transferred to humans through production, handling and consumption of meat and meat products. Occurrences of Salmonella spp., C. jejuni/coli, Y. enterocolitica and Verotoxigenic E. coli in fresh red meat vary relatively widely, although most often are between 1 and 10%, depending on a range of factors including the organism, geographical factors, farming and/or meat production practices.

  12. Plant pathology: monitoring a pathogen-targeted host protein.

    Science.gov (United States)

    Ellis, Jeff; Dodds, Peter

    2003-05-13

    A plant protein RIN4 is targeted and modified by bacterial pathogens as part of the disease process. At least two host resistance proteins monitor this pathogen interference and trigger the plant's defence responses.

  13. PHIDIAS- Pathogen Host Interaction Data Integration and Analysis

    Indian Academy of Sciences (India)

    PHIDIAS- Pathogen Host Interaction Data Integration and Analysis- allows searching of integrated genome sequences, conserved domains and gene expressions data related to pathogen host interactions in high priority agents for public health and security ...

  14. Isolation of antibiotic-resistant pathogenic and potentially ...

    African Journals Online (AJOL)

    2010-09-13

    Sep 13, 2010 ... The aim of the present study is to determine the pathogenic and potentially ... Keywords: pathogenic bacteria; antibiotic resistance; carpets; mosques; Tripoli; Libya .... During the process of praying, a Muslim is obliged to go.

  15. In vitro inhibition of pathogenic Verticillium dahliae, causal agent of ...

    African Journals Online (AJOL)

    SAM

    2014-08-13

    Aug 13, 2014 ... In addition, plant pathogens directly affected through antibiosis and ... Trichoderma strains for antagonistic activity on the fungal pathogen V. ... Five soil sub samples were taken from the area around the healthy potato roots ...

  16. Biocontrol interventions for inactivation of foodborne pathogens on produce

    Science.gov (United States)

    Post-harvest interventions for control of foodborne pathogens on minimally processed foods are crucial for food safety. Biocontrol interventions have the primary objective of developing novel antagonists in combinations with physical and chemical interventions to inactivate pathogenic microbes. Ther...

  17. Childhood urinary tract infection in Benin City: pathogens and ...

    African Journals Online (AJOL)

    Childhood urinary tract infection in Benin City: pathogens and antimicrobial ... of bacterial isolates implicated in urinary tract infection (UTI) amongst children was ... There is also an emerging resistance of common pathogens to azithromycin ...

  18. Swainsonine biosynthesis genes in diverse symbiotic and pathogenic fungi

    Science.gov (United States)

    Swainsonine, a cytotoxic fungal alkaloid and a potential cancer therapy drug, is produced by the insect pathogen and plant symbiont, Metarhizium robertsii, the clover pathogen Slafractonia leguminicola, locoweed symbionts belonging to Alternaria sect. Undifilum, and a recently discovered morning glo...

  19. Carp erythrodermatitis : host defense-pathogen interaction

    OpenAIRE

    Pourreau, C.N.

    1990-01-01

    The outcome of a bacterial infection depends on the interaction between pathogen and host. The ability of the microbe to survive in the host depends on its invasive potential (i.e. spreading and multiplication), and its ability to obtain essential nutrients and to resist the host's defense system. On the other hand, the host's resistance to a bacterial attack depends on its physiological state, the intensity of the bacterial attack and the efficacy of the defense system to ...

  20. Occurrence of antimicrobial resistance among bacterial pathogens

    OpenAIRE

    Hendriksen, Rene S.; Mevius, Dik J.; Schroeter, Andreas; Teale, Christopher; Jouy, Eric; Butaye, Patrick; Franco, Alessia; Utinane, Andra; Amado, Alice; Moreno, Miguel; Greko, Christina; Stärk, Katharina D.C.; Berghold, Christian; Myllyniemi, Anna-Liisa; Hoszowski, Andrzej

    2008-01-01

    Background: The project "Antibiotic resistance in bacteria of animal origin – II" (ARBAO-II) was funded by the European Union (FAIR5-QLK2-2002-01146) for the period 2003–05. The aim of this project was to establish a program for the continuous monitoring of antimicrobial susceptibility of pathogenic and indicator bacteria from food animals using validated and harmonised methodologies. In this report the first data on the occurrence of antimicrobial resistance among bacteria cau...

  1. Pathogenic and opportunistic microorganisms in caves

    Directory of Open Access Journals (Sweden)

    Sanchez-Moral Sergio

    2010-01-01

    Full Text Available With today’s leisure tourism, the frequency of visits to many caves makes it necessary to know about possible potentially pathogenic microorganisms in caves, determine their reservoirs, and inform the public about the consequences of such visits. Our data reveal that caves could be a potential danger to visitors because of the presence of opportunistic microorganisms, whose existence and possible development in humans is currently unknown.

  2. Pathogen Inactivated Plasma Concentrated: Preparation and Uses

    Science.gov (United States)

    2004-09-01

    of decontamination, porcine parvovirus (PPV) was selected as a model virus; B19 is the form that infects humans. PPV is an interesting pathogen...ultrasound to cold plasma. The ultrasound generates pure ice crystals, which are then removed to leave concentrated plasma. Testing: Porcine parvovirus ...energy to “burn” any proteins that they encounter. Furthermore, as they react, they also produce multiple other reactive oxygen species (ROS) that are

  3. Swiss Army Pathogen: The Salmonella Entry Toolkit

    Directory of Open Access Journals (Sweden)

    Peter J. Hume

    2017-08-01

    Full Text Available Salmonella causes disease in humans and animals ranging from mild self-limiting gastroenteritis to potentially life-threatening typhoid fever. Salmonellosis remains a considerable cause of morbidity and mortality globally, and hence imposes a huge socio-economic burden worldwide. A key property of all pathogenic Salmonella strains is the ability to invade non-phagocytic host cells. The major determinant of this invasiveness is a Type 3 Secretion System (T3SS, a molecular syringe that injects virulence effector proteins directly into target host cells. These effectors cooperatively manipulate multiple host cell signaling pathways to drive pathogen internalization. Salmonella does not only rely on these injected effectors, but also uses several other T3SS-independent mechanisms to gain entry into host cells. This review summarizes our current understanding of the methods used by Salmonella for cell invasion, with a focus on the host signaling networks that must be coordinately exploited for the pathogen to achieve its goal.

  4. Clostridium difficile is an autotrophic bacterial pathogen.

    Directory of Open Access Journals (Sweden)

    Michael Köpke

    Full Text Available During the last decade, Clostridium difficile infection showed a dramatic increase in incidence and virulence in the Northern hemisphere. This incessantly challenging disease is the leading cause of antibiotic-associated and nosocomial infectious diarrhea and became life-threatening especially among elderly people. It is generally assumed that all human bacterial pathogens are heterotrophic organisms, being either saccharolytic or proteolytic. So far, this has not been questioned as colonization of the human gut gives access to an environment, rich in organic nutrients. Here, we present data that C. difficile (both clinical and rumen isolates is also able to grow on CO2+H2 as sole carbon and energy source, thus representing the first identified autotrophic bacterial pathogen. Comparison of several different strains revealed high conservation of genes for autotrophic growth and showed that the ability to use gas mixtures for growth decreases or is lost upon prolonged culturing under heterotrophic conditions. The metabolic flexibility of C. difficile (heterotrophic growth on various substrates as well as autotrophy could allow the organism in the gut to avoid competition by niche differentiation and contribute to its survival when stressed or in unfavorable conditions that cause death to other bacteria. This may be an important trait for the pathogenicity of C. difficile.

  5. Host-pathogen interplay of Haemophilus ducreyi.

    Science.gov (United States)

    Janowicz, Diane M; Li, Wei; Bauer, Margaret E

    2010-02-01

    Haemophilus ducreyi, the causative agent of the sexually transmitted infection chancroid, is primarily a pathogen of human skin. During infection, H. ducreyi thrives extracellularly in a milieu of professional phagocytes and other antibacterial components of the innate and adaptive immune responses. This review summarizes our understanding of the interplay between this pathogen and its host that leads to development and persistence of disease. H. ducreyi expresses key virulence mechanisms to resist host defenses. The secreted LspA proteins are tyrosine-phosphorylated by host kinases, which may contribute to their antiphagocytic effector function. The serum resistance and adherence functions of DsrA map to separate domains of this multifunctional virulence factor. An influx transporter protects H. ducreyi from killing by the antimicrobial peptide LL37. Regulatory genes have been identified that may coordinate virulence factor expression during disease. Dendritic cells and natural killer cells respond to H. ducreyi and may be involved in determining the differential outcomes of infection observed in humans. A human model of H. ducreyi infection has provided insights into virulence mechanisms that allow this human-specific pathogen to survive immune pressures. Components of the human innate immune system may also determine the ultimate fate of H. ducreyi infection by driving either clearance of the organism or an ineffective response that allows disease progression.

  6. Combinatorial stresses kill pathogenic Candida species

    Science.gov (United States)

    Kaloriti, Despoina; Tillmann, Anna; Cook, Emily; Jacobsen, Mette; You, Tao; Lenardon, Megan; Ames, Lauren; Barahona, Mauricio; Chandrasekaran, Komelapriya; Coghill, George; Goodman, Daniel; Gow, Neil A. R.; Grebogi, Celso; Ho, Hsueh-Lui; Ingram, Piers; McDonagh, Andrew; De Moura, Alessandro P. S.; Pang, Wei; Puttnam, Melanie; Radmaneshfar, Elahe; Romano, Maria Carmen; Silk, Daniel; Stark, Jaroslav; Stumpf, Michael; Thiel, Marco; Thorne, Thomas; Usher, Jane; Yin, Zhikang; Haynes, Ken; Brown, Alistair J. P.

    2012-01-01

    Pathogenic microbes exist in dynamic niches and have evolved robust adaptive responses to promote survival in their hosts. The major fungal pathogens of humans, Candida albicans and Candida glabrata, are exposed to a range of environmental stresses in their hosts including osmotic, oxidative and nitrosative stresses. Significant efforts have been devoted to the characterization of the adaptive responses to each of these stresses. In the wild, cells are frequently exposed simultaneously to combinations of these stresses and yet the effects of such combinatorial stresses have not been explored. We have developed a common experimental platform to facilitate the comparison of combinatorial stress responses in C. glabrata and C. albicans. This platform is based on the growth of cells in buffered rich medium at 30°C, and was used to define relatively low, medium and high doses of osmotic (NaCl), oxidative (H 2O2) and nitrosative stresses (e.g., dipropylenetriamine (DPTA)-NONOate). The effects of combinatorial stresses were compared with the corresponding individual stresses under these growth conditions. We show for the first time that certain combinations of combinatorial stress are especially potent in terms of their ability to kill C. albicans and C. glabrata and/or inhibit their growth. This was the case for combinations of osmotic plus oxidative stress and for oxidative plus nitrosative stress. We predict that combinatorial stresses may be highly signif cant in host defences against these pathogenic yeasts. PMID:22463109

  7. The Venturia Apple Pathosystem: Pathogenicity Mechanisms and Plant Defense Responses

    Directory of Open Access Journals (Sweden)

    Gopaljee Jha

    2009-01-01

    Full Text Available Venturia inaequalis is the causal agent of apple scab, a devastating disease of apple. We outline several unique features of this pathogen which are useful for molecular genetics studies intended to understand plant-pathogen interactions. The pathogenicity mechanisms of the pathogen and overview of apple defense responses, monogenic and polygenic resistance, and their utilization in scab resistance breeding programs are also reviewed.

  8. Phosphorylation and proteome dynamics in pathogen-resistant tomato plants

    OpenAIRE

    Stulemeijer, I.J.E.

    2008-01-01

    Microbial plant pathogens impose a continuous threat on global food production. Similar to disease resistance in mammals, an innate immune system allows plants to recognise pathogens and swiftly activate defence. For the work described in this thesis, the interaction between tomato and the extracellular fungal pathogen Cladosporium fulvum serves as a model system to study host resistance and susceptibility in plant-pathogen interactions. Resistance to C. fulvum in tomato plants follows the ge...

  9. Host-pathogen interactions: A cholera surveillance system

    Energy Technology Data Exchange (ETDEWEB)

    Wright, Aaron T.

    2016-02-22

    Bacterial pathogen-secreted proteases may play a key role in inhibiting a potentially widespread host-pathogen interaction. Activity-based protein profiling enabled the identification of a major Vibrio cholerae serine protease that limits the ability of a host-derived intestinal lectin to bind to the bacterial pathogen in vivo.

  10. Comparison of procedures to evaluate the pathogenicity of ...

    African Journals Online (AJOL)

    Ceratocystis fimbriata sensu lato(s.l.) is an important pathogen of Eucalyptus. Pathogenicity of isolates has typically been evaluated by inoculating seedlings under greenhouse conditions. It is, however, not clear how accurately this reflects pathogenicity under field conditions. In this study, five techniques to potentially ...

  11. Intervention strategies for control of foodborne pathogens

    Science.gov (United States)

    Juneja, Vijay K.

    2004-03-01

    The increasing numbers of illnesses associated with foodborne pathogens such as Listeria monocytogenes and Escherichia coli O157:H7, has renewed concerns about food safety because of consumer preferences for minimally processed foods that offer convenience in availability and preparation. Accordingly, the need for better control of foodborne pathogens has been paramount in recent years. Mechanical removal of microorganisms from food can be accomplished by centrifugation, filtration, trimming and washing. Cleaning and sanitation strategies can be used for minimizing the access of microorganisms in foods from various sources. Other strategies for control of foodborne pathogens include established physical microbiocidal treatments such as ionizing radiation and heating. Research has continued to demonstrate that food irradiation is a suitable process to control and possibly eliminate foodborne pathogens, for example Listeria monocytogenes and Escherichia coli O157:H7, from a number of raw and cooked meat and poultry products. Heat treatment is the most common method in use today for the inactivation of microorganisms. Microorganisms can also be destroyed by nonthermal treatments, such as application of high hydrostatic pressure, pulsed electric fields, oscillating magnetic fields or a combination of physical processes such as heat-irradiation, or heat-high hydrostatic pressure, etc. Each of the non-thermal technologies has specific applications in terms of the types of food that can be processed. Both conventional and newly developed physical treatments can be used in combination for controlling foodborne pathogens and enhancing the safety and shelf life of foods. Recent research has focused on combining traditional preservation factors with emerging intervention technologies. However, many key issues still need to be addressed for combination preservation factors or technologies to be useful in the food industry to meet public demands for foods with enhanced safety

  12. Mycological assessment of sediments in Ligurian beaches in the Northwestern Mediterranean: pathogens and opportunistic pathogens.

    Science.gov (United States)

    Salvo, Vanessa-Sarah; Fabiano, Mauro

    2007-05-01

    Sediments of five Ligurian beaches in compliance with European Union bathing water regulations were studied based on the characteristics of the fungal assemblage during the tourism season. Among the 179 taxa of filamentous fungi isolated, 120 were opportunistic pathogens, such as Acremonium sp., and the genus Penicillium was also present as the pathogenic species P. citrinum. Furthermore, 5% of the total filamentous fungi belonged to the dermatophyte genus Microsporum, whose species can cause mycoses. Beach sediments showed elevated densities of opportunistic pathogens, of pathogenic filamentous fungi, and of yeasts during the tourism season. Although monitoring of beach sediments for microbiological contamination is not mandatory, and disease transmission from sediments has not yet been demonstrated, our study suggests that beach sediments may act as a reservoir of potential pathogens, including fungi. In addition, the mycoflora displayed high sensitivity to critical environmental situations in the beaches studied. Therefore, the fungal community can be a useful tool for assessing the quality of sandy beaches in terms of sanitary and environmental quality.

  13. Phylogeographic Diversity of Pathogenic and Non-Pathogenic Hantaviruses in Slovenia

    Science.gov (United States)

    Korva, Miša; Knap, Nataša; Resman Rus, Katarina; Fajs, Luka; Grubelnik, Gašper; Bremec, Matejka; Knapič, Tea; Trilar, Tomi; Avšič Županc, Tatjana

    2013-01-01

    Slovenia is a very diverse country from a natural geography point of view, with many different habitats within a relatively small area, in addition to major geological and climatic differences. It is therefore not surprising that several small mammal species have been confirmed to harbour hantaviruses: A. flavicollis (Dobrava virus), A. agrarius (Dobrava virus–Kurkino), M. glareolus (Puumala virus), S. areanus (Seewis virus), M. agrestis, M. arvalis and M. subterraneus (Tula virus). Three of the viruses, namely the Dobrava, Dobrava–Kurkino and Puumala viruses, cause disease in humans, with significant differences in the severity of symptoms. Due to changes in haemorrhagic fever with renal syndrome cases (HFRS) epidemiology, a detailed study on phylogenetic diversity and molecular epidemiology of pathogenic and non-pathogenic hantaviruses circulating in ecologically diverse endemic regions was performed. The study presents one of the largest collections of hantavirus L, M and S sequences obtained from hosts and patients within a single country. Several genetic lineages were determined for each hantavirus species, with higher diversity among non-pathogenic compared to pathogenic viruses. For pathogenic hantaviruses, a significant geographic clustering of human- and rodent-derived sequences was confirmed. Several geographic and ecological factors were recognized as influencing and limiting the formation of endemic areas. PMID:24335778

  14. Uncovering plant-pathogen crosstalk through apoplastic proteomic studies.

    Science.gov (United States)

    Delaunois, Bertrand; Jeandet, Philippe; Clément, Christophe; Baillieul, Fabienne; Dorey, Stéphan; Cordelier, Sylvain

    2014-01-01

    Plant pathogens have evolved by developing different strategies to infect their host, which in turn have elaborated immune responses to counter the pathogen invasion. The apoplast, including the cell wall and extracellular space outside the plasma membrane, is one of the first compartments where pathogen-host interaction occurs. The plant cell wall is composed of a complex network of polysaccharides polymers and glycoproteins and serves as a natural physical barrier against pathogen invasion. The apoplastic fluid, circulating through the cell wall and intercellular spaces, provides a means for delivering molecules and facilitating intercellular communications. Some plant-pathogen interactions lead to plant cell wall degradation allowing pathogens to penetrate into the cells. In turn, the plant immune system recognizes microbial- or damage-associated molecular patterns (MAMPs or DAMPs) and initiates a set of basal immune responses, including the strengthening of the plant cell wall. The establishment of defense requires the regulation of a wide variety of proteins that are involved at different levels, from receptor perception of the pathogen via signaling mechanisms to the strengthening of the cell wall or degradation of the pathogen itself. A fine regulation of apoplastic proteins is therefore essential for rapid and effective pathogen perception and for maintaining cell wall integrity. This review aims to provide insight into analyses using proteomic approaches of the apoplast to highlight the modulation of the apoplastic protein patterns during pathogen infection and to unravel the key players involved in plant-pathogen interaction.

  15. Identifying Pathogenicity Islands in Bacterial Pathogenomics Using Computational Approaches

    Directory of Open Access Journals (Sweden)

    Dongsheng Che

    2014-01-01

    Full Text Available High-throughput sequencing technologies have made it possible to study bacteria through analyzing their genome sequences. For instance, comparative genome sequence analyses can reveal the phenomenon such as gene loss, gene gain, or gene exchange in a genome. By analyzing pathogenic bacterial genomes, we can discover that pathogenic genomic regions in many pathogenic bacteria are horizontally transferred from other bacteria, and these regions are also known as pathogenicity islands (PAIs. PAIs have some detectable properties, such as having different genomic signatures than the rest of the host genomes, and containing mobility genes so that they can be integrated into the host genome. In this review, we will discuss various pathogenicity island-associated features and current computational approaches for the identification of PAIs. Existing pathogenicity island databases and related computational resources will also be discussed, so that researchers may find it to be useful for the studies of bacterial evolution and pathogenicity mechanisms.

  16. Evolution and genome architecture in fungal plant pathogens.

    Science.gov (United States)

    Möller, Mareike; Stukenbrock, Eva H

    2017-12-01

    The fungal kingdom comprises some of the most devastating plant pathogens. Sequencing the genomes of fungal pathogens has shown a remarkable variability in genome size and architecture. Population genomic data enable us to understand the mechanisms and the history of changes in genome size and adaptive evolution in plant pathogens. Although transposable elements predominantly have negative effects on their host, fungal pathogens provide prominent examples of advantageous associations between rapidly evolving transposable elements and virulence genes that cause variation in virulence phenotypes. By providing homogeneous environments at large regional scales, managed ecosystems, such as modern agriculture, can be conducive for the rapid evolution and dispersal of pathogens. In this Review, we summarize key examples from fungal plant pathogen genomics and discuss evolutionary processes in pathogenic fungi in the context of molecular evolution, population genomics and agriculture.

  17. Comparative analysis of lipopolysaccharides of pathogenic and intermediately pathogenic Leptospira species.

    Science.gov (United States)

    Patra, Kailash P; Choudhury, Biswa; Matthias, Michael M; Baga, Sheyenne; Bandyopadhya, Keya; Vinetz, Joseph M

    2015-10-30

    Lipopolysaccharides (LPS) are complex, amphipathic biomolecules that constitute the major surface component of Gram-negative bacteria. Leptospira, unlike other human-pathogenic spirochetes, produce LPS, which is fundamental to the taxonomy of the genus, involved in host-adaption and also the target of diagnostic antibodies. Despite its significance, little is known of Leptospira LPS composition and carbohydrate structure among different serovars. LPS from Leptospira interrogans serovar Copenhageni strain L1-130, a pathogenic species, and L. licerasiae serovar Varillal strain VAR 010, an intermediately pathogenic species, were studied. LPS prepared from aqueous and phenol phases were analyzed separately. L. interrogans serovar Copenhageni has additional sugars not found in L. licerasiae serovar Varillal, including fucose (2.7%), a high amount of GlcNAc (12.3%), and two different types of dideoxy HexNAc. SDS-PAGE indicated that L. interrogans serovar Copenhageni LPS had a far higher molecular weight and complexity than that of L. licerasiae serovar Varillal. Chemical composition showed that L. interrogans serovar Copenhageni LPS has an extended O-antigenic polysaccharide consisting of sugars, not present in L. licerasiae serovar Varillal. Arabinose, xylose, mannose, galactose and L-glycero-D-mannoheptose were detected in both the species. Fatty acid analysis by gas chromatography-mass spectrometry (GC-MS) showed the presence of hydroxypalmitate (3-OH-C16:0) only in L. interrogans serovar Copenhageni. Negative staining electron microscopic examination of LPS showed different filamentous morphologies in L. interrogans serovar Copenhageni vs. L. licerasiae serovar Varillal. This comparative biochemical analysis of pathogenic and intermediately pathogenic Leptospira LPS reveals important carbohydrate and lipid differences that underlie future work in understanding the mechanisms of host-adaptation, pathogenicity and vaccine development in leptospirosis.

  18. Candida glabrata: an emerging oral opportunistic pathogen.

    Science.gov (United States)

    Li, L; Redding, S; Dongari-Bagtzoglou, A

    2007-03-01

    Following the widespread use of immunosuppressive therapy and broad-spectrum antimycotic prophylaxis, C. glabrata has emerged as an important opportunistic pathogen in the oral mucosa. In the past, studies on the virulence factors and host-pathogen interactions of this organism were scarce, but continued to rise in recent years. Denture-wearing, immunosuppression, antibiotic therapy, and aging are risk factors for oral colonization or infection with C. glabrata. Compared with C. albicans, C. glabrata exhibits lower oral keratinocyte-adherence capacity, but higher denture-surface-adherence ability. The role of extracellular hydrolase production in the virulence of this organism does not appear to be as important as it is in C. albicans pathogenesis. Although traditionally thought of as a non-transforming yeast organism, both phenotypic switching and pseudohyphal formation have recently been identified in C. glabrata, but their role in pathogenesis is not known. With the exception of granulocyte monocyte colony-stimulating factor, C. glabrata triggers a lower proinflammatory cytokine response in oral epithelial cells than does C. albicans, in a strain-dependent manner. C. glabrata is less susceptible to killing by human beta-defensins than is C. albicans and exhibits various degrees of resistance to the antifungal activity of salivary histatins and mucins. In addition, C. glabrata possesses both innate and acquired resistance against antifungal drugs, due to its ability to modify ergosterol biosynthesis, mitochondrial function, or antifungal efflux. This resistance allows for its relative overgrowth over other susceptible species and may contribute to the recent emergence of C. glabrata infections in chronically immunocompromised populations. Further investigations on the virulence and host-pathogen interactions of C. glabrata are needed to better define the pathogenesis of oral C. glabrata infection in susceptible hosts.

  19. Lawrence Livermore National Laboratory Workshop Characterization of Pathogenicity, Virulence and Host-Pathogen Interactions

    Energy Technology Data Exchange (ETDEWEB)

    Krishnan, A

    2006-08-30

    The threats of bio-terrorism and newly emerging infectious diseases pose serious challenges to the national security infrastructure. Rapid detection and diagnosis of infectious disease in human populations, as well as characterizing pathogen biology, are critical for reducing the morbidity and mortality associated with such threats. One of the key challenges in managing an infectious disease outbreak, whether through natural causes or acts of overt terrorism, is detection early enough to initiate effective countermeasures. Much recent attention has been directed towards the utility of biomarkers or molecular signatures that result from the interaction of the pathogen with the host for improving our ability to diagnose and mitigate the impact of a developing infection during the time window when effective countermeasures can be instituted. Host responses may provide early signals in blood even from localized infections. Multiple innate and adaptive immune molecules, in combination with other biochemical markers, may provide disease-specific information and new targets for countermeasures. The presence of pathogen specific markers and an understanding of the molecular capabilities and adaptations of the pathogen when it interacts with its host may likewise assist in early detection and provide opportunities for targeting countermeasures. An important question that needs to be addressed is whether these molecular-based approaches will prove useful for early diagnosis, complement current methods of direct agent detection, and aid development and use of countermeasures. Lawrence Livermore National Laboratory (LLNL) will host a workshop to explore the utility of host- and pathogen-based molecular diagnostics, prioritize key research issues, and determine the critical steps needed to transition host-pathogen research to tools that can be applied towards a more effective national bio-defense strategy. The workshop will bring together leading researchers/scientists in the

  20. Bacteriophages in the control of pathogenic vibrios

    DEFF Research Database (Denmark)

    Plaza, Nicolás; Castillo Bermúdez, Daniel Elías; Perez-Reytor, Diliana

    2018-01-01

    constitute a continuing threat for aquaculture. Moreover, the continuous use of antibiotics has been accompanied by an emergence of antibiotic resistance in Vibrio species, implying a necessity for efficient treatments. One promising alternative that emerges is the use of lytic bacteriophages; however......, there are some drawbacks that should be overcome to make phage therapy a widely accepted method. In this work, we discuss about the major pathogenic Vibrio species and the progress, benefits and disadvantages that have been detected during the experimental use of bacteriophages to their control....

  1. Campylobacter ureolyticus: an emerging gastrointestinal pathogen?

    LENUS (Irish Health Repository)

    Bullman, Susan

    2011-03-01

    A total of 7194 faecal samples collected over a 1-year period from patients presenting with diarrhoea were screened for Campylobacter spp. using EntericBio(®) , a multiplex-PCR system. Of 349 Campylobacter-positive samples, 23.8% were shown to be Campylobacter ureolyticus, using a combination of 16S rRNA gene analysis and highly specific primers targeting the HSP60 gene of this organism. This is, to the best of our knowledge, the first report of C. ureolyticus in the faeces of patients presenting with gastroenteritis and may suggest a role for this organism as an emerging enteric pathogen.

  2. Specialized Pathogen of a Social Insect

    DEFF Research Database (Denmark)

    Małagocka, Joanna

    provide a game changing component that shapes the interaction in quite a unique way. This thesis explores some of the aspects of biology of host-pathogen interaction between red wood ants, F. polyctena, and the fungus P. formicae. First, the taxonomy of the fungus is studied and some nomenclatural issues...... that ants actively remove fungus-killed cadavers is documented and further explored in this thesis. I establish the effect of this behavior on raw numbers of cadavers present around an ant colony by detailed mapping of colony surroundings for three subsequent days, twice a day, three times during the season...

  3. Bacterial pathogens in a reactor cooling reservoir

    International Nuclear Information System (INIS)

    Kasweck, K.L.; Fliermans, C.B.

    1978-01-01

    The results of the sampling in both Par Pond and Clark Hill Reservoir are given. The frequency of isolation is a qualitative parameter which indicates how often the specified bacterium was isolated from each habitat. Initial scoping experiments demonstrated that a wider variety of pathogenic bacteria occur in Par Pond than in Clark Hill Reservoir. Such findings are interesting because Par Pond does not receive any human wastes directly, yet bacteria generally associated with human wastes are more frequently isolated from Par Pond. Previous studies have demonstrated that certain non-spore-forming enteric bacteria do not survive the intense heat associated with the cooling water when the reactor is operating. However, even when the reactor is not operating, cooling water, consisting of 10% makeup water from Savannah River, continues to flow into Par Pond. This flow provides a source of bacteria which inoculate Par Pond. Once the reactor is again operating, these same bacteria appear to be able to survive and grow within the Par Pond system. Thus, Par Pond and the associated lakes and canals of the Par Pond system provide a pool of pathogens that normally would not survive in natural waters

  4. Vibrio parahaemolyticus- An emerging foodborne pathogen

    Directory of Open Access Journals (Sweden)

    S Nelapati

    2012-02-01

    Full Text Available Vibrio parahaemolyticus is a halophilic gram negative, motile, oxidase positive, straight or curved rod-shaped, facultative anaerobic bacteria that occur naturally in the marine environment. They form part of the indigenous microflora of aquatic habitats of various salinity and are the major causative agents for some of the most serious diseases in fish, shellfish and penacid shrimp. This human pathogen causes acute gastroenteritis characterized by diarrhea, vomiting and abdominal cramps through consumption of contaminated raw fish or shellfish. V. parahaemolyticus is the leading cause of gastroenteritis due to the consumption of seafood worldwide. The incidence of V. parahaemolyticus infection has been increasing in many parts of the world, due to the emergence of O3:K6 serotype carrying the tdh gene which is responsible for most outbreaks worldwide. The pathogenicity of this organism is closely correlated with the Kanagawa phenomenon (KP + due to production of Kanagawa hemolysin or the thermostable direct hemolysin (TDH. The TDH and TRH (TDH-related hemolysin encoded by tdh and trh genes are considered to be important virulence factors. [Vet. World 2012; 5(1.000: 48-63

  5. Fusarium species as pathogen on orchids.

    Science.gov (United States)

    Srivastava, Shikha; Kadooka, Chris; Uchida, Janice Y

    2018-03-01

    The recent surge in demand for exotic ornamental crops such as orchids has led to a rise in international production, and a sharp increase in the number of plant and plant products moving between countries. Along with the plants, diseases are also being transported and introduced into new areas. Fusarium is one of the major diseases causing pathogens infecting orchids that is spreading through international trade. Studies have identified several species of Fusarium associated with orchids, some are pathogenic and cause symptoms such as leaf and flower spots, leaf or sheath blights, pseudostem or root rots, and wilts. Infection and damage caused by Fusarium reduces the quality of plants and flowers, and can cause severe economic losses. This review documents the current status of the Fusarium-orchid interaction, and illustrates challenges and future perspectives based on the available literature. This review is the first of Fusarium and orchid interactions, and integrates diverse results that both furthers the understanding and knowledge of this disease complex, and will enable the development of effective disease management practices. Copyright © 2017 Elsevier GmbH. All rights reserved.

  6. Planning for compliance: OSHA's bloodborne pathogen rule.

    Science.gov (United States)

    Bednar, B; Duke, M C

    1990-11-01

    Overall, the bloodborne pathogen rule constitutes a reasonable response to a significant threat to workplace safety. The risks to dialysis workers from HBV and HIV must be minimized or eliminated and the rule is generally consistent with the consensus approach. Unfortunately for dialysis providers, the rule is not exempt from the law of unintended consequences: government regulation will always have impact beyond its object. Promulgation of the final rule will immediately increase the expenses of dialysis providers. Additionally, the enormity of the HBV and HIV problem coupled with the open-ended nature of the rule's key provisions will almost certainly bring additional costs. So long as dialysis reimbursement remains flat, the unintended consequence of the bloodborne pathogen rule may be to quicken the pace of consolidation in the dialysis service market. The added burden of compliance may be too much for small independent facilities. Only large chains may have the resources to comply and survive. To forestall this effect and to provide employees with maximum protection, all dialysis providers should plan now for compliance.

  7. Epidemiology of Rhodotorula: An Emerging Pathogen

    Science.gov (United States)

    Wirth, Fernanda; Goldani, Luciano Z.

    2012-01-01

    This is an updated paper focusing on the general epidemiological aspects of Rhodotorula in humans, animals, and the environment. Previously considered nonpathogenic, Rhodotorula species have emerged as opportunistic pathogens that have the ability to colonise and infect susceptible patients. Rhodotorula species are ubiquitous saprophytic yeasts that can be recovered from many environmental sources. Several authors describe the isolation of this fungus from different ecosystems, including sites with unfavourable conditions. Compared to R. mucilaginosa, R. glutinis and R. minuta are less frequently isolated from natural environments. Among the few references to the pathogenicity of Rhodotorula spp. in animals, there are several reports of an outbreak of skin infections in chickens and sea animals and lung infections and otitis in sheep and cattle. Most of the cases of infection due to Rhodotorula in humans were fungemia associated with central venous catheter (CVC) use. The most common underlying diseases included solid and haematologic malignancies in patients who were receiving corticosteroids and cytotoxic drugs, the presence of CVC, and the use of broad-spectrum antibiotics. Unlike fungemia, some of the other localised infections caused by Rhodotorula, including meningeal, skin, ocular, peritoneal, and prosthetic joint infections, are not necessarily linked to the use of CVCs or immunosuppression. PMID:23091485

  8. Emerging microbial biocontrol strategies for plant pathogens.

    Science.gov (United States)

    Syed Ab Rahman, Sharifah Farhana; Singh, Eugenie; Pieterse, Corné M J; Schenk, Peer M

    2018-02-01

    To address food security, agricultural yields must increase to match the growing human population in the near future. There is now a strong push to develop low-input and more sustainable agricultural practices that include alternatives to chemicals for controlling pests and diseases, a major factor of heavy losses in agricultural production. Based on the adverse effects of some chemicals on human health, the environment and living organisms, researchers are focusing on potential biological control microbes as viable alternatives for the management of pests and plant pathogens. There is a growing body of evidence that demonstrates the potential of leaf and root-associated microbiomes to increase plant efficiency and yield in cropping systems. It is important to understand the role of these microbes in promoting growth and controlling diseases, and their application as biofertilizers and biopesticides whose success in the field is still inconsistent. This review focusses on how biocontrol microbes modulate plant defense mechanisms, deploy biocontrol actions in plants and offer new strategies to control plant pathogens. Apart from simply applying individual biocontrol microbes, there are now efforts to improve, facilitate and maintain long-term plant colonization. In particular, great hopes are associated with the new approaches of using "plant-optimized microbiomes" (microbiome engineering) and establishing the genetic basis of beneficial plant-microbe interactions to enable breeding of "microbe-optimized crops". Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Burkholderia glumae: next major pathogen of rice?

    Science.gov (United States)

    Ham, Jong Hyun; Melanson, Rebecca A; Rush, Milton C

    2011-05-01

    Burkholderia glumae causes bacterial panicle blight of rice, which is an increasingly important disease problem in global rice production. Toxoflavin and lipase are known to be major virulence factors of this pathogen, and their production is dependent on the TofI/TofR quorum-sensing system, which is mediated by N-octanoyl homoserine lactone. Flagellar biogenesis and a type III secretion system are also required for full virulence of B. glumae. Bacterial panicle blight is thought to be caused by seed-borne B. glumae; however, its disease cycle is not fully understood. In spite of its economic importance, neither effective control measures for bacterial panicle blight nor rice varieties showing complete resistance to the disease are currently available. A better understanding of the molecular mechanisms underlying B. glumae virulence and of the rice defence mechanisms against the pathogen would lead to the development of better methods of disease control for bacterial panicle blight. Bacteria; Proteobacteria; Betaproteobacteria; Burkholderiales; Burkholderiaceae; Burkholderia. Gram-negative, capsulated, motile, lophotrichous flagella, pectolytic. Aborted seed, empty grains as a result of failure of grain filling, brown spots on panicles, seedling rot. Seed sterilization, planting partially resistant lines (no completely resistant line is available). KNOWN VIRULENCE FACTORS: Toxoflavin, lipase, type III effectors. © 2010 LSU AGCENTER. MOLECULAR PLANT PATHOLOGY © 2010 BSPP AND BLACKWELL PUBLISHING LTD.

  10. An emerging cyberinfrastructure for biodefense pathogen and pathogen-host data.

    Science.gov (United States)

    Zhang, C; Crasta, O; Cammer, S; Will, R; Kenyon, R; Sullivan, D; Yu, Q; Sun, W; Jha, R; Liu, D; Xue, T; Zhang, Y; Moore, M; McGarvey, P; Huang, H; Chen, Y; Zhang, J; Mazumder, R; Wu, C; Sobral, B

    2008-01-01

    The NIAID-funded Biodefense Proteomics Resource Center (RC) provides storage, dissemination, visualization and analysis capabilities for the experimental data deposited by seven Proteomics Research Centers (PRCs). The data and its publication is to support researchers working to discover candidates for the next generation of vaccines, therapeutics and diagnostics against NIAID's Category A, B and C priority pathogens. The data includes transcriptional profiles, protein profiles, protein structural data and host-pathogen protein interactions, in the context of the pathogen life cycle in vivo and in vitro. The database has stored and supported host or pathogen data derived from Bacillus, Brucella, Cryptosporidium, Salmonella, SARS, Toxoplasma, Vibrio and Yersinia, human tissue libraries, and mouse macrophages. These publicly available data cover diverse data types such as mass spectrometry, yeast two-hybrid (Y2H), gene expression profiles, X-ray and NMR determined protein structures and protein expression clones. The growing database covers over 23 000 unique genes/proteins from different experiments and organisms. All of the genes/proteins are annotated and integrated across experiments using UniProt Knowledgebase (UniProtKB) accession numbers. The web-interface for the database enables searching, querying and downloading at the level of experiment, group and individual gene(s)/protein(s) via UniProtKB accession numbers or protein function keywords. The system is accessible at http://www.proteomicsresource.org/.

  11. Molecular aspects of avirulence and pathogenicity of the tomato pathogen Cladosporium fulvum

    NARCIS (Netherlands)

    Ackerveken, van den G.F.J.M.

    1993-01-01

    The molecular understanding of host-pathogen interactions and particularly of specificity forms the basis for studying plant resistance. Understanding why a certain plant species or cultivar is susceptible and why other species or cultivars are resistant is of great importance in order to

  12. Biological characteristics and pathogenicity of a highly pathogenic Shewanella marisflavi infected sea cucumber (Apostichopus uaponicus)

    Science.gov (United States)

    Shewanella marisflavi isolate AP629 was characterized as a novel pathogen of sea cucumber. The LD50 values (14 days) in sea cucumber and swordtail fish were 3.89 × 106 and 4.85 × 104 CFU g-1 body weight, respectively. Studies on S. marisflavi had been conducted, including morphology, physiological a...

  13. Yeast cell differentiation: Lessons from pathogenic and non-pathogenic yeasts

    Czech Academy of Sciences Publication Activity Database

    Pálková, Z.; Váchová, Libuše

    2016-01-01

    Roč. 57, SEP (2016), s. 110-119 ISSN 1084-9521 R&D Projects: GA ČR GA13-08605S; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:61388971 Keywords : Pathogenic yeasts * Biofilms and colonies * Cell differentiation Subject RIV: EE - Microbiology, Virology Impact factor: 6.614, year: 2016

  14. Prediction of molecular mimicry candidates in human pathogenic bacteria.

    Science.gov (United States)

    Doxey, Andrew C; McConkey, Brendan J

    2013-08-15

    Molecular mimicry of host proteins is a common strategy adopted by bacterial pathogens to interfere with and exploit host processes. Despite the availability of pathogen genomes, few studies have attempted to predict virulence-associated mimicry relationships directly from genomic sequences. Here, we analyzed the proteomes of 62 pathogenic and 66 non-pathogenic bacterial species, and screened for the top pathogen-specific or pathogen-enriched sequence similarities to human proteins. The screen identified approximately 100 potential mimicry relationships including well-characterized examples among the top-scoring hits (e.g., RalF, internalin, yopH, and others), with about 1/3 of predicted relationships supported by existing literature. Examination of homology to virulence factors, statistically enriched functions, and comparison with literature indicated that the detected mimics target key host structures (e.g., extracellular matrix, ECM) and pathways (e.g., cell adhesion, lipid metabolism, and immune signaling). The top-scoring and most widespread mimicry pattern detected among pathogens consisted of elevated sequence similarities to ECM proteins including collagens and leucine-rich repeat proteins. Unexpectedly, analysis of the pathogen counterparts of these proteins revealed that they have evolved independently in different species of bacterial pathogens from separate repeat amplifications. Thus, our analysis provides evidence for two classes of mimics: complex proteins such as enzymes that have been acquired by eukaryote-to-pathogen horizontal transfer, and simpler repeat proteins that have independently evolved to mimic the host ECM. Ultimately, computational detection of pathogen-specific and pathogen-enriched similarities to host proteins provides insights into potentially novel mimicry-mediated virulence mechanisms of pathogenic bacteria.

  15. A network approach to predict pathogenic genes for Fusarium graminearum.

    Science.gov (United States)

    Liu, Xiaoping; Tang, Wei-Hua; Zhao, Xing-Ming; Chen, Luonan

    2010-10-04

    Fusarium graminearum is the pathogenic agent of Fusarium head blight (FHB), which is a destructive disease on wheat and barley, thereby causing huge economic loss and health problems to human by contaminating foods. Identifying pathogenic genes can shed light on pathogenesis underlying the interaction between F. graminearum and its plant host. However, it is difficult to detect pathogenic genes for this destructive pathogen by time-consuming and expensive molecular biological experiments in lab. On the other hand, computational methods provide an alternative way to solve this problem. Since pathogenesis is a complicated procedure that involves complex regulations and interactions, the molecular interaction network of F. graminearum can give clues to potential pathogenic genes. Furthermore, the gene expression data of F. graminearum before and after its invasion into plant host can also provide useful information. In this paper, a novel systems biology approach is presented to predict pathogenic genes of F. graminearum based on molecular interaction network and gene expression data. With a small number of known pathogenic genes as seed genes, a subnetwork that consists of potential pathogenic genes is identified from the protein-protein interaction network (PPIN) of F. graminearum, where the genes in the subnetwork are further required to be differentially expressed before and after the invasion of the pathogenic fungus. Therefore, the candidate genes in the subnetwork are expected to be involved in the same biological processes as seed genes, which imply that they are potential pathogenic genes. The prediction results show that most of the pathogenic genes of F. graminearum are enriched in two important signal transduction pathways, including G protein coupled receptor pathway and MAPK signaling pathway, which are known related to pathogenesis in other fungi. In addition, several pathogenic genes predicted by our method are verified in other pathogenic fungi, which

  16. A new oligonucleotide microarray for detection of pathogenic and non-pathogenic Legionella spp.

    Directory of Open Access Journals (Sweden)

    Boyang Cao

    Full Text Available Legionella pneumophila has been recognized as the major cause of legionellosis since the discovery of the deadly disease. Legionella spp. other than L. pneumophila were later found to be responsible to many non-pneumophila infections. The non-L. pneumophila infections are likely under-detected because of a lack of effective diagnosis. In this report, we have sequenced the 16S-23S rRNA gene internal transcribed spacer (ITS of 10 Legionella species and subspecies, including L. anisa, L. bozemanii, L. dumoffii, L. fairfieldensis, L. gormanii, L. jordanis, L. maceachernii, L. micdadei, L. pneumophila subspp. fraseri and L. pneumophila subspp. pasculleii, and developed a rapid oligonucleotide microarray detection technique accordingly to identify 12 most common Legionella spp., which consist of 11 pathogenic species of L. anisa, L. bozemanii, L. dumoffii, L. gormanii, L. jordanis, L. longbeachae, L. maceachernii, L. micdadei, and L. pneumophila (including subspp. pneumophila, subspp. fraseri, and subspp. pasculleii and one non-pathogenic species, L. fairfieldensis. Twenty-nine probes that reproducibly detected multiple Legionella species with high specificity were included in the array. A total of 52 strains, including 30 target pathogens and 22 non-target bacteria, were used to verify the oligonucleotide microarray assay. The sensitivity of the detection was at 1.0 ng with genomic DNA or 13 CFU/100 mL with Legionella cultures. The microarray detected seven samples of air conditioner-condensed water with 100% accuracy, validating the technique as a promising method for applications in basic microbiology, clinical diagnosis, food safety, and epidemiological surveillance. The phylogenetic study based on the ITS has also revealed that the non-pathogenic L. fairfieldensis is the closest to L. pneumophila than the nine other pathogenic Legionella spp.

  17. A New Oligonucleotide Microarray for Detection of Pathogenic and Non-Pathogenic Legionella spp.

    Science.gov (United States)

    Cao, Boyang; Liu, Xiangqian; Yu, Xiang; Chen, Min; Feng, Lu; Wang, Lei

    2014-01-01

    Legionella pneumophila has been recognized as the major cause of legionellosis since the discovery of the deadly disease. Legionella spp. other than L. pneumophila were later found to be responsible to many non-pneumophila infections. The non-L. pneumophila infections are likely under-detected because of a lack of effective diagnosis. In this report, we have sequenced the 16S-23S rRNA gene internal transcribed spacer (ITS) of 10 Legionella species and subspecies, including L. anisa, L. bozemanii, L. dumoffii, L. fairfieldensis, L. gormanii, L. jordanis, L. maceachernii, L. micdadei, L. pneumophila subspp. fraseri and L. pneumophila subspp. pasculleii, and developed a rapid oligonucleotide microarray detection technique accordingly to identify 12 most common Legionella spp., which consist of 11 pathogenic species of L. anisa, L. bozemanii, L. dumoffii, L. gormanii, L. jordanis, L. longbeachae, L. maceachernii, L. micdadei, and L. pneumophila (including subspp. pneumophila, subspp. fraseri, and subspp. pasculleii) and one non-pathogenic species, L. fairfieldensis. Twenty-nine probes that reproducibly detected multiple Legionella species with high specificity were included in the array. A total of 52 strains, including 30 target pathogens and 22 non-target bacteria, were used to verify the oligonucleotide microarray assay. The sensitivity of the detection was at 1.0 ng with genomic DNA or 13 CFU/100 mL with Legionella cultures. The microarray detected seven samples of air conditioner-condensed water with 100% accuracy, validating the technique as a promising method for applications in basic microbiology, clinical diagnosis, food safety, and epidemiological surveillance. The phylogenetic study based on the ITS has also revealed that the non-pathogenic L. fairfieldensis is the closest to L. pneumophila than the nine other pathogenic Legionella spp. PMID:25469776

  18. ClinGen Pathogenicity Calculator: a configurable system for assessing pathogenicity of genetic variants.

    Science.gov (United States)

    Patel, Ronak Y; Shah, Neethu; Jackson, Andrew R; Ghosh, Rajarshi; Pawliczek, Piotr; Paithankar, Sameer; Baker, Aaron; Riehle, Kevin; Chen, Hailin; Milosavljevic, Sofia; Bizon, Chris; Rynearson, Shawn; Nelson, Tristan; Jarvik, Gail P; Rehm, Heidi L; Harrison, Steven M; Azzariti, Danielle; Powell, Bradford; Babb, Larry; Plon, Sharon E; Milosavljevic, Aleksandar

    2017-01-12

    The success of the clinical use of sequencing based tests (from single gene to genomes) depends on the accuracy and consistency of variant interpretation. Aiming to improve the interpretation process through practice guidelines, the American College of Medical Genetics and Genomics (ACMG) and the Association for Molecular Pathology (AMP) have published standards and guidelines for the interpretation of sequence variants. However, manual application of the guidelines is tedious and prone to human error. Web-based tools and software systems may not only address this problem but also document reasoning and supporting evidence, thus enabling transparency of evidence-based reasoning and resolution of discordant interpretations. In this report, we describe the design, implementation, and initial testing of the Clinical Genome Resource (ClinGen) Pathogenicity Calculator, a configurable system and web service for the assessment of pathogenicity of Mendelian germline sequence variants. The system allows users to enter the applicable ACMG/AMP-style evidence tags for a specific allele with links to supporting data for each tag and generate guideline-based pathogenicity assessment for the allele. Through automation and comprehensive documentation of evidence codes, the system facilitates more accurate application of the ACMG/AMP guidelines, improves standardization in variant classification, and facilitates collaborative resolution of discordances. The rules of reasoning are configurable with gene-specific or disease-specific guideline variations (e.g. cardiomyopathy-specific frequency thresholds and functional assays). The software is modular, equipped with robust application program interfaces (APIs), and available under a free open source license and as a cloud-hosted web service, thus facilitating both stand-alone use and integration with existing variant curation and interpretation systems. The Pathogenicity Calculator is accessible at http

  19. Aerobic vaginal pathogens and their sensitivity pattern.

    Science.gov (United States)

    Mumtaz, Shamim; Ahmad, Mumtaz; Aftab, Irum; Akhtar, Naeem; ul Hassan, Masood; Hamid, Abdul

    2008-01-01

    The vaginal flora is a complicated environment, containing dozens of microbiological species in variable quantities and relative proportions. The frequent cause of vaginal discharge is an infection or colonization with different microorganisms. Some pathologic conditions causing vaginitis are well defined yet, 7-72% of women with vaginitis may remain undiagnosed and such forms of abnormal vaginal flora neither considered as normal, nor can be called bacterial vaginosis have been termed as 'intermediate flora' and its management probably differ from that of bacterial vaginosis. It is of crucial importance in pregnant females at risk of preterm delivery. The present study has been conducted especially to elucidate this type of aerobic vaginal isolates and their culture and sensitivity towards currently used antibiotics. This study was conducted at the Microbiology Department of Fauji Foundation Hospital, Rawalpindi over a period of two years (April 2004-March 2006). One thousand, nine hundred and twenty three high vaginal swabs, both from indoor and outdoor patients were collected, cultured and their susceptibility to various antibiotics was determined. Significant growth was obtained in 731 samples. The highest frequency of infection (39.5%) was observed at 31-40 years followed by 41-50 years (35.8%). About 76% were from outdoor and 24% were from indoor patients. Staphylococcus aureus was the most prevalent vaginal pathogen at 11-60 yrs & with highest prevalence at 31-40 years followed by 41-50 years. It was a predominant pathogen in both indoor (35%) as well as outdoor (41.6%) patients, followed by enteric gram-negative bacilli and other gram-positive cocci. There were very few antibiotics among the conventionally available aminoglycosides, third generation cephalosporins, penicillin, quinolones, sulfonamides and tetracyclines possessing good sensitivity (> 80%) against any one the common aerobic vaginal pathogens. The effective chemotherapeutics agents belong to

  20. SILAC-based comparative analysis of pathogenic Escherichia coli secretomes

    DEFF Research Database (Denmark)

    Boysen, Anders; Borch, Jonas; Krogh, Thøger Jensen

    2015-01-01

    Comparative studies of pathogenic bacteria and their non-pathogenic counterparts has led to the discovery of important virulence factors thereby generating insight into mechanisms of pathogenesis. Protein-based antigens for vaccine development are primarily selected among unique virulence...... experimental approach. In addition we find proteins that are not unique to the pathogenic strains but expressed at levels different from the commensal strain, including the colonization factor YghJ and the surface adhesin antigen 43, which is involved in pathogenesis of other Gram-negative bacteria......-related factors produced by the pathogen of interest. However, recent work indicates that proteins that are not unique to the pathogen but instead selectively expressed compared to its non-pathogenic counterpart could also be vaccine candidates or targets for drug development. Modern methods in quantitative...

  1. Pseudomnas syringae – a Pathogen of Fruit Trees in Serbia

    Directory of Open Access Journals (Sweden)

    Veljko Gavrilović

    2009-01-01

    Full Text Available Data about symptomatology, pathogenicity and bacteriological characteristics of Pseudomonas syringae, and PCR methods for fast and reliable detection of the pathogen are given in this paper. P. syringae has been experimentaly proved as a pathogen of pear, apple, apricot, plum cherry, and raspberry, and pathogen strains have also been isolated from necrotic peach buds. Two pathogen varieties, syringae and morsprunorum, were found in our research in Serbia, the former being dominant on fruit trees.The most reliable method for detection of this bacteria is PCR, using BOX and REP primers. This method has also revealed significant differences among the strains originating from fruit trees in Serbia. Thus, it was proved that the population of P. syringae in Serbia is heterogeneous, which is very important for future epidemiologocal studies. Control of this pathogen includes mechanical, cultural and chemical measures, but integrated approach is very important for sustainable control.

  2. Subversion of inflammasome activation and pyroptosis by pathogenic bacteria

    Directory of Open Access Journals (Sweden)

    Larissa D Cunha

    2013-11-01

    Full Text Available Activation of the inflammasome occurs in response to a notably high number of pathogenic microbes and is a broad innate immune response that effectively contributes to restriction of pathogen replication and generation of adaptive immunity. Activation of these platforms leads to caspase-1- and/or caspase-11-dependent secretion of proteins, including cytokines, and induction of a specific form of cell death called pyroptosis, which directly or indirectly contribute for restriction of pathogen replication. Not surprisingly, bona fide intracellular pathogens developed strategies for manipulation of cell death to guarantee intracellular replication. In this sense, the remarkable advances in the knowledge of the inflammasome field have been accompanied by several reports characterizing the inhibition of this platform by several pathogenic bacteria. Herein, we review some processes used by pathogenic bacteria, including Yersinia spp., Pseudomonas aeruginosa, Vibrio parahaemolyticus, Chlamydia trachomatis, Francisella tularensis, Shigella flexneri, Legionella pneumophila and Coxiella burnetii to evade the activation of the inflammasome and the induction of pyroptosis.

  3. Social barriers to pathogen transmission in wild animal populations

    Energy Technology Data Exchange (ETDEWEB)

    Loehle, C.

    1995-03-01

    Diseases and pathogens are receiving increasing recognition as sources of mortality in animal populations. Immune system strength is clearly important in fending off pathogen attack. Physical barriers to pathogen entry are also important. Various individual behaviors are efficacious in reducing contact with diseases and pests. This paper focuses on a fourth mode of defense: social barriers to transmission. Various social behaviors have pathogen transmission consequences. Selective pressures on these social behaviors may therefore exist. Effects on pathogen transmission of mating strategies, social avoidance, group size, group isolation, and other behaviors are explored. It is concluded that many of these behaviors may have been affected by selection pressures to reduce transmission of pathogens. 84 refs., 1 tab.

  4. Urbanization Increases Pathogen Pressure on Feral and Managed Honey Bees

    OpenAIRE

    Youngsteadt, Elsa; Appler, R. Holden; L?pez-Uribe, Margarita M.; Tarpy, David R.; Frank, Steven D.

    2015-01-01

    Given the role of infectious disease in global pollinator decline, there is a need to understand factors that shape pathogen susceptibility and transmission in bees. Here we ask how urbanization affects the immune response and pathogen load of feral and managed colonies of honey bees (Apis mellifera Linnaeus), the predominant economically important pollinator worldwide. Using quantitative real-time PCR, we measured expression of 4 immune genes and relative abundance of 10 honey bee pathogens....

  5. AN INVESTIGATION ON PATHOGENIC VIBRIOS DISTRIBUTION IN DOMESTIC WASTEWATER

    OpenAIRE

    A. Almasi

    2005-01-01

    Municipal wastewater is one of the most important pollution sources for water supply resources. Identification and enumeration of pathogenic agents particularly pathogenic Vibrios are beneficial for controlling and prevention planning of the infectious diseases. This research was carried out to identify the distribution of the recognized pathogenic Vibrios with emphasizing on identification of Vibrio cholera in the wastewater of Kermanshah city western Iran in 2002. The method of study was cr...

  6. Interactions between the microbiota and pathogenic bacteria in the gut

    OpenAIRE

    Bäumler, Andreas J.; Sperandio, Vanessa

    2016-01-01

    The microbiome has an important role in human health. Changes in the microbiota can confer resistance to or promote infection by pathogenic bacteria. Antibiotics have a profound impact on the microbiota that alters the nutritional landscape of the gut and can lead to the expansion of pathogenic populations. Pathogenic bacteria exploit microbiota-derived sources of carbon and nitrogen as nutrients and regulatory signals to promote their own growth and virulence. By eliciting inflammation, thes...

  7. Bacterial pathogen manipulation of host membrane trafficking.

    Science.gov (United States)

    Asrat, Seblewongel; de Jesús, Dennise A; Hempstead, Andrew D; Ramabhadran, Vinay; Isberg, Ralph R

    2014-01-01

    Pathogens use a vast number of strategies to alter host membrane dynamics. Targeting the host membrane machinery is important for the survival and pathogenesis of several extracellular, vacuolar, and cytosolic bacteria. Membrane manipulation promotes bacterial replication while suppressing host responses, allowing the bacterium to thrive in a hostile environment. This review provides a comprehensive summary of various strategies used by both extracellular and intracellular bacteria to hijack host membrane trafficking machinery. We start with mechanisms used by bacteria to alter the plasma membrane, delve into the hijacking of various vesicle trafficking pathways, and conclude by summarizing bacterial adaptation to host immune responses. Understanding bacterial manipulation of host membrane trafficking provides insights into bacterial pathogenesis and uncovers the molecular mechanisms behind various processes within a eukaryotic cell.

  8. Shellfish as reservoirs of bacterial pathogens

    Directory of Open Access Journals (Sweden)

    Harry Hariharan

    2016-04-01

    Full Text Available The objective of this article is to present an overview on bacterial pathogens associated with shellfish in Grenada and other countries including the authors’ experience. Although there have been considerable published work on vibrios, there is a lack of information on Salmonella serovars associated with various shellfish. In Grenada, for instance the blue land crabs collected from their habitats were found to harbor several Salmonella serovars. Also, it is notable that only minimal research has been done on shellfish such as conchs and whelks, which are common in the Caribbean and West Indies. Information on anaerobic bacteria, particularly, non-spore forming bacteria associated with shellfish, in general, is also scanty. This review re-examines this globally important topic based on the recent findings as well as past observations. Strategies for reduction of bacteria in oysters are briefly mentioned because of the fact that oysters are consumed commonly without complete cooking.

  9. Pathogen Security-Help or Hindrance?

    Directory of Open Access Journals (Sweden)

    Stephen Allen Morse

    2015-01-01

    Full Text Available Events over the past 15 years have resulted in the promulgation of regulations in the United States to enhance biosecurity by restricting the access of pathogens and toxins (i.e., biological select agents and toxins [BSAT], which pose a severe threat to human, animal or plant health or to animal or plant products, to qualified institutions, laboratories, and scientists. These regulations also reduce biosafety concerns by imposing specific requirements on laboratories working with BSATs. Furthermore, they provide a legal framework for prosecuting someone who possesses a BSAT illegally. With the implementation of these regulations has come a discussion in the scientific community about the potential of these regulations to affect the cost of doing BSAT research and international collaborations, or whether it would stop someone with a microbiological background from isolating many of the select agents from nature.

  10. Pathogen security-help or hindrance?

    Science.gov (United States)

    Morse, Stephen A

    2014-01-01

    Events over the past 15 years have resulted in the promulgation of regulations in the United States to enhance biosecurity by restricting the access to pathogens and toxins (i.e., biological select agents and toxins [BSATs]), which pose a severe threat to human being, animal, or plant health or to animal or plant products, to qualified institutions, laboratories, and scientists. These regulations also reduce biosafety concerns by imposing specific requirements on laboratories working with BSATs. Furthermore, they provide a legal framework for prosecuting someone who possesses a BSAT illegally. With the implementation of these regulations has come discussion in the scientific community about the potential of these regulations to affect the cost of doing BSAT research, hamper research and international collaborations, or whether it would stop someone with a microbiological background from isolating many of the select agents from nature.

  11. The systems biology of host pathogen interactions.

    Directory of Open Access Journals (Sweden)

    Nikolai Petrovsky

    2013-06-01

    Full Text Available Infectious diseases constitute a major public health burden, particularly in developing countries. Amongst the pathogens afflicting humans, malaria, HIV, shigellosis and tuberculosis (TB cause a large number of deaths. Whilst antivirals, antibiotics and antiparasitic drugs have all helped to reduce the burden of disease, problems of drug resistance are increasingly common, presenting the need to come up with alternative approaches to disease prevention. Ideally, effective prophylactic vaccines would be developed against each of these infections, but unfortunately with the exception of TB, no vaccine is currently available against the other three infections. Baring a breakthrough, coming for example from the application of newer more potent adjuvants to vaccine candidates, new paradigms are needed to help tackle these infectious diseases.

  12. Pathogen detection by the polymerase chain reaction

    Energy Technology Data Exchange (ETDEWEB)

    Chitpatima, S T; Settachan, D; Pornsilpatip, J; Visawapoka, U [Pramongkutklao College of Medicine, Bangkok (Thailand). Molecular Biology Lab.; Dvorak, D R [Amersham International Ltd., Singapore (Singapore)

    1994-05-01

    In recent years, significant advances in the knowledge of DNA and its make up have led to the development of a powerful technique called polymerase chain reaction (PCR). Since the advent of PCR, laboratories around the globe have been exploiting this technology to bridge limitations or to overcome common problems encountered in molecular biology techniques. In addition, this technology has been employed successfully in diagnostic and basic scientific research and development. The true potentials of this technology is realized in early detection of pathogens and genetic abnormalities. In this paper two PCR protocols are described. The first is for detection of HIV-1 DNA in blood, the other for detection of rabies virus RNA in brain cells. 6 refs, 3 figs, 1 tab.

  13. Bacterial toxins as pathogen weapons against phagocytes

    Directory of Open Access Journals (Sweden)

    Ana edo Vale

    2016-02-01

    Full Text Available Bacterial toxins are virulence factors that manipulate host cell functions and take over the control of vital processes of living organisms to favour microbial infection. Some toxins directly target innate immune cells, thereby annihilating a major branch of the host immune response. In this review we will focus on bacterial toxins that act from the extracellular milieu and hinder the function of macrophages and neutrophils. In particular, we will concentrate on toxins from Gram-positive and Gram-negative bacteria that manipulate cell signalling or induce cell death by either imposing direct damage to the host cells cytoplasmic membrane or enzymatically modifying key eukaryotic targets. Outcomes regarding pathogen dissemination, host damage and disease progression will be discussed.

  14. Porphyromonas gingivalis: Major Periodontopathic Pathogen Overview

    Science.gov (United States)

    Mysak, Jaroslav; Podzimek, Stepan; Sommerova, Pavla; Lyuya-Mi, Yelena; Bartova, Jirina; Janatova, Tatjana; Prochazkova, Jarmila; Duskova, Jana

    2014-01-01

    Porphyromonas gingivalis is a Gram-negative oral anaerobe that is involved in the pathogenesis of periodontitis and is a member of more than 500 bacterial species that live in the oral cavity. This anaerobic bacterium is a natural member of the oral microbiome, yet it can become highly destructive (termed pathobiont) and proliferate to high cell numbers in periodontal lesions: this is attributed to its arsenal of specialized virulence factors. The purpose of this review is to provide an overview of one of the main periodontal pathogens—Porphyromonas gingivalis. This bacterium, along with Treponema denticola and Tannerella forsythia, constitute the “red complex,” a prototype polybacterial pathogenic consortium in periodontitis. This review outlines Porphyromonas gingivalis structure, its metabolism, its ability to colonize the epithelial cells, and its influence upon the host immunity. PMID:24741603

  15. Porphyromonas gingivalis: Major Periodontopathic Pathogen Overview

    Directory of Open Access Journals (Sweden)

    Jaroslav Mysak

    2014-01-01

    Full Text Available Porphyromonas gingivalis is a Gram-negative oral anaerobe that is involved in the pathogenesis of periodontitis and is a member of more than 500 bacterial species that live in the oral cavity. This anaerobic bacterium is a natural member of the oral microbiome, yet it can become highly destructive (termed pathobiont and proliferate to high cell numbers in periodontal lesions: this is attributed to its arsenal of specialized virulence factors. The purpose of this review is to provide an overview of one of the main periodontal pathogens—Porphyromonas gingivalis. This bacterium, along with Treponema denticola and Tannerella forsythia, constitute the “red complex,” a prototype polybacterial pathogenic consortium in periodontitis. This review outlines Porphyromonas gingivalis structure, its metabolism, its ability to colonize the epithelial cells, and its influence upon the host immunity.

  16. Microbial and viral pathogens in colorectal cancer.

    LENUS (Irish Health Repository)

    Collins, Danielle

    2011-05-01

    The heterogenetic and sporadic nature of colorectal cancer has led to many epidemiological associations with causes of this disease. As our understanding of the underlying molecular processes in colorectal-cancer develops, the concept of microbial-epithelial interactions as an oncogenic trigger might provide a plausible hypothesis for the pathogenesis of colorectal cancer. By contrast with other cancers of the gastrointestinal tract (gastric carcinoma, mucosa-associated lymphoid-tissue lymphoma), a direct causal link between microbial infection (bacteria and viruses) and colorectal carcinoma has not been established. Studies support the involvement of these organisms in oncogenesis, however, in colorectal cancer, clinical data are lacking. Here, we discuss current evidence (both in vitro and clinical studies), and focus on a putative role for bacterial and viral pathogens as a cause of colorectal cancer.

  17. Microbial and viral pathogens in colorectal cancer.

    LENUS (Irish Health Repository)

    Collins, Danielle

    2012-02-01

    The heterogenetic and sporadic nature of colorectal cancer has led to many epidemiological associations with causes of this disease. As our understanding of the underlying molecular processes in colorectal-cancer develops, the concept of microbial-epithelial interactions as an oncogenic trigger might provide a plausible hypothesis for the pathogenesis of colorectal cancer. By contrast with other cancers of the gastrointestinal tract (gastric carcinoma, mucosa-associated lymphoid-tissue lymphoma), a direct causal link between microbial infection (bacteria and viruses) and colorectal carcinoma has not been established. Studies support the involvement of these organisms in oncogenesis, however, in colorectal cancer, clinical data are lacking. Here, we discuss current evidence (both in vitro and clinical studies), and focus on a putative role for bacterial and viral pathogens as a cause of colorectal cancer.

  18. WHEAT PATHOGEN RESISTANCE AND CHITINASE PROFILE

    Directory of Open Access Journals (Sweden)

    Zuzana Gregorová

    2015-02-01

    Full Text Available The powdery mildew and leaf rust caused by Blumeria graminis and Puccinia recondita (respectively are common diseases of wheat throughout the world. These fungal diseases greatly affect crop productivity. Incorporation of effective and durable disease resistance is an important breeding objective for wheat improvement. We have evaluated resistance of four bread wheat (Triticum aestivum and four spelt wheat (Triticum spelta cultivars. Chitinases occurrence as well as their activity was determined in leaf tissues. There was no correlation between resistance rating and activity of chitinase. The pattern of chitinases reveals four isoforms with different size in eight wheat cultivars. A detailed understanding of the molecular events that take place during a plant–pathogen interaction is an essential goal for disease control in the future.

  19. Antiadhesion agents against Gram-positive pathogens.

    Science.gov (United States)

    Cascioferro, Stella; Cusimano, Maria Grazia; Schillaci, Domenico

    2014-01-01

    A fundamental step of Gram-positive pathogenesis is the bacterial adhesion to the host tissue involving interaction between bacterial surface molecules and host ligands. This review is focused on antivirulence compounds that target Gram-positive adhesins and on their potential development as therapeutic agents alternative or complementary to conventional antibiotics in the contrast of pathogens. In particular, compounds that target the sortase A, wall theicoic acid inhibitors, carbohydrates able to bind bacterial proteins and proteins capable of influencing the bacterial adhesion, were described. We further discuss the advantages and disadvantages of this strategy in the development of novel antimicrobials and the future perspective of this research field still at its first steps.

  20. Monitoring pathogens from irradiated agriculture products

    International Nuclear Information System (INIS)

    Butterweck, J.S.

    1990-01-01

    The final food and environmental safety assessment of agriculture product irradiation can only be determined by product history. Product history will be used for future research and development, regulations, commercial practices and implementation of agriculture and food irradiation on a regional basis. The commercial irradiator treats large varieties and amounts of products that are used in various environments. it, in time, will generate a large data base of product history. Field product monitoring begins when food irradiation progresses from the pilot/demonstration phase to the commercial phase. At that time, it is important that there be in place a monitoring system to collect and analyze field data. The systems managers, public health authorities and exotic disease specialists will use this information to assess the reduction of food pathogens on the populace and the environment. (author)

  1. Water Microbiology. Bacterial Pathogens and Water

    Directory of Open Access Journals (Sweden)

    João P. S. Cabral

    2010-10-01

    Full Text Available Water is essential to life, but many people do not have access to clean and safe drinking water and many die of waterborne bacterial infections. In this review a general characterization of the most important bacterial diseases transmitted through water—cholera, typhoid fever and bacillary dysentery—is presented, focusing on the biology and ecology of the causal agents and on the diseases’ characteristics and their life cycles in the environment. The importance of pathogenic Escherichia coli strains and emerging pathogens in drinking water-transmitted diseases is also briefly discussed. Microbiological water analysis is mainly based on the concept of fecal indicator bacteria. The main bacteria present in human and animal feces (focusing on their behavior in their hosts and in the environment and the most important fecal indicator bacteria are presented and discussed (focusing on the advantages and limitations of their use as markers. Important sources of bacterial fecal pollution of environmental waters are also briefly indicated. In the last topic it is discussed which indicators of fecal pollution should be used in current drinking water microbiological analysis. It was concluded that safe drinking water for all is one of the major challenges of the 21st century and that microbiological control of drinking water should be the norm everywhere. Routine basic microbiological analysis of drinking water should be carried out by assaying the presence of Escherichia coli by culture methods. Whenever financial resources are available, fecal coliform determinations should be complemented with the quantification of enterococci. More studies are needed in order to check if ammonia is reliable for a preliminary screening for emergency fecal pollution outbreaks. Financial resources should be devoted to a better understanding of the ecology and behavior of human and animal fecal bacteria in environmental waters.

  2. Water microbiology. Bacterial pathogens and water.

    Science.gov (United States)

    Cabral, João P S

    2010-10-01

    Water is essential to life, but many people do not have access to clean and safe drinking water and many die of waterborne bacterial infections. In this review a general characterization of the most important bacterial diseases transmitted through water-cholera, typhoid fever and bacillary dysentery-is presented, focusing on the biology and ecology of the causal agents and on the diseases' characteristics and their life cycles in the environment. The importance of pathogenic Escherichia coli strains and emerging pathogens in drinking water-transmitted diseases is also briefly discussed. Microbiological water analysis is mainly based on the concept of fecal indicator bacteria. The main bacteria present in human and animal feces (focusing on their behavior in their hosts and in the environment) and the most important fecal indicator bacteria are presented and discussed (focusing on the advantages and limitations of their use as markers). Important sources of bacterial fecal pollution of environmental waters are also briefly indicated. In the last topic it is discussed which indicators of fecal pollution should be used in current drinking water microbiological analysis. It was concluded that safe drinking water for all is one of the major challenges of the 21st century and that microbiological control of drinking water should be the norm everywhere. Routine basic microbiological analysis of drinking water should be carried out by assaying the presence of Escherichia coli by culture methods. Whenever financial resources are available, fecal coliform determinations should be complemented with the quantification of enterococci. More studies are needed in order to check if ammonia is reliable for a preliminary screening for emergency fecal pollution outbreaks. Financial resources should be devoted to a better understanding of the ecology and behavior of human and animal fecal bacteria in environmental waters.

  3. Pathogenicity of Salmonella Paratyphi A in Pullets

    Directory of Open Access Journals (Sweden)

    A. O. Ogunleye

    2006-01-01

    Full Text Available The pathogenicity of Salmonella Paratyphi A isolated at Debiwise Poultry Farm during a fulminating outbreak was tested. Twenty 16-week-old pullets were inoculated orally with 0.5 ml of 1.3 x 108 CFU/bird Salmonella Paratyphi A, while 20 others of the same age served as uninfected control. By the fourth day postinoculation (p.i. dullness, ruffled and unkempt feathers, somnolence, yellowish- green diarrhea, decreased water and feed consumption were observed in the infected birds; mortality was 95% by day 16 p.i. Remarkable pathological lesions were recorded between days 7 and 14 p.i. The liver was moderately enlarged, with multiple necrotic foci, and dark brown to bronze coloration. The kidneys were swollen, with widespread focal pale necrotic areas, while the spleen was slightly enlarged. Histopathologically, the proventriculus showed focal glandular necrosis, mononuclear cell infiltration and moderate perivascular leucocytic infiltration. There was mucosal hemorrhage, matting of intestinal villi with reduction of villous height and presence of epithelial debris in the lumen with increased leucocytic infiltration in the lamina propriae. The liver showed moderate, diffuse congestion of the sinusoid and central veins, as well as multiple foci of necrosis of hepatocytes, mononuclear infiltration and perivascular cellular infiltration. There was diffuse lymphoid depletion in the nodule and around the splenic arterioles as well as throughout the parenchyma. The kidneys were congested with tubular epithelial necrosis characterized by karyorrhexis of the nuclei. The organism was recovered from the liver, spleen, heart, heart blood and bone marrow of infected birds. No clinical sign or gross lesion or pathogen was observed in the negative control.

  4. Human milk glycoconjugates that inhibit pathogens.

    Science.gov (United States)

    Newburg, D S

    1999-02-01

    Breast-fed infants have lower incidence of diarrhea, respiratory disease, and otitis media. The protection by human milk has long been attributed to the presence of secretory IgA. However, human milk contains large numbers and amounts of complex carbohydrates, including glycoproteins, glycolipids, glycosaminoglycans, mucins, and especially oligosaccharides. The oligosaccharides comprise the third most abundant solid constituent of human milk, and contain a myriad of structures. Complex carbohydrate moieties of glycoconjugates and oligosaccharides are synthesized by the many glycosyltransferases in the mammary gland; those with homology to cell surface glycoconjugate pathogen receptors may inhibit pathogen binding, thereby protecting the nursing infant. Several examples are reviewed: A fucosyloligosaccharide inhibits the diarrheagenic effect of stable toxin of Escherichia coli. A different fucosyloligosaccharide inhibits infection by Campylobacter jejuni. Binding of Streptococcus pneumoniae and of enteropathogenic E. coli to their respective receptors is inhibited by human milk oligosaccharides. The 46-kD glycoprotein, lactadherin, inhibits rotavirus binding and infectivity. Low levels of lactadherin in human milk are associated with a higher incidence of symptomatic rotavirus in breast-fed infants. A mannosylated glycopeptide inhibits binding by enterohemorrhagic E. coli. A glycosaminoglycan inhibits binding of gp120 to CD4, the first step in HIV infection. Human milk mucin inhibits binding by S-fimbriated E. coli. The ganglioside, GM1, reduces diarrhea production by cholera toxin and labile toxin of E. coli. The neutral glycosphingolipid, Gb3, binds to Shigatoxin. Thus, many complex carbohydrates of human milk may be novel antipathogenic agents, and the milk glycoconjugates and oligosaccharides may be a major source of protection for breastfeeding infants.

  5. Viruses, Other Pathogenic Microorganisms and Esophageal Cancer.

    Science.gov (United States)

    Xu, Wenji; Liu, Zhongshu; Bao, Quncha; Qian, Zhikan

    2015-05-01

    Esophageal cancer (EC) is the eighth most prevalent malignant tumor and the sixth leading cause of cancer mortality throughout the world. Despite the technical developments in diagnosis and treatment, the 5-year survival rate is still low. The etiology of EC remains poorly understood; multiple risk factors may be involved and account for the great variation in EC incidence in different geographic regions. Infection with carcinogenetic pathogens has been proposed as a risk factor for EC. This review explores the recent studies on the association of human papillomavirus (HPV), Epstein-Barr virus (EBV), Helicobacter pylori and esophageal bacterial biota with EC. Among the above-mentioned pathogens, HPV most likely contributes to esophageal squamous cell carcinoma (ESCC) in high-risk populations. New techniques are being applied to studies on the role of infection in EC, which will inevitably bring novel ideas to the field in the near future. Multiple meta-analyses support the finding of a higher HPV detection rate in regions associated with high risk for ESCC compared to low-risk areas. A potential role of HPV in the rise of esophageal adenocarcinoma (EAC) was proposed recently. However, further studies are required before a firm conclusion can be drawn. Less work has been done in studying the association between EBV and ESCC, and the results are quite controversial. H. pylori infection is found to be inversely related to EC, which is probably due to the reduced incidence of gastroesophageal reflux disease. Analysis of the esophageal bacterial biota revealed distinct clusters of bacteria in normal and diseased esophagi. A type II microbiome rich in Gram-negative bacteria potentially contributes to EAC by inducing chronic inflammation. Novel findings from such studies as these may benefit public health by justifying anti-infection measures to prevent EC.

  6. Molecular Diagnosis of Pathogenic Sporothrix Species.

    Directory of Open Access Journals (Sweden)

    Anderson Messias Rodrigues

    2015-12-01

    Full Text Available Sporotrichosis is a chronic (subcutaneous infection caused by thermodimorphic fungi in the order, Ophiostomatales. These fungi are characterized by major differences in routes of transmission, host predilections, species virulence, and susceptibilities to antifungals. Sporothrix species emerge in the form of outbreaks. Large zoonoses and sapronoses are ongoing in Brazil and China, respectively. Current diagnostic methods based on morphology and physiology are inaccurate due to closely related phenotypes with overlapping components between pathogenic and non-pathogenic Sporothrix. There is a critical need for new diagnostic tools that are specific, sensitive, and cost-effective.We developed a panel of novel markers, based on calmodulin (CAL gene sequences, for the large-scale diagnosis and epidemiology of clinically relevant members of the Sporothrix genus, and its relative, Ophiostoma. We identified specific PCR-based markers for S. brasiliensis, S. schenckii, S. globosa, S. mexicana, S. pallida, and O. stenoceras. We employed a murine model of disseminated sporotrichosis to optimize a PCR assay for detecting Sporothrix in clinical specimens.Primer-BLAST searches revealed candidate sequences that were conserved within a single species. Species-specific primers showed no significant homology with human, mouse, or microorganisms outside the Sporothrix genus. The detection limit was 10-100 fg of DNA in a single round of PCR for identifying S. brasiliensis, S. schenckii, S. globosa, S. mexicana, and S. pallida. A simple, direct PCR assay, with conidia as a source of DNA, was effective for rapid, low-cost genotyping. Samples from a murine model of disseminated sporotrichosis confirmed the feasibility of detecting S. brasiliensis and S. schenckii DNA in spleen, liver, lungs, heart, brain, kidney, tail, and feces of infected animals.This PCR-based method could successfully detect and identify a single species in samples from cultures and from clinical

  7. Molecular Diagnosis of Pathogenic Sporothrix Species

    Science.gov (United States)

    Rodrigues, Anderson Messias; de Hoog, G. Sybren; de Camargo, Zoilo Pires

    2015-01-01

    Background Sporotrichosis is a chronic (sub)cutaneous infection caused by thermodimorphic fungi in the order, Ophiostomatales. These fungi are characterized by major differences in routes of transmission, host predilections, species virulence, and susceptibilities to antifungals. Sporothrix species emerge in the form of outbreaks. Large zoonoses and sapronoses are ongoing in Brazil and China, respectively. Current diagnostic methods based on morphology and physiology are inaccurate due to closely related phenotypes with overlapping components between pathogenic and non-pathogenic Sporothrix. There is a critical need for new diagnostic tools that are specific, sensitive, and cost-effective. Methodology We developed a panel of novel markers, based on calmodulin (CAL) gene sequences, for the large-scale diagnosis and epidemiology of clinically relevant members of the Sporothrix genus, and its relative, Ophiostoma. We identified specific PCR-based markers for S. brasiliensis, S. schenckii, S. globosa, S. mexicana, S. pallida, and O. stenoceras. We employed a murine model of disseminated sporotrichosis to optimize a PCR assay for detecting Sporothrix in clinical specimens. Results Primer-BLAST searches revealed candidate sequences that were conserved within a single species. Species-specific primers showed no significant homology with human, mouse, or microorganisms outside the Sporothrix genus. The detection limit was 10–100 fg of DNA in a single round of PCR for identifying S. brasiliensis, S. schenckii, S. globosa, S. mexicana, and S. pallida. A simple, direct PCR assay, with conidia as a source of DNA, was effective for rapid, low-cost genotyping. Samples from a murine model of disseminated sporotrichosis confirmed the feasibility of detecting S. brasiliensis and S. schenckii DNA in spleen, liver, lungs, heart, brain, kidney, tail, and feces of infected animals. Conclusions This PCR-based method could successfully detect and identify a single species in samples

  8. Investigating Ebola virus pathogenicity using molecular dynamics.

    Science.gov (United States)

    Pappalardo, Morena; Collu, Francesca; Macpherson, James; Michaelis, Martin; Fraternali, Franca; Wass, Mark N

    2017-08-11

    Ebolaviruses have been known to cause deadly disease in humans for 40 years and have recently been demonstrated in West Africa to be able to cause large outbreaks. Four Ebolavirus species cause severe disease associated with high mortality in humans. Reston viruses are the only Ebolaviruses that do not cause disease in humans. Conserved amino acid changes in the Reston virus protein VP24 compared to VP24 of other Ebolaviruses have been suggested to alter VP24 binding to host cell karyopherins resulting in impaired inhibition of interferon signalling, which may explain the difference in human pathogenicity. Here we used protein structural analysis and molecular dynamics to further elucidate the interaction between VP24 and KPNA5. As a control experiment, we compared the interaction of wild-type and R137A-mutant (known to affect KPNA5 binding) Ebola virus VP24 with KPNA5. Results confirmed that the R137A mutation weakens direct VP24-KPNA5 binding and enables water molecules to penetrate at the interface. Similarly, Reston virus VP24 displayed a weaker interaction with KPNA5 than Ebola virus VP24, which is likely to reduce the ability of Reston virus VP24 to prevent host cell interferon signalling. Our results provide novel molecular detail on the interaction of Reston virus VP24 and Ebola virus VP24 with human KPNA5. The results indicate a weaker interaction of Reston virus VP24 with KPNA5 than Ebola virus VP24, which is probably associated with a decreased ability to interfere with the host cell interferon response. Hence, our study provides further evidence that VP24 is a key player in determining Ebolavirus pathogenicity.

  9. Reduction of quaternary ammonium-induced ocular surface toxicity by emulsions: an in vivo study in rabbits.

    Science.gov (United States)

    Liang, H; Brignole-Baudouin, F; Rabinovich-Guilatt, L; Mao, Z; Riancho, L; Faure, M O; Warnet, J M; Lambert, G; Baudouin, C

    2008-01-31

    To evaluate and compare the toxicological profiles of two quaternary ammonium compounds (QAC), benzalkonium chloride (BAK), and cetalkonium chloride (CKC), in standard solution or cationic emulsion formulations in rabbit eyes using newly developed in vivo and ex vivo experimental approaches. Seventy eyes of 35 adult male New Zealand albino rabbits were used in this study. They were randomly divided into five groups: 50 microl of phosphate-buffered saline (PBS), PBS containing 0.02% BAK or 0.002% CKC (BAK Sol and CKC Sol, respectively), and emulsion containing 0.02% BAK or 0.002% CKC (BAK Em and CKC Em, respectively) were applied to rabbit eyes 15 times at 5-min intervals. The ocular surface changes induced by these eye drops were investigated using slit-lamp examination, flow cytometry (FCM), impression cytology (IC) on conjunctiva, and corneal in vivo confocal microscopy (IVCM). Standard immunohistology in cryosections was also examined for cluster of differentiation (CD) 45+ infiltrating and terminal deoxynucleotidyl transferase-mediated dUTP-nick end labeling (TUNEL)+ apoptotic cells. Clinical observations and IVCM showed that the highest toxicity was induced by BAK Sol, characterized by damaged corneal epithelium and a high level of inflammatory infiltration. BAK Em and CKC Sol presented moderate effects, and CKC Em showed the lowest toxicity with results similar to those of PBS. Conjunctival imprints analyzed by FCM showed a higher expression of RLA-DR and TNFR1 markers in BAK Sol-instilled eyes than in all other groups, especially at 4 h. Immunohistology was correlated with in vivo and ex vivo findings and confirmed this toxicity profile. A high level of infiltration of CD45+ inflammatory cells and TUNEL+ apoptotic cells was observed in limbus and conjunctiva, especially in QAC solution-receiving eyes compared to QAC emulsion-instilled eyes. The acute administration of 15 instillations at 5 min intervals was a rapid and efficient model to assess quaternary ammonium toxicity profiles. This model showed the highest toxicity, induced by the BAK solution, and the lowest level of toxicity, induced by the CKC emulsion. These in vivo and ex vivo experimental approaches demonstrated that ocular surface toxicity was reduced by using an emulsion instead of a traditional solution and that a CKC emulsion was safe for future ocular administration.

  10. Proteomic analysis of Herbaspirillum seropedicae reveals ammonium-induced AmtB-dependent membrane sequestration of PII proteins.

    Science.gov (United States)

    Huergo, Luciano F; Noindorf, Lilian; Gimenes, Camila; Lemgruber, Renato S P; Cordellini, Daniela F; Falarz, Lucas J; Cruz, Leonardo M; Monteiro, Rose A; Pedrosa, Fábio O; Chubatsu, Leda S; Souza, Emanuel M; Steffens, Maria B R

    2010-07-01

    This study was aimed at describing the spectrum and dynamics of proteins associated with the membrane in the nitrogen-fixing bacterium Herbaspirillum seropedicae according to the availability of fixed nitrogen. Using two-dimensional electrophoresis we identified 79 protein spots representing 45 different proteins in the membrane fraction of H. seropedicae. Quantitative analysis of gel images of membrane extracts indicated two spots with increased levels when cells were grown under nitrogen limitation in comparison with nitrogen sufficiency; these spots were identified as the GlnK protein and as a conserved noncytoplasmic protein of unknown function which was encoded in an operon together with GlnK and AmtB. Comparison of gel images of membrane extracts from cells grown under nitrogen limitation or under the same regime but collected after an ammonium shock revealed two proteins, GlnB and GlnK, with increased levels after the shock. The P(II) proteins were not present in the membrane fraction of an amtB mutant. The results reported here suggest that changes in the cellular localization of P(II) might play a role in the control of nitrogen metabolism in H. seropedicae.

  11. Sensitizing pathogens to antibiotics using the CRISPR-Cas system.

    Science.gov (United States)

    Goren, Moran; Yosef, Ido; Qimron, Udi

    2017-01-01

    The extensive use of antibiotics over the last century has resulted in a significant artificial selection pressure for antibiotic-resistant pathogens to evolve. Various strategies to fight these pathogens have been introduced including new antibiotics, naturally-derived enzymes/peptides that specifically target pathogens and bacteriophages that lyse these pathogens. A new tool has recently been introduced in the fight against drug-resistant pathogens-the prokaryotic defense mechanism-clustered regularly interspaced short palindromic repeats-CRISPR associated (CRISPR-Cas) system. The CRISPR-Cas system acts as a nuclease that can be guided to cleave any target DNA, allowing sophisticated, yet feasible, manipulations of pathogens. Here, we review pioneering studies that use the CRISPR-Cas system to specifically edit bacterial populations, eliminate their resistance genes and combine these two strategies in order to produce an artificial selection pressure for antibiotic-sensitive pathogens. We suggest that intelligent design of this system, along with efficient delivery tools into pathogens, may significantly reduce the threat of antibiotic-resistant pathogens. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Multiplex detection of plant pathogens using a microsphere immunoassay technology.

    Directory of Open Access Journals (Sweden)

    Ratthaphol Charlermroj

    Full Text Available Plant pathogens are a serious problem for seed export, plant disease control and plant quarantine. Rapid and accurate screening tests are urgently required to protect and prevent plant diseases spreading worldwide. A novel multiplex detection method was developed based on microsphere immunoassays to simultaneously detect four important plant pathogens: a fruit blotch bacterium Acidovorax avenae subsp. citrulli (Aac, chilli vein-banding mottle virus (CVbMV, potyvirus, watermelon silver mottle virus (WSMoV, tospovirus serogroup IV and melon yellow spot virus (MYSV, tospovirus. An antibody for each plant pathogen was linked on a fluorescence-coded magnetic microsphere set which was used to capture corresponding pathogen. The presence of pathogens was detected by R-phycoerythrin (RPE-labeled antibodies specific to the pathogens. The assay conditions were optimized by identifying appropriate antibody pairs, blocking buffer, concentration of RPE-labeled antibodies and assay time. Once conditions were optimized, the assay was able to detect all four plant pathogens precisely and accurately with substantially higher sensitivity than enzyme-linked immunosorbent assay (ELISA when spiked in buffer and in healthy watermelon leaf extract. The assay time of the microsphere immunoassay (1 hour was much shorter than that of ELISA (4 hours. This system was also shown to be capable of detecting the pathogens in naturally infected plant samples and is a major advancement in plant pathogen detection.

  13. Multiplex detection of plant pathogens using a microsphere immunoassay technology.

    Science.gov (United States)

    Charlermroj, Ratthaphol; Himananto, Orawan; Seepiban, Channarong; Kumpoosiri, Mallika; Warin, Nuchnard; Oplatowska, Michalina; Gajanandana, Oraprapai; Grant, Irene R; Karoonuthaisiri, Nitsara; Elliott, Christopher T

    2013-01-01

    Plant pathogens are a serious problem for seed export, plant disease control and plant quarantine. Rapid and accurate screening tests are urgently required to protect and prevent plant diseases spreading worldwide. A novel multiplex detection method was developed based on microsphere immunoassays to simultaneously detect four important plant pathogens: a fruit blotch bacterium Acidovorax avenae subsp. citrulli (Aac), chilli vein-banding mottle virus (CVbMV, potyvirus), watermelon silver mottle virus (WSMoV, tospovirus serogroup IV) and melon yellow spot virus (MYSV, tospovirus). An antibody for each plant pathogen was linked on a fluorescence-coded magnetic microsphere set which was used to capture corresponding pathogen. The presence of pathogens was detected by R-phycoerythrin (RPE)-labeled antibodies specific to the pathogens. The assay conditions were optimized by identifying appropriate antibody pairs, blocking buffer, concentration of RPE-labeled antibodies and assay time. Once conditions were optimized, the assay was able to detect all four plant pathogens precisely and accurately with substantially higher sensitivity than enzyme-linked immunosorbent assay (ELISA) when spiked in buffer and in healthy watermelon leaf extract. The assay time of the microsphere immunoassay (1 hour) was much shorter than that of ELISA (4 hours). This system was also shown to be capable of detecting the pathogens in naturally infected plant samples and is a major advancement in plant pathogen detection.

  14. The role of social cognition in parasite and pathogen avoidance.

    Science.gov (United States)

    Kavaliers, Martin; Choleris, Elena

    2018-07-19

    The acquisition and use of social information are integral to social behaviour and parasite/pathogen avoidance. This involves social cognition which encompasses mechanisms for acquiring, processing, retaining and acting on social information. Social cognition entails the acquisition of social information about others (i.e. social recognition) and from others (i.e. social learning). Social cognition involves assessing other individuals and their infection status and the pathogen and parasite threat they pose and deciding about when and how to interact with them. Social cognition provides a framework for examining pathogen and parasite avoidance behaviours and their associated neurobiological mechanisms. Here, we briefly consider the relationships between social cognition and olfactory-mediated pathogen and parasite avoidance behaviours. We briefly discuss aspects of (i) social recognition of actual and potentially infected individuals and the impact of parasite/pathogen threat on mate and social partner choice; (ii) the roles of 'out-groups' (strangers, unfamiliar individuals) and 'in-groups' (familiar individuals) in the expression of parasite/pathogen avoidance behaviours; (iii) individual and social learning, i.e. the utilization of the pathogen recognition and avoidance responses of others; and (iv) the neurobiological mechanisms, in particular the roles of the nonapeptide, oxytocin and steroid hormones (oestrogens) associated with social cognition and parasite/pathogen avoidance.This article is part of the Theo Murphy meeting issue 'Evolution of pathogen and parasite avoidance behaviours'. © 2018 The Author(s).

  15. Models of Caenorhabditis elegans infection by bacterial and fungal pathogens.

    Science.gov (United States)

    Powell, Jennifer R; Ausubel, Frederick M

    2008-01-01

    The nematode Caenorhabditis elegans is a simple model host for studying the relationship between the animal innate immune system and a variety of bacterial and fungal pathogens. Extensive genetic and molecular tools are available in C. elegans, facilitating an in-depth analysis of host defense factors and pathogen virulence factors. Many of these factors are conserved in insects and mammals, indicating the relevance of the nematode model to the vertebrate innate immune response. Here, we describe pathogen assays for a selection of the most commonly studied bacterial and fungal pathogens using the C. elegans model system.

  16. Genetic changes that accompanied shifts of low pathogenic avian influenza viruses toward higher pathogenicity in poultry

    Science.gov (United States)

    Abdelwhab, El-Sayed M; Veits, Jutta; Mettenleiter, Thomas C

    2013-01-01

    Avian influenza viruses (AIV) of H5 and H7 subtypes exhibit two different pathotypes in poultry: infection with low pathogenic (LP) strains results in minimal, if any, health disturbances, whereas highly pathogenic (HP) strains cause severe morbidity and mortality. LPAIV of H5 and H7 subtypes can spontaneously mutate into HPAIV. Ten outbreaks caused by HPAIV are known to have been preceded by circulation of a predecessor LPAIV in poultry. Three of them were caused by H5N2 subtype and seven involved H7 subtype in combination with N1, N3, or N7. Here, we review those outbreaks and summarize the genetic changes which resulted in the transformation of LPAIV to HPAIV under natural conditions. Mutations that were found directly in those outbreaks are more likely to be linked to virulence, pathogenesis, and early adaptation of AIV. PMID:23863606

  17. The Quantitative Basis of the Arabidopsis Innate Immune System to Endemic Pathogens Depends on Pathogen Genetics.

    Directory of Open Access Journals (Sweden)

    Jason A Corwin

    2016-02-01

    Full Text Available The most established model of the eukaryotic innate immune system is derived from examples of large effect monogenic quantitative resistance to pathogens. However, many host-pathogen interactions involve many genes of small to medium effect and exhibit quantitative resistance. We used the Arabidopsis-Botrytis pathosystem to explore the quantitative genetic architecture underlying host innate immune system in a population of Arabidopsis thaliana. By infecting a diverse panel of Arabidopsis accessions with four phenotypically and genotypically distinct isolates of the fungal necrotroph B. cinerea, we identified a total of 2,982 genes associated with quantitative resistance using lesion area and 3,354 genes associated with camalexin production as measures of the interaction. Most genes were associated with resistance to a specific Botrytis isolate, which demonstrates the influence of pathogen genetic variation in analyzing host quantitative resistance. While known resistance genes, such as receptor-like kinases (RLKs and nucleotide-binding site leucine-rich repeat proteins (NLRs, were found to be enriched among associated genes, they only account for a small fraction of the total genes associated with quantitative resistance. Using publically available co-expression data, we condensed the quantitative resistance associated genes into co-expressed gene networks. GO analysis of these networks implicated several biological processes commonly connected to disease resistance, including defense hormone signaling and ROS production, as well as novel processes, such as leaf development. Validation of single gene T-DNA knockouts in a Col-0 background demonstrate a high success rate (60% when accounting for differences in environmental and Botrytis genetic variation. This study shows that the genetic architecture underlying host innate immune system is extremely complex and is likely able to sense and respond to differential virulence among pathogen

  18. Comparative genomics and the evolution of pathogenicity in human pathogenic fungi.

    LENUS (Irish Health Repository)

    Moran, Gary P

    2011-01-01

    Because most fungi have evolved to be free-living in the environment and because the infections they cause are usually opportunistic in nature, it is often difficult to identify specific traits that contribute to fungal pathogenesis. In recent years, there has been a surge in the number of sequenced genomes of human fungal pathogens, and comparison of these sequences has proved to be an excellent resource for exploring commonalities and differences in how these species interact with their hosts. In order to survive in the human body, fungi must be able to adapt to new nutrient sources and environmental stresses. Therefore, genes involved in carbohydrate and amino acid metabolism and transport and genes encoding secondary metabolites tend to be overrepresented in pathogenic species (e.g., Aspergillus fumigatus). However, it is clear that human commensal yeast species such as Candida albicans have also evolved a range of specific factors that facilitate direct interaction with host tissues. The evolution of virulence across the human pathogenic fungi has occurred largely through very similar mechanisms. One of the most important mechanisms is gene duplication and the expansion of gene families, particularly in subtelomeric regions. Unlike the case for prokaryotic pathogens, horizontal transfer of genes between species and other genera does not seem to have played a significant role in the evolution of fungal virulence. New sequencing technologies promise the prospect of even greater numbers of genome sequences, facilitating the sequencing of multiple genomes and transcriptomes within individual species, and will undoubtedly contribute to a deeper insight into fungal pathogenesis.

  19. Modeling the intracellular pathogen-immune interaction with cure rate

    Science.gov (United States)

    Dubey, Balram; Dubey, Preeti; Dubey, Uma S.

    2016-09-01

    Many common and emergent infectious diseases like Influenza, SARS, Hepatitis, Ebola etc. are caused by viral pathogens. These infections can be controlled or prevented by understanding the dynamics of pathogen-immune interaction in vivo. In this paper, interaction of pathogens with uninfected and infected cells in presence or absence of immune response are considered in four different cases. In the first case, the model considers the saturated nonlinear infection rate and linear cure rate without absorption of pathogens into uninfected cells and without immune response. The next model considers the effect of absorption of pathogens into uninfected cells while all other terms are same as in the first case. The third model incorporates innate immune response, humoral immune response and Cytotoxic T lymphocytes (CTL) mediated immune response with cure rate and without absorption of pathogens into uninfected cells. The last model is an extension of the third model in which the effect of absorption of pathogens into uninfected cells has been considered. Positivity and boundedness of solutions are established to ensure the well-posedness of the problem. It has been found that all the four models have two equilibria, namely, pathogen-free equilibrium point and pathogen-present equilibrium point. In each case, stability analysis of each equilibrium point is investigated. Pathogen-free equilibrium is globally asymptotically stable when basic reproduction number is less or equal to unity. This implies that control or prevention of infection is independent of initial concentration of uninfected cells, infected cells, pathogens and immune responses in the body. The proposed models show that introduction of immune response and cure rate strongly affects the stability behavior of the system. Further, on computing basic reproduction number, it has been found to be minimum for the fourth model vis-a-vis other models. The analytical findings of each model have been exemplified by

  20. Pathogen and biological contamination management in plant tissue culture: phytopathogens, vitro pathogens, and vitro pests.

    Science.gov (United States)

    Cassells, Alan C

    2012-01-01

    The ability to establish and grow plant cell, organ, and tissue cultures has been widely exploited for basic and applied research, and for the commercial production of plants (micro-propagation). Regardless of whether the application is for research or commerce, it is essential that the cultures be established in vitro free of biological contamination and be maintained as aseptic cultures during manipulation, growth, and storage. The risks from microbial contamination are spurious experimental results due to the effects of latent contaminants or losses of valuable experimental or commercial cultures. Much of the emphasis in culture contamination management historically focussed on the elimination of phytopathogens and the maintenance of cultures free from laboratory contamination by environmental bacteria, fungi (collectively referred to as "vitro pathogens", i.e. pathogens or environmental micro-organisms which cause culture losses), and micro-arthropods ("vitro pests"). Microbial contamination of plant tissue cultures is due to the high nutrient availability in the almost universally used Murashige and Skoog (Physiol Plant 15:473-497, 1962) basal medium or variants of it. In recent years, it has been shown that many plants, especially perennials, are at least locally endophytically colonized intercellularly by bacteria. The latter, and intracellular pathogenic bacteria and viruses/viroids, may pass latently into culture and be spread horizontally and vertically in cultures. Growth of some potentially cultivable endophytes may be suppressed by the high salt and sugar content of the Murashige and Skoog basal medium and suboptimal temperatures for their growth in plant tissue growth rooms. The management of contamination in tissue culture involves three stages: disease screening (syn. disease indexing) of the stock plants with disease and endophyte elimination where detected; establishment and pathogen and contaminant screening of established initial cultures

  1. Specific recognition of fungal pathogens by plants

    International Nuclear Information System (INIS)

    Knogge, W.; Gierlich, A.; Max-Planck-Institute for Plant Breeding,; Van't Slot, K.A.E.; Papavoine, T.

    2001-01-01

    Full text: Induction of plant defence reactions and, hence, genotype-specific disease resistance results from the interaction of highly specific plant resistance (R) genes with matching pathogen avirulence (Avr) genes (gene-for-gene interactions). More than thirty R genes acting against different types of pathogens (viruses, bacteria, fungi, oomycetes, nematodes) have been isolated from various plants species. However, with few exceptions it remains to be shown how their products recognise the complementary Avr gene products. To date, Avr genes and their products have been characterised from only three fungal species. These include the NIP1 gene from Rhynchosporium secalis, the causal agent of barley leaf scald. It encodes a small, secreted protein, NIP1, that triggers defence reactions exclusively in barley cultivars expressing the R gene Rrs1. NIP1 also non-specifically stimulates the H + -ATPase activity in barley plasma membranes, suggesting that the host recognition system targets a putative fungal virulence factor. Virulent fungal strains lack the gene or carry an allele encoding a non-functional product. Four NIP1 iso-forms have been characterised; NIP1-I and NIP1-II although both elicitor-active display different levels of activity, whereas the isoforms NIP1-III and NIP1-IV are inactive. After establishing a heterologous expression system, the single amino acids specifying NIP1-III and NIP1-IV were integrated into the NIP1-I sequence and yielded the inactive mutant proteins NIP1-III* and NIP1-IV*. The elicitor-inactive isoforms were also unable to stimulate the H + -ATPase, suggesting that both functions of NIP1 are mediated by a single plant receptor. The 3D structure of NIP1-I has been elucidated by 1 H- and 15 N-NMR spectroscopy. Binding studies using 125 I-NIP1-I revealed a single class of high-affinity binding sites on membranes from both Rrs1- and rrs1-cultivars, suggesting that NIP1-binding is not sufficient for defence triggering and that an

  2. USGS highly pathogenic avian influenza research strategy

    Science.gov (United States)

    Harris, M. Camille; Miles, A. Keith; Pearce, John M.; Prosser, Diann J.; Sleeman, Jonathan M.; Whalen, Mary E.

    2015-09-09

    Avian influenza viruses are naturally occurring in wild birds such as ducks, geese, swans, and gulls. These viruses generally do not cause illness in wild birds, however, when spread to poultry they can be highly pathogenic and cause illness and death in backyard and commercial farms. Outbreaks may cause devastating agricultural economic losses and some viral strains have the potential to infect people directly. Furthermore, the combination of avian influenza viruses with mammalian viruses can result in strains with the ability to transmit from person to person, possibly leading to viruses with pandemic potential. All known pandemic influenza viruses have had some genetic material of avian origin. Since 1996, a strain of highly pathogenic avian influenza (HPAI) virus, H5N1, has caused infection in wild birds, losses to poultry farms in Eurasia and North Africa, and led to the deaths of several hundred people. Spread of the H5N1 virus and other influenza strains from China was likely facilitated by migratory birds. In December 2014, HPAI was detected in poultry in Canada and migratory birds in the United States. Since then, HPAI viruses have spread to large parts of the United States and will likely continue to spread through migratory bird flyways and other mechanisms throughout North America. In the United States, HPAI viruses have severely affected the poultry industry with millions of domestic birds dead or culled. These strains of HPAI are not known to cause disease in humans; however, the Centers for Disease Control and Prevention (CDC) advise caution when in close contact with infected birds. Experts agree that HPAI strains currently circulating in wild birds of North America will likely persist for the next few years. This unprecedented situation presents risks to the poultry industry, natural resource management, and potentially human health. Scientific knowledge and decision support tools are urgently needed to understand factors affecting the persistence

  3. Isolation and characterization of pathogenic leptospires associated with cattle

    Science.gov (United States)

    Pathogenic leptospires colonize the renal tubules of reservoir hosts of infection, including cattle, and are excreted via urine. In order to identify circulating serovars of pathogenic leptospires in beef cattle, and their associated rates of urinary excretion, a cross sectional study was performed....

  4. Modelling animal waste pathogen transport from agricultural land to streams

    International Nuclear Information System (INIS)

    Pandey, Pramod K; Soupir, Michelle L; Ikenberry, Charles

    2014-01-01

    The transport of animal waste pathogens from crop land to streams can potentially elevate pathogen levels in stream water. Applying animal manure into crop land as fertilizers is a common practice in developing as well as in developed countries. Manure application into the crop land, however, can cause potential human health. To control pathogen levels in ambient water bodies such as streams, improving our understanding of pathogen transport at farm scale as well as at watershed scale is required. To understand the impacts of crop land receiving animal waste as fertilizers on stream's pathogen levels, here we investigate pathogen indicator transport at watershed scale. We exploited watershed scale hydrological model to estimate the transport of pathogens from the crop land to streams. Pathogen indicator levels (i.e., E. coli levels) in the stream water were predicted. With certain assumptions, model results are reasonable. This study can be used as guidelines for developing the models for calculating the impacts of crop land's animal manure on stream water

  5. Oral cavity anaerobic pathogens in biofilm formation on voice prostheses

    NARCIS (Netherlands)

    Bertl, Kristina; Zijnge, Vincent; Zatorska, Beata; Leonhard, Matthias; Schneider-Stickler, Berit; Harmsen, Hermie J. M.

    BACKGROUND: A polymerase chain reaction (PCR)-based method has been used to identify oral anaerobic pathogens in biofilms on voice prostheses. The purpose of the present study was to determine the location of those pathogens inside the biofilms. METHODS: Biofilms of 15 voice prostheses were sampled

  6. Pathogen-avoidance mechanisms and the stigmatization of obese people

    NARCIS (Netherlands)

    Park, Justin H.; Schaller, Mark; Crandall, Christian S.

    2007-01-01

    Humans possess pathogen-avoidance mechanisms that respond to the visual perception of morphological anomalies in others. We investigated whether obesity may trigger these mechanisms. Study I revealed that people who are chronically concerned about pathogen transmission have more negative attitudes

  7. Disease burden of foodborne pathogens in the Netherlands, 2009

    NARCIS (Netherlands)

    Havelaar, A.H.|info:eu-repo/dai/nl/072306122; Haagsma, J.A.; Mangen, M.J.J.; Kemmeren, J.M.; Verhoef, L.; Vijgen, S.M.; Wilson, M; Friesema, I.H.; Kortbeek, L.M.; van Duynhoven, Y.T.; van Pelt, W.

    2012-01-01

    To inform risk management decisions on control, prevention and surveillance of foodborne disease, the disease burden of foodborne pathogens is estimated using Disability Adjusted Life Years as a summary metric of public health. Fourteen pathogens that can be transmitted by food are included in the

  8. LOW PATHOGENIC POTENTIAL IN HETEROTROPHIC BACTERIA FROM POTABLE WATER

    Science.gov (United States)

    Forty-five isolates of HPC bacteria, most of which express virulence-related characteristics are being tested for pathogenicity in immunocompromised mice. All forty-five were negative for facultative intracellular pathogenicity. All twenty-three isolates tested thus far were a...

  9. Survival of pathogenic Escherichia coli on basil, lettuce, and spinach

    Science.gov (United States)

    The contamination of lettuce, spinach and basil with pathogenic E. coli has caused numerous illnesses over the past decade. E. coli O157:H7, E. coli O104:H4 and avian pathogenic E. coli (APECstx- and APECstx+) were inoculated on basil plants and in promix soiless substrate using drip and overhead ir...

  10. Rapid identification and detection of pathogenic Fungi by padlock probes

    NARCIS (Netherlands)

    Tsui, C.K.M.; Wang, B.; Schoen, C.D.; Hamelin, R.C.

    2013-01-01

    Fungi are important pathogens of human diseases, as well as to agricultural crop and trees. Molecular diagnostics can detect diseases early, and improve identification accuracy and follow-up disease management. The use of padlock probe is effective to facilitate these detections and pathogen

  11. Sequencing the Major Mycosphaerella Pathogens of Wheat and Banana

    NARCIS (Netherlands)

    Kema, G.H.J.

    2009-01-01

    Mycosphaerella is one of the largest genera of plant-pathogenic fungi with more than 1,000 named species, many of which are important pathogens causing leaf spotting diseases in a wide variety of crops including cereals, citrus, banana, eucalypts, soft fruits and horticultural crops. A few species

  12. Sequencing the Major Mycosphaerella Pathogens of Wheat and Banana

    NARCIS (Netherlands)

    Kema, G.H.; Dunkle, L.D.; Churchill, A.C.; Carlier, J.; James, A.; Souza, M.T.; Crous, P.W.; Roux, N.; Lee, T.A. van der; Wiitenberg, A.; Lindquist, E.; Grigoriev, I.; Bristow, J.; Goodwin, S.B.

    2007-01-01

    Mycosphaerella is one of the largest genera of plant pathogenic fungi with more than 1,000 named species, many of which are important pathogens causing leaf spotting diseases in a wide variety of crops including cereals, citrus, banana, eucalypts, soft fruits, and horticultural crops. A few species

  13. Pathogenicity and fungicide sensitivity of the causal agent of ...

    African Journals Online (AJOL)

    The pathogenicity of the fungus and its cross-infection potential were determined on mango, avocado, papaya and banana fruits. The sensitivity of the pathogen to fungicides was determined by assessing radial mycelial growth on potato dextrose agar (PDA) amended with nine different fungicides (Bendazim, Funguran, ...

  14. The genomic organization of plant pathogenicity in Fusarium species

    NARCIS (Netherlands)

    Rep, M.; Kistler, H.C.

    2010-01-01

    Comparative genomics is a powerful tool to infer the molecular basis of fungal pathogenicity and its evolution by identifying differences in gene content and genomic organization between fungi with different hosts or modes of infection. Through comparative analysis, pathogenicity-related chromosomes

  15. Antibiogram profile of pathogens isolated from processed cow meat ...

    African Journals Online (AJOL)

    ... the antibiotic resistance tests revealed varied, but interesting susceptibility patterns. Our findings does highlight the fact that there exist obvious vehicles for pathogenic bacteria proliferation within our abattoirs, and hence, the need for caution. Key words: Abattoirs, Bos taurus, Pathogenic bacteria, Antibiotics, Resistance ...

  16. Food-borne pathogens. Is there a remedy

    Energy Technology Data Exchange (ETDEWEB)

    Niemand, J G

    1985-03-01

    The Salmonella scare reinforced the importance of never taking chances when it comes to controlling pathogens. The issue has been resolved by radurisation. The article deals with the various pathogens that can effect food and argues the case for radurisation in dealing with them. It also looks at some of the other food products that can be treated using this process.

  17. Parasites and pathogens of ticks ( Rhipicephalus species Acari ...

    African Journals Online (AJOL)

    The interaction of ticks with its environment as well as its natural hosts predisposes it to acquiring pathogens that could pose animal and human health risks. Identifying these pathogens could alert dog owners and others to reassess the predisposing factors and ensure control. The aim of the study was to identify the species ...

  18. Ancient pathogen DNA in human teeth and petrous bones

    DEFF Research Database (Denmark)

    Margaryan, Ashot; Hansen, Henrik B.; Rasmussen, Simon

    2018-01-01

    Recent ancient DNA (aDNA) studies of human pathogens have provided invaluable insights into their evolutionary history and prevalence in space and time. Most of these studies were based on DNA extracted from teeth or postcranial bones. In contrast, no pathogen DNA has been reported from the petro...

  19. Challenges in Fusarium, a Trans-Kingdom Pathogen

    NARCIS (Netherlands)

    van Diepeningen, Anne D; de Hoog, G Sybren

    Fusarium species are emerging human pathogens, next to being plant pathogens. Problems with Fusarium are in their diagnostics and in their difficult treatment, but also in what are actual Fusarium species or rather Fusarium-like species. In this issue Guevara-Suarez et al. (Mycopathologia. doi:

  20. The epizootiology of the highly pathogenic avian influenza prior to ...

    African Journals Online (AJOL)

    The epizootiology of the highly pathogenic avian influenza prior to the anticipated pandemic of the early twenty first century. ... Transmission of highly pathogenic H5N1 from domestic fowls back to migratory waterfowl in western China has increased the geographic spread. This has grave consequences for the poultry ...

  1. Enteric pathogen modification by anaecic earthworm, Lampito Mauritii

    African Journals Online (AJOL)

    The biosolids from municipal wastewater treatment plant contains several enteric microbial pathogens, predominantly Salmonella and Escherichia species in the range of 15-18 x 104 CFU/g and 11-12 x 104 CFU/g respectively. The present study investigates the influence of earthworm, Lampito mauritii on enteric pathogen ...

  2. Aptamer-Based Technologies in Foodborne Pathogen Detection.

    Science.gov (United States)

    Teng, Jun; Yuan, Fang; Ye, Yingwang; Zheng, Lei; Yao, Li; Xue, Feng; Chen, Wei; Li, Baoguang

    2016-01-01

    Aptamers are single stranded DNA or RNA ligands, which can be selected by a method called systematic evolution of ligands by exponential enrichment (SELEX); and they can specifically recognize and bind to their targets. These unique characteristics of aptamers offer great potentials in applications such as pathogen detection and biomolecular screening. Pathogen detection is the critical means in detecting and identifying the problems related to public health and food safety; and only the rapid, sensitive and efficient detection technologies can enable the users to make the accurate assessments on the risks of infections (humans and animals) or contaminations (foods and other commodities) caused by various pathogens. This article reviews the development in the field of the aptamer-based approaches for pathogen detection, including whole-cell SELEX and Genomic SELEX. Nowadays, a variety of aptamer-based biosensors have been developed for pathogen detection. Thus, in this review, we also cover the development in aptamer-based biosensors including optical biosensors for multiple pathogen detection by multiple-labeling or label-free models such as fluorescence detection and surface plasmon resonance, electrochemical biosensors and lateral chromatography test strips, and their applications in pathogen detection and biomolecular screening. While notable progress has been made in the field in the last decade, challenges or drawbacks in their applications such as pathogen detection and biomolecular screening remain to be overcome.

  3. Genetic reprogramming of host cells by bacterial pathogens.

    Science.gov (United States)

    Tran Van Nhieu, Guy; Arbibe, Laurence

    2009-10-29

    During the course of infection, pathogens often induce changes in gene expression in host cells and these changes can be long lasting and global or transient and of limited amplitude. Defining how, when, and why bacterial pathogens reprogram host cells represents an exciting challenge that opens up the opportunity to grasp the essence of pathogenesis and its molecular details.

  4. Microbial transformation of (-)-isolongifolol by plant pathogenic fungus Glomerella cingulata.

    Science.gov (United States)

    Miyazawa, Mitsuo; Sakata, Kazuki; Ueda, Masashi

    2010-01-01

    The biotransformation of terpenoids using the plant pathogenic fungus as a biocatalyst to produce useful novel organic compounds was investigated. The biotransformation of sesquiterpen alcohol, (-)-isolongifolol (1) was investigated using plant pathogenic fungus Glomerella cingulata as a biocatalyst. Compound 1 was converted to (-)-(3R)-3-hydroxy-isolongifolol and (-)-(9R)-9-hydroxy-isolongifolol by G. cingulata.

  5. Lyophilization as a method for pathogens long term preservation

    Directory of Open Access Journals (Sweden)

    Milošević Mirjana B.

    2007-01-01

    Full Text Available Lyophilization (freeze-drying is one of the most suitable methods used for a long term preservation of pathogens. The aim of this paper was the application of lyophilization for storage of three significant plant pathogens: Fusarium graminearum, Helminthosporium gramineum, and Pseudomonas syringae pv. gylicinea, respectively. The plant material was collected continuously (during a four year period 2002-2006, depending on a plant development stage, from different localities in Vojvodina. Pathogens were isolated from diseased parts with characteristic symptoms, and placed on nutritive media specific for a certain pathogen, using standard phytopathological methods. Lyophilization was carried out in marked and coded ampoules by freezing and drying of pathogen suspension and nutritive medium. Revitalization of lyophilized isolates was done after four days. High percentage of revitalization was characteristic for all studied isolates, and it ranged from 85-92%, confirming that lyophilized pathogens would be capable of keeping viability for a long time in the collection. Besides above mentioned pathogens, there were 200 isolates in the collection, originating mostly from field and vegetable crops. Each isolate that was put into the Collection, was followed by all the necessary data such as: name of the pathogen, number of isolates, locality, host plant year of isolation, name of the researcher and other relevant data.

  6. The Shared Antibiotic Resistome of Soil Bacteria and Human Pathogens

    DEFF Research Database (Denmark)

    Forsberg, Kevin J.; Reyes, Alejandro; Wang, Bin

    2012-01-01

    protocol to assemble short-read sequence data after antibiotic selection experiments, using 12 different drugs in all antibiotic classes, and compared antibiotic resistance gene sequences between soil bacteria and clinically occurring pathogens. Sixteen sequences, representing seven gene products, were...... discovered in farmland soil bacteria within long stretches of perfect nucleotide identity with pathogenic proteobacteria....

  7. Aptamer-Based Technologies in Foodborne Pathogen Detection

    Directory of Open Access Journals (Sweden)

    Jun Teng

    2016-09-01

    Full Text Available Aptamers are single stranded DNA or RNA ligands, which can be selected by a method called systematic evolution of ligands by exponential enrichment (SELEX; and they can specifically recognize and bind to their targets. These unique characteristics of aptamers offer great potentials in applications such as pathogen detection and biomolecular screening. Pathogen detection is the first and critical means in detecting and identifying the problems related to public health and food safety; and only the rapid, sensitive and efficient detection technologies can enable the users to make to accurate assessments on the risk of infections (humans and animals or contaminations (foods and other commodities caused by various pathogens. This article reviews the developments in the field of the aptamer-based approaches for pathogen detection, including whole-cell SELEX and Genomic SELEX. Nowadays, a variety of aptamer-based biosensors have been developed for pathogen detection. Thus, in this review, we also cover the development of aptamer-based biosensors including optical biosensors for multiple pathogen detection in multiple-labeling or label-free models such as fluorescence detection and surface plasmon resonance, electrochemical biosensors, and lateral chromatography test strips, and their applications in the pathogen detection and biomolecular screening. While notable progress has been made in the field in the last decade, challenges or drawbacks in their applications such as pathogen detection and biomolecular screening, remain to be overcome.

  8. Rapidly expanding range of highly pathogenic avian influenza viruses

    Science.gov (United States)

    Hall, Jeffrey S.; Dusek, Robert J.; Spackman, Erica

    2015-01-01

    The movement of highly pathogenic avian influenza (H5N8) virus across Eurasia and into North America and the virus’ propensity to reassort with co-circulating low pathogenicity viruses raise concerns among poultry producers, wildlife biologists, aviculturists, and public health personnel worldwide. Surveillance, modeling, and experimental research will provide the knowledge required for intelligent policy and management decisions.

  9. Neonatal intensive care unit: Reservoirs of Nosocomial pathogens ...

    African Journals Online (AJOL)

    Improvement in the care and treatment of neonates had contributed to their increased survival. Nosocomial infection remains an important problem in intensive care units. Hospital wards had been shown to act as reservoirs of pathogenic microorganisms associated with infection. To assess the prevalence of pathogenic ...

  10. IPM potentials of microbial pathogens and diseases of mites

    NARCIS (Netherlands)

    van der Geest, L.P.S.; Ciancio, A.; Mukerji, K.G.

    2010-01-01

    An overview is given of diseases in mites, caused by infectious microorganisms. Many pathogens play an important role in the regulation of natural populations of mite populations and are for this reason subject of research on the feasibility to develop such pathogens to biological control agents.

  11. Damage mechanisms of pathogenic bacteria in drinking water ...

    African Journals Online (AJOL)

    This study aimed at elucidating the inactivation mechanisms of pathogenic bacteria in drinking water during chlorine and solar disinfection using a simple plating method. The well-known bacterial model Escherichia coli was used as pathogenic bacteria for the experiments. The damage mechanisms of E. coli were ...

  12. Pathogen removal using saturated sand colums supplemented with hydrochar

    NARCIS (Netherlands)

    Chung, J.W.

    2015-01-01

    This PhD study has evaluated hydrochars derived from biowastes as adsorbents for pathogen removal in water treatment. Pathogen removal experiments were conducted by carrying out breakthrough analysis using a simple sand filtration set-up. Glass columns packed by 10 cm sand bed supplemented with

  13. Phosphorylation and proteome dynamics in pathogen-resistant tomato plants

    NARCIS (Netherlands)

    Stulemeijer, I.J.E.

    2008-01-01

    Microbial plant pathogens impose a continuous threat on global food production. Similar to disease resistance in mammals, an innate immune system allows plants to recognise pathogens and swiftly activate defence. For the work described in this thesis, the interaction between tomato and the

  14. Bacterial Genome Engineering and Synthetic Biology: Combating Pathogens

    Science.gov (United States)

    2016-11-04

    extremely high genome sequence similarity between non-pathogenic and pathogenic strains by targeting small sequence variations present in the...Microbiol 2011, 14(5):524-531. 46. Bikard D, Euler CW, Jiang W, Nussenzweig PM, Goldberg GW, Duportet X, Fischetti VA, Marraffini LA: Exploiting

  15. Differential host susceptibility to Batrachochytrium dendrobatidis, an emerging amphibian pathogen

    Science.gov (United States)

    C.L. Searle; S.S. Gervasi; J. Hua; J.I. Hammond; R.A. Relyea; D.H. Olson; A.R. Blaustein

    2011-01-01

    The amphibian fungal pathogen Batrachochytrium dendrobatidis (Bd) has received considerable attention due to its role in amphibian population declines worldwide. Although many amphibian species appear to be affected by Bd, there is little information on species-specific differences in susceptibility to this pathogen. We used a comparative...

  16. The public health implications of pathogens in polluted aquatic ...

    African Journals Online (AJOL)

    The public health implications of pathogens in polluted aquatic ecosystems: a review. ... Pathogen contamination in water sources and related diseases constitute ... of public water supply and most importantly, increased rate of human mortality. ... illnesses related to respiratory, gastrointestinal and dermatological systems, ...

  17. Competition between yogurt probiotics and periodontal pathogens in vitro.

    Science.gov (United States)

    Zhu, Yunwo; Xiao, Liying; Shen, Da; Hao, Yuqing

    2010-09-01

    To investigate the competition between probiotics in bio-yogurt and periodontal pathogens in vitro. The antimicrobial activity of bio-yogurt was studied by agar diffusion assays, using eight species of putative periodontal pathogens and a 'protective bacteria' as indicator strains. Four probiotic bacterial species (Lactobacillus bulgaricus, Streptococcus thermophilus, Lactobacillus acidophilus, and Bifidobacterium) were isolated from yogurt and used to rate the competitive exclusion between probiotics and periodontal pathogens. Fresh yogurt inhibited all the periodontal pathogens included in this work, showing inhibition zones ranging from 9.3 (standard deviation 0.6) mm to 17.3 (standard deviation 1.7) mm, whereas heat-treated yogurt showed lower antimicrobial activity. In addition, neither fresh yogurt nor heat-treated yogurt inhibited the 'protective bacteria', Streptococcus sanguinis. The competition between yogurt probiotics and periodontal pathogens depended on the sequence of inoculation. When probiotics were inoculated first, Bifidobacterium inhibited Porphyromonas gingivalis, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans, Porphyromonas circumdentaria, and Prevotella nigrescens; L. acidophilus inhibited P. gingivalis, A. actinomycetemcomitans, P. circumdentaria, P. nigrescens, and Peptostreptococcus anaerobius; L. bulgaricus inhibited P. gingivalis, A. actinomycetemcomitans, and P. nigrescens; and S. thermophilus inhibited P. gingivalis, F. nucleatum, and P. nigrescens. However, their antimicrobial properties were reduced when both species (probiotics and periodontal pathogens) were inoculated simultaneously. When periodontal pathogens were inoculated first, Prevotella intermedia inhibited Bifidobacterium and S. thermophilus. The results demonstrated that bio-yogurt and the probiotics that it contains are capable of inhibiting specific periodontal pathogens but have no effect on the periodontal protective bacteria.

  18. Summary of taxa-specific research: 2. pathogens

    Science.gov (United States)

    Ned Klopfenstein; Brian Geils

    2009-01-01

    Damage caused by invasive forest pathogens is widely viewed as more severe, long-term, widespread, and difficult to restore than that caused by any other biological disturbance agent. In the last century, pathogens introduced into our native forests have threatened extinction of native tree species and critically degraded many different ecosystems across North America...

  19. Pathogenic microbial ancient DNA: a problem or an opportunity?

    DEFF Research Database (Denmark)

    Willerslev, Eske; Cooper, Alan

    2006-01-01

    cloning. Yet these studies have used mobile insertion elements (e.g. IS 6110 in tuberculosis) or conserved loci (e.g. 16S) to detect the presence of pathogens, and very similar or identical sequences have been reported from environmental bacteria (Gilbert et al. 2004). For example, Rollo & Marota (1999......We agree with Donoghue & Spigelman (2005) that, although pathogen studies hold great potential, any discussion requires a critical assessment of the results to date. However, we did note, as did Pääbo et al. (2004), that the field of ancient pathogen DNA still lacks a series of well......-controlled and rigorous studies that address technical issues and reliability criteria. This is unfortunate, as the rapid evolutionary rate of many pathogens offers a unique means to establish the authenticity of ancient pathogen sequences-since they should clearly be ancestral to modern genetic diversity (e.g. Reid et...

  20. Pathogens in drinking water: Are there any new ones

    Energy Technology Data Exchange (ETDEWEB)

    Reasoner, D.J.

    1993-01-01

    Since 1976 three newly recognized human pathogens have become familiar to the drinking water industry as waterborne disease agents. These are: the legionnaires disease agent, Legionella pneumophila and related species; and two protozoan pathogens, Giardia lamblia and Cryptosporidium parvum, both of which form highly disinfectant resistant cysts that are shed in the feces of infected individuals. The question frequently arises - are there other emerging waterborne pathogens that may pose a human health problem that the drinking water industry will have to deal with. The paper will review the current state of knowledge of the occurrence and incidence of pathogens and opportunistic pathogens other than Legionella, Giardia and Cryptosporidium in treated and untreated drinking water. Bacterial agents that will be reviewed include Aeromonas, Pseudomonas, Campylobacter, Mycobacterium, Yersinia and Plesiomonas. Aspects of detection of these agents including detection methods and feasibility of monitoring will be addressed.

  1. Detection of pathogens from periodontal lesions

    Directory of Open Access Journals (Sweden)

    Malheiros Veruska de João

    2004-01-01

    Full Text Available OBJECTIVE: To comparatively detect A. actinomycetemcomitans and F. nucleatum from periodontal and healthy sites. METHODS: Subgingival clinical samples from 50 periodontitis adult patients and 50 healthy subjects were analyzed. Both organisms were isolated using a trypticase soy agar-bacitracin-vancomycin (TSBV medium and detected by PCR. Conventional biochemical tests were used for bacteria identification. RESULTS: A. actinomycetemcomitans and F. nucleatum were isolated in 18% and 20% of the patients, respectively, and in 2% and 24% of healthy subjects. Among A. actinomycetemcomitans isolates, biotype II was the most prevalent. Primer pair AA was 100% sensitive in the detection of A. actinomycetemcomitans from both subject groups. Primers ASH and FU were also 100% sensitive to detect this organism in healthy subject samples. Primer pair FN5047 was more sensitive to detect F. nucleatum in patients or in healthy samples than primer 5059S. Primers ASH and 5059S were more specific in the detection of A. actinomycetemcomitans and F. nucleatum, respectively, in patients and in healthy subject samples. CONCLUSIONS: PCR is an effective tool for detecting periodontal pathogens in subgingival samples, providing a faster and safer diagnostic tool of periodontal diseases. The method's sensitivity and specificity is conditioned by the choice of the set of primers used.

  2. Actinobaculum schaalii an emerging pediatric pathogen?

    Directory of Open Access Journals (Sweden)

    Zimmermann Petra

    2012-08-01

    Full Text Available Abstract Background Actinobaculum schaalii was first described as a causative agent for human infection in 1997. Since then it has mainly been reported causing urinary tract infections (UTI in elderly individuals with underlying urological diseases. Isolation and identification is challenging and often needs molecular techniques. A. schaalii is increasingly reported as a cause of infection in humans, however data in children is very limited. Case presentation We present the case of an 8-month-old Caucasian boy suffering from myelomeningocele and neurogenic bladder who presented with a UTI. An ultrasound of the urinary tract was unremarkable. Urinalysis and microscopy showed an elevated leukocyte esterase test, pyuria and a high number of bacteria. Empiric treatment with oral co-trimoxazole was started. Growth of small colonies of Gram-positive rods was observed after 48 h. Sequencing of the 16S rRNA gene confirmed an A. schaalii infection 9 days later. Treatment was changed to oral amoxicillin for 14 days. On follow-up urinalysis was normal and urine cultures were negative. Conclusions A.schaalii is an emerging pathogen in adults and children. Colonization and subsequent infection seem to be influenced by the age of the patient. In young children with high suspicion of UTI who use diapers or in children who have known abnormalities of their urogenital tract, infection with A. schaalii should be considered and empiric antimicrobial therapy chosen accordingly.

  3. Autonomous system for pathogen detection and identification

    International Nuclear Information System (INIS)

    Belgrader, P.; Benett, W.; Langlois, R.; Long, G.; Mariella, R.; Milanovich, F.; Miles, R.; Nelson, W.; Venkateswaran, K.

    1998-01-01

    This purpose of this project is to build a prototype instrument that will, running unattended, detect, identify, and quantify BW agents. In order to accomplish this, we have chosen to start with the world s leading, proven, assays for pathogens: surface-molecular recognition assays, such as antibody-based assays, implemented on a high-performance, identification (ID)-capable flow cytometer, and the polymerase chain reaction (PCR) for nucleic-acid based assays. With these assays, we must integrate the capability to: l collect samples from aerosols, water, or surfaces; l perform sample preparation prior to the assays; l incubate the prepared samples, if necessary, for a period of time; l transport the prepared, incubated samples to the assays; l perform the assays; l interpret and report the results of the assays. Issues such as reliability, sensitivity and accuracy, quantity of consumables, maintenance schedule, etc. must be addressed satisfactorily to the end user. The highest possible sensitivity and specificity of the assay must be combined with no false alarms. Today, we have assays that can, in under 30 minutes, detect and identify stimulants for BW agents at concentrations of a few hundred colony-forming units per ml of solution. If the bio-aerosol sampler of this system collects 1000 Ymin and concentrates the respirable particles into 1 ml of solution with 70% processing efficiency over a period of 5 minutes, then this translates to a detection/ID capability of under 0.1 agent-containing particle/liter of air

  4. The intrinsic resistome of bacterial pathogens.

    Science.gov (United States)

    Olivares, Jorge; Bernardini, Alejandra; Garcia-Leon, Guillermo; Corona, Fernando; B Sanchez, Maria; Martinez, Jose L

    2013-01-01

    Intrinsically resistant bacteria have emerged as a relevant health problem in the last years. Those bacterial species, several of them with an environmental origin, present naturally low-level susceptibility to several drugs. It has been proposed that intrinsic resistance is mainly the consequence of the impermeability of cellular envelopes, the activity of multidrug efflux pumps or the lack of appropriate targets for a given family of drugs. However, recently published articles indicate that the characteristic phenotype of susceptibility to antibiotics of a given bacterial species depends on the concerted activity of several elements, what has been named as intrinsic resistome. These determinants comprise not just classical resistance genes. Other elements, several of them involved in basic bacterial metabolic processes, are of relevance for the intrinsic resistance of bacterial pathogens. In the present review we analyze recent publications on the intrinsic resistomes of Escherichia coli and Pseudomonas aeruginosa. We present as well information on the role that global regulators of bacterial metabolism, as Crc from P. aeruginosa, may have on modulating bacterial susceptibility to antibiotics. Finally, we discuss the possibility of searching inhibitors of the intrinsic resistome in the aim of improving the activity of drugs currently in use for clinical practice.

  5. The intrinsic resistome of bacterial pathogens

    Directory of Open Access Journals (Sweden)

    Jorge Andrés Olivares Pacheco

    2013-04-01

    Full Text Available Intrinsically resistant bacteria have emerged as a relevant health problem in the last years. Those bacterial species, several of them with an environmental origin, present naturally a low-level susceptibility to several drugs. It has been proposed that intrinsic resistance is mainly the consequence of the impermeability of cellular envelopes, the activity of multidrug efflux pumps or the lack of appropriate targets for a given family of drugs. However, recently published articles indicate that the characteristic phenotype of susceptibility to antibiotics of a given bacterial species depends on the concerted activity of several elements, what has been named as intrinsic resistome. These determinants comprise not just classical resistance genes. Other elements, several of them involved in basic bacterial metabolic processes, are of relevance for the intrinsic resistance of bacterial pathogens. In the present review we analyse recent publications on the intrinsic resistomes of Escherichia coli and Pseudomonas aeruginosa. We present as well information on the role that global regulators of bacterial metabolism, as Crc from P. aeruginosa, may have on modulating bacterial susceptibility to antibiotics. Finally, we discuss the possibility of searching inhibitors of the intrinsic resistome in the aim of improving the activity of drugs currently in use for clinical practice.

  6. Genome of the opportunistic pathogen Streptococcus sanguinis.

    Science.gov (United States)

    Xu, Ping; Alves, Joao M; Kitten, Todd; Brown, Arunsri; Chen, Zhenming; Ozaki, Luiz S; Manque, Patricio; Ge, Xiuchun; Serrano, Myrna G; Puiu, Daniela; Hendricks, Stephanie; Wang, Yingping; Chaplin, Michael D; Akan, Doruk; Paik, Sehmi; Peterson, Darrell L; Macrina, Francis L; Buck, Gregory A

    2007-04-01

    The genome of Streptococcus sanguinis is a circular DNA molecule consisting of 2,388,435 bp and is 177 to 590 kb larger than the other 21 streptococcal genomes that have been sequenced. The G+C content of the S. sanguinis genome is 43.4%, which is considerably higher than the G+C contents of other streptococci. The genome encodes 2,274 predicted proteins, 61 tRNAs, and four rRNA operons. A 70-kb region encoding pathways for vitamin B(12) biosynthesis and degradation of ethanolamine and propanediol was apparently acquired by horizontal gene transfer. The gene complement suggests new hypotheses for the pathogenesis and virulence of S. sanguinis and differs from the gene complements of other pathogenic and nonpathogenic streptococci. In particular, S. sanguinis possesses a remarkable abundance of putative surface proteins, which may permit it to be a primary colonizer of the oral cavity and agent of streptococcal endocarditis and infection in neutropenic patients.

  7. Photodynamic inactivation of pathogens causing infectious keratitis

    Science.gov (United States)

    Simon, Carole; Wolf, G.; Walther, M.; Winkler, K.; Finke, M.; Hüttenberger, D.; Bischoff, Markus; Seitz, B.; Cullum, J.; Foth, H.-J.

    2014-03-01

    The increasing prevalence of antibiotic resistance requires new approaches also for the treatment of infectious keratitis. Photodynamic Inactivation (PDI) using the photosensitizer (PS) Chlorin e6 (Ce6) was investigated as an alternative to antibiotic treatment. An in-vitro cornea model was established using porcine eyes. The uptake of Ce6 by bacteria and the diffusion of the PS in the individual layers of corneal tissue were investigated by fluorescence. After removal of the cornea's epithelium Ce6-concentrations tested in liquid culture against different concentrations of Ce6 (1 - 512 μM) using 10 minutes irradiation (E = 18 J/cm2 ). This demonstrated that a complete inactivation of the pathogen strains were feasible whereby SA was slightly more susceptible than PA. 3909 mutants of the Keio collection of Escherichia coli (E.coli) were screened for potential resistance factors. The sensitive mutants can be grouped into three categories: transport mutants, mutants in lipopolysaccharide synthesis and mutants in the bacterial SOS-response. In conclusion PDI is seen as a promising therapy concept for infectious keratitis.

  8. The neglected intrinsic resistome of bacterial pathogens.

    Directory of Open Access Journals (Sweden)

    Alicia Fajardo

    Full Text Available Bacteria with intrinsic resistance to antibiotics are a worrisome health problem. It is widely believed that intrinsic antibiotic resistance of bacterial pathogens is mainly the consequence of cellular impermeability and activity of efflux pumps. However, the analysis of transposon-tagged Pseudomonas aeruginosa mutants presented in this article shows that this phenotype emerges from the action of numerous proteins from all functional categories. Mutations in some genes make P. aeruginosa more susceptible to antibiotics and thereby represent new targets. Mutations in other genes make P. aeruginosa more resistant and therefore define novel mechanisms for mutation-driven acquisition of antibiotic resistance, opening a new research field based in the prediction of resistance before it emerges in clinical environments. Antibiotics are not just weapons against bacterial competitors, but also natural signalling molecules. Our results demonstrate that antibiotic resistance genes are not merely protective shields and offer a more comprehensive view of the role of antibiotic resistance genes in the clinic and in nature.

  9. Pathogen Decontamination of Food Crop Soil: A Review.

    Science.gov (United States)

    Gurtler, Joshua B

    2017-09-01

    The purpose of this review is to delineate means of decontaminating soil. This information might be used to mitigate soil-associated risks of foodborne pathogens. The majority of the research in the published literature involves inactivation of plant pathogens in soil, i.e., those pathogens harmful to fruit and vegetable production and ornamental plants. Very little has been published regarding the inactivation of foodborne human pathogens in crop soil. Nevertheless, because decontamination techniques for plant pathogens might also be useful methods for eliminating foodborne pathogens, this review also includes inactivation of plant pathogens, with appropriate discussion and comparisons, in the hopes that these methods may one day be validated against foodborne pathogens. Some of the major soil decontamination methods that have been investigated and are covered include chemical decontamination (chemigation), solarization, steaming, biofumigation, bacterial competitive exclusion, torch flaming, microwave treatment, and amendment with biochar. Other innovative means of inactivating foodborne pathogens in soils may be discovered and explored in the future, provided that these techniques are economically feasible in terms of chemicals, equipment, and labor. Food microbiology and food safety researchers should reach out to soil scientists and plant pathologists to create links where they do not currently exist and strengthen relationships where they do exist to take advantage of multidisciplinary skills. In time, agricultural output and the demand for fresh produce will increase. With advances in the sensitivity of pathogen testing and epidemiological tracebacks, the need to mitigate preharvest bacterial contamination of fresh produce will become paramount. Hence, soil decontamination technologies may become more economically feasible and practical in light of increasing the microbial safety of fresh produce.

  10. Using the Pathogen-Host Interactions database (PHI-base to investigate plant pathogen genomes and genes implicated in virulence

    Directory of Open Access Journals (Sweden)

    Martin eUrban

    2015-08-01

    Full Text Available New pathogen-host interaction mechanisms can be revealed by integrating mutant phenotype data with genetic information. PHI-base is a multi-species manually curated database combining peer-reviewed published phenotype data from plant and animal pathogens and gene/protein information in a single database.

  11. A network approach to predict pathogenic genes for Fusarium graminearum.

    Directory of Open Access Journals (Sweden)

    Xiaoping Liu

    Full Text Available Fusarium graminearum is the pathogenic agent of Fusarium head blight (FHB, which is a destructive disease on wheat and barley, thereby causing huge economic loss and health problems to human by contaminating foods. Identifying pathogenic genes can shed light on pathogenesis underlying the interaction between F. graminearum and its plant host. However, it is difficult to detect pathogenic genes for this destructive pathogen by time-consuming and expensive molecular biological experiments in lab. On the other hand, computational methods provide an alternative way to solve this problem. Since pathogenesis is a complicated procedure that involves complex regulations and interactions, the molecular interaction network of F. graminearum can give clues to potential pathogenic genes. Furthermore, the gene expression data of F. graminearum before and after its invasion into plant host can also provide useful information. In this paper, a novel systems biology approach is presented to predict pathogenic genes of F. graminearum based on molecular interaction network and gene expression data. With a small number of known pathogenic genes as seed genes, a subnetwork that consists of potential pathogenic genes is identified from the protein-protein interaction network (PPIN of F. graminearum, where the genes in the subnetwork are further required to be differentially expressed before and after the invasion of the pathogenic fungus. Therefore, the candidate genes in the subnetwork are expected to be involved in the same biological processes as seed genes, which imply that they are potential pathogenic genes. The prediction results show that most of the pathogenic genes of F. graminearum are enriched in two important signal transduction pathways, including G protein coupled receptor pathway and MAPK signaling pathway, which are known related to pathogenesis in other fungi. In addition, several pathogenic genes predicted by our method are verified in other

  12. Pathogen dynamics in a partial migrant : Interactions between mallards (Anas platyrhynchos) and avian influenza viruses

    NARCIS (Netherlands)

    Dijk, J.G.B. van

    2014-01-01

    Zoonotic pathogens may pose a serious threat for humans, requiring a better understanding of the ecology and transmission of these pathogens in their natural (wildlife) hosts. The zoonotic pathogen studied in this thesis is low pathogenic avian influenza virus (LPAIV). This pathogen circulates

  13. Understanding the Pathogenicity of Burkholderia contaminans, an Emerging Pathogen in Cystic Fibrosis.

    Science.gov (United States)

    Nunvar, Jaroslav; Kalferstova, Lucie; Bloodworth, Ruhi A M; Kolar, Michal; Degrossi, Jose; Lubovich, Silvina; Cardona, Silvia T; Drevinek, Pavel

    2016-01-01

    Several bacterial species from the Burkholderia cepacia complex (Bcc) are feared opportunistic pathogens that lead to debilitating lung infections with a high risk of developing fatal septicemia in cystic fibrosis (CF) patients. However, the pathogenic potential of other Bcc species is yet unknown. To elucidate clinical relevance of Burkholderia contaminans, a species frequently isolated from CF respiratory samples in Ibero-American countries, we aimed to identify its key virulence factors possibly linked with an unfavorable clinical outcome. We performed a genome-wide comparative analysis of two isolates of B. contaminans ST872 from sputum and blood culture of a female CF patient in Argentina. RNA-seq data showed significant changes in expression for quorum sensing-regulated virulence factors and motility and chemotaxis. Furthermore, we detected expression changes in a recently described low-oxygen-activated (lxa) locus which encodes stress-related proteins, and for two clusters responsible for the biosynthesis of antifungal and hemolytic compounds pyrrolnitrin and occidiofungin. Based on phenotypic assays that confirmed changes in motility and in proteolytic, hemolytic and antifungal activities, we were able to distinguish two phenotypes of B. contaminans that coexisted in the host and entered her bloodstream. Whole genome sequencing revealed that the sputum and bloodstream isolates (each representing a distinct phenotype) differed by over 1,400 mutations as a result of a mismatch repair-deficient hypermutable state of the sputum isolate. The inferred lack of purifying selection against nonsynonymous mutations and the high rate of pseudogenization in the derived isolate indicated limited evolutionary pressure during evolution in the nutrient-rich, stable CF sputum environment. The present study is the first to examine the genomic and transcriptomic differences between longitudinal isolates of B. contaminans. Detected activity of a number of putative virulence

  14. Environmental Factors and Zoonotic Pathogen Ecology in Urban Exploiter Species.

    Science.gov (United States)

    Rothenburger, Jamie L; Himsworth, Chelsea H; Nemeth, Nicole M; Pearl, David L; Jardine, Claire M

    2017-09-01

    Knowledge of pathogen ecology, including the impacts of environmental factors on pathogen and host dynamics, is essential for determining the risk that zoonotic pathogens pose to people. This review synthesizes the scientific literature on environmental factors that influence the ecology and epidemiology of zoonotic microparasites (bacteria, viruses and protozoa) in globally invasive urban exploiter wildlife species (i.e., rock doves [Columba livia domestica], European starlings [Sturnus vulgaris], house sparrows [Passer domesticus], Norway rats [Rattus norvegicus], black rats [R. rattus] and house mice [Mus musculus]). Pathogen ecology, including prevalence and pathogen characteristics, is influenced by geographical location, habitat, season and weather. The prevalence of zoonotic pathogens in mice and rats varies markedly over short geographical distances, but tends to be highest in ports, disadvantaged (e.g., low income) and residential areas. Future research should use epidemiological approaches, including random sampling and robust statistical analyses, to evaluate a range of biotic and abiotic environmental factors at spatial scales suitable for host home range sizes. Moving beyond descriptive studies to uncover the causal factors contributing to uneven pathogen distribution among wildlife hosts in urban environments may lead to targeted surveillance and intervention strategies. Application of this knowledge to urban maintenance and planning may reduce the potential impacts of urban wildlife-associated zoonotic diseases on people.

  15. Detection of mastitis pathogens by analysis of volatile bacterial metabolites.

    Science.gov (United States)

    Hettinga, K A; van Valenberg, H J F; Lam, T J G M; van Hooijdonk, A C M

    2008-10-01

    The ability to detect mastitis pathogens based on their volatile metabolites was studied. Milk samples from cows with clinical mastitis, caused by Staphylococcus aureus, coagulase-negative staphylococci, Streptococcus uberis, Streptococcus dysgalactiae, and Escherichia coli were collected. In addition, samples from cows without clinical mastitis and with low somatic cell count (SCC) were collected for comparison. All mastitis samples were examined by using classical microbiological methods, followed by headspace analysis for volatile metabolites. Milk from culture-negative samples contained a lower number and amount of volatile components compared with cows with clinical mastitis. Because of variability between samples within a group, comparisons between pathogens were not sufficient for classification of the samples by univariate statistics. Therefore, an artificial neural network was trained to classify the pathogen in the milk samples based on the bacterial metabolites. The trained network differentiated milk from uninfected and infected quarters very well. When comparing pathogens, Staph. aureus produced a very different pattern of volatile metabolites compared with the other samples. Samples with coagulase-negative staphylococci and E. coli had enough dissimilarity with the other pathogens, making it possible to separate these 2 pathogens from each other and from the other samples. The 2 streptococcus species did not show significant differences between each other but could be identified as a different group from the other pathogens. Five groups can thus be identified based on the volatile bacterial metabolites: Staph. aureus, coagulase-negative staphylococci, streptococci (Strep. uberis and Strep. dysgalactiae as one group), E. coli, and uninfected quarters.

  16. Purification and proteomics of pathogen-modified vacuoles and membranes

    Directory of Open Access Journals (Sweden)

    Jo-Ana eHerweg

    2015-06-01

    Full Text Available Certain pathogenic bacteria adopt an intracellular lifestyle and proliferate in eukaryotic host cells. The intracellular niche protects the bacteria from cellular and humoral components of the mammalian immune system, and at the same time, allows the bacteria to gain access to otherwise restricted nutrient sources. Yet, intracellular protection and access to nutrients comes with a price, i.e. the bacteria need to overcome cell-autonomous defense mechanisms, such as the bactericidal endocytic pathway. While a few bacteria rupture the early phagosome and escape into the host cytoplasm, most intracellular pathogens form a distinct, degradation-resistant and replication-permissive membranous compartment. Intracellular bacteria that form unique pathogen vacuoles include Legionella, Mycobacterium, Chlamydia, Simkania and Salmonella species. In order to understand the formation of these pathogen niches on a global scale and in a comprehensive and quantitative manner, an inventory of compartment-associated host factors is required. To this end, the intact pathogen compartments need to be isolated, purified and biochemically characterized. Here, we review recent progress on the isolation and purification of pathogen-modified vacuoles and membranes, as well as their proteomic characterization by mass spectrometry and different validation approaches. These studies provide the basis for further investigations on the specific mechanisms of pathogen-driven compartment formation.

  17. Pathogenic lysosomal depletion in Parkinson's disease.

    Science.gov (United States)

    Dehay, Benjamin; Bové, Jordi; Rodríguez-Muela, Natalia; Perier, Celine; Recasens, Ariadna; Boya, Patricia; Vila, Miquel

    2010-09-15

    Mounting evidence suggests a role for autophagy dysregulation in Parkinson's disease (PD). The bulk degradation of cytoplasmic proteins (including α-synuclein) and organelles (such as mitochondria) is mediated by macroautophagy, which involves the sequestration of cytosolic components into autophagosomes (AP) and its delivery to lysosomes. Accumulation of AP occurs in postmortem brain samples from PD patients, which has been widely attributed to an induction of autophagy. However, the cause and pathogenic significance of these changes remain unknown. Here we found in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine mouse model of PD that AP accumulation and dopaminergic cell death are preceded by a marked decrease in the amount of lysosomes within dopaminergic neurons. Lysosomal depletion was secondary to the abnormal permeabilization of lysosomal membranes induced by increased mitochondrial-derived reactive oxygen species. Lysosomal permeabilization resulted in a defective clearance and subsequent accumulation of undegraded AP and contributed directly to neurodegeneration by the ectopic release of lysosomal proteases into the cytosol. Lysosomal breakdown and AP accumulation also occurred in PD brain samples, where Lewy bodies were strongly immunoreactive for AP markers. Induction of lysosomal biogenesis by genetic or pharmacological activation of lysosomal transcription factor EB restored lysosomal levels, increased AP clearance and attenuated 1-methyl-4-phenylpyridinium-induced cell death. Similarly, the autophagy-enhancer compound rapamycin attenuated PD-related dopaminergic neurodegeneration, both in vitro and in vivo, by restoring lysosomal levels. Our results indicate that AP accumulation in PD results from defective lysosomal-mediated AP clearance secondary to lysosomal depletion. Restoration of lysosomal levels and function may thus represent a novel neuroprotective strategy in PD.

  18. Bioactive proteins against pathogenic and spoilage bacteria

    Directory of Open Access Journals (Sweden)

    Mahmoud Z. Sitohy

    2014-10-01

    Full Text Available Background: It is likely that both human nutrition and the nutrition of livestock are benefited by the presence of bioactive proteins within their respective diet regimes. Bioactive proteins have been defined as specific protein fragments that positively impact bodily functions or conditions and may, ultimately, influence overall human health. The ingestion of bioactive proteins may have an effect on the major body systems—namely, the cardiovascular, digestive, immune and nervous systems. According to their functional properties, bioactive proteins may be classified as antimicrobial, antithrombotic, antihypertensive, opioid, immune-modulatory, mineral binding and anti-oxidative. There are many examples of biologically active food proteins and active peptides that can be obtained from various food protein sources. They have a physiological significance beyond the pure nutritional requirements; in other wordsthey have the acquisition of nitrogen for normal growth and maintenance. Objective: This study aims to specify and characterize the extent and mode of action of bioactive proteins in their native form, (glycinin, glycinin basic sub-unit and β-conglycinin against specific main pathogens (Listeria monocytogenes, Escherichia coli O157:H7 and Salmonella enterica serovar Enteritidis. We will be using standard media while identifying the main constituents responsible for this action. Methods: Glycinin, basic sub-unit and β-conglycinin were isolated from soybean protein and tested for their antimicrobial action against pathogenic and spoilage bacteria, They were thencompared to the properties of penicillin. Methylated soybean protein and also methylated chickpea protein (MSP and MCP, with isoelectric points around pI 8, were prepared by esterifying. 83 % of their free carboxyl groups and their interactions with Gram positive and Gram negative bacteria were examined. Results: The three divisions of cationic proteins exhibited antibacterial

  19. Impact of climate trends on tick-borne pathogen transmission

    Directory of Open Access Journals (Sweden)

    Agustin eEstrada-Pena

    2012-03-01

    Full Text Available Recent advances in climate research together with a better understanding of tick-pathogen interactions, the distribution of ticks and the diagnosis of tick-borne pathogens raise questions about the impact of environmental factors on tick abundance and spread and the prevalence and transmission of tick-borne pathogens. While undoubtedly climate plays a role in the changes in distribution and seasonal abundance of ticks, it is always difficult to disentangle factors impacting on the abundance of tick hosts from those exerted by human habits. All together, climate, host abundance and social factors may explain the upsurge of epidemics transmitted by ticks to humans. Herein we focused on tick-borne pathogens that affect humans with pandemic potential. Borrelia burgdorferi s.l. (Lyme disease, Anaplasma phagocytophilum (human granulocytic anaplasmosis and tick-borne encephalitis virus (tick-borne encephalitis are transmitted by Ixodes spp. Crimean-Congo hemorrhagic fever virus (Crimean-Congo hemorrhagic fever is transmitted by Hyalomma spp. In this review, we discussed how vector tick species occupy the habitat as a function of different climatic factors, and how these factors impact on tick survival and seasonality. How molecular events at the tick-pathogen interface impact on pathogen transmission is also discussed. Results from statistically and biologically derived models are compared to show that while statistical models are able to outline basic information about tick distributions, biologically derived models are necessary to evaluate pathogen transmission rates and understand the effect of climatic variables and host abundance patterns on pathogen transmission. The results of these studies could be used to build early alert systems able to identify the main factors driving the subtle changes in tick distribution and seasonality and the prevalence of tick-borne pathogens.

  20. The value of pathogen information in treating clinical mastitis.

    Science.gov (United States)

    Cha, Elva; Smith, Rebecca L; Kristensen, Anders R; Hertl, Julia A; Schukken, Ynte H; Tauer, Loren W; Welcome, Frank L; Gröhn, Yrjö T

    2016-11-01

    The objective of this study was to determine the economic value of obtaining timely and more accurate clinical mastitis (CM) test results for optimal treatment of cows. Typically CM is first identified when the farmer observes recognisable outward signs. Further information of whether the pathogen causing CM is Gram-positive, Gram-negative or other (including no growth) can be determined by using on-farm culture methods. The most detailed level of information for mastitis diagnostics is obtainable by sending milk samples for culture to an external laboratory. Knowing the exact pathogen permits the treatment method to be specifically targeted to the causation pathogen, resulting in less discarded milk. The disadvantages are the additional waiting time to receive test results, which delays treating cows, and the cost of the culture test. Net returns per year (NR) for various levels of information were estimated using a dynamic programming model. The Value of Information (VOI) was then calculated as the difference in NR using a specific level of information as compared to more detailed information on the CM causative agent. The highest VOI was observed where the farmer assumed the pathogen causing CM was the one with the highest incidence in the herd and no pathogen specific CM information was obtained. The VOI of pathogen specific information, compared with non-optimal treatment of Staphylococcus aureus where recurrence and spread occurred due to lack of treatment efficacy, was $20.43 when the same incorrect treatment was applied to recurrent cases, and $30.52 when recurrent cases were assumed to be the next highest incidence pathogen and treated accordingly. This indicates that negative consequences associated with choosing the wrong CM treatment can make additional information cost-effective if pathogen identification is assessed at the generic information level and if the pathogen can spread to other cows if not treated appropriately.

  1. Multiple sample flow through immunomagnetic separator for concentrating pathogenic bacteria

    International Nuclear Information System (INIS)

    Rotariu, Ovidiu; Ogden, Iain D; MacRae, Marion; Udrea, Laura Elena; Strachan, Norval J C

    2005-01-01

    The standard method of immunomagnetic separation for isolating pathogenic bacteria from food and environmental matrices processes 1 ml volumes. Pathogens present at low levels ( 97% recovery of polydisperse magnetic particles (diameter range 1 to 8 μm) containing 29-33% w/w Fe 3 O 4 content. Between 70 and 130 times more of the pathogenic bacteria Escherichia coli O157 is recovered from PBS compared with the standard 1 ml method. Also, the recovery of E. coli O157 from beef mince homogenates, after a 4 h incubation at 42 deg. C, is between 80 and 180 times higher than the standard 1 ml method

  2. Methods to classify bacterial pathogens in cystic fibrosis

    DEFF Research Database (Denmark)

    Bjarnsholt, Thomas; Nielsen, Xiaohui Chen; Johansen, Ulla

    2011-01-01

    for identification of isolates from the Burkholderia complex to the species level. DNA typing by PFGE, which can be used for any bacterial pathogen, is described as it is employed for Pseudomonas aeruginosa. A commercially available ELISA method is described for measuring IgG antibodies against P. aeruginosa in CF......Many bacteria can be detected in CF sputum, pathogenic and commensal. Modified Koch's criteria for identification of established and emerging CF pathogens are therefore described. Methods are described to isolate bacteria and to detect bacterial biofilms in sputum or lung tissue from CF patients...

  3. [Highly pathogenic avian influenza--monitoring of migratory waterfowl].

    Science.gov (United States)

    Otsuki, Koichi; Ito, Toshihiro

    2006-10-01

    Since 1979, the group belonging to Departments of Veterinary Microbiology, Veterinary Public Health and the Avian Zoonoses Research Centre, Faculty of Agriculture, Tottori University is continuing isolation of avian influenza virus from such migratory waterfowls as whistling swan, pintail and tufted dugs flying from Siberia and/or northern China. They have already isolated many interesting influenza viruses. Serotype of the isolates is various; some H5 and H7 and human types of viruses were also isolated; and its pathogenicity for chickens is not high. It was interested that low pathogenic H5N3 virus isolated from whistling swan acquired severe pathogenicity during passage in chicks.

  4. Chromatin versus pathogens: the function of epigenetics in plant immunity

    Science.gov (United States)

    Ding, Bo; Wang, Guo-Liang

    2015-01-01

    To defend against pathogens, plants have developed a sophisticated innate immunity that includes effector recognition, signal transduction, and rapid defense responses. Recent evidence has demonstrated that plants utilize the epigenetic control of gene expression to fine-tune their defense when challenged by pathogens. In this review, we highlight the current understanding of the molecular mechanisms of histone modifications (i.e., methylation, acetylation, and ubiquitination) and chromatin remodeling that contribute to plant immunity against pathogens. Functions of key histone-modifying and chromatin remodeling enzymes are discussed. PMID:26388882

  5. Widespread occurrence of honey bee pathogens in solitary bees.

    Science.gov (United States)

    Ravoet, Jorgen; De Smet, Lina; Meeus, Ivan; Smagghe, Guy; Wenseleers, Tom; de Graaf, Dirk C

    2014-10-01

    Solitary bees and honey bees from a neighbouring apiary were screened for a broad set of putative pathogens including protists, fungi, spiroplasmas and viruses. Most sampled bees appeared to be infected with multiple parasites. Interestingly, viruses exclusively known from honey bees such as Apis mellifera Filamentous Virus and Varroa destructor Macula-like Virus were also discovered in solitary bees. A microsporidium found in Andrena vaga showed most resemblance to Nosema thomsoni. Our results suggest that bee hives represent a putative source of pathogens for other pollinators. Similarly, solitary bees may act as a reservoir of honey bee pathogens. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Parallels in amphibian and bat declines from pathogenic fungi.

    Science.gov (United States)

    Eskew, Evan A; Todd, Brian D

    2013-03-01

    Pathogenic fungi have substantial effects on global biodiversity, and 2 emerging pathogenic species-the chytridiomycete Batrachochytrium dendrobatidis, which causes chytridiomycosis in amphibians, and the ascomycete Geomyces destructans, which causes white-nose syndrome in hibernating bats-are implicated in the widespread decline of their vertebrate hosts. We synthesized current knowledge for chytridiomycosis and white-nose syndrome regarding disease emergence, environmental reservoirs, life history characteristics of the host, and host-pathogen interactions. We found striking similarities between these aspects of chytridiomycosis and white-nose syndrome, and the research that we review and propose should help guide management of future emerging fungal diseases.

  7. Quantifying the impact of climate change on enteric waterborne pathogen concentrations in surface water

    NARCIS (Netherlands)

    Hofstra, N.

    2011-01-01

    Climate change, among other factors, will impact waterborne pathogen concentrations in surface water worldwide, possibly increasing the risk of diseases caused by these pathogens. So far, the impacts are only determined qualitatively and thorough quantitative estimates of future pathogen

  8. Foliar aphid feeding recruits rhizosphere bacteria and primes plant immunity against pathogenic and non-pathogenic bacteria in pepper.

    Science.gov (United States)

    Lee, Boyoung; Lee, Soohyun; Ryu, Choong-Min

    2012-07-01

    Plants modulate defence signalling networks in response to different biotic stresses. The present study evaluated the effect of a phloem-sucking aphid on plant defence mechanisms in pepper (Capsicum annuum) during subsequent pathogen attacks on leaves and rhizosphere bacteria on roots. Plants were pretreated with aphids and/or the chemical trigger benzothiadiazol (BTH) 7 d before being challenged with two pathogenic bacteria, Xanthomonas axonopodis pv. vesicatoria (Xav) as a compatible pathogen and X. axonopodis pv. glycines (Xag) as an incompatible (non-host) pathogen. Disease severity was noticeably lower in aphid- and BTH + aphid-treated plants than in controls. Although treatment with BTH or aphids alone did not affect the hypersensitive response (HR) against Xag strain 8ra, the combination treatment had a synergistic effect on the HR. The aphid population was reduced by BTH pretreatment and by combination treatment with BTH and bacterial pathogens in a synergistic manner. Analysis of the expression of the defence-related genes Capsicum annum pathogenesis-related gene 9 (CaPR9), chitinase 2 (CaCHI2), SAR8·2 and Lipoxygenase1 (CaLOX1) revealed that aphid infestation resulted in the priming of the systemic defence responses against compatible and incompatible pathogens. Conversely, pre-challenge with the compatible pathogen Xav on pepper leaves significantly reduced aphid numbers. Aphid infestation increased the population of the beneficial Bacillus subtilis GB03 but reduced that of the pathogenic Ralstonia solanacearum SL1931. The expression of defence-related genes in the root and leaf after aphid feeding indicated that the above-ground aphid infestation elicited salicylic acid and jasmonic acid signalling throughout the whole plant. The findings of this study show that aphid feeding elicits plant resistance responses and attracts beneficial bacterial populations to help the plant cope with subsequent pathogen attacks.

  9. Comparative Radiosensitivity of Pathogenic Bacteria and Viruses

    International Nuclear Information System (INIS)

    Ghys, R.; Vandergoten, R.; Paquette, J.-C.; Fredette, V.; Plante, C.; Pavilanis, V.; Gilker, J.-C.

    1967-01-01

    The authors exposed to gamma rays from a MCo source (''Gammacell 220'' from Atomic Energy of Canada, Ltd.) various pathogenic micro-organisms: a slow-growing aerobic bacterium (Mycobacterium tuberculosis, 10 varieties of the strain B. C. G.), a fast-growing anaerobic bacterium (Clostridium perfringens, strain SWG-121) and 4 strains of influenza virus (2 from group A and 2 from group B). In the case of B. C. G., an LD 90 of 29 ± 1 kR is reported for bacilli irradiated immediately before subculture and subsequently cultivated for at most 14 days. If the microbes are cultivated for 28 days, the yield from cultures after exposures of up to 50 kR is at least equal to that of control specimens; it then decreases rapidly, and a dose of 140 kR inhibits bacterial growth completely. It is reported that the LD 90 of the strain of Cl. perfringens used in the study is very much dependent on die culture conditions and die conditions under which die microbe growth measurements are made; 24 h after irradiation it is at least 1 MR. Although no spores are seen in the microscope, this would seem to demonstrate the presence in the cultures of extremely radioresistant sporulated individuals. Group A influenza viruses are found to be more radioresistant than those of group B. The LD 90 of relatively low radiation doses varies between 75 and 100 kR, and is higher if irradiation is performed at -78.5°C. It is very difficult to inactivate the last virus particles; multiplicity reactivation seems to occur in certain experimental conditions. Haemagglutinant activity does not vary, even after die highest exposures used (4 MR). Two important practical conclusions are drawn: (1) The use of a single dose (e. g. 2.5 Mrad) for radiosterilization gives an exposure which is unnecessarily high in some cases and insufficient in others, and (2) Selective radiosterilization is sometimes possible: the viability of a micro-organism used, for example, to produce a vaccine may not be

  10. Raft-like membrane domains in pathogenic microorganisms.

    Science.gov (United States)

    Farnoud, Amir M; Toledo, Alvaro M; Konopka, James B; Del Poeta, Maurizio; London, Erwin

    2015-01-01

    The lipid bilayer of the plasma membrane is thought to be compartmentalized by the presence of lipid-protein microdomains. In eukaryotic cells, microdomains composed of sterols and sphingolipids, commonly known as lipid rafts, are believed to exist, and reports on the presence of sterol- or protein-mediated microdomains in bacterial cell membranes are also appearing. Despite increasing attention, little is known about microdomains in the plasma membrane of pathogenic microorganisms. This review attempts to provide an overview of the current state of knowledge of lipid rafts in pathogenic fungi and bacteria. The current literature on characterization of microdomains in pathogens is reviewed, and their potential role in growth, pathogenesis, and drug resistance is discussed. Better insight into the structure and function of membrane microdomains in pathogenic microorganisms might lead to a better understanding of their pathogenesis and development of raft-mediated approaches for therapy. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Capturing the dynamics of pathogens with many strains

    DEFF Research Database (Denmark)

    Kucharski, Adam; Andreasen, Viggo; Gog, Julia

    2016-01-01

    Pathogens that consist of multiple antigenic variants are a serious public health concern. These infections, which include dengue virus, influenza and malaria, generate substantial morbidity and mortality. However, there are considerable theoretical challenges involved in modelling such infection...

  12. Phytohormone mediation of interactions between herbivores and plant pathogens

    NARCIS (Netherlands)

    Lazebnik, J.; Frago, E.; Dicke, M.; Loon, van J.J.A.

    2014-01-01

    Induced plant defenses against either pathogens or herbivore attackers are regulated by phytohormones. These phytohormones are increasingly recognized as important mediators of interactions between organisms associated with plants. In this review, we discuss the role of plant defense hormones in

  13. Pathogens and host immunity in the ancient human oral cavity

    Science.gov (United States)

    Warinner, Christina; Matias Rodrigues, João F.; Vyas, Rounak; Trachsel, Christian; Shved, Natallia; Grossmann, Jonas; Radini, Anita; Hancock, Y.; Tito, Raul Y.; Fiddyment, Sarah; Speller, Camilla; Hendy, Jessica; Charlton, Sophy; Luder, Hans Ulrich; Salazar-García, Domingo C.; Eppler, Elisabeth; Seiler, Roger; Hansen, Lars; Samaniego Castruita, José Alfredo; Barkow-Oesterreicher, Simon; Teoh, Kai Yik; Kelstrup, Christian; Olsen, Jesper V.; Nanni, Paolo; Kawai, Toshihisa; Willerslev, Eske; von Mering, Christian; Lewis, Cecil M.; Collins, Matthew J.; Gilbert, M. Thomas P.; Rühli, Frank; Cappellini, Enrico

    2014-01-01

    Calcified dental plaque (dental calculus) preserves for millennia and entraps biomolecules from all domains of life and viruses. We report the first high-resolution taxonomic and protein functional characterization of the ancient oral microbiome and demonstrate that the oral cavity has long served as a reservoir for bacteria implicated in both local and systemic disease. We characterize: (i) the ancient oral microbiome in a diseased state, (ii) 40 opportunistic pathogens, (iii) the first evidence of ancient human-associated putative antibiotic resistance genes, (iv) a genome reconstruction of the periodontal pathogen Tannerella forsythia, (v) 239 bacterial and 43 human proteins, allowing confirmation of a long-term association between host immune factors, “red-complex” pathogens, and periodontal disease, and (vi) DNA sequences matching dietary sources. Directly datable and nearly ubiquitous, dental calculus permits the simultaneous investigation of pathogen activity, host immunity, and diet, thereby extending the direct investigation of common diseases into the human evolutionary past. PMID:24562188

  14. Interactions between the microbiota and pathogenic bacteria in the gut.

    Science.gov (United States)

    Bäumler, Andreas J; Sperandio, Vanessa

    2016-07-07

    The microbiome has an important role in human health. Changes in the microbiota can confer resistance to or promote infection by pathogenic bacteria. Antibiotics have a profound impact on the microbiota that alters the nutritional landscape of the gut and can lead to the expansion of pathogenic populations. Pathogenic bacteria exploit microbiota-derived sources of carbon and nitrogen as nutrients and regulatory signals to promote their own growth and virulence. By eliciting inflammation, these bacteria alter the intestinal environment and use unique systems for respiration and metal acquisition to drive their expansion. Unravelling the interactions between the microbiota, the host and pathogenic bacteria will produce strategies for manipulating the microbiota against infectious diseases.

  15. Deoxyribonucleoside kinases activate nucleoside antibiotics in severely pathogenic bacteria

    DEFF Research Database (Denmark)

    Sandrini, Michael; Shannon, O.; Clausen, A.R.

    2007-01-01

    Common bacterial pathogens are becoming progressively more resistant to traditional antibiotics, representing a major public-health crisis. Therefore, there is a need for a variety of antibiotics with alternative modes of action. In our study, several nucleoside analogs were tested against pathog...... alternative for combating pathogenic bacteria.......Common bacterial pathogens are becoming progressively more resistant to traditional antibiotics, representing a major public-health crisis. Therefore, there is a need for a variety of antibiotics with alternative modes of action. In our study, several nucleoside analogs were tested against...... pathogenic staphylococci and streptococci. We show that pyrimidine-based nucleoside analogs, like 3'-azido-3'-deoxythymidine (AZT) and 2',2'-difluoro-2'deoxycytidine (gemcitabine), are specifically activated by the endogenous bacterial deoxyribonucleoside kinases, leading to cell death. Deoxyribonucleoside...

  16. Antimicrobial properties of tropical plants against 12 pathogenic ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-07-04

    Jul 4, 2008 ... varies depending on bacterial species and type of extract. The average ... more species of bacteria. The most ..... 12 types of food borne bacteria including pathogens. ... the production of human collagen I, a protein associated.

  17. Inflammasome/IL-1β Responses to Streptococcal Pathogens

    Directory of Open Access Journals (Sweden)

    Christopher N. LaRock

    2015-10-01

    Full Text Available Inflammation mediated by the inflammasome and the cytokine IL-1β are some of the earliest and most important alarms to infection. These pathways are responsive to the virulence factors that pathogens use to subvert immune processes, and thus are typically activated only by microbes with potential to cause severe disease. Among the most serious human infections are those caused by the pathogenic streptococci, in part because these species numerous strategies for immune evasion. Since the virulence factor armament of each pathogen is unique, the role of IL-1β and the pathways leading to its activation varies for each infection. This review summarizes the role of IL-1β during infections caused by streptococcal pathogens, with emphasis on emergent mechanisms and concepts countering paradigms determined for other organisms.

  18. Distribution of potential nosocomial pathogens in a hospital ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-10-20

    Oct 20, 2008 ... associated/acquired infections) are those infections that develop in a patient during ... nosocomial pathogens that cause infections can come either from ... aeruginosa is a regular cause of nosocomial pneumonia, urinary tract ...

  19. Genomewide analyses of pathogenic and regulatory T cells of NOD ...

    Indian Academy of Sciences (India)

    DANG SUN

    Two regulatory T cell clones (Tregs) were used in this study. Treg1 cells were clone-derived from the previously described. Keywords. methylation; cDNA microarray; type 1 diabetes; pathogenic T cells; .... Gender-specific differences in.

  20. Impact of electromagnetic field on the pathogenicity of selected ...

    African Journals Online (AJOL)

    Rhipicephalus decoloratus) to variable intensities of electromagnetic field for different periods of time was examined on their pathogenicity on tick. Some bacterial isolates from the macerate of tick cadavers were used in the infection of healthy engorged ...

  1. Association of the pitch canker pathogen Fusarium circinatum with ...

    African Journals Online (AJOL)

    Association of the pitch canker pathogen Fusarium circinatum with grass hosts in commercial pine production areas of South Africa. Cassandra L Swett, Bernice Porter, Gerda Fourie, Emma T Steenkamp, Thomas R Gordon, Michael J Wingfield ...

  2. Antibiotic resistance in bacterial pathogens causing meningitis in ...

    African Journals Online (AJOL)

    Antibiotic resistance in bacterial pathogens causing meningitis in children at Harare Central Hospital, Zimbabwe. M Gudza-Mugabe, R.T. Mavenyengwa, M.P. Mapingure, S Mtapuri-Zinyowera, A Tarupiwa, V.J. Robertson ...

  3. Conference Report: The 6th International Symposium on Waterborne Pathogens

    Data.gov (United States)

    U.S. Environmental Protection Agency — A review of current literature on the occurrence of waterborne pathogens in DW systems. This dataset is not publicly accessible because: I am using published data...

  4. Extracellular Proteome and Citrullinome of the Oral Pathogen Porphyromonas gingivalis

    NARCIS (Netherlands)

    Stobernack, Tim; Glasner, Corinna; Junker, Sabryna; Gabarrini, Giorgio; de Smit, Menke; de Jong, Anne; Otto, Andreas; Becher, Doerte; van Winkelhoff, Arie Jan; van Dijl, Jan Maarten

    2016-01-01

    Porphyromonas gingivalis is an oral pathogen associated with the inflammatory disease periodontitis. Periodontitis and P. gingivalis have been associated with rheumatoid arthritis. One of the hallmarks of rheumatoid arthritis is the loss of tolerance against citrullinated proteins. Citrullination is

  5. A possible tradeoff between developmental rate and pathogen ...

    Indian Academy of Sciences (India)

    related tradeoffs is that they are mediated via the conflict- ... Keywords. life-history evolution; tradeoff; development time; immune function; pathogen; Drosophila. Journal of Genetics .... This work was supported in parts by funds from Depart-.

  6. Detection of mastitis pathogens by analysis of volatile bacterial metabolites

    NARCIS (Netherlands)

    Hettinga, K.A.; Valenberg, van H.J.F.; Lam, T.J.G.M.; Hooijdonk, van A.C.M.

    2008-01-01

    The ability to detect mastitis pathogens based on their volatile metabolites was studied. Milk samples from cows with clinical mastitis, caused by Staphylococcus aureus, coagulase-negative staphylococci, Streptococcus uberis, Streptococcus dysgalactiae, and Escherichia coli were collected. In

  7. 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

  8. Exploring NAD+ metabolism in host-pathogen interactions.

    Science.gov (United States)

    Mesquita, Inês; Varela, Patrícia; Belinha, Ana; Gaifem, Joana; Laforge, Mireille; Vergnes, Baptiste; Estaquier, Jérôme; Silvestre, Ricardo

    2016-03-01

    Nicotinamide adenine dinucleotide (NAD(+)) is a vital molecule found in all living cells. NAD(+) intracellular levels are dictated by its synthesis, using the de novo and/or salvage pathway, and through its catabolic use as co-enzyme or co-substrate. The regulation of NAD(+) metabolism has proven to be an adequate drug target for several diseases, including cancer, neurodegenerative or inflammatory diseases. Increasing interest has been given to NAD(+) metabolism during innate and adaptive immune responses suggesting that its modulation could also be relevant during host-pathogen interactions. While the maintenance of NAD(+) homeostatic levels assures an adequate environment for host cell survival and proliferation, fluctuations in NAD(+) or biosynthetic precursors bioavailability have been described during host-pathogen interactions, which will interfere with pathogen persistence or clearance. Here, we review the double-edged sword of NAD(+) metabolism during host-pathogen interactions emphasizing its potential for treatment of infectious diseases.

  9. Circumscription of the anthracnose pathogens Colletotrichum lindemuthianum and C. nigrum

    NARCIS (Netherlands)

    Liu, F.; Cai, L.; Crous, P.W.; Damm, U.

    2013-01-01

    The anthracnose pathogen of common bean (Phaseolus vulgaris) is usually identified as Colletotrichum lindemuthianum, while anthracnose of potato (Solanum tuberosum), peppers (Capsicum annuum), tomato (S. lycopersicum) and several other crop plants is often attributed to C. coccodes. In order to

  10. Interactions between the microbiota and pathogenic bacteria in the gut

    Science.gov (United States)

    Bäumler, Andreas J.; Sperandio, Vanessa

    2016-01-01

    The microbiome has an important role in human health. Changes in the microbiota can confer resistance to or promote infection by pathogenic bacteria. Antibiotics have a profound impact on the microbiota that alters the nutritional landscape of the gut and can lead to the expansion of pathogenic populations. Pathogenic bacteria exploit microbiota-derived sources of carbon and nitrogen as nutrients and regulatory signals to promote their own growth and virulence. By eliciting inflammation, these bacteria alter the intestinal environment and use unique systems for respiration and metal acquisition to drive their expansion. Unravelling the interactions between the microbiota, the host and pathogenic bacteria will produce strategies for manipulating the microbiota against infectious diseases. PMID:27383983

  11. Sandpits as a reservoir of potentially pathogenic fungi for children

    Directory of Open Access Journals (Sweden)

    Anna Wójcik

    2016-09-01

    Potentially pathogenic fungi are present in the sand taken from sandpits in Łódź. This fact poses a significant threat to child health and therefore proper maintenance and periodic checking of sandpits are of great importance.

  12. 2 original article non-attenuation of highly pathogenic avian

    African Journals Online (AJOL)

    Dr Oboro VO

    AFRICAN JOURNAL OF CLINICAL AND EXPERIMENTAL MICROBIOLOGY JANUARY 2010. ISBN 1595-689X ... NON-ATTENUATION OF HIGHLY PATHOGENIC AVIAN INFLUENZA. H5N1 BY .... Diagnostic PCR was conducted to determine ...

  13. Pathogenic adaptations to host-derived antibacterial copper

    Science.gov (United States)

    Chaturvedi, Kaveri S.; Henderson, Jeffrey P.

    2014-01-01

    Recent findings suggest that both host and pathogen manipulate copper content in infected host niches during infections. In this review, we summarize recent developments that implicate copper resistance as an important determinant of bacterial fitness at the host-pathogen interface. An essential mammalian nutrient, copper cycles between copper (I) (Cu+) in its reduced form and copper (II) (Cu2+) in its oxidized form under physiologic conditions. Cu+ is significantly more bactericidal than Cu2+ due to its ability to freely penetrate bacterial membranes and inactivate intracellular iron-sulfur clusters. Copper ions can also catalyze reactive oxygen species (ROS) generation, which may further contribute to their toxicity. Transporters, chaperones, redox proteins, receptors and transcription factors and even siderophores affect copper accumulation and distribution in both pathogenic microbes and their human hosts. This review will briefly cover evidence for copper as a mammalian antibacterial effector, the possible reasons for this toxicity, and pathogenic resistance mechanisms directed against it. PMID:24551598

  14. Abundance of pollution indicator and pathogenic bacteria in Mumbai waters

    Digital Repository Service at National Institute of Oceanography (India)

    Ramaiah, N.; Kolhe, V.; Sadhasivan, A

    As a part of environmental assessment in the Mumbai Harbour region, where large numbers of ships either take in ballast from- or discharge their ballast, many groups of indicator and human pathogenic bacteria were quantified. Samples (water...

  15. Suppression of soilborne pathogens in mixed cropping systems

    NARCIS (Netherlands)

    Hiddink, G.A.

    2008-01-01

    Since the green revolution, agricultural production has increased tremendously due to synthetic fertilizers, chemical crop protectants and high yielding plant varieties. However, soilborne pathogens remain yield-limiting factors in agricultural production. Hardly any sustainable solutions are

  16. Safety and Waste Management for SAM Pathogen Methods

    Science.gov (United States)

    The General Safety and Waste Management page offers section-specific safety and waste management details for the pathogens included in EPA's Selected Analytical Methods for Environmental Remediation and Recovery (SAM).

  17. Genomic Analysis of Pathogenicity Determinants in Mycobacterium kansasii Type I

    KAUST Repository

    Guan, Qingtian

    2016-01-01

    Mycobacteria, a genus within Actinobacteria Phylum, are well known for two pathogens that cause human diseases: leprosy and tuberculosis. Other than the obligate human mycobacteria, there is a group of bacteria that are present in the environment

  18. Simulated Pathogen Concentrations in Locally-Collected Greywater and Wastewater

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset contains simulated pathogen concentrations in locally-collected greywater and wastewater. Each .zip file includes 21 .csv files, each containing 10,000...

  19. Spirochaetes as intestinal pathogens: Lessons from a Brachyspira genome

    Directory of Open Access Journals (Sweden)

    Hampson David J

    2009-05-01

    Full Text Available Abstract Anaerobic spirochaetes of the genus Brachyspira have long been known as important gut pathogens of pigs, but increasingly they are recognised as causing disease in birds and other animal species, including human beings. The genome sequence of the major swine pathogen Brachyspira hyodysenteriae was recently published, and this revealed extensive genome optimisation that leads to adaptation to the complex environment of the colon. The genome sequences of other pathogenic and non-pathogenic Brachyspira species are becoming available, and this data will help to reveal how these species have evolved and adapted to varied lifestyles in the large intestines of different species, and why some but not others can induce colitis and diarrhoea.

  20. Understanding the behavior of foodborne pathogens in the food chain

    DEFF Research Database (Denmark)

    Rantsiou, Kalliopi; Mataragas, Marios; Jespersen, Lene

    2011-01-01

    In recent years and with the significant advancements in instrumentation for molecular biology methods, the focus of food microbiologists, dealing with pathogenic microorganisms in foods, is shifting. Scientists specifically aim at elucidating the effect that the food composition, as well...

  1. Meiosis and Haploid Gametes in the Pathogen Trypanosoma brucei

    OpenAIRE

    Peacock, Lori; Bailey, Mick; Carrington, Mark; Gibson, Wendy

    2014-01-01

    Summary In eukaryote pathogens, sex is an important driving force in spreading genes for drug resistance, pathogenicity, and virulence [1]. For the parasitic trypanosomes that cause African sleeping sickness, mating occurs during transmission by the tsetse vector [2, 3] and involves meiosis [4], but haploid gametes have not yet been identified. Here, we show that meiosis is a normal part of development in the insect salivary glands for all subspecies of Trypanosoma brucei, including the human...

  2. Environmental Persistence Influences Infection Dynamics for a Butterfly Pathogen.

    Directory of Open Access Journals (Sweden)

    Dara A Satterfield

    Full Text Available Many pathogens, including those infecting insects, are transmitted via dormant stages shed into the environment, where they must persist until encountering a susceptible host. Understanding how abiotic conditions influence environmental persistence and how these factors influence pathogen spread are crucial for predicting patterns of infection risk. Here, we explored the consequences of environmental transmission for infection dynamics of a debilitating protozoan parasite (Ophryocystis elektroscirrha that infects monarch butterflies (Danaus plexippus. We first conducted an experiment to observe the persistence of protozoan spores exposed to natural conditions. Experimental results showed that, contrary to our expectations, pathogen doses maintained high infectivity even after 16 days in the environment, although pathogens did yield infections with lower parasite loads after environmental exposure. Because pathogen longevity exceeded the time span of our experiment, we developed a mechanistic model to better explore environmental persistence for this host-pathogen system. Model analysis showed that, in general, longer spore persistence led to higher infection prevalence and slightly smaller monarch population sizes. The model indicated that typical parasite doses shed onto milkweed plants must remain viable for a minimum of 3 weeks for prevalence to increase during the summer-breeding season, and for 11 weeks or longer to match levels of infection commonly reported from the wild, assuming moderate values for parasite shedding rate. Our findings showed that transmission stages of this butterfly pathogen are long-lived and indicated that this is a necessary condition for the protozoan to persist in local monarch populations. This study provides a modeling framework for future work examining the dynamics of an ecologically important pathogen in an iconic insect.

  3. Pathogen-Induced Defense Signaling and Signal Crosstalk in Arabidopsis

    OpenAIRE

    Kariola, Tarja

    2006-01-01

    Erwinia carotovora subsp. carotovora is a bacterial phytopathogen that causes soft rot in various agronomically important crop plants. A genetically specified resistance to E. carotovora has not been defined, and plant resistance to this pathogen is established through nonspecific activation of basal defense responses. This, together with the broad host range, makes this pathogen a good model for studying the activation of plant defenses. Production and secretion of plant cell wall-degrading ...

  4. Fate and transport of pathogens in lakes and reservoirs.

    Science.gov (United States)

    Brookes, Justin D; Antenucci, Jason; Hipsey, Matthew; Burch, Michael D; Ashbolt, Nicholas J; Ferguson, Christobel

    2004-07-01

    Outbreaks of water-borne disease via public water supplies continue to be reported in developed countries even though there is increased awareness of, and treatment for, pathogen contamination. Pathogen episodes in lakes and reservoirs are often associated with rain events, and the riverine inflow is considered to be major source of pathogens. Consequently, the behaviour of these inflows is of particular importance in determining pathogen transport and distribution. Inflows are controlled by their density relative to that of the lake, such that warm inflows will flow over the surface of the lake as a buoyant surface flow and cold, dense inflows will sink beneath the lake water where they will flow along the bathymetry towards the deepest point. The fate of pathogens is determined by loss processes including settling and inactivation by temperature, UV and grazing. The general trend is for the insertion timescale to be shortest, followed by sedimentation losses and temperature inactivity. The fate of Cryptosporidium due to UV light inactivation can occur at opposite ends of the scale, depending on the location of the oocysts in the water column and the extinction coefficient for UV light. For this reason, the extinction coefficient for UV light appears to be a vitally important parameter for determining the risk of Cryptosporidium contamination. For risk assessment of pathogens in supply reservoirs, it is important to understand the role of hydrodynamics in determining the timescale of transport to the off-take relative to the timescale of inactivation. The characteristics of the riverine intrusion must also be considered when designing a sampling program for pathogens. A risk management framework is presented that accounts for pathogen fate and transport for reservoirs.

  5. Challenges in Fusarium, a Trans-Kingdom Pathogen.

    Science.gov (United States)

    van Diepeningen, Anne D; de Hoog, G Sybren

    2016-04-01

    Fusarium species are emerging human pathogens, next to being plant pathogens. Problems with Fusarium are in their diagnostics and in their difficult treatment, but also in what are actual Fusarium species or rather Fusarium-like species. In this issue Guevara-Suarez et al. (Mycopathologia. doi: 10.1007/s11046-016-9983-9 , 2016) characterized 89 isolates of Fusarium from Colombia showing especially lineages within the Fusarium solani and oxysporum species complexes to be responsible for onychomycosis.

  6. Ensuring privacy in the study of pathogen genetics

    OpenAIRE

    Mehta, Sanjay R.; Vinterbo, Staal A.; Little, Susan J.

    2014-01-01

    Rapid growth in the genetic sequencing of pathogens in recent years has led to the creation of large sequence databases. This aggregated sequence data can be very useful for tracking and predicting epidemics of infectious diseases. However, the balance between the potential public health benefit and the risk to personal privacy for individuals whose genetic data (personal or pathogen) are included in such work has been difficult to delineate, because neither the true benefit nor the actual ri...

  7. Extended Storage of Pathogen-Reduced Platelet Concentrates (PRECON)

    Science.gov (United States)

    2017-12-01

    transfusion. Our project proposes to determine the efficacy of using a pathogen inactivation technique (Mirasol) coupled with a platelet additive solution (PAS...technology, platelet additive solution, platelet recovery and survival, platelet storage, platelet storage solution, platelets, thrombocytopenia, transfusion...Platelets Report to 2017 Military Health System Research Symposium ……………………………………………………………….. 29 Extended Storage of Pathogen-Reduced Platelet Concentrates

  8. Sieve analysis using the number of infecting pathogens.

    Science.gov (United States)

    Follmann, Dean; Huang, Chiung-Yu

    2017-12-14

    Assessment of vaccine efficacy as a function of the similarity of the infecting pathogen to the vaccine is an important scientific goal. Characterization of pathogen strains for which vaccine efficacy is low can increase understanding of the vaccine's mechanism of action and offer targets for vaccine improvement. Traditional sieve analysis estimates differential vaccine efficacy using a single identifiable pathogen for each subject. The similarity between this single entity and the vaccine immunogen is quantified, for example, by exact match or number of mismatched amino acids. With new technology, we can now obtain the actual count of genetically distinct pathogens that infect an individual. Let F be the number of distinct features of a species of pathogen. We assume a log-linear model for the expected number of infecting pathogens with feature "f," f=1,…,F. The model can be used directly in studies with passive surveillance of infections where the count of each type of pathogen is recorded at the end of some interval, or active surveillance where the time of infection is known. For active surveillance, we additionally assume that a proportional intensity model applies to the time of potentially infectious exposures and derive product and weighted estimating equation (WEE) estimators for the regression parameters in the log-linear model. The WEE estimator explicitly allows for waning vaccine efficacy and time-varying distributions of pathogens. We give conditions where sieve parameters have a per-exposure interpretation under passive surveillance. We evaluate the methods by simulation and analyze a phase III trial of a malaria vaccine. © 2017, The International Biometric Society.

  9. Plant–pathogen interactions: what is proteomics telling us?

    OpenAIRE

    Mehta, Angela; Brasileiro, Ana C. M.; Souza, Djair S. L.; Romano, Eduardo; Campos, Magnólia A.; Grossi-de-Sa, Maria F.; Silva, Marília S.; Franco, Octávio L.; Fragoso, Rodrigo R.; Bevitori, Rosangela; Rocha, Thales L.

    2008-01-01

    Over the years, several studies have been performed to analyse plant–pathogen interactions. Recently, functional genomic strategies, including proteomics and transcriptomics, have contributed to the effort of defining gene and protein function and expression profiles. Using these ‘omic’ approaches, pathogenicity- and defence-related genes and proteins expressed during phytopathogen infections have been identified and enormous datasets have been accumulated. However, the unde...

  10. The wild life of tick-borne pathogens

    OpenAIRE

    Hofmeester, Tim R.

    2016-01-01

    Diseases that are transmitted by arthropod vectors from animal hosts to humans – so called zoonotic vector-borne diseases – have increased in incidence in the last decades. In North America and Europe, tick-borne pathogens cause the majority of vector-borne diseases, including Lyme borreliosis and tick-borne encephalitis. The pathogens causing these diseases are transmitted by tick species within the Ixodes ricinus complex. These are generalist ticks that have a multi-year lifecycle with thre...

  11. Photodynamic action on some pathogenic microorganisms of oral cavity

    Science.gov (United States)

    Ovchinnikov, Ilya S.; Tuchin, Valery V.

    2001-10-01

    The work is devoted to an analysis of pre-clinical and clinical experiments on photodynamic action of HeNe laser radiation in aggregate with a cation thiazinium dye Methylene Blue (MB) on a mix of pathogenic and conditionally pathogenic aerobic bacteria being activators of pyoinflammatory diseases of oral cavity. Concentration of photosensitizes at which there is no own bactericidal influence on dying microflora, and parameters of influence at which the efficiency of irradiated microflora defeat reaches 99 % are determined.

  12. BIOLOGICAL CONTROL OF WEEDS BY MEANS OF PLANT PATHOGENS

    OpenAIRE

    Marija Ravlić; Renata Baličević

    2014-01-01

    Biological control is the use of live beneficial organisms and products of their metabolism in the pests control. Plant pathogens can be used for weed control in three different ways: as classical, conservation and augmentative (inoculative and inundated) biological control. Inundated biological control involves the use of bioherbicides (mycoherbicides) or artificial breeding of pathogens and application in specific stages of crops and weeds. Biological control of weeds can be used where chem...

  13. Pathogenicity and Transmission of H5 and H7 Highly Pathogenic Avian Influenza Viruses in Mallards

    Science.gov (United States)

    Costa-Hurtado, Mar; Shepherd, Eric; DeJesus, Eric; Smith, Diane; Spackman, Erica; Kapczynski, Darrell R.; Suarez, David L.; Stallknecht, David E.; Swayne, David E.

    2016-01-01

    ABSTRACT Wild aquatic birds have been associated with the intercontinental spread of H5 subtype highly pathogenic avian influenza (HPAI) viruses of the A/goose/Guangdong/1/96 (Gs/GD) lineage during 2005, 2010, and 2014, but dispersion by wild waterfowl has not been implicated with spread of other HPAI viruses. To better understand why Gs/GD H5 HPAI viruses infect and transmit more efficiently in waterfowl than other HPAI viruses, groups of mallard ducks were challenged with one of 14 different H5 and H7 HPAI viruses, including a Gs/GD lineage H5N1 (clade 2.2) virus from Mongolia, part of the 2005 dispersion, and the H5N8 and H5N2 index HPAI viruses (clade 2.3.4.4) from the United States, part of the 2014 dispersion. All virus-inoculated ducks and contact exposed ducks became infected and shed moderate to high titers of the viruses, with the exception that mallards were resistant to Ck/Pennsylvania/83 and Ck/Queretaro/95 H5N2 HPAI virus infection. Clinical signs were only observed in ducks challenged with the H5N1 2005 virus, which all died, and with the H5N8 and H5N2 2014 viruses, which had decreased weight gain and fever. These three viruses were also shed in higher titers by the ducks, which could facilitate virus transmission and spread. This study highlights the possible role of wild waterfowl in the spread of HPAI viruses. IMPORTANCE The spread of H5 subtype highly pathogenic avian influenza (HPAI) viruses of the Gs/GD lineage by migratory waterfowl is a serious concern for animal and public health. H5 and H7 HPAI viruses are considered to be adapted to gallinaceous species (chickens, turkeys, quail, etc.) and less likely to infect and transmit in wild ducks. In order to understand why this is different with certain Gs/GD lineage H5 HPAI viruses, we compared the pathogenicity and transmission of several H5 and H7 HPAI viruses from previous poultry outbreaks to Gs/GD lineage H5 viruses, including H5N1 (clade 2.2), H5N8 and H5N2 (clade 2.3.4.4) viruses, in

  14. Comparative genomics reveals mobile pathogenicity chromosomes in Fusarium

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Li Jun; van der Does, H. C.; Borkovich, Katherine A.; Coleman, Jeffrey J.; Daboussi, Marie-Jose; Di Pietro, Antonio; Dufresne, Marie; Freitag, Michael; Grabherr, Manfred; Henrissat, Bernard; Houterman, Petra M.; Kang, Seogchan; Shim, Won-Bo; Wolochuk, Charles; Xie, Xiaohui; Xu, Jin Rong; Antoniw, John; Baker, Scott E.; Bluhm, Burton H.; Breakspear, Andrew; Brown, Daren W.; Butchko, Robert A.; Chapman, Sinead; Coulson, Richard; Coutinho, Pedro M.; Danchin, Etienne G.; Diener, Andrew; Gale, Liane R.; Gardiner, Donald; Goff, Steven; Hammond-Kossack, Kim; Hilburn, Karen; Hua-Van, Aurelie; Jonkers, Wilfried; Kazan, Kemal; Kodira, Chinnappa D.; Koehrsen, Michael; Kumar, Lokesh; Lee, Yong Hwan; Li, Liande; Manners, John M.; Miranda-Saavedra, Diego; Mukherjee, Mala; Park, Gyungsoon; Park, Jongsun; Park, Sook Young; Proctor, Robert H.; Regev, Aviv; Ruiz-Roldan, M. C.; Sain, Divya; Sakthikumar, Sharadha; Sykes, Sean; Schwartz, David C.; Turgeon, Barbara G.; Wapinski, Ilan; Yoder, Olen; Young, Sarah; Zeng, Qiandong; Zhou, Shiguo; Galagan, James; Cuomo, Christina A.; Kistler, H. Corby; Rep, Martijn

    2010-03-18

    Fusarium species are among the most important phytopathogenic and toxigenic fungi, having significant impact on crop production and animal health. Distinctively, members of the F. oxysporum species complex exhibit wide host range but discontinuously distributed host specificity, reflecting remarkable genetic adaptability. To understand the molecular underpinnings of diverse phenotypic traits and their evolution in Fusarium, we compared the genomes of three economically important and phylogenetically related, yet phenotypically diverse plant-pathogenic species, F. graminearum, F. verticillioides and F. oxysporum f. sp. lycopersici. Our analysis revealed greatly expanded lineage-specific (LS) genomic regions in F. oxysporum that include four entire chromosomes, accounting for more than one-quarter of the genome. LS regions are rich in transposons and genes with distinct evolutionary profiles but related to pathogenicity. Experimentally, we demonstrate for the first time the transfer of two LS chromosomes between strains of F. oxysporum, resulting in the conversion of a non-pathogenic strain into a pathogen. Transfer of LS chromosomes between otherwise genetically isolated strains explains the polyphyletic origin of host specificity and the emergence of new pathogenic lineages in the F. oxysporum species complex, putting the evolution of fungal pathogenicity into a new perspective.

  15. Evasion of Neutrophil Extracellular Traps by Respiratory Pathogens.

    Science.gov (United States)

    Storisteanu, Daniel M L; Pocock, Joanna M; Cowburn, Andrew S; Juss, Jatinder K; Nadesalingam, Angalee; Nizet, Victor; Chilvers, Edwin R

    2017-04-01

    The release of neutrophil extracellular traps (NETs) is a major immune mechanism intended to capture pathogens. These histone- and protease-coated DNA structures are released by neutrophils in response to a variety of stimuli, including respiratory pathogens, and have been identified in the airways of patients with respiratory infection, cystic fibrosis, acute lung injury, primary graft dysfunction, and chronic obstructive pulmonary disease. NET production has been demonstrated in the lungs of mice infected with Staphylococcus aureus, Klebsiella pneumoniae, and Aspergillus fumigatus. Since the discovery of NETs over a decade ago, evidence that "NET evasion" might act as an immune protection strategy among respiratory pathogens, including group A Streptococcus, Bordetella pertussis, and Haemophilus influenzae, has been growing, with the majority of these studies being published in the past 2 years. Evasion strategies fall into three main categories: inhibition of NET release by down-regulating host inflammatory responses; degradation of NETs using pathogen-derived DNases; and resistance to the microbicidal components of NETs, which involves a variety of mechanisms, including encapsulation. Hence, the evasion of NETs appears to be a widespread strategy to allow pathogen proliferation and dissemination, and is currently a topic of intense research interest. This article outlines the evidence supporting the three main strategies of NET evasion-inhibition, degradation, and resistance-with particular reference to common respiratory pathogens.

  16. The pathogenic persona of community-associated oral streptococci.

    Science.gov (United States)

    Whitmore, Sarah E; Lamont, Richard J

    2011-07-01

    The mitis group streptococci (MGS) are widespread in the oral cavity and are traditionally associated with oral health. However, these organisms have many attributes that contribute to the development of pathogenic oral communities. MGS adhere rapidly to saliva-coated tooth surfaces, thereby providing an attachment substratum for more overtly pathogenic organisms such as Porphyromonas gingivalis, and the two species assemble into heterotypic communities. Close physical association facilitates physiologic support, and pathogens such as Aggregatibacter actinomycetemcomitans display resource partitioning to favour carbon sources generated by streptococcal metabolism. MGS exchange information with community members through a number of interspecies signalling systems including AI-2 and contact dependent mechanisms. Signal transduction systems induced in P. gingivalis are based on protein dephosphorylation mediated by the tyrosine phosphatase Ltp1, and converge on a LuxR-family transcriptional regulator, CdhR. Phenotypic responses in P. gingivalis include regulation of hemin uptake systems and gingipain activity, processes that are intimately linked to the virulence of the organism. Furthermore, communities of S. gordonii with P. gingivalis or with A. actinomycetemcomitans are more pathogenic in animal models than the constituent species alone. We propose that MGS should be considered accessory pathogens, organisms whose pathogenic potential only becomes evident in the context of a heterotypic microbial community. © 2011 Blackwell Publishing Ltd.

  17. Protein Disulfide Isomerase and Host-Pathogen Interaction

    Directory of Open Access Journals (Sweden)

    Beatriz S. Stolf

    2011-01-01

    Full Text Available Reactive oxygen species (ROS production by immunological cells is known to cause damage to pathogens. Increasing evidence accumulated in the last decade has shown, however, that ROS (and redox signals functionally regulate different cellular pathways in the host-pathogen interaction. These especially affect (i pathogen entry through protein redox switches and redox modification (i.e., intra- and interdisulfide and cysteine oxidation and (ii phagocytic ROS production via Nox family NADPH oxidase enzyme and the control of phagolysosome function with key implications for antigen processing. The protein disulfide isomerase (PDI family of redox chaperones is closely involved in both processes and is also implicated in protein unfolding and trafficking across the endoplasmic reticulum (ER and towards the cytosol, a thiol-based redox locus for antigen processing. Here, we summarise examples of the cellular association of host PDI with different pathogens and explore the possible roles of pathogen PDIs in infection. A better understanding of these complex regulatory steps will provide insightful information on the redox role and coevolutional biological process, and assist the development of more specific therapeutic strategies in pathogen-mediated infections.

  18. Seed treatments to control seedborne fungal pathogens of vegetable crops.

    Science.gov (United States)

    Mancini, Valeria; Romanazzi, Gianfranco

    2014-06-01

    Vegetable crops are frequently infected by fungal pathogens, which can include seedborne fungi. In such cases, the pathogen is already present within or on the seed surface, and can thus cause seed rot and seedling damping-off. Treatment of vegetable seeds has been shown to prevent plant disease epidemics caused by seedborne fungal pathogens. Furthermore, seed treatments can be useful in reducing the amounts of pesticides required to manage a disease, because effective seed treatments can eliminate the need for foliar application of fungicides later in the season. Although the application of fungicides is almost always effective, their non-target environmental impact and the development of pathogen resistance have led to the search for alternative methods, especially in the past few years. Physical treatments that have already been used in the past and treatments with biopesticides, such as plant extracts, natural compounds and biocontrol agents, have proved to be effective in controlling seedborne pathogens. These have been applied alone or in combination, and they are widely used owing to their broad spectrum in terms of disease control and production yield. In this review, the effectiveness of different seed treatments against the main seedborne pathogens of some important vegetable crops is critically discussed. © 2013 Society of Chemical Industry.

  19. Entomopathogenic Fungi: New Insights into Host-Pathogen Interactions.

    Science.gov (United States)

    Butt, T M; Coates, C J; Dubovskiy, I M; Ratcliffe, N A

    2016-01-01

    Although many insects successfully live in dangerous environments exposed to diverse communities of microbes, they are often exploited and killed by specialist pathogens. Studies of host-pathogen interactions (HPI) provide valuable insights into the dynamics of the highly aggressive coevolutionary arms race between entomopathogenic fungi (EPF) and their arthropod hosts. The host defenses are designed to exclude the pathogen or mitigate the damage inflicted while the pathogen responds with immune evasion and utilization of host resources. EPF neutralize their immediate surroundings on the insect integument and benefit from the physiochemical properties of the cuticle and its compounds that exclude competing microbes. EPF also exhibit adaptations aimed at minimizing trauma that can be deleterious to both host and pathogen (eg, melanization of hemolymph), form narrow penetration pegs that alleviate host dehydration and produce blastospores that lack immunogenic sugars/enzymes but facilitate rapid assimilation of hemolymph nutrients. In response, insects deploy an extensive armory of hemocytes and macromolecules, such as lectins and phenoloxidase, that repel, immobilize, and kill EPF. New evidence suggests that immune bioactives work synergistically (eg, lysozyme with antimicrobial peptides) to combat infections. Some proteins, including transferrin and apolipophorin III, also demonstrate multifunctional properties, participating in metabolism, homeostasis, and pathogen recognition. This review discusses the molecular intricacies of these HPI, highlighting the interplay between immunity, stress management, and metabolism. Increased knowledge in this area could enhance the efficacy of EPF, ensuring their future in integrated pest management programs. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Annotating pathogenic non-coding variants in genic regions.

    Science.gov (United States)

    Gelfman, Sahar; Wang, Quanli; McSweeney, K Melodi; Ren, Zhong; La Carpia, Francesca; Halvorsen, Matt; Schoch, Kelly; Ratzon, Fanni; Heinzen, Erin L; Boland, Michael J; Petrovski, Slavé; Goldstein, David B

    2017-08-09

    Identifying the underlying causes of disease requires accurate interpretation of genetic variants. Current methods ineffectively capture pathogenic non-coding variants in genic regions, resulting in overlooking synonymous and intronic variants when searching for disease risk. Here we present the Transcript-inferred Pathogenicity (TraP) score, which uses sequence context alterations to reliably identify non-coding variation that causes disease. High TraP scores single out extremely rare variants with lower minor allele frequencies than missense variants. TraP accurately distinguishes known pathogenic and benign variants in synonymous (AUC = 0.88) and intronic (AUC = 0.83) public datasets, dismissing benign variants with exceptionally high specificity. TraP analysis of 843 exomes from epilepsy family trios identifies synonymous variants in known epilepsy genes, thus pinpointing risk factors of disease from non-coding sequence data. TraP outperforms leading methods in identifying non-coding variants that are pathogenic and is therefore a valuable tool for use in gene discovery and the interpretation of personal genomes.While non-coding synonymous and intronic variants are often not under strong selective constraint, they can be pathogenic through affecting splicing or transcription. Here, the authors develop a score that uses sequence context alterations to predict pathogenicity of synonymous and non-coding genetic variants, and provide a web server of pre-computed scores.