B24-Cryo Soft X-ray Tomography
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Ilias
Kounatidis
,
Megan L.
Stanifer
,
Michael A.
Phillips
,
Perrine
Paul-Gilloteaux
,
Xavier
Heiligenstein
,
Hongchang
Wang
,
Chidinma
Okolo
,
Thomas M.
Fish
,
Matthew C.
Spink
,
David I.
Stuart
,
Ilan
Davis
,
Steeveh
Boulant
,
Jonathan M.
Grimes
,
Ian M.
Dobbie
,
Maria
Harkiolaki
Diamond Proposal Number(s):
[21046, 18314]
Open Access
Abstract: Imaging of biological matter across resolution scales entails the challenge of preserving the direct and unambiguous correlation of subject features from the macroscopic to the microscopic level. Here, we present a correlative imaging platform developed specifically for imaging cells in 3D under cryogenic conditions by using X-rays and visible light. Rapid cryo-preservation of biological specimens is the current gold standard in sample preparation for ultrastructural analysis in X-ray imaging. However, cryogenic fluorescence localization methods are, in their majority, diffraction-limited and fail to deliver matching resolution. We addressed this technological gap by developing an integrated, user-friendly platform for 3D correlative imaging of cells in vitreous ice by using super-resolution structured illumination microscopy in conjunction with soft X-ray tomography. The power of this approach is demonstrated by studying the process of reovirus release from intracellular vesicles during the early stages of infection and identifying intracellular virus-induced structures.
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Jun 2020
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I08-Scanning X-ray Microscopy beamline (SXM)
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Diamond Proposal Number(s):
[17801, 17203]
Abstract: The good biocompatibility and corrosion resistance of the bulk CoCrMo alloy has resulted in it being used in the manufacture of implants and load bearing medical devices. These devices, however, can release wear and corrosion products which differ from the composition of the bulk CoCrMo alloy. The physicochemical characteristics of the particles and the associated in vivo reactivity are dictated by the wear mechanisms and electrochemical conditions at the sites of material loss. Debris released from CoCrMo hip bearings, taper junctions, or cement–stem interfaces can, therefore, have different chemical and morphological characteristics, which provide them with different in vivo toxicities. Here, we propose to assess and compare the characteristics of the particles released in vivo from CoCrMo tapers and cement–stem interfaces which have received less attention compared to debris originating from the hip bearings. The study uses state‐of‐art characterization techniques to provide a detailed understanding of the size, morphology, composition, and chemistry of the particles liberated from the wear and corrosion flakes from revised hip replacements, with an enzymatic treatment. The phase analyses identified Cr2O3 nanoparticles released from tapers and cement–stem interfaces, whose composition did not vary with origin or particle morphology. The size distributions showed significantly smaller particles were released from the stems, compared to the particles originating from the corresponding tapers. The investigation demonstrates that the tribocorrosive processes occurring at the taper and stem interfaces both result in Cr2O3 nanoparticle formation.
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Jun 2020
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B24-Cryo Soft X-ray Tomography
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Diamond Proposal Number(s):
[21046, 18314]
Abstract: Researchers have developed a new technique for studying cells in their native state. The goal was to obtain high-quality imaging data from cells without the need for sectioning or chemical fixation. The new method avoids any treatment that would disturb cell structure, so that no artefacts (errors) are introduced into the images.
To demonstrate this novel correlative microscopy platform’s effectiveness, the team studied the early stages of cell infection by reoviruses. Although the specific viruses have been studied extensively, there is a debate regarding the method of infection. This research focused on the way that the virus escapes from vesicles, a required step for replication. At beamline B24, using a correlative imaging approach by combining soft X-ray tomography with super resolution microscopy in cryogenic conditions, the team tracked the infection mechanism. The results revealed that the virus had already escaped from the host vesicles two hours after infection, with the vesicles preserving their circular shape, suggesting a gentle, pore-based exit mechanism for the virus.
Reoviruses are valuable tools that could be engineered to express proteins and have the potential to be used in vaccines. Knowing the infection mechanism will facilitate their handling and manipulation for biomedical purposes. The new imaging platform has also been used to validate anticancer compounds, study cell structure during development and investigate clearance of human pathogenic microorganism by immune host cells. The work is the outcome of a collective effort between Diamond Light Source and research groups and facilities across Europe, including the University of Oxford, Heidelberg University Hospital, the Université de Nantes and CryoCapCell.
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Jul 2021
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I08-Scanning X-ray Microscopy beamline (SXM)
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Diamond Proposal Number(s):
[20900]
Open Access
Abstract: We report on the detection of primordial organic matter within the carbonaceous chondrite Maribo that is distinct from the majority of organics found in extraterrestrial samples. We have applied high-spatial resolution techniques to obtain C-N isotopic compositions, chemical, and structural information of this material. The organic matter is depleted in 15N relative to the terrestrial value at around δ15N ~ -200‰, close to compositions in the local interstellar medium. Morphological investigations by electron microscopy revealed that the material consists of µm- to sub-µm-sized diffuse particles dispersed within the meteorite matrix. Electron energy loss and synchrotron X-ray absorption near-edge structure spectroscopies show that the carbon functional chemistry is dominated by aromatic and C=O bonding environments similar to primordial organics from other carbonaceous chondrites. The nitrogen functional chemistry is characterized by C-N double and triple bonding environments distinct from what is usually found in 15N-enriched organics from aqueously altered carbonaceous chondrites. Our investigations demonstrate that Maribo represents one of the least altered CM chondrite breccias found to date and contains primordial organic matter, probably originating in the interstellar medium.
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Nov 2020
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I08-Scanning X-ray Microscopy beamline (SXM)
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Diamond Proposal Number(s):
[20567]
Abstract: To assess the safety of engineered nanomaterials (ENMs) and to evaluate and improve ENMs’ targeting ability for medical application, it is necessary to analyze the fate of these materials in biological media. This protocol presents a workflow that allows researchers to determine, characterize and quantify metal-bearing ENMs (M-ENMs) in biological tissues and cells and quantify their dynamic behavior at trace-level concentrations. Sample preparation methods to enable analysis of M-ENMs in a single cell, a cell layer, tissue, organ and physiological media (e.g., blood, gut content, hemolymph) of different (micro)organisms, e.g., bacteria, animals and plants are presented. The samples are then evaluated using fit-for-purpose analytical techniques e.g., single-cell inductively coupled plasma mass spectrometry, single-particle inductively coupled plasma mass spectrometry and synchrotron X-ray absorption fine structure, providing a protocol that allows comprehensive characterization and quantification of M-ENMs in biological matrices. Unlike previous methods, the protocol uses no fluorescent dyes or radiolabels to trace M-ENMs in biota and enables analysis of most M-ENMs at cellular, tissue and organism levels. The protocols can be applied by a wide variety of users depending on the intended purpose of the application, e.g., to correlate toxicity with a specific particle form, or to understand the absorption, distribution and excretion of M-ENMs. The results facilitate an understanding of the biological fate of M-ENMs and their dynamic behavior in biota. Performing the protocol may take 7–30 d, depending on which combination of methods is applied.
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Jun 2022
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I08-Scanning X-ray Microscopy beamline (SXM)
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Diamond Proposal Number(s):
[15230]
Open Access
Abstract: Background: Neuromelanin-pigmented neurons, which are highly susceptible to neurodegeneration in the Parkinson’s disease substantia nigra, harbour elevated iron levels in the diseased state. Whilst it is widely believed that neuronal iron is stored in an inert, ferric form, perturbations to normal metal homeostasis could potentially generate more reactive forms of iron capable of stimulating toxicity and cell death. However, non-disruptive analysis of brain metals is inherently challenging, since use of stains or chemical fixatives, for example, can significantly influence metal ion distributions and/or concentrations in tissues. Aims: The aim of this study was to apply synchrotron soft x-ray spectromicroscopy to the characterisation of iron deposits and their local environment within neuromelanin-containing neurons of Parkinson’s disease substantia nigra. Methods: Soft x-ray spectromicroscopy was applied in the form of Scanning Transmission X-ray Microscopy (STXM) to analyse resin-embedded tissue, without requirement for chemically disruptive processing or staining. Measurements were performed at the oxygen and iron K-edges in order to characterise both organic and inorganic components of anatomical tissue using a single label-free method. Results: STXM revealed evidence for mixed oxidation states of neuronal iron deposits associated with neuromelanin clusters in Parkinson’s disease substantia nigra. The excellent sensitivity, specificity and spatial resolution of these STXM measurements showed that the iron oxidation state varies across sub-micron length scales. Conclusions: The label-free STXM approach is highly suited to characterising the distributions of both inorganic and organic components of anatomical tissue, and provides a proof-of-concept for investigating trace metal speciation within Parkinson’s disease neuromelanin-containing neurons.
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May 2020
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I08-Scanning X-ray Microscopy beamline (SXM)
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James
Everett
,
Frederik
Lermyte
,
Jake
Brooks
,
Vindy
Tjendana-Tjhin
,
Germán
Plascencia-Villa
,
Ian
Hands-Portman
,
Jane M.
Donnelly
,
Kharmen
Billimoria
,
George
Perry
,
Xiongwei
Zhu
,
Peter J.
Sadler
,
Peter B.
O'Connor
,
Joanna F.
Collingwood
,
Neil D.
Telling
Diamond Proposal Number(s):
[15854]
Open Access
Abstract: The chemistry of copper and iron plays a critical role in normal brain function. A variety of enzymes and proteins containing positively charged Cu+, Cu2+, Fe2+, and Fe3+ control key processes, catalyzing oxidative metabolism and neurotransmitter and neuropeptide production. Here, we report the discovery of elemental (zero–oxidation state) metallic Cu0 accompanying ferromagnetic elemental Fe0 in the human brain. These nanoscale biometal deposits were identified within amyloid plaque cores isolated from Alzheimer’s disease subjects, using synchrotron x-ray spectromicroscopy. The surfaces of nanodeposits of metallic copper and iron are highly reactive, with distinctly different chemical and magnetic properties from their predominant oxide counterparts. The discovery of metals in their elemental form in the brain raises new questions regarding their generation and their role in neurochemistry, neurobiology, and the etiology of neurodegenerative disease.
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Jun 2021
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I08-Scanning X-ray Microscopy beamline (SXM)
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Christina L.
Davis
,
Ryan A.
Venturelli
,
Alexander B.
Michaud
,
Jon R.
Hawkings
,
Amanda M.
Achberger
,
Trista J.
Vick-Majors
,
Brad E.
Rosenheim
,
John E.
Dore
,
August
Steigmeyer
,
Joel D.
Barker
,
Liane G.
Benning
,
Matthew R.
Siegfried
,
John C.
Priscu
,
Brent C.
Christner
,
Carlo
Barbante
,
Mark
Bowling
,
Justin
Burnett
,
Timothy
Campbell
,
Billy
Collins
,
Cindy
Dean
,
Dennis
Duling
,
Helen A.
Fricker
,
Alan
Gagnon
,
Christopher
Gardner
,
Dar
Gibson
,
Chloe
Gustafson
,
David
Harwood
,
Jonas
Kalin
,
Kathy
Kasic
,
Ok-Sun
Kim
,
Edwin
Krula
,
Amy
Leventer
,
Wei
Li
,
W. Berry
Lyons
,
Patrick
Mcgill
,
James
Mcmanis
,
David
Mcpike
,
Anatoly
Mironov
,
Molly
Patterson
,
Graham
Roberts
,
James
Rot
,
Cathy
Trainor
,
Martyn
Tranter
,
John
Winans
,
Bob
Zook
,
Mark L.
Skidmore
Diamond Proposal Number(s):
[25828]
Open Access
Abstract: Ice streams that flow into Ross Ice Shelf are underlain by water-saturated sediments, a dynamic hydrological system, and subglacial lakes that intermittently discharge water downstream across grounding zones of West Antarctic Ice Sheet (WAIS). A 2.06 m composite sediment profile was recently recovered from Mercer Subglacial Lake, a 15 m deep water cavity beneath a 1087 m thick portion of the Mercer Ice Stream. We examined microbial abundances, used 16S rRNA gene amplicon sequencing to assess community structures, and characterized extracellular polymeric substances (EPS) associated with distinct lithologic units in the sediments. Bacterial and archaeal communities in the surficial sediments are more abundant and diverse, with significantly different compositions from those found deeper in the sediment column. The most abundant taxa are related to chemolithoautotrophs capable of oxidizing reduced nitrogen, sulfur, and iron compounds with oxygen, nitrate, or iron. Concentrations of dissolved methane and total organic carbon together with water content in the sediments are the strongest predictors of taxon and community composition. δ¹³C values for EPS (−25 to −30‰) are consistent with the primary source of carbon for biosynthesis originating from legacy marine organic matter. Comparison of communities to those in lake sediments under an adjacent ice stream (Whillans Subglacial Lake) and near its grounding zone provide seminal evidence for a subglacial metacommunity that is biogeochemically and evolutionarily linked through ice sheet dynamics and the transport of microbes, water, and sediments beneath WAIS.
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Jan 2023
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B18-Core EXAFS
I08-Scanning X-ray Microscopy beamline (SXM)
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Diamond Proposal Number(s):
[20567, 20204]
Open Access
Abstract: Understanding the potential of nanomaterials (NMs) to cross the blood–brain barrier (BBB), as a function of their physicochemical properties and subsequent behavior, fate, and adverse effect beyond that point, is vital for evaluating the neurological effects arising from their unintentional entry into the brain, which is yet to be fully explored. This is not only due to the complex nature of the brain but also the existing analytical limitations for characterization and quantification of NMs in the complex brain environment. By using a fit-for-purpose analytical workflow and an in vitro BBB model, we show that the physiochemical properties of metallic NMs influence their biotransformation in biological matrices, which in turn modulates the transport form, efficiency, amounts, and pathways of NMs through the BBB and, consequently, their neurotoxicity. The data presented here will support in silico modeling and prediction of the neurotoxicity of NMs and facilitate the tailored design of safe NMs.
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Jul 2021
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I08-Scanning X-ray Microscopy beamline (SXM)
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Diamond Proposal Number(s):
[21323, 20839, 23049]
Open Access
Abstract: The coprecipitation of organic carbon with iron minerals is important for its preservation in soils and sediments, but the mechanisms for carbon-iron interactions and thus the controls on organic carbon cycling are far from understood. Here we coprecipitate carboxylic acids with iron (oxyhydr)oxide ferrihydrite and use near-edge X-ray absorption fine structure spectroscopy and wet chemical treatments to determine the relationship between sequestration mechanism and organic carbon stability against its release and chemical oxidative remineralisation. We show that organic carbon sequestration, stabilisation and persistence increase with an increasing number of carboxyl functional groups. We suggest that carboxyl-richness provides an important control on organic carbon preservation in the natural environment. Our work offers a mechanistic basis for understanding the stability and persistence of organic carbon in soils and sediments, which might be used to develop an overarching relationship between organic functional group-richness, mineral interactions and organic carbon preservation in the Earth system.
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Nov 2021
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