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https://www.readbyqxmd.com/read/29031237/novel-methodology-for-determining-the-effect-of-adsorbates-on-human-enamel-acid-dissolution
#1
N Pechlivani, D A Devine, P D Marsh, A Mighell, S J Brookes
OBJECTIVE: The effect of various interventions on enamel demineralisation can be determined by chemically measuring mineral ions dissolved by the attacking acid. Results are usually expressed as mineral loss per surface area of enamel exposed. Acid resistant varnish or adhesive tape are typically used to delineate an area of enamel. However, enamel surface curvature, rugosity and porosity reduce the reliability of simple area measurements made at the macro scale. Our aim was to develop a simple method for investigating the effect of adsorbates on enamel demineralisation that does not rely on knowing the area of enamel exposed...
October 3, 2017: Archives of Oral Biology
https://www.readbyqxmd.com/read/29031215/comprehensive-multipathway-risk-assessment-of-chemicals-associated-with-recycled-crumb-rubber-in-synthetic-turf-fields
#2
Michael K Peterson, Julie C Lemay, Sara Pacheco Shubin, Robyn L Prueitt
BACKGROUND: Thousands of synthetic turf fields in the US are regularly used by millions of individuals (particularly children and adolescents). Although many safety assessments have concluded that there are low or negligible risks related to exposure to chemicals found in the recycled rubber used to make these fields, concerns remain about the safety of this product. Existing studies of recycled rubber's potential health risks have limitations such as small sample sizes and limited evaluation of relevant exposure pathways and scenarios...
October 11, 2017: Environmental Research
https://www.readbyqxmd.com/read/29031196/anti-edematogenic-and-anti-inflammatory-activity-of-the-essential-oil-from-croton-rhamnifolioides-leaves-and-its-major-constituent-1-8-cineole-eucalyptol
#3
Anita Oliveira Brito Pereira Bezerra Martins, Lindaiane Bezerra Rodrigues, Francisco Rafael Alves Santana Cesário, Maria Rayane Correia de Oliveira, Cicera Datiane Morais Tintino, Fyama Ferreira E Castro, Isabel Sousa Alcântara, Maria Neyze Martins Fernandes, Thaís Rodrigues de Albuquerque, Maria Sanadia Alexandre da Silva, Adriano Antunes de Sousa Araújo, Lucindo José Quintans Júniur, José Galberto Martins da Costa, Irwin Rose Alencar de Menezes, Almir Gonçalves Wanderley
The species Croton rhamnifolioides, belonging to the Croton genus, is known in ethnomedicine as "quebra faca" and is used in the treatment of stomach pain, vomiting and fever. This study aims to evaluate the anti-edematogenic and anti-inflammatory effect of Croton rhamnifolioides leaf essential oil (OEFC) and its major constituent: 1,8-cineole (eucalyptol). The essential oil was extracted from fresh leaves through a hydrodistillation system. The chemical analysis was determined by gas chromatography-mass spectrometry (GC-MS)...
October 11, 2017: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
https://www.readbyqxmd.com/read/29031119/index-analysis-and-human-health-risk-model-application-for-evaluating-ambient-air-heavy-metal-contamination-in-chemical-valley-sarnia
#4
Richard Olawoyin, Linda Schweitzer, Kuangyuan Zhang, Oladapo Okareh, Kevin Slates
The impacts of air emissions as a consequence of industrial activities around communities of human habitation have been extensively reported. This study is the first to assess potential adverse human health effects in the Chemical Valley Sarnia (CVS) area, around the St. Clair River, using health risk models, ecological and pollution indices. Large quantities of particulate matters (PM) are generated from anthropogenic activities, which contain several heavy metals in trace quantities with potentially adverse effects to humans and environmental health...
October 11, 2017: Ecotoxicology and Environmental Safety
https://www.readbyqxmd.com/read/29031118/chemical-elements-in-mediterranean-macroalgae-a-review
#5
REVIEW
Giuseppe Bonanno, Martina Orlando-Bonaca
This review analyzes the state of knowledge on the capacity of Mediterranean macroalgae to accumulate, tolerate and biomonitor macro- and micro-elements present in seawater and sediments. The results show that the investigated macroalgal species amount to c. 5.0% of all Mediterranean native Rhodophyta, Chlorophyta and Ochrophyta. The most commonly analyzed elements in algae were Pb, Cd, Zn and Cu, whereas very few studies were available for macroelements such as Ca and K. Uptake mechanisms and the factors influencing accumulation are overall well known, but the available studies are restricted to a limited number of chemical elements and algal species...
October 11, 2017: Ecotoxicology and Environmental Safety
https://www.readbyqxmd.com/read/29031112/quantitative-analysis-of-antithrombin-iii-binding-site-in-low-molecular-weight-heparins-by-exhausetive-heparinases-digestion-and-capillary-electrophoresis
#6
Mingyu Zhang, Gong Li, Yi Zhang, Jingwu Kang
The antithrombin III (ATIII)-binding site, which contains a special 3-O-sulfated, N-sulfated glucosamine residue with or without 6-O-sulfation, is mainly responsible for the anticoagulant activity of heparin. Undergoing the chemical depolymerization process, the preservation of the ATIII-binding site in low molecular weight heparins (LMWHs) are varied leading to the fluctuation of the anticoagulant activity. Herein we report a capillary electrophoresis (CE) method in combination with heparinase digestion and affinity chromatography for the measurement of molar percentage of ATIII-binding site of LMWHs...
October 6, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/29031087/characterization-of-the-radiosynthesis-and-purification-of-18-f-thk-5351-a-pet-ligand-for-neurofibrillary-tau
#7
Tobey J Betthauser, Paul A Ellison, Dhanabalan Murali, Patrick J Lao, Todd E Barnhart, Shozo Furumoto, Nobuyuki Okamura, Sterling C Johnson, Jonathan W Engle, Robert J Nickles, Bradley T Christian
This work characterizes the radiochemical synthesis, purification, and formulation of [(18)F]THK-5351, a tau PET radioligand, and develops an automated radiosynthesis routine (ELIXYS, Sofie Biosciences). Nucleophilic radiofluorination reaction was complete by 7min at 110°C with radiochemical yields proportional to precursor mass (0.1-0.5mg). Optimized HPLC purification produced radiotracer product with no chemical impurities observed on analytical HPLC in formulation. Automated radiosynthesis (ELIXYS), HPLC purification and formulation was completed in 86min producing formulated product suitable for human research use...
October 4, 2017: Applied Radiation and Isotopes
https://www.readbyqxmd.com/read/29031054/magnetic-biochar-catalyst-derived-from-biological-sludge-and-ferric-sludge-using-hydrothermal-carbonization-preparation-characterization-and-its-circulation-in-fenton-process-for-dyeing-wastewater-treatment
#8
He Zhang, Gang Xue, Hong Chen, Xiang Li
To solve sludge disposal and management problems during dyeing wastewater treatment, the produced excess biological sludge and ferric sludge were fabricated into a magnetic biochar composite (MBC) under the optimal hydrothermal carbonization (HTC) conditions. With ferric sludge mixing, the generated MBC contained paramagnetic Fe3O4, showed a smaller diameter of approximately 200 nm, a smaller pore size, a larger specific surface area and a higher carbonization degree than BC prepared using a single biological sludge process under the same HTC conditions...
October 4, 2017: Chemosphere
https://www.readbyqxmd.com/read/29031052/dispersibility-and-biotransformation-of-oils-with-different-properties-in-seawater
#9
Odd G Brakstad, Umer Farooq, Deni Ribicic, Roman Netzer
Dispersants are used to remove oils slicks from sea surfaces and to generate small oil-droplet dispersions, which may result in enhanced biodegradation of the oil. In this study, dispersibility and biodegradation of chemically dispersed oils with different physical-chemical properties (paraffinic, naphthenic and asphaltenic oils) were compared in natural temperate SW at 13 °C. All selected oils were chemically dispersible when well-known commercial dispersants were used. However, interfacial tension (IFT) studies of the dispersed oils showed different IFT properties of the oils at 13 °C, and also different leaching of the dispersants from oil droplet surfaces...
October 4, 2017: Chemosphere
https://www.readbyqxmd.com/read/29029351/development-and-application-of-a-dual-rat-and-human-ahr-activation-assay
#10
Martin R Brown, Helen Garside, Emma Thompson, Saseela Atwal, Chloe Bean, Tony Goodall, Michael Sullivan, Mark J Graham
Significant prolonged AHR activation, classically exhibited following exposure to TCDD (dioxin), can cause a variety of undesirable toxicological effects. Novel pharmaceutical chemistries also have the potential to cause activation of AHR and consequent toxicities in pre-clinical species and man. Previous methods either employed relatively expensive and low throughput primary hepatocyte dosing with PCR endpoint, or low resolution overexpressing reporter gene assays. We have developed, validated and applied an in vitro microtitre plate imaging-based medium throughput screening assay for the assessment of endogenous species-specific AHR activation potential via detection of induction of the surrogate transcriptional target Cytochrome P450 CYP1A1...
September 18, 2017: Toxicological Sciences: An Official Journal of the Society of Toxicology
https://www.readbyqxmd.com/read/29029346/botanical-compound-p-anisaldehyde-repels-larval-lone-star-tick-acari-ixodidae-and-halts-reproduction-by-gravid-adults
#11
Allan T Showler, Jessica L Harlien
The lone star tick, Amblyomma americanum (L.), widely distributed across eastern, southeastern, and midwestern regions of the United States and south into Mexico, is an obligate blood feeder that attaches to three hosts during the larval, nymphal, and adult stages. White-tailed deer and wild turkey are common hosts, as well as a wide variety of other avian and mammalian hosts. Amblyomma americanum is the most frequently reported species of tick to bite humans in the southeastern and southcentral United States, and it can transmit diseases that include erhlichiosis, rickettsiosis, tularemia, and protozoan infections...
October 4, 2017: Journal of Medical Entomology
https://www.readbyqxmd.com/read/29029336/differential-effects-of-exposure-to-single-versus-a-mixture-of-endocrine-disrupting-chemicals-on-steroidogenesis-pathway-in-mouse-testes
#12
Julio Buñay, Eduardo Larriba, Daniel Patiño-Garcia, Leonor Cruz-Fernandes, Sergio Castañeda-Zegarra, María Rodriguez-Fernandez, Jesús Del Mazo, Ricardo D Moreno
Endocrine-disrupting chemicals (EDCs) generate reproductive dysfunctions affecting the biosynthesis of steroid hormones and genes of the steroidogenic pathway. EDCs effects are mainly reported as a result of exposure to single compounds. However, humans are environmentally exposed to a mixture of EDCs. Herein, we assess chronic exposure to single alkylphenols and phthalates versus a mixture in mouse testes histology and steroidogenesis. Pregnant mice were exposed through drinking water to: 0.3 mg/Kg-body weight (BW)/day of each phthalate (DEHP, DBP, BBP), 0...
September 22, 2017: Toxicological Sciences: An Official Journal of the Society of Toxicology
https://www.readbyqxmd.com/read/29029316/the-need-for-and-the-role-of-the-toxicological-chemist-in-the-design-of-safer-chemicals
#13
Stephen C DeVito
During the past several decades there has been an ever increasing emphasis for designers of new commercial (non-pharmaceutical) chemicals to include considerations of the potential impacts a planned chemical may have on human health and the environment as part of the design of the chemical, and to design chemicals such that they possess the desired use efficacy while minimizing threats to human health and the environment. Achievement of this goal would be facilitated by the availability of individuals specifically and formally trained to design such chemicals...
September 18, 2017: Toxicological Sciences: An Official Journal of the Society of Toxicology
https://www.readbyqxmd.com/read/29029310/fragrance-allergens-linalool-and-limonene-allylic-hydroperoxides-in-skin-allergy-mechanisms-of-action-focusing-on-transcription-factor-nrf2
#14
Chloé Raffalli, Elodie Clouet, Salen Kuresepi, Marie-Hélène Damiens, Jean-Pierre Lepoittevin, Marc Pallardy, Pierre-Jacques Ferret, Elena Giménez-Arnau, Saadia Kerdine-Römer
Allergic contact dermatitis (ACD) is regarded as the most frequent expression of immunotoxicity in humans. Many odorant terpenes commonly used in fragrance compositions are considered as weak skin sensitizers, whereas some of their autoxidation products, allylic hydroperoxides, are classified as strong sensitizers according to the Local Lymph Node Assay (LLNA). However, the mechanism of their effects on the immune system remains unclear. Since dendritic cells play a key role in ACD, we studied their activation by the frequently used linalool (LINA) and limonene (LIMO), and their respective sensitizing allylic hydroperoxides (LINA-OOH, LIMO-OOH)...
September 29, 2017: Toxicological Sciences: An Official Journal of the Society of Toxicology
https://www.readbyqxmd.com/read/29029301/attractiveness-of-host-plants-at-different-growth-stage-to-kudzu-bug-megacopta-cribraria-heteroptera-plataspidae-behavioral-responses-to-whole-plant-and-constitutive-volatiles
#15
L Yang, X P Hu, E van Santen, X N Zeng
The kudzu bug, Megacopta cribraria (Fabricius), is an invasive pest of soybeans, Glycine max (L.) Merr., that has recently been detected in the United States. This study investigated whether there was a differential attraction of adult bugs to soybean growth stages, and whether the attraction was related to soybean constitutive volatiles. Greenhouse choice assays examined the behavioral orientation preference of adult bugs exposed to four growth stages of whole soybean plants: vegetative (V2), flowering (R1), pod (R3), and seed (R5)...
September 27, 2017: Journal of Economic Entomology
https://www.readbyqxmd.com/read/29029268/development-and-validation-of-a-method-for-the-detection-of-%C3%AE-and-%C3%AE-endosulfan-organochlorine-insecticide-in-calliphora-vomitoria-diptera-calliphoridae
#16
Paola A Magni, Marco Pazzi, Marco Vincenti, Valerio Converso, Ian R Dadour
Entomotoxicology studies employ analytical methods and instrumentation to detect chemical substances in carrion insects feeding from the decomposing tissues. The identification of such chemicals may determine the cause of death and may be used for the estimation of the minimum time since death. To date, the main focus of entomotoxicological studies has been the detection of drugs, whereas little information concerns the effects of pesticides on blowflies. Pesticides are generally freely available and more affordable than drugs but they can also be a home hazard and an accessible candidate poison at a crime scene...
October 4, 2017: Journal of Medical Entomology
https://www.readbyqxmd.com/read/29029251/effects-of-the-botanical-compound-p-anisaldehyde-on-horn-fly-diptera-muscidae-repellency-mortality-and-reproduction
#17
Allan T Showler, Jessica L Harlien
The horn fly, Haematobia irritans irritans (L.) (Diptera: Muscidae), is an economically important obligate blood feeder that mainly attacks cattle in Europe, Asia, and North and South America. As horn fly resistance to conventional insecticides becomes more common, alternative control tactics, such as application of bioactive botanical natural products are being investigated. p-Anisaldehyde has been found in many plant species, and it has shown effects that include mortality, attractancy, and interference with host seeking...
October 4, 2017: Journal of Medical Entomology
https://www.readbyqxmd.com/read/29029248/efficacy-of-nanoencapsulated-thymus-eriocalyx-and-thymus-kotschyanus-essential-oils-by-a-mesoporous-material-mcm-41-against-tetranychus-urticae-acari-tetranychidae
#18
Asgar Ebadollahi, Jalal Jalali Sendi, Alireza Aliakbar
Inspite of well-established potentiality of plant essential oils as biopesticides, their environmentally low persistence is considered as a hindering obstacle for its commercialization. In the present study, chemical composition and toxicity of essential oils isolated from leaves of Thymus eriocalyx and Thymus kotschyanus were evaluated against two-spotted spider mite, Tetranychus urticae. The chemicals present in the crude oil were found to be thymol (28.83%), oleic acid (11.51%), palmitic acid (8.60%), borneol (5...
September 27, 2017: Journal of Economic Entomology
https://www.readbyqxmd.com/read/29029151/combined-toxicity-of-three-essential-oils-against-aedes-aegypti-diptera-culicidae-larvae
#19
Ephantus J Muturi, Jose L Ramirez, Kenneth M Doll, Michael J Bowman
Essential oils are potential alternatives to synthetic insecticides because they have low mammalian toxicity, degrade rapidly in the environment, and possess complex mixtures of bioactive constituents with multi-modal activity against the target insect populations. Twenty-one essential oils were initially screened for their toxicity against Aedes aegypti (L.) larvae and three out of the seven most toxic essential oils (Manuka, oregano, and clove bud essential oils) were examined for their chemical composition and combined toxicity against Ae...
October 4, 2017: Journal of Medical Entomology
https://www.readbyqxmd.com/read/29029043/degradation-of-the-recalcitrant-oil-spill-components-anthracene-and-pyrene-by-a-microbially-driven-fenton-reaction
#20
Ramanan Sekar, Thomas J DiChristina
Oil spill components include a range of toxic saturated, aromatic, and polar hydrocarbons, including pyrene and anthracene. Such contaminants harm natural ecosystems, adversely affect human health, and negatively impact tourism and the fishing industries. Current physical, chemical, and biological remediation technologies are often unable to completely remove recalcitrant oil spill components, which accumulate at levels greater than regulatory limits set by the EPA. In the present study, a microbially-driven Fenton reaction, previously shown to produce hydroxyl (HO) radicals that degrade chlorinated solvents and associated solvent stabilizers, was also found to degrade source zone concentrations of the oil spill components pyrene (10 μM) and anthracene (1 μM) at initial rates of 0...
September 25, 2017: FEMS Microbiology Letters
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