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Disruption of selenium transport and function is a major contributor to mercury toxicity in zebrafish larvae

Mercury is one of the most toxic elements threatening the biosphere, with levels steadily rising due to both natural and human activities. Selenium is an essential micronutrient, required for normal development and functioning of many organisms. While selenium is known to counteract mercury's toxicity under some conditions, to date information about the mercury-selenium relationship is fragmented

Rethinking the Minamata Tragedy : What Mercury Species was really Responsible?

Industrial release of mercury into the local Minamata environment with consequent poisoning of local communities through contaminated fish and shellfish consumption is considered the classic case of environmental mercury poisoning. However, the mercury species in the factory effluent has proved controversial, originally suggested as inorganic, and more recently as methylmercury species. We used ne

X-ray spectroscopy and imaging of selenium in living systems

BACKGROUND: Selenium is an essential element with a rich and varied chemistry in living organisms. It plays a variety of important roles ranging from being essential in enzymes that are critical for redox homeostasis to acting as a deterrent for herbivory in hyperaccumulating plants. Despite its importance there are many open questions, especially related to its chemistry in situ within living org

Remarkable differences in the biochemical fate of Cd2+, Hg2+, CH3Hg+ and thimerosal in red blood cell lysate

Humans are environmentally exposed to potentially toxic Cd and Hg species and to the Hg compound thimerosal (THI), an antibactericidal vaccine additive. Previous studies have revealed that Cd2+, Hg2+ and CH3Hg+ are taken up by red blood cells (RBCs) and bind to cytosolic glutathione (GSH) and/or hemoglobin (Hb). Since interactions in the cytosol of RBCs may be linked to their hemolysis, a more com

Distribution of selenium in zebrafish larvae after exposure to organic and inorganic selenium forms

Selenium is an essential micronutrient for many organisms, and in vertebrates has a variety of roles associated with protection from reactive oxygen species. Over the past two decades there have been conflicting reports upon human health benefits and detriments arising from consumption of selenium dietary supplements. Thus, early studies report a decrease in the incidence of certain types of cance

Interaction of mercury and selenium in the larval stage zebrafish vertebrate model

The compounds of mercury can be more toxic than those of any other non-radioactive heavy element. Despite this, environmental mercury pollution and human exposure to mercury are widespread, and are increasing. While the unusual ability of selenium to cancel the toxicity of mercury compounds has been known for nearly five decades, only recently have some aspects of the molecular mechanisms begun to

Phenylthiourea alters toxicity of mercury compounds in zebrafish larvae

In recent years larval stage zebrafish have been emerging as a standard vertebrate model in a number of fields, ranging from developmental biology to pharmacology and toxicology. The tyrosinase inhibitor 1-phenyl-2-thiourea (PTU) is used very widely with larval zebrafish to generate essentially transparent organisms through inhibition of melanogenesis, which has enabled many elegant studies in are

Proteomics of Desulfovibrio desulfuricans and X-ray absorption spectroscopy to investigate mercury methylation in the presence of selenium

The effects of mercury added as Hg(2+) and selenium as selenite to cultures of the sulfate reducing bacterium Desulfovibrio desulfuricans were investigated under controlled laboratory conditions. There was no significant difference in the growth curves in comparison to control except in the 0.5 μM Hg-6.3 μM Se combined system in which Hg methylation was significantly reduced. A significant decreas

The impact of physician migration on mortality in low and middle-income countries : An economic modelling study

Background The WHO estimates a global shortage of 2.8 million physicians, with severe deficiencies especially in low and middle-income countries (LMIC). The unequitable distribution of physicians worldwide is further exacerbated by the migration of physicians from LMICs to high-income countries (HIC). This large-scale migration has numerous economic consequences which include increased mortality a

Measurement of J/ψ production in association with a W ± boson with pp data at 8 TeV

Results are presented from the measurement by ATLAS of long-range (| Δ η| > 2) dihadron angular correlations in s=8 and 13 TeV pp collisions containing a Z boson. The analysis is performed using 19.4 fb - 1 of s=8 TeV data recorded during Run 1 of the LHC and 36.1 fb - 1 of s=13 TeV data recorded during Run 2. Two-particle correlation functions are measured as a function of relative azimuthal angl

Synchrotron X-ray absorption spectroscopy analysis of arsenic chemical speciation in human nail clippings

Environmental context Chronic ingestion of arsenic leads to its accumulation in keratinous tissues, which can represent a risk factor for developing cancer. We use synchrotron X-ray absorption spectroscopy to investigate chemical bonding of arsenic in the keratins from nail clippings of volunteers from areas in Atlantic Canada with low-to-moderate arsenic contamination of drinking water. The study

From policy to misery? The state agricultural farms vs. 'the rural'

1989 was a turning point in the socio-economic development in the former Eastern bloc, initiating a systemic transformation that affected the society at large. It also contributed to the crystallisation of certain cultural landscapes, hitherto largely illegible due to the inhibition of spatial processes encountered during socialism. In Poland, after a quarter-century of a free market economy, the

Modeling the formation of InP/GaxIn1-xP axial nanowire heterostructures

A model is developed to depict the formation of InP/GaxIn1-xP axial heterostructures in self-catalyzed GaxIn1-xP nanowires. The composition profiles of the InP/GaxIn1-xP axial heterostructure are calculated taking into account elastic stresses. It is shown that the InP/GaxIn1-xP axial heterojunction width at the growth temperature of 450°C is larger than 12 monolayers for nanowires with the radius

Real-Time Deployment Aspects of C-Band and Millimeter-Wave 5G-NR Systems

Fifth-generation (5G) new radio (NR) deployments are being rolled out in both the C–band (3.3 - 5.0 GHz) and millimeter-wave (mmWave) band (24.5 - 29.5 GHz). For outdoor scenarios, the C–band is expected to provide wide area coverage and throughput uniformity, whereas the mmWave band is expected to provide ultra-high throughput to dedicated areas within the C-band coverage. Due to the differences

Simulated life-threatening emergency during robot-assisted surgery

Background: With the increasing use of robot-assisted techniques for urologic and gynecologic surgery in patients with severe comorbidities, the risk of a critical incidence during surgery increases. Due to limited access to the patient the start of effective measures to treat a life-threatening emergency could be delayed. Therefore, we tested the management of an acute emergency in an operating r

Super‐Resolution Infrared Imaging of Polymorphic Amyloid Aggregates Directly in Neurons

Loss of memory during Alzheimer's disease (AD), a fatal neurodegenerative disorder, is associated with neuronal loss and the aggregation of amyloid proteins into neurotoxic β‐sheet enriched structures. However, the mechanism of amyloid protein aggregation is still not well understood due to many challenges when studying the endogenous amyloid structures in neurons or in brain tissue. Available met