Intermobility of barium, strontium, and lead in chloride and sulfate leach solutions.

Production of radionuclide-free copper concentrates is dependent on understanding and controlling the deportment of daughter radionuclides (RNs) produced from U decay, specifically Ra, Pb, and Po. Sulfuric acid leaching is currently employed in the Olympic Dam processing plant (South Australia) to remove U and fluorine from copper concentrates prior to smelting but does not adequately remove the aforementioned RN. Due to chemical similarities between lead and alkaline earth metals (including Ra), two sets of experiments were designed to understand solution interactions between Sr, Ba, and Pb at various conditions.

Effect of reduced irradiance on C uptake, gene expression and protein activity of the seagrass Zostera muelleri.

Photosynthesis in the seagrass Zostera muelleri remains poorly understood. We investigated the effect of reduced irradiance on the incorporation of C, gene expression of photosynthetic, photorespiratory and intermediates recycling genes as well as the enzymatic content and activity of Rubisco and PEPC within Z. muelleri.

Zinc and Cadmium Mapping in the Apical Shoot and Hypocotyl Tissues of Radish by High-Resolution Secondary Ion Mass Spectrometry (NanoSIMS) after Short-Term Exposure to Metal Contamination.

Zinc (as an essential phytonutrient) and cadmium (as a toxic but readily bioavailable nonessential metal for plants) share similar routes for crossing plant biomembranes, although with a substantially different potential for translocation into above-ground tissues. The in situ distribution of these metals in plant cells and tissues (particularly intensively-dividing and fast-growing areas) is poorly understood. In this study, 17-day-old radish ( L.

Zinc and cadmium mapping by NanoSIMS within the root apex after short-term exposure to metal contamination.

Zinc as a micronutrient and cadmium as a nonessential toxic element share similar pathways for entering plant tissues and thus may be antagonistic. In nutrient solution culture, 17-day-old radish (Raphanus sativus L) plants were exposed to short-term (24 h) equimolar metal contamination (2.2 µM of each Zn and total Cd) to investigate the in situ Zn/Cd distribution in the apical root tissues using high-resolution secondary ion mass spectrometry (NanoSIMS) imaging.

Intracellular speciation of gold nanorods alters the conformational dynamics of genomic DNA.

Gold nanorods are one of the most widely explored inorganic materials in nanomedicine for diagnostics, therapeutics and sensing. It has been shown that gold nanorods are not cytotoxic and localize within cytoplasmic vesicles following endocytosis, with no nuclear localization, but other studies have reported alterations in gene expression profiles in cells following exposure to gold nanorods, via unknown mechanisms. In this work we describe a pathway that can contribute to this phenomenon.

Oligodendroglia Are Particularly Vulnerable to Oxidative Damage after Neurotrauma .

Loss of function following injury to the CNS is worsened by secondary degeneration of neurons and glia surrounding the injury and is initiated by oxidative damage. However, it is not yet known which cellular populations and structures are most vulnerable to oxidative damage Using Nanoscale secondary ion mass spectrometry (NanoSIMS), oxidative damage was semiquantified within cellular subpopulations and structures of optic nerve vulnerable to secondary degeneration, following a partial transection of the optic nerve in adult female PVG rats. Simultaneous assessment of cellular subpopulations and structures revealed oligodendroglia as the most vulnerable to DNA oxidation following injury.

Corrigendum: Using Aiptasia as a Model to Study Metabolic Interactions in Cnidarian- Symbioses.

[This corrects the article on p. 214 in vol. 9, PMID: 29615919.

Using Aiptasia as a Model to Study Metabolic Interactions in Cnidarian- Symbioses.

The symbiosis between cnidarian hosts and microalgae of the genus provides the foundation of coral reefs in oligotrophic waters. Understanding the nutrient-exchange between these partners is key to identifying the fundamental mechanisms behind this symbiosis, yet has proven difficult given the endosymbiotic nature of this relationship. In this study, we investigated the respective contribution of host and symbiont to carbon and nitrogen assimilation in the coral model anemone Aiptaisa.

Three dimensional electron microscopy reveals changing axonal and myelin morphology along normal and partially injured optic nerves.

Following injury to the central nervous system, axons and myelin distinct from the initial injury site undergo changes associated with compromised function. Quantifying such changes is important to understanding the pathophysiology of neurotrauma; however, most studies to date used 2 dimensional (D) electron microscopy to analyse single sections, thereby failing to capture changes along individual axons. We used serial block face scanning electron microscopy (SBF SEM) to undertake 3D reconstruction of axons and myelin, analysing optic nerves from normal uninjured female rats and following partial optic nerve transection.

Dissecting the Re-Os molybdenite geochronometer.

Rhenium and osmium isotopes have been used for decades to date the formation of molybdenite (MoS), a common mineral in ore deposits and the world's main source of molybdenum and rhenium. Understanding the distribution of parent Re and radiogenic daughter Os isotopes in molybdenite is critical in interpreting isotopic measurements because it can compromise the accurate determination and interpretation of mineralization ages. In order to resolve the controls on the distribution of these elements, chemical and isotope mapping of MoS grains from representative porphyry copper-molybdenum deposits were performed using electron microprobe and nano-scale secondary ion mass spectrometry.

Managing the excessive proliferation of glycogen accumulating organisms in industrial activated sludge by nitrogen supplementation: A FISH-NanoSIMS approach.

Defluviicoccus vanus-related glycogen accumulating organisms (GAO) regularly proliferate in industrial wastewater treatment plants handling high carbon but nitrogen deficient wastes. When GAO dominate, they are associated with poor performance, characterised by slow settling biomass and turbid effluents. Although their ecophysiology has been studied thoroughly in domestic waste treatment plants, little attention has been paid to them in aerobic industrial systems.

Subcellular tracking reveals the location of dimethylsulfoniopropionate in microalgae and visualises its uptake by marine bacteria.

Phytoplankton-bacteria interactions drive the surface ocean sulfur cycle and local climatic processes through the production and exchange of a key compound: dimethylsulfoniopropionate (DMSP). Despite their large-scale implications, these interactions remain unquantified at the cellular-scale. Here we use secondary-ion mass spectrometry to provide the first visualization of DMSP at sub-cellular levels, tracking the fate of a stable sulfur isotope (S) from its incorporation by microalgae as inorganic sulfate to its biosynthesis and exudation as DMSP, and finally its uptake and degradation by bacteria.

High-resolution sub-cellular imaging by correlative NanoSIMS and electron microscopy of amiodarone internalisation by lung macrophages as evidence for drug-induced phospholipidosis.

Correlative NanoSIMS and EM imaging of amiodarone-treated macrophages shows the internalisation of the drug at a sub-cellular level and reveals its accumulation within the lysosomes, providing direct evidence for amiodarone-induced phospholipidosis. Chemical fixation using tannic acid effectively seals cellular membranes aiding intracellular retention of diffusible drugs.

Characterization of polymeric nanoparticles for treatment of partial injury to the central nervous system.

Before using nanoparticles for therapeutic applications, it is necessary to comprehensively investigate nanoparticle effects, both and . In the associated research article [1] we generate multimodal polymeric nanoparticles functionalized with an antibody, that are designed to deliver an anti-oxidant to astrocytes. Here we provide additional data demonstrating the effects of the nanoparticle preparations on an indicator of oxidative stress in an immortalized Müller cell line .

Imaging the uptake of nitrogen-fixing bacteria into larvae of the coral Acropora millepora.

Diazotrophic bacteria are instrumental in generating biologically usable forms of nitrogen by converting abundant dinitrogen gas (N2) into available forms, such as ammonium. Although nitrogen is crucial for coral growth, direct observation of associations between diazotrophs and corals has previously been elusive. We applied fluorescence in situ hybridization (FISH) and nanoscale secondary ion mass spectrometry to observe the uptake of (15)N-enriched diazotrophic Vibrio sp.

Light microenvironment and single-cell gradients of carbon fixation in tissues of symbiont-bearing corals.

Recent coral optics studies have revealed the presence of steep light gradients and optical microniches in tissues of symbiont-bearing corals. Yet, it is unknown whether such resource stratification allows for physiological differences of Symbiodinium within coral tissues. Using a combination of stable isotope labelling and nanoscale secondary ion mass spectrometry, we investigated in hospite carbon fixation of individual Symbiodinium as a function of the local O2 and light microenvironment within the coral host determined with microsensors.

Exploring the transfer of recent plant photosynthates to soil microbes: mycorrhizal pathway vs direct root exudation.

Plants rapidly release photoassimilated carbon (C) to the soil via direct root exudation and associated mycorrhizal fungi, with both pathways promoting plant nutrient availability. This study aimed to explore these pathways from the root's vascular bundle to soil microbial communities. Using nanoscale secondary ion mass spectrometry (NanoSIMS) imaging and (13) C-phospho- and neutral lipid fatty acids, we traced in-situ flows of recently photoassimilated C of (13) CO2 -exposed wheat (Triticum aestivum) through arbuscular mycorrhiza (AM) into root- and hyphae-associated soil microbial communities.

Viruses as new agents of organomineralization in the geological record.

Viruses are the most abundant biological entities throughout marine and terrestrial ecosystems, but little is known about virus-mineral interactions or the potential for virus preservation in the geological record. Here we use contextual metagenomic data and microscopic analyses to show that viruses occur in high diversity within a modern lacustrine microbial mat, and vastly outnumber prokaryotes and other components of the microbial mat. Experimental data reveal that mineral precipitation takes place directly on free viruses and, as a result of viral infections, on cell debris resulting from cell lysis.

Changes in subtypes of Ca microdomains following partial injury to the central nervous system.

Rapid changes in Ca(2+) concentration and location in response to injury play key roles in a range of biological systems. However, quantitative analysis of changes in size and distribution of Ca(2+) microdomains in specific cell types in whole tissue samples has been limited by analytical resolution and reliance on indirect Ca(2+) indicator systems. Here, we combine the unique advantages of nanoscale secondary ion mass spectrometry (NanoSIMS) with immunohistochemistry to directly quantify changes in number, size and intensity of Ca microdomains specific to axonal or glial regions vulnerable to spreading damage following neurotrauma.

Elemental and isotopic imaging of biological samples using NanoSIMS.

With its low detection limits and the ability to analyze most of the elements in the periodic table, secondary ion mass spectrometry (SIMS) represents one of the most versatile in situ analytical techniques available, and recent developments have resulted in significant advantages for the use of imaging mass spectrometry in biological and biomedical research. Increases in spatial resolution and sensitivity allow detailed interrogation of samples at relevant scales and chemical concentrations. Advances in dynamic SIMS, specifically with the advent of NanoSIMS, now allow the tracking of stable isotopes within biological systems at subcellular length scales, while static SIMS combines subcellular imaging with molecular identification.

High-resolution secondary ion mass spectrometry analysis of carbon dynamics in mycorrhizas formed by an obligately myco-heterotrophic orchid.

Mycorrhiza formation represents a significant carbon (C) acquisition alternative for orchid species, particularly those that remain achlorophyllous through all life stages. As it is known that orchid mycorrhizas facilitate nutrient transfer (most notably of C), it has not been resolved if C transfer occurs only after lysis of mycorrhizal structures (fungal pelotons) or also across the mycorrhizal interface of pre-lysed pelotons. We used high-resolution secondary ion mass spectrometry (nanoSIMS) and labelling with enriched (13) CO2 to trace C transfers, at subcellular scale, across mycorrhizal interfaces formed by Rhizanthella gardneri, an achlorphyllous orchid.

Competition between plant and bacterial cells at the microscale regulates the dynamics of nitrogen acquisition in wheat (Triticum aestivum).

The ability of plants to compete effectively for nitrogen (N) resources is critical to plant survival. However, controversy surrounds the importance of organic and inorganic sources of N in plant nutrition because of our poor ability to visualize and understand processes happening at the root-microbial-soil interface. Using high-resolution nano-scale secondary ion mass spectrometry stable isotope imaging (NanoSIMS-SII), we quantified the fate of ¹⁵N over both space and time within the rhizosphere.

NanoSIMS multi-element imaging reveals internalisation and nucleolar targeting for a highly-charged polynuclear platinum compound.

Simultaneous multi-element imaging using NanoSIMS (nano-scale secondary ion mass spectrometry), exploiting the novel combination of (195)Pt and (15)N in platinum-am(m)ine antitumour drugs, provides information on the internalisation and subcellular localisation of both metal and ligands, and allows identification of ligand exchange.

Nanoscale analysis of pyritized microfossils reveals differential heterotrophic consumption in the ~1.9-Ga Gunflint chert.

The 1.88-Ga Gunflint biota is one of the most famous Precambrian microfossil lagerstätten and provides a key record of the biosphere at a time of changing oceanic redox structure and chemistry. Here, we report on pyritized replicas of the iconic autotrophic Gunflintia-Huroniospora microfossil assemblage from the Schreiber Locality, Canada, that help capture a view through multiple trophic levels in a Paleoproterozoic ecosystem.

Visualising gold inside tumour cells following treatment with an antitumour gold(I) complex.

Gold(I) phosphine complexes, such as [Au(d2pype)(2)]Cl, (1, where d2pype is 1,2-bis(di-2-pyridyl phosphinoethane)), belong to a class of promising chemotherapeutic candidates that have been shown to be selectively toxic to tumourigenic cells, and may act via uptake into tumour cell mitochondria. For a more holistic understanding of their mechanism of action, a deeper knowledge of their subcellular distribution is required, but to date this has been limited by a lack of suitable imaging techniques. In this study the subcellular distribution of gold was visualised in situ in human breast cancer cells treated with 1, using nano-scale secondary ion mass spectrometry.