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Benzotriazole is antiestrogenic in vitro but not in vivo
Copyright Ā© 2007 SETAC. This is the accepted version of the following article: Harris et al (2007), "Benzotriazole is antiestrogenic in vitro but not in vivo", Environmental Toxicology and Chemistry, 26(11), 2367ā2372, which has been published in final form at the link below.Benzotriazole (BT) is an anticorrosive agent well known for its use in aircraft deicing and antifreeze fluids but also used in dishwasher detergents. It is highly persistent in the environment; therefore, BT is frequently found in runoff emanating from large airports as well as in the surrounding groundwater. In addition, BT has recently been found to be ubiquitous in Swiss wastewater treatment plant effluents and their receiving waters; however, very little chronic toxicity data is available on which to base a sound ecological risk assessment of this chemical. In vitro assays conducted using a recombinant yeast (anti-) estrogen assay indicated that BT possessed clear antiestrogenic properties. This chemical was approximately 100-fold less potent than Tamoxifen, which was used as a positive control. A subsequent in vivo study, however, involving analysis of vitellogenin induction and somatic indices in adult fathead minnows (Pimephales promelas) exposed to BT at concentrations of 10, 100, and 1,000 Ī¼g/L for two weeks showed no evidence of antiestrogenic activity by this compound. The possibility exists that higher concentrations of BT may yet induce the type of activity observed in vitro, although the concentrations used here already far exceed those reported in surface-water samples. Furthermore, adverse effects may be observed in fish or other organisms exposed to BT for a longer period than employed here, although such studies are costly and unlikely to be included in standard risk assessment procedures. A rigorous investigation of the chronic toxicity of BT is imperative
Aquaculture diversification in South America: general views and facts and case studies of the Republic of Chile and the Federative Republic of Brazil.
Aquaculture and aquaculture diversification in South America: Facts and figures. Diversification of aquaculture in South America: a few figures and concepts. Aquaculture and aquaculture diversification in the Republic of Chile: Current situation, production models and strategies. The aquaculture diversification process in the Republic of Chile: recent history and current status. Diversification and the role of government and private industry. Technology and expertise, markets, institutional facilities and governance as drivers and/or constraints to aquaculture diversification in the Republic of Chile. The future of aquaculture diversification in the Republic of Chile. Aquaculture and aquaculture diversification in the Federative Republic of Brazil: Current situation and main species farmed. Recent history and current status of aquaculture diversification: Main drivers, constraints and species. The role of government, private industry and international organizations in aquaculture diversification. Technology and expertise, markets and institutional facilities as drivers and constraints. The future of aquaculture diversification: Main concerns, opportunities, restrictions, main species to consider.bitstream/item/164749/1/CNPASA-2017-fao.pd
Risk assessment of deoxynivalenol in high-risk area of China by human biomonitoring using an improved high throughput UPLC-MS/MS method
A risk assessment of deoxynivalenol (DON) was recently conducted for the residents in Henan province, China, where wheat as the staple food are highly consumed. A high-throughput sensitive UPLC-MS/MS method following 96-well Ī¼Elution solid-phase extraction (SPE) were developed and validated for the determination of DON biomarkers in human urine. Isotope labelled internal standard, Ā¹Ā³C-DON, was used for accurate quantification. Urinary samples collected from 151 healthy Chinese aged 2ā78 years were processed with and without enzyme hydrolysis to determine total and free biomarkers, respectively. DON, and de-epoxy-deoxynivalenol (DOM-1) to a lesser extent, can be frequently detected in these samples both with and without enzyme hydrolysis. Free DOM-1 was detected at low level in human urine for the first time. Total DON was detected in all samples with a mean concentration at 47.6 ng mLā»Ā¹. The mean and median probable daily intakes (PDI) for the whole participants, estimated to be 1.61āĪ¼g/kg bw and 1.10āĪ¼g/kg bw, both exceeded the PMTDI (1āĪ¼g/kg bw/day), indicating a potential risk for the residents in this area, especially for children and adolescents
G55.0+0.3: A Highly Evolved Supernova Remnant
Multi-frequency analysis has revealed the presence of a new supernova
remnant, G55.0+0.3, in the Galactic plane. A kinematic distance of 14 kpc has
been measured from HI spectral line data. The faint, clumpy half-shell is
non-thermal and has a physical radius of 70 pc. Using an evolutionary model,
the age of the remnant is estimated to be on the order of one million years,
which exceeds conventional limits by a factor of five. The remnant may be
associated with the nearby pulsar J1932+2020, which has a spin-down age of 1.1
million years. This work implies that the radiative lifetimes of remnants could
be much longer than previously suggested.Comment: 27 pages, 7 figures in 9 files (figures 1 and 2 require 2 files
each), Accepted for publication in The Astrophysical Journal (Jan. 20, 1998
volume
A Longitudinal Analysis of the Indirect Effect of Violence Exposure on Future Orientation Through Perceived Stress and the Buffering Effect of Family Participation
Exposure to violence (ETV) during adolescence has been associated with negative effects in later life, and may negatively affect an individualās future orientation. Future orientation has important health implications and warrants being studied. Yet, few researchers have examined how ETV affects an individualās future orientation as a young adult. The purpose of this study was to examine the indirect effect of ETV during adolescence on future orientation as a young adult through perceived stress. We also tested the moderating effect of family participation on the relationship between perceived stress and future orientation. Longitudinal data from a sample of 316 African American participants (42.10% male and 57.90% female, MageĀ =Ā 14.76 at Wave 1) from low socioeconomic backgrounds recruited from a Midwestern school district were used in the analysis. Multigroup structural equationĀ modeling (SEM) was used to test our hypotheses. Our findings indicated that greater ETV during adolescence is associated with higher levels of perceived stress and, in turn, a more negative outlook on oneās future as a young adult. ThisĀ indirect effect occurred for individuals with lowerĀ family participation, but was not evident for individuals withĀ greater family participation. These findings provide important implications for youth development interventions.HighlightsWe examined how ETV relates to a positive outcome while most researchers focus on negative outcomes.We studied the effects of ETV on future orientation longitudinally.Our findings demonstrate violence exposure to affect future orientation through perceived stress.Our results show that family participation is important for buffering negative effects of stress.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146486/1/ajcp12254.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146486/2/ajcp12254_am.pd
Common Aquatic Pollutants Modify Hemocyte Immune Responses in Biomphalaria glabrata
Disruptions to reproductive health in wildlife species inhabiting polluted environments is often found to occur alongside compromised immunity. However, research on impacts of aquatic pollution on freshwater mollusc immune responses is limited despite their importance as vectors of disease (Schistosomiasis) in humans, cattle and wild mammals. We developed an in vitro ātool-kitā of well-characterized quantitative immune tests using Biomphalaria glabrata hemocytes. We exposed hemocytes to environmentally-relevant concentrations of common aquatic pollutants (17-estradiol, Bisphenol-A and p,pā-DDE) and measured key innate immune responses including motility, phagocytosis and encapsulation. Additionally, we tested an extract of a typical domestic tertiary treated effluent as representative of a āreal-worldā mixture of chemicals. Encapsulation responses were stimulated by p,pā-DDE at low-doses but were suppressed at higher doses. Concentrations of BPA (above 200 ng/ml) and p,pā-DDE (above 500 ng/ml) significantly inhibited phagocytosis compared to controls, whilst hemocyte motility was reduced by all test chemicals and the effluent extract in a dose-dependent manner. All responses occurred at chemical concentrations considered to be below the cytotoxic thresholds of hemocytes. This is the first time a suite of in vitro tests has been developed specifically in B. glabrata with the purpose of investigating the impacts of chemical pollutants and an effluent extract on immunity. Our findings indicate that common aquatic pollutants alter innate immune responses in B. glabrata, suggesting that common aquatic pollutants may be a critical, yet overlooked, factor impacting disease by modulating the dynamics of parasite transmission between molluscs and humans.The studentship supporting this research was awarded by the UK Natural Environment Research Council (NERC)
Estimating spatiotemporally varying malaria reproduction numbers in a near elimination setting
In 2016 the World Health Organization identified 21 countries that could eliminate malaria by 2020. Monitoring progress towards this goal requires tracking ongoing transmission. Here we develop methods that estimate individual reproduction numbers and their variation through time and space. Individual reproduction numbers, Rc, describe the state of transmission at a point in time and differ from mean reproduction numbers, which are averages of the number of people infected by a typical case. We assess elimination progress in El Salvador using data for confirmed cases of malaria from 2010 to 2016. Our results demonstrate that whilst the average number of secondary malaria cases was below one (0.61, 95% CI 0.55ā0.65), individual reproduction numbers often exceeded one. We estimate a decline in Rc between 2010 and 2016. However we also show that if importation is maintained at the same rate, the country may not achieve malaria elimination by 2020
Procedural Factors Associated With Percutaneous Coronary Intervention-Related Ischemic Stroke
ObjectivesThis study sought to determine whether procedural factors during percutaneous coronary intervention (PCI) are associated with the occurrence of ischemic stroke or transient ischemic attack (PCI-stroke).BackgroundStroke is a devastating complication of PCI. Demographic predictors are nonmodifiable. Whether PCI-stroke is associated with procedural factors, which may be modifiable, is unknown.MethodsWe performed a single-center retrospective study of 21,497 PCI hospitalizations between 1994 and 2008. We compared procedural factors from patients who suffered an ischemic stroke or transient ischemic attack related to PCI (n = 79) and a control group (n = 158), and matched them 2:1 based on a predicted probability of stroke developed from a logistic regression model.ResultsPCI-stroke procedures involved the use of more catheters (median: 3 [quarter (Q) 1, Q3: 3, 4] vs. 3 [Q1, Q3: 2, 3], p < 0.001), greater contrast volumes (250 ml vs. 218 ml, p = 0.006), and larger guide caliber (median: 7-F [Q1, Q3: 6, 8] vs. 6-F [Q1, Q3: 6, 8], p < 0.001). The number of lesions attempted (1.7 Ā± 0.8 vs. 1.5 Ā± 0.8, p = 0.14) and stents placed (1.4 Ā± 1.2 vs. 1.2 Ā± 1.1, p = 0.35) were similar between groups, but PCI-stroke patients were more likely to have undergone rotational atherectomy (10% vs. 3%, p = 0.029). Overall procedural success was lower in the PCI-stroke group compared with controls (71% vs. 85%, p = 0.017). Evaluation of the entire PCI population revealed no difference in the rate of PCI-stroke between radial and femoral approaches (0.4% vs. 0.4%, p = 0.78).ConclusionsIschemic stroke related to PCI is associated with potentially modifiable technical parameters. Careful procedural planning is warranted, particularly in patients at increased risk
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