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Sample records for aged organophosphorus inhibited

  1. Lysophospholipase inhibition by organophosphorus toxicants

    International Nuclear Information System (INIS)

    Quistad, Gary B.; Casida, John E.

    2004-01-01

    Lysophospholipases (LysoPLAs) are a large family of enzymes for removing lysophospholipids from cell membranes. Potent inhibitors are needed to define the importance of LysoPLAs as targets for toxicants and potential therapeutics. This study considers organophosphorus (OP) inhibitors with emphasis on mouse brain total LysoPLA activity relative to the mipafox-sensitive neuropathy target esterase (NTE)-LysoPLA recently established as 17% of the total activity and important in the action of OP delayed toxicants. The most potent inhibitors of total LysoPLA in mouse brain are isopropyl dodecylphosphonofluoridate (also for LysoPLA of Vibrio bacteria), ethyl octylphosphonofluoridate (EOPF), and two alkyl-benzodioxaphosphorin 2-oxides (BDPOs)[(S)-octyl and dodecyl] (IC50 2-8 nM). OP inhibitors acting in vitro and in vivo differentiate a more sensitive portion but not a distinct NTE-LysoPLA compared with total LysoPLA activity. For 10 active inhibitors, NTE-LysoPLA is 17-fold more sensitive than total LysoPLA, but structure-activity comparisons give a good correlation (r 2 = 0.94) of IC50 values, suggesting active site structural similarity or identity. In mice 4 h after intraperitoneal treatment with discriminating doses, EOPF, tribufos (a plant defoliant), and dodecanesulfonyl fluoride inhibit 41-57% of the total brain LysoPLA and 85-99% of the NTE-LysoPLA activity. Total LysoPLA as well as NTE-LysoPLA is decreased in activity in Nte +/- -haploinsufficient mice compared to their Nte +/+ littermates. The lysolecithin level of spinal cord but not brain is elevated significantly following EOPF treatment (3 mg/kg), thereby focusing attention on localized rather than general alterations in lysophospholipid metabolism in OP-induced hyperactivity and toxicity

  2. QSAR for cholinesterase inhibition by organophosphorus esters and CNDO/2 calculations for organophosphorus ester hydrolysis

    Science.gov (United States)

    Johnson, H.; Kenley, R. A.; Rynard, C.; Golub, M. A.

    1985-01-01

    Quantitative structure-activity relationships were derived for acetyl- and butyrylcholinesterase inhibition by various organophosphorus esters. Bimolecular inhibition rate constants correlate well with hydrophobic substituent constants, and with the presence or absence of catonic groups on the inhibitor, but not with steric substituent constants. CNDO/2 calculations were performed on a separate set of organophosphorus esters, RR'P(O)X, where R and R' are alkyl and/or alkoxy groups and X is fluorine, chlorine or a phenoxy group. For each subset with the same X, the CNDO-derived net atomic charge at the central phosphorus atom in the ester correlates well with the alkaline hydrolysis rate constant. For the whole set of esters with different X, two equations were derived that relate either charge and leaving group steric bulk, or orbital energy and bond order to the hydrogen hydrolysis rate constant.

  3. Acute toxicity of organophosphorus compounds in guinea pigs is sex- and age-dependent and cannot be solely accounted for by acetylcholinesterase inhibition.

    Science.gov (United States)

    Fawcett, William P; Aracava, Yasco; Adler, Michael; Pereira, Edna F R; Albuquerque, Edson X

    2009-02-01

    This study was designed to test the hypothesis that the acute toxicity of the nerve agents S-[2-(diisopropylamino)ethyl]-O-ethyl methylphosphonothioate (VX), O-pinacolyl methylphosphonofluoridate (soman), and O-isopropyl methylphosphonofluoridate (sarin) in guinea pigs is age- and sex-dependent and cannot be fully accounted for by the irreversible inhibition of acetylcholinesterase (AChE). The subcutaneous doses of nerve agents needed to decrease 24-h survival of guinea pigs by 50% (LD(50) values) were estimated by probit analysis. In all animal groups, the rank order of LD(50) values was sarin > soman > VX. The LD(50) value of soman was not influenced by sex or age of the animals. In contrast, the LD(50) values of VX and sarin were lower in adult male than in age-matched female or younger guinea pigs. A colorimetric assay was used to determine the concentrations of nerve agents that inhibit in vitro 50% of AChE activity (IC(50) values) in guinea pig brain extracts, plasma, red blood cells, and whole blood. A positive correlation between LD(50) values and IC(50) values for AChE inhibition would support the hypothesis that AChE inhibition is a major determinant of the acute toxicity of the nerve agents. However, such a positive correlation was found only between LD(50) values and IC(50) values for AChE inhibition in brain extracts from neonatal and prepubertal guinea pigs. These results demonstrate for the first time that the lethal potencies of some nerve agents in guinea pigs are age- and sex-dependent. They also support the contention that mechanisms other than AChE inhibition contribute to the lethality of nerve agents.

  4. Acute Toxicity of Organophosphorus Compounds in Guinea Pigs Is Sex- and Age-Dependent and Cannot Be Solely Accounted for by Acetylcholinesterase Inhibition

    OpenAIRE

    Fawcett, William P.; Aracava, Yasco; Adler, Michael; Pereira, Edna F. R.; Albuquerque, Edson X.

    2008-01-01

    This study was designed to test the hypothesis that the acute toxicity of the nerve agents S-[2-(diisopropylamino)ethyl]-O-ethyl methylphosphonothioate (VX), O-pinacolyl methylphosphonofluoridate (soman), and O-isopropyl methylphosphonofluoridate (sarin) in guinea pigs is age- and sex-dependent and cannot be fully accounted for by the irreversible inhibition of acetylcholinesterase (AChE). The subcutaneous doses of nerve agents needed to decrease 24-h survival of guine...

  5. A Common Mechanism for Resistance to Oxime Reactivation of Acetylcholinesterase Inhibited by Organophosphorus Compounds

    Science.gov (United States)

    2013-01-01

    reactivated than AChE conjugates inhibited by the corresponding Rp enantiomers and this effect is enhanced as the size of the O-alkyl substituents of OP...Organophosphates and Carbamates, Butterworth & Heinemann , Oxford, 1992. pp. 555–577. [2] P. Taylor, Anticholinesterase agents, in: L.L. Brunton, J.S...application of the Hammett equation with the constants rph in the chemistry of organophosphorus compounds, Russ. Chem. Rev. 38 (1969) 795–811. [13

  6. Cognitive decline, mortality, and organophosphorus exposure in aging Mexican Americans.

    Science.gov (United States)

    Paul, Kimberly C; Ling, Chenxiao; Lee, Anne; To, Tu My; Cockburn, Myles; Haan, Mary; Ritz, Beate

    2018-01-01

    Cognitive impairment is a major health concern among older Mexican Americans, associated with significant morbidity and mortality, and may be influenced by environmental exposures. To investigate whether agricultural based ambient organophosphorus (OP) exposure influences 1) the rate of cognitive decline and mortality and 2) whether these associations are mediated through metabolic or inflammatory biomarkers. In a subset of older Mexican Americans from the Sacramento Area Latino Study on Aging (n = 430), who completed modified mini-mental state exams (3MSE) up to 7 times (1998-2007), we examined the relationship between estimated ambient OP exposures and cognitive decline (linear repeated measures model) and time to dementia or being cognitively impaired but not demented (CIND) and time to mortality (cox proportional hazards model). We then explored metabolic and inflammatory biomarkers as potential mediators of these relationships (additive hazards mediation). OP exposures at residential addresses were estimated with a geographic information system (GIS) based exposure assessment tool. Participants with high OP exposure in the five years prior to baseline experienced faster cognitive decline (β = 0.038, p = 0.02) and higher mortality over follow-up (HR = 1.91, 95% CI = 1.12, 3.26). The direct effect of OP exposure was estimated at 241 (95% CI = 27-455) additional deaths per 100,000 person-years, and the proportion mediated through the metabolic hormone adiponectin was estimated to be 4% 1.5-19.2). No other biomarkers were associated with OP exposure. Our study provides support for the involvement of OP pesticides in cognitive decline and mortality among older Mexican Americans, possibly through biologic pathways involving adiponectin. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Divergent effects of postmortem ambient temperature on organophosphorus- and carbamate-inhibited brain cholinesterase activity in birds

    Science.gov (United States)

    Hill, E.F.

    1989-01-01

    Time- and temperature-dependent postmortem changes in inhibited brain cholinesterase (ChE) activity may confound diagnosis of field poisoning of wildlife by anticholinesterase pesticide. Carbamate-inhibited ChE activity may return to normal within 1 to 2 days of exposure of intact carcass to moderate ambient temperature (18-32C). Organophosphorus-inhibited ChE activity becomes more depressed over the same time. Uninhibited ChE activity was resilient to above freezing temperature to 32C for 1 day and 25C for 3 days. Carbamate- and organophosphorus-inhibited ChE can be separated by incubation of homogenate for 1 hour at physiological temperatures; carbamylated ChE can be readily reactivated while phosphorylated ChE cannot.

  8. New Cinchona Oximes Evaluated as Reactivators of Acetylcholinesterase and Butyrylcholinesterase Inhibited by Organophosphorus Compounds

    Directory of Open Access Journals (Sweden)

    Maja Katalinić

    2017-07-01

    Full Text Available For the last six decades, researchers have been focused on finding efficient reactivators of organophosphorus compound (OP-inhibited acetylcholinesterase (AChE and butyrylcholinesterase (BChE. In this study, we have focused our research on a new oxime scaffold based on the Cinchona structure since it was proven to fit the cholinesterases active site and reversibly inhibit their activity. Three Cinchona oximes (C1, C2, and C3, derivatives of the 9-oxocinchonidine, were synthesized and investigated in reactivation of various OP-inhibited AChE and BChE. As the results showed, the tested oximes were more efficient in the reactivation of BChE and they reactivated enzyme activity to up to 70% with reactivation rates similar to known pyridinium oximes used as antidotes in medical practice today. Furthermore, the oximes showed selectivity towards binding to the BChE active site and the determined enzyme-oxime dissociation constants supported work on the future development of inhibitors in other targeted studies (e.g., in treatment of neurodegenerative disease. Also, we monitored the cytotoxic effect of Cinchona oximes on two cell lines Hep G2 and SH-SY5Y to determine the possible limits for in vivo application. The cytotoxicity results support future studies of these compounds as long as their biological activity is targeted in the lower micromolar range.

  9. An Age-Dependent Physiologically-Based Pharmacokinetic/Pharmacodynamic Model for the Organophosphorus Insecticide Chlorpyrifos in the Preweanling Rat

    Energy Technology Data Exchange (ETDEWEB)

    Timchalk, Chuck; Kousba, Ahmed A.; Poet, Torka S.

    2007-08-01

    Juvenile rats are more susceptible than adults to the acute toxicity of organophosphorus insecticides like chlorpyrifos (CPF). Age- and dose-dependent differences in metabolism may be responsible. Of importance is CYP450 activation and detoxification of CPF to chlorpyrifos-oxon (CPF-oxon) and trichloropyridinol (TCP), as well as B-esterase (cholinesterase; ChE) and A-esterase (PON-1) detoxification of CPF-oxon to TCP. In the current study, a modified physiologically based pharmacokinetic/pharmacodynamic (PBPK/PD) model incorporating age-dependent changes in CYP450, PON-1, and tissue ChE levels for rats was developed. In this model, age was used as a dependent function to estimate body weight which was then used to allometrically scale both metabolism and tissue ChE levels. Model simulations suggest that preweanling rats are particularly sensitive to CPF toxicity, with levels of CPF-oxon in blood and brain disproportionately increasing, relative to the response in adult rats. This age-dependent non-linear increase in CPF-oxon concentration may potentially result from the depletion of non-target B-esterases, and a lower PON-1 metabolic capacity in younger animals. These results indicate that the PBPK/PD model behaves consistently with the general understanding of CPF toxicity, pharmacokinetics and tissue ChE inhibition in neonatal and adult rats. Hence, this model represents an important starting point for developing a computational model to assess the neurotoxic potential of environmentally relevant organophosphate exposures in infants and children.

  10. Study of Serum Amylase and Serum Cholinesterase in Organophosphorus Poisoning

    Directory of Open Access Journals (Sweden)

    Sharan Badiger

    2016-04-01

    Full Text Available Background: Poisoning due to organophosphorus compounds is most commonly seen. Earlier plasma cholinesterase level was used to assess the severity of poisoning. Presently serum amylase is being recommended as a better indicator of severity. Aims and Objectives: To study plasma cholinesterase and serum amylase levels in acute organophosphorus and to correlate serum amylase levels with clinical severity and outcome. Material and Methods: A total of 80 patients in the study admitted to a tertiary care centre within 24 hours with a history of organophosphorus poisoning were included in study. Estimation of plasma cholinesterase and serum rd amylase was done at the time of admission, and on 3 th day and on 5 day. Results: Occurrence of organophosphorus poisoning was more common among age group 21-30 years and among males (57.5%. They were 25 (31.2% farmers, 23 (28.8% st u d e n ts, a n d 2 2 ( 2 7 . 5% h o u s ewi v e s. Monocrotophos (45.0% was commonly used compound. Mean value of plasma cholinesterase and serum amylase at admission are 3693 U/L, and 185.4 U/L. There was significant inhibition of plasma cholinesterase and elevation of serum amylase at th admission with return to normal values on 5 day. Conclusion: Plasma cholinesterase inhibition 200 U/L has been associated with poor prognosis and proneness to respiratory failure.

  11. Organophosphorus poisoning (acute).

    Science.gov (United States)

    Blain, Peter G

    2011-05-17

    Acetylcholinesterase inhibition by organophosphorus pesticides or organophosphate nerve agents can cause acute parasympathetic system dysfunction, muscle weakness, seizures, coma, and respiratory failure. Prognosis depends on the dose and relative toxicity of the specific compound, as well as pharmacokinetic factors. We conducted a systematic review and aimed to answer the following clinical question: What are the effects of treatments for acute organophosphorus poisoning? We searched: Medline, Embase, The Cochrane Library, and other important databases up to April 2010 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). We found 62 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. In this systematic review we present information relating to the effectiveness and safety of the following interventions: activated charcoal (single or multiple doses), alpha(2) adrenergic receptor agonists, atropine, benzodiazepines, butyrylcholinesterase replacement therapy, cathartics, extracorporeal clearance, gastric lavage, glycopyrronium bromide (glycopyrrolate), ipecacuanha (ipecac), magnesium sulphate, milk or other home remedy immediately after ingestion, N-methyl-D-aspartate receptor antagonists, organophosphorus hydrolases, oximes, removing contaminated clothes and washing the poisoned person, and sodium bicarbonate.

  12. Organophosphorus pesticide poisoning : cases and developments

    NARCIS (Netherlands)

    Aardema, H.; Ligtenberg, J. J. M.; Peters-Polman, O. M.; Tulleken, J. E.; Zijlstra, J. G.; Meertens, John H. J. M.

    Self-poisoning with organophosphate pesticides is a major health problem world-wide. Through the inhibition of acetylcholinesterase, organophosphorus poisoning is characterised by the clinical picture of acute cholinergic crisis. Other manifestations are the intermediate neurotoxic syndrome and

  13. Quantitative structure-activity analysis of acetylcholinesterase inhibition by oxono and thiono analogues of organophosphorus compounds. (Reannouncement with new availability information)

    Energy Technology Data Exchange (ETDEWEB)

    Maxwell, D.M.; Brecht, K.M.

    1992-02-01

    A comparison of the bimolecular rate constants (ki) for inhibition of electric eel acetylcholinesterase (AChE) by the oxono (i.e., P=O) and thiono (i.e., P=S) analogues of parathion, methylparathion, leptophos, fonofos, sarin, and soman revealed that the oxono/thiono ratios of ki values varied from 14 for soman to 1240 for parathion. Analysis of the relative importance of the dissociation equilibrium constant and the phosphorylation rate constant in producing this variation in ki values indicated that the oxono analogues had phosphorylation rate constant values that varied in a narrow range from 8- to 14-fold greater than their thiono counterparts, while the oxono/thiono ratios for dissociation constants varied widely from 1 for soman to 82 for fonofos. The lower affinities of thiono analogues for AChE probably resulted from differences in the hydrophobic binding of oxono and thiono analogues to the active site of AChE, inasmuch as the hydrophobicities (i.e., octanol/water partition coefficients) of thiono organophosphorus compounds were much greater than the hydrophobicities of their oxono analogues. Quantitative structure-activity analysis indicated that the hydrophobic effects of oxono and thiono moieties correlated with log ki for AChE inhibition to a greater extent (r2 = 0.79) than their electronic effects (r2 equal to or less than 0.48). These observations suggest that the differences in hydrophobicity of oxono and thiono analogues of organophosphorus compounds may be as important as their electronic differences in determining their effectiveness as AChE inhibitors. Acetylcholinesterase, soman (GD), structure-activity analysis inhibition, oxono analogues, thiono analogues.

  14. Inhibition of the prostaglandin EP2 receptor is neuroprotective and accelerates functional recovery in a rat model of organophosphorus induced status epilepticus

    Science.gov (United States)

    Rojas, Asheebo; Ganesh, Thota; Lelutiu, Nadia; Gueorguieva, Paoula; Dingledine, Raymond

    2015-01-01

    Exposure to high levels of organophosphorus compounds (OP) can induce status epilepticus (SE) in humans and rodents via acute cholinergic toxicity, leading to neurodegeneration and brain inflammation. Currently there is no treatment to combat the neuropathologies associated with OP exposure. We recently demonstrated that inhibition of the EP2 receptor for PGE2 reduces neuronal injury in mice following pilocarpine-induced SE. Here, we investigated the therapeutic effects of an EP2 inhibitor (TG6-10-1) in a rat model of SE using diisopropyl fluorophosphate (DFP). We tested the hypothesis that EP2 receptor inhibition initiated well after the onset of DFP-induced SE reduces the associated neuropathologies. Adult male Sprague-Dawley rats were injected with pyridostigmine bromide (0.1 mg/kg, sc) and atropine methylbromide (20 mg/kg, sc) followed by DFP (9.5 mg/kg, ip) to induce SE. DFP administration resulted in prolonged upregulation of COX-2. The rats were administered TG6-10-1 or vehicle (ip) at various time points relative to DFP exposure. Treatment with TG6-10-1 or vehicle did not alter the observed behavioral seizures, however six doses of TG6-10-1 starting 80-150 min after the onset of DFP-induced SE significantly reduced neurodegeneration in the hippocampus, blunted the inflammatory cytokine burst, reduced microglial activation and decreased weight loss in the days after status epilepticus. By contrast, astrogliosis was unaffected by EP2 inhibition 4 d after DFP. Transient treatments with the EP2 antagonist 1 h before DFP, or beginning 4 h after DFP, were ineffective. Delayed mortality, which was low (10%) after DFP, was unaffected by TG6-10-1. Thus, selective inhibition of the EP2 receptor within a time window that coincides with the induction of cyclooxygenase-2 by DFP is neuroprotective and accelerates functional recovery of rats. PMID:25656476

  15. Efficacious Oxime for Organophosphorus Poisoning: A Minireview ...

    African Journals Online (AJOL)

    Oximes are well known as acetylcholinesterase reactivators and are used in organophosphorus poisoning to reactivate inhibited acetylcholinesterase. Therapeutically available oximes, namely, pralidoxime (2-PAM), obidoxime, trimedoxime and Hagedorn oxime (HI-6), have no broad-spectrum activity against structurally ...

  16. In Search of an Effective in vivo Reactivator for Organophosphorus Nerve Agent-Inhibited Acetylcholinesterase in the Central Nervous System

    Science.gov (United States)

    2012-01-01

    nerve agents, such as sarin (GB), cyclosarin (GF), and VX, are potent inhibitors of the enzyme cholinesterase (ChE). Their toxic effects are due to...three nerve agents. Keywords: acetylcholinesterase; brain; cholinesterase inhibition; cholinesterase reactivation; cyclosarin; diacetylmonoxime...attributed, at least in part, to nuclophilic impedance [Ekstrom et al., 2006a; b; Hoskovcova et al., 2007]. Other AChE- inhibitors , such as soman, become

  17. A retrospective analysis of acute organophosphorus poisoning ...

    African Journals Online (AJOL)

    A retrospective analysis of acute organophosphorus poisoning cases admitted to the tertiary care teaching hospital in South India. ... Young adult males were more commonly involved than females (M:F 2.5:1). The mean age of the patients was 28 years (range 2-72 years, SD ± 14.3 years). Mean time to receive treatment ...

  18. A retrospective analysis of acute organophosphorus poisoning ...

    African Journals Online (AJOL)

    organophosphorus (OP) poisoning cases in a tertiary care hospital. Materials and ... In a pre-structured proforma, data regarding age, sex, time elapsed after intake, circumstances of poisoning, duration of hospitalization ... responsible for majority of self-attempted deaths ... cleansed with water at the time of admission.

  19. The organophosphorus extractants

    International Nuclear Information System (INIS)

    Zaoul, B.; Attou, M.; Azzouz, A.

    1989-07-01

    This work consists in a bibliographic review dealing with phosphorus and organophosphorus compounds chemistry and especially with the main extracting agents used in uranium ore treatment. In this context, a special interest is devoted to TBP, D 2 EHPA and TOPO. The content of this work is based on a large bibliography including cca. One hundred references related to many aspects concerning as well the nomenclature, the classification and the chemical structures of the organophosphorus compounds as synthesis methods, purification and analysis of the main extracting agents used in uranium extraction

  20. Contrasting neural effects of aging on proactive and reactive response inhibition

    NARCIS (Netherlands)

    Bloemendaal, Mirjam; Zandbelt, Bram; Wegman, Joost; Rest, van de O.; Cools, Roshan; Aarts, Esther

    2016-01-01

    Two distinct forms of response inhibition may underlie observed deficits in response inhibition in aging. We assessed whether age-related neurocognitive impairments in response inhibition reflect deficient reactive inhibition (outright stopping) or also deficient proactive inhibition

  1. Should we stop thinking about inhibition? Searching for individual and age differences in inhibition ability.

    Science.gov (United States)

    Rey-Mermet, Alodie; Gade, Miriam; Oberauer, Klaus

    2018-04-01

    Inhibition is often conceptualized as a unitary construct reflecting the ability to ignore and suppress irrelevant information. At the same time, it has been subdivided into inhibition of prepotent responses (i.e., the ability to stop dominant responses) and resistance to distracter interference (i.e., the ability to ignore distracting information). The present study investigated the unity and diversity of inhibition as a psychometric construct, and tested the hypothesis of an inhibition deficit in older age. We measured inhibition in young and old adults with 11 established laboratory tasks: antisaccade, stop-signal, color Stroop, number Stroop, arrow flanker, letter flanker, Simon, global-local, positive and negative compatibility tasks, and n-2 repetition costs in task switching. In both age groups, the inhibition measures from individual tasks had good reliabilities, but correlated only weakly among each other. Structural equation modeling identified a 2-factor model with factors for inhibition of prepotent responses and resistance to distracter interference. Older adults scored worse in the inhibition of prepotent response, but better in the resistance to distracter interference. However, the model had low explanatory power. Together, these findings call into question inhibition as a psychometric construct and the hypothesis of an inhibition deficit in older age. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  2. A step toward the reactivation of aged cholinesterases-crystal structure of ligands binding to aged human butyrylcholinesterase

    NARCIS (Netherlands)

    Wandhammer, M.; Koning, M. de; Grol, M. van; Loiodice, M.; Saurel, L.; Noort, D.; Goeldner, M.; Nachon, F.

    2013-01-01

    Organophosphorus nerve agents irreversibly inhibit cholinesterases. Phosphylation of the catalytic serine can be reversed by the mean of powerful nucleophiles like oximes. But the phosphyl adduct can undergo a rapid spontaneous reaction leading to an aged enzyme, i.e., a conjugated enzyme that is no

  3. Analogical reasoning and aging: the processing speed and inhibition hypothesis.

    Science.gov (United States)

    Bugaiska, Aurélia; Thibaut, Jean-Pierre

    2015-01-01

    This study was designed to investigate the effect of aging on analogical reasoning by manipulating the strength of semantic association (LowAssoc or HighAssoc) and the number of distracters' semantic analogies of the A:B::C:D type and to determine which factors might be responsible for the age-related differences on analogical reasoning by testing two different theoretical frameworks: the inhibition hypothesis and the speed mediation hypothesis. We compared young adults and two groups of aging people (old and old-old) with word analogies of the A:B::C:D format. Results indicate an age-related effect on analogical reasoning, this effect being greatest with LowAssoc analogies. It was not associated with the presence of semantic distractors. Moreover, the results show that the variance part of the analogy task due to age was mainly explained by processing speed (rather than by inhibition) in the case of old participants and by both processing speed and inhibition in the old-old group. These results are discussed in relation to current models of aging and their interaction with the processes involved in analogical reasoning.

  4. Memory, verbal fluency, and response inhibition in normal aging

    Directory of Open Access Journals (Sweden)

    Gaurav Thapliyal

    2016-01-01

    Full Text Available Background: The concepts of aging-related cognitive changes have appeared to be a major challenge in the society. In this context, the present study was planned to find out the functioning of aging population on different neurocognitive measures. Aims: The aim of the study was to find out the neurocognitive functioning, namely memory, verbal fluency, and response inhibition of normal aging population. Materials and Methods: Following purposive sampling technique, a total of 50 healthy subjects (30 males and 20 females in the age range of 60-70 years were recruited from Jaipur city of Rajasthan. Mini-mental state Examination, PGI memory scale, animal names test, and Stroop test were administered. Results: The findings reveal dysfunction in almost all the domains of memory, namely mental balance, attention and concentration, delayed recall, verbal retention for dissimilar pairs, visual retention and recognition, immediate recall, verbal retention for similar pairs, and visual retention. In domain of verbal fluency, all subjects gave low responses on the animal names test. In domain of response inhibition, all the subjects took less time in color test as compared to color word test on the Stroop task. Conclusions: Findings suggest that there are dysfunction in the area of memory, verbal fluency, and response inhibition in persons aged 60-70 years. However, recent and remote memory were found to be intact.

  5. Differences between organophosphorus insecticides in human self-poisoning: a prospective cohort study.

    Science.gov (United States)

    Eddleston, Michael; Eyer, Peter; Worek, Franz; Mohamed, Fahim; Senarathna, Lalith; von Meyer, Ludwig; Juszczak, Edmund; Hittarage, Ariyasena; Azhar, Shifa; Dissanayake, Wasantha; Sheriff, M H Rezvi; Szinicz, Ladislaus; Dawson, Andrew H; Buckley, Nick A

    Although more than 100 organophosphorus insecticides exist, organophosphorus poisoning is usually regarded as a single entity, distinguished only by the compound's lethal dose in animals. We aimed to determine whether the three most common organophosphorus insecticides used for self-poisoning in Sri Lanka differ in the clinical features and severity of poisoning they cause. We prospectively studied 802 patients with chlorpyrifos, dimethoate, or fenthion self-poisoning admitted to three hospitals. Blood cholinesterase activity and insecticide concentration were measured to determine the compound and the patients' response to insecticide and therapy. We recorded clinical outcomes for each patient. Compared with chlorpyrifos (35 of 439, 8.0%), the proportion dying was significantly higher with dimethoate (61 of 264, 23.1%, odds ratio [OR] 3.5, 95% CI 2.2-5.4) or fenthion (16 of 99, 16.2%, OR 2.2, 1.2-4.2), as was the proportion requiring endotracheal intubation (66 of 439 for chlorpyrifos, 15.0%; 93 of 264 for dimethoate, 35.2%, OR 3.1, 2.1-4.4; 31 of 99 for fenthion, 31.3%, 2.6, 1.6-4.2). Dimethoate-poisoned patients died sooner than those ingesting other pesticides and often from hypotensive shock. Fenthion poisoning initially caused few symptoms but many patients subsequently required intubation. Acetylcholinesterase inhibited by fenthion or dimethoate responded poorly to pralidoxime treatment compared with chlorpyrifos-inhibited acetylcholinesterase. Organophosphorus insecticide poisoning is not a single entity, with substantial variability in clinical course, response to oximes, and outcome. Animal toxicity does not predict human toxicity since, although chlorpyrifos is generally the most toxic in rats, it is least toxic in people. Each organophosphorus insecticide should be considered as an individual poison and, consequently, patients might benefit from management protocols developed for particular organophosphorus insecticides.

  6. In vitro study of the neuropathic potential of the organophosphorus compounds fenamiphos and profenofos: Comparison with mipafox and paraoxon.

    Science.gov (United States)

    Emerick, Guilherme L; Fernandes, Laís S; de Paula, Eloísa Silva; Barbosa, Fernando; dos Santos, Neife Aparecida Guinaim; dos Santos, Antonio Cardozo

    2015-08-01

    Organophosphorus-induced delayed neuropathy (OPIDN) is a central-peripheral distal axonopathy that develops 8-14 days after poisoning by a neuropathic organophosphorus compound (OP). Several OPs that caused OPIDN were withdrawn from the agricultural market due to induction of serious delayed effects. Therefore, the development of in vitro screenings able to differentiate neuropathic from non-neuropathic OPs is of crucial importance. Thus, the aim of this study was to evaluate the differences in the neurotoxic effects of mipafox (neuropathic OP) and paraoxon (non-neuropathic OP) in SH-SY5Y human neuroblastoma cells, using the inhibition and aging of neuropathy target esterase (NTE), inhibition of acetylcholinesterase (AChE), activation of calpain, neurite outgrowth, cytotoxicity and intracellular calcium as indicators. Additionally, the potential of fenamiphos and profenofos to cause acute and/or delayed effects was also evaluated. Mipafox had the lowest IC50 and induced the highest percentage of aging of NTE among the OPs evaluated. Only mipafox was able to cause calpain activation after 24 h of incubation. Concentrations of mipafox and fenamiphos which inhibited at least 70% of NTE were also able to reduce neurite outgrowth. Cytotoxicity was higher in non-neuropathic than in neuropathic OPs while the intracellular calcium levels were higher in neuropathic than in non-neuropathic OPs. In conclusion, the SH-SY5Y cellular model was selective to differentiate neuropathic from non-neuropathic OPs; fenamiphos, but not profenofos presented results compatible with the induction of OPIDN. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Method for purifying bidentate organophosphorus compounds

    International Nuclear Information System (INIS)

    Schulz, W.W.

    1977-01-01

    Bidentate organophosphorus compounds useful for extracting actinide elements from acidic nuclear waste solutions are purified of undesirable acidic impurities by contacting the compounds with ethylene glycol which preferentially extracts the impurities found in technical grade bidentate compounds

  8. Management of acute organophosphorus pesticide poisoning

    OpenAIRE

    Eddleston, Michael; Buckley, Nick A; Eyer, Peter; Dawson, Andrew H

    2008-01-01

    Summary Organophosphorus pesticide self-poisoning is an important clinical problem in rural regions of the developing world, and kills an estimated 200?000 people every year. Unintentional poisoning kills far fewer people but is a problem in places where highly toxic organophosphorus pesticides are available. Medical management is difficult, with case fatality generally more than 15%. We describe the limited evidence that can guide therapy and the factors that should be considered when design...

  9. A Longitudinal Investigation of Predictors of the Association Between Age 3 and Age 6 Behavioural Inhibition.

    Science.gov (United States)

    Johnson, Victoria C; Olino, Thomas M; Klein, Daniel N; Dyson, Margaret W; Bufferd, Sara J; Durbin, C Emily; Dougherty, Lea R; Hayden, Elizabeth P

    2016-08-01

    Children who exhibit elevated levels of the temperament trait behavioural inhibition (BI) across time may be at greatest risk for anxiety. However, little research has investigated the influence of other temperamental traits, particularly positive emotionality (PE), on the continuity of BI in childhood, nor whether parental overprotection influences associations between early and later child BI. To explore whether PE and overprotection shape associations between early and later BI, this longitudinal study of three-year-olds ( N = 446) followed up at age 6 included tasks tapping child temperament, and parental overprotection was assessed via interview ratings and parent-report. Lower levels of child PE and higher levels of caregiver overprotection at baseline predicted stronger associations between laboratory-assessed BI at ages 3 and 6. Findings elucidate influences shaping the developmental continuity of BI.

  10. of Several Organophosphorus Insecticide Metabolites

    Directory of Open Access Journals (Sweden)

    Russell L. Carr

    2015-01-01

    Full Text Available Paraoxonase (PON1 is a calcium dependent enzyme that is capable of hydrolyzing organophosphate anticholinesterases. PON1 activity is present in most mammals and previous research established that PON1 activity differs depending on the species. These studies mainly used the organophosphate substrate paraoxon, the active metabolite of the insecticide parathion. Using serum PON1 from different mammalian species, we compared the hydrolysis of paraoxon with the hydrolysis of the active metabolites (oxons of two additional organophosphorus insecticides, methyl parathion and chlorpyrifos. Paraoxon hydrolysis was greater than that of methyl paraoxon, but the level of activity between species displayed a similar pattern. Regardless of the species tested, the hydrolysis of chlorpyrifos-oxon was significantly greater than that of paraoxon or methyl paraoxon. These data indicate that chlorpyrifos-oxon is a better substrate for PON1 regardless of the species. The pattern of species differences in PON1 activity varied with the change in substrate to chlorpyrifos-oxon from paraoxon or methyl paraoxon. For example, the sex difference observed here and reported elsewhere in the literature for rat PON1 hydrolysis of paraoxon was not present when chlorpyrifos-oxon was the substrate.

  11. Efficacious Oxime for Organophosphorus Poisoning: A Minireview

    African Journals Online (AJOL)

    Erah

    Abstract. Oximes are well known as acetylcholinesterase reactivators and are used in ... activity against structurally different kinds of organophosphorus ... serious threat with regard to occupational .... choose an oxime for unknown OPC exposure. Secondly, there is a lack of .... oximes, and hence cannot pass the blood.

  12. Determination of selected organophosphorus pesticides using GC ...

    African Journals Online (AJOL)

    A reproducible analytical method utilising GC-MS is presented for the analysis of thirteen organophosphorus insecticides (OPs) often found in environmental aqueous samples. Extraction of filtered river and canal water (100 mL), fortified with the OPs, was conducted using solid-phase extraction and eluted with a variety of ...

  13. Organophosphorus insecticides: Toxic effects and bioanalytical tests for evaluating toxicity during degradation processes

    Directory of Open Access Journals (Sweden)

    Čolović Mirjana B.

    2013-01-01

    Full Text Available Organophosphorus insecticides have been the most applied group of insecticides for the last two decades. Their main toxic effects are related to irreversible inactivation of acetylcholinesterase (AChE. Actually, they covalently bind to serine OH group in the enzyme active site forming phosphorylated enzyme that cannot hydrolyze acetylcholine. Organophosphorus insecticides in the environment undergo the natural degradation pathway including mainly homogeneous and heterogeneous hydrolysis (especially at high pH generating non-inhibiting products. Additionally, thio organophosphates are easily oxidized by naturally present oxidants and UV light, forming more toxic and stable oxons. Thus, oxidative degradation procedures, generally referred as advanced oxidation processes (AOP, have been applied for their efficient removal from contaminated waters. The most applied bioassays to monitor the organophosphate toxicity i.e. the detoxification degree during AOP are Vibrio fischeri and AChE bioassays. Vibrio fischeri toxicity test exploits bioluminescence as the measure of luciferase activity of this marine bacterium, whereas AChE bioassay is based on AChE activity inhibition. Both bioanalytical techniques are rapid (several minutes, simple, sensitive and reproducible. Vibrio fischeri test seems to be a versatile indicator of toxic compounds generated in AOP for organophosphorus insecticides degradation. However, detection of neurotoxic AChE inhibitors, which can be formed in AOP of some organophosphates, requires AChE bioassays. Therefore, AChE toxicity test is more appropriate for monitoring the degradation processes of thio organophosphates, because more toxic oxo organophosphates might be formed and overlooked by Vibrio fischeri bioluminescence inhibition. In addition, during organophosphates removal by AOP, compounds with strong genotoxic potential may be formed, which cannot be detected by standard toxicity tests. For this reason, determination of

  14. Biochemical Markers for Exposure to Low Doses of Organophosphorus Insecticides

    National Research Council Canada - National Science Library

    Lockridge, Oksana

    2003-01-01

    Though acetylcholinesterase is the primary target of organophosphorus toxicants, our finding that acetylcholinesterase knockout mice are supersensitive to the lethal effects of VX, DFP, chlorpyrifos...

  15. Biochemical Markers for Exposure to Low Doses of Organophosphorus Insecticides

    National Research Council Canada - National Science Library

    Lockridge, Oksana

    2004-01-01

    Though acetylcholinesterase is the primary target of organophosphorus toxicants, our finding that acetylcholinesterase knockout mice are supersensitive to the lethal effects of VX, DFP, chlorpyrifos...

  16. Biochemical Markers for Exposure to Low Doses of Organophosphorus Insecticides

    National Research Council Canada - National Science Library

    Lockridge, Oksana

    2002-01-01

    Though acetyicholinesterase is the primary target of organophosphorus toxicants, our finding that acetyicholinesterase knockout mice are supersensitive to the lethal effects of VX, DFP, chlorpyrifos...

  17. Peer Exclusion Is Linked to Inhibition with Familiar but Not Unfamiliar Peers at Two Years of Age

    Science.gov (United States)

    Gazelle, Heidi; Faldowski, Richard A.

    2014-01-01

    This study examined the extent that inhibition among familiar peers was related to inhibition among unfamiliar peers versus exclusion by familiar peers at 2?years of age. Peer inhibition at 2?years of age was assessed by both mothers and teachers on versions of the Behavioral Inhibition Questionnaire and the Preschool Play Behavior Scale (N?=?141…

  18. Different approaches to acute organophosphorus poison treatment.

    Science.gov (United States)

    Nurulain, Syed Muhammad

    2012-07-01

    Organophosphorus compounds (OPCs) have a wide variety of applications and are a serious threat for self-poisoning, unintentional misuse, terrorist attack, occupational hazard and warfare attack. The present standard treatment has been reported to be unsatisfactory. Many novel approaches are being used and tested for acute organophosphorus (OP) poison treatment. The bioscavenger concept captured high attention among the scientific community during the last few decades. Other approaches like alkalinisation of blood plasma/serum and use of weak inhibitors against strong inhibitors, though it showed promising results, did not get such wide attention. The introduction of a novel broad-spectrum oxime has also been in focus. In this mini-review, an update of the overview of four different approaches has been discussed. The standard therapy that is atropine+oxime+benzodiazepine along with supportive measures will continue to be the best option with only the replacement of a single oxime to improve its broad-spectrum efficacy.

  19. Management of acute organophosphorus pesticide poisoning.

    Science.gov (United States)

    Eddleston, Michael; Buckley, Nick A; Eyer, Peter; Dawson, Andrew H

    2008-02-16

    Organophosphorus pesticide self-poisoning is an important clinical problem in rural regions of the developing world, and kills an estimated 200,000 people every year. Unintentional poisoning kills far fewer people but is a problem in places where highly toxic organophosphorus pesticides are available. Medical management is difficult, with case fatality generally more than 15%. We describe the limited evidence that can guide therapy and the factors that should be considered when designing further clinical studies. 50 years after first use, we still do not know how the core treatments--atropine, oximes, and diazepam--should best be given. Important constraints in the collection of useful data have included the late recognition of great variability in activity and action of the individual pesticides, and the care needed cholinesterase assays for results to be comparable between studies. However, consensus suggests that early resuscitation with atropine, oxygen, respiratory support, and fluids is needed to improve oxygen delivery to tissues. The role of oximes is not completely clear; they might benefit only patients poisoned by specific pesticides or patients with moderate poisoning. Small studies suggest benefit from new treatments such as magnesium sulphate, but much larger trials are needed. Gastric lavage could have a role but should only be undertaken once the patient is stable. Randomised controlled trials are underway in rural Asia to assess the effectiveness of these therapies. However, some organophosphorus pesticides might prove very difficult to treat with current therapies, such that bans on particular pesticides could be the only method to substantially reduce the case fatality after poisoning. Improved medical management of organophosphorus poisoning should result in a reduction in worldwide deaths from suicide.

  20. Propeptide-mediated inhibition of myostatin increases muscle mass through inhibiting proteolytic pathways in aged mice.

    Science.gov (United States)

    Collins-Hooper, Henry; Sartori, Roberta; Macharia, Raymond; Visanuvimol, Korntip; Foster, Keith; Matsakas, Antonios; Flasskamp, Hannah; Ray, Steve; Dash, Philip R; Sandri, Marco; Patel, Ketan

    2014-09-01

    Mammalian aging is accompanied by a progressive loss of skeletal muscle, a process called sarcopenia. Myostatin, a secreted member of the transforming growth factor-β family of signaling molecules, has been shown to be a potent inhibitor of muscle growth. Here, we examined whether muscle growth could be promoted in aged animals by antagonizing the activity of myostatin through the neutralizing activity of the myostatin propeptide. We show that a single injection of an AAV8 virus expressing the myostatin propeptide induced an increase in whole body weights and all muscles examined within 7 weeks of treatment. Our cellular studies demonstrate that muscle enlargement was due to selective fiber type hypertrophy, which was accompanied by a shift toward a glycolytic phenotype. Our molecular investigations elucidate the mechanism underpinning muscle hypertrophy by showing a decrease in the expression of key genes that control ubiquitin-mediated protein breakdown. Most importantly, we show that the hypertrophic muscle that develops as a consequence of myostatin propeptide in aged mice has normal contractile properties. We suggest that attenuating myostatin signaling could be a very attractive strategy to halt and possibly reverse age-related muscle loss. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. Analysis of organophosphorus pesticides using FT-NMR

    International Nuclear Information System (INIS)

    Miyata, Yoshihiko; Takahashi, Yoshikazu; Ando, Hiroaki

    1988-01-01

    A rapid and highly selective method of the identification of 23 kinds of organophosphorus pesticides was develop by using 31 P FT-NMR with 1 H complete decoupling method. Chemical shifts referenced by 85 % H 3 PO 4 were within -4 to 100 ppm, and there was no overlapping among the organophosphorus pesticides used in this experiment. (author)

  2. Aging Potentiates Lateral but Not Local Inhibition of Orientation Processing in Primary Visual Cortex

    Directory of Open Access Journals (Sweden)

    Zhengchun Wang

    2018-02-01

    Full Text Available Aging-related declines in vision can decrease well-being of the elderly. Concerning early sensory changes as in the primary visual cortex, physiological and behavioral reports seem contradictory. Neurophysiological studies on orientation tuning properties suggested that neuronal changes might come from decreased cortical local inhibition. However, behavioral results either showed no clear deficits in orientation processing in older adults, or proposed stronger surround suppression. Through psychophysical experiments and computational modeling, we resolved these discrepancies by suggesting that lateral inhibition increased in older adults while neuronal orientation tuning widths, related to local inhibition, stayed globally intact across age. We confirmed this later result by re-analyzing published neurophysiological data, which showed no systematic tuning width changes, but instead displayed a higher neuronal noise with aging. These results suggest a stronger lateral inhibition and mixed effects on local inhibition during aging, revealing a more complex picture of age-related effects in the central visual system than people previously thought.

  3. Age Differences in Text Processing: The Role of Working Memory, Inhibition, and Processing Speed

    OpenAIRE

    BORELLA ERIKA; GHISLETTA PAOLO; DE RIBAUPIERRE ANIK

    2011-01-01

    Objectives. Age-related changes in the efficiency of various general cognitive mechanisms have been evoked to account for age-related differences between young and older adults in text comprehension performance. Using structural equation modeling, we investigate the relationship between age, working memory (WM), inhibition-related mechanisms, processing speed, and text comprehension, focusing on surface and text-based levels of processing. Methods. Eighty-nine younger (M = 23.11 years) and 10...

  4. [ACTIVITY OF Ca2+,Mg(2+)-ATPase OF SARCOPLASMIC RETICULUM AND CONTRACTION STRENGTH OF THE FROG SKELETAL MUSCLES UNDER THE EFFECT OF ORGANOPHOSPHORUS INSECTICIDES].

    Science.gov (United States)

    Nozdrenko, D M; Korchinska, L V; Soroca, V M

    2015-01-01

    The results of an experimental study of organophosphorus insecticides, including pirimiphosmethyl, diazinon and chlorpyrifos caused a decline of the contraction properties in m. tibialis anterior fiber bundles of Rana temporaria, as well as sarcoplasmic reticulum Ca2+, Mg(2+)-ATPase enzymatic activity reduction are outlined in this paper. Concentration-dependent strengths response diminishing in isolated skeletal muscle fiber bundles as a result of non-cholinergic influence of organophosphorus insecticides were found. A decrease of Ca2+, Mg(2+)-ATPase enzymatic activity in sarcoplasmic reticulum was observed after administration of each insecticide. The most significant inhibition of this enzyme was observed when using chlorpyrifos.

  5. Oxidative stress accumulates in adipose tissue during aging and inhibits adipogenesis.

    Science.gov (United States)

    Findeisen, Hannes M; Pearson, Kevin J; Gizard, Florence; Zhao, Yue; Qing, Hua; Jones, Karrie L; Cohn, Dianne; Heywood, Elizabeth B; de Cabo, Rafael; Bruemmer, Dennis

    2011-04-14

    Aging constitutes a major independent risk factor for the development of type 2 diabetes and is accompanied by insulin resistance and adipose tissue dysfunction. One of the most important factors implicitly linked to aging and age-related chronic diseases is the accumulation of oxidative stress. However, the effect of increased oxidative stress on adipose tissue biology remains elusive. In this study, we demonstrate that aging in mice results in a loss of fat mass and the accumulation of oxidative stress in adipose tissue. In vitro, increased oxidative stress through glutathione depletion inhibits preadipocyte differentiation. This inhibition of adipogenesis is at least in part the result of reduced cell proliferation and an inhibition of G(1)→S-phase transition during the initial mitotic clonal expansion of the adipocyte differentiation process. While phosphorylation of the retinoblastoma protein (Rb) by cyclin/cdk complexes remains unaffected, oxidative stress decreases the expression of S-phase genes downstream of Rb. This silencing of S phase gene expression by increased oxidative stress is mediated through a transcriptional mechanism involving the inhibition of E2F recruitment and transactivation of its target promoters. Collectively, these data demonstrate a previously unrecognized role of oxidative stress in the regulation of adipogenesis which may contribute to age-associated adipose tissue dysfunction.

  6. Delaying aging and the aging-associated decline in protein homeostasis by inhibition of tryptophan degradation

    NARCIS (Netherlands)

    van der Goot, Annemieke T.; Zhu, Wentao; Vazquez-Manrique, Rafael P.; Seinstra, Renee I.; Dettmer, Katja; Michels, Helen; Farina, Francesca; Krijnen, Jasper; Melki, Ronald; Buijsman, Rogier C.; Silva, Mariana Ruiz; Thijssen, Karen L.; Kema, Ido P.; Neri, Christian; Oefner, Peter J.; Nollen, Ellen A. A.

    2012-01-01

    Toxicity of aggregation-prone proteins is thought to play an important role in aging and age-related neurological diseases like Parkinson and Alzheimer's diseases. Here, we identify tryptophan 2,3-dioxygenase (tdo-2), the first enzyme in the kynurenine pathway of tryptophan degradation, as a

  7. Blood cholinesterases as human biomarkers of organophosphorus pesticide exposure.

    Science.gov (United States)

    Nigg, H N; Knaak, J B

    2000-01-01

    The organophosphorus pesticides of this review were discovered in 1936 during the search for a replacement for nicotine for cockroach control. The basic biochemical characteristics of RBC AChE and BChE were determined in the 1940s. The mechanism of inhibition of both enzymes and other serine esterases was known in the 1940s and, in general, defined in the 1950s. In 1949, the death of a parathion mixer-loader dictated blood enzyme monitoring to prevent acute illness from organophosphorus pesticide intoxication. However, many of the chemical and biochemical steps for serine enzyme inhibition by OP compounds remain unknown today. The possible mechanisms of this inhibition are presented kinetically beginning with simple (by comparison) Michaelis-Menten substrate enzyme interaction kinetics. As complicated as the inhibition kinetics appear here, PBPK model kinetics will be more complex. The determination of inter- and intraindividual variation in RBC ChE and BChE was recognized early as critical knowledge for a blood esterase monitoring program. Because of the relatively constant production of RBCs, variation in RBC AChE was determined by about 1970. The source of plasma (or serum) BChE was shown to be the liver in the 1960s with the change in BChE phenotype to the donor in liver transplant patients. BChE activity was more variable than RBC AChE, and only in the 1990s have BChE individual variation questions been answered. We have reviewed the chemistry, metabolism, and toxicity of organophosphorus insecticides along with their inhibitory action toward tissue acetyl- and butyrylcholinesterases. On the basis of the review, a monitoring program for individuals mixing-loading and applying OP pesticides for commercial applicators was recommended. Approximately 41 OPs are currently registered for use by USEPA in the United States. Under agricultural working conditions, OPs primarily are absorbed through the skin. Liver P-450 isozymes catalyze the desulfurization of

  8. Chlorination of organophosphorus pesticides in natural waters

    Energy Technology Data Exchange (ETDEWEB)

    Acero, Juan L. [Departamento de Ingenieria Quimica y Energetica, Universidad de Extremadura, 06071 Badajoz (Spain)], E-mail: jlacero@unex.es; Benitez, F. Javier; Real, Francisco J.; Gonzalez, Manuel [Departamento de Ingenieria Quimica y Energetica, Universidad de Extremadura, 06071 Badajoz (Spain)

    2008-05-01

    Unknown second-order rate constants for the reactions of three organophosphorus pesticides (chlorpyrifos, chlorfenvinfos and diazinon) with chlorine were determined in the present study, and the influence of pH and temperature was established. It was found that an increase in the pH provides a negative effect on the pesticides degradation rates. Apparent second-order rate constants at 20 {sup o}C and pH 7 were determined to be 110.9, 0.004 and 191.6 M{sup -1} s{sup -1} for chlorpyrifos, chlorfenvinfos and diazinon, respectively. A higher reactivity of chlorine with the phosphorothioate group (chlorpyrifos and diazinon) than with the phosphate moiety (chlorfenvinfos) could explain these results. Intrinsic rate constant for the elementary reactions of chlorine species with chlorpyrifos and diazinon were also calculated, leading to the conclusion that the reaction between hypochlorous acid and the pesticide is predominant at neutral pH. The elimination of these pesticides in surface waters was also investigated. A chlorine dose of 2.5 mg L{sup -1} was enough to oxidize chlorpyrifos and diazinon almost completely, with a formation of trihalomethanes below the EU standard for drinking water. However, the removal of chlorfenvinfos was not appreciable. Therefore, chlorination is a feasible option for the removal of organophosphorus pesticides with phosphorothioate group during oxidation and disinfection processes, but not for the elimination of pesticides with phosphate moiety.

  9. Chlorination of organophosphorus pesticides in natural waters

    International Nuclear Information System (INIS)

    Acero, Juan L.; Benitez, F. Javier; Real, Francisco J.; Gonzalez, Manuel

    2008-01-01

    Unknown second-order rate constants for the reactions of three organophosphorus pesticides (chlorpyrifos, chlorfenvinfos and diazinon) with chlorine were determined in the present study, and the influence of pH and temperature was established. It was found that an increase in the pH provides a negative effect on the pesticides degradation rates. Apparent second-order rate constants at 20 o C and pH 7 were determined to be 110.9, 0.004 and 191.6 M -1 s -1 for chlorpyrifos, chlorfenvinfos and diazinon, respectively. A higher reactivity of chlorine with the phosphorothioate group (chlorpyrifos and diazinon) than with the phosphate moiety (chlorfenvinfos) could explain these results. Intrinsic rate constant for the elementary reactions of chlorine species with chlorpyrifos and diazinon were also calculated, leading to the conclusion that the reaction between hypochlorous acid and the pesticide is predominant at neutral pH. The elimination of these pesticides in surface waters was also investigated. A chlorine dose of 2.5 mg L -1 was enough to oxidize chlorpyrifos and diazinon almost completely, with a formation of trihalomethanes below the EU standard for drinking water. However, the removal of chlorfenvinfos was not appreciable. Therefore, chlorination is a feasible option for the removal of organophosphorus pesticides with phosphorothioate group during oxidation and disinfection processes, but not for the elimination of pesticides with phosphate moiety

  10. beta-Aminoalcohols as Potential Reactivators of Aged Sarin-/Soman-Inhibited Acetylcholinesterase

    Science.gov (United States)

    2017-02-08

    The calculations suggest that the designed b-aminoalcohol can selectively reactivate aged sarin-/soman-inhibited AChE. Fur - thermore, unlike existing...Kolossv#ry, K. F. Wong, F. Paesani, J. Vanicek, X. Wu, S. R. Brozell, T. Steinbrecher, H. Gohlke, L. Yang, C. Tan , J. Mongan, V. Hornak, G. Cui, D. H

  11. Delaying aging and the aging-associated decline in protein homeostasis by inhibition of tryptophan degradation

    Science.gov (United States)

    van der Goot, Annemieke T.; Zhu, Wentao; Vázquez-Manrique, Rafael P.; Seinstra, Renée I.; Dettmer, Katja; Michels, Helen; Farina, Francesca; Krijnen, Jasper; Melki, Ronald; Buijsman, Rogier C.; Ruiz Silva, Mariana; Thijssen, Karen L.; Kema, Ido P.; Neri, Christian; Oefner, Peter J.; Nollen, Ellen A. A.

    2012-01-01

    Toxicity of aggregation-prone proteins is thought to play an important role in aging and age-related neurological diseases like Parkinson and Alzheimer’s diseases. Here, we identify tryptophan 2,3-dioxygenase (tdo-2), the first enzyme in the kynurenine pathway of tryptophan degradation, as a metabolic regulator of age-related α-synuclein toxicity in a Caenorhabditis elegans model. Depletion of tdo-2 also suppresses toxicity of other heterologous aggregation-prone proteins, including amyloid-β and polyglutamine proteins, and endogenous metastable proteins that are sensors of normal protein homeostasis. This finding suggests that tdo-2 functions as a general regulator of protein homeostasis. Analysis of metabolite levels in C. elegans strains with mutations in enzymes that act downstream of tdo-2 indicates that this suppression of toxicity is independent of downstream metabolites in the kynurenine pathway. Depletion of tdo-2 increases tryptophan levels, and feeding worms with extra l-tryptophan also suppresses toxicity, suggesting that tdo-2 regulates proteotoxicity through tryptophan. Depletion of tdo-2 extends lifespan in these worms. Together, these results implicate tdo-2 as a metabolic switch of age-related protein homeostasis and lifespan. With TDO and Indoleamine 2,3-dioxygenase as evolutionarily conserved human orthologs of TDO-2, intervening with tryptophan metabolism may offer avenues to reducing proteotoxicity in aging and age-related diseases. PMID:22927396

  12. Detection of Organophosphorus Pesticides with Colorimetry and Computer Image Analysis.

    Science.gov (United States)

    Li, Yanjie; Hou, Changjun; Lei, Jincan; Deng, Bo; Huang, Jing; Yang, Mei

    2016-01-01

    Organophosphorus pesticides (OPs) represent a very important class of pesticides that are widely used in agriculture because of their relatively high-performance and moderate environmental persistence, hence the sensitive and specific detection of OPs is highly significant. Based on the inhibitory effect of acetylcholinesterase (AChE) induced by inhibitors, including OPs and carbamates, a colorimetric analysis was used for detection of OPs with computer image analysis of color density in CMYK (cyan, magenta, yellow and black) color space and non-linear modeling. The results showed that there was a gradually weakened trend of yellow intensity with the increase of the concentration of dichlorvos. The quantitative analysis of dichlorvos was achieved by Artificial Neural Network (ANN) modeling, and the results showed that the established model had a good predictive ability between training sets and predictive sets. Real cabbage samples containing dichlorvos were detected by colorimetry and gas chromatography (GC), respectively. The results showed that there was no significant difference between colorimetry and GC (P > 0.05). The experiments of accuracy, precision and repeatability revealed good performance for detection of OPs. AChE can also be inhibited by carbamates, and therefore this method has potential applications in real samples for OPs and carbamates because of high selectivity and sensitivity.

  13. Neurotoxicity in Preclinical Models of Occupational Exposure to Organophosphorus Compounds

    Science.gov (United States)

    Voorhees, Jaymie R.; Rohlman, Diane S.; Lein, Pamela J.; Pieper, Andrew A.

    2017-01-01

    Organophosphorus (OPs) compounds are widely used as insecticides, plasticizers, and fuel additives. These compounds potently inhibit acetylcholinesterase (AChE), the enzyme that inactivates acetylcholine at neuronal synapses, and acute exposure to high OP levels can cause cholinergic crisis in humans and animals. Evidence further suggests that repeated exposure to lower OP levels insufficient to cause cholinergic crisis, frequently encountered in the occupational setting, also pose serious risks to people. For example, multiple epidemiological studies have identified associations between occupational OP exposure and neurodegenerative disease, psychiatric illness, and sensorimotor deficits. Rigorous scientific investigation of the basic science mechanisms underlying these epidemiological findings requires valid preclinical models in which tightly-regulated exposure paradigms can be correlated with neurotoxicity. Here, we review the experimental models of occupational OP exposure currently used in the field. We found that animal studies simulating occupational OP exposures do indeed show evidence of neurotoxicity, and that utilization of these models is helping illuminate the mechanisms underlying OP-induced neurological sequelae. Still, further work is necessary to evaluate exposure levels, protection methods, and treatment strategies, which taken together could serve to modify guidelines for improving workplace conditions globally. PMID:28149268

  14. Treatment Strategies for the NMDA Component of Organophosphorus Convulsions

    National Research Council Canada - National Science Library

    Peterson, Steven

    2003-01-01

    ...) induced status epilepticus (SE) used here as a model of organophosphorus nerve agents. The nonbarbiturate anesthetic propofol was found to induce significant anticonvulsant and neuroprotectant effects in Li-pilo SE...

  15. Plasma esterases in the tegu lizard Tupinambis merianae (Reptilia, Teiidae): impact of developmental stage, sex, and organophosphorus in vitro exposure.

    Science.gov (United States)

    Basso, Agustín; Attademo, Andrés M; Lajmanovich, Rafael C; Peltzer, Paola M; Junges, Celina; Cabagna, Mariana C; Fiorenza, Gabriela S; Sanchez-Hernandez, Juan Carlos

    2012-01-01

    In this study, we determined normal serum butyrylcholinesterase (BChE) and carboxylesterase (CbE) activities in Tupinambis merianae in order to obtain reference values for organophosphorus pesticide monitoring. Forty-two T. merianae individuals were grouped by sex and size to identify potential differences in their enzyme levels to allow for proper representation of normal values for females, males, juveniles, and hatchlings. Mean CbE was determined using two model substrates: alpha-naphtylacetate (α-NA) and p-nitrophenyl valerate (4-NPV). BChE and CbE sensitivity to malaoxon (Mx) was also evaluated as well as the possibility of BChE reactivation with pyridine-2-aldoxime methochloride (2-PAM). Mean adult females' BChE was significantly higher than adult males, juveniles, and hatchlings. No significant differences were found between groups regarding CbE. CbE (4-NPV) activity showed slightly negative correlation with lizard snout-vent length, while BChE and CbE (α-NA) showed no correlation with body size. Apparent IC(50) values for BChE and CbE (α-NA) suggested different sensitivities among groups. CbE (4-NPV) could not be inhibited. All Mx-inhibited groups treated with 2-PAM in a final concentration of 2.8 mM showed clear signs of reactivation. In conclusion, the results demonstrate that (1) plasma esterase activity did not vary with age and sex, except for BChE activity, and (2) because biological and environmental variables could be confounding factors in the response of plasma cholinesterases, complementary biomarkers like CbE inhibition and oxime-induced reactivation of esterases are strongly recommended.

  16. [Decontamination of organophosphorus compounds: Towards new alternatives].

    Science.gov (United States)

    Poirier, L; Jacquet, P; Elias, M; Daudé, D; Chabrière, E

    2017-05-01

    Organophosphorus coumpounds (OP) are toxic chemicals mainly used for agricultural purpose such as insecticides and were also developed and used as warfare nerve agents. OP are inhibitors of acetylcholinesterase, a key enzyme involved in the regulation of the central nervous system. Chemical, physical and biological approaches have been considered to decontaminate OP. This review summarizes the current and emerging strategies that are investigated to tackle this issue with a special emphasis on enzymatic remediation methods. During the last decade, many studies have been dedicated to the development of biocatalysts for OP removal. Among these, recent reports have pointed out the promising enzyme SsoPox isolated from the archaea Sulfolobus solfataricus. Considering both its intrinsic stability and activity, this hyperthermostable enzyme is highly appealing for the decontamination of OP. Copyright © 2017 Académie Nationale de Pharmacie. All rights reserved.

  17. ANALYSIS OF ORGANOPHOSPHORUS POISONING, AT TERTIARY CARE HOSPITAL: A REPORT

    Directory of Open Access Journals (Sweden)

    Shakuntala

    2015-01-01

    Full Text Available BACKGROUND: Organophosphorus (OP compounds are the most common suicidal poison in developing countries and mortality continues to be high. The present study was aimed to know the pattern and outcome of the OP poisoning. METHODOLOGY: A record based retrospective study from January 2013 - December 2013 was Conducted in a tertiary care hospital and data regarding age, gender, domicile, type of poison, manner of poisoning, seasonal trends, marital status, motive behind poisoning , socio - economic status and outcome was collected in a pre - structured Performa. All data were documented, analyzed and interpreted as per the laid down protocol. RESULTS : out of total 1575 cases of OP compound poisoning, 71.73% (1130 were male, 28.27% (445 were female, 34.6% were in the age group 21 - 30 years, 70.95% were of low socio - economic status, Occupation wise agricultural workers were on top of the list (70.07%, The commonest (93.78% motive behind poisoning was suicidal in both males and females, Financial problem was one of the commonest (51.22% reasons of poisoning. The mortality rate in our study was 13.47%. CONCLUSION : Y oung and adult males of Low socio - economic class, rural, both literate and illiterate agriculturists commonly abuse this substance to commit suicide

  18. Comparison of oxime reactivation and aging of nerve agent-inhibited monkey and human acetylcholinesterases.

    Science.gov (United States)

    Luo, Chunyuan; Tong, Min; Maxwell, Donald M; Saxena, Ashima

    2008-09-25

    Non-human primates are valuable animal models that are used for the evaluation of nerve agent toxicity as well as antidotes and results from animal experiments are extrapolated to humans. It has been demonstrated that the efficacy of an oxime primarily depends on its ability to reactivate nerve agent-inhibited acetylcholinesterase (AChE). If the in vitro oxime reactivation of nerve agent-inhibited animal AChE is similar to that of human AChE, it is likely that the results of an in vivo animal study will reliably extrapolate to humans. Therefore, the goal of this study was to compare the aging and reactivation of human and different monkey (Rhesus, Cynomolgus, and African Green) AChEs inhibited by GF, GD, and VR. The oximes examined include the traditional oxime 2-PAM, two H-oximes HI-6 and HLo-7, and the new candidate oxime MMB4. Results indicate that oxime reactivation of all three monkey AChEs was very similar to human AChE. The maximum difference in the second-order reactivation rate constant between human and three monkey AChEs or between AChEs from different monkey species was 5-fold. Aging rate constants of GF-, GD-, and VR-inhibited monkey AChEs were very similar to human AChE except for GF-inhibited monkey AChEs, which aged 2-3 times faster than the human enzyme. The results of this study suggest that all three monkey species are suitable animal models for nerve agent antidote evaluation since monkey AChEs possess similar biochemical/pharmacological properties to human AChE.

  19. Aging and immortality: quasi-programmed senescence and its pharmacologic inhibition.

    Science.gov (United States)

    Blagosklonny, Mikhail V

    2006-09-01

    While ruling out programmed aging, evolutionary theory predicts a quasi-program for aging, a continuation of the developmental program that is not turned off, is constantly on, becoming hyper-functional and damaging, causing diseases of aging. Could it be switched off pharmacologically? This would require identification of a molecular target involved in cell senescence, organism aging and diseases of aging. Notably, cell senescence is associated with activation of the TOR (target of rapamycin) nutrient- and mitogen-sensing pathway, which promotes cell growth, even though cell cycle is blocked. Is TOR involved in organism aging? In fact, in yeast (where the cell is the organism), caloric restriction, rapamycin and mutations that inhibit TOR all slow down aging. In animals from worms to mammals caloric restrictions, life-extending agents, and numerous mutations that increase longevity all converge on the TOR pathway. And, in humans, cell hypertrophy, hyper-function and hyperplasia, typically associated with activation of TOR, contribute to diseases of aging. Theoretical and clinical considerations suggest that rapamycin may be effective against atherosclerosis, hypertension and hyper-coagulation (thus, preventing myocardial infarction and stroke), osteoporosis, cancer, autoimmune diseases and arthritis, obesity, diabetes, macula-degeneration, Alzheimer's and Parkinson's diseases. Finally, I discuss that extended life span will reveal new causes for aging (e.g., ROS, 'wear and tear', Hayflick limit, stem cell exhaustion) that play a limited role now, when quasi-programmed senescence kills us first.

  20. Increased fetal endocardial echogenicity mimicking endocardial fibroelastosis following maternal organophosphorus poisoning and its complete regression in utero

    International Nuclear Information System (INIS)

    Balakumar, Karippaliyil; Misha, Kannan; Milind, Karippaliyil

    2013-01-01

    Fetal endocardial fibroelastosis (EFE) has been diagnosed by antenatal ultrasonography in the past few years. A typical case of isolated endocardial fibroelastosis is illustrated here, in a fetus of 22 weeks of gestational age exposed to maternal organophosphorus poisoning at 20 weeks. No other structural cardiac or other systemic anomalies were detected in this fetus. The abnormal fetal echocardiographic features mimicking endocardial fibroelastosis completely regressed after 14 weeks and a normal full-term baby was delivered. Postnatal echocardiogram showed normal cardiac parameters. The diagnostic features mimicking EFE following maternal organophosphorus poisoning at 20 weeks of gestational age and the subsequent complete reversal of these changes after 14 weeks of diagnosis are reported for the first time in the literature

  1. Simple, specific analysis of organophosphorus and carbamate pesticides in sediments using column extraction and gas chromatography

    Science.gov (United States)

    Belisle, A.A.; Swineford, D.M.

    1988-01-01

    A simple, specific procedure was developed for the analysis of organophosphorus and carbamate pesticides in sediment. The wet soil was mixed with anhydrous sodium sulfate to bind water and the residues were column extracted in acetone:methylene chloride (1:l,v/v). Coextracted water was removed by additional sodium sulfate packed below the sample mixture. The eluate was concentrated and analyzed directly by capillary gas chromatography using phosphorus and nitrogen specific detectors. Recoveries averaged 93 % for sediments extracted shortly after spiking, but decreased significantly as the samples aged.

  2. Aging well: Processing speed inhibition and working memory related to balance and aerobic endurance.

    Science.gov (United States)

    Zettel-Watson, Laura; Suen, Meagan; Wehbe, Lara; Rutledge, Dana N; Cherry, Barbara J

    2017-01-01

    The present study explored whether certain physical performance measures could be linked to specific cognitive domains in healthy older adults. A total of 50 adults (mean age 69.5 years, SD 8.1) were evaluated on physical performance using measures of balance (Fullerton Advanced Balance Scale), functional mobility (8-ft up-and-go), lower body strength (30-s chair stand), gait (30-ft walk velocity) and aerobic endurance (6-min walk). Cognitive measures included Stroop Color-Word Test, Digit Span Backward, Trail Making Tests, Everyday Problems Test, Digit Symbol Substitution and a Brown-Peterson test. Principal component analyses reduced cognition to domains of processing speed, inhibition and working memory. Hierarchical regression analyses were carried out with age and each physical measure as potential predictors of the three cognitive domains. The balance scale and 6-min walk were specifically associated with processing speed, inhibition and working memory. Better dynamic balance and aerobic endurance predicted enhanced processing speed, inhibition and working memory in older adults, with these last two domains considered components of executive function. Geriatr Gerontol Int 2017; 17: 108-115. © 2015 Japan Geriatrics Society.

  3. Caspase inhibition in select olfactory neurons restores innate attraction behavior in aged Drosophila.

    Directory of Open Access Journals (Sweden)

    Takahiro Chihara

    2014-06-01

    Full Text Available Sensory and cognitive performance decline with age. Neural dysfunction caused by nerve death in senile dementia and neurodegenerative disease has been intensively studied; however, functional changes in neural circuits during the normal aging process are not well understood. Caspases are key regulators of cell death, a hallmark of age-related neurodegeneration. Using a genetic probe for caspase-3-like activity (DEVDase activity, we have mapped age-dependent neuronal changes in the adult brain throughout the lifespan of Drosophila. Spatio-temporally restricted caspase activation was observed in the antennal lobe and ellipsoid body, brain structures required for olfaction and visual place memory, respectively. We also found that caspase was activated in an age-dependent manner in specific subsets of Drosophila olfactory receptor neurons (ORNs, Or42b and Or92a neurons. These neurons are essential for mediating innate attraction to food-related odors. Furthermore, age-induced impairments of neural transmission and attraction behavior could be reversed by specific inhibition of caspase in these ORNs, indicating that caspase activation in Or42b and Or92a neurons is responsible for altering animal behavior during normal aging.

  4. Caspase inhibition in select olfactory neurons restores innate attraction behavior in aged Drosophila.

    Science.gov (United States)

    Chihara, Takahiro; Kitabayashi, Aki; Morimoto, Michie; Takeuchi, Ken-ichi; Masuyama, Kaoru; Tonoki, Ayako; Davis, Ronald L; Wang, Jing W; Miura, Masayuki

    2014-06-01

    Sensory and cognitive performance decline with age. Neural dysfunction caused by nerve death in senile dementia and neurodegenerative disease has been intensively studied; however, functional changes in neural circuits during the normal aging process are not well understood. Caspases are key regulators of cell death, a hallmark of age-related neurodegeneration. Using a genetic probe for caspase-3-like activity (DEVDase activity), we have mapped age-dependent neuronal changes in the adult brain throughout the lifespan of Drosophila. Spatio-temporally restricted caspase activation was observed in the antennal lobe and ellipsoid body, brain structures required for olfaction and visual place memory, respectively. We also found that caspase was activated in an age-dependent manner in specific subsets of Drosophila olfactory receptor neurons (ORNs), Or42b and Or92a neurons. These neurons are essential for mediating innate attraction to food-related odors. Furthermore, age-induced impairments of neural transmission and attraction behavior could be reversed by specific inhibition of caspase in these ORNs, indicating that caspase activation in Or42b and Or92a neurons is responsible for altering animal behavior during normal aging.

  5. Identification and isolation of bacteria containing OPH enzyme for biodegradation of organophosphorus pesticide diazinon from contaminated agricultural soil

    Directory of Open Access Journals (Sweden)

    Sara Mobarakpoor

    2015-04-01

    Full Text Available Background: Organophosphorus insecticide diazinon has been widely used in agriculture and has the ability to transfer and accumulate in soil, water and animal tissues, and to induce toxicity in plants, animals and humans. In humans, diazinon inhibits nerve transmission by inactivating acetylcholinesterase enzyme. The present study was carried out to identify bacteria containing OPH enzyme for biodegradation of diazinon from contaminated agricultural soil. Methods: In this study, 8 contaminated agricultural soil samples that were exposed to pesticides, especially diazinon in the last two decades, were collected from the farms of Hamedan province. After preparing the media, for isolation of several bacterial strains containing OPH enzyme that are capable of biodegrading organophosphorus pesticides by diazinon enzymatic hydrolysis, bacterial genomic DNA extraction, plasmid product sequencing, phylogenetic sequence processing and phylogenetic tree drawing were carried out. Results: Eight bacterial strains, capable of secreting OPH enzyme, were isolated from soil samples, one of which named BS-1 with 86% similarity to Bacillus safensis displayed the highest organophosphate-hydrolyzing capability and can be used as a source of carbon and phosphorus. Conclusion: It can be concluded that the isolated bacterial strain identified in this study with OPH enzyme secretion has the potential for biodegradation of organophosphorus pesticides, especially diazinon in invitro conditions. Also, further studies such as the environmental stability and interaction, production strategies, safety, cost-benefit, environmental destructive parameters, and, toxicological, genetic and biochemical aspects are recommended prior to the application of bacterial strains in the field-scale bioremediation.

  6. Osmoregulatory function in ducks following ingestion of the organophosphorus insecticide fenthion

    Science.gov (United States)

    Rattner, B.A.; Fleming, W.J.; Murray, H.C.

    1983-01-01

    Salt gland function and osmoregulation in aquatic birds drinking hyperosmotic water has been suggested to be impaired by organophosphorus insecticides. To test this hypothesis, adult black ducks (Anas rubripes) were provided various regimens of fresh or salt (1.5% NaCl) water before, during, and after ingestion of mash containing 21 ppm fenthion. Ducks were bled by jugular venipuncture after I, 7. and 12 days of treatment, and were then killed. Brain and salt gland acetylcholinesterase activities were substantially inhibited (44-61% and 14-36%) by fenthion. However, salt gland weight and Na + -K + -ATPase activity, and plasma Na + , CI- , and osmolality, were uniformly elevated in all groups receiving salt water including those ingesting fenthion. In a second study, salt gland Na + -K + -ATPase activity in mallards (A. platyrhynchos) was not affected after in vitro incubation with either fenthion or fenthion oxon at concentrations ranging from 0.04 to 400 ?M, but was reduced in the presence of 40 and 400 ?M DDE (positive control). These findings suggest that environmentally realistic concentrations of organophosphorus insecticides do not markedly affect osmoregulatory function in adult black ducks.

  7. Inhibition of GLO1 in Glioblastoma Multiforme Increases DNA-AGEs, Stimulates RAGE Expression, and Inhibits Brain Tumor Growth in Orthotopic Mouse Models

    Directory of Open Access Journals (Sweden)

    Rahul Jandial

    2018-01-01

    Full Text Available Cancers that exhibit the Warburg effect may elevate expression of glyoxylase 1 (GLO1 to detoxify the toxic glycolytic byproduct methylglyoxal (MG and inhibit the formation of pro-apoptotic advanced glycation endproducts (AGEs. Inhibition of GLO1 in cancers that up-regulate glycolysis has been proposed as a therapeutic targeting strategy, but this approach has not been evaluated for glioblastoma multiforme (GBM, the most aggressive and difficult to treat malignancy of the brain. Elevated GLO1 expression in GBM was established in patient tumors and cell lines using bioinformatics tools and biochemical approaches. GLO1 inhibition in GBM cell lines and in an orthotopic xenograft GBM mouse model was examined using both small molecule and short hairpin RNA (shRNA approaches. Inhibition of GLO1 with S-(p-bromobenzyl glutathione dicyclopentyl ester (p-BrBzGSH(Cp2 increased levels of the DNA-AGE N2-1-(carboxyethyl-2′-deoxyguanosine (CEdG, a surrogate biomarker for nuclear MG exposure; substantially elevated expression of the immunoglobulin-like receptor for AGEs (RAGE; and induced apoptosis in GBM cell lines. Targeting GLO1 with shRNA similarly increased CEdG levels and RAGE expression, and was cytotoxic to glioma cells. Mice bearing orthotopic GBM xenografts treated systemically with p-BrBzGSH(Cp2 exhibited tumor regression without significant off-target effects suggesting that GLO1 inhibition may have value in the therapeutic management of these drug-resistant tumors.

  8. Inhibition of GLO1 in Glioblastoma Multiforme Increases DNA-AGEs, Stimulates RAGE Expression, and Inhibits Brain Tumor Growth in Orthotopic Mouse Models.

    Science.gov (United States)

    Jandial, Rahul; Neman, Josh; Lim, Punnajit P; Tamae, Daniel; Kowolik, Claudia M; Wuenschell, Gerald E; Shuck, Sarah C; Ciminera, Alexandra K; De Jesus, Luis R; Ouyang, Ching; Chen, Mike Y; Termini, John

    2018-01-30

    Cancers that exhibit the Warburg effect may elevate expression of glyoxylase 1 (GLO1) to detoxify the toxic glycolytic byproduct methylglyoxal (MG) and inhibit the formation of pro-apoptotic advanced glycation endproducts (AGEs). Inhibition of GLO1 in cancers that up-regulate glycolysis has been proposed as a therapeutic targeting strategy, but this approach has not been evaluated for glioblastoma multiforme (GBM), the most aggressive and difficult to treat malignancy of the brain. Elevated GLO1 expression in GBM was established in patient tumors and cell lines using bioinformatics tools and biochemical approaches. GLO1 inhibition in GBM cell lines and in an orthotopic xenograft GBM mouse model was examined using both small molecule and short hairpin RNA (shRNA) approaches. Inhibition of GLO1 with S -( p -bromobenzyl) glutathione dicyclopentyl ester ( p- BrBzGSH(Cp)₂) increased levels of the DNA-AGE N ²-1-(carboxyethyl)-2'-deoxyguanosine (CEdG), a surrogate biomarker for nuclear MG exposure; substantially elevated expression of the immunoglobulin-like receptor for AGEs (RAGE); and induced apoptosis in GBM cell lines. Targeting GLO1 with shRNA similarly increased CEdG levels and RAGE expression, and was cytotoxic to glioma cells. Mice bearing orthotopic GBM xenografts treated systemically with p -BrBzGSH(Cp)₂ exhibited tumor regression without significant off-target effects suggesting that GLO1 inhibition may have value in the therapeutic management of these drug-resistant tumors.

  9. The aging motor system as a model for plastic changes of GABA-mediated intracortical inhibition and their behavioral relevance.

    Science.gov (United States)

    Heise, Kirstin-F; Zimerman, Maximo; Hoppe, Julia; Gerloff, Christian; Wegscheider, Karl; Hummel, Friedhelm C

    2013-05-22

    Since GABAA-mediated intracortical inhibition has been shown to underlie plastic changes throughout the lifespan from development to aging, here, the aging motor system was used as a model to analyze the interdependence of plastic alterations within the inhibitory motorcortical network and level of behavioral performance. Double-pulse transcranial magnetic stimulation (dpTMS) was used to examine inhibition by means of short-interval intracortical inhibition (SICI) of the contralateral primary motor cortex in a sample of 64 healthy right-handed human subjects covering a wide range of the adult lifespan (age range 20-88 years, mean 47.6 ± 20.7, 34 female). SICI was evaluated during resting state and in an event-related condition during movement preparation in a visually triggered simple reaction time task. In a subgroup (N = 23), manual motor performance was tested with tasks of graded dexterous demand. Weak resting-state inhibition was associated with an overall lower manual motor performance. Better event-related modulation of inhibition correlated with better performance in more demanding tasks, in which fast alternating activation of cortical representations are necessary. Declining resting-state inhibition was associated with weakened event-related modulation of inhibition. Therefore, reduced resting-state inhibition might lead to a subsequent loss of modulatory capacity, possibly reflecting malfunctioning precision in GABAAergic neurotransmission; the consequence is an inevitable decline in motor function.

  10. Pralidoxime in acute organophosphorus insecticide poisoning--a randomised controlled trial.

    Directory of Open Access Journals (Sweden)

    Michael Eddleston

    2009-06-01

    Full Text Available Poisoning with organophosphorus (OP insecticides is a major global public health problem, causing an estimated 200,000 deaths each year. Although the World Health Organization recommends use of pralidoxime, this antidote's effectiveness remains unclear. We aimed to determine whether the addition of pralidoxime chloride to atropine and supportive care offers benefit.We performed a double-blind randomised placebo-controlled trial of pralidoxime chloride (2 g loading dose over 20 min, followed by a constant infusion of 0.5 g/h for up to 7 d versus saline in patients with organophosphorus insecticide self-poisoning. Mortality was the primary outcome; secondary outcomes included intubation, duration of intubation, and time to death. We measured baseline markers of exposure and pharmacodynamic markers of response to aid interpretation of clinical outcomes. Two hundred thirty-five patients were randomised to receive pralidoxime (121 or saline placebo (114. Pralidoxime produced substantial and moderate red cell acetylcholinesterase reactivation in patients poisoned by diethyl and dimethyl compounds, respectively. Mortality was nonsignificantly higher in patients receiving pralidoxime: 30/121 (24.8% receiving pralidoxime died, compared with 18/114 (15.8% receiving placebo (adjusted hazard ratio [HR] 1.69, 95% confidence interval [CI] 0.88-3.26, p = 0.12. Incorporating the baseline amount of acetylcholinesterase already aged and plasma OP concentration into the analysis increased the HR for patients receiving pralidoxime compared to placebo, further decreasing the likelihood that pralidoxime is beneficial. The need for intubation was similar in both groups (pralidoxime 26/121 [21.5%], placebo 24/114 [21.1%], adjusted HR 1.27 [95% CI 0.71-2.29]. To reduce confounding due to ingestion of different insecticides, we further analysed patients with confirmed chlorpyrifos or dimethoate poisoning alone, finding no evidence of benefit.Despite clear reactivation of

  11. Biodegradation of organophosphorus pesticides by soil bacteria

    Science.gov (United States)

    de Pasquale, C.; Fodale, R.; Lo Piccolo, L.; Palazzolo, E.; Alonzo, G.; Quatrini, P.

    2009-04-01

    A number of studies in the 1980s and 1990s showed that crop-protection products, applied to drained fields, could move downwards through the soil profile and to the groundwater. Organophosphorus insecticides (OPs) are used all over the world for crop protection, for other agricultural practices such as sheep dipping and, in aquaculture, for the control of sea lice. Ops besides showing a specific neurotoxicity and have also been related to various modern diseases, including Creutzfeldt-Jakob (CJD) and the Gulf War syndrome. Although OPs are less persistent than Organoclorine pesticides (OCs), they still constitute an environmental risks thus increasing the social concern about their levels in soils, surface waters, and ground waters. Degradation of OPs by microorganisms has been assessed for a few bacterial strains. In the present study the OPs degrading potential of indigenous soil microorganisms was investigated. Using enrichment cultures in which parathion was the only C and energy sources many bacterial strains were isolated from OPs contaminated and pristine agricultural soils characterized by different physico-chemical properties. More than 40 potential OPs degraders were isolated and grouped in operational taxonomic units (OTU) using analysis of polymorphism showed by the ribosomal internal transcribed spacer (ITS). Partial sequencing of 16S rRNA gene of representative isolates of each OTU revealed that most of them belong to Proteobacteria and Actinobacteria. All the analyzed soils showed the presence of putative OPs degraders: the highest diversity was found in organic cultivated soils, the lowest in chemically cultivated soils. Degradation of different OPs, characterized by different physical and chemical properties, was obtained by different selected representative strains using SPME GC-MS analysis on water and soil microcosms. The results showed that, after the incubation period, the amount of pesticide residues were in the range 20-80%. Some of the

  12. Acute organophosphorus compound poisoning in cattle: A case report

    African Journals Online (AJOL)

    A case of an acute organophosphorus compound, GOLDFLEECE poisoning involving 39 cattle at Abubakar Tafawa Balewa University, Bauchi is reported. The animals were overexposed to the compound following routine tick spray. Within 15 minutes after the spray of the compound, 26 animals were recumbent showing ...

  13. Acute organo-phosphorus pesticide poisoning in North Karnataka ...

    African Journals Online (AJOL)

    Background: Pesticide poisoning is an important cause of morbidity and mortality in India. Objectives: To assess the oxidative damage, hemoglobin level and leukocyte count in acute organophosphorus pesticide poisoning. Methods: Plasma cholinesterase was assessed as a toxicity marker. Oxidative damage was ...

  14. Optimization of Cholinesterase-Based Catalytic Bioscavengers Against Organophosphorus Agents.

    Science.gov (United States)

    Lushchekina, Sofya V; Schopfer, Lawrence M; Grigorenko, Bella L; Nemukhin, Alexander V; Varfolomeev, Sergei D; Lockridge, Oksana; Masson, Patrick

    2018-01-01

    Organophosphorus agents (OPs) are irreversible inhibitors of acetylcholinesterase (AChE). OP poisoning causes major cholinergic syndrome. Current medical counter-measures mitigate the acute effects but have limited action against OP-induced brain damage. Bioscavengers are appealing alternative therapeutic approach because they neutralize OPs in bloodstream before they reach physiological targets. First generation bioscavengers are stoichiometric bioscavengers. However, stoichiometric neutralization requires administration of huge doses of enzyme. Second generation bioscavengers are catalytic bioscavengers capable of detoxifying OPs with a turnover. High bimolecular rate constants ( k cat / K m > 10 6 M -1 min -1 ) are required, so that low enzyme doses can be administered. Cholinesterases (ChE) are attractive candidates because OPs are hemi-substrates. Moderate OP hydrolase (OPase) activity has been observed for certain natural ChEs and for G117H-based human BChE mutants made by site-directed mutagenesis. However, before mutated ChEs can become operational catalytic bioscavengers their dephosphylation rate constant must be increased by several orders of magnitude. New strategies for converting ChEs into fast OPase are based either on combinational approaches or on computer redesign of enzyme. The keystone for rational conversion of ChEs into OPases is to understand the reaction mechanisms with OPs. In the present work we propose that efficient OP hydrolysis can be achieved by re-designing the configuration of enzyme active center residues and by creating specific routes for attack of water molecules and proton transfer. Four directions for nucleophilic attack of water on phosphorus atom were defined. Changes must lead to a novel enzyme, wherein OP hydrolysis wins over competing aging reactions. Kinetic, crystallographic, and computational data have been accumulated that describe mechanisms of reactions involving ChEs. From these studies, it appears that introducing

  15. Optimization of Cholinesterase-Based Catalytic Bioscavengers Against Organophosphorus Agents

    Directory of Open Access Journals (Sweden)

    Sofya V. Lushchekina

    2018-03-01

    Full Text Available Organophosphorus agents (OPs are irreversible inhibitors of acetylcholinesterase (AChE. OP poisoning causes major cholinergic syndrome. Current medical counter-measures mitigate the acute effects but have limited action against OP-induced brain damage. Bioscavengers are appealing alternative therapeutic approach because they neutralize OPs in bloodstream before they reach physiological targets. First generation bioscavengers are stoichiometric bioscavengers. However, stoichiometric neutralization requires administration of huge doses of enzyme. Second generation bioscavengers are catalytic bioscavengers capable of detoxifying OPs with a turnover. High bimolecular rate constants (kcat/Km > 106 M−1min−1 are required, so that low enzyme doses can be administered. Cholinesterases (ChE are attractive candidates because OPs are hemi-substrates. Moderate OP hydrolase (OPase activity has been observed for certain natural ChEs and for G117H-based human BChE mutants made by site-directed mutagenesis. However, before mutated ChEs can become operational catalytic bioscavengers their dephosphylation rate constant must be increased by several orders of magnitude. New strategies for converting ChEs into fast OPase are based either on combinational approaches or on computer redesign of enzyme. The keystone for rational conversion of ChEs into OPases is to understand the reaction mechanisms with OPs. In the present work we propose that efficient OP hydrolysis can be achieved by re-designing the configuration of enzyme active center residues and by creating specific routes for attack of water molecules and proton transfer. Four directions for nucleophilic attack of water on phosphorus atom were defined. Changes must lead to a novel enzyme, wherein OP hydrolysis wins over competing aging reactions. Kinetic, crystallographic, and computational data have been accumulated that describe mechanisms of reactions involving ChEs. From these studies, it appears that

  16. Resveratrol ameliorates aging-related metabolic phenotypes by inhibiting cAMP phosphodiesterases.

    Science.gov (United States)

    Park, Sung-Jun; Ahmad, Faiyaz; Philp, Andrew; Baar, Keith; Williams, Tishan; Luo, Haibin; Ke, Hengming; Rehmann, Holger; Taussig, Ronald; Brown, Alexandra L; Kim, Myung K; Beaven, Michael A; Burgin, Alex B; Manganiello, Vincent; Chung, Jay H

    2012-02-03

    Resveratrol, a polyphenol in red wine, has been reported as a calorie restriction mimetic with potential antiaging and antidiabetogenic properties. It is widely consumed as a nutritional supplement, but its mechanism of action remains a mystery. Here, we report that the metabolic effects of resveratrol result from competitive inhibition of cAMP-degrading phosphodiesterases, leading to elevated cAMP levels. The resulting activation of Epac1, a cAMP effector protein, increases intracellular Ca(2+) levels and activates the CamKKβ-AMPK pathway via phospholipase C and the ryanodine receptor Ca(2+)-release channel. As a consequence, resveratrol increases NAD(+) and the activity of Sirt1. Inhibiting PDE4 with rolipram reproduces all of the metabolic benefits of resveratrol, including prevention of diet-induced obesity and an increase in mitochondrial function, physical stamina, and glucose tolerance in mice. Therefore, administration of PDE4 inhibitors may also protect against and ameliorate the symptoms of metabolic diseases associated with aging. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. Assessment of some biochemical and hematological parameters in treated with the organophosphorus insecticide cyanox

    International Nuclear Information System (INIS)

    ElMahdy, A.A.; Fayz, V.; Hassanin, M.M.

    2002-01-01

    The effect of single acute oral doses of 29 and 58 mg/kg of cyanox (an organophosphorus pesticide) on selected biochemical and hematological parameters in male rats were investigated. This compound inhibited blood acetylcholine esterase (AChE) significantly, over 72 hours post-treatment with the higher dose level. Serum alkaline phosphatase (ALP) was significantly depressed, 48 hr after treatment with 58 mg/kg. Serum bilirubin was elevated significantly after 48 and 24 hr of treatment with 29 and 58 mg/kg, respectively. Serum cholesterol increased significantly over 48 hr post-treatment with both dose levels.Hypertriglyceridemia was noticed only in the higher dose group. Serum total lipids were increased significantly at both dose levels. A slight treatment-related effect was observed in serum creatinine level. The hematological investigations revealed the occurrence of macrocytic normochromic anemia that was more evident in the lower dose group

  18. Metformin inhibits age-related centrosome amplification in Drosophila midgut stem cells through AKT/TOR pathway.

    Science.gov (United States)

    Na, Hyun-Jin; Park, Joung-Sun; Pyo, Jung-Hoon; Jeon, Ho-Jun; Kim, Young-Shin; Arking, Robert; Yoo, Mi-Ae

    2015-07-01

    We delineated the mechanism regulating the inhibition of centrosome amplification by metformin in Drosophila intestinal stem cells (ISCs). Age-related changes in tissue-resident stem cells may be closely associated with tissue aging and age-related diseases, such as cancer. Centrosome amplification is a hallmark of cancers. Our recent work showed that Drosophila ISCs are an excellent model for stem cell studies evaluating age-related increase in centrosome amplification. Here, we showed that metformin, a recognized anti-cancer drug, inhibits age- and oxidative stress-induced centrosome amplification in ISCs. Furthermore, we revealed that this effect is mediated via down-regulation of AKT/target of rapamycin (TOR) activity, suggesting that metformin prevents centrosome amplification by inhibiting the TOR signaling pathway. Additionally, AKT/TOR signaling hyperactivation and metformin treatment indicated a strong correlation between DNA damage accumulation and centrosome amplification in ISCs, suggesting that DNA damage might mediate centrosome amplification. Our study reveals the beneficial and protective effects of metformin on centrosome amplification via AKT/TOR signaling modulation. We identified a new target for the inhibition of age- and oxidative stress-induced centrosome amplification. We propose that the Drosophila ISCs may be an excellent model system for in vivo studies evaluating the effects of anti-cancer drugs on tissue-resident stem cell aging. Copyright © 2015 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  19. The roles of sensory function and cognitive load in age differences in inhibition: Evidence from the Stroop task.

    Science.gov (United States)

    Peng, Huamao; Gao, Yue; Mao, Xiaofei

    2017-02-01

    To explore the roles of visual function and cognitive load in aging of inhibition, the present study adopted a 2 (visual perceptual stress: noise, nonnoise) × 2 (cognitive load: low, high) × 2 (age: young, old) mixed design. The Stroop task was adopted to measure inhibition. The task presentation was masked with Gaussian noise according to the visual function of each individual in order to match visual perceptual stress between age groups. The results indicated that age differences in the Stroop effect were influenced by visual function and cognitive load. When the cognitive load was low, older adults exhibited a larger Stroop effect than did younger adults in the nonnoise condition, and this age difference disappeared when the visual noise of the 2 age groups was matched. Conversely, in the high cognitive load condition, we observed significant age differences in the Stroop effect in both the nonnoise and noise conditions. The additional cognitive load made the age differences in the Stroop task reappear even when visual perceptual stress was equivalent. These results demonstrate that visual function plays an important role in the aging of inhibition and its role is moderated by cognitive load. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  20. [How aliphatic alcohols and ph affect reactional capability of the horse blood serum cholinesterase at its interaction with organophosphorus inhibitors].

    Science.gov (United States)

    Basova, N E; Kormilitsin, B N; Perchenok, A Iu; Rozengart, E V; Saakov, V S; Suvorov, A A

    2013-01-01

    There was studied action of aliphatic alcohols (ethanol, propanol, isopropanol, n-butanol, isobutanol, secbutanol, tretbetanol) and pH on various kinds of reactional capability the serum cholinesterase. At the alcohols-affected inhibition of the cholinesterase hydrolytic activity, the determining role was played not the total number carbon atoms in the alcohol molecule, but by the "effective length" of the carbohydrate chain. The fact that the presence of alcohols did not affect parameters of the reverse cholinesterase inhibition with onium ions tetramethylammonium and choline allows suggesting the absence of effect solvents on specific acetylcholine sorption in the enzyme active center. With aid of two rows of hydrophobic organophosphorus inhibitors (OPI), we have managed to estimate both the degree and the character itself of the modifying action of alcohols and pH on the process of irreversible inhibition of serum cholinesterase.

  1. Specificity of carboxylesterase protection against the toxicity of organophosphorus compounds. (Reannouncement with new availability information)

    Energy Technology Data Exchange (ETDEWEB)

    Maxwell, D.M.

    1992-12-31

    The ability of endogenous carboxylesterase (CaE) to protect against the lethal effects of a variety of organophosphorus (OP) compounds was examined in rats. The in vivo protection provided by endogenous CaE was measured by the difference in the LD50 values of OP compounds in controlrats and rats whose CaE activity had been inhibited by sc injection with2 mg/kg of 2-(O cresyl)-4H-1,3,2-benzodi oxaphosphorin-2-oxide. Endogenous CaE provided significant protection against the in vivo toxicity of soman, sarin, tabun, and paraoxon, but not against dichlorvos, diisopropyl fluorophosphate, or ethoxymethyl-S-2- (DIISOPROPYLAMINO)ETHYL THIOPHOSPHONATE (VX). The relationship between the in vivo CaE protection against OP compounds and their relative reactivities with CaE and acetylcholinesterase (AChE) was evaluated by measuring the in vitro bimolecular rate constants (ki) for inhibition of plasma CaE and brain AChE. Except for VX, ki values for CaE inhibition varied <10-fold while ki values for AChE inhibition varied 105-fold. Chemical warfare agents, Nerve agents, Organophosphoruscompound soman, VX, Carboxylesterase, Protection, Pretreatment.

  2. Denaturation/Renaturation of Organophosphorus Acid Anhydrolase (OPAA) Using Guanidinium Hydrochloride and Urea

    National Research Council Canada - National Science Library

    Ong, K. K; Sun, Z; Cheng, T. C; Wei, Y; Yuan, J. M; Yin, R

    2004-01-01

    .... Using organophosphorus acid anhydrolase (OPAA) as the model protein, a guanidinium hydrochloride and urea denaturation/renaturation study was conducted and measured both optically and enzymatically...

  3. Organophosphorus pentavalent compounds: history, synthetic methods of preparation and application as insecticides and antitumor agents

    International Nuclear Information System (INIS)

    Santos, Viviane Martins Rebello dos; Donnici, Claudio Luis; DaCosta, Joao Batista Neves; Caixeiro, Janaina Marques Rodrigues

    2007-01-01

    This paper is a review of the history, synthesis and application of organophosphorus compounds, especially of those of pentavalent phosphorus, such as phosphoramidates, phosphorothioates, phosphonates and phosphonic acids with insecticide and anticancer activities. The organophosphorus compounds with agrochemical applications show great structural variety, They include not only insecticides, but also fungicides, herbicides, and others. The large variety of commercially available organophosphorus pesticides is remarkable. Even more interesting is the high efficiency of some organophosphorus compounds as anticancer agents such as cyclophosphamide and its derivatives. (author)

  4. Biodegradation and Utilization of Organophosphorus Pesticide Malathion by Cyanobacteria

    Directory of Open Access Journals (Sweden)

    Wael M. Ibrahim

    2014-01-01

    Full Text Available Three strains of filamentous Cyanobacteria were used to study their growth and utilization of organophosphorus pesticide malathion. A sharp decrease in the growth of the algal strains was observed by increasing the concentration of malathion. Amongst them Nostoc muscorum tolerated different concentrations and was recorded as the highest efficient strain for biodegradation (91% of this compound. Moreover, carbohydrate and protein content of their cells overtopped the other strains especially at higher concentrations. The algal strains were further subjected to grow under P-limitation in absence and presence of malathion. Although, the algal growth under P-limitation recorded a very poor level, a massive enhanced growth and phosphorous content of cells were obtained when the P-limited medium was amended with malathion. This study clarified that N. muscorum with its capability to utilize malathion as a sole phosphorous source is considered as an inexpensive and efficient biotechnology for remediation of organophosphorus pesticide from contaminated wastewater.

  5. Acute organophosphorus poisoning complicated by acute coronary syndrome.

    Science.gov (United States)

    Pankaj, Madhu; Krishna, Kavita

    2014-07-01

    We report a case of 30 year old alcoholic male admitted with vomiting, drowsiness, limb weakness and fasciculations after alleged history of consumption of 30 ml of chlorpyriphos insecticide. He had low serum cholinesterase levels. With standard treatment for organophosphorus poisoning (OPP), he improved gradually until day 5, when he developed neck and limb weakness and respiratory distress. This intermediate syndrome was treated with oximes, atropine and artificial ventilation. During treatment, his ECG showed fresh changes of ST elevation. High CPK & CPK-MB levels, septal hypokinesia on 2D echo suggested acute coronary syndrome. Coronary angiography was postponed due to his bedridden and obtunded status. The patient finally recovered fully by day 15 and was discharged. Acute coronary syndrome is a rare occurrence in OP poisoning. The present case thus emphasises the need for careful electrocardiographic and enzymatic monitoring of all patients of organophosphorus poisoning to prevent potential cardiac complication which can prove fatal.

  6. Hypothalamic gene transfer of BDNF inhibits breast cancer progression and metastasis in middle age obese mice.

    Science.gov (United States)

    Liu, Xianglan; McMurphy, Travis; Xiao, Run; Slater, Andrew; Huang, Wei; Cao, Lei

    2014-07-01

    Activation of the hypothalamus-adipocyte axis is associated with an antiobesity and anticancer phenotype in animal models of melanoma and colon cancer. Brain-derived neurotrophic factor (BDNF) is a key mediator in the hypothalamus leading to preferential sympathoneural activation of adipose tissue and the ensuing resistance to obesity and cancer. Here, we generated middle age obese mice by high fat diet feeding for a year and investigated the effects of hypothalamic gene transfer of BDNF on a hormone receptor-positive mammary tumor model. The recombinant adeno-associated viral vector-mediated overexpression of BDNF led to marked weight loss and decrease of adiposity without change of food intake. BDNF gene therapy improved glucose tolerance, alleviated steatosis, reduced leptin level, inhibited mouse breast cancer EO771 growth, and prevented the metastasis. The reduced tumor growth in BDNF-treated mice was associated with reduced angiogenesis, decreased proliferation, increased apoptosis, and reduced adipocyte recruitment and lipid accumulation. Moreover, BDNF gene therapy reduced inflammation markers in the hypothalamus, the mammary gland, the subcutaneous fat, and the mammary tumor. Our results suggest that manipulating a single gene in the brain may influence multiple mechanisms implicated in obesity-cancer association and provide a target for the prevention and treatment of both obesity and cancer.

  7. JNK inhibition reduces apoptosis and neovascularization in a murine model of age-related macular degeneration.

    Science.gov (United States)

    Du, Hongjun; Sun, Xufang; Guma, Monica; Luo, Jing; Ouyang, Hong; Zhang, Xiaohui; Zeng, Jing; Quach, John; Nguyen, Duy H; Shaw, Peter X; Karin, Michael; Zhang, Kang

    2013-02-05

    Age-related macular degeneration (AMD) is the leading cause of registered blindness among the elderly and affects over 30 million people worldwide. It is well established that oxidative stress, inflammation, and apoptosis play critical roles in pathogenesis of AMD. In advanced wet AMD, although, most of the severe vision loss is due to bleeding and exudation of choroidal neovascularization (CNV), and it is well known that vascular endothelial growth factor (VEGF) plays a pivotal role in the growth of the abnormal blood vessels. VEGF suppression therapy improves visual acuity in AMD patients. However, there are unresolved issues, including safety and cost. Here we show that mice lacking c-Jun N-terminal kinase 1 (JNK1) exhibit decreased inflammation, reduced CNV, lower levels of choroidal VEGF, and impaired choroidal macrophage recruitment in a murine model of wet AMD (laser-induced CNV). Interestingly, we also detected a substantial reduction in choroidal apoptosis of JNK1-deficient mice. Intravitreal injection of a pan-caspase inhibitor reduced neovascularization in the laser-induced CNV model, suggesting that apoptosis plays a role in laser-induced pathological angiogenesis. Intravitreal injection of a specific JNK inhibitor decreased choroidal VEGF expression and reduced pathological CNV. These results suggest that JNK1 plays a key role in linking oxidative stress, inflammation, macrophage recruitment apoptosis, and VEGF production in wet AMD and pharmacological JNK inhibition offers a unique and alternative avenue for prevention and treatment of AMD.

  8. Standardized Kaempferia parviflora Extract Inhibits Intrinsic Aging Process in Human Dermal Fibroblasts and Hairless Mice by Inhibiting Cellular Senescence and Mitochondrial Dysfunction

    Directory of Open Access Journals (Sweden)

    Ji-Eun Park

    2017-01-01

    Full Text Available Intrinsic skin aging is a complex biological phenomenon mainly caused by cellular senescence and mitochondrial dysfunction. This study evaluated the inhibitory effect of Kaempferia parviflora Wall ex. Baker ethanol extract (KPE on H2O2-stimulated cellular senescence and mitochondrial dysfunction both in vitro and in vivo. KPE significantly increased cell growth and suppressed senescence-associated β-galactosidase activation. KPE inhibited the expression of cell-cycle inhibitors (p53, p21, p16, and pRb and stimulated the expression of cell-cycle activators (E2F1 and E2F2. H2O2-induced hyperactivation of the phosphatidylinositol 3-kinase/protein kinase B (AKT signaling pathway was suppressed by KPE through regulated expression of forkhead box O3a (FoxO3a and mammalian target of rapamycin (mTOR. KPE attenuated inflammatory mediators (interleukin-6 (IL-6, IL-8, nuclear factor kappa B (NF-κB, and cyclooxygenase-2 (COX-2 and increased the mRNA expression of PGC-1α, ERRα, NRF1, and Tfam, which modulate mitochondrial biogenesis and function. Consequently, reduced ATP levels and increased ROS level were also reversed by KPE treatment. In hairless mice, KPE inhibited wrinkle formation, skin atrophy, and loss of elasticity by increasing the collagen and elastic fibers. The results indicate that KPE prevents intrinsic aging process in hairless mice by inhibiting cellular senescence and mitochondrial dysfunction, suggesting its potential as a natural antiaging agent.

  9. Novel organophosphorus compounds; synthesis, spectroscopy and X-ray crystallography

    Czech Academy of Sciences Publication Activity Database

    Shariatinia, Z.; Sohrabi, M.; Yousefi, M.; Kovaľ, Tomáš; Dušek, Michal

    2012-01-01

    Roč. 11, č. 2 (2012), s. 125-133 ISSN 1024-1221 Grant - others:AV ČR(CZ) AP0701 Program:Akademická prémie - Praemium Academiae Institutional research plan: CEZ:AV0Z10100521 Keywords : organophosphorus compounds * NMR * X-ray crystallography * hydrogen bond Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.686, year: 2012

  10. The application of green chemistry methods in organophosphorus synthesis

    International Nuclear Information System (INIS)

    Odinets, Irina L; Matveeva, E V

    2012-01-01

    Data concerning the synthesis of organophosphorus compounds in ionic liquids, in water and under solvent-free conditions are considered and summarized. It is shown that this strategy, which complies with the definition of green chemistry, has advantages in terms of the rate of the process and the yields of target products as compared with syntheses in common organic solvents. The Wittig, Horner–Wadsworth–Emmons, Kabachnik–Fields, Arbuzov and Michaelis reactions are considered as examples. The bibliography includes 178 references.

  11. Rapid biodegradation of organophosphorus pesticides by Stenotrophomonas sp. G1

    International Nuclear Information System (INIS)

    Deng, Shuyan; Chen, Yao; Wang, Daosheng; Shi, Taozhong; Wu, Xiangwei; Ma, Xin; Li, Xiangqiong; Hua, Rimao; Tang, Xinyun; Li, Qing X.

    2015-01-01

    Highlights: • Stenotrophomonas sp. G1 was isolated from chlorpyrifos contaminated sludge. • Strain G1 is closest to Stenotrophomonas acidaminiphila. • Strain G1 can efficiently degrade 8 organophosphorus pesticides (OPs). • Intracellular methyl parathion hydrolase is responsible for the OP degradation. • Three factors were orthogonally optimized for degradation of methyl parathion. - Abstract: Organophosphorus insecticides have been widely used, which are highly poisonous and cause serious concerns over food safety and environmental pollution. A bacterial strain being capable of degrading O,O-dialkyl phosphorothioate and O,O-dialkyl phosphate insecticides, designated as G1, was isolated from sludge collected at the drain outlet of a chlorpyrifos manufacture plant. Physiological and biochemical characteristics and 16S rDNA gene sequence analysis suggested that strain G1 belongs to the genus Stenotrophomonas. At an initial concentration of 50 mg/L, strain G1 degraded 100% of methyl parathion, methyl paraoxon, diazinon, and phoxim, 95% of parathion, 63% of chlorpyrifos, 38% of profenofos, and 34% of triazophos in 24 h. Orthogonal experiments showed that the optimum conditions were an inoculum volume of 20% (v/v), a substrate concentration of 50 mg/L, and an incubation temperature in 40 °C. p-Nitrophenol was detected as the metabolite of methyl parathion, for which intracellular methyl parathion hydrolase was responsible. Strain G1 can efficiently degrade eight organophosphorus pesticides (OPs) and is a very excellent candidate for applications in OP pollution remediation

  12. Rapid biodegradation of organophosphorus pesticides by Stenotrophomonas sp. G1

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Shuyan; Chen, Yao [Key Laboratory of Agri-food Safety of Anhui Province, Lab of Quality & Safety and Risk Assessment for Agro-products on Storage and Preservation (Hefei), Ministry of Agriculture, School of Resource and Environment, Anhui Agricultural University, Hefei 230036 (China); Wang, Daosheng [School of Life Science, Anhui Agricultural University, Hefei 230036 (China); Shi, Taozhong; Wu, Xiangwei; Ma, Xin; Li, Xiangqiong [Key Laboratory of Agri-food Safety of Anhui Province, Lab of Quality & Safety and Risk Assessment for Agro-products on Storage and Preservation (Hefei), Ministry of Agriculture, School of Resource and Environment, Anhui Agricultural University, Hefei 230036 (China); Hua, Rimao, E-mail: rimaohua@ahau.edu.cn [Key Laboratory of Agri-food Safety of Anhui Province, Lab of Quality & Safety and Risk Assessment for Agro-products on Storage and Preservation (Hefei), Ministry of Agriculture, School of Resource and Environment, Anhui Agricultural University, Hefei 230036 (China); Tang, Xinyun [School of Life Science, Anhui Agricultural University, Hefei 230036 (China); Li, Qing X. [Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, 1955 East–West Road, Honolulu, HI 957822 (United States)

    2015-10-30

    Highlights: • Stenotrophomonas sp. G1 was isolated from chlorpyrifos contaminated sludge. • Strain G1 is closest to Stenotrophomonas acidaminiphila. • Strain G1 can efficiently degrade 8 organophosphorus pesticides (OPs). • Intracellular methyl parathion hydrolase is responsible for the OP degradation. • Three factors were orthogonally optimized for degradation of methyl parathion. - Abstract: Organophosphorus insecticides have been widely used, which are highly poisonous and cause serious concerns over food safety and environmental pollution. A bacterial strain being capable of degrading O,O-dialkyl phosphorothioate and O,O-dialkyl phosphate insecticides, designated as G1, was isolated from sludge collected at the drain outlet of a chlorpyrifos manufacture plant. Physiological and biochemical characteristics and 16S rDNA gene sequence analysis suggested that strain G1 belongs to the genus Stenotrophomonas. At an initial concentration of 50 mg/L, strain G1 degraded 100% of methyl parathion, methyl paraoxon, diazinon, and phoxim, 95% of parathion, 63% of chlorpyrifos, 38% of profenofos, and 34% of triazophos in 24 h. Orthogonal experiments showed that the optimum conditions were an inoculum volume of 20% (v/v), a substrate concentration of 50 mg/L, and an incubation temperature in 40 °C. p-Nitrophenol was detected as the metabolite of methyl parathion, for which intracellular methyl parathion hydrolase was responsible. Strain G1 can efficiently degrade eight organophosphorus pesticides (OPs) and is a very excellent candidate for applications in OP pollution remediation.

  13. The Extract of Aster Koraiensis Prevents Retinal Pericyte Apoptosis in Diabetic Rats and Its Active Compound, Chlorogenic Acid Inhibits AGE Formation and AGE/RAGE Interaction

    Directory of Open Access Journals (Sweden)

    Junghyun Kim

    2016-09-01

    Full Text Available Retinal capillary cell loss is a hallmark of early diabetic retinal changes. Advanced glycation end products (AGEs are believed to contribute to retinal microvascular cell loss in diabetic retinopathy. In this study, the protective effects of Aster koraiensis extract (AKE against damage to retinal vascular cells were investigated in streptozotocin (STZ-induced diabetic rats. To examine this issue further, AGE accumulation, nuclear factor-kappaB (NF-κB and inducible nitric oxide synthase (iNOS were investigated using retinal trypsin digests from streptozotocin-induced diabetic rats. In the diabetic rats, TUNEL (Terminal deoxynucleotidyl transferase mediated dUTP Nick End Labeling-positive retinal microvascular cells were markedly increased. Immunohistochemical studies revealed that AGEs were accumulated within the retinal microvascular cells, and this accumulation paralleled the activation of NF-κB and the expression of iNOS in the diabetic rats. However, AKE prevented retinal microvascular cell apoptosis through the inhibition of AGE accumulation and NF-κB activation. Moreover, to determine the active compounds of AKE, two major compounds, chlorogenic acid and 3,5-di-O-caffeoylquinic acid, were tested in an in vitro assay. Among these compounds, chlorogenic acid significantly reduced AGE formation as well as AGE/RAGE (receptor for AGEs binding activity. These results suggest that AKE, particularly chlorogenic acid, is useful in inhibiting AGE accumulation in retinal vessels and exerts a preventive effect against the injuries of diabetic retinal vascular cells.

  14. A ratiometric fluorescent quantum dots based biosensor for organophosphorus pesticides detection by inner-filter effect.

    Science.gov (United States)

    Yan, Xu; Li, Hongxia; Han, Xiaosong; Su, Xingguang

    2015-12-15

    In this work, we develop a novel and sensitive sensor for the detection of organophosphorus pesticides based on the inner-filter effect (IFE) between gold nanoparticles (AuNPs) and ratiometric fluorescent quantum dots (RF-QDs). The RF-QDs has been designed by hybridizing two differently colored CdTe QDs, in which the red emissive QDs entrapped in the silica sphere acting as the reference signal, and the green emissive QDs covalently attached on the silica surface serving as the response signal.The fluorescence of RF-QDs could be quenched by AuNPs based on IFE. Protamine could effectively turn on the fluorescence due to the electrostatic attraction between protamine and AuNPs. Trypsin can easily hydrolyze protamine, leading to the quench of the fluorescence. Then, the fluorescence could be recovered again by the addition of parathion-methyl (PM) which could inhibit the activity of trypsin. By measuring the fluorescence of RF-QDs, the inhibition efficiency of PM to trypsin activity was evaluated. Under the optimized conditions, the inhibition efficiency was proportional to the logarithm of PM concentration in the range of 0.04-400 ng mL(-1), with a detection limit of 0.018 ng mL(-1). Furthermore, the simple and convenient method had been used for PM detection in environmental and agricultural samples with satisfactory results. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Prevalence of behavioral inhibition among preschool aged children in Tehran, Iran.

    Directory of Open Access Journals (Sweden)

    Alipasha Meysamie

    2014-04-01

    Full Text Available One of the identified risk factors for anxiety disorders in adolescence and adulthood is inhibited behaviors in childhood. The present study sought to examine the relationship between behavioral inhibition with some of the internal (personal and external (family environment factors in a sample of preschool children in kindergartens. In a cross sectional study in 2009, data was collected trough a structured questionnaire completed by parents and teachers in day-care centers. A total of 1403 children were assessed. Analysis was performed through complex sample analysis. The results showed that 7.4% (CI95%= 6.1%-9.1% of children according to parents' and 8.1% (CI95%= 6%- 10.7% according to teachers' evaluation classified as behaviorally inhibited. The higher levels of behavioral inhibition were shown by girls, first children, single parent families and older children. Birth year before 2004, birth rank, living in a single parent family and maternal level of education were independent predictors for behavioral inhibition in logistic regression modeling. There is relatively high prevalence of inhibited behaviors among Iranian children. Further examination of diagnosed children with behavioral inhibition by experienced psychiatrists is needed. Also establishing consultation centers for behaviorally inhibited children and instructing their parents and teachers are recommended.

  16. Effect of Aging on Motor Inhibition during Action Preparation under Sensory Conflict

    Science.gov (United States)

    Duque, Julie; Petitjean, Charlotte; Swinnen, Stephan P.

    2016-01-01

    Motor behaviors often require refraining from selecting options that may be part of the repertoire of natural response tendencies but that are in conflict with ongoing goals. The presence of sensory conflict has a behavioral cost but the latter can be attenuated in contexts where control processes are recruited because conflict is expected in advance, producing a behavioral gain compared to contexts where conflict occurs in a less predictable way. In the present study, we investigated the corticospinal correlates of these behavioral effects (both conflict-driven cost and context-related gain). To do so, we measured motor-evoked potentials (MEPs) elicited by transcranial magnetic stimulation (TMS) over the primary motor cortex (M1) of young and healthy older adults performing the Eriksen Flanker Task. Subjects performed button-presses according to a central arrow, flanked by irrelevant arrows pointing in the same (congruent trial) or opposite direction (incongruent trial). Conflict expectation was manipulated by changing the probability of congruent and incongruent trials in a given block. It was either high (mostly incongruent blocks, MIB, 80% incongruent trials) or low (mostly congruent blocks, MCB, 80% congruent). The MEP data indicate that the conflict-driven behavioral cost is associated with a strong increase in inappropriate motor activity regardless of the age of individuals, as revealed by larger MEPs in the non-responding muscle in incongruent than in congruent trials. However, this aberrant facilitation disappeared in both groups of subjects when conflict could be anticipated (i.e., in the MIBs) compared to when it occurred in a less predictably way (MCBs), probably allowing the behavioral gain observed in both the young and the older individuals. Hence, the ability to overcome and anticipate conflict was surprisingly preserved in the older adults. Nevertheless, some control processes are likely to evolve with age because the behavioral gain observed in

  17. Pharmacokinetics and effects on serum cholinesterase activities of organophosphorus pesticides acephate and chlorpyrifos in chimeric mice transplanted with human hepatocytes.

    Science.gov (United States)

    Suemizu, Hiroshi; Sota, Shigeto; Kuronuma, Miyuki; Shimizu, Makiko; Yamazaki, Hiroshi

    2014-11-01

    Organophosphorus pesticides acephate and chlorpyrifos in foods have potential to impact human health. The aim of the current study was to investigate the pharmacokinetics of acephate and chlorpyrifos orally administered at lowest-observed-adverse-effect-level doses in chimeric mice transplanted with human hepatocytes. Absorbed acephate and its metabolite methamidophos were detected in serum from wild type mice and chimeric mice orally administered 150mg/kg. Approximately 70% inhibition of cholinesterase was evident in plasma of chimeric mice with humanized liver (which have higher serum cholinesterase activities than wild type mice) 1day after oral administrations of acephate. Adjusted animal biomonitoring equivalents from chimeric mice studies were scaled to human biomonitoring equivalents using known species allometric scaling factors and in vitro metabolic clearance data with a simple physiologically based pharmacokinetic (PBPK) model. Estimated plasma concentrations of acephate and chlorpyrifos in humans were consistent with reported concentrations. Acephate cleared similarly in humans and chimeric mice but accidental/incidental overdose levels of chlorpyrifos cleared (dependent on liver metabolism) more slowly from plasma in humans than it did in mice. The data presented here illustrate how chimeric mice transplanted with human hepatocytes in combination with a simple PBPK model can assist evaluations of toxicological potential of organophosphorus pesticides. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Novel organophosphorus scaffolds of urease inhibitors obtained by substitution of Morita-Baylis-Hillman adducts with phosphorus nucleophiles.

    Science.gov (United States)

    Ntatsopoulos, Vassilis; Vassiliou, Stamatia; Macegoniuk, Katarzyna; Berlicki, Łukasz; Mucha, Artur

    2017-06-16

    The reactivity of Morita-Baylis-Hillman allyl acetates was employed to introduce phosphorus-containing functionalities to the side chain of the cinnamic acid conjugated system by nucleophilic displacement. The proximity of two acidic groups, the carboxylate and phosphonate/phosphinate groups, was necessary to form interactions in the active site of urease by recently described inhibitor frameworks. Several organophosphorus scaffolds were obtained and screened for inhibition of the bacterial urease, an enzyme that is essential for survival of urinary and gastrointestinal tract pathogens. α-Substituted phosphonomethyl- and 2-phosphonoethyl-cinnamate appeared to be the most potent and were further optimized. As a result, one of the most potent organophosphorus inhibitors of urease, α-phosphonomethyl-p-methylcinnamic acid, was identified, with K i  = 0.6 μM for Sporosarcina pasteurii urease. High complementarity to the enzyme active site was achieved with this structure, as any further modifications significantly decreased its affinity. Finally, this work describes the challenges faced in developing ligands for urease. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  19. Catalytic Characteristics of New Antibacterials Based on Hexahistidine-Containing Organophosphorus Hydrolase

    Directory of Open Access Journals (Sweden)

    Olga Maslova

    2017-09-01

    Full Text Available Catalytic characteristics of hexahistidine-containing organophosphorus hydrolase (His6-OPH and its enzyme-polyelectrolyte complexes with poly-l-glutamic acid or poly-l-aspartic acid (His6-OPH/PLD50, hydrolyzing organophosphorous compounds, and N-acyl homoserine lactones were studied in the presence of various antibiotics (ampicillin, gentamicin, kanamycin, and rifampicin. The antibiotics at concentrations below 1 g·L−1 had a negligible inhibiting effect on the His6-OPH activity. Mixed inhibition of His6-OPH was established for higher antibiotic concentrations, and rifampicin was the most potent inhibitor. Stabilization of the His6-OPH activity was observed in the presence of antibiotics at a concentration of 0.2 g·L−1 during exposure at 25–41 °C. Molecular docking of antibiotics to the surface of His6-OPH dimer revealed the antibiotics binding both to the area near active centers of the enzyme subunits and to the region of contact between subunits of the dimer. Such interactions between antibiotics and His6-OPH were verified with Fourier-transform infrared (FTIR spectroscopy. Considering all the results of the study, the combination of His6-OPH/PLD50 with β-lactam antibiotic ampicillin was established as the optimal one in terms of exhibition and persistence of maximal lactonase activity of the enzyme.

  20. Cholinesterase reactivators and bioscavengers for pre- and post-exposure treatments of organophosphorus poisoning.

    Science.gov (United States)

    Masson, Patrick; Nachon, Florian

    2017-08-01

    Organophosphorus agents (OPs) irreversibly inhibit acetylcholinesterase (AChE) causing a major cholinergic syndrome. The medical counter-measures of OP poisoning have not evolved for the last 30 years with carbamates for pretreatment, pyridinium oximes-based AChE reactivators, antimuscarinic drugs and neuroprotective benzodiazepines for post-exposure treatment. These drugs ensure protection of peripheral nervous system and mitigate acute effects of OP lethal doses. However, they have significant limitations. Pyridostigmine and oximes do not protect/reactivate central AChE. Oximes poorly reactivate AChE inhibited by phosphoramidates. In addition, current neuroprotectants do not protect the central nervous system shortly after the onset of seizures when brain damage becomes irreversible. New therapeutic approaches for pre- and post-exposure treatments involve detoxification of OP molecules before they reach their molecular targets by administrating catalytic bioscavengers, among them phosphotriesterases are the most promising. Novel generation of broad spectrum reactivators are designed for crossing the blood-brain barrier and reactivate central AChE. This is an article for the special issue XVth International Symposium on Cholinergic Mechanisms. © 2017 International Society for Neurochemistry.

  1. Inhibition of Methylglyoxal-Induced AGEs/RAGE Expression Contributes to Dermal Protection by N-Acetyl-L-Cysteine

    Directory of Open Access Journals (Sweden)

    Chun-tao Yang

    2017-02-01

    Full Text Available Background/Aim: Accumulation of advanced glycation end products (AGEs is a major cause of diabetes mellitus (DM skin complications. Methylglyoxal (MGO, a reactive dicarbonyl compound, is a crucial intermediate of AGEs generation. N-acetyl-L-cysteine (NAC, an active ingredient of some medicines, can induce endogenous GSH and hydrogen sulfide generation, and set off a condensation reaction with MGO. However, there is rare evidence to show NAC can alleviate DM-induced skin injury through inhibition of AGEs generation or toxicity. The present study aimed to observe the effects of NAC on MGO-induced inflammatory injury and investigate the roles of AGEs and its receptor (RAGE in NAC’s dermal protection in human HaCaT keratinocytes. Methods: The cells were exposed to MGO to simulate a high MGO status in diabetic blood or tissues. The content of AGEs in serum or cell medium was measured with ELISA. The protective effects of NAC against MGO-induce injury were evaluated by administration before MGO one hour, in virtue of cell viability, mitochondrial membrane potential, inflammation reaction, nuclear factor (NF-κB activation, matrix metalloproteinase (MMP-9 expression, as well as cellular behavioral function. Results: We found the AGEs levels of patients with DM were elevated comparing with healthy volunteers. The in vitro AGEs generation was also able to be enhanced by the exposure of HaCaT cells to MGO, which reduced dose-dependently cellular viability, damaged mitochondrial function, triggered secretion of interleukin (IL-6 and IL-8, activated NF-κB and upregulated MMP-9 expression. Furthermore, the exposure caused cellular adhesion and migration dysfunction, as well as collagen type I inhibition. Importantly, before the exposure to MGO, the preconditioning with NAC significantly attenuated MGO-induced AGEs generation, improved cellular viability and mitochondrial function, partially reversed the overexpression of proinflammatory factors and MMP-9

  2. The brain imaging study of the organophosphorus pesticides poisoning

    International Nuclear Information System (INIS)

    Yang Yanmei; Liu Huaijun; Li Shuling; Wang Yongsheng; Huang Boyuan; Chi Cen; Shi Zhenyang; Cui Caixia; Zhou Lixia; Liu Runtian

    2004-01-01

    Objective: To summarize the CT and MR imaging findings in acute organophosphorus pesticides poisoning patients, and to improve the early diagnostic ability. Methods: The imaging of 34 patients of organophosphorus pesticides poisoning was analyzed, the poisons were all taken orally. The pesticides included methamidophos (12 cases), omethoate (15 cases), DDV (3 cases), and methylparathion (4 cases). According to the diagnosis and classification diagnosis criterion of acute organophosphorus pesticides poisoning, the patients were divided into two groups: mild or moderate grade group (24 cases) and severe grade group (10 cases). The relationship between the clinic grade and CT and MRI findings was studied. Results: in the severe grade group, 4 patients showed brain edema, presenting as sulcus and fissure flattened or disappeared, and ventricles and cisterns narrowed or closed 2-3 days after poisoning. In 3 patients 3 days to 3 months after poisoning, bilateral basal ganglion and cerebral cortex showed prolonged T 1 and T 2 signals, and high signal intensity was detected on FLAIR, and bilateral basal ganglion low density was revealed on CT. T 1 relaxation was shortened, T 2 WI and FLAIR imaging showed high signal intensity in 1 patient. The imaging of 1 patient 6 months after poisoning showed the cerebral sulcus, fissure and ventricle were enlarged. CT and MRI in the mild or moderate group were normal. By the Fisher's exact probabilities test, the imaging exhibition difference between the severe grade and mild or moderate grade patients was significant. Conclusion: The CT and MRI can reflect the brain injury after poisoning, and the imaging exhibitions were various. The imaging information can provide credible foundation for the therapy for lightening the brain edema and nourishing the brain cell

  3. Electrophysiologic changes following treatment with organophosphorus-induced delayed neuropathy-producing agents in the adult hen.

    Science.gov (United States)

    Robertson, D G; Schwab, B W; Sills, R D; Richardson, R J; Anderson, R J

    1987-03-15

    Although clinical, pathological, and biochemical effects of organophosphorus-induced delayed neuropathy (OPIDN) have been intensively investigated in the adult hen, detailed electrophysiological studies are lacking. Adult white leghorn hens were treated with a single oral dose of either 30 mg/kg tri-2-cresyl phosphate (TOCP), 750 mg/kg TOCP, 4 mg/kg di-n-butyl-2,2-dichlorovinyl phosphate (DBCV), or 30 mg/kg di-n-butyl-2,2-dichlorovinyl phosphinate (DBCV-P). The 750 mg/kg TOCP and DBCV, but not the 30 mg/kg TOCP and DBCV-P, treatments resulted in clinical signs of OPIDN and mild to marked damage of the tibial nerve 21 days after dose. Twenty-four hr lymphocyte neurotoxic esterase (NTE) inhibition was used as an index of brain NTE inhibition for the various organophosphorus compound (OP) treatment. Twenty-four hr lymphocyte NTE inhibition for 30 mg/kg TOCP, 750 mg/kg TOCP, DBCV, and DBCV-P was 54.1, 87.1, 84.8, and 68.3%, respectively. Twenty-one days after dose, the TOCP-treated hens exhibited some abnormalities in conduction velocity and action potential duration in the tibial or sciatic nerves. No abnormalities were observed in action potential parameters of either the DBCV or DBCV-P treatments. Neurotoxic OP (TOCP and DBCV) treatment resulted in decreased refractoriness in the tibial nerve, increased refractoriness in the sciatic nerve, and elevated strength duration threshold for both nerves. These changes were not present in nerves from DBCV-P (a non-neurotoxic NTE inhibitor)-treated hens. These results suggest that refractory period and strength duration abnormalities in peripheral nerve correlate well with the production of OPIDN and are evident without coincident clinical signs or histopathology.

  4. Multifunctional organophosphorus extractants: a status report on development and applications

    International Nuclear Information System (INIS)

    Schulz, W.W.; Horwitz, E.P.

    1988-01-01

    Up-to-date state of the development of science and technology of multifunctional organophosphorus extractants is considered. The detailed classification of these extractants is presented. They attracted pasticular interest because of affinity of some bifunctional phosphonates, phosphine oxides, carbamoylalkylphosphonates to trivalent Am, tetravalent and hexavalent actinides, trivalent lanthanides in strong mineral acids, and because of ability of some alkylpyrophosphoric acids to extract effectively U(4) from concentrated solutions of phosphoric acid. Application of these extractants for analytic purposes and in the field of nuclear technology is considered

  5. Organophosphorus pesticides decrease M2 muscarinic receptor function in guinea pig airway nerves via indirect mechanisms.

    Directory of Open Access Journals (Sweden)

    Becky J Proskocil

    Full Text Available BACKGROUND: Epidemiological studies link organophosphorus pesticide (OP exposures to asthma, and we have shown that the OPs chlorpyrifos, diazinon and parathion cause airway hyperreactivity in guinea pigs 24 hr after a single subcutaneous injection. OP-induced airway hyperreactivity involves M2 muscarinic receptor dysfunction on airway nerves independent of acetylcholinesterase (AChE inhibition, but how OPs inhibit neuronal M2 receptors in airways is not known. In the central nervous system, OPs interact directly with neurons to alter muscarinic receptor function or expression; therefore, in this study we tested whether the OP parathion or its oxon metabolite, paraoxon, might decrease M2 receptor function on peripheral neurons via similar direct mechanisms. METHODOLOGY/PRINCIPAL FINDINGS: Intravenous administration of paraoxon, but not parathion, caused acute frequency-dependent potentiation of vagally-induced bronchoconstriction and increased electrical field stimulation (EFS-induced contractions in isolated trachea independent of AChE inhibition. However, paraoxon had no effect on vagally-induced bradycardia in intact guinea pigs or EFS-induced contractions in isolated ileum, suggesting mechanisms other than pharmacologic antagonism of M2 receptors. Paraoxon did not alter M2 receptor expression in cultured cells at the mRNA or protein level as determined by quantitative RT-PCR and radio-ligand binding assays, respectively. Additionally, a biotin-labeled fluorophosphonate, which was used as a probe to identify molecular targets phosphorylated by OPs, did not phosphorylate proteins in guinea pig cardiac membranes that were recognized by M2 receptor antibodies. CONCLUSIONS/SIGNIFICANCE: These data indicate that neither direct pharmacologic antagonism nor downregulated expression of M2 receptors contributes to OP inhibition of M2 function in airway nerves, adding to the growing evidence of non-cholinergic mechanisms of OP neurotoxicity.

  6. Determinants of Organophosphorus Pesticide Urinary Metabolite Levels in Young Children Living in an Agricultural Community

    Directory of Open Access Journals (Sweden)

    Brenda Eskenazi

    2011-04-01

    Full Text Available Organophosphorus (OP pesticides are used in agriculture and several are registered for home use. As young children age they may experience different pesticide exposures due to varying diet, behavior, and other factors. We measured six OP dialkylphosphate (DAP metabolites (three dimethyl alkylphosphates (DMAP and three diethyl alkylphosphates (DEAP in urine samples collected from ~400 children living in an agricultural community when they were 6, 12, and 24 months old. We examined bivariate associations between DAP metabolite levels and determinants such as age, diet, season, and parent occupation. To evaluate independent impacts, we then used generalized linear mixed multivariable models including interaction terms with age. The final models indicated that DMAP metabolite levels increased with age. DMAP levels were also positively associated with daily servings of produce at 6- and 24-months. Among the 6-month olds, DMAP metabolite levels were higher when samples were collected during the summer/spring versus the winter/fall months. Among the 12-month olds, DMAP and DEAP metabolites were higher when children lived ≤60 meters from an agricultural field. Among the 24-month-olds, DEAP metabolite levels were higher during the summer/spring months. Our findings suggest that there are multiple determinants of OP pesticide exposures, notably dietary intake and temporal and spatial proximity to agricultural use. The impact of these determinants varied by age and class of DAP metabolite.

  7. Effects on atrial fibrillation in aged hypertensive rats by Ca(2+)-activated K(+) channel inhibition

    DEFF Research Database (Denmark)

    Diness, Jonas Goldin; Skibsbye, Lasse; Jespersen, Thomas

    2011-01-01

    We have shown previously that inhibition of small conductance Ca(2+)-activated K(+) (SK) channels is antiarrhythmic in models of acutely induced atrial fibrillation (AF). These models, however, do not take into account that AF derives from a wide range of predisposing factors, the most prevalent ...

  8. [Meta-analysis of association between organophosphorus pesticides and aplastic anemia].

    Science.gov (United States)

    Zhang, Ji; Yang, Tubao

    2015-09-01

    To evaluate the association between organophosphorus pesticides and aplastic anemia, and provide scientific evidence for the primary prevention of aplastic anemia. The published papers of case control studies on the association between organophosphorus pesticides and aplastic anemia from January 1990 to August 2014 were collected from Chinese BioMedical Literature Base (CBM), Chinese National Knowledge Infrastructure (CNKI), PubMed and EMBASE. The papers which met the inclusion criteria were evaluated. The pooled odds ratios (OR) and 95% confidence interval (CI) of organophosphorus pesticides were calculated with software Review Manager 5.0. Subgroup analysis were conducted for different population and different usage of organophosphorus pesticides. A total of 9 papers were selected, involving 5 833 subjects (1 404 cases and 4 429 controls). The results showed that organophosphorus pesticides could increase the risk of aplastic anemia (OR=1.97, 95% CI: 1.60-2.44) . Subgroup analysis showed that Asian (OR=2.01, 95% CI: 1.52-2.66) had higher risk of aplastic anemia than American or European (OR=1.93, 95% CI: 1.39-2.67) . Using pure organophosphorus pesticides (OR=2.15, 95% CI: 1.60-2.88) was more prone to cause aplastic anemia than using the mixture of organophosphorus pesticides (OR=1.82, 95% CI: 1.34-2.47). The analysis indicated that organophosphorus pesticides might be a risk factor for aplastic anemia. Reducing organophosphorus pesticides exposure in daily life and industrial or agricultural production could prevent the incidence of aplastic anemia.

  9. Inhibition of advanced glycation endproduct (AGE) rescues against streptozotocin-induced diabetic cardiomyopathy: Role of autophagy and ER stress.

    Science.gov (United States)

    Pei, Zhaohui; Deng, Qinqin; Babcock, Sara A; He, Emily Y; Ren, Jun; Zhang, Yingmei

    2018-03-01

    Diabetes mellitus leads to oxidative stress and contractile dysfunction in the heart. Although several rationales have been speculated, the precise mechanism behind diabetic cardiomyopathy remains elusive. This study was designed to assess the role of inhibition of advanced glycation endproducts (AGE) in streptozotocin (STZ)-induced diabetic cardiac dysfunction. Cardiac contractile function was assessed in normal C57BL/6 and STZ (200mg/kg, single injection and maintained for 2 wks)-induced diabetic mice treated with or without the AGE inhibitor aminoguanidine (50mg/kg/d in drinking water) for 2 weeks using echocardiography and IonOptix MyoCam techniques. Diabetes compromised cardiac contractile function shown as reduced fractional shortening and ejection fraction, enlarged left ventricular end systolic/diastolic diameters, decreased peak shortening, maximal velocity of shortening/relengthening, prolonged shortening and relengthening duration as well as impaired intracellular Ca 2+ homeostasis, the effects of which were alleviated or reversed by aminoguanidine treatment. Diabetes also inhibited autophagy, increased ER stress and phosphorylation of pro-hypertrophic signaling molecules Akt and mTOR, the effect of which was reversed by aminoguanidine. In vitro study revealed that methylglyoxal-derived AGE (MG-AGE) incubation in isolated cardiomyocytes promoted oxidation of sarco(endo)plasmic reticulum Ca 2+ -ATPase (SERCA2a) and production of superoxide, the effects of which were negated by the autophagy inducer rapamycin, the ER stress chaperone TUDCA or the antioxidant N-acetylcysteine. Taken together, these data revealed that inhibition of AGE formation rescues against experimental diabetes-induced cardiac remodeling and contractile dysfunction possible through regulation of autophagy and ER stress. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Activity of Ca(2+,Mg(2+-ATPase of sarcoplasmic reticulum and contraction strength of the frog skeletal muscles under the effect of organophosphorus insecticides

    Directory of Open Access Journals (Sweden)

    D. M. Nozdrenko

    2015-08-01

    Full Text Available The results of an experimental study of organo­phosphorus insecticides, including pirimiphosmethyl, diazinon and chlorpyrifos caused a decline of the contraction properties in m. tibialis anterior fiber bundles of Rana temporaria, as well as sarcoplasmic reticulum Ca2+,Mg2+-ATPase enzymatic activity reduction are outlined in this paper. Concentration-dependent strengths response diminishing in isolated skeletal muscle fiber bundles as a result of non-cholinergic influence of organophosphorus insecticides were found. A decrease of Ca2+,Mg2+-ATPase enzymatic activity in sarcoplasmic reticulum was observed after administration of each insecticide. The most significant inhibition of this enzyme was observed when using chlorpyrifos.

  11. Acute myocardial infarction: Can it be a complication of acute organophosphorus compound poisoning?

    Directory of Open Access Journals (Sweden)

    P Joshi

    2013-01-01

    Full Text Available Organophosphorus compounds are used as pesticides and represent a common cause of poisoning in developing countries including India due to their widespread availability and use. Toxicity due to these agents can affect many organs including heart. Here, we report a case of acute organophosphorus poisoning (parathion, followed by acute myocardial infarction; documented by clinical features, electrocardiographic changes, and elevated cardiac enzymes. Myocardial infarction has been rarely reported with organophosphorus compounds exposure, thus awareness of this complication can reduce morbidity and mortality.

  12. Grape Seed Proanthocyanidin Extract Prevents Ovarian Aging by Inhibiting Oxidative Stress in the Hens

    Directory of Open Access Journals (Sweden)

    Xingting Liu

    2018-01-01

    Full Text Available Oxidative stress is an important inducement in ovarian aging which results in fecundity decline in human and diverse animals. As a potent antioxidant, grape seed proanthocyanidin extract (GSPE was investigated to ameliorate chicken ovarian aging in this study. Firstly, ovarian antioxidant capacity of hens at different ages (90, 150, 280, and 580 days old was compared to elucidate its age-related changes. Subsequently, a D-gal-induced (2.5 mg/mL aging ovarian model was established and the cultured ovarian tissues were treated with GSPE at 5 μg/mL for 72 h to evaluate the putative attenuating effects of GSPE on ovarian aging. Meanwhile, ovaries of D280 (young and D580 (old were treated with GSPE for 72 h in culture to verify the protective effects of GSPE on natural aging ovary. The results showed that GSPE could rescue the antioxidant capacity decline by increasing the antioxidase activities and their gene expression in either D-gal-induced or natural aging ovaries. Moreover, GSPE could maintain the homeostasis between cell proliferation and apoptosis in the D-gal-induced and natural aging ovaries, as well as alleviate D-gal-induced nucleus chromatin condensation in the ovarian granulosa cells. In conclusion, GSPE treatment can effectively prevent the ovarian aging process in hens by reducing oxidative stress.

  13. Effects of age and gender on neural networks of motor response inhibition: from adolescence to mid-adulthood.

    Science.gov (United States)

    Rubia, Katya; Lim, Lena; Ecker, Christine; Halari, Rozmin; Giampietro, Vincent; Simmons, Andrew; Brammer, Michael; Smith, Anna

    2013-12-01

    Functional inhibitory neural networks mature progressively with age. However, nothing is known about the impact of gender on their development. This study employed functional magnetic resonance imaging (fMRI) to investigate the effects of age, sex, and sex by age interactions on the brain activation of 63 healthy males and females, between 13 and 38 years, performing a Stop task. Increasing age was associated with progressively increased activation in typical response inhibition areas of right inferior and dorsolateral prefrontal and temporo-parietal regions. Females showed significantly enhanced activation in left inferior and superior frontal and striatal regions relative to males, while males showed increased activation relative to females in right inferior and superior parietal areas. Importantly, left frontal and striatal areas that showed increased activation in females, also showed significantly increased functional maturation in females relative to males, while the right inferior parietal activation that was increased in males showed significantly increased functional maturation relative to females. The findings demonstrate for the first time that sex-dimorphic activation patterns of enhanced left fronto-striatal activation in females and enhanced right parietal activation in males during motor inhibition appear to be the result of underlying gender differences in the functional maturation of these brain regions. © 2013. Published by Elsevier Inc. All rights reserved.

  14. Resveratrol Ameliorates Aging-Related Metabolic Phenotypes by Inhibiting cAMP Phosphodiesterases

    OpenAIRE

    Park, Sung-Jun; Ahmad, Faiyaz; Philp, Andrew; Baar, Keith; Williams, Tishan; Luo, Haibin; Ke, Hengming; Rehmann, Holger; Taussig, Ronald; Brown, Alexandra L.; Kim, Myung K.; Beaven, Michael A.; Burgin, Alex B.; Manganiello, Vincent; Chung, Jay H.

    2012-01-01

    Resveratrol, a polyphenol in red wine, has been reported as a calorie restriction mimetic with potential antiaging and antidiabetogenic properties. It is widely consumed as a nutritional supplement, but its mechanism of action remains a mystery. Here, we report that the metabolic effects of resveratrol result from competitive inhibition of cAMP-degrading phosphodiesterases, leading to elevated cAMP levels. The resulting activation of Epac1, a cAMP effector protein, increases intracellular Ca2...

  15. Edaravone Protected Human Brain Microvascular Endothelial Cells from Methylglyoxal-Induced Injury by Inhibiting AGEs/RAGE/Oxidative Stress

    Science.gov (United States)

    Li, Wenlu; Xu, Hongjiao; Hu, Yangmin; He, Ping; Ni, Zhenzhen; Xu, Huimin; Zhang, Zhongmiao; Dai, Haibin

    2013-01-01

    Subjects with diabetes experience an increased risk of cerebrovascular disease and stroke compared with nondiabetic age-matched individuals. Increased formation of reactive physiological dicarbonyl compound methylglyoxal (MGO) seems to be implicated in the development of diabetic vascular complication due to its protein glycation and oxidative stress effect. Edaravone, a novel radical scavenger, has been reported to display the advantageous effects on ischemic stroke both in animals and clinical trials; however, little is known about whether edaravone has protective effects on diabetic cerebrovascular injury. Using cultured human brain microvascular endothelial cells (HBMEC), protective effects of edaravone on MGO and MGO enhancing oxygen-glucose deprivation (OGD) induced injury were investigated. Cell injury was measured by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) formation, cell account, lactate dehydrogenase (LDH) release and Rhodamine 123 staining. Advanced glycation end-products (AGEs) formation and receptor for advanced glycation end-products (RAGE) expression were measured by western blotting. Cellular oxidative stress was measured by reactive oxygen species (ROS) release. Treatment of MGO for 24 h significantly induced HBMEC injury, which was inhibited by pretreatment of edaravone from 10–100 µmol/l. What’s more, treatment of MGO enhanced AGEs accumulation, RAGE expression and ROS release in the cultured HBMEC, which were inhibited by 100 µmol/l edaravone. Finally, treatment of MGO for 24 h and then followed by 3 h OGD insult significantly enhanced cell injury when compared with OGD insult only, which was also protected by 100 µmol/l edaravone. Thus, edaravone protected HBMEC from MGO and MGO enhancing OGD-induced injury by inhibiting AGEs/RAGE/oxidative stress. PMID:24098758

  16. Edaravone protected human brain microvascular endothelial cells from methylglyoxal-induced injury by inhibiting AGEs/RAGE/oxidative stress.

    Directory of Open Access Journals (Sweden)

    Wenlu Li

    Full Text Available Subjects with diabetes experience an increased risk of cerebrovascular disease and stroke compared with nondiabetic age-matched individuals. Increased formation of reactive physiological dicarbonyl compound methylglyoxal (MGO seems to be implicated in the development of diabetic vascular complication due to its protein glycation and oxidative stress effect. Edaravone, a novel radical scavenger, has been reported to display the advantageous effects on ischemic stroke both in animals and clinical trials; however, little is known about whether edaravone has protective effects on diabetic cerebrovascular injury. Using cultured human brain microvascular endothelial cells (HBMEC, protective effects of edaravone on MGO and MGO enhancing oxygen-glucose deprivation (OGD induced injury were investigated. Cell injury was measured by 3-(4,5-Dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT formation, cell account, lactate dehydrogenase (LDH release and Rhodamine 123 staining. Advanced glycation end-products (AGEs formation and receptor for advanced glycation end-products (RAGE expression were measured by western blotting. Cellular oxidative stress was measured by reactive oxygen species (ROS release. Treatment of MGO for 24 h significantly induced HBMEC injury, which was inhibited by pretreatment of edaravone from 10-100 µmol/l. What's more, treatment of MGO enhanced AGEs accumulation, RAGE expression and ROS release in the cultured HBMEC, which were inhibited by 100 µmol/l edaravone. Finally, treatment of MGO for 24 h and then followed by 3 h OGD insult significantly enhanced cell injury when compared with OGD insult only, which was also protected by 100 µmol/l edaravone. Thus, edaravone protected HBMEC from MGO and MGO enhancing OGD-induced injury by inhibiting AGEs/RAGE/oxidative stress.

  17. Effect of two organophosphorus insecticides on the growth, respiration and (/sup 14/C)-glucose metabolism of Azobacter chroococcum Beij

    Energy Technology Data Exchange (ETDEWEB)

    Balasubramanian, A; Narayanan, R [Tamil Nadu Agricultural Univ., Coimbatore (India)

    1980-01-01

    The two organophosphorus insecticides, commonly applied to soil, viz., disulfoton (0,0-diethyl S-2-ethyl thio ethyl phosphorodithioate) and fensulfothion (0,0-diethyl 0-4-methyl sulphinyl phenyl phosphorothioate) did not affect the in vitro growth of Azotobacter chroococcum Beij., the free-living, nitrogen fixing soil bacterium, at 2 ppm (lower level), while the normal dose (5 ppm) and the higher level (10 ppm) suppressed the growth. Respiration of the organism (glucose oxidation) was adversely affected by the insecticides in the growth medium and the inhibition increased with the concentration of the chemical. Both the insecticides suppressed the assimilation of (/sup 14/C)-glucose in the cold-TCA soluble, hot-TCA soluble fractions and insoluble residue of the cells whereas the /sup 14/C-incorporation in the alcohol soluble and alcohol-ether soluble fractions was enhanced indicating that the insecticides considerably altered the glucose metabolism of the bacterium.

  18. Effect of two organophosphorus insecticides on the growth, respiration and (14C)-glucose metabolism of Azobacter chroococcum Beij

    International Nuclear Information System (INIS)

    Balasubramanian, A.; Narayanan, R.

    1980-01-01

    The two organophosphorus insecticides, commonly applied to soil, viz., disulfoton (0,0-diethyl S-2-ethyl thio ethyl phosphorodithioate) and fensulfothion (0,0-diethyl 0-4-methyl sulphinyl phenyl phosphorothioate) did not affect the in vitro growth of Azotobacter chroococcum Beij., the free-living, nitrogen fixing soil bacterium, at 2 ppm (lower level), while the normal dose (5 ppm) and the higher level (10 ppm) suppressed the growth. Respiration of the organism (glucose oxidation) was adversely affected by the insecticides in the growth medium and the inhibition increased with the concentration of the chemical. Both the insecticides suppressed the assimilation of ( 14 C)-glucose in the cold-TCA soluble, hot-TCA soluble fractions and insoluble residue of the cells whereas the 14 C-incorporation in the alcohol soluble and alcohol-ether soluble fractions was enhanced indicating that the insecticides considerably altered the glucose metabolism of the bacterium. (author)

  19. Organophosphorus pesticides effect on early stages of the axolotl Ambystoma mexicanum (Amphibia: Caudata).

    Science.gov (United States)

    Robles-Mendoza, C; García-Basilio, C; Cram-Heydrich, S; Hernández-Quiroz, M; Vanegas-Pérez, C

    2009-02-01

    Ambystoma mexicanum is an endemic salamander of Xochimilco, a wetland of the basin of Mexico valley. Nowadays, axolotl populations are decreasing due environmental stressors. Particularly, studies about organophosphorus pesticides (OPPs; i.e. chlorpyrifos and malathion) toxicity are of great importance due to their intensive use in agricultural activities in Xochimilco. Thus, the aim of this study was to evaluate under controlled conditions the toxicity of chlorpyrifos (CPF) and malathion (MLT) on embryos and larvae (stage 44 and 54) of A. mexicanum. Embryos and larvae were exposure 96h from 0.5 to 3mg CPFL(-1) and from 10 to 30mg MLTL(-1) in independent tests. Embryos at the end of this period were maintained 9d without pesticide in order to identify possible recuperation. Differences obtained in mortality, hatching success, development, morphological abnormalities, behaviour and activity, suggest that toxicity of CPF and MLT differs in embryos and larval stages. Embryos were less sensitive to OPPs acute exposure than axolotl larvae; additionally, toxicity of CPF in larval stages was greater than MLT. On the other hand, data obtained in axolotl embryos during the period of recuperation to CPF in particular as delay and inhibition of development, malformations and success of hatching, indicated that these responses turned out more sensitive than mortality. This study allowed to identify the toxicological potential of OPPs on early developmental stages of A. mexicanum and it is a valuable contribution for the future management of the axolotl wild population.

  20. Aging-associated oxidative stress inhibits liver progenitor cell activation in mice.

    Science.gov (United States)

    Cheng, Yiji; Wang, Xue; Wang, Bei; Zhou, Hong; Dang, Shipeng; Shi, Yufang; Hao, Li; Luo, Qingquan; Jin, Min; Zhou, Qianjun; Zhang, Yanyun

    2017-04-29

    Recent studies have discovered aging-associated changes of adult stem cells in various tissues and organs, which potentially contribute to the organismal aging. However, aging-associated changes of liver progenitor cells (LPCs) remain elusive. Employing young (2-month-old) and old (24-month-old) mice, we found diverse novel alterations in LPC activation during aging. LPCs in young mice could be activated and proliferate upon liver injury, whereas the counterparts in old mice failed to respond and proliferate, leading to the impaired liver regeneration. Surprisingly, isolated LPCs from young and old mice did not exhibit significant difference in their clonogenic and proliferative capacity. Later, we uncovered that the decreased activation and proliferation of LPCs were due to excessive reactive oxygen species produced by neutrophils infiltrated into niche, which was resulted from chemokine production from activated hepatic stellate cells during aging. This study demonstrates aging-associated changes in LPC activation and reveals critical roles for the stem cell niche, including neutrophils and hepatic stellate cells, in the negative regulation of LPCs during aging.

  1. Levels of organophosphorus pesticides in medicinal plants commonly consumed in Iran

    Directory of Open Access Journals (Sweden)

    Sarkhail Parisa

    2012-08-01

    Full Text Available Abstract The frequent occurrence of pesticide residues in herbal materials was indicated by previous studies. In this study, the concentration of some of the organophosphorus pesticides including parathion, malathion, diazinon and pirimiphos methyl in different kinds of medicinal plants were determined. The samples were collected randomly from ten local markets of different areas of Iran. At the detection limit of 0.5 ng g-1, parathion and pirimiphos methyl were not detected in any of the samples. Some amounts of malathion and diazinon were found in Zataria, Matricaria chamomile, Spearmint and Cumin Seed samples while, the concentrations of target organophosphorus pesticides in Borage samples were below the detection limits of the methods which could be a result of intensive transformation of organophosphorus pesticides by Borage. In addition the organophosphorus pesticides were detected in all of the samples below the maximum residue levels (MRLs proposed by the international organizations.

  2. UPTAKE AND PHYTOTRANSFORMATION OF ORGANOPHOSPHORUS PESTICIDES BY AXENICALLY CULTIVATED AQUATIC PLANTS

    Science.gov (United States)

    The uptake and phytotransformation of organophosphorus (OP) pesticides (malathion, demeton-S-methyl, and crufomate) was investigated in vitro using the axenically aquatic cultivated plants parrot feather (Myriophyllum aquaticum), duckweed (Spirodela oligorrhiza L.), and elodea (E...

  3. Surface Chemistry of Enzymes for Detection and Decontamination of Organophosphorus Compounds

    National Research Council Canada - National Science Library

    Leblanc, Roger

    2003-01-01

    ...), organophosphorus acid hydrolase (OPH), and covalent bonding of the enzyme onto the substrate. Results are encouraging and the studied enzymes form stable monolayers at the interface and can be transferred on to the solid substrate...

  4. Suicidal Death due to Organophosphorus Compound Poisoning ─ an Experience of 67 Cases

    Directory of Open Access Journals (Sweden)

    Nashid Tabassum Khan

    2016-05-01

    Full Text Available Background: Bangladesh is an agro-based country. Suicide by agrochemical compounds are increasing day by day in this country. Organophosphorus compounds (OPC are commonly used for suicide. Mostly these are used for suicidal purpose in rural areas in our country due to low cost, toxicity and availability. Objective: To find out the relationship of age and sex variation along with the causes that influenced different income group people to ingest OPC for committing suicide. Materials and Methods: This study was conducted in the Department of Forensic Medicine, Dhaka Medical College during January to December 2010. Data were collected at the time of autopsy and from postmortem examination report of viscera. Viscera were preserved and sent to the Chief Chemical Examiner’s Office, Dhaka for toxicological analysis. Results: In this study, middle aged subjects (20–30 years were found to commit suicide using OPC in comparison to other age groups. Among the cases male were 57% and female 43%. Poverty was found as the most common cause (20% of OPC poisoning. Conclusion: Poverty is the leading cause of death of OPC poisoning followed by failure in love and adultery. Business failure, unhappiness in conjugal life, demand for dowry and violence against women are other causes to commit suicide by OPC.

  5. Modulation of Immune Response by Organophosphorus Pesticides: Fishes as a Potential Model in Immunotoxicology

    Science.gov (United States)

    Díaz-Resendiz, K. J. G.; Toledo-Ibarra, G. A.; Girón-Pérez, M. I.

    2015-01-01

    Immune response is modulated by different substances that are present in the environment. Nevertheless, some of these may cause an immunotoxic effect. In this paper, the effect of organophosphorus pesticides (frequent substances spilled in aquatic ecosystems) on the immune system of fishes and in immunotoxicology is reviewed. Furthermore, some cellular and molecular mechanisms that might be involved in immunoregulation mechanisms of organophosphorus pesticides are discussed. PMID:25973431

  6. Modulation of Immune Response by Organophosphorus Pesticides: Fishes as a Potential Model in Immunotoxicology

    Directory of Open Access Journals (Sweden)

    K. J. G. Díaz-Resendiz

    2015-01-01

    Full Text Available Immune response is modulated by different substances that are present in the environment. Nevertheless, some of these may cause an immunotoxic effect. In this paper, the effect of organophosphorus pesticides (frequent substances spilled in aquatic ecosystems on the immune system of fishes and in immunotoxicology is reviewed. Furthermore, some cellular and molecular mechanisms that might be involved in immunoregulation mechanisms of organophosphorus pesticides are discussed.

  7. Organophosphorus flame retardants and plasticizers in the atmosphere of the North Sea

    International Nuclear Information System (INIS)

    Moeller, Axel; Xie Zhiyong; Caba, Armando; Sturm, Renate; Ebinghaus, Ralf

    2011-01-01

    Air samples collected in the German part of the North Sea from March to July 2010 were investigated for organophosphorus compounds (OPs) being applied as flame retardants and plasticizers. The Σ 8 OPs concentration ranged from 110 to 1400 pg m -3 while tris(2-chloroisopropyl) phosphate (TCPP) dominated all samples with individual concentrations up to 1200 pg m -3 . The highest concentrations were observed in continental air masses showing the high influence of industrialized regions including production sites on atmospheric emissions and concentrations. The occurrence of OPs even in oceanic/Arctic air masses shows that OPs can undergo long-range atmospheric transport. Dry particle-bound deposition fluxes from 9 to 240 ng m -2 d -1 for Σ 8 OPs were estimated leading to a minimum annual flux of 710 ± 580 kg y -1 OPs into the German North Sea. This study presents the first occurrence of OPs in the marine atmosphere together with important information on their long-range transport potential. - Highlights: → Organophosphorus flame retardants are detected for the first time in the marine atmosphere. → Organophosphorus compounds can undergo medium to long-range atmospheric transport. → Western Europe emits organophosphorus compounds to the marine atmosphere. → Marine air levels of organophosphorus flame retardants range up to 1 ng/m 3 . - Organophosphorus flame retardants, in particular tris(2-chloroisopropyl) phosphate, are emitted into the North Sea atmosphere by Western European countries.

  8. Determination of organophosphorus pesticide residues in tomatoes by gas chromatography

    International Nuclear Information System (INIS)

    Souissi, Sihem

    2010-01-01

    Chloropyriphos and malathion are two organophosphorus pesticides from many others pesticides widely used by famers in agriculture .Because of their bad effect on human health, officials standards are set by the international organisations and communities to ensure safer food for consumer .In the same way, scientists over the world are working hard to develop new detection techniques responding to the international requirements. In this study, an ' IAEA-ethylacetate method ', an adaptation of the popular QuEChERS multi residue method, was optimized to analyse chloropyriphos and Malathion residues in tomatoes .Ethyl-Acetate was used as an extraction solvent the PSA was kept for the clean up procedure. GC-NPD is used for samples analysis .The method optimized is specifique, selective with a recovery averaged more than 70 pour cent. A complete validation of the method is necessary to be used for routine analysis.

  9. Fluorescent Chemosensors for Toxic Organophosphorus Pesticides: A Review

    Directory of Open Access Journals (Sweden)

    Kenneth Fletcher

    2010-07-01

    Full Text Available Many organophosphorus (OP based compounds are highly toxic and powerful inhibitors of cholinesterases that generate serious environmental and human health concerns. Organothiophosphates with a thiophosphoryl (P=S functional group constitute a broad class of these widely used pesticides. They are related to the more reactive phosphoryl (P=O organophosphates, which include very lethal nerve agents and chemical warfare agents, such as, VX, Soman and Sarin. Unfortunately, widespread and frequent commercial use of OP-based compounds in agricultural lands has resulted in their presence as residues in crops, livestock, and poultry products and also led to their migration into aquifers. Thus, the design of new sensors with improved analyte selectivity and sensitivity is of paramount importance in this area. Herein, we review recent advances in the development of fluorescent chemosensors for toxic OP pesticides and related compounds. We also discuss challenges and progress towards the design of future chemosensors with dual modes for signal transduction.

  10. Lipofuscin-mediated photic stress inhibits phagocytic activity of ARPE-19 cells; effect of donors' age and antioxidants.

    Science.gov (United States)

    Olchawa, Magdalena M; Furso, Justyna A; Szewczyk, Grzegorz M; Sarna, Tadeusz J

    2017-10-01

    The risk of chronic oxidative stress in the retinal pigment epithelium (RPE) increases with age due to accumulation of the photoreactive age pigment lipofuscin (LFG). Here, we asked whether sublethal and weakly lethal photic stress, induced by irradiation of ARPE-19 cells containing phagocytised LFG, affected the cell specific phagocytic activity, which is critically important for proper functioning and survival of the retina, and if natural antioxidants could modify the observed outcomes. ARPE-19 cells preloaded with LFG isolated from human donors of different age or containing LFG enriched with zeaxanthin and α-tocopherol (LFG-A), were irradiated with blue light. Phagocytosis of fluorescein-5-isothiocyanate (FITC)-labelled photoreceptor outer segments was determined by flow cytometry. Photoreactivity of LFG and LFG-A was analysed by measuring photoconsumption of oxygen and photogeneration of singlet oxygen mediated by the granules. LFG-mediated photic stress in ARPE-19 cells induced significant inhibition of their specific phagocytosis. The inhibitory effect increased with age of LFG donors and was reduced by enrichment of the granules with antioxidants. Oxygen consumption and generation of singlet oxygen induced by the photoexcited LFG increased with donor's age and was partially quenched by antioxidants. Although the phototoxic potential of lipofuscin increased with age, natural antioxidants reduced photoreactivity of LFG and their efficiency to induce oxidative stress. This study has demonstrated, for the first time, that mild oxidative stress, mediated by the age pigment lipofuscin, impairs specific phagocytic activity of RPE, and that natural antioxidants can protect this important cellular function by reducing lipofuscin photoreactivity.

  11. Spatial learning impairment in prepubertal guinea pigs prenatally exposed to the organophosphorus pesticide chlorpyrifos: Toxicological implications

    Science.gov (United States)

    Mamczarz, Jacek; Pescrille, Joseph D.; Gavrushenko, Lisa; Burke, Richard D.; Fawcett, William P.; DeTolla, Louis J.; Chen, Hegang; Pereira, Edna F.R.; Albuquerque, Edson X.

    2017-01-01

    Exposure of the developing brain to chlorpyrifos (CPF), an organophosphorus (OP) pesticide used extensively in agriculture worldwide, has been associated with increased prevalence of cognitive deficits in children, particularly boys. The present study was designed to test the hypothesis that cognitive deficits induced by prenatal exposure to sub-acute doses of CPF can be reproduced in precocial small species. To address this hypothesis, pregnant guinea pigs were injected daily with CPF (25 mg/kg, s.c.) or vehicle (peanut oil) for 10 days starting on presumed gestation day (GD) 53–55. Offspring were born around GD 65, weaned on postnatal day (PND) 20, and subjected to behavioral tests starting around PND 30. On the day of birth, butyrylcholinesterase (BuChE), an OP bioscavenger used as a biomarker of OP exposures, and acetylcholinesterase (AChE), a major molecular target of OP compounds, were significantly inhibited in the blood of CPF-exposed offspring. In their brains, BuChE, but not AChE, was significantly inhibited. Prenatal CPF exposure had no significant effect on locomotor activity or on locomotor habituation, a form of non-associative memory assessed in open fields. Spatial navigation in the Morris water maze (MWM) was found to be sexually dimorphic among guinea pigs, with males outperforming females. Prenatal CPF exposure impaired spatial learning more significantly among male than female guinea pigs and, consequently, reduced the sexual dimorphism of the task. The results presented here, which strongly support the test hypothesis, reveal that the guinea pig is a valuable animal model for preclinical assessment of the developmental neurotoxicity of OP pesticides. These findings are far reaching as they lay the groundwork for future studies aimed at identifying therapeutic interventions to treat and/or prevent the neurotoxic effects of CPF in the developing brain. PMID:27296654

  12. Effect of organophosphorus insecticides and their metabolites on astroglial cell proliferation

    International Nuclear Information System (INIS)

    Guizzetti, Marina; Pathak, Shantha; Giordano, Gennaro; Costa, Lucio G.

    2005-01-01

    Though little attention has been given to the possibility that glial cells may represent a target for the developmental neurotoxicity of organophosphorus (OP) insecticides, recent evidence, obtained in particular with chlorpyrifos (CP), suggests that developmental exposure to this compound may indeed target astrocytes. To substantiate and expand these observations, we carried out a series of in vitro studies utilizing fetal rat astrocytes and a human astrocytoma cell line, 1321N1 cells, to investigate the effect of the OPs CP, diazinon (DZ) and parathion (P), their oxygen analogs chlorpyrifos oxon (CPO), diazoxon (DZO) and paraoxon (PO), and their metabolites 3,5,6-trichloro-2-pyridinol (TCP), 2-isopropyl-6-methyl-4-pyrimidol (IMP) and para-nitrophenol (PNP), on cell proliferation. In fetal rat astrocytes and astrocytoma cells maintained in serum, CP, DZ, P, CPO, DZO, and PO induced a concentration-dependent inhibition in [ 3 H]thymidine incorporation with a very similar potency (IC 50 between 45 and 57 μM). Among the other metabolites, PNP was the most potent (IC 50 = 70-80 μM), while TCP and IMP were much less effective (IC 50 > 100 μM). Cytotoxicity appears to account only for a small part of the effect on DNA synthesis. OP insecticides and their oxons were three- to six-fold more potent in inhibiting [ 3 H]thymidine incorporation when cells were synchronized in the G 0 /G 1 phase of the cell cycle and re-stimulated by carbachol or epidermal growth factor. These results suggest that OP insecticides and their oxons affect astroglial cell proliferation and that the transition from the G 0 /G 1 to the S/G 2 phase of the cell cycle may be particularly sensitive to the action of these compounds

  13. Hypothalamic Gene Transfer of BDNF Inhibits Breast Cancer Progression and Metastasis in Middle Age Obese Mice

    OpenAIRE

    Liu, Xianglan; McMurphy, Travis; Xiao, Run; Slater, Andrew; Huang, Wei; Cao, Lei

    2014-01-01

    Activation of the hypothalamus-adipocyte axis is associated with an antiobesity and anticancer phenotype in animal models of melanoma and colon cancer. Brain-derived neurotrophic factor (BDNF) is a key mediator in the hypothalamus leading to preferential sympathoneural activation of adipose tissue and the ensuing resistance to obesity and cancer. Here, we generated middle age obese mice by high fat diet feeding for a year and investigated the effects of hypothalamic gene transfer of BDNF on a...

  14. STUDY OF CLINICAL PROFILE AND OUTCOME OF ORGANOPHOSPHORUS POISONING IN RELATION TO PSEUDOCHOLINESTERASE LEVEL

    Directory of Open Access Journals (Sweden)

    Rajyalakshmi

    2017-11-01

    . CONCLUSION In the present study of 100 cases of pesticide poisoning, the following is the summary of our observations and conclusions. Pesticide poisoning is the most common in young adult males in the age group of 16-30 years i.e. 63%, mostly belonging to rural area. Oral route of exposure with suicidal intention accounts for 88% of cases. Accidental inhalational exposure accounts for 22 cases. Organophosphorus poisoning is the most common among the various pesticides available (82%. Chlorpyriphos was the most commonly used pesticide poison available. (35%, followed by Phorate (16% which accounted for most of the accidental inhalational poisoning. Organochlorines ranked second among the common pesticides used for poisoning (7%.

  15. The structural requirements of organophosphorus insecticides (OPI) for reducing chicken embryo NAD(+) content in OPI-induced teratogenesis in chickens.

    Science.gov (United States)

    Seifert, Josef

    2016-05-01

    The objective of this study was to determine the structural requirements of organophosphorus insecticides (OPI) for reducing chicken embryo nicotinamide adenine dinucleotide (NAD(+)) content in OPI-induced teratogenesis and compare them with those needed for OPI inhibition of yolk sac membrane kynurenine formamidase (KFase), the proposed primary target for OPI teratogens in chicken embryos. The comparative molecular field analysis (COMFA) of three-dimensional quantitative structure-activity relationship (3D QSAR) revealed the electrostatic and steric fields as good predictors of OPI structural requirements to reduce NAD(+) content in chicken embryos. The dominant electrostatic interactions were localized at nitrogen-1, nitrogen-3, nitrogen of 2-amino substituent of the pyrimidinyl of pyrimidinyl phosphorothioates, and at the oxygen of crotonamide carbonyl in crotonamide phosphates. Bulkiness of the substituents at carbon-6 of the pyrimidinyls and/or N-substituents of crotonamides was the steric structural component that contributed to superiority of those OPI for reducing embryonic NAD(+) levels. Both electrostatic and steric requirements are similar to those defined in our previous study for OPI inhibition of chicken embryo yolk sac membrane KFase. The findings of this study provide another piece of evidence for the cause-and-effect relationship between yolk sac membrane KFase inhibition and reduced embryo NAD(+) content in NAD-associated OPI-induced teratogenesis in chickens. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Age influences the effects of nicotine and monoamine oxidase inhibition on mood-related behaviors in rats.

    Science.gov (United States)

    Villégier, Anne-Sophie; Gallager, Brittney; Heston, Jon; Belluzzi, James D; Leslie, Frances M

    2010-03-01

    Epidemiological studies have demonstrated a comorbidity of smoking with depression and anxiety, particularly during adolescence. However, few animal studies have considered possible synergistic interactions between nicotine and other tobacco smoke constituents, such as monoamine oxidase (MAO) inhibitors, in the regulation of mood. The aim of the study was to test the hypothesis that nicotine combined with the irreversible MAO inhibitor, tranylcypromine, will differentially affect depression- and anxiety-related behaviors in adolescent and adult rats. Nicotine (0, 0.05, 0.2 mg/kg, s.c.) and tranylcypromine (3 mg/kg, i.p.) were tested separately, or together, on male rats aged postnatal days 30 and 68, in three mood-related behavioral tests: forced swim test (FST), elevated plus maze (EPM), and open field. Nicotine (0.2 mg/kg) in adults significantly decreased floating time in the FST and increased time spent in the open arm of the EPM, with no change in locomotor activity. Tranylcypromine pretreatment combined with nicotine (0.2 mg/kg) significantly increased locomotor activity and time spent in the center of the open field. Whereas nicotine alone had no significant effect on adolescents, it significantly increased locomotor activity and decreased floating time in the FST when combined with tranylcypromine pretreatment. There is an age-dependent effect of nicotine, alone and in combination with MAO inhibition, on mood-related behaviors. Whereas nicotine alone induces mood improvement in adults, it has no effect on adolescents. Nicotine combined with tranylcypromine has unique, age-dependent effects. Thus, experimental studies of smoking should consider both age and other tobacco constituents, such as MAO inhibitors, as critical factors.

  17. Systematic screen for mutants resistant to TORC1 inhibition in fission yeast reveals genes involved in cellular ageing and growth

    Directory of Open Access Journals (Sweden)

    Charalampos Rallis

    2014-01-01

    Target of rapamycin complex 1 (TORC1, which controls growth in response to nutrients, promotes ageing in multiple organisms. The fission yeast Schizosaccharomyces pombe emerges as a valuable genetic model system to study TORC1 function and cellular ageing. Here we exploited the combinatorial action of rapamycin and caffeine, which inhibit fission yeast growth in a TORC1-dependent manner. We screened a deletion library, comprising ∼84% of all non-essential fission yeast genes, for drug-resistant mutants. This screen identified 33 genes encoding functions such as transcription, kinases, mitochondrial respiration, biosynthesis, intra-cellular trafficking, and stress response. Among the corresponding mutants, 5 showed shortened and 21 showed increased maximal chronological lifespans; 15 of the latter mutants showed no further lifespan increase with rapamycin and might thus represent key targets downstream of TORC1. We pursued the long-lived sck2 mutant with additional functional analyses, revealing that the Sck2p kinase functions within the TORC1 network and is required for normal cell growth, global protein translation, and ribosomal S6 protein phosphorylation in a nutrient-dependent manner. Notably, slow cell growth was associated with all long-lived mutants while oxidative-stress resistance was not.

  18. Evaluation of medical countermeasures against organophosphorus compounds: the value of experimental data and computer simulations.

    Science.gov (United States)

    Worek, Franz; Aurbek, Nadine; Herkert, Nadja M; John, Harald; Eddleston, Michael; Eyer, Peter; Thiermann, Horst

    2010-09-06

    Despite extensive research for more than six decades on medical countermeasures against poisoning by organophosphorus compounds (OP) the treatment options are meagre. The presently established acetylcholinesterase (AChE) reactivators (oximes), e.g. obidoxime and pralidoxime, are insufficient against a number of nerve agents and there is ongoing debate on the benefit of oxime treatment in human OP pesticide poisoning. Up to now, the therapeutic efficacy of oximes was mostly evaluated in animal models but substantial species differences prevent direct extrapolation of animal data to humans. Hence, it was considered essential to establish relevant experimental in vitro models for the investigation of oximes as antidotes and to develop computer models for the simulation of oxime efficacy in different scenarios of OP poisoning. Kinetic studies on the various interactions between erythrocyte AChE from various species, structurally different OP and different oximes provided a basis for the initial assessment of the ability of oximes to reactivate inhibited AChE. In the present study, in vitro enzyme-kinetic and pharmacokinetic data from a minipig model of dimethoate poisoning and oxime treatment were used to calculate dynamic changes of AChE activities. It could be shown that there is a close agreement between calculated and in vivo AChE activities. Moreover, computer simulations provided insight into the potential and limitations of oxime treatment. In the end, such data may be a versatile tool for the ongoing discussion of the pros and cons of oxime treatment in human OP pesticide poisoning. Copyright (c) 2009 Elsevier Ireland Ltd. All rights reserved.

  19. Developmental neurotoxicity of the organophosphorus insecticide chlorpyrifos: from clinical findings to preclinical models and potential mechanisms.

    Science.gov (United States)

    Burke, Richard D; Todd, Spencer W; Lumsden, Eric; Mullins, Roger J; Mamczarz, Jacek; Fawcett, William P; Gullapalli, Rao P; Randall, William R; Pereira, Edna F R; Albuquerque, Edson X

    2017-08-01

    Organophosphorus (OP) insecticides are pest-control agents heavily used worldwide. Unfortunately, they are also well known for the toxic effects that they can trigger in humans. Clinical manifestations of an acute exposure of humans to OP insecticides include a well-defined cholinergic crisis that develops as a result of the irreversible inhibition of acetylcholinesterase (AChE), the enzyme that hydrolyzes the neurotransmitter acetylcholine (ACh). Prolonged exposures to levels of OP insecticides that are insufficient to trigger signs of acute intoxication, which are hereafter referred to as subacute exposures, have also been associated with neurological deficits. In particular, epidemiological studies have reported statistically significant correlations between prenatal subacute exposures to OP insecticides, including chlorpyrifos, and neurological deficits that range from cognitive impairments to tremors in childhood. The primary objectives of this article are: (i) to address the short- and long-term neurological issues that have been associated with acute and subacute exposures of humans to OP insecticides, especially early in life (ii) to discuss the translational relevance of animal models of developmental exposure to OP insecticides, and (iii) to review mechanisms that are likely to contribute to the developmental neurotoxicity of OP insecticides. Most of the discussion will be focused on chlorpyrifos, the top-selling OP insecticide in the United States and throughout the world. These points are critical for the identification and development of safe and effective interventions to counter and/or prevent the neurotoxic effects of these chemicals in the developing brain. This is an article for the special issue XVth International Symposium on Cholinergic Mechanisms. © 2017 International Society for Neurochemistry.

  20. Influence of age-related changes in nitric oxide synthase-expressing neurons in the rat supraoptic nucleus on inhibition of salivary secretion.

    Science.gov (United States)

    Tanaka, Takehiko; Tamada, Yoshitaka; Suwa, Fumihiko

    2008-02-01

    Age-related inhibition of salivary secretion has been demonstrated in rats, and the nitric oxide (NO) present in the supraoptic nucleus (SON) and the medial septal area has been reported to play an inhibitory role in the regulation of salivary secretion. In the present study, we investigated the age-related changes occurring in the NO synthase (NOS)-expressing neurons in the SON, which is related to the production of NO, and discussed the interrelation between the age-related changes in the NOS-expressing neurons and the age-related inhibition of salivary secretion. Nissl staining and reduced nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) histochemistry were performed for young adult and aged rats. Quantitative analysis was also performed using the Nissl-stained and NADPH-d-positive neurons. Although the numbers of the Nissl-stained neurons did not change, significant age-related increases were detected in cell number, cell size and reactive density of the NADPH-d-positive neurons. Therefore, the production of NO in the SON neurons increased with age. We concluded that the age-related increase in the NO in the SON might be a factor that contributes to the age-related inhibition of salivary secretion.

  1. COX2 inhibition during nephrogenic period induces ANG II hypertension and sex-dependent changes in renal function during aging.

    Science.gov (United States)

    Reverte, Virginia; Tapia, Antonio; Loria, Analia; Salazar, Francisco; Llinas, M Teresa; Salazar, F Javier

    2014-03-01

    This study was performed to test the hypothesis that ANG II contributes to the hypertension and renal functional alterations induced by a decrease of COX2 activity during the nephrogenic period. It was also examined whether renal functional reserve and renal response to volume overload and high sodium intake are reduced in 3-4- and 9-11-mo-old male and female rats treated with vehicle or a COX2 inhibitor during nephrogenic period (COX2np). Our data show that this COX2 inhibition induces an ANG II-dependent hypertension that is similar in male and female rats. Renal functional reserve is reduced in COX2np-treated rats since their renal response to an increase in plasma amino acids levels is abolished, and their renal ability to eliminate a sodium load is impaired (P renal excretory ability is similar in both sexes during aging but does not induce the development of a sodium-sensitive hypertension. However, the prolonged high-sodium intake at 9-11 mo of age leads to a greater proteinuria in male than in female (114 ± 12 μg/min vs. 72 ± 8 μg/min; P Renal hemodynamic sensitivity to acute increments in ANG II is unaltered in both sexes and at both ages in COX2np-treated rats. In summary, these results indicate that the reduction of COX2 activity during nephrogenic period programs for the development of an ANG II-dependent hypertension, reduces renal functional reserve to a similar extent in both sexes, and increases proteinuria in males but not in females when there is a prolonged increment in sodium intake.

  2. Inhibition of free radical scavenging enzymes affects mitochondrial membrane permeability transition during growth and aging of yeast cells.

    Science.gov (United States)

    Deryabina, Yulia; Isakova, Elena; Sekova, Varvara; Antipov, Alexey; Saris, Nils-Erik L

    2014-12-01

    In this study, we investigated the change in the antioxidant enzymes activity, cell respiration, reactive oxygen species (ROS), and impairment of membrane mitochondria permeability in the Endomyces magnusii yeasts during culture growth and aging. We showed that the transition into stationary phase is the key tool to understanding interaction of these processes. This growth stage is distinguished by two-fold increase in ROS production and respiration rate as compared to those in the logarithmic phase. It results in induction of alternative oxidase (AO) in the stationary phase, decline of the main antioxidant enzymes activities, ROS-production, and mitochondria membrane permeability. Significant increase in the share of mitochondrial isoform of superoxide dismutase (SOD2) occurred in the stationary phase from 51.8% (24 h of cultivation) to 68.6% (48 h of cultivation). Upon blocking the essential ROS-scavenging enzymes, SODs and catalases (CATs) some heterogeneity of cell population was observed: 80-90% of cells displayed evident signs of early apoptosis (such as disorientation of mitochondria cristae, mitochondrial fragmentation and deformation of nuclear chromatine). However, 10-20% of the population were definitely healthy. It allowed to draw the conclusion that a complete system of cell antioxidant protection underlies normal mitochondria functioning while the E. magnusii yeasts grow and age. Moreover, this system provides unimpaired cell physiology under oxidative stress during culture aging in the stationary phase. Failures in mitochondria functions due to inhibition of ROS-scavenging enzymes of CATs and SODs could lead to damage of the cells and some signs of early apoptosis.

  3. Clinical emergency treatment of 68 critical patients with severe organophosphorus poisoning and prognosis analysis after rescue.

    Science.gov (United States)

    Dong, Hui; Weng, Yi-Bing; Zhen, Gen-Shen; Li, Feng-Jie; Jin, Ai-Chun; Liu, Jie

    2017-06-01

    This study reports the clinical emergency treatment of 68 critical patients with severe organophosphorus poisoning, and analyzes the prognosis after rescue.The general data of 68 patients with severe organophosphorus poisoning treated in our hospital were retrospectively analyzed. These patients were divided into 2 groups: treatment group, and control group. Patients in the control group received routine emergency treatment, while patients in the treatment group additionally received hemoperfusion plus hemodialysis on the basis of routine emergency treatment. The curative effects in these 2 groups and the prognosis after rescue were compared.Compared with the control group, atropinization time, recovery time of cholinesterase activity, recovery time of consciousness, extubation time, and length of hospital stay were shorter (P poisoning rebound rate was significantly lower (P treatment group.Hemoperfusion and hemodialysis on the basis of routine emergency treatment for critical patients with organophosphorus poisoning can improve rescue outcomes and improve the prognosis of patients, which should be popularized.

  4. Organophosphorus reagents in actinide separations: Unique tools for production, cleanup and disposal

    International Nuclear Information System (INIS)

    Nash, K. L.

    2000-01-01

    Interactions of actinide ions with phosphate and organophosphorus reagents have figured prominently in nuclear science and technology, particularly in the hydrometallurgical processing of irradiated nuclear fuel. Actinide interactions with phosphorus-containing species impact all aspects from the stability of naturally occurring actinides in phosphate mineral phases through the application of the bismuth phosphate and PUREX processes for large-scale production of transuranic elements to the development of analytical separation and environment restoration processes based on new organophosphorus reagents. In this report, an overview of the unique role of organophosphorus compounds in actinide production, disposal, and environment restoration is presented. The broad utility of these reagents and their unique chemical properties is emphasized

  5. Structure–efficiency relationships of cyclodextrin scavengers in the hydrolytic degradation of organophosphorus compounds

    Directory of Open Access Journals (Sweden)

    Sophie Letort

    2017-03-01

    Full Text Available New derivatives of cyclodextrins were prepared in order to determine the relative importance of the structural key elements involved in the degradation of organophosphorus nerve agents. To avoid a competitive inclusion between the organophosphorus substrate and the iodosobenzoate group, responsible for its degradation, the latter group had to be covalently bound to the cyclodextrin scaffold. Although the presence of the α nucleophile iodosobenzoate was a determinant in the hydrolysis process, an imidazole group was added to get a synergistic effect towards the degradation of the agents. The degradation efficiency was found to be dependent on the relative position of the heterocycle towards the reactive group as well as on the nature of the organophosphorus derivative.

  6. A systems-level approach for investigating organophosphorus pesticide toxicity.

    Science.gov (United States)

    Zhu, Jingbo; Wang, Jing; Ding, Yan; Liu, Baoyue; Xiao, Wei

    2018-03-01

    The full understanding of the single and joint toxicity of a variety of organophosphorus (OP) pesticides is still unavailable, because of the extreme complex mechanism of action. This study established a systems-level approach based on systems toxicology to investigate OP pesticide toxicity by incorporating ADME/T properties, protein prediction, and network and pathway analysis. The results showed that most OP pesticides are highly toxic according to the ADME/T parameters, and can interact with significant receptor proteins to cooperatively lead to various diseases by the established OP pesticide -protein and protein-disease networks. Furthermore, the studies that multiple OP pesticides potentially act on the same receptor proteins and/or the functionally diverse proteins explained that multiple OP pesticides could mutually enhance toxicological synergy or additive on a molecular/systematic level. To the end, the integrated pathways revealed the mechanism of toxicity of the interaction of OP pesticides and elucidated the pathogenesis induced by OP pesticides. This study demonstrates a systems-level approach for investigating OP pesticide toxicity that can be further applied to risk assessments of various toxins, which is of significant interest to food security and environmental protection. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Plutonium and americium extraction studies with bifunctional organophosphorus extractants

    International Nuclear Information System (INIS)

    Navratil, J.D.

    1985-01-01

    Neutral bifunctional organophosphorus extractants, such as octylphenyl-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) and dihexyl-N,N-diethylcarbamoylmethylphosphonate (CMP), are under study at the Rocky Flats Plant (RFP) to remove plutonium and americium from the 7M nitric acid waste. These compounds extract trivalent actinides from strong nitric acid, a property which distinguishes them from monofunctional organiphosphorus reagents. Furthermore, the reagents extract hydroytic plutonium (IV) polymer which is present in the acid waste stream. The compounds extract trivalent actinides with a 3:1 stoichiometry, whereas tetra- and hexavalent actinides extract with a stoichiometry of 2:1. Preliminary studies indicate that the extracted plutonium polymer complex contains one to two molecules of CMP per plutonium ion and the plutonium(IV) maintains a polymeric structure. Recent studies by Horwitz and co-workers conclude that the CMPO and CMP reagents behave as monodentate ligands. At RFP, three techniques are being tested for using CMP and CMPO to remove plutonium and americium from nitric acid waste streams. The different techniques are liquid-liquid extraction, extraction chromatography, and solid-supported liquid membranes. Recent tests of the last two techniques will be briefly described. In all the experiments, CMP was an 84% pure material from Bray Oil Co. and CMPO was 98% pure from M and T Chemicals

  8. Preparation of Electrochemical Biosensor for Detection of Organophosphorus Pesticides

    Directory of Open Access Journals (Sweden)

    Ashish Gothwal

    2014-01-01

    Full Text Available Polyvinyl chloride (PVC can be used to develop reaction beaker which acts as electrochemical cell for the measurement of OP pesticides. Being chemically inert, corrosion resistant, and easy in molding to various shapes and size, PVC can be used for the immobilization of enzyme. Organophosphorus hydrolase was immobilized covalently onto the chemically activated inner surface of PVC beaker by using glutaraldehyde as a coupling agent. The carbon nanotubes paste working electrode was constructed for amperometric measurement at a potential of +0.8 V. The biosensor showed optimum response at pH 8.0 with incubation temperature of 40°C. Km and Imax for substrate (methyl parathion were 322.58 µM and 1.1 µA, respectively. Evaluation study showed a correlation of 0.985, which was in agreement with the standard method. The OPH biosensor lost 50% of its initial activity after its regular use for 25 times over a period of 50 days when stored in 0.1 M sodium phosphate buffer, pH 8.0 at 4°C. No interference was observed by interfering species.

  9. Nifedipine inhibits advanced glycation end products (AGEs) and their receptor (RAGE) interaction-mediated proximal tubular cell injury via peroxisome proliferator-activated receptor-gamma activation

    International Nuclear Information System (INIS)

    Matsui, Takanori; Yamagishi, Sho-ichi; Takeuchi, Masayoshi; Ueda, Seiji; Fukami, Kei; Okuda, Seiya

    2010-01-01

    Research highlights: → Nifedipine inhibited the AGE-induced up-regulation of RAGE mRNA levels in tubular cells, which was prevented by GW9662, an inhibitor of peroxisome proliferator-activated receptor-γ. → GW9662 treatment alone increased RAGE mRNA levels in tubular cells. → Nifedipine inhibited the AGE-induced reactive oxygen species generation, NF-κB activation and increases in intercellular adhesion molecule-1 and transforming growth factor-β gene expression in tubular cells, all of which were blocked by GW9662. -- Abstract: There is a growing body of evidence that advanced glycation end products (AGEs) and their receptor (RAGE) interaction evokes oxidative stress generation and subsequently elicits inflammatory and fibrogenic reactions, thereby contributing to the development and progression of diabetic nephropathy. We have previously found that nifedipine, a calcium-channel blocker (CCB), inhibits the AGE-induced mesangial cell damage in vitro. However, effects of nifedipine on proximal tubular cell injury remain unknown. We examined here whether and how nifedipine blocked the AGE-induced tubular cell damage. Nifedipine, but not amlodipine, a control CCB, inhibited the AGE-induced up-regulation of RAGE mRNA levels in tubular cells, which was prevented by the simultaneous treatment of GW9662, an inhibitor of peroxisome proliferator-activated receptor-γ (PPARγ). GW9662 treatment alone was found to increase RAGE mRNA levels in tubular cells. Further, nifedipine inhibited the AGE-induced reactive oxygen species generation, NF-κB activation and increases in intercellular adhesion molecule-1 and transforming growth factor-beta gene expression in tubular cells, all of which were blocked by GW9662. Our present study provides a unique beneficial aspect of nifedipine on diabetic nephropathy; it could work as an anti-oxidative and anti-inflammatory agent against AGEs in tubular cells by suppressing RAGE expression via PPARγ activation.

  10. Nifedipine inhibits advanced glycation end products (AGEs) and their receptor (RAGE) interaction-mediated proximal tubular cell injury via peroxisome proliferator-activated receptor-gamma activation

    Energy Technology Data Exchange (ETDEWEB)

    Matsui, Takanori [Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume (Japan); Yamagishi, Sho-ichi, E-mail: shoichi@med.kurume-u.ac.jp [Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume (Japan); Takeuchi, Masayoshi [Department of Pathophysiological Science, Faculty of Pharmaceutical Science, Hokuriku University, Kanazawa (Japan); Ueda, Seiji; Fukami, Kei; Okuda, Seiya [Department of Medicine, Kurume University School of Medicine, Kurume (Japan)

    2010-07-23

    Research highlights: {yields} Nifedipine inhibited the AGE-induced up-regulation of RAGE mRNA levels in tubular cells, which was prevented by GW9662, an inhibitor of peroxisome proliferator-activated receptor-{gamma}. {yields} GW9662 treatment alone increased RAGE mRNA levels in tubular cells. {yields} Nifedipine inhibited the AGE-induced reactive oxygen species generation, NF-{kappa}B activation and increases in intercellular adhesion molecule-1 and transforming growth factor-{beta} gene expression in tubular cells, all of which were blocked by GW9662. -- Abstract: There is a growing body of evidence that advanced glycation end products (AGEs) and their receptor (RAGE) interaction evokes oxidative stress generation and subsequently elicits inflammatory and fibrogenic reactions, thereby contributing to the development and progression of diabetic nephropathy. We have previously found that nifedipine, a calcium-channel blocker (CCB), inhibits the AGE-induced mesangial cell damage in vitro. However, effects of nifedipine on proximal tubular cell injury remain unknown. We examined here whether and how nifedipine blocked the AGE-induced tubular cell damage. Nifedipine, but not amlodipine, a control CCB, inhibited the AGE-induced up-regulation of RAGE mRNA levels in tubular cells, which was prevented by the simultaneous treatment of GW9662, an inhibitor of peroxisome proliferator-activated receptor-{gamma} (PPAR{gamma}). GW9662 treatment alone was found to increase RAGE mRNA levels in tubular cells. Further, nifedipine inhibited the AGE-induced reactive oxygen species generation, NF-{kappa}B activation and increases in intercellular adhesion molecule-1 and transforming growth factor-beta gene expression in tubular cells, all of which were blocked by GW9662. Our present study provides a unique beneficial aspect of nifedipine on diabetic nephropathy; it could work as an anti-oxidative and anti-inflammatory agent against AGEs in tubular cells by suppressing RAGE expression

  11. Cytoplasmic vacuolation in cultured rat astrocytes induced by an organophosphorus agent requires extracellular signal-regulated kinase activation

    International Nuclear Information System (INIS)

    Isobe, Ichiro; Maeno, Yoshitaka; Nagao, Masataka; Iwasa, Mineo; Koyama, Hiroyoshi; Seko-Nakamura, Yoshimi; Monma-Ohtaki, Jun

    2003-01-01

    There are various toxic chemicals that cause cell death. However, in certain cases deleterious agents elicit various cellular responses prior to cell death. To determine the cellular mechanisms by which such cellular responses are induced is important, but sufficient attention has not been paid to this issue to date. In this study, we showed the characteristic effects of an organophosphorus (OP) agent, bis(pinacolyl methyl)phosphonate (BPMP), which we synthesized for the study of OP nerve agents, on cultured rat astrocytes. Morphologically, BPMP induced cytoplasmic vacuolation and stellation in the rat astrocytes. Cytoplasmic vacuolation is a cell pathological change observed, for example, in vacuolar degeneration, and stellation has been reported in astrocytic reactions against various stimuli. By pretreatment with cycloheximide, a protein synthesis inhibitor, stellation was inhibited, although vacuolation was not. Cell staining with a mitochondrion-selective dye indicated that the vacuolation probably occurs in the mitochondria that are swollen and vacuolatred in the center. Interestingly, the extracellular signal-regulated kinase (ERK) cascade inhibitor inhibited vacuolation and, to some extent, stellation. These results suggest that the ERK signaling cascade is important for the induction of mitochondrial vacuolation. We expect that a detailed study of these astrocytic reactions will provide us new perspectives regarding the variation and pathological significance of cell morphological changes, such as vacuolar degeneration, and also the mechanisms underlying various neurological disorders

  12. Poisoning of raptors with organophosphorus and carbamate pesticides with emphasis on Canada, U.S. and U.K.

    Science.gov (United States)

    Mineau, P.; Fletcher, M.R.; Glaser, L.C.; Thomas, N.J.; Brassard, C.; Wilson, L.K.; Elliott, J.E.; Lyon, L.A.; Henny, C.J.; Bollinger, T.; Porter, S.L.

    1999-01-01

    We reviewed cases of raptor mortality resulting from cholinesterase-inhibiting pesticides. We compiled records from the U.S., U.K. and Canada for the period 1985-95 (520 incidents) and surveyed the relevant literature to identify the main routes of exposure and those products that led to the greatest number of poisoning cases. A high proportion of cases in the U.K. resulted from abusive uses of pesticides (willful poisoning). The proportion was smaller in North America where problems with labeled uses of pesticides were as frequent as abuse cases. Poisoning resulting from labeled use was possible with a large number of granular pesticides and some seed treatments through secondary poisoning or through the ingestion of contaminated invertebrates, notably earthworms. With the more toxic products, residue levels in freshly-sprayed insects were high enough to cause mortality. The use of organophosphorus products as avicides and for the topical treatment of livestock appeared to be common routes of intoxication. The use of insecticides in dormant oils also gave rise to exposure that can be lethal or which can debilitate birds and increase their vulnerability. A few pesticides of high toxicity were responsible for the bulk of poisoning cases. Based on limited information, raptors appeared to be more sensitive than other bird species to organophosphorus and carbamate pesticides. Some of the more significant risk factors that resulted in raptor poisonings were: insectivory and vermivory; opportunistic taking of debilitated prey; scavenging, especially if the gastrointestinal tracts are consumed; presence in agricultural areas; perceived status as pest species; and flocking or other gregarious behavior at some part of their life cycle. Lethal or sublethal poisoning should always be considered in the diagnosis of dead or debilitated raptors even when another diagnosis (e.g., electrocution, car or building strike) is apparent. Many cases of poisoning are not currently

  13. Transfection of the IHH gene into rabbit BMSCs in a simulated microgravity environment promotes chondrogenic differentiation and inhibits cartilage aging.

    Science.gov (United States)

    Liu, Peng-Cheng; Liu, Kuan; Liu, Jun-Feng; Xia, Kuo; Chen, Li-Yang; Wu, Xing

    2016-09-27

    The effect of overexpressing the Indian hedgehog (IHH) gene on the chondrogenic differentiation of rabbit bone marrow-derived mesenchymal stem cells (BMSCs) was investigated in a simulated microgravity environment. An adenovirus plasmid encoding the rabbit IHH gene was constructed in vitro and transfected into rabbit BMSCs. Two large groups were used: conventional cell culture and induction model group and simulated microgravity environment group. Each large group was further divided into blank control group, GFP transfection group, and IHH transfection group. During differentiation induction, the expression levels of cartilage-related and cartilage hypertrophy-related genes and proteins in each group were determined. In the conventional model, the IHH transfection group expressed high levels of cartilage-related factors (Coll2 and ANCN) at the early stage of differentiation induction and expressed high levels of cartilage hypertrophy-related factors (Coll10, annexin 5, and ALP) at the late stage. Under the simulated microgravity environment, the IHH transfection group expressed high levels of cartilage-related factors and low levels of cartilage hypertrophy-related factors at all stages of differentiation induction. Under the simulated microgravity environment, transfection of the IHH gene into BMSCs effectively promoted the generation of cartilage and inhibited cartilage aging and osteogenesis. Therefore, this technique is suitable for cartilage tissue engineering.

  14. Organophosphorus flame retardants – Toxicity and influence on human health

    Directory of Open Access Journals (Sweden)

    Elżbieta Bruchajzer

    2015-06-01

    Full Text Available Organophosphorus flame retardants (flame retardants, FRs have been used for several decades in many industries, including the production of dyes, varnishes, adhesives, synthetic resins, polyvinyl chloride, hydraulic fluids, plastics and textiles. Their importance in recent times has increased due to i.a., significantly reduced use of polybrominated diphenyl ethers (PBDEs – persistent organic pollutants, dangerous for the environment. The aim of this study was to review the available literature data concerning phosphorous FRs primarily for neurotoxic, fertility, reproductive and carcinogenic effects. The analysis concerned the following most commonly used substances: tris(2-ethylhexylphosphate (TEHP, tris(2-butoxyethylphosphate (TBEP, triphenyl phosphate (TPP, tris(2-chloroethylphosphate (TCEP, tetrakis(hydroxymethyl-phosphonium chloride (THPC, tributyl phosphate (TBP, tricresyl phosphate (TCP, tris(2-chloroisopropylphosphate (TCPP, tris(1,3-dichloroisopropylphosphate (TDCP and tetrakis(hydroxymethyl phosphonium sulphate (THPS. In animal studies neurotoxic effects were found after exposure to TBEP, THPC, TBP and TCP, while in humans they were observed only after exposure to TCP. TCEP, THPS, TBP, TCP and TDCP caused disorders in fertility and/or fetal development of animals. Adverse effects on reproduction in humans may be caused by TPP, TCP, and TDCP. In laboratory animals the development of tumors was observed after high doses of TEHP, TCEP, TBP and TDCP. None of these compounds is classified as a human carcinogen. The environmental toxicity of phosphate FRs is low (except for TPP, TCEP and TBEP. They are not stable compounds, in living organisms they are metabolised and quickly excreted. Therefore, they can be used as an alternative to PBDEs. Med. Pr. 2015;66(2:235–264

  15. Degradation of organophosphorus compounds by X-ray irradiation

    International Nuclear Information System (INIS)

    Trebse, P.; Arcon, I.

    2002-01-01

    Complete text of publication follows. Our research presented in this contribution aims to elucidate the degradation mechanisms of organophosphate pesticides as organic pollutants by X-ray irradiation. Diazinon, one of the most widely used pesticides in Slovenia, has been chosen as a model compound for the study of radiation induced degradation of organophosphorus pesticides. Recent studies have shown that the degradation of the pesticide at normal conditions (room temperature, exposure to daylight) is strongly enhanced when the pesticide is exposed to UV light (Hg lamp, λ=254 nm, XeCl excimer laser, λ=308 nm). In our study we irradiated the pesticide in aqueous media with a white x-ray beam from a conventional x-ray source. Mo X-ray tube operating at the high voltage of 55 kV and a current of 45 mA was used. The flux of the continuous X-ray beam was stabilized within 1%. Saturated water solution of the pesticide (volume: 4mL, conc. of 40 mg L -1 ) was inserted in 1 cm long lucite cell with 1 mm thick lucite windows. The whole volume of the solution in the cell was exposed to the unfiltered X-ray beam. The dose rate on the sample was about 1 mGy/s. Different irradiation times between 30 min to 120 min were chosen to study the dependence of the pesticide decomposition with the absorbed dose. Solid phase extraction was employed for sample extraction from the solution, and gas chromatography was used for the identification and quantification of the compounds. The results show that the concentration of the pesticide in the solution decreases exponentially with the exposure time, i.e. with the absorbed dose. At irradiation conditions described above, the time constant of the exponential decrease was 74 min

  16. Coenzyme Q10 Inhibits the Aging of Mesenchymal Stem Cells Induced by D-Galactose through Akt/mTOR Signaling

    Directory of Open Access Journals (Sweden)

    Dayong Zhang

    2015-01-01

    Full Text Available Increasing evidences indicate that reactive oxygen species are the main factor promoting stem cell aging. Recent studies have demonstrated that coenzyme Q10 (CoQ10 plays a positive role in organ and cellular aging. However, the potential for CoQ10 to protect stem cell aging has not been fully evaluated, and the mechanisms of cell senescence inhibited by CoQ10 are still poorly understood. Our previous study had indicated that D-galactose (D-gal can remarkably induce mesenchymal stem cell (MSC aging through promoting intracellular ROS generation. In this study, we showed that CoQ10 could significantly inhibit MSC aging induced by D-gal. Moreover, in the CoQ10 group, the expression of p-Akt and p-mTOR was clearly reduced compared with that in the D-gal group. However, after Akt activating by CA-Akt plasmid, the senescence-cell number in the CoQ10 group was significantly higher than that in the control group. These results indicated that CoQ10 could inhibit D-gal-induced MSC aging through the Akt/mTOR signaling.

  17. Inhibiting Effects of Achyranthes Bidentata Polysaccharide and Lycium Barbarum Polysaccharide on Nonenzyme Glycation in D-galactose Induced Mouse Aging Model

    Institute of Scientific and Technical Information of China (English)

    HONG-BIN DENG; DA-PENG CUI; JIAN-MING JIANG; YAN-CHUN FENG; NIAN-SHENG CAI; DIAN-DONG LI

    2003-01-01

    To investigate the inhibiting effects and mechanism of achyranthes bidentata polysaccharide (ABP) and lycium barbarum polysaccharide (LBP) on nonenzyme glycation in D-galactose induced mouse aging model. Methods Serum AGE levels were determined by AGE-ELISA, MTT method was used to determine lymphocyte proliferation, IL-2 activity was determined by a bioassay method. Spontaneous motor activity was used to detect mouse's neuromuscular movement, latency of step-through method was used to examine learning and memory abilities of mouse, colormetric assay was used to determine hydroxyproline concentration in mouse skin, pyrogallol autoxidation method was used to determine superoxide dismutase (SOD) activity of erythrocytes. Results Decreased levels of serum AGE, hydroxyproline concentration in mouse skin and spontaneous motor activity in D-galactose mouse aging model were detected after treated with ABP or LBP, while lymphocyte proliferation and IL-2 activity, learning and memory abilities,SOD activity of erythrocytes, were enhanced. Conclusions ABP and LBP could inhibit nonenzyme glycation in D-galactose induced mouse aging model in vivo and ABP has a better inhibiting effect than LBP.

  18. Dialkyl phosphate metabolites of organophosphorus in applicators of agricultural pesticides in Majes – Arequipa (Peru

    Directory of Open Access Journals (Sweden)

    Chung Arturo

    2006-12-01

    Full Text Available Abstract Background Organophosphorus (OPs pesticides are the most commonly used pesticides in Peruvian agriculture. The population at risk for OPs exposure includes formulators, applicators and farmers. Majes Valley is the most important agricultural center of the Southern region of Peru. The present study was aimed to determine the knowledge about using OPs, safety practice and urinary dialkylphosphate metabolites on OP applicators in the Majes Valley, Peru. Methods This study was based on a questionnaire which included socio-demographic characteristics, knowledge of safety practices to handling OPs, characteristics of pesticide application and use of protective measures to avoid pesticide contamination. Exposure was assessed by measuring six urinary OP metabolites (DMP, DMTP, DMDTP, DEP, DETP, and DEDTP by gas chromatography using a single flame photometric detector. The sample consisted of 31 men and 2 women aged 20 – 65 years old. Results 76% of applicators had at least one urinary dialkylphosphate metabolite above the limit of detection. The geometric mean (GM and the geometric standard deviation (GSD of DMP and DEP were 5.73 ug/g cr. (GSD 2.51, and 6.08 ug/g cr. (GSD 3.63, respectively. The percentage of applicators with detectable DMP, DMDTP, and DMTP in urine was 72.72%, 3.03%, and 15.15%, respectively, while the corresponding figures for DEP, DETP, and DEDTP were 48.48%, 36.36% and 15.15%, respectively. There was no significant association between the use of protection practices and the absence of urine OPs metabolites suggesting inadequate protection practices. Conclusion The pesticide applicators in Majes Valley have significant exposure to OP pesticides, probably due to inappropriate protective practices. Future work should evaluate possible health effects.

  19. Antioxidant Role of Pomegranates on Liver and Brain Tissues of Rats Exposed to an Organophosphorus Insecticide

    International Nuclear Information System (INIS)

    Abd Elmonem, H.A.

    2014-01-01

    Toxicities of organophosphorus insecticides cause oxidative damage on many organs such as the liver and brain due to generation of reactive oxygen species. Pomegranate is among the richest fruit in poly - phenols. The aim of this study was to compare between the antioxidant strength of pomegranate juice (PJ) and pomegranate molasses (PM) and their effects on alanine transferase (ALT), aspartate aminotransferase (AST), Alkaline phosphatase (ALP) and total protein (TP) in liver and levels of malondialdehyde (MAD), reduced glutathione (GSH) and nitric oxide (NO) in rat liver and brain tissues exposed to 1/10 LD 50 diazinon (DI). Six groups each of 6 male albino rats were used comprising control, DI, PJ, PM, PJ + DI and PM + DI for 15 days. The activities of ALT, AST, and TP concentration in liver have been increased due to treatment of rats with DI. These increases restored to normalcy when rats were supplemented with PJ or PM with DI. The results demonstrate that treatment with DI induced significant increase in MDA and NO concentrations and significant decrease in GSH levels of liver and brain tissues. The administration of PJ or PM along with DI significant decrease in MDA and NO levels and significant increase in GSH level compared to DI-group. The present study suggest that PJ or PM has a potential protective effect as it can elevate antioxidant defense system, lessens induced oxidative dam - ages and protect the brain and liver tissue against DI-induced toxicity. In addition, comaring PJ with PM it was noticed that PJ had higher antioxidant activity as evidenced by increased GSH content and decreased NO level in the liver by greater extend than PM.

  20. Dietary cumulative acute risk assessment of organophosphorus, carbamates and pyrethroids insecticides for the Brazilian population.

    NARCIS (Netherlands)

    Jardim, Andreia Nunes Oliveira; Brito, Alessandra Page; van Donkersgoed, Gerda; Boon, Polly E; Caldas, Eloisa Dutra

    Cumulative acute dietary risk assessments of organophosphorus (OPs), carbamates (CBs) and pyrethroids (PYs) were conducted for the Brazilian population. Residue data for 30786 samples of 30 foods were obtained from two national monitoring programs and one University laboratory, and consumption data

  1. Immobilization of Organophosphorus Acid Anhydrolase Mutant Y212F on Silica Nanospheres

    Science.gov (United States)

    2016-09-01

    wild type organophosphorus acid anhydrolase (OPAA) for activity on G-type chemical nerve agents and observed increased activity on the most- toxic ...eventual use in determining particle-binding efficiency and enzymatic activity ..................................................4 5. Fluoride assay...7 TABLES 1. Results of Fluoride Release Assay from DFP Testing of Y212F Enzyme, before and after Conjugation to

  2. Infrared Spectroscopic Observations on the Fate of Organophosphorus Compounds Exposed to Atmospheric Moisture. Part 3

    Science.gov (United States)

    2007-05-01

    FATE OF ORGANOPHOSPHORUS COMPOUNDS EXPOSED TO ATMOSPHERIC MOISTURE PART III. PHOSPHINES, PHOSPHITES , PHOSPHONITES, PHOSPHINITES, PHOSPHORIC ACIDS ...The investigation continues with Phosphines, Phosphites , Phosphonites, Phosphinites, Phosphoric Acids , Phosphonic Acids , Phosphinic Acids , Phosphine...infrared spectrum of di-(2-ethylhexyl) phosphoric acid as a liquid film between KBr windows is given in Figure 104. The band assignments are as follows

  3. Monoclonal antibody-based broad-specificity immunoassay for monitoring organophosphorus pesticides in environmental water samples

    Science.gov (United States)

    The extensive use of organophosphorus pesticides (OPs) in agriculture and domestic settings can result in widespread water contamination. The development of easy-to-use and rapid-screening immunoassay methods in a class-selective manner is a topic of considerable environmental interest. In this wo...

  4. Determination of organophosphorus acids by thermo-spray liquid chromatography-mass spectrometry

    NARCIS (Netherlands)

    Wils, E.R.J.; Hulst, A.G.

    1988-01-01

    The determination of thirteen organophosphorus acids, hydrolysis products of nerve agents and pesticides, by a combination of ion-pair liquid chromatography on a reversed-phase C18 column and thermospray mass spectrometry was investigated. Ammonium acetate and three tetraalkylammonium salts with

  5. RESEARCH OF HEAVY METALS, ORGANOCHLORINE AND ORGANOPHOSPHORUS PESTICIDES IN POWDERED INFANT FORMULA

    Directory of Open Access Journals (Sweden)

    M.C. Abete

    2009-02-01

    Full Text Available During the period between october 2007 and november 2008 were collected 60 samples of powdered infant formula. The analysis for the detection of heavy metals, organochlorine and organophosphorus pesticides show that the environmental situation is under control and powdered infant formula satisfies this health requisite.

  6. Tracing organophosphorus and brominated flame retardants and plasticizers in an estuarine food web

    NARCIS (Netherlands)

    Brandsma, S.H.; Leonards, P.E.G.; Leslie, H.A.; de Boer, J.

    2015-01-01

    Nine organophosphorus flame retardants (PFRs) were detected in a pelagic and benthic food web of the Western Scheldt estuary, The Netherlands. Concentrations of several PFRs were an order of magnitude higher than those of the brominated flame retardants (BFRs). However, the detection frequency of

  7. Pre- and post-treatment effect of physostigmine on soman-inhibited human erythrocyte and muscle acetylcholinesterase in vitro

    International Nuclear Information System (INIS)

    Herkert, N.M.; Schulz, S.; Wille, T.; Thiermann, H.; Hatz, R.A.; Worek, F.

    2011-01-01

    Standard treatment of organophosphorus (OP) poisoning includes administration of an antimuscarinic (e.g., atropine) and of an oxime-based reactivator. However, successful oxime treatment in soman poisoning is limited due to rapid aging of phosphylated acetylcholinesterase (AChE). Hence, the inability of standard treatment procedures to counteract the effects of soman poisoning resulted in the search for alternative strategies. Recently, results of an in vivo guinea pig study indicated a therapeutic effect of physostigmine given after soman. The present study was performed to investigate a possible pre- and post-treatment effect of physostigmine on soman-inhibited human AChE given at different time intervals before or after perfusion with soman by using a well-established dynamically working in vitro model for real-time analysis of erythrocyte and muscle AChE. The major findings were that prophylactic physostigmine prevented complete inhibition of AChE by soman and resulted in partial spontaneous recovery of the enzyme by decarbamylation. Physostigmine given as post-treatment resulted in a time-dependent reduction of the protection from soman inhibition and recovery of AChE. Hence, these date indicate that physostigmine given after soman does not protect AChE from irreversible inhibition by the OP and that the observed therapeutic effect of physostigmine in nerve agent poisoning in vivo is probably due to other factors.

  8. Consumption of fruits and vegetables and probabilistic assessment of the cumulative acute exposure to organophosphorus and carbamate pesticides of schoolchildren in Slovenia.

    Science.gov (United States)

    Blaznik, Urška; Yngve, Agneta; Eržen, Ivan; Hlastan Ribič, Cirila

    2016-02-01

    Adequate consumption of fruits and vegetables is a part of recommendations for a healthy diet. The aim of the present study was to assess acute cumulative dietary exposure to organophosphorus and carbamate pesticides via fruit and vegetable consumption by the population of schoolchildren aged 11-12 years and the level of risk for their health. Cumulative probabilistic risk assessment methodology with the index compound approach was applied. Slovenia, primary schools. Schoolchildren (n 1145) from thirty-one primary schools in Slovenia. Children were part of the PRO GREENS study 2009/10 which assessed 11-year-olds' consumption of fruit and vegetables in ten European countries. The cumulative acute exposure amounted to 8.3 (95% CI 7.7, 10.6) % of the acute reference dose (ARfD) for acephate as index compound (100 µg/kg body weight per d) at the 99.9th percentile for daily intake and to 4.5 (95% CI 3.5, 4.7) % of the ARfD at the 99.9th percentile for intakes during school time and at lunch. Apples, bananas, oranges and lettuce contributed most to the total acute pesticides intake. The estimations showed that acute dietary exposure to organophosphorus and carbamate pesticides is not a health concern for schoolchildren with the assessed dietary patterns of fruit and vegetable consumption.

  9. Acute effects of a sarin-like organophosphorus agent, bis(isopropyl methyl)phosphonate, on cardiovascular parameters in anaesthetized, artificially ventilated rats

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Yoshimasa [Department of Pharmacology, Graduate School of Medical Sciences, Nagoya City University, Nagoya (Japan); Itoh, Takeo, E-mail: titoh@med.nagoya-cu.ac.jp [Department of Pharmacology, Graduate School of Medical Sciences, Nagoya City University, Nagoya (Japan); Shiraishi, Hiroaki [Department of Forensic Medicine, Institute of Biomedical and Health Sciences, Hiroshima University, Hiroshima (Japan); Maeno, Yoshitaka [Department of Forensic Medical Science, Graduate School of Medical Sciences, Nagoya City University, Nagoya (Japan); Arima, Yosuke; Torikoshi, Aiko; Namera, Akira [Department of Forensic Medicine, Institute of Biomedical and Health Sciences, Hiroshima University, Hiroshima (Japan); Makita, Ryosuke [Department of Nursing, Faculty of Health Sciences, Hiroshima Cosmopolitan University, Hiroshima (Japan); Yoshizumi, Masao [Department of Cardiovascular Physiology and Medicine, Institute of Biomedical and Health Sciences, Hiroshima University, Hiroshima (Japan); Nagao, Masataka [Department of Forensic Medicine, Institute of Biomedical and Health Sciences, Hiroshima University, Hiroshima (Japan)

    2013-10-01

    The organophosphorus compound sarin irreversibly inhibits acetylcholinesterase. We examined the acute cardiovascular effects of a sarin-like organophosphorus agent, bis(isopropyl methyl)phosphonate (BIMP), in anaesthetized, artificially ventilated rats. Intravenous administration of BIMP (0.8 mg/kg; the LD50 value) induced a long-lasting increase in blood pressure and tended to increase heart rate. In rats pretreated with the non-selective muscarinic-receptor antagonist atropine, BIMP significantly increased both heart rate and blood pressure. In atropine-treated rats, hexamethonium (antagonist of ganglionic nicotinic receptors) greatly attenuated the BIMP-induced increase in blood pressure without changing the BIMP-induced increase in heart rate. In rats treated with atropine plus hexamethonium, intravenous phentolamine (non-selective α-adrenergic receptor antagonist) plus propranolol (non-selective β-adrenergic receptor antagonist) completely blocked the BIMP-induced increases in blood pressure and heart rate. In atropine-treated rats, the reversible acetylcholinesterase inhibitor neostigmine (1 mg/kg) induced a transient increase in blood pressure, but had no effect on heart rate. These results suggest that in anaesthetized rats, BIMP induces powerful stimulation of sympathetic as well as parasympathetic nerves and thereby modulates heart rate and blood pressure. They may also indicate that an action independent of acetylcholinesterase inhibition contributes to the acute cardiovascular responses induced by BIMP. - Highlights: • A sarin-like agent BIMP markedly increased blood pressure in anaesthetized rats. • Muscarinic receptor blockade enhanced the BIMP-induced increase in blood pressure. • Ganglionic nicotinic receptor blockade attenuated the BIMP-induced response. • Blockade of α- as well as β-receptors attenuated the BIMP-induced response.

  10. Acute effects of a sarin-like organophosphorus agent, bis(isopropyl methyl)phosphonate, on cardiovascular parameters in anaesthetized, artificially ventilated rats

    International Nuclear Information System (INIS)

    Watanabe, Yoshimasa; Itoh, Takeo; Shiraishi, Hiroaki; Maeno, Yoshitaka; Arima, Yosuke; Torikoshi, Aiko; Namera, Akira; Makita, Ryosuke; Yoshizumi, Masao; Nagao, Masataka

    2013-01-01

    The organophosphorus compound sarin irreversibly inhibits acetylcholinesterase. We examined the acute cardiovascular effects of a sarin-like organophosphorus agent, bis(isopropyl methyl)phosphonate (BIMP), in anaesthetized, artificially ventilated rats. Intravenous administration of BIMP (0.8 mg/kg; the LD50 value) induced a long-lasting increase in blood pressure and tended to increase heart rate. In rats pretreated with the non-selective muscarinic-receptor antagonist atropine, BIMP significantly increased both heart rate and blood pressure. In atropine-treated rats, hexamethonium (antagonist of ganglionic nicotinic receptors) greatly attenuated the BIMP-induced increase in blood pressure without changing the BIMP-induced increase in heart rate. In rats treated with atropine plus hexamethonium, intravenous phentolamine (non-selective α-adrenergic receptor antagonist) plus propranolol (non-selective β-adrenergic receptor antagonist) completely blocked the BIMP-induced increases in blood pressure and heart rate. In atropine-treated rats, the reversible acetylcholinesterase inhibitor neostigmine (1 mg/kg) induced a transient increase in blood pressure, but had no effect on heart rate. These results suggest that in anaesthetized rats, BIMP induces powerful stimulation of sympathetic as well as parasympathetic nerves and thereby modulates heart rate and blood pressure. They may also indicate that an action independent of acetylcholinesterase inhibition contributes to the acute cardiovascular responses induced by BIMP. - Highlights: • A sarin-like agent BIMP markedly increased blood pressure in anaesthetized rats. • Muscarinic receptor blockade enhanced the BIMP-induced increase in blood pressure. • Ganglionic nicotinic receptor blockade attenuated the BIMP-induced response. • Blockade of α- as well as β-receptors attenuated the BIMP-induced response

  11. Planarian cholinesterase: in vitro characterization of an evolutionarily ancient enzyme to study organophosphorus pesticide toxicity and reactivation.

    Science.gov (United States)

    Hagstrom, Danielle; Hirokawa, Hideto; Zhang, Limin; Radic, Zoran; Taylor, Palmer; Collins, Eva-Maria S

    2017-08-01

    The freshwater planarian Dugesia japonica has recently emerged as an animal model for developmental neurotoxicology and found to be sensitive to organophosphorus (OP) pesticides. While previous activity staining of D. japonica, which possess a discrete cholinergic nervous system, has shown acylthiocholine catalysis, it is unknown whether this is accomplished through an acetylcholinesterase (AChE), butyrylcholinesterase (BChE), or a hybrid esterase and how OP exposure affects esterase activity. Here, we show that the majority of D. japonica cholinesterase (DjChE) activity departs from conventional AChE and BChE classifications. Inhibition by classic protonable amine and quaternary reversible inhibitors (ethopropazine, donepezil, tacrine, edrophonium, BW284c51, propidium) shows that DjChE is far less sensitive to these inhibitors than human AChE, suggesting discrete differences in active center and peripheral site recognition and structures. Additionally, we find that different OPs (chlorpyrifos oxon, paraoxon, dichlorvos, diazinon oxon, malaoxon) and carbamylating agents (carbaryl, neostigmine, physostigmine, pyridostigmine) differentially inhibit DjChE activity in vitro. DjChE was most sensitive to diazinon oxon and neostigmine and least sensitive to malaoxon and carbaryl. Diazinon oxon-inhibited DjChE could be reactivated by the quaternary oxime, pralidoxime (2-PAM), and the zwitterionic oxime, RS194B, with RS194B being significantly more potent. Sodium fluoride (NaF) reactivates OP-DjChE faster than 2-PAM. As one of the most ancient true cholinesterases, DjChE provides insight into the evolution of a hybrid enzyme before the separation into distinct AChE and BChE enzymes found in higher vertebrates. The sensitivity of DjChE to OPs and capacity for reactivation validate the use of planarians for OP toxicology studies.

  12. Lysophosphatidylcholine hydrolases of human erythrocytes, lymphocytes, and brain: Sensitive targets of conserved specificity for organophosphorus delayed neurotoxicants

    International Nuclear Information System (INIS)

    Vose, Sarah C.; Holland, Nina T.; Eskenazi, Brenda; Casida, John E.

    2007-01-01

    Brain neuropathy target esterase (NTE), associated with organophosphorus (OP)-induced delayed neuropathy, has the same OP inhibitor sensitivity and specificity profiles assayed in the classical way (paraoxon-resistant, mipafox-sensitive hydrolysis of phenyl valerate) or with lysophosphatidylcholine (LysoPC) as the substrate. Extending our earlier observation with mice, we now examine human erythrocyte, lymphocyte, and brain LysoPC hydrolases as possible sensitive targets for OP delayed neurotoxicants and insecticides. Inhibitor profiling of human erythrocytes and lymphocytes gave the surprising result of essentially the same pattern as with brain. Human erythrocyte LysoPC hydrolases are highly sensitive to OP delayed neurotoxicants, with in vitro IC 50 values of 0.13-85 nM for longer alkyl analogs, and poorly sensitive to the current OP insecticides. In agricultural workers, erythrocyte LysoPC hydrolyzing activities are similar for newborn children and their mothers and do not vary with paraoxonase status but have high intersample variation that limits their use as a biomarker. Mouse erythrocyte LysoPC hydrolase activity is also of low sensitivity in vitro and in vivo to the OP insecticides whereas the delayed neurotoxicant ethyl n-octylphosphonyl fluoride inhibits activity in vivo at 1-3 mg/kg. Overall, inhibition of blood LysoPC hydrolases is as good as inhibition of brain NTE as a predictor of OP inducers of delayed neuropathy. NTE and lysophospholipases (LysoPLAs) both hydrolyze LysoPC, yet they are in distinct enzyme families with no sequence homology and very different catalytic sites. The relative contributions of NTE and LysoPLAs to LysoPC hydrolysis and clearance from erythrocytes, lymphocytes, and brain remain to be defined

  13. Integrated Lateral Flow Test Strip with Electrochemical Sensor for Quantification of Phosphorylated Cholinesterase: Biomarker of Exposure to Organophosphorus Agents

    Energy Technology Data Exchange (ETDEWEB)

    Du, Dan; Wang, Jun; Wang, Limin; Lu, Donglai; Lin, Yuehe

    2012-02-08

    An integrated lateral flow test strip with electrochemical sensor (LFTSES) device with rapid, selective and sensitive response for quantification of exposure to organophosphorus (OP) pesticides and nerve agents has been developed. The principle of this approach is based on parallel measurements of post-exposure and baseline acetylcholinesterase (AChE) enzyme activity, where reactivation of the phosphorylated AChE is exploited to enable measurement of total amount of AChE (including inhibited and active) which is used as a baseline for calculation of AChE inhibition. Quantitative measurement of phosphorylated adduct (OP-AChE) was realized by subtracting the active AChE from the total amount of AChE. The proposed LFTSES device integrates immunochromatographic test strip technology with electrochemical measurement using a disposable screen printed electrode which is located under the test zone. It shows linear response between AChE enzyme activity and enzyme concentration from 0.05 to 10 nM, with detection limit of 0.02 nM. Based on this reactivation approach, the LFTSES device has been successfully applied for in vitro red blood cells inhibition studies using chlorpyrifos oxon as a model OP agent. This approach not only eliminates the difficulty in screening of low-dose OP exposure because of individual variation of normal AChE values, but also avoids the problem in overlapping substrate specificity with cholinesterases and avoids potential interference from other electroactive species in biological samples. It is baseline free and thus provides a rapid, sensitive, selective and inexpensive tool for in-field and point-of-care assessment of exposures to OP pesticides and nerve agents.

  14. A novel fluorimetric sensing platform for highly sensitive detection of organophosphorus pesticides by using egg white-encapsulated gold nanoclusters.

    Science.gov (United States)

    Yan, Xu; Li, Hongxia; Hu, Tianyu; Su, Xingguang

    2017-05-15

    Assays for organophosphorus pesticides (OPs) with high sensitivity as well as on-site screening have been urgently required to protect ecosystem and prevent disease. Herein, a novel fluorimetric sensing platform was constructed for quantitative detection of OPs via tyrosinase (TYR) enzyme-controlled quenching of gold nanoclusters (AuNCs). One-step green synthetic approach was developed for the synthesis of AuNCs by using chicken egg white (CEW) as template and stabilizer. Initially, TYR can catalyze the oxidation of dopamine to dopaminechrome, which can efficiently quench the fluorescence intensity of AuNCs at 630nm based on dynamic quenching process. However, with the presence of OPs, the activity of TYR was inhibited, resulting in the fluorescence recovery of AuNCs. This proposed fluorescence platform was demonstrated to enable rapid detection for OPs (paraoxon as model) and to provide excellent sensitivity with a detection limit of 0.1ngmL -1 . Significantly, the fluorescence probe was used to prepare paper-based test strips for visual detection of OPs, which validated the excellent potential for real-time and on-site application. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Optical detection of organophosphorus compounds based on Mn-doped ZnSe d-dot enzymatic catalytic sensor.

    Science.gov (United States)

    Gao, Xue; Tang, Guangchao; Su, Xingguang

    2012-01-01

    In this paper, we report a sensitive and selective method for detection of organophosphorus compounds (OPs) based on Mn:ZnSe d-dots-enzyme-hydrogen peroxide (H(2)O(2)) fluorescence quenching system. Acetylcholine esterase (AChE) can hydrolyze acetylcholine (ACh) to choline. Subsequently, choline oxidase (ChOx) oxidizes choline to generate H(2)O(2). The enzyme-generated H(2)O(2) can quench the fluorescence of Mn:ZnSe d-dots. When paraoxon are introduced in solution, it can interact with the active centers of AChE and decrease the enzyme activity. This leads to the decrease of the H(2)O(2) production and then the fluorescence quenching rate of Mn:ZnSe d-dots. Experimental results showed that the enzyme inhibition percentage of Mn:ZnSe d-dots-ChOx-AChE-ACh system was proportional to the logarithm of paraoxon in the range 4.84×10(-11) to 4.84×10(-6) mol/L with the detection limit (S/N=3) of 1.31×10(-11) mol/L. The proposed biosensor has been employed for quick determination of paraoxon in tap water and milk samples with satisfactory reproducibility and accuracy. This nano-biosensor was proved to be sensitive, rapid, simple and tolerance of most interfering substances. Copyright © 2012 Elsevier B.V. All rights reserved.

  16. Field studies on health effects from the application of two organophosphorus insecticide formulations by hand-held ULV to cotton.

    Science.gov (United States)

    Kummer, R; van Sittert, N J

    1986-10-01

    Two field studies to assess the health implications for farmers applying two different formulations containing organophosphorus (OP) pesticides to cotton by hand-held ULV are described. The first study, carried out in the Ivory Coast, involved the application of an endrin/DDT/methylparathion (MEP) formulation in an aromatic hydrocarbon solvent. The second study took place in Indonesia with a 20% monocrotophos formulation in a mixture of a glycol and a glycol ether. Both studies were carried out under actual field conditions. The purpose of the studies was to get a good assessment of the health hazards of the particular formulation, used under the specific circumstances and agronomic requirements of the area of application and taking into account all local, climatic and cultural conditions that could be of possible influence. The results showed that in both studies skin exposures took place during application and especially during handling, filling and cleaning, and that inhalation of spray mist was negligible. Absorption was confirmed by the presence in urine of metabolites of endrin and methylparathion in the Ivory Coast study, and of dimethyl phosphate in the Indonesia study. No clinical signs or symptoms of intoxication were discovered in either study, nor were inhibitions of cholinesterase (ChE) activity of health significance established under the conditions of the studies. In addition, various practical aspects such as choice of apparatus, of formulation, the application procedures etc. are discussed.

  17. Simultaneous detection of dual biomarkers from humans exposed to organophosphorus pesticides by combination of immunochromatographic test strip and ellman assay.

    Science.gov (United States)

    Yang, Mingming; Zhao, Yuting; Wang, Limin; Paulsen, Michael; Simpson, Christopher D; Liu, Fengquan; Du, Dan; Lin, Yuehe

    2018-05-01

    A novel sandwich immunoassay based immunochromatographic test strip (ICTS) has been developed for simultaneously measuring both butyrylcholinesterase (BChE) activity and the total amount of BChE (including inhibited and active enzyme) from 70 μLpost-exposure human plasma sample. The principle of this method is based on the BChE monoclonal antibody (MAb) capable of acting as both capture antibody and detection antibody. The BChE MAb which was immobilized on the test line was able to recognize both organophosphorus BChE adducts (OP-BChE) and BChE and provided equal binding affinity, permitting detection of the total enzyme amount in post-exposure human plasma samples. The formed immunocomplexes on the test line can further be excised from the test-strip for subsequent off-line measurement of BChE activity using the Ellman assay. Therefore, dual biomarkers of BChE activity and phosphorylation (OP-BChE) will be obtained simultaneously. The whole sandwich-immunoassay was performed on one ICTS, greatly reducing analytical time. The ICTS sensor showed excellent linear responses for assaying total amount of BChE and active BChE ranging from 0.22 to 3.58nM and 0.22-7.17nM, respectively. Both the signal detection limits are 0.10nM. We validated the practical application of the proposed method to measure 124 human plasma samples from orchard workers and cotton farmers with long-term exposure to organophosphorus pesticides (OPs). The results were in highly agreement with LC/MS/MS which verified our method is extremely accurate. Combining the portability and rapidity of test strip and the compatibility of BChE MAb as both capture antibody and detection antibody, the developed method provides a baseline-free, low-cost and rapid tool for in-field monitoring of OP exposures. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. Short-term inhibition of 11β-hydroxysteroid dehydrogenase type 1 reversibly improves spatial memory but persistently impairs contextual fear memory in aged mice

    Science.gov (United States)

    Wheelan, Nicola; Webster, Scott P.; Kenyon, Christopher J.; Caughey, Sarah; Walker, Brian R.; Holmes, Megan C.; Seckl, Jonathan R.; Yau, Joyce L.W.

    2015-01-01

    High glucocorticoid levels induced by stress enhance the memory of fearful events and may contribute to the development of anxiety and posttraumatic stress disorder. In contrast, elevated glucocorticoids associated with ageing impair spatial memory. We have previously shown that pharmacological inhibition of the intracellular glucocorticoid-amplifying enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) improves spatial memory in aged mice. However, it is not known whether inhibition of 11β-HSD1 will have any beneficial effects on contextual fear memories in aged mice. Here, we examined the effects of UE2316, a selective 11β-HSD1 inhibitor which accesses the brain, on both spatial and contextual fear memories in aged mice using a vehicle-controlled crossover study design. Short-term UE2316 treatment improved spatial memory in aged mice, an effect which was reversed when UE2316 was substituted with vehicle. In contrast, contextual fear memory induced by foot-shock conditioning was significantly reduced by UE2316 in a non-reversible manner. When the order of treatment was reversed following extinction of the original fear memory, and a second foot-shock conditioning was given in a novel context, UE2316 treated aged mice (previously on vehicle) now showed increased fear memory compared to vehicle-treated aged mice (previously on UE2316). Renewal of the original extinguished fear memory triggered by exposure to a new environmental context may explain these effects. Thus 11β-HSD1 inhibition reverses spatial memory impairments with ageing while reducing the strength and persistence of new contextual fear memories. Potentially this could help prevent anxiety-related disorders in vulnerable elderly individuals. PMID:25497454

  19. Short-term inhibition of 11β-hydroxysteroid dehydrogenase type 1 reversibly improves spatial memory but persistently impairs contextual fear memory in aged mice.

    Science.gov (United States)

    Wheelan, Nicola; Webster, Scott P; Kenyon, Christopher J; Caughey, Sarah; Walker, Brian R; Holmes, Megan C; Seckl, Jonathan R; Yau, Joyce L W

    2015-04-01

    High glucocorticoid levels induced by stress enhance the memory of fearful events and may contribute to the development of anxiety and posttraumatic stress disorder. In contrast, elevated glucocorticoids associated with ageing impair spatial memory. We have previously shown that pharmacological inhibition of the intracellular glucocorticoid-amplifying enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) improves spatial memory in aged mice. However, it is not known whether inhibition of 11β-HSD1 will have any beneficial effects on contextual fear memories in aged mice. Here, we examined the effects of UE2316, a selective 11β-HSD1 inhibitor which accesses the brain, on both spatial and contextual fear memories in aged mice using a vehicle-controlled crossover study design. Short-term UE2316 treatment improved spatial memory in aged mice, an effect which was reversed when UE2316 was substituted with vehicle. In contrast, contextual fear memory induced by foot-shock conditioning was significantly reduced by UE2316 in a non-reversible manner. When the order of treatment was reversed following extinction of the original fear memory, and a second foot-shock conditioning was given in a novel context, UE2316 treated aged mice (previously on vehicle) now showed increased fear memory compared to vehicle-treated aged mice (previously on UE2316). Renewal of the original extinguished fear memory triggered by exposure to a new environmental context may explain these effects. Thus 11β-HSD1 inhibition reverses spatial memory impairments with ageing while reducing the strength and persistence of new contextual fear memories. Potentially this could help prevent anxiety-related disorders in vulnerable elderly individuals. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Growth-inhibiting effect of tumor necrosis factor on human umbilical vein endothelial cells is enhanced with advancing age in vitro

    International Nuclear Information System (INIS)

    Shimada, Y.; Kaji, K.; Ito, H.; Noda, K.; Matsuo, M.

    1990-01-01

    We have examined the effects of in vitro aging on the growth capacity of human umbilical vein endothelial cells (HUVECs) under the influence of tumor necrosis factor (TNF) with or without interferon-gamma (IFN-gamma). The growth and colony-forming abilities of control cells were impaired with advancing age in vitro, especially at later stages (more than 70-80% of life span completed). It was found that treatment with TNF inhibited growth and colony-forming efficiency at any in vitro age. The effects of TNF were shown to increase with increasing in vitro age, as reflected by a more pronounced increase in doubling times, a decrease in saturation density, and a reduction in colony-forming efficiency. However, the characteristics of TNF receptors, including the dissociation constant, and the number of TNF-binding sites per cell-surface area remained rather constant. The effect of TNF was augmented by IFN-gamma at a dose that alone affected growth and colony formation only slightly. The augmentation by IFN-gamma was also found to depend on in vitro age; the synergy with TNF in the deterioration of colony-forming ability was observed only in aged cells. These results suggest that the intrinsic responsiveness of HUVECs to growth-inhibiting factors, as well as to growth-stimulating factors, changes during aging in vitro

  1. [On necessity to modify biochemical methods for detecting organophosphorus componds in chemical weapons extinction objects (review of literature)].

    Science.gov (United States)

    Prokofieva, D S; Shmurak, V I; Sadovnikov, S V; Gontcharov, N V

    2015-01-01

    The article covers problems of biochemical methods assessing organophosphorus toxic compounds in objects of chemical weapons extinction. The authors present results of works developing new, more specific and selective biochemical methods.

  2. Comparison of the Developmental and Acute Neurotoxicity of a Library of Organophosphorus Pesticides Using a Vertebrate Behavioral Assay

    Science.gov (United States)

    The U.S. Environmental Protection Agency is evaluating methods to screen and prioritize organophosphorus pesticides for neurotoxicity using behavioral tests in an in vivo, vertebrate, medium-throughput model (zebrafish; Danio rerio). Our behavioral testing paradigm assesses the e...

  3. Salient measures of inhibition and switching are associated with frontal lobe gray matter volume in healthy middle-aged and older adults.

    Science.gov (United States)

    Adólfsdóttir, Steinunn; Haász, Judit; Wehling, Eike; Ystad, Martin; Lundervold, Arvid; Lundervold, Astri J

    2014-11-01

    To investigate brain-behavior relationships between morphometric brain measures and salient executive function (EF) measures of inhibition and switching. One hundred participants (49-80 years) performed the Color Word Interference Test from the Delis-Kaplan Executive Function System (D-KEFS). Salient measures of EF components of inhibition and switching, of which the effect of more fundamental skills were regressed out, were analyzed using linear models and a conditional inference trees analysis taking intercorrelations between predictor variables (brain volumes, age, gender, and education) into account. The conditional inference trees analysis demonstrated a primary role of the middle frontal gyrus (MFG) in explaining variations in the salient EF measure of switching and combined inhibition/switching. Age predicted measures of inhibition. The study highlights the importance of considering fundamental cognitive skills and the use of a statistical method taking possible complex relationships between predictor variables into account when interpreting standard EF test results. Further studies should include MRI measures representing neural networks that may relate to CWIT performance, and longitudinal studies are required to investigate any causal relationships. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  4. Selectivity improvement of positive photoionization ion mobility spectrometry for rapid detection of organophosphorus pesticides by switching dopant concentration.

    Science.gov (United States)

    Zhou, Qinghua; Li, Jia; Wang, Bin; Wang, Shuang; Li, Haiyang; Chen, Jinyuan

    2018-01-01

    Ion mobility spectrometry (IMS) opened a potential avenue for the rapid detection of organophosphorus pesticides (OPPs), though an improved selectivity of stand-alone IMS was still in high demand. In this study, a stand-alone positive photoionization ion mobility spectrometry (PP-IMS) apparatus was constructed for the rapid detection of OPPs with acetone as dopant. The photoionization of acetone molecules was induced by the ultraviolet irradiation to produce the reactant ions (Ac) 2 H + , which were employed to ionize the OPPs including fenthion, imidan, phosphamidon, dursban, dimethoate and isocarbophos via the proton transfer reaction. Due to the difference in proton affinity, the tested OPPs exhibited the different dopant-dependent manners. Based on this observation, the switching of dopant concentration was implemented to improve the selectivity of PP-IMS for OPPs detection. For instance, a mixture of fenthion, dursban and dimethoate was tested. By switching the concentration of doped acetone from 0.07 to 2.33 to 19.94mgL -1 , the ion peaks of fenthion and dursban were inhibited in succession, achieving the selective detection of dimethoate at last. In addition, another mixture of imidan and phosphamidon was initially detected by PP-IMS with a dose of 0.07mgL -1 acetone, indicating that their ion peaks were severely overlapped; when the concentration of doped acetone was switched to 19.94mgL -1 , the inhibition of imidan signals promised the accurate identification of phosphamidon in mixture. Finally, the PP-IMS in combination of switching dopant concentration was applied to detect the mixed fenthion, dursban and dimethoate in Chinese cabbage, demonstrating the applicability of proposed method to real samples. Copyright © 2017. Published by Elsevier B.V.

  5. Resistance to organophosphorus agent toxicity in transgenic mice expressing the G117H mutant of human butyrylcholinesterase

    International Nuclear Information System (INIS)

    Wang Yuxia; Ticu Boeck, Andreea; Duysen, Ellen G.; Van Keuren, Margaret; Saunders, Thomas L.; Lockridge, Oksana

    2004-01-01

    Organophosphorus toxicants (OP) include chemical nerve agents and pesticides. The goal of this work was to find out whether an animal could be made resistant to OP toxicity by genetic engineering. The human butyrylcholinesterase (BChE) mutant G117H was chosen for study because it has the unusual ability to hydrolyze OP as well as acetylcholine, and it is resistant to inhibition by OP. Human G117H BChE, under the control of the ROSA26 promoter, was expressed in all tissues of transgenic mice. A stable transgenic mouse line expressed 0.5 μg/ml of human G117H BChE in plasma as well as 2 μg/ml of wild-type mouse BChE. Intestine, kidneys, stomach, lungs, heart, spleen, liver, brain, and muscle expressed 0.6-0.15 μg/g of G117H BChE. Transgenic mice were normal in behavior and fertility. The LD50 dose of echothiophate for wild-type mice was 0.1 mg/kg sc. This dose caused severe cholinergic signs of toxicity and lethality in wild-type mice, but caused no deaths and only mild toxicity in transgenic animals. The mechanism of protection was investigated by measuring acetylcholinesterase (AChE) and BChE activity. It was found that AChE and endogenous BChE were inhibited to the same extent in echothiophate-treated wild type and transgenic mice. This led to the hypothesis that protection against echothiophate toxicity was not explained by hydrolysis of echothiophate. In conclusion, the transgenic G117H BChE mouse demonstrates the factors required to achieve protection from OP toxicity in a vertebrate animal

  6. Fluvastatin inhibits AGE-induced cell proliferation and migration via an ERK5-dependent Nrf2 pathway in vascular smooth muscle cells.

    Directory of Open Access Journals (Sweden)

    Ae-Rang Hwang

    Full Text Available Advanced glycation endproduct (AGE-induced vascular smooth muscle cell (VSMC proliferation and reactive oxygen species (ROS production are emerging as important mechanisms of diabetic vasculopathy, but little is known about the molecular mechanism responsible for the antioxidative effects of statins on AGEs. It has been reported that statins exert pleiotropic effects on the cardiovascular system due to decreases in AGE-induced cell proliferation, migration, and vascular inflammation. Thus, in the present study, the authors investigated the molecular mechanism by which statins decrease AGE-induced cell proliferation and VSMC migration. In cultured VSMCs, statins upregulated Nrf2-related antioxidant gene, NQO1 and HO-1, via an ERK5-dependent Nrf2 pathway. Inhibition of ERK5 by siRNA or BIX02189 (a specific ERK5 inhibitor reduced the statin-induced upregulations of Nrf2, NQO1, and HO-1. Furthermore, fluvastatin was found to significantly increase ARE promoter activity through ERK5 signaling, and to inhibit AGE-induced VSMC proliferation and migration as determined by MTT assay, cell counting, FACS analysis, a wound scratch assay, and a migration chamber assay. In addition, AGE-induced proliferation was diminished in the presence of Ad-CA-MEK5α encoding a constitutively active mutant form of MEK5α (an upstream kinase of ERK5, whereas depletion of Nrf2 restored statin-mediated reduction of AGE-induced cell proliferation. Moreover, fluvastatin suppressed the protein expressions of cyclin D1 and Cdk4, but induced p27, and blocked VSMC proliferation by regulating cell cycle. These results suggest statin-induced activation of an ERK5-dependent Nrf2 pathway reduces VSMC proliferation and migration induced by AGEs, and that the ERK5-Nrf2 signal module be viewed as a potential therapeutic target of vasculopathy in patients with diabetes and complications of the disease.

  7. Taurine Pretreatment Prevents Isoflurane-Induced Cognitive Impairment by Inhibiting ER Stress-Mediated Activation of Apoptosis Pathways in the Hippocampus in Aged Rats.

    Science.gov (United States)

    Zhang, Yanan; Li, Dongliang; Li, Haiou; Hou, Dailiang; Hou, Jingdong

    2016-10-01

    Isoflurane, a commonly used inhalation anesthetic, may induce neurocognitive deficits, especially in elderly patients after surgery. Recent study demonstrated that isoflurane caused endoplasmic reticulum (ER) stress and subsequent neuronal apoptosis in the brain, contributing to cognitive deficits. Taurine, a major intracellular free amino acid, has been shown to inhibit ER stress and neuronal apoptosis in several neurological disorders. Here, we examined whether taurine can prevent isoflurane-induced ER stress and cognitive impairment in aged rats. Thirty minutes prior to a 4-h 1.3 % isoflurane exposure, aged rats were treated with vehicle or taurine at low, middle and high doses. Aged rats without any treatment served as control. The brains were harvested 6 h after isoflurane exposure for molecular measurements, and behavioral study was performed 2 weeks later. Compared with control, isoflurane increased expression of hippocampal ER stress biomarkers including glucose-regulated protein 78, phosphorylated (P-) inositol-requiring enzyme 1, P-eukaryotic initiation factor 2-α (EIF2α), activating transcription factor 4 (ATF-4), cleaved ATF-6 and C/EBP homologous protein, along with activation of apoptosis pathways as indicated by decreased B cell lymphoma 2 (BCL-2)/BCL2-associated X protein, increased expressions of cytochrome-c and cleaved caspase-3. Taurine pretreatment dose-dependently inhibited isoflurane-induced increase in expression of ER stress biomarkers except for P-EIF2α and ATF-4, and reversed isoflurane-induced changes in apoptosis-related proteins. Moreover, isoflurane caused spatial working memory deficits in aged rats, which were prevented by taurine pretreatment. The results indicate that taurine pretreatment prevents anesthetic isoflurane-induced cognitive impairment by inhibiting ER stress-mediated activation of apoptosis pathways in the hippocampus in aged rats.

  8. Comparative study on cleanup procedures for the determination of organophosphorus pesticides in vegetables

    International Nuclear Information System (INIS)

    Alvin, Chai Lian Kuet; Lau, Seng

    2008-01-01

    A study was carried out to compare the cleanup procedures for the determination of organophosphorus pesticides in vegetables. Eleven organophosphorus pesticides were extracted with acetone and methylene chloride. Extracts were cleanup by solid-phase extraction (SPE) mixed-mode column using quaternary amine and aminopropyl (SAX/ NH 2 ) or octadecyl (C 18 ) sorbents. The pesticides were determined by gas chromatography with flame photometric detector. The recovery results obtained from the SPE SAX/ NH 2 and C 18 cleanups in carrot, cucumber and green mustard samples were in the range of 71.0 % to 115 %. Lower recoveries were obtained for polar pesticides, methamidophos and dimethoate. These results were compared to the method currently used in the laboratory which does not include any cleanup. (author)

  9. Calcium uptake by sarcoplasmic reticulum in the presence of organophosphorus insecticide methyl-parathion

    International Nuclear Information System (INIS)

    Blasiak, J.

    1995-01-01

    Using an isotope labelling technique it has been shown that an organophosphorus insecticide methyl parathion (0,0-diethyl 0-4-nitrophenyl phosphorothionate) depressed calcium uptake by sarcoplasmic reticulum isolated from rabbit hind leg muscle. The effect was significant for insecticide concentrations of 50 and 100 μM and was dose-dependent. The insecticide exerted a more pronounced effect on calcium uptake in the presence of ATP in the reticulum environment than in the absence of ATP. The inhibitory action of methyl parathion on Ca 2+ accumulation by sarcoplasmic reticulum can cause a rise in myoplasmic free Ca 2+ , the essential prerequisite for contracture activation. Because methyl parathion, as well as other organophosphorus insecticides, is primarily neurotoxic, evidence of non-specific effect could be important for assessing its environmental safety. (author). 20 refs, 2 figs

  10. Effect of Intensive Atropine Doses (Rapid Incremental Loading and Titration for Management of Organophosphorus Pesticide Poisoning: a Case Series

    Directory of Open Access Journals (Sweden)

    Abu Saleh Ahmed

    2014-03-01

    Full Text Available Background:Acute poisoning with organophosphorus (OP pesticides is a common method of suicide and entails considerable mortality in Bangladesh. The objective of this study was to evaluate the effects and outcomes of a protocol for treatment of OP poisoning that included titrated incremental atropine as loading dose and slow infusion for maintenance.  Methods:In this prospective descriptive case series, definitive OP poisoned patients were enrolled in an adult medicine unit of Dhaka Medical College Hospital from April 2006 to April 2007. Clinical examinations were done as soon as the patient entered the ward. Patient’s demographics, comorbid conditions and the occurrence of specific clinical outcomes including death, need for assisted ventilation and clinical complications were recorded. The patients were treated according to the protocol. Results: A total of 56 patients were enrolled over the study period. The median age of the study population was 22.5 years. Most patients were men (67.8%. The most common clinical presentation was miosis (58.9%. In total, 11 patients died (19.6%. Intermediate syndrome developed in 12 patients (21.4% and 6 of them died. Assisted ventilation was required in 16 cases (28.5. Patients with diastolic blood pressure ≤ 70 mmHg and/or GCS ≤ 10 were significantly less likely to survive (P = 0.02, 0.006, respectively. Moreover, early respiratory failure (P < 0.001 and the need for assisted ventilation (P < 0.001 were significantly higher among deceased cases. The mortality rate in this study was similar to previous studies. The frequency of atropine toxicity in the present study (1.8% was considerably lower than conventional regimen used in previous studies. Conclusion:Using the new protocol, lower rate of atropine toxicity developed in victims. Hence, the new protocol appears to be safer and its effectiveness should be further evaluated in case control studies in Bangladesh.    How to cite this article: Ahmed AS

  11. Behaviorally activated mRNA expression profiles produce signatures of learning and enhanced inhibition in aged rats with preserved memory.

    Science.gov (United States)

    Haberman, Rebecca P; Colantuoni, Carlo; Koh, Ming Teng; Gallagher, Michela

    2013-01-01

    Aging is often associated with cognitive decline, but many elderly individuals maintain a high level of function throughout life. Here we studied outbred rats, which also exhibit individual differences across a spectrum of outcomes that includes both preserved and impaired spatial memory. Previous work in this model identified the CA3 subfield of the hippocampus as a region critically affected by age and integral to differing cognitive outcomes. Earlier microarray profiling revealed distinct gene expression profiles in the CA3 region, under basal conditions, for aged rats with intact memory and those with impairment. Because prominent age-related deficits within the CA3 occur during neural encoding of new information, here we used microarray analysis to gain a broad perspective of the aged CA3 transcriptome under activated conditions. Behaviorally-induced CA3 expression profiles differentiated aged rats with intact memory from those with impaired memory. In the activated profile, we observed substantial numbers of genes (greater than 1000) exhibiting increased expression in aged unimpaired rats relative to aged impaired, including many involved in synaptic plasticity and memory mechanisms. This unimpaired aged profile also overlapped significantly with a learning induced gene profile previously acquired in young adults. Alongside the increased transcripts common to both young learning and aged rats with preserved memory, many transcripts behaviorally-activated in the current study had previously been identified as repressed in the aged unimpaired phenotype in basal expression. A further distinct feature of the activated profile of aged rats with intact memory is the increased expression of an ensemble of genes involved in inhibitory synapse function, which could control the phenotype of neural hyperexcitability found in the CA3 region of aged impaired rats. These data support the conclusion that aged subjects with preserved memory recruit adaptive mechanisms to

  12. Organophosphorus acid anhydrolase from Alteromonas macleodii: structural study and functional relationship to prolidases

    Czech Academy of Sciences Publication Activity Database

    Štěpánková, Andrea; Dušková, Jarmila; Skálová, Tereza; Hašek, Jindřich; Koval, Tomáš; Ostergaard, L. H.; Dohnálek, Jan

    2013-01-01

    Roč. 69, č. 4 (2013), s. 346-354 ISSN 1744-3091 R&D Projects: GA ČR GA310/09/1407; GA ČR GA305/07/1073; GA MŠk EE2.3.30.0029 Institutional research plan: CEZ:AV0Z40500505 Institutional support: RVO:61389013 Keywords : organophosphorus acid anhydrolase * prolidases * bifunctional Subject RIV: CE - Biochemistry Impact factor: 0.568, year: 2013

  13. Inhibition of Mitochondrial Cytochrome c Release and Suppression of Caspases by Gamma-Tocotrienol Prevent Apoptosis and Delay Aging in Stress-Induced Premature Senescence of Skin Fibroblasts

    Directory of Open Access Journals (Sweden)

    Suzana Makpol

    2012-01-01

    Full Text Available In this study, we determined the molecular mechanism of γ-tocotrienol (GTT in preventing cellular aging by focusing on its anti-apoptotic effect in stress-induced premature senescence (SIPS model of human diploid fibroblasts (HDFs. Results obtained showed that SIPS exhibited senescent-phenotypic characteristic, increased expression of senescence-associated β-galactosidase (SA β-gal and promoted G0/G1 cell cycle arrest accompanied by shortening of telomere length with decreased telomerase activity. Both SIPS and senescent HDFs shared similar apoptotic changes such as increased Annexin V-FITC positive cells, increased cytochrome c release and increased activation of caspase-9 and caspase-3 (P<0.05. GTT treatment resulted in a significant reduction of Annexin V-FITC positive cells, inhibited cytochrome c release and decreased activation of caspase-9 and caspase-3 (P<0.05. Gene expression analysis showed that GTT treatment down regulated BAX mRNA, up-regulated BCL2A1 mRNA and decreased the ratio of Bax/Bcl-2 protein expression (P<0.05 in SIPS. These findings suggested that GTT inhibits apoptosis by modulating the upstream apoptosis cascade, causing the inhibition of cytochrome c release from the mitochondria with concomitant suppression of caspase-9 and caspase-3 activation. In conclusion, GTT delays cellular senescence of human diploid fibroblasts through the inhibition of intrinsic mitochondria-mediated pathway which involved the regulation of pro- and anti-apoptotic genes and proteins.

  14. Oxalomalate reduces expression and secretion of vascular endothelial growth factor in the retinal pigment epithelium and inhibits angiogenesis: Implications for age-related macular degeneration

    Directory of Open Access Journals (Sweden)

    Sung Hwan Kim

    2016-12-01

    Full Text Available Clinical and experimental observations indicate a critical role for vascular endothelial growth factor (VEGF, secreted by the retinal pigment epithelium (RPE, in pathological angiogenesis and the development of choroidal neovascularization (CNV in age-related macular degeneration (AMD. RPE-mediated VEGF expression, leading to angiogenesis, is a major signaling mechanism underlying ocular neovascular disease. Inhibiting this signaling pathway with a therapeutic molecule is a promising anti-angiogenic strategy to treat this disease with potentially fewer side effects. Oxalomalate (OMA is a competitive inhibitor of NADP+-dependent isocitrate dehydrogenase (IDH, which plays an important role in cellular signaling pathways regulated by reactive oxygen species (ROS. Here, we have investigated the inhibitory effect of OMA on the expression of VEGF, and the associated underlying mechanism of action, using in vitro and in vivo RPE cell models of AMD. We found that OMA reduced the expression and secretion of VEGF in RPE cells, and consequently inhibited CNV formation. This function of OMA was linked to its capacity to activate the pVHL-mediated HIF-1α degradation in these cells, partly via a ROS-dependent ATM signaling axis, through inhibition of IDH enzymes. These findings reveal a novel role for OMA in inhibiting RPE-derived VEGF expression and angiogenesis, and suggest unique therapeutic strategies for treating pathological angiogenesis and AMD development.

  15. Inhibition of xanthine oxidase reduces oxidative stress and improves skeletal muscle function in response to electrically stimulated isometric contractions in aged mice

    Science.gov (United States)

    Ryan, Michael J.; Jackson, Janna R.; Hao, Yanlei; Leonard, Stephen S.; Alway, Stephen E.

    2012-01-01

    Oxidative stress is a putative factor responsible for reducing function and increasing apoptotic signaling in skeletal muscle with aging. This study examined the contribution and functional significance of the xanthine oxidase enzyme as a potential source of oxidant production in aged skeletal muscle during repetitive in situ electrically stimulated isometric contractions. Xanthine oxidase activity was inhibited in young adult and aged mice via a subcutaneously placed time release (2.5 mg/day) allopurinol pellet, 7 days prior to the start of in situ electrically stimulated isometric contractions. Gastrocnemius muscles were electrically activated with 20 maximal contractions for three consecutive days. Xanthine oxidase activity was 65% greater in the gastrocnemius muscle of aged mice compared to young mice. Xanthine oxidase activity also increased after in situ electrically stimulated isometric contractions in muscles from both young (33%) and aged (28%) mice, relative to contralateral non-contracted muscles. Allopurinol attenuated the exercise-induced increase in oxidative stress, but it did not affect the elevated basal levels of oxidative stress that was associated with aging. In addition, inhibition of xanthine oxidase activity decreased caspase 3 activity, but it had no effect on other markers of mitochondrial associated apoptosis. Our results show that compared to control conditions, suppression of xanthine oxidase activity by allopurinol reduced xanthine oxidase activity, H2O2 levels, lipid peroxidation and caspase-3 activity, prevented the in situ electrically stimulated isometric contraction-induced loss of glutathione, prevented the increase of catalase and copper-zinc superoxide dismutase activities, and increased maximal isometric force in the plantar flexor muscles of aged mice after repetitive electrically evoked contractions. PMID:21530649

  16. Long Alkyl Chain Organophosphorus Coupling Agents for in Situ Surface Functionalization by Reactive Milling

    Directory of Open Access Journals (Sweden)

    Annika Betke

    2014-08-01

    Full Text Available Innovative synthetic approaches should be simple and environmentally friendly. Here, we present the surface modification of inorganic submicrometer particles with long alkyl chain organophosphorus coupling agents without the need of a solvent, which makes the technique environmentally friendly. In addition, it is of great benefit to realize two goals in one step: size reduction and, simultaneously, surface functionalization. A top-down approach for the synthesis of metal oxide particles with in situ surface functionalization is used to modify titania with long alkyl chain organophosphorus coupling agents. A high energy planetary ball mill was used to perform reactive milling using titania as inorganic pigment and long alkyl chain organophosphorus coupling agents like dodecyl and octadecyl phosphonic acid. The final products were characterized by IR, NMR and X-ray fluorescence spectroscopy, thermal and elemental analysis as well as by X-ray powder diffraction and scanning electron microscopy. The process entailed a tribochemical phase transformation from the starting material anatase to a high-pressure modification of titania and the thermodynamically more stable rutile depending on the process parameters. Furthermore, the particles show sizes between 100 nm and 300 nm and a degree of surface coverage up to 0.8 mmol phosphonate per gram.

  17. Development of square wave voltammetry method for the assessment of organophosphorus compound impact on the cholinesterase of Pheretima with 2,6-dichloroindophenol as a redox indicator.

    Science.gov (United States)

    Qiu, Jingxia; Chen, Jin; Ma, Qianqian; Miao, Yuqing

    2009-09-01

    A square wave voltammetry method was developed for the assessment of organophosphorus (OPs) compound impact on the cholinesterase of Pheretima with 2,6-dichloroindophenol (2,6-DCIP) as a redox indicator. The substrate of acetylthiocholine is hydrolysed by the cholinesterase (ChE) from soil animal pheretima, and the produced thiocholine reacts with the 2,6-DCIP to give obvious shift of electrochemical signal. The inhibition of ChE was assessed by measuring the enzyme activity before and after incubating with parathion-methyl. The reduction peak current of 2,6-DCIP decreases with the time of enzymatical reaction. The ChE loses almost 32.74% activity after 10 min incubation with 1ng mL(-1) paraoxon and 54.62% with 10 microg mL(-1) paraoxon, while the activity that corresponds to 100 microg mL(-1) paraoxon was nearly completely inhibited. This method can be employed to assess the inhibition of ChE and investigate OPs impact on environmental animals.

  18. Age-related grey matter volume correlates of response inhibition and shifting in Attention Deficit Hyperactivity Disorder

    NARCIS (Netherlands)

    McAlonan, G. M.; Cheung, V.; Chua, S. E.; Oosterlaan, J.; Hung, S.; Tang, C.; Lee, C.; Kwong, S.; Ho, T.; Cheung, C.; Suckling, J.; Leung, P. W. L.

    2009-01-01

    Background Children with attention-deficit hyperactivity disorder (ADHD) have difficulties with executive function and impulse control which may improve with age. Aims To map the brain correlates of executive function in ADHD and determine age-related changes in reaction times and brain volumes.

  19. Age

    Science.gov (United States)

    ... adults? How can you reduce anesthesia risks in older patients? Age Age may bring wisdom but it also brings ... Ask your physician to conduct a pre-surgery cognitive test — an assessment of your mental function. The physician can use the results as a ...

  20. A STUDY OF PREDICTING THE NEED FOR VENTILATOR SUPPORT AND OUTCOME IN ORGANOPHOSPHORUS POISONING

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    Kalinga Bommankatte Eranaik

    2017-04-01

    Full Text Available BACKGROUND Organophosphorus compound poisoning is the most common poisonings in India because of easy availability, often requiring ICU care and ventilator support. Clinical research has indicated that respiratory failure is the most important cause of death due to Organophosphorus poisoning. It results in respiratory muscle weakness, pulmonary oedema, respiratory depression, increased secretions and bronchospasm. These complications and death can be prevented with timely Institution of ventilator support. The aim of present study was to identify the factors and predicting the need for ventilator support and outcome. Aim of the Study- To predict the need for ventilator support and outcome in organophosphate poisoning. MATERIALS AND METHODS Seventy consecutive patients admitted with a history of organophosphorus poisoning at KIMS, Hubli were taken for study after considering the inclusion and exclusion criteria. Detailed history, confirmation of poisoning, examination and other than routine investigations serum pseudocholinesterase and arterial blood gas analysis was done. The severity of organophosphorus poisoning was graded as mild, moderate and severe based on the factors which influence the need for ventilator support. RESULTS This study was conducted in 70 patients, out of which 48 (68.6% were male patients and 22 (31.4% were female patients. Among them 37 (53% patients required ventilation and 33 (47% expired. Chlorpyrifos, Dichlorvos and Monocrotophos were most commonly consumed poisons. 74% patients who consumed these compounds required ventilator support and 73% patients expired. 100% of patients presented with pin point pupil, fasciculation score > 4, respiratory rate > 20, GCS score < 7 and severe grade of poisoning required ventilator support and pseudocholinesterase < 900 U/L, 70% of metabolic acidosis and atropine requirement more than 180 mg within 48 hours required ventilator support and associated with high mortality. CONCLUSION

  1. Recombinant tumor necrosis factor alpha inhibits growth of methylcholanthrene-induced sarcoma and enhances natural killer activity of tumor-infiltrating lymphocytes in aging rats

    International Nuclear Information System (INIS)

    Ziolkowska, Maria; Nowak Joanna, J.; Janiak, Marek; Ryzewska, Alicja

    1994-01-01

    The effect of recombinant human tumor necrosis factors alpha (rHuTNF-α) on the growth of immunogenic, methylcholanthrene-induced sarcoma (MC-Sa) and natural killer (NK) cell activity of tumor-infiltrating lymphocytes (TIL) in adult and aging rats was investigated. In both groups of animals the growth of transplantable MC-Sa was markedly and similarly inhibited by multiple intratumoral (i.t.) injections of rHuTF-α. This effect was accompanied by stimulation of NK activity of tumor-infiltrating lymphocytes in adult as well as in aging rats. Studies ''in vitro'' demonstrated additionally that rHuTNF-α was a potent stimulator of NK but not of ADCC (antibody-dependent cellular cytotoxicity) activity of spleen lymphocytes from healthy animals. Our results indicate that the antitumor effect of TNF-α is comparable in adult and in aging rats bearing immunogenic MC-Sa. The inhibition of MC-Sa growth may be attributed not only to the TNF-α-induced necrosis of the neoplastic tissue but also to the ''in vivo'' stimulatory effect of this cytokine upon the NK-type function of lymphocytes infiltrating the tumor mass. (author). 31 refs, 5 figs, 2 tabs

  2. Aging

    International Nuclear Information System (INIS)

    Sasaki, Hideo; Kodama, Kazunori; Yamada, Michiko

    1991-01-01

    The hypothesis that exposure to ionizing radiation accelerates the aging process has been actively investigated at ABCC-RERF since 1958, when longitudinal cohort studies of the Adult Health Study (AHS) and the Life Span Study (LSS) were initiated. In their 1975 overall review of aging studies related to the atomic bomb (A-bomb) survivors, Finch and Beebe concluded that while most studies had shown no correlation between aging and radiation exposure, they had not involved the large numbers of subjects required to provide strong evidence for or against the hypothesis. Extending LSS mortality data up to 1978 did not alter the earlier conclusion that any observed life-shortening was associated primarily with cancer induction rather than with any nonspecific cause. The results of aging studies conducted during the intervening 15 years using data from the same populations are reviewed in the present paper. Using clinical, epidemiological, and laboratory techniques, a broad spectrum of aging parameters have been studied, such as postmortem morphological changes, tests of functional capacity, physical tests and measurements, laboratory tests, tissue changes, and morbidity. With respect to the aging process, the overall results have not been consistent and are generally thought to show no relation to radiation exposure. Although some preliminary results suggest a possible radiation-induced increase in atherosclerotic diseases and acceleration of aging in the T-cell-related immune system, further study is necessary to confirm these findings. In the future, applying the latest gerontological study techniques to data collected from subjects exposed 45 years ago to A-bomb radiation at relatively young ages will present a new body of data relevant to the study of late radiation effects. (author) 103 refs

  3. [Inhibition and resource capacity during normal aging: a confrontation of the dorsal-ventral and frontal models in a modified version of negative priming].

    Science.gov (United States)

    Martin, S; Brouillet, D; Guerdoux, E; Tarrago, R

    2006-01-01

    Over the past decades, cognitive psychology contribution to our understanding of aging relies on two major perspectives, focusing on the selective impact of age on either cognitive multiple-systems or global factors of cognition: slowing, working memory and inhibition. In the latter, reduction in inhibitory control during aging (in its access, deletion or restraint functions) is associated with poorer performance on a variety of tasks referring to memory, comprehension or language [Hasher, Zacks and May (16)]. The attractiveness of inhibition as an explanatory factor results in part in the absence of negative priming during aging. Negative priming refers to the slow down of latencies when individuals have to respond to recently ignored informations, compared to unrelated informations. The dissociation, between a preserved location negative priming and an absence of identity negative priming during aging, supports the dorsal-ventral model of inhibition which suggests that spatial and identity inhibition are supported by different and independent visual pathways. An alternative model, directly at odds, is that inhibitory mechanisms are supported by the frontal lobe. In this perspective, inhibition is not a central process responsible for the control of working memory contents, but an automatic and local mechanism whose triggering depends on controlled attention. Therefore, working memory drives efficient inhibition by sustaining task instructions and appropriate responses throughout task execution. This hypothesis is consistent with Houghton and Tipper's (17) architecture of selective attention. According to the authors, the presence or absence of automatic inhibition is very closely linked to a Match/Mismatch field whose function is to compare the present stimulus to an internal self-generated internal template. When an information fails to match the subject's current goals, the match/mismatch field causes an automatic inhibitory imbalance which reduces the to

  4. Aging

    International Nuclear Information System (INIS)

    Finch, S.C.; Beebe, G.W.

    1975-01-01

    The hypothesis that ionizing radiation accelerates natural aging has been under investigation at the Atomic Bomb Casualty Commission since 1959. Postmortem observations of morphologic and chemical changes, tests of functional capacity, physical tests and measurements, clinical laboratory tests, tissue changes, morbidity, and mortality have all been examined by ABCC investigators interested in this hypothesis. These studies have been beset with conceptual difficulties centered on the definition and measurement of aging. An empirical approach early led to the calculation of an index of physiologic age as a linear combination of age-related tests of various organ systems. Most studies have been negative but have not involved the large numbers that might be required to provide strong evidence for or against the hypothesis. Mortality, however, has been examined on the basis of a large sample and over the period 1950-1972 had provided no support for the hypothesis of radiation-accelerated aging. Ionizing radiation dose, of course shorten human life, but its life-shortening effect appears to be the result of specific radiation-induced disease, especially neoplasms. The hypothesis is now much less attractive than it was 10-20 years ago but still has some value in stimulating research on aging. The experience of the A-bomb survivors provides an unusual opportunity for a definitive test of the hypothesis. (auth.)

  5. A Disposable Organophosphorus Pesticides Enzyme Biosensor Based on Magnetic Composite Nano-Particles Modified Screen Printed Carbon Electrode

    Directory of Open Access Journals (Sweden)

    Weigang Wen

    2010-01-01

    Full Text Available A disposable organophosphorus pesticides (OPs enzyme biosensor based on magnetic composite nanoparticle-modified screen printed carbon electrodes (SPCE has been developed. Firstly, an acetylcholinesterase (AChE-coated Fe3O4/Au (GMP magnetic nanoparticulate (GMP-AChE was synthesized. Then, GMP-AChE was absorbed on the surface of a SPCE modified by carbon nanotubes (CNTs/nano-ZrO2/prussian blue (PB/Nafion (Nf composite membrane by an external magnetic field. Thus, the biosensor (SPCE|CNTs/ZrO2/PB/Nf|GMP-AChE for OPs was fabricated. The surface of the biosensor was characterized by scanning electron micrography (SEM and X-ray fluorescence spectrometery (XRFS and its electrochemical properties were studied by cyclic voltammetry (CV and differential pulse voltammetry (DPV. The degree of inhibition (A% of the AChE by OPs was determined by measuring the reduction current of the PB generated by the AChE-catalyzed hydrolysis of acetylthiocholine (ATCh. In pH = 7.5 KNO3 solution, the A was related linearly to the concentration of dimethoate in the range from 1.0 × 10-3–10 ng•mL-1 with a detection limit of 5.6 × 10-4 ng•mL-1. The recovery rates in Chinese cabbage exhibited a range of 88%–105%. The results were consistent with the standard gas chromatography (GC method. Compared with other enzyme biosensors the proposed biosensor exhibited high sensitivity, good selectivity with disposable, low consumption of sample. In particular its surface can be easily renewed by removal of the magnet. The convenient, fast and sensitive voltammetric measurement opens new opportunities for OPs analysis.

  6. Polyacrylic acid-coated cerium oxide nanoparticles: An oxidase mimic applied for colorimetric assay to organophosphorus pesticides.

    Science.gov (United States)

    Zhang, Shi-Xiang; Xue, Shi-Fan; Deng, Jingjing; Zhang, Min; Shi, Guoyue; Zhou, Tianshu

    2016-11-15

    It is important and urgent to develop reliable and highly sensitive methods that can provide on-site and rapid detection of extensively used organophosphorus pesticides (OPs) for their neurotoxicity. In this study, we developed a novel colorimetric assay for the detection of OPs based on polyacrylic acid-coated cerium oxide nanoparticles (PAA-CeO2) as an oxidase mimic and OPs as inhibitors to suppress the activity of acetylcholinesterase (AChE). Firstly, highly dispersed PAA-CeO2 was prepared in aqueous solution, which could catalyze the oxidation of TMB to produce a color reaction from colorless to blue. And the enzyme of AChE was used to catalyze the substrate of acetylthiocholine (ATCh) to produce thiocholine (TCh). As a thiol-containing compound with reducibility, TCh can decrease the oxidation of TMB catalyzed by PAA-CeO2. Upon incubated with OPs, the enzymatic activity of AChE was inhibited to produce less TCh, resulting in more TMB catalytically oxidized by PAA-CeO2 to show an increasing blue color. The two representative OPs, dichlorvos and methyl-paraoxon, were tested using our proposed assay. The novel assay showed notable color change in a concentration-dependent manner, and as low as 8.62 ppb dichlorvos and 26.73 ppb methyl-paraoxon can be readily detected. Therefore, taking advantage of such oxidase-like activity of PAA-CeO2, our proposed colorimetric assay can potentially be a screening tool for the precise and rapid evaluation of the neurotoxicity of a wealth of OPs. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. The effect of small-molecule inhibition of MAPKAPK2 on cell ageing phenotypes of fibroblasts from human Werner syndrome

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    Davis Terence

    2013-01-01

    Full Text Available Abstract Fibroblasts derived from the progeroid Werner syndrome (WS show reduced replicative lifespan and a “stressed” morphology, both phenotypes being alleviated by using the p38 MAP kinase inhibitor SB203580. Because p38 is a major hub for the control of stress-signalling pathways we were interested in examining the possible role for downstream kinases in order to refine our understanding of the role of p38 signalling in regulation of WS cell growth. To this end we treated WS and normal fibroblasts with MK2 inhibitors to determine whether MK2 inhibition would affect either the growth or morphology of WS cells. The first inhibitor, 7,8-dihydroxy-2,4-diamino-3-cyanobenzopyranopyridine (inhibitor 2, resulted in inhibition of WS cell growth and had no effect on morphology, effects that occurred below the level needed to inhibit MK2 and thus suggestive of inhibitor toxicity. The second inhibitor, 2-(2-quinolin-3-ylpyridin-4-yl-1,5,6,7-tetrahydro-4H-pyrrolo-[3,2-c]pyridin-4-one (CMPD16, resulted in a significant extension of WS fibroblast replicative capacity compared to normal cells. In addition, CMPD16 reverted the WS cellular morphology to that seen in normal dermal fibroblasts. These data suggest that MK2 activity plays a substantial role in proliferation control in WS cells. CMPD16 was not as effective in cellular lifespan extension as SB203580, however, suggesting that, although MK2 is a downstream kinase involved in cell cycle arrest, other p38 targets may play a role. Alternatively, as CMPD16 is toxic to cell growth at levels just above those that extend lifespan, it is possible that the therapeutic window is too small. However, as CMPD16 does show significant effects in WS fibroblasts, this acts as proof-of-principle for the efforts to design and synthesise improved MK2 inhibitors. As MK2 is involved in inflammatory processes and inflammation plays a major role in WS phenotypes, these data suggest MK2 as a potential therapeutic target

  8. (R)-α-Lipoic acid inhibits fructose-induced myoglobin fructation and the formation of advanced glycation end products (AGEs) in vitro.

    Science.gov (United States)

    Ghelani, Hardik; Razmovski-Naumovski, Valentina; Pragada, Rajeswara Rao; Nammi, Srinivas

    2018-01-15

    Fructose-mediated protein glycation (fructation) has been linked to an increase in diabetic and cardiovascular complications due to over consumption of high-fructose containing diets in recent times. The objective of the present study is to evaluate the protective effect of (R)-α-lipoic acid (ALA) against fructose-induced myoglobin fructation and the formation of advanced glycation end products (AGEs) in vitro. The anti-glycation activity of ALA was determined using the formation of AGEs fluorescence intensity, iron released from the heme moiety of myoglobin and the level of fructosamine. The fructation-induced myoglobin oxidation was examined using the level of protein carbonyl content and thiol group estimation. The results showed that co-incubation of myoglobin (1 mg/mL), fructose (1 M) and ALA (1, 2 and 4 mM) significantly inhibited the formation of AGEs during the 30 day study period. ALA markedly decreased the levels of fructosamine, which is directly associated with the reduction of AGEs formation. Furthermore, ALA significantly reduced free iron release from myoglobin which is attributed to the protection of myoglobin from fructose-induced glycation. The results also demonstrated a significant protective effect of ALA on myoglobin oxidative damages, as seen from decreased protein carbonyl content and increased protein thiols. These findings provide new insights into the anti-glycation properties of ALA and emphasize that ALA supplementation is beneficial in the prevention of AGEs-mediated diabetic and cardiovascular complications.

  9. Exposure of nonbreeding migratory shorebirds to cholinesterase-inhibiting contaminants in the western hemisphere

    Science.gov (United States)

    Strum, K.M.; Hooper, M.J.; Johnson, K.A.; Lanctot, Richard B.; Zaccagnini, M.E.; Sandercock, B.K.

    2010-01-01

    Migratory shorebirds frequently forage and roost in agricultural habitats, where they may be exposed to cholinesterase-inhibiting pesticides. Exposure to organophosphorus and carbamate compounds, common anti-cholinesterases, can cause sublethal effects, even death. To evaluate exposure of migratory shorebirds to organophosphorus and carbamates, we sampled birds stopping over during migration in North America and wintering in South America. We compared plasma cholinesterase activities and body masses of individuals captured at sites with no known sources of organophosphorus or carbamates to those captured in agricultural areas where agrochemicals were recommended for control of crop pests. In South America, plasma acetylcholinesterase and butyrylcholinesterase activity in Buff-breasted Sandpipers was lower at agricultural sites than at reference sites, indicating exposure to organophosphorus and carbamates. Results of plasma cholinesterase reactivation assays and foot-wash analyses were inconclusive. A meta-analysis of six species revealed no widespread effect of agricultural chemicals on cholinesterase activity. however, four of six species were negative for acetylcholinesterase and one of six for butyrylcholinesterase, indicating negative effects of pesticides on cholinesterase activity in a subset of shorebirds. Exposure to cholinesterase inhibitors can decrease body mass, but comparisons between treatments and hemispheres suggest that agrochemicals did not affect migratory shorebirds' body mass. Our study, one of the first to estimate of shorebirds' exposure to cholinesterase-inhibiting pesticides, suggests that shorebirds are being exposed to cholinesterase- inhibiting pesticides at specific sites in the winter range but not at migratory stopover sites. future research should examine potential behavioral effects of exposure and identify other potential sitesand levels of exposure. ?? The Cooper Ornithological Society 2010.

  10. Probabilistic acute risk assessment of cumulative exposure to organophosphorus and carbamate pesticides from dietary vegetables and fruits in Shanghai populations.

    Science.gov (United States)

    Li, Fan; Yuan, Yaqun; Meng, Pai; Wu, Min; Li, Shuguang; Chen, Bo

    2017-05-01

    Organophosphorus pesticides (OPs) and carbamate pesticides (CPs) are among the most widely used pesticides in China, playing a major role in protecting agricultural commodities. In this study, we determined the cumulative acute exposure to OPs and CPs of Shanghai residents from vegetables and fruits (VFs). The food consumption data were obtained from the Shanghai Food Consumption Survey (SHFCS) of 2012-14 including a total of 1973 participants aged 2-90 years. The pesticide residue data were obtained from the Shanghai monitoring programme during 2008-11 with 34 organophosphates and 11 carbamates analysed in a total of 5335 samples of VFs. A probabilistic approach was performed as recommended by the EFSA, using the optimistic model with non-detects set as zero and with processing factors (PFs) being used and the pessimistic model with non-detects replaced by limit of detection (LOD) and without PFs. We used the relative potency factor (RPF) method to normalise the various pesticides to the index compound (IC) of methamidophos and chlorpyrifos separately. Only in the pessimistic model using methamidophos as the IC was there was small risk of exposure exceeding the ARfD (3 µg kg - 1 bw day - 1 ) in the populations of preschool children (0.029%), school-age children (0.022%) and adults (0.002%). There were no risk of exposure exceeding the ARfD of methamidophos in the optimistic model and of chlorpyrifos (100 µg kg - 1 bw day - 1 ) in both optimistic and pessimistic models in all three populations. Considering the Chinese habits of overwhelmingly eating processed food (vegetables being cooked, and fruits being washed or peeled), we conclude that little acute risk was found for the exposure to VF-sourced OPs and CPs in Shanghai.

  11. Levels and distribution of organophosphorus flame retardants and plasticizers in fishes from Manila Bay, the Philippines

    International Nuclear Information System (INIS)

    Kim, Joon-Woo; Isobe, Tomohiko; Chang, Kwang-Hyeon; Amano, Atsuko; Maneja, Rommel H.; Zamora, Peter B.; Siringan, Fernando P.; Tanabe, Shinsuke

    2011-01-01

    Organophosphorus compounds (OPCs) and stable isotope ratios (δ 13 C and δ 15 N) were determined in 58 fishes belonging to 20 species collected from Manila Bay, the Philippines. OPCs were detected in most of the samples and found up to μg/g lw (lipid weight) level, suggesting their ubiquitous presence in the coastal marine environment of the Philippines. Higher levels (>1000 ng/g lw) of total OPCs were determined in yellowstriped goatfish, silver sillago, tripletail wrasse and bumpnose trevally indicates either their active uptake from ambient water or lower metabolic capacity of these species. Levels of triphenyl phosphate (TPhP) in demersal species showed a positive correlation with δ 15 N, indicating that TPhP was adsorbed onto the particle, settled down to the bottom sediment and accumulated through the benthic food web rather than the pelagic. Estimated dietary intake of OPCs in Manila Bay fishes were four to five orders of magnitude lower than the proposed reference dose (RfD). - Highlights: → Organophosphorus compounds (OPCs) were determined in fish from Manila Bay. → OPCs were detected up to μg/g lw, suggesting ubiquitous environmental contamination. → Among the 9 targeted OPCs, TEHP and TEP were found as the predominant compounds. → Estimated dietary intake through fish consumption was 4-5 orders of magnitude lower than RfD. → This is the first report on OPCs pollution in marine environment of Southeast Asia. - Occurrence and bioaccumulation of organophosphorus compounds (OPCs) were determined in fishes from Manila Bay.

  12. Determination of Twenty Organophosphorus Pesticides in Wheat Samples from Different Regions of Iran

    Directory of Open Access Journals (Sweden)

    Attaollah Shakoori *

    2017-09-01

    Full Text Available Background: Organophosphorus pesticides are widely used in agriculture, homes, gardens, and veterinary practices. Extensive application of pesticides in agriculture often results in residues of these compounds being absorbed into the foods, including wheat. The aim of this study was to evaluate the residue levels of 20 organophosphorus pesticides in wheat samples collected from different regions of Iran. Methods: This research reports a rapid, specific and sensitive multiresidue method based on the Quick Easy Cheap Effective Rugged and Safe (QuEChERS sample preparation method and gas chromatography with mass spectrometric detection in the selected ion monitoring mode (GC–SIM–MS to evaluate 20 organophosphorus pesticides in wheat samples. Results: In the concentration range of 20-200 ng/g, the calibration curves for each analyte was linear with a determination coefficient (R2 of 0.993 to 0.999. The limits of detection (LODs and quantitation (LOQs were between 2.5-6.7 and 7.5-20 ng/g, respectively. The mean recoveries obtained for three fortification levels (25, 50 and 100 ng/g, five replicates each were 80-114% with a satisfactory precision (RSD<20%. 31.1% samples contained residues of one or more target compounds. Chlorpyrifos was the most common residue (17.8%, followed by pirimiphos-methyl (6.7%, diazinon (4.4%, chlorpyrifos-methyl (1.1% and malathion (1.1%. Conclusion: Among the detected pesticides, only diazinon and malathion are permitted pesticides for wheat production in Iran. However, their concentrations were below the maximum residue levels (MRLs established by the Iranian National Standard Organization (INSO.

  13. Nutritional Supplementation Inhibits the Increase in Serum Malondialdehyde in Patients with Wet Age-Related Macular Degeneration

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    Toshiyuki Matsuura

    2017-01-01

    Full Text Available Purpose. To compare serum levels of malondialdehyde (MDA in patients with wet age-related macular degeneration (wAMD, patients with dry AMD (dAMD, and patients without AMD and to evaluate the efficacy of nutritional supplementation for treating elevated serum MDA in patients with wAMD. Methods. MDA levels were measured in sera from 20 patients with wAMD, 20 with dAMD, and 24 without AMD. Patients with wAMD were randomized to receive or not receive nutritional supplementation (10 patients in each group, and MDA levels were measured after 3 months of treatment. Results. MDA levels in patients with wAMD were significantly greater compared with patients without AMD. In eyes with wAMD, there was a significant correlation between MDA levels and choroidal neovascularization lesion area. Serum MDA levels decreased in most patients that received supplementation and significantly increased in those who did not. Conclusion. Baseline serum MDA levels were elevated in patients with wAMD, and MDA levels were directly correlated with choroidal neovascularization lesion area. In addition, nutritional supplementation appeared to exert a protective effect against oxidative stress in patients with wAMD.

  14. Construction of genetically engineered bacteria that degrades organophosphorus pesticide residues and can be easily detected by the fluorescence.

    Science.gov (United States)

    Li, Qin; Wang, Pan; Chen, Rui; Li, Wei; Wu, Yi-Jun

    2014-01-01

    Organophosphorus compounds (OPs) are widely used in agriculture and industry and there is increased concern about their toxicological effects in the environment. Bioremediation can offer an efficient and cost-effective option for the removal of OPs. Herein, we describe the construction of a genetically engineered microorganism (GEM) that can degrade OPs and be directly detected and monitored in the environment using an enhanced green fluorescent protein (EGFP) fusion strategy. The coding regions of EGFP, a reporter protein that can fluoresce by itself, and organophosphorus hydrolase (OPH), which has a broad substrate specificity and is able to hydrolyse a number of organophosphorus pesticides, were cloned into the expression vector pET-28b. The fusion protein of EGFP-OPH was expressed in E. coli BL21 (DE3) and the protein expression reached the highest level at 11 h after isopropyl beta-D-thiogalactopyranoside induction. The fluorescence of the GEM was detected by fluorescence spectrophotometry and microscopy, and its ability to degrade OPs was determined by OPH activity assay. Those GEM that express the fusion protein (EGFP and OPH) exhibited strong fluorescence intensity and also potent hydrolase activity, which could be used to degrade organophosphorus pesticide residues in the environment and can also be directly monitored by fluorescence.

  15. AMPEROMETRIC THICK-FILM STRIP ELECTRODES FOR MONITORING ORGANOPHOSPHATE NERVE AGENTS BASED ON IMMOBILIZED ORGANOPHOSPHORUS HYDROLASE. (R823663)

    Science.gov (United States)

    An amperometric biosensor based on the immobilization of organophosphorus hydrolase(OPH) onto screen-printed carbon electrodes is shown useful for the rapid, sensitive, and low-costdetection of organophosphate (OP) nerve agents. The sensor relies upon the sensitive and ra...

  16. DEVELOPMENT OF A RISK ASSESSMENT MODEL FOR THE EFFECTS OF ORGANOPHOSPHORUS PESTICIDES ON INFECTIOUS DISEASE SUSCEPTIBILITY AND THE IMMUNE SYSTEM

    Science.gov (United States)

    There is increased concern about the sublethal effects of organophosphorus (OP) pesticides on human and animal health. This class of chemicals has been shown to affect the immune function of macrophages and lymphocytes. Malathion, an OP compound, is one of the most widely used ...

  17. Structural Analysis and Bioengineering of Thermostable Pyrococcus furiosus Prolidase for the Optimization of Organophosphorus Nerve Agent Detoxification

    Science.gov (United States)

    2012-04-26

    organophosphorus acid anhydrase from a halophilic bacterial isolate. J Bacteriol, 173, 1938-1943. Du, X., Tove, S., Kast -Hutcheson, K. & Grunden, A. M...1938-1943. Du, X., Tove, S., Kast -Hutcheson, K. & Grunden, A. M. 2005. Characterization of the dinuclear metal center of Pyrococcus furiosus

  18. Confirmed organophosphorus and carbamate pesticide poisonings in South African wildlife (2009–2014

    Directory of Open Access Journals (Sweden)

    Christo J. Botha

    2015-12-01

    Full Text Available During a six-year period (from January 2009 to December 2014, specimens collected from 344 cases of suspected organophosphorus and carbamate pesticide poisonings in wildlife, including birds, were submitted to the Toxicology Laboratory (ARC-OVI for analysis. A positive diagnosis was made in 135 (39% of these cases. The majority of cases were from birds, which included Cape vultures (Gyps coprotheres and African white-backed vultures (Gyps africanus and bateleur eagles (Terathopius ecaudatus. In one incident 49 vultures were killed when a farmer intentionally laced carcasses with carbofuran in an attempt to control jackal predation. There were 22 incidents of poisoning in helmeted guineafowl (Numida meleagris. On nine different occasions blue cranes (Anthropoides paradiseus were poisoned, in one incident 14 birds were reported to have been killed. Over the period of investigation, there were 20 cases of poisoning involving mammalian species, the majority being vervet monkeys (Chlorocebus pygerythrus. The carbamate pesticides were responsible for 57 incidents of poisoning. Aldicarb, carbofuran and methomyl were detected in 26, 18 and 12 cases respectively. The majority of organophosphorus pesticide poisonings were caused by diazinon (n = 19, monocrotophos (n = 13 and methamidophos (n = 10.

  19. In vivo tracing of organophosphorus pesticides in cabbage (Brassica parachinensis) and aloe (Barbadensis)

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, Junlang; Chen, Guosheng; Zhou, Hong; Xu, Jianqiao; Wang, Fuxin; Zhu, Fang, E-mail: ceszf@mail.sysu.edu.cn; Ouyang, Gangfeng, E-mail: cesoygf@mail.sysu.edu.cn

    2016-04-15

    In vivo solid-phase microextraction (SPME) sampling method coupled with gas chromatography–mass spectrometry (GC–MS) analysis was employed to trace the uptake and elimination of organophosphorus pesticides (OPPs) in two kinds of edible plants, cabbage (Brassica parachinensis) and aloe (Barbadensis). The metabolism of fenthion in aloe was also investigated by the liquid chromatography tandem mass spectrometry analysis (LC–MS/MS) to understand the fate of OPPs in living plants better. Transpiration stream concentration factor (TSCF) and depuration rate constants of the OPPs in living plants were obtained therein. The health risk of the OPPs treated aloe was estimated by the maximum residue limit (MRL) approach, and it revealed that the OPPs were rather safe for their fast degradable property. However, peak concentration of fenthion-sulfoxide was found to exceed the MRL and was higher than that of the parent fenthion, which indicated the potential risk of pesticide metabolites. This study highlighted the application of in vivo SPME for contaminant tracing in different living edible plants. The in vivo tracing method is very convenient and can provide more data to evaluate the risk of different pesticides, which are very important for the safety of agriculture production. - Highlights: • In vivo SPME was employed to sample organophosphorus pesticides in vegetables. • Uptake and elimination of OPPs were traced in cabbage and aloe. • In vivo tracing of fenthion demonstrated its metabolites could be rather dangerous. • The risks of OPPs were assessed based on the in vivo tracing data.

  20. Metagenomic Functional Potential Predicts Degradation Rates of a Model Organophosphorus Xenobiotic in Pesticide Contaminated Soils

    Directory of Open Access Journals (Sweden)

    Thomas C. Jeffries

    2018-02-01

    Full Text Available Chemical contamination of natural and agricultural habitats is an increasing global problem and a major threat to sustainability and human health. Organophosphorus (OP compounds are one major class of contaminant and can undergo microbial degradation, however, no studies have applied system-wide ecogenomic tools to investigate OP degradation or use metagenomics to understand the underlying mechanisms of biodegradation in situ and predict degradation potential. Thus, there is a lack of knowledge regarding the functional genes and genomic potential underpinning degradation and community responses to contamination. Here we address this knowledge gap by performing shotgun sequencing of community DNA from agricultural soils with a history of pesticide usage and profiling shifts in functional genes and microbial taxa abundance. Our results showed two distinct groups of soils defined by differing functional and taxonomic profiles. Degradation assays suggested that these groups corresponded to the organophosphorus degradation potential of soils, with the fastest degrading community being defined by increases in transport and nutrient cycling pathways and enzymes potentially involved in phosphorus metabolism. This was against a backdrop of taxonomic community shifts potentially related to contamination adaptation and reflecting the legacy of exposure. Overall our results highlight the value of using holistic system-wide metagenomic approaches as a tool to predict microbial degradation in the context of the ecology of contaminated habitats.

  1. Separating esterase targets of organophosphorus compounds in the brain by preparative chromatography.

    Science.gov (United States)

    Mangas, I; Vilanova, E; Benabent, M; Estévez, J

    2014-02-10

    Low level exposure to organophosphorus esters (OPs) may cause long-term neurological effects and affect specific cognition domains in experimental animals and humans. Action on known targets cannot explain most of these effects by. Soluble carboxylesterases (EC 3.1.1.1) of chicken brain have been kinetically discriminated using paraoxon, mipafox and phenylmethyl sulfonylfluoride as inhibitors and phenyl valerate as a substrate. Three different enzymatic components were discriminated and called Eα, Eβ and Eγ. In this work, a fractionation procedure with various steps was developed using protein native separation methods by preparative HPLC. Gel permeation chromatography followed by ion exchange chromatography allowed enriched fractions with different kinetic behaviors. The soluble chicken brain fraction was fractionated, while total esterase activity, proteins and enzymatic components Eα, Eβ and Eγ were monitored in each subfraction. After the analysis, 13 fractions were pooled and conserved. Preincubation of the soluble chicken brain fraction of with the organophosphorus mipafox gave rise to a major change in the ion exchange chromatography profile, but not in the molecular exchanged chromatography profile, which suggest that mipafox permanently modifies the ionic properties of numerous proteins. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  2. Organophosphorus and Organochlorine Pesticides Bioaccumulation by Eichhornia crassipes in Irrigation Canals in an Urban Agricultural System.

    Science.gov (United States)

    Mercado-Borrayo, B M; Cram Heydrich, Silke; Pérez, Irma Rosas; Hernández Quiroz, Manuel; De León Hill, Claudia Ponce

    2015-01-01

    A natural wetland in Mexico City Metropolitan Area is one of the main suppliers of crops and flowers, and in consequence its canals hold a high concentration of organochlorine (OC) and organophosphorus (OP) pesticides. There is also an extensive population of water hyacinth (Eichhornia crassipes), which is considered a plague; but literature suggests water hyacinth may be used as a phytoremediator. This study demonstrates bioaccumulation difference for the OC in vivo suggesting their bioaccumulation is ruled by their log K(ow), while all the OP showed bioaccumulation regardless of their log K(ow). The higher bioaccumulation factors (BAF) of the accumulated OC pesticides cannot be explained by their log K(ow), suggesting that the OC pesticides may also be transported passively into the plant. Translocation ratios showed that water hyacinth is an accumulating plant with phytoremediation potential for all organophosphorus pesticides studied and some organochlorine pesticides. An equation for free water surface wetlands with floating macrophytes, commonly used for the construction of water-cleaning wetlands, showed removal of the pesticides by the wetland with room for improvement with appropriate management.

  3. The analysis of common metabolites of organophosphorus pesticides in urine by gas chromatography/mass spectrometry

    International Nuclear Information System (INIS)

    Park, Seong Soo; Pyo, Hee Soo; Lee, Kang Jin; Park, Song Ja; Park, Taek Kyu

    1998-01-01

    Most organophosphorus pesticides may be metabolized to yield some common phosphates in human or in animals, and these metabolites may be used as the exposure biomarkers to pesticides. In this study, we developed the extraction method of four phosphate metabolites from the spiked human urine in high recovery by the solid phase extraction with a reverse-phase cartridge (cyclohexyl silica) followed by the elution with methanol. The extracted urinary metabolites were derivatized with hexamethyldisilazane/trimethyl-chlorosilane/pyridine (2:1:10, v/v/v) and identified by gas chromatography/mass spectrometry. Calibration curve obtained from each metabolite standard using by GC/MS/SIM has shown good linearity and detection limits of metabolites were the range of 0.05-0.1 μg/ml in urine. Phenthoate, one of the organophosphorus pesticides, was orally administrated to rats. Four metabolites were detected in the rat urine. The results of this study may be applied to development of exposure biomarkers for monitoring of environmental pollutants

  4. Organochlorine and organophosphorus pesticide residues in fodder and milk samples along Musi river belt, India

    Directory of Open Access Journals (Sweden)

    Korrapati Kotinagu

    2015-04-01

    Full Text Available Aim: The present study was conducted to find the organochlorine pesticide (OCP and organophosphorus pesticide (OPP residues in fodder and milk samples along Musi river belt, India. Materials and Methods: Fodder and milk samples collected from the six zones of Musi river belt, Hyderabad India were analyzed by gas chromatography with electron capture detector for OCP residues and pulsated flame photometric detector for the presence of OPP residues. Results: The gas chromatographic analysis of fodder samples of Zone 5 of Musi river showed the residues of dicofol at concentration of 0.07±0.0007 (0.071-0.077. Among organophosphorus compounds, dimetheoate was present in milk samples collected from Zone 6 at a level of 0.13±0.006 (0.111-0.167. The residues of OCPs, OPPs and cyclodies were below the detection limit in the remaining fodder and milk samples collected from Musi river belt in the present study. Conclusion: The results indicate that the pesticide residues in fodder and milk samples were well below the maximum residue level (MRL values, whereas dicofol in fodder and dimethoate in milk were slightly above the MRL values specified by EU and CODEX.

  5. Organochlorine and organophosphorus pesticide residues in fodder and milk samples along Musi river belt, India.

    Science.gov (United States)

    Kotinagu, Korrapati; Krishnaiah, Nelapati

    2015-04-01

    The present study was conducted to find the organochlorine pesticide (OCP) and organophosphorus pesticide (OPP) residues in fodder and milk samples along Musi river belt, India. Fodder and milk samples collected from the six zones of Musi river belt, Hyderabad India were analyzed by gas chromatography with electron capture detector for OCP residues and pulsated flame photometric detector for the presence of OPP residues. The gas chromatographic analysis of fodder samples of Zone 5 of Musi river showed the residues of dicofol at concentration of 0.07±0.0007 (0.071-0.077). Among organophosphorus compounds, dimetheoate was present in milk samples collected from Zone 6 at a level of 0.13±0.006 (0.111-0.167). The residues of OCPs, OPPs and cyclodies were below the detection limit in the remaining fodder and milk samples collected from Musi river belt in the present study. The results indicate that the pesticide residues in fodder and milk samples were well below the maximum residue level (MRL) values, whereas dicofol in fodder and dimethoate in milk were slightly above the MRL values specified by EU and CODEX.

  6. Intensification of Organophosphorus Hydrolase Synthesis by Using Substances with Gas-Transport Function

    Directory of Open Access Journals (Sweden)

    Olga Senko

    2017-12-01

    Full Text Available We have performed studies and comparative analysis of the biosynthesis characteristics of intracellular recombinant enzyme, such as hexahistidine-containing organophosphorus hydrolase (His6-OPH in Escherichia coli SG13009[pREP4] cells when various perfluorocarbon compounds (PFC were introduced into the medium for cell cultivation. The PFC were found to facilitate the biosynthesis of His6-OPH: increased levels of the total OPH-activity (up to 37% were measured upon introduction of 1,1,1,2,2,3,3,4,4,5,5,6,6,6-tetradecafluorohexane (PFH and 4,7,10,13,16,19,22,25,28,31-decaoxaperfluoro-5,8,11,14,17,18,21,24,27,30-decamethyl tetratriacontane (Polyether II into culture medium. We have demonstrated the possibility of effective and multiple (at least five-fold use of PFH for biosynthesis of intracellular recombinant protein His6-OPH, which catalyzes the hydrolysis of organophosphorus pesticides (OP, is widely used in agriculture and can be applied as new antidote for OP-detoxification in vivo. The multiple use of PFH was achieved through recycling of this substance: sediment of Escherichia coli SG13009[pREP4] cell biomass was collected at the end of each culture growing step and disintegrated with ultrasound, and obtained residue containing almost all of the initially introduced PFC was then added to the medium at the start of the following culture growing step.

  7. ACUTE EXOGENOUS INTOXICATIONS WITH ORGANOPHOSPHORUS PESTICIDES: DURATION OF THE HOSPITAL TREATMENT AND CLINICAL CRITERIA FOR PROGNOSIS

    Directory of Open Access Journals (Sweden)

    Petko Marinov

    2017-05-01

    Full Text Available Purpose: Several criteria have been suggested to estimate the intoxication severity, yet so far no system of clinical criteria has been developed to determine the duration of hospitalisation. The forecast is linked to the influence of the extended corrected QT interval and GCS (Glasgow Coma Scale on the frequency of the developing acute pulmonary insufficiency and lethality. The average duration of hospital treatment is also crucial. First of all, it is determined by the intoxication severity and lasts from 3 to 26 days. The aim of this study is to develop an individual forecast about the duration of hospitalisation for patients suffering from acute exogenous intoxication with organophosphorus pesticides (OPP. Materials/Methods: The subjects are 160 patients. We use statistical regression analysis to study the significance of 5 of the most typical clinical indicators of organophosphorus intoxication on the duration of hospitalisation: type of conscience, presence of spasms, pulmonary oedema, shock and multi-organ insufficiency syndrome (MOIS. To forecast the treatment length, we obtain simplified mathematical expressions in the form of score estimates. Results: The significance of the clinical indicators “MOIS”, “conscience” and “spasm” has been confirmed. A forecast matrix that gives the opportunity to forecast the personal duration of hospital treatment for each patient has been built.

  8. In vivo tracing of organophosphorus pesticides in cabbage (Brassica parachinensis) and aloe (Barbadensis)

    International Nuclear Information System (INIS)

    Qiu, Junlang; Chen, Guosheng; Zhou, Hong; Xu, Jianqiao; Wang, Fuxin; Zhu, Fang; Ouyang, Gangfeng

    2016-01-01

    In vivo solid-phase microextraction (SPME) sampling method coupled with gas chromatography–mass spectrometry (GC–MS) analysis was employed to trace the uptake and elimination of organophosphorus pesticides (OPPs) in two kinds of edible plants, cabbage (Brassica parachinensis) and aloe (Barbadensis). The metabolism of fenthion in aloe was also investigated by the liquid chromatography tandem mass spectrometry analysis (LC–MS/MS) to understand the fate of OPPs in living plants better. Transpiration stream concentration factor (TSCF) and depuration rate constants of the OPPs in living plants were obtained therein. The health risk of the OPPs treated aloe was estimated by the maximum residue limit (MRL) approach, and it revealed that the OPPs were rather safe for their fast degradable property. However, peak concentration of fenthion-sulfoxide was found to exceed the MRL and was higher than that of the parent fenthion, which indicated the potential risk of pesticide metabolites. This study highlighted the application of in vivo SPME for contaminant tracing in different living edible plants. The in vivo tracing method is very convenient and can provide more data to evaluate the risk of different pesticides, which are very important for the safety of agriculture production. - Highlights: • In vivo SPME was employed to sample organophosphorus pesticides in vegetables. • Uptake and elimination of OPPs were traced in cabbage and aloe. • In vivo tracing of fenthion demonstrated its metabolites could be rather dangerous. • The risks of OPPs were assessed based on the in vivo tracing data.

  9. Radiolytic investigations of solutions of organophosphorus compounds in cyclohexane and benzene

    International Nuclear Information System (INIS)

    Otrebski, W.

    1981-01-01

    Organphosphorus compounds are used in various branches of the chemical industry, but in many cases the reaction mechanisms are not well elucidated and less is known about the intermediates of organophosphines. In order to learn more about these rather complicated processes several organophosphorus compounds were used as model substrates in cyclohexane or benzene solution. The systems have been investigated applying the pulse radiolysis technique and steady-state irradiation methods. As representative solutes were chosen diphenylphosphinous chloride, diphenylmethylphosphine, and triphenylphosphine. By means of the pulse radiolysis it was possible to obtain spectroscopic and kinetic data for characterization of the various transients. The final radiolytic products have been analyzed following steady-state and multipulse radiolysis. Since some of the rate constants were not directly accessible by the applied kinetic method, they have been determined by simulation computation. Thereby the experimental data obtained by pulse radiolysis were used. Based on the kinetic, spectroscopic and computed data as well as on the identification of final products, it was possible to elucidate the reaction mechanism of the diphenylphosphinous chloride/cyclohexane system. As a main primary specie was identified the diphenylphoshorus radical. Its spectral and kinetic data have been determined. The reactions of diphenylmethylphosphine involve the same radical, but only to a lesser extent. The reactions of the primary radiolysis products with triphenylphosphine yield mainly adducts. The results represent a contribution in the field of reaction kinetics of organophosphorus compounds. (author)

  10. PARP Inhibition Prevents Ethanol-Induced Neuroinflammatory Signaling and Neurodegeneration in Rat Adult-Age Brain Slice Cultures

    Science.gov (United States)

    Tajuddin, Nuzhath; Kim, Hee-Yong

    2018-01-01

    Using rat adult-age hippocampal-entorhinal cortical (HEC) slice cultures, we examined the role of poly [ADP-ribose] polymerase (PARP) in binge ethanol’s brain inflammatory and neurodegenerative mechanisms. Activated by DNA strand breaks, PARP (principally PARP1 in the brain) promotes DNA repair via poly [ADP-ribose] (PAR) products, but PARP overactivation triggers regulated neuronal necrosis (e.g., parthanatos). Previously, we found that brain PARP1 levels were upregulated by neurotoxic ethanol binges in adult rats and HEC slices, and PARP inhibitor PJ34 abrogated slice neurodegeneration. Binged HEC slices also exhibited increased Ca+2-dependent phospholipase A2 (PLA2) isoenzymes (cPLA2 IVA and sPLA2 IIA) that mobilize proinflammatory ω6 arachidonic acid (ARA). We now find in 4-day–binged HEC slice cultures (100 mM ethanol) that PARP1 elevations after two overnight binges precede PAR, cPLA2, and sPLA2 enhancements by 1 day and high-mobility group box-1 (HMGB1), an ethanol-responsive alarmin that augments proinflammatory cytokines via toll-like receptor-4 (TLR4), by 2 days. After verifying that PJ34 effectively blocks PARP activity (↑PAR), we demonstrated that, like PJ34, three other PARP inhibitors—olaparib, veliparib, and 4-aminobenzamide—provided neuroprotection from ethanol. Importantly, PJ34 and olaparib also prevented ethanol’s amplification of the PLA2 isoenzymes, and two PLA2 inhibitors were neuroprotective—thus coupling PARP to PLA2, with PLA2 activity promoting neurodegeneration. Also, PJ34 and olaparib blocked ethanol-induced HMGB1 elevations, linking brain PARP induction to TLR4 activation. The results provide evidence in adult brains that induction of PARP1 may mediate dual neuroinflammatory pathways (PLA2→phospholipid→ARA and HMGB1→TLR4→proinflammatory cytokines) that are complicit in binge ethanol-induced neurodegeneration. PMID:29339456

  11. Inhibition of Oxidative Stress and Skin Aging-Related Enzymes by Prenylated Chalcones and Other Flavonoids from Helichrysum teretifolium.

    Science.gov (United States)

    Popoola, Olugbenga K; Marnewick, Jeanine L; Rautenbach, Fanie; Ameer, Farouk; Iwuoha, Emmanuel I; Hussein, Ahmed A

    2015-04-20

    Ten flavonoid-related structures viz. heliteretifolin (1), isoxanthohumol (2), 2',4',6'-trihydroxy-3'-prenylchalcone (3), isoglabranin (4), glabranin (5), 7-methoxy-isoglabranin (6), quercetin (7), 4'-methoxyquercetin (8), 4'-methoxykaempferol (9) and mosloflavone (10) were isolated from a H. teretifolium methanolic extract and identified. One of them (compound 1) is reported for the first time from a natural source, while compounds 6, 8-10 were isolated for the first time from the genus Helichrysum. The total extract of H. teretifolium showed potent antioxidant activity. When tested for total antioxidant capacity compound 3 possesses moderate biological activity compared to 2, which displayed some of the highest TEAC values (4529.01 ± 2.44; 4170.66 ± 6.72) µM TE/g, respectively. Compounds 7 and 8 demonstrated the highest inhibitory activities on Fe2+-induced lipid peroxidation (IC50 = 2.931; 6.449 µg/mL); tyrosinase (8.092; 27.573) and elastase (43.342; 86.548). Additionally, the total antioxidant capacities measured as FRAP (4816.31 ± 7.42; 3584.17 ± 0.54) µM AAE/g, and ORAC for hydroxyl radical (7.265 ± 0.71; 6.779 ± 3.40) × 106 and peroxyl radical (17.836 ± 2.90; 12.545 ± 5.07) × 103 µM TE/g were also observed for compounds 7 and 8, respectively. In conclusion, H. teretifolium total extract represents a rich source of bioactive constituents with potent antioxidant and moderate anti-tyrosinase and anti-elastase activities that can help to avert accumulation of free radicals in the body, and could therefore be good candidates for the prevention and/or treatment of skin-related conditions, such as aging. This is the first scientific report on the chemical and biological profile of H. teretifolium.

  12. Embryo yolk sac membrane kynurenine formamidase of l-tryptophan to NAD+ pathway as a primary target for organophosphorus insecticides (OPI) in OPI-induced NAD-associated avian teratogenesis.

    Science.gov (United States)

    Seifert, Josef

    2017-10-01

    The objective of this study was to provide in ovo evidence for the proposed role of kynurenine formamidase of l-tryptophan to NAD + pathway in embryo yolk sac membranes as a primary target for organophosphorus insecticide (OPI) teratogens in OPI-induced NAD-associated avian teratogenesis. Slices prepared from yolk sac membranes or embryo livers of chicken eggs treated with the OPI dicrotophos and/or methyl parathion were incubated with l-tryptophan. Yolk sac membrane slices metabolized l-tryptophan in the pathway to NAD + before that function was established in livers. OPI interfered in ovo with the second step of l-tryptophan to NAD + biosynthesis by inhibiting kynurenine formamidase. Its inhibition due to the teratogen dicrotophos occurred in yolk sac membranes during the period of embryo highest susceptibility to OPI teratogens in contrast to delayed and lower inhibition caused by the nonteratogen methyl parathion. Both OPI affected liver kynurenine formamidase in a similar manner. The onsets of liver enzyme inhibition, however, were delayed by about two days and occurred at the time of the reduced embryo susceptibility to teratogens. The early disruption of l-tryptophan metabolism and higher inhibition of kynurenine formamidase in yolk sac membranes may be the factors that determine action of OPI as teratogens in chicken embryos. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Inhibition of Oxidative Stress and Skin Aging-Related Enzymes by Prenylated Chalcones and Other Flavonoids from Helichrysum teretifolium

    Directory of Open Access Journals (Sweden)

    Olugbenga K. Popoola

    2015-04-01

    Full Text Available Ten flavonoid-related structures viz. heliteretifolin (1, isoxanthohumol (2, 2',4',6'-trihydroxy-3'-prenylchalcone (3, isoglabranin (4, glabranin (5, 7-methoxy-isoglabranin (6, quercetin (7, 4'-methoxyquercetin (8, 4'-methoxykaempferol (9 and mosloflavone (10 were isolated from a H. teretifolium methanolic extract and identified. One of them (compound 1 is reported for the first time from a natural source, while compounds 6, 8–10 were isolated for the first time from the genus Helichrysum. The total extract of H. teretifolium showed potent antioxidant activity. When tested for total antioxidant capacity compound 3 possesses moderate biological activity compared to 2, which displayed some of the highest TEAC values (4529.01 ± 2.44; 4170.66 ± 6.72 µM TE/g, respectively. Compounds 7 and 8 demonstrated the highest inhibitory activities on Fe2+-induced lipid peroxidation (IC50 = 2.931; 6.449 µg/mL; tyrosinase (8.092; 27.573 and elastase (43.342; 86.548. Additionally, the total antioxidant capacities measured as FRAP (4816.31 ± 7.42; 3584.17 ± 0.54 µM AAE/g, and ORAC for hydroxyl radical (7.265 ± 0.71; 6.779 ± 3.40 × 106 and peroxyl radical (17.836 ± 2.90; 12.545 ± 5.07 × 103 µM TE/g were also observed for compounds 7 and 8, respectively. In conclusion, H. teretifolium total extract represents a rich source of bioactive constituents with potent antioxidant and moderate anti-tyrosinase and anti-elastase activities that can help to avert accumulation of free radicals in the body, and could therefore be good candidates for the prevention and/or treatment of skin-related conditions, such as aging. This is the first scientific report on the chemical and biological profile of H. teretifolium.

  14. Establishment of Exposure to Organophosphorus Warfare Agents by Means of SPME-GSMS Analysis of Bodily Fluids

    International Nuclear Information System (INIS)

    Saveleva, E. I.; Koryagina, N. L.; Radilov, A. S.; Khlebnikova, N. S.; Khrustaleva, V. S.; Feld, V. E.

    2007-01-01

    Reliable chemical analytical procedures for revealing an exposure to toxic chemicals, identifying the active substance, and assessing the degree of exposure are necessary as a component of medical and forensic activities in cases of the possible use of highly toxic chemicals in war conflicts and terrorism acts, as well as emergency situations in chemical industry, specifically at chemical weapons storage and destruction facilities. According to Chemical Weapons Convention, Part XI, Appendix 4, e-17, 'samples of importance in the investigation of alleged use include biomedical samples from human or animal sources (blood, urine, excreta, tissue etc.)'. Urinary metabolites, O-alkyl esters of methylphosphic acid, offer one of the simplest means of confirming an exposure to organophosphorus warfare agents (OPWA). Urine, unlike blood or tissues, does not require invasive collection demanding in terms of sterility. Excretion with urine is the major route of elimination of OPWA from an organism. According to published data, 90% of OPWA metabolites are excreted within 48-72 h after intoxication. We developed an SPME-GCMS procedure for the determination of O-alkyl esters methylphosphonic acid in urine, with the following detection limits,: isopropyl and isobutyl esters 5 ng/ml and pinacolyl ester 1 ng/ml. The procedure involves derivatization of the target compounds directly on the microfiber. The total analysis time is 1-1.5 h. In animal experiments in vivo we could establish the exposure to OPWA at a half-LD50 level within no less than 48 h after intoxication. In principle, OPWA metabolites could be detected in urine within two weeks after intoxication but at higher doses. Retrospective analysis of urinary metabolites in cases of the exposure to low doses of OPWA requires lower detection limits (0.1-1 ng/ml). Optimal objects for the retrospective analysis of OPWA in an organism are long-lived blood protein adducts. We developed a procedure for revealing an exposure to

  15. Recent Developments in Organophosphorus Flame Retardants Containing P-C Bond and Their Applications

    Directory of Open Access Journals (Sweden)

    Sophie Wendels

    2017-07-01

    Full Text Available Organophosphorus compounds containing P-C bonds are increasingly developed as flame retardant additives due to their excellent thermal and hydrolytic stability and ease of synthesis. The latest development (since 2010 in organophosphorus flame retardants containing P-C bonds summarized in this review. In this review, we have broadly classified such phosphorus compounds based on the carbon unit linked to the phosphorus atom i.e., could be a part of either an aliphatic or an aromatic unit. We have only considered those published literature where a P-C bond was created as a part of synthetic strategy to make either an intermediate or a final organophosphorus compound with an aim to use it as a flame retardant. General synthetic strategies to create P-C bonds are briefly discussed. Most popular synthetic strategies used for developing P-C containing phosphorus based flame retardants include Michael addition, Michaelis–Arbuzov, Friedels–Crafts and Grignard reactions. In general, most flame retardant derivatives discussed in this review have been prepared via a one- to two-step synthetic strategy with relatively high yields greater than 80%. Specific examples of P-C containing flame retardants synthesized via suitable synthetic strategy and their applications on various polymer systems are described in detail. Aliphatic phosphorus compounds being liquids or low melting solids are generally applied in polymers via coatings (cellulose or are incorporated in the bulk of the polymers (epoxy, polyurethanes during their polymerization as reactive or non-reactive additives. Substituents on the P atoms and the chemistry of the polymer matrix greatly influence the flame retardant behavior of these compounds (condensed phase vs. the gas phase. Recently, aromatic DOPO based phosphinate flame retardants have been developed with relatively higher thermal stabilities (>250 °C. Such compounds have potential as flame retardants for high temperature processable

  16. Trace Detection of Organophosphorus Chemical Warfare Agents in Wastewater and Plants by Luminescent UIO-67(Hf) and Evaluating the Bioaccumulation of Organophosphorus Chemical Warfare Agents.

    Science.gov (United States)

    Lian, Xiao; Yan, Bing

    2018-05-02

    Organophosphorus chemical warfare agents (OPCWAs) are a group of organic pollutants characterized by high toxicity and chemical stability, and they are very difficult to be degraded. The trace quality of OPCWAs in water and food will cause great harm to the human body. Therefore, the detection of OPCWAs is a difficult challenge, which has become the research hotspot over the world. In this work, a Hf-based luminescent metal-organic framework (Eu@1) is prepared, and the reactivity of Hf 12 results in a methanephosphonic acid (MPA)-induced luminescence quenching and the charge transfer from MPA to Hf(IV) and generated exciplexes which are responsible for this quenching effect. The excellent performance of Eu@1 in the detection of MPA, with its finer selectivity, high sensitivity (LOD = 0.4 ppm), and large linear range (10 -7 to 10 -3 M), is encouraging for application in wastewater detection. Importantly, MPA is a pollutant that can be absorbed by plants and causes the bioaccumulation effect, and thus, the detection of MPA in real plant samples is a purposeful topic. Eu@1 also achieved satisfactory results in actual plant sample testing, and the bioaccumulation of MPA in onions, turnips, and cabbages is determined via our sensor. This fabricated detector provides a feasible path for the detection of ppm-level OPCWAs in a complex environment, which will help humans to avoid OPCWA-contaminated foods.

  17. Estimation of solubility of organo-phosphorus extractants by P determination using molybdovanadophosphoric acid method

    International Nuclear Information System (INIS)

    Gill, J.S.; Kotekar, M.K.; Singh, H.

    2005-01-01

    Solvent extraction processes have been found to be suitable for uranium recovery from phosphoric acid. Various extractants like di-2-ethyl hexylphosphoric acid (D2EHPA), di-nonylphenyl phosphoric acid (DNPPA) and synergistic agents like tri-butyl phosphate (TBP), tri-octyl phosphine oxide (TOPO) have been used in liquid-liquid extraction of uranium from phosphoric acid. Contents of these organo-phosphorus compounds in aqueous raffinates need estimation for process requirements. Solubility of Tri-butyl phosphate (TBP) and Di-2-ethylhexyl phosphoric acid (D2EHPA) extractants have been determined in different media of water, oxalic acid (0.6M) and sulphuric acid (3.75M) solutions. These compounds were estimated by determining their phosphorus (P) contents employing molybdovanadophosphoric acid method, after digesting and solubalizing them in nitric and perchloric acid. (author)

  18. Concentration of Organochlorine and Organophosphorus Pesticides in Different Molluscs from Tighra Reservoir, Gwalior, India.

    Science.gov (United States)

    Mamta; Rao, R J; Wani, Khursheed Ahmad

    2015-09-01

    Concentration of organochlorine and organophosphorus pesticides and their metabolites were determined in whole body homogenate of L. acuminata, I. exustus, V. dissimilis, V. bengalensis, from Tighra Reservoir during summer and post monsoon season using GC-MS technique. The different types of pesticides viz., HCB, heptachlor, aldrin, endosulfan, dieldrin, p,p-DDT, choloropyrifos, methyl parathion, dicholorovos, ethion, malathion, parathion were found in resident molluscs studied. Concentration of these pesticides varied independently during the summer and the post monsoon season at monitored sites. The study concluded that presence of pesticides in Tighra Reservoir is a major concern on public and ecosystem health and use of biopesticides in the adjacent area of Reservoir is highly recommended.

  19. Electrochemical process for the treatment of water contaminated with organophosphorus pesticides

    International Nuclear Information System (INIS)

    Samet, Youssef; Agengui, Lamia; Abdelhedi, Ridha

    2009-01-01

    The aim of this work is the use of electrochemical process for the total mineralization of water contaminated with organophosphorus pesticides like chloropyrifos. This pesticide is widely used both for agricultural pest control and in households as a termiticide. The process was studied under galvanostatic polarization mode using Ta/PbO 2 anodes and graphite carbon bar as cathode. The kinetic of organic matter decay and the mineralization efficiency were evaluated by means of the chemical oxygen demand (COD) measurement. The influence of the experimental parameters such as the initial concentration of chloropyrifos, temperature, and current density, on the electrochemical process performance was investigated. The experimental results showed that COD removal always follows a pseudo-first-order kinetics. The degradation rate increased drastically with increasing current density and temperature. However, it decreased with the increase of the initial pollutant concentrations. Very high organic matter degradation, approximately 90 pour cent in 10 h experiments, was obtained.

  20. Degradation kinetics of seven organophosphorus pesticides in milk during yoghurt processing

    Directory of Open Access Journals (Sweden)

    LI-YING BO

    2011-03-01

    Full Text Available Bovine milk spiked with seven organophosphorus pesticides, i.e., dimethoate, fenthion, malathion, methyl parathion, monocrotophos, phorate and trichlorphon, was fermented at 42 °C with commercial directed vat set (DVS starters to investigate the degradation kinetics of the pesticides during yoghurt processing. The spiked pesticides were extracted from the prepared samples with an organic solvent and analyzed by gas chromatography after purification. Based on published results that the degradation kinetics of pesticides is first order, the rate constant of degradation and the half live period of the pesticides were calculated. The results indicated that degradation of the pesticides in milk during yoghurt processing were enhanced by one or both starters, except for malathion, and the two commercial DVS starters had different influences on the degradation kinetics of the pesticides.

  1. Is the stoichiometry of the europium nitrate complexes with neutral organophosphorus extractants be anticipated?

    International Nuclear Information System (INIS)

    Beudaert, Ph.; Lamare, V.; Wipff, G.

    2001-01-01

    Molecular dynamics simulations have been performed in water on europium nitrate complexes with three neutral organophosphorus extractants (TBP, TPPO and CMPO) in order to determine on what criteria it is possible to obtain by simulations the experimental 1:3 stoichiometry in organic solution. This stoichiometry was investigated by progressive saturation of the cation coordination sphere. When the nitrate counter-ions are bidentate, the 1:3 stoichiometry corresponds to the degree of saturation where the interaction energy between europium and water becomes repulsive. Beyond this stoichiometry, complexes with TPPO and CMPO are unstable, although a 1:4 complex with TBP may exist but its formation appears to be energetically unfavored. (author)

  2. Influence of modifiers on the separation of dysprosium from neodymium using organophosphorus acid derivates

    Energy Technology Data Exchange (ETDEWEB)

    Elwert, Tobias; Schwarz, Sabrina; Goldmann, Daniel [TU Clausthal, Clausthal-Zellerfeld (Germany). Lehrstuhl fuer Rohstoffaufbereitung und Recycling

    2016-01-15

    The aim of this study was to investigate the applicability of three organophosphorus acid derivates (D2EHPA, EHEHPA and Cyanex 572) for the separation of terbium and dysprosium from praseodymium and neodymium from NdFeB magnets in chloride solution. A special focus was put on the effect of phase modifiers. The investigations revealed that all extractants show in general a similar extraction behavior but the extraction is shifted to higher pH values in the order D2EHPA < EHEHPA < Cyanex 572. Therefore, and due to higher realizable loadings, EHEHPA and Cyanex 572 are more suitable for the investigated separation problem than D2EHPA. Whereas EHEHPA requires 1-decanol as phase modifier, Cyanex 572 can be employed without modifier addition.

  3. Nicotine And The Risk Of Exposure To The Organophosphorus Insecticide Cyolane

    International Nuclear Information System (INIS)

    Hassanin M, M.; Bahig Mervat, E.

    1999-01-01

    The present investigation was undertaken to show the effect of repeated oral doses of nicotine (0.5 mg/kg) on rats pretreated or during treatment with cyolane (0.5 mg/kg 1/20 LD 5 0). The results revealed that exposure of smokers to organophosphorus pesticides exerted slight changes in GOT and GPT. Alkaline phosphatase was significantly increased to reach maximal (228.54 and 148.64%) after nicotine + cyolane and/or nicotine were given for a week to rats pretreated with cyolane for 2 weeks. Total protein, albumin and Albumin/Globulin (A/G) ratio were also affected. Administration of nicotine along with cyolane to rats showed a significant increase in cholesterol content compared to that of cyolane treated rats. Values of thyroxine (T 4 ) and triiodothyronine (T 3 ) also fluctuated

  4. Multipathway organophosphorus pesticide exposures of preschool children living in agricultural and nonagricultural communities

    International Nuclear Information System (INIS)

    Lu Chensheng; Kedan, Golan; Fisker-Andersen, Jennifer; Kissel, J.C.; Fenske, R.A.

    2004-01-01

    Environmental measurements of organophosphorus (OP) pesticides were conducted in the homes of 13 children, who lived either in the Seattle metropolitan area or in the agricultural region of Washington State, to ascertain exposure through multiple pathways. Each home was sampled for two 24-h periods during two seasons, summer and fall. Samples included 24-h indoor air, drinking water, soil, house dust, and hand and toy wipes and 24-h duplicate diets. At least one OP pesticide was found in each of the matrices sampled except for drinking water. Half of the indoor air samples contained detectable levels of chlorpyrifos or diazinon. Detectable levels of diazinon and azinphosmethyl in house dust were found in most of the agricultural homes, whereas only diazinon was found in the Seattle homes in the summer. Quantifiable chlorpyrifos and azinphosmethyl were found on either agricultural children's hands or their toys. These findings suggest different exposure pathways for children living in agricultural and nonagricultural regions

  5. Engineering and introduction of de novo disulphide bridges in organophosphorus hydrolase enzyme for thermostability improvement.

    Science.gov (United States)

    Farnoosh, Gholamreza; Khajeh, Khosro; Latifi, Ali Mohammad; Aghamollaei, Hossein

    2016-12-01

    The organophosphorus hydrolase (OPH) has been used to degrade organophosphorus chemicals, as one of the most frequently used decontamination methods. Under chemical and thermal denaturing conditions, the enzyme has been shown to unfold. To utilize this enzyme in various applications, the thermal stability is of importance. The engineering of de novo disulphide bridges has been explored as a means to increase the thermal stability of enzymes in the rational method of protein engineering. In this study, Disulphide by Design software, homology modelling and molecular dynamics simulations were used to select appropriate amino acid pairs for the introduction of disulphide bridge to improve protein thermostability. The thermostability of the wild-type and three selected mutant enzymes were evaluated by half-life, delta G inactivation (ΔGi) and structural studies (fluorescence and far-UV CD analysis). Data analysis showed that half-life of A204C/T234C and T128C/E153C mutants were increased up to 4 and 24 min, respectively; however, for the G74C/A78C mutant, the half-life was decreased up to 9 min. For the T128C/E124C mutant, both thermal stability and Catalytic efficiency (kcat) were also increased. The half-life and ΔGi results were correlated to the obtained information from structural studies by circular dichroism (CD) spectrometry and extrinsic fluorescence experiments; as rigidity increased in A204C/T2234C and T128C/E153C mutants, half-life and ΔGi also increased. For G74C/A78C mutant, these parameters decreased due to its higher flexibility. The results were submitted a strong evidence for the possibility to improve the thermostability of OPH enzyme by introducing a disulphide bridge after bioinformatics design, even though this design would not be always successful.

  6. The solvent extraction of zinc, iron, and indium from chloride solutions by neutral organophosphorus compounds

    International Nuclear Information System (INIS)

    Preston, J.S.; Du Preez, A.C.

    1985-01-01

    The preparation of several neutral organophosphorus compounds and their evaluation as selective extractants for zinc in chloride media are described. The compounds belong to the series trialkyl phosphates (RO) 3 PO, dialkyl alkylphosphonates R'PO(OR) 2 , alkyl dialkylphosphinates R 2 'PO(OR), and trialkyl-phosphine oxides R 3 'PO. They were characterized by measurement of their physical properties (melting and boiling points, refractive indices, and densities), and their purities were confirmed by osmometric determination of their molecular masses; by carbon and hydrogen microanalysis; by the titrimetric determination of acidic impurities; and, for liquid products, by comparison of their experimental molar refractivities with empirical values. Metal-distribution equilibria were determined for solutions of the extractants in xylene and aqueous phase containing 0,5 to 5,0 M sodium chloride. Moderately good selectivities were shown for zinc(II) over iron(III), and excellent selectivities were shown for zinc(II) over iron(II), copper(II), lead(II), and cadmium(II). The extraction of indium(III) was similar to that of zinc(II). The extraction of zinc(III), iron(III), and indium(III) increased markedly through the series. (RO) 3 PO 2 2 'PO(OR) 3 'PO. The incorporation of phenyl groups into the compounds led to weaker extraction. The extracted complexes of zinc(II), iron(III), and indium(III) have the stoichiometries ZnCl 2 L 2 ,FeCl 3 L 2 (H 2 O), and InCl 3 L 2 (H 2 O) respectively, where L represents the neutral organophosphorus compound

  7. Shanxi Aged Vinegar Protects against Alcohol-Induced Liver Injury via Activating Nrf2-Mediated Antioxidant and Inhibiting TLR4-Induced Inflammatory Response

    Directory of Open Access Journals (Sweden)

    Ting Xia

    2018-06-01

    Full Text Available Shanxi aged vinegar (SAV is a typical fermented and antioxidant food, which has various health-promoting effects. This work aimed to explore the effects of SAV on alcohol-induced liver injury. A mice model of alcoholic liver injury was established to illuminate its potential mechanisms. All mice pretreated with SAV and then received an ethanol solution (50% w/v, 4.8 g/kg b.w.. The results showed that SAV ameliorated alcohol-induced histological changes and elevation of liver enzymes. SAV attenuated alcohol-induced oxidative stress by declining levels of hepatic oxidants, and restoring depletion of antioxidant enzyme activities in mice livers. Moreover, SAV alleviated alcohol-induced oxidative damage by activating nuclear factor erythroid-2-related factor 2 (Nrf2-mediated signal pathway. In addition, SAV prevented alcohol-induced inflammation by suppressing lipopolysaccharide (LPS level and activities of pro-inflammatory enzymes, and regulating inflammatory cytokines. SAV inhibited alcohol-induced inflammation through down-regulating the expression of Toll-like receptor 4 (TLR4-mediated inflammatory response. The findings provide crucial evidence for elucidating the hepatoprotective mechanisms of SAV and encourage the future application of SAV as a functional food for liver protection.

  8. 12/15-Lipoxygenase Inhibition Reverses Cognitive Impairment, Brain Amyloidosis, and Tau Pathology by Stimulating Autophagy in Aged Triple Transgenic Mice.

    Science.gov (United States)

    Di Meco, Antonio; Li, Jian-Guo; Blass, Benjamin E; Abou-Gharbia, Magid; Lauretti, Elisabetta; Praticò, Domenico

    2017-01-15

    The 12/15-lipoxygenase (12/15-LO) enzyme is upregulated in the brains of patients with Alzheimer's disease (AD), and its expression levels influence the onset of the AD-like phenotype in mouse models. However, whether targeting this pathway after the neuropathology and behavioral impairments have been established remains to be investigated. Triple transgenic (3xTg) mice received either PD146176-a selective and specific pharmacological inhibitor of 12/15-LO-or placebo starting at 12 months of age for 12 weeks. They were then assessed for the effect of the treatment on neuropathologies and behavioral impairments. At the end of the study, mice in the control group showed a worsening of memory and learning abilities, whereas mice receiving PD146176 were undistinguishable from wild-type mice. The same group also had significantly lower amyloid beta levels and deposition, less tau neuropathology, increased synaptic integrity, and autophagy activation. Ex vivo and in vitro genetic and pharmacological studies found that the mechanism involved in these effects was the activation of neuronal autophagy. Our findings provide new insights into the disease-modifying action of 12/15-LO pharmacological inhibition and establish it as a viable therapeutic approach for patients with AD. Copyright © 2016 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  9. Influence of age, body temperature, GABAA receptor inhibition and caffeine on the Hering-Breuer inflation reflex in unanesthetized rat pups.

    Science.gov (United States)

    Arnal, Ashley V; Gore, Julie L; Rudkin, Alison; Bartlett, Donald; Leiter, J C

    2013-03-01

    We measured the duration of apnea induced by sustained end-inspiratory lung inflation (the Hering Breuer Reflex, HBR) in unanesthetized infant rat pups aged 4 days (P4) to P20 at body temperatures of 32°C and 36°C. The expiratory prolongation elicited by the HBR lasted longer in the younger pups and lasted longer at the higher body temperature. Blockade of adenosine receptors by caffeine following injection into the cisterna magna (ICM) significantly blunted the thermal prolongation of the HBR. Blockade of gama-amino-butyric acid A (GABAA) receptors by pre-treatment with ICM bicuculline had no effect on the HBR duration at either body temperature. To test the hypothesis that developmental maturation of GABAergic inhibition of breathing was modifying the response to bicuculline, we pretreated rat pups with systemically administered bumetanide to lower the intracellular chloride concentration, and repeated the bicuculline studies. Bicuculline still did not alter the HBR at either temperature after bumetanide treatment. We administered PSB-36, a selective adenosine A1 receptor antagonist, and this drug treatment did not modify the HBR. We conclude that caffeine blunts the thermal prolongation of the HBR, probably by blocking adenosine A2a receptors. The thermally sensitive adenosinergic prolongation of the HBR in these intact animals does not seem to depend on GABAA receptors. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Synergistic Extraction of Copper from Nitrate Solutions Using β-Hydroxy-Naphthaldoxime and Organophosphorus Compounds into Carbon-Tetrachloride

    Science.gov (United States)

    Dey, Pulak; Basu, Sukalyan

    2011-12-01

    The extraction behavior of Cu(II) from an aqueous nitrate medium employing β-hydroxy-naphthaldoxime in carbon tetrachloride has been investigated in the presence of several organophosphorus donors like tri-octyl phosphine oxide, tri-butyl phosphine oxide, and tri-butyl phosphate at pH 1.5. The concentration of the metal was measured by atomic absorption spectrophotometry. Synergism was observed when neutral donor was added because of the formation of the adduct [Cu(L)2.(S)] in CCl4 (S denotes neutral donor). The equilibrium constants of the binary system using β-hydroxy-naphthaldoxime and the ternary system involving another addition of an organophosphorus compound were calculated from the extraction date obtained. Furthermore, the temperature dependence of the equilibrium constants was also investigated to evaluate standard enthalpy (Δ H°), entropy (Δ S°), and free energy (Δ G°) of the reactions proposed.

  11. Expression of organophosphorus-degradation gene ( opd) in aggregating and non-aggregating filamentous nitrogen-fixing cyanobacteria

    Science.gov (United States)

    Li, Qiong; Tang, Qing; Xu, Xudong; Gao, Hong

    2010-11-01

    Genetic engineering in filamentous N2-fixing cyanobacteria usually involves Anabaena sp. PCC 7120 and several other non-aggregating species. Mass culture and harvest of such species are more energy consuming relative to aggregating species. To establish a gene transfer system for aggregating species, we tested many species of Anabaena and Nostoc, and identified Nostoc muscorum FACHB244 as a species that can be genetically manipulated using the conjugative gene transfer system. To promote biodegradation of organophosphorus pollutants in aquatic environments, we introduced a plasmid containing the organophosphorus-degradation gene ( opd) into Anabaena sp. PCC 7120 and Nostoc muscorum FACHB244 by conjugation. The opd gene was driven by a strong promoter, P psbA . From both species, we obtained transgenic strains having organophosphorus-degradation activities. At 25°C, the whole-cell activities of the transgenic Anabaena and Nostoc strains were 0.163±0.001 and 0.289±0.042 unit/μg Chl a, respectively. However, most colonies resulting from the gene transfer showed no activity. PCR and DNA sequencing revealed deletions or rearrangements in the plasmid in some of the colonies. Expression of the green fluorescent protein gene from the same promoter in Anabaena sp. PCC 7120 showed similar results. These results suggest that there is the potential to promote the degradation of organophosphorus pollutants with transgenic cyanobacteria and that selection of high-expression transgenic colonies is important for genetic engineering of Anabaena and Nostoc species. For the first time, we established a gene transfer and expression system in an aggregating filamentous N2-fixing cyanobacterium. The genetic manipulation system of Nostoc muscorum FACHB244 could be utilized in the elimination of pollutants and large-scale production of valuable proteins or metabolites.

  12. [Determination of 44 organophosphorus pesticides in food by SPE disk extraction-capillary gas chromatography with pulsed flame photometric detection].

    Science.gov (United States)

    Luo, Xiao-Fei; Yang, Yuan; Sun, Cheng-Jun

    2012-01-01

    To develop a method for the simultaneous determination of 44 organophosphorus pesticides in food by SPE disk extraction-capillary gas chromatography with pulsed flame photometric detection. Organophosphorus pesticides in food were extracted ultrasonically with water. Then the extract was cleaned-up with SPE disk and eluted with ethyl acetate. Finally the eluent was condensed to 1mL under N2 at 55 degrees C. Gas chromatography was applied for quantitative detection of the organophosphorus pesticides in the sample. The linear range of the method for all the pesticides were in the range of 0.01-0.5 mg/kg with correlation coefficients of 0.992-1.000. The detection limits of the method were in the range of 0.0005-0.01 mg/kg. The recoveries for most pesticides were 60%-120% with relative standard deviations of less than 15%. The method is simple, sensitive, environmentally friendly and suitable for the determination of organophosphorous pesticides in food.

  13. An amperometric biosensor based on acetylcholinesterase immobilized onto iron oxide nanoparticles/multi-walled carbon nanotubes modified gold electrode for measurement of organophosphorus insecticides

    Energy Technology Data Exchange (ETDEWEB)

    Chauhan, Nidhi [Department of Biochemistry, M.D. University, Rohtak 124001, Haryana (India); Pundir, Chandra Shekhar, E-mail: pundircs@rediffmail.com [Department of Biochemistry, M.D. University, Rohtak 124001, Haryana (India)

    2011-09-02

    Graphical abstract: The stepwise amperometric biosensor fabrication process and immobilized acetylcholinesterase inhibition in pesticide solution. Highlights: {center_dot} Constructed a novel composite material using Fe{sub 3}O{sub 4}NP and c-MWCNT at Au electrode for electrocatalysis. {center_dot} The properties of nanoparticles modified electrodes were studied by SEM, FTIR, CVs and EIS. {center_dot} The biosensor exhibited good sensitivity (0.475 mA {mu}M{sup -1}) {center_dot} The half life of electrode was 2 months. {center_dot} The sensor was suitable for trace detection of OP pesticide residues in milk and water. - Abstract: An acetylcholinesterase (AChE) purified from maize seedlings was immobilized covalently onto iron oxide nanoparticles (Fe{sub 3}O{sub 4}NP) and carboxylated multi walled carbon nanotubes (c-MWCNT) modified Au electrode. An organophosphorus (OP) biosensor was fabricated using this AChE/Fe{sub 3}O{sub 4}/c-MWCNT/Au electrode as a working electrode, Ag/AgCl as standard and Pt wire as an auxiliary electrode connected through a potentiostat. The biosensor was based on inhibition of AChE by OP compounds/insecticides. The properties of nanoparticles modified electrodes were studied by scanning electron microscopy (SEM), Fourier transform infrared (FTIR), cyclic voltammograms (CVs) and electrochemical impedance spectroscopy (EIS). The synergistic action of Fe{sub 3}O{sub 4}NP and c-MWCNT showed excellent electrocatalytic activity at low potential (+0.4 V). The optimum working conditions for the sensor were pH 7.5, 35 deg. C, 600 {mu}M substrate concentration and 10 min for inhibition by pesticide. Under optimum conditions, the inhibition rates of OP pesticides were proportional to their concentrations in the range of 0.1-40 nM, 0.1-50 nM, 1-50 nM and 10-100 nM for malathion, chlorpyrifos, monocrotophos and endosulfan respectively. The detection limits were 0.1 nM for malathion and chlorpyrifos, 1 nM for monocrotophos and 10 nM for endosulfan. The

  14. Kinetics of the inhibitory interaction of organophosphorus neuropathy inducers and non-inducers in soluble esterases in the avian nervous system

    Energy Technology Data Exchange (ETDEWEB)

    Mangas, Iris; Vilanova, Eugenio; Estevez, Jorge, E-mail: jorge.estevez@umh.es

    2011-11-15

    Some published studies suggest that low level exposure to organophosphorus esters (OPs) may cause neurological and neurobehavioral effects at long term exposure. These effects cannot be explained by action on known targets. In this work, the interactions (inhibition, spontaneous reactivation and 'ongoing inhibition') of two model OPs (paraoxon, non neuropathy-inducer, and mipafox, neuropathy-inducer) with the chicken brain soluble esterases were evaluated. The best-fitting kinetic model with both inhibitors was compatible with three enzymatic components. The amplitudes (proportions) of the components detected with mipafox were similar to those obtained with paraoxon. These observations confirm the consistency of the results and the model applied and may be considered an external validation. The most sensitive component (E{alpha}) for paraoxon (11-23% of activity, I{sub 50} (30 min) = 9-11 nM) is also the most sensitive for mipafox (I{sub 50} (30 min) = 4 nM). This component is spontaneously reactivated after inhibition with paraoxon. The second sensitive component to paraoxon (E{beta}, 71-84% of activity; I{sub 50} (30 min) = 1216 nM) is practically resistant to mipafox. The third component (E{gamma}, 5-8% of activity) is paraoxon resistant and has I{sub 50} (30 min) of 3.4 {mu}M with mipafox, similar to NTE (neuropathy target esterase). The role of these esterases remains unknown. Their high sensitivity suggests that they may either play a role in toxicity in low-level long-term exposure of organophosphate compounds or have a protective effect related with the spontaneous reactivation. They will have to be considered in further metabolic and toxicological studies. -- Research Highlights: Black-Right-Pointing-Pointer Paraoxon and mipafox interactions have been evaluated with chicken soluble brain esterases. Black-Right-Pointing-Pointer The paraoxon inhibition was analyzed considering the simultaneous spontaneous reactivation. Black

  15. [Research on rapid and quantitative detection method for organophosphorus pesticide residue].

    Science.gov (United States)

    Sun, Yuan-Xin; Chen, Bing-Tai; Yi, Sen; Sun, Ming

    2014-05-01

    The methods of physical-chemical inspection is adopted in the traditional pesticide residue detection, which require a lot of pretreatment processes, are time-consuming and complicated. In the present study, the authors take chlorpyrifos applied widely in the present agricultural field as the research object and propose a rapid and quantitative detection method for organophosphorus pesticide residues. At first, according to the chemical characteristics of chlorpyrifos and comprehensive chromogenic effect of several colorimetric reagents and secondary pollution, the pretreatment of the scheme of chromogenic reaction of chlorpyrifos with resorcin in a weak alkaline environment was determined. Secondly, by analyzing Uv-Vis spectrum data of chlorpyrifos samples whose content were between 0. 5 and 400 mg kg-1, it was confirmed that the characteristic information after the color reaction mainly was concentrated among 360 approximately 400 nm. Thirdly, the full spectrum forecasting model was established based on the partial least squares, whose correlation coefficient of calibration was 0. 999 6, correlation coefficient of prediction reached 0. 995 6, standard deviation of calibration (RMSEC) was 2. 814 7 mg kg-1, and standard deviation of verification (RMSEP) was 8. 012 4 mg kg-1. Fourthly, the wavelengths whose center wavelength is 400 nm was extracted as characteristic region to build a forecasting model, whose correlation coefficient of calibration was 0. 999 6, correlation coefficient of prediction reached 0. 999 3, standard deviation of calibration (RMSEC) was 2. 566 7 mg kg-1 , standard deviation of verification (RMSEP) was 4. 886 6 mg kg-1, respectively. At last, by analyzing the near infrared spectrum data of chlorpyrifos samples with contents between 0. 5 and 16 mg kg-1, the authors found that although the characteristics of the chromogenic functional group are not obvious, the change of absorption peaks of resorcin itself in the neighborhood of 5 200 cm

  16. Gastric Lavage in Acute Organophosphorus Pesticide poisoning (GLAOP – a randomised controlled trial of multiple vs. single gastric lavage in unselected acute organophosphorus pesticide poisoning

    Directory of Open Access Journals (Sweden)

    Cao YuPing

    2006-10-01

    Full Text Available Abstract Background Organophosphorus (OP pesticide poisoning is the most common form of pesticide poisoning in many Asian countries. Guidelines in western countries for management of poisoning indicate that gastric lavage should be performed only if two criteria are met: within one hour of poison ingestion and substantial ingested amount. But the evidence on which these guidelines are based is from medicine overdoses in developed countries and may be irrelevant to OP poisoning in Asia. Chinese clinical experience suggests that OP remains in the stomach for several hours or even days after ingestion. Thus, there may be reasons for doing single or multiple gastric lavages for OP poisoning. There have been no randomised controlled trials (RCTs to assess this practice of multiple lavages. Since it is currently standard therapy in China, we cannot perform a RCT of no lavage vs. a single lavage vs. multiple lavages. We will compare a single gastric lavage with three gastric lavages as the first stage to assess the role of gastric lavage in OP poisoning. Methods/Design We have designed an RCT assessing the effectiveness of multiple gastric lavages in adult OP self-poisoning patients admitted to three Chinese hospitals within 12 hrs of ingestion. Patients will be randomised to standard treatment plus either a single gastric lavage on admission or three gastric lavages at four hour intervals. The primary outcome is in-hospital mortality. Analysis will be on an intention-to-treat basis. On the basis of the historical incidence of OP at the study sites, we expect to enroll 908 patients over three years. This projected sample size provides sufficient power to evaluate the death rate; and a variety of other exposure and outcome variables, including particular OPs and ingestion time. Changes of OP level will be analyzed in order to provide some toxic kinetic data. Discussion the GLAOP study is a novel, prospective cohort study that will explore to the toxic

  17. Induction of epithelial to mesenchymal transition (EMT) and inhibition on adipogenesis: Two different sides of the same coin? Feasible roles and mechanisms of transforming growth factor β1 (TGF-β1) in age-related thymic involution.

    Science.gov (United States)

    Tan, Jianxin; Wang, Yajun; Zhang, Nannan; Zhu, Xike

    2016-08-01

    Age-related thymic involution is characterized by a loss of thymic epithelial cells (TECs) and a concomitant increase in adipocytes, but the mechanisms involved in thymic adipogenesis are still not clear. Transforming growth factor β1 (TGF-β1) is a pleiotropic cytokine that has been reported to be up-regulated with age in thymic stromal cells in both human and mouse. However, the exact role of TGF-β1 in age-related thymic involution remains to be further elucidated. On the basis of previous findings, we propose a novel hypothesis that TGF-β1 functions a dual role in age-related thymic involution. On one hand, up-regulation of TGF-β1 promotes epithelial to mesenchymal transition (EMT) process in TECs via activating forkhead box protein C2 (FoxC2). On the other hand, TGF-β1 inhibits the transdifferentiation of EMT-derived mesenchymal cells to adipocytes in the thymus. If confirmed, our hypothesis will not only provide further evidence supporting that the transdifferentiation of TECs into pre-adipocytes represents a source of thymic adiposity during age-related thymic involution, but also uncover a unique role of TGF-β1 in the transdifferentiation of TECs into pre-adipocytes. Collectively, the inhibition of TGF-β1 may serve as a strategy to hinder age-related thymic involution or even to restore thymic function in the elderly. © 2016 International Federation for Cell Biology.

  18. Kinetics of the inhibitory interaction of organophosphorus neuropathy inducers and non-inducers in soluble esterases in the avian nervous system

    International Nuclear Information System (INIS)

    Mangas, Iris; Vilanova, Eugenio; Estévez, Jorge

    2011-01-01

    Some published studies suggest that low level exposure to organophosphorus esters (OPs) may cause neurological and neurobehavioral effects at long term exposure. These effects cannot be explained by action on known targets. In this work, the interactions (inhibition, spontaneous reactivation and “ongoing inhibition”) of two model OPs (paraoxon, non neuropathy-inducer, and mipafox, neuropathy-inducer) with the chicken brain soluble esterases were evaluated. The best-fitting kinetic model with both inhibitors was compatible with three enzymatic components. The amplitudes (proportions) of the components detected with mipafox were similar to those obtained with paraoxon. These observations confirm the consistency of the results and the model applied and may be considered an external validation. The most sensitive component (Eα) for paraoxon (11–23% of activity, I 50 (30 min) = 9–11 nM) is also the most sensitive for mipafox (I 50 (30 min) = 4 nM). This component is spontaneously reactivated after inhibition with paraoxon. The second sensitive component to paraoxon (Eβ, 71–84% of activity; I 50 (30 min) = 1216 nM) is practically resistant to mipafox. The third component (Eγ, 5–8% of activity) is paraoxon resistant and has I 50 (30 min) of 3.4 μM with mipafox, similar to NTE (neuropathy target esterase). The role of these esterases remains unknown. Their high sensitivity suggests that they may either play a role in toxicity in low-level long-term exposure of organophosphate compounds or have a protective effect related with the spontaneous reactivation. They will have to be considered in further metabolic and toxicological studies. -- Research Highlights: ► Paraoxon and mipafox interactions have been evaluated with chicken soluble brain esterases. ► The paraoxon inhibition was analyzed considering the simultaneous spontaneous reactivation. ► The best-fitting kinetic models were compatible with a three enzymatic components. ► The amplitudes of the

  19. Organophosphorus flame retardants in mangrove sediments from the Pearl River Estuary, South China.

    Science.gov (United States)

    Hu, Yong-Xia; Sun, Yu-Xin; Li, Xiao; Xu, Wei-Hai; Zhang, Ying; Luo, Xiao-Jun; Dai, Shou-Hui; Xu, Xiang-Rong; Mai, Bi-Xian

    2017-08-01

    Forty-eight surface sediments were collected from three mangrove wetlands in the Pearl River Estuary (PRE) of South China to investigate the distribution of organophosphorus flame retardants (OPFRs) and the relationship between OPFRs and microbial community structure determined by phospholipid fatty acid. Concentrations of ΣOPFRs in mangrove sediments of the PRE ranged from 13.2 to 377.1 ng g -1 dry weight. Levels of ΣOPFRs in mangrove sediments from Shenzhen and Guangzhou were significantly higher than those from Zhuhai, indicating that OPFRs were linked to industrialization and urbanization. Tris(chloropropyl)phosphate was the predominant profile of OPFRs in mangrove sediments from Shenzhen (38.9%) and Guangzhou (35.0%), while the composition profile of OPFRs in mangrove sediments from Zhuhai was dominated by tris(2-chloroethyl) phosphate (25.5%). The mass inventories of OPFRs in the mangrove sediments of Guangzhou, Zhuhai and Shenzhen were 439.5, 133.5 and 662.3 ng cm -2 , respectively. Redundancy analysis revealed that OPFRs induced a shift in the structure of mangrove sediment microbial community and the variations were significantly correlated with tris(1,3-dichloro-2-propyl)phosphate and tris(2-butoxyethyl) phosphate. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Sensitive spectrophotometric methods for determination of some organophosphorus pesticides in vegetable samples

    Directory of Open Access Journals (Sweden)

    MAGDA A. AKL

    2010-03-01

    Full Text Available Three rapid, simple, reproducible and sensitive spectrophotometric methods (A, B and C are described for the determination of two organophosphorus pesticides, (malathion and dimethoate in formulations and vegetable samples. The methods A and B involve the addition of an excess of Ce4+ into sulphuric acid medium and the determination of the unreacted oxidant by decreasing the red color of chromotrope 2R (C2R at a suitable lmax = 528 nm for method A, or a decrease in the orange pink color of rhodamine 6G (Rh6G at a suitable lmax = = 525 nm. The method C is based on the oxidation of malathion or dimethoate with the slight excess of N-bromosuccinimide (NBS and the determination of unreacted oxidant by reacting it with amaranth dye (AM in hydrochloric acid medium at a suitable lmax = 520 nm. A regression analysis of Beer-Lambert plots showed a good correlation in the concentration range of 0.1-4.2 μg mL−1. The apparent molar absorptivity, Sandell sensitivity, the detection and quantification limits were calculated. For more accurate analysis, Ringbom optimum concentration ranges are 0.25-4.0 μg mL−1. The developed methods were successfully applied to the determination of malathion, and dimethoate in their formulations and environmental vegetable samples.

  1. Partitioning of organophosphorus pesticides into phosphatidylcholine small unilamellar vesicles studied by second-derivative spectrophotometry.

    Science.gov (United States)

    Takegami, Shigehiko; Kitamura, Keisuke; Ohsugi, Mayuko; Ito, Aya; Kitade, Tatsuya

    2015-06-15

    In order to quantitatively examine the lipophilicity of the widely used organophosphorus pesticides (OPs) chlorfenvinphos (CFVP), chlorpyrifos-methyl (CPFM), diazinon (DZN), fenitrothion (FNT), fenthion (FT), isofenphos (IFP), profenofos (PFF) and pyraclofos (PCF), their partition coefficient (Kp) values between phosphatidylcholine (PC) small unilamellar vesicles (SUVs) and water (liposome-water system) were determined by second-derivative spectrophotometry. The second-derivative spectra of these OPs in the presence of PC SUV showed a bathochromic shift according to the increase in PC concentration and distinct derivative isosbestic points, demonstrating the complete elimination of the residual background signal effects that were observed in the absorption spectra. The Kp values were calculated from the second-derivative intensity change induced by addition of PC SUV and obtained with a good precision of R.S.D. below 10%. The Kp values were in the order of CPFM>FT>PFF>PCF>IFP>CFVP>FNT⩾DZN and did not show a linear correlation relationship with the reported partition coefficients obtained using an n-octanol-water system (R(2)=0.530). Also, the results quantitatively clarified the effect of chemical-group substitution in OPs on their lipophilicity. Since the partition coefficient for the liposome-water system is more effective for modeling the quantitative structure-activity relationship than that for the n-octanol-water system, the obtained results are toxicologically important for estimating the accumulation of these OPs in human cell membranes. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Susceptibility of nine organophosphorus pesticides in skimmed milk towards inoculated lactic acid bacteria and yogurt starters.

    Science.gov (United States)

    Zhou, Xin-Wei; Zhao, Xin-Huai

    2015-01-01

    Previous research has shown that fresh milk might be polluted by some organophosphorus pesticides (OPPs). In this study the dissipation of nine OPPs, namely chlorpyrifos, chlorpyrifos-methyl, diazinon, dichlorvos, fenthion, malathion, phorate, pirimiphos-methyl and trichlorphon, in skimmed milk was investigated to clarify their susceptibility towards lactic acid bacteria (LAB) and yogurt starters. Skimmed milk was spiked with nine OPPs, inoculated with five strains of LAB and two commercial yogurt starters at 42 °C for 24 and 5 h respectively and subjected to quantitative OPP analysis by gas chromatography. Degradation kinetic constants of these OPPs were calculated based on a first-order reaction model. OPP dissipation in the milk was enhanced by the inoculated strains and starters, resulting in OPP concentrations decreasing by 7.0-64.6 and 7.4-19.2% respectively. Totally, the nine OPPs were more susceptible to Lactobacillus bulgaricus, as it enhanced their degradation rate constants by 18.3-133.3%. Higher phosphatase production of the assayed stains was observed to bring about greater OPP degradation in the milk. Both LAB and yogurt starters could enhance OPP dissipation in skimmed milk, with the nine OPPs studied having different susceptibilities towards them. Phosphatase was a key factor governing OPP dissipation. The LAB of higher phosphatase production have more potential to decrease OPPs in fermented foods. © 2014 Society of Chemical Industry.

  3. A portable liquid crystal-based polarized light system for the detection of organophosphorus nerve gas

    Science.gov (United States)

    He, Feng Jie; Liu, Hui Long; Chen, Long Cong; Xiong, Xing Liang

    2018-03-01

    Liquid crystal (LC)-based sensors have the advantageous properties of being fast, sensitive, and label-free, the results of which can be accessed directly only through the naked eye. However, the inherent disadvantages possessed by LC sensors, such as relying heavily on polarizing microscopes and the difficulty to quantify, have limited the possibility of field applications. Herein, we have addressed these issues by constructing a portable polarized detection system with constant temperature control. This system is mainly composed of four parts: the LC cell, the optics unit, the automatic temperature control unit, and the image processing unit. The LC cell was based on the ordering transitions of LCs in the presence of analytes. The optics unit based on the imaging principle of LCs was designed to substitute the polarizing microscope for the real-time observation. The image processing unit is expected to quantify the concentration of analytes. The results have shown that the presented system can detect dimethyl methyl phosphonate (a stimulant for organophosphorus nerve gas) within 25 s, and the limit of detection is about 10 ppb. In all, our portable system has potential in field applications.

  4. Determination of organophosphorus pesticides using molecularly imprinted polymer solid phase extraction

    International Nuclear Information System (INIS)

    Mohd Marsin Sanagi; Syairah Salleh; Wan Aini Wan Ibrahim

    2011-01-01

    Molecularly imprinted polymer solid phase extraction (MIP-SPE) method has been developed for the determination of organophosphorus pesticides (OPPs) in water samples. The MIP was prepared by thermo-polymerization method using methacrylic acid (MAA) as functional monomer, ethylene glycol dimethacrylate (EGDMA) as crosslinker, acetonitrile as porogenic solvent and quinalphos as the template molecule. The three OPPs (diazinon, quinalphos and chloropyrifos) were selected as target analytes as they are widely used in agriculture sector. Various parameters affecting the extraction efficiency of the imprinted polymers have been evaluated to optimize the selective preconcentration of OPPs from aqueous samples. The characteristics of the MIP-SPE method were validated by high performance liquid chromatography (HPLC). The accuracy and selectivity of the MIP-SPE process developed were verified using non-imprinted polymer solid phase extraction (NIP-SPE) and a commercial C 18 -SPE was used for comparison. The recoveries of the target analytes obtained using the MIPs as the solid phase sorbent ranged from 83% to 98% (RSDs 1.05 - 1.98 %; n=3) for water sample. The developed MIP-SPE method demonstrates that it could be applied for the determination of OPPs in water samples. (author)

  5. Competitive immunochromatographic assay for the detection of the organophosphorus pesticide chlorpyrifos

    Science.gov (United States)

    Kim, Young Ah; Lee, Eun-Hye; Kim, Kwang-Ok; Lee, Yong Tae; Hammock, Bruce D.; Lee, Hye-Sung

    2014-01-01

    An immunochromatographic assay (ICA) based on competitive antigen-coated format using colloidal gold as the label was developed for the detection of the organophosphorus insecticide chlorpyrifos. The ICA test strip consisted of a membrane with a detection zone, a sample pad and an absorbent pad. The membrane was separately coated with chlorpyrifos hapten-OVA conjugate (test line) and anti-mouse IgG (control line). Based on the fact that the competition is between the migrating analyte in the sample and the analyte hapten immobilized on the test strip for the binding sites of the antibody-colloidal gold (Ab-CG) conjugate migrating on the test strip, this study suggests that the relative migration speed between the two migrating substances is a critically important factor for the sensitive detection by competitive ICA. This criterion was utilized for the confirmation of appropriateness of a nitrocellulose (NC) membrane for chlorpyrifos ICA. The detection limit of the ICA for chlorpyrifos standard and chlorpyrifos spiked into agricultural samples were 10 and 50 ng mL−1, respectively. The assay time for the ICA test was less than 10 min, suitable for rapid on-site testing of chlorpyrifos. PMID:21504817

  6. Removal of actinides from nuclear fuel reprocessing waste solutions with bidentate organophosphorus extractants

    International Nuclear Information System (INIS)

    Schulz, W.W.; McIsaac, L.D.

    1975-08-01

    The neutral bidentate organophosphorus reagents DBDECMP (dibutyl-N,N-diethylcarbamylmethylenephosphonate) and its dihexyl analogue DHDECMP are candidate extractants for removal of actinides from certain acidic waste streams produced at the U. S. ERDA Hanford and Idaho Falls sites. Various chemical and physical properties including availability, cost, purification, alpha radiolysis, and aqueous phase solubility of DBDECMP and DHDECMP are reviewed. A conceptual flowsheet employing a 15 percent DBDECMP (or DHDECMP)--CCl 4 extractant for removal (and recovery) of Am and Pu from Hanford's Plutonium Reclamation Facility acid waste stream (CAW solution) was successfully demonstrated in laboratory-scale mixer-settler tests; this extraction scheme can be used to produce an actinide-free waste. A 30 percent DBDECMP-xylene flowsheet is being tested at the Idaho Falls site for removal of U, Np, Pu, and Am from Idaho Chemical Processing Plant first-cycle high-level raffinate to produce an actinide-free (less than 10 nCi alpha activity/gram) waste. (auth)

  7. Improvement of Some Biochemical Activities of Rats Treated with The Organophosphorus Insecticide Cytrolane Using Soyabean

    International Nuclear Information System (INIS)

    Abdel-Fattah, A.M.; Elmahdy, A.A.

    2005-01-01

    This Study aims to evaluate the role of soyabean diet in improvement of some biochemical activities of female rats received daily oral dose 0.89 mg/kg (1/10 LD 50 )of cytrolane as organophosphorus insecticide on some biochemical activities in female rats for ten consecutive days. Prior pesticide administration, female rats received soyabean at dose 58 g/kg body weight for 2 and 4 weeks. Under the effect of cytrolane administration, the results showed significant increase in serum triglycerides, total cholesterol, HDL-cholesterol and CPK mean levels. Total serum protein and progesterone levels were significantly decreased compared to the control. On the other hand, by the administration of soyabean prior cytrolane, it reduced considerably the changes produced by cytrolane on levels of serum cholesterol, triglyceride, HDL-cholesterol which decreased more or less compared to control, total protein level was within normal value. Also, serum progesterone concentration increased. Therefore, soyabean administration accelerated the normalization and improvement processes of the altered lipid profiles, protein and progesterone hormone

  8. Biosensors and their applications in detection of organophosphorus pesticides in the environment.

    Science.gov (United States)

    Hassani, Shokoufeh; Momtaz, Saeideh; Vakhshiteh, Faezeh; Maghsoudi, Armin Salek; Ganjali, Mohammad Reza; Norouzi, Parviz; Abdollahi, Mohammad

    2017-01-01

    This review discusses the past and recent advancements of biosensors focusing on detection of organophosphorus pesticides (OPs) due to their exceptional use during the last decades. Apart from agricultural benefits, OPs also impose adverse toxicological effects on animal and human population. Conventional approaches such as chromatographic techniques used for pesticide detection are associated with several limitations. A biosensor technology is unique due to the detection sensitivity, selectivity, remarkable performance capabilities, simplicity and on-site operation, fabrication and incorporation with nanomaterials. This study also provided specifications of the most OPs biosensors reported until today based on their transducer system. In addition, we highlighted the application of advanced complementary materials and analysis techniques in OPs detection systems. The availability of these new materials associated with new sensing techniques has led to introduction of easy-to-use analytical tools of high sensitivity and specificity in the design and construction of OPs biosensors. In this review, we elaborated the achievements in sensing systems concerning innovative nanomaterials and analytical techniques with emphasis on OPs.

  9. Degradation of Organophosphorus and Pyrethroid Insecticides in Beverages: Implications for Risk Assessment

    Directory of Open Access Journals (Sweden)

    Samantha A. Radford

    2018-02-01

    Full Text Available Since urinary insecticide metabolites are commonly used as biomarkers of exposure, it is important that we quantify whether insecticides degrade in food and beverages in order to better perform risk assessment. This study was designed to quantify degradation of organophosphorus and pyrethroid insecticides in beverages. Purified water, white grape juice, orange juice, and red wine were fortified with 500 ng/mL diazinon, malathion, chlorpyrifos, permethrin, cyfluthrin, cypermethrin, and deltamethrin, and aliquots were extracted several times over a 15-day storage period at 2.5 °C. Overall, statistically significant loss of at least one insecticide was observed in each matrix, and at least five out of seven insecticides demonstrated a statistically significant loss in all matrices except orange juice. An investigation of an alternative mechanism of insecticide loss—adsorption onto the glass surface of the storage jars—was carried out, which indicated that this mechanism of loss is insignificant. Results of this work suggest that insecticides degrade in these beverages, and this degradation may lead to pre-existing insecticide degradates in the beverages, suggesting that caution should be exercised when using urinary insecticide metabolites to assess exposure and risk.

  10. Gas chromatography with flame photometric detection of 31 organophosphorus pesticide residues in Alpinia oxyphylla dried fruits.

    Science.gov (United States)

    Zhao, Xiangsheng; Kong, Weijun; Wei, Jianhe; Yang, Meihua

    2014-11-01

    A simple, rapid and effective gas chromatography-flame photometric detection method was established for simultaneous multi-component determination of 31 organophosphorus pesticides (OPPs) residues in Alpinia oxyphylla, which is widely consumed as a traditional medicine and food in China. Sample preparation was completed in a single step without any clean-up procedure. All pesticides expressed good linear relationships between 0.004 and 1.0 μg/mL with correlation coefficients higher than 0.9973. The method gave satisfactory recoveries for most pesticides. The limits of detection varied from 1 to 10 ng/mL, and the limits of quantification (LOQs) were between 4 and 30 ng/mL. The proposed method was successfully applied to 55 commercial samples purchased from five different areas. Five pesticide residues were detected in four (7.27%) samples. The positive samples were confirmed by gas chromatography with tandem mass spectrometry (GC-MS/MS). Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Theoretical and experimental study of actinide complexes with monoamides and organophosphorus ligands in solution

    International Nuclear Information System (INIS)

    Ribokaite, Kristina

    2013-01-01

    Monoamides and organophosphate are of great interest for the nuclear fuel cycle. Such ligands can selectively extract actinides in liquid-liquid extraction processes. The structure of the extractant (its functional group and its alkyl substituents) has a predominant role in the selective separation of actinides. This thesis concerns the theoretical and experimental studies of model systems in the aim of better understanding of the effect on molecular structures of the complexes. Structures of actinides complexes formed with model ligands in simple media (water or methanol in the presence of nitrate ions) have been characterized. At first, the complexation of uranyl by monoamide and phosphine oxide was studied in water and methanol. Molecular Dynamics simulations and DFT calculations were used to quantify the stability of uranyl complexes with those ligands, and to determine their structural properties. The theoretical results were then compared with experimental results obtained by UV-visible, infrared, Raman and EXAFS on the same chemical systems. The results were used to highlight the greater stability of uranyl complexes with phosphine oxide and monoamides. Further spectroscopic measurements combined with molecular modeling were used to gain a better understanding of the coordination mode of nitrate ion around the uranyl in both water and methanol. Finally, DFT calculations were used to study the influence of the structure of the monoamide or organophosphorus ligand and their interaction with the actinides (IV, VI) including steric effects in the first coordination sphere. (author) [fr

  12. Pharmacological treatment of organophosphorus insecticide poisoning: the old and the (possible) new.

    Science.gov (United States)

    Eddleston, Michael; Chowdhury, Fazle Rabbi

    2016-03-01

    Despite being a major clinical and public health problem across the developing world, responsible for at least 5 million deaths over the last three decades, the clinical care of patients with organophosphorus (OP) insecticide poisoning has little improved over the last six decades. We are still using the same two antidotes - atropine and oximes - that first came into clinical use in the late 1950s. Clinical research in South Asia has shown how improved regimens of atropine can prevent deaths. However, we are still unsure about which patients are most likely to benefit from the use of oximes. Supplemental antidotes, such as magnesium, clonidine and sodium bicarbonate, have all been proposed and studied in small trials without production of definitive answers. Novel antidotes such as nicotinic receptor antagonists, beta-adrenergic agonists and lipid emulsions are being studied in large animal models and in pilot clinical trials. Hopefully, one or more of these affordable and already licensed antidotes will find their place in routine clinical care. However, the large number of chemically diverse OP insecticides, the varied poisoning they produce and their varied response to treatment might ultimately make it difficult to determine definitively whether these antidotes are truly effective. In addition, the toxicity of the varied solvents and surfactants formulated with the OP active ingredients complicates both treatment and studies. It is possible that the only effective way to reduce deaths from OP insecticide poisoning will be a steady reduction in their agricultural use worldwide. © 2015 The British Pharmacological Society.

  13. Effects of organophosphorus flame retardant TDCPP on normal human corneal epithelial cells: Implications for human health.

    Science.gov (United States)

    Xiang, Ping; Liu, Rong-Yan; Li, Chao; Gao, Peng; Cui, Xin-Yi; Ma, Lena Q

    2017-11-01

    Tris(1,3-dichloro-2-propyl) phosphate (TDCPP) is one of the most detected organophosphorus flame retardants (OPFRs) in the environment, especially in indoor dust. Continuous daily exposure to TDCPP-containing dust may adversely impact human cornea. However, its detrimental effects on human corneal epithelium are largely unknown. In this study, we investigated the cell apoptosis in normal human corneal epithelial cells (HCECs) after TDCPP exposure and elucidated the underlying molecular mechanisms. Our data indicated a dose-dependent decrease of cell viability after TDCPP exposure with LC 50 at 202 μg/mL. A concentration-dependent apoptotic sign was observed in HCECs after exposing to ≥2 μg/mL TDCPP. Endoplasmic reticulum stress induction was evidenced by up-regulation of its biomarker genes (ATF-4, CHOP, BiP, and XBP1). Furthermore, alternation of Bcl-2/Bax expression, mitochondrial membrane potential loss, cellular ATP content decrease, and caspase-3 and -9 activity increase were observed after exposing to 2 or 20 μg/mL TDCPP. Taken together, the data implicated the involvement of endoplasmic reticulum stress in TDCPP-induced HCEC apoptosis, probably mediated by mitochondrial apoptotic pathway. Our findings showed TDCPP exposure induced toxicity to human cornea. Due to TDCPP's presence at high levels in indoor dust, further study is warranted to evaluate its health risk on human corneas. Published by Elsevier Ltd.

  14. Organophosphorus pesticide exposure in agriculture: effects of temperature, ultraviolet light and abrasion on PVC gloves

    Science.gov (United States)

    ISMAIL, Ismaniza; GASKIN, Sharyn; PISANIELLO, Dino; EDWARDS, John W.

    2017-01-01

    Elbow length PVC gloves are often recommended for protection against organophosphorus pesticide (OP) exposure in agriculture. However, performance may be reduced due to high temperature, UV exposure and abrasion. We sought to assess these impacts for two OPs under normal use and reasonable worst-case scenarios. Glove permeation tests were conducted using ASTM cells with two PVC glove brands at 23°C and 45°C for up to 8 h. Technical grade dichlorvos and formulated diazinon were used undiluted and at application strength. Breakthough of undiluted dichlorvos occurred at both 23°C and 45°C, but only at 45°C for application strength. Breakthrough of diazinon was not achieved, except when undiluted at 45°C. UV-exposed and abraded gloves showed reduced performance, with the effect being approximately two-fold for dichlorvos. Only small differences were noted between glove brands. Extra precautions should be taken when handling concentrated OPs at high temperature, or when using abraded or sunlight-exposed gloves. PMID:29199264

  15. Effect of diluents on the extraction of actinides and nitric acid by bidentate organophosphorus compounds

    International Nuclear Information System (INIS)

    Rozen, A.M.

    1986-01-01

    The effect of dilutents on extraction by bidentate organophosphorus compounds (diphosphine dioxides, carbamoyl phosphonates, and phosphine oxides) was studied. Figures show the effect of dilutents on the extraction of americium by TOPO and by carbamoylmethylene phosphonate, and the effect of dilutents on the extraction of nitric acid and americium by carbamoylphosphine oxide. Also shown is the effect of dilutents on the extraction of americium by diphenyldioctyl methylenediphosphine dioxide, and the effect of dilutents on the extraction of americium by tetraphenylmethylenediphosphine dioxide. It was concluded that when TBP is added the distribution coefficient of Am increases but the effect of TBP may not be represented by the usual power relationship between the distribution coefficient and the TBP concentration, which would be expected if TBP was found to be very strong but for dilution by DCE it was relatively weak. The observed facts can be explained if it is assumed that TBP reacts with the bridging protons in the complex, which are free for dilution by benzene and are partially occupied when dichlorethane is used

  16. Organophosphorus esters in the oceans and possible relation with ocean gyres

    International Nuclear Information System (INIS)

    Cheng, Wenhan; Xie, Zhouqing; Blais, Jules M.; Zhang, Pengfei; Li, Ming; Yang, Chengyun; Huang, Wen; Ding, Rui; Sun, Liguang

    2013-01-01

    Four organophosphorus esters (OPEs) were detected in aerosol samples collected in the West Pacific, the Indian Ocean and the Southern Ocean from 2009 to 2010, suggesting their circumpolar and global distribution. In general, the highest concentrations were detected near populated regions in China, Australia and New Zealand. OPE concentrations in the Southern Ocean were about two orders of magnitude lower than those near major continents. Additionally, relatively high OPE concentrations were detected at the Antarctic Peninsula, where several scientific survey stations are located. The four OPEs investigated here are significantly correlated with each other, suggesting they may derive from the same source. In the circumpolar transect, OPE concentrations were associated with ocean gyres in the open ocean. Their concentrations were positively related with average vorticity in the sampling area suggesting that a major source of OPEs may be found in ocean gyres where plastic debris is known to accumulate. -- Highlights: •We provide OPE concentrations in aerosols in a circumpolar expedition. •We find strong anthropogenic source of OPE pollution. •We suggest potential relationship between ocean gyres and OPE pollution. -- Our work provides a circumpolar investigation on OPEs in the Southern Ocean and we suggest a possibility that ocean currents and gyres may act as important roles in global transport of OPEs

  17. Computational Enzymology and Organophosphorus Degrading Enzymes: Promising Approaches Toward Remediation Technologies of Warfare Agents and Pesticides.

    Science.gov (United States)

    Ramalho, Teodorico C; de Castro, Alexandre A; Silva, Daniela R; Silva, Maria Cristina; Franca, Tanos C C; Bennion, Brian J; Kuca, Kamil

    2016-01-01

    The re-emergence of chemical weapons as a global threat in hands of terrorist groups, together with an increasing number of pesticides intoxications and environmental contaminations worldwide, has called the attention of the scientific community for the need of improvement in the technologies for detoxification of organophosphorus (OP) compounds. A compelling strategy is the use of bioremediation by enzymes that are able to hydrolyze these molecules to harmless chemical species. Several enzymes have been studied and engineered for this purpose. However, their mechanisms of action are not well understood. Theoretical investigations may help elucidate important aspects of these mechanisms and help in the development of more efficient bio-remediators. In this review, we point out the major contributions of computational methodologies applied to enzyme based detoxification of OPs. Furthermore, we highlight the use of PTE, PON, DFP, and BuChE as enzymes used in OP detoxification process and how computational tools such as molecular docking, molecular dynamics simulations and combined quantum mechanical/molecular mechanics have and will continue to contribute to this very important area of research.

  18. Toxicology of organophosphorus compounds in view of an increasing terrorist threat.

    Science.gov (United States)

    Worek, Franz; Wille, Timo; Koller, Marianne; Thiermann, Horst

    2016-09-01

    The implementation of the Chemical Weapon Convention (CWC), prohibiting the development, production, storage and use of chemical weapons by 192 nations and the ban of highly toxic OP pesticides, especially class I pesticides according to the WHO classification, by many countries constitutes a great success of the international community. However, the increased interest of terrorist groups in toxic chemicals and chemical warfare agents presents new challenges to our societies. Almost seven decades of research on organophosphorus compound (OP) toxicology was mainly focused on a small number of OP nerve agents despite the fact that a huge number of OP analogues, many of these agents having comparable toxicity to classical nerve agents, were synthesized and published. Only limited physicochemical, toxicological and medical information on nerve agent analogues is available in the open literature. This implies potential gaps of our capabilities to detect, to decontaminate and to treat patients if nerve agent analogues are disseminated and may result in inadequate effectiveness of newly developed countermeasures. In summary, our societies may face new, up to now disregarded, threats by toxic OP which calls for increased awareness and appropriate preparedness of military and civilian CBRN defense, a broader approach for new physical and medical countermeasures and an integrated system of effective detection, decontamination, physical protection and treatment.

  19. Vitamin K3 (menadione) redox cycling inhibits cytochrome P450-mediated metabolism and inhibits parathion intoxication.

    Science.gov (United States)

    Jan, Yi-Hua; Richardson, Jason R; Baker, Angela A; Mishin, Vladimir; Heck, Diane E; Laskin, Debra L; Laskin, Jeffrey D

    2015-10-01

    Parathion, a widely used organophosphate insecticide, is considered a high priority chemical threat. Parathion toxicity is dependent on its metabolism by the cytochrome P450 system to paraoxon (diethyl 4-nitrophenyl phosphate), a cytotoxic metabolite. As an effective inhibitor of cholinesterases, paraoxon causes the accumulation of acetylcholine in synapses and overstimulation of nicotinic and muscarinic cholinergic receptors, leading to characteristic signs of organophosphate poisoning. Inhibition of parathion metabolism to paraoxon represents a potential approach to counter parathion toxicity. Herein, we demonstrate that menadione (methyl-1,4-naphthoquinone, vitamin K3) is a potent inhibitor of cytochrome P450-mediated metabolism of parathion. Menadione is active in redox cycling, a reaction mediated by NADPH-cytochrome P450 reductase that preferentially uses electrons from NADPH at the expense of their supply to the P450s. Using human recombinant CYP 1A2, 2B6, 3A4 and human liver microsomes, menadione was found to inhibit the formation of paraoxon from parathion. Administration of menadione bisulfite (40mg/kg, ip) to rats also reduced parathion-induced inhibition of brain cholinesterase activity, as well as parathion-induced tremors and the progression of other signs and symptoms of parathion poisoning. These data suggest that redox cycling compounds, such as menadione, have the potential to effectively mitigate the toxicity of organophosphorus pesticides including parathion which require cytochrome P450-mediated activation. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Effects of the organophosphorus pesticide Folisuper 600 (methyl parathion on the heart function of bullfrog tadpoles, Lithobates catesbeianus (Shaw, 1802

    Directory of Open Access Journals (Sweden)

    M. J. Costa

    Full Text Available Abstract The aim of this work was to evaluate whether the heart function of bullfrog tadpoles (25 Gosner stage is affected by their acute exposure (48 h to a sub-lethal concentration (10 µg.L–1 of the active principle of the organophosphorus pesticide Folisuper 600R (methyl parathion - MP. Our results demonstrated that MP causes not only a reduction in tadpoles’ cardiac ventricular mass, resulting in a marked reduction in their cardiac twitch force, but also impairs their swimming performance, irrespective of increasing their heart rate. Together, these findings indicate that low and realistic concentration of MP have a negative impact on tadpoles’ performance, jeopardizing their survival.

  1. Vitamin K3 (menadione) redox cycling inhibits cytochrome P450-mediated metabolism and inhibits parathion intoxication

    Energy Technology Data Exchange (ETDEWEB)

    Jan, Yi-Hua [Department of Environmental and Occupational Medicine, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ (United States); Richardson, Jason R., E-mail: jricha3@eohsi.rutgers.edu [Department of Environmental and Occupational Medicine, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ (United States); Baker, Angela A. [Department of Environmental and Occupational Medicine, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ (United States); Mishin, Vladimir [Department of Pharmacology and Toxicology, Rutgers University, Piscataway, NJ (United States); Heck, Diane E. [Department of Environmental Health Science, New York Medical College, Valhalla, NY (United States); Laskin, Debra L. [Department of Pharmacology and Toxicology, Rutgers University, Piscataway, NJ (United States); Laskin, Jeffrey D., E-mail: jlaskin@eohsi.rutgers.edu [Department of Environmental and Occupational Medicine, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ (United States)

    2015-10-01

    Parathion, a widely used organophosphate insecticide, is considered a high priority chemical threat. Parathion toxicity is dependent on its metabolism by the cytochrome P450 system to paraoxon (diethyl 4-nitrophenyl phosphate), a cytotoxic metabolite. As an effective inhibitor of cholinesterases, paraoxon causes the accumulation of acetylcholine in synapses and overstimulation of nicotinic and muscarinic cholinergic receptors, leading to characteristic signs of organophosphate poisoning. Inhibition of parathion metabolism to paraoxon represents a potential approach to counter parathion toxicity. Herein, we demonstrate that menadione (methyl-1,4-naphthoquinone, vitamin K3) is a potent inhibitor of cytochrome P450-mediated metabolism of parathion. Menadione is active in redox cycling, a reaction mediated by NADPH-cytochrome P450 reductase that preferentially uses electrons from NADPH at the expense of their supply to the P450s. Using human recombinant CYP 1A2, 2B6, 3A4 and human liver microsomes, menadione was found to inhibit the formation of paraoxon from parathion. Administration of menadione bisulfite (40 mg/kg, ip) to rats also reduced parathion-induced inhibition of brain cholinesterase activity, as well as parathion-induced tremors and the progression of other signs and symptoms of parathion poisoning. These data suggest that redox cycling compounds, such as menadione, have the potential to effectively mitigate the toxicity of organophosphorus pesticides including parathion which require cytochrome P450-mediated activation. - Highlights: • Menadione redox cycles with cytochrome P450 reductase and generates reactive oxygen species. • Redox cycling inhibits cytochrome P450-mediated parathion metabolism. • Short term administration of menadione inhibits parathion toxicity by inhibiting paraoxon formation.

  2. Vitamin K3 (menadione) redox cycling inhibits cytochrome P450-mediated metabolism and inhibits parathion intoxication

    International Nuclear Information System (INIS)

    Jan, Yi-Hua; Richardson, Jason R.; Baker, Angela A.; Mishin, Vladimir; Heck, Diane E.; Laskin, Debra L.; Laskin, Jeffrey D.

    2015-01-01

    Parathion, a widely used organophosphate insecticide, is considered a high priority chemical threat. Parathion toxicity is dependent on its metabolism by the cytochrome P450 system to paraoxon (diethyl 4-nitrophenyl phosphate), a cytotoxic metabolite. As an effective inhibitor of cholinesterases, paraoxon causes the accumulation of acetylcholine in synapses and overstimulation of nicotinic and muscarinic cholinergic receptors, leading to characteristic signs of organophosphate poisoning. Inhibition of parathion metabolism to paraoxon represents a potential approach to counter parathion toxicity. Herein, we demonstrate that menadione (methyl-1,4-naphthoquinone, vitamin K3) is a potent inhibitor of cytochrome P450-mediated metabolism of parathion. Menadione is active in redox cycling, a reaction mediated by NADPH-cytochrome P450 reductase that preferentially uses electrons from NADPH at the expense of their supply to the P450s. Using human recombinant CYP 1A2, 2B6, 3A4 and human liver microsomes, menadione was found to inhibit the formation of paraoxon from parathion. Administration of menadione bisulfite (40 mg/kg, ip) to rats also reduced parathion-induced inhibition of brain cholinesterase activity, as well as parathion-induced tremors and the progression of other signs and symptoms of parathion poisoning. These data suggest that redox cycling compounds, such as menadione, have the potential to effectively mitigate the toxicity of organophosphorus pesticides including parathion which require cytochrome P450-mediated activation. - Highlights: • Menadione redox cycles with cytochrome P450 reductase and generates reactive oxygen species. • Redox cycling inhibits cytochrome P450-mediated parathion metabolism. • Short term administration of menadione inhibits parathion toxicity by inhibiting paraoxon formation.

  3. Phytase production by Aspergillus niger NCIM 563 for a novel application to degrade organophosphorus pesticides.

    Science.gov (United States)

    Shah, Parin C; Kumar, V Ravi; Dastager, Syed G; Khire, Jayant M

    2017-12-01

    The production of phytase using Aspergillus niger NCIM 563 under submerged fermentation conditions was studied using protein rich chickpea flour as substrate. Employing a hybrid statistical media optimization strategy of Plackett-Burman and Box-Behnken experimental designs in shake-flasks gave an increased phytase activity from an initial 66 IU/mL in 216 h to 160 IU/mL in a reduced time of 132 h. Productivity, thus increased by 3.97 times from 7.3 to 29 IU/mL/day. Using the optimized media, the production was successfully scaled-up further and improved up to 164 IU/mL in 96 h by studies carried out employing 2 and 10-L fermenters. The enzyme supernatant was recovered using centrifugal separation of biomass and the stability of the produced phytase was tested for animal feed applications under gastric conditions. In vitro degradation studies of water soluble monocrotophos, methyl parathion and water insoluble chlorpyrifos, pesticides used extensively in agriculture was carried out. It was observed by HPLC analysis that phytase could degrade 72% of chlorpyrifos at pH 7.0, 35 °C. Comparable results were obtained with monocrotophos and methyl parathion. With chlorpyrifos at higher temperature 50 °C as much as 91% degradation could be obtained. The degradation of chlorpyrifos was further validated by spraying phytase on harvested green chilli (Capsicum annuum L) under normal conditions of pH 7.0, 35 °C and the degradation products obtained analyzed by LCMS. Thus, the present study brings out a potentially novel application of phytase for biodegradation of organophosphorus pesticides.

  4. Determination of Organophosphorus Pesticides in Soil by Dispersive Liquid–Liquid Microextraction and Gas Chromatography

    Science.gov (United States)

    Yang, Zhonghua; Liu, Yu; Liu, Donghui; Zhou, Zhiqiang

    2012-01-01

    In this article, a rapid and sensitive sample pretreatment technique for the determination of organophosphorus pesticides (OPPs) in soil samples is developed by using dispersive liquid–liquid microextraction (DLLME) combined with gas chromatography–flame photometric detection. Experimental conditions, including the kind of extraction and disperser solvent and their volumes, the extraction time, and the salt addition, are investigated, and the following experiment factors are used: 20 µL chlorobenzene as the extraction solvent; 1.0 mL acetonitrile as the disperser solvent; no addition of salt; and an extraction time of 1 min. Under the optimum conditions, the linearities for the three target OPPs (ethoprophos, chlorpyriphos, and profenofos) are obtained by five points in the concentration range of 2.5–1500 µg/kg, and three replicates are used for each point. Correlation coefficients vary from 0.9987 to 0.9997. The repeatability is tested by spiking soil samples at a concentration level of 5.0 µg/kg. The relative standard deviation (n = 3) varied between 2.0% and 6.6%. The limits of detection, based on a signal-to-noise ratio (S/N) of 3, range from 200 to 500 pg/g. This method is applied to the analysis of the spiked samples S1, S2, and S3, which are collected from the China Agriculture University's orchard, lawn, and garden, respectively. The recoveries for each target analyte are in the range between 87.9% and 108.0%, 87.4% and 108.0%, and 86.7% and 107.2%, respectively. PMID:22291051

  5. Zirconium(IV) functionalized magnetic nanocomposites for extraction of organophosphorus pesticides from environmental water samples.

    Science.gov (United States)

    Jiang, Li; Huang, Tengjun; Feng, Shun; Wang, Jide

    2016-07-22

    The widespread use of organophosphate pesticides (OPPs) in agriculture leads to residue accumulation in the environment which is dangerous to human health and disrupts the ecological balance. In this work, one nanocomposite immobilized zirconium (Zr, IV) was prepared and used as the affinity probes to quickly and selectively extract organophosphorus pesticides (OPPs) from water samples. The Fe3O4-ethylenediamine tetraacetic acid (EDTA)@Zr(IV) nanocomposites (NPs) were prepared by simply mixing Zr(IV) ions with Fe3O4-EDTA NPs synthesized by one-pot chemical co-precipitation method. The immobilized Zr(IV) ions were further utilized to capture OPPs based on their high affinity for the phosphate moiety in OPPs. Coupled with GC-MS, four OPPs were used as models to demonstrate the feasibility of this approach. Under the optimum conditions, the limits of detection for target OPPs were in the range of 0.10-10.30ngmL(-1) with relative standard deviations (RSDs) of 0.61-4.40% (n=3), respectively. The linear ranges were over three orders of magnitudes (correlation coefficients, R(2)>0.9995). The Fe3O4-EDTA@Zr(IV) NPs were successfully applied to extract OPPs samples with recoveries of 86.95-112.60% and RSDs of 1.20-10.42% (n=3) from two spiked real water. By the proposed method, the matrix interference could be effectively eliminated. We hope our finding can provide a promising alternative for the fast extraction of OPPs from complex real samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Modulatory Effect Of Olive Oil On Toxicity Induced By Organophosphorus Pesticides In Male Rat

    International Nuclear Information System (INIS)

    AFIFI, E.A.A.; ALI, S.E.

    2009-01-01

    The present study was carried out to investigate the modulatory effect of olive oil (5 ml/kg b.wt.) against the toxicological effects of repeated daily oral administration of the organophosphorus pesticides malaphos (137.5 mg/kg), mephosfolan (0.89 mg/kg) and phosfolan (1.0 mg/kg) for one, two and four weeks on certain biochemical parameters such as serum albumin, globulin and A/G ratio, low density lipoprotein-cholesterol (LDL-cholesterol), high density lipoprotein-cholesterol (HDL-cholesterol), total cholesterol, total protein, gamma glutamyl transferase ( GT) and plasma triglycerides. In addition, modulation of blood urea, creatinine and uric acid were observed through all the experimental intervals. Also, the serum concentration of triiodothyronine (T 3 ), thyroxine (T 4 ) and thyroid stimulating hormone (TSH) were determined.The data obtained revealed significant decrease in serum total protein, albumin, globulin and HDL-cholesterol while significant increase in serum albumin to globulin ratio (A/G), triglycerides, creatinine, urea, uric acid, LDL-cholesterol, total cholesterol and GT in all treated groups was observed. On the other hand, the data recorded imbalance in thyroid function as a result of pesticides treatments, which donated that each of the three pesticides increased TSH secretion, while malaphos caused significant decrease in both T 3 and T 4 levels, mephosfolan increased T 4 and decreased T 3 levels, whereas phosfolan pesticide decreased T 4 and increased T 3 levels after one, two and four weeks post-treatment.Administration of olive oil during treatment with malaphos, mephosfolan and phosfolan pesticides attenuates to a great extent the destructive effects of pesticides on the assayed parameters, this effect is attributed to the beneficial properties whom olive oil possess as anti-oxidative potential that may act to protect the body organs against the pesticides toxicity and also due to the amelioration of oxidative stress of free radicals.

  7. Evaluation of the organophosphorus hydrolase enzyme activity in creams and investigation of its stability

    Directory of Open Access Journals (Sweden)

    Mariye Rajaie

    2016-06-01

    Full Text Available The main purpose of this project is investigation of the organophosphorus hydrolase (OPH enzyme activity in water in oil (w/o and oil in water (o/w creams and investigation of the OPH enzyme stability in formulated creams. OPH enzyme was extracted and purified from strain flavobacterium. The w/o and o/w creams were prepared using different formulations. In order to achieve an emulsion with maximum stability, appropriate percentage of the cream components was selected by studying different formulations and the physical and chemical stability of the produced cream were considered. 5Uenzyme/90gcream enzyme was used for each formulation. To measure the enzyme activity in creams, extraction method was used and enzyme activity was determined based on parathion hydrolysis. The thermal stability of OPH in both types of w/o and o/w creams was studied at 4 and 30  °C for various time periods. The average enzyme activity was about 0.0065 U/gcream and 0.018 U/gcream for w/o and o/w creams respectivly. According to the results, the relative activity at 4 °C was reduced to 50% after 26 and 45 days in w/o and o/w creams, respectivly. The results showed that the OPH enzyme activity in o/w cream was 2.6 times more than that of w/o cream, because of the higher hydrophobicity of o/w cream compared to w/o. The OPH enzyme stability in o/w cream was greater in comparison to w/o cream. The OPH enzyme was active for nearly 2 months on o/w creams at 4 °C .

  8. Organophosphorus pollutants (OPP) in aquatic environment at Damietta Governorate, Egypt: implications for monitoring and biomarker responses.

    Science.gov (United States)

    Abdel-Halim, K Y; Salama, A K; El-Khateeb, E N; Bakry, N M

    2006-06-01

    The study was carried out from spring 1999 to spring 2001 to monitor the residue levels of organophosphorus pollutants (OPP) in aquatic environment of the drainage canal surrounding a pesticide factory at Damietta Governorate. Water, sediment, and fish samples were collected at six different seasonal periods. OPPs were analyzed by GLC and confirmed using GC-MS. Chlorpyrifos, chlorpyrifos-methyl, malathion, diazinon, pirimiphos-methyl and profenofos were detected in most samples. Chlorpyrifos was dominant in all water and sediment samples. It was ranged from 24.5 to 303.8 and 0.9 to 303.8 ppb in water and sediment samples, respectively. Diazinon level was slightly similar to chlorpyrifos in fish samples. Data based on the grand total concentration of OPP showed that the most polluted samples were collected either at spring 1999 or autumn 2000. They were 675.5 and 303.8 ppb in water samples and 43.0 and 52.2 ppb in fish collected at spring 1999 and autumn 2000, respectively. The obtained results are in parallel to that found in case of cholinesterase activity where the activity of both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) was declined at these seasonal period. The activity levels of AChE and BuChE were found to be 77.18% and 59.67% of control at spring 1999 and 78.62% and 85.80% of control, at autumn 2000, respectively. Thus, AChE and BuChE could be used as biomarkers for tracing and biomonitoring OPP pollution.

  9. Synthesis, Biological Evaluation, and Docking Studies of Novel Bisquaternary Aldoxime Reactivators on Acetylcholinesterase and Butyrylcholinesterase Inhibited by Paraoxon

    Directory of Open Access Journals (Sweden)

    Kamil Kuca

    2018-05-01

    Full Text Available Nerve agents and oxon forms of organophosphorus pesticides act as strong irreversible inhibitors of two cholinesterases in the human body: acetylcholinesterase (AChE; EC 3.1.1.7 and butyrylcholinesterase (BChE; EC 3.1.1.8, and are therefore highly toxic compounds. For the recovery of inhibited AChE, antidotes from the group of pyridinium or bispyridinium aldoxime reactivators (pralidoxime, obidoxime, HI-6 are used in combination with anticholinergics and anticonvulsives. Therapeutic efficacy of reactivators (called “oximes” depends on their chemical structure and also the type of organophosphorus inhibitor. Three novel oximes (K131, K142, K153 with an oxime group in position four of the pyridinium ring were designed and then tested for their potency to reactivate human (Homo sapiens sapiens AChE (HssACHE and BChE (HssBChE inhibited by the pesticide paraoxon (diethyl 4-nitrophenyl phosphate. According to the obtained results, none of the prepared oximes were able to satisfactorily reactivate paraoxon-inhibited cholinesterases. On the contrary, extraordinary activity of obidoxime in the case of paraoxon-inhibited HssAChE reactivation was confirmed. Additional docking studies pointed to possible explanations for these results.

  10. Occurrence of Organophosphorus Flame Retardants and Plasticizers (PFRs) in Belgian Foodstuffs and Estimation of the Dietary Exposure of the Adult Population.

    Science.gov (United States)

    Poma, Giulia; Sales, Carlos; Bruyland, Bram; Christia, Christina; Goscinny, Séverine; Van Loco, Joris; Covaci, Adrian

    2018-02-20

    The occurrence of 14 organophosphorus flame retardants and plasticizers (PFRs) was investigated in 165 composite food samples purchased from the Belgian market and divided into 14 food categories, including fish, crustaceans, mussels, meat, milk, cheese, dessert, food for infants, fats and oils, grains, eggs, potatoes and derived products, other food (stocks), and vegetables. Seven PFRs [namely, tri-n-butyl phosphate (TnBP), tris(2-chloroethyl) phosphate (TCEP), tris(1-chloro-2-propyl) phosphate (TCIPP), tris(1,3-dichloro-2-propyl) phosphate (TDCIPP), triphenyl phosphate (TPHP), 2-ethylhexyldiphenyl phosphate (EHDPHP), and tris(2-ethylhexyl) phosphate (TEHP)] were detected at concentrations above quantification limits. Fats and oils were the most contaminated category, with a total PFR concentration of 84.4 ng/g of wet weight (ww), followed by grains (36.9 ng/g of ww) and cheese (20.1 ng/g of ww). Our results support the hypothesis that PFR contamination may occur during industrial processing and manipulation of food products (e.g., packaging, canning, drying, etc.). Considering the daily average intake of food for the modal adult Belgian (15-64 years of age), the dietary exposure to sum PFRs was estimated to be ≤7500 ± 1550 ng/day [103 ± 21 ng/kg of body weight (bw)/day]. For individual PFRs, TPHP contributed on average 3400 ng/day (46.6 ng/kg of bw/day), TCIPP 1350 ng/day (18.5 ng/kg of bw/day), and EHDPHP 1090 ng/day (15 ng/kg of bw/day), values that were lower than their corresponding health-based reference doses. The mean dietary exposure mainly originated from grains (39%), followed by fats and oils (21%) and dairy products (20%). No significant differences between the intakes of adult men and women were observed.

  11. Dust Measurement of Two Organophosphorus Flame Retardants, Resorcinol Bis(diphenylphosphate) (RBDPP) and Bisphenol A Bis(diphenylphosphate) (BPA-BDPP), Used as Alternatives for BDE-209

    NARCIS (Netherlands)

    Brandsma, S.H.; Sellström, U.; de Wit, C.A.; de Boer, J.; Leonards, P.E.G.

    2013-01-01

    Resorcinol bis(diphenylphosphate) (RBDPP) and bisphenol A bis(diphenylphosphate) (BPA-BDPP) are two halogen-free organophosphorus flame retardant (PFRs) that are used as an alternative for the decabromodiphenyl ether (Deca-BDE) technical mixture in TV/flatscreen housing and other electronic consumer

  12. Monitoring of organochlorine and organophosphorus pesticide residues in water during different seasons of Tighra reservoir Gwalior, Madhya Pradesh, India.

    Science.gov (United States)

    Mamta; Rao, R J; Wani, Khursheed Ahmad

    2015-11-01

    Analysis of pesticides during different seasons for pesticidal contamination in water samples of Tighra reservoir was carried out on gas chromatograph-electron capture detector with capillary columns following multiresidual analytical technique. Organochlorine pesticides, viz., hexachlorobenzene (HCB), alpha-benzene hexachloride (BHC), beta-BHC, γ-BHC, heptachlor, aldrin, alpha-endosulfan, beta-endosulfan, p,p-DDE, dieldrin, o,p-dichlorodiphenyldichloroethane (DDD), p,p-DDD, p,p-dichlorodiphenyltrichloroethane (DDT), and endrin, and organophosphorus pesticides, viz., choloropyrifos, methyl parathion, diazion, dicholorovos, ethion, malathion, and parathion, were detected in water samples during different seasons. However, the pesticide concentration varied during different seasons at different sites. The prominent reason of contamination is the use of pesticides (both organochlorine and organophosphorus) in the agricultural fields near Tighra reservoir. On the basis of our observations, more extensive monitoring studies need to be carried out, covering all wetlands of Madhya Pradesh to enforce the policies for the restricted application of pesticides in agricultural fields adjacent to wetlands.

  13. Synthesis of organophosphorus modified nanoparticles and their reinforcements on the fire safety and mechanical properties of polyurea

    Energy Technology Data Exchange (ETDEWEB)

    Qian, Xiaodong [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026 (China); USTC-CityU Joint Advanced Research Centre, Suzhou Key Laboratory of Urban Public Safety, Suzhou Institute for Advanced Study, University of Science and Technology of China, 166 Ren’ai Road Suzhou, Jiangsu 215123 (China); Song, Lei, E-mail: leisong@ustc.edu.cn [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026 (China); Wang, Bibo [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026 (China); Hu, Yuan, E-mail: yuanhu@ustc.edu.cn [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026 (China); USTC-CityU Joint Advanced Research Centre, Suzhou Key Laboratory of Urban Public Safety, Suzhou Institute for Advanced Study, University of Science and Technology of China, 166 Ren’ai Road Suzhou, Jiangsu 215123 (China); Yuen, Richard K.K., E-mail: Richard.Yuen@cityu.edu.hk [USTC-CityU Joint Advanced Research Centre, Suzhou Key Laboratory of Urban Public Safety, Suzhou Institute for Advanced Study, University of Science and Technology of China, 166 Ren’ai Road Suzhou, Jiangsu 215123 (China); Department of Building and Construction, City University of Hong Kong, Tat Chee Avenue Kowloon (Hong Kong)

    2013-05-15

    Novel organophosphorus modified nanoparticles (FRs-nanoparticles) were synthesized by the hydrolysis and condensation of both 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide modified vinyl trimethoxy silane (DOPO-VTS) and 3-triethoxysilylpropylamine. FRs-nanoparticles were incorporated into the polyurea matrix in different ratios via in situ polymerization, resulting in the formation of organic/inorganic nanocomposites. The nanocomposites were characterized by thermogravimetric analysis (TGA), real-time fourier transform infrared spectra (RTIR), microscale combustion calorimeter (MCC) and tensile testing machine. The TGA results revealed that FRs-nanoparticles could slightly catalyze the thermal degradation of the nanocomposites in nitrogen atmosphere, but significantly improve the thermal stability of the nanocomposites in air atmosphere. The T{sub 0.5} (50wt.% weight loss) of the nanocomposites was delayed by 32 °C in air atmosphere. Moreover, the char yield increased from 2.3wt.% to 8.9 wt.% at 550 °C when the loadings of FRs-nanoparticles was 10wt.%, indicating the catalyzing charring effect of FRs-nanoparticles. The MCC results revealed that all the nanocomposites exhibited much lower flammability compared with virgin polyurea. Furthermore, the tensile test indicated that the FRs-nanoparticles could also improve the mechanical properties of polyurea. - Highlights: ► Novel organophosphorus modified nanoparticles (FRs-nanoparticles) were synthesized. ► FRs-nanoparticles were incorporated into the polyurea. ► Both the thermal stability and mechanical properties of polyurea were improved.

  14. Detection of Organophosphorus Pesticides in Wheat by Ionic Liquid-Based Dispersive Liquid-Liquid Microextraction Combined with HPLC

    Directory of Open Access Journals (Sweden)

    Wei Liu

    2018-01-01

    Full Text Available Food safety issues closely related to human health have always received widespread attention from the world society. As a basic food source, wheat is the fundamental support of human survival; therefore, the detection of pesticide residues in wheat is very necessary. In this work, the ultrasonic-assisted ionic liquid-dispersive liquid-liquid microextraction (DLLME method was firstly proposed, and the extraction and analysis of three organophosphorus pesticides were carried out by combining high-performance liquid chromatography (HPLC. The extraction efficiencies of three ionic liquids with bis(trifluoromethylsulfonylimide (Tf2N anion were compared by extracting organophosphorus in wheat samples. It was found that the use of 1-octyl-3-methylimidazolium bis(trifluoromethylsulfonylimide ([OMIM][Tf2N] had both high enrichment efficiency and appropriate extraction recovery. Finally, the method was used for the determination of three wheat samples, and the recoveries of them were 74.8–112.5%, 71.8–104.5%, and 83.8–115.5%, respectively. The results show that the method proposed is simple, fast, and efficient, which can be applied to the extraction of organic matters in wheat samples.

  15. Synthesis of organophosphorus modified nanoparticles and their reinforcements on the fire safety and mechanical properties of polyurea

    International Nuclear Information System (INIS)

    Qian, Xiaodong; Song, Lei; Wang, Bibo; Hu, Yuan; Yuen, Richard K.K.

    2013-01-01

    Novel organophosphorus modified nanoparticles (FRs-nanoparticles) were synthesized by the hydrolysis and condensation of both 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide modified vinyl trimethoxy silane (DOPO-VTS) and 3-triethoxysilylpropylamine. FRs-nanoparticles were incorporated into the polyurea matrix in different ratios via in situ polymerization, resulting in the formation of organic/inorganic nanocomposites. The nanocomposites were characterized by thermogravimetric analysis (TGA), real-time fourier transform infrared spectra (RTIR), microscale combustion calorimeter (MCC) and tensile testing machine. The TGA results revealed that FRs-nanoparticles could slightly catalyze the thermal degradation of the nanocomposites in nitrogen atmosphere, but significantly improve the thermal stability of the nanocomposites in air atmosphere. The T 0.5 (50wt.% weight loss) of the nanocomposites was delayed by 32 °C in air atmosphere. Moreover, the char yield increased from 2.3wt.% to 8.9 wt.% at 550 °C when the loadings of FRs-nanoparticles was 10wt.%, indicating the catalyzing charring effect of FRs-nanoparticles. The MCC results revealed that all the nanocomposites exhibited much lower flammability compared with virgin polyurea. Furthermore, the tensile test indicated that the FRs-nanoparticles could also improve the mechanical properties of polyurea. - Highlights: ► Novel organophosphorus modified nanoparticles (FRs-nanoparticles) were synthesized. ► FRs-nanoparticles were incorporated into the polyurea. ► Both the thermal stability and mechanical properties of polyurea were improved

  16. Astragalin, a Flavonoid from Morus alba (Mulberry Increases Endogenous Estrogen and Progesterone by Inhibiting Ovarian Granulosa Cell Apoptosis in an Aged Rat Model of Menopause

    Directory of Open Access Journals (Sweden)

    Min Wei

    2016-05-01

    Full Text Available Background: To determine the mechanism by which the flavonoid glycoside astragalin (AST reduces ovarian failure in an aged rat model of menopause. Methods: The in vivo effect of AST on granulosa cell (GC apoptosis in aged female rats was determined using flow cytometry. In vitro, the effects of AST on cultured GCs were investigated using the MTT proliferation assay and western blot assays. Results: Aged rats had significantly higher GC apoptosis as compared with young female rats. Treatment of aged rats with AST (all three doses; p < 0.01 or Progynova (p < 0.01 significantly reduced GC apoptosis as compared with the aged controls. The proportions of total apoptotic GCs was 25.70%, 86.65%, 47.04%, 27.02%, 42.09% and 56.42% in the normal, aged, 17β-estradiol (E2, high dose AST, medium dose AST, and low dose AST-treated groups, respectively. Significant increases of serum E2 and P4 levels, as well as altered levels of serum follicle stimulating hormone (FSH and luteinizing hormone (LH levels. In cultured rat GCs, AST stimulated GC proliferation, E2 and progesterone (P4 secretion, reduced apoptosis, reduced the level of the pro-apoptotic protein Bcl-2 (p < 0.01, but had no effect on BAX. Conclusions: AST enhanced ovarian function in aged female rats by increasing E2 and P4 levels, and reducing ovarian GC apoptosis via a mechanism involving Bcl-2. These data demonstrate a new pharmacological activity for AST, as well as a novel mechanism of action, and further suggest that AST may be a new therapeutic agent for the management of menopausal symptoms.

  17. Native and tabun-inhibited cholinesterase interactions with oximes

    International Nuclear Information System (INIS)

    Kovarik, Z.; Katalinic, M.; Sinko, G.

    2009-01-01

    The phosphorylation of the serine hydroxyl group in the active site of acetylcholinesterase (AChE) inactivates this essential enzyme in neurotransmission. Its related enzyme butyrylcholinesterase (BChE) also interacts with organophosphorus compounds (OP) scavenging anti-cholinesterase agents and protects synaptic AChE from inhibition. Oximes are reactivators of AChE phosphorylated by OP including insecticides and nerve agents. The effectiveness of oxime-assisted reactivation is primarily attributed to the nucleophilic displacement rate of organophosphate, but efficiency varies with the structure of the bound organophosphate, the structure of the oxime as well as rates of several other cholinesterase's reactions. Besides reactivating cholinesterases, oximes also reversibly inhibit both cholinesterases and protect them from phosphorylation by OP. We tested oximes varying in the type of ring (pyridinium and/or imidazolium), the length and type of the linker between rings, and in the position of the oxime group on the ring to find more effective oximes to reactivate tabun-inhibited human erythrocyte AChE and plasma BChE. Herein we bring an overview of in vitro interactions of native and tabun-inhibited AChE and BChE with oximes together with conformational analysis of the oximes relating molecular properties to their reactivation potency.(author)

  18. Organophosphorus flame retardants and heavy metals in municipal landfill leachate treatment system in Guangzhou, China.

    Science.gov (United States)

    Deng, Mingjun; Kuo, Dave T F; Wu, Qihang; Zhang, Ying; Liu, Xinyu; Liu, Shengyu; Hu, Xiaodong; Mai, Bixian; Liu, Zhineng; Zhang, Haozhi

    2018-05-01

    The occurrence, distribution and removal efficiencies of organophosphorus flame retardants (OPFRs) and metals were examined in a municipal landfill leachate treatment system in Guangzhou, China. Five OPFRs and thirty-five metals were detected in wastewater samples collected at different treatment stages. ∑OPFRs was reduced from 4807.02 ng L -1 to 103.91 ng L -1 through the treatment system, with close to 98% removed from the dissolved phase. Tris(clorisopropyl) phosphates (TCPPs) dominated through the treatment process and accounted for over 80% and 50% of ∑OPFRs at the influent and the effluent, respectively. TCPPs were most efficiently removed (98.6%) followed by tris(2-chloroethyl) phosphate (TCEP) (96.6%) and triphenyl phosphate (TPP) (88.5%). For metals, Fe, Cr, and Rb were dominant in the raw leachate, detected at 7.55, 2.82, and 4.50 mg L -1 , respectively. Thirteen regulated heavy metals - including eight major pollutants (i.e., As. Cd, Cr, Cu, Hg, Ni, Pb, and Zn) - have been detected in all wastewater samples at sub-mg L -1 levels. Over 99.5% removal was achieved for Cr, Ni, and Fe, and close to 95% removal efficiency was observed for Rb. For the eight major heavy metals, over 99% removal was observed; the only exception was Cu, which was removed at 89%. It was found that microfiltration/reverse osmosis was critical for the removal of OPFRs and heavy metals while the core biological treatment played a minor role towards their removal. Remobilization of Co, Cu, Fe, Hg, Mn, Ni, Sb, and Sr from the returned sludge occurred during the second denitrification, indicating the need for additional post-biological process for effective removal of both contaminants. This study highlights the critical need to develop cheap, effective treatment technologies for contaminants-laden leachate generated from open dumps and under-designed landfills. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. Distinct patterns of gene and protein expression elicited by organophosphorus pesticides in Caenorhabditis elegans

    Directory of Open Access Journals (Sweden)

    Dennis William E

    2009-04-01

    Full Text Available Abstract Background The wide use of organophosphorus (OP pesticides makes them an important public health concern. Persistent effects of exposure and the mechanism of neuronal degeneration are continuing issues in OP toxicology. To elucidate early steps in the mechanisms of OP toxicity, we studied alterations in global gene and protein expression in Caenorhabditis elegans exposed to OPs using microarrays and mass spectrometry. We tested two structurally distinct OPs (dichlorvos and fenamiphos and employed a mechanistically different third neurotoxicant, mefloquine, as an out-group for analysis. Treatment levels used concentrations of chemical sufficient to prevent the development of 10%, 50% or 90% of mid-vulval L4 larvae into early gravid adults (EGA at 24 h after exposure in a defined, bacteria-free medium. Results After 8 h of exposure, the expression of 87 genes responded specifically to OP treatment. The abundance of 34 proteins also changed in OP-exposed worms. Many of the genes and proteins affected by the OPs are expressed in neuronal and muscle tissues and are involved in lipid metabolism, cell adhesion, apoptosis/cell death, and detoxification. Twenty-two genes were differentially affected by the two OPs; a large proportion of these genes encode cytochrome P450s, UDP-glucuronosyl/UDP-glucosyltransferases, or P-glycoproteins. The abundance of transcripts and the proteins they encode were well correlated. Conclusion Exposure to OPs elicits a pattern of changes in gene expression in exposed worms distinct from that of the unrelated neurotoxicant, mefloquine. The functional roles and the tissue location of the genes and proteins whose expression is modulated in response to exposure is consistent with the known effects of OPs, including damage to muscle due to persistent hypercontraction, neuronal cell death, and phase I and phase II detoxification. Further, the two different OPs evoked distinguishable changes in gene expression; about half

  20. Tracing organophosphorus and brominated flame retardants and plasticizers in an estuarine food web.

    Science.gov (United States)

    Brandsma, Sicco H; Leonards, Pim E G; Leslie, Heather A; de Boer, Jacob

    2015-02-01

    Nine organophosphorus flame retardants (PFRs) were detected in a pelagic and benthic food web of the Western Scheldt estuary, The Netherlands. Concentrations of several PFRs were an order of magnitude higher than those of the brominated flame retardants (BFRs). However, the detection frequency of the PFRs (6-56%) was lower than that of the BFRs (50-97%). Tris(2-butoxyethyl) phosphate (TBOEP), tris(isobutyl) phosphate (TIBP) and tris(2-chloroisopropyl) phosphate (TCIPP) were the dominant PFRs in sediment with median concentrations of 7.0, 8.1 and 1.8 ng/g dry weight (dw), respectively. PFR levels in the suspended particular matter (SPM) were 2-12 times higher than that in sediment. TBOEP, TCIPP, TIBP, tris(2-chloroethyl) phosphate (TCEP) and tris(phenyl) phosphate (TPHP) were found in organisms higher in the estuarine food web. The highest PFR concentrations in the benthic food web were found in sculpin, goby and lugworm with median concentrations of 17, 7.4, 4.6 and 2.0 ng/g wet weight (ww) for TBOEP, TIBP, TCIPP and TPHP, respectively. Comparable levels were observed in the pelagic food web, BDE209 was the predominant PBDE in sediment and SPM with median concentrations up to 9.7 and 385 ng/g dw, respectively. BDE47 was predominant in the biotic compartment of the food web with highest median levels observed in sculpin and common tern eggs of 79 ng/g lipid weight (lw) (2.5 ng/g ww) and 80 ng/g lw (11 ng/g ww), respectively. Trophic magnification was observed for all PBDEs with the exception of BDE209. Indications of trophic magnification of PFRs were observed in the benthic food web for TBOEP, TCIPP and TCEP with tentative trophic magnification factors of 3.5, 2.2 and 2.6, respectively (pwebs. The relative high PFR levels in several fish species suggest high emissions and substantial exposure of organisms to PFRs in the Western Scheldt. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Analysis of monomeric and oligomeric organophosphorus flame retardants in fish muscle tissues using liquid chromatography–electrospray ionization tandem mass spectrometry: Application to Nile tilapia (Oreochromis niloticus) from an e-waste processing area in northern Vietnam

    OpenAIRE

    Matsukami, Hidenori; Suzuki, Go; Tue, Nguyen Minh; Tuyen, Le Huu; Viet, Pham Hung; Takahashi, Shin; Tanabe, Shinsuke; Takigami, Hidetaka

    2016-01-01

    Using electrospray ionization tandem mass spectrometry combined with liquid chromatography (LC), a novel analytical method was developed to quantify eight monomeric organophosphorus flame retardants (m-PFRs) and three oligomeric organophosphorus flame retardants (o-PFRs) in fish muscle samples. The optimization and validation experiments indicate that the developed method can determine accurately the concentrations of analytes in fish muscle samples. The recoveries of analytes in fish muscle ...

  2. Diminished skeletal muscle microRNA expression with aging is associated with attenuated muscle plasticity and inhibition of IGF-1 signaling

    Science.gov (United States)

    Older individuals have a reduced capacity to induce muscle hypertrophy with resistance exercise (RE), which may contribute to the age-induced loss of muscle mass and function, sarcopenia. We tested the novel hypothesis that dysregulation of microRNAs (miRNAs) may contribute to reduced muscle plastic...

  3. Simultaneous quantification of the organophosphorus pesticides dimethoate and omethoate in porcine plasma and urine by LC-ESI-MS/MS and flow-injection-ESI-MS/MS.

    Science.gov (United States)

    John, Harald; Eddleston, Michael; Clutton, R Eddie; Worek, Franz; Thiermann, Horst

    2010-05-15

    Dimethoate is an organophosphorus toxicant used in agri- and horticulture as a systemic broad-spectrum insecticide. It also exhibits toxic activity towards mammalian organism provoked by catalytic desulfuration in the liver producing its oxon-derivative omethoate thus inhibiting acetylcholinesterase, initiating cholinergic crisis and ultimately leading to death by respiratory paralysis and cardiovascular collapse. Pharmaco- and toxicokinetic studies in animal models help to broaden basic understanding of medical intervention by antidotes and supportive care. Therefore, we developed and validated a LC-ESI-MS/MS method suitable for the simultaneous, selective, precise (RSD(intra-day) 1-8%; RSD(inter-day) 5-14%), accurate (intra-day: 95-107%; inter-day: 90-115%), and robust quantification of both pesticides from porcine urine and plasma after deproteinization by precipitation and extensive dilution (1:11,250 for plasma and 1:40,000 for urine). Accordingly, lower limits of quantification (0.24-0.49 microg/ml plasma and 0.78-1.56 microg/ml urine) and lower limits of detection (0.12-0.24 microg/ml plasma and 0.39-0.78 microg/ml urine) were equivalent to quite low absolute on-column amounts (1.1-2.1 pg for plasma and 2.0-3.9 pg for urine). The calibration range (0.24-250 microg/ml plasma and 0.78-200 microg/ml urine) was subdivided into two linear ranges (r(2)>or=0.998) each covering nearly two orders of magnitude. The lack of any interfering peak in 6 individual blank specimens from plasma and urine demonstrated the high selectivity of the method. Furthermore, extensive sample dilution causing lowest concentration of potentially interfering matrix ingredients prompted us to develop and validate an additional flow-injection method (FI-ESI-MS/MS). Validation characteristics were as good as for the chromatographic method but sample throughput was enhanced by a factor of 6. Effects on ionization provoked by plasma and urine matrix from 6 individuals as well as in the

  4. A comprehensive evaluation of the efficacy of leading oxime therapies in guinea pigs exposed to organophosphorus chemical warfare agents or pesticides

    Energy Technology Data Exchange (ETDEWEB)

    Wilhelm, Christina M., E-mail: wilhelmc@battelle.org [Battelle, 505 King Avenue, JM-7, Columbus, OH 43201-2693 (United States); Snider, Thomas H., E-mail: snidert@battelle.org [Battelle, 505 King Avenue, JM-7, Columbus, OH 43201-2693 (United States); Babin, Michael C., E-mail: babinm@battelle.org [Battelle, 505 King Avenue, JM-7, Columbus, OH 43201-2693 (United States); Jett, David A., E-mail: jettd@ninds.nih.gov [National Institutes of Health/National Institute of Neurological Disorders and Stroke, Bethesda, MD 20892 (United States); Platoff, Gennady E., E-mail: platoffg@niaid.nih.gov [National Institutes of Health/National Institute of Allergy and Infectious Diseases, Bethesda, MD 20892 (United States); Yeung, David T., E-mail: dy70v@nih.gov [National Institutes of Health/National Institute of Neurological Disorders and Stroke, Bethesda, MD 20892 (United States)

    2014-12-15

    The currently fielded pre-hospital therapeutic regimen for the treatment of organophosphorus (OP) poisoning in the United States (U.S.) is the administration of atropine in combination with an oxime antidote (2-PAM Cl) to reactivate inhibited acetylcholinesterase (AChE). Depending on clinical symptoms, an anticonvulsant, e.g., diazepam, may also be administered. Unfortunately, 2-PAM Cl does not offer sufficient protection across the range of OP threat agents, and there is some question as to whether it is the most effective oxime compound available. The objective of the present study is to identify an oxime antidote, under standardized and comparable conditions, that offers protection at the FDA approved human equivalent dose (HED) of 2-PAM Cl against tabun (GA), sarin (GB), soman (GD), cyclosarin (GF), and VX, and the pesticides paraoxon, chlorpyrifos oxon, and phorate oxon. Male Hartley guinea pigs were subcutaneously challenged with a lethal level of OP and treated at approximately 1 min post challenge with atropine followed by equimolar oxime therapy (2-PAM Cl, HI-6 DMS, obidoxime Cl{sub 2}, TMB-4, MMB4-DMS, HLö-7 DMS, MINA, and RS194B) or therapeutic-index (TI) level therapy (HI-6 DMS, MMB4-DMS, MINA, and RS194B). Clinical signs of toxicity were observed for 24 h post challenge and blood cholinesterase [AChE and butyrylcholinesterase (BChE)] activity was analyzed utilizing a modified Ellman's method. When the oxime is standardized against the HED of 2-PAM Cl for guinea pigs, the evidence from clinical observations, lethality, quality of life (QOL) scores, and cholinesterase reactivation rates across all OPs indicated that MMB4 DMS and HLö-7 DMS were the two most consistently efficacious oximes. - Highlights: • First comprehensive evaluation of leading AChE oxime reactivators • All oximes are compared against current U.S. therapy 2-PAM Cl. • Relative therapeutic oxime efficacies against OP CWNA and pesticides • Contribution to more effective

  5. Nifedipine, a calcium channel blocker, inhibits advanced glycation end product (AGE)-elicited mesangial cell damage by suppressing AGE receptor (RAGE) expression via peroxisome proliferator-activated receptor-gamma activation

    International Nuclear Information System (INIS)

    Matsui, Takanori; Yamagishi, Sho-ichi; Takeuchi, Masayoshi; Ueda, Seiji; Fukami, Kei; Okuda, Seiya

    2009-01-01

    The interaction between advanced glycation end products (AGE) and their receptor RAGE mediates the progressive alteration in renal architecture and loss of renal function in diabetic nephropathy. Oxidative stress generation and inflammation also play a central role in diabetic nephropathy. This study investigated whether and how nifedipine, a calcium channel blocker (CCB), blocked the AGE-elicited mesangial cell damage in vitro. Nifedipine, but not amlodipine, a control CCB, down-regulated RAGE mRNA levels and subsequently reduced reactive oxygen species (ROS) generation in AGE-exposed mesangial cells. AGE increased mRNA levels of vascular cell adhesion molecule-1 (VCAM-1) and induced monocyte chemoattractant protein-1 (MCP-1) production in mesangial cells, both of which were prevented by the treatment with nifedipine, but not amlodipine. The beneficial effects of nifedipine on AGE-exposed mesangial cells were blocked by the simultaneous treatment of GW9662, an inhibitor of peroxisome proliferator-activated receptor-γ (PPAR-γ). Although nifedipine did not affect expression levels of PPAR-γ, it increased the PPAR-γ transcriptional activity in mesangial cells. Our present study provides a unique beneficial aspect of nifedipine on diabetic nephropathy; it could work as an anti-inflammatory agent against AGE by suppressing RAGE expression in cultured mesangial cells via PPAR-γ activation.

  6. Dietary nitrate improves age-related hypertension and metabolic abnormalities in rats via modulation of angiotensin II receptor signaling and inhibition of superoxide generation

    DEFF Research Database (Denmark)

    Hezel, M.; Peleli, Maria; Liu, M.

    2016-01-01

    . Finally, nitrate treatment in aged rats normalized the gene expression profile of ANG II receptors (AT1A, AT2, AT1A/AT2 ratio) in the renal and cardiovascular systems without altering plasma levels of renin or ANG II. Our results show that boosting the nitrate-nitrite-NO pathway can partly compensate...... that increased angiotensin II (ANG II) signaling is also implicated in the pathogenesis of endothelial dysfunction and hypertension by accelerating formation of reactive oxygen species. This study was designed to test the hypothesis that dietary nitrate supplementation could reduce blood pressure and improve...... glucose tolerance in aged rats, via attenuation of NADPH oxidase activity and ANG II receptor signaling. Dietary nitrate supplementation for two weeks reduced blood pressure (10–15 mmHg) and improved glucose clearance in old, but not in young rats. These favorable effects were associated with increased...

  7. Compostos organofosforados pentavalentes: histórico, métodos sintéticos de preparação e aplicações como inseticidas e agentes antitumorais Organophosphorus pentavalent compounds: history, synthetic methods of preparation and application as insecticides and antitumor agents

    Directory of Open Access Journals (Sweden)

    Viviane Martins Rebello dos Santos

    2007-02-01

    Full Text Available This paper is a review of the history, synthesis and application of organophosphorus compounds, especially of those of pentavalent phosphorus, such as phosphoramidates, phosphorothioates, phosphonates and phosphonic acids with insecticide and anticancer activities. The organophosphorus compounds with agrochemical applications show great structural variety, They include not only insecticides, but also fungicides, herbicides, and others. The large variety of commercially available organophosphorus pesticides is remarkable. Even more interesting is the high efficiency of some organophosphorus compounds as anticancer agents such as cyclophosphamide and its derivatives.

  8. Degradation of Organophosphorus Pesticides in Water during UV/H2O2 Treatment: Role of Sulphate and Bicarbonate Ions

    Directory of Open Access Journals (Sweden)

    Am Fadaei

    2012-01-01

    Full Text Available The photodegradation of two organophosphorus pesticides, malathian and diazinon, by sulfate radicals and bicarbonate radicals in aqueous solution were studied. The effect of the operational parameters such as pH, salt concentration, water type, H2O2 concentration and initial concentration of pesticides was studied. Gas chromatography mass spectroscopy (GC–MS was used for analyses of pesticides. When salt effect was studied, it was found that sodium bicarbonate was the most powerful inhibitor used, while sodium sulfate was the weakest one. The highest degradation in UV/H2O2 process for malathion was found in alkaline condition and for diazinon in acidic condition. The photodegradation in all waters used in this work exhibited first order kinetics. Photodegradation rate in distilled water was higher than real water. The degradation of pesticides increased with increasing of H2O2 concentration.

  9. [Comparative analysis of sensitivity of proteases (chymotrypsin and trypsin) and cholinesterases of different origin to some organophosphorus inhibitors].

    Science.gov (United States)

    Rozengart, E V

    2009-01-01

    The antichymotrypsin, antitrypsin, and anticholinesterase efficiencies of four homologous series of organophosphorus inhibitors are compared: O-ethyl-S-(n-alkyl)methylthiophosphonates, O-(n-alkyl)-S-(n-butyl)methylthiophosphonates, O-(n-alkyl)-S-beta-(ethylmercaptoethylene)methylthiophosphonates, and their methylsulfomethylates. As sources of a-chymotrypsin and trypsin, commercial compounds of Worthington Biochemical Corporation and Leningrad Myasokombinat were tested. Bimolecular constant of the reaction rate was used as the measure of antienzyme efficiency. In all cases, the antichymotrypsin efficiency was lower, while the antitrypsin--essentially higher than the anticholinesterase activity of the studied inhibitors. These differences were found to much depend both on the inhibitor structure and on nature of the cholinesterase compounds.

  10. Towards a Capacitive Enzyme Sensor for Direct Determination of Organophosphorus Pesticides: Fundamental Studies and Aspects of Development

    Directory of Open Access Journals (Sweden)

    Ashok Mulchandani

    2003-06-01

    Full Text Available The realisation of a miniaturised potentiometric enzyme biosensor is presented. The biosensor chip utilises the enzyme organophosphorus hydrolase (OPH for the direct determination of pesticides. The transducer structure of the sensors chip consists of a pH-sensitive capacitive electrolyte-insulator-semiconductor (EIS structure that reacts towards pH changes caused by the OPH-catalised hydrolysis of the organophosphate compounds. The biosensor is operated versus a conventional Ag/AgCl reference electrode. Measurements were performed in the capacitance/voltage (C/V and the constant capacitance (ConCap mode for the two different pesticides paraoxon and parathion. For the development of this new type of biosensor, different immobilisation strategies, influence of buffer composition and concentration, transducer material, detection limit, long-term stability and selectivity have been studied.

  11. Corrosion inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, A O

    1965-12-29

    An acid corrosion-inhibiting composition consists essentially of a sugar, and an alkali metal salt selected from the group consisting of iodides and bromides. The weight ratio of the sugar to the alkali metal salt is between 2:1 and about 20,000:1. Also, a corrosion- inhibited phosphoric acid composition comprising at least about 20 wt% of phosphoric acid and between about 0.1 wt% and about 10 wt% of molasses, and between about 0.0005 wt% and about 1 wt% of potassium iodide. The weight ratio of molasses to iodide is greater than about 2:1. (11 claims)

  12. Caffeic acid attenuates the inflammatory stress induced by glycated LDL in human endothelial cells by mechanisms involving inhibition of AGE-receptor, oxidative, and endoplasmic reticulum stress.

    Science.gov (United States)

    Toma, Laura; Sanda, Gabriela M; Niculescu, Loredan S; Deleanu, Mariana; Stancu, Camelia S; Sima, Anca V

    2017-09-10

    Type 2 diabetes mellitus is a worldwide epidemic and its atherosclerotic complications determine the high morbidity and mortality of diabetic patients. Caffeic acid (CAF), a phenolic acid present in normal diets, is known for its antioxidant properties. The aim of this study was to investigate CAF's anti-inflammatory properties and its mechanism of action, using cultured human endothelial cells (HEC) incubated with glycated low-density lipoproteins (gLDL). Levels of the receptor for advanced glycation end-products (RAGE), inflammatory stress markers (C reactive protein, CRP; vascular cell adhesion molecule-1, VCAM-1; monocyte chemoattractant protein-1, MCP-1), and oxidative stress and endoplasmic reticulum stress (ERS) markers were evaluated in gLDL-exposed HEC, in the presence/absence of CAF. RAGE silencing or blocking, specific inhibitors for oxidative stress (apocynin, N-acetyl-cysteine), and ERS (salubrinal) were used. The results showed that: (i) gLDL induced CRP synthesis and secretion through mechanisms involving NADPH oxidase-dependent oxidative stress and ERS in HEC; (ii) gLDL-RAGE interaction, oxidative stress, and ERS stimulated the secretion of VCAM-1 and MCP-1 in HEC; and (iii) CAF reduced the secretion of CRP, VCAM-1, and MCP-1 in gLDL-exposed HEC by inhibiting RAGE expression, oxidative stress, and ERS. In conclusion, CAF might be a promising alternative to ameliorate a wide spectrum of disorders due to its complex mechanisms of action resulting in anti-inflammatory and antioxidative properties. © 2017 BioFactors, 43(5):685-697, 2017. © 2017 International Union of Biochemistry and Molecular Biology.

  13. Determination of no-observed effect level (NOEL-biomarker equivalents to interpret biomonitoring data for organophosphorus pesticides in children

    Directory of Open Access Journals (Sweden)

    Bouchard Michèle

    2009-02-01

    Full Text Available Abstract Background Environmental exposure to organophosphorus pesticides has been characterized in various populations, but interpretation of these data from a health risk perspective remains an issue. The current paper proposes biological reference values to help interpret biomonitoring data related to an exposure to organophosphorus pesticides in children for which measurements of alkylphosphate metabolites are available. Methods Published models describing the kinetics of malathion and chlorpyrifos in humans were used to determine no-observed effect level – biomarker equivalents for methylphosphates and ethylphosphates, respectively. These were expressed in the form of cumulative urinary amounts of alkylphosphates over specified time periods corresponding to an absorbed no-observed effect level dose (derived from a published human exposure dose and assuming various plausible exposure scenarios. Cumulative amounts of methylphosphate and ethylphosphate metabolites measured in the urine of a group of Quebec children were then compared to the proposed biological reference values. Results From a published no-observed effect level dose for malathion and chlorpyrifos, the model predicts corresponding oral biological reference values for methylphosphate and ethylphosphate derivatives of 106 and 52 nmol/kg of body weight, respectively, in 12-h nighttime urine collections, and dermal biological reference values of 40 and 32 nmol/kg of body weight. Out of the 442 available urine samples, only one presented a methylphosphate excretion exceeding the biological reference value established on the basis of a dermal exposure scenario and none of the methylphosphate and ethylphosphate excretion values were above the obtained oral biological reference values, which reflect the main exposure route in children. Conclusion This study is a first step towards the development of biological guidelines for organophophorus pesticides using a toxicokinetic modeling

  14. Determination of some organophosphorus pesticides in water and watermelon samples by microextraction prior to high-performance liquid chromatography.

    Science.gov (United States)

    Wang, Chun; Wu, Qiuhua; Wu, Chunxia; Wang, Zhi

    2011-11-01

    A novel method based on simultaneous liquid-liquid microextraction and carbon nanotube reinforced hollow fiber microporous membrane solid-liquid phase microextraction has been developed for the determination of six organophosphorus pesticides, i.e. isocarbophos, phosmet, parathion-methyl, triazophos, fonofos and phoxim, in water and watermelon samples prior to high-performance liquid chromatography (HPLC). Under the optimum conditions, the method shows a good linearity within a range of 1-200 ng/mL for water samples and 5-200 ng/g for watermelon samples, with the correlation coefficients (r) varying from 0.9990 to 0.9997 and 0.9986 to 0.9995, respectively. The limits of detection (LODs) were in the range between 0.1 and 0.3 ng/mL for water samples and between 1.0 and 1.5 ng/g for watermelon samples. The recoveries of the method at spiking levels of 5.0 and 50.0 ng/mL for water samples were between 85.4 and 100.8%, and at spiking levels of 5.0 and 50.0 ng/g for watermelon samples, they were between 82.6 and 92.4%, with the relative standard deviations (RSDs) varying from 4.5-6.9% and 5.2-7.4%, respectively. The results suggested that the developed method represents a simple, low-cost, high analytes preconcentration and excellent sample cleanup procedure for the determination of organophosphorus pesticides in water and watermelon samples. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Rapid simultaneous determination of organophosphorus pesticides in human serum and urine by liquid chromatography-mass spectrometry

    Directory of Open Access Journals (Sweden)

    Zlatković Milica

    2010-01-01

    Full Text Available Background/Aim. Analysis of organophosphosphorus compounds and their metabolites in a biological material includes the use of numerous methods, covering both preparation of samples for analysis and their identification that is considered to be very complex. Low concentrations monitoring requires implementation of highly sensitive analytical techniques. The aim of this study was to develop and validate an original and sensitive method for the detection and quantitation of organophosphorus pesticides (dimethoate, diazinon, malathion and malaoxon in human biological matrices (serum, urine. Methods. This method was based on a solid-phase extraction procedure, a chromatographic separation using an ACQUITY UPLC ® HSST3 column and mass spectrometric detection in the positve ion mode. Mobile phase: was consited of Solvent A (5 mM ammonium formate pH 3.0 and Solvent B (0.1% acetic formate in methanol, in a linear gradient (constant flow-rate 0.3 mL/min. Results. The standard curve was linear in the range of 0.05-5.00 mg/L for malathion and malaoxon, 0.10-5.00 mg/L for dimethoate and 0.05-2.50 mg/L for diazinon. The correlation coefficient was r ≥ 0.99. Extraction recoveries were satisfactory and ranged between 90-99%. The limits of detection (LOD was between 0.007- 0.07 mg/L and the limits of quantitation (LOQ ranged between 0.022-0.085 mg/L. Intra- and interassay precision and accuracy were satisfactory for all of the pesticides analyzed. Conclusion. The method of liquid chromatography - mass spectrometry is simple, accurate, and useful for the determination of organophosphorus pesticides in both clinical and forensic toxicology.

  16. Sol-gel niobia sorbent with a positively charged octadecyl ligand providing enhanced enrichment of nucleotides and organophosphorus pesticides in capillary microextraction for online HPLC analysis.

    Science.gov (United States)

    Kesani, Sheshanka; Malik, Abdul

    2018-04-01

    A niobia-based sol-gel organic-inorganic hybrid sorbent carrying a positively charged C 18 ligand (Nb 2 O 5 -C 18 (+ve)) was synthesized to achieve enhanced enrichment capability in capillary microextraction of organophosphorus compounds (which include organophosphorus pesticides and nucleotides) before their online analysis by high-performance liquid chromatography. The sorbent was designed to simultaneously provide three different types of molecular level interactions: electrostatic, Lewis acid-base, and van der Waals interactions. To understand relative contributions of various molecular level analyte-sorbent interactions in the extraction process, two other sol-gel niobia sorbents were also created: (a) a purely inorganic sol-gel niobia sorbent (Nb 2 O 5 ) and (b) an organic-inorganic hybrid sol-gel niobia sorbent carrying an electrically neutral-bonded octadecyl ligand (Nb 2 O 5 -C 18 ). The extraction efficiency of the created sol-gel niobia sorbent (Nb 2 O 5 -C 18 (+ve)) was compared with that of analogously designed and synthesized titania-based sol-gel sorbent (TiO 2 -C 18 (+ve)), taking into consideration that titania-based sorbents present state-of-the-art extraction media for organophosphorus compounds. In capillary microextraction with high-performance liquid chromatography analysis, Nb 2 O 5 -C 18 (+ve) had shown 40-50% higher specific extraction values (a measure of extraction efficiency) over that of TiO 2 -C 18 (+ve). Compared to TiO 2 -C 18 (+ve), Nb 2 O 5 -C 18 (+ve) also provided superior analyte desorption efficiency (96 vs. 90%) during the online release of the extracted organophosphorus pesticides from the sorbent coating in the capillary microextraction capillary to the chromatographic column using reversed-phase high-performance liquid chromatography mobile phase. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. A SAW-Based Chemical Sensor for Detecting Sulfur-Containing Organophosphorus Compounds Using a Two-Step Self-Assembly and Molecular Imprinting Technology

    Directory of Open Access Journals (Sweden)

    Yong Pan

    2014-05-01

    Full Text Available This paper presents a new effective approach for the sensitive film deposition of surface acoustic wave (SAW chemical sensors for detecting organophosphorus compounds such as O-ethyl-S-2-diisopropylaminoethyl methylphosphonothiolate (VX containing sulfur at extremely low concentrations. To improve the adsorptive efficiency, a two-step technology is proposed for the sensitive film preparation on the SAW delay line utilizing gold electrodes. First, mono[6-deoxy-6-[(mercaptodecamethylenethio

  18. Actinide immobilization in the subsurface environment by in-situ treatment with a hydrolytically unstable organophosphorus complexant: Uranyl uptake by calcium phytate

    International Nuclear Information System (INIS)

    Nash, K.L.; Jensen, M.P.; Schmidt, M.A.

    1997-01-01

    In addition to naturally occurring uranium and thorium, actinide ions exist in the subsurface environment as a result of accidental releases and intentional disposal practices associated with nuclear weapons production. These species present a significant challenge to cost-effective remediation of contaminated environments. An attractive approach to decreasing the probability of actinide migration in the subsurface is to transform the ions into a less mobile form by remote treatment. We have under development a process which relies on a polyfunctional organophosphorus complexant to sequester the mobile metal ions by complexation/cation exchange in the near term, and to subsequently decompose, transforming the actinides into insoluble phosphate mineral forms in the long term. Studies to date include identification of a suitable organophosphorus reagent, profiling of its decomposition kinetics, verification of the formation of phosphate mineral phases upon decomposition of the reagent, and extensive comparison of the actinide uptake ability of the calcium salt of the reagent as compared with hydroxyapatite. In this report, we briefly describe the process with focus on the cation exchange behavior of the calcium salt of the organophosphorus sequestrant

  19. [Feasibility investigation of hydrogen instead of helium as carrier gas in the determination of five organophosphorus pesticides by gas chromatography-mass spectrometry].

    Science.gov (United States)

    Liu, Zhenxue; Zhou, Shixue

    2015-01-01

    Helium is almost the only choosable carrier gas used in gas chromatography-mass spectrometry (GC-MS). A mixed standard solution of five organophosphorus pesticides was analyzed by using GC-MS, and hydrogen or helium as carrier gas, so as to study the feasibility of hydrogen instead of helium as carrier gas for the determination of organophosphorus pesticides. Combining a mass spectrum database built by ourselves, the results were deconvolved and identified by Automated Mass Spectral Deconvolution & Identification System (AMDIS32), a software belonging to the workstation of the instrument. Then, the statistical software, IBM SPSS Statistics 19.0 was used for the clustering analysis of the data. The results indicated that when hydrogen was used as carrier gas, the peaks of the pesticides detected were slightly earlier than those when helium used as carrier gas, but the resolutions of the chromatographic peaks were lower, and the fraction good indices (Frac. Good) were lower, too. When hydrogen was used as carrier gas, the signals of the pesticides were unstable, the measuring accuracies of the pesticides were reduced too, and even more, some compounds were undetectable. Therefore, considering the measuring accuracy, the signal stability, and the safety, etc., hydrogen should be cautiously used as carrier gas in the determination of organophosphorus pesticides by GC-MS.

  20. Comparison of the Efficiency of Simultaneous Application of UV/O3 for the Removal of Organophosphorus and Carbamat Pesticides in Aqueous Solutions

    Directory of Open Access Journals (Sweden)

    Mohammad Taghi Samadi

    2010-03-01

    Full Text Available A vast variety of pesticides are used for agricultural pests in Iran. The release of these persistent organic pollutants. into water supplies leaves adverse effects on both the environment and public health. Advanced oxidation processes have been used recently for pesticide removal. In this research, the combined UV/O3 process has been investigated for the removal of organophosphorus pesticides (Diazinon, Chlorpyrifos, Carbamate pesticides (carbaryl. In this survey, samples have been prepared by adding given concentration (1, 5, 10, 15, 20 mg/L of the pesticides to deionized water. The samples at separation periods were exposed to the combined UV/O3 (UV=50-200 Wm-2 and O3 = 1g hr-1in a bath  reactor at different pH levels (6, 7, 9 and for different contact times (0.5,1,1.5,2 hr and the removal efficiencies were determined. Residual concentrations were determined using GC/MS/MS and HPLC.  Based on the results, increasing pH reduced pesticide concentration and increased contact time had a direct effect on enhancing removal efficiency. The combined UV/O3 process was found to have a high efficiency (>80% in degrading both halogenated Organophosphorus(Chlorpyrifos and non- halogenated Organophosphorus (Diazinon pesticides. Its removal efficiency for degrading carbamate pesticide (Carbari was found to be >90%. Based on our results, this method may be suggested for the removal of pesticides from aqueous solutions.

  1. Retrospective detection of exposure to organophosphorus anti-cholinesterases: Mass spectrometric analysis of phosphylated human butyrylcholinesterase

    NARCIS (Netherlands)

    Fidder, A.; Hulst, A.G.; Noort, D.; Ruiter, R. de; Schans, M.J. van der; Benschop, H.P.; Langenberg, J.P.

    2002-01-01

    In this paper a novel and general procedure is presented for detection of organophosphate-inhibited human butyrylcholinesterase (HuBuChE), which is based on electrospray tandem mass spectrometric analysis of phosphylated nonapeptides obtained after pepsin digestion of the enzyme. The utility of this

  2. Determination of organophosphorus pesticides in water samples by using a new sensitive luminescent probe of Eu (III) complex

    Energy Technology Data Exchange (ETDEWEB)

    Azab, Hassan A., E-mail: azab2@yahoo.com; Anwar, Z.M.; Rizk, M.A.; Khairy, Gasser M.; El-Asfoury, M.H.

    2015-01-15

    This work describes the application of fluorescence for investigating the interactions of Eu(III)-TAN-1,10 phenanthroline (where TAN=4,4,4-Trifluoro-1-(2-naphthyl)-1,3-butanedione) with pesticides Chlorpyrifos, Malathion, Endosulfan, Heptachlor. The complex was synthesized and characterized by elemental analysis, FTIR, x-ray spectroscopy, solid fluorescence and thermal analysis. The results indicated that the composition of this complex is [Eu(TAN){sub 2}(Phen)(H{sub 2}O){sub 2}]Cl. The luminescence properties of the complex in different solvents and at different pH values have been investigated. The results show that the complex exhibits more efficient luminescence at pH=7.5. The interactions of Eu-complex with different pesticides (Chlorpyrifos, Malathion, Endosulfan, and Heptachlor) in aqueous medium have been investigated by fluorescence measurements. The luminescence intensity of the probe is quenched by Malathion and enhanced by (Endosulfan, Heptachlor, and Chlorpyrifos). Direct methods for the determination of the pesticides under investigation have been developed using the luminescence variations of the probe in solution. The detection limits are 0.47, 1.02, 0.66, 0.64 µmol/L for Chlorpyrifos, Endosulfan, Heptachlor, and Malathion, respectively. The binding constants and thermodynamic parameters of the pesticides with probe were evaluated. The emission quantum yield (QY=0.71) of Eu(III)-complex was determined using tris (2,2'-bipyridyl) dichlororuthenium(II) hexahydrate. A thermodynamic analysis showed that the reaction is spontaneous with negative ΔG. Effect of some relevant interferents on the detection of pesticides has been investigated. The new method was applied to the determination of the pesticides in different types of water samples (tap, river, and waste water). - Highlights: • A new luminescent probe of Eu (III) complex has been developed for sensing some organophosphorus pesticides. • Four guest pesticides Chlorpyrifos, Malathion

  3. Determination of organophosphorus pesticides in water samples by using a new sensitive luminescent probe of Eu (III) complex

    International Nuclear Information System (INIS)

    Azab, Hassan A.; Anwar, Z.M.; Rizk, M.A.; Khairy, Gasser M.; El-Asfoury, M.H.

    2015-01-01

    This work describes the application of fluorescence for investigating the interactions of Eu(III)-TAN-1,10 phenanthroline (where TAN=4,4,4-Trifluoro-1-(2-naphthyl)-1,3-butanedione) with pesticides Chlorpyrifos, Malathion, Endosulfan, Heptachlor. The complex was synthesized and characterized by elemental analysis, FTIR, x-ray spectroscopy, solid fluorescence and thermal analysis. The results indicated that the composition of this complex is [Eu(TAN) 2 (Phen)(H 2 O) 2 ]Cl. The luminescence properties of the complex in different solvents and at different pH values have been investigated. The results show that the complex exhibits more efficient luminescence at pH=7.5. The interactions of Eu-complex with different pesticides (Chlorpyrifos, Malathion, Endosulfan, and Heptachlor) in aqueous medium have been investigated by fluorescence measurements. The luminescence intensity of the probe is quenched by Malathion and enhanced by (Endosulfan, Heptachlor, and Chlorpyrifos). Direct methods for the determination of the pesticides under investigation have been developed using the luminescence variations of the probe in solution. The detection limits are 0.47, 1.02, 0.66, 0.64 µmol/L for Chlorpyrifos, Endosulfan, Heptachlor, and Malathion, respectively. The binding constants and thermodynamic parameters of the pesticides with probe were evaluated. The emission quantum yield (QY=0.71) of Eu(III)-complex was determined using tris (2,2'-bipyridyl) dichlororuthenium(II) hexahydrate. A thermodynamic analysis showed that the reaction is spontaneous with negative ΔG. Effect of some relevant interferents on the detection of pesticides has been investigated. The new method was applied to the determination of the pesticides in different types of water samples (tap, river, and waste water). - Highlights: • A new luminescent probe of Eu (III) complex has been developed for sensing some organophosphorus pesticides. • Four guest pesticides Chlorpyrifos, Malathion, Endosulfan, and

  4. Luminescence recognition of different organophosphorus pesticides by the luminescent Eu(III)–pyridine-2,6-dicarboxylic acid probe

    International Nuclear Information System (INIS)

    Azab, Hassan A.; Duerkop, Axel; Anwar, Z.M.; Hussein, Belal H.M.; Rizk, Moustafa A.; Amin, Tarek

    2013-01-01

    Highlights: ► Europium (III) luminescence quenching has been used for sensing organophosphorous pesticides. ► Four guest pesticides chlorfenvinphos, malathion, azinphos, and paraxon ethyl were used. ► A sensitive rapid, cheap direct method for the determination of the pesticides has been developed. ► The method was applied to the determination of the OPs in tap, river, mineral, and waste waters. - Abstract: Luminescence quenching of a novel long lived Eu(III)–pyridine-2,6-dicarboxylic acid probe of 1:2 stoichiometric ratio has been studied in 0.10 volume fraction ethanol–water mixture at pH 7.5 (HEPES buffer) in the presence of the organophosphorus pesticides chlorfenvinphos (P1), malathion (P2), azinphos (P3), and paraxon ethyl (P4). The luminescence intensity of Eu(III)–(PDCA) 2 probe decreases as the concentration of the pesticide increases. It was observed that the quenching due to P3 and P4 proceeds via both diffusional and static quenching processes. Direct methods for the determination of the pesticides under investigation have been developed using the luminescence quenching of Eu(III)–pyridine-2,6-dicarboxylic acid probe in solution. The linear range for determination of the selected pesticides is 1.0–35.0 μM. The detection limits were 0.24–0.55 μM for P3, P4, and P1 and 2.5 μM for P2, respectively. The binding constants (K), and thermodynamic parameters of the OPs with Eu(III)–(PDCA) 2 were evaluated. Positive and negative values of entropy (ΔS) and enthalpy (ΔH) changes for Eu(III)–(PDCA) 2 –P1 ternary complex were calculated. As the waters in this study do not contain the above mentioned OPs over the limit detectable by the method, a recovery study was carried out after the addition of the adequate amounts of the organophosphorus pesticides under investigation.

  5. Luminescence recognition of different organophosphorus pesticides by the luminescent Eu(III)-pyridine-2,6-dicarboxylic acid probe

    Energy Technology Data Exchange (ETDEWEB)

    Azab, Hassan A., E-mail: azab2@yahoo.com [Chemistry Department, Faculty of Science, Suez Canal University, Ismailia 41522 (Egypt); Duerkop, Axel [Institute of Analytical Chemistry, Chemo and Biosensors, Regensburg University, D-93040 Regensburg (Germany); Anwar, Z.M.; Hussein, Belal H.M.; Rizk, Moustafa A.; Amin, Tarek [Chemistry Department, Faculty of Science, Suez Canal University, Ismailia 41522 (Egypt)

    2013-01-08

    Highlights: Black-Right-Pointing-Pointer Europium (III) luminescence quenching has been used for sensing organophosphorous pesticides. Black-Right-Pointing-Pointer Four guest pesticides chlorfenvinphos, malathion, azinphos, and paraxon ethyl were used. Black-Right-Pointing-Pointer A sensitive rapid, cheap direct method for the determination of the pesticides has been developed. Black-Right-Pointing-Pointer The method was applied to the determination of the OPs in tap, river, mineral, and waste waters. - Abstract: Luminescence quenching of a novel long lived Eu(III)-pyridine-2,6-dicarboxylic acid probe of 1:2 stoichiometric ratio has been studied in 0.10 volume fraction ethanol-water mixture at pH 7.5 (HEPES buffer) in the presence of the organophosphorus pesticides chlorfenvinphos (P1), malathion (P2), azinphos (P3), and paraxon ethyl (P4). The luminescence intensity of Eu(III)-(PDCA){sub 2} probe decreases as the concentration of the pesticide increases. It was observed that the quenching due to P3 and P4 proceeds via both diffusional and static quenching processes. Direct methods for the determination of the pesticides under investigation have been developed using the luminescence quenching of Eu(III)-pyridine-2,6-dicarboxylic acid probe in solution. The linear range for determination of the selected pesticides is 1.0-35.0 {mu}M. The detection limits were 0.24-0.55 {mu}M for P3, P4, and P1 and 2.5 {mu}M for P2, respectively. The binding constants (K), and thermodynamic parameters of the OPs with Eu(III)-(PDCA){sub 2} were evaluated. Positive and negative values of entropy ({Delta}S) and enthalpy ({Delta}H) changes for Eu(III)-(PDCA){sub 2}-P1 ternary complex were calculated. As the waters in this study do not contain the above mentioned OPs over the limit detectable by the method, a recovery study was carried out after the addition of the adequate amounts of the organophosphorus pesticides under investigation.

  6. Purple sweet potato color alleviates D-galactose-induced brain aging in old mice by promoting survival of neurons via PI3K pathway and inhibiting cytochrome C-mediated apoptosis.

    Science.gov (United States)

    Lu, Jun; Wu, Dong-mei; Zheng, Yuan-lin; Hu, Bin; Zhang, Zi-feng

    2010-05-01

    Purple sweet potato color (PSPC), a class of naturally occurring anthocyanins, protects brain function against oxidative stress induced by D-galactose (D-gal) (Sigma-Aldrich, St. Louis, MO, USA). Our data showed that PSPC enhanced open-field activity, decreased step-through latency, and improved spatial learning and memory ability in D-gal-treated old mice by decreasing advanced glycation end-products' (AGEs) formation and the AGE receptor (RAGE) expression, and by elevating Cu,Zn-superoxide dismutase (Cu,Zn-SOD) (Sigma-Aldrich) and catalase (CAT) expression and activity. Cleavage of caspase-3 and increased terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate (dUTP) nick-end-labeling (TUNEL)-positive cells in D-gal-treated old mice were inhibited by PSPC, which might be attributed to its antioxidant property. PSPC also suppressed the activation of c-Jun NH(2)-terminal kinase (JNK) and the release of cytochrome c from mitochondria that counteracted the onset of neuronal apoptosis in D-gal-treated old mice. Furthermore, it was demonstrated that phosphoinositide 3-kinase (PI3K) activation was required for PSPC to promote the neuronal survival accompanied with phosphorylation and activation of Akt and p44/42 mitogen-activated protein kinase (MAPK) by using PI3K inhibitor LY294002 (Cell Signaling Technology, Inc., Beverly, MA, USA), implicating a neuronal survival mechanism. The present results suggest that neuronal survival promoted by PSPC may be a potentially effective method to enhance resistance of neurons to age-related disease.

  7. Optical Detection of Paraoxon Using Single-Walled Carbon Nanotube Films with Attached Organophosphorus Hydrolase-Expressed Escherichia coli

    Directory of Open Access Journals (Sweden)

    Intae Kim

    2015-05-01

    Full Text Available In whole-cell based biosensors, spectrophotometry is one of the most commonly used methods for detecting organophosphates due to its simplicity and reliability. The sensor performance is directly affected by the cell immobilization method because it determines the amount of cells, the mass transfer rate, and the stability. In this study, we demonstrated that our previously-reported microbe immobilization method, a microbe-attached single-walled carbon nanotube film, can be applied to whole-cell-based organophosphate sensors. This method has many advantages over other whole-cell organophosphate sensors, including high specific activity, quick cell immobilization, and excellent stability. A device with circular electrodes was fabricated for an enlarged cell-immobilization area. Escherichia coli expressing organophosphorus hydrolase in the periplasmic space and single-walled carbon nanotubes were attached to the device by our method. Paraoxon was hydrolyzed using this device, and detected by measuring the concentration of the enzymatic reaction product, p-nitrophenol. The specific activity of our device was calculated, and was shown to be over 2.5 times that reported previously for other whole-cell organophosphate sensors. Thus, this method for generation of whole-cell-based OP biosensors might be optimal, as it overcomes many of the caveats that prevent the widespread use of other such devices.

  8. Heat Release Property and Fire Performance of the Nomex/Cotton Blend Fabric Treated with a Nonformaldehyde Organophosphorus System

    Directory of Open Access Journals (Sweden)

    Charles Q. Yang

    2016-09-01

    Full Text Available Blending Nomex® with cotton improves its affordability and serviceability. Because cotton is a highly flammable fiber, Nomex®/cotton blend fabrics containing more than 20% cotton require flame-retardant treatment. In this research, combination of a hydroxyl functional organophosphorus oligmer (HFPO and 1,2,3,4-butanetetracarboxylic acid (BTCA was used for flame retardant finishing of the 65/35 Nomex®/cotton blend woven fabric. The system contains HFPO as a flame retardant, BTCA as a bonding agent, and triethenolamine (TEA as a reactive additive used to enhance the performance of HFPO/BTCA. Addition of TEA improves the hydrolysis resistance of the HFPO/BTCA crosslinked polymeric network on the blend fabric. Additionally, TEA enhances HFPO’s flame retardant performance by reducing formation of calcium salts and also by providing synergistic nitrogen to the treated blend fabric. The Nomex®/cotton blend fabric treated with the HFPO/BTCA/TEA system shows high flame resistance and high laundering durability at a relatively low HFPO concentration of 8% (w/w. The heat release properties of the treated Nomex®/cotton blend fabric were measured using microscale combustion calorimetry. The functions of BTCA; HFPO and TEA on the Nomex®/cotton blend fabric were elucidated based on the heat release properties, char formation, and fire performance of the treated blend fabric.

  9. Determination of Carbamate and Organophosphorus Pesticides in Vegetable Samples and the Efficiency of Gamma-Radiation in Their Removal

    Directory of Open Access Journals (Sweden)

    Muhammed Alamgir Zaman Chowdhury

    2014-01-01

    Full Text Available In the present study, the residual pesticide levels were determined in eggplants (Solanum melongena (n=16, purchased from four different markets in Dhaka, Bangladesh. The carbamate and organophosphorus pesticide residual levels were determined by high performance liquid chromatography (HPLC, and the efficiency of gamma radiation on pesticide removal in three different types of vegetables was also studied. Many (50% of the samples contained pesticides, and three samples had residual levels above the maximum residue levels determined by the World Health Organisation. Three carbamates (carbaryl, carbofuran, and pirimicarb and six organophosphates (phenthoate, diazinon, parathion, dimethoate, phosphamidon, and pirimiphos-methyl were detected in eggplant samples; the highest carbofuran level detected was 1.86 mg/kg, while phenthoate was detected at 0.311 mg/kg. Gamma radiation decreased pesticide levels proportionately with increasing radiation doses. Diazinon, chlorpyrifos, and phosphamidon were reduced by 40–48%, 35–43%, and 30–45%, respectively, when a radiation strength of 0.5 kGy was utilized. However, when the radiation dose was increased to 1.0 kGy, the levels of the pesticides were reduced to 85–90%, 80–91%, and 90–95%, respectively. In summary, our study revealed that pesticide residues are present at high amounts in vegetable samples and that gamma radiation at 1.0 kGy can remove 80–95% of some pesticides.

  10. Detection of residual organochlorine and organophosphorus pesticides in agricultural soil in Rio Verde region of San Luis Potosi, Mexico.

    Science.gov (United States)

    Velasco, Antonio; Hernández, Sergio; Ramírez, Martha; Ortíz, Irmene

    2014-01-01

    Organochlorine pesticides were intensively used in Mexico from 1950 until their ban and restriction in 1991. However, the presence of these compounds is commonly reported in many regions of the country. The aim of the present study was to identify and quantify residual organochlorine and organophosphorus pesticides in agricultural soil in Rio Verde region, San Luis Potosi state, which has been identified as possibly polluted by pesticides. Composed samples from 24 zones covering an area of approximately 5,440 ha were analyzed. The most frequently found pesticides were p,p'-DDT followed by ,p,p'-DDE, heptachlor, endosulfan and γ-HCH whose frequency rates were 100, 91, 83 and 54%, respectively. The concentration of p,p'-DDT in the crops grown in these soils was in the following order: chili > maize > tomato > alfalfa. The results obtained in this study show that p,p'-DDT values are lower or similar to those found in other agricultural regions of Mexico. Methyl and ethyl parathion were the most frequent organophosphate pesticide detected in 100% and 62.5% of the samples with average concentrations of 25.20 and 47.48 μg kg(-1), respectively. More research is needed to establish the background levels of pesticides in agricultural soils and their potential ecological and human health effects in this region.

  11. Matrix solid-phase dispersion extraction of organophosphorus pesticide using SiO2-poly(N-vinylimidazole)

    International Nuclear Information System (INIS)

    Gutiérrez-Solís, M C; Muñoz-Rodríguez, D; Carrera-Figueiras, C; Ávila-Ortega, A; Medina-Peralta, S

    2013-01-01

    A sorbent material based on silica particles modified with poly(N-vinylimidazole) (SiO 2 -PVI) has been evaluated for the treatment of samples by matrix solid-phase dispersion (MSPD). The extraction of four organophosphorus pesticides was done from a spiked tomato and the extracts were analyzed by gas chromatography coupled to mass spectrometry. Six elution solvents were evaluated and acetone was selected due to better recovery of the four pesticides and low background signal in the chromatograms. A factorial design 2 4 was used for selection of extraction conditions. The factors were contact time, acetone volume, treatment (with or without freeze-drying) and adsorbent (SiO 2 or SiO 2 -PVI). The best recoveries were obtained using 15 minutes of contact, 2 mL of solvent and sorbent without freeze-drying. The recoveries were between 60 and 83% for SiO 2 -PVI in spiked tomato with 0.2 and 0.8μg/g.

  12. De novo amplification within a silent human cholinesterase gene in a family subjected to prolonged exposure to organophosphorus insecticides

    International Nuclear Information System (INIS)

    Prody, C.A.; Dreyfus, P.; Soreq, H.; Zamir, R.; Zakut, H.

    1989-01-01

    A 100-fold DNA amplification in the CHE gene, coding for serum butyrylcholinesterase (BtChoEase), was found in a farmer expressing silent CHE phenotype. Individuals homozygous for this gene display a defective serum BtChoEase and are particularly vulnerable to poisoning by agricultural organophosphorus insecticides, to which all members of this family had long been exposed. DNA blot hybridization with regional BtChoEase cDNA probes suggested that the amplification was most intense in regions encoding central sequences within BtChoEase cDNA, whereas distal sequences were amplified to a much lower extent. This is in agreement with the onion skin model, based on amplification of genes in cultured cells and primary tumors. The amplification was absent in the grandparents but present at the same extent in one of their sons and in a grandson, with similar DNA blot hybridization patterns. In situ hybridization experiments localized the amplified sequences to the long arm of chromosome 3, close to the site where the authors previously mapped the CHE gene. Altogether, these observations suggest that the initial amplification event occurred early in embryogenesis, spermatogenesis, or oogenesis, where the CHE gene is intensely active and where cholinergic functioning was indicated to be physiologically necessary. These findings demonstrate a de novo amplification in apparently healthy individuals within an autosomal gene producing a target protein to an inhibitor

  13. Molecular characterization of the amplified carboxylesterase gene associated with organophosphorus insecticide resistance in the brown planthopper, Nilaparvata lugens.

    Science.gov (United States)

    Small, G J; Hemingway, J

    2000-12-01

    Widespread resistance to organophosphorus insecticides (OPs) in Nilaparvata lugens is associated with elevation of carboxylesterase activity. A cDNA encoding a carboxylesterase, Nl-EST1, has been isolated from an OP-resistant Sri Lankan strain of N. lugens. The full-length cDNA codes for a 547-amino acid protein with high homology to other esterases/lipases. Nl-EST1 has an N-terminal hydrophobic signal peptide sequence of 24 amino acids which suggests that the mature protein is secreted from cells expressing it. The nucleotide sequence of the homologue of Nl-EST1 in an OP-susceptible, low esterase Sri Lankan strain of N. lugens is identical to Nl-EST1. Southern analysis of genomic DNA from the Sri Lankan OP-resistant and susceptible strains suggests that Nl-EST1 is amplified in the resistant strain. Therefore, resistance to OPs in the Sri Lankan strain is through amplification of a gene identical to that found in the susceptible strain.

  14. Development of a passive air sampler to measure airborne organophosphorus pesticides and oxygen analogs in an agricultural community.

    Science.gov (United States)

    Armstrong, Jenna L; Yost, Michael G; Fenske, Richard A

    2014-09-01

    Organophosphorus pesticides are some of the most widely used insecticides in the US, and spray drift may result in human exposures. We investigate sampling methodologies using the polyurethane foam passive air sampling device to measure cumulative monthly airborne concentrations of OP pesticides chlorpyrifos, azinphos-methyl, and oxygen analogs. Passive sampling rates (m(3)d(-1)) were determined using calculations using chemical properties, loss of depuration compounds, and calibration with side-by-side active air sampling in a dynamic laboratory exposure chamber and in the field. The effects of temperature, relative humidity, and wind velocity on outdoor sampling rates were examined at 23 sites in Yakima Valley, Washington. Indoor sampling rates were significantly lower than outdoors. Outdoor rates significantly increased with average wind velocity, with high rates (>4m(3)d(-1)) observed above 8ms(-1). In exposure chamber studies, very little oxygen analog was observed on the PUF-PAS, yet substantial amounts chlorpyrifos-oxon and azinphos methyl oxon were measured in outdoor samples. PUF-PAS is a practical and useful alternative to AAS because it results in little artificial transformation to the oxygen analog during sampling, it provides cumulative exposure estimates, and the measured sampling rates were comparable to rates for other SVOCs. It is ideal for community based participatory research due to low subject burden and simple deployment in remote areas. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Innovative approach for the electrochemical detection of non-electroactive organophosphorus pesticides using oxime as electroactive probe

    International Nuclear Information System (INIS)

    Dong, Jing; Hou, Juying; Jiang, Jianxia; Ai, Shiyun

    2015-01-01

    Highlights: • Novel approach for electrochemical detection of non-electroactive OPs was proposed. • PAM was used as electroactive probe for the first time. • The detection system displayed high sensitivity and promptness. • The developed sensor was used in real samples with satisfactory results. - Abstract: An innovative approach for sensitive and simple electrochemical detection of non-electroactive organophosphorus pesticides (OPs) was described in this report. The novel strategy emphasized the fabrication of an oxime-based sensor via attaching pralidoxime (PAM) on graphene quantum dots (GQDs) modified glassy carbon electrode. The introduction of GQDs significantly increased the effective electrode area, and then enlarged the immobilization quantity of PAM. Thus, the oxidation current of PAM was obviously increased. Relying on the nucleophilic substitution reaction between oxime and OPs, fenthion was detected using PAM as the electroactive probe. Under optimum conditions, the difference of oxidation current of PAM was proportional to fenthion concentration over the range from 1.0 × 10 −11 M to 5.0 × 10 −7 M with a detection limit of 6.8 × 10 −12 M (S/N = 3). Moreover, the favorable detection performance in water and soil samples heralded the promising applications in on-site OPs detection

  16. Application of Box-Behnken design for the removal of two organophosphorus pesticides by used Tea leaves

    Science.gov (United States)

    Albanis, Triantafyllos; Valileios, Sakkas; Islam, Azharul M.

    2016-04-01

    Removal of two organophosphorus pesticides bromophos methyl [BM: O, O- dimethyl - O - (2, 5-dichloro -4 bromophenyl) phosphorothioate] and quinalphos [QP: O, O-diethyl O-2-quinoxalinyl phosphorothioate] on used tea leaves were studied by batch equilibration method. Adsorption isotherms were conformed well to Langmuir for quinalphos and Freundlich equation for bromophos methyl. The kinetic data fitted well by the pseudo second order model for both pesticides. Box-Behnken design was successfully employed for experimental design and analysis of results. The interactions of pH, initial concentration and adsorbent dose on two pesticides adsorption by used tea leaves were investigated by this model. The optimum pH, initial concentration and adsorbent dose with their corresponding removal efficiency were found to be 7.88, 11.94 mg L-1, 0.37g and 100% for bromophos methyl respectively, for quinalphos 8.72, 6.44 mg L-1, 0.39g and 93.98% respectively. Keywords: Box-Behnken; quinalphos; bromophos methyl; Kinetics; used tea leaves

  17. RESEARCH ON ENVIRONMENTAL CONTAMINATION IN RAW MILK IN TURIN DEPARTEMENT : HEAVY METALS, P.C.B, ORGANOCHLORINE AND ORGANOPHOSPHORUS PESTICIDES – YEARS 2005 – 2008

    Directory of Open Access Journals (Sweden)

    S. Cavallera

    2013-02-01

    Full Text Available In the period between 2005 and 2008 was carried out a survey on 252 samples of raw bovine milk collected in Turin departement to certain levels of contamination by heavy metals (Cd, Cr, Fe, Hg, Pb, Zn, PCB and organophosphorus and organochlorine pesticides. These results argue that the levels of heavy metals, PCB and pesticides are well below what is expected by the European legislation and that the situation is under control and that raw milk meets the hygiene requirements for human health.

  18. Recovery evaluation of organophosphorus pesticides from bee pollen by matrix solid-phase dispersion extraction using sorbents based on silica and titania

    International Nuclear Information System (INIS)

    Torres-Perea, C; Muñoz-Rodríguez, D; Carrera-Figueiras, C; Medina-Peralta, S; Moguel-Ordóñez, Y B

    2013-01-01

    This work focused on the evaluation of the recovery of organophosphorus pesticides from bee pollen after matrix solid phase-dispersion extraction (MSPD). Materials based on silica, titania and titania modified with polivylnylimidazole or polyestirene were used as adsorbents for the extraction of pesticides. Small amounts of fortified pollen (0.1 g, at 1 micro-g/g of pesticides), adsorbent (0.4 g) and solvent elution (1 mL de acetonitrile – ACN) were used in the extractions. For recovery evaluation, pollen extracts were analyzed by gas chromatography coupled with mass spectrometry.

  19. [COMPARATIVE SENSITIVITY OF CHOLINESTERASES IN VERTEBRATES AND INVERTEBRATES TO HIGHLY SPECIFIC ORGANOPHOSPHORUS INHIBITORS DIISOPROPYL FLUOROPHOSPHATE (DFP) AND (2-ETHOXYMETHYL PHOSPHORYL THIOETHYL) ETHYL (METHYL) SULPHONIUM SULPHOMETHYLAT (GD-42)].

    Science.gov (United States)

    Basova, N E; Kormilitsyn, B N; Perchenok, A Yu; Rozengart, E V; Saakov, V S; Suvorov, A A

    2015-01-01

    The review presents data on comparative reactivity of 68 cholinesterase preparation from various organs and tissues in a number of vertebrates and invertebrates based on sensitivity to two highly specific and most studied organophosphorus inhibitors--diisopropyl fluorophosphates (DFP) and (2-ethoxymethyl phosphoryl thioethyl) ethyl (methyl) sulphonium sulphomethylat (GD-42). Analysis of these data suggests a great diversity in enzymologic characteristics of cholinesterase preparation in representatives of vertebrates and invertebrates, this variety observed even for closely related enzymes in animals of almost the same level of development.

  20. Exposure assessment of organophosphorus and organobromine flame retardants via indoor dust from elementary schools and domestic houses.

    Science.gov (United States)

    Mizouchi, Shigekazu; Ichiba, Masayoshi; Takigami, Hidetaka; Kajiwara, Natsuko; Takamuku, Toshiyuki; Miyajima, Toru; Kodama, Hiroki; Someya, Takashi; Ueno, Daisuke

    2015-03-01

    To assess the exposure of flame retardants (FRs) for school-children, organophosphorus flame retardants and plasticizers (PFRs) and organobromine flame retardants (BFRs) were determined in the indoor dust samples collected from elementary schools and domestic houses in Japan in 2009 and 2010. PFRs were detected in all the dust samples analyzed and the highest concentration of total PFRs was thousand-fold higher than that of BFRs. Among the PFRs, tris(butoxyethyl)phosphate (TBOEP) showed the highest concentration with a median (med.) of 270,000 ng g(-1) dry weight (3700-5,500,000 ng g(-1) dry weight), followed by tris(methylphenyl)phosphate (TMPPs)>triphenyl phosphate (TPHP)=tris(1,3-dichloro-2-propyl)phosphate (TDCIPP)=tris(2-chloroisopropyl)phosphate (TCIPP)=tris(2chloroethyl)phosphate (TCEP)>ethylhexyl diphenyl phosphate (EHDPP). Significantly higher concentrations of TBOEP, tri-n-butyl phosphate (TNBP), TPHP, TMPPs, and total-PFRs were found in dust samples from elementary schools than from domestic houses. It might be due to that higher concentrations of TBOEP (as leveling agent) were detected from the floor polisher/wax products collected in those elementary schools. On the other hand, significantly higher concentrations of TCEP, TCIPPs, and total chloroalkyl-PFRs were found in domestic houses than in elementary schools. Exposure assessments of PFRs via indoor dust from elementary schools and domestic houses were conducted by calculating the hazard quotient (HQ). Among PFRs, HQs for TBOEP exceeded 1 (higher than reference dose: RfD) and its highest value was 1.9. To reduce the intake of TBOEP by school-children, it is recommended that the use of floor polisher/wax containing TBOEP be reduced in schools. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Determination of organophosphorus pesticides by dispersive liquid-liquid micro extraction coupled with gas chromatography-electron capture detection

    International Nuclear Information System (INIS)

    Mohd Marsin Sanagi; Siti Umairah Mokhtar; Mazidatul Akmam Miskam; Wan Aini Wan Ibrahim

    2011-01-01

    A simple, rapid and sensitive method termed as dispersive liquid-liquid micro extraction (DLLME) combined with gas chromatography-electron capture detector (GC-ECD) was developed for the determination of selected organophosphorus pesticides (OPPs) namely chloropyrifos, dimethoate and diazinon in water sample. In this method, a mixture of carbon disulfide, CS 2 (extraction solvent) and methanol (disperser solvent) was rapidly injected using syringe into the 5.00 mL water sample to form a cloudy solution where the OPPs were extracted into the fine droplets of extraction solvent. Upon centrifugation for 3 min at 3500 rpm, the fine droplets were sedimented at the bottom of the centrifuge tube. Sedimented phase (1 μL) was injected into the GC-ECD for separation and determination of OPPs. Important extraction parameters, such as type of disperser solvent, volume of extraction solvent and volume of disperser solvent were investigated. The optimized conditions for DLLME of the selected OPPs were methanol as disperser solvent, 30 μL of extraction solvent (CS 2 ) and 1.0 mL of disperser solvent (methanol). Under the optimum extraction conditions, the method showed good linearity in the range of 0.1 to 1.0 μg/ mL with correlation coefficient (r 2 ), in the range of 0.9976 to 0.9994 and low limits of detection (LOD) between 0.047 and 0.201 μg/ mL. The proposed method provided acceptable recoveries (72.67- 144 %) with good RSDs ranging from 2.74 % to 7.48 %. This method was successfully applied to the determination of OPPs in water samples obtained from a golf course and chloropyrifos and diazinon were detected at concentration 0.18 μg/ mL and 0.07 μg/ mL, respectively. (author)

  2. Galantamine counteracts development of learning impairment in guinea pigs exposed to the organophosphorus poison soman: Clinical significance

    Science.gov (United States)

    Mamczarz, Jacek; Kulkarni, Girish S.; Pereira, Edna F. R.; Albuquerque, Edson X.

    2017-01-01

    Galantamine, a drug used to treat Alzheimer’s disease, protects guinea pigs against the acute toxicity and lethality of organophosphorus (OP) compounds, including soman. Here, we tested the hypothesis that a single exposure of guinea pigs to 1xLD50 soman triggers cognitive impairments that can be counteracted by galantamine. Thus, animals were injected intramuscularly with saline (0.5 ml/kg) or galantamine (8 mg/kg) and 30 min later injected subcutaneously with soman (26.3 µg/kg) or saline. Cognitive performance was analyzed in the Morris water maze (MWM) four days or three months after the soman challenge. Fifty percent of the saline-injected animals that were challenged with soman survived with mild-to-moderate signs of acute toxicity that subsided within a few hours. These animals showed no learning impairment and no memory retention deficit, when training in the MWM started four days post-soman challenge. In contrast, animals presented significant learning impairment when testing started three months post-challenge. Though the magnitude of the impairment correlated with the severity of the acute toxicity, animals that presented no or only mild signs of toxicity were also learning impaired. All guinea pigs that were treated with galantamine survived the soman challenge with no signs of acute toxicity and learned the MWM task as control animals, regardless of when testing began. Galantamine also prevented memory extinction in both saline-and soman-challenged animals. In conclusion, learning impairment develops months after a single exposure to 1xLD50 soman, and galantamine prevents both the acute toxicity and the delayed cognitive deficits triggered by this OP poison. PMID:21784098

  3. An Innovative Rapid Method for Analysis of 10 Organophosphorus Pesticide Residues in Wheat by HS-SPME-GC-FPD/MSD.

    Science.gov (United States)

    Du, Xin; Ren, YongLin; Beckett, Stephen J

    2016-01-01

    The rapid detection of pesticide residues in wheat has become a top food security priority. A solvent-free headspace solid-phase microextraction (HS-SPME) has been evaluated for rapid screening of organophosphorus pesticide (OPP) residues in wheat with high sensitivity. Individual wheat samples (1.7 g), spiked with 10 OPPs, were placed in a 4 mL sealed amber glass vial and heated at 60°C for 45 min. During this time, the OPP residues were extracted with a 50 μm/30 μm divinylbenzene (DVB)/carboxen (CAR)/plasma desorption mass spectroscopy polydimethylsiloxane (PDMS) fiber from the headspace above the sample. The fiber was then removed and injected into the GC injection port at 250°C for desorption of the extracted chemicals. The multiple residues were identified by a GC mass spectrometer detector (GC-MSD) and quantified with a GC flame photometric detector (GC-FPD). Seven spiked levels of 10 OPPs on wheat were analyzed. The GC responses for a 50 μm/30 μm DVB/CAR/PDMS fiber increased with increasing spiking levels, yielding significant (R(2) > 0.98) linear regressions. The lowest LODs of the multiple pesticide standards were evaluated under the conditions of the validation study in a range of levels from 0 (control) to 100 ng of pesticide residue per g of wheat that separated on a low-polar GC capillary column (Agilent DB-35UI). The results of the HS-SPME method were compared with the QuEChERS AOAC 2007.01 method and they showed several advantages over the latter. These included improved sensitivity, selectivity, and simplicity.

  4. Method development and validation for the simultaneous determination of organochlorine and organophosphorus pesticides in a complex sediment matrix.

    Science.gov (United States)

    Alcántara-Concepción, Victor; Cram, Silke; Gibson, Richard; Ponce de León, Claudia; Mazari-Hiriart, Marisa

    2013-01-01

    The Xochimilco area in the southeastern part of Mexico City has a variety of socioeconomic activities, such as periurban agriculture, which is of great importance in the Mexico City metropolitan area. Pesticides are used extensively, some being legal, mostly chlorpyrifos and malathion, and some illegal, mostly DDT. Sediments are a common sink for pesticides in aquatic systems near agricultural areas, and Xochimilco sediments have a complex composition with high contents of organic matter and clay that are ideal adsorption sites for organochlorine (OC) and organophosphorus (OP) pesticides. Therefore, it is important to have a quick, affordable, and reliable method to determine these pesticides. Conventional methods for the determination of OC and OP pesticides are long, laborious, and costly owing to the high volume of solvents and adsorbents. The present study developed and validated a method for determining 18 OC and five OP pesticides in sediments with high organic and clay contents. In contrast with other methods described in the literature, this method allows isolation of the 23 pesticides with a 12 min microwave-assisted extraction (MAE) and one-step cleanup of pesticides. The method developed is a simpler, time-saving procedure that uses only 3.5 g of dry sediment. The use of MAE eliminates excessive handling and the possible loss of analytes. It was shown that the use of LC-Si cartridges with hexane-ethyl acetate (75+25, v/v) in the cleanup procedure recovered all pesticides with rates between 70 and 120%. The validation parameters demonstrated good performance of the method, with intermediate precision ranging from 7.3 to 17.0%, HorRat indexes all below 0.5, and tests of accuracy with the 23 pesticides at three concentration levels demonstrating recoveries ranging from 74 to 114% and RSDs from 3.3 to 12.7%.

  5. A sensitive LC-MS/MS method for measurement of organophosphorus pesticides and their oxygen analogs in air sampling matrices.

    Science.gov (United States)

    Armstrong, Jenna L; Dills, Russell L; Yu, Jianbo; Yost, Michael G; Fenske, Richard A

    2014-01-01

    A rapid liquid chromatography tandem mass spectrometry (LC-MS/MS) method has been developed for determination of levels of the organophosphorus (OP) pesticides chlorpyrifos (CPF), azinphos methyl (AZM), and their oxygen analogs chlorpyrifos-oxon (CPF-O) and azinphos methyl-oxon (AZM-O) on common active air sampling matrices. XAD-2 resin and polyurethane foam (PUF) matrices were extracted with acetonitrile containing stable-isotope labeled internal standards (ISTD). Analysis was accomplished in Multiple Reaction Monitoring (MRM) mode, and analytes in unknown samples were identified by retention time (±0.1 min) and qualifier ratio (±30% absolute) as compared to the mean of calibrants. For all compounds, calibration linearity correlation coefficients were ≥0.996. Limits of detection (LOD) ranged from 0.15-1.1 ng/sample for CPF, CPF-O, AZM, and AZM-O on active sampling matrices. Spiked fortification recoveries were 78-113% from XAD-2 active air sampling tubes and 71-108% from PUF active air sampling tubes. Storage stability tests also yielded recoveries ranging from 74-94% after time periods ranging from 2-10 months. The results demonstrate that LC-MS/MS is a sensitive method for determining these compounds from two different matrices at the low concentrations that can result from spray drift and long range transport in non-target areas following agricultural applications. In an inter-laboratory comparison, the limit of quantification (LOQ) for LC-MS/MS was 100 times lower than a typical gas chromatography-mass spectrometry (GC-MS) method.

  6. Organophosphorus pesticide and ester analysis by using comprehensive two-dimensional gas chromatography with flame photometric detection.

    Science.gov (United States)

    Liu, Xiangping; Li, Dengkun; Li, Jiequan; Rose, Gavin; Marriott, Philip J

    2013-12-15

    Thirty-seven phosphorus (P)-containing compounds comprising organophosphorus pesticides and organophosphate esters were analyzed by using comprehensive two-dimensional gas chromatography with flame photometric detection in P mode (GC × GC-FPD(P)), with a non-polar/moderately polar column set. A suitable modulation temperature and period was chosen based on experimental observation. A number of co-eluting peak pairs on the (1)D column were well separated in 2D space. Excellent FPD(P) detection selectivity, responding to compounds containing the P atom, produces clear 2D GC × GC plots with little interference from complex hydrocarbon matrices. Limits of detection (LOD) were within the range of 0.0021-0.048 μmol L(-1), and linear calibration correlation coefficients (R(2)) for all 37 P-compounds were at least 0.998. The P-compounds were spiked in 2% diesel and good reproducibility for their response areas and retention times was obtained. Spiked recoveries were 88%-157% for 5 μg L(-1) and 80%-138% for 10 μg L(-1) spiked levels. Both (1)tR and (2)tR shifts were noted when the content of diesel was in excess of 5% in the matrix. Soil samples were analyzed by using the developed method; some P-compounds were positively detected. In general, this study shows that GC × GC-FPD(P) is an accurate, sensitive and simple method for P-compound analysis in complicated environmental samples. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Synthesis and application of molecularly imprinted polymers for the selective extraction of organophosphorus pesticides from vegetable oils.

    Science.gov (United States)

    Boulanouar, Sara; Combès, Audrey; Mezzache, Sakina; Pichon, Valérie

    2017-09-01

    The increasing use of pesticides in agriculture causes environmental issues and possible serious health risks to humans and animals. Their determination at trace concentrations in vegetable oils constitutes a significant analytical challenge. Therefore, their analysis often requires both an extraction and a purification step prior to separation with liquid chromatography (LC) and mass spectrometry (MS) detection. This work aimed at developing sorbents that are able to selectively extract from vegetable oil samples several organophosphorus (OPs) pesticides presenting a wide range of physico-chemical properties. Therefore, different conditions were screened to prepare molecularly imprinted polymers (MIPs) by a non-covalent approach. The selectivity of the resulting polymers was evaluated by studying the OPs retention in pure media on both MIPs and non-imprinted polymers (NIP) used as control. The most promising MIP sorbent was obtained using monocrotophos (MCP) as the template, methacrylic acid (MAA) as the monomer and ethylene glycol dimethacrylate (EGDMA) as the cross-linker with a molar ratio of 1/4/20 respectively. The repeatability of the extraction procedure and of the synthesis procedure was demonstrated in pure media. The capacity of this MIP was 1mg/g for malathion. This MIP was also able to selectively extract three OPs from almond oil by applying the optimized SPE procedure. Recoveries were between 73 and 99% with SD values between 4 and 6% in this oil sample. The calculated LOQs (between 0.3 and 2μg/kg) in almond seeds with a SD between 0.1 and 0.4μg/kg were lower than the Maximum Residue Levels (MRLs) established for the corresponding compounds in almond seed. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Multiwalled carbon nanotubes as solid-phase extraction materials for the gas chromatographic determination of organophosphorus pesticides in waters.

    Science.gov (United States)

    Ravelo-Pérez, Lidia M; Hernández-Borges, Javier; Angel Rodríguez-Delgado, Miguel

    2008-10-01

    In the present work, a GC method with nitrogen-phosphorus detection (NPD) was developed for the simultaneous determination of eight organophosphorus pesticide (OPP) residues (i.e., ethoprofos, diazinon, chlorpyrifos-methyl, fenitrothion, malathion, chlorpyrifos, fenamiphos, and buprofezin) in water samples. Preconcentration of the water samples was carried out using an SPE procedure with multiwalled carbon nanotubes (MWCNTs) of 10-15 nm od, 2-6 nm id, and 0.1-10 microm length as stationary phase. Extraction parameters, such as the amount of MWCNTs, sample volume, pH, and type and amount of the eluent were optimized. The most favorable conditions were as follows: 40 mg MWCNTs, 800 mL water, pH 6.0, and 20 mL dichloromethane, respectively. The MWCNTs-SPE-GC-NPD method was applied to the determination of these pesticides in real water samples: mineral and ground water as well as run-off water from an agricultural area collected shortly before opening out onto the sea. A recovery study was developed with five consecutive extractions of the three types of water spiked at three concentration levels (n = 15). Mean recovery values were in the range of 75-116% for mineral water (RSD water (RSD waters (RSDs waters, RSDs waters). The proposed method was also applied to the analysis of six water samples (two of each type: mineral, ground, and run-off waters) in which no residues of the selected pesticides were found. Results show that the MWCNTs used in this work have a high adsorbability of the pesticides under study. The main advantage of the use of these MWCNTs is their low cost when compared with those MWCNTs previously used in the literature and with conventional SPE cartridges.

  9. Organophosphorus insecticides chlorpyrifos and diazinon and oxidative stress in neuronal cells in a genetic model of glutathione deficiency

    International Nuclear Information System (INIS)

    Giordano, Gennaro; Afsharinejad, Zhara; Guizzetti, Marina; Vitalone, Annabella; Kavanagh, Terrance J.; Costa, Lucio G.

    2007-01-01

    Over the past several years evidence has been accumulating from in vivo animal studies, observations in humans, and in vitro studies, that organophosphorus (OP) insecticides may induce oxidative stress. Such effects may contribute to some of the toxic manifestations of OPs, particularly upon chronic or developmental exposures. The aim of this study was to investigate the role of oxidative stress in the neurotoxicity of two commonly used OPs, chlorpyrifos (CPF) and diazinon (DZ), their oxygen analogs (CPO and DZO), and their 'inactive' metabolites (TCP and IMP), in neuronal cells from a genetic model of glutathione deficiency. Cerebellar granule neurons from wild type mice (Gclm +/+) and mice lacking the modifier subunit of glutamate cysteine ligase (Gclm -/-), the first and limiting step in the synthesis of glutathione (GSH), were utilized. The latter display very low levels of GSH and are more susceptible to the toxicity of agents that increase oxidative stress. CPO and DZO were the most cytotoxic compounds, followed by CPF and DZ, while TCP and IMP displayed lower toxicity. Toxicity was significantly higher (10- to 25-fold) in neurons from Gclm (-/-) mice, and was antagonized by various antioxidants. Depletion of GSH from Gclm (+/+) neurons significantly increased their sensitivity to OP toxicity. OPs increased intracellular levels of reactive oxygen species and lipid peroxidation and in both cases the effects were greater in neurons from Gclm (-/-) mice. OPs did not alter intracellular levels of GSH, but significantly increased those of oxidized glutathione (GSSG). Cytotoxicity was not antagonized by cholinergic antagonists, but was decreased by the calcium chelator BAPTA-AM. These studies indicate that cytotoxicity of OPs involves generation of reactive oxygen species and is modulated by intracellular GSH, and suggest that it may involve disturbances in intracellular homeostasis of calcium

  10. Organophosphorus pesticide residues in vegetables from farms, markets, and a supermarket around Kwan Phayao Lake of Northern Thailand.

    Science.gov (United States)

    Sapbamrer, Ratana; Hongsibsong, Surat

    2014-07-01

    This study investigated organophosphorus (OP) residues in vegetables from 27 farms, 106 markets, and 1 supermarket around Kwan Phayao Lake, Northern Thailand, between August and September 2013. Types of vegetables sampled were all vegetables cultivated or sold around the study site. The most common OP pesticides detected in farm samples were chlorpyrifos (50 %), malathion (31.8 %), monocrotophos (31.8 %), diazinon (13.6 %), omethoate (13.6 %), and dicrotophos (9.1 %). The most common OP pesticides detected in market samples were chlorpyrifos (33.9 %), diazinon (18.6 %), parathion-methyl (3.4 %), profenofos (3.4 %), primiphos-ethyl (3.4 %), and fenitrothion (1.7 %). The OP pesticides detected in supermarket samples were chlorpyrifos (33.3 %), and diazinon (66.7 %). Among the compounds detected, chlorpyrifos was detected in most of the vegetable samples from all sources. The highest chlorpyrifos level in farm samples were found in lemon balm (2.423 mg/kg) followed by Vietnamese coriander (0.835 mg/kg), and cowpea (0.027 mg/kg). The highest level in markets samples were found in garlic (7.785 mg/kg) followed by Chinese cabbage (2.864 mg/kg) and Vietnamese coriander (1.308 mg/kg). Residues from supermarket samples were found only in parsley (0.027 mg/kg). The findings showed that 16 samples (59.3 %) from farms and 14 samples (13.2 %) from markets contained OP residues at or above the maximum residue limits established by the European Union. It is concluded that awareness, safety education, and strict regulation of pesticide use are necessary.

  11. Proton conducting membranes prepared by incorporation of organophosphorus acids into alcohol barrier polymers for direct methanol fuel cells

    Science.gov (United States)

    Jiang, Zhongyi; Zheng, Xiaohong; Wu, Hong; Pan, Fusheng

    A novel type of DMFC membrane was developed via incorporation of organophosphorus acids (OPAs) into alcohol barrier materials (polyvinyl alcohol/chitosan, PVA/CS) to simultaneously acquire high proton conductivity and low methanol permeability. Three kinds of OPAs including amino trimethylene phosphonic acid (ATMP), ethylene diamine tetra(methylene phosphonic acid) (EDTMP) and hexamethylene diamine tetra(methylene phosphonic acid) (HDTMP), with different molecular structure and phosphonic acid groups content were added into PVA/CS blends and served the dual functions as proton conductor as well as crosslinker. The as-prepared OPA-doped PVA/CS membranes exhibited remarkably enhanced proton conducting ability, 2-4 times higher than that of the pristine PVA/CS membrane, comparable with that for Nafion ®117 membrane (5.04 × 10 -2 S cm -1). The highest proton conductivities 3.58 × 10 -2, 3.51 × 10 -2 and 2.61 × 10 -2 S cm -1 for ATMP-, EDTMP- and HDTMP-doped membranes, respectively were all achieved at highest initial OPA doping content (23.1 wt.%) at room temperature. The EDTMP-doped PVA/CS membrane with an acid content of 13.9 wt.% showed the lowest methanol permeability of 2.32 × 10 -7 cm 2 s -1 which was 16 times lower than that of Nafion ®117 membrane. In addition, the thermal stability and oxidative durability were both significantly improved by the incorporation of OPAs in comparison with pristine PVA/CS membranes.

  12. Proton conducting membranes prepared by incorporation of organophosphorus acids into alcohol barrier polymers for direct methanol fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Zhongyi; Zheng, Xiaohong; Wu, Hong; Pan, Fusheng [Key Laboratory for Green Chemical Technology, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China)

    2008-10-15

    A novel type of DMFC membrane was developed via incorporation of organophosphorus acids (OPAs) into alcohol barrier materials (polyvinyl alcohol/chitosan, PVA/CS) to simultaneously acquire high proton conductivity and low methanol permeability. Three kinds of OPAs including amino trimethylene phosphonic acid (ATMP), ethylene diamine tetra(methylene phosphonic acid) (EDTMP) and hexamethylene diamine tetra(methylene phosphonic acid) (HDTMP), with different molecular structure and phosphonic acid groups content were added into PVA/CS blends and served the dual functions as proton conductor as well as crosslinker. The as-prepared OPA-doped PVA/CS membranes exhibited remarkably enhanced proton conducting ability, 2-4 times higher than that of the pristine PVA/CS membrane, comparable with that for Nafion {sup registered} 117 membrane (5.04 x 10{sup -2} S cm{sup -1}). The highest proton conductivities 3.58 x 10{sup -2}, 3.51 x 10{sup -2} and 2.61 x 10{sup -2} S cm{sup -1} for ATMP-, EDTMP- and HDTMP-doped membranes, respectively were all achieved at highest initial OPA doping content (23.1 wt.%) at room temperature. The EDTMP-doped PVA/CS membrane with an acid content of 13.9 wt.% showed the lowest methanol permeability of 2.32 x 10{sup -7} cm{sup 2} s{sup -1} which was 16 times lower than that of Nafion {sup registered} 117 membrane. In addition, the thermal stability and oxidative durability were both significantly improved by the incorporation of OPAs in comparison with pristine PVA/CS membranes. (author)

  13. Biodegradation and bioremediation potential of diazinon-degrading Serratia marcescens to remove other organophosphorus pesticides from soils.

    Science.gov (United States)

    Cycoń, Mariusz; Żmijowska, Agnieszka; Wójcik, Marcin; Piotrowska-Seget, Zofia

    2013-03-15

    The ability of diazinon-degrading Serratia marcescens to remove organophosphorus pesticides (OPPs), i.e. chlorpyrifos (CP), fenitrothion (FT), and parathion (PT) was studied in a mineral salt medium (MSM) and in three soils of different characteristics. This strain was capable of using all insecticides at concentration of 50 mg/l as the only carbon source when grown in MSM, and 58.9%, 70.5%, and 82.5% of the initial dosage of CP, FT, and PT, respectively was degraded within 14 days. The biodegradation experiment showed that autochthonous microflora in all soils was characterized by a degradation potential of all tested OPPs; however, the initial lag phases for degradation of CP and FT, especially in sandy soil, were observed. During the 42-day experiment, 45.3%, 61.4% and 72.5% of the initial dose of CP, FT, and PT, respectively, was removed in sandy soil whereas the degradation of CP, FT, and PT in the same period, in sandy loam and silty soils reached 61.4%, 79.7% and 64.2%, and 68.9%, 81.0% and 63.6%, respectively. S. marcescens introduced into sterile soils showed a higher degradation potential (5-13%) for OPPs removal than those observed in non-sterile soil with naturally occurring attenuation. Inoculation of non-sterile soils with S. marcescens enhanced the disappearance rates of all insecticides, and DT50 for CP, FT, and PT was reduced by 20.7, 11.3 and 13.0 days, and 11.9, 7.0 and 8.1 days, and 9.7, 14.5 and 12.6 days in sandy, sandy loam, and silty soils, respectively, in comparison with non-sterile soils with only indigenous microflora. This ability of S. marcescens makes it a suitable strain for bioremediation of soils contaminated with OPPs. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Inhibition, recovery and oxime-induced reactivation of muscle esterases following chlorpyrifos exposure in the earthworm Lumbricus terrestris

    International Nuclear Information System (INIS)

    Collange, B.; Wheelock, C.E.; Rault, M.; Mazzia, C.; Capowiez, Y.; Sanchez-Hernandez, J.C.

    2010-01-01

    Assessment of wildlife exposure to organophosphorus (OP) pesticides generally involves the measurement of cholinesterase (ChE) inhibition, and complementary biomarkers (or related endpoints) are rarely included. Herein, we investigated the time course inhibition and recovery of ChE and carboxylesterase (CE) activities in the earthworm Lumbricus terrestris exposed to chlorpyrifos, and the ability of oximes to reactivate the phosphorylated ChE activity. Results indicated that these esterase activities are a suitable multibiomarker scheme for monitoring OP exposure due to their high sensitivity to OP inhibition and slow recovery to full activity levels following pesticide exposure. Moreover, oximes reactivated the inhibited ChE activity of the earthworms exposed to 12 and 48 mg kg -1 chlorpyrifos during the first week following pesticide exposure. This methodology is useful for providing evidence for OP-mediated ChE inhibition in individuals with a short history of OP exposure (≤1 week); resulting a valuable approach for assessing multiple OP exposure episodes in the field. - Esterase inhibition combined with oxime reactivation methods is a suitable approach for monitoring organophosphate contamination

  15. Inhibition, recovery and oxime-induced reactivation of muscle esterases following chlorpyrifos exposure in the earthworm Lumbricus terrestris

    Energy Technology Data Exchange (ETDEWEB)

    Collange, B. [Universite d' Avignon et des Pays de Vaucluse, UMR 406 Abeilles et Environnement, Site AGROPARC, F-84914, Avignon Cede 09 (France); Wheelock, C.E. [Division of Physiological Chemistry II, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE 171 77, Stockholm (Sweden); Rault, M.; Mazzia, C. [Universite d' Avignon et des Pays de Vaucluse, UMR 406 Abeilles et Environnement, Site AGROPARC, F-84914, Avignon Cede 09 (France); Capowiez, Y. [INRA, Unite PSH, Site AGROPARC, F-84914 Avignon Cedex 09 (France); Sanchez-Hernandez, J.C., E-mail: juancarlos.sanchez@uclm.e [Laboratory of Ecotoxicology, Faculty of Environmental Science, University of Castilla-La Mancha, Avda. Carlos III s/n, 45071, Toledo (Spain)

    2010-06-15

    Assessment of wildlife exposure to organophosphorus (OP) pesticides generally involves the measurement of cholinesterase (ChE) inhibition, and complementary biomarkers (or related endpoints) are rarely included. Herein, we investigated the time course inhibition and recovery of ChE and carboxylesterase (CE) activities in the earthworm Lumbricus terrestris exposed to chlorpyrifos, and the ability of oximes to reactivate the phosphorylated ChE activity. Results indicated that these esterase activities are a suitable multibiomarker scheme for monitoring OP exposure due to their high sensitivity to OP inhibition and slow recovery to full activity levels following pesticide exposure. Moreover, oximes reactivated the inhibited ChE activity of the earthworms exposed to 12 and 48 mg kg{sup -1} chlorpyrifos during the first week following pesticide exposure. This methodology is useful for providing evidence for OP-mediated ChE inhibition in individuals with a short history of OP exposure (<=1 week); resulting a valuable approach for assessing multiple OP exposure episodes in the field. - Esterase inhibition combined with oxime reactivation methods is a suitable approach for monitoring organophosphate contamination

  16. Isolation of the opdE gene that encodes for a new hydrolase of Enterobacter sp. capable of degrading organophosphorus pesticides.

    Science.gov (United States)

    Chino-Flores, Concepción; Dantán-González, Edgar; Vázquez-Ramos, Alejandra; Tinoco-Valencia, Raunel; Díaz-Méndez, Rafael; Sánchez-Salinas, Enrique; Castrejón-Godínez, Maria Luisa; Ramos-Quintana, Fernando; Ortiz-Hernández, Maria Laura

    2012-06-01

    Microbial enzymes that can hydrolyze organophosphorus compounds have been isolated, identified and characterized from different microbial species in order to use them in biodegradation of organophosphorus compounds. We isolated a bacterial strain Cons002 from an agricultural soil bacterial consortium, which can hydrolyze methyl-parathion (MP) and other organophosphate pesticides. HPLC analysis showed that strain Cons002 is capable of degrading pesticides MP, parathion and phorate. Pulsed-field gel electrophoresis and 16S rRNA amplification were performed for strain characterization and identification, respectively, showing that the strain Cons002 is related to the genus Enterobacter sp. which has a single chromosome of 4.6 Mb and has no plasmids. Genomic library was constructed from DNA of Enterobacter sp. Cons002. A gene called opdE (Organophosphate Degradation from Enterobacter) consists of 753 bp and encodes a protein of 25 kDa, which was isolated using activity methods. This gene opdE had no similarity to any genes reported to degrade organophosphates. When kanamycin-resistance cassette was placed in the gene opdE, hydrolase activity was suppressed and Enterobacter sp. Cons002 had no growth with MP as a nutrients source.

  17. Simultaneous determination of organophosphorus pesticides in fruits and vegetables using atmospheric pressure gas chromatography quadrupole-time-of-flight mass spectrometry.

    Science.gov (United States)

    Cheng, Zhipeng; Dong, Fengshou; Xu, Jun; Liu, Xingang; Wu, Xiaohu; Chen, Zenglong; Pan, Xinglu; Gan, Jay; Zheng, Yongquan

    2017-09-15

    This paper describes the application of atmospheric pressure gas chromatography quadrupole-time-of-flight mass spectrometry for the simultaneous determination of organophosphorus pesticides in apple, pear, tomato, cucumber and cabbage. Soft ionization with atmospheric pressure ionization source was compared with traditional electron impact ionization (EI). The sensitivity of GC coupled to atmospheric pressure ionization (APGC) for all the analytes was enhanced by 1.0-8.2 times. The ionization modes with atmospheric pressure ionization source was studied by comparing the charge-transfer and proton-transfer conditions. The optimized QuEChERs method was used to pretreat the samples. The calibration curves were found linear from 10 to 1000μg/L, obtaining correlation coefficients higher than 0.9845. Satisfactory mean recovery values, in the range of 70.0-115.9%, and satisfactory precision, with all RSD r <19.7% and all RSD R values <19.5% at the three fortified concentration levels for all the fifteen OPPs. The results demonstrate the potential of APGC-QTOF-MS for routine quantitative analysis of organophosphorus pesticide in fruits and vegetables. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. [High throuput analysis of organophosphorus pesticide residues and their metabolites in animal original foods by dual gas chromatography-dual pulse flame photometric detection].

    Science.gov (United States)

    Yang, Lixin; Li, Heli; Miao, Hong; Zeng, Fangang; Li, Ruifeng; Chen, Huijing; Zhao, Yunfeng; Wu, Yongning

    2011-10-01

    A method was established for the quantitative determination of 54 organophosphorus pesticide residues and their metabolites in foods of animal origin by dual gas chromatography-dual pulse flame photometric detection. Homogenized samples were extracted with acetone and methylene chloride, and cleaned-up by gel permeation chromatography (GPC). The response of each analyte showed a good linearity with a correlation coefficient not less than 0. 99. The recovery experiments were performed by a blank sample spiked at low, medium and high fortification levels. The recoveries for beef, mutton, pork, chicken were in the range of 50. 5% -128. 1% with the relative standard deviations (n = 6) of 1. 1% -25. 5%, which demonstrated the good precision and accuracy of the present method. The limits of detection for the analytes were in the range of 0. 001 -0. 170 mg/kg, and the limits of quantification were in the range of 0. 002 -0. 455 mg/kg. Animal food samples collected from markets such as meat, liver and kidney were analyzed, and the residues of dichlorovos and disulfoton-sulfoxide were found in the some samples. The established method is sensitive and selective enough to detect organophosphorus pesticide residues in animal foods.

  19. Developmental exposure to terbutaline alters cell signaling in mature rat brain regions and augments the effects of subsequent neonatal exposure to the organophosphorus insecticide chlorpyrifos

    International Nuclear Information System (INIS)

    Meyer, Armando; Seidler, Frederic J.; Aldridge, Justin E.; Slotkin, Theodore A.

    2005-01-01

    Exposure to apparently unrelated neurotoxicants can nevertheless converge on common neurodevelopmental events. We examined the long-term effects of developmental exposure of rats to terbutaline, a β-adrenoceptor agonist used to arrest preterm labor, and the organophosphorus insecticide chlorpyrifos (CPF) separately and together. Treatments mimicked the appropriate neurodevelopmental stages for human exposures: terbutaline on postnatal days (PN) 2-5 and CPF on PN11-14, with assessments conducted on PN45. Although neither treatment affected growth or viability, each elicited alterations in CNS cell signaling mediated by adenylyl cyclase (AC), a transduction pathway shared by numerous neuronal and hormonal signals. Terbutaline altered signaling in the brainstem and cerebellum, with gender differences particularly notable in the cerebellum (enhanced AC in males, suppressed in females). By itself, CPF exposure elicited deficits in AC signaling in the midbrain, brainstem, and striatum. However, sequential exposure to terbutaline followed by CPF produced larger alterations and involved a wider spectrum of brain regions than were obtained with either agent alone. In the cerebral cortex, adverse effects of the combined treatment intensified between PN45 and PN60, suggesting that exposures alter the long-term program for development of synaptic communication, leading to alterations in AC signaling that emerge even after adolescence. These findings indicate that terbutaline, like CPF, is a developmental neurotoxicant, and reinforce the idea that its use in preterm labor may create a subpopulation that is sensitized to long-term CNS effects of organophosphorus insecticides

  20. Inhibition: Mental Control Process or Mental Resource?

    Science.gov (United States)

    Im-Bolter, Nancie; Johnson, Janice; Ling, Daphne; Pascual-Leone, Juan

    2015-01-01

    The current study tested 2 models of inhibition in 45 children with language impairment and 45 children with normally developing language; children were aged 7 to 12 years. Of interest was whether a model of inhibition as a mental-control process (i.e., executive function) or as a mental resource would more accurately reflect the relations among…

  1. Investigation of the chemical identity of soluble organophosphorus compounds found in natural waters. Research report

    International Nuclear Information System (INIS)

    Minear, R.A.

    1978-04-01

    Four algal species (Chlamydomonas reinhardtii, Chlorella pyrenoidosa, Anacystis nidulans, and Anabaena flos-aquae) were grown in batch culture on 32 P labelled media to yield dissolved organic phosphorus (DOP) compounds containing a radioactive tag. The DOP compounds of filtered culture solutions were characterized by Sephadex gel filtration and thin layer chromatography (TLC) as a function of culture age. Additional TLC of individual Sephadex fractions was conducted. Time, culture and known compounds (inositol mono- and hexaphosphate) comparisons were made. High performance liquid chromatography was used to separate inositol mono- and hexaphosphates and to compare the DOP components of one algal species (C. reinhardtii) with inositol phosphates. Combinations of alkaline bromination and Sephadex pretreatment were examined

  2. Interrelation of Glycemic Status and Neuropsychiatric Disturbances in Farmers with Organophosphorus Pesticide Toxicity.

    Science.gov (United States)

    Jamal, Farrukh; Haque, Quazi S; Singh, Sangram

    2016-01-01

    Diverse group of agro-chemicals are indiscriminately sprayed by the farmers for pest control to enhance crop yield. About 25 million agricultural workers in the developing world suffer from at least one episode of poisoning each year, mainly by anticholinesterase- like organophosphates (OPs). The present study was aimed to establish the OP toxicity in 187 occupationally exposed pesticide sprayers of mango plantation in rural Malihabad, Lucknow, in terms of neuro-cognitive impairment, mental health status, clinical symptoms, diabetes, and hematological factors. The exposed group was compared to 187 pesticides-unexposed normal healthy persons engaged in normal usual agricultural work (age, sex and education corresponding to age group of selected subject group) from Rural Malihabad, Lucknow (India). Neuro-cognitive impairment was measured using the Subjective Neurocognition Inventory and mental health status using the General Health questionnaire-28. The subjects were also tested for biochemical and enzymatic parameters. The exposed farmers showed alterations in enzymatic and clinical parameters. While the rates of anxiety / insomnia and severe depression were also significantly higher in the pesticide sprayers, disorders affecting psychomotor speed, selective attention, divided attention, verbal memory, nonverbal memory, prospective memory, spatial functioning, and initiative/energy were all lower in the sprayers. Pesticide sprayers showed a number of clinical symptoms like eczema, saliva secretion, fatigue, headache, sweating, abdominal pain, nausea, superior distal muscle weakness, inferior distal muscle weakness, hand tingling and etc. which all significantly correlated with the number of working years. These findings suggested that farmers who work with OPs are prone to neuro-psychological disorders and diabetes.

  3. Organophosphorus pesticide and ester analysis by using comprehensive two-dimensional gas chromatography with flame photometric detection

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiangping; Li, Dengkun; Li, Jiequan [Nanjing Centre for Disease Control and Prevention, Zizhulin Street, Gulou 210003, Nanjing (China); Rose, Gavin [Department of Environment and Primary Industries, Macleod Centre, Ernest Jones Drive, Macleod, Vic 3085 (Australia); Marriott, Philip J., E-mail: philip.marriott@monash.edu [Australian Centre for Research on Separation Science, School of Chemistry, Monash University, Wellington Road, Clayton 3800 (Australia)

    2013-12-15

    Highlights: • GC × GC-FPD(P-mode) was applied to detection of 37 phosphorus (P)-containing compounds. • The method improves resolution of P-compounds that coelute in the first dimension. • P-compounds are analyzed with excellent sensitivity supported by cryogenic modulation. • The FPD(P-mode) selectivity allows analysis in high hydrocarbon (H/C) matrix. • Soil samples and spiked chemical weapon compounds in H/C matrix are readily screened. -- Abstract: Thirty-seven phosphorus (P)-containing compounds comprising organophosphorus pesticides and organophosphate esters were analyzed by using comprehensive two-dimensional gas chromatography with flame photometric detection in P mode (GC × GC-FPD(P)), with a non-polar/moderately polar column set. A suitable modulation temperature and period was chosen based on experimental observation. A number of co-eluting peak pairs on the {sup 1}D column were well separated in 2D space. Excellent FPD(P) detection selectivity, responding to compounds containing the P atom, produces clear 2D GC × GC plots with little interference from complex hydrocarbon matrices. Limits of detection (LOD) were within the range of 0.0021–0.048 μmol L{sup −1}, and linear calibration correlation coefficients (R{sup 2}) for all 37 P-compounds were at least 0.998. The P-compounds were spiked in 2% diesel and good reproducibility for their response areas and retention times was obtained. Spiked recoveries were 88%–157% for 5 μg L{sup −1} and 80%–138% for 10 μg L{sup −1} spiked levels. Both {sup 1}t{sub R} and {sup 2}t{sub R} shifts were noted when the content of diesel was in excess of 5% in the matrix. Soil samples were analyzed by using the developed method; some P-compounds were positively detected. In general, this study shows that GC × GC-FPD(P) is an accurate, sensitive and simple method for P-compound analysis in complicated environmental samples.

  4. A set of triple-resonance nuclear magnetic resonance experiments for structural characterization of organophosphorus compounds in mixture samples

    Energy Technology Data Exchange (ETDEWEB)

    Koskela, Harri, E-mail: Harri.T.Koskela@helsinki.fi [VERIFIN, University of Helsinki, P.O. Box 55, FIN-00014 Helsinki (Finland)

    2012-11-02

    Highlights: Black-Right-Pointing-Pointer New {sup 1}H, {sup 13}C, {sup 31}P triple-resonance NMR pulse experiments. Black-Right-Pointing-Pointer Analysis of organophosphorus (OP) compounds in complex matrix. Black-Right-Pointing-Pointer Selective extraction of {sup 1}H, {sup 31}P, and {sup 13}C chemical shifts and connectivities. Black-Right-Pointing-Pointer More precise NMR identification of OP nerve agents and their degradation products. - Abstract: The {sup 1}H, {sup 13}C correlation NMR spectroscopy utilizes J{sub CH} couplings in molecules, and provides important structural information from small organic molecules in the form of carbon chemical shifts and carbon-proton connectivities. The full potential of the {sup 1}H, {sup 13}C correlation NMR spectroscopy has not been realized in the Chemical Weapons Convention (CWC) related verification analyses due to the sample matrix, which usually contains a high amount of non-related compounds obscuring the correlations of the relevant compounds. Here, the results of the application of {sup 1}H, {sup 13}C, {sup 31}P triple-resonance NMR spectroscopy in characterization of OP compounds related to the CWC are presented. With a set of two-dimensional triple-resonance experiments the J{sub HP}, J{sub CH} and J{sub PC} couplings are utilized to map the connectivities of the atoms in OP compounds and to extract the carbon chemical shift information. With the use of the proposed pulse sequences the correlations from the OP compounds can be recorded without significant artifacts from the non-OP compound impurities in the sample. Further selectivity of the observed correlations is achieved with the application of phosphorus band-selective pulse in the pulse sequences to assist the analysis of multiple OP compounds in mixture samples. The use of the triple-resonance experiments in the analysis of a complex sample is shown with a test mixture containing typical scheduled OP compounds, including the characteristic degradation

  5. Reactivation of organophosphate-inhibited human, Cynomolgus monkey, swine and guinea pig acetylcholinesterase by MMB-4: A modified kinetic approach

    International Nuclear Information System (INIS)

    Worek, Franz; Wille, Timo; Aurbek, Nadine; Eyer, Peter; Thiermann, Horst

    2010-01-01

    Treatment of poisoning by highly toxic organophosphorus compounds (OP, nerve agents) is a continuous challenge. Standard treatment with atropine and a clinically used oxime, obidoxime or pralidoxime is inadequate against various nerve agents. For ethical reasons testing of oxime efficacy has to be performed in animals. Now, it was tempting to investigate the reactivation kinetics of MMB-4, a candidate oxime to replace pralidoxime, with nerve agent-inhibited acetylcholinesterase (AChE) from human and animal origin in order to provide a kinetic basis for the proper assessment of in vivo data. By applying a modified kinetic approach, allowing the use of necessary high MMB-4 concentrations, it was possible to determine the reactivation constants with sarin-, cyclosarin-, VX-, VR- and tabun-inhibited AChE. MMB-4 exhibited a high reactivity and low affinity towards OP-inhibited AChE, except of tabun-inhibited enzyme where MMB-4 had an extremely low reactivity. Species differences between human and animal AChE were low (Cynomolgus) to moderate (swine, guinea pig). Due to the high reactivity of MMB-4 a rapid reactivation of inhibited AChE can be anticipated at adequate oxime concentrations which are substantially higher compared to HI-6. Additional studies are necessary to determine the in vivo toxicity, tolerability and pharmacokinetics of MMB-4 in humans in order to enable a proper assessment of the value of this oxime as an antidote against nerve agent poisoning.

  6. Reactivation of organophosphate-inhibited human, Cynomolgus monkey, swine and guinea pig acetylcholinesterase by MMB-4: a modified kinetic approach.

    Science.gov (United States)

    Worek, Franz; Wille, Timo; Aurbek, Nadine; Eyer, Peter; Thiermann, Horst

    2010-12-15

    Treatment of poisoning by highly toxic organophosphorus compounds (OP, nerve agents) is a continuous challenge. Standard treatment with atropine and a clinically used oxime, obidoxime or pralidoxime is inadequate against various nerve agents. For ethical reasons testing of oxime efficacy has to be performed in animals. Now, it was tempting to investigate the reactivation kinetics of MMB-4, a candidate oxime to replace pralidoxime, with nerve agent-inhibited acetylcholinesterase (AChE) from human and animal origin in order to provide a kinetic basis for the proper assessment of in vivo data. By applying a modified kinetic approach, allowing the use of necessary high MMB-4 concentrations, it was possible to determine the reactivation constants with sarin-, cyclosarin-, VX-, VR- and tabun-inhibited AChE. MMB-4 exhibited a high reactivity and low affinity towards OP-inhibited AChE, except of tabun-inhibited enzyme where MMB-4 had an extremely low reactivity. Species differences between human and animal AChE were low (Cynomolgus) to moderate (swine, guinea pig). Due to the high reactivity of MMB-4 a rapid reactivation of inhibited AChE can be anticipated at adequate oxime concentrations which are substantially higher compared to HI-6. Additional studies are necessary to determine the in vivo toxicity, tolerability and pharmacokinetics of MMB-4 in humans in order to enable a proper assessment of the value of this oxime as an antidote against nerve agent poisoning. Copyright © 2010 Elsevier Inc. All rights reserved.

  7. Occurrence and distribution of organophosphorus flame retardants and plasticizers in anthropogenically affected groundwater.

    Science.gov (United States)

    Regnery, J; Püttmann, W; Merz, C; Berthold, G

    2011-02-01

    Occurrence and distribution of chlorinated and non-chlorinated organophosphates in 72 groundwater samples from Germany under different recharge/infiltration conditions were investigated. Tris(2-chloro-1-methylethyl) phosphate (TCPP) and tris(2-chloroethyl) phosphate (TCEP) were the most frequently detected organophosphates in groundwater samples. Highest individual organophosphate concentrations (>0.1 µg L(-1)) were determined in groundwater polluted by infiltrating leachate and groundwater recharged via riverbank filtration of organophosphate-loaded recipients. In samples from springs and deep groundwater monitoring wells that are not affected by surface waters, organophosphate concentrations were mostly below the limit of detection. The occurrence (3-9 ng L(-1)) of TCPP and TCEP in samples from aquifers with groundwater ages between 20 and 45 years indicates the persistence of both compounds within the aquifer. At urban sites organophosphate-loaded precipitation, surface runoff, and leakage of wastewater influenced groundwater quality. For rural sites, where groundwater recharge is only influenced by precipitation, organophosphates were very rarely detectable in groundwater.

  8. Neurocognitive, mental health, and glucose disorders in farmers exposed to organophosphorus pesticides.

    Science.gov (United States)

    Malekirad, Ali Akbar; Faghih, Mahya; Mirabdollahi, Mansuoreh; Kiani, Mahdi; Fathi, Arezoo; Abdollahi, Mohammad

    2013-01-01

    About 25 million agricultural workers in the developing world suffer from at least one episode of poisoning each year, mainly by anticholinesterase-like organophosphates (OPs). The objective of this cross-sectional study was to establish the OP toxicity in 187 occupationally exposed farmers in terms of neurocognitive impairment, mental health status, clinical symptoms, diabetes, and haematological factors. The exposed group was compared to 187 healthy age-, sex-, and education-matching controls. Neurocognitive impairment was measured using the Subjective Neurocognition Inventory (SNI) and mental health status using the General Health Questionnaire-28 (GHQ-28). The subjects were also tested for fasting blood glucose (FBG), blood urea nitrogen (BUN), cholesterol (CL), triglycerides (TG), creatinine, oral glucose tolerance test (GTT), high-density lipoprotein (HDL), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP). The exposed farmers showed higher FBG (peczema, saliva secretion, fatigue, headache, sweating, abdominal pain, nausea, superior distal muscle weakness, inferior distal muscle weakness, inferior proximal muscle weakness, breath muscle weakness, hand tingling, foot tingling, epiphoria, polyuria, miosis, dyspnoea, bradycardia, and rhinorrhoea, which all significantly correlated with the number of working years. These findings indicate that farmers who work with OPs are prone to neuropsychological disorders and diabetes.

  9. Simultaneous determination of organophosphorus pesticides and phthalates in baby food samples by ultrasound-vortex-assisted liquid-liquid microextraction and GC-IT/MS.

    Science.gov (United States)

    Notardonato, Ivan; Salimei, Elisabetta; Russo, Mario Vincenzo; Avino, Pasquale

    2018-05-01

    Baby foods are either a soft, liquid paste or an easily chewed food since babies lack developed muscles and teeth to chew effectively. Babies typically move to consuming baby food once nursing or formula is not sufficient for the child's appetite. Some commercial baby foods have been criticized for their contents. This article focuses on the simultaneous determination of organophosphorus pesticides and phthalates by means of a method based on ultrasound-vortex-assisted liquid-liquid microextraction coupled with gas chromatography-ion trap mass spectrometry (GC-IT/MS). The protocol developed allowed the determination of six phthalates [dimethyl phthalate, diethyl phthalate, dibutyl phthalate, isobutyl cyclohexyl phthalate, benzyl butyl phthalate, bis(2-ethylhexyl) phthalate] and 19 organophosphorus pesticides. Freeze-dried product samples (0.1-0.2 g) were dissolved in 10 mL of warm distilled water along with 5 μL of an internal standard (anthracene at 10 mg mL -1 in acetone): the choice of extraction solvent was studied, with the most suitable being n-heptane, which is used for phthalate determination in similar matrices. The solution, held for 5 min in a vortex mixer and for 6 min in a 100-W ultrasonic bath to favor solvent dispersion and consequently analyte extraction, was centrifuged at 4000 rpm for 30 min. Then 1 μL was injected into the GC-IT/MS system (SE-54 capillary column; length 30 m, inner diameter 250 μm, film thickness 0.25 μm). All analytical parameters investigated are discussed in depth. The method was applied to real commercial freeze-dried samples: significant contaminant concentrations were not found. Graphical abstract Simultaneous and sensitive determination of organophosphorus pesticides and phthalates in baby foods by the ultrasound-vortex-assisted liquid-liquid microextraction ֪gas chromatography-ion trap mass spectrometry procedure. 1 methacrifos, 2 pirofos, 3 phorate, 4 seraphos, 5 diazinon, 6 etrimphos, 7 dichlofenthion, 8

  10. Avoidance behaviour response and esterase inhibition in the earthworm, Lumbricus terrestris, after exposure to chlorpyrifos.

    Science.gov (United States)

    Martínez Morcillo, S; Yela, J L; Capowiez, Y; Mazzia, C; Rault, M; Sanchez-Hernandez, Juan C

    2013-05-01

    The avoidance response of earthworms to polluted soils has been standardised using a simple and low-cost test, which facilitates soil toxicity screening. In this study, the avoidance response of Lumbricus terrestris was quantified in chlorpyrifos-spiked soils, depending on the pesticide concentration and exposure duration. The inhibition of acetylcholinesterase (AChE) and carboxylesterase (CbE) activities was also determined as indirect measures of pesticide bioavailability. The effects of different chlorpyrifos concentrations were examined in a standardised test (two-chamber system) with 0.6, 3 and 15 mg/kg chlorpyrifos. A modification of the test involved a pre-exposure step (24, 48 or 72 h) in soils spiked with 15 mg/kg. In both protocols, earthworms were unable to avoid the contaminated soils. However, the esterase activities showed that all earthworms were exposed to chlorpyrifos. Acetylcholinesterase activity did not change in earthworms in the standardised behavioural test (0.58 ± 0.20 U/mg protein, mean ± SD; n = 72), whereas the CbE activity was significantly inhibited (62-87 % inhibition) in earthworms exposed to 3 and 15 mg/kg. In the modified test, earthworms had greatly inhibited AChE activity (0.088 ± 0.034 U/mg protein, n = 72), which was supported by reactivation of the inhibited enzyme activity in the presence of pralidoxime (2-PAM). Similarly, the CbE activity was significantly inhibited in earthworms with all treatments. This study suggests that the avoidance behaviour test for organophosphorus-contaminated soils could be supported by specific biomarkers to facilitate a better understanding of pesticide exposure and toxicity during this test.

  11. High-performance liquid chromatography using reversed-phase stationary phases dynamically modified with organophosphorus compound for the separation and determination of lanthanoid elements

    International Nuclear Information System (INIS)

    Tsuyoshi, Akira; Akiba, Kenichi

    2000-01-01

    An acidic organophosphorus compound, 2-ethylhexylphosphonic acid mono-2-ethlhexyl ester (EHPA), has been applied to reversed-phase high-performance liquid chromatography (RP-HPLC). The reversed-phase stationary phase was dynamically modified with EHPA by flowing the mobile phase of an acetone-water mixture containing the extracting regent. The retention of lanthanoid elements was widely varied by changing the conditions of the mobile phase, i.e., the pH, the EHPA concentration and the acetone content. The selectivity of EHPA is well reflected to the chromatographic systems, and a precise separation of lanthanoid elements was achieved with sufficient resolution. The determination of Sm was examined in the presence of a large amount of Nd. A linear calibration graph was obtained for Sm at the level of 10 -7 mol dm -3 , in the presence of 1x10 -4 mol dm -3 of Nd. (author)

  12. The Effectiveness of Reward and Punishment Contingencies on Response Inhibition

    Science.gov (United States)

    Costantini, Arthur F.; Hoving, Kenneth L.

    1973-01-01

    The relative effectiveness of reward and punishment on the development of response inhibition was evaluated developmentally with kindergarteners and second graders. Removal of positive reinforcers was apparently more effective than reward in producing inhibiting at both age levels. Transfer of inhibition training was also evaluated. (DP)

  13. INHIBITION IN SPEAKING PERFORMANCE

    OpenAIRE

    Humaera, Isna

    2015-01-01

    The most common problem encountered by the learner in the languageacquisition process is learner inhibition. Inhibition refers to a temperamentaltendency to display wariness, fearfulness, or restrain in response tounfamiliar people, objects, and situations. There are some factors that causeinhibition, such as lack of motivation, shyness, self-confidence, self-esteem,and language ego. There are also levels of inhibition, it refers to kinds ofinhibition and caused of inhibition itself. Teacher ...

  14. Inhibition of plasma butyrylcholinesterase activity in the lizard Gallotia galloti palmae by pesticides: a field study

    International Nuclear Information System (INIS)

    Sanchez-Hernandez, Juan C.; Carbonell, R.; Henriquez Perez, A.; Montealegre, M.; Gomez, L.

    2004-01-01

    A field study was performed to evaluate the effect of exposure to organophosphorus (OP) and carbamate (CB) pesticides on the lizard Gallotia galloti palmae. Butyrylcholinesterase (BChE) activity was measured in the plasma of 420 lizards collected from agricultural and reference areas on the Island of La Palma (Canary Islands, Spain) in two sampling periods. Exposure to cholinesterase-inhibiting pesticides was evaluated by a statistical criterion based on a threshold value (two standard deviations below the mean enzyme activity) calculated for the reference group, and a chemical criterion based on the in vitro reactivation of BChE activity using pyridine-2-aldoxime methochloride (2-PAM) or after water dilution of the sample. Mean (±SD) BChE activity for lizards from agricultural areas was significantly lower (Fuencaliente site = 2.00 ± 0.98 μmol min -1 ml -1 , Tazacorte site = 2.88 ± 1.08) than that for lizards from the reference areas (Los Llanos site = 3.06 ± 1.17 μmol min -1 ml -1 , Tigalate site = 3.96 ± 1.62). According to the statistical criterion, the number of lizards with BChE depressed was higher at Fuencaliente (22% of males and 25.4% of females) than that sampled at Tazacorte (7.8% of males and 6.2% of females). According to the chemical criterion, Fuencaliente also yielded a higher number of individuals (112 males and 47 females) with BChE activity inhibited by both OP and CB pesticides. CBs appeared to be the pesticides most responsible for BChE inhibition because most of the samples showed reactivation of BChE activity after water treatment (63.3% from Fuencaliente and 29% from Tazacorte). We concluded that the use of reactivation techniques on plasma BChE activity is a better and more accurate method for assessing field exposure to OP/CB pesticides in this lizard species than making direct comparisons of enzyme activity levels between sampling areas. - Capsule: Chemical reactivation of lizard BChE activity is a suitable diagnostic method for

  15. 热应激复合敌敌畏中毒对小鼠全血乙酰胆碱脂酶和组织抗氧化能力的影响%Effects of heat stress with organophosphorus pesticide intoxication on blood AChE activity and tissue anti-oxidation ability in mice

    Institute of Scientific and Technical Information of China (English)

    蔡颖; 谢首佳; 赵远鹏; 董兆君; 邹仲敏

    2012-01-01

    Objective To explore the combined effect of heat stress with organophosphorus O , O-dimethyl-O-2, 2-di-chlorovinylphosphate (DDVP) intoxication on blood acetyl choli nest erase (AChE) activity and tissue lipid peroxidation. Methods Fifty-four mice were randomly divided into control group , heat stress group and heat stress combined with DDVP poisoning group (the combined group). Mice were put into experiment chamber with (60 ±5)% relative humidity. The chamber temperature was 24℃ for control group , and 38 or 40℃; for heat stress group. One hour later, mice in combined group were intraperitoneally given 9 or 15 mg/kg DDVP. Saline of an equal volume was applied to control and heat stress groups. After 30 minutes, the mice were sacrificed and samples of the blood , heart, brain, and liver were collected. Blood AChE activity, tissue SOD activity, MDA content and · OH inhibiting ability in tissue homogenates of the brain , heart and liver were determined respectively. Results Mice became agitated and restless with increased activity when exposed to 38 or 40℃ ambient temperature. Water intake and body mass were decreased . Compared with temperature-matched controls, the heat exposure combined with DDVP poisoning at 38 or 40℃ caused significant decline of blood AChE activity , tissue SOD activity and · OH inhibiting ability, and increase of tissue MDA content in the brain , heart and liver ( P < 0. 05 ). Heat stress and organophosphorus pesticide intoxication showed synergistic interaction between the above parameters . Conclusion Under present experimental conditions , both ambient temperature and organophosphorus poisoning can significant -ly suppress the blood AChE activity while causing enhanced tissue lipid peroxidation . These data suggest that oxidative stress plays a role in the aggregative effect of organophosphorus intoxication under high ambient temperature .%目的 研究热应激复合有机磷敌敌畏(O,O-dimethyl-O-2,2-dichlorovinylphosphate

  16. The development of children's inhibition: Does parenting matter?

    OpenAIRE

    Roskam, I.; Stievenart, Marie; Meunier, J.-C.; Noël, M.-P.

    2014-01-01

    Whereas a large body of research has investigated the maturation of inhibition in relation to the prefrontal cortex, far less research has been devoted to environmental factors that could contribute to inhibition improvement. The aim of the current study was to test whether and to what extent parenting matters for inhibition development from 2 to 8. years of age. Data were collected from 421 families, with 348 mother-child dyads and 342 father-child dyads participating. Children's inhibition ...

  17. Synergistic solvent extraction investigation of Am (III), Eu (III), Zn(II), and Cs(I), using 2-heptyl-2-methyl-nonanoic acid mixed with different organophosphorus compounds from nitrate media. Vol. 3

    International Nuclear Information System (INIS)

    El-Naggar, H.A.; Ramadan, A.; Abdel-Fattah, A.

    1996-01-01

    Extraction studies for investigating the effect of mixing 2-heptyl-2-methyl nonanoic acid (HA) with a number of organophosphorus compounds; namely tributyl phosphate (TBP), terphenyl phosphate oxide (TPPO); tri octyl phosphine oxide (TOPO) or bis-2-(ethyl hexyl) phosphoric acid (HDEHP) in benzene on the extraction of trace elements Am(III), Eu(III), Zn(II), and Cs(I) from nitrate media of ionic strength, I=0.1 M were carried out. The effect of adding different organophosphorus compounds to HA was tested to account for the presence or absence of the phenomenon of synergism. It was found that TBP, TPPO, and TOPO causing some antagonistic effects for the elements studied. Extraction enhancement was only observed with bis- (2-ethyl-hexyl) -phosphoric acid (HDEHP) for all the elements investigated. The extraction mechanisms as well as the thermodynamic parameters for the mixed extracted species are discussed. 19 figs

  18. Synergistic solvent extraction investigation of Am (III), Eu (III), Zn(II), and Cs(I), using 2-heptyl-2-methyl-nonanoic acid mixed with different organophosphorus compounds from nitrate media. Vol. 3

    Energy Technology Data Exchange (ETDEWEB)

    El-Naggar, H A; Ramadan, A; Abdel-Fattah, A [Nuclear Chemistry Department, Hot Laboratories Center, Atomic Energy Authority, Cairo (Egypt)

    1996-03-01

    Extraction studies for investigating the effect of mixing 2-heptyl-2-methyl nonanoic acid (HA) with a number of organophosphorus compounds; namely tributyl phosphate (TBP), terphenyl phosphate oxide (TPPO); tri octyl phosphine oxide (TOPO) or bis-2-(ethyl hexyl) phosphoric acid (HDEHP) in benzene on the extraction of trace elements Am(III), Eu(III), Zn(II), and Cs(I) from nitrate media of ionic strength, I=0.1 M were carried out. The effect of adding different organophosphorus compounds to HA was tested to account for the presence or absence of the phenomenon of synergism. It was found that TBP, TPPO, and TOPO causing some antagonistic effects for the elements studied. Extraction enhancement was only observed with bis- (2-ethyl-hexyl) -phosphoric acid (HDEHP) for all the elements investigated. The extraction mechanisms as well as the thermodynamic parameters for the mixed extracted species are discussed. 19 figs.

  19. Zero valent Fe-reduced graphene oxide quantum dots as a novel magnetic dispersive solid phase microextraction sorbent for extraction of organophosphorus pesticides in real water and fruit juice samples prior to analysis by gas chromatography-mass spectrometry.

    Science.gov (United States)

    Akbarzade, Samaneh; Chamsaz, Mahmoud; Rounaghi, Gholam Hossein; Ghorbani, Mahdi

    2018-01-01

    A selective and sensitive magnetic dispersive solid-phase microextraction (MDSPME) coupled with gas chromatography-mass spectrometry was developed for extraction and determination of organophosphorus pesticides (Sevin, Fenitrothion, Malathion, Parathion, and Diazinon) in fruit juice and real water samples. Zero valent Fe-reduced graphene oxide quantum dots (rGOQDs@ Fe) as a new and effective sorbent were prepared and applied for extraction of organophosphorus pesticides using MDSPME method. In order to study the performance of this new sorbent, the ability of rGOQDs@ Fe was compared with graphene oxide and magnetic graphene oxide nanocomposite by recovery experiments of the organophosphorus pesticides. Several affecting parameters in the microextraction procedure, including pH of donor phase, donor phase volume, stirring rate, extraction time, and desorption conditions such as the type and volume of solvents and desorption time were thoroughly investigated and optimized. Under the optimal conditions, the method showed a wide linear dynamic range with R-square between 0.9959 and 0.9991. The limit of detections, the intraday and interday relative standard deviations (n = 5) were less than 0.07 ngmL -1 , 4.7, and 8.6%, respectively. The method was successfully applied for extraction and determination of organophosphorus pesticides in real water samples (well, river and tap water) and fruit juice samples (apple and grape juice). The obtained relative recoveries were in the range of 82.9%-113.2% with RSD percentages of less than 5.8% for all the real samples.

  20. 31P-edited diffusion-ordered 1H NMR spectroscopy for the spectral isolation and identification of organophosphorus compounds related to chemical weapons agents and their degradation products.

    Science.gov (United States)

    Mayer, Brian P; Valdez, Carlos A; Hok, Saphon; Chinn, Sarah C; Hart, Bradley R

    2012-12-04

    Organophosphorus compounds represent a large class of molecules that include pesticides, flame-retardants, biologically relevant molecules, and chemical weapons agents (CWAs). The detection and identification of organophosphorus molecules, particularly in the cases of pesticides and CWAs, are paramount to the verification of international treaties by various organizations. To that end, novel analytical methodologies that can provide additional support to traditional analyses are important for unambiguous identification of these compounds. We have developed an NMR method that selectively edits for organophosphorus compounds via (31)P-(1)H heteronuclear single quantum correlation (HSQC) and provides an additional chromatographic-like separation based on self-diffusivities of the individual species via (1)H diffusion-ordered spectroscopy (DOSY): (1)H-(31)P HSQC-DOSY. The technique is first validated using the CWA VX (O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate) by traditional two-dimensional DOSY spectra. We then extend this technique to a complex mixture of VX degradation products and identify all the main phosphorus-containing byproducts generated after exposure to a zinc-cyclen organometallic homogeneous catalyst.

  1. Reactivation of organophosphate-inhibited human acetylcholinesterase by isonitrosoacetone (MINA): a kinetic analysis.

    Science.gov (United States)

    Worek, Franz; Thiermann, Horst

    2011-11-15

    Treatment of poisoning by highly toxic organophosphorus compounds (OP) with atropine and an acetylcholinesterase (AChE) reactivator (oxime) is of limited effectiveness in case of different nerve agents and pesticides. One challenge is the reactivation of OP-inhibited brain AChE which shows inadequate success with charged pyridinium oximes. Recent studies with high doses of the tertiary oxime isonitrosoacetone (MINA) indicated a beneficial effect on central and peripheral AChE and on survival in nerve agent poisoned guinea pigs. Now, an in vitro study was performed to determine the reactivation kinetics of MINA with tabun-, sarin-, cyclosarin-, VX- and paraoxon-inhibited human AChE. MINA showed an exceptionally low affinity to inhibited AChE but, with the exception of tabun-inhibited AChE, a moderate to high reactivity. In comparison to the pyridinium oximes obidoxime, 2-PAM and HI-6 the affinity and reactivity of MINA was in most cases lower and in relation to the most effective reactivators, the second order reactivation constant of MINA was 500 to 3400-fold lower. Hence, high in vivo MINA concentrations would be necessary to achieve at least partial reactivation. This assumption corresponds to in vivo data showing a dose-dependent effect on reactivation and survival in animals. In view, of the toxic potential of MINA in animals human studies would be necessary to determine the tolerability and pharmacokinetics of MINA in order to enable a proper assessment of the value of this oxime as an antidote in OP poisoning. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  2. Pilot-scale incineration of wastes with high content of chlorinated and non-halogenated organophosphorus flame retardants used as alternatives for PBDEs

    International Nuclear Information System (INIS)

    Matsukami, Hidenori; Kose, Tomohiro; Watanabe, Mafumi; Takigami, Hidetaka

    2014-01-01

    Chlorinated and non-halogenated organophosphorus flame retardants (OPFRs) including tris(2-chloroisopropyl) phosphate (TCIPP), diethylene glycol bis(di(2-chloroisopropyl) phosphate) (DEG-BDCIPP), triphenyl phosphate (TPHP), and bisphenol A bis(diphenyl phosphate) (BPA-BDPP) have been used increasingly as alternatives to polybrominated diphenyl ethers and other brominated flame retardants. For this study, five batches of incineration experiments of wastes containing approximately 1% of TCIPP, DEG-BDCIPP, TPHP, and BPA-BDPP were conducted using a pilot-scale incinerator. Destruction and emission behaviors of OPFRs were investigated along with the effects on behaviors of unintentional persistent organic pollutants (POPs) such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (dl-PCBs), hexachlorobenzene (HCB), pentachlorobenzene (PeCB), and pentachlorophenol (PCP). Incineration conditions were chosen according to current regulations for waste incinerators in Japan and UNEP. The OPFRs in the input materials were mainly destroyed in the primary combustion with destruction efficiencies greater than 99.999%. Concentrations of the OPFRs in the exhaust gases and ash were, respectively, < 0.01–0.048 μg m −3 and < 0.5–68 μg kg −1 . Almost all of the total phosphorus in the input materials was partitioned into the ash, but less into final exit gases, indicating negligible emissions of volatile phosphorus compounds during incineration. Inputs of chlorinated OPFRs did not affect the formation markedly. Destruction and emission behaviors of unintentional POPs were investigated. Emissions of such POPs in exhaust gases and the ash were lower than the Japanese and international standards. Results show that even in wastes with high contents of chlorinated and non-halogenated OPFRs, waste incineration by the current regulations for the waste incinerators can control environmental emissions of OPFRs and

  3. Pilot-scale incineration of wastes with high content of chlorinated and non-halogenated organophosphorus flame retardants used as alternatives for PBDEs

    Energy Technology Data Exchange (ETDEWEB)

    Matsukami, Hidenori, E-mail: matsukami.hidenori@nies.go.jp [Center for Material Cycles and Waste Management Research, National Institute for Environmental Studies (NIES), 16-2 Onogawa, Tsukuba 305-8506 (Japan); Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa 277-8563 (Japan); Kose, Tomohiro [Faculty of Applied Life Sciences, Niigata University of Pharmacy and Applied Life Sciences, 265-1, Higashijima, Akiha-ku, Niigata 956-8603 (Japan); Watanabe, Mafumi [Center for Material Cycles and Waste Management Research, National Institute for Environmental Studies (NIES), 16-2 Onogawa, Tsukuba 305-8506 (Japan); Takigami, Hidetaka [Center for Material Cycles and Waste Management Research, National Institute for Environmental Studies (NIES), 16-2 Onogawa, Tsukuba 305-8506 (Japan); Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa 277-8563 (Japan)

    2014-09-15

    Chlorinated and non-halogenated organophosphorus flame retardants (OPFRs) including tris(2-chloroisopropyl) phosphate (TCIPP), diethylene glycol bis(di(2-chloroisopropyl) phosphate) (DEG-BDCIPP), triphenyl phosphate (TPHP), and bisphenol A bis(diphenyl phosphate) (BPA-BDPP) have been used increasingly as alternatives to polybrominated diphenyl ethers and other brominated flame retardants. For this study, five batches of incineration experiments of wastes containing approximately 1% of TCIPP, DEG-BDCIPP, TPHP, and BPA-BDPP were conducted using a pilot-scale incinerator. Destruction and emission behaviors of OPFRs were investigated along with the effects on behaviors of unintentional persistent organic pollutants (POPs) such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (dl-PCBs), hexachlorobenzene (HCB), pentachlorobenzene (PeCB), and pentachlorophenol (PCP). Incineration conditions were chosen according to current regulations for waste incinerators in Japan and UNEP. The OPFRs in the input materials were mainly destroyed in the primary combustion with destruction efficiencies greater than 99.999%. Concentrations of the OPFRs in the exhaust gases and ash were, respectively, < 0.01–0.048 μg m{sup −3} and < 0.5–68 μg kg{sup −1}. Almost all of the total phosphorus in the input materials was partitioned into the ash, but less into final exit gases, indicating negligible emissions of volatile phosphorus compounds during incineration. Inputs of chlorinated OPFRs did not affect the formation markedly. Destruction and emission behaviors of unintentional POPs were investigated. Emissions of such POPs in exhaust gases and the ash were lower than the Japanese and international standards. Results show that even in wastes with high contents of chlorinated and non-halogenated OPFRs, waste incineration by the current regulations for the waste incinerators can control environmental emissions of

  4. Metal Ion-Catalyzed Alcoholysis as a Strategy for the High Loading Destruction of Chemical Warfare Organophosphorus Agents

    Science.gov (United States)

    2013-11-01

    agents (CWAs). Whether these inhibitors are used as pesticides or CWAs, all act in the same way by inhibiting an enzyme (a cholinesterase ), thereby...phosphinate, and phosphonate esters are potent acetylcholinesterase inhibitors that are used as animal and crop protectants and chemical warfare...for these inhibitors are used annually, accounting for 70% of all insecticides used for agriculture, in homes and gardens, and for government

  5. Exogenously triggered response inhibition in developmental stuttering.

    Science.gov (United States)

    Eggers, Kurt; De Nil, Luc F; Van den Bergh, Bea R H

    2018-06-01

    The purpose of the present study was to examine relations between children's exogenously triggered response inhibition and stuttering. Participants were 18 children who stutter (CWS; mean age = 9;01 years) and 18 children who not stutter (CWNS; mean age = 9;01 years). Participants were matched on age (±3 months) and gender. Response inhibition was assessed by a stop signal task (Verbruggen, Logan, & Stevens, 2008). Results suggest that CWS, compared to CWNS, perform comparable to CWNS in a task where response control is externally triggered. Our findings seem to indicate that previous questionnaire-based findings (Eggers, De Nil, & Van den Bergh, 2010) of a decreased efficiency of response inhibition cannot be generalized to all types of response inhibition. Copyright © 2018 Elsevier Inc. All rights reserved.

  6. Training and Transfer Effects of Response Inhibition Training in Children and Adults

    Science.gov (United States)

    Zhao, Xin; Chen, Ling; Maes, Joseph H. R.

    2018-01-01

    Response inhibition is crucial for mental and physical health but studies assessing the trainability of this type of inhibition are rare. Thirty-nine children aged 10-12 years and 46 adults aged 18-24 years were assigned to an adaptive go/no-go inhibition training condition or an active control condition. Transfer of training effects to…

  7. Kinetic Spectrophotometric Method for the 1,4-Diionic Organophosphorus Formation in the Presence of Meldrum′s Acid: Stopped-Flow Approach

    Directory of Open Access Journals (Sweden)

    Fatemeh Ghodsi

    2016-11-01

    Full Text Available The kinetics of the reaction between triphenylphosphine (TPP and dimethyl acetylenedicarboxylate (DMAD in the presence of Meldrum’s acid (MA for the generation of the 1,4-diionic organophosphorus compound has been investigated using the stopped-flow and UV-VIS spectrophotometry techniques. The first step of the reaction between TPP and DMAD for the generation of (I1 in ethanol was followed by the stopped-flow apparatus. This step was recognized as a fast step. The reaction between the intermediate (I1 and MA showed first-order kinetics, and it was followed by the UV-VIS spectrophotometry technique. The activation parameters for the slow step of the proposed mechanism were determined using two linearized forms of the Eyring equation. From the temperature, concentration and solvent studies, the activation energy (Ea = 20.16 kJ·mol−1 and the related activation parameters (ΔG‡ = 71.17 ± 0.015 kJ·mol−1, ΔS‡ = −185.49 ± 0.026 J·mol−1 and ΔH‡ =17.72 ± 0.007 kJ·mol−1 were calculated. The experimental data indicated that the reaction was zero-order in MA and second-order overall. The proposed mechanism was confirmed with the observed kinetic data obtained from the UV-VIS and stopped-flow techniques.

  8. A novel amperometric biosensor based on covalently attached multilayer assemblies of gold nanoparticles, diazo-resins and acetylcholinesterase for the detection of organophosphorus pesticides.

    Science.gov (United States)

    Jiang, Bin; Dong, Pei; Zheng, Jianbin

    2018-06-01

    Using an ionic layer-by-layer self-assembly technique, colloidal gold nanoparticles (AuNPs) and diazo-resins (DAR) were immobilised on the surface of a p-aminobenzenesulfonic acid-modified glassy carbon electrode to form a matrix composite membrane for acetylcholinesterase (AChE) immobilisation. Photo-sensitive DAR was used as the assembly interlayer to convert the ionic bond into a covalent bond to improve the biosensor stability. These fabrication processes were followed by electrochemical impedance spectroscopy and cyclic voltammetry to verify the membrane formation. Because of the introduction of AuNPs/DAR/AChE biofilms, the modified electrode exhibited excellent electron transfer mediation and electrical conductivity. In addition, it exhibited high sensitivity in the range of linear concentration from 1.0 × 10 -8 to 1.0 × 10 -12 g L -1 with the detection limit of 5.12 × 10 -13 and 5.85 × 10 -13 g L -1 for malathion and methyl parathion, respectively. More importantly, the presented biosensor considerably improved stability because the electrostatic interaction was converted into covalent bonds by UV irradiation. It is a simple, cheap and stable method for quantitative detection of organophosphorus pesticides, and this method may pave a way for the sensitive, simple detection of different analytes without the need of expensive instrumentation. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Isolation and characterization of bacteria capable of degrading polycyclic aromatic hydrocarbons (PAHs) and organophosphorus pesticides from PAH-contaminated soil in Hilo, Hawaii.

    Science.gov (United States)

    Seo, Jong-Su; Keum, Young-Soo; Harada, Renee M; Li, Qing X

    2007-07-11

    Nineteen bacterial strains were isolated from petroleum-contaminated soil in Hilo, HI, and characterized by two different spray-plated methods, turbidity test in liquid medium, and 16S rRNA gene sequence analysis. Analysis of the soil showed 13 polycyclic aromatic hydrocarbons (PAHs) in a range from 0.6 to 30 mg/kg of dry weight each and 12 PAH metabolites. Five distinct bacterial strains (C3, C4, P1-1, JS14, and JS19b1) selected from preliminary plating and turbidity tests were further tested for PAH degradation through single PAH degradation assay. Strains C3, C4, and P1-1 degraded phenanthrene (40 mg/L) completely during 7 days of incubation. Strain JS14 degraded fluoranthene (40 mg/L) completely during 10 days of incubation. Strain JS19b1 degraded 100% of phenanthrene (40 mg/L) in 7 days, 77% of fluorene (40 mg/L) in 14 days, 97% of fluoranthene (40 mg/L) in 10 days, and 100% of pyrene (40 mg/L) in 14 days. Turbidity tests showed that strains P1-1, JS14, and JS19b1 utilized several organophosphorus pesticides as growth substrate. P1-1 can degrade carbofenothion, chlorfenvinphos, diazinon, fonofos, and pirimiphos-methyl. JS14 can transform chlorfenvinphos and diazinon. JS19b1 can break down diazinon, pirimiphos-methyl, and temephos.

  10. Fluorometric determination of paraoxon in human serum using a gold nanoparticle-immobilized organophosphorus hydrolase and coumarin 1 as a competitive inhibitor

    International Nuclear Information System (INIS)

    Kamelipour, Nahid; Mohsenifar, Afshin; Rahmani-Cherati, Tavoos; Tabatabaei, Meisam; Khoshnevisan, Kamyar; Allameh, Abdolamir; Milani, Majid M.; Etemadikia, Batool; Najavand, Saeid

    2014-01-01

    A dimeric organophosphorus hydrolase (OPH; EC 3.1.8.1; 72 kDa) was isolated from wild-type bacteria, analyzed for its 16s rRNA sequence, purified, and immobilized on gold nanoparticles (AuNPs) to form the transducer part of a biosensor. The isolated strain was identified as Pseudomonas aeruginosa. The AuNPs were characterized by transmission electron microscopy and localized surface plasmon resonance. Covalent binding of OPH to the AuNPs was confirmed by spectrophotometry, enzymatic activity assays, and FTIR spectroscopy. Coumarin 1, a competitive inhibitor of OPH, was used as a fluorogenic probe. The bioconjugates quench the emission of coumarin 1 upon binding, but the addition of paraoxon results in an enhancement of fluorescence that is directly proportional to the concentration of paraoxon. The gold-OPH conjugates were then used to determine paraoxon in serum samples spiked with varying levels of paraoxon. The method works in the 50 to 1,050 nM concentration range, has a low standard deviation (with a CV of 5.7–11 %), and a detection limit as low as 5 × 10 −11 M. (author)

  11. One-step electrochemical deposition of a graphene-ZrO2 nanocomposite: Preparation, characterization and application for detection of organophosphorus agents

    Energy Technology Data Exchange (ETDEWEB)

    Du, Dan; Liu, Juan; Zhang, Xiao-Yan; Cui, Xiao-Li; Lin, Yuehe

    2011-04-27

    This paper described the preparation, characterization, and electrochemical properties of a graphene-ZrO2 nanocomposite (GZN) and its application for both the enrichment and detection of methyl parathion (MP). GZN was fabricated using electrochemical deposition and characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), which showed the successful formation of nanocomposites. Due to the strong affinity to the phosphoric group and the fast electron-transfer kinetics of GZN, both the extraction and electrochemical detection of organophosphorus (OP) agents at the same GZN modified electrochemical sensor was possible. The combination of solid-phase extraction and stripping voltammetric analysis allowed fast, sensitive, and selective determination of MP in garlic samples. The stripping response was highly linear over the MP concentrations ranging from 0.5 ng mL-1 to 100 ng mL-1, with a detection limit of 0.1 ng mL-1. This new nanocomposite-based electrochemical sensor provides an opportunity to develop a field-deployable, sensitive, and quantitative method for monitoring exposure to OPs.

  12. Sensitive Detection of Organophosphorus Pesticides in Medicinal Plants Using Ultrasound-Assisted Dispersive Liquid-Liquid Microextraction Combined with Sweeping Micellar Electrokinetic Chromatography.

    Science.gov (United States)

    Wei, Jin-Chao; Hu, Ji; Cao, Ji-Liang; Wan, Jian-Bo; He, Cheng-Wei; Hu, Yuan-Jia; Hu, Hao; Li, Peng

    2016-02-03

    A simple, rapid, and sensitive method using ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME) combined with sweeping micellar electrokinetic chromatography (sweeping-MEKC) has been developed for the determination of nine organophosphorus pesticides (chlorfenvinphos, parathion, quinalphos, fenitrothion, azinphos-ethyl, parathion-methyl, fensulfothion, methidathion, and paraoxon). The important parameters that affect the UA-DLLME and sweeping efficiency were investigated. Under the optimized conditions, the proposed method provided 779.0-6203.5-fold enrichment of the nine pesticides compared to the normal MEKC method. The limits of detection ranged from 0.002 to 0.008 mg kg(-1). The relative standard deviations of the peak area ranged from 1.2 to 6.5%, indicating the good repeatability of the method. Finally, the developed UA-DLLME-sweeping-MEKC method has been successfully applied to the analysis of the investigated pesticides in several medicinal plants, including Lycium chinense, Dioscorea opposite, Codonopsis pilosula, and Panax ginseng, indicating that this method is suitable for the determination of trace pesticide residues in real samples with complex matrices.

  13. An absorbing microwave micro-solid-phase extraction device used in non-polar solvent microwave-assisted extraction for the determination of organophosphorus pesticides.

    Science.gov (United States)

    Wang, Ziming; Zhao, Xin; Xu, Xu; Wu, Lijie; Su, Rui; Zhao, Yajing; Jiang, Chengfei; Zhang, Hanqi; Ma, Qiang; Lu, Chunmei; Dong, Deming

    2013-01-14

    A single-step extraction-cleanup method, including microwave-assisted extraction (MAE) and micro-solid-phase extraction (μ-SPE), was developed for the extraction of ten organophosphorus pesticides in vegetable and fruit samples. Without adding any polar solvent, only one kind of non-polar solvent (hexane) was used as extraction solvent in the whole extraction step. Absorbing microwave μ-SPE device, was prepared by packing activated carbon with microporous polypropylene membrane envelope, and used as not only the sorbent in μ-SPE, but also the microwave absorption medium. Some experimental parameters effecting on extraction efficiency was investigated and optimized. 1.0 g of sample, 8 mL of hexane and three absorbing microwave μ-SPE devices were added in the microwave extraction vessel, the extraction was carried out under 400 W irradiation power at 60°C for 10 min. The extracts obtained by MAE-μ-SPE were directly analyzed by GC-MS without any clean-up process. The recoveries were in the range of 93.5-104.6%, and the relative standard deviations were lower than 8.7%. Copyright © 2012 Elsevier B.V. All rights reserved.

  14. A Mobile-Based High Sensitivity On-Field Organophosphorus Compounds Detecting System for IoT-Based Food Safety Tracking

    Directory of Open Access Journals (Sweden)

    Han Jin

    2017-01-01

    Full Text Available A mobile-based high sensitivity absorptiometer is presented to detect organophosphorus (OP compounds for Internet-of-Things based food safety tracking. This instrument consists of a customized sensor front-end chip, LED-based light source, low power wireless link, and coin battery, along with a sample holder packaged in a recycled format. The sensor front-end integrates optical sensor, capacitive transimpedance amplifier, and a folded-reference pulse width modulator in a single chip fabricated in a 0.18 μm 1-poly 5-metal CMOS process and has input optical power dynamic range of 71 dB, sensitivity of 3.6 nW/cm2 (0.77 pA, and power consumption of 14.5 μW. Enabled by this high sensitivity sensor front-end chip, the proposed absorptiometer has a small size of 96 cm3, with features including on-field detection and wireless communication with a mobile. OP compound detection experiments of the handheld system demonstrate a limit of detection (LOD of 0.4 μmol/L, comparable to that of a commercial spectrophotometer. Meanwhile, an android-based application (APP is presented which makes the absorptiometer access to the Internet-of-Things (IoT.

  15. Ascorbic acid surface modified TiO₂-thin layers as a fully integrated analysis system for visual simultaneous detection of organophosphorus pesticides.

    Science.gov (United States)

    Li, Shunxing; Liang, Wenjie; Zheng, Fengying; Lin, Xiaofeng; Cai, Jiabai

    2014-11-06

    TiO₂ photocatalysis and colorimetric detection are coupled with thin layer chromatography (TLC) for the first time to develop a fully integrated analysis system. Titania@polystyrene hybrid microspheres were surface modified with ascorbic acid, denoted AA-TiO₂@PS, and used as the stationary phase for TLC. Because the affinity between AA-TiO₂@PS and organophosphorus pesticides (OPs) was different for different species of OPs (including chlopyrifos, malathion, parathion, parathion-methyl, and methamidophos), OPs could be separated simultaneously by the mobile phase in 12.0 min with different Rf values. After surface modification, the UV-vis wavelength response range of AA-TiO₂@PS was expanded to 650 nm. Under visible-light irradiation, all of the OPs could be photodegraded to PO₄(3-) in 25.0 min. Based on the chromogenic reaction between PO₄(3-) and chromogenic agents (ammonium molybdate and ascorbic acid), OPs were quantified from color intensity images using a scanner in conjunction with image processing software. So, AA-TiO₂@PS was respectively used as the stationary phase of TLC for efficient separation of OPs, as a photocatalyst for species transformation of phosphorus, and as a colorimetric probe for on-field simultaneous visual detection of OPs in natural water. Linear calibration curves for each OP ranged from 19.3 nmol P L(-1) to 2.30 μmol P L(-1). This integrated analysis system was simple, inexpensive, easy to operate, and sensitive.

  16. In vitro skin permeation and decontamination of the organophosphorus pesticide paraoxon under various physical conditions--evidence for a wash-in effect.

    Science.gov (United States)

    Misik, Jan; Pavlikova, Ruzena; Josse, Denis; Cabal, Jiri; Kuca, Kamil

    2012-09-01

    Misuse of various chemicals, such as chemical warfare agents, industrial chemicals or pesticides during warfare or terrorists attacks requires adequate protection. Thus, development and evaluation of novel decontamination dispositives and techniques are needed. In this study, in vitro permeation and decontamination of a potentially hazardous compound paraoxon, an active metabolite of organophosphorus pesticide parathion, was investigated. Skin permeation and decontamination experiments were carried out in modified Franz diffusion cells. Pig skin was used as a human skin model. Commercially produced detergent-based washing solutions FloraFree(™) and ArgosTM were used as decontamination means. The experiments were done under "warm", "cold", "dry" and "wet" skin conditions in order to determine an effect of various physical conditions on skin permeation of paraoxon and on a subsequent decontamination process. There was no significant difference in skin permeation of paraoxon under warm, cold and dry conditions, whereas wet conditions provided significantly higher permeation rates. In the selected conditions, decontamination treatments performed 1 h after a skin exposure did not decrease the agent volume that permeated through the skin. An exception were wet skin conditions with non-significant decontamination efficacy 18 and 28% for the FloraFree(™) and Argos(™) treatment, respectively. In contrast, the skin permeation of paraoxon under warm, cold and dry conditions increased up to 60-290% following decontamination compared to non-decontaminated controls. This has previously been described as a skin wash-in effect.

  17. Graphene Quantum Dots/Eggshell Membrane Composite as a Nano-sorbent for Preconcentration and Determination of Organophosphorus Pesticides by High-Performance Liquid Chromatography

    Directory of Open Access Journals (Sweden)

    Vahideh Abdollahi

    2017-10-01

    Full Text Available In this study graphene quantum dots/eggshell membrane nanocomposite (GQDS/ESM is prepared and used as an efficient solid-phase extraction (SPE sorbent for preconcentration of organophosphorus pesticides (OPPs from aqueous solutions. The retained analytes on the sorbent are stripped by acetonitrile and subsequently are determined by high-performance liquid chromatography. Various parameters affecting the extraction efficiency of OPPs on the GQDS/ESM, such as solution pH, amount of nano-sorbent, sample loading flow rate, elution conditions and sample volume are investigated. The results demonstrated that the proposed method has a wide dynamic linear range (0.05–100 ng mL-1, good linearity (R2>0.997 and low detection limits (0.006-0.32 ng mL-1. High enrichment factors are achieved ranging from 110 to 140. In the optimum experimental conditions, the established method is successfully applied for the determination of OPPs in spiked water samples (well, tap, shaft and canal and apple juice. Satisfactory recovery results show that the sample matrices under consideration do not significantly affect the extraction process.

  18. Efficient Degradation of Malathion in the Presence of Detergents Using an Engineered Organophosphorus Hydrolase Highly Expressed by Pichia pastoris without Methanol Induction.

    Science.gov (United States)

    Bai, Yun-Peng; Luo, Xiao-Jing; Zhao, Yu-Lian; Li, Chun-Xiu; Xu, Dian-Sheng; Xu, Jian-He

    2017-10-18

    The biodegradation of pesticides by organophosphorus hydrolases (OPHs) requires an efficient enzyme production technology in industry. Herein, a Pichia pastoris strain was constructed for the extracellular expression of PoOPH M9 , an engineered malathion-degrading enzyme. After optimization, the maximum titer and yield of fermentation reached 50.8 kU/L and 4.1 g protein /L after 3 days, with the highest space-time yield (STY) reported so far, 640 U L -1 h -1 . PoOPH M9 displayed its high activity and stability in the presence of 0.1% (w/w) plant-derived detergent. Only 0.04 mg/mL enzyme could completely remove 0.15 mM malathion in aqueous solution within 20 min. Furthermore, 12 μmol malathion on apples and cucumbers surfaces was completely removed by 0.05 mg/mL PoOPH M9 in tap water after 35 min washing. The efficient production of the highly active PoOPH M9 has cleared a major barrier to biodegradation of pesticide residues in food industry.

  19. Aging Brain, Aging Mind.

    Science.gov (United States)

    Selkoe, Dennis J.

    1992-01-01

    Discusses the aging process related to physical changes of the human neural structure involved in learning, memory, and reasoning. Presents evidence that indicates such alterations do not necessarily signal the decline in cognitive function. Vignettes provide images of brain structures involved in learning, memory, and reasoning; hippocampal…

  20. Inhibition of lactation.

    Science.gov (United States)

    Llewellyn-Jones, D

    1975-01-01

    The mechanism and hormonal regulation of lactation is explained and illustrated with a schematic representation. Circulating estrogen above a critical amount seems to be the inhibitory factor controlling lactation during pregnancy. Once delivery occurs, the level of estrogen falls, that of prolactin rises, and lactation begins. Nonsuckling can be used to inhibit lactation. Estrogens can also be used to inhibit lactation more quickly and with less pain. The reported association between estrogens and puerperal thromboembolism cannot be considered conclusive due to defects in the reporting studies. There is no reason not to use estrogens in lactation inhibition except for women over 35 who experienced a surgical delivery. Alternative therapy is available for these women. The recently-developed drug, brom-ergocryptine, may replace other methods of lactation inhibition.

  1. Sporadic inclusion-body myositis: conformational multifactorial ageing-related degenerative muscle disease associated with proteasomal and lysosomal inhibition, endoplasmic reticulum stress, and accumulation of amyloid-β42 oligomers and phosphorylated tau.

    Science.gov (United States)

    Askanas, Valerie; Engel, W King

    2011-04-01

    The pathogenesis of sporadic inclusion-body myositis (s-IBM), the most common muscle disease of older persons, is complex and multifactorial. Both the muscle fiber degeneration and the mononuclear-cell inflammation are components of the s-IBM pathology, but how each relates to the pathogenesis remains unsettled. We consider that the intramuscle fiber degenerative component plays the primary and the major pathogenic role leading to muscle fiber destruction and clinical weakness. In this article we review the newest research advances that provide a better understanding of the s-IBM pathogenesis. Cellular abnormalities occurring in s-IBM muscle fibers are discussed, including: several proteins that are accumulated in the form of aggregates within muscle fibers, including amyloid-β42 and its oligomers, and phosphorylated tau in the form of paired helical filaments, and we consider their putative detrimental influence; cellular mechanisms leading to protein misfolding and aggregation, including evidence of their inadequate disposal; pathogenic importance of endoplasmic reticulum stress and the unfolded protein response demonstrated in s-IBM muscle fibers; and decreased deacetylase activity of SIRT1. All these factors are combined with, and perhaps provoked by, an ageing intracellular milieu. Also discussed are the intriguing phenotypic similarities between s-IBM muscle fibers and the brains of Alzheimer and Parkinson's disease patients, the two most common neurodegenerative diseases associated with ageing. Muscle biopsy diagnostic criteria are also described and illustrated. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  2. High molecular weight polysaccharide that binds and inhibits virus

    Science.gov (United States)

    Konowalchuk, Thomas W

    2014-01-14

    This invention provides a high molecular weight polysaccharide capable of binding to and inhibiting virus and related pharmaceutical formulations and methods on inhibiting viral infectivity and/or pathogenicity, as well as immunogenic compositions. The invention further methods of inhibiting the growth of cancer cells and of ameliorating a symptom of aging. Additionally, the invention provides methods of detecting and/or quantifying and/or isolating viruses.

  3. High molecular weight polysaccharide that binds and inhibits virus

    Energy Technology Data Exchange (ETDEWEB)

    Konowalchuk, Thomas W.; Konowalchuk, Jack

    2017-07-18

    This invention provides a high molecular weight polysaccharide capable of binding to and inhibiting virus and related pharmaceutical formulations and methods of inhibiting viral infectivity and/or pathogenicity, as well as immunogenic compositions. The invention further includes methods of inhibiting the growth of cancer cells and of ameliorating a symptom of aging. Additionally, the invention provides methods of detecting and/or quantifying and/or isolating viruses.

  4. Chlorpyrifos and chlorpyrifos-oxon inhibit axonal growth by interfering with the morphogenic activity of acetylcholinesterase

    International Nuclear Information System (INIS)

    Yang Dongren; Howard, Angela; Bruun, Donald; Ajua-Alemanj, Mispa; Pickart, Cecile; Lein, Pamela J.

    2008-01-01

    A primary role of acetylcholinesterase (AChE) is regulation of cholinergic neurotransmission by hydrolysis of synaptic acetylcholine. In the developing nervous system, however, AChE also functions as a morphogenic factor to promote axonal growth. This raises the question of whether organophosphorus pesticides (OPs) that are known to selectively bind to and inactivate the enzymatic function of AChE also interfere with its morphogenic function to perturb axonogenesis. To test this hypothesis, we exposed primary cultures of sensory neurons derived from embryonic rat dorsal root ganglia (DRG) to chlorpyrifos (CPF) or its oxon metabolite (CPFO). Both OPs significantly decreased axonal length at concentrations that had no effect on cell viability, protein synthesis or the enzymatic activity of AChE. Comparative analyses of the effects of CPF and CPFO on axonal growth in DRG neurons cultured from AChE nullizygous (AChE -/- ) versus wild type (AChE +/+ ) mice indicated that while these OPs inhibited axonal growth in AChE +/+ DRG neurons, they had no effect on axonal growth in AChE -/- DRG neurons. However, transfection of AChE -/- DRG neurons with cDNA encoding full-length AChE restored the wild type response to the axon inhibitory effects of OPs. These data indicate that inhibition of axonal growth by OPs requires AChE, but the mechanism involves inhibition of the morphogenic rather than enzymatic activity of AChE. These findings suggest a novel mechanism for explaining not only the functional deficits observed in children and animals following developmental exposure to OPs, but also the increased vulnerability of the developing nervous system to OPs

  5. Possible mechanisms for sensitivity to organophosphorus and carbamate insecticides in eastern screech-owls and American kestrels.

    Science.gov (United States)

    Vyas, N B; Thiele, L A; Garland, S C

    1998-07-01

    Effects of a single dietary exposure to fenthion and carbofuran on the survival, feeding behavior and brain ChE activity of eastern screech-owls, Otus asio and American kestrels, Falco sparverius, were evaluated. Birds were exposed to fenthion (23.6-189.0 ppm) or carbofuran (31.7-253.6 ppm) via meatballs. Carbofuran-exposed owls ate either or = 80% of the meatball whereas all kestrels ate meatball before exhibiting acute signs of toxicity. Fenthion-exposed owls and kestrels displayed a wide spectrum of meatball consumption (< 10-100%). Significant brain ChE inhibition was observed in dead and surviving kestrels exposed to fenthion and carbofuran and dead owls exposed to fenthion (P < 0.0001). Brain ChE activity of owls exposed to carbofuran that survived was not different from that of controls (P = 0.25). Data suggest: (1) slow feeding on a carbamate-contaminated item may provide limited protection from the toxicity of the chemical at certain rates of exposure; (2) the degree of ChE inhibition at neuromuscular junctions may be critical in determining the sensitivity of a species to a carbamate insecticide; (3) sensitivity may be a function of the ChE affinity for the carbamate inhibitor; and (4) the importance of neuromuscular junction ChE depression in determining the sensitivity of an animal may be species-specific.

  6. Possible mechanisms for sensitivity to organophosphorus and carbamate insecticides in eastern screech-owls and American kestrels

    Science.gov (United States)

    Vyas, N.B.; Thiele, L.A.; Garland, S.C.

    1998-01-01

    Effects of a single dietary exposure to fenthion and carbofuran on the survival, feeding behavior and brain ChE activity of eastern screech-owls, Otus asio and American kestrels, Falco sparverius, were evaluated. Birds were exposed to fenthion (23.6–189.0 ppm) or carbofuran (31.7–253.6 ppm) via meatballs. Carbofuran-exposed owls ate either ≤10% or ≥80% of the meatball whereas all kestrels ate ≤10% of the meatball before exhibiting acute signs of toxicity. Fenthion-exposed owls and kestrels displayed a wide spectrum of meatball consumption (<10–100%). Significant brain ChE inhibition was observed in dead and surviving kestrels exposed to fenthion and carbofuran and dead owls exposed to fenthion (P<0.0001). Brain ChE activity of owls exposed to carbofuran that survived was not different from that of controls (P=0.25). Data suggest: (1) slow feeding on a carbamate-contaminated item may provide limited protection from the toxicity of the chemical at certain rates of exposure; (2) the degree of ChE inhibition at neuromuscular junctions may be critical in determining the sensitivity of a species to a carbamate insecticide; (3) sensitivity may be a function of the ChE affinity for the carbamate inhibitor; and (4) the importance of neuromuscular junction ChE depression in determining the sensitivity of an animal may be species-specific.

  7. effect of interaction of praziquantel and an organophosphorus pesticide on some biochemical parameters in murine schistosomiasis mansoni

    International Nuclear Information System (INIS)

    Abd-El Menem, H.A.

    2003-01-01

    in egypt schistosomiasis is still a major public health problem and PZQ is the drug of choice for its treatment, whereas DZN is globally used as pesticide for controlling pests. they adversely affect the environment . therefore, this investigation aimed to study the effect of 1/20 LD 5 0 DZN given orally to healthy and S. mansoni infected mice, for 5 successive days up to 9 and 17 weeks coupled with a therapeutic dose (2 x 500 mg/kg b wt) of PZQ , 2 weeks before sacrificing . the results showed that the different treatments significantly reduced the activity of liver ALT. the highest inhibition was recorded in the infected-DZN - PZQ group at week 9. the maximum inhibition of brain ACHE activity was noticed in DZN-PZQ treated group after 9 and 17 weeks. although,the different treatments did not significantly affect the levels of plasma TP,ALB,G,and A/G ratio, significant differences were revealed from the G- fractions α 1 , α 2 , β 1 , β 2 and γ in addition to plasma ceruloplasmin

  8. Aging Education: A Worldwide Imperative

    Science.gov (United States)

    McGuire, Sandra L.

    2017-01-01

    Life expectancy is increasing worldwide. Unfortunately, people are generally not prepared for this long life ahead and have ageist attitudes that inhibit maximizing the "longevity dividend" they have been given. Aging education can prepare people for life's later years and combat ageism. It can reimage aging as a time of continued…

  9. Cohort-Sequential Study of Conflict Inhibition during Middle Childhood

    Science.gov (United States)

    Rollins, Leslie; Riggins, Tracy

    2017-01-01

    This longitudinal study examined developmental changes in conflict inhibition and error correction in three cohorts of children (5, 7, and 9 years of age). At each point of assessment, children completed three levels of Luria's tapping task (1980), which requires the inhibition of a dominant response and maintenance of task rules in working…

  10. Cognitive Inhibition in Students with and without Dyslexia and Dyscalculia

    Science.gov (United States)

    Wang, Li-Chih; Tasi, Hung-Ju; Yang, Hsien-Ming

    2012-01-01

    The present study presents a comparison of the cognitive inhibition abilities of dyslexic, dyscalculic, and control students. The participants were 45 dyslexic students, 45 dyscalculic students, and 45 age-, gender-, and IQ-matched control students. The major evaluation tools included six cognitive inhibition tasks which were restructured during…

  11. Determinação de pesticidas organofosforados em água usando microextração em fase sólida e CGAR-EM Determination of organophosphorus pesticides in water using SPME-GC-MS

    Directory of Open Access Journals (Sweden)

    Fernando Carvalho Silva

    1999-04-01

    Full Text Available Solid-phase microextraction (SPME has been applied to direct extraction of 11 organophosphorus pesticides in water using a 100 mm fiber polydimethylsiloxane. The method was evaluated with respect time of exposure, detection limits (LODs, linearity and precision. The detection limits (S/N = 3 depend of each pesticide and varie about ng/L levels. The linearity was satisfactory with coefficients of correlation usually greater than 0.993. The precision of the method was determined by extraction from 4.0 mg/L aqueous standard with coefficients of variation between 5.7 to 17.2%.

  12. Acute toxicity and cholinesterase inhibition of the nematicide ethoprophos in larvae of gar Atractosteus tropicus (Semionotiformes: Lepisosteidae

    Directory of Open Access Journals (Sweden)

    Freylan Mena Torres

    2012-03-01

    Full Text Available Biomarkers are a widely applied approach in environmental studies. Analyses of cholinesterase (ChE, glutathione S-transferase (GST and lipid peroxidation (LPO are biomarkers that can provide information regarding early effects of pollutants at different biochemical levels on an organism. The aim of this study was to evaluate the biomarker approach on a Costa Rican native and relevant species. For this, larvae of gar (Atractosteus tropicus were exposed to the organophosphorus nematicide, ethoprophos. Acute (96hr exposure was conducted with pesticide concentrations ranging from 0.1μg/L to 1 500μg/L. The 96hr LC50 calculated was 859.7μg/L. After exposure, three biomarkers (ChE, GST and LPO were analyzed in fish that survived the acute test. The lowest observed effect concentration (LOEC regarding ChE activity inhibition was 50μg/L. This concentration produced a significant inhibition (p0.05 in GST activity and LPO were observed in A. tropicus larvae after exposure to ethoprophos.

  13. Ascorbic acid surface modified TiO2-thin layers as a fully integrated analysis system for visual simultaneous detection of organophosphorus pesticides

    Science.gov (United States)

    Li, Shunxing; Liang, Wenjie; Zheng, Fengying; Lin, Xiaofeng; Cai, Jiabai

    2014-11-01

    TiO2 photocatalysis and colorimetric detection are coupled with thin layer chromatography (TLC) for the first time to develop a fully integrated analysis system. Titania@polystyrene hybrid microspheres were surface modified with ascorbic acid, denoted AA-TiO2@PS, and used as the stationary phase for TLC. Because the affinity between AA-TiO2@PS and organophosphorus pesticides (OPs) was different for different species of OPs (including chlopyrifos, malathion, parathion, parathion-methyl, and methamidophos), OPs could be separated simultaneously by the mobile phase in 12.0 min with different Rf values. After surface modification, the UV-vis wavelength response range of AA-TiO2@PS was expanded to 650 nm. Under visible-light irradiation, all of the OPs could be photodegraded to PO43- in 25.0 min. Based on the chromogenic reaction between PO43- and chromogenic agents (ammonium molybdate and ascorbic acid), OPs were quantified from color intensity images using a scanner in conjunction with image processing software. So, AA-TiO2@PS was respectively used as the stationary phase of TLC for efficient separation of OPs, as a photocatalyst for species transformation of phosphorus, and as a colorimetric probe for on-field simultaneous visual detection of OPs in natural water. Linear calibration curves for each OP ranged from 19.3 nmol P L-1 to 2.30 μmol P L-1. This integrated analysis system was simple, inexpensive, easy to operate, and sensitive.TiO2 photocatalysis and colorimetric detection are coupled with thin layer chromatography (TLC) for the first time to develop a fully integrated analysis system. Titania@polystyrene hybrid microspheres were surface modified with ascorbic acid, denoted AA-TiO2@PS, and used as the stationary phase for TLC. Because the affinity between AA-TiO2@PS and organophosphorus pesticides (OPs) was different for different species of OPs (including chlopyrifos, malathion, parathion, parathion-methyl, and methamidophos), OPs could be separated

  14. Inhibition of the human liver microsomal and human cytochrome P450 1A2 and 3A4 metabolism of estradiol by deployment-related and other chemicals.

    Science.gov (United States)

    Usmani, Khawja A; Cho, Taehyeon M; Rose, Randy L; Hodgson, Ernest

    2006-09-01

    Cytochromes P450 (P450s) are major catalysts in the metabolism of xenobiotics and endogenous substrates such as estradiol (E2). It has previously been shown that E2 is predominantly metabolized in humans by CYP1A2 and CYP3A4 with 2-hydroxyestradiol (2-OHE2) the major metabolite. This study examines effects of deployment-related and other chemicals on E2 metabolism by human liver microsomes (HLM) and individual P450 isoforms. Kinetic studies using HLM, CYP3A4, and CYP1A2 showed similar affinities (Km) for E2 with respect to 2-OHE2 production. Vmax and CLint values for HLM are 0.32 nmol/min/mg protein and 7.5 microl/min/mg protein; those for CYP3A4 are 6.9 nmol/min/nmol P450 and 291 microl/min/nmol P450; and those for CYP1A2 are 17.4 nmol/min/nmol P450 and 633 microl/min/nmol P450. Phenotyped HLM use showed that individuals with high levels of CYP1A2 and CYP3A4 have the greatest potential to metabolize E2. Preincubation of HLM with a variety of chemicals, including those used in military deployments, resulted in varying levels of inhibition of E2 metabolism. The greatest inhibition was observed with organophosphorus compounds, including chlorpyrifos and fonofos, with up to 80% inhibition for 2-OHE2 production. Carbaryl, a carbamate pesticide, and naphthalene, a jet fuel component, inhibited ca. 40% of E2 metabolism. Preincubation of CYP1A2 with chlorpyrifos, fonofos, carbaryl, or naphthalene resulted in 96, 59, 84, and 87% inhibition of E2 metabolism, respectively. Preincubation of CYP3A4 with chlorpyrifos, fonofos, deltamethrin, or permethrin resulted in 94, 87, 58, and 37% inhibition of E2 metabolism. Chlorpyrifos inhibition of E2 metabolism is shown to be irreversible.

  15. Evaluations of in vitro metabolism, drug-drug interactions mediated by reversible and time-dependent inhibition of CYPs, and plasma protein binding of MMB4 DMS.

    Science.gov (United States)

    Hong, S Peter; Lusiak, Bozena D; Burback, Brian L; Johnson, Jerry D

    2013-01-01

    1,1'-Methylenebis[4-[(hydroxyimino)methyl]-pyridinium] (MMB4) dimethanesulfonate (DMS) is a bisquaternary pyridinium aldoxime that reactivates acetylcholinesterase inhibited by organophosphorus nerve agent. Drug metabolism and plasma protein binding for MMB4 DMS were examined using various techniques and a wide range of species. When (14)C-MMB4 DMS was incubated in liver microsomes, 4-pyridine aldoxime (4-PA) and an additional metabolite were detected in all species tested. Identity of the additional metabolite was postulated to be isonicotinic acid (INA) based on liquid chromatography with a tandem mass spectrometry analysis, which was confirmed by comparison with authentic INA. Formation of INA was dependent on species, with the highest level found in monkey liver microsomes. The MMB4 DMS exhibited reversible inhibition in a concentration-dependent manner toward cytochrome P450 1A2 (CYP1A2), CYP2C9, CYP2C19, CYP2D6, and CYP3A4 in human liver microsomes showing the highest inhibition for CYP2D6. Human recombinant CYPs were used to evaluate inhibitory curves more adequately and determine detailed kinetic constants for reversible inhibition and potential time-dependent inhibition (TDI). The MMB4 DMS exhibited reversible inhibition toward human-recombinant CYP2D6 with an inhibition constant (K i) value of 66.6 µmol/L. Based on the k inact/K I values, MMB4 DMS was found to exhibit the most potent TDI toward CYP2D6. The MMB4 DMS at 5 different concentrations was incubated in plasma for 5 hours using an equilibrium dialysis device. For all species tested, there were no concentration-dependent changes in plasma protein binding, ranging from 10% to 17%. These results suggest that MMB4 was not extensively bound to plasma protein, and there were no overt species-related differences in the extent of MMB4 bound to plasma protein.

  16. Monocrotophos, an organophosphorus insecticide, disrupts the expression of HpNetrin and its receptor neogenin during early development in the sea urchin (Hemicentrotus pulcherrimus).

    Science.gov (United States)

    Zhang, Xiaona; Xu, Lei; Tian, Hua; Wang, Cuicui; Wang, Wei; Ru, Shaoguo

    2017-09-01

    Netrins, chemotropic guidance cues, can guide the extension of serotonergic axons by binding to netrin receptors during neural development. However, little is known about whether disruption of netrin signaling is involved in the mechanisms by which organophosphorus pesticides affect serotonergic nervous system (SNS) development. In this study, we evaluated the effects of the pesticide monocrotophos (MCP) on the expression patterns of HpNetrin and its receptor neogenin as well as on the intracellular calcium ion (Ca 2+ ) levels in Hemicentrotus pulcherrimus (sea urchin) by exposing fertilized embryos to 0, 0.01, 0.10, and 1.00mg/L MCP. The results showed that MCP disrupted HpNetrin and neogenin expression at different developmental stages in H. pulcherrimus and that Ca 2+ appeared to be involved in the MCP-induced developmental neurotoxicity. Specifically, the lower concentrations of MCP elevated HpNetrin and neogenin transcription, resulting in higher intracellular Ca 2+ levels during the early developmental stages in the sea urchin; this may affect netrin-directed cell migration/axon extension and subsequently disrupt serotonergic axon branching and synapse formation. In contrast, 1.00mg/L MCP exhibited an inhibitory effect on HpNetrin and neogenin transcription. This finding implies that the regulatory roles of these factors may be diminished during early development, thereby causing developmental defects in the sea urchin. Collectively, our results provide a basis for exploring the involvement of netrin and neogenin in the organophosphate-induced disruption of the SNS during development. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Rapid and sensitive suspension array for multiplex detection of organophosphorus pesticides and carbamate pesticides based on silica–hydrogel hybrid microbeads

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xuan [Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, Jiangsu (China); Mu, Zhongde; Shangguan, Fengqi [State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, Jiangsu (China); Liu, Ran; Pu, Yuepu [Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, Jiangsu (China); Yin, Lihong, E-mail: lhyin@seu.edu.cn [Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, Jiangsu (China)

    2014-05-01

    Highlights: • Silica–hydrogel hybrid microbeads were used to develop suspension array. • The results in detecting pesticides agree well with those from LC–MS/MS. • The method showed the good capability for multiplex analysis of pesticides residues. - Abstract: A technique for multiplex detection of organophosphorus pesticides and carbamate pesticides has been developed using a suspension array based on silica–hydrogel hybrid microbeads (SHHMs). The main advantage of SHHMs, which consist of both silica and hydrogel materials, is that they not only could be distinguished by their characteristic reflection peak originating from the stop-band of the photonic crystal but also have low non-specific adsorption of proteins. Using fluorescent immunoassay, the LODs for fenitrothion, chlorpyrifos-methyl, fenthion, carbaryl and metolcarb were measured to be 0.02 ng/mL, 0.012 ng/mL, 0.04 ng/mL, 0.05 ng/mL and 0.1 ng/mL, respectively, all of which are much lower than the maximum residue limits, as reported in the European Union pesticides database. All the determination coefficients for these five pesticides were greater than 0.99, demonstrating excellent correlations. The suspension array was specific and had no significant cross-reactivity with other chemicals. The results for the detection of pesticide residues collected from agricultural samples using this method agree well with those from liquid chromatography–tandem mass spectrometry. Our results showed that this simple method is suitable for simultaneous detection of these five pesticides residues in fruits and vegetables.

  18. Rapid and sensitive suspension array for multiplex detection of organophosphorus pesticides and carbamate pesticides based on silica–hydrogel hybrid microbeads

    International Nuclear Information System (INIS)

    Wang, Xuan; Mu, Zhongde; Shangguan, Fengqi; Liu, Ran; Pu, Yuepu; Yin, Lihong

    2014-01-01

    Highlights: • Silica–hydrogel hybrid microbeads were used to develop suspension array. • The results in detecting pesticides agree well with those from LC–MS/MS. • The method showed the good capability for multiplex analysis of pesticides residues. - Abstract: A technique for multiplex detection of organophosphorus pesticides and carbamate pesticides has been developed using a suspension array based on silica–hydrogel hybrid microbeads (SHHMs). The main advantage of SHHMs, which consist of both silica and hydrogel materials, is that they not only could be distinguished by their characteristic reflection peak originating from the stop-band of the photonic crystal but also have low non-specific adsorption of proteins. Using fluorescent immunoassay, the LODs for fenitrothion, chlorpyrifos-methyl, fenthion, carbaryl and metolcarb were measured to be 0.02 ng/mL, 0.012 ng/mL, 0.04 ng/mL, 0.05 ng/mL and 0.1 ng/mL, respectively, all of which are much lower than the maximum residue limits, as reported in the European Union pesticides database. All the determination coefficients for these five pesticides were greater than 0.99, demonstrating excellent correlations. The suspension array was specific and had no significant cross-reactivity with other chemicals. The results for the detection of pesticide residues collected from agricultural samples using this method agree well with those from liquid chromatography–tandem mass spectrometry. Our results showed that this simple method is suitable for simultaneous detection of these five pesticides residues in fruits and vegetables

  19. A simple solvothermal process for fabrication of a metal-organic framework with an iron oxide enclosure for the determination of organophosphorus pesticides in biological samples.

    Science.gov (United States)

    Zhang, Suling; Jiao, Zhe; Yao, Weixuan

    2014-12-05

    An active magnetic metal-organic framework (MOF) hybrid material was prepared using a novel in situ solvothermal method in the presence of magnetite (Fe3O4) particles, that holds much promise for large-scale synthesis. MIL-101(Fe), an iron terephthalate with pore structure and high resistance to water and common solvents, was functionalized as a model with superparamagnetic qualities, using Fe3O4. The electrostatic interaction between Fe3O4 and metal ions was thereby used to chemically stabilize magnetic nanoparticles, and thus MOF crystals were uniformly enclosed by Fe3O4 to form a homogeneous magnetic product identified as a Fe3O4/MIL-101 composite. This hybrid material with magnetic susceptibility but with the lowest possible loading amount of Fe3O4 was examined, and its potential application for magnetic solid-phase extraction of six organophosphorus pesticides (OPPs) from human hair and urine samples, followed by gas chromatography analysis, was assessed. The main effect parameters including solution ionic strength, desorption solvent, extraction time and desorption time were investigated in sequence. Under optimized conditions, this method showed low detection limits (0.21-2.28 ng/mL), wide linearity, and good precision (1.8-8.7% for intra-day, 2.9-9.4% for inter-day). The matrix interference produced by hair or urine could be effectively eliminated using this method, and satisfactory recoveries of the spiked samples were 76.8-94.5% and 74.9-92.1%, respectively, indicating that the Fe3O4/MIL-101 sorbents are feasible for the analysis of trace analytes from biological samples. Copyright © 2014. Published by Elsevier B.V.

  20. An absorbing microwave micro-solid-phase extraction device used in non-polar solvent microwave-assisted extraction for the determination of organophosphorus pesticides

    International Nuclear Information System (INIS)

    Wang Ziming; Zhao Xin; Xu Xu; Wu Lijie; Su Rui; Zhao Yajing; Jiang Chengfei; Zhang Hanqi; Ma Qiang; Lu Chunmei; Dong Deming

    2013-01-01

    Highlights: ► An absorbing microwave μ-SPE device packed with activated carbon was used. ► Absorbing microwave μ-SPE device was made and used to enrich the analytes. ► Absorbing microwave μ-SPE device was made and used to heat samples directly. ► MAE-μ-SPE was applied to the extraction of OPPs with non-polar solvent only. - Abstract: A single-step extraction-cleanup method, including microwave-assisted extraction (MAE) and micro-solid-phase extraction (μ-SPE), was developed for the extraction of ten organophosphorus pesticides in vegetable and fruit samples. Without adding any polar solvent, only one kind of non-polar solvent (hexane) was used as extraction solvent in the whole extraction step. Absorbing microwave μ-SPE device, was prepared by packing activated carbon with microporous polypropylene membrane envelope, and used as not only the sorbent in μ-SPE, but also the microwave absorption medium. Some experimental parameters effecting on extraction efficiency was investigated and optimized. 1.0 g of sample, 8 mL of hexane and three absorbing microwave μ-SPE devices were added in the microwave extraction vessel, the extraction was carried out under 400 W irradiation power at 60 °C for 10 min. The extracts obtained by MAE-μ-SPE were directly analyzed by GC–MS without any clean-up process. The recoveries were in the range of 93.5–104.6%, and the relative standard deviations were lower than 8.7%.

  1. Preparation, characterization of Fe3O4 at TiO2 magnetic nanoparticles and their application for immunoassay of biomarker of exposure to organophosphorus pesticides

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xiao; Wang, Hongbo; Yang, Chunming; Du, Dan; Lin, Yuehe

    2013-03-15

    Novel Fe3O4 at TiO2 magnetic nanoparticles were prepared and developed for a new nanoparticle-based immunosensor for electrochemical quantification of organophosphorylated butyrylcholinesterase (BChE) in plasma, a specific biomarker of exposure to organophosphorus (OP) agents. The Fe3O4 at TiO2 nanoparticles were synthesized by hydrolysis of tetrabutyltitanate on the surface of Fe3O4 magnetic nanospheres, and characterized by attenuated total reflection Fourier-transform infrared spectra, transmission electron microscope and X-ray diffraction. The functional Fe3O4 at TiO2 nanoparticles were performed as capture antibody to selectively enrich phosphorylated moiety instead of phosphoserine antibody in the traditional sandwich immunoassays. The secondary recognition was served by quantum dots (QDs)-tagged anti-BChE antibody (QDs-anti-BChE). With the help of a magnet, the resulting sandwich-like complex, Fe3O4 at TiO2/OP-BChE/QDs-anti-BChE, was easily isolated from sample solutions and the released cadmium ions were detected on a disposable screen-printed electrode (SPE). The binding affinities were investigated by both surface plasmon resonance (SPR) and square wave voltammetry (SWV). This method not only avoids the drawback of unavailability of commercial OP-specific antibody but also amplifies detection signal by QDs-tags together with easy separation of samples by magnetic forces. The proposed immunosensor yields a linear response over a broad OP-BChE concentrations range from 0.02 to 10 nM, with detection limit of 0.01 nM. Moreover, the disposable nanoparticle-based immunosensor has been validated with human plasma samples. It offers a new method for rapid, sensitive, selective and inexpensive screening/evaluating exposure to OP pesticides.

  2. Synthesis and Characterization of TiO2 Modified with Polystyrene and Poly(3-chloro-2-hydroxypropyl Methacrylate as Adsorbents for the Solid Phase Extraction of Organophosphorus Pesticides

    Directory of Open Access Journals (Sweden)

    Enrique Alejo-Molina

    2016-01-01

    Full Text Available Novel hybrid TiO2 particles were developed and assessed as an adsorbent for solid phase extraction (SPE of organophosphorus pesticides (fensulfothion, parathion methyl, coumaphos, and diazinon from spiked water. The sol-gel method was used to synthesize TiO2 particles, which were coated with free-radical polystyrene (PS and poly(3-chloro-2-hydroxypropyl methacrylate (PClHPMA polymers. Particle structures were determined via Fourier transform infrared spectroscopy to confirm that the polymers were successfully anchored to the TiO2 particles. Thermogravimetric analysis was conducted to determine organic and inorganic matter in TiO2-PS and TiO2-PClHPMA particles showing results of 20 : 80 wt/wt% and 23 : 77 wt/wt%, respectively. SEM-EDS and X-ray diffraction test were conducted to determine the morphology and semielemental composition of the particles showing amorphous characteristics. By observing the contact angle, particles coated with PClHPMA were determined to be more hydrophilic than TiO2-PS particles. The pore size distributions obtained from the N2 adsorption-desorption isotherms were 0.150 and 0.168 cm3g−1. The specific surface area (BET was 239.9 m2g−1 for TiO2-PS and 225.7 m2g−1 for TiO2-PClHPMA. The synthesized particles showed relatively high yields of adsorption in SPE. The pesticide recoveries obtained by high performance liquid chromatography ranged from 6 to 26% for TiO2-PClHPMA and 44 to 92% for TiO2-PS.

  3. Pilot-scale incineration of wastes with high content of chlorinated and non-halogenated organophosphorus flame retardants used as alternatives for PBDEs.

    Science.gov (United States)

    Matsukami, Hidenori; Kose, Tomohiro; Watanabe, Mafumi; Takigami, Hidetaka

    2014-09-15

    Chlorinated and non-halogenated organophosphorus flame retardants (OPFRs) including tris(2-chloroisopropyl) phosphate (TCIPP), diethylene glycol bis(di(2-chloroisopropyl) phosphate) (DEG-BDCIPP), triphenyl phosphate (TPHP), and bisphenol A bis(diphenyl phosphate) (BPA-BDPP) have been used increasingly as alternatives to polybrominated diphenyl ethers and other brominated flame retardants. For this study, five batches of incineration experiments of wastes containing approximately 1% of TCIPP, DEG-BDCIPP, TPHP, and BPA-BDPP were conducted using a pilot-scale incinerator. Destruction and emission behaviors of OPFRs were investigated along with the effects on behaviors of unintentional persistent organic pollutants (POPs) such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (dl-PCBs), hexachlorobenzene (HCB), pentachlorobenzene (PeCB), and pentachlorophenol (PCP). Incineration conditions were chosen according to current regulations for waste incinerators in Japan and UNEP. The OPFRs in the input materials were mainly destroyed in the primary combustion with destruction efficiencies greater than 99.999%. Concentrations of the OPFRs in the exhaust gases and ash were, respectively, incineration. Inputs of chlorinated OPFRs did not affect the formation markedly. Destruction and emission behaviors of unintentional POPs were investigated. Emissions of such POPs in exhaust gases and the ash were lower than the Japanese and international standards. Results show that even in wastes with high contents of chlorinated and non-halogenated OPFRs, waste incineration by the current regulations for the waste incinerators can control environmental emissions of OPFRs and unintentional POPs. Incineration is regarded as a best available technology (BAT) for waste management systems. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Determination of organophosphorus flame retardants in fish by pressurized liquid extraction using aqueous solutions and solid-phase microextraction coupled with gas chromatography-flame photometric detector.

    Science.gov (United States)

    Gao, Zhanqi; Deng, Yuehua; Yuan, Wenting; He, Huan; Yang, Shaogui; Sun, Cheng

    2014-10-31

    A novel method was developed for the determination of organophosphorus flame retardants (PFRs) in fish. The method consists of a combination of pressurized liquid extraction (PLE) using aqueous solutions and solid-phase microextraction (SPME), followed by gas chromatography-flame photometric detector (GC-FPD). The experimental parameters that influenced extraction efficiency were systematically evaluated. The optimal responses were observed by extracting 1g of fish meat with the solution of water:acetonitrile (90:10, v/v) at 150°C for 5min and acid-washed silica gel used as lipid sorbent. The obtained extract was then analyzed by SPME coupled with GC-FPD without any additional clean-up steps. Under the optimal conditions, the proposed procedure showed a wide linear range (0.90-5000ngg(-1)) obtained by analyzing the spiked fish samples with increasing concentrations of PFRs and correlation coefficient (R) ranged from 0.9900 to 0.9992. The detection limits (S/N=3) were in the range of 0.010-0.208ngg(-1) with standard deviations (RSDs) ranging from 2.0% to 9.0%. The intra-day and inter-day variations were less than 9.0% and 7.8%, respectively. The proposed method was successfully applied to the determination of PFRs in real fish samples with recoveries varying from 79.8% to 107.3%. The results demonstrate that the proposed method is highly effective for analyzing PFRs in fish samples. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Rapid gas chromatography with flame photometric detection of multiple organophosphorus pesticides in Salvia miltiorrhizae after ultrasonication assisted one-step extraction.

    Science.gov (United States)

    Zhang, Shanshan; Liu, Xiaofei; Qin, Jia'an; Yang, Meihua; Zhao, Hongzheng; Wang, Yong; Guo, Weiying; Ma, Zhijie; Kong, Weijun

    2017-11-15

    A simple and rapid gas chromatography-flame photometric detection (GC-FPD) method was developed for the determination of 12 organophosphorus pesticides (OPPs) in Salvia miltiorrhizae by using ultrasonication assisted one-step extraction (USAE) without any clean-up steps. Some crucial parameters such as type of extraction solvent were optimized to improve the method performance for trace analysis. Any clean-up steps were negligent as no interferences were detected in the GC-FPD chromatograms for sensitive detection. Under the optimized conditions, limits of detection (LODs) and quantitation (LOQs) for all pesticides were in the range of 0.001-0.002mg/kg and 0.002-0.01mg/kg and 0.002-0.01mg/kg, respectively, which were all below the regulatory maximum residue limits suggested. RSDs for method precision (intra- and inter-day variations) were lower than 6.8% in approval with international regulations. Average recovery rates for all pesticides at three fortification levels (0.5, 1.0 and 5.0mg/kg) were in the range of 71.2-101.0% with relative standard deviations (RSDs) pesticide (dimethoate) out of the 12 targets was simultaneously detected in four samples at concentrations of 0.016-0.02mg/kg. Dichlorvos and omethoate were found in the same sample from Sichuan province at 0.004 and 0.027mg/kg, respectively. Malathion and monocrotophos were determined in the other two samples at 0.014 and 0.028mg/kg, respectively. All the positive samples were confirmed by LC-MS/MS. The simple, reliable and rapid USAE-GC-FPD method with many advantages over traditional techniques would be preferred for trace analysis of multiple pesticides in more complex matrices. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Organophosphorus and Carbamate Pesticide Residues Detected in Water Samples Collected from Paddy and Vegetable Fields of the Savar and Dhamrai Upazilas in Bangladesh

    Directory of Open Access Journals (Sweden)

    Nurul Karim

    2012-09-01

    Full Text Available Several types of organophosphorous and carbamate pesticides have been used extensively by the farmers in Bangladesh during the last few decades. Twenty seven water samples collected from both paddy and vegetable fields in the Savar and Dhamrai Upazilas in Bangladesh were analyzed to determine the occurrence and distribution of organo-phosphorus (chlorpyrifos, malathion and diazinon and carbamate (carbaryl and carbofuran pesticide residues. A high performance liquid chromatograph instrument equipped with a photodiode array detector was used to determine the concentrations of these pesticide residues. Diazinon and carbofuran were detected in water samples collected from Savar Upazila at 0.9 μg/L and 198.7 μg/L, respectively. Malathion was also detected in a single water sample at 105.2 μg/L from Dhamrai Upazila. Carbaryl was the most common pesticide detected in Dhamrai Upazila at 14.1 and 18.1 μg/L, while another water sample from Dhamrai Upazila was contaminated with carbofuran at 105.2 μg/L. Chlorpyrifos was not detected in any sample. Overall, the pesticide residues detected were well above the maximum acceptable levels of total and individual pesticide contamination, at 0.5 and 0.1 μg/L, respectively, in water samples recommended by the European Economic Community (Directive 98/83/EC. The presence of these pesticide residues may be attributed by their intense use by the farmers living in these areas. Proper handling of these pesticides should be ensured to avoid direct or indirect exposure to these pesticides.

  7. Is the World Health Organization-recommended dose of pralidoxime effective in the treatment of organophosphorus poisoning? A randomized, double-blinded and placebo-controlled trial

    Directory of Open Access Journals (Sweden)

    Sumaya Syed

    2015-01-01

    Full Text Available Background: Organophosphorus poisoning (OPP is a major global public health problem. Pralidoxime has been used in a complimentary role to atropine for the management of OPP. World Health Organization (WHO recommends use of pralidoxime but studies regarding its role have been inconclusive, ranging from being ineffective to harmful or beneficial. Materials and Methods: The present study was undertaken to evaluate the effectiveness of pralidoxime. Eddleston′s study was the most compelling factor for our study, as he showed worst outcomes using pralidoxime. Our practice of continuous use of pralidoxime was based on the WHO guidelines and the study by Pawar (2006, which showed better outcome with higher doses of pralidoxime. These conflicting results suggested that a re-evaluation of its use in our clinical practice was indicated. Results: There was no difference in mortality rates, hemodynamic parameters and atropine requirements between the AP and A groups. Mean duration of ventilation (3.6 ± 4.6 in AP group vs. 3.6 ± 4.4 in A group and Intensive Care Unit stay (7.1 ± 5.4 in AP group vs. 6.8 ± 4.7 in A group was comparable. Serum sodium concentrations showed a correlation with mortality, with lower concentrations associated with better outcomes. Conclusion: The study suggests that add-on WHO-recommended pralidoxime therapy does not provide any benefit over atropine monotherapy. Adding pralidoxime does not seem to be beneficial and at the same time does not result in increased mortality rates. Our practice changed after completion of this study, and it has proven to be of significant benefit to patients who had to bear the expense of treatment.

  8. An absorbing microwave micro-solid-phase extraction device used in non-polar solvent microwave-assisted extraction for the determination of organophosphorus pesticides

    Energy Technology Data Exchange (ETDEWEB)

    Wang Ziming, E-mail: wangziming@jlu.edu.cn [College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012 (China); College of Environment and Resources, Jilin University, 2699 Qianjin Street, Changchun 130012 (China); Zhao Xin; Xu Xu; Wu Lijie; Su Rui; Zhao Yajing; Jiang Chengfei; Zhang Hanqi [College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012 (China); Ma Qiang [Chinese Academy of Inspection and Quarantine, Beijing 100123 (China); Lu Chunmei [College of Technology Center, Jilin Entry-Exit Inspection and Quarantine Bureau, Changchun 130062 (China); Dong Deming [College of Environment and Resources, Jilin University, 2699 Qianjin Street, Changchun 130012 (China)

    2013-01-14

    Highlights: Black-Right-Pointing-Pointer An absorbing microwave {mu}-SPE device packed with activated carbon was used. Black-Right-Pointing-Pointer Absorbing microwave {mu}-SPE device was made and used to enrich the analytes. Black-Right-Pointing-Pointer Absorbing microwave {mu}-SPE device was made and used to heat samples directly. Black-Right-Pointing-Pointer MAE-{mu}-SPE was applied to the extraction of OPPs with non-polar solvent only. - Abstract: A single-step extraction-cleanup method, including microwave-assisted extraction (MAE) and micro-solid-phase extraction ({mu}-SPE), was developed for the extraction of ten organophosphorus pesticides in vegetable and fruit samples. Without adding any polar solvent, only one kind of non-polar solvent (hexane) was used as extraction solvent in the whole extraction step. Absorbing microwave {mu}-SPE device, was prepared by packing activated carbon with microporous polypropylene membrane envelope, and used as not only the sorbent in {mu}-SPE, but also the microwave absorption medium. Some experimental parameters effecting on extraction efficiency was investigated and optimized. 1.0 g of sample, 8 mL of hexane and three absorbing microwave {mu}-SPE devices were added in the microwave extraction vessel, the extraction was carried out under 400 W irradiation power at 60 Degree-Sign C for 10 min. The extracts obtained by MAE-{mu}-SPE were directly analyzed by GC-MS without any clean-up process. The recoveries were in the range of 93.5-104.6%, and the relative standard deviations were lower than 8.7%.

  9. Comparative Pharmacokinetics of the Organophosphorus Insecticide Chlorpyrifos and its Major Metabolites Diethylphosphate, Diethylthiophosphate and 3,5,6-Trichloro-2-pyridinol in the Rat

    Energy Technology Data Exchange (ETDEWEB)

    Timchalk, Chuck; Busby, Andrea L; Campbell, James A; Needham, Larry L; Barr, Dana

    2007-07-31

    Abstract Chlorpyrifos (CPF) is a commonly used diethylphosphorothionate organophosphorus (OP) insecticide. Diethylphosphate (DEP), diethylthiophosphate (DETP) and 3,5,6-trichloro-2-pyridinol (TCPy) are products of metabolism and of environmental degradation of CPF and are routinely measured in urine as biomarkers of exposure. However, because these same chemicals can result from metabolism or by biodegradation, monitoring total urinary metabolite levels may be reflective of not only an individual’s contact with the parent pesticide, but also exposure with the metabolites, which are present in the environment. The objective of the current study was to compare the pharmacokinetics of orally administered DEP, DETP and TCPy with their kinetics following oral dosing with the parent insecticide CPF in the rat. Groups of rats were orally administered CPF, DEP, TCPy or DETP at doses of 140 μmol/kg body weight, and the time-courses of the metabolites were evaluated in blood and urine. Following oral administration, all three metabolites were well absorbed with peak blood concentrations being attained between 1-3 h post-dosing. In the case of DEP and TCPy virtually all the administered dose was recovered in the urine by 72 h post-dosing, suggesting negligible, if any, metabolism; whereas with DETP, ~50% of the orally administered dose was recovered in the urine. The CPF oral dose was likewise rapidly absorbed and metabolized to DEP, TCPy and DETP, with the distribution of metabolites in the urine followed the order: TCPy (22 ± 3 μmol) > DETP (14 ± 2 μmol) > DEP (1.4 ± 0.7 μmol). Based upon the total amount of TCPy detected in the urine a minimum of 63% of the oral CPF dose was absorbed. These studies support the hypotheses that DEP, DETP and TCPy present in the environment can be readily absorbed and eliminated in the urine of rats and potentially humans.

  10. Enzyme inhibition by iminosugars

    DEFF Research Database (Denmark)

    López, Óscar; Qing, Feng-Ling; Pedersen, Christian Marcus

    2013-01-01

    Imino- and azasugar glycosidase inhibitors display pH dependant inhibition reflecting that both the inhibitor and the enzyme active site have groups that change protonation state with pH. With the enzyme having two acidic groups and the inhibitor one basic group, enzyme-inhibitor complexes...

  11. Quorum sensing inhibition

    DEFF Research Database (Denmark)

    Persson, T.; Givskov, Michael Christian; Nielsen, J.

    2005-01-01

    /receptor transcriptional regulator in some clinically relevant Gram-negative bacteria. The present review contains all reported compound types that are currently known to inhibit the QS transcriptional regulator in Gram-negative bacteria. These compounds are sub-divided into two main groups, one comprising structural...

  12. Cooperation for Better Inhibiting.

    Science.gov (United States)

    Novoa, Eva Maria; Ribas de Pouplana, Lluís

    2015-06-18

    Cladosporin is an antimalarial drug that acts as an ATP-mimetic to selectively inhibit Plasmodium lysyl-tRNA synthetase. Using multiple crystal structures, Fang et al. (2015) reveal in this issue of Chemistry & Biology the fascinating mechanism responsible for cladosporin selectivity. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. A speculated cause of respiratory inhibition in infants.

    Science.gov (United States)

    Minowa, Hideki; Arai, Ikuyo; Yasuhara, Hajime; Ebisu, Reiko; Ohgitani, Ayako

    2018-10-01

    In our previous studies, we documented that threatened premature labor and asymmetrical intrauterine growth restriction were risk factors for respiratory inhibition. The goal of this study was to determine the cause of respiratory inhibition by considering perinatal risk factors. We examined 1497 infants with a gestational age of 36 weeks or greater. All infants were monitored using pulse oximetry and examined via cranial sonography. Respiratory inhibition was defined as severe hypoxemia caused by respiratory inhibition immediately after crying or gastroesophageal reflux or as a respiratory pause during feeding. We examined the relationships between respiratory inhibition and perinatal factors and speculated on the cause of respiratory inhibition. The median gestational age, birth weight, Apgar score at 1 min, and Apgar score at 5 min of the subjects were 38.9 weeks, 2930 g, 8.0 points, and 9.0 points, respectively. Respiratory inhibition was observed in 422 infants. Lateral ventricle enlargement and increased echogenicity in the ganglionic eminence were observed in 417 and 516 infants, respectively. Respiratory inhibition was significantly correlated with shorter gestational periods, twin pregnancies, lateral ventricle enlargement, and increased echogenicity in the ganglionic eminence. We speculate that umbilical cord compression is a major cause of respiratory inhibition.

  14. Analysis of monomeric and oligomeric organophosphorus flame retardants in fish muscle tissues using liquid chromatography–electrospray ionization tandem mass spectrometry: Application to Nile tilapia (Oreochromis niloticus from an e-waste processing area in northern Vietnam

    Directory of Open Access Journals (Sweden)

    Hidenori Matsukami

    2016-06-01

    Full Text Available Using electrospray ionization tandem mass spectrometry combined with liquid chromatography (LC, a novel analytical method was developed to quantify eight monomeric organophosphorus flame retardants (m-PFRs and three oligomeric organophosphorus flame retardants (o-PFRs in fish muscle samples. The optimization and validation experiments indicate that the developed method can determine accurately the concentrations of analytes in fish muscle samples. The recoveries of analytes in fish muscle samples were in the range of 74–105%. The coefficients of variation of the concentrations of analytes in fish muscle samples were 0.6–8.9%. The concentrations of analytes in procedural blanks were below the limit of quantification (LOQ values. Furthermore, the developed method was applied to the analysis of m-PFRs and o-PFRs in the muscle samples of tilapias collected from an electronic waste (e-waste processing area in northern Vietnam. The concentrations of m-PFRs such as tris(2-chloroethyl phosphate (TCEP, tris(2-chloroisopropyl phosphate (TCIPP, and triphenyl phosphate (TPHP were dominant among the investigated m-PFRs. The respective concentrations of TCEP, TCIPP, and TPHP were up to 160, 300, and 230 ng g−1 lipid weight, respectively, whereas those of o-PFRs were up to 10 ng g−1 lipid weight. The results of this study indicate lower accumulation potential of o-PFRs compared with m-PFRs for the first time.

  15. Preliminary characterisation of an in vitro paradigm for the study of the delayed effects of organophosphorus compounds: hen embryo brain spheroids

    International Nuclear Information System (INIS)

    Sales, K.M.; Kingston, S.T.; Doyle, K.M.; Purcell, W.M.

    2004-01-01

    Organophosphate induced delayed neuropathy (OPIDN) has been studied extensively but the mechanisms of toxicity remain unclear. It is generally accepted that the inhibition and ageing (dealkylation) of the B-esterase neuropathy target esterase (NTE) is integral to axonal loss. At present, the only way of detecting compounds that induce OPIDN is the hen test, an animal model. In this study, we preliminary validated hen embryo brain spheroids (HEBS) for the study of organophosphate (OP) toxicity. Hen brain spheroids have been characterised previously, although they have never been fully optimised for OP testing. We optimised the levels of acetylcholine esterase (AChE) and neuropathy target esterase by adapting the culture technique and using chemically defined media. Spheroid cultures were maintained for 35 days and viability and enzyme levels were monitored over this time. Levels of AChE and NTE in this system remained stable over the 35 day period. Using transmission electron microscopy, we have shown synaptogenisis within HEBS earlier than previously suggested in spheroid culture. These studies indicate that HEBS may be useful for the study of OP-induced toxicity and that the long-term stability of the cultures makes it an ideal candidate for studying OPIDN

  16. Plastics for corrosion inhibition

    CERN Document Server

    Goldade, Victor A; Makarevich, Anna V; Kestelman, Vladimir N

    2005-01-01

    The development of polymer composites containing inhibitors of metal corrosion is an important endeavour in modern materials science and technology. Corrosion inhibitors can be located in a polymer matrix in the solid, liquid or gaseous phase. This book details the thermodynamic principles for selecting these components, their compatibility and their effectiveness. The various mechanisms of metal protection – barrier, inhibiting and electromechanical – are considered, as are the conflicting requirements placed on the structure of the combined material. Two main classes of inhibited materials (structural and films/coatings) are described in detail. Examples are given of structural plastics used in friction units subjected to mechano-chemical wear and of polymer films/coatings for protecting metal objects against corrosion.

  17. Inhibiting the inevitable

    DEFF Research Database (Denmark)

    Shashoua, Yvonne

    2006-01-01

    conservation is to ‘buy time’ for the object. Inhibitive conservation of plastics involves the removal or reduction of factors causing or accelerating degradation including light, oxygen, acids, relative humidity and acidic breakdown products. Specific approaches to conservation have been developed......Once plastics objects are registered in museum collections, the institution becomes responsible for their long term preservation, until the end of their useful lifetime. Plastics appear to deteriorate faster than other materials in museum collections and have a useful lifetime between 5 and 25...... years. Preventive or inhibitive conservation involves controlling the environments in which objects are placed during storage and display, with the aim of slowing the major deterioration reactions. Once in progress, degradation of plastics cannot be stopped or reversed, so the aim of preventive...

  18. Flame retardant emission from e-waste recycling operation in northern Vietnam: Environmental occurrence of emerging organophosphorus esters used as alternatives for PBDEs

    International Nuclear Information System (INIS)

    Matsukami, Hidenori; Tue, Nguyen Minh; Suzuki, Go; Someya, Masayuki; Tuyen, Le Huu; Viet, Pham Hung; Takahashi, Shin; Tanabe, Shinsuke; Takigami, Hidetaka

    2015-01-01

    Three oligomeric organophosphorus flame retardants (o-PFRs), eight monomeric PFRs (m-PFRs), tetrabromobisphenol A (TBBPA), and polybrominated diphenyl ethers (PBDEs) were identified and quantified in surface soils and river sediments around the e-waste recycling area in Bui Dau, northern Vietnam. Around the e-waste recycling workshops, 1,3-phenylene bis(diphenyl phosphate) (PBDPP), bisphenol A bis(diphenyl phosphate) (BPA-BDPP), triphenyl phosphate (TPHP), TBBPA, and PBDEs were dominant among the investigated flame retardants (FRs). The respective concentrations of PBDPP, BPA-BDPP, TPHP, TBBPA and the total PBDEs were 6.6–14000 ng/g-dry, < 2–1500 ng/g-dry, 11–3300 ng/g-dry, < 5–2900 ng/g-dry, and 67–9200 ng/g-dry in surface soils, and 4.4–78 ng/g-dry, < 2–20 ng/g-dry, 7.3–38 ng/g-dry, 6.0–44 ng/g-dry and 100–350 ng/g-dry in river sediments. Near the open burning site of e-waste, tris(methylphenyl) phosphate (TMPP), (2-ethylhexyl)diphenyl phosphate (EHDPP), TPHP, and the total PBDEs were abundantly with respective concentrations of < 2–190 ng/g-dry, < 2–69 ng/g-dry, < 3–51 ng/g-dry and 1.7–67 ng/g-dry in surface soils. Open storage and burning of e-waste have been determined to be important factors contributing to the emissions of FRs. The environmental occurrence of emerging FRs, especially o-PFRs, indicates that the alternation of FRs addition in electronic products is shifting in response to domestic and international regulations of PBDEs. The emissions of alternatives from open storage and burning of e-waste might become greater than those of PBDEs in the following years. The presence and environmental effects of alternatives should be regarded as a risk factor along with e-waste recycling. - Highlights: • Open storage and burning of e-waste contributed to emission of FRs. • Types of FRs currently in emission are shifting in response to regulations of PBDEs. • Emerging PFRs were detected in soils and sediments around e

  19. Flame retardant emission from e-waste recycling operation in northern Vietnam: Environmental occurrence of emerging organophosphorus esters used as alternatives for PBDEs

    Energy Technology Data Exchange (ETDEWEB)

    Matsukami, Hidenori, E-mail: matsukami.hidenori@nies.go.jp [Center for Material Cycles and Waste Management Research, National Institute for Environmental Studies (NIES), 16-2 Onogawa, Tsukuba 305-8506 (Japan); Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa 277-8563 (Japan); Tue, Nguyen Minh [Center for Marine Environmental Studies (CMES), Ehime University, 2-5 Bunkyo-cho, Matsuyama 790-8577 (Japan); Centre for Environmental Technology and Sustainable Development (CETASD), Hanoi University of Science, 334 Nguyen Trai, Hanoi (Viet Nam); Suzuki, Go [Center for Material Cycles and Waste Management Research, National Institute for Environmental Studies (NIES), 16-2 Onogawa, Tsukuba 305-8506 (Japan); Someya, Masayuki [Tokyo Metropolitan Research Institute for Environmental Protection, 1-7-5 Shinsuna Koto, Tokyo 136-0075 (Japan); Tuyen, Le Huu; Viet, Pham Hung [Centre for Environmental Technology and Sustainable Development (CETASD), Hanoi University of Science, 334 Nguyen Trai, Hanoi (Viet Nam); Takahashi, Shin [Center for Marine Environmental Studies (CMES), Ehime University, 2-5 Bunkyo-cho, Matsuyama 790-8577 (Japan); Center of Advanced Technology for the Environment, Faculty of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama 790-8566 (Japan); Tanabe, Shinsuke [Center for Marine Environmental Studies (CMES), Ehime University, 2-5 Bunkyo-cho, Matsuyama 790-8577 (Japan); Takigami, Hidetaka [Center for Material Cycles and Waste Management Research, National Institute for Environmental Studies (NIES), 16-2 Onogawa, Tsukuba 305-8506 (Japan); Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa 277-8563 (Japan)

    2015-05-01

    Three oligomeric organophosphorus flame retardants (o-PFRs), eight monomeric PFRs (m-PFRs), tetrabromobisphenol A (TBBPA), and polybrominated diphenyl ethers (PBDEs) were identified and quantified in surface soils and river sediments around the e-waste recycling area in Bui Dau, northern Vietnam. Around the e-waste recycling workshops, 1,3-phenylene bis(diphenyl phosphate) (PBDPP), bisphenol A bis(diphenyl phosphate) (BPA-BDPP), triphenyl phosphate (TPHP), TBBPA, and PBDEs were dominant among the investigated flame retardants (FRs). The respective concentrations of PBDPP, BPA-BDPP, TPHP, TBBPA and the total PBDEs were 6.6–14000 ng/g-dry, < 2–1500 ng/g-dry, 11–3300 ng/g-dry, < 5–2900 ng/g-dry, and 67–9200 ng/g-dry in surface soils, and 4.4–78 ng/g-dry, < 2–20 ng/g-dry, 7.3–38 ng/g-dry, 6.0–44 ng/g-dry and 100–350 ng/g-dry in river sediments. Near the open burning site of e-waste, tris(methylphenyl) phosphate (TMPP), (2-ethylhexyl)diphenyl phosphate (EHDPP), TPHP, and the total PBDEs were abundantly with respective concentrations of < 2–190 ng/g-dry, < 2–69 ng/g-dry, < 3–51 ng/g-dry and 1.7–67 ng/g-dry in surface soils. Open storage and burning of e-waste have been determined to be important factors contributing to the emissions of FRs. The environmental occurrence of emerging FRs, especially o-PFRs, indicates that the alternation of FRs addition in electronic products is shifting in response to domestic and international regulations of PBDEs. The emissions of alternatives from open storage and burning of e-waste might become greater than those of PBDEs in the following years. The presence and environmental effects of alternatives should be regarded as a risk factor along with e-waste recycling. - Highlights: • Open storage and burning of e-waste contributed to emission of FRs. • Types of FRs currently in emission are shifting in response to regulations of PBDEs. • Emerging PFRs were detected in soils and sediments around e

  20. Developmental Changes in Visual and Auditory Inhibition in Early Childhood

    Science.gov (United States)

    Guy, Jacalyn; Rogers, Maria; Cornish, Kim

    2012-01-01

    The development of executive functions in the preschool years is not fully understood. Although there exists a large body of research investigating the maturation of executive functioning in school-aged children, little is known about the emergence of such skills, in particular inhibition, among preschool-aged children. Understanding developmental…

  1. Ageing Polulations

    DEFF Research Database (Denmark)

    Christiansen, Terkel; Lauridsen, Jørgen Trankjær; Bech, Mickael

    2013-01-01

    An ageing society is characterised by an increasing median age of the population. The purpose of this chapter is to document the existing knowledge about the association between population ageing and health care expenditure, and to supplement this overview by a summary of our original research...... is that ageing as such can be expected only to a cause modest increase in health care expenditure per capita in the future. This conclusion is supported by our own empirical study, based on 15 EU countries....

  2. Skin Aging

    Science.gov (United States)

    Your skin changes as you age. You might notice wrinkles, age spots and dryness. Your skin also becomes thinner and loses fat, making it ... heal, too. Sunlight is a major cause of skin aging. You can protect yourself by staying out ...

  3. Communication & Aging.

    Science.gov (United States)

    Arnold, William E.

    This extensive bibliography contains more than 1,800 entries about communication and aging. The citations include journal articles, unpublished papers, speeches, dissertations, research studies, and books that relate aging and the aged to a variety of topics, including the following: physiological deterioration, socialization, political…

  4. Development of a Physiologically Based Pharmacokinetic and Pharmacodynamic Model to Determine Dosimetry and Cholinesterase Inhibition for a Binary Mixture of Chlorpyrifos and Diazinon in the Rat

    Energy Technology Data Exchange (ETDEWEB)

    Timchalk, Chuck; Poet, Torka S.

    2008-05-01

    Physiologically based pharmacokinetic/pharmacodynamic (PBPK/PD) models have been developed and validated for the organophosphorus (OP) insecticides chlorpyrifos (CPF) and diazinon (DZN). Based on similar pharmacokinetic and mode of action properties it is anticipated that these OPs could interact at a number of important metabolic steps including: CYP450 mediated activation/detoxification, and blood/tissue cholinesterase (ChE) binding/inhibition. We developed a binary PBPK/PD model for CPF, DZN and their metabolites based on previously published models for the individual insecticides. The metabolic interactions (CYP450) between CPF and DZN were evaluated in vitro and suggests that CPF is more substantially metabolized to its oxon metabolite than is DZN. These data are consistent with their observed in vivo relative potency (CPF>DZN). Each insecticide inhibited the other’s in vitro metabolism in a concentration-dependent manner. The PBPK model code used to described the metabolism of CPF and DZN was modified to reflect the type of inhibition kinetics (i.e. competitive vs. non-competitive). The binary model was then evaluated against previously published rodent dosimetry and ChE inhibition data for the mixture. The PBPK/PD model simulations of the acute oral exposure to single- (15 mg/kg) vs. binary-mixtures (15+15 mg/kg) of CFP and DZN at this lower dose resulted in no differences in the predicted pharmacokinetics of either the parent OPs or their respective metabolites; whereas, a binary oral dose of CPF+DZN at 60+60 mg/kg did result in observable changes in the DZN pharmacokinetics. Cmax was more reasonably fit by modifying the absorption parameters. It is anticipated that at low environmentally relevant binary doses, most likely to be encountered in occupational or environmental related exposures, that the pharmacokinetics are expected to be linear, and ChE inhibition dose-additive.

  5. Advanced Glycation End Products Inhibit the Proliferation of Human Umbilical Vein Endothelial Cells by Inhibiting Cathepsin D

    Directory of Open Access Journals (Sweden)

    Yuan Li

    2017-02-01

    Full Text Available We aimed to investigate the effect of advanced glycation end products (AGEs on the proliferation and migration ability of human umbilical vein endothelial cells (HUVECs. Cell proliferation was detected by methyl thiazolyl tetrazolium (MTT assay, real-time cell analyzer and 5-Ethynyl-2′-deoxyuridine (EdU staining. Cell migration was detected by wound-healing and transwell assay. AGEs significantly inhibited the proliferation and migration of HUVECs in a time-and dose-dependent way. Western blotting revealed that AGEs dramatically increased the expression of microtubule-associated protein 1 light chain 3 (LC3 II/I and p62. Immunofluorescence of p62 and acridine orange staining revealed that AGEs significantly increased the expression of p62 and the accumulation of autophagic vacuoles, respectively. Chloroquine (CQ could further promote the expression of LC3 II/I and p62, increase the accumulation of autophagic vacuoles and promote cell injury induced by AGEs. In addition, AGEs reduced cathepsin D (CTSD expression in a time-dependent way. Overexpression of wild-type CTSD significantly decreased the ratio of LC 3 II/I as well as p62 accumulation induced by AGEs, but overexpression of catalytically inactive mutant CTSD had no such effects. Only overexpression of wild-type CTSD could restore the proliferation of HUVECs inhibited by AGEs. However, overexpression of both wild-type CTSD and catalytically inactive mutant CTSD could promote the migration of HUVECs inhibited by AGEs. Collectively, our study found that AGEs inhibited the proliferation and migration in HUVECs and promoted autophagic flux, which in turn played a protective role against AGEs-induced cell injury. CTSD, in need of its catalytic activity, may promote proliferation in AGEs-treated HUVECs independent of the autophagy-lysosome pathway. Meanwhile, CTSD could improve the migration of AGEs-treated HUVECs regardless of its enzymatic activity.

  6. Advanced Glycation End Products Inhibit the Proliferation of Human Umbilical Vein Endothelial Cells by Inhibiting Cathepsin D.

    Science.gov (United States)

    Li, Yuan; Chang, Ye; Ye, Ning; Dai, Dongxue; Chen, Yintao; Zhang, Naijin; Sun, Guozhe; Sun, Yingxian

    2017-02-17

    We aimed to investigate the effect of advanced glycation end products (AGEs) on the proliferation and migration ability of human umbilical vein endothelial cells (HUVECs). Cell proliferation was detected by methyl thiazolyl tetrazolium (MTT) assay, real-time cell analyzer and 5-Ethynyl-2'-deoxyuridine (EdU) staining. Cell migration was detected by wound-healing and transwell assay. AGEs significantly inhibited the proliferation and migration of HUVECs in a time-and dose-dependent way. Western blotting revealed that AGEs dramatically increased the expression of microtubule-associated protein 1 light chain 3 (LC3) II/I and p62. Immunofluorescence of p62 and acridine orange staining revealed that AGEs significantly increased the expression of p62 and the accumulation of autophagic vacuoles, respectively. Chloroquine (CQ) could further promote the expression of LC3 II/I and p62, increase the accumulation of autophagic vacuoles and promote cell injury induced by AGEs. In addition, AGEs reduced cathepsin D (CTSD) expression in a time-dependent way. Overexpression of wild-type CTSD significantly decreased the ratio of LC 3 II/I as well as p62 accumulation induced by AGEs, but overexpression of catalytically inactive mutant CTSD had no such effects. Only overexpression of wild-type CTSD could restore the proliferation of HUVECs inhibited by AGEs. However, overexpression of both wild-type CTSD and catalytically inactive mutant CTSD could promote the migration of HUVECs inhibited by AGEs. Collectively, our study found that AGEs inhibited the proliferation and migration in HUVECs and promoted autophagic flux, which in turn played a protective role against AGEs-induced cell injury. CTSD, in need of its catalytic activity, may promote proliferation in AGEs-treated HUVECs independent of the autophagy-lysosome pathway. Meanwhile, CTSD could improve the migration of AGEs-treated HUVECs regardless of its enzymatic activity.

  7. Active ageing

    Directory of Open Access Journals (Sweden)

    Frode F. Jacobsen

    2017-09-01

    Full Text Available Background: The concept of active ageing has been gaining prominence in the Nordic countries and beyond. This has been reflected in policy papers in Norway and other Nordic nations. Aims: The aim of this article is to analyse the topic of active ageing in five Norwegian White Papers (2002 to 2015 and discuss those policy documents in context of relevant research literature. Methods: A qualitative document analyses is employed focusing on how active ageing, and ageing in general, is described and which concepts are employed. No ethical approval was needed. Findings: The general theme of ageing and the specific theme of active ageing are increasingly prominent in the Norwegian White Papers studied. In all documents, some assumptions regarding ageing and active ageing seem implicit, such as independence being more important than (interdependence. ‘Productive’ activities like participation in working life are stressed, while others, like reading, watching TV or watching children playing in the street, are ignored. Conclusions: The policy documents demonstrate that the topic of active ageing is growing in importance. The documents increasingly seem to stress ‘productive’ activities – those related to working life, voluntary work or sports and physical training. They exclude activities that are meaningful for many older people, like watching their grandchildren play or reading books. Implications for practice: Practitioners in older people’s care could consider reflecting on: Government documents dealing with their own practice The prevalent concept of active ageing The trend of active ageing as a facilitating or hindering factor for good care work How present discourse on active ageing may influence their attitude towards frail older persons How they wish to relate to active ageing in their own practice

  8. Influence of the nature of the components of extraction systems used for the extraction of radionuclides on the interfacial tension. II. Influence of the structure of neutral organophosphorus reagents

    International Nuclear Information System (INIS)

    Shmidt, V.S.; Nikitin, S.D.

    1984-01-01

    Isotherms of the interfacial tension were obtained on the interfaces between water or 3 M HNO 3 and solutions of various neutral organophosphorus compounds (NOPC). The values of the work of adsorption W and the standard free energy of adsorption Δμ/sup theta/ of these compounds on the interface from the organic phase were calculated. It was shown that linear dependence of W and Δμ/sup theta/ on the sum of the Kabachnik parameters sigmaΣ/sub Phi/ of the substituents at the phosphorus atom in the molecules of these extraction reagents are observed; this is an indication of the possibility of using the principle of linear free energy ratios (LFE) for predicting the interfacial activity of NOPC of various structures

  9. The development of children's inhibition: does parenting matter?

    Science.gov (United States)

    Roskam, Isabelle; Stievenart, Marie; Meunier, Jean-Christophe; Noël, Marie-Pascale

    2014-06-01

    Whereas a large body of research has investigated the maturation of inhibition in relation to the prefrontal cortex, far less research has been devoted to environmental factors that could contribute to inhibition improvement. The aim of the current study was to test whether and to what extent parenting matters for inhibition development from 2 to 8years of age. Data were collected from 421 families, with 348 mother-child dyads and 342 father-child dyads participating. Children's inhibition capacities and parenting behaviors were assessed in a three-wave longitudinal data collection. The main analyses examined the impact of parenting on the development of children's inhibition capacities. They were conducted using a multilevel modeling (MLM) framework. The results lead to the conclusion that both mothers and fathers contribute through their child-rearing behavior to their children's executive functioning, even when controlling for age-related improvement (maturation) and important covariates such as gender, verbal IQ, and place of enrollment. More significant relations between children's inhibition development and parenting were displayed for mothers than for fathers. More precisely, parenting behaviors that involve higher monitoring, lower discipline, inconsistency and negative controlling, and a positive parenting style are associated with good development of inhibition capacities in children. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Aging research

    International Nuclear Information System (INIS)

    Ross, D.F. Jr.

    1988-01-01

    The USNRC Office of Nuclear Regulatory Research has developed a program for nuclear plant aging research (NPAR) to achieve an understanding of nuclear plant aging, its potential effects on safety, and methods for its detection and mitigation, sufficient for addressing safety and regulatory issues and supporting regulatory decisions on issues. Specifically, the NRC has aggressive research and regulatory programs associated with aging effects on piping, steam generators, containments, structures, and electrical and mechanical systems and components. In addition to safety assessment for the original license period for nuclear power plants, this aging information will be extremely useful in providing technical bases for efficient and effective regulation associated with possible license extension. This paper discusses the major activities of USNRC sponsored aging research program and recommends an approach to manage and handle aging at nuclear power plants

  11. Anxiety and retrieval inhibition: support for an enhanced inhibition account.

    Science.gov (United States)

    Nuñez, Mia; Gregory, Josh; Zinbarg, Richard E

    2017-02-01

    Retrieval inhibition of negative associations is important for exposure therapy for anxiety, but the relationship between memory inhibition and anxiety is not well understood-anxiety could either be associated with enhanced or deficient inhibition. The present study tested these two competing hypotheses by measuring retrieval inhibition of negative stimuli by related neutral stimuli. Non-clinically anxious undergraduates completed measures of trait and state anxiety and completed a retrieval induced forgetting task. Adaptive forgetting varied with state anxiety. Low levels of state anxiety were associated with no evidence for retrieval inhibition for either threatening or non-threatening categories. Participants in the middle tertile of state anxiety scores exhibited retrieval inhibition for non-threatening categories but not for threatening categories. Participants in the highest tertile of state anxiety, however, exhibited retrieval inhibition for both threatening and non-threatening categories with the magnitude of retrieval inhibition being greater for threatening than non-threatening categories. The data are in line with the avoidance aspect of the vigilance-avoidance theory of anxiety and inhibition. Implications for cognitive behavioural therapy practices are discussed.

  12. Inhibition of polyphenoloxidase by sulfite

    International Nuclear Information System (INIS)

    Sayavedra-Soto, L.A.; Montgomery, M.W.

    1986-01-01

    When polyphenoloxidase (PPO) was exposed to sulfite prior to substrate addition, inhibition was irreversible. Trials to regenerate PPO activity, using extensive dialysis, column chromatography, and addition of copper salts were not successful. Increased concentrations of sulfite and pH levels less than 5 enhanced the inhibition of PPO by sulfite. At pH 4, concentrations greater than 0.04 mg/mL completely inhibited 1000 units of PPO activity almost instantaneously. This suggested that the HSO 3 - molecule was the main component in the sulfite system inhibiting PPO. Column chromatography, extensive dialysis, and gel electrophoresis did not demonstrate 35 SO 2 bound to purified pear PPO protein. Formation of extra protein bands of sulfite inhibited purified pear PPO fractions on gel electrophoresis was demonstrated. This and other evidence suggested that the major mode of direct irreversible inhibition of PPO was modification of the protein structure, with retention of its molecular unity

  13. Successful ageing

    DEFF Research Database (Denmark)

    Kusumastuti, Sasmita; Derks, Marloes G. M.; Tellier, Siri

    2016-01-01

    BACKGROUND: Ageing is accompanied by an increased risk of disease and a loss of functioning on several bodily and mental domains and some argue that maintaining health and functioning is essential for a successful old age. Paradoxically, studies have shown that overall wellbeing follows a curvili...

  14. Ageing genes

    DEFF Research Database (Denmark)

    Rattan, Suresh

    2018-01-01

    The idea of gerontogenes is in line with the evolutionary explanation of ageing as being an emergent phenomenon as a result of the imperfect maintenance and repair systems. Although evolutionary processes did not select for any specific ageing genes that restrict and determine the lifespan...... of an individual, the term ‘gerontogenes’ primarily refers to any genes that may seem to influence ageing and longevity, without being specifically selected for that role. Such genes can also be called ‘virtual gerontogenes’ by virtue of their indirect influence on the rate and process of ageing. More than 1000...... virtual gerontogenes have been associated with ageing and longevity in model organisms and humans. The ‘real’ genes, which do influence the essential lifespan of a species, and have been selected for in accordance with the evolutionary life history of the species, are known as the longevity assurance...

  15. Successful Aging

    Directory of Open Access Journals (Sweden)

    Taufiqurrahman Nasihun

    2015-06-01

    Full Text Available The emerging concept of successful aging is based on evidence that in healthy individual when they get aged, there are  considerable variations in physiological functions alteration. Some people exhibiting greater, but others very few or no age related alteration. The first is called poor aging and the later is called successful pattern of aging (Lambert SW, 2008. Thus, in the simple words the successful aging concept is define as an opportunity of old people to stay  active and productive condition despite they get aged chronologically. Aging itself might be defined as the progressive accumulation of changes with time associated with or responsible for the ever-increasing susceptibility to disease and death which accompanies advancing age (Harman D, 1981. The time needed to accumulate changes is attributable to aging process. The marked emerging questions are how does aging happen and where does aging start? To answer these questions and because of the complexity of aging process, there are more than 300 aging theories have been proposed to explain how and where aging occured and started respectively. There are too many to enumerate theories and classification of aging process. In summary, all of these aging theories can be grouped into three clusters: 1. Genetics program theory, this theory suggests that aging is resulted from program directed by the genes; 2. Epigenetic theory, in these theory aging is resulted from environmental random events not determined by the genes; 3. Evolutionary theory, which propose that aging is a medium for disposal mortal soma in order to avoid competition between organism and their progeny for food and space, did not try to explain how aging occur, but possibly answer why aging occur (De la Fuente. 2009. Among the three groups of aging theories, the epigenetic theory is useful to explain and try to solve the enigma of aging which is prominently caused by internal and external environmental influences

  16. Probing the reactivation process of sarin-inhibited acetylcholinesterase with α-nucleophiles: hydroxylamine anion is predicted to be a better antidote with DFT calculations.

    Science.gov (United States)

    Khan, Md Abdul Shafeeuulla; Lo, Rabindranath; Bandyopadhyay, Tusar; Ganguly, Bishwajit

    2011-08-01

    Inactivation of acetylcholinesterase (AChE) due to inhibition by organophosphorus (OP) compounds is a major threat to human since AChE is a key enzyme in neurotransmission process. Oximes are used as potential reactivators of OP-inhibited AChE due to their α-effect nucleophilic reactivity. In search of more effective reactivating agents, model studies have shown that α-effect is not so important for dephosphylation reactions. We report the importance of α-effect of nucleophilic reactivity towards the reactivation of OP-inhibited AChE with hydroxylamine anion. We have demonstrated with DFT [B3LYP/6-311G(d,p)] calculations that the reactivation process of sarin-serine adduct 2 with hydroxylamine anion is more efficient than the other nucleophiles reported. The superiority of hydroxylamine anion to reactivate the sarin-inhibited AChE with sarin-serine adducts 3 and 4 compared to formoximate anion was observed in the presence and absence of hydrogen bonding interactions of Gly121 and Gly122. The calculated results show that the rates of reactivation process of adduct 4 with hydroxylamine anion are 261 and 223 times faster than the formoximate anion in the absence and presence of such hydrogen bonding interactions. The DFT calculated results shed light on the importance of the adjacent carbonyl group of Glu202 for the reactivation of sarin-serine adduct, in particular with formoximate anion. The reverse reactivation reaction between hydroxylamine anion and sarin-serine adduct was found to be higher in energy compared to the other nucleophiles, which suggests that this α-nucleophile can be a good antidote agent for the reactivation process. Copyright © 2011 Elsevier Inc. All rights reserved.

  17. The Interleukin-6 inflammation pathway from cholesterol to aging – Role of statins, bisphosphonates and plant polyphenols in aging and age-related diseases

    Directory of Open Access Journals (Sweden)

    Omoigui Sota

    2007-03-01

    Full Text Available Abstract We describe the inflammation pathway from Cholesterol to Aging. Interleukin 6 mediated inflammation is implicated in age-related disorders including Atherosclerosis, Peripheral Vascular Disease, Coronary Artery Disease, Osteoporosis, Type 2 Diabetes, Dementia and Alzheimer's disease and some forms of Arthritis and Cancer. Statins and Bisphosphonates inhibit Interleukin 6 mediated inflammation indirectly through regulation of endogenous cholesterol synthesis and isoprenoid depletion. Polyphenolic compounds found in plants, fruits and vegetables inhibit Interleukin 6 mediated inflammation by direct inhibition of the signal transduction pathway. Therapeutic targets for the control of all the above diseases should include inhibition of Interleukin-6 mediated inflammation.

  18. The Electrochemistry of Organophosphorus Compounds.

    Science.gov (United States)

    1988-01-20

    of hydrogen on the electrode surface. Mechanistkc views are further developed with the addition of water resulting in the formation of...the exclusive vlide product. Furthermore, carbonvl compounds were added to the electrolyses to react with the electrochemically-generated ylides via...the Wittig reaction. The resulting olefins were found to catalytically isomerize from the Z isomer to the E isomer upon reduction. The role of water

  19. Mitochondrial dysfunction and organophosphorus compounds

    Energy Technology Data Exchange (ETDEWEB)

    Karami-Mohajeri, Somayyeh [Department of Toxicology and Pharmacology, Faculty of Pharmacy, and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Department of Toxicology and Pharmacology, Faculty of Pharmacy, and Pharmaceutical Sciences Research Center, Kerman University of Medical Sciences, Kerman (Iran, Islamic Republic of); Abdollahi, Mohammad, E-mail: Mohammad.Abdollahi@UToronto.Ca [Department of Toxicology and Pharmacology, Faculty of Pharmacy, and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of)

    2013-07-01

    Organophosphorous (OPs) pesticides are the most widely used pesticides in the agriculture and home. However, many acute or chronic poisoning reports about OPs have been published in the recent years. Mitochondria as a site of cellular oxygen consumption and energy production can be a target for OPs poisoning as a non-cholinergic mechanism of toxicity of OPs. In the present review, we have reviewed and criticized all the evidences about the mitochondrial dysfunctions as a mechanism of toxicity of OPs. For this purpose, all biochemical, molecular, and morphological data were retrieved from various studies. Some toxicities of OPs are arisen from dysfunction of mitochondrial oxidative phosphorylation through alteration of complexes I, II, III, IV and V activities and disruption of mitochondrial membrane. Reductions of adenosine triphosphate (ATP) synthesis or induction of its hydrolysis can impair the cellular energy. The OPs disrupt cellular and mitochondrial antioxidant defense, reactive oxygen species generation, and calcium uptake and promote oxidative and genotoxic damage triggering cell death via cytochrome C released from mitochondria and consequent activation of caspases. The mitochondrial dysfunction induced by OPs can be restored by use of antioxidants such as vitamin E and C, alpha-tocopherol, electron donors, and through increasing the cytosolic ATP level. However, to elucidate many aspect of mitochondrial toxicity of Ops, further studies should be performed. - Highlights: • As a non-cholinergic mechanism of toxicity, mitochondria is a target for OPs. • OPs affect action of complexes I, II, III, IV and V in the mitochondria. • OPs reduce mitochondrial ATP. • OPs promote oxidative and genotoxic damage via release of cytochrome C from mitochondria. • OP-induced mitochondrial dysfunction can be restored by increasing the cytosolic ATP.

  20. Mitochondrial dysfunction and organophosphorus compounds

    International Nuclear Information System (INIS)

    Karami-Mohajeri, Somayyeh; Abdollahi, Mohammad

    2013-01-01

    Organophosphorous (OPs) pesticides are the most widely used pesticides in the agriculture and home. However, many acute or chronic poisoning reports about OPs have been published in the recent years. Mitochondria as a site of cellular oxygen consumption and energy production can be a target for OPs poisoning as a non-cholinergic mechanism of toxicity of OPs. In the present review, we have reviewed and criticized all the evidences about the mitochondrial dysfunctions as a mechanism of toxicity of OPs. For this purpose, all biochemical, molecular, and morphological data were retrieved from various studies. Some toxicities of OPs are arisen from dysfunction of mitochondrial oxidative phosphorylation through alteration of complexes I, II, III, IV and V activities and disruption of mitochondrial membrane. Reductions of adenosine triphosphate (ATP) synthesis or induction of its hydrolysis can impair the cellular energy. The OPs disrupt cellular and mitochondrial antioxidant defense, reactive oxygen species generation, and calcium uptake and promote oxidative and genotoxic damage triggering cell death via cytochrome C released from mitochondria and consequent activation of caspases. The mitochondrial dysfunction induced by OPs can be restored by use of antioxidants such as vitamin E and C, alpha-tocopherol, electron donors, and through increasing the cytosolic ATP level. However, to elucidate many aspect of mitochondrial toxicity of Ops, further studies should be performed. - Highlights: • As a non-cholinergic mechanism of toxicity, mitochondria is a target for OPs. • OPs affect action of complexes I, II, III, IV and V in the mitochondria. • OPs reduce mitochondrial ATP. • OPs promote oxidative and genotoxic damage via release of cytochrome C from mitochondria. • OP-induced mitochondrial dysfunction can be restored by increasing the cytosolic ATP

  1. Age Spots

    Science.gov (United States)

    ... for Every Season How to Choose the Best Skin Care Products In This Section Dermatologic Surgery What is dermatologic ... for Every Season How to Choose the Best Skin Care Products Age Spots Treatment Options Learn more about treatment ...

  2. Modeling intentional inhibition of actions

    NARCIS (Netherlands)

    Thilakarathne, D.J.; Treur, J.

    2015-01-01

    Inspired by cognitive and neurological literature on action ownership and action awareness, in this paper a computational cognitive model for intentional inhibition (i.e.; the capacity to voluntarily suspend or inhibit an action) is introduced. The interplay between (positive) potential selection of

  3. Can Arousal Modulate Response Inhibition?

    Science.gov (United States)

    Weinbach, Noam; Kalanthroff, Eyal; Avnit, Amir; Henik, Avishai

    2015-01-01

    The goal of the present study was to examine if and how arousal can modulate response inhibition. Two competing hypotheses can be drawn from previous literature. One holds that alerting cues that elevate arousal should result in an impulsive response and therefore impair response inhibition. The other suggests that alerting enhances processing of…

  4. Imitation inhibition in children with Tourette syndrome.

    Science.gov (United States)

    Brandt, Valerie Cathérine; Moczydlowski, Agnes; Jonas, Melanie; Boelmans, Kai; Bäumer, Tobias; Brass, Marcel; Münchau, Alexander

    2017-08-12

    Echopraxia, that is, the open and automatic imitation of other peoples' actions, is common in patients with Gilles de la Tourette syndrome, autism spectrum disorder, and also those with frontal lobe lesions. While systematic reaction time tasks have confirmed increased automatic imitation in the latter two groups, adult patients with Tourette syndrome appear to compensate for automatic imitation tendencies by an overall slowing in response times. However, whether children with Tourette syndrome are already able to inhibit automatic imitation tendencies has not been investigated. Fifteen children with Tourette syndrome and 15 healthy children (aged 7-12 years) performed an imitation inhibition paradigm. Participants were asked to respond to an auditory cue by lifting their index finger or their little finger. Participants were simultaneously presented with either compatible or incompatible visual stimuli. Overall responses in children with Tourette syndrome were slower than in healthy children. Although responses were faster in compatible than in incompatible trials in both groups, this 'interference effect' was smaller in children with Tourette syndrome. Children with Tourette syndrome have a smaller interference effect than healthy children, indicating an enhanced ability to behaviourally control automatic imitation tendencies at the cost of reacting slower. The results suggest that children with Tourette syndrome already employ different or additional inhibition strategies compared to healthy children. © 2017 The British Psychological Society.

  5. Response inhibition in motor conversion disorder.

    Science.gov (United States)

    Voon, Valerie; Ekanayake, Vindhya; Wiggs, Edythe; Kranick, Sarah; Ameli, Rezvan; Harrison, Neil A; Hallett, Mark

    2013-05-01

    Conversion disorders (CDs) are unexplained neurological symptoms presumed to be related to a psychological issue. Studies focusing on conversion paralysis have suggested potential impairments in motor initiation or execution. Here we studied CD patients with aberrant or excessive motor movements and focused on motor response inhibition. We also assessed cognitive measures in multiple domains. We compared 30 CD patients and 30 age-, sex-, and education-matched healthy volunteers on a motor response inhibition task (go/no go), along with verbal motor response inhibition (color-word interference) and measures of attention, sustained attention, processing speed, language, memory, visuospatial processing, and executive function including planning and verbal fluency. CD patients had greater impairments in commission errors on the go/no go task (P conversion. Patients with nonepileptic seizures, a different form of conversion disorder, are commonly reported to have lower IQ and multiple cognitive deficits. Our results point toward potential differences between conversion disorder subgroups. © 2013 Movement Disorder Society. Copyright © 2013 Movement Disorder Society.

  6. Comparison of Chlorpyrifos-Oxon and Paraoxon Acetylcholinesterase Inhibition Dynamics: Potential role of a peripheral binding site

    Energy Technology Data Exchange (ETDEWEB)

    Kousba, Ahmed A.; Sultatos, L G.; Poet, Torka S.; Timchalk, Chuck

    2004-08-02

    The primary mechanism of action for organophosphorus (OP) insecticides involves the inhibition of acetylcholinesterase (AChE) by oxygenated metabolites (oxons). This inhibition has been attributed to the phosphorylation of the serine hydroxyl group located in the active site of the AChE molecule. The rate of phosphorylation is described by the bimolecular inhibitory rate constant (ki), which has been utilized for quantification of OP inhibitory capacity. It has been previously proposed that a peripheral binding site exists on the AChE molecule, which when occupied, reduces the capacity of additional oxon molecules to phosphorylate the active site. The objective of the current study was to evaluate the interaction of chlorpyrifos oxon (CPO) and paraoxon (PO) with rat brain AChE using a modified Ellman assay in conjunction with a pharmacodynamic model to further assess the dynamics of AChE inhibition and the potential role of a peripheral binding site. The ki for AChE inhibition determined at oxon concentrations of 5 x 10{sup -4} 100 nM were 0.212 and 0.0216 nM-1h-1 for CPO and PO, respectively. The spontaneous reactivation rates of the inhibited AChE for CPO and PO were 0.087 and 0.078 h-1, respectively. In contrast, the ki estimated at a low oxon concentration (1 pM) were {approx} 1,000 and 10,000 -fold higher than those determined at high CPO and PO concentrations, respectively. At these low concentrations, the ki estimates were approximately similar for both CPO and PO (180 and 250 nM-1h-1, respectively). This implies that at low exposure concentrations, both oxons exhibited similar inhibitory potency in contrast to the marked difference exhibited at higher concentrations, which is consistent with the presence of a peripheral binding site on the AChE enzyme. These results support the potential importance of a secondary binding site associated with AChE kinetics, particularly at low environmentally relevant concentrations.

  7. Premature aging

    International Nuclear Information System (INIS)

    Sassaki, Hideo

    1992-01-01

    The hypothesis that radiation may accelerate aging phenomenon has been studied extensively, using the population of A-bomb survivors. In this paper, non-specific radiation-induced premature aging is discussed with a review of the literature. Cardiac lipofuscin, papillary fibrosis, aortic extensibility, hexamine/collagen ratio in the skin and aorta, testicular changes, giant hepatic cell nucleus, and neurofibril changes have so far been studied pathologically in the context of A-bomb radiation. Only testicular sclerosis has been found to correlate with distance from the hypocenter. Suggestive correlation was found to exist between the hexamine/collagen ratio in the skin and aorta and A-bomb radiation. Grip strength and hearing ability were decreased in the group of 100 rad and the group of 50-99 rad, respectively. The other physiological data did not definitely correlate with A-bomb radiation. Laboratory data, including erythrocyte sedimentation rate, α and β globulin levels, phytohemagglutinin reaction, T cell counts, erythrocyte glycophorin-A, the incidence of cerebral stroke, ischemic heart disease, and cataract were age-dependent and correlated with A-bomb radiation. These findings indicated that the occurrence of arteriosclerosis-related diseases, changes in immunological competence, and some pathological and physiological findings altered with advancing age, suggesting the correlation with A-bomb radiation. In general, it cannot be concluded that there is a positive correlation between A-bomb radiation and the premature aging. (N.K.) 51 refs

  8. Successful ageing

    DEFF Research Database (Denmark)

    Bülow, Morten Hillgaard; Söderqvist, Thomas

    2014-01-01

    Since the late 1980s, the concept of ‘ successful ageing’ has set the frame for discourse about contemporary ageing research. Through an analysis of the reception to John W. Rowe and Robert L. Kahn's launch of the concept of ‘ successful ageing’ in 1987, this article maps out the important themes...... and discussions that have emerged from the interdisciplinary field of ageing research. These include an emphasis on interdisciplinarity; the interaction between biology, psycho-social contexts and lifestyle choices; the experiences of elderly people; life-course perspectives; optimisation and prevention...... strategies; and the importance of individual, societal and scientific conceptualisations and understandings of ageing. By presenting an account of the recent historical uses, interpretations and critiques of the concept, the article unfolds the practical and normative complexities of ‘ successful ageing’....

  9. Aging Differently

    DEFF Research Database (Denmark)

    Zajitschek, Felix; Jin, Tuo; Colchero, Fernando

    2014-01-01

    Diet effects on age-dependent mortality patterns are well documented in a large number of animal species, but studies that look at the effects of nutrient availability on late-life mortality plateaus are lacking. Here, we focus on the effect of dietary protein content (low, intermediate, and high...... based on Bayesian inference of age-specific mortality rates and found a deceleration of late-life mortality rates on all diets in males but only on the intermediate (standard) diet in females. The difference in mortality rate deceleration between males and females on extreme diets suggests...

  10. Aging Well

    DEFF Research Database (Denmark)

    Frieman, Catherine J.; Bruck, Joanna; Rebay-Salisbury, Katharina

    2017-01-01

    This article consist of several short individual articles which were solicited as responses to and reflections on Paul Treherne’s seminal meditation on Bronze Age male identity and warriorhood. Authors were asked to build on Treherne’s work and to reflect on how it had impacted their own research...

  11. Ice Ages

    Indian Academy of Sciences (India)

    that the precession of the earth's orbit caused ice ages. The precession of the earth's orbit leads to changes in the time of the year at which ... than in the southern hemisphere. ..... small increase in ocean temperature implies a large increase in.

  12. Selective inhibition of distracting input.

    Science.gov (United States)

    Noonan, MaryAnn P; Crittenden, Ben M; Jensen, Ole; Stokes, Mark G

    2017-10-16

    We review a series of studies exploring distractor suppression. It is often assumed that preparatory distractor suppression is controlled via top-down mechanisms of attention akin to those that prepare brain areas for target enhancement. Here, we consider two alternative mechanisms: secondary inhibition and expectation suppression within a predictive coding framework. We draw on behavioural studies, evidence from neuroimaging and some animal studies. We conclude that there is very limited evidence for selective top-down control of preparatory inhibition. By contrast, we argue that distractor suppression often relies secondary inhibition of non-target items (relatively non-selective inhibition) and on statistical regularities of the environment, learned through direct experience. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  13. [Concepts of inhibition in psychiatry].

    Science.gov (United States)

    Auroux, Y; Bourrat, M M; Brun, J P

    1978-01-01

    Following a historical approach, the authors first describe the original development of the concept of inhibition in neurophysiology and then analyze the subsequent adaptations made in psychiatry around such concept including those of: -- Pavlov, Hull, Watson and the behaviorists, -- Freud and the Freudian School, -- clinicians and psychopharmacologists. The concept of inhibition has thus various meanings in psychiatry. Although some unity is achieved on the semiological level, this aspect cannot explain the extent of the process.

  14. Inhibition of MMPs by alcohols

    Science.gov (United States)

    Tezvergil-Mutluay, Arzu; Agee, Kelli A.; Hoshika, Tomohiro; Uchiyama, Toshikazu; Tjäderhane, Leo; Breschi, Lorenzo; Mazzoni, Annalisa; Thompson, Jeremy M.; McCracken, Courtney E.; Looney, Stephen W.; Tay, Franklin R.; Pashley, David H.

    2011-01-01

    Objectives While screening the activity of potential inhibitors of matrix metalloproteinases (MMPs), due to the limited water solubility of some of the compounds, they had to be solubilized in ethanol. When ethanol solvent controls were run, they were found to partially inhibit MMPs. Thus, the purpose of this study was to compare the MMP-inhibitory activity of a series of alcohols. Methods The possible inhibitory activity of a series of alcohols was measured against soluble rhMMP-9 and insoluble matrix-bound endogenous MMPs of dentin in completely demineralized dentin. Increasing concentrations (0.17, 0.86, 1.71 and 4.28 moles/L) of a homologous series of alcohols (i.e. methanol, ethanol, propanols, butanols, pentanols, hexanols, the ethanol ester of methacrylic acid, heptanols and octanol) were compared to ethanediol, and propanediol by regression analysis to calculate the molar concentration required to inhibit MMPs by 50% (i.e. the IC50). Results Using two different MMP models, alcohols were shown to inhibit rhMMP-9 and the endogenous proteases of dentin matrix in a dose-dependent manner. The degree of MMP inhibition by alcohols increased with chain length up to 4 methylene groups. Based on the molar concentration required to inhibit rhMMP-9 fifty percent, 2-hydroxyethylmethacrylate (HEMA), 3-hexanol, 3-heptanol and 1-octanol gave the strongest inhibition. Significance The results indicate that alcohols with 4 methylene groups inhibit MMPs more effectively than methanol or ethanol. MMP inhibition was inversely related to the Hoy's solubility parameter for hydrogen bonding forces of the alcohols (i.e. to their hydrophilicity). PMID:21676453

  15. Aging Perspectives

    OpenAIRE

    Theodore D Cosco; David Brehme; Nora Grigoruta; Lisa-Katrin Kaufmann; Liis Lemsalu; Ruth Meex; Angela Schuurmans; Neslihan Sener

    2014-01-01

    Despite the proliferation of successful ageing (SA) research, the literature is dominated by researcher-driven Anglophone conceptualisations. To date, lay perspectives of SA have not been examined in Europe or Turkey. The current study aims to conduct a mixed-methods examination of conceptualisations of SA in seven underrepresented countries. Using snowball sampling via social media sites, an online survey consisting of established closed-ended and open-ended items – translated into seven lan...

  16. Healthy ageing

    DEFF Research Database (Denmark)

    Harrison, Adrian Paul; Brüggemann, Dagmar Adeline; Bartels, Else Marie

    2009-01-01

    The study employed mechanical stretching in vitro of sections of abdominal aorta of elderly mice to investigate any benefits of oral treatment with alpha-ketoglutarate (AKG) on arterial elasticity. Eighteen female mice (50-weeks-old) were assigned to a control (2% w/v) Na2-AKG or (2% w/v) a Ca-AK...... investigation as a candidate for therapies targeting arterial stiffening with age....

  17. Inhibition of the prostaglandin E2 receptor EP2 prevents status epilepticus-induced deficits in the novel object recognition task in rats

    Science.gov (United States)

    Rojas, Asheebo; Ganesh, Thota; Manji, Zahra; O’neill, Theon; Dingledine, Raymond

    2016-01-01

    Survivors of exposure to an organophosphorus nerve agent may develop a number of complications including long-term cognitive deficits (Miyaki et al., 2005; Nishiwaki et al., 2001). We recently demonstrated that inhibition of the prostaglandin E2 receptor, EP2, attenuates neuroinflammation and neurodegeneration caused by status epilepticus (SE) induced by the soman analog, diisopropylfluorophosphate (DFP), which manifest within hours to days of the initial insult. Here, we tested the hypothesis that DFP exposure leads to a loss of cognitive function in rats that is blocked by early, transient EP2 inhibition. Adult male Sprague-Dawley rats were administered vehicle or the competitive EP2 antagonist, TG6-10-1, (ip) at various times relative to DFP-induced SE. DFP administration resulted in prolonged seizure activity as demonstrated by cortical electroencephalography (EEG). A single intraperitoneal injection of TG6-10-1 or vehicle 1 h prior to DFP did not alter the development of seizures, the latency to SE or the duration of SE. Rats administered six injections of TG6-10-1 starting 90 min after the onset of DFP-induced SE could discriminate between a novel and familiar object 6–12 weeks after SE, unlike vehicle treated rats which showed no preference for the novel object. By contrast, behavioral changes in the light-dark box and open field assays were not affected by TG6-10-1. Delayed mortality after DFP was also unaffected by TG6-10-1. Thus, selective inhibition of the EP2 receptor may prevent SE-induced memory impairment in rats caused by exposure to a high dose of DFP. PMID:27477533

  18. Golden