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Cell Jun 1999
Review
Topics: Amino Acid Sequence; Animals; Binding Sites; Blood Proteins; Crystallography, X-Ray; Inositol Phosphates; Molecular Sequence Data; Organophosphates; Phosphatidylinositols; Phosphoproteins; Protein Conformation
PubMed: 10399908
DOI: 10.1016/s0092-8674(00)80792-8 -
Annals of Biomedical Engineering Jan 2013We develop a mathematical model of nanoparticles depositing onto and penetrating into a biofilm grown in a parallel-plate flow cell. We carry out deposition experiments...
We develop a mathematical model of nanoparticles depositing onto and penetrating into a biofilm grown in a parallel-plate flow cell. We carry out deposition experiments in a flow cell to support the modeling. The modeling and the experiments are motivated by the potential use of polymer nanoparticles as part of a treatment strategy for killing biofilms infecting the deep passages in the lungs. In the experiments and model, a fluid carrying polymer nanoparticles is injected into a parallel-plate flow cell in which a biofilm has grown over the bottom plate. The model consists of a system of transport equations describing the deposition and diffusion of nanoparticles. Standard asymptotic techniques that exploit the aspect ratio of the flow cell are applied to reduce the model to two coupled partial differential equations. We perform numerical simulations using the reduced model. We compare the experimental observations with the simulation results to estimate the nanoparticle sticking coefficient and the diffusion coefficient of the nanoparticles in the biofilm. The distributions of nanoparticles through the thickness of the biofilm are consistent with diffusive transport, and uniform distributions through the thickness are achieved in about four hours. Nanoparticle deposition does not appear to be strongly influenced by the flow rate in the cell for the low flow rates considered.
Topics: Biofilms; Chitosan; Diffusion; Drug Delivery Systems; Lung; Models, Theoretical; Mucus; Nanoparticles; Organophosphates; Polyethylene Glycols; Polymers; Pseudomonas aeruginosa
PubMed: 22878680
DOI: 10.1007/s10439-012-0626-0 -
Neurotherapeutics : the Journal of the... Apr 2014Transthyretin (TTR) amyloidoses comprise a wide spectrum of acquired and hereditary diseases triggered by extracellular deposition of toxic TTR aggregates in various...
Transthyretin (TTR) amyloidoses comprise a wide spectrum of acquired and hereditary diseases triggered by extracellular deposition of toxic TTR aggregates in various organs. Despite recent advances regarding the elucidation of the molecular mechanisms underlying TTR misfolding and pathogenic self-assembly, there is still no effective therapy for treatment of these fatal disorders. Recently, the "molecular tweezers", CLR01, has been reported to inhibit self-assembly and toxicity of different amyloidogenic proteins in vitro, including TTR, by interfering with hydrophobic and electrostatic interactions known to play an important role in the aggregation process. In addition, CLR01 showed therapeutic effects in animal models of Alzheimer's disease and Parkinson's disease. Here, we assessed the ability of CLR01 to modulate TTR misfolding and aggregation in cell culture and in an animal model. In cell culture assays we found that CLR01 inhibited TTR oligomerization in the conditioned medium and alleviated TTR-induced neurotoxicity by redirecting TTR aggregation into the formation of innocuous assemblies. To determine whether CLR01 was effective in vivo, we tested the compound in mice expressing TTR V30M, a model of familial amyloidotic polyneuropathy, which recapitulates the main pathological features of the human disease. Immunohistochemical and Western blot analyses showed a significant decrease in TTR burden in the gastrointestinal tract and the peripheral nervous system in mice treated with CLR01, with a concomitant reduction in aggregate-induced endoplasmic reticulum stress response, protein oxidation, and apoptosis. Taken together, our preclinical data suggest that CLR01 is a promising lead compound for development of innovative, disease-modifying therapy for TTR amyloidosis.
Topics: Amyloid Neuropathies, Familial; Animals; Bridged-Ring Compounds; Cells, Cultured; Colon; Disease Models, Animal; Ganglia, Spinal; Humans; Mice; Mice, Transgenic; Organophosphates; Prealbumin; Stomach
PubMed: 24459092
DOI: 10.1007/s13311-013-0256-8 -
Organic & Biomolecular Chemistry Jan 2020Through the combined action of palladium catalysts and chiral phosphoric acids (CPAs) a variety of catalytic asymmetric reactions have been realized during the past... (Review)
Review
Through the combined action of palladium catalysts and chiral phosphoric acids (CPAs) a variety of catalytic asymmetric reactions have been realized during the past decade, including allylation, alkene functionalization, and C-H activation. This review surveys key examples across these various reaction types and examines the different mechanisms by which CPAs can affect stereoinduction in these reaction systems.
Topics: Catalysis; Organic Chemicals; Organophosphates; Palladium; Stereoisomerism
PubMed: 31907504
DOI: 10.1039/c9ob02205h -
Environment International Jul 2022Owing to increasing concerns about the toxicity of alkyl organophosphate triesters (OPTEs), it is necessary to comprehensively profile alkyl OPTEs in the environment. In...
Owing to increasing concerns about the toxicity of alkyl organophosphate triesters (OPTEs), it is necessary to comprehensively profile alkyl OPTEs in the environment. In this study, we conducted a nontarget analysis using high-resolution mass spectrometry to newly identify alkyl OPTEs in house dust samples collected in North China. Data-independent acquisition mode directed by the characteristic phosphate fragment was used. Nine alkyl OPTEs were newly identified, namely tridecyl phosphate (TDeP), dioctyl tetradecyl phosphate, tridodecyl phosphate (TDoP), dioctyl butoxyethoxyethyl phosphate (DOBEEP), dioctyl (oxo)butoxypropyl phosphate (DOOBPP), dioctyl hydroxyethoxyethoxyethyl phosphate (DOHEEEP), didodecyl hydroxyethoxyethyl phosphate (DDoHEEP), tetradecyl dodecyl hydroxyethoxyethyl phosphate (TDoHEEP), and bis(2-butoxyethyl) hydroxyethyl phosphate (BBOEHEP). BBOEHEP was fully identified by comparison to an authentic standard, and the others were tentative structures (level 3). Eight of them (not DOHEEEP) exhibited detection frequencies between 89% and 100% in the 45 samples, and (semi-)quantitation revealed that their median concentrations and ranges were: TDoP (35.1 ng/g, 8.21-111 ng/g), DOBEEP (29.3 ng/g, 2.56-5191 ng/g), DOOBPP (13.6 ng/g, 1.38-2128 ng/g), BBOEHEP (5.79 ng/g, not detected (ND)-861 ng/g), TDeP (4.10 ng/g, 1.34-39.2 ng/g), DDoHEEP (3.26 ng/g, ND-41.5 ng/g), TDoHEEP (2.09 ng/g, ND-29.5 ng/g), and DOTP (0.93 ng/g, ND-169 ng/g). Moreover, TDeP, TDoP, DOBEEP, DOOBPP, and BBOEHEP were found in SRM2585 (standard house dust). These data revealed the widespread occurrence of alkyl OPTEs with high concentrations in the indoor environment.
Topics: Air Pollution, Indoor; Dust; Environmental Monitoring; Flame Retardants; Mass Spectrometry; Organophosphates; Phosphates
PubMed: 35687946
DOI: 10.1016/j.envint.2022.107333 -
Parasites & Vectors Dec 2023Taiwan's warm and humid climate and dense population provide a suitable environment for the breeding of pests. The three major urban insects in Taiwan are house flies,...
BACKGROUND
Taiwan's warm and humid climate and dense population provide a suitable environment for the breeding of pests. The three major urban insects in Taiwan are house flies, cockroaches, and mosquitoes. In cases where a disease outbreak or high pest density necessitates chemical control, selecting the most effective insecticide is crucial. The resistance of pests to the selected environmental insecticide must be rapidly assessed to achieve effective chemical control and reduce environmental pollution.
METHODS
In this study, we evaluated the resistance of various pests, namely, house flies (Musca domestica L.), cockroaches (Blattella germanica L. and Periplaneta americana), and mosquitoes (Aedes aegypti and Ae. albopictus) against 10 commonly used insecticides. Rapid insecticide resistance bioassays were performed using discriminating doses or concentrations of the active ingredients of insecticides.
RESULTS
Five field strains of M. domestica (L.) are resistant to all 10 commonly used insecticides and exhibit cross- and multiple resistance to four types of pyrethroids and three types of organophosphates, propoxur, fipronil, and imidacloprid. None of the five field strains of P. americana are resistant to any of the tested insecticides, and only one strain of B. germanica (L.) is resistant to permethrin. One strain of Ae. albopictus is resistant to pirimiphos-methyl, whereas five strains of Ae. aegypti exhibit multiple resistance to pyrethroids, organophosphates, and other insecticides.
CONCLUSIONS
In the event of a disease outbreak or high pest density, rapid insecticide resistance bioassays may be performed using discriminating doses or concentrations to achieve precise and effective chemical control, reduce environmental pollution, and increase control efficacy.
Topics: Animals; Insecticides; Insecticide Resistance; Taiwan; Pyrethrins; Aedes; Cockroaches; Organophosphates; Biological Assay
PubMed: 38042818
DOI: 10.1186/s13071-023-06055-x -
International Journal of Molecular... Jun 2019Organophosphate flame retardants (OPFRs) have been detected in various environmental matrices and have been identified as emerging contaminants (EC). Given the adverse... (Review)
Review
A Review of a Class of Emerging Contaminants: The Classification, Distribution, Intensity of Consumption, Synthesis Routes, Environmental Effects and Expectation of Pollution Abatement to Organophosphate Flame Retardants (OPFRs).
Organophosphate flame retardants (OPFRs) have been detected in various environmental matrices and have been identified as emerging contaminants (EC). Given the adverse influence of OPFRs, many researchers have focused on the absorption, bioaccumulation, metabolism, and internal exposure processes of OPFRs in animals and humans. This paper first reviews the evolution of various types of flame retardants (FRs) and the environmental pollution of OPFRs, the different absorption pathways of OPFRs by animals and humans (such as inhalation, ingestion, skin absorption and absorption), and then summarizes the environmental impacts of OPFRs, including their biological toxicity, bioaccumulation, persistence, migration, endocrine disruption and carcinogenicity. Based on limited available data and results, this study also summarizes the bioaccumulation and biomagnification potential of OPFRs in different types of biological and food nets. In addition, a new governance idea for the replacement of existing OPFRs from the source is proposed, seeking environmentally friendly alternatives to OPFRs in order to provide new ideas and theoretical guidance for the removal of OPFRs.
Topics: Animals; Environmental Pollutants; Environmental Pollution; Esters; Flame Retardants; Humans; Molecular Structure; Organophosphates; Organophosphorus Compounds
PubMed: 31212857
DOI: 10.3390/ijms20122874 -
International Journal of Hygiene and... Aug 2022Endocrine-disrupting chemicals may alter glucose homeostasis, especially during pregnancy. Biomonitoring studies suggest ubiquitous human exposure to organophosphate...
BACKGROUND
Endocrine-disrupting chemicals may alter glucose homeostasis, especially during pregnancy. Biomonitoring studies suggest ubiquitous human exposure to organophosphate esters (OPEs), chemicals with endocrine-disrupting capabilities. Few studies have examined the association between maternal exposure to OPEs and blood glucose during pregnancy.
METHODS
With data from 301 pregnant women in the Health Outcomes and Measures of the Environment (HOME) Study, a prospective pregnancy and birth cohort in Cincinnati, Ohio, USA, we examined whether OPE concentrations were associated with changes in blood glucose. We quantified four OPE metabolites in maternal spot urine samples collected at 16- and 26-weeks pregnancy. We extracted results from the glucose challenge test (GCT) and oral glucose tolerance test (OGTT) via medical chart review. Women with GCT ≥ 140 mg/dL or any abnormal values in OGTT (≥ 95 mg/dL fasting glucose, ≥ 180 mg/dL 1-h glucose, ≥ 155 mg/dL 2-h glucose, ≥ 140 mg/dL 3-h glucose) were defined as having elevated glucose levels. We used linear regression and Bayesian Kernel Machine Regression (BKMR) to estimate the associations of individual OPE metabolites and OPE mixtures with blood glucose levels during pregnancy. We used modified Poisson regression to estimate the associations of OPE metabolite concentrations with elevated glucose levels. We further examined effect measure modification by maternal characteristics (age, pre-pregnancy body mass index [BMI], and race/ethnicity).
RESULTS
Diphenyl phosphate (DPHP) had the highest geometric mean concentration of the urinary OPE metabolites (1.83 μg/L at 16 weeks, 1.24 μg/L at 26 weeks). Thirty women (10.0%) had elevated glucose levels. Individual OPE metabolites or their mixtures were not significantly associated with continuous GCT results. We did not observe effect measure modification by maternal age, pre-pregnancy BMI categories, or race/ethnicity. Compared with women in the 1st tertile of average DPHP of 16- and 26 weeks of pregnancy, women in the 3rd tertile tended to have a reduced risk of elevated glucose levels (RR = 0.41, 95% CI = 0.16-1.06, p for trend = 0.06).
CONCLUSION
In this cohort, maternal urinary OPE metabolite concentrations were weakly associated with blood glucose levels during pregnancy.
Topics: Bayes Theorem; Blood Glucose; Esters; Female; Humans; Organophosphates; Pregnancy; Prospective Studies
PubMed: 36029741
DOI: 10.1016/j.ijheh.2022.114026 -
International Journal of Environmental... Feb 2022Organophosphate ester flame retardants (OPFRs) are widely prevalent in the environment and are of significant concern because of their potential toxicity to human health...
Organophosphate ester flame retardants (OPFRs) are widely prevalent in the environment and are of significant concern because of their potential toxicity to human health and wildlife. In this study, the concentration, frequency, spatial distribution, potential sources, and ecological risks of OPFRs in sediments from the Jiulong River estuary and the adjacent western Taiwan Strait were investigated. Concentrations of four of the five studied OPFRs were between
ester (2,3-dibromopropyl) (TDBPP) have almost no risk, tris (clorisopropyl) phosphate (TCPP) generally has low risk, while EHDPP has moderate risk with the highest value of 0.487 in the sediments from both sites. Meanwhile, TCPP and TCEP exhibit lower theoretical health risks but are still not negligible. Overall, this work provides data to support global pollutant studies and facilitate the implementation of pollutant control strategies. Topics: China; Environmental Monitoring; Estuaries; Flame Retardants; Humans; Organophosphates; Rivers; Taiwan
PubMed: 35206636
DOI: 10.3390/ijerph19042449 -
IARC Monographs on the Evaluation of... 1990
Review
Topics: Animals; Carcinogens; Carcinogens, Environmental; Chemical Phenomena; Chemistry; Female; Flame Retardants; Mice; Mutagens; Organophosphates; Organophosphorus Compounds; Rats
PubMed: 2197455
DOI: No ID Found